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1.
Siglo cero (Madr.) ; 54(4): 29-48, oct.-dic. 2024.
Artigo em Espanhol | IBECS | ID: ibc-229227

RESUMO

Esta investigación busca profundizar en la segregación escolar del alumnado con necesidades educativas especiales del segundo ciclo de Educación Infantil estimando su magnitud, determinando la incidencia de la titularidad del centro y de su adscripción al Programa Bilingüe y describiendo su evolución. Para ello, se realiza un estudio ex post facto con datos de los 10.182 estudiantes del segundo ciclo de Educación Infantil matriculados en alguno de los 77 centros ordinarios públicos y privados-concertados situados en dos ciudades de tamaño medio-grande de la Comunidad de Madrid. Los resultados indican que la magnitud de la segregación escolar está en torno al 0.20 (ISG); que la incidencia de la titularidad es baja (4.6 %), pero es alta la del Programa Bilingüe (17.2 % de promedio); y que la segregación ha descendido ligeramente en los últimos años, pero las diferencias entre centros atendiendo a su titularidad y adscripción al Programa Bilingüe han crecido. Con ello, se concluye que hay que prestar atención a la segregación en Educación Infantil y tomar medidas para combatirla. También se destaca la necesidad de replantear el Programa Bilingüe por su incidencia en la segregación escolar. (AU)


This research aims to explore the school segregation of students with special educational needs in the second cycle of Early Childhood Education by estimating its magnitude, determining the incidence of school ownership and affiliation to the Bilingual Program, and describing its evolution. To achieve this, we conduct an ex post facto study with data from the 10,182 students enrolled in one of the 77 public and private-subsidised schools in the Community of Madrid. The results indicate that the magnitude of school segregation is around 0.20 (ISG); that the incidence of school ownership is low (4.6 %), while the incidence of the Bilingual Program is high (17.2 % on average); and that segregation has slightly decreased in recent years, however the differences between schools based on ownership and affiliation to the Bilingual Program have increased. Therefore, we conclude that it is necessary to address segregation in Early Childhood Education and that measures need to be taken to combat it. We also highlight the importance of reconsidering the Bilingual Program due to its impact on school segregation. (AU)


Assuntos
Humanos , Pré-Escolar , Criança , Deficiências da Aprendizagem , Educação/estatística & dados numéricos
2.
Siglo cero (Madr.) ; 54(4): 29-48, oct.-dic. 2024.
Artigo em Espanhol | IBECS | ID: ibc-EMG-557

RESUMO

Esta investigación busca profundizar en la segregación escolar del alumnado con necesidades educativas especiales del segundo ciclo de Educación Infantil estimando su magnitud, determinando la incidencia de la titularidad del centro y de su adscripción al Programa Bilingüe y describiendo su evolución. Para ello, se realiza un estudio ex post facto con datos de los 10.182 estudiantes del segundo ciclo de Educación Infantil matriculados en alguno de los 77 centros ordinarios públicos y privados-concertados situados en dos ciudades de tamaño medio-grande de la Comunidad de Madrid. Los resultados indican que la magnitud de la segregación escolar está en torno al 0.20 (ISG); que la incidencia de la titularidad es baja (4.6 %), pero es alta la del Programa Bilingüe (17.2 % de promedio); y que la segregación ha descendido ligeramente en los últimos años, pero las diferencias entre centros atendiendo a su titularidad y adscripción al Programa Bilingüe han crecido. Con ello, se concluye que hay que prestar atención a la segregación en Educación Infantil y tomar medidas para combatirla. También se destaca la necesidad de replantear el Programa Bilingüe por su incidencia en la segregación escolar. (AU)


