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1.
Nature ; 634(8032): 57-60, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39358522

RESUMEN

Thunderstorms emit fluxes of gamma rays known as gamma-ray glows1,2, sporadically observed by aircraft1,3-7, balloons8-11 and from the ground12-18. Observations report increased gamma-ray emissions by tens of percent up to two orders of magnitude above the background, sometimes abruptly terminated by lightning discharges1,3-5. Glows are produced by the acceleration of energetic electrons in high-electric-field regions within thunderclouds8 and contribute to charge dissipation3. Glows had been considered as quasi-stationary phenomena3,5,12, with durations up to a few tens of seconds and spatial scales up to 10-20 km. However, no measurements of the full extension in space and time of a gamma-ray-glow region and their occurring frequency have been reported so far. Here we show that tropical thunderclouds over ocean and coastal regions commonly emit gamma rays for hours over areas up to a few thousand square kilometres. Emission is associated with deep convective cores; it is not uniform and continuous but shows characteristic timescales of 1-10 s and even subsecond for individual glows. The dynamics of gamma-glowing thunderclouds strongly contradicts the quasi-stationary picture of glows and instead resembles that of a huge gamma-glowing 'boiling pot' in both pattern and behaviour.

2.
Nature ; 634(8032): 53-56, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39358523

RESUMEN

Two different hard-radiation phenomena are known to originate from thunderclouds: terrestrial gamma-ray flashes (TGFs)1 and gamma-ray glows2. Both involve an avalanche of electrons accelerated to relativistic energies but are otherwise different. Glows are known to last for one to hundreds of seconds, have moderate intensities and originate from quasi-stationary thundercloud fields2-5. TGFs exhibit high intensities and have characteristic durations of tens to hundreds of microseconds6-9. TGFs often show a close association with an emission of strong radio signals10-17 and optical pulses18-21, which indicates the involvement of lightning leaders in their generation. Here we report unique observations of a different phenomenon, which we call flickering gamma-ray flashes (FGFs). FGFs resemble the usual multi-pulse TGFs22-24 but have more pulses and each pulse has a longer duration than ordinary TGFs. FGF durations span from 20 to 250 ms, which reaches the lower boundary of the gamma-ray glow duration. FGFs are radio and optically silent, which makes them distinct from normal TGFs. An FGF starts as an ordinary gamma-ray glow, then suddenly increases exponentially in intensity and turns into an unstable, 'flickering' mode with a sequence of pulses. FGFs could be the missing link between the gamma-ray glows and conventional TGFs, whose absence has been puzzling the atmospheric electricity community for two decades.

3.
Proc Natl Acad Sci U S A ; 119(7)2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-35131937

RESUMEN

Land use is central to addressing sustainability issues, including biodiversity conservation, climate change, food security, poverty alleviation, and sustainable energy. In this paper, we synthesize knowledge accumulated in land system science, the integrated study of terrestrial social-ecological systems, into 10 hard truths that have strong, general, empirical support. These facts help to explain the challenges of achieving sustainability in land use and thus also point toward solutions. The 10 facts are as follows: 1) Meanings and values of land are socially constructed and contested; 2) land systems exhibit complex behaviors with abrupt, hard-to-predict changes; 3) irreversible changes and path dependence are common features of land systems; 4) some land uses have a small footprint but very large impacts; 5) drivers and impacts of land-use change are globally interconnected and spill over to distant locations; 6) humanity lives on a used planet where all land provides benefits to societies; 7) land-use change usually entails trade-offs between different benefits-"win-wins" are thus rare; 8) land tenure and land-use claims are often unclear, overlapping, and contested; 9) the benefits and burdens from land are unequally distributed; and 10) land users have multiple, sometimes conflicting, ideas of what social and environmental justice entails. The facts have implications for governance, but do not provide fixed answers. Instead they constitute a set of core principles which can guide scientists, policy makers, and practitioners toward meeting sustainability challenges in land use.


