A charge dependent long-ranged force drives tailored assembly of matter in solution

The interaction between charged objects in solution is generally expected to recapitulate two central principles of electromagnetics: (i) like-charged objects repel, and (ii) they do so regardless of the sign of their electrical charge. Here we demonstrate experimentally that the solvent plays a hitherto unforeseen but crucial role in interparticle interactions, and importantly, that interactions in the fluid phase can break charge-reversal symmetry. We show that in aqueous solution, negatively charged particles can attract at long range while positively charged particles repel. In solvents that exhibit an inversion of the net molecular dipole at an interface, such as alcohols, we find that the converse can be true: positively charged particles may attract whereas negatives repel. The observations hold across a wide variety of surface chemistries: from inorganic silica and polymeric particles to polyelectrolyte- and polypeptide-coated surfaces in aqueous solution. A theory of interparticle interactions that invokes solvation at an interface explains the observations. Our study establishes a specific and unanticipated mechanism by which the molecular solvent may give rise to a strong and long-ranged force in solution, with immediate ramifications for a variety of particulate and molecular processes including tailored self-assembly, gelation and crystallization, as well as biomolecular condensation, coacervation and phase segregation. These findings also shed light on the solvent-induced interfacial electrical potential - an elusive quantity in electrochemistry and interface science implicated in many natural and technological processes, such as atmospheric chemical reactions, electrochemical energy storage and conversion, and the conduction of ions across cell membranes.Comment: 20 pages, 6 figure

Sources of influence on pregnant women's preferred mode of delivery in Buenos Aires, Argentina

Background: Understanding influences on women's preferred delivery mode is vital for planning interventions to reduce cesarean rates and for ensuring that women receive correct information. Our objectives were to: determine if sources of information influencing a pregnant woman's preferred delivery mode and knowledge of cesarean indications differ by sociodemographic characteristics; to conduct a factor analysis of items related to information sources influencing this preference; and to determine if knowledge differs by information sources influencing this preference or their underlying latent constructs. Methods: Data from a prospective cohort study conducted in Buenos Aires was analyzed. Healthy nulliparous women aged 18-35, at >32 weeks of gestation and with live, singleton pregnancies participated. The primary research questions were evaluated using Chi-square tests, factor analysis, logistic regression, and generalized estimating equations. Results: A total of 382 women participated in the study. Women of lower socioeconomic status were more influenced by people, magazines and TV/movies in their mode of delivery preferences, and had poorer knowledge of cesarean indications. Sources of influence for preferred delivery mode and factors derived in factor analysis were not associated with knowledge level when considered individually or together, or when adjusted for sociodemographic characteristics, or when accounting for clustering by the hospital sector (public or private). Conclusions: Higher socioeconomic status is associated with being less influenced by people and with better knowledge of indications for cesarean delivery. Knowledge of cesarean indications was not associated with the source of information about mode of delivery preferences.Fil: Amyx, Melissa Michele. University of Tulane; Estados UnidosFil: Gibbons, Luz. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Pque. Centenario. Centro de Investigaciones En Epidemiología y Salud Publica. Instituto de Efectividad Clinica y Sanitaria. Centro de Investigaciones En Epidemiología y Salud Publica.; ArgentinaFil: Xiong, Xu. University of Tulane; Estados UnidosFil: Mazzoni, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Pque. Centenario. Centro de Investigaciones En Epidemiología y Salud Publica. Instituto de Efectividad Clinica y Sanitaria. Centro de Investigaciones En Epidemiología y Salud Publica.; ArgentinaFil: Althabe, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Pque. Centenario. Centro de Investigaciones En Epidemiología y Salud Publica. Instituto de Efectividad Clinica y Sanitaria. Centro de Investigaciones En Epidemiología y Salud Publica.; ArgentinaFil: Buekens, Pierre. University of Tulane; Estados UnidosFil: Belizan, Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Pque. Centenario. Centro de Investigaciones En Epidemiología y Salud Publica. Instituto de Efectividad Clinica y Sanitaria. Centro de Investigaciones En Epidemiología y Salud Publica.; Argentin

