Monthly Archives: June 2023

It is worth noting that the current interface to the Island requires no typing beyond the initial login

There is a flat list of the 175 tasks currently available with few constraints on how they can be used. This gives students freedom in the experiments they design. Some of the tasks apply treatments, such as giving the subject a tablet containing 1 mg of alprazolam or making them swim freestyle for 200 m. These do not show any output in the interface but the tasks have changed the state of the Islander in the simulation. Since the simulation happens in real time the students need to wait to observe effects. Other tasks then produce data, such as measuring blood pressure or pulse rate, or taking a blood or urine sample to detect a particular substance. The onus is on the student to develop the protocol for applying the treatments and making the measurements. In addition to tasks that mostly behaved like measurements, the students could also design a survey for their Islanders to complete. Questions that students were interested in asking were added to the system, along with a range of standard survey questions that we typically ask the students themselves . The Islanders would take longer to complete longer surveys, discouraging students from just asking all the questions. Some Islanders were predisposed to lie on the surveys,vertical farm systems particular for questions related to age and weight. Students can always tell they are lying because the actual age of each Islander is displayed on the profile and there is a measurement task for weighing an Islander. There is also a chance that an Islander will decline to respond to a survey. This chance varies between the different cultural groups on the Island making a pattern in non-response bias for students to explore.

The instructor can see all tasks assigned by an individual student to each Islander they used as well as Islanders that have been visited by the student but who have not had any tasks assigned to them . These monitoring tools provide a useful level of accountability for individual student work and also give the instructor a broad insight into how the environment is being used by their class.Villages and individuals, tasks and results are all navigated through mouse clicks on a web browser. This has made the Island well suited to the many mobile devices that now have touchscreen interfaces. For example, although it was released after the Island was conceived, the iPad has been an ideal hardware interface to the Island. Mobile devices are also useful with the Island since the experimental simulations run in real time. For example, students can allocate their treatments to subjects during group work in a computer lab and are then able to check on the subjects, such as monitoring blood pressure or some hormone level, while riding on a bus. The Islanders have a pair of chromosomes that they inherit in the usual way from their parents. The 256 ‘genes’ on each these chromosomes are used to determine a variety of attributes, including the physical characteristics seen in Figures 1, measures of disease susceptibility, and other parameters required by the task simulations described in Section 3.2. We give students access to this genetic information through a task that generates the analog of a micro-array image for one or both of the chromosomes. Students can use this task to carry out studies that mirror micro-array techniques in the real world. For example, Bulmer and Meiring describe a student project that looked for evidence of a gene linked to diabetes on the Island. In that study the student obtained micro-array images for 10 Islanders with diabetes and 10 without, giving the results shown in Figure 3.

The question is whether there is any systematic difference between the intensity levels expressed in each set of images. Figure 4 shows a more quantitative summary of the results with side-by-side box plots for each of the 256 genes appearing in the micro-arrays. For convenience we label the positions with B000 at top left, along to B015 at top right and then continuing by rows to B255 at bottom right. The student carried out a two-sample t test to compare the levels between the subjects with diabetes and those without for each of these. The four strongest effects were for genes B116 , B041 , B186 and B118 . Figure 5 shows the box plots for these four comparisons in more detail. For B116 the intensity distribution for non-diabetics seems uniform while it appears systematically lower for diabetics. We now use this student study as an example in class. Of course the p-value for B116 needs to be treated by caution since it arose from a large number of multiple comparisons. In our introductory course we use the very conservative Bonferroni adjustment to the p-values, whereby B116 becomes non-significant, but the overall example illustrates to students the practical issues involved in this kind of screening as well as an area of current research in the discipline of statistics itself. A great advantage of this approach is that new students can replicate the study if they want, or search for other similar genes.Our final example illustrates the open-endedness of the Island through a new measurement devised by a student based on the existing data. The student was interested in possible risk factors for smoking and she wanted to test the hypothesis that major life-changing events could increase the incidence of smoking due to stress. Using a sample of 40 Islanders, she counted the number of life-changing events each of them had experienced. She defined these to be any of illnesses, marriages, child births, loss of spouses and migration between villages. She recorded their current smoking status and then looked for a relationship between the two variables. A logistic model for the relationship is shown in Figure 6. This was an interesting outcome for the student since the conclusion was the opposite of her original hypothesis: there was significant evidence that Islanders with higher numbers of life-changing events were actually less likely to be smokers. However it was also a very interesting outcome for the authors because this relationship was not an explicit part of any of the simulation models.

This emergent phenomenon is most likely an example of survival bias in the results since smokers tend to die younger and so ultimately have less time to experience life-changing events. Future students can replicate this study and try to adjust for age, for example, to confirm whether this is the case. Student feedback to the Island has been very positive. In our context the role of it has been to replace real experiments and this is reflected in many comments such as that “they were interesting and a great way to find results of experiments. It made the experimentation process nice and easy to conduct”. However students were also engaged with the Islanders beyond a basic tool for generating data: “I liked how we were able to see their whole history on their profiles; it was interesting seeing some of their troubled past”. As mentioned earlier, we do have a tension between reality and fantasy in our design and it was interesting to read comments on the reality aspect, such as that “the Islanders were a little too real,vertical farming cost especially as they improved reaction times after repeating the action. We really had to think of them as real people – which I suppose was the whole point”. In contrast there have not been open comments on the ‘unreal’ aspects, such as the Islanders with elven ears or the unusual disease names. We suspect that students are used to these features in computer games and are not surprised by them. This is an interesting area for future studies. The consistent negative feedback has been on the Islanders sleeping each night. While some students were interested in studying sleep, as in the dextroamphetamine example above, for the majority of students the fact that the Islanders go into an uninterruptible sleep each night is often a nuisance. At this stage we are continuing to include this constraint, as part of our general philosophy summarized in the following section. However we have made the Islanders go to bed a bit later each night and have introduced some tasks that can be performed on sleeping Islanders, such as the various blood tests and a simple polysomnography tool, so that students are not completely stuck if they have left their project until the night before it is due. In general it is not surprising that the Island has been successful in engaging students with the task for which it was designed. We are interested now in evaluations from other users of the Island in contexts different from our own. For example, Linden et al.give outcomes of a research grant that has investigated the use of the Island as a tool in teaching clinical trial design and management. Edwards and Crowther give an evaluation of the Island in a health systems management course where the focus was not on statistical reasoning at all. Such projects give insight into the transferability of the tool while also feeding back ideas to further expand the models included in the simulated environment. Bulmer gives more details regarding this collaborative approach. Various preparations of the leaves, flowers and resinous extracts of the Cannabis plant have been consumed for both medical and recreational purposes since antiquity. Extensive research efforts aiming to explain the widespread therapeutic and behavioral effects evoked by Cannabis consumption finally led to the discovery of a new messenger system called the endocannabinoid system. It is composed of the CB1 and CB2 cannabinoid receptors , which are not only targets of the psychoactive compounds of the Cannabis plant, but more importantly, they are also activated by two endogenous lipid molecules produced by most cell types in the body . The mobilization and elimination of these two endocannabinoid molecules called N arachidonoylethanolamine and 2-arachidonoylglycerol are tightly regulated by surprisingly complex networks of metabolic enzymes and pathways in different cell types and tissues .

