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Information and communications technology (ICT) companies like Amazon, Apple, Facebook, Google, and Twitter are vitally important to billions of users around the world, not only in their day-to-day personal and professional lives, but also in their ability to shape social and political reality. Yet there is a pervasive lack of clarity around the policies and practices that govern user engagement on these platforms and sites, and the values that undergird them. This information is of great importance to policy researchers and civil society advocates, particularly in the wake of numerous recent events that have put the relative power and opacity of ICT companies in the spotlight. Access to information about them is often incredibly difficult to obtain, when it is available at all. These difficulties are faced by many categories of people interested in researching ICT companies, from academics to journalists, and from civil society advocates to policy researchers. In this white paper, we outline some of the challenges we have identified as being particularly acute for policy researchers, as well as strategies for working through (and around) those issues.

The story of a rogue Canadian garbage barge attempting to offload illegal garbage in the Philippines opens this article on techno-trash, in order to underline both the relationships between countries of the Global North with countries of the Global South in matters of waste, as well as to reframe discussions of techno-trash as fundamentally tied to material things. The definition of techno-trash is then expanded, to cover digital detritus created through an entirely digital set of practices I term “Commercial Content Moderation.” The attempt to offload mounds of e-waste and the similar ways in which a great deal of physical trash circulates around the globe are then directly connected to the kind of disposal that CCM workers do, increasingly undertaken in sites like the Philippines, the Business Process Outsourcing (or BPO) capital of world. Such e-waste arrives in the archipelago for dismantling, repurpose and storage, alongside outsourced CCM, work with many of the objects now deemed “waste” once crucial to the production of the very material for which CCM workers now screen and remove.

Singlet fission (SF) materials used in light-harvesting devices must not only efficiently produce spin-triplet excitons but also transport them to an energy acceptor. N , N '-Bis(2-phenylethyl)-3,4,9,10-perylenedicarboximide (EP-PDI) is a promising SF chromophore due to its photostability, large extinction coefficient, and high triplet yield, but the energy transport mechanisms in EP-PDI solids are minimally understood. Herein, we use transient absorption microscopy to directly characterize exciton transport in EP-PDI crystals. We find evidence for singlet-mediated transport in which pairs of triplet excitons undergo triplet fusion (TF), producing spin-singlet excitons that rapidly diffuse. This interchange of singlet and triplet excitons shuttles triplets as far as 205 nm within the first 500 ps after photoexcitation. This enhanced transport comes at a cost, however, as it necessitates favoring triplet recombination and thus requires fine-tuning of SF dynamics to balance triplet yields with triplet transport lengths. Through numerical modeling, we predict tuning the ratio of SF and TF rate constants, k SF / k TF , to between 1.9 and 3.8 allows for an optimized triplet transport length (425-563 nm) with minimal loss (7-10%) in triplet yield. Interestingly, by adjusting the size of EP-PDI crystals, we find that we can subtly tune their crystal structure and thereby alter their SF and TF rates. By slowing SF within small EP-PDI crystals, we are able to boost their triplet transport length by ∼20%. Although counterintuitive, our work suggests slowing SF by introducing moderate structural distortions can be preferential when optimizing triplet exciton transport, provided singlet exciton transport is not significantly hindered.

Background: Sexual violence (SV) increases HIV susceptibility in a sustained manner. This study evaluated genital cytokines and colposcopy findings in women reporting both recent and more remote SV.Methods: A cross-sectional study of HIV-1 negative Kenyan women who engage in sex work (WESW) was performed. Cervicovaginal fluid was collected by menstrual cup and cytokines (IFNγ, TNFα, IL-1β, IL-6, IL-10, MIP-1α, MIP-1β and CXCL10) measured using chemiluminescence. Cervical injury was assessed by colposcopy. Associations between recent (≤30 days prior), more remote (>30 days prior) and no (reference category) SV exposure and cytokine concentrations were evaluated using linear regression., Results: Among 282 participants, 25 (8.9%) reported recent SV and 123 (43.6%) reported more remote SV. Only two cytokines (IL-10 and CXCL10) were associated with the 3-category SV variable in bivariable modeling at the pre-specified cut-off (p < 0.2) and carried forward. In multivariable analyses, more remote SV (β = 0.72, 95% CI 0.06, 1.38; p = 0.03), but not recent SV (β = 0.20, 95%CI -0.99, 1.39; p = 0.74) was associated with cervicovaginal IL-10 compared to no SV. Recent (β = 0.36, 95% CI -0.94, 1.67; p = 0.58) and more remote (β = 0.51, 95% CI -0.21, 1.24; p = 0.16) SV were not associated with CXCL10 compared to no SV. Cervical epithelial friability (χ2 = 1.3, p = 0.51), erythema (χ2 = 2.9, p = 0.24), vascular disruption (χ2 = 1.4; p = 0.50), epithelial disruption (χ2 = 2.6, p = 0.27), or any colposcopy finding (χ2 = 1.2, p = 0.54) were not associated with SV category by chi-square test., Conclusions: The mechanism linking SV to sustained increases in HIV susceptibility may not be related to persistent genital inflammation or injury., Competing Interests: Conflicts of interest: RSM receives research funding, paid to the University of Washington, from Hologic Corporation. JO is on the scientific advisory board of Aerium Therapeutics. For the remaining authors, no conflicts of interest were declared., (Copyright © 2024 American Sexually Transmitted Diseases Association. All rights reserved.)

We evaluated correlates of adherence to PrEP, including daily oral tenofovir disoproxil fumarate in combination emtricitabine (oral FTC/TDF) and the monthly dapivirine ring (ring)among adolescent girls and young women (AGYW) in the MTN-034/REACH study. We enrolled 247 AGYW aged 16-21 years in South Africa, Uganda and Zimbabwe (ClinicalTrials.gov: NCT03074786). Participants were randomized to the order of oral FTC/TDF or ring use for 6 months each in a crossover period, followed by a 6-month choice period. We assessed potential adherence correlates-individual, interpersonal, community, study, and product-related factors-quarterly via self-report. We measured biomarkers of adherence monthly; high adherence was defined as > 4 mg dapivirine released from returned rings or intracellular tenofovir diphosphate levels ≥ 700 fmol/punch from dried blood spots (DBS). We tested associations between correlates and objective measures of high adherence using generalized estimating equations. High adherence to oral FTC/TDF was significantly associated with having an older primary partner (p = 0.04), not having exchanged sex in the past 3 months (p = 0.02), and rating oral FTC/TDF as highly acceptable (p = 0.003). High ring adherence was significantly associated with unstable housing (p = 0.01), disclosing ring use to a male family member (p = 0.01), and noting a social benefit from study participation (p = 0.03). All associations were moderate, corresponding to about 6%-10% difference in the proportion with high adherence. In our multinational study, correlates of adherence among African AGYW differed for oral FTC/TDF and the ring, highlighting the benefit of offering multiple PrEP options., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

