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This report introduces our winning solution of the real-robot phase of the Real Robot Challenge (RRC) 2022. The goal of this year's challenge is to solve dexterous manipulation tasks with offline reinforcement learning (RL) or imitation learning. To this end, participants are provided with datasets containing dozens of hours of robotic data. For each task an expert and a mixed dataset are provided. In our experiments, when learning from the expert datasets, we find standard Behavioral Cloning (BC) outperforms state-of-the-art offline RL algorithms. When learning from the mixed datasets, BC performs poorly, as expected, while surprisingly offline RL performs suboptimally, failing to match the average performance of the baseline model used for collecting the datasets. To remedy this, motivated by the strong performance of BC on the expert datasets we elect to use a semi-supervised classification technique to filter the subset of expert data out from the mixed datasets, and subsequently perform BC on this extracted subset of data. To further improve results, in all settings we use a simple data augmentation method that exploits the geometric symmetry of the RRC physical robotic environment. Our submitted BC policies each surpass the mean return of their respective raw datasets, and the policies trained on the filtered mixed datasets come close to matching the performances of those trained on the expert datasets.

This paper studies the problem of learning a control policy without the need for interactions with the environment; instead, learning purely from an existing dataset. Prior work has demonstrated that offline learning algorithms (e.g., behavioural cloning and offline reinforcement learning) are more likely to discover a satisfactory policy when trained using high-quality expert data. However, many real-world/practical datasets can contain significant proportions of examples generated using low-skilled agents. Therefore, we propose a behaviour discriminator (BD) concept, a novel and simple data filtering approach based on semi-supervised learning, which can accurately discern expert data from a mixed-quality dataset. Our BD approach was used to pre-process the mixed-skill-level datasets from the Real Robot Challenge (RRC) III, an open competition requiring participants to solve several dexterous robotic manipulation tasks using offline learning methods; the new BD method allowed a standard behavioural cloning algorithm to outperform other more sophisticated offline learning algorithms. Moreover, we demonstrate that the new BD pre-processing method can be applied to a number of D4RL benchmark problems, improving the performance of multiple state-of-the-art offline reinforcement learning algorithms.

This paper describes a deep reinforcement learning (DRL) approach that won Phase 1 of the Real Robot Challenge (RRC) 2021, and then extends this method to a more difficult manipulation task. The RRC consisted of using a TriFinger robot to manipulate a cube along a specified positional trajectory, but with no requirement for the cube to have any specific orientation. We used a relatively simple reward function, a combination of goal-based sparse reward and distance reward, in conjunction with Hindsight Experience Replay (HER) to guide the learning of the DRL agent (Deep Deterministic Policy Gradient (DDPG)). Our approach allowed our agents to acquire dexterous robotic manipulation strategies in simulation. These strategies were then applied to the real robot and outperformed all other competition submissions, including those using more traditional robotic control techniques, in the final evaluation stage of the RRC. Here we extend this method, by modifying the task of Phase 1 of the RRC to require the robot to maintain the cube in a particular orientation, while the cube is moved along the required positional trajectory. The requirement to also orient the cube makes the agent unable to learn the task through blind exploration due to increased problem complexity. To circumvent this issue, we make novel use of a Knowledge Transfer (KT) technique that allows the strategies learned by the agent in the original task (which was agnostic to cube orientation) to be transferred to this task (where orientation matters). KT allowed the agent to learn and perform the extended task in the simulator, which improved the average positional deviation from 0.134 m to 0.02 m, and average orientation deviation from 142{\deg} to 76{\deg} during evaluation. This KT concept shows good generalisation properties and could be applied to any actor-critic learning algorithm., Comment: This paper has been summited to Expert Systems: the Journal of Knowledge Engineering for reviewing. arXiv admin note: text overlap with arXiv:2109.15233

In this paper a self-biased current reference based on Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) Zero Temperature Coefficient (ZTC) condition is proposed. It can be implemented in any Complementary Metal-Oxide-Semiconductor (CMOS) fabrication process and provides another alternative to design current references. In order to support the circuit design, ZTC condition is analyzed using a MOSFET model that is continuous from weak to strong inversion, showing that this condition always occurs from moderate to strong inversion in any CMOS process. The proposed topology was designed in a 180 nm process, operates with a supply voltage from 1.4V to 1.8 V and occupies around 0.010mm2 of silicon area. From circuit simulations our reference showed a temperature coefficient (TC) of 15 ppm/oC from -40 to +85oC, and a fabrication process sensitivity of σ/μ = 4.5% for the current reference, including average process and local mismatch variability analysis. The simulated power supply sensitivity is estimated around 1%/V.