Following the clinical failure of brain-penetrating CB1 receptor antagonists as therapeutics due to adverse psychiatric effects, the identification of novel molecular players regulating endocannabinoid levels has opened new possibilities, because drugs targeting these enzymes may have more selective actions . The wide spectrum of human neurological and psychiatric diseases in which the endocannabinoid system is implicated suggests a vast therapeutic potential . However, to take advantage of this potential requires full characterization of the enzymes regulating endocannabinoid signaling in the human brain. A conceptual framework describing the major aspects of neuronal endocannabinoid signaling has emerged from the results of numerous animal studies in the last decade. In contrast to conventional neurotransmitters, endocannabinoids are primarily synthesized and released by postsynaptic neurons in an on-demand manner , and subsequently activate presynaptically located CB1 cannabinoid receptors, thereby regulating neurotransmitter release from several types of axon terminals . This retrograde manner of synaptic endocannabinoid signaling is indispensable for various forms of homo- and heterosynaptic plasticity throughout the central nervous system , and probably accounts for the extensive involvement of the endocannabinoid system in brain disorders . Thus, molecular mechanisms regulating synaptic endocannabinoid signaling may be of pivotal importance in the therapeutic exploitation of the endocannabinoid system. Although anandamide is the archetypical endocannabinoid molecule , and may tonically control presynaptic CB1 receptors , most experimental evidence converge on the notion that 2-AG is the crucial retrograde messenger mediating on-demand forms of short- and long-term synaptic depression through CB1 activation. Pharmacological inhibition of diacylglycerol lipase, including its alpha isoform, the enzyme primarily responsible for 2-AG biosynthesis in adult brain , prevents retrograde endocannabinoid signaling in various experimental paradigms throughout the cerebral cortex . Particularly compelling support for this concept also derives from the genetic inactivation of DGL-α, which completely abolishes endocannabinoid-mediated synaptic plasticity, for example in the hippocampus . Conversely, pharmacological blockade of monoacylglycerol lipase , the enzyme responsible for inactivation of the major fraction of 2-AG in the brain , prolongs retrograde endocannabinoid signaling in distinct types of synapses . Widespread distribution of 2-AG in the human brain has recently been revealed with a largely overlapping regional pattern to CB1 receptors based on radioligand binding and in situ hybridization experiments .

The first is the activity-dependent cleavage of the phospholipid precursor N-arachido noyl-PE

All participants receive an honorarium of $C40 at each biannual visit for their time, expertise and travel. To capture initial episodes of suicidality, analyses for this study were restricted to AESHA participants who had never thought about or attempted suicide at base line and completed at least one follow-up visit between January 2010 and August 2014. Those with missing observations for suicidality at baseline were excluded from analysis, and one additional participant was excluded because reported suicidality was missing at follow-up.This study demonstrated that among marginalised women, many of whom are street-involved and experience a disproportionate burden of violence, trauma, psycho logical distress and suicide, naturalistic psychedelic drug use predicted a significantly reduced hazard for suicidality. Crystal methamphetamine use and childhood abuse predisposed women to suicidality corresponding to more than a threefold increased hazard. Suicidality was highly prevalent, with almost half of women reporting lifetime suicidality at baseline, and 11% reporting a first episode of suicidality in the last 6months during follow-up. Few studies have longitudinally examined predictors of suicidality among marginalised sex workers, and of the avail able data, most are cross-sectional and/or conducted in lower-income and middle-income settings.The present study, based on a community-based, prospective cohort of marginalised women, adds to a growing body of literature documenting the protective and therapeutic potentials of psychedelic substances.Data were self-reported, and questions pertaining to events that occurred in the past may be subject to recallbias. Variables examined included sensitive and highly stigmatised topics such as childhood trauma, violence and illicit drug use,greenhouse vertical farming which introduce the potential for social desirability and reporting bias.

However, the likelihood of these biases is reduced by the community-based nature of the study. While lifetime psychedelic drug use was found to reduce the hazard of suicidality, the associations uncovered in this analysis cannot be determined as causal. However, the use of Cox regression analysis in this study was able to determine a temporal relationship between psychedelic use and suicidality. The sample was restricted to participants who had not experienced suicidal ideation or attempt at baseline, ensuring that psychedelic use preceded suicidality and thus providing evidence that psychedelics have a protective effect. Due to a lack of statistical power, analyses evaluating the effects of more nuanced indicators of psychedelic use , as well as separate analyses for ideation and attempt outcomes, were not feasible. Further exam ination of these variables would certainly be interesting and important in future analyses with additional data from follow-up questionnaires. Suicidality is influenced by complex individual, interpersonal and structural variables, and not all potential confounding variables could be controlled for in this study. For example, women who use psychedelics may also possess some characteristic associated with a reduced likelihood of being suicidal , which were not examined in this study. Despite the relative safety of psychedelic drug use as evidenced from the clinical and non-clinical literature,it should be noted that the use of psychedelics, particularly with unknown doses sourced from unregulated street markets, is not without risk, highlighting the importance of set and setting; the doses and contexts of psychedelic use among women in the present study could not be determined. The SE for the association between psychedelic use and suicidality was somewhat high, resulting in a wider CI. However, a large and significant protective effect was demonstrated in multivariable analysis, despite the relatively small number of events for suicidality over follow-up. With a larger sample size, we would expect a narrower CI for this association. The study population included women from a wide-ranging representation of sex work environments, yet findings may not be fully generalisable to sex workers in other settings.

The mapping of working areas and time–location sampling helped to ensure a representative sample and to minimise selection bias. To the best of our knowledge, this study is the first to longitudinally investigate associations with suicidality among marginalised and street-involved sex workers in North America and builds on prior cross-sectional research highlighting significantly elevated rates of suicidality and unmet mental health needs in this population. For example, a study conducted in Sydney, Australia demon strated significant links between depression, trauma, and suicidality, where an estimated 42% of street-based female sex workers reported attempting suicide and 74% reported lifetime suicidal ideation.While estimates of mental illness vary significantly across sex work settings, up to three-quarters of street-involved and drug-involved sex workers in a US study reported severe depression, anxiety or PTSD.Notably, our study demonstrated a lower risk of suicidality among women working indoors in bivariate analysis , lending support to the critical role of safer workplace environments in mitigating risk. In studies conducted in Asia, recent suicide attempts ranged from 19% among sex workers in Goa, India to 38% among sex workers in China,many of whom work in marginalised settings with few workplace protections. Transgender women involved in sex work, a sub-population experiencing significant psychosocial vulnerability and discrimination, report notably further elevated rates of suicidality: three-quarters of participants in San Francisco reported suicide ideation, of whom 64% attempted suicide.The global evidence is unequivocal that in settings where sex work is criminalised, sex workers are unable to access essential social, health and legal protections , highlighting the need for structural and community-led interventions to improve health and human rights.A structural approach to mitigating suicidality risk requires a reform of laws and policies that perpetuate stigma, discrimination, violence and unequal access to health and social supports among sex workers. Increased support for community-driven interventions that are gender and culturally appropriate are urgently needed, and any clinical treatment utilising psychedelics must be developed alongside sex worker-led interventions and community empowerment.