With new pre-exposure prophylaxis (PrEP) modalities for HIV prevention becoming available, understanding how adolescent girls and young women (AGYW) navigate through PrEP options is essential, including factors underlying their choice. Through 16 focus group discussions (FGDs) and 52 in-depth interviews (IDIs) from REACH, an open-label crossover study in which AGYW were allocated 1:1 (between 06 February 2019 and 18 March 2020) to receive oral PrEP for six months and the dapivirine ring for six months, in a randomized sequence, followed by a 6-month period where either product (or neither) could be chosen, we explored decision-making process and product choice, using a mixed inductive-deductive analytical approach. Key themes included the desire to remain HIV-negative and weighing product attributes through experiential learning. Product triability appeared important in informing product choice as individual circumstances changed or assuaging side effects with a given product. Approved biomedical prevention innovations may also benefit from hands-on experience to help with adoption and use during real-world implementation. Furthermore, support from trusted providers will remain critical as AGYW contemplate navigating through PrEP options and choice., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Atujuna et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The Tu'Washindi intervention addressed intimate partner violence (IPV) and relationship dynamics to increase PrEP use among adolescent girls and young women (AGYW) in Siaya County, Kenya. We evaluated feasibility and acceptability in a cluster-randomized trial in six DREAMS Safe Spaces. The multilevel intervention, delivered over 6 months, included three components delivered by DREAMS staff with support from the study team: an 8-session structured support club; community sensitization of male partners; and a couples PrEP education and health fair ("Buddy Day"). Feasibility and acceptability assessments included implementation process measures, questionnaires, and focus group discussions with AGYWs and post-intervention questionnaires with intervention providers. The study included 103 AGYWs aged 17 to 24 (N = 49 intervention), with 97% retention. Median age was 22, 54% were married, and 84% were mothers. At enrollment, 45% used PrEP and 61% reported lifetime IPV. All intervention participants attended at least one support club session (mean = 5.2 of 8) and 90% attended Buddy Day. At 6 months, most participants perceived Tu'Washindi to be effective: all agreed (with 54% reporting "strongly agree") that the intervention improved partner communication and 60% agreed they were better able to gain partner support for their PrEP use. Providers believed the intervention resonated with community values. Tu'Washindi was highly acceptable and feasible and it was perceived by AGYW participants and providers as being effective in improving partner relationships and supporting PrEP use., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The Elateridae, or click beetles are abundant and diverse in most terrestrial ecosystems in North America, acting as plant pests and filling many other ecological roles. The 112 genera of Elateridae Leach, 1815, or click beetles, known from Canada and USA are included in a first comprehensive digital interactive key to adults. A link to an online peer-reviewed LUCID key to elaterid genera and downloadable LUCID files are provided. Diagnostic morphological summaries using information from the 61 characters and 158 character states of the matrix key are presented for all genera. A table summarizes current understanding of habitat use by all elaterid genera in Canada and USA from literature, collections, citizen science, and our own observations. Diversity of elaterid genera was high throughout warm and cool temperate regions, especially in mountainous areas and mesic woodlands. Larvae of most genera were associated with soil, litter and decaying wood., Competing Interests: The authors have declared that no competing interests exist.

Singlet fission produces a pair of low-energy spin-triplet excitons from a single high-energy spin-singlet exciton. While this process offers the potential to enhance the efficiency of silicon solar cells by ∼30%, meeting this goal requires overlayer materials that can efficiently transport triplet excitons to an underlying silicon substrate. Herein, we demonstrate that the chemical functionalization of silicon surfaces controls the structure of vapor-deposited thin films of perylenediimide (PDI) dyes, which are prototypical singlet fission materials. Using a combination of atomic force microscopy (AFM) and grazing-incidence wide-angle X-ray scattering (GIWAXS), we find terminating Si(111) with either a thin, polar oxide layer (SiO x ) or with hydrophobic methyl groups (Si-CH 3 ) alters the structures of the resulting PDI films. While PDI films grown on SiO x are comprised of small crystalline grains that largely adopt an "edge-on" orientation with respect to the silicon surface, films grown on Si-CH 3 contain large grains that prefer to align in a "face-on" manner with respect to the substrate. This "face-on" orientation is expected to enhance exciton transport to silicon. Interestingly, we find that the preferred mode of growth for different PDIs correlates with the space group associated with bulk crystals of these compounds. While PDIs that inhabit a monoclinic ( P 2 1 / c ) space group nucleate films by forming tall and sparse crystalline columns, PDIs that inhabit triclinic ( P 1̅) space groups afford films comprised of uniform, lamellar PDI domains. The results highlight that silicon surface functionalization profoundly impacts PDI thin film growth, and rational selection of a hydrophobic surface that promotes "face-on" adsorption may improve energy transfer to silicon.

Introduction: Stigma is a well-known barrier to HIV testing and treatment and is an emerging barrier to pre-exposure prophylaxis (PrEP) use. To guide future research, measurement and interventions, we developed a conceptual framework for PrEP stigma among adolescent girls and young women (AGYW) in sub-Saharan Africa, a priority population for PrEP., Methods: A literature review, expert consultations and focus group discussions (FGDs) were conducted to adapt the Health Stigma and Discrimination Framework, describing the stigmatization process nested within the socio-ecological framework. We reviewed all articles on PrEP stigma and on HIV, contraceptive or sexuality stigma among AGYW from 2009 to 2019. Expert consultations were conducted with 10 stigma or PrEP researchers and two Kenyan youth advisory boards to revise the framework. Finally, FGDs were conducted with AGYW PrEP users (4 FGDs; n = 20) and key influencers (14 FGDs; n = 72) in Kenya with the help of a Youth Research Team who aided in FGD conduct and results interpretation. Results from each phase were reviewed and the framework was updated to incorporate new and divergent findings. This was validated against an updated literature search from 2020 to 2023., Results: The conceptual framework identifies potential drivers, facilitators and manifestations of PrEP stigma, its outcomes and health impacts, and relevant intersecting stigmas. The main findings include: (1) PrEP stigma is driven by HIV, gender and sexuality stigmas, and low PrEP community awareness. (2) Stigma is facilitated by factors at multiple levels: policy (e.g. targeting of PrEP to high-risk populations), health systems (e.g. youth-friendly service availability), community (e.g. social capital) and individual (e.g. empowerment). (3) Similar to other stigmas, manifestations include labelling, violence and shame. (4) PrEP stigma results in decreased access to and acceptability of PrEP, limited social support and community resistance, which can impact mental health and decrease PrEP uptake and adherence. (5) Stigma may engender resilience by motivating AGYW to think of PrEP as an exercise in personal agency., Conclusions: Our PrEP stigma conceptual framework highlights potential intervention targets at multiple levels in the stigmatization process. Its adoption would enable researchers to develop standardized measures and compare stigma across timepoints and populations as well as design and evaluate interventions., (© 2024 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

