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The combination of gas-phase oxygen abundances and stellar metallicities can provide us with unique insights into the metal enrichment histories of galaxies. In this work, we compare the stellar and gas-phase metallicities measured within a 1 Re aperture for a representative sample of 472 star-forming galaxies extracted from the SAMI Galaxy Survey. We confirm that the stellar and interstellar medium (ISM) metallicities are strongly correlated, with scatter ∼3 times smaller than that found in previous works, and that integrated stellar populations are generally more metal-poor than the ISM, especially in low-mass galaxies. The ratio between the two metallicities strongly correlates with several integrated galaxy properties including stellar mass, specific star formation rate, and a gravitational potential proxy. However, we show that these trends are primarily a consequence of: (a) the different star formation and metal enrichment histories of the galaxies, and (b) the fact that while stellar metallicities trace primarily iron enrichment, gas-phase metallicity indicators are calibrated to the enrichment of oxygen in the ISM. Indeed, once both metallicities are converted to the same 'element base' all of our trends become significantly weaker. Interestingly, the ratio of gas to stellar metallicity is always below the value expected for a simple closed-box model, which requires that outflows and inflows play an important role in the enrichment history across our entire stellar mass range. This work highlights the complex interplay between stellar and gas-phase metallicities and shows how care must be taken in comparing them to constrain models of galaxy formation and evolution. [ABSTRACT FROM AUTHOR]

Subcellular compartmentalization of metabolic enzymes establishes a unique metabolic environment that elicits specific cellular functions. Indeed, the nuclear translocation of certain metabolic enzymes is required for epigenetic regulation and gene expression control. Here, we show that the nuclear localization of the mitochondrial enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) ensures mitosis progression. Nuclear MTHFD2 interacts with proteins involved in mitosis regulation and centromere stability, including the methyltransferases KMT5A and DNMT3B. Loss of MTHFD2 induces severe methylation defects and impedes correct mitosis completion. MTHFD2 deficient cells display chromosome congression and segregation defects and accumulate chromosomal aberrations. Blocking the catalytic nuclear function of MTHFD2 recapitulates the phenotype observed in MTHFD2 deficient cells, whereas restricting MTHFD2 to the nucleus is sufficient to ensure correct mitotic progression. Our discovery uncovers a nuclear role for MTHFD2, supporting the notion that translocation of metabolic enzymes to the nucleus is required to meet precise chromatin needs., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Nuclear metabolism and DNA damage response are intertwined processes, but the precise molecular links remain elusive. Here, we explore this crosstalk using triple-negative breast cancer (TNBC) as a model, a subtype often prone to DNA damage accumulation. We show that the de novo purine synthesis enzyme IMPDH2 is enriched on chromatin in TNBC compared to other subtypes. IMPDH2 chromatin localization is DNA damage dependent, and IMPDH2 repression leads to DNA damage accumulation. On chromatin, IMPDH2 interacts with and modulates PARP1 activity by controlling the nuclear availability of NAD + to fine-tune the DNA damage response. However, when IMPDH2 is restricted to the nucleus, it depletes nuclear NAD + , leading to PARP1 cleavage and cell death. Our study identifies a non-canonical nuclear role for IMPDH2, acting as a convergence point of nuclear metabolism and DNA damage response., Competing Interests: Competing interests The author declares no competing interests., (© 2024. The Author(s).)

The on-surface synthesis of an isomer of undecacene, bearing two four-membered rings and two para-quinodimethane moieties, starting from a tetramethyl-substituted diepoxy precursor, is presented. The transformation implies a thermal double deoxygenation followed by a stepwise double dehydrogenation reaction on the Au(111) surface, locally induced by inelastic tunneling electrons. This results in the transformation of para-dimethylbenzene moieties into non-aromatic para-quinodimethanes. The structures and electronic properties of the intermediate and final products are investigated at the single molecule level with high spatial resolution, using both scanning tunneling microscopy/spectroscopy and non-contact atomic force microscopy. The experimental results are supported by density functional theory calculations., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Submonolayer amounts of chloroaluminum-phthalocyanine on Cu(100) were studied with scanning tunneling spectroscopy. The molecule can be prepared in a fourfold symmetric state whose conductance spectrum exhibits a zero-bias feature similar to a Kondo resonance. In magnetic fields, however, this resonance splits far more than expected from the spin of a single electron. Density functional theory calculations reveal a charge transfer of 1.3 electrons to the degenerate lowest unoccupied molecular orbitals. These orbitals are mixed by the orbital momentum operator L[over ^]_{z} with a large matrix element corresponding to m_{L}≈2.7. Dehydrogenation of a ligand lifts the degerenracy of the lowest unoccupied molecular orbital, reduces the splitting in magnetic fields, and induces a polarity dependence of the spectra. Using model calculations of the spin, orbital, and vibrational degrees of freedom we show that a dynamical Jahn-Teller effect reproduces the main experimental observations.

