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1.
Interface Focus ; 14(3): 20230073, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39081629

RESUMEN

In this study, we explore the innovative application of biological principles of scattering foams and structural colouration of white materials to manipulate the transmission properties of thermal infrared (IR) radiation, particularly within the 8-14 µm wavelength range in polyolefin materials. Inspired by the complex skin of organisms such as chameleons, which can dynamically change colour through structural alterations, as well as more mundane technologies such as Buddha Boards and magic water colouring books, we are developing methods to control thermal IR transmission using common thermoplastic materials that are semi-transparent to thermal IR radiation. Polyethylene and polypropylene, known for their versatility and cost-effectiveness, can be engineered into microstructured sheets with feature sizes spanning from 5 to 100 µm. By integrating these precisely moulded microstructures with index-matching fluids, specifically IR transparent oils, we achieve a reversible modification of the thermal transmission properties. This novel approach not only mimics the adaptive functionality of natural systems but also offers a practical and scalable solution for dynamic thermal management. Our results indicate a promising pathway for the development of new materials that can adapt their IR properties in real time, paving the way for smarter thermal management solutions via radiative emission/absorption.

2.
Proc Natl Acad Sci U S A ; 121(9): e2306554121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38377187

RESUMEN

The national context of deportation threat, defined as the federal government's approach to deportation and/or deportation's salience to the US public, fluctuated between 2011 and 2018. US Latinos across citizenship statuses may have experienced growing psychological distress associated with these changes, given their disproportionate personal or proximal vulnerabilities to deportation. Drawing on 8 y of public- and restricted-access data from the National Health Interview Survey (2011 to 2018), this article examines trends in psychological distress among Latinos who are US-born citizens, naturalized citizens, and noncitizens. It then seeks to explain these trends by considering two theoretical pathways through which the national context of deportation threat could distress Latinos: 1) through discrete dramatic societal events that independently signal a change to the country's approach to deportation and/or that render deportation temporarily more salient to the public or 2) through more gradual changes to the country's everyday institutional (i.e., quotidian efforts to detain and deport noncitizens) and social (i.e., deportation's ongoing salience to a concerned public) environment of deportation threat. We find that, though both pathways matter to some degree, there is more consistent evidence that the gradual changes are associated with Latino US citizens and noncitizens' overall experiences of psychological distress. The article highlights how, even absent observable spillover effects of dramatic societal events bearing on deportation threat, the institutional and social environment in which they occur implicates Latinos' well-being.


Asunto(s)
Emigrantes e Inmigrantes , Distrés Psicológico , Humanos , Estados Unidos , Deportación , Hispánicos o Latinos/psicología , Encuestas y Cuestionarios , Medio Social
3.
Micromachines (Basel) ; 14(12)2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38138396

RESUMEN

We present in this work new methodologies to produce, refine, and interconnect room-temperature liquid-metal-core thermoplastic elastomer wires that have extreme extendibility (>500%), low production time and cost at scale, and may be integrated into commonly used electrical prototyping connectors like a Japan Solderless Terminal (JST) or Dupont connectors. Rather than focus on the development of a specific device, the aim of this work is to demonstrate strategies and processes necessary to achieve scalable production of liquid-metal-enabled electronics and address several key challenges that have been present in liquid metal systems, including leak-free operation, minimal gallium corrosion of other electrode materials, low liquid metal consumption, and high production rates. The ultimate goal is to create liquid-metal-enabled rapid prototyping technologies, similar to what can be achieved with Arduino projects, where modification and switching of components can be performed in seconds, which enables faster iterations of designs. Our process is focused primarily on fibre-based liquid metal wires contained within thermoplastic elastomers. These fibre form factors can easily be integrated with wearable sensors and actuators as they can be sewn or woven into fabrics, or cast within soft robotic components.