The rapid photochemical conversion of materials from liquid to solid (i.e., curing) has enabled the fabrication of modern plastics used in microelectronics, dentistry, and medicine. However, industrialized photocurables remain restricted to unimolecular bond homolysis reactions (Type I photoinitiations) that are driven by high-energy UV light. This narrow mechanistic scope both challenges the production of high-resolution objects and restricts the materials that can be produced using emergent manufacturing technologies (e.g., 3D printing). Herein we develop a photosystem based on triplet-triplet annihilation upconversion (TTA-UC) that efficiently drives a Type I photocuring process using green light at low power density (<10 mW/cm 2 ) and in the presence of ambient oxygen. This system also exhibits a superlinear dependence of its cure depth on the light exposure intensity, which enhances spatial resolution. This enables for the first-time integration of TTA-UC in an inexpensive, rapid, and high-resolution manufacturing process, digital light processing (DLP) 3D printing. Moreover, relative to traditional Type I and Type II (photoredox) strategies, the present TTA-UC photoinitiation method results in improved cure depth confinement and resin shelf stability. This report provides a user-friendly avenue to utilize TTA-UC in ambient photochemical processes and paves the way toward fabrication of next-generation plastics with improved geometric precision and functionality., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Materials that undergo singlet fission are of interest for their use in light-harvesting, photocatalysis, and quantum information science, but their ability to undergo fission can be sensitive to local variations in molecular packing. Herein we employ transient absorption microscopy, molecular dynamics simulations, and electronic structure calculations to interrogate how structures found at the edges of orthorhombic rubrene crystals impact singlet fission. Within a micrometer-scale spatial region at the edges of rubrene crystals, we find that the rate of singlet fission increases nearly 4-fold. This observation is consistent with formation of a region at crystal edges with reduced order that accelerates singlet fission by disrupting the symmetry found in rubrene's orthorhombic crystal structure. Our work demonstrates that structural distortions of singlet fission materials can be used to control fission in time and in space, potentially offering a means of controlling this process in light harvesting and quantum information applications.

Effective use of oral pre-exposure prophylaxis (PrEP) has been low among adolescent girls and young women (AGYW) in Eastern and Southern Africa, partly due to stigma and opposition from key influencers. Understanding AGYW's experiences of disclosure of different PrEP modalities to key influencers may inform strategies to motivate uptake and adherence. We analyzed qualitative in-depth interviews and focus group discussions data from 119 participants in the MTN-034/REACH (Reversing the Epidemic in Africa with Choices in HIV Prevention) study of oral PrEP and the dapivirine vaginal ring (ring) to explore AGYW's disclosure experiences. We found that AGYW disclosure experiences varied across influencers and product type. The ring was disclosed less often to most influencers, except partners, because it was discreet. Oral PrEP was disclosed more often, because pills were more common and to avoid HIV stigma given that oral PrEP resembled HIV treatment. Ultimately, disclosure typically led most key influencers to support product use through reminders and encouragement. While disclosure yielded positive support from influencers, further community awareness of both PrEP products is essential to reduce potential opposition and perceived stigma.Clinical Trial Number: NCT03593655., (© 2023. The Author(s).)

Introduction: Oral pre-exposure prophylaxis (PrEP) has the potential to reduce HIV acquisition among adolescent girls and young women (AGYW) in sub-Saharan Africa, a priority population for epidemic control. However, intimate partner violence (IPV) and low relationship power can create significant challenges to PrEP use. The Tu'Washindi intervention aimed to increase PrEP use by addressing relationship- and violence-related barriers among AGYW enrolled in the DREAMS Initiative in Siaya County, Kenya., Methods: Our multi-level, community-based intervention was piloted in a cluster-randomized controlled trial conducted at six DREAMS sites from April to December 2019 (NCT03938818). Three intervention components were delivered over 6 months: an eight-session empowerment-based support club, community sensitization targeted towards male partners and a couples' PrEP education event. Participants were ages 17-24, HIV negative and either eligible for, or already taking, PrEP. Over 6 months of follow-up, we assessed IPV (months 3 and 6) and PrEP uptake and continuation (month 6) through interviewer-administered questionnaires; PrEP adherence was assessed with Wisepill electronic monitoring devices. These outcomes were compared using adjusted Poisson and negative binomial regression models., Results: We enrolled 103 AGYW with median age of 22 years (IQR 20-23); one-third were currently taking PrEP and 45% reported IPV in the past 3 months. Retention was 97% at month 6. Compared to the control arm, intervention arm participants were more likely to initiate PrEP, if not already using it at enrolment (52% vs. 24%, aRR 2.28, 95% CI 1.19-4.38, p = 0.01), and those taking PrEP had more days with device openings (25% of days vs. 13%, aRR 1.94, 95% CI 1.16-3.25, p = 0.01). Twenty percent of participants reported IPV during follow-up. There were trends towards fewer IPV events (aIRR 0.66, 95% CI 0.27-1.62, p = 0.37) and fewer events resulting in injury (aIRR 0.21, 95% CI 0.04-1.02, p = 0.05) in the intervention versus control arm., Conclusions: Tu'Washindi shows promise in promoting PrEP uptake and adherence among AGYW without concomitant increases in IPV; however, adherence was still suboptimal. Further research is needed to determine whether these gains translate to increases in the proportion of AGYW with protective levels of PrEP adherence and to evaluate the potential for the intervention to reduce IPV risk., (© 2023 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

We are far from knowing all species living on the planet. Understanding biodiversity is demanding and requires time and expertise. Most groups are understudied given problems of identifying and delimiting species. DNA barcoding emerged to overcome some of the difficulties in identifying species. Its limitations derive from incomplete taxonomic knowledge and the lack of comprehensive DNA barcode libraries for so many taxonomic groups. Here, we evaluate how useful barcoding is for identifying arthropods from highly diverse leaf litter communities in the southern Appalachian Mountains (USA). We used 3 reference databases and several automated classification methods on a data set including several arthropod groups. Acari, Araneae, Collembola, Coleoptera, Diptera, and Hymenoptera were well represented, showing different performances across methods and databases. Spiders performed the best, with correct identification rates to species and genus levels of ~50% across databases. Springtails performed poorly, no barcodes were identified to species or genus. Other groups showed poor to mediocre performance, from around 3% (mites) to 20% (beetles) correctly identified barcodes to species, but also with some false identifications. In general, BOLD-based identification offered the best identification results but, in all cases except spiders, performance is poor, with less than a fifth of specimens correctly identified to genus or species. Our results indicate that the soil arthropod fauna is still insufficiently documented, with many species unrepresented in DNA barcode libraries. More effort toward integrative taxonomic characterization is needed to complete our reference libraries before we can rely on DNA barcoding as a universally applicable identification method., (© The Author(s) 2023. Published by Oxford University Press on behalf of Editorial Office, Current Zoology.)

