Molecular architectures of iron complexes for oxygen reduction catalysis-Activity enhancement by hydroxide ions coupling.

Developing cost-effective and high-performance electrocatalysts for oxygen reduction reaction (ORR) is critical for clean energy generation. Here, we propose an approach to the synthesis of iron phthalocyanine nanotubes (FePc NTs) as a highly active and selective electrocatalyst for ORR. The performance is significantly superior to FePc in randomly aggregated and molecularly dispersed states, as well as the commercial Pt/C catalyst. When FePc NTs are anchored on graphene, the resulting architecture shifts the ORR potentials above the redox potentials of Fe2+/3+ sites. This does not obey the redox-mediated mechanism operative on conventional FePc with a Fe2+-N moiety serving as the active sites. Pourbaix analysis shows that the redox of Fe2+/3+ sites couples with HO- ions transfer, forming a HO-Fe3+-N moiety serving as the ORR active sites under the turnover condition. The chemisorption of ORR intermediates is appropriately weakened on the HO-Fe3+-N moiety compared to the Fe2+-N state and thus is intrinsically more ORR active.

The relationship between the minor allele content and Alzheimer's disease.

Alzheimer's disease (AD) is a chronic neurodegenerative disease. The genetic risk factors of AD remain better understood. Using previously published dataset of common single nucleotide polymorphisms (SNPs), we studied the association between the minor allele content (MAC) in an individual and AD. We found that AD patients have higher average MAC values than matched controls. We identified a risk prediction model that could predict 2.19% of AD cases. We also identified 49 genes whose expression levels correlated with both MAC and AD. By pathway and process enrichment analyses, these genes were found in pathways or processes closely related to AD. Our study suggests that AD may be linked with too many genetic variations over a threshold. The method of correlations with both MAC and traits appears to be effective in high efficiency identification of target genes for complex traits.

Collective effects of SNPs on transgenerational inheritance in Caenorhabditis elegans and budding yeast.

We studied the collective effects of single nucleotide polymorphisms (SNPs) on transgenerational inheritance in Caenorhabditis elegans recombinant inbred advanced intercross lines (RIAILs) and yeast segregants. We divided the RIAILs and segregants into two groups of high and low minor allele content (MAC). RIAILs with higher MAC needed less generations of benzaldehyde training to gain a stable olfactory imprint and showed a greater change from normal after benzaldehyde training. Yeast segregants with higher MAC showed a more dramatic shortening of the lag phase length after ethanol exposure. The short lag phase as acquired by ethanol training was more dramatically lost after recovery in ethanol free medium for the high MAC group. We also found a preferential association between MAC and traits linked with higher number of additive QTLs. These results suggest a role for the collective effects of SNPs in transgenerational inheritance, and may help explain human variations in disease susceptibility.

Collective effects in a diffraction-limited storage ring.

This paper gives an overview of collective effects that are likely to appear and possibly limit the performance in a diffraction-limited storage ring (DLSR) that stores a high-intensity ultra-low-emittance beam. Beam instabilities and other intensity-dependent effects that may significantly impact the machine performance are covered. The latter include beam-induced machine heating, Touschek scattering, intra-beam scattering, as well as incoherent tune shifts. The general trend that the efforts to achieve ultra-low emittance result in increasing the machine coupling impedance and the beam sensitivity to instability is reviewed. The nature of coupling impedance in a DLSR is described, followed by a series of potentially dangerous beam instabilities driven by the former, such as resistive-wall, TMCI (transverse mode coupling instability), head-tail and microwave instabilities. In addition, beam-ion and CSR (coherent synchrotron radiation) instabilities are also treated. Means to fight against collective effects such as lengthening of the bunch with passive harmonic cavities and bunch-by-bunch transverse feedback are introduced. Numerical codes developed and used to evaluate the machine coupling impedance, as well as to simulate beam instability using the former as inputs are described.

Screening and collective effects in randomly pinned fluids: a new theoretical framework.

We propose a theoretical framework for the dynamics of bulk isotropic hard-sphere systems in the presence of randomly pinned particles and apply this theory to supercooled water to validate it. Structural relaxation is mainly governed by local and non-local activated process. As the pinned fraction grows, a local caging constraint becomes stronger and the long range collective aspect of relaxation is screened by immobile obstacles. Different responses of the local and cooperative motions results in subtle predictions for how the alpha relaxation time varies with pinning and density. Our theoretical analysis for the relaxation time of water with pinned molecules quantitatively well describe previous simulations. In addition, the thermal dependence of relaxation for unpinned bulk water is also consistent with prior computational and experimental data.