Our findings extend on research on associations between lifetime use of illicit drugs and increased risk for suicidality: in bivariate analysis, all classes of illicit drugs were demonstrated to increase the hazard of suicidality with the exception of psychedelics. In multivariable analysis, psychedelics were independently associated with a 60% reduced hazard for suicidality, contributing to emergent evidence on the potential of psychedelics to mitigate risks for suicide. Among the various scientific studies examining the potential benefits of psychedelic drug use, a recent and large population study conducted among adult respondents in the USA demonstrated that psyche delics are associated with reduced psychological distress and suicidality.A recent open-label trial conducted in the UK demonstrated the safety and efficacy of psilocybin for treating major depression, and another open-label trial in Brazil found rapid and sustained antidepressant effects from the Amazonian psychedelic brew ayahuasca administered in a clinical setting.The ways in which psychedelics may alleviate suffering associated with some mental illness is undoubtedly a complex phenomenon. It has been hypothesised that psychedelics modify neurobiological processes that may be involved in suicidality by down regulating 5-HT2A serotonin receptors,vertical farming investment as increased binding of this receptor has been implicated in major depression and suicide.Further more, there is evidence that psychedelics alter neural network connectivity and enhance recall of autobiograph ical memories, which may facilitate positive reprocessing of trauma.Recent randomised, placebo-controlled, crossover studies found that psilocybin and LSD were associated with increased positive mood and psychological well-being,supporting other work demonstrating the anti-depressive/ anxiolytic effects of psychedelics.The potential of psychedelics to elicit ‘mystical-type’ experiences, with profound and sustained positive changes in attitudes and mood, may play a key role in addiction treatment interventions.For example, psilocybin-assisted psychotherapy demonstrated high success in smoking cessation outcomes at 6months follow-up , and mystical experiences generated from the psilocybin sessions were significantly correlated with elevated ratings of personal meaningfulness, well-being and life satisfaction.Randomised control trials in the USA and Switzerland have demonstrated significant long term improvements among patients with treatment-resis tant PTSD following MDMA-assisted psychotherapy, and further research is continuing in an international multisite phase t3 clinical trial. Marginalised and street-based sex workers experience complex and synergistic effects between trauma, lack of workplace safety and mental health/substance use comorbidities that elevate risk of suicidality.

Marginal ised women and sex workers who use drugs report high rates of childhood abuse,which is associated with an increased likelihood of experiencing subsequent physical or sexual violence, as well as initiating injection drug use.For those suffering from emotional trauma stemming from violence, including indirect violence , there may be a proclivity to use drugs for self-medication. Violence and sexual coercion have been found to be significantly associated with suicidality among sex worker populations in China and India.As demonstrated in this study, having an early traumatic life event is a key risk factor for suicide among sex workers, a high proportion of whom are Indigenous, and experiencing historical trauma can have harmful intergenerational impacts.Given that historical experiences of violence and trauma denote significant risk for suicide, there is an urgent need to provide integrated, trauma-informed intervention services for sex workers and other marginalised populations. Currently available interventions and pharmaco logical treatments for suicidality show limited efficacy, and concerted efforts should be made to increase access to evidence-based treatments and to explore alternative approaches to improving mental health and well-being. Emerging research and evidence show positive outcomes with psychedelic-assisted treatments, which have demonstrated an excellent record of safety with few to no serious adverse effects reported.This study suggests psychedelic substances may hold promise as useful tools in addressing mental health issues and remediating risks for psychological distress and suicide.The increasing spread of marijuana use, especially among adolescents and young adults , has heightened societal awareness of the risks associated with this drug and has highlighted the need to fully understand its mechanism of action. Basic research has shown that D9 -tetrahydrocannabinol , the main active constituent of marijuana, produces its effects by combining with selective receptors present on the membrane of cells in the brain, the vasculature and the immune system . Research has also revealed that a group of lipid-derived substances produced by the body engages these receptors and participates in bio logical processes as diverse as painperception, memory formation and blood pressure regulation. This knowledge has allowed researchers to interpret the pharmacological properties of marijuana, but remains inadequate to the task of developing strategies for the medicinal management of marijuana dependence. No such strategies exist at present , despite the fact that pharmacotherapy—alone or in combination with behavioral therapy—is considered a primary treatment option for drug dependence when abuse prevention fails . Several basic questions, which are relevant to the pharmacotherapy of marijuana dependence, remain unanswered. For example, while it is clear that D9 -THC acts by hijacking the brain endocannabinoid system, its impact on the various components of this system—synthetic and catabolic enzymes, transporters, and receptors—is still largely undefined. Does D9 -THC produce rapid adaptive changes in neuronal endocannabinoid signaling, as recent evidence indicates ? And, if so, do such changes contribute to the pharmacological actions of the drug? Does prolonged exposure to D9 -THC cause stable alterations in endocannabinoid signaling? And, if so, do such alterations contribute to marijuana dependence and, most importantly, can they be safely reversed to restore normality? Answering these questions may not only help develop effective therapeutic strategies for marijuana dependence, but in light of the broad roles played by the endocannabinoid system in the control of brain reward processes , might also shed new light on fundamental mechanisms of drug addiction. To accomplish this task, it seems important to move forward in two convergent directions: the molecular characterization of endocannabinoid signaling, much of which is still uncharted; and the development of pharmacological agents that interfere with specific components of this system. In the present review, I outline recent progress made in these directions, specifically focusing on endocannabinoid deactivation, and discuss some of the challenges lying ahead.Anandamide was the first endocannabinoid sub stance to be isolated and structurally characterized . Its formationinneural cells is thought to require two enzymatic steps, which are illu strated in Fig. 1.This reaction, which is mediated by a unique D-type phospholipase , produces anandamide and phosphatidic acid, which is recycled to produce other glycerol-containing phospholipids. The cellular stores of NAPE are small, but canbe refilled by an N-acyltransferase activity, which catalyzes the intermolecular passage of anarachidonic acid group from the sn-1 positionof phosphatidylcholine to the head group of phos phatidylethanolamine . Incultures of rat cortical neurons, NAT activity is controlled by two intracellular second messengers: Ca2+, which is required to activate the enzyme, and cyclic 30 , 50 -adeno sine monophosphate , which stimulates protein kinase A-dependent protein phosphorylation and, via an unknown mechanism, enhances NAT activity .