4.
Micromachines (Basel) ; 12(7)2021 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-34208985

RESUMEN

Protective textiles used for military applications must fulfill a variety of functional requirements, including durability, resistance to environmental conditions and ballistic threats, all while being comfortable and lightweight. In addition, these textiles must provide camouflage and concealment under various environmental conditions and, thus, a range of wavelengths on the electromagnetic spectrum. Similar requirements may exist for other applications, for instance hunting. With improvements in infrared sensing technology, the focus of protective textile research and development has shifted solely from providing visible camouflage to providing camouflage in the infrared (IR) region. Smart textiles, which can monitor and react to the textile wearer or environmental stimuli, have been applied to protective textiles to improve camouflage in the IR spectral range. This study presents a review of current smart textile technologies for visible and IR signature control of protective textiles, including coloration techniques, chromic materials, conductive polymers, and phase change materials. We propose novel fabrication technology combinations using various microfabrication techniques (e.g., three-dimensional (3D) printing; microfluidics; machine learning) to improve the visible and IR signature management of protective textiles and discuss possible challenges in terms of compatibility with the different textile performance requirements.

5.
Proc Natl Acad Sci U S A ; 117(16): 8836-8844, 2020 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-32253307

RESUMEN

Deportation has become more commonplace in the United States since the mid-2000s. Latin American noncitizens-encompassing undocumented and documented immigrants-are targeted for deportation. Deportation's threat also reaches naturalized and US-born citizens of Latino descent who are largely immune to deportation but whose loved ones or communities are deportable. Drawing on 6 y of data from the National Survey of Latinos, this article examines whether and how Latinos' deportation fears vary by citizenship and legal status and over time. Compared with Latino noncitizens, Latino US citizens report lower average deportation fears. However, a more complex story emerges when examining this divide over time: Deportation fears are high but stable among Latino noncitizens, whereas deportation fears have increased substantially among Latino US citizens. These trends reflect a growing national awareness of-rather than observable changes to-deportation policy and practice since the 2016 US presidential election. The article highlights how deportation or its consequences affects a racial group that the US immigration regime targets disproportionately.


Asunto(s)
Emigrantes e Inmigrantes/psicología , Emigración e Inmigración/legislación & jurisprudencia , Miedo , Hispánicos o Latinos/psicología , Adulto , Factores de Edad , Estudios Transversales , Emigrantes e Inmigrantes/legislación & jurisprudencia , Emigrantes e Inmigrantes/estadística & datos numéricos , Emigración e Inmigración/estadística & datos numéricos , Femenino , Hispánicos o Latinos/legislación & jurisprudencia , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Factores Sexuales , Encuestas y Cuestionarios/estadística & datos numéricos , Estados Unidos
6.
Micromachines (Basel) ; 11(1)2020 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-31963872

RESUMEN

Hydrogel-facilitated phase separation (HFPS) has recently been applied to make microstructured porous membranes by modified phase separation processes. In HFPS, a soft lithographically patterned hydrogel mold is used as a water content source that initiates the phase separation process in membrane fabrication. However, after each membrane casting, the hydrogel content changes due to the diffusion of organic solvent into the hydrogel from the original membrane solution. The absorption of solvent into the hydrogel mold limits the continuous use of the mold in repeated membrane casts. In this study, we investigated a simple treatment process for hydrogel mold recovery, consisting of warm and cold treatment steps to provide solvent extraction without changing the hydrogel mold integrity. The best recovery result was 96%, which was obtained by placing the hydrogel in a warm water bath (50 °C) for 10 min followed by immersing in a cold bath (23 °C) for 4 min and finally 4 min drying in air. This recovery was attributed to nearly complete solvent extraction without any deformation of the hydrogel structure. The reusability of hydrogel can assist in the development of a continuous membrane fabrication process using HFPS.

