Precursor Engineering of Solution-Processed Sb2 S3 Solar Cells.

Antimony-based chalcogenides have emerged as promising candidates for next-generation thin film photovoltaics. Particularly, binary Sb2 S3 thin films have exhibited great potential for optoelectronic applications, due to the facile and low-cost fabrication, simple composition, decent charge transport and superior stability. However, most of the reported efficient Sb2 S3 solar cells are realized based on chemical bath deposition and hydrothermal methods, which require large amount of solution and are normally very time-consuming. In this work, Ag ions are introduced within the Sb2 S3 sol-gel precursors, and effectively modulated the crystallization and charge transport properties of Sb2 S3 . The crystallinity of the Sb2 S3 crystal grains are enhanced and the charge carrier mobility is increased, which resulted improved charge collection efficiency and reduced charge recombination losses, reflected by the greatly improved fill factor and open-circuit voltage of the Ag incorporated Sb2 S3 solar cells. The champion devices reached a record high power conversion efficiency of 7.73% (with antireflection coating), which is comparable with the best photovoltaic performance of Sb2 S3 solar cells achieved based on chemical bath deposition and hydrothermal techniques, and pave the great avenue for next-generation solution-processed photovoltaics.

Patterns of Substance Use and Associations with Mental, Physical, and Social Functioning: A Latent Class Analysis of a National Sample of U.S. Adults Ages 30-80.

OBJECTIVE: Trends show increased substance use among adults, yet little research on general population samples has examined differential patterns of licit and illicit substance use that can inform prevention and treatment efforts. This study identifies distinct patterns (classes) of substance use among 30- to 80-year olds, identifies demographic subgroups with the highest probability of class memberships, and compares classes on key indicators of functioning. Method: Participants (n = 1,877) were from the RAND American Life Panel. Online survey measures included current alcohol, tobacco, cannabis, and nonmedical prescription drug use, as well as mental, physical, and social functioning. Results: Latent class analysis identified four classes: "Lighter Drinking" (46.6%), "Abstaining" (33.7%), "Heavy Drinking with Cigarette/Cannabis Use" (17.1%), and "Cigarette Smoking with Prescription Drug/Cannabis Use" (2.6%). Of these classes, "Cigarette Smoking with Prescription Drug/Cannabis Use" reported the worst mental and physical functioning, and greater loneliness than the "Lighter Drinking" class. "Heavy Drinking with Cigarette/Cannabis Use" reported worse mental and physical functioning than the "Lighter Drinking" class and less social support than the "Lighter Drinking" and "Abstaining" classes. The "Abstaining" class reported consistently worse functioning than the "Lighter Drinking" class. Both polysubstance use classes were associated with younger age, less education, and lower income, and heavy drinking polysubstance use was associated with being male and unmarried. Conclusions: Although lighter drinking was the most common pattern, 20% of adults were classified into two polysubstance use classes associated with poorer functioning. Targeted efforts may be needed to reach certain subgroups of adults who are particularly susceptible to polysubstance use.

High-resolution restoration of 3D structures from widefield images with extreme low signal-to-noise-ratio.

Four-dimensional fluorescence microscopy--which records 3D image information as a function of time--provides an unbiased way of tracking dynamic behavior of subcellular components in living samples and capturing key events in complex macromolecular processes. Unfortunately, the combination of phototoxicity and photobleaching can severely limit the density or duration of sampling, thereby limiting the biological information that can be obtained. Although widefield microscopy provides a very light-efficient way of imaging, obtaining high-quality reconstructions requires deconvolution to remove optical aberrations. Unfortunately, most deconvolution methods perform very poorly at low signal-to-noise ratios, thereby requiring moderate photon doses to obtain acceptable resolution. We present a unique deconvolution method that combines an entropy-based regularization function with kernels that can exploit general spatial characteristics of the fluorescence image to push the required dose to extreme low levels, resulting in an enabling technology for high-resolution in vivo biological imaging.

Befriending Risky Peers: Factors Driving Adolescents' Selection of Friends with Similar Marijuana Use.