Asunto(s)
Agricultura , Conservación de los Recursos Naturales/métodos , Ecosistema , Humanos , Energía Renovable , Cambio Social
4.
Pharmacol Res ; 200: 107046, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38159783

RESUMEN

In the current article the aims for a constructive way forward in Drug-Induced Liver Injury (DILI) are to highlight the most important priorities in research and clinical science, therefore supporting a more informed, focused, and better funded future for European DILI research. This Roadmap aims to identify key challenges, define a shared vision across all stakeholders for the opportunities to overcome these challenges and propose a high-quality research program to achieve progress on the prediction, prevention, diagnosis and management of this condition and impact on healthcare practice in the field of DILI. This will involve 1. Creation of a database encompassing optimised case report form for prospectively identified DILI cases with well-characterised controls with competing diagnoses, biological samples, and imaging data; 2. Establishing of preclinical models to improve the assessment and prediction of hepatotoxicity in humans to guide future drug safety testing; 3. Emphasis on implementation science and 4. Enhanced collaboration between drug-developers, clinicians and regulatory scientists. This proposed operational framework will advance DILI research and may bring together basic, applied, translational and clinical research in DILI.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Europa (Continente) , Predicción , Bases de Datos Factuales
5.
Phys Rev Lett ; 130(9): 091801, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36930908

RESUMEN

The SNO+ Collaboration reports the first evidence of reactor antineutrinos in a Cherenkov detector. The nearest nuclear reactors are located 240 km away in Ontario, Canada. This analysis uses events with energies lower than in any previous analysis with a large water Cherenkov detector. Two analytical methods are used to distinguish reactor antineutrinos from background events in 190 days of data and yield consistent evidence for antineutrinos with a combined significance of 3.5σ.

6.
Bioscience ; 70(4): 297-314, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32284630

RESUMEN

The Earth's population will become more than 80% urban during this century. This threshold is often regarded as sufficient justification for pursuing urban ecology. However, pursuit has primarily focused on building empirical richness, and urban ecology theory is rarely discussed. The Baltimore Ecosystem Study (BES) has been grounded in theory since its inception and its two decades of data collection have stimulated progress toward comprehensive urban theory. Emerging urban ecology theory integrates biology, physical sciences, social sciences, and urban design, probes interdisciplinary frontiers while being founded on textbook disciplinary theories, and accommodates surprising empirical results. Theoretical growth in urban ecology has relied on refined frameworks, increased disciplinary scope, and longevity of interdisciplinary interactions. We describe the theories used by BES initially, and trace ongoing theoretical development that increasingly reflects the hybrid biological-physical-social nature of the Baltimore ecosystem. The specific mix of theories used in Baltimore likely will require modification when applied to other urban areas, but the developmental process, and the key results, will continue to benefit other urban social-ecological research projects.

7.
Psychol Med ; 49(7): 1166-1173, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30221610

RESUMEN

BACKGROUND: Most studies underline the contribution of heritable factors for psychiatric disorders. However, heritability estimates depend on the population under study, diagnostic instruments, and study designs that each has its inherent assumptions, strengths, and biases. We aim to test the homogeneity in heritability estimates between two powerful, and state of the art study designs for eight psychiatric disorders. METHODS: We assessed heritability based on data of Swedish siblings (N = 4 408 646 full and maternal half-siblings), and based on summary data of eight samples with measured genotypes (N = 125 533 cases and 208 215 controls). All data were based on standard diagnostic criteria. Eight psychiatric disorders were studied: (1) alcohol dependence (AD), (2) anorexia nervosa, (3) attention deficit/hyperactivity disorder (ADHD), (4) autism spectrum disorder, (5) bipolar disorder, (6) major depressive disorder, (7) obsessive-compulsive disorder (OCD), and (8) schizophrenia. RESULTS: Heritability estimates from sibling data varied from 0.30 for Major Depression to 0.80 for ADHD. The estimates based on the measured genotypes were lower, ranging from 0.10 for AD to 0.28 for OCD, but were significant, and correlated positively (0.19) with national sibling-based estimates. When removing OCD from the data the correlation increased to 0.50. CONCLUSIONS: Given the unique character of each study design, the convergent findings for these eight psychiatric conditions suggest that heritability estimates are robust across different methods. The findings also highlight large differences in genetic and environmental influences between psychiatric disorders, providing future directions for etiological psychiatric research.