7.
Chemosphere ; 238: 124691, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31524626

RESUMEN

In recent years, forward osmosis (FO) has represented numerous potential applications in safe water production. In this study, we improved the performance of FO thin film composite (TFC) membranes for the removal of trace organic compounds (TOrCs) by tuning the chemistry of its top active layer. The TFC membranes were synthesized by interfacial polymerization (IP) reaction between amine-containing monomers, e.g., meta-phenylene diamine (MPD) or para-phenylenediamine (PPD), and an acid chloride monomer, e.g., trimesoyl chloride (TMC). Owing to three free amine functionals over main core, melamine was used in the amine monomers solution to increase cross-linking among polyamide chains. Chemical and morphological characterization of the prepared membranes confirmed that melamine was successfully incorporated into the chemical structure of the top PA layer. Two agricultural toxic materials (atrazine and diazinon) were used to investigate the capability of the newly fabricated membranes in the removal of TOrCs. The obtained results showed that melamine-improved FO membranes provided higher atrazine and diazinon rejections in two different FO membrane configurations, including active layer facing feed solution (ALF) and active layer facing draw solution (ALD). The highest rejections of both diazinon (99.4%) and atrazine (97.3%) were achieved when the melamine modified MPD-based membrane served in ALF mode with 2 M NaCl as a draw solution.


Asunto(s)
Sustancias Húmicas/análisis , Ósmosis/fisiología , Purificación del Agua/instrumentación , Purificación del Agua/métodos , Atrazina/análisis , Diazinón/análisis , Membranas Artificiales , Nylons/química , Fenilendiaminas/química , Polimerizacion , Cloruro de Sodio/química , Triazinas/química , Ácidos Tricarboxílicos/química , Agua/química
8.
J Pak Med Assoc ; 69(9): 1380-1382, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31511730

RESUMEN

Sacral insufficiency fracture is a rare complication of the lumbar spinal surgery. It is normally reported as a late complication of the multi-segment spinal fixation in females with osteoporotic bone. We present the case of an elderly gentleman who suffered this complication spontaneously on the second postoperative day. To the best of our knowledge this has never been reported in Pakistan. Sacral alae are directly in line with weight bearingwhile walking and should be kept in mind when mobilizing a postoperative patient whose previous history indicates such risk factors. Once injury is suspected, CT scan is recommended as x-rays may not always reveal the injury. In literature, these fractures have almost always been treated conservatively.1 Conservative management wasnot tolerated well in our case and we proceeded with surgical management using S2 sacral alar iliac screws (S2 AI screws) to extend the previous lumbosacral fusion construct. S2 AI screws are a novel technique used for bone lumbosacral fusion and studies have shown to have lower rate of screw breakage under stress and need for revision surgery with their use.


Asunto(s)
Fracturas Espontáneas/diagnóstico por imagen , Fracturas por Estrés/diagnóstico por imagen , Complicaciones Posoperatorias/diagnóstico por imagen , Sacro/lesiones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fusión Vertebral , Anciano , Reposo en Cama , Tratamiento Conservador , Descompresión Quirúrgica , Fijación Interna de Fracturas , Fracturas Espontáneas/cirugía , Fracturas por Estrés/cirugía , Humanos , Vértebras Lumbares/cirugía , Masculino , Complicaciones Posoperatorias/cirugía , Sacro/diagnóstico por imagen , Sacro/cirugía , Fracturas de la Columna Vertebral/cirugía , Estenosis Espinal/cirugía , Tomografía Computarizada por Rayos X
9.
Soc Sci Med ; 199: 19-28, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28359580

RESUMEN

This article advances the concept of racialized legal status (RLS) as an overlooked dimension of social stratification with implications for racial/ethnic health disparities. We define RLS as a social position based on an ostensibly race-neutral legal classification that disproportionately impacts racial/ethnic minorities. To illustrate the implications of RLS for health and health disparities in the United States, we spotlight existing research on two cases: criminal status and immigration status. We offer a conceptual framework that outlines how RLS shapes disparities through (1) primary effects on those who hold a legal status and (2) spillover effects on racial/ethnic in-group members, regardless of these individuals' own legal status. Primary effects of RLS operate by marking an individual for material and symbolic exclusion. Spillover effects result from the vicarious experiences of those with social proximity to marked individuals, as well as the discredited meanings that RLS constructs around racial/ethnic group members. We conclude by suggesting multiple avenues for future research that considers RLS as a mechanism of social inequality with fundamental effects on health.