This paper describes the results of the study I Want More! The Lives of Sex Workers During the COVID-19 Pandemic, which is part of the EPIC community research program. The study analyzed the effects of the pandemic on the lives of cis, trans and travesti sex workers in nine Brazilian states and 11 cities throughout 2020 and 2021. This article focuses on the qualitative component of the study, which was based on semi-structured, remote and face-to-face interviews carried out with 43 sex workers, and its comparison with the quantitative component. The effects are analyzed in relation to the Brazilian pandemic framework, considering the social, economic and political dimensions of the COVID-19 virus. Some of the key themes of the analysis are cases of illness, specific social isolation practices, prevention and care management practices, individual vaccination and collective vaccination strategies. We also share the daily and activist responses drawn up by sex workers in a political agenda that opposes the individualistic, familialist, domestic, and neoliberal logic of isolation by adopting community care perspectives, which was the only line of health action for this work category during the pandemic. Collective actions reposition sex work at the interface between public health and human rights and take as their principle the "street knowledge", from activism, and the workers' power of decision over their own bodies.

Background In Latin American countries and Suriname, sexual transmission is one of the most common modes of HIV transmission, and men who have sex with men (MSM) who engage in sex work constitute a key population. Methods In a sample of MSM (N =53,166) from the Latin American Internet Survey (2018) across 18 countries, we examined how sex work engagement is associated with syndemic conditions (multidrug use, homophobic abuse, depression/anxiety, alcohol dependency (CAGE alcohol questionnaire) and internalised homonegativity) and condomless anal intercourse with non-steady male partners using separate logistic regressions. We then used a structural equation model to determine if and how syndemic conditions mediate the relationship between sex work engagement and non-steady male partners. Results We found that getting paid for sex was associated with less condom use for anal intercourse with non-steady male partners and particular syndemic conditions, such as multidrug use, homophobic abuse and alcohol dependency. In our structural equation model, the results showed that the direct relationship between sex work engagement and non-steady male partners was positive and significant, and syndemic conditions partially mediated this relationship. Conclusion Our results highlight the continuing need for including MSM who engage in sex work and those who experience syndemic conditions in the prevention strategies targeted to MSM in Latin America and Suriname, to prevent the transmission of HIV.

The COVID-19 crisis had a global impact and many marginalised groups, such as people who use or inject drugs, are more vulnerable to the SARS-CoV-2 virus and its consequences due to their pre-existing health inequalities. Moreover, people who use/inject drugs are also criminalised in some countries such as Algeria. This analysis aimed to explore the psychosocial experience of the COVID-19 crisis among people who use/inject drugs in Algeria. Twenty-nine qualitative interviews were conducted in 2021 with a community-based approach. Results of the thematic content analysis showed the intersectional effects of the COVID-19 crisis among people who use or inject drugs through the experience of a double crisis: one related to COVID-19 and the second to their specific difficulties related to drug use. Addressing social inequalities in health of people who use or inject drugs, through better recognition of their rights and needs, is crucial to improving their health., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