Adolescents often befriend peers who are similar to themselves on a range of demographic, behavioral, and social characteristics, including substance use. Similarities in lifetime history of marijuana use have even been found to predict adolescent friendships, and we examine whether this finding is explained by youth's selection of friends who are similar on a range of more proximate, observable characteristics that are risk factors for marijuana use. Using two waves of individual and social network data from two high schools that participated in Add Health (N = 1,612; 52.7% male), we apply longitudinal models for social networks to test whether or not several observable risky attributes (psychological, behavioral, and social) predict adolescent friendship choices, and if these preferences explain friend's similarities on lifetime marijuana use. Findings show that similarities on several risk factors predict friendship choices, however controlling for this, the preference to befriend peers with a similar history of marijuana use largely persists. The results highlight the range of social selection processes that lead to similarities in marijuana use among friends and larger peer groups, and that also give rise to friendship groups whose members share similar risk factors for substance use. Friends with high "collective risk" are likely to be important targets for preventing the onset and social diffusion of substance use in adolescents.

An ultrafast surface-bound photo-active molecular motor.

We report the synthesis and surface attachment of an ultrafast light-driven rotary molecular motor. Transient absorption spectroscopy revealed that the half-life of the rate determining thermal step of the rotary cycle in solution is 38 ± 1 ns, the shortest yet observed, making this the fastest molecular motor reported. Incorporation of acetylene legs into the structure allowed the motors to be grafted to azide-modified quartz and silicon substrates using the "click" 1,3-dipolar cycloaddition reaction.

Health-related social control among U.S. adults ages 30-80: Associations with alcohol use over four years.

Health-related social control (HRSC) includes efforts to regulate or influence others' health behaviors and is an important way interpersonal relationships can affect individual-level health. This study used egocentric network data to describe the size and composition of HRSC networks, identify trajectories of HRSC receipt, and examine how HRSC is related to binge drinking and alcohol-related problems. Data come from a U.S. nationally representative sample of 1235 adults age 30 and older (baseline mean age = 52, 52% female, 64% White) who completed four annual surveys between 2019 and 2022. On average, 30% of adults' network members were HRSC agents who told or reminded them to do things to protect their health. At baseline, 50% of respondents identified a spouse/partner as a HRSC agent, 56% a relative, 46% a friend, and 12% someone else. Respondents' relationships with HRSC agents were generally strong, 93% of agents were described as people "whose opinion matters," and only 10% were described as hassling or making life difficult for the respondent. Growth mixture modeling identified five trajectories of HRSC receipt over the four-year period: Stable High (36% of sample), Stable Moderate (47%), Stable Low (14%), Decreasing (2%), and Increasing (2%). Binge drinking was relatively consistent for the three Stable HRSC classes (ranging from 11% to 15% of individuals), decreased steadily for the Increasing HRSC class (32%-16%), and fluctuated for the Decreasing HRSC class (decreasing from 10% to 2%, then increasing to 8%). For alcohol problems, the Increasing HRSC class showed the largest increase (2%-21%) before dropping to near-baseline levels (4%), whereas the Decreasing HRSC class fluctuated during the first three waves followed by no individuals reporting alcohol problems at the last wave. Results highlight the importance of examining heterogeneity in adults' HRSC experiences because of its implications for understanding social influences on health-related behaviors.

Peer influence and selection processes in adolescent smoking behavior: a comparative study.

INTRODUCTION: Adolescent smoking studies find evidence of active peer influence and selection processes. However, studies have shown that these processes operate differently depending on context. This study uses SIENA to model coevolutionary processes between smoking and changes in friendship ties, comparing two high schools in which data were collected in identical fashion to explore influence and selection mechanisms with respect to current smoking, and smoking levels. METHODS: This is a longitudinal survey with 2 waves of data. In-home surveys were conducted with students from 2 large high schools in the United States: a West Coast school, and a Midwestern school. Participants were consented students in 10th and 11th grades at the first wave of data collection. The primary measures were self-reported smoking behavior and friendship nominations. RESULTS: There is evidence of influence and selection in both schools for adolescents' smoking status (1 = any smoking) and for level of smoking. CONCLUSIONS: These models reflect great similarities in influence and selection processes across schools for different smoking behaviors. However, smoking prevalence may impact the exact mechanisms by which influence and selection operate. Researchers should consider smoking interventions with independent modules addressing different selection and influence processes, implemented based on contextual factors such as the prevalence of smoking.