This research aims to explore the school segregation of students with special educational needs in the second cycle of Early Childhood Education by estimating its magnitude, determining the incidence of school ownership and affiliation to the Bilingual Program, and describing its evolution. To achieve this, we conduct an ex post facto study with data from the 10,182 students enrolled in one of the 77 public and private-subsidised schools in the Community of Madrid. The results indicate that the magnitude of school segregation is around 0.20 (ISG); that the incidence of school ownership is low (4.6 %), while the incidence of the Bilingual Program is high (17.2 % on average); and that segregation has slightly decreased in recent years, however the differences between schools based on ownership and affiliation to the Bilingual Program have increased. Therefore, we conclude that it is necessary to address segregation in Early Childhood Education and that measures need to be taken to combat it. We also highlight the importance of reconsidering the Bilingual Program due to its impact on school segregation. (AU)


Assuntos
Humanos , Pré-Escolar , Criança , Deficiências da Aprendizagem , Educação/estatística & dados numéricos
3.
Prog Neurobiol ; 240: 102655, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38969016

RESUMO

Object recognition often involves the brain segregating objects from their surroundings. Neurophysiological studies of figure-ground texture segregation have yielded inconsistent results, particularly on whether V1 neurons can perform figure-ground texture segregation or just detect texture borders. To address this issue from a population perspective, we utilized two-photon calcium imaging to simultaneously record the responses of large samples of V1 and V4 neurons to figure-ground texture stimuli in awake, fixating macaques. The average response changes indicate that V1 neurons mainly detect texture borders, while V4 neurons are involved in figure-ground segregation. However, population analysis (SVM decoding of PCA-transformed neuronal responses) reveal that V1 neurons not only detect figure-ground borders, but also contribute to figure-ground texture segregation, although requiring substantially more principal components than V4 neurons to reach a 75 % decoding accuracy. Individually, V1/V4 neurons showing larger (negative/positive) figure-ground response differences contribute more to figure-ground segregation. But for V1 neurons, the contribution becomes significant only when many principal components are considered. We conclude that V1 neurons participate in figure-ground segregation primarily by defining the figure borders, and the poorly structured figure-ground information V1 neurons carry could be further utilized by V4 neurons to accomplish figure-ground segregation.

4.
Sci Rep ; 14(1): 15713, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977811

RESUMO

Matching of various chalcogenide films shows the advantage of delivering multilayer heterostructures whose physical properties can be tuned with respect to the ones of the constituent single films. In this work, (Ge-Sb-Te)-based heterostructures were deposited by radio frequency sputtering on Si(100) substrates and annealed up to 400 °C. The as-deposited and annealed samples were studied by means of X-ray fluorescence, X-ray diffraction, scanning transmission electron microscopy, electron energy loss spectroscopy and Raman spectroscopy. The heterostructures, combining thermally stable thin layers (i. e. Ge-rich Ge5.5Sb2Te5, Ge) and films exhibiting fast switching dynamics (i. e. Sb2Te3), show, on the one side, higher crystallization-onset temperatures than the standard Ge2Sb2Te5 alloy and, on the other side, none to minimal Ge-segregation.