Generalized cerebral grey matter atrophy has been shown to correlate with worse disease

We found that increased peak VL correlated with reduced total grey matter, bilateral rostral middle and superior frontal volumes. Youth with recent unsuppressed VL had smaller volumes for these regions, although associations attenuated after adjustment for sex, age at neuroimaging, and age at peak VL. Moreover, PHIV youth who reported alcohol and marijuana use showed further reduction in grey matter volumes compared with PHIV youth who reported no use. Finally, smaller volumes of primary ROIs and total grey matter correlated with lower performance on standardized measures of working memory, processing speed, and cognitive proficiency. Patterns of smaller volumes appeared to be symmetric bilaterally for these tested associations: 1) PHIV youth vs. typically-developing, HIV-unexposed and uninfected youth 2) higher peak VL and 3) recent unsuppressed VL for regions that were significantly different or trended towards significance. In addition to these selective losses associated with PHIV, higher VL, substance use,vertical harvest farms and poorer cognitive performance were also associated with smaller total grey matter volumes. Total decreased grey matter volume may be due to abnormal development in primary ROIs as well as subtler abnormalities in the rest of the brain that did not reach statistical significance after multiple comparisons with our sample size. Prior neuroimaging studies in adults with HIV have reported that HIV severity was related to reduced global and regional brain volumes in both untreated patients and those treated with cART . Findings on cortical changes varied but overlapped between studies.Some studies have identified frontal and parietal lobe grey matter volume loss ; others have shown volume loss in temporal and limbic regions . Cortical thinning has been reported in postcentral and precentral gyri with degree of atrophy correlating with cognitive impairment in HIV+ adults .

Our study of PHIV youth identifies reduced volume in the prefrontal cortex, a brain region not specifically reported in studies of adults with horizontally-transmitted HIV. Importantly, prefrontal regions undergo tremendous development during adolescence . Differences in findings between our study and prior studies could be due in part to differing patient populations and different environmental exposures . Although brain volumes in adults with horizontally-transmitted HIV have been studied, the long-term effects of HIV infection treated with cART on developing brains of adolescents have not been extensively examined . Importantly, PHIV youth are exposed to HIV and cART during critical developmental periods of the brain. Other studies of our PHIV cohort have found overall and regional white matter micro-structure and functional connectivity as well as subcortical deformation differences in those with worse HIV disease severity and/or compared to controls . In a recent study on another cohort of PHIV youth, Sarma et al. found that compared to age-matched controls, adolescents with PHIV had reduced white matter volume, but increased grey matter volumes in superior frontal and temporal gyri. Differences in findings between our studies may be due to the smaller sample size, more severe HIV disease and later onset of cART in the PHIV youth in the Sarma et al study . The authors suggest that larger grey matter volume may be due to inflammation. Another recent study on a slightly younger cohort of PHIV youth by Cohen et al. found that youth had lower overall grey matter volumes, but did not study regional differences compared to controls. We also found lower total grey matter volume in our cohort of PHIV, a geographically-different and older clinical population than in the Cohen et al. study. Importantly, our study also considered additional effects of substance use on brain structure as well as an examination of relationships between regional brain differences and cognition. Substance use in adolescence may lead to aberrant development during a vulnerable period of significant brain maturation and/or or pre-existing structural brain differences may lead to increased substance use .

Previous studies have demonstrated that adolescents who are more likely to drink alcohol have thinner frontal cortices and distributed regions in the frontal, parietal, temporal, and occipital lobes . A larger study of PHIV youth in the PHACS AMP study found that substance use among PHIV youth may lead to greater risky behavior . In our neuroimaging cohort, we found that substance use among PHIV youth may exacerbate total and regional grey matter reductions. Notably, PHIV youth who reported substance use had reductions in bilateral frontal gyri, regions involved in executive functioning, logical thinking, goal setting, planning, and self-control, which may be associated with decision-making and risky behaviors . While these findings are consistent with some studies on brain volume reductions among HIV-uninfected adolescents who use alcohol or marijuana, they also differ from others identifying increased volumes with marijuana use . Differing patterns found in our study may be due to dose-related effects; we examined ever-use, not frequency or duration of use. Moreover, concurrent marijuana and alcohol could have complex and perhaps interacting effects on brain structure . An additional consideration for interpreting our findings is that socioeconomic status may affect brain development. Previous studies have demonstrated that altered grey matter measures such as volume, cortical thickness, and surface area in distributed cortical and subcortical regions are associated with socioeconomic status . Despite differences in socioeconomic status between our HIV-unexposed and uninfected youth and PHIV youth cohorts, regional and total grey matter volume differences persisted after controlling for socioeconomic status. Unlike some previous studies, socioeconomic status alone was not associated with regional brain volume differences. There are some potential limitations to consider when interpreting our results. One limitation is the difficulty of teasing apart individual effects of PHIV, cART, and substance use on brain volumes. Although we attempted to address this limitation by including a measure of persistence of unsuppressed VL, we observed no associations with this measure; other cumulative measures of HIV severity may add additional insight on HIV effects on the brain.

Another limitation is the availability of only a single neuroimaging study during adolescence, making it more difficult to isolate effects of HIV, treatment, and preexisting pathology. A further limitation is that we only report cognitive and substance use findings in the PHIV youth and did not have comparable measures for the typically-developing control cohort. However, it should be noted that the relationship between brain volume changes in the general population is relatively well-researched and our volume findings in many regions in PHIV youth overlap with previous findings on cognition and substance use-brain volume findings in typically-developing youth . Finally, while our study only evaluated brain volumes with respect to HIV infection status and past HIV disease severity measures such as peak HIV RNA load and nadir CD4%, examining measures of inflammation and interleukins with respect to brain volumes may deepen our understanding of structural brain changes in youth with PHIV. Other studies have found that cognitive performance is related to a variety of cytokines and that certain cytokine markers, especially IL-6 and IL-16, significantly relate to brain volumes in adult HIV patients. Proton magnetic resonance spectroscopy studies have found that in adult HIV patients, elevated neurofilament light chain in the cerebrospinal fluid correlated with MRS abnormalities in the anterior cingulate, frontal white matter,vertical farming systems and parietal grey matter . In youth with PHIV, the relationship of brain volumes to inflammatory markers has not yet been studied, though studies in youth with PHIV have found that neopterin and sCD14 levels are elevated and that aggregate measures of fibrinogen, CRP, and IL-6 are associated with decreased processing speed in youth with PHIV and in uninfected youth with perinatal HIV exposure . Future studies should aim to assess effects of PHIV, cART, and substance use with longitudinal neuroimaging and include diverse measures of HIV disease severity and inflammation, which may provide more information on when the brain is most vulnerable to HIV and substance use, as well as when treatment is most effective. With increased longevity due to cART, preservation of neurological function becomes important for quality of life and adequate functional outcomes. Our study provides preliminary insight into the effects of HIV and substance use on the brain in PHIV youth as well as potential clinical biomarkers for evaluating HIV-related brain atrophy and cART efficacy in the brain. PHIV youth may demonstrate distinct and particular vulnerability toHIV compared to adults due to exposure to HIV and antiretroviral treatment during critical developmental periods. Older persons living with HIV , often defined as age 50 years, represent a rapidly growing population. More than 50% of PLWH in the U.S. are 50 years, . Furthermore, older PWLH have high rates of multi-morbidity . Chronic pain and substance use occur commonly in this population and are associated with poor health outcomes and increased use of healthcare services . PLWH are also at risk for declining physical functioning and reduced physical performance . Given the high prevalence of co-morbid pain, substance use, and reduced physical functioning in older PLWH, multi-component interventions targeting all three are needed. Cognitive behavioral therapy is an evidence-based approach for managing both pain and substance use .

