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1.
Nature ; 577(7788): 74-78, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894145

RESUMEN

To address global challenges1-4, 193 countries have committed to the 17 United Nations Sustainable Development Goals (SDGs)5. Quantifying progress towards achieving the SDGs is essential to track global efforts towards sustainable development and guide policy development and implementation. However, systematic methods for assessing spatio-temporal progress towards achieving the SDGs are lacking. Here we develop and test systematic methods to quantify progress towards the 17 SDGs at national and subnational levels in China. Our analyses indicate that China's SDG Index score (an aggregate score representing the overall performance towards achieving all 17 SDGs) increased at the national level from 2000 to 2015. Every province also increased its SDG Index score over this period. There were large spatio-temporal variations across regions. For example, eastern China had a higher SDG Index score than western China in the 2000s, and southern China had a higher SDG Index score than northern China in 2015. At the national level, the scores of 13 of the 17 SDGs improved over time, but the scores of four SDGs declined. This study suggests the need to track the spatio-temporal dynamics of progress towards SDGs at the global level and in other nations.


Asunto(s)
Desarrollo Sostenible/tendencias , China , Tiempo
4.
Kidney Int ; 100(6): 1227-1239, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34537228

RESUMEN

Anemia is a common complication of chronic kidney disease, affecting the quality of life of patients. Among various factors, such as iron and erythropoietin deficiency, reduced red blood cell (RBC) lifespan has been implicated in the pathogenesis of anemia. However, mechanistic data on in vivo RBC dysfunction in kidney disease are lacking. Herein, we describe the development of chronic kidney disease-associated anemia in mice with proteinuric kidney disease resulting from either administration of doxorubicin or an inducible podocin deficiency. In both experimental models, anemia manifested at day 10 and progressed at day 30 despite increased circulating erythropoietin levels and erythropoiesis in the bone marrow and spleen. Circulating RBCs in both mouse models displayed altered morphology and diminished osmotic-sensitive deformability together with increased phosphatidylserine externalization on the outer plasma membrane, a hallmark of RBC death. Fluorescence-labelling of RBCs at day 20 of mice with doxorubicin-induced kidney disease revealed premature clearance from the circulation. Metabolomic analyses of RBCs from both mouse models demonstrated temporal changes in redox recycling pathways and Lands' cycle, a membrane lipid remodeling process. Anemic patients with proteinuric kidney disease had an increased proportion of circulating phosphatidylserine-positive RBCs. Thus, our observations suggest that reduced RBC lifespan, mediated by altered RBC metabolism, reduced RBC deformability, and enhanced cell death contribute to the development of anemia in proteinuric kidney disease.


Asunto(s)
Anemia , Insuficiencia Renal Crónica , Anemia/inducido químicamente , Animales , Eritrocitos , Humanos , Longevidad , Ratones , Calidad de Vida , Insuficiencia Renal Crónica/complicaciones
5.
Opt Express ; 28(8): 11415-11423, 2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32403653

RESUMEN

An ultrafast Yb-doped thin-disk multi-pass laser amplifier system with flexible parameters for material processing is reported. We can generate bursts consisting of four pulses at a distance of 20 ns and a total energy of 46.7 mJ at a repetition rate of 25 kHz. In single-pulse operation, 1.5 kW of average output is achieved at 400 kHz when optimizing for a beam quality of M2 = 1.5. Alignment for maximum output power provides 1.9 kW at the same repetition rate. All results are obtained without chirped-pulse amplification in the multi-pass set-up. The application potential of the system is demonstrated exploring its performance in materials processing of dielectrics. Cleaving of 3.8-mm-thick SCHOTT borofloat glass with a velocity of 1200 mm/s is demonstrated with 300 W of input power. Single-pass modification of 30 mm borosilicate glass is enabled with a Bessel beam at 1 kW of average power delivered by four-pulse bursts of an energy of 30 mJ.

