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1.
Sensors (Basel) ; 23(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896648

RESUMO

This manuscript presents the Microwave Temperature and Humidity Profiler (MTHP), a dual-band spectroradiometer designed for measuring multi-incidence angle temperature and humidity atmospheric profiles from an aircraft platform. The MTHP bands are at 60 GHz for measuring the oxygen complex lines, therefore at this band, MTHP has a hyperspectral radiometer able to provide 2048 channels over an 8 GHz bandwidth, and 183 GHz for measuring water vapor, which only uses four channels since this absorption band's spectral richness is simpler. The MTHP builds upon the Microwave Temperature Profiler (MTP) with the inclusion of the hyperspectral radiometer. The instrument's design, components, and calibration methods are discussed in detail, with a focus on the three-point calibration scheme involving internal calibration loads and static air temperature readings. Preliminary results from the Technological Innovation into Iodine and GV aircraft Environmental Research (TI3GER) campaign are presented, showcasing the instrument's performance during flights across diverse geographical regions. The manuscript presents successful antenna temperature measurements at 60 GHz and 183 GHz. The hyperspectral measurements are compared with a simulated antenna temperature using the Atmospheric Radiative Transfer Simulator (ARTS) showing an agreement better than R2 > 0.88 for three of the flights analyzed. Additionally, the manuscript draws attention to potential Radio Frequency Interference (RFI) effects observed during a specific flight, underscoring the instrument's sensitivity to external interference. This is the first-ever airborne demonstration of a broadband and hyperspectral multi-incidence angle 60 GHz measurement. Future work on the MTHP could result in an improved spatial resolution of the atmospheric temperature vertical profile and, hence, help in estimating the Planetary Boundary Layer (PBL) with better accuracy. The MTHP and its hyperspectral multi-incidence angle at 60 GHz have the potential to be a valuable tool for investigating the PBL's role in atmospheric dynamics, offering insights into its impact on Earth's energy, water, and carbon cycles.

2.
Mitochondrion ; 73: 51-61, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37793469

RESUMO

INTRODUCTION: Stroke, the second leading cause of death worldwide, is a complex disease influenced by many risk factors among which we can find reactive oxygen species (ROS). Since mitochondria are the main producers of cellular ROS, nowadays studies are trying to elucidate the role of these organelles and its DNA (mtDNA) variation in stroke risk. The aim of the present study was to perform a comprehensive evaluation of the association between mtDNA mutations and mtDNA content and stroke risk. MATERIAL AND METHODS: Homoplasmic and heteroplasmic mutations of the mtDNA were analysed in a case-controls study using 110 S cases and their corresponding control individuals. Mitochondrial DNA copy number (mtDNA-CN) was analysed in 73 of those case-control pairs. RESULTS: Our results suggest that haplogroup V, specifically variants m.72C > T, m.4580G > A, m.15904C > T and m.16298 T > C have a protective role in relation to stroke risk. On the contrary, variants m.73A > G, m.11719G > A and m.14766C > T appear to be genetic risk factors for stroke. In this study, we found no statistically significant association between stroke risk and mitochondrial DNA copy number. CONCLUSIONS: These results demonstrate the possible role of mtDNA genetics on the pathogenesis of stroke, probably through alterations in mitochondrial ROS production.


Assuntos
DNA Mitocondrial , Acidente Vascular Cerebral , Humanos , DNA Mitocondrial/genética , Espécies Reativas de Oxigênio , Estudos de Casos e Controles , Predisposição Genética para Doença , Haplótipos , Mitocôndrias/genética , Acidente Vascular Cerebral/genética
3.
Chemosphere ; 325: 138360, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36905991