5.
medRxiv ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38947046

RESUMO

IMPORTANCE: Disparities in cognition, including dementia occurrence, persist between White and Black older adults, and are possibly influenced by early educational differences stemming from structural racism. However, the relationship between school racial segregation and later-life cognition remains underexplored. OBJECTIVE: To investigate the association between childhood contextual exposure to school racial segregation and cognitive outcomes in later life. DESIGN SETTING AND PARTICIPANTS: Data from 16,625 non-Hispanic White (hereafter, White) and 3,335 non-Hispanic Black (hereafter, Black) Americans aged 65 or older were analyzed from the Health and Retirement Study. EXPOSURES: State-level White-Black dissimilarity index for public elementary schools in the late 1960s (range: 0-100) was used to measure school segregation. States were categorized into high segregation (383.6) and low segregation (<83.6) based on the top quintile. MAIN OUTCOMES AND MEASURES: Cognitive scores, cognitive impairment (with or without dementia), and dementia were assessed using the Telephone Interview for Cognitive Status (TICS) and proxy assessment. Multilevel regression analyses were conducted, adjusting for demographic covariates, socioeconomic status, and health factors. Stratified analyses by race were performed. RESULTS: The mean (SD) age of participants was 78.5 (5.7) years, and 11,208 (56.2%) were female. Participants exposed to high segregation exhibited lower cognitive scores (12.6 vs. 13.6; P<0.001) and higher prevalence of cognitive impairment (50.8% vs 41.4%; P<0.001) and dementia (26.0% vs. 19.5%; P<0.001), compared to those with low segregation exposure. Multilevel analyses revealed a significant negative association between school segregation and later-life cognitive even after adjusting sequentially for potential confounders, and these associations were stronger among Black than White participants. Notably, in the fully adjusted model, Black participants exposed to high segregation displayed significantly lower cognitive scores (-0.51; 95% CI: -0.94, -0.09) and higher likelihood of cognitive impairment (adjusted Odds Ratio [aOR]: 1.45, 95% CI: 1.22, 1.72) and dementia (aOR: 1.31, 95% CI: 1.06, 1.63). CONCLUSIONS AND RELEVANCE: Our study underscores that childhood exposure to state-level school segregation is associated with late-life cognition, especially for Black Americans. Given the rising trend of school segregation in the US, educational policies aimed at reducing segregation are crucial to address health inequities. Clinicians can leverage patients' early-life educational circumstances to promote screening, prevention, and management of cognitive disorders.

6.
Proc Natl Acad Sci U S A ; 121(28): e2401661121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38950373

RESUMO

In US cities, neighborhoods have long been racially segregated. However, people do not spend all their time in their neighborhoods, and the consequences of residential segregation may be tempered by the contact people have with other racial groups as they traverse the city daily. We examine the extent to which people's regular travel throughout the city is to places "beyond their comfort zone" (BCZ), i.e., to neighborhoods of racial composition different from their own-and why. Based on travel patterns observed in more than 7.2 million devices in the 100 largest US cities, we find that the average trip is to a neighborhood less than half as racially different from the home neighborhood as it could have been given the city. Travel to grocery stores is least likely to be BCZ; travel to gyms and parks, most likely; however, differences are greatest across cities. For the first ~10 km people travel from home, neighborhoods become increasingly more BCZ for every km traveled; beyond that point, whether neighborhoods do so depends strongly on the city. Patterns are substantively similar before and after COVID-19. Our findings suggest that policies encouraging more 15-min travel-that is, to amenities closer to the home-may inadvertently discourage BCZ movement. In addition, promoting use of certain "third places" such as restaurants, bars, and gyms, may help temper the effects of residential segregation, though how much it might do so depends on city-specific conditions.


Assuntos
COVID-19 , Características de Residência , Humanos , COVID-19/epidemiologia , Características da Vizinhança , Cidades , Viagem/estatística & dados numéricos , Estados Unidos , Segregação Social , SARS-CoV-2 , Grupos Raciais/estatística & dados numéricos
7.
Soc Sci Res ; 121: 103025, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38871434

RESUMO

Today, black-owned banks are important financial resources challenging economic exclusion. Nevertheless, they do not associate strongly with building black wealth. Some scholars argue this signals black-owned banks are ornamental, or ineffective responses to legacies of economic exclusion in black segregated neighborhoods. To engage these critiques, I draw on the dialectical theoretical frames of cultural assets and structural deficits to examine the effectiveness of black-owned banks during the subprime lending boom-a period when bank practices exploiting a history of economic exclusion in black segregated neighborhoods intensify. Specifically, I analyze administrative data from the Federal Deposit Insurance Corporation (FDIC) and the Home Mortgage Disclosure Act (HMDA) to assess whether black-owned banks associate with access to mortgage credit when the subprime lending boom peaks in 2006. Using propensity score matching with inverse probability weighting, I find black-owned banks do not associate with mortgage originations in 2006; but neighborhoods with black-owned banks receive fewer subprime mortgage loans, compared to matched ones without them. As such, black-owned banks appear to effectively shield black segregated neighborhoods from the time period's predation. Overall, findings imply black-owned banks support protective credit markets during periods of intensifying economic exclusion and exploitation.