6.
Cell Commun Signal ; 18(1): 155, 2020 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-32948210

RESUMEN

BACKGROUND: Thrombospondin-1 (TSP-1), a Ca2+-binding trimeric glycoprotein secreted by multiple cell types, has been implicated in the pathophysiology of several clinical conditions. Signaling involving TSP-1, through its cognate receptor CD47, orchestrates a wide array of cellular functions including cytoskeletal organization, migration, cell-cell interaction, cell proliferation, autophagy, and apoptosis. In the present study, we investigated the impact of TSP-1/CD47 signaling on Ca2+ dynamics, survival, and deformability of human red blood cells (RBCs). METHODS: Whole-cell patch-clamp was employed to examine transmembrane cation conductance. RBC intracellular Ca2+ levels and multiple indices of RBC cell death were determined using cytofluorometry analysis. RBC morphology and microvesiculation were examined using imaging flow cytometry. RBC deformability was measured using laser-assisted optical rotational cell analyzer. RESULTS: Exposure of RBCs to recombinant human TSP-1 significantly increased RBC intracellular Ca2+ levels. As judged by electrophysiology experiments, TSP-1 treatment elicited an amiloride-sensitive inward current alluding to a possible Ca2+ influx via non-selective cation channels. Exogenous TSP-1 promoted microparticle shedding as well as enhancing Ca2+- and nitric oxide-mediated RBC cell death. Monoclonal (mouse IgG1) antibody-mediated CD47 ligation using 1F7 recapitulated the cell death-inducing effects of TSP-1. Furthermore, TSP-1 treatment altered RBC cell shape and stiffness (maximum elongation index). CONCLUSIONS: Taken together, our data unravel a new role for TSP-1/CD47 signaling in mediating Ca2+ influx into RBCs, a mechanism potentially contributing to their dysfunction in a variety of systemic diseases. Video abstract.


Asunto(s)
Antígeno CD47/metabolismo , Deformación Eritrocítica , Eritrocitos/citología , Transducción de Señal , Trombospondina 1/metabolismo , Calcio/metabolismo , Cationes Bivalentes/metabolismo , Supervivencia Celular , Membrana Eritrocítica/metabolismo , Eritrocitos/metabolismo , Humanos
7.
Proc Natl Acad Sci U S A ; 112(27): 8254-9, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26080396

RESUMEN

Starting at least in the 1970s, empirical work suggested that demographic (population) and economic (affluence) forces are the key drivers of anthropogenic stress on the environment. We evaluate the extent to which politics attenuates the effects of economic and demographic factors on environmental outcomes by examining variation in CO2 emissions across US states and within states over time. We find that demographic and economic forces can in part be offset by politics supportive of the environment--increases in emissions over time are lower in states that elect legislators with strong environmental records.


Asunto(s)
Dióxido de Carbono/análisis , Efecto Invernadero/economía , Efecto Invernadero/legislación & jurisprudencia , Política , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/legislación & jurisprudencia , Política Ambiental/legislación & jurisprudencia , Gases/análisis , Humanos , Modelos Teóricos , Análisis de Regresión , Estados Unidos
8.
Chemistry ; 23(62): 15583-15587, 2017 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-28869692

RESUMEN

The homodinuclear ruthenium(II) complex [{Ru(l-N4 Me2 )}2 (µ-tape)](PF6 )4 {[1](PF6 )4 } (l-N4 Me2 =N,N'-dimethyl-2,11-diaza[3.3](2,6)-pyridinophane, tape=1,6,7,12-tetraazaperylene) can store one or two electrons in the energetically low-lying π* orbital of the bridging ligand tape. The corresponding singly and doubly reduced complexes [{Ru(l-N4 Me2 )}2 (µ-tape.- )](PF6 )3 {[2](PF6 )3 } and [{Ru(l-N4 Me2 )}2 (µ-tape2- )](PF6 )2 {[3](PF6 )2 }, respectively, were electrochemically generated, successfully isolated and fully characterized by single-crystal X-ray crystallography, spectroscopic methods and magnetic susceptibility measurements. The singly reduced complex [2](PF6 )3 contains the π-radical tape.- and the doubly reduced [3](PF6 )2 the diamagnetic dianion tape2- as bridging ligand, respectively. Nucleophilic aromatic substitution at the bridging tape in [1]4+ by two sulfite units gave the complex [{Ru(l-N4 Me2 )}2 {µ-tape-(SO3 )2 }]2+ ([4]2+ ). Complex dication [4]2+ was exploited as a redox mediator between an anaerobic homogenous reaction solution of an enzyme system (sulfite/sulfite oxidase) and the electrode via participation of the low-energy π*-orbital of the disulfonato-substituted bridging ligand tape-(SO3 )22- (Ered1 =-0.1 V versus Ag/AgCl/1 m KCl in water).