Emerging adulthood has been described as a difficult stage in life and may be particularly stressful for Hispanic emerging adults who are disproportionately exposed to adversity and chronic sociocultural stressors. To better prevent and treat depressive disorders among Hispanic emerging adults, more research is needed to identify and understand modifiable determinants that can help this population enhance their capacity to offset and recover from adversity and sociocultural stressors. As such, this study aimed to (1) examine the association between resilience and depressive symptoms among Hispanic emerging adults, and (2) examine the extent to which intrapersonal resources (e.g., mindfulness, distress tolerance, emotion regulation strategies) and interpersonal resources (e.g., family cohesion, social support) moderate the association between resilience and depressive symptoms. To examine these aims, 200 Hispanic emerging adults (ages 18-25) from Arizona (n = 99) and Florida (n = 101) completed a cross-sectional survey, and data were analyzed using hierarchical multiple regression and moderation analyses. Findings from the hierarchical multiple regression indicate that higher resilience was associated with lower depressive symptoms. Findings from the moderation analyses indicate that family cohesion, social support, and emotion regulation strategies (e.g., cognitive reappraisal and expressive suppression) functioned as moderators; however, mindfulness and distress tolerance were not significant moderators. Findings from this study add to the limited literature on resilience among Hispanics that have used validated measures of resilience. Furthermore, we advance our understanding of who may benefit most from higher resilience based on levels of intrapersonal and interpersonal resources.

End-to-end reinforcement learning techniques are among the most successful methods for robotic manipulation tasks. However, the training time required to find a good policy capable of solving complex tasks is prohibitively large. Therefore, depending on the computing resources available, it might not be feasible to use such techniques. The use of domain knowledge to decompose manipulation tasks into primitive skills, to be performed in sequence, could reduce the overall complexity of the learning problem, and hence reduce the amount of training required to achieve dexterity. In this paper, we propose the use of Davenport chained rotations to decompose complex 3D rotation goals into a concatenation of a smaller set of more simple rotation skills. State-of-the-art reinforcement-learning-based methods can then be trained using less overall simulated experience. We compare its performance with the popular Hindsight Experience Replay method, trained in an end-to-end fashion using the same amount of experience in a simulated robotic hand environment. Despite a general decrease in performance of the primitive skills when being sequentially executed, we find that decomposing arbitrary 3D rotations into elementary rotations is beneficial when computing resources are limited, obtaining increases of success rates of approximately 10% on the most complex 3D rotations with respect to the success rates obtained by HER trained in an end-to-end fashion, and increases of success rates between 20% and 40% on the most simple rotations., Comment: 5 pages, 3 figures, 3 tables, submitted to ICARA 2023

International audience; This work presents the design of an ultra-low-power frequency synthesizer based on a feedback loop composed by an improved version of the Factorial Delay Locked Loop (F-DLL). Its output frequency is controlled by a set of current-starved delay units tuned by a standard DLL feedback loop and a set of logic circuits to generate an RF output frequency proportional to the reference. The objective of this circuit is to achieve a power consumption in the micro-watt range to generate the desired output frequency proportional to the reference frequency between 1.5 and 2.0 GHz, being capable of supporting a wide range of input frequencies with a low phase noise (lower than -90 dBc/Hz at 1 MHz offset) and 370 μW of power consumption. In order to ensure the locking state of the feedback loop and to reduce the phase noise, a modification of the biasing circuit for the voltage controlled delay line (VCDL) is used to improve the linearity of the frequency response of the output using a complementary feedback loop architecture. The circuit was designed and fabricated using the 28 nm FDSOI technology from STMicroelectronics and the measurement results are presented.