Radical housing (dis)encounters: reframing housing research and praxis

We came to this issue before the outbreak of Covid-19, and we release it amidst what feels like an entirely new, and yet also entirely known world-order—a place of multiple and multiplying crises that existed before the pandemic and continue, relentlessly, to render certain people, bodies and homes disposable. It is against this cruelty, but also with a renewed sense of radical hope in justice everywhere, that RHJ first came to be. The majority of contributions to Issue 2.2 emerge from a long process of designing and selecting participants for the event Radical Housing Encounters: translocal conversations on knowledge and praxis. This event was meant to take place in person, in three separate locations simultaneously, at the end of May 2020. Through it, we sought to define and re-define radical housing knowledge and practice, paying particular attention to diverse methodological, theoretical and ethical approaches deployed in both research and militant practice around the globe. While disappointed that the event could not take place as originally planned, its rationale and ethics of care are central to the making of this issue and are reflected in the texts of its contributors as well as the process of organising the issue

Effectiveness of an internet-delivered intervention for generalized anxiety disorder in routine care: A randomised controlled trial in a student population

AbstractBackgroundCognitive behavioural therapy is one of the main and preferred treatments for generalized anxiety disorder. Numerous barriers can hinder an individual from seeking or receiving appropriate treatment; internet-delivered CBT interventions offer a relatively new means of increasing access to treatment.MethodsA service-based effectiveness randomised waiting list control trial examined the impact of an internet-delivered CBT intervention, Calming Anxiety, amongst Irish university students (N=137). Primary outcome was self-reported GAD and secondary outcomes included depression and work and social functioning.ResultsAnalyses returned inconclusive results. Both treatment and waiting list conditions displayed significant decreases in anxiety symptoms post-treatment, but we did not observe a significant between-group effect (p=0.076). Significant within-group differences from pre to post time points were observed for depression (BDI-II) and work and social functioning (WASA), and between group differences were also significant for depression (d=0.46) and functioning (d=0.36). Both groups demonstrated cases of remission and recovery from anxiety, however differences in the number of cases reaching clinically meaningful change between conditions were non-significant.ConclusionsSeveral explanations regarding the results are presented, examining issues related to active waiting lists, study limitations and treatment expectancies.Trial registration: Current Controlled Trials ISRCTN16303842

Factors associated with postpartum depression in women from low socioeconomic level in Argentina: A hierarchical model approach

Purpose to estimate the prevalence of depression at 4-week postpartum using the Edinburgh postpartum Depression Scale (EPDS) in women who delivered in a public maternity hospital in Argentina. Methods This prospective cohort study was carried out from March to August 2016 in northwest Argentina. Eligibility included delivering a singleton live birth 28 weeks of gestational age or over, 18 years or older and resided within 1 h from the maternity hospital. Women were excluded if they or their newborn were in the intensive care unit. We defined a positive screening as an EPDS score of 10 or higher or a positive response to item 10, which indicates thoughts of self-harm. Results A total of 587 women were enrolled and 539 women completed the home visit interview and the EPDS. A total of 167 (31.0%, 95% CI 27.1?35.1) mothers screened positive in the EPDS using a score ≥ 10 and 99 (18.4%, 95% CI 15.1?21.6%) using a score ≥ 13, which indicate increased severity of depressive symptoms. In both cases, the 23 (4.3%) women that responded as having thoughts of self-harm were included. Conclusion Nearly a third of women who participated had depressive symptoms at four weeks postpartum in a public hospital in Tucumán, Argentina. Socio-demographic, particularly personal psychiatric history, factors and social and cultural influences can impact results. Our results highlight the need for improved screening and better diagnostic tool for women with postpartum depression in Argentina and to investigate the impact of postpartum depressive symptoms on women´s health and their families.Fil: Pham, Diana. University of Texas; Estados UnidosFil: Cormick, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; Argentina. University of Cape Town. Faculty of Health Sciences. Department of Human Biology; SudáfricaFil: Amyx, Melissa Michele. University of Tulane; Estados UnidosFil: Gibbons, Luz. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Doty, Meitra. University of Texas; Estados UnidosFil: Brown, Asia. University of Yale; Estados UnidosFil: Norwood, Angel. Xavier University of Louisiana. Department of Psychology; Estados UnidosFil: Daray, Federico Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Cátedra de Farmacología; ArgentinaFil: Althabe, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: Belizan, Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; Argentin