RESUMO

The environmental presence of micro/nanoplastics (MNPLs) is an environmental and human health concern. Such MNPLs can result from the physicochemical/biological degradation of plastic goods (secondary MNPLs) or can result from industrial production at that size, for different commercial purposes (primary MNPLs). Independently of their origin, the toxicological profile of MNPLs can be modulated by their size, as well as by the ability of cells/organisms to internalize them. To get more information on these topics we have determined the ability of three different sizes of polystyrene MNPLs (50, 200, and 500 nm) to produce different biological effects in three different human hematopoietic cell lines (Raji-B, THP-1, and TK6). Results show that none of the three sizes was able to induce toxicity (growth ability) in any of the tested cell types. Although transmission electron microscopy and confocal images showed cell internalization in all the cases, their quantification by flow cytometry demonstrated an important uptake by Raji-B and THP-1 cells, in comparison with TK6 cells. For the first ones, the uptake was negatively associated with the size. Interestingly, when the loss of mitochondrial membrane potential was determined, dose-related effects were observed for Raji-B and THP-1 cells, but not for TK6 cells. These effects were observed for the three different sizes. Finally, when oxidative stress induction was evaluated, no clear effects were observed for the different tested combinations. Our conclusion is that size, biological endpoint, and cell type are aspects modulating the toxicological profile of MNPLs.


Assuntos
Nanopartículas , Poliestirenos , Humanos , Poliestirenos/toxicidade , Microplásticos/toxicidade , Plásticos/toxicidade , Linhagem Celular , Nanopartículas/toxicidade
4.
Sci Rep ; 13(1): 3722, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36878988

RESUMO

The Soil Moisture Active Passive (SMAP) mission has dramatically benefited our knowledge of the Earth's surface processes. The SMAP mission was initially designed to provide complementary L-band measurements from a radiometer and a radar, producing geophysical measurements at a finer spatial resolution than the radiometer alone. Both instruments, sensitive to the geophysical parameters in the swath, provided independent measurements at different spatial resolutions. A few months after SMAP's launch, the radar transmitter's high-power amplifier suffered an anomaly, and the instrument could no longer return data. During recovery activities, the SMAP mission switched the radar receiver frequency facilitating the reception of Global Positioning System (GPS) signals scattered off the Earth's surface, and enabling the radar to become the first spaceborne polarimetric Global Navigation Satellite System - Reflectometry (GNSS-R) instrument. With more than 7 years of continued measurements, SMAP GNSS-R data are the most extensive existing GNSS-R dataset and the only one providing GNSS-R polarimetric measurements. We demonstrate that the SMAP polarimetric GNSS-R reflectivity, derived from Stokes parameters mathematical formulation, can enhance the radiometer data over dense vegetation areas, recovering some of the original SMAP radar capability to contribute to the science products and pioneering the first polarimetric GNSS-R mission.

5.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1449913

RESUMO

La información es el elemento básico de toda investigación científica, la cual requiere encontrar datos y tratarlos con la finalidad de obtener información agregada. Además, es necesario conocer el punto de vista de diversos autores que ya han abordado el tema de investigación. Por ello, los análisis bibliométricos han adquirido gran importancia en el ámbito científico. El presente trabajo tuvo como objetivo revisar en profundidad la literatura científica relacionada con el control de la gestión de las redes sanitarias, para identificar las publicaciones más relevantes, los autores más influyentes y las diferentes tendencias. Se trabajó con la base de datos Web of Science (WoS) para analizar 476 artículos, atendiendo a una serie de indicadores bibliométricos en un período de 51 años. Este estudio indica que la literatura científica de las redes sanitarias es un área de conocimiento en plena vigencia y actualidad, orientado principalmente al estudio teórico del análisis de redes; prevalece la metodología cuantitativa, mediante fuentes de información primaria; el idioma predominante es el inglés y solo se presentan recientes hallazgos relacionados con el estudio descriptivo del control de las redes sanitarias(AU)


Information is the basic element of all scientific research, which requires finding data and processing them in order to obtain aggregate information. In addition, it is necessary to know the point of view of various authors who have already addressed the research topic. Therefore, bibliometric analyses have acquired great importance in the scientific field. The present work aimed at reviewing in depth the scientific literature related to health network management control, in order to identify the most relevant publications, the most influential authors and the different trends. The Web of Science (WoS) database was used to analyze 476 articles, based on a series of bibliometric indicators over a period of 51 years. This study indicates that the scientific literature on health networks is an area of knowledge in full force and topicality, mainly oriented to the theoretical study of network analysis; the quantitative methodology prevails, through primary information sources; the predominant language is English and only recent findings related to the descriptive study of the control of health networks are presented(AU)