10.
Proc Natl Acad Sci U S A ; 110 Suppl 3: 14081-7, 2013 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-23940350

RESUMEN

Decisions always involve both facts and values, whereas most science communication focuses only on facts. If science communication is intended to inform decisions, it must be competent with regard to both facts and values. Public participation inevitably involves both facts and values. Research on public participation suggests that linking scientific analysis to public deliberation in an iterative process can help decision making deal effectively with both facts and values. Thus, linked analysis and deliberation can be an effective tool for science communication. However, challenges remain in conducting such process at the national and global scales, in enhancing trust, and in reconciling diverse values.


Asunto(s)
Comunicación , Difusión de la Información/métodos , Ciencia/métodos , Toma de Decisiones , Humanos , Opinión Pública
11.
Proc Natl Acad Sci U S A ; 115(49): 12334-12336, 2018 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-30459271
12.
Proc Natl Acad Sci U S A ; 110(27): 10916-21, 2013 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-23776222

RESUMEN

For decades, scholars have been trying to determine whether small or large groups are more likely to cooperate for collective action and successfully manage common-pool resources. Using data gathered from the Wolong Nature Reserve since 1995, we examined the effects of group size (i.e., number of households monitoring a single forest parcel) on both collective action (forest monitoring) and resource outcomes (changes in forest cover) while controlling for potential confounding factors. Our results demonstrate that group size has nonlinear effects on both collective action and resource outcomes, with intermediate group size contributing the most monitoring effort and leading to the biggest forest cover gain. We also show how opposing effects of group size directly and indirectly affect collective action and resource outcomes, leading to the overall nonlinear relationship. Our findings suggest why previous studies have observed differing and even contradictory group-size effects, and thus help guide further research and governance of the commons. The findings also suggest that it should be possible to improve collective action and resource outcomes by altering factors that lead to the nonlinear group-size effect, including punishing free riding, enhancing overall and within-group enforcement, improving social capital across groups and among group members, and allowing self-selection during the group formation process so members with good social relationships can form groups autonomously.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Animales , Biodiversidad , China , Conservación de los Recursos Naturales/estadística & datos numéricos , Ecosistema , Procesos de Grupo , Humanos , Dinámicas no Lineales , Apoyo Social , Árboles , Ursidae
15.
Proc Natl Acad Sci U S A ; 106(44): 18452-6, 2009 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-19858494

RESUMEN

Most climate change policy attention has been addressed to long-term options, such as inducing new, low-carbon energy technologies and creating cap-and-trade regimes for emissions. We use a behavioral approach to examine the reasonably achievable potential for near-term reductions by altered adoption and use of available technologies in US homes and nonbusiness travel. We estimate the plasticity of 17 household action types in 5 behaviorally distinct categories by use of data on the most effective documented interventions that do not involve new regulatory measures. These interventions vary by type of action and typically combine several policy tools and strong social marketing. National implementation could save an estimated 123 million metric tons of carbon per year in year 10, which is 20% of household direct emissions or 7.4% of US national emissions, with little or no reduction in household well-being. The potential of household action deserves increased policy attention. Future analyses of this potential should incorporate behavioral as well as economic and engineering elements.