With a national prevalence of 0.9%, Burundi is close to achieving UNAIDS' 2025 targets. Despite this, different types of crises periodically disrupt its HIV health services. The community-based program EPIC measured the impact of the COVID-19 health crisis on people living with HIV (PLHIV) in Burundi in 2021. Specifically, it assessed ART interruption and associated factors since the beginning of the pandemic. The study questionnaire was administered to PLHIV in three cities between October and November 2021. Participants were recruited using convenience sampling. Logistic regression models helped identify factors associated with ART interruption. Of the 317 respondents, 37 (11.7%) reported interruption. The majority (79.2%) self-identified as belonging to key populations. Interruption was significantly associated with: fewer HIV medical follow-up visits (adjusted Odds Ratio, aOR = 7.80, p = 0.001) and forced HIV status disclosure (aOR = 4.10, p = 0.004). It was inversely associated with multi-month ART dispensing (aOR = 0.36, p = 0.017) since the beginning of the pandemic and the perception of not having been sufficiently informed by the HIV medical team about the risk of COVID-19 infection (aOR = 0.11, p < 0.001). Our results highlight the importance of multi-month ART dispensing, enhanced communication, and voluntary disclosure of one's HIV status in preventing ART interruption in times of crises in Burundi., (© 2024. The Author(s).)

Chemsex is defined as use of psychoactive drugs with the aim of having sexual relations between gay men, bisexuals and men who have sex with men for a long period of time. To study this phenomenon, this qualitative descriptive study was proposed with the objective of describing the practice of chemsex from the perspective of users, to determine the main factors associated with its practice, the perception of the impact on their health and to establish prevention needs. Data were obtained using conversational techniques: 12 semi-structured interviews and 3 focus groups. The purposive sample was made up of GBMSM with a mean age of 40.1 years, 78% born in Spain, and 68% with completed university studies. The qualitative analysis focused on three thematic areas: factors associated with the practice of chemsex, the impact of chemsex on health, and prevention and risk reduction needs. It is concluded that the practice of chemsex should be understood as multifactorial and multicausal, associated with the sociocultural context. Sexual satisfaction, increased libido and the search for more intense pleasure are identified as key factors among people who practice it. These men are still scared of being judged, even by specialists who may lack knowledge or training. A reanalysis and rethinking of the interventions and policies directed towards this population is necessary, putting the focus of action on shared decision-making, self-care, cultural competence and the humanization of care.

Magnetometry plays a pivotal role in addressing the requirements of ultradense storage technology and overcoming challenges associated with downscaled spin qubits. A promising approach for atomic-scale single-spin sensing involves utilizing a magnetic molecule as a spin sensor, although such a realization is still in its early stages. To tackle this challenge and underscore the potential of this method, we combined a nickelocene molecule with scanning tunneling microscopy to perform versatile spin-sensitive imaging of magnetic surfaces. We investigated model Co islands on Cu(111) of different thicknesses having variable magnetic properties. Our method demonstrates robustness and reproducibility, providing atomic-scale sensitivity to spin polarization and magnetization orientation, owing to a direct exchange coupling between the nickelocene-terminated tip and the Co surfaces. We showcase the accessibility of magnetic exchange maps using this technique, revealing unique signatures in magnetic corrugation, which are well described by computed spin-density maps. These advancements significantly improve our capacity to probe and visualize magnetism at the atomic level.

Community-based research, that is, the meaningful involvement of affected populations in the production of scientific knowledge that concerns them, is a political struggle and an ethical necessity. Coalition PLUS, an international network of organizations (most of them NGOs) fighting against HIV and hepatitis, created a community-based research laboratory (CBRL) composed of people from more than sixteen countries and various disciplinary fields. The objectives of the CBLR are to build research capacity, ensure collaboration with local and international academic research centers, and develop international research projects. The CBRL acts as a bridge between different partners, reconciling sometimes divergent interests, and must provide mediation and support to promote dialogue, transparency, and a relationship of trust between the communities and academic researchers. However, the need for scientific legitimacy obliges us to continuously seek a balance between responding to the needs of the field and using rigorous scientific methods, while optimizing and prioritizing existing resources. The permanent quest for this balance has led the CBRL to reorganize its mode of operation to optimize existing synergies with academic research laboratories, with a view to asserting its scientific legitimacy and continuing to contribute to social transformation through community-based research that is both innovative and of high quality. This paper provides a critical reflection on the issues, challenges, practices, and solutions of community-based research within the Coalition PLUS network.