Introduction: Effective use of oral HIV pre-exposure prophylaxis (PrEP) has been lower among African adolescent girls and young women (AGYW) than among older women, young men who have sex with men, and serodiscordant heterosexual couples in the region. Efforts to build PrEP support have centered around peers and male partners, but the family may also play an important role. This qualitative study aimed to describe family influence on PrEP use among AGYW in in three African cities., Methods: POWER (Prevention Options for Women Evaluation Research) was a PrEP demonstration project among 2550 AGYW (16-25 years old) in Johannesburg and Cape Town, South Africa and Kisumu, Kenya conducted from 2017 to 2020. In-depth interviews and focus group discussions were conducted with 136 AGYW participants to explore their PrEP views and experiences, including awareness and interest in PrEP; barriers and facilitators to uptake and use; the influence of family, peers, intimate partners, and community; and the key types of support for their PrEP use. Transcripts were coded and analysed thematically., Results: The decision to initiate PrEP was associated with fear and anxiety linked to anticipated stigma from family members, and with family's lived HIV experience. Family disclosure, especially to mothers, was important to participants, as most lived with their families and considered it essential for them to obtain their mother's approval to use PrEP. Most family members, particularly mothers, provided instrumental, emotional, informational and appraisal support to participants using PrEP, including reminders, encouragement, and problem-solving. Participants reported that family members with insufficient information about PrEP safety and efficacy and who voiced concerns were a substantial barrier to their use. However, they often became supportive after receiving more PrEP information., Conclusion: Families, particularly mothers, can play an important role in supporting PrEP use. PrEP programmes should leverage family support to help with PrEP persistence by providing basic information to families about PrEP safety and efficacy. AGYW using PrEP should be encouraged to selectively disclose PrEP use to build support and counseled on how to disclose and address family concerns., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Ndimande-Khoza et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Effective use of pre-exposure prophylaxis (PrEP) has been low among adolescent girls and young women (AGYW) in sub-Saharan Africa. The MTN-034/REACH trial offered AGYW a menu of adherence support strategies and achieved high adherence to both daily oral PrEP and the monthly dapivirine vaginal ring. Understanding how these strategies promoted product use could inform the design of adherence support systems in programmatic settings., Methods: REACH was a randomized crossover trial evaluating the safety of and adherence to the ring and oral PrEP among 247 HIV-negative AGYW (ages 16-21) in South Africa, Uganda and Zimbabwe from January 2019 to September 2021 (NCT03593655). Adherence support included monthly counselling sessions with drug-level feedback (DLF) plus optional daily short message service (SMS) reminders, weekly phone or SMS check-ins, peer support clubs, "peer buddies" and additional counselling. Counsellors documented adherence support choices and counselling content on standardized forms. Through focus groups, serial in-depth interviews (IDIs) and single IDIs (n = 119 total), we explored participants' experiences with adherence support and how it encouraged product use., Results: Participants received counselling at nearly all visits. DLF was provided at 54.3% of sessions and, across sites, 49%-68% received results showing high adherence for oral PrEP, and 73%-89% for the ring. The most popular support strategies were in-person clubs and weekly calls, followed by online clubs, additional counselling and SMS. Preferences differed across sites but were similar for both products. Qualitative results demonstrated that the REACH strategies supported adherence by providing information about HIV and PrEP, continually motivating participants, and supporting the development of behavioural skills and self-efficacy, aligning with the Information, Motivation, and Behavioural Skills (IMB) model. Effectiveness was supported by three foundational pillars: strong interpersonal relationships with counsellors; ongoing, easily accessible support and resources; and establishing trust in the counsellors and study products through counsellor relationships, peer-to-peer exchange and DLF., Conclusions: Implementation programmes could support effective PrEP use by offering a small menu of counsellor- and peer-based support options that are youth-friendly and developmentally appropriate. The same menu options can support both ring and oral PrEP users, though content should be tailored to the individual products., (© 2023 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of International AIDS Society.)

Introduction: In response to the diverse roles and strong influence that male partners may have in women's decisions and ability to use HIV prevention products, we previously developed the counselor-administered Healthy Relationship Assessment Tool (HEART). This tool helps counselors tailor pre-exposure prophylaxis (PrEP) adherence support counseling to women's relationship dynamics with their sexual partners, suggesting modules for counselors to deliver. In this study, we examined the extent to which counselors used the HEART to guide the delivery of intervention modules and whether changes in subsequent HEART scores reflected the counseling module(s) received., Methods: We conducted this study during a randomized controlled trial of the Community Health clinic model for Agency in Relationships and Safer Microbicide Adherence (CHARISMA) counseling intervention in Johannesburg, South Africa. Trained lay counselors administered the HEART to intervention group participants at enrollment (n=203) and at 3- and 6-month follow-up visits between October 2018 and April 2021. The HEART auto-calculated participants' response scores to recommend relevant counseling modules. We compared the mean scores for the 5 HEART scales across groups receiving different counseling modules. We also assessed changes in scale scores over time by the counseling module received., Results: Although counselors could override HEART counseling module recommendations based on additional knowledge of participants' cases, they consistently agreed with the HEART recommendations. The HEART also triggered the sorting of women into counseling modules that they were positioned to successfully leverage. Additionally, participants' HEART scores changed over time in predictable ways based on the type of counseling module received., Conclusion: Overall, the tool performed as predicted and was consistent with past validation efforts of the HEART, indicating that the HEART may provide an efficient means to tailor women's counseling to address relationship-related challenges to PrEP adherence., (© Zissette et al.)

Background: Intimate partner violence (IPV) and other relationship-based challenges have been demonstrated to reduce women's ability to use pre-exposure prophylaxis (PrEP) effectively for HIV prevention. The Community Health Clinical Model for Agency in Relationships and Safer Microbicide Adherence (CHARISMA) intervention was designed to mitigate these challenges and increase South African women's agency to use PrEP. The CHARISMA randomized controlled trial did not identify statistically significant differences in PrEP adherence or relationship dynamics between the intervention and control arms. As such, the aim of this explanatory qualitative sub-study was to understand women's experiences with the CHARISMA trial and explore reasons for the null results., Methods: Twelve CHARISMA trial participants were purposively selected to participate in serial in-depth interviews, which took place at the trial end and 3 months later. Participants represented individuals who had received each of the three counselling modules, 1) healthy communication counselling, 2) PrEP disclosure counselling, or 3) IPV counselling, as well as those in the control arm who received IPV standard-of-care counselling., Results: A thematic case analysis revealed numerous positive relationship outcomes among intervention participants, including identifying and ending unhealthy relationships, gaining a sense of personal empowerment, and enacting more positive behaviors and HIV risk reduction strategies in subsequent relationships. These positive shifts were occasionally described as contributing to decisions to discontinue PrEP use, which may partly explain the limited impact of the intervention on PrEP adherence., Conclusions: Future investigations of counselling interventions addressing relationship-based barriers to PrEP use should account for changing risk dynamics and need for PrEP., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Semiconducting nanocrystals passivated with organic ligands have emerged as a powerful platform for light harvesting, light-driven chemical reactions, and sensing. Due to their complexity and size, little structural information is available from experiments, making these systems challenging to model computationally. Here, we develop a machine-learned force field trained on DFT data and use it to investigate the surface chemistry of a PbS nanocrystal interfaced with acetate ligands. In doing so, we go beyond considering individual local minimum energy geometries and, importantly, circumvent a precarious issue associated with the assumption of a single assigned atomic partial charge for each element in a nanocrystal, independent of its structural position. We demonstrate that the carboxylate ligands passivate the metal-rich surfaces by adopting a very wide range of "tilted-bridge" and "bridge" geometries and investigate the corresponding ligand IR spectrum. This work illustrates the potential of machine-learned force fields to transform computational modeling of these materials.