Asunto(s)
Criminales/legislación & jurisprudencia , Emigración e Inmigración/legislación & jurisprudencia , Etnicidad/estadística & datos numéricos , Disparidades en el Estado de Salud , Grupos Minoritarios/estadística & datos numéricos , Grupos Raciales/estadística & datos numéricos , Determinantes Sociales de la Salud/etnología , Adulto , Criminales/estadística & datos numéricos , Humanos , Masculino , Estados Unidos , Adulto Joven
10.
Health Psychol ; 36(5): 411-418, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27929328

RESUMEN

OBJECTIVE: Previous research shows that migraine and general headache symptoms increase after traumatic events. Questions remain about whether posttraumatic stress disorder (PTSD) produces migraine/headache symptoms, or if individuals afflicted by migraine/headache are especially likely to develop PTSD. We test whether PTSD symptoms following a natural disaster are associated with higher odds of reporting frequent headaches/migraines postdisaster. We decompose PTSD into intrusion, avoidance, and hyperarousal symptom clusters to examine which, if any, are uniquely related to headache/migraine postdisaster. METHOD: We use prospectively collected pre- and postdisaster data to explore whether overall PTSD symptoms and symptom clusters are associated with migraine/headache in a sample of Hurricane Katrina survivors. We account for severity of hurricane exposure and control for baseline migraine and headache problems to reduce the probability that heightened PTSD susceptibility among those who already suffered from the conditions could explain observed associations. RESULTS: PTSD symptoms were associated with higher odds of experiencing frequent headaches or migraines with a standard deviation change in PTSD score corresponding to over twice the odds (95% confidence interval [1.64, 2.68]) of having trouble with frequent headaches or migraines in the post-Katrina period. Each additional point on the intrusion subscale (sample M [SD] = 1.6 [1.1]) was associated with 55% higher odds of reporting frequent headache/migraine (95% confidence interval [1.03, 2.33]), but we found no association with avoidance or hyperarousal symptoms. CONCLUSIONS: Clinicians and disaster planners should be aware that disaster survivors might be at heightened risk of migraine/headache episodes, and those experiencing intrusive reminders may be most affected. (PsycINFO Database Record


Asunto(s)
Desastres , Trastornos Migrañosos/etiología , Trastornos por Estrés Postraumático/complicaciones , Estrés Psicológico/psicología , Sobrevivientes/psicología , Adulto , Femenino , Humanos , Masculino , Trastornos Migrañosos/patología , Estudios Prospectivos , Trastornos por Estrés Postraumático/psicología
11.
Soc Sci Med ; 144: 79-87, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26397866

RESUMEN

Although a substantial literature examines the relationship between culture and health in myriad individual contexts, a lack of comparative data across settings has resulted in disparate and imprecise conceptualizations of the concept for scholars and practitioners alike. This article examines scholars and practitioners' understandings of culture in relation to health interventions. Drawing on 169 interviews with officials from three different nongovernmental organizations working on health issues in multiple countries-Partners in Health, Oxfam America, and Sesame Workshop-we examine how these respondents' interpretations of culture converge or diverge with recent developments in the study of the concept, as well as how these understandings influence health interventions at three different stages-design, implementation, and evaluation-of a project. Based on these analyses, a tripartite definition of culture is built-as knowledge, practice, and change-and these distinct conceptualizations are linked to the success or failure of a project at each stage of an intervention. In so doing, the study provides a descriptive and analytical starting point for scholars interested in understanding the theoretical and empirical relevance of culture for health interventions, and sets forth concrete recommendations for practitioners working to achieve robust improvements in health outcomes.