8.
Spat Spatiotemporal Epidemiol ; 49: 100652, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38876565

RESUMO

Racialized economic segregation, a key metric that simultaneously accounts for spatial, social and income polarization in communities, has been linked to adverse health outcomes, including morbidity and mortality. Due to the spatial nature of this metric, the association between health outcomes and racialized economic segregation could also change with space. Most studies assessing the relationship between racialized economic segregation and health outcomes have always treated racialized economic segregation as a fixed effect and ignored the spatial nature of it. This paper proposes a two-stage Bayesian statistical framework that provides a broad, flexible approach to studying the spatially varying association between premature mortality and racialized economic segregation while accounting for neighborhood-level latent health factors across US counties. The two-stage framework reduces the dimensionality of spatially correlated data and highlights the importance of accounting for spatial autocorrelation in racialized economic segregation measures, in health equity focused settings.


Assuntos
Teorema de Bayes , Mortalidade Prematura , Segregação Social , Humanos , Estados Unidos/epidemiologia , Análise Espacial , Masculino , Feminino , Características de Residência/estatística & dados numéricos
9.
BMC Med ; 22(1): 249, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38886716

RESUMO

BACKGROUND: Residing in a disadvantaged neighborhood has been linked to increased mortality. However, the impact of residential segregation and social vulnerability on cause-specific mortality is understudied. Additionally, the circulating metabolic correlates of neighborhood sociodemographic environment remain unexplored. Therefore, we examined multiple neighborhood sociodemographic metrics, i.e., neighborhood deprivation index (NDI), residential segregation index (RSI), and social vulnerability index (SVI), with all-cause and cardiovascular disease (CVD) and cancer-specific mortality and circulating metabolites in the Southern Community Cohort Study (SCCS). METHODS: The SCCS is a prospective cohort of primarily low-income adults aged 40-79, enrolled from the southeastern United States during 2002-2009. This analysis included self-reported Black/African American or non-Hispanic White participants and excluded those who died or were lost to follow-up ≤ 1 year. Untargeted metabolite profiling was performed using baseline plasma samples in a subset of SCCS participants. RESULTS: Among 79,631 participants, 23,356 deaths (7214 from CVD and 5394 from cancer) were documented over a median 15-year follow-up. Higher NDI, RSI, and SVI were associated with increased all-cause, CVD, and cancer mortality, independent of standard clinical and sociodemographic risk factors and consistent between racial groups (standardized HRs among all participants were 1.07 to 1.20 in age/sex/race-adjusted model and 1.04 to 1.08 after comprehensive adjustment; all P < 0.05/3 except for cancer mortality after comprehensive adjustment). The standard risk factors explained < 40% of the variations in NDI/RSI/SVI and mediated < 70% of their associations with mortality. Among 1110 circulating metabolites measured in 1688 participants, 134 and 27 metabolites were associated with NDI and RSI (all FDR < 0.05) and mediated 61.7% and 21.2% of the NDI/RSI-mortality association, respectively. Adding those metabolites to standard risk factors increased the mediation proportion from 38.4 to 87.9% and 25.8 to 42.6% for the NDI/RSI-mortality association, respectively. CONCLUSIONS: Among low-income Black/African American adults and non-Hispanic White adults living in the southeastern United States, a disadvantaged neighborhood sociodemographic environment was associated with increased all-cause and CVD and cancer-specific mortality beyond standard risk factors. Circulating metabolites may unveil biological pathways underlying the health effect of neighborhood sociodemographic environment. More public health efforts should be devoted to reducing neighborhood environment-related health disparities, especially for low-income individuals.