Outcomes and costs of primary care surveillance and intervention for overweight or obese children: the LEAP 2 randomised controlled trial

Objective To determine whether ascertainment of childhood obesity by surveillance followed by structured secondary prevention in primary care improved outcomes in overweight or mildly obese children

Evaluacija inovativno digitalno kontroliranog Er:YAG lasera u liječenju leukoplakije - probno istraživanje

The use of lasers for treatment of oral leukoplakia has gained a lot of interest in the past years, however, data on the use of Er:YAG laser are scarce. The aim of this study was to compare the efficacy of Er:YAG laser and 1% topical isotretinoin in the treatment of 27 oral leukoplakia patients. Er:YAG laser (LightWalker AT, Fotona, Slovenia) was used in 27 patients with 27 leukoplakia lesions. Postoperative pain was assessed by use of visual analog scale (VAS), and the impact of laser treatment on the quality of life was assessed by the OHIP-14 questionnaire (Croatian version). Control group consisted of the same 27 patients previously treated with 1% topical isotretionin three times a day during the period of one year. No improvement in the size of leukoplakia lesions was observed after treatment with topical isotretinoin. There were significant differences between men and women according to leukoplakia localization, number of laser sessions and VAS (p<0.05). At follow-up after six months and one year, there was no recurrence of lesions. Er:YAG laser is a successful treatment for oral leukoplakia. Topical isotretionin treatment is unsuccessful in patients with oral leukoplakia.Posljednjih godina postoji veliko zanimanje za upotrebu lasera u liječenju oralne leukoplakije, ali su podatci o upotrebi Er:YAG lasera malobrojni. Cilj ovoga istraživanja bio je usporediti učinak Er:YAG lasera i 1%-tnog topikalnog izotretinoina u liječenju 27 bolesnika s oralnom leukoplakijom. Er:YAG laser (LightWalker AT, Fotona, Slovenia) je korišten u 27 bolesnika s 27 leukoplakičnih lezija. Poslijeoperacijska bol je određena uz pomoć vizualne analogne ljestvice (visual analog scale, VAS), a utjecaj na kvalitetu života mjeren je pomoću upitnika OHIP-14 (hrvatska verzija). Kontrolna skupina se sastojala od istih 27 bolesnika koji su prije toga liječeni 1%-tnim topikalnim izotretioninom tri puta na dan tijekom tri mjeseca. Nije bilo poboljšanja u veličini lezija leukoplakije nakon topikalno primijenjenog izotretinoina. Utvrđene su značajne razlike između muškaraca i žena s obzirom na lokalizaciju leukoplakije, broj laserskih zahvata i rezultata VAS (p<0,05). Šest mjeseci i godinu dana od laserskog zahvata nije bilo recidiva oralne leukoplakije. Er:YAG laser je uspješna terapija u liječenju oralne leukoplakije. Topikalna primjena izotretionina nije uspješna u liječenju oralne leukoplakije

Toward optimal implementation of cancer prevention and control programs in public health: A study protocol on mis-implementation