Little is known about the adaption of community-based organizations (CBOs) during the COVID-19 crisis. This study aimed to study how HIV CBOs and their community health workers (CHWs) faced the COVID-19 outbreak. Semi-structured interviews (n = 53) were conducted among CHWs in Burundi, Mauritania, and Lebanon in 2021. A thematic content analysis was performed. Results showed that CBOs had succeeded in maintaining HIV services and integrated COVID-19 prevention and awareness in their activities. COVID-19 led to innovation in terms of HIV services (eg, telemedicine and online psychosocial support) and to opportunities to try new modalities of antiretroviral therapy dispensation. Field workers (a specific group among CHWs) were negatively impacted by the COVID-19 crisis and showed resilience in their adaptation to ensure the continuity of their activities. Considering the essential role of field workers during the crisis, their status and the sustainability of their activities should be clearly supported by health policies and programs., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Information concerning the impact of the COVID-19 health crisis on populations most affected by HIV and hepatitis C virus (HCV; or key populations [KP]), and those working with these populations in community settings, is limited. Community-based organizations working in the field of HIV and viral hepatitis are well placed to identify and meet the new needs of KP owing to the health crisis., Objective: This study aims to describe the development and implementation of an exploratory and descriptive multicountry, community-based research program, EPIC (Enquêtes Pour évaluer l'Impact de la crise sanitaire covid en milieu Communautaire), within an international network of community-based organizations involved in the response to HIV and viral hepatitis. The EPIC program aimed to study the impact of the COVID-19 health crisis on KP or people living with HIV or HCV and people working with these populations at the community level (community health workers [CHWs]) and to identify the key innovations and adaptations in HIV and HCV services., Methods: A general protocol and study documents were developed and shared within the Coalition PLUS network. The protocol had a built-in flexibility that allowed participating organizations to adapt the study to local needs in terms of the target population and specific themes of interest. Data were collected using surveys or interviews., Results: From July 2020 to May 2022, a total of 79 organizations participated in the EPIC program. Across 32 countries, 118 studies were conducted: 66 quantitative (n=12,060 among KP or people living with HIV or people living with HCV and n=811 among CHWs) and 52 qualitative (n=766 among KP or people living with HIV or people living with HCV and n=136 among CHWs)., Conclusions: The results of the EPIC program will provide data to describe the impact of the health crisis on KP and CHWs and identify their emerging needs. Documentation of innovative solutions that were put into place in this context may help improve the provision of services after COVID-19 and for future health crises., International Registered Report Identifier (irrid): DERR1-10.2196/45204., (©Rosemary M Delabre, Marion Di Ciaccio, Nicolas Lorente, Virginie Villes, Juliana Castro Avila, Adam Yattassaye, César Bonifaz, Amal Ben Moussa, Ingrid-Zaïre Sikitu, Niloufer Khodabocus, Rosa Freitas, Bruno Spire, Maria Amélia Veras, Luis Sagaon-Teyssier, Gabriel Girard, Perrine Roux, Annie Velter, Valérie Delpech, Jade Ghosn, Lucas Riegel, Daniela Rojas Castro. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 14.12.2023.)

Introduction: Community health workers (CHW) were integral in the COVID-19 response, particularly concerning services for populations vulnerable to HIV. Little is known regarding the mental health of CHW during the COVID-19 crisis. The objective of this study was to study resilience of CHW working in HIV non-governmental organizations., Methods: An anonymous online, cross-sectional questionnaire was implemented during 2021 among CHW in Benin, Colombia, Guatemala, and Spain. Three scales were used to assess mental health: the 6-item Brief-Resilience Scale, the 9-item Patient Scale Questionnaire and the 7-item Generalized-Anxiety-Disorder scale. Logistic regression models were used to identify factors associated with "low" resilience vs "normal" or "high" resilience., Results: Among 295 respondents, the median standardized resilience score was 58.33 (IQR = [50.0-75.0], n = 267), 18.52 (IQR = [7.4-33.3], n = 282) for standardized depression score and 19.05 (IQR = [4.8-33.3], n = 274) for standardized anxiety score. Standardized resilience score was negatively correlated with standardized anxiety score (rho = -0.49, p < 0.001, n = 266) and standardized depression score (rho = -0.44, p < 0.001, n = 267)., Conclusions: Normal or high level of resiliency in the HIV CHW were observed during the COVID-19 crisis. Self-efficacy, through COVID-19 prevention training, was a factor associated with resilience. Health policy must place CHW at the core of the healthcare system response to Covid-19 and to future health emergencies, as they ensure continuity of care for many diseases including HIV among vulnerable populations., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier B.V.)