Assuntos
População Branca , Humanos , Sudeste dos Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Masculino , Feminino , Idoso , Adulto , Estudos Prospectivos , População Branca/estatística & dados numéricos , Doenças Cardiovasculares/mortalidade , Características de Residência , Neoplasias/mortalidade , Neoplasias/sangue , Negro ou Afro-Americano/estatística & dados numéricos , Características da Vizinhança , Pobreza , Mortalidade/tendências , Fatores Socioeconômicos
10.
ACS Appl Mater Interfaces ; 16(26): 33360-33370, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38888395

RESUMO

The large open circuit voltage (VOC) loss and phase segregation are two main obstacles hindering the development of wide-bandgap perovskite solar cells (PSCs). Even though substantial progress has been made through crystallization regulation and surface modification on perovskite, the mechanism of VOC loss and phase segregation has rarely been studied. In this paper, we first investigate the halide ions distribution along the out-of-plane direction and find the initial inhomogeneous distribution of halide ions during the crystallization process is an important reason. It leads to the formation of an unfavorable potential well in PSCs, resulting in VOC loss as well as generation of strong strain exacerbating phase segregation. Through introducing melatonin (MT) into perovskite precursors, a homogeneous distribution of halide anions is realized due to the well-regulated crystallization. Consequently, the treated PSCs exhibit an optimized power conversion efficiency (PCE) of 22.88% with a VOC loss as low as 0.38 V, which are the best values for wide-bandgap PSCs up to now.

11.
Materials (Basel) ; 17(11)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38893986

RESUMO

Secondary cooling electromagnetic stirring (S-EMS) significantly impacts the internal quality of continuous casting slabs. In order to investigate the effects of S-EMS modes on segregation in slabs, a three-dimensional numerical model of the full-scale flow field, solidification, and mass transfer was established. A comparative analysis was conducted between continuous electromagnetic stirring and alternate stirring modes regarding their impacts on steel flow, solidification, and carbon segregation. The results indicated that adopting the alternate stirring mode was more advantageous for achieving uniform flow fields and reducing the disparity in solidification endpoints, thus mitigating carbon segregation. Specifically, the central carbon segregation index under continuous stirring at 320 A was 1.236, with an average of 1.247, while under alternate stirring, the central carbon segregation index decreased to 1.222 with an average of 1.227.

12.
Eur J Cell Biol ; 103(3): 151430, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38897036

RESUMO

Chaperonin Containing Tailless complex polypeptide 1 (CCT) is a molecular chaperone composed of eight distinct subunits that can exist as individual monomers or as components of a double oligomeric ring, which is essential for the folding of actin and tubulin and other substrates. Here we assess the role of CCT subunits in the context of cell cycle progression by individual subunit depletions upon siRNA treatment in mammalian cells. The depletion of individual CCT subunits leads to variation in the distribution of cell cycle phases and changes in mitotic index. Mitotic defects, such as unaligned chromosomes occur when CCTδ is depleted, concurrent with a reduction in spindle pole-localised p150Glued, a component of the dynactin complex and a binding partner of monomeric CCTδ. In CCTδ-depleted cells, changes in the elution profile of p150Glued are observed consistent with altered conformations and or assembly states with the dynactin complex. Addition of monomeric CCTδ, in the form of GFP-CCTδ, restores correct p150Glued localisation to the spindle poles and rescues the mitotic segregation defects that occur when CCTδ is depleted. This study demonstrates a requirement for CCTδ in its monomeric form for correct chromosome segregation via a mechanism that promotes the correct localisation of p150Glued, thus revealing further complexities to the interplay between CCT, tubulin folding and microtubule dynamics.