Background The Acculturative Process and Context Framework (Ward & Geeraert, 2016) proposes that acculturative stressors influence psychological well-being over time. In fact, extant literature has linked bicultural stress with psychological functioning; yet, no studies have explored the causal dominance of bicultural stress. The purpose of the present study was to evaluate the directionality of prospective relations among bicultural stress and psychosocial functioning (i.e., depressive symptoms, hopefulness, and self-esteem) in Latinx immigrant adolescents across 5 waves. Method There were 303 Latinx adolescents who were recruited for this study from Los Angeles and Miami and were assessed across 5 waves at 6-month intervals. Adolescents were 14.50 years old on average (SD = .88) and 53.16% were male. Adolescents reported living in the United States for 2.07 years on average (SD = 1.87). A Random-Intercept Cross-Lagged Panel Model (RI-CLPM) was used to examine the between- and within-person relations among bicultural stress, depressive symptoms, hopefulness, and self-esteem in a comprehensive model. Results The comprehensive RI-CLPM including bicultural stress, depressive symptoms, hopefulness, and self-esteem exhibited excellent model fit. Between-person, trait-like relations among constructs ranged from small to large, as expected. Within-person, cross-lagged estimates among constructs were overall inconsistent, with some evidence that, within individuals, self-esteem influences later hopefulness. Conclusion Findings from this study indicate that the RI-CLPM is an effective strategy to examine bicultural stress and well-being processes among adolescents. There is a need for further research examining bicultural stress among Latinx immigrant youth, particularly within prevention and intervention studies. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

In this paper, we propose an ultra-low power compact 3-transistor voltage reference capable of operating at ultra-low supply voltages. The proposed circuit is based on the self-cascode MOSFET (SCM), which provides a reference voltage proportional to the threshold voltage ( $V_{T}$ ) difference of the two NMOS transistors that compose it. Reverse short-channel and narrow-width effects are explored to obtain such $V_{T}$ difference while using the same type of transistor. Ultra-low power operation and low line sensitivity is achieved by biasing the SCM with a zero- $V_{T}$ (native) transistor, also leading to an area efficient design. To show its versatility, three versions of the proposed circuit were fabricated in a standard 0.13- $\mu \text{m}$ CMOS process. Measurement performed over five samples showed an average temperature coefficient of 150–1500 ppm/°C. Minimum supply voltages of 0.12–0.4 V was observed while providing reference voltages around tens of mV. The proposed circuits consume 0.33–50 pW at room temperature and minimum supply voltage. The occupied area for any version is less than 0.0012 mm2.

Bimanual tasks involve the coordination of both arms, which often offers redundancy in the ways a task can be completed. The distribution of control across limbs is often considered from the perspective of handedness. In this context, although there are differences across dominant and nondominant arms during reaching control ( Sainburg 2002 ), previous studies have shown that the brain tends to favor the dominant arm when performing bimanual tasks ( Salimpour and Shadmehr 2014 ). However, biomechanical factors known to influence planning and control in unimanual tasks may also generate limb asymmetries in force generation, but their influence on bimanual control has remained unexplored. We investigated this issue in a series of experiments in which participants were instructed to generate a 20-N force with both arms, with or without perturbation of the target force during the trial. We modeled the task in the framework of optimal feedback control of a two-link model with six human-like muscles groups. The biomechanical model predicted a differential contribution of each arm dependent on the orientation of the target force and joint configuration that was quantitatively matched by the participants’ behavior, regardless of handedness. Responses to visual perturbations were strongly influenced by the perturbation direction, such that online corrections also reflected an optimal use of limb biomechanics. These results show that the nervous system takes biomechanical constraints into account when optimizing the distribution of forces generated across limbs during both movement planning and feedback control of a bimanual task. NEW & NOTEWORTHY Here, we studied a bimanual force production task to examine the effects of biomechanical constraints on the distribution of control across limbs. Our findings show that the central nervous system optimizes the distribution of force across the two arms according to the joint configuration of the upper limbs. We further show that the underlying mechanisms influence both movement planning and online corrective responses to sudden changes in the target force.

Objectives To examine trajectories of adolescent psychosocial risk - drug use, depressive and anxiety symptoms, and violence victimization and observation - and the longitudinal relationship between psychosocial risk trajectories during adolescence and HIV risk behaviors in adulthood. Methods The 18-year longitudinal study was conducted from September 1994 through May 2013, in Michigan. Eight hundred and fifty predominantly (80%) African-American adolescents completed demographics and measures of drug use, depressive and anxiety symptoms, violence victimization and observation at Times 1-4, sexual risk behaviors at Times 5 and 6, and social conditions (i.e. family, peer, and community-level factors) between 14.9 and 32.0 years of age. Results Growth mixture modeling revealed two trajectories of psychosocial risk factors which can be characterized as a syndemic index: high-frequency and low-frequency. The high-frequency class was more likely to report HIV risk behaviors, including condomless sex at last sexual intercourse with their primary and secondary partner, sexual intercourse with someone they just met, at least four sexual partners, and licit and illicit drug use prior to sexual intercourse at Time 5 (mean age 23.1). At Time 6 (mean age 32.0), the high-frequency class was more likely to report sexual intercourse with someone they just met and at least four sexual partners, relative to the low-frequency class. In addition, the high-frequency class was linked to peer and family-level indicators of social conditions. Conclusion A syndemic index comprised of co-occurring psychosocial risk factors in adolescence seem to have lasting effects on the vulnerability to engage in HIV risk behaviors in emerging adulthood, some of which extend into young adulthood.