Asunto(s)
Familia/psicología , Trastornos Mentales/genética , Trastornos Mentales/psicología , Hermanos/psicología , Adulto , Alcoholismo/genética , Alcoholismo/psicología , Anorexia Nerviosa/genética , Anorexia Nerviosa/psicología , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno por Déficit de Atención con Hiperactividad/psicología , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/psicología , Trastorno Bipolar/genética , Trastorno Bipolar/psicología , Estudios de Casos y Controles , Estudios de Cohortes , Trastorno Depresivo Mayor/genética , Trastorno Depresivo Mayor/psicología , Femenino , Interacción Gen-Ambiente , Genotipo , Humanos , Masculino , Trastorno Obsesivo Compulsivo/genética , Trastorno Obsesivo Compulsivo/psicología , Carácter Cuantitativo Heredable , Esquizofrenia/genética , Psicología del Esquizofrénico , Suecia
8.
Mol Psychiatry ; 23(1): 6-14, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28924187

RESUMEN

The Integrative Psychiatric Research (iPSYCH) consortium has established a large Danish population-based Case-Cohort sample (iPSYCH2012) aimed at unravelling the genetic and environmental architecture of severe mental disorders. The iPSYCH2012 sample is nested within the entire Danish population born between 1981 and 2005, including 1 472 762 persons. This paper introduces the iPSYCH2012 sample and outlines key future research directions. Cases were identified as persons with schizophrenia (N=3540), autism (N=16 146), attention-deficit/hyperactivity disorder (N=18 726) and affective disorder (N=26 380), of which 1928 had bipolar affective disorder. Controls were randomly sampled individuals (N=30 000). Within the sample of 86 189 individuals, a total of 57 377 individuals had at least one major mental disorder. DNA was extracted from the neonatal dried blood spot samples obtained from the Danish Neonatal Screening Biobank and genotyped using the Illumina PsychChip. Genotyping was successful for 90% of the sample. The assessments of exome sequencing, methylation profiling, metabolome profiling, vitamin-D, inflammatory and neurotrophic factors are in progress. For each individual, the iPSYCH2012 sample also includes longitudinal information on health, prescribed medicine, social and socioeconomic information, and analogous information among relatives. To the best of our knowledge, the iPSYCH2012 sample is the largest and most comprehensive data source for the combined study of genetic and environmental aetiologies of severe mental disorders.


Asunto(s)
Ambiente , Predisposición Genética a la Enfermedad/genética , Trastornos Mentales/epidemiología , Trastornos Mentales/genética , Adolescente , Adulto , Factores de Edad , Niño , Estudios de Cohortes , Dinamarca , Femenino , Genotipo , Humanos , Masculino , Trastornos Mentales/clasificación , Trastornos Mentales/diagnóstico , Escalas de Valoración Psiquiátrica , Índice de Severidad de la Enfermedad , Adulto Joven
9.
Mol Psychiatry ; 23(2): 263-270, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28044064

RESUMEN

Difficulties in social communication are part of the phenotypic overlap between autism spectrum disorders (ASD) and schizophrenia. Both conditions follow, however, distinct developmental patterns. Symptoms of ASD typically occur during early childhood, whereas most symptoms characteristic of schizophrenia do not appear before early adulthood. We investigated whether overlap in common genetic influences between these clinical conditions and impairments in social communication depends on the developmental stage of the assessed trait. Social communication difficulties were measured in typically-developing youth (Avon Longitudinal Study of Parents and Children, N⩽5553, longitudinal assessments at 8, 11, 14 and 17 years) using the Social Communication Disorder Checklist. Data on clinical ASD (PGC-ASD: 5305 cases, 5305 pseudo-controls; iPSYCH-ASD: 7783 cases, 11 359 controls) and schizophrenia (PGC-SCZ2: 34 241 cases, 45 604 controls, 1235 trios) were either obtained through the Psychiatric Genomics Consortium (PGC) or the Danish iPSYCH project. Overlap in genetic influences between ASD and social communication difficulties during development decreased with age, both in the PGC-ASD and the iPSYCH-ASD sample. Genetic overlap between schizophrenia and social communication difficulties, by contrast, persisted across age, as observed within two independent PGC-SCZ2 subsamples, and showed an increase in magnitude for traits assessed during later adolescence. ASD- and schizophrenia-related polygenic effects were unrelated to each other and changes in trait-disorder links reflect the heterogeneity of genetic factors influencing social communication difficulties during childhood versus later adolescence. Thus, both clinical ASD and schizophrenia share some genetic influences with impairments in social communication, but reveal distinct developmental profiles in their genetic links, consistent with the onset of clinical symptoms.