Kinetic analysis of synaptonemal complex dynamics during meiosis of yeast Saccharomyces cerevisiae reveals biphasic growth and abortive disassembly.

The synaptonemal complex (SC) is a dynamic structure formed between chromosomes during meiosis which stabilizes and supports many essential meiotic processes such as pairing and recombination. In budding yeast, Zip1 is a functionally conserved element of the SC that is important for synapsis. Here, we directly measure the kinetics of Zip1-GFP assembly and disassembly in live cells of the yeast S. cerevisiae. The imaging of SC assembly in yeast is challenging due to the large number of chromosomes packed into a small nucleus. We employ a zip3Δ mutant in which only a few chromosomes undergo synapsis at any given time, initiating from a single site on each chromosome, thus allowing the assembly and disassembly kinetics of single SCs to be accurately monitored in living cells. SC assembly occurs with both monophasic and biphasic kinetics, in contrast to the strictly monophasic assembly seen in C. elegans. In wild-type cells, once maximal synapsis is achieved, programmed final disassembly rapidly follows, as Zip1 protein is actively degraded. In zip3Δ, this period is extended and final disassembly is prolonged. Besides final disassembly, we found novel disassembly events involving mostly short SCs that disappeared in advance of programmed final disassembly, which we termed "abortive disassembly." Abortive disassembly is distinct from final disassembly in that it occurs when Zip1 protein levels are still high, and exhibits a much slower rate of disassembly, suggesting a different mechanism for removal in the two types of disassembly. We speculate that abortive disassembly events represent defective or stalled SCs, possibly representing SC formation between non-homologs, that is then targeted for dissolution. These results reveal novel aspects of SC assembly and disassembly, potentially providing evidence of additional regulatory pathways controlling not just the assembly, but also the disassembly, of this complex cellular structure.

Alcohol and cannabis co-use in a national sample of U.S. adults ages 30-80.

INTRODUCTION: Growing cannabis legalization has coincided with an increased focus on use of both alcohol and cannabis (AC co-use) among younger people; however, little is known about AC co-use among adults over age 30. This study examines the prevalence of different types of AC co-use among adults, as well as compares AC co-users and alcohol-only users on individual, social network, and neighborhood characteristics. METHODS: Data come from three annual surveys of a nationally representative sample of 1,770 U.S. adults, initially between the ages of 30-80, conducted between 2019 and 2021. The baseline sample is 52.8 years old on average, 51.8 % female, and 60.1 % non-Hispanic White. RESULTS: Past month co-use at baseline was reported by 8.4% of adults, and mostly consisted of simultaneous use, with less than 5% of the sample initiating co-use over the two-year follow-up period. Multivariable models indicate AC co-use was cross-sectionally associated with respondents being male, younger, Hispanic (vs White), and having more alcohol use and related problems, and with their social network composition (e.g., having more drinking buddies and cannabis users in the network). However, co-use status was not associated with mental health, physical ailments, or neighborhood quality. Longitudinal analyses indicated that AC co-use at baseline predicted more alcohol use one year later and alcohol related problems two years later among men only. CONCLUSIONS: AC co-use among adults over age 30 deserves further attention given its prevalence and associations with heavier drinking and related problems. Network-focused interventions may be a promising approach for reducing AC co-use.

Driving unidirectional molecular rotary motors with visible light by intra- and intermolecular energy transfer from palladium porphyrin.

Driving molecular rotary motors using visible light (530-550 nm) instead of UV light was achieved using palladium tetraphenylporphyrin as a triplet sensitizer. Visible light driven rotation was confirmed by UV/vis absorption, circular dichroism and (1)H NMR spectroscopy and the rotation was confirmed to be unidirectional and with similar photostationary states, despite proceeding via a triplet instead of a singlet excited state of the molecular motor. Energy transfer proceeds in both inter- and intramolecular fashion from the triplet state of the porphyrin to the motor. Stern Volmer plots show that the rate of intermolecular quenching of the porphyrin excited state by the molecular motor is diffusion-controlled.

Molecular machines: nanomotor rotates microscale objects.