Phononic Cavity Optomechanics of Atomically Thin Crystal in Plasmonic Nanocavity.

In the picture of molecular cavity optomechanics, surface-enhanced Raman scattering (SERS) can be understood as molecular oscillators parametrically coupled to plasmonic nanocavities supporting an extremely localized optical field. This enables SERS from conventional fingerprint detection toward quantum nanotechnologies associated with, e.g., frequency upconversion and optomechanically induced transparency. Here, we study a phononic cavity optomechanical system consisting of a monolayer MoS2 placed inside a plasmonic nanogap, where the coherent phonon-plasmon interaction involves the collective oscillation from tens of thousands of unit cells of the MoS2 crystal. We observe the selective nonlinear SERS enhancement of the system as determined by the laser-plasmon detuning, suggesting the dynamic backaction modification of the phonon populations. Anomalous superlinear power dependence of a second-order Raman-inactive phonon mode with respect to the first-order phonons is also observed, indicating the distinctive properties of the phononic nanodevice compared with the molecular system. Our results promote the development of robust phononic optomechanical nanocavities to further explore the related quantum correlation and nonlinear effects including parametric instabilities.

Decomposition of socioeconomic inequalities in arboviral diseases in Brazil and Colombia (2007-2017).

BACKGROUND: We used surveillance data from Brazil and Colombia during 2007-2017 to assess the presence of socioeconomic inequalities on dengue, chikungunya and Zika at the neighborhood level in two Latin American cities. METHODS: To quantify the inequality, we estimated and decomposed the relative concentration index of inequality (RCI) accounting for the spatiotemporal distribution of the diseases. RESULTS: There were 281 426 arboviral cases notified in Fortaleza, Brazil, and 40 889 in Medellin, Colombia. The RCI indicated greater concentration of dengue cases among people living in low socioeconomic settings in both sites. The RCIs for chikungunya in Fortaleza covered the line of equality during their introduction in 2014, while the RCIs for Zika and chikungunya in Medellin indicated the presence of a small inequality. The RCI decomposition showed that year of notification and age were the main contributors to this inequality. In Medellin, the RCI decomposition showed that age and access to waste management accounted for 75.5%, 72.2% and 54.5% of the overall inequality towards the poor for dengue, chikungunya and Zika, respectively. CONCLUSIONS: Our study presents estimates of the socioeconomic inequality of arboviruses and its decomposition in two Latin American cities. We corroborate the concentration of arboviral diseases in low socioeconomic neighborhoods and identify that year of occurrence, age, presence of healthcare facilities and waste management are key determinants of the heterogenous distribution of endemic arboviruses across the socioeconomic spectrum.

Self-generated oxygen gradients control collective aggregation of photosynthetic microbes.

For billions of years, photosynthetic microbes have evolved under the variable exposure to sunlight in diverse ecosystems and microhabitats all over our planet. Their abilities to dynamically respond to alterations of the luminous intensity, including phototaxis, surface association and diurnal cell cycles, are pivotal for their survival. If these strategies fail in the absence of light, the microbes can still sustain essential metabolic functionalities and motility by switching their energy production from photosynthesis to oxygen respiration. For suspensions of motile C. reinhardtii cells above a critical density, we demonstrate that this switch reversibly controls collective microbial aggregation. Aerobic respiration dominates over photosynthesis in conditions of low light, which causes the microbial motility to sensitively depend on the local availability of oxygen. For dense microbial populations in self-generated oxygen gradients, microfluidic experiments and continuum theory based on a reaction-diffusion mechanism show that oxygen-regulated motility enables the collective emergence of highly localized regions of high and low cell densities.

Comparative effects of different antibiotics on antibiotic resistance during swine manure composting.

This study explored commonly-used antibiotics (lincomycin, chlorotetracycline, sulfamethoxazole, and ciprofloxacin) and their collective effects on antibiotic resistance during composting. In the first 7 days, ciprofloxacin showed the greatest influence on the physicochemical factors among the studied antibiotics; the removal of antibiotic resistance genes (ARGs) in the multiple-antibiotic treatment was significantly less than single-antibiotic treatments; especially, the largest removal of ribosomal protection genes (tetW and tetO) occurred in single ciprofloxacin treatment. In the end of composting, similar removal ratio (29.71-99.79%) of ARGs was achieved in different treatments (p greater than 0.05); Chloroflexi became the main phylum and it was closely associated with ARGs removal based on the network analysis. Potential host bacteria of ARGs varied with different antibiotics; in particular, the presence of multiple antibiotics increased potential host bacteria of ermA, sul1 and tetO. Above all, collective effects of different antibiotics led to the enrichment of antibiotic resistance in the composting.