Asunto(s)
Trastorno del Espectro Autista/genética , Esquizofrenia/genética , Conducta Verbal/fisiología , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno del Espectro Autista/fisiopatología , Niño , Trastornos Generalizados del Desarrollo Infantil/genética , Comunicación , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Lenguaje , Estudios Longitudinales , Masculino , Herencia Multifactorial/genética , Factores de Riesgo , Esquizofrenia/fisiopatología , Conducta Social
10.
Mol Psychiatry ; 21(7): 969-74, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26324100

RESUMEN

Genomic risk profile scores (GRPSs) have been shown to predict case-control status of schizophrenia (SCZ), albeit with varying sensitivity and specificity. The extent to which this variability in prediction accuracy is related to differences in sampling strategies is unknown. Danish population-based registers and Neonatal Biobanks were used to identify two independent incident data sets (denoted target and replication) comprising together 1861 cases with SCZ and 1706 controls. A third data set was a German prevalent sample with diagnoses assigned to 1773 SCZ cases and 2161 controls based on clinical interviews. GRPSs were calculated based on the genome-wide association results from the largest SCZ meta-analysis yet conducted. As measures of genetic risk prediction, Nagelkerke pseudo-R(2) and variance explained on the liability scale were calculated. GRPS for SCZ showed positive correlations with the number of psychiatric admissions across all P-value thresholds in both the incident and prevalent samples. In permutation-based test, Nagelkerke pseudo-R(2) values derived from samples enriched for frequently admitted cases were found to be significantly higher than for the full data sets (Ptarget=0.017, Preplication=0.04). Oversampling of frequently admitted cases further resulted in a higher proportion of variance explained on the liability scale (improvementtarget= 50%; improvementreplication= 162%). GRPSs are significantly correlated with chronicity of SCZ. Oversampling of cases with a high number of admissions significantly increased the amount of variance in liability explained by GRPS. This suggests that at least part of the effect of common single-nucleotide polymorphisms is on the deteriorative course of illness.


Asunto(s)
Estudio de Asociación del Genoma Completo/métodos , Esquizofrenia/genética , Adulto , Estudios de Casos y Controles , Dinamarca , Femenino , Predisposición Genética a la Enfermedad/genética , Alemania , Humanos , Masculino , Herencia Multifactorial/genética , Polimorfismo de Nucleótido Simple/genética , Factores de Riesgo , Sensibilidad y Especificidad
11.
Acta Psychiatr Scand ; 136(1): 85-95, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28556887