Assuntos
Humanos , Organização e Administração , Bibliometria , Sistemas Nacionais de Saúde
6.
Rev. med. Risaralda ; 25(1): 23-30, ene.-jun. 2019. tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1058567

RESUMO

Resumen Introducción: el desarrollo constante de estrategias locales de prevención, promoción, acciones curativas y de rehabilitación para personas con Accidente Cerebrovascular, permite reducir la letalidad, discapacidad y complicaciones. OBJETIVO: elaborar un Plan de Intervención Integral para la atención post hospitalaria de pacientes con Accidente Cerebrovascular en un Centro de Salud Familiar chileno. MÉTODOS: para diseñar el plan fue necesario elaborar un diagnóstico situacional, identificar los factores de riesgo, y caracterizar la población durante el periodo del 2009-2013. Luego junto a directivos, referentes técnicos y Equipo de Salud Cardiovascular se identificaron las estrategias de educación, cuidado y tratamiento que conformaron el plan. Resultados: entre un 40% a un 50% de las personas con Accidente Cerebrovascular presentan secuelas que requieren algún grado de apoyo, es por ello que el Plan de Intervención Integral integra diferentes profesionales de la salud, los que a través de terapias y técnicas colaboran para conseguir una situación funcional, familiar y social lo más próxima a la que el paciente tenía previo al accidente. CONCLUSIÓNES: un enfoque integral e interdisciplinario desde la atención primaria permite disminuir las complicaciones prevenibles, apoyar e integrar al paciente y a su familia en el proceso de tratamiento, disminuir el grado de discapacidad, optimizar los resultados funcionales y la reintegración social


Abstract Introduction: The constant development of local strategies for prevention, promotion, curative and rehabilitation actions for people with Vascular Brain Accident, can reduce lethality, disability and complications. Objective: to develop an Integral Intervention Plan for the post-hospital care of patients with Vascular Brain Accident in a Chilean Family Health Center. METHODS: to design the plan it was necessary to develop a situational diagnosis, identify the risk factors, and characterize the population during the period 2009-2013. Next, along with managers, technical referents and cardiovascular health team, the education, care and treatment strategies that shaped the plan were identified. Results: between 40% and 50% of people with Vascular Brain Accident have sequelae that require some degree of support, which is why the Integral Intervention Plan integrates different health professionals, who through therapies and techniques collaborate To achieve a functional, family and social situation as close as the patient had before the accident. CONCLUSIONS: a comprehensive and interdisciplinary approach from primary care allows reducing preventable complications, supporting and integrating the patient and his family in the treatment process, reducing the degree of disability, optimizing functional outcomes and social reintegration.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Fatores de Risco , Acidente Vascular Cerebral , Assistência Hospitalar , Atenção Primária à Saúde , Terapêutica , Estratégias de Saúde Locais , Saúde da Família , Estratégias de Saúde
7.
Rev. costarric. salud pública ; 28(1): 59-73, ene.-jun. 2019. tab
Artigo em Espanhol | LILACS | ID: biblio-1013976

RESUMO

Resumen Este artículo identifica y analiza la relación entre la sustentabilidad financiera y la excelencia de la atención hospitalaria de la salud pública chilena. Los datos se obtienen directamente del Cuadro de Mando Integral de los 57 hospitales chilenos de mayor complejidad. Se realiza un análisis univariado, para determinar el comportamiento tendencial de los indicadores que componen las estrategias de sustentabilidad financiera y excelencia de la atención; luego un análisis bivariado para establecer asociaciones entre indicadores y variables relevantes, y analizar el funcionamiento de los establecimientos; y finalmente un análisis multivariado, donde se utiliza la técnica de análisis factorial confirmatoria. Demuestra que existe una relación negativa entre los resultados de ambas estrategias en estudio, por lo que se concluye que mejoras en los resultados de la sustentabilidad financiera no se traducen directamente en los resultados de excelencia de la atención hospitalaria, ya que no existe una canalización efectiva entre ambas estrategias.