Competitividad de los gobiernos subnacionales y su relación con la mortalidad por COVID-19 en Perú / Competitiveness of subnational governments and their relationship with COVID-19 mortality in Peru

Introducción: La pandemia por COVID-19 ha puesto de manifiesto las grandes desigualdades en la población mundial. Objetivo: Describir la correlación entre la competitividad y la mortalidad por COVID-19 en el Perú, teniendo como elemento de estudio a los gobiernos subnacionales. Material y Métodos: Estudio observacional basado en el análisis secundario de las muertes por COVID-19 en el 2020 y el índice de competitividad regional de los gobiernos subnacionales 2019. Se calcularon: tasas bruta y estandarizada, índice de efecto y de desigualdad de la pendiente, diferencia y razón de tasas brutas y estandarizadas, riesgo atribuible poblacional, gradiente social, así como brechas relativas y absolutas de mortalidad por COVID-19. Resultados: En el año 2020, la tasa estandarizada de mortalidad por COVID-19 (TEM-COVID-19) fue 267,61 muertes x 105 habitantes. El 21,53 por ciento de la varianza de la TEM-COVID-19 es explicada por el índice de competitividad regional del año 2019 (p= 0,019); el índice de desigualdad de la pendiente fue 29,68 y, por cada punto en el INCORE 2019, la TEM-COVID-19 aumentó 100,78 puntos (R2a= 0,181). En el quintil 1 de competitividad regional, esta fue 151,83, mientras que en el quintil 5 llegó a 449,15. La brecha de desigualdad absoluta entre ambos quintiles fue 297,32 y alcanzó 2,95 en la brecha de desigualdad relativa. La curva de concentración evidenció la desigualdad socio geográfica de las muertes por COVID-19 en el año 2020. Conclusiones: La mortalidad por COVID-19 se incrementó a medida que aumentaba la competitividad de los gobiernos subnacionales evidenciando la desigualdad socio-geográfica del impacto de la pandemia(AU)

Introduction: The COVID-19 pandemic has revealed high disparities in the world population. Objective: To describe the correlation between competitiveness and mortality from COVID-19 in Peru, with subnational governments as an element of study. Material and Methods: Observational study based on the secondary analysis of deaths from COVID-19 that occurred in 2020 and the regional competitiveness index of subnational governments in 2019. The crude and standardized rates, the effect index, the difference and ratio of crude and standardized rates, the population attributable risk, the inequality gradient, and the relative and absolute gaps in mortality from COVID-19 were calculated. Results: In 2020, the standardized mortality rate for COVID-19 (COVID-19-SMR) was 267,61 deaths per 105 inhabitants. Additionally, 21,53 percent of the variance from the COVID-19-SMR is explained by the regional competitiveness index 2019 (p= 0,019); the slope inequality index was 29,68 and, for each point in the INCORE 2019, the COVID-19-SMR increased 100,78 points (R2a= 0,181). In quintile 1 of regional competitiveness, it was 151,83, while in quintile 5 it reached 449,15. The absolute inequality gap between both quintiles was 297,32 and it reached 2,95 in the relative inequality gap. The concentration curve evidenced the socio-geographic inequality of deaths from COVID-19 in 2020. Conclusions: Mortality increased as subnational governments became more competitive, evidencing the socio-geographical inequality of the impact of the COVID-19 pandemic(AU)

Características de la población afectada por COVID-19 en un centro de salud urbano de Zaragoza / Characteristics of the population affected by COVID-19 at an urban Primary Care Centre in Zaragoza