RESUMEN

OBJECTIVE: Mesolimbic dopamine sensitization has been hypothesized to be a mediating factor of childhood adversity (CA) on schizophrenia risk. Activity of catechol-O-methyltransferase (COMT) Val158Met increases mesolimbic dopamine signaling and may be further regulated by methylenetetrahydrofolate reductase (MTHFR) C677T. This study investigates the three-way interaction between CA, COMT, and MTHFR. METHODS: We conducted a nested case-control study on individuals born after 1981, linking population-based registers to study the three-way interaction. We included 1699 schizophrenia cases and 1681 controls, and used conditional logistic regression to report incidence rate ratios (IRRs). RESULTS: Childhood adversity was robustly associated with schizophrenia. No main genetic effects were observed. MTHFR C677T increased schizophrenia risk in a dose-dependent manner per MTHFR T allele (P = 0.005) consequent upon CA exposure. After inclusion of the significant (P = 0.03) COMT × MTHFR × CA interaction, the risk was further increased per high-activity COMT Val allele. Hence, exposed COMT Val/Val and MTHFR T/T carriers had an IRR of 2.76 (95% CI, 1.66-4.61). Additional adjustments for ancestry and parental history of mental illness attenuated the results with the interaction being only marginally significant. CONCLUSION: MTHFR C677T and COMT Val158Met interact with CA to increase risk of schizophrenia.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles , Catecol O-Metiltransferasa/genética , Maltrato a los Niños , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Sistema de Registros , Esquizofrenia , Adolescente , Adulto , Adultos Sobrevivientes de Eventos Adversos Infantiles/estadística & datos numéricos , Estudios de Casos y Controles , Niño , Maltrato a los Niños/estadística & datos numéricos , Dinamarca/epidemiología , Femenino , Humanos , Masculino , Esquizofrenia/epidemiología , Esquizofrenia/etiología , Esquizofrenia/genética , Adulto Joven
12.
Proc Natl Acad Sci U S A ; 111(12): 4432-7, 2014 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-24616515

RESUMEN

Changes in land use, land cover, and land management present some of the greatest potential global environmental challenges of the 21st century. Urbanization, one of the principal drivers of these transformations, is commonly thought to be generating land changes that are increasingly similar. An implication of this multiscale homogenization hypothesis is that the ecosystem structure and function and human behaviors associated with urbanization should be more similar in certain kinds of urbanized locations across biogeophysical gradients than across urbanization gradients in places with similar biogeophysical characteristics. This paper introduces an analytical framework for testing this hypothesis, and applies the framework to the case of residential lawn care. This set of land management behaviors are often assumed--not demonstrated--to exhibit homogeneity. Multivariate analyses are conducted on telephone survey responses from a geographically stratified random sample of homeowners (n = 9,480), equally distributed across six US metropolitan areas. Two behaviors are examined: lawn fertilizing and irrigating. Limited support for strong homogenization is found at two scales (i.e., multi- and single-city; 2 of 36 cases), but significant support is found for homogenization at only one scale (22 cases) or at neither scale (12 cases). These results suggest that US lawn care behaviors are more differentiated in practice than in theory. Thus, even if the biophysical outcomes of urbanization are homogenizing, managing the associated sustainability implications may require a multiscale, differentiated approach because the underlying social practices appear relatively varied. The analytical approach introduced here should also be productive for other facets of urban-ecological homogenization.

13.
Environ Manage ; 58(2): 254-67, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27145945

RESUMEN

Efforts to create more sustainable cities are evident in the proliferation of sustainability policies in cities worldwide. It has become widely proposed that the success of these urban sustainability initiatives will require city agencies to partner with, and even cede authority to, organizations from other sectors and levels of government. Yet the resulting collaborative networks are often poorly understood, and the study of large whole networks has been a challenge for researchers. We believe that a better understanding of citywide environmental governance networks can inform evaluations of their effectiveness, thus contributing to improved environmental management. Through two citywide surveys in Baltimore and Seattle, we collected data on the attributes of environmental stewardship organizations and their network relationships. We applied missing data treatment approaches and conducted social network and comparative analyses to examine (a) the organizational composition of the network, and (b) how information and knowledge are shared throughout the network. Findings revealed similarities in the number of actors and their distribution across sectors, but considerable variation in the types and locations of environmental stewardship activities, and in the number and distribution of network ties in the networks of each city. We discuss the results and potential implications of network research for urban sustainability governance.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Conducta Cooperativa , Agencias Gubernamentales , Urbanización/legislación & jurisprudencia , Baltimore , Ciudades , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/legislación & jurisprudencia , Toma de Decisiones , Política Ambiental , Humanos , Desarrollo de Programa , Apoyo Social , Urbanización/tendencias
14.
Mol Psychiatry ; 19(3): 325-33, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23358160