While cellular metabolism impacts the DNA damage response, a systematic understanding of the metabolic requirements that are crucial for DNA damage repair has yet to be achieved. Here, we investigate the metabolic enzymes and processes that are essential for the resolution of DNA damage. By integrating functional genomics with chromatin proteomics and metabolomics, we provide a detailed description of the interplay between cellular metabolism and the DNA damage response. Further analysis identified that Peroxiredoxin 1, PRDX1, contributes to the DNA damage repair. During the DNA damage response, PRDX1 translocates to the nucleus where it reduces DNA damage-induced nuclear reactive oxygen species. Moreover, PRDX1 loss lowers aspartate availability, which is required for the DNA damage-induced upregulation of de novo nucleotide synthesis. In the absence of PRDX1, cells accumulate replication stress and DNA damage, leading to proliferation defects that are exacerbated in the presence of etoposide, thus revealing a role for PRDX1 as a DNA damage surveillance factor., (© 2023 The Authors. Published under the terms of the CC BY 4.0 license.)

The magnetic properties of transition-metal ions are generally described by the atomic spins of the ions and their exchange coupling. The orbital moment, usually largely quenched due the ligand field, is then seen as a perturbation. In such a scheme, S = 1/2 ions are predicted to be isotropic. We investigate a Co(II) complex with two antiferromagnetically coupled 1/2 spins on Au(111) using low-temperature scanning tunneling microscopy, X-ray magnetic circular dichroism, and density functional theory. We find that each of the Co ions has an orbital moment comparable to that of the spin, leading to magnetic anisotropy, with the spins preferentially oriented along the Co-Co axis. The orbital moment and the associated magnetic anisotropy is tuned by varying the electronic coupling of the molecule to the substrate and the microscope tip. These findings show the need to consider the orbital moment even in systems with strong ligand fields. As a consequence, the description of S = 1/2 ions becomes strongly modified, which have important consequences for these prototypical systems for quantum operations.

Thioether polymers are fundamental for a variety of applications. Their synthesis is, however, more challenging than that of other metal-catalyzed reactions due to the reported detachment of the S atom during thermal activation. In this study, it has been demonstrated unambiguously that thermal annealing results in the thioetherification of the 4-bromo-4-mercaptobiphenyl molecule (Br-MBP) adsorbed on the surface of Au(111). Through complementary techniques, such as scanning tunneling microscopy, spectroscopy, and first-principle calculations, we have identified four reaction steps, involving sulfhydryl or bromine molecular functional groups and leading to the formation of intermolecular C-S bonds. To form the thioether polymer and to overcome the competitive formation of C-C bonds, two reaction steps, the dehalogenation, and dissociation of the S-Au bond, must occur simultaneously. We detail the electronic properties of the phenyl-sulfur bond and the polymer as a function of the ligand length. This result suggests a wider perspective of this chemical synthesis.

Depending on its adsorption conformation on the Au(111) surface, a zwitterionic single-molecule machine works in two different ways under bias voltage pulses. It is a unidirectional rotor while anchored on the surface. It is a fast-drivable molecule vehicle (nanocar) while physisorbed. By tuning the surface coverage, the conformation of the molecule can be selected to be either rotor or nanocar. The inelastic tunneling excitation producing the movement is investigated in the same experimental conditions for both the unidirectional rotation of the rotor and the directed movement of the nanocar.