Abstract Background Much of the cancer burden in the USA is preventable, through application of existing knowledge. State-level funders and public health practitioners are in ideal positions to affect programs and policies related to cancer control. Mis-implementation refers to ending effective programs and policies prematurely or continuing ineffective ones. Greater attention to mis-implementation should lead to use of effective interventions and more efficient expenditure of resources, which in the long term, will lead to more positive cancer outcomes. Methods This is a three-phase study that takes a comprehensive approach, leading to the elucidation of tactics for addressing mis-implementation. Phase 1: We assess the extent to which mis-implementation is occurring among state cancer control programs in public health. This initial phase will involve a survey of 800 practitioners representing all states. The programs represented will span the full continuum of cancer control, from primary prevention to survivorship. Phase 2: Using data from phase 1 to identify organizations in which mis-implementation is particularly high or low, the team will conduct eight comparative case studies to get a richer understanding of mis-implementation and to understand contextual differences. These case studies will highlight lessons learned about mis-implementation and identify hypothesized drivers. Phase 3: Agent-based modeling will be used to identify dynamic interactions between individual capacity, organizational capacity, use of evidence, funding, and external factors driving mis-implementation. The team will then translate and disseminate findings from phases 1 to 3 to practitioners and practice-related stakeholders to support the reduction of mis-implementation. Discussion This study is innovative and significant because it will (1) be the first to refine and further develop reliable and valid measures of mis-implementation of public health programs; (2) bring together a strong, transdisciplinary team with significant expertise in practice-based research; (3) use agent-based modeling to address cancer control implementation; and (4) use a participatory, evidence-based, stakeholder-driven approach that will identify key leverage points for addressing mis-implementation among state public health programs. This research is expected to provide replicable computational simulation models that can identify leverage points and public health system dynamics to reduce mis-implementation in cancer control and may be of interest to other health areas

Identifying and Tuning the In Situ Oxygen-Rich Surface of Molybdenum Nitride Electrocatalysts for Oxygen Reduction

Rigorous in situ studies of electrocatalysts are required to enable the design of higher performing materials. Nonplatinum group metals for oxygen reduction reaction (ORR) catalysis containing light elements such as O, N, and C are known to be susceptible to both ex situ and in situ oxidation, leading to challenges associated with ex situ characterization methods. We have previously shown that the bulk O content plays an important role in the activity and selectivity of Mo–N catalysts, but further understanding of the role of composition and morphological changes at the surface is needed. Here, we report the measurement of in situ surface changes to a molybdenum nitride (MoN) thin film under ORR conditions using grazing incidence X-ray absorption and reflectivity. We show that the half-wave potential of MoN can be improved by ∼90 mV by potential conditioning up to 0.8 V versus RHE. Utilizing electrochemical analysis, dissolution monitoring, and surface-sensitive X-ray techniques, we show that under moderate polarization (0.3–0.7 V vs RHE) there is local ligand distortion, O incorporation, and amorphization of the MoN surface, without changes in roughness. Furthermore, with a controlled potential hold procedure, we show that the surface changes concurrent with potential conditioning are stable under ORR relevant potentials. Conversely, at higher potentials (≥0.8 V vs RHE), the film incorporates O, dissolves, and roughens, suggesting that in this higher potential regime, the performance enhancements are due to increased access to active sites. Density functional theory calculations and Pourbaix analysis provide insights into film stability and O incorporation as a function of potential. These findings coupled with in situ electrochemical surface-sensitive X-ray techniques demonstrate an approach to studying nontraditional surfaces in which we can leverage our understanding of surface dynamics to improve performance with the rational, in situ tuning of active sites

Nitride or Oxynitride? Elucidating the Composition–Activity Relationships in Molybdenum Nitride Electrocatalysts for the Oxygen Reduction Reaction

Molybdenum nitride (Mo−N) catalysts have shown promising activity and stability for the oxygen reduction reaction (ORR) in acid. However, the effect of oxygen (O) incorporation (from synthesis, catalysis, or exposure to air) on their activity remains elusive. Here, we use reactive sputtering to synthesize three compositions of thin-film catalysts and use extensive materials characterization to investigate the depth-dependent structure and incorporated O. We show that the as-deposited Mo−N films are highly oxidized both at the surface (>30% O) and in the bulk (3− 21% O) and that the ORR performance is strongly correlated with the bulk structure and composition. Activity for 4e− ORR is highest for compositions with the highest N/O and N/Mo ratio. Furthermore, H2O2 production for the films with moderate O content is comparable to or higher than the most H2O2-selective nonprecious metal catalysts in acidic electrolyte, on a moles per mass or surface area of catalyst basis. Density functional theory provides insight into the energetics of O incorporation and vacancy formation, and we hypothesize that activity trends with O/N ratios can be traced to the varying crystallite phases and their interactions with ORR adsorbates. This work demonstrates the prevalence and significance of O in metal nitride electrocatalysts and motivates further investigation into the role of O in other nonprecious metal materials