Asunto(s)
Cultura , Organizaciones/organización & administración , Salud Pública/métodos , Salud Global , Conocimientos, Actitudes y Práctica en Salud , Humanos , Entrevistas como Asunto , Desarrollo de Programa/métodos , Administración en Salud Pública , Investigación Cualitativa
12.
Popul Environ ; 36(3): 279-310, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32999520

RESUMEN

Current theories conceptualize return migration to New Orleans after Hurricane Katrina as an individual-level assessment of costs and benefits. Since relocation is cost prohibitive, return migration is thought to be unlikely for vulnerable populations. However, recent analyses of longitudinal survey data suggest that these individuals are likely to return to New Orleans over time despite achieving socioeconomic gains in the post-disaster location. I extend the "context of reception" approach from the sociology of immigration and draw on longitudinal data from the Resilience in the Survivors of Katrina Project to demonstrate how institutional, labor market, and social contexts influence the decision to return. Specifically, I show how subjective comparisons of the three contexts between origin and destination, perceived experiences of discrimination within each context, and changing contexts over time explain my sample's divergent migration and mobility outcomes. I conclude with implications for future research on, and policy responses to, natural disasters.

13.
Soc Sci Med ; 120: 325-33, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24852816

RESUMEN

Social scientists have fiercely debated the relationship between non-governmental organizations (NGOs) and the state in NGO-led development projects. However, this research often carries an implicit, and often explicit, anti-state bias, suggesting that when NGOs collaborate with states, they cease to be a progressive force. This literature thus fails to recognize the state as a complex, heterogeneous, and fragmented entity. In particular, the unique political context within which an NGO operates is likely to influence how it carries out its work. In this article, we ask: how do NGOs work and build relationships with different types of states and--of particular relevance to practitioners--what kinds of relationship building lead to more successful development outcomes on the ground? Drawing on 29 in-depth interviews with members of Partners in Health and Oxfam America conducted between September 2010 and February 2014, we argue that NGOs and their medical humanitarian projects are more likely to succeed when they adjust how they interact with different types of states through processes of interest harmonization and negotiation. We offer a theoretical model for understanding how these processes occur across organizational fields. Specifically, we utilize field overlap theory to illuminate how successful outcomes depend on NGOs' ability to leverage resources--alliances and networks; political, financial, and cultural resources; and frames--across state and non-state fields. By identifying how NGOs can increase the likelihood of project success, our research should be of interest to activists, practitioners, and scholars.


Asunto(s)
Altruismo , Conducta Cooperativa , Atención a la Salud , Organizaciones , Desarrollo de Programa , Entrevistas como Asunto , Modelos Teóricos , Estudios de Casos Organizacionales , Investigación Cualitativa
14.
Soc Sci Med ; 106: 53-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24534732

RESUMEN

The number of human cadavers available for medical research and training, as well as organ transplantation, is limited. Researchers disagree about how to increase the number of whole-body bequeathals, citing a shortage of donations from the one group perceived as most likely to donate from attitudinal survey data - educated white males over 65. This focus on survey data, however, suffers from two main limitations: First, it reveals little about individuals' actual registration or donation behavior. Second, past studies' reliance on average survey measures may have concealed variation within the donor population. To address these shortcomings, we employ cluster analysis on all whole-body donors' data from the Universities of California at Davis, Irvine, Los Angeles, and San Francisco. Two donor groups emerge from the analyses: One is made of slightly younger, educated, married individuals, an overwhelming portion of whom are U.S.-born and have U.S.-born parents, while the second includes mostly older, separated women with some college education, a relatively higher share of whom are foreign-born and have foreign-born parents. Our results demonstrate the presence of additional donor groups within and beyond the group of educated and elderly white males previously assumed to be most likely to donate. More broadly, our results suggest how the intersectional nature of donors' demographics - in particular, gender and migration status - shapes the configuration of the donor pool, signaling new ways to possibly increase donations.


Asunto(s)
Donantes de Tejidos/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Investigación Biomédica , Cadáver , California , Análisis por Conglomerados , Emigración e Inmigración/estadística & datos numéricos , Femenino , Humanos , Masculino , Factores Sexuales
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