RESUMEN

Genetic and environmental components as well as their interaction contribute to the risk of schizophrenia, making it highly relevant to include environmental factors in genetic studies of schizophrenia. This study comprises genome-wide association (GWA) and follow-up analyses of all individuals born in Denmark since 1981 and diagnosed with schizophrenia as well as controls from the same birth cohort. Furthermore, we present the first genome-wide interaction survey of single nucleotide polymorphisms (SNPs) and maternal cytomegalovirus (CMV) infection. The GWA analysis included 888 cases and 882 controls, and the follow-up investigation of the top GWA results was performed in independent Danish (1396 cases and 1803 controls) and German-Dutch (1169 cases, 3714 controls) samples. The SNPs most strongly associated in the single-marker analysis of the combined Danish samples were rs4757144 in ARNTL (P=3.78 × 10(-6)) and rs8057927 in CDH13 (P=1.39 × 10(-5)). Both genes have previously been linked to schizophrenia or other psychiatric disorders. The strongest associated SNP in the combined analysis, including Danish and German-Dutch samples, was rs12922317 in RUNDC2A (P=9.04 × 10(-7)). A region-based analysis summarizing independent signals in segments of 100 kb identified a new region-based genome-wide significant locus overlapping the gene ZEB1 (P=7.0 × 10(-7)). This signal was replicated in the follow-up analysis (P=2.3 × 10(-2)). Significant interaction with maternal CMV infection was found for rs7902091 (P(SNP × CMV)=7.3 × 10(-7)) in CTNNA3, a gene not previously implicated in schizophrenia, stressing the importance of including environmental factors in genetic studies.


Asunto(s)
Factores de Transcripción ARNTL/genética , Cadherinas/genética , Infecciones por Citomegalovirus/complicaciones , Interacción Gen-Ambiente , Proteínas de Homeodominio/genética , Esquizofrenia/genética , Nexinas de Clasificación/genética , Factores de Transcripción/genética , alfa Catenina/genética , Estudios de Casos y Controles , Infecciones por Citomegalovirus/genética , Dinamarca , Femenino , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Alemania , Humanos , Exposición Materna , Polimorfismo de Nucleótido Simple/genética , Esquizofrenia/complicaciones , Población Blanca/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc
17.
Scand J Med Sci Sports ; 24(6): e483-490, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24646366

RESUMEN

Three studies were conducted to validate the Training Distress Scale (TDS), a 19-item measure of training-related distress and performance readiness. Study 1 was a randomized, controlled laboratory experiment in which a treatment group undertook daily interval training until a 25% decrement occurred in time-to-fatigue performance. Comparisons with a control group showed that TDS scores increased over time within the treatment group but not in the control group. Study 2 was a randomized, controlled field investigation in which performance capabilities and TDS responses were compared across a high-intensity interval training group and a control group that continued normal training. Running performance decreased significantly in the training group but not in the control group, and scores on the TDS mirrored those changes in performance capabilities. Study 3 examined the relationship between TDS scores obtained over a 2-week period before major swimming competitions and subsequent performance in those competitions. Significantly, better performance was observed for swimmers with low TDS scores compared with those with moderate or high TDS scores. These findings provide both laboratory and field evidence for the validity of the TDS as a measure of short-term training distress and performance readiness.


Asunto(s)
Rendimiento Atlético/psicología , Acondicionamiento Físico Humano/psicología , Autoinforme , Estrés Psicológico/diagnóstico , Adolescente , Adulto , Apetito , Atención , Niño , Fatiga/psicología , Femenino , Humanos , Masculino , Mialgia/psicología , Esfuerzo Físico , Estudios Prospectivos , Reproducibilidad de los Resultados , Carrera/fisiología , Carrera/psicología , Trastornos del Sueño-Vigilia/psicología , Natación/fisiología , Natación/psicología , Adulto Joven
18.
ScientificWorldJournal ; 2014: 276892, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25254233