Discreet, accessible interventions are urgently needed to mitigate the risk of intimate-partner violence (IPV) and other relationship barriers that women encounter to using HIV prevention methods such as pre-exposure prophylaxis (PrEP). We adapted a counsellor-administered intervention, CHARISMA, into a mobile-optimized website to enhance accessibility and reduce human resources required for HIV prevention and relationship counseling. Using human-centered design and participatory methods, CHARISMA was adapted through workshops with former CHARISMA in-person intervention participants (n = 14; ages 18-45) and web development 'sprints' combined with cognitive interviews (n = 24). 'CHARISMA mobile' was then beta-tested with 81 women naïve to the in-person intervention. In beta-testing, participants used a 'think aloud' process to provide feedback on ease of use and rated design, functionality, comprehension, confidentiality, safety, and usefulness on a scale of 1 to 5 via a survey. Data were conducted in four rounds, interspersed with rapid assessment according to go/no-go criteria, and website adaptations. The updated website was pilot tested for 'real-world' feasibility and acceptability among 159 women using their own smartphones at a location of their choice. Feedback was measured via surveys and website analytics. Workshops and cognitive interviews generated insights on technology use, contextual adaptations, and confidentiality, which were integrated into the beta version. The beta version met all 'go' criteria and was further adapted for pilot testing. In pilot testing, users found the website was useful (mean rating 4.54 out of 5), safe (4.5 out of 5), and had few concerns about confidentiality (1.75, representing low concern). On average, users rated the website more than 4 stars out of 5. Beta and pilot-testing suggested the smartphone-optimized website was well-accepted, relevant, engaging, feasible to administer, discreet and safe. Results contributed to a refined website, suitable for adaptations to other contexts and further evaluation where outcomes related to PrEP use and relationships should be assessed., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Hartmann et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Hybrid structures formed between organic molecules and inorganic quantum dots can accomplish unique photophysical transformations by taking advantage of their disparate properties. The electronic coupling between these materials is typically weak, leading photoexcited charge carriers to spatially localize to the dot or to a molecule at its surface. However, we show that by converting a chemical linker that covalently binds anthracene molecules to silicon quantum dots from a carbon-carbon single bond to a double bond, we access a strong coupling regime where excited carriers spatially delocalize across both anthracene and silicon. By pushing the system to delocalize, we design a photon upconversion system with a higher efficiency (17.2%) and lower threshold intensity (0.5 W cm -2 ) than that of a corresponding weakly coupled system. Our results show that strong coupling between molecules and nanostructures achieved through targeted linking chemistry provides a complementary route for tailoring properties in materials for light-driven applications., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Ultrafast optical microscopy, generally employed by incorporating ultrafast laser pulses into microscopes, can provide spatially resolved mechanistic insight into scientific problems ranging from hot carrier dynamics to biological imaging. This Review discusses the progress in different ultrafast microscopy techniques, with a focus on transient absorption and two-dimensional microscopy. We review the underlying principles of these techniques and discuss their respective advantages and applicability to different scientific questions. We also examine in detail how instrument parameters such as sensitivity, laser power, and temporal and spatial resolution must be addressed. Finally, we comment on future developments and emerging opportunities in the field of ultrafast microscopy., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Introduction: Adolescent girls and young women (AGYW) in sub-Saharan Africa are disproportionately affected by the HIV epidemic and face an array of challenges using proven behavioral and biomedical prevention methods. To address the urgent need for expanding prevention options, we evaluated the baseline preferences of HIV prevention methods among participants enrolled in the MTN-034/REACH crossover trial along with their stated product preference prior to product initiation., Methods: AGYW aged 16-21 years were enrolled at 4 study sites: Cape Town and Johannesburg, South Africa; Kampala, Uganda; and Harare, Zimbabwe and randomly assigned to the sequence of using oral PrEP and the dapivirine ring for 6 months each, followed by a choice period in which they could choose either product (or neither) for an additional six months. Eligible AGYW were HIV-negative, not pregnant and using effective contraception for at least two months prior to enrollment. Descriptive statistics were used to summarize demographic and behavioral data while multinomial analysis was used to determine predictors of stated product preference (ring or oral PrEP)., Results: Of the 247 AGYW enrolled in REACH, 34% were aged 16-17 and 89% had a primary partner.The median age of sexual debut was 16 years and 40% had ever been pregnant. At screening, 35% of participants were diagnosed with a sexually transmitted infection (STI), 39% had an AUDIT-C score associated with harmful drinking and 11% reported intimate partner violence in the past 6 months. Overall, 28% of participants, had CESD-10 scores suggestive of depressive symptoms (≥12) in the past week. At baseline, similar proportions stated a preference for the ring and oral PrEP (38.1% and 40.5% respectively), with 19% of participants stating they preferred both products equally. Only study site was significantly associated with product preference (P<0.05) with AGYW from Johannesburg having higher odds of preferring the ring and those from Kampala having higher odds of preferring both options equally., Conclusions: We successfully enrolled African AGYW with a clear unmet need for HIV prevention. The balanced preference between the two products suggests that multiple biomedical prevention options may be appealing to this age group and could address their prevention needs., Competing Interests: The authors have declared that no competing interests exist, (Copyright: © 2023 Ngure et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Intimate partner violence (IPV) has been associated with poorer mental health outcomes and increased human immunodeficiency virus (HIV) risk behaviors. We examine the relations between IPV, mental health symptomology (defined as psychological distress and alcohol misuse), and engagement in HIV risk behaviors among a sample of South African women who participated in a randomized controlled trial of CHARISMA, an intervention to increase women's agency to use oral pre-exposure prophylaxis (PrEP) safely and consistently as well as mitigate relationship challenges. We also examined the impact of trial participation on women's mental health, as well as the impact of psychological distress on the effectiveness of the CHARISMA intervention. Mental health symptomology and IPV exposure were prevalent and associated with some HIV risk and protective behaviors. Trial participation reduced psychological distress. There was no evidence for mental health symptomology impacting the effectiveness of the CHARISMA intervention., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Gendered power inequalities impact adolescent girls' and young women's (AGYW) sexual and reproductive health (SRH) outcomes. We investigated the influence of sexual relationship power on AGYW's SRH outcomes, including HIV pre-exposure prophylaxis (PrEP) persistence., Methods: The POWER study in Kisumu, Kenya, and Cape Town and Johannesburg, South Africa provided PrEP to 2,550 AGYW (aged 16-25). AGYW's perceived power in their primary sexual relationship was measured among the first 596 participants enrolled using the Sexual Relationship Power Scale's (SRPS) relationship control sub-scale. Multivariable regression was used to test for (1) key sociodemographic and relationship characteristics associated with relationship power; and (2) the association of relationship power with SRH outcomes including PrEP persistence., Results: In this cohort, the mean SRPS score was 2.56 (0.49), 542 (90.9%) initiated PrEP; 192 (35.4%) persisted with PrEP at 1 month of which 46 (24.0% of 192) persisted at 6 months. SRPS were significantly lower among AGYW who cohabited with their sex partner (-0.14, 95% CI: -0.24 to -0.04, p  = 0.01), or had ≥1 sex partner (-0.10, 95% CI: -0.19 to -0.00, p  = 0.05). AGYW with lower SRPS were more likely to not know their partner's HIV status (aOR 2.05, 95% CI: 1.27 to 3.33, p  < 0.01), but SRPS was not associated with PrEP persistence, STI infection, condom, or hormonal contraception use., Discussion: AGYW's reasons for initiating PrEP and reasons for continuously using PrEP may be different. While low relationship power was associated with perceived HIV vulnerability, AGYW's PrEP persistence may be influenced by more than relationship power., Competing Interests: ER, JB, CC, L-GB, SD-M reports personal fees from Gilead Science outside the submitted work. JB is employed by Gilead Sciences, Inc. JH has received consultation fees from Merck. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The reviewer AV declared a shared parent affiliation with the author(s) ER and L-GB to the handling editor at the time of review., (© 2023 Rousseau, Wu, Heffron, Baeten, Celum, Travill, Delany-Moretlwe, Bekker, Bukusi, Omollo, van der Straten, O'Malley, Haberer, Morton, Johnson and Roberts.)