According to the Infectious Diseases Society of America guidelines, CBT is a recommended first line non-pharmacologic treatment for chronic pain management among PLWH . In addition, exercise therapies reduce pain, reverse muscle atrophy, and decrease fall risk among older adults with chronic pain . Tai chi is a mind-body exercise that combines gentle movement, meditation and deep breathing. Tai chi can be feasibly administered to diverse groups of older adults and is associated with reduced pain, risk of falling and depressive symptomatology . Given high rates of physical deconditioning in PLWH , tai chi constitutes a particularly appealing movement-based therapy due to its use of low impact, graded, weight bearing exercises. Finally, text messaging has recently demonstrated efficacy in reinforcing elements of behavioral interventions, including those directed at changing addictive behaviors and managing chronic pain . Text messaging may also be an acceptable continuing care strategy following intensive treatment for a substance use disorder and in reducing problem drinking . We conducted a pilot randomized controlled trial to assess the feasibility, acceptability and preliminary efficacy of a multi-component behavioral intervention—a combined CBT and tai chi protocol reinforced with text messaging—to reduce levels of pain and substance use, and improve physical performance among older PLWH. We hypothesized that participants randomized to the intervention arm would demonstrate reductions in substance use, pain-related disability and pain intensity along with improvements in physical performance. Prior to the RCT, we conducted focus groups with prospective end users of the intervention to ascertain their preferences regarding behavioral treatments for pain ; developed the integrated intervention and trained APAIT staff to deliver it; and conducted a small pilot study, using the results to refine study materials and procedures prior to the current trial. We also obtained supplemental funding to conduct daily diary assessments of overall health, pain, behavioral responses to pain, mood, sleep, exercise, drinking and drug use, and social contact among all study participants via their cell phones. These data are reported in a separate paper . The Institutional Review Boards of all participating institutions approved the study. All participants provided written informed consent and participants assigned to the CBT/TC/TXT arm granted permission for the CBT sessions to be audiotaped.Study investigators developed an eight session, manualized treatment protocol to be delivered once weekly over 60 minutes in a group format by behavioral health counselors. The eight week, open-group program was adapted from three manualized interventions: 1) Manage Your Pain ; 2) Integrated CBT ; and 3) Mindfulness Based Relapse Prevention . All CBT sessions began with homework review, followed by delivery of didactic materials, coping skills, rehearsal exercises, and a new homework assignment. Therapy content focused on a different theme each week including 1) coping with chronic pain, 2) using mindfulness to cope with pain, 3) understanding and changing problematic patterns of substance use, 4) building motivation for change, 5) stress management and problem solving, 6) coping with negative thoughts and emotions, 7) improving sleep, and 8) building social support. Participants were given a copy of the client manual to facilitate between-session homework practice of coping skills presented in the weekly sessions. Three behavioral health counselors, including two members of APAIT’s staff, participated in a day-long training led by a Master’s level clinician experienced in administering manualized CBT interventions. To maintain fidelity during the trial, a clinical psychologist provided monthly supervision with review of audiotaped CBT sessions and feedback to counselors. Ongoing fidelity monitoring was conducted on all CBT sessions using a previously developed fidelity rating scale that assessed the extent of study therapists’ use of CBT-specific skills .

How To Start A Vertical Farm Business

Starting a vertical farm business involves several key steps. Here is a general guide to help you get started:

  1. Research and Planning:
    • Study vertical farming concepts, techniques, and technologies.
    • Identify suitable crops for vertical farming based on market demand, local conditions, and profitability.
    • Conduct market research to understand the potential customer base, competition, and market trends.
    • Develop a comprehensive business plan that includes your vision, goals, target market, financial projections, and marketing strategies.
  2. Acquire Necessary Knowledge and Skills:
    • Gain knowledge and skills in vertical farming techniques, hydroponics or aeroponics systems, plant nutrition, crop management, and pest control.
    • Consider attending workshops, courses, or obtaining relevant certifications to enhance your understanding and expertise in vertical farming.
  3. Secure Financing:
    • Estimate the startup costs based on your business plan, including infrastructure, equipment, technology, and operational expenses.
    • Seek funding options such as personal savings, loans, grants, or investment from partners or stakeholders.
    • Prepare a detailed financial projection, including revenue streams, expenses, and return on investment (ROI), to attract potential investors or lenders.
  4. Choose a Suitable Location:
    • Identify a suitable location for your vertical farm considering factors such as space availability, access to utilities, proximity to markets, and zoning regulations.
    • Consider factors like sufficient floor space, ceiling height, and access to natural light (or plan for artificial lighting).
  5. Set Up Infrastructure and Equipment:
    • Construct or retrofit the facility to meet the specific requirements of a vertical farm, including climate control, lighting systems, irrigation systems, and vertical growing structures.
    • Install necessary technology and equipment, such as LED grow lights, environmental control systems, nutrient delivery systems, and automation tools.
  6. Source Quality Plant Materials:
    • Identify reliable sources for obtaining high-quality seeds, seedlings, or tissue culture plants for your chosen crops.
    • Ensure proper handling and propagation techniques to maintain plant health and vigor.
  7. Establish Operational Procedures:
    • Develop standard operating procedures (SOPs) for seeding, transplanting, irrigation, nutrient management, pest and disease control, and harvesting.
    • Train your staff on proper farming practices, safety protocols, and maintaining optimal growing conditions.
  8. Market and Sell Your Produce:
    • Develop a marketing strategy to reach your target customers, whether it’s local consumers, restaurants, grocery stores, or wholesalers.
    • Build relationships with potential buyers, participate in farmers’ markets, and explore online sales platforms.
    • Emphasize the benefits of your vertical farm, such as fresh, locally grown produce, year-round availability, and sustainable farming practices.
  9. Monitor and Optimize:
    • Continuously monitor and optimize your operations, including crop performance, resource usage, and financial metrics.
    • Stay updated with the latest research and developments in vertical farming and implement improvements accordingly.

Starting a vertical farm requires careful planning, dedication, and ongoing learning. Collaborating with experts in the field, joining industry associations, and networking with other vertical farmers can also provide valuable insights and support.