Abstract Objective: To determine. This article identifies and analyzes the relationship between financial sustainability and the excellence of hospital care in Chilean public health. The data is obtained directly from the Balanced Scorecard of the 57 most complex Chilean hospitals. A univariate analysis is carried out to determine the trend behavior of the indicators that make up the strategies of financial sustainability and excellence of care; then a bivariate analysis to establish associations between indicators and relevant variables, and analyze the operation of the establishments; and finally a multivariate analysis, where the technique of confirmatory factor analysis is used. It shows that there is a negative relationship between the results of both strategies under study, so it is concluded that improvements in the results of financial sustainability do not translate directly into the results of excellence in hospital care, since there is no effective channeling between both strategies.


Assuntos
Qualidade da Assistência à Saúde/organização & administração , Reforma dos Serviços de Saúde/economia , Indicadores de Desenvolvimento , Assistência Hospitalar/economia , Indicadores de Gestão/políticas , Chile , Saúde Pública
10.
J Abnorm Psychol ; 126(5): 635-651, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28425737

RESUMO

The longitudinal structure of depression in children and adolescents was examined by applying a Trait-State-Occasion structural equation model to 4 waves of self, teacher, peer, and parent reports in 2 age groups (9 to 13 and 13 to 16 years old). Analyses revealed that the depression latent variable consisted of 2 longitudinal factors: a time-invariant dimension that was completely stable over time and a time-varying dimension that was not perfectly stable over time. Different sources of information were differentially sensitive to these 2 dimensions. Among adolescents, self- and parent reports better reflected the time-invariant aspects. For children and adolescents, peer and teacher reports better reflected the time-varying aspects. Relatively high cross-informant agreement emerged for the time-invariant dimension in both children and adolescents. Cross-informant agreement for the time-varying dimension was high for adolescents but very low for children. Implications emerge for theoretical models of depression and for its measurement, especially when attempting to predict changes in depression in the context of longitudinal studies. (PsycINFO Database Record


Assuntos
Transtorno Depressivo/diagnóstico , Adolescente , Criança , Análise Fatorial , Docentes , Feminino , Humanos , Estudos Longitudinais , Masculino , Variações Dependentes do Observador , Pais , Índice de Gravidade de Doença , Fatores de Tempo
11.
PLoS One ; 12(2): e0171668, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28170441

RESUMO

Sonic hedgehog (Shh) is a morphogen essential to the developing nervous system that continues to play an important role in adult life by contributing to cell proliferation and differentiation, maintaining blood-brain barrier integrity, and being cytoprotective against oxidative and excitotoxic stress, all features of importance in amyotrophic lateral sclerosis (ALS). ALS is a fatal disease characterized by selective loss of motor neurons due to poorly understood mechanisms. Evidence indicates that Shh might play an important role in ALS, and that Shh signaling might be also adversely affected in ALS. Since little is known about the functional status of Shh pathway in patients with ALS, we therefore sought to determine whether Shh protein levels or biological activity in cerebrospinal fluid (CSF) was less in ALS patients than controls, and whether these measures could be correlated with ALS disease severity and disease progression, and with other CSF analytes of biological interest in ALS. Comparing Shh levels in the CSF of normal controls (n = 13), neurological controls (n = 12), and ALS patients (n = 9) measured by ELISA, we found that CSF Shh levels were not different between controls and ALS patients. However, when assessing Shh biological activity in CSF using in vitro cell-based assays, which measure Shh activity as inducible Gli-driven luminescence, we found that in the presence of exogenous recombinant Shh or the Shh agonist, purmorphamine, the inducible activity of CSF was significantly augmented in the control groups as expected, but not in the ALS group, suggesting the presence of an inhibitor of Shh signaling in ALS CSF samples. Since purmorphamine acts on Smoothened, downstream of Shh and its receptor Patched, the inhibitory action is downstream of Smoothened. Our results also demonstrated that while the inhibitory effect of ALS CSF on Shh signaling did not correlate significantly with ALS disease characteristics, the levels of IL-1ß and TNF-α did. In addition to being significantly elevated in ALS CSF, these cytokines negatively correlated with the disease duration, whereas GDF11 was a favorable predictor of ALS clinical score. We also found that TNF-α significantly inhibited Shh biological activity in vitro, potentially suggesting a novel role of TNF-α in ALS pathogenesis. Collectively, this is the first report demonstrating that Shh signaling in CSF of ALS patients is compromised.