Asunto(s)
Conducta , Carbono/análisis , Artículos Domésticos , Humanos , Estados Unidos
16.
Proc Natl Acad Sci U S A ; 106(5): 1305-12, 2009 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-19179280

RESUMEN

The Millennium Ecosystem Assessment (MA) introduced a new framework for analyzing social-ecological systems that has had wide influence in the policy and scientific communities. Studies after the MA are taking up new challenges in the basic science needed to assess, project, and manage flows of ecosystem services and effects on human well-being. Yet, our ability to draw general conclusions remains limited by focus on discipline-bound sectors of the full social-ecological system. At the same time, some polices and practices intended to improve ecosystem services and human well-being are based on untested assumptions and sparse information. The people who are affected and those who provide resources are increasingly asking for evidence that interventions improve ecosystem services and human well-being. New research is needed that considers the full ensemble of processes and feedbacks, for a range of biophysical and social systems, to better understand and manage the dynamics of the relationship between humans and the ecosystems on which they rely. Such research will expand the capacity to address fundamental questions about complex social-ecological systems while evaluating assumptions of policies and practices intended to advance human well-being through improved ecosystem services.


Asunto(s)
Ecosistema , Ambiente , Conservación de los Recursos Naturales , Humanos , Modelos Teóricos , Probabilidad , Especificidad de la Especie
17.
Biology (Basel) ; 11(5)2022 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-35625375

RESUMEN

Autologous blood doping (ABD) refers to the transfusion of one's own blood after it has been stored. Although its application is prohibited in sports, it is assumed that ABD is applied by a variety of athletes because of its benefits on exercise performance and the fact that it is not detectable so far. Therefore, this study aims at identifying changes in hematological and hemorheological parameters during the whole course of ABD procedure and to relate those changes to exercise performance. Eight healthy men conducted a 31-week ABD protocol including two blood donations and the transfusion of their own stored RBC volume corresponding to 7.7% of total blood volume. Longitudinal blood and rheological parameter measurements and analyses of RBC membrane proteins and electrolyte levels were performed. Thereby, responses of RBC sub-populations-young to old RBC-were detected. Finally, exercise tests were carried out before and after transfusion. Results indicate a higher percentage of young RBC, altered RBC deformability and electrolyte concentration due to ABD. In contrast, RBC membrane proteins remained unaffected. Running economy improved after blood transfusion. Thus, close analysis of RBC variables related to ABD detection seems feasible but should be verified in further more-detailed studies.

19.
Biology (Basel) ; 10(1)2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33440902

RESUMEN

Red blood cell (RBC) deformability is an essential component of microcirculatory function that appears to be enhanced by physiological shear stress, while being negatively affected by supraphysiological shears and/or free radical exposure. Given that blood contains RBCs with non-uniform physical properties, whether all cells equivalently tolerate mechanical and oxidative stresses remains poorly understood. We thus partitioned blood into old and young RBCs which were exposed to phenazine methosulfate (PMS) that generates intracellular superoxide and/or specific mechanical stress. Measured RBC deformability was lower in old compared to young RBCs. PMS increased total free radicals in both sub-populations, and RBC deformability decreased accordingly. Shear exposure did not affect reactive species in the sub-populations but reduced RBC nitric oxide synthase (NOS) activation and intriguingly increased RBC deformability in old RBCs. The co-application of PMS and shear exposure also improved cellular deformability in older cells previously exposed to reactive oxygen species (ROS), but not in younger cells. Outputs of NO generation appeared dependent on cell age; in general, stressors applied to younger RBCs tended to induce S-nitrosylation of RBC cytoskeletal proteins, while older RBCs tended to reflect markers of nitrosative stress. We thus present novel findings pertaining to the interplay of mechanical stress and redox metabolism in circulating RBC sub-populations.

20.
Am Psychol ; 76(1): 130-144, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32202817

RESUMEN

The Intergovernmental Panel on Climate Change has encouraged psychologists to become part of the integrated scientific effort to support the achievement of climate change targets such as keeping within 1.5°C or 2°C of global warming. To date, the typical psychological approach has been to demonstrate that specific concepts and theories can predict behaviors that contribute to or mitigate climate change. Psychologists need to go further and, in particular, show that integrating psychological concepts into feasible interventions can reduce greenhouse gas emissions far more than would be achieved without such integration. While critiquing some aspects of current approaches, we describe psychological research that is pointing the way by distinguishing different types of behavior, acknowledging sociocultural context, and collaborating with other disciplines. Engaging this challenge offers psychologists new opportunities for promoting mitigation, advancing psychological understanding, and developing better interdisciplinary interactions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Asunto(s)
Calentamiento Global/prevención & control , Psicología , Humanos
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