The use of visible light to drive polymerizations with spatiotemporal control offers a mild alternative to contemporary UV-light-based production of soft materials. In this spectral region, photoredox catalysis represents the most efficient polymerization method, yet it relies on the use of heavy-atoms, such as precious metals or toxic halogens. Herein, spin-orbit charge transfer intersystem crossing from boron dipyrromethene (BODIPY) dyads bearing twisted aromatic groups is shown to enable efficient visible light polymerizations in the absence of heavy-atoms. A ≈5-15× increase in polymerization rate and improved photostability was achieved for twisted BODIPYs relative to controls. Furthermore, monomer polarity had a distinct effect on polymerization rate, which was attributed to charge transfer stabilization based on ultrafast transient absorption and phosphorescence spectroscopies. Finally, rapid and high-resolution 3D printing with a green LED was demonstrated using the present photosystem., (© 2023 Wiley-VCH GmbH.)

Engagement of adolescents and young adults (AYA) in HIV research is increasing in many settings. We organized a crowdsourcing open call to solicit examples of how AYA have been engaged in HIV research in Africa and to develop an engagement typology. We formed a steering committee, promoted the open call, organized judging and recognized finalists. We used a multi-methods approach to identify emerging themes and measure engagement. We received 95 entries from individuals in 15 countries; 74 met the eligibility criteria. More than three-quarters of entries were from AYA (55/74, 74%). Four themes characterized AYA engagement: (1) AYA were co-creators in the HIV research process. (2) AYA were involved in community-level capacity building. (3) AYA were co-leaders in minor risk research. (4) AYA used digital methods to enhance engagement. Our open call identified diverse methods of AYA engagement, which can enhance strategies used to reach AYA in African HIV studies., (© 2022. The Author(s).)

Adolescent mental health (AMH) is a critical driver of HIV outcomes, but is often overlooked in HIV research and programming. The implementation science Exploration, Preparation, Implementation, Sustainment (EPIS) framework informed development of a questionnaire that was sent to a global alliance of adolescent HIV researchers, providers, and implementors working in sub-Saharan Africa with the aim to (1) describe current AMH outcomes incorporated into HIV research within the alliance; (2) identify determinants (barriers/gaps) of integrating AMH into HIV research and care; and (3) describe current AMH screening and referral systems in adolescent HIV programs in sub-Saharan Africa. Respondents reported on fourteen named studies that included AMH outcomes in HIV research. Barriers to AMH integration in HIV research and care programs were explored with suggested implementation science strategies to achieve the goal of integrated and sustained mental health services within adolescent HIV programs., (© 2022. The Author(s).)

HIV and gender-based violence (GBV) are syndemic in sub-Saharan Africa and provision of support for participants who disclose GBV constitutes part of comprehensive care. Consequently, a process was undertaken to develop, implement, and evaluate standard operating procedures (SOPs) in MTN-025/HOPE, a study of the dapivirine vaginal ring for HIV prevention. The SOP was developed using needs assessment surveys in addition to World Health Organization (WHO) guidelines and other literature. Sites tailored and implemented the SOP through HOPE implementation. At study end, staff reported increased training 32/35 (91.43%); improved confidence (18/26; 69.23%); and improved vicarious trauma prevention onsite (17/28; 60.71%). Leadership reported increased staff competence in GBV response. Obstacles included limited referral organizations and time for follow-up, continued training needs, and cultural norms. Development and implementation of an SOP is a feasible strategy to build a GBV response to improve health systems and support sustained effective use of HIV prevention products., (© 2022. The Author(s).)

Research suggests that women's experience of intimate partner violence (IPV) is associated with poor engagement in HIV care and treatment. However, most studies have been cross-sectional and conducted in North America. We examined the association between physical IPV and HIV care outcomes in a prospective cohort study of women living with HIV (WLHIV) in Malawi, South Africa, Uganda, and Zimbabwe. At enrollment, 15% of the 351 participants self-reported physical IPV. IPV experience was not associated with time to first engagement in HIV care or the proportion virally suppressed after 6 months on ART. Women reporting physical IPV were less likely to initiate ART within 6 months of becoming eligible (adjusted RR 0.74, 95% CI 0.53-1.03). IPV screening is critical to identify survivors and link them to appropriate services. However, addressing IPV may not increase engagement in HIV care or viral load suppression among WLHIV in sub-Saharan Africa., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Solvated electrons are powerful reducing agents capable of driving some of the most energetically expensive reduction reactions. Their generation under mild and sustainable conditions remains challenging though. Using near-ultraviolet irradiation under low-intensity one-photon conditions coupled with electrochemical and optical detection, we show that the yield of solvated electrons in water is increased more than 10 times for nanoparticle-decorated electrodes compared to smooth silver electrodes. Based on the simulations of electric fields and hot carrier distributions, we determine that hot electrons generated by plasmons are injected into water to form solvated electrons. Both yield enhancement and hot carrier production spectrally follow the plasmonic near-field. The ability to enhance solvated electron yields in a controlled manner by tailoring nanoparticle plasmons opens up a promising strategy for exploiting solvated electrons in chemical reactions.