In this paper, a self-biased temperature-compensated CMOS voltage reference operating at picowatt-level power consumption is presented. The core of the proposed circuit is the self-cascode MOSFET (SCM) and two variants are explored: a self-biased SCM (SBSCM) and a self-biased NMOS (SBNMOS) voltage reference. Power consumption and silicon area are remarkably reduced by combining subthreshold operation with a self-biased scheme. Trimming techniques for both circuits are discussed aiming at the reduction of the process variations impact. The proposed circuits were fabricated in a standard 0.18- $\mu \text{m}$ CMOS process. Measurement results from 24 samples of the same batch show that both circuits herein proposed can operate at 0.45/0.6 V minimum supply voltage, consuming merely 55/184 pW at room temperature. Temperature coefficient (TC) around 104/495 ppm/°C across a temperature range from 0 to 120 °C was measured. Employment of a trimming scheme allows a reduction of the average TC to 72.4/11.6 ppm/°C for the same temperature range. Both variants of the proposed circuit achieve a line sensitivity of 0.15/0.11 %/V and a power supply rejection better than −44/−45 dB from 10 to 10 kHz. In addition, SBSCM and SBNMOS prototypes occupy a silicon area of 0.002 and 0.0017 mm2, respectively.

Electromagnetic interference (EMI) disturbances coupled in the power supply of voltage and current references can severely degrade their performance, due to its finite power supply rejection (PSR). The design of a 90-dB PSR 4-dBm EMI-resistant NMOS-only voltage reference is herein presented. The voltage reference is designed based on the zero-temperature-coefficient transistor operating point. The high PSR is obtained using zero- $V_{T}$ transistors as active loads in the open and feedback loop of the circuit. Two versions, using standard $V_{T}$ and low-power $V_{T}$ transistors, were designed in a 130-nm CMOS process. Both are designed using the same thermal compensation principle. The circuits occupy 0.014 and 0.006 mm $^{2}$ of silicon area while consuming around 1.15 and 0.156 $\mu$ W at 27 $^\circ$ C, respectively. Postlayout simulations present a reference voltage of 206 and 450 mV with an average temperature coefficient of 321 and 86 ppm/ $^\circ$ C (1000 samples), under a temperature range from $-$ 55 to 125 $^\circ$ C. An EMI source of 4 dBm (1 $\text{V}_{\text{pp}}$ ) injected in the power supply, according to the direct power injection standard, yields $-$ 0.17% and $-$ 0.1 ${\%}$ of the maximum dc shift and 822 and 950 $\mu \text{V}_{\text{pp}}$ of the maximum peak-to-peak ripple for the standard $V_{T}$ and low-power $V_{T}$ implementations, respectively.

Objectives. To examine trends in and correlates of fighting and violence among youths from the 3 largest racial/ethnic groups in the United States. Methods. We derived race/ethnicity-specific prevalence estimates for fighting, group fighting, and attacks with intent to harm from the National Survey on Drug Use and Health, a population-based study of youths aged 12 to 17 years. Results. The prevalence of youth fighting and violence decreased significantly in all racial/ethnic groups over the study period (2002–2014), dropping from a high of 33.6% in 2003 to a low of 23.7% in 2014, reflecting a 29% decrease in the relative proportion of young people involved in these behaviors. However, there was also a clear severity gradient in which year-by-year point estimates for fighting and violence were consistently highest among non-Hispanic African American youths, followed by Hispanic and then non-Hispanic White youths. Conclusions. Although fighting and violence are on the decline among young people in general and across racial/ethnic subgroups, there is a stable pattern of disparities in youth involvement in these behaviors.