Which Plants Can Be Grown In Vertical Farming

Vertical farming offers versatility in crop selection, allowing a wide range of plants to be grown in indoor, vertical environments. While some crops are particularly well-suited for vertical farming, the potential plant options are extensive. Here are some commonly grown plants in vertical farming systems:

  1. Leafy Greens: Lettuces (such as butterhead, romaine, and leaf lettuce), kale, spinach, Swiss chard, arugula, and microgreens are popular choices for vertical farming due to their fast growth, high demand, and compact size.
  2. Herbs: Basil, cilantro, parsley, mint, thyme, oregano, and other culinary herbs thrive in vertical farming systems. These herbs are often grown for their flavor, fragrance, and culinary applications.
  3. Strawberries: Vertical farming allows strawberries to be grown efficiently, making use of vertical space and maximizing yields. The controlled environment helps maintain consistent temperature and humidity, which is beneficial for strawberry cultivation.
  4. Tomatoes: Compact or determinate tomato varieties, such as cherry tomatoes or vine tomatoes, can be grown in vertical farming systems. Trellising or supporting the plants allows them to grow vertically and efficiently utilize the available space.
  5. Peppers: Bell peppers, chili peppers, and other varieties of peppers can be grown vertically, with the plants supported and trained to grow upward. Vertical farming provides a controlled environment for pepper production, allowing for consistent quality and yields.
  6. Cucumbers: Vine cucumbers can be successfully grown in vertical farming systems with proper support and trellising. Compact or bush varieties are preferred to manage the plant’s size and allow for vertical growth.
  7. Beans and Peas: Bush varieties of beans and peas are suitable for vertical farming. The plants can be trained to grow upward, and the vertical environment helps support the plants’ structure and pod development.
  8. Sprouts and Microgreens: Vertical farming is well-suited for cultivating sprouts and microgreens, which are young, nutrient-dense plants harvested at an early stage. These include broccoli sprouts, radish sprouts, pea shoots, sunflower shoots, and many others.
  9. Flowers and Ornamental Plants: Some vertical farming systems also grow flowers and ornamental plants, such as decorative foliage, flowering plants, or plants used in floral arrangements. These plants can add aesthetic value to vertical farms or be grown for commercial purposes.

These are just a few examples,vertical grow rack and the possibilities for crops in vertical farming are extensive. The choice of crops may vary based on factors such as market demand, growing conditions, space availability, and specific system design. Growers often select crops based on their profitability, suitability for controlled environments, and consumer preferences in their target market.

Which Plants Can be Grown in Vertical Farming

Vertical farming is a method of growing plants in vertically stacked layers or structures, often indoors or in controlled environments. This approach maximizes space utilization and allows for year-round cultivation. Various types of plants can be grown successfully in vertical farming systems. Here are some examples:

  1. Leafy Greens: Lettuce, spinach, kale, arugula, Swiss chard, and other leafy greens are popular choices for vertical farming. They have a short growth cycle, high yield potential, and don’t require extensive root systems.
  2. Herbs: Basil, mint, parsley, cilantro, and other herbs are well-suited for vertical farming. They thrive in compact spaces and can be grown hydroponically or aeroponically.
  3. Strawberries: Strawberries are ideal for vertical farming due to their compact size and vertical growth habit. They can be grown in towers or hanging baskets, making efficient use of vertical space.
  4. Microgreens: Microgreens are young, tender greens harvested at an early stage of growth. They include various plants like radish, broccoli, mustard, and many others. Microgreens have a short growth cycle, allowing for quick turnover and high productivity in vertical farming systems.
  5. Tomatoes: Certain varieties of tomatoes, such as determinate or bushy types, can be grown vertically using trellises or cages. These compact tomato plants can produce a good yield in vertical farming setups.
  6. Cucumbers: Compact or bush cucumbers are suitable for vertical farming. They can be trained to grow vertically using trellises or supported by strings or netting.
  7. Peppers: Some pepper varieties, like compact or dwarf cultivars, can be grown vertically. They can be trained to grow upward, providing higher yields in limited space.
  8. Flowers: Certain flowers, such as petunias, marigolds, and impatiens, can be grown in vertical farming setups for ornamental purposes. They add aesthetic appeal to indoor or vertical garden environments.
  9. Small Fruits: Some small fruit plants, like dwarf or miniaturized fruit trees, can be grown vertically in controlled environments. Examples include compact varieties of citrus trees, miniaturized apple trees, or columnar blueberries.

It’s important to consider the specific requirements of each plant, including light, temperature, humidity, and nutrient needs when implementing vertical farming systems. By optimizing these conditions and utilizing appropriate growing techniques like hydroponics or aeroponics, a wide range of plants can thrive in vertical farming environments.

Is a Grow Room Better Than a Grow Tent

Whether a grow room or a grow tent is better depends on your specific needs and circumstances. Here are some factors to consider when comparing the two:

  1. Space: A grow room typically offers more space compared to a grow tent. If you have a large-scale operation or want to grow a significant number of plants, a cannabis grow room might be more suitable. However, if you have limited space or want a more compact setup, a grow tent can be a viable option.
  2. Control: A grow room provides more control over environmental factors like temperature, humidity, and lighting. With a grow room, you have the flexibility to customize and fine-tune these conditions to meet the specific requirements of your plants. Grow tents, on the other hand, may have more limited control options but still offer a degree of control over the environment.
  3. Setup and Portability: Grow tents are generally easier and quicker to set up compared to a grow room. They usually come as complete kits with pre-installed ventilation ports, reflective interior surfaces, and other accessories. Grow tents are also more portable and can be easily disassembled and moved if needed. Grow rooms, on the other hand, require more planning, construction, and installation.
  4. Light Leakage and Reflection: Grow tents typically have a highly reflective interior surface, which helps maximize light efficiency by bouncing it back onto the plants. They are designed to minimize light leakage, which can be beneficial for light-sensitive plants like cannabis during their flowering stage. While grow rooms can also be made reflective, they may require additional materials and installation to achieve the same level of reflection and light containment.
  5. Cost: Grow tents tend to be more affordable compared to setting up a dedicated grow room. They offer a cost-effective solution,vertical grow system especially for small-scale or hobbyist growers. Grow rooms require more investment in construction materials, ventilation systems, and other equipment, which can be costlier upfront.
  6. Scalability: If you plan to expand your operation in the future, a grow room may offer more scalability. You can modify or expand the space as needed, allowing for increased plant capacity. Grow tents, while available in various sizes, have limitations in terms of their size and may not be as easily expandable.

Ultimately, the choice between a grow room and a grow tent depends on your specific requirements, available space, budget, and long-term goals. Consider factors such as scale, control, convenience, and cost to determine which option best suits your needs.