Semiconductor nanocrystals (NCs) interfaced with molecular ligands that function as charge and energy acceptors are an emerging platform for the design of light-harvesting, photon-upconverting, and photocatalytic materials. However, NC systems explored for these applications often feature high concentrations of bound acceptor ligands, which can lead to ligand-ligand interactions that may alter each system's ability to undergo charge and energy transfer. Here, we demonstrate that aggregation of acceptor ligands impacts the rate of photoinduced NC-to-ligand charge transfer between lead(II) sulfide (PbS) NCs and perylenediimide (PDI) electron acceptors. As the concentration of PDI acceptors is increased, we find the average electron transfer rate from PbS to PDI ligands decreases by nearly an order of magnitude. The electron transfer rate slowdown with increasing PDI concentration correlates strongly with the appearance of PDI aggregates in steady-state absorption spectra. Electronic structure calculations and molecular dynamics (MD) simulations suggest PDI aggregation slows the rate of electron transfer by reducing orbital overlap between PbS charge donors and PDI charge acceptors. While we find aggregation slows electron transfer in this system, the computational models we employ predict ligand aggregation could also be used to speed electron transfer by producing delocalized states that exhibit improved NC-molecule electronic coupling and energy alignment with NC conduction band states. Our results demonstrate that ligand aggregation can alter rates of photoinduced electron transfer between NCs and organic acceptor ligands and should be considered when designing hybrid NC:molecule systems for charge separation.

Background: The high prevalence of HIV among adolescent girls and young women aged 15-24 in Eastern and Southern Africa indicates a substantial need for accessible HIV prevention and treatment services in this population. Amidst this need, Zambia has yet to meet global testing and treatment targets among adolescent girls and young women living with HIV. Increasing access to timely, high-quality HIV services in this population requires addressing the intensified anticipated and experienced stigma that adolescent girls and young women often face when seeking HIV care, particularly stigma in the health facility setting. To better understand the multi-level drivers and manifestations of health facility stigma, we explored health workers' perceptions of clinic- and community-level stigma against adolescent girls and young women seeking sexual and reproductive health, including HIV, services in Lusaka, Zambia., Methods: We conducted 18 in-depth interviews in August 2020 with clinical and non-clinical health workers across six health facilities in urban and peri-urban Lusaka. Data were coded in Dedoose and thematically analyzed., Results: Health workers reported observing manifestations of stigma driven by attitudes, awareness, and institutional environment. Clinic-level stigma often mirrored community-level stigma. Health workers clearly described the negative impacts of stigma for adolescent girls and young women and seemed to generally express a desire to avoid stigmatization. Despite this lack of intent to stigmatize, results suggest that community influence perpetuates a lingering presence of stigma, although often unrecognized and unintended, in health workers and clinics., Conclusions: These findings demonstrate the overlap in health workers' clinic and community roles and suggest the need for multi-level stigma-reduction approaches that address the influence of community norms on health facility stigma. Stigma-reduction interventions should aim to move beyond fostering basic knowledge about stigma to encouraging critical thinking about internal beliefs and community influence and how these may manifest, often unconsciously, in service delivery to adolescent girls and young women., (© 2022. The Author(s).)

The HIV infection rate is higher among adolescent girls and young women (AGYW) in Africa than men in the same age range. Pre-exposure prophylaxis (PrEP) can be used by women discreetly; however, for most AGYW, male partner approval is desired. We explored PrEP use in the context of relationship violence and power dynamics through focus group discussions and support club sessions with AGYW, in-depth interviews and male sensitisation sessions with male partners of AGYW, and joint sessions with AGYW and their male partners. Many male partners reported hesitancy in supporting partner's PrEP use without sufficient information; most of these became supportive following their engagement in study activities; and most preferred participation in decisions around PrEP use. For AGYW, male involvement minimised partner violence around their PrEP use. The findings support the need for correct PrEP information to be provided to male partners of AGYW and to involve them early on, in decision-making about PrEP use. This is likely to improve uptake of and adherence to PrEP.

Background: Consistent use of oral pre-exposure prophylaxis (PrEP) has been a challenge among women, particularly when in relationships with lack of partner support or intimate partner violence (IPV)., Methods: We conducted a randomized controlled trial (RCT) of an empowerment counseling intervention called "CHARISMA" delivered to women within a PrEP demonstration project in Johannesburg, South Africa. The trial tested the effectiveness of CHARISMA to increase PrEP adherence; decrease social harms and IPV; and improve partnership dynamics (eg, communication, disclosure and support) compared with those who received the standard of care counselling support and referrals. Four hundred seven HIV-seronegative, nonpregnant women aged 18-45 years were enrolled for 6 months of PrEP use, with 203 randomized (1:1) to the intervention. All participants reporting IPV received counseling and referrals that followed the WHO five-step Listen, Inquire, Validate, Enhance Safety, and Support approach., Results: This RCT did not identify statistically significant differences between study arms for PrEP adherence or relationship dynamics, with the exception of an increase in PrEP disclosure among intervention arm women. In our study, we cannot determine whether the lack of detectable findings may have been because of lack of intervention effect, strength of standard of care services, low risk in the study population, or other factors., Conclusions: Addressing IPV and relationship dynamics remain important factors influencing HIV risk, and addressing these within the context of PrEP delivery is an important synergistic opportunity. CHARISMA was highly acceptable to participants, and further adaptation and testing of the intervention to other populations and settings will augment the evidence base., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The monthly dapivirine vaginal ring provides partial protection against HIV, and a longer duration ring may reduce user burden and improve adherence. We examined acceptability and preference for 3-month versus 1-month rings for HIV-1 risk reduction in a phase 1 clinical trial. Materials and Methods: In Microbicide Trials Network-036/International Partnership for Microbicides 047, 49 HIV-negative participants aged 18-45 were randomized to one of two 3-month rings or the 1-month ring. Acceptability ratings were collected at enrollment, week 4, and study exit (week 13). At exit, ring preference was assessed quantitatively among all participants and a randomly selected subset of 24 participants completed in-depth interviews. Quantitative and qualitative findings were integrated to explore factors influencing acceptability and preference. Results: Acceptability of each ring was initially moderate and increased during the trial. Ratings were lower in the 3-month ring arms than the 1-month arm at each time point, including baseline. Most participants (34/47; 72%) preferred a 3-month ring at exit; however, this proportion was significantly lower within some subgroups characterized by site, education, race/ethnicity, and experiences with ring use. Qualitative interviews revealed reservations about hygiene and safety of the 3-month ring, including discomfort with use during menses, but these were usually outweighed by its increased convenience. Conclusions: Both ring durations were highly acceptable at study exit. Although most participants preferred a 3-month ring, preference was more divided in certain subgroups, highlighting the benefit of offering different duration options. Providing additional support to address concerns about hygiene and safety may improve acceptability of a 3-month vaginal ring.