Social capital plays an important role in sexual and reproductive health among youth, yet few measures to assess this concept have been developed and tested for this population. We developed and examined the factor structure of the Brief Social Capital for Youth Sexual and Reproductive Health Scale. Drawing on the empirical literature, we identified item content to assess an overall construct of social capital in relationship to youth’s sexual and reproductive health, including condom self-efficacy, civic engagement, and adult and community support. We conducted exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) with a sample of 200 youth, predominately low-income and ethnic minority in Denver, Colorado. EFA with geomax rotation yielded a three-factor solution. CFA provided an adequate model fit with acceptable standardized factor loadings. This study provides a validated measure for future research to further examine social capital and youth sexual and reproductive health.

Complex Regional Pain Syndrome (CRPS) is characterized by pain, motor and inflammatory symptoms usually affecting one limb. Cognitive difficulties have been reported to affect patients’ ability to represent, perceive and use their affected limb. It is debated whether these difficulties result from deficits in controlling goal-directed movements in space or from a learned strategy to protect the affected limb. In order to dissociate the two hypotheses, patients with upper-limb CRPS were asked to move with their unaffected hand towards visual targets projected at different positions on a horizontal semi-reflexive mirror. By means of a robotic handle placed below the screen, they were asked to move a cursor, to reach and cross lines at their estimated midpoint. In some of the stimulation series, the affected hand was placed below the mirror so that some lines appeared projected onto that hand. Vision of the hands and the robotic handle was preserved or prevented by opening or closing a shutter below the mirror. Lines were displayed on the mirror according to which part of the body was affected (ispi- vs. contralateral) and the actual position of the affected hand (inside vs. outside the workspace). Comparatively to control participants, CRPS patients generally biased their estimation by bisecting the lines towards their left side, irrelative of which part of the body was affected and the position of the affected hand, both in ipsi- and contralateral space, with only a few exceptions. Our results are in line with previous studies having described a visuospatial deficit in CRPS patients and discard the explanation of observed symptoms in terms of learned nonuse strategies, as only the unaffected hand was used to perform the task. It is suggested that CRPS patients can display difficulties to perform tasks requesting visuo-motor coordination, reflecting the complex cortical reorganization occurring in CRPS., SCOPUS: ar.j, info:eu-repo/semantics/published

A voltage reference based on MOSFETs operated under Zero Temperature Coefficient (ZTC) bias is proposed. The circuit operates in a power supply voltage range from 0.3 V up to 1.2 V and outputs three different reference voltages using Standard- $V_{T}$ (SVT), Low- $V_{T}$ (LVT), and Zero- $V_{T}$ (ZVT) MOS transistors biased near their ZTC point by a single PTAT current reference. Measurements on 15 circuit samples fabricated in a standard 0.13- $\mu \text{m}$ CMOS process show a worst-case normalized standard deviation $(\sigma /\mu)$ of 3% (SVT), 5.1% (LVT) and 10.8% (ZVT) respectively with a 75% of confidence level. At the nominal supply voltage of 0.45 V, the measured effective temperature coefficients (TCeff) range from 140 to 200 ppm/°C over the full commercial temperature range. At room temperature (25 °C), line sensitivity in the ZVT VR is just 1.3%/100 mV, over the whole supply range. The proposed reference draws around 5 $\mu \text{W}$ and occupies 0.014 mm2 of silicon area.

The linearity and noise requirements in multi-band multi-standard applications make the design of RF CMOS circuits a very challenging task. A low noise transconductance amplifier (LNTA) in 130 nm CMOS technology that operates between 1 and 6 GHz is presented. The LNTA is based on a shunt-feedback (SFB) amplifier with current-reuse scheme and employing the noise-canceling technique used in low-noise amplifier designs for wideband input matching. Two versions of the LNTA were designed in a 130 nm CMOS process and occupy 0.038 and 0.014 mm2 of silicon area while consuming just 9.1 and 7.94 mW, respectively. The second version is an inductorless, smaller, and optimized version of the first one. Post-layout simulations in the temperature range of ź40 to 125 °C show a good trade-off between noise and power-consumption across the frequency span with an average noise figure of 3.8 dB and a minimum transconductance of 41.5 mS over the entire band. Performance variations were estimated at 2 GHz with Monte Carlo analysis.