13.
J Urban Health ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926219

RESUMO

Racial residential segregation has been deemed a fundamental cause of health inequities. It is a result of historical and contemporary policies such as redlining that have created a geographic separation of races and corresponds with an inequitable distribution of health-promoting resources. Redlining and racial residential segregation may have contributed to racial inequities in COVID-19 vaccine administration in the early stages of public accessibility. We use data from the National Archives (historical redlining), Home Mortgage Disclosure Act (contemporary redlining), American Community Survey from 1940 (historical racial residential segregation) and 2015-2019 (contemporary racial residential segregation), and Washington D.C. government (COVID-19 vaccination administration) to assess the relationships between redlining, racial residential segregation, and COVID-19 vaccine administration during the early stages of vaccine distribution when a tiered system was in place due to limited supply. Pearson correlation was used to assess whether redlining and racial segregation, measured both historically and contemporarily, were correlated with each other in Washington D.C. Subsequently, linear regression was used to assess whether each of these measures associate with COVID-19 vaccine administration. In both historical and contemporary analyses, there was a positive correlation between redlining and racial residential segregation. Further, redlining and racial residential segregation were each positively associated with administration of the novel COVID-19 vaccine. This study highlights the ongoing ways in which redlining and segregation contribute to racial health inequities. Eliminating racial health inequities in American society requires addressing the root causes that affect access to health-promoting resources.

14.
bioRxiv ; 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38903120

RESUMO

During meiosis, homologous chromosomes segregate so that alleles are transmitted equally to haploid gametes, following Mendel's Law of Segregation. However, some selfish genetic elements drive in meiosis to distort the transmission ratio and increase their representation in gametes. The established paradigms for drive are fundamentally different for female vs male meiosis. In male meiosis, selfish elements typically kill gametes that do not contain them. In female meiosis, killing is predetermined, and selfish elements bias their segregation to the single surviving gamete (i.e., the egg in animal meiosis). Here we show that a selfish element on mouse chromosome 2, R2d2, drives using a hybrid mechanism in female meiosis, incorporating elements of both male and female drivers. If R2d2 is destined for the polar body, it manipulates segregation to sabotage the egg by causing aneuploidy that is subsequently lethal in the embryo, so that surviving progeny preferentially contain R2d2. In heterozygous females, R2d2 orients randomly on the metaphase spindle but lags during anaphase and preferentially remains in the egg, regardless of its initial orientation. Thus, the egg genotype is either euploid with R2d2 or aneuploid with both homologs of chromosome 2, with only the former generating viable embryos. Consistent with this model, R2d2 heterozygous females produce eggs with increased aneuploidy for chromosome 2, increased embryonic lethality, and increased transmission of R2d2. In contrast to a male meiotic driver, which kills its sister gametes produced as daughter cells in the same meiosis, R2d2 eliminates "cousins" produced from meioses in which it should have been excluded from the egg.

15.
Sci Rep ; 14(1): 14481, 2024 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-38914600

RESUMO

Haploid induction (HI) holds great promise in expediting the breeding process in onion, a biennial cross-pollinated crop. We used the CENH3-based genome elimination technique in producing a HI line in onion. Here, we downregulated AcCENH3 using the RNAi approach without complementation in five independent lines. Out of five events, only three could produce seeds upon selfing. The progenies showed poor seed set and segregation distortion, and we were unable to recover homozygous knockdown lines. The knockdown lines showed a decrease in accumulation of AcCENH3 transcript and protein in leaf tissue. The decrease in protein content in transgenic plants was correlated with poor seed set. When the heterozygous knockdown lines were crossed with wild-type plants, progenies showed HI by genome elimination of the parental chromosomes from AcCENH3 knockdown lines. The HI efficiency observed was between 0 and 4.63% in the three events, and it was the highest (4.63%) when E1 line was crossed with wildtype. Given the importance of doubled haploids in breeding programmes, the findings from our study are poised to significantly impact onion breeding.