While it is well known that expression levels of metabolic enzymes regulate the metabolic state of the cell, there is mounting evidence that the converse is also true, that metabolite levels themselves can modulate gene expression via epigenetic modifications and transcriptional regulation. Here we focus on the one-carbon metabolic pathway, which provides the essential building blocks of many classes of biomolecules, including purine nucleotides, thymidylate, serine, and methionine. We review the epigenetic roles of one-carbon metabolic enzymes and their associated metabolites and introduce an interactive computational resource that places enzyme essentiality in the context of metabolic pathway topology. Therefore, we briefly discuss examples of metabolic condensates and higher-order complexes of metabolic enzymes downstream of one-carbon metabolism. We speculate that they may be required to the formation of transcriptional condensates and gene expression control. Finally, we discuss new ways to exploit metabolic pathway compartmentalization to selectively target these enzymes in cancer., Competing Interests: Declaration of interest The authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Despite men-who-have-sex-with-men (MSM) from Latin America (LA) are still a vulnerable population for known health-related conditions and social problems, availability of comparable data across LA countries for assessment and monitoring purposes is limited. The objective of this article is to present the study design and the questionnaire of LAMIS-2018 (Latin America MSM Internet Survey), its recruitment strategy, rates and sources by country, and the lessons learned from its implementation. LAMIS-2018 was a cross-sectional, internet-based survey targeting MSM living in 18 LA countries (Argentina, Bolivia, Brazil, Chile, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Paraguay, Peru, Suriname, Uruguay, and Venezuela) that gathered data about sexual behaviors, HIV/STI and viral hepatitis knowledge, prophylactic use of antiretrovirals, psychosocial health, and access to sexual health services. The survey went online for four months and was available in three languages (Spanish, Portuguese, and Dutch). Promotion was carried out using dating apps, websites, social networks, and by community-based and academic organizations of each participating country directly in gay venues and in their own premises. Overall, 64,655 MSM participated in LAMIS-2018. Dating apps and websites were the most important recruitment source in most countries, except for Honduras, Nicaragua, and Suriname, where community-based organizations recruited most of the participants. Beyond the LAMIS-2018 implementation description, we highlight the feasibility of such a study in this context, based on the collaboration between community-based and academic organizations to obtain a large sample of MSM in the region. LAMIS-2018 data will contribute to identify determinants of risk behaviors and prevention needs of vulnerable MSM populations in each country of the region., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Reyes-Díaz 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.)

Magnetism is typically associated with d- or f-block elements, but can also appear in organic molecules with unpaired π-electrons. This has considerably boosted the interest in such organic materials with large potential for spintronics and quantum applications. While several materials showing either d/f or π-electron magnetism have been synthesized, the combination of both features within the same structure has only scarcely been reported. Open-shell porphyrins (Pors) incorporating d-block transition metal ions represent an ideal platform for the realization of such architectures. Herein, the preparation of a series of open-shell, π-extended Pors that contain magnetically active metal ions (i.e., Cu II , Co II , and Fe II ) through a combination of in-solution and on-surface synthesis is reported. A detailed study of the magnetic interplay between π- and d-electrons in these metalloPors has been performed by scanning probe methods and density functional theory calculations. For the Cu and FePors, ferromagnetically coupled π-electrons are determined to be delocalized over the Por edges. For the CoPor, the authors find a Kondo resonance resulting from the singly occupied Co II d z 2 orbital to dominate the magnetic fingerprint. The Fe derivative exhibits the highest magnetization of 3.67 μ B (S≈2) and an exchange coupling of 16 meV between the π-electrons and the Fe d-states., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Electron paramagnetic resonance (EPR) can provide unique insight into the chemical structure and magnetic properties of dopants in oxide and semiconducting materials that are of interest for applications in electronics, catalysis, and quantum sensing. Here, we demonstrate that EPR in combination with scanning tunneling microscopy (STM) allows for probing the bonding and charge state of alkali metal atoms on an ultrathin magnesium oxide layer on a Ag substrate. We observe a magnetic moment of 1 μ B for Li 2 , LiNa, and Na 2 dimers corresponding to spin radicals with a charge state of +1 e . Single alkali atoms have the same charge state and no magnetic moment. The ionization of the adsorbates is attributed to charge transfer through the oxide to the metal substrate. Our work highlights the potential of EPR-STM to provide insight into dopant atoms that are relevant for the control of the electrical properties of surfaces and nanodevices.

In 2020, the COVID-19 health crisis affected all regions of the world, not sparing people already vulnerable to other viral epidemics such as HIV or HCV and/or those in precarious or socially marginalized situations. This is particularly the case for drug users or sex workers.Coalition PLUS, a network of associations fighting against HIV and viral hepatitis which defends and promotes the community-based approach, and its partners, have set up a multi-country community-based research project aimed at documenting the impact of the health crisis on the fight against HIV and viral hepatitis (key populations and community workers/activists), as well as the community responses put in place (EPIC survey).The objective of this paper is to reflect on the implementation of this community-based research study during the COVID-19 health crisis, and in particular the unforeseen difficulties to which the community-based research process had to confront and adapt. The goal is to draw lessons on what worked (and what did not work) in order to capitalize on community-based research practices during this pandemic and subsequently, facilitate the implementation of new research projects in similar contexts.