Human Immunodeficiency Virus (HIV)/sexually transmitted infection (STI) risk behaviors among adolescents remain significant public health concerns. Shifts in policy and advances in technology provide opportunities for researchers and clinicians to deliver and evaluate mobile-health (mHealth) prevention programs in primary care, however, research is limited. This study assessed the usability and acceptability of Storytelling 4 Empowerment-a mHealth HIV/STI and drug abuse preventive intervention app-among adolescents in primary care. Informed by principles of community-based participatory research, we recruited a purposive sample of 30 adolescents from a youth-centered community health care clinic in Southeast Michigan. The study sample is primarily African American and female. Adolescents who participated in the Storytelling 4 Empowerment intervention assessed its usability and acceptability, and self-reported their HIV/STI risk behaviors. We used a multiple-methods approach. Adolescents reported high acceptability of the content, process, and format of Storytelling 4 Empowerment, as evidenced by qualitative data and mean scores from the Session Evaluation Form for the HIV/STI and Alcohol/Drug content, overall Storytelling 4 Empowerment intervention, and Client Satisfaction Questionnaire-8. Findings indicate that Storytelling 4 Empowerment is acceptable among adolescents in primary care. A next step is to examine the effect of Storytelling 4 Empowerment on adolescent sexual risk and drug use behaviors and HIV/STI testing.

We examined the effects of family functioning trajectories on sexual risk behaviors and STI in adolescents. A sample of 850 predominantly (80%) Black adolescents from Michigan, United States, was assessed at baseline, 12, 24, and 36 months postbaseline. Adolescents were from working-class families with a mean age of 14.9 years (SD = .64, Range = 13.9 to 16.9) at baseline. Participants completed measures of family functioning at each time point. At 36 months postbaseline, levels of sexual risk behaviors, including sex initiation, unprotected sex, and alcohol or drug use before last sexual intercourse, and STIs were assessed. Latent class growth analysis (LCGA) yielded 4-class solutions for family conflict and parent support. Adolescents with high or increasing family conflict trajectories, and low or decreasing family support trajectories, were at relatively greater risk of sexual risk behaviors and STIs. Yet, the additional trajectories differ across outcomes highlighting the complexities of the role of family functioning on sexual risk behaviors and STIs over time. Multiple Group LCGA indicate some findings vary as a function of gender. (PsycINFO Database Record

Drawing from a theory of bicultural family functioning two models were tested to examine the longitudinal effects of acculturation-related variables on adolescent health risk behaviors and depressive symptoms (HRB/DS) mediated by caregiver and adolescent reports of family functioning. One model examined the effects of caregiver-adolescent acculturation discrepancies in relation to family functioning and HRB/DS. A second model examined the individual effects of caregiver and adolescent acculturation components in relation to family functioning and HRB/DS. A sample of 302 recently immigrated Hispanic caregiver-child dyads completed measures of Hispanic and U.S. cultural practices, values, and identities at baseline (predictors); measures of family cohesion, family communications, and family involvement six months post-baseline (mediators); and only adolescents completed measures of smoking, binge drinking, inconsistent condom use, and depressive symptoms one year post-baseline (outcomes). Measures of family cohesion, family communications, and family involvement were used to conduct a confirmatory factor analysis to estimate the fit of a latent construct for family functioning. Key findings indicate that (a) adolescent acculturation components drove the effect of caregiver-adolescent acculturation discrepancies in relation to family functioning, (b) higher levels of adolescent family functioning were associated with less HRB/DS, whereas higher levels of caregiver family functioning were associated with more adolescent HRB/DS, (c) and only adolescent reports of family functioning mediated the effects of acculturation components and caregiver-adolescent acculturation discrepancies on HRB/DS.