Assuntos
Esclerose Amiotrófica Lateral/metabolismo , Proteínas Hedgehog/metabolismo , Adulto , Idoso , Esclerose Amiotrófica Lateral/líquido cefalorraquidiano , Esclerose Amiotrófica Lateral/diagnóstico , Estudos de Casos e Controles , Citocinas/líquido cefalorraquidiano , Citocinas/farmacologia , Progressão da Doença , Feminino , Proteínas Hedgehog/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Transdução de Sinais/efeitos dos fármacos
13.
Ann Bot ; 108(2): 263-77, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21712295

RESUMO

BACKGROUND AND AIMS: The geographic distribution of the genus Plectocephalus comprises a single species in Ethiopia, two in North America and possibly four more in South America, in a striking disjunction that is exceptional for genera of the tribe Cardueae. The enormity of this disjunction cast doubts on the precise taxonomic delineation of the genus, which is not unanimously recognized as a natural entity. The aims of this study were to define the generic boundaries of Plectocephalus and to formulate a hypothesis that would explain its natural range. METHODS: A combined molecular approach, using nuclear internal transcribed spacers (ITS) and external transcribed spacers (ETS), and plastid trnL-trnL-F, rpl32-trnL(UAG) and ndhF markers, was chosen for phylogenetic reconstruction by maximum parsimony and Bayesian inference. KEY RESULTS: Phylogenetic analysis shows that Plectocephalus is a natural genus that includes the African species P. varians, together with all the native South American species, currently classified as Centaurea, C. cachinalensis, C. floccosa and C. tweediei. The recognition of Centaurodendron as an independent genus, which we consider appropriate, would make Plectocephalus paraphyletic. Affinities of Plectocephalus should lie with eastern representatives of Centaureinae. Geographic disjunction is explained as a consequence of dispersal via the Bering Land Bridge during the Miocene--Pliocene. The phylogeny of the basal grade of Centaureinae differs from previous phylogenies, and artefacts resulting from differences in mutation rates of annual and perennial taxa are confirmed. Sensitivity of ITS to these differences was the highest observed for all DNA regions used in this study. CONCLUSIONS: The natural status of the genus Plectocephalus is confirmed and several nomenclatural combinations are proposed. New evidence contributes to the debate concerning problems posed by the use of ITS in the phylogenetic reconstruction of groups that differ in terms of their life cycles. Dispersal from Caucasus and Anatolia along the Siberian route and then across the Bering Land Bridge follows a route previously proposed for other taxonomic groups.


Assuntos
Asteraceae/genética , DNA Intergênico/genética , Evolução Molecular , Asteraceae/classificação , Centaurea/classificação , Centaurea/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Geografia , Filogenia , Análise de Sequência de DNA
14.
Muscle Nerve ; 42(5): 739-48, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20886510

RESUMO

Case reports and open-label studies suggest that coenzyme Q(10) (CoQ(10)) treatment may have beneficial effects in mitochondrial disease patients; however, controlled trials are warranted to clinically prove its effectiveness. Thirty patients with mitochondrial cytopathy received 1200 mg/day CoQ(10) for 60 days in a randomized, double-blind, cross-over trial. Blood lactate, urinary markers of oxidative stress, body composition, activities of daily living, quality of life, forearm handgrip strength and oxygen desaturation, cycle exercise cardiorespiratory variables, and brain metabolites were measured. CoQ(10) treatment attenuated the rise in lactate after cycle ergometry, increased (∽1.93 ml) VO(2)/kg lean mass after 5 minutes of cycling (P < 0.005), and decreased gray matter choline-containing compounds (P < 0.05). Sixty days of moderate- to high-dose CoQ(10