How to Increase the Yield of Your Grow Room

To increase the yield of your grow room and maximize your plant production, there are several strategies and techniques you can implement. Here are some tips to help you increase your grow room yield:

  1. Optimize Lighting: Ensure your plants receive adequate and appropriate lighting throughout their growth stages. Use high-quality grow lights that deliver the right spectrum and intensity for each phase of plant development. Consider adjusting light height, angles,plant growing rack or adding supplemental lighting to ensure uniform coverage and promote optimal photosynthesis.
  2. Enhance Air Circulation: Proper air circulation helps prevent stagnant air, reduces the risk of pests and diseases, and strengthens plant stems. Use oscillating fans or ventilation systems to improve air movement within your grow room. This can also help distribute heat evenly and maintain consistent temperature and humidity levels.
  3. Implement Plant Training: Train your plants by utilizing techniques such as topping, pruning, or using trellises. These methods help create a more uniform canopy, promote better light penetration, and encourage lateral growth. By controlling the plant’s shape and size, you can optimize the use of available space and light.
  4. Monitor and Optimize Nutrient Levels: Regularly check and maintain proper nutrient levels in your hydroponic or soil-based system. Ensure that the plants have access to essential macro and micronutrients required for their growth stages. Adjust nutrient solutions or soil amendments as needed based on plant requirements and nutrient deficiencies.
  5. Implement Proper Watering Practices: Avoid overwatering or underwatering your plants. Find the right balance by monitoring the moisture levels in your growing medium and adjusting watering frequency and volume accordingly. Maintaining proper hydration helps prevent stress, nutrient imbalances, and root issues.
  6. Consider CO2 Enrichment: Carbon dioxide (CO2) enrichment can enhance plant growth and yield in enclosed grow room environments. Monitoring and maintaining optimal CO2 levels (around 1000-1500 ppm) during the light cycle can promote photosynthesis and boost plant productivity. CO2 supplementation systems are available for this purpose.
  7. Maintain a Clean and Pest-Free Environment: Regularly clean and sanitize your grow room to prevent the buildup of pests, pathogens, and debris. Implement integrated pest management (IPM) strategies to monitor, prevent, and control pests effectively. Early detection and intervention help minimize damage and maximize plant health.
  8. Optimize Harvest Timing: Understand the ideal harvest time for each plant variety. Harvesting too early or too late can impact yield and quality. Follow the recommended harvest guidelines based on the specific crop,indoor vertical garden system and monitor indicators such as color, size, aroma, and trichome development.
  9. Keep Detailed Records: Maintain accurate records of your grow room activities, including nutrient schedules, lighting adjustments, pest and disease interventions, and plant performance. This information helps you identify trends, troubleshoot issues, and make informed decisions for future crops.

Remember that each plant species may have specific requirements, so it’s important to tailor your approach accordingly. Experimentation, observation, and continuous learning will help you fine-tune your techniques and increase your grow room yield over time.

How Much Food Does A Vertical Farm Produce

The amount of food produced by a vertical farm can vary depending on several factors, including the size of the farm, the technology used, the crop selection, and the cultivation methods employed. Vertical farms are designed to maximize growing space and optimize production efficiency in an indoor environment. Here are some considerations regarding food production in vertical farms:

  1. Crop selection: The type of crops grown in a vertical farm can have a significant impact on the total food production. Leafy greens, herbs, and microgreens are commonly grown in vertical farming systems due to their high yield potential and short growing cycles. These crops can be harvested multiple times throughout their growth cycle, allowing for continuous production.
  2. Vertical farming systems: The use of stacked layers or racks in vertical farms allows for increased growing space compared to traditional farming methods. Vertical farms can have multiple tiers or levels of growing platforms, increasing the potential yield per square foot of floor space.
  3. Growing methods: Vertical farms often utilize hydroponic or aeroponic systems that provide precise control over nutrient delivery, water, and environmental conditions. These controlled environments can optimize plant growth and increase yields compared to traditional soil-based farming methods.
  4. Lighting and energy efficiency: Vertical farms typically rely on artificial lighting systems, such as LED lights, to provide the necessary light spectrum for plant growth. LED technology has improved energy efficiency, reducing the cost and energy consumption associated with lighting.
  5. Continuous production: Vertical farms can implement staggered planting schedules and crop rotation techniques to ensure a continuous supply of fresh produce throughout the year. This enables year-round production and can increase overall food output.

It is challenging to provide an exact quantity of food produced by a vertical farm, as it can vary greatly depending on the factors mentioned above. However, vertical farming systems have the potential to produce significantly higher yields per square foot compared to traditional agriculture. By utilizing vertical space and optimizing environmental conditions, vertical farms can achieve higher productivity and potentially increase food production several times compared to conventional farming methods.

It’s important to note that the specific productivity of a vertical farm will depend on various factors, including the crop varieties chosen, the skill and expertise of the farm operators, the technology employed, and the efficiency of the overall system. Conducting a feasibility study and working with experts in vertical farming can help provide more accurate projections of food production potential based on specific project parameters.

Parental consistency and peer modeling were both significantly related to gateway drug use

The purpose of this exploratory study was to examine the association between gateway drug use and structural and social environmental variables by gender among a sample of Latino adolescents. The finding that neighborhoods closer to retailers are associated with less favorable neighborhood characteristics has multiple implications. First, it is a confirmation of recent studies, and it extends previous literature in a border county and geographical area with high proportions of Hispanic people. Second, to the extent that retailer data used in this study demonstrated associations consistent with previous findings in the literature it provides evidence of generalizability. The finding that distance to the nearest retailer was positively associated with gateway drug use is puzzling. Gateway drug use among girls was lowest in areas closest to alcohol and tobacco retailers, and remained unchanged for males. This difference observed by gender represents a new finding. One possible explanation relates to parental control and the differential factors that define the gender specific cultures of boys and girls. For example, girls in areas closest to retailers may come under greater parental control to counter anticipated effects of living in a high-risk environment i.e., parents monitor their daughters more than their sons. This may result in lower rates of gateway drug use for females that reside in areas regarded as high-risk. A similar finding was reported by Wahlgren et al. in which high-risk adolescents were less likely than low-risk adolescents to initiate smoking following a counseling intervention, ostensibly resulting from extra attention devoted to prevention efforts as a function of their high-risk status. Continuing with this logic,motel grow racks girls in high-risk neighborhoods, such as those close to retailers, may interact less with their environment.

Young males may not be subjected to the same level of parental control, and may enjoy support to interact freely with their nearby environment. A recent study by Norman et al. demonstrated differential rates of physical activity and interactivity between boys and girls with environmental features such as retailers. Given this context, young males would tend to access nearby retailers via walking in a manner that young females would not. Proximity to nearby retailers may have less influence on females if they are prevented from accessing them. Future studies should be designed to test parents’ differential control of males and females in high-risk environments. This study took place close to the border, one of high transition with one of the worlds’ busiest border crossing . The culture with respect to substance use is more accepting in Mexico compared to San Diego, CA . The increased risk for girls from cohort 2 to use gateway drugs may be an indication of this cross-border influence. Anecdotally, we believe more students from cohort 2 spent significant amounts of time in Mexico, some on a daily basis. Students returning to Mexico alone after school have considerable amounts of unmonitored time while in transit. It is plausible that parents of girls residing in Mexico and attending school in the US were more restrictive of their after school time. The only opportunity in such cases for risk behaviors to occur would be under the influence of the home environment, closer to the border if not in Mexico. This should be the focus of additional research. The design employed in this study enabled a conservative estimate of the relationship between gateway drug use and variables from the structural and social environment. Attempts were made to represent significant theoretical domains, but the analytical model employed here is under specified as many of the variables expected to influence adolescent’s behavior were not available e.g., family members’ use of gateway drugs. Furthermore, measures utilized in this cross-sectional study were not designed a-priori for the questions they are attempting to answer. For this reason, no direct measure of purchasing was included, and the conclusions of this study should not be misinterpreted to suggest that substances were necessarily purchased in areas of shortest distances from residence to the nearest retailer.