Assuntos
Regulação da Expressão Gênica de Plantas , Haploidia , Cebolas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Interferência de RNA , Cebolas/genética , Cebolas/metabolismo , Plantas Geneticamente Modificadas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação para Baixo , Melhoramento Vegetal/métodos , Técnicas de Silenciamento de Genes
16.
Nanomaterials (Basel) ; 14(12)2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38921869

RESUMO

Shear banding is much dependent on the glass-glass interfaces (GGIs) in metallic nanoglasses (NGs). Nevertheless, the current understanding of the glass phase of GGIs is not well established for controlling the shear banding in NGs. In this study, Co-P NGs are investigated by molecular dynamics simulations to reveal the phenomenon of elemental segregation in the GGI regions where the content of Co is dominant. Specifically, Co segregation results in the formation of GGIs, whose atomic structures are comparatively less dense than those present in the interiors of glassy grains. It is suggested that the Co segregation significantly reduces the shear resistance of GGIs. Thus, such compositional heterogeneity influences the mechanical properties of Co-P NGs. Particularly, shear banding is much altered through enhancing the Co segregation in the GGI regions, which leads to improvements in the ductility of Co-P NGs. This study advances knowledge of the formation of the GGI phase in NGs, which could enable GGI engineering in enhancing the mechanical properties of NGs.

17.
BMC Public Health ; 24(1): 1664, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909210

RESUMO

BACKGROUND: Obesity is a global health problem, and its connection with social and environmental factors is well-established. Social factors, such as urban segregation, may impact obesity through various mechanisms, including food and physical activity environments, as well as social norms and networks. This multilevel study aims to examine the effect of socio-economic residential segregation of Latin American cities on the obesity of individuals within those cities. METHODS: We analyzed data from national surveys for a total of 59,340 individuals of 18-70 years of age, conducted in 156 cities across Brazil, Chile, Colombia, and Mexico between 2007 and 2013. We adjusted two-level linear mixed models for body mass index (BMI) stratified by sex and country, controlling for age, educational level and poverty. Separate models were built for dissimilarity and isolation segregation indices. RESULTS: The relationships between segregation indices and BMI were mostly not statistically significant, and in some cases, they were opposite to what was expected. The only significant relationships were observed in Colombian men, using the dissimilarity index (-7.5 [95% CI: -14.4, -0.5]) and in Colombian women, using the isolation index (-7.9 [95% CI: -14.1, -1.7]). CONCLUSIONS: While individual-level factors cannot fully explain differences among people in the same city, segregation indices may help. However, we found that in some cases, the relationship between BMI and segregation indices is opposite to what is expected based on prior literature. This should be considered in examining the phenomenon. Further research on obesogenic environments in segregated neighborhoods could provide valuable evidence.


Assuntos
Índice de Massa Corporal , Cidades , Obesidade , Características de Residência , Segregação Social , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Adolescente , Idoso , Adulto Jovem , América Latina , Características de Residência/estatística & dados numéricos , Obesidade/epidemiologia , Fatores Socioeconômicos , Colômbia , Segregação Residencial
18.
Sci Rep ; 14(1): 14298, 2024 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-38906922

RESUMO

Bovine tuberculosis (bTB) is endemic and has a substantial impact on the livestock sector in Ethiopia and other low and middle-income countries (LMICs). With a national emphasis on dairy farm intensification to boost milk production and spur economic growth, the incidence of bTB is anticipated to rise. However, Ethiopia, like other LMICs, lacks a comprehensive national bTB control strategy due to the economic and social infeasibility of traditional test-and-cull (TC) approaches. To inform the development of such a strategy, we evaluated the effectiveness and feasibility of TC and test-and-segregation (TSg) strategies for bTB control on Ethiopian dairy farms. A TC approach was used at Farm A [N = 62; comparative cervical test (CCT) > 4 mm, starting prevalence 11.3%] while TSg was implemented at Farm B (N = 45; CCT > 4 mm, prevalence 22.2%), with testing intervals of 2-4 months. Both strategies achieved a reduction in bTB prevalence to 0%, requiring seven rounds of TC over 18 months at Farm A, and five rounds of TSg over 12 months at Farm B's negative herd. The results show that adopting more sensitive thresholds [CCT > 0 mm or single cervical test (SCT) > 2 mm] during later rounds was pivotal in identifying and managing previously undetected infections, emphasizing the critical need for optimized diagnostic thresholds. Cost analysis revealed that TC was approximately twice as expensive as TSg, primarily due to testing, labor, and cow losses in TC, versus construction of new facilities and additional labor for TSg. This underscores the economic and logistical challenges of bTB management in resource-limited settings. Taken together, our study highlights an urgent need for the exploration of alternative approaches including TSg and or vaccination to mitigate within herd transmission and enable implementation of bTB control in regions where TC is not feasible.