Nanomachines of the future will require molecular-scale motors that can perform work and collectively induce controlled motion of much larger objects. We have designed a synthetic, light-driven molecular motor that is embedded in a liquid-crystal film and can rotate objects placed on the film that exceed the size of the motor molecule by a factor of 10,000. The changes in shape of the motor during the rotary steps cause a remarkable rotational reorganization of the liquid-crystal film and its surface relief, which ultimately causes the rotation of submillimetre-sized particles on the film.

Decline in Trust in the Centers for Disease Control and Prevention During the COVID-19 Pandemic.

Researchers present a subset of results from May and October 2020 surveys fielded through the RAND American Life Panel to assess changes in levels of trust in the Centers for Disease Control and Prevention during the coronavirus disease 2019 pandemic. Non-Hispanic White and Hispanic respondents reported significant declines in trust, while the changes were not statistically significant for non-Hispanic Black respondents or respondents of other races.

Trajectories of alcohol use and problems during the COVID-19 pandemic: The role of social stressors and drinking motives for men and women.

INTRODUCTION: Increased alcohol use coinciding with onset of the COVID-19 pandemic, particularly among women, has been documented among U.S. adults. This study examines trajectories of alcohol use and alcohol problems over a 9-month period during the pandemic, the extent to which these trajectories are predicted by social stress and drinking motives, and whether results differ for women and men. METHODS: Data come from three online surveys of a nationally representative sample of U.S. adults ages 30-80 conducted in May-July 2020, October-November 2020, and March 2021. The analytic sample consists of N = 1118 who initially reported any past year alcohol use. The early-COVID survey assessed demographics, social stressors, and drinking motives. All three surveys assessed average drinks per day in past month and drinking-related problems. RESULTS: Alcohol use declined for men, but remained stable for women. Alcohol problems increased for both sexes, especially for men. Level of alcohol use was associated with loneliness and social demands for men, and drinking motives for both sexes, with changes in use related to loneliness and social demands for men. Level of alcohol problems was associated with loneliness for women and drinking motives for both sexes, with changes in problems related to drinking motives for women. Interactions of social stress with drinking motives were not found. CONCLUSIONS: Sex differences in alcohol use and alcohol problems during the pandemic-as well as their associations with indicators of social stress and drinking motives-highlight the importance of tailoring prevention and treatment efforts for men and women.

Unidirectional molecular motor on a gold surface.

Molecules capable of mimicking the function of a wide range of mechanical devices have been fabricated, with motors that can induce mechanical movement attracting particular attention. Such molecular motors convert light or chemical energy into directional rotary or linear motion, and are usually prepared and operated in solution. But if they are to be used as nanomachines that can do useful work, it seems essential to construct systems that can function on a surface, like a recently reported linear artificial muscle. Surface-mounted rotors have been realized and limited directionality in their motion predicted. Here we demonstrate that a light-driven molecular motor capable of repetitive unidirectional rotation can be mounted on the surface of gold nanoparticles. The motor design uses a chiral helical alkene with an upper half that serves as a propeller and is connected through a carbon-carbon double bond (the rotation axis) to a lower half that serves as a stator. The stator carries two thiol-functionalized 'legs', which then bind the entire motor molecule to a gold surface. NMR spectroscopy reveals that two photo-induced cis-trans isomerizations of the central double bond, each followed by a thermal helix inversion to prevent reverse rotation, induce a full and unidirectional 360 degrees rotation of the propeller with respect to the surface-mounted lower half of the system.

Associations of social capital with binge drinking in a national sample of adults: The importance of neighborhoods and networks.

BACKGROUND: While considerable research on adult binge drinking has focused on social influences, the potential role of social capital has been largely overlooked. This study examines the role of social capital, assessed in terms of both neighborhood and social network characteristics, in understanding adult binge drinking. METHODS: Adults ages 30-80 were randomly drawn from the RAND American Life Panel and completed an online survey (analytic sample n = 1383). The main predictor variables were neighborhood cohesion, neighborhood order, and social network density. Associations of social capital with past month binge drinking (any, number of days) were examined, controlling for demographic characteristics. RESULTS: Zero-inflated negative binominal regression analysis indicated that any binge drinking was more likely among adults who lived in highly ordered neighborhoods and who had denser social networks but was negatively associated with neighborhood cohesion. However, binge drinking was more frequent among those who lived in neighborhoods lacking order and who had sparser social networks, but had no association with neighborhood cohesion. Age was not found to moderate associations of social capital with binge drinking. CONCLUSIONS: Given that the associations of social capital with adult binge drinking behavior appear to differ by level of influence and type of drinking behavior, there is a need to gain a more nuanced understanding of these complex associations, including the mechanisms through which they operate.