Objetivo: analizar las características sociodemográficas de la población urbana de Zaragoza afectada por COVID-19. Objetivos específicos: describir dicha población según edad, sexo, origen, nivel socioeconómico y destino tras la consulta; describir las características de los contagios por COVID-19; y analizar la asociación entre el origen de la población, el nivel socioeconómico y el contagio por contacto estrecho. Método: estudio descriptivo transversal con los casos contagiados de COVID-19 entre febrero y septiembre de 2020 de un centro de salud urbano en Zaragoza, España (N= 1.277). Los datos se obtuvieron de la base de datos de Atención Primaria, las bases públicas de Aragón, del Servicio de Vigilancia en Salud Pública y de las encuestas epidemiológicas de rastreo. Se realizaron pruebas de Chi cuadrado con una significación estadística p< 0,05. Resultados: se incluyeron 1.277 casos (100%). El 54,74% era mujer con una mediana de edad de 39 años, el 62,02% era población extranjera, el 62,96% tenía una renta inferior a 18.000 € anuales y el 91,3% volvió al domicilio tras la consulta. Un 67,80% tuvo un contacto con una persona contagiada principalmente en el domicilio (62,63%). Se halló asociación entre el origen de la población y el nivel de renta, siendo inferior en las personas extranjeras (p< 0,001), quienes tuvieron además más contagios por contacto estrecho (p= 0,009), especialmente en el ámbito domiciliar frente al social de la población autóctona (p= 0,039). Conclusiones: la pandemia por COVID-19 afecta de manera más acusada a las poblaciones vulnerables, especialmente a la población extranjera con menos recursos. Se deben impulsar estrategias de educación de salud adaptadas a la comunidad.(AU)

Objective: to analyse the sociodemographic characteristics of the urban population of Zaragoza affected by COVID-19. Specific objectives: to describe said population according to age, gender, origin, socioeconomic level, and destination after consultation; to describe the characteristics of COVID-19 contagions; and to analyse the association between the origin of the population, their socioeconomic level, and infection by close contact. Method: a cross-sectional study with the cases of COVID-19 contagion between February and September 2020, from an urban Primary Care Centre in Zaragoza, (N= 1,277). Data were retrieved from the Primary Care database, the public bases from Aragon, the Public Health Surveillance Service, and the epidemiological screening surveys. Square Chi tests were conducted, and statistical significance was p< 0.05. Results: the study included 1,277 cases (100%); 54.74% were female with a median age of 39 years, 62.02% were of foreign origin, 62.96% had an income <18,000 euros per year, and 91.3% went back home after the consultation. 67.80% of them had contact with an infected person, mainly at home (62.63%). An association was found between the origin of the population and their income level, which was lower for foreigners (p< 0.001), who also presented a higher number of contagions due to close contact (p= 0.009), particularly in the home setting vs. the social setting for the native population (p= 0.039). Conclusions: the COVID-19 pandemic had a higher impact on vulnerable populations, particularly the foreign population with lower income. Health education strategies must be promoted, which are adapted to the community.(AU)

Análise microbiológica da água em escolas públicas de Marabá, Pará / Microbiological analysis of water in public schools in Marabá, Pará

Objetivo: analisar a qualidade microbiológica da água de cinco escolas públicas da cidade de Marabá-PA e correlacionar com possíveis fatores de desigualdades sociais em saúde no entorno dessas escolas. Metodologia: as análises microbiológicas foram realizadas em cinco escolas públicas no interior do Pará, usando a técnica do número mais provável, associado a registro das características do entorno das escolas. O teste T Student foi utilizado para verificar as diferenças entre os resultados microbiológicos da água entre as escolas em que houve contaminação e também para testar as diferenças entre a vulnerabilidade socioambiental urbana no entorno das escolas e a contaminação da água. Resultados: observaram-se diferenças estatisticamente significantes entre as escolas E3 e E5 no teste para coliformes totais (p=0,043) e termotolerantes (p=0,008). A partir das condições de vulnerabilidade socioambiental urbana no entorno a escolas, encontrou-se diferenças estatisticamente significativas entre as escolas apenas em relação às condições de saneamento (p=0,05). Considerações Finais: as condições microbiológicas da água utilizada em duas escolas são insatisfatórias, o que indica risco à saúde para alunos, professores e funcionários das escolas.

Objective: to analyze the microbiological quality of water in five public schools in the city of Marabá-PA and to correlate with possible factors of social inequalities in health around these schools. Methodology: the analysis of the microbiological water quality was carried out in five schools in the interior of Pará, using the most likely number technique, associated with recording the characteristics of the schools' surroundings. We used Student T test to verify the differences between the microbiological results of water between the schools where there was contamination and to test the differences between the urban socio-environmental vulnerability around the schools and the water contamination. Results: statistically significant differences were observed between schools E3 and E5 in the test for total coliforms (p=0.043) and thermotolerants (p=0.008). We found statistically significant differences were found between schools only in relation to sanitation conditions (p=0.05). Final Considerations: the microbiological conditions of the water used in two schools are unsatisfactory, which indicates a health risk for students, teachers and school team.