Assuntos
Indústria de Laticínios , Estudos de Viabilidade , Tuberculose Bovina , Bovinos , Animais , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/prevenção & controle , Tuberculose Bovina/diagnóstico , Etiópia/epidemiologia , Indústria de Laticínios/métodos , Prevalência , Fazendas , Feminino , Mycobacterium bovis
19.
Proc Natl Acad Sci U S A ; 121(25): e2323009121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38875144

RESUMO

Error correction is central to many biological systems and is critical for protein function and cell health. During mitosis, error correction is required for the faithful inheritance of genetic material. When functioning properly, the mitotic spindle segregates an equal number of chromosomes to daughter cells with high fidelity. Over the course of spindle assembly, many initially erroneous attachments between kinetochores and microtubules are fixed through the process of error correction. Despite the importance of chromosome segregation errors in cancer and other diseases, there is a lack of methods to characterize the dynamics of error correction and how it can go wrong. Here, we present an experimental method and analysis framework to quantify chromosome segregation error correction in human tissue culture cells with live cell confocal imaging, timed premature anaphase, and automated counting of kinetochores after cell division. We find that errors decrease exponentially over time during spindle assembly. A coarse-grained model, in which errors are corrected in a chromosome-autonomous manner at a constant rate, can quantitatively explain both the measured error correction dynamics and the distribution of anaphase onset times. We further validated our model using perturbations that destabilized microtubules and changed the initial configuration of chromosomal attachments. Taken together, this work provides a quantitative framework for understanding the dynamics of mitotic error correction.


Assuntos
Segregação de Cromossomos , Cinetocoros , Microtúbulos , Mitose , Fuso Acromático , Humanos , Cinetocoros/metabolismo , Fuso Acromático/metabolismo , Microtúbulos/metabolismo , Anáfase , Modelos Biológicos , Células HeLa
20.
Artigo em Inglês | MEDLINE | ID: mdl-38920133

RESUMO

The high performance of intermediate-to-low temperature solid oxide fuel cells (ILT-SOFCs) closely depends on the catalytic activity of the cathode material. However, most high-activity perovskite cathodes are rich in Sr and will arise from Sr segregation during the long-term working, resulting in the decay of activity and stability. Herein, by regulating the calcined way and temperature, a type of self-assembled nanocomposite perovskite cathode is developed, the stoichiometric SrCo0.7Fe0.2Sc0.1O3-δ (SCFSc) powder self-separates into a cubic phase (Pm3̅m, Sc-rich) and a tetragonal phase (P4/mmm, Sc-fewer). Meanwhile, a single cubic phase is prepared with the same formula via calcining the SCFSc pellet. It is found that the nanocomposite cathode shows better oxygen reduction reaction catalytic activity than single cubic SCFSc, caused by lower impedance of oxygen surface exchange and bulk diffusion. Particularly, the nanocomposite SCFSc cathode with the self-assembled heterointerfaces mitigates the Sr segregation and shows a peak power density of 1.17 W cm-2 at 700 °C and excellent stability for ∼101 h at 600 °C. This work provides a strategy for the development of nanocomposite cathodes to mitigate cation segregation and improve catalytic activity and stability.

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