Background Preventing and reducing substance use disorders, sexually transmitted infections (STIs)/HIV, and teen pregnancy, and the associated risk behaviors (ie, substance use and sexual risk behaviors) among youth remain public health priorities in the United States. Equally important is improving the uptake of STI/HIV testing among the youth. Mobile health (mHealth) apps may be a solution to ameliorate these public health concerns; however, few mHealth preventive interventions have demonstrated efficacy in reducing substance use or sexual risk behaviors or improving the uptake of STI/HIV testing among the youth, particularly in clinic settings. Objective This small-scale study aimed to examine the feasibility of conducting a pilot randomized controlled trial (RCT). We evaluated the effects of Storytelling 4 Empowerment (S4E), relative to enhanced usual practice, on the potential mechanisms by which behavior change occurs, namely clinician-youth risk communication, prevention knowledge, and substance use and sexual risk refusal self-efficacy. We also assessed the ability to measure targeted outcomes of past 30-day substance use (ie, alcohol, tobacco, and other drug use), condomless sex, and alcohol or drug use before sex, as well as the uptake of STI/HIV testing. Methods Employing community-based participatory research principles, 50 youths aged 13 to 21 years were recruited from a youth-centered community health clinic in Southeast Michigan, randomized sequentially to either S4E or enhanced usual practice, and assessed at baseline, immediately postintervention, and 30 days postintervention. S4E consists of 3 modules, including alcohol and drug use, tobacco, and STI/HIV. Results Relative to youth in the enhanced usual practice group, S4E participants demonstrated higher youth-clinician risk communication (mean 3.22, SD 1.67) and increases in prevention knowledge (∆ score mean 0.36, SD 0.51) and self-efficacy (∆ score mean 0.16, SD 0.47). In addition, youth in the S4E group showed reductions in the proportions of past 30-day overall substance use (Cohen h=0.71, 95% CI 0.15 to 1.27), as well as past 30-day alcohol (Cohen h=0.71, 95% CI 0.15 to 1.27), tobacco (Cohen h=0.17, 95% CI −0.39 to 0.73), and drug use (Cohen h=1.28, 95% CI 0.72 to 1.84). The results also suggest a reduction in the proportion of youths who reported past 30-day condomless sex (Cohen h=0.18, 95% CI −0.38 to 0.74) and alcohol use before sex (Cohen h=0.44, 95% CI −0.12 to 1.00). Finally, the findings also demonstrated an increase in the proportion of youths who reported STI/HIV testing over time (Cohen h=0.16, 95% CI −0.39 to 0.72). Conclusions The findings suggest the feasibility of a small-scale pilot RCT. S4E demonstrated shifts in the hypothesized direction, reducing substance use, sexual risk behaviors, and improving the uptake of STI/HIV testing among youth in a clinic setting. The findings suggest that a larger RCT may be warranted. Trial Registration ClinicalTrails.gov NCT03855410, https://clinicaltrials.gov/ct2/show/NCT03855410.

International audience; This paper presents the relevant aspects of the design of an ultra-low-power frequency synthesizer based on the combination of two feedback loops, a Phase-Locked Loop (PLL) acting together with a Delay-Locked Loop (DLL) to perform fine and coarse tuning of the desired output frequency, respectively. The objective of the circuit is to achieve a power consumption lower than 100 µA to generate a 2.5 GHz output frequency, improving the poor phase-noise of ring oscillators with the usage of the DLL circuit as an auxiliary feedback loop to cancel the phase noise and adjusting the VCO frequency through the body bias feature, available in the 28 nm FDSOI technology from STMicroelectronics.

Background: HIV/sexually transmitted infections (STIs) and drug abuse remain significant public health concerns in the United States, and African American and Hispanic youth are disproportionately affected. Although technology-based interventions are efficacious in preventing and reducing HIV/STI and licit/illicit drug use behaviors, relatively little is known regarding the state of the science of these interventions among African American and Hispanic youth. Objective: The aim of this review is to identify and examine randomized controlled trials (RCTs) of technology-based HIV/STI and/or drug abuse preventive interventions for African American and Hispanic youth. Methods: We searched electronic databases (ie, PubMed, Proquest, PsycINFO, Ebscohost, Google Scholar) to identify studies between January 2006 and October 2016. RCTs of technology-based interventions targeting African American and Hispanic youth HIV/STI risk behaviors, including sexual risk, licit and illicit drug use, and HIV/STI testing were included. Results: Our search revealed a total of three studies that used an RCT design and included samples comprised of >50% African American and/or Hispanic youth. The follow-up assessments ranged from two weeks to six months and the number of participants in each trial ranged from 72 to 141. The three interventions were theory-driven, interactive, and tailored. The long-term effects of the interventions were mixed, and outcomes included reductions in sex partners, licit drug use, and condomless anal sex acts. Conclusions: Although technology-based interventions seem promising in the prevention of HIV/STI and drug abuse among African American and Hispanic youth, more research is needed. [JMIR Public Health Surveill 2017;3(4):e96]

Despite policy changes related to the use and distribution of marijuana in cities and states across the country, few studies have examined changes in disapproval and use of marijuana among American youth.To examine trends in disapproval and use of marijuana among adolescents and young adults in the United States.We employed nationally representative data spanning the period of 2002-2013. Analyses were based on self-reported measurements from 105,903 younger adolescents (aged 12-14); 110,949 older adolescents (aged 15-17); and 221,976 young adults (aged 18-25).Between 2002 and 2013 the proportion of adolescents aged 12-14 reporting "strong disapproval" of marijuana use initiation increased significantly from 74.4-78.9%. Concurrently, a significant decrease in past 12-month marijuana use (OR = 0.98, 95% CI = 0.97-0.99) was observed among younger adolescents. No significant trend was observed for marijuana use disapproval among adolescents aged 15-17 between 2002 and 2013. Yet a significant (OR = 0.99, 95% CI = 0.98-0.99) decrease in the past 12-month marijuana use was observed (2002 = 26.2%, 2013 = 21.9%) among this group. Among young adults (aged 18-25), a substantial decrease - from 40.5% in 2002 to 22.6% in 2013 - was observed in the proportion reporting "strong disapproval" of marijuana use initiation; however, increases in the past 12-month use were relatively small among young adults (Δ = 2.21) but statistically significant (OR = 1.02, 95% = 1.01-1.02).Changes are underway in the perception and use of marijuana among American youth. However, changes differ in important ways among youth from distinct developmental subgroups.

We sought to determine the extent to which initial levels and over-time trajectories of cultural stressors (discrimination, negative context of reception, and bicultural stress) predicted well-being, internalizing symptoms, conduct problems, and health risk behaviors among recently immigrated Hispanic adolescents. Addressing this research objective involved creating a latent factor for cultural stressors, establishing invariance for this factor over time, estimating a growth curve for this factor over time, and examining the effects of initial levels (intercepts) and trajectories (slopes) of cultural stressors on adolescent outcomes.A sample of 302 recently immigrated Hispanic adolescents in Miami (median of 1 year in the United States at baseline) and Los Angeles (median of 3 years in the United States at baseline) was recruited from public schools and assessed six times over a 3-year period.Perceived discrimination, context of reception, and bicultural stress loaded onto a latent factor at each of the first five timepoints. A growth curve conducted on this factor over the first five timepoints significantly predicted lower self-esteem and optimism, more depressive symptoms, greater aggressive behavior and rule breaking, and increased likelihood of drunkenness and marijuana use.The present results may be important in designing interventions for Hispanic immigrant children and adolescents, including those within the present wave of unaccompanied child migrants. Results indicate targeting cultural stressors in interventions may have potential to improve well-being and decrease externalizing behaviors and substance use within this population.

This study examined longitudinal effects of adolescent and parent cultural stress on adolescent and parent emotional well-being and health behaviors via trajectories of adolescent and parent family functioning. Recent immigrant Latino adolescents (Mage = 14.51) and parents (Mage = 41.09; N = 302) completed measures of these constructs. Latent growth modeling indicated that adolescent and parent family functioning remained stable over time. Early levels of family functioning predicted adolescent and parent outcomes. Baseline adolescent cultural stress predicted lower positive adolescent and parent family functioning. Latent class growth analyses produced a two-class solution for family functioning. Adolescents and parents in the low family functioning class reported low family functioning over time. Adolescents and parents in the high family functioning class experienced increases in family functioning.

A nano-ampere current reference with temperature compensation operating is presented. The reference current is generated biasing a zero-VT transistor near its Zero-temperature coefficient (ZTC) point. Two versions were implemented in a 180 nm CMOS process. Both are designed using the same thermal compensation principle, but the second version uses an auxiliary circuit to compensate process variation. The circuits occupy 0.01 and 0.018 mm2 of silicon area while consuming around 30.5 and 122 nW at 27° C, respectively. Post-layout simulations present a reference current of 10.86 and 10.95 nA with a average temperature coefficient of 108 and 127 ppm/°C (100 Samples), under a temperature range from −20 to 120 °C, and a line sensitivity of 0.54 and 0.86 %/V at 0.9 V to 1.8 V of supply voltage, respectively.

Despite the profound impact that intrafamilial stressors, including parent – adolescent acculturation discrepancies, may have on Latino adolescent behavioral and mental health, this line of research remains underdeveloped. The purpose of this study is to obtain rich descriptions from Latino adolescents of the most salient intrafamilial stressors. The authors employ focus group methodology with a grounded theory approach. A total of 25 focus groups were conducted with 170 Latino adolescents in the Northeast and Southwest United States. Findings indicate that Latino adolescents experience significant stressors related to parent – adolescent acculturation discrepancies. From this qualitative study the authors derive a series of testable hypotheses aimed at fully understanding the role of parent – adolescent acculturation discrepancies on Latino adolescent behavioral and mental health and informing the development of culturally responsive preventive interventions for this population.