Symmetry breaking charge transfer (SBCT) is a process in which a pair of identical chromophores absorb a photon and use its energy to transfer an electron from one chromophore to the other, breaking the symmetry of the chromophore pair. This excited state phenomenon is observed in photosynthetic organisms where it enables efficient formation of separated charges that ultimately catalyze biosynthesis. SBCT has also been proposed as a means for developing photovoltaics and photocatalytic systems that operate with minimal energy loss. It is known that SBCT in both biological and artificial systems is in part made possible by the local environment in which it occurs, which can move to stabilize the asymmetric SBCT state. However, how environmental degrees of freedom act in concert with steric and structural constraints placed on a chromophore pair to dictate its ability to generate long-lived charge pairs via SBCT remain open topics of investigation.In this Account, we compare a broad series of dipyrrin dimers that are linked by distinct bridging groups to discern how the spatial separation and mutual orientation of linked chromophores and the structural flexibility of their linker each impact SBCT efficiency. Across this material set, we observe a general trend that SBCT is accelerated as the spatial separation between dimer chromophores decreases, consistent with the expectation that the electronic coupling between these units varies exponentially with their separation. However, one key observation is that the rate of charge recombination following SBCT was found to slow with decreasing interchromophore separation, rather than speed up. This stems from an enhancement of the dimer's structural rigidity due to increasing steric repulsion as the length of their linker shrinks. This rigidity further inhibits charge recombination in systems where symmetry has already enforced zero HOMO-LUMO overlap. Additionally, for the forward transfer, the active torsion is shown to increase LUMO-LUMO coupling, allowing for faster SBCT within bridging groups.By understanding trends for how rates of SBCT and charge recombination depend on a dimer's internal structure and its environment, we identify design guidelines for creating artificial systems for driving sustained light-induced charge separation. Such systems can find application in solar energy technologies and photocatalytic applications and can serve as a model for light-induced charge separation in biological systems.

Biomedical, female-initiated HIV prevention methods can help reduce disproportionately high HIV rates among women in sub-Saharan Africa, but male partner resistance and intimate partner violence (IPV) may impact ability to ensure effective use. To support consistent use of the dapivirine vaginal ring (VR), we pilot-tested the impact of the CHARISMA relationship counseling intervention ("CHARISMA") with women enrolled in the multi-site open-label Microbicide Trials Network (MTN) 025/HOPE trial at the Wits Reproductive Health and HIV Research Institute (Wits RHI) site in Johannesburg, South Africa. Lay counselors used a 42-item tool with five subscales to assess relationships and IPV and provide tailored counseling at enrolment, followed by a booster counselling session at Month 1 and follow-up checks at Months 3 and 6. We evaluated potential impact by examining self-reported ring disclosure to partners, partner clinic attendance, self-reported incident social harms (SH) and IPV, and biomarkers of ring adherence at Wits RHI. We subsequently compared these outcomes at three comparator HOPE study sites using multivariable regression models. Comparator study sites were purposively selected as those most similar to Wits RHI for baseline characteristics identified a priori. At Wits RHI, 95 of 96 (99%) HOPE participants enrolled into the CHARISMA pilot study. Mean age was 30, 36.8% lived with a partner, and 85.3% received their partner's financial support. During the six months of pilot study follow-up, participants reported: ring use disclosure to partners at 72.7% visits; 4.3% partners attending the research clinic; one partner-related SH; and 9.5% experienced incident IPV. The mean level of dapivirine released from returned used rings was 3.4 mg (SD 1.56), suggesting moderate adherence. Participants in the CHARISMA pilot had high background prevalence and incidence of IPV but were nevertheless able to adhere to ring use, and some male partners came to the research clinic. In adjusted regression models, compared to Wits RHI, partner clinic attendance was lower at all comparator sites; and significantly so at Site A (aRR 0.12, 95% CI 0.00-0.98). Sites B and C had lower levels of dapivirine released (suggesting lower adherence), but this difference was not significant. Site B women were more likely to report ring disclosure to partners at FU visits (aRR 1.12, 95% CI 1.00-1.25). IPV reported during follow-up was significantly lower at Site B (aRR 0.20, 95% CI 0.04-0.98, p = 0.047). CHARISMA taught women skills to decide on levels of ring-use disclosure to partners or others; therefore it is difficult to interpret differences in ring disclosure to partners with other sites. Similarly, CHARISMA heightened participants' awareness of abuse, possibly increasing IPV reports. Testing CHARISMA under fully-powered controlled conditions will improve understanding of its impact on women's relationships and ability to use female-initiated HIV prevention methods., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Semiconductor nanocrystals (NCs) have emerged as promising photocatalysts. However, NCs are often functionalized with complex ligand shells that contain not only charge acceptors but also other "spectator ligands" that control NC solubility and affinity for target reactants. Here, we show that spectator ligands are not passive observers of photoinduced charge transfer but rather play an active role in this process. We find the rate of electron transfer from quantum-confined PbS NCs to perylenediimide acceptors can be varied by over a factor of 4 simply by coordinating cinnamate ligands with distinct dipole moments to NC surfaces. Theoretical calculations indicate this rate variation stems from both ligand-induced changes in the free energy for charge transfer and electrostatic interactions that alter perylenediimide electron acceptor orientation on NC surfaces. Our work shows NC-to-molecule charge transfer can be fine-tuned through ligand shell design, giving researchers an additional handle for enhancing NC photocatalysis.

Youth-friendly health care delivery models are needed to address the complex health care needs of adolescent girls and young women (AGYW). The aim of this study is to explore the lived experiences of AGYW seeking comprehensive HIV and sexual and reproductive health (SRH) care and to elicit their preferences for integrated health care services. We conducted in-depth interviews and focus group discussions in Lusaka, Zambia among 69 AGYW aged 10-20 who were HIV-negative or of unknown status and 40 AGYW aged 16-24 living with HIV. The data were coded through deductive and inductive processes and analyzed thematically using modified World Health Organization (WHO) dimensions of quality for youth-friendly services. AGYW expressed preference for one-stop clinics with integrated services that could provide HIV services along with other services such as pregnancy testing and family planning. AGYW also wanted information on staying healthy and approaches to prevent disease which could be delivered in the community setting such as youth clubs. An integrated clinic should address important attributes to AGYW including short wait time, flexible opening hours, assurance of confidentiality and positive staff attitudes. Youth-friendly, integrated care delivery models that incorporate AGYW preferences may foster linkages to care and improve outcomes among vulnerable AGYW., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Edwards, Roberts, Chelwa, Phiri, Nyblade, Mulenga, Brander, Musheke, Mbizvo and Subramanian.)