RESUMEN

Slaking experiments were conducted of fragipan clods immersed in solutions of poultry manure, aerobically digested biosolid waste (ADB), fluidized bed combustion byproduct (FBC), D-H2O, CaCO3, NaF, Na-hexa-metaphosphate, and ryegrass root biomass. The fragipan clods were sampled from the Btx horizon of an Oxyaquic Fragiudalf in Kentucky. Wet sieving aggregate analysis showed significantly better fragmentation in the NaF, Na-hexa-metaphosphate, and ryegrass root solutions with a mean weight diameter range of 15.5-18.8 mm compared to the 44.2-47.9 mm of the poultry manure, ADB, and FBC treatments. Dissolved Si, Al, Fe, and Mn levels released in solution were ambiguous. The poor efficiency of the poultry manure, ADB, and FBC treatments was attributed to their high ionic strength, while the high efficiency of the NaF, Na-hexa-metaphosphate, and rye grass root solutions to their high sodium soluble ratio (SSR). A slaking mechanism is proposed suggesting that aqueous solutions with high SSR penetrate faster into the fragipan capillaries and generate the critical swelling pressure and shearing stress required to rupture the fragipan into several fragments. Additional fragmentation occurs in a followup stage during which potential Si, Al, Fe, and Mn binding agents may be released into solution. Field experiments testing these findings are in progress.


Asunto(s)
Lolium/química , Extractos Vegetales/química , Raíces de Plantas/química , Suelo/química , Animales , Biomasa , Carbonato de Calcio/química , Restauración y Remediación Ambiental/métodos , Concentración de Iones de Hidrógeno , Lolium/crecimiento & desarrollo , Lolium/metabolismo , Estiércol/análisis , Fosfatos/química , Aves de Corral , Fluoruro de Sodio/química , Soluciones/química , Factores de Tiempo , Agua/química
19.
Psychol Health Med ; 19(3): 335-43, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23796233

RESUMEN

PURPOSE: The moderating effect of exercise habit strength and specific habit processes within the theory of planned behavior (TPB) was tested in children. METHODS: Participants were primary school students (N = 380, mean age = 10.46 ± .52). The data were collected using self-report measures followed by one-mile run test performance. Data were analyzed using structural equation modeling. RESULTS: The findings revealed that 34, 57, and 9% of students could be classified as low, moderate, and high in PA, respectively. Path analysis for the overall model revealed significant path loadings (p = < .05), except for the attitude-intention path. Moderating effects results revealed that strong habit strength extinguished the effects of intention on PA. CONCLUSION: Habit strength has the potential to minimize the deliberate processes associated with intention to exercise, thereby increasing the probability of intention-behavior translation. For specific habit processes, only negative affect appears to moderate the relationships between the TPB variables.


Asunto(s)
Conducta Infantil/psicología , Ejercicio Físico/psicología , Hábitos , Niño , Estudios Transversales , Prueba de Esfuerzo/métodos , Femenino , Humanos , Intención , Malasia , Masculino , Teoría Psicológica
20.
Environ Manage ; 54(3): 402-19, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25034751

RESUMEN

Several social theories have been proposed to explain the uneven distribution of vegetation in urban residential areas: population density, social stratification, luxury effect, and ecology of prestige. We evaluate these theories using a combination of demographic and socio-economic predictors of vegetative cover on all residential lands in New York City. We use diverse data sources including the City's property database, time-series demographic and socio-economic data from the US Census, and land cover data from the University of Vermont's Spatial Analysis Lab (SAL). These data are analyzed using a multi-model inferential, spatial econometrics approach. We also examine the distribution of vegetation within distinct market categories using Claritas' Potential Rating Index for Zipcode Markets (PRIZM™) database. These categories can be disaggregated, corresponding to the four social theories. We compare the econometric and categorical results for validation. Models associated with ecology of prestige theory are more effective for predicting the distribution of vegetation. This suggests that private, residential patterns of vegetation, reflecting the consumption of environmentally relevant goods and services, are associated with different lifestyles and lifestages. Further, our spatial and temporal analyses suggest that there are significant spatial and temporal dependencies that have theoretical and methodological implications for understanding urban ecological systems. These findings may have policy implications. Decision makers may need to consider how to most effectively reach different social groups in terms of messages and messengers in order to advance land management practices and achieve urban sustainability.


Asunto(s)
Planificación de Ciudades , Ambiente , Clase Social , Árboles , Vivienda , Humanos , Modelos Teóricos , Ciudad de Nueva York , Densidad de Población , Grupos de Población
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