Ecological studies in the future should attempt to assess the direct exposure to retailers to increase the likelihood that relationships found at the ecological level reflect individual exposure to retailers. The distinct trends observed by gender provide general support for continued research in this area. The BEM emphasis for future studies includes additional focus on the potential modifying effect of modeling on retailer dispersion. Retailer presence may be nothing more than a marker for substance use modeling, including point-of-sale advertisements i.e., venue for modeling and observing substance use behaviors. Since marijuana is an illegal substance not sold commercially at retailers like alcohol and tobacco, including it as part of the dependent variable begins the process of evaluating effects of this modeling process on substances other than alcohol or tobacco. New models of environmental influences should account for these mediating and moderating processes, as well as other neighborhood features that provide the empirical evidence for modifying retailer policies, public transportation and other means of access to retail sources of alcohol, tobacco or marijuana and test such modifications effect on adolescents’ use of gateway drugs. Several aspects of this study define the significance to the current literature. First, this study employed a novel approach to explore the role of the built environment. Technology utilized in this study will become more precise and easier to use, and early studies based on this technology will provide important foundational work for future research. Second, this study continues important lines of research, with a segment of the population traditionally understudied and integrates an important area of emerging research, the structural environment. Each paper included in this dissertation employs a distinct methodological approach and aims to answer a different question. Notwithstanding their differences, they share a common theme: risk behaviors among Latino adolescents, specifically alcohol, tobacco and marijuana use. The purpose of Paper 1 was to identify correlates of alcohol and tobacco use. Correlate variables were selected based on the BEM and reflect constructs emphasized in learning theory.

The hierarchical model enabled a conservative exploration of the theoretical determinants of alcohol and tobacco use as additional variables were added to the model. After controlling for many other variables from the previous domains, items from the peer domain emerged as significant across both dependent variables, a direct confirmation of the theoretical approach being tested in the sequential regression technique. Paper 2 extended the outcomes to include marijuana use. This involved a creative approach to isolate discrepancies between reports of parents’ parenting behaviors among parent and child dyads, and then to compare the predictive strength of each data source with gateway drug use. Paper 2 fills a gap in the current literature. As reported by Spera , plenty of research has assessed parenting styles, but little has been replicated across cultures, ethnicities, and socioeconomic status groups . Most investigators studying parental influence recognize that adolescent and parental perspectives may be quite different ,rolling grow trays and most studies have relied on only one respondent in the family. The unique features of this study sample provided a venue for comparing the predictive validity between parent and adolescent reports and use of gateway drugs. It was pertinent to the overarching medication adherence community trial to query adolescent respondents and their primary caregiver with respect to parenting practices. Opportunities for comparisons of this variety are rarely available. Results reported here should have a distinct measurement implication. The finding that parental reports were not as predictive as adolescent reports is to be expected. However, interpreting the findings and their implications can be complicated, primarily because the true parenting values remain unknown. Notwithstanding, there are two meaningful implications resulting from these findings. First, the identification of in congruence between parent and adolescent reports and the difference in their predictive validity. These findings provide evidence that these two data sources cannot be considered equivalent. Second, these findings raise questions about the importance of perceptions. For example, adolescent perceptions about their parents’ parenting behaviors may be more important than parental perceptions about their own behaviors. Two possible rationales emerge: 1) parental reporting errors are uniformly overestimates and therefore less believable. It is unclear if parents can maintain objectivity in self-evaluating. They have a high vested interest in being seen as effective parents and their ability to report objectively may be compromised, and 2) adolescent behavioral practices may conform to the perceived desires of the parent according to how much the child perceives intense parental control, restriction, or involvement. Papers 1 and 2 were organized based on adaptations from a landmark publication by Hawkins et al. in which influential adolescent risk domains were identified.

These domains have been corroborated in subsequent research and included demographic related characteristics, family influence, school level influences, and peer influences. Variables used in analyses for papers 1 and 2 were selected based on the BEM, and then organized sequentially into risk domains discussed in the Hawkins paper. Notwithstanding, these risk behavior categories are likely non-inclusive of all risk behavior domains of significance, namely features in the built environment. At the time of their 1992 publication, Hawkins et al. could not have explored the built environment to the same degree of specificity that current methodologies allow. For example, variables from the built environment, like those included in paper 3, would have been much less precise in previous decades. Studies that utilize current technologies and contribute to the body of literature that incorporate such methodologies will be important in years to come. Paper 3 represents an exploratory study, the likes of which may help to shape the way researchers assess previously unstudied risk domains, i.e., the built environment. Despite methodological limitations associated with ecological analyses and the cross-sectional design, results from this study extend our current focus of environmental variables and suggest that we do so in the context of known social predictors of drug use. Findings from papers 1 and 2 were replicated for both males and females.The rational for creating separate regression models for males and females stems from evidence of gender differences regarding interactivity with the built environment. This rational was supported by demonstrating that distance to the nearest retailer was significant for females and not males. Interpreting these findings will almost assuredly be left to future research studies, but ideas are suggested in the last section of this document. The BEM guided this research. While non-prescriptive in nature, the model implicitly calls for the inclusion of variables from multiple domains. Some of these variables were available in complete form, some incomplete variables, and still some variables were unavailable. As a result, the analytical models were in general, probably under specified in the sense that I would have liked to have more, and better, variables that fit the theory. Inasmuch as the data were collected with only some of these analytical purposes in the design, many variables were not present, and still others could be improved upon. All measures in this study were self-report measures collected via interviews, save the variables from the built environment created using GIS software. Self-report measures have inherent sources of error, including recall bias and the opportunity for misrepresenting true values for reasons of social desirability. Notwithstanding their error, improvements could be made to improve their interpretability. For example, dichotomous measures of alcohol use on an ‘ever’ basis do not adequately discriminate use that was purely experimentation versus weekly or daily use of alcohol. While peer modeling emerged as a significant correlate of ever using alcohol , it is also possible that peers influence alcohol use at other frequencies too. That relationship is not clarified in this study. Furthermore, other contextual variables were not included, such as parental use of alcohol, tobacco, or marijuana. Parental use could mediate their adolescent’s to the extent that they model risk behaviors. In general, findings related to parenting should be interpreted in the context of the type and number of parenting items included in these studies. The items included in these papers represent a limited set of parenting items; they may or may not represent all of the parenting behaviors possible, and their generalizability is unclear. For example, joining parent groups at the child’s school may indicate a high level of involvement in other areas also. But the generalizability of this item, and others included in analyses, was not measured.