Rotary molecular motors: a large increase in speed through a small change in design.

Reducing the steric interaction between the upper-half and the lower-half of a light-driven rotary molecular motor by decreasing the size of the aromatic moiety in the upper-half from a naphthalene to a benzothiophene results in an almost 3500 times faster rotation.

An enantioselective synthetic route toward second-generation light-driven rotary molecular motors.

Controlling the unidirectional rotary process of second-generation molecular motors demands access to these motors in their enantiomerically pure form. In this paper, we describe an enantioselective route to three new second-generation light-driven molecular motors. Their synthesis starts with the preparation of an optically active alpha-methoxy-substituted upper-half ketone involving an enzymatic resolution. The subsequent conversion of this ketone to the corresponding hydrazone by treatment with hydrazine led to full racemization. However, conversion to a TBDMS-protected hydrazone by treatment with bis-TBDMS hydrazine, prepared according to a new procedure, proceeds with nearly full retention of the stereochemical integrity. Oxidation of the TBDMS-protected hydrazone and subsequent coupling to a lower-half thioketone followed by recrystallization provided the molecular motors with >99% ee. As these are the first molecular motors that have a methoxy substituent at the stereogenic center, the photochemical and thermal isomerization steps involved in the rotary cycle of one of these new molecules were studied in detail with various spectroscopic techniques.

Socioeconomic status and well-being during COVID-19: A resource-based examination.

The authors assess levels and within-person changes in psychological well-being (i.e., depressive symptoms and life satisfaction) from before to during the COVID-19 pandemic for individuals in the United States, in general and by socioeconomic status (SES). The data is from 2 surveys of 1,143 adults from RAND Corporation's nationally representative American Life Panel, the first administered between April-June, 2019 and the second during the initial peak of the pandemic in the United States in April, 2020. Depressive symptoms during the pandemic were higher than population norms before the pandemic. Depressive symptoms increased from before to during COVID-19 and life satisfaction decreased. Individuals with higher education experienced a greater increase in depressive symptoms and a greater decrease in life satisfaction from before to during COVID-19 in comparison to those with lower education. Supplemental analysis illustrates that income had a curvilinear relationship with changes in well-being, such that individuals at the highest levels of income experienced a greater decrease in life satisfaction from before to during COVID-19 than individuals with lower levels of income. We draw on conservation of resources theory and the theory of fundamental social causes to examine four key mechanisms (perceived financial resources, perceived control, interpersonal resources, and COVID-19-related knowledge/news consumption) underlying the relationship between SES and well-being during COVID-19. These resources explained changes in well-being for the sample as a whole but did not provide insight into why individuals of higher education experienced a greater decline in well-being from before to during COVID-19. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Low-contrast bandgaps of a planar parabolic spiral lattice.

We show that a planar aperiodic lattice, mimicking the appearance of a sunflower, supports photonic bandgaps for weak dielectric contrast. The pattern's high orientational order and spatially uniform modal pitch yields an isotropic Fourier space. A 2D structure of cylinders (=2) in air possesses a wide 21% TM bandgap, versus 5.6% for a sixfold lattice or 14% for a 12-fold fractal tiling. The isotropic gap frequencies imply flat bands, and thus application in nonlinear optics and low threshold lasers, where a reduced group velocity in all directions may be desired.

A trimer of ultrafast nanomotors: synthesis, photochemistry and self-assembly on graphite.

Lightning quick! A new ultrafast light-driven molecular motor was developed, which was readily incorporated into a larger trimeric system. The trimer of these motors was studied with STM and at the interface of highly oriented pyrolytic graphite and 1-phenyloctane the molecules form stable arrays in which the chirality of the trimer is expressed on both the molecular and the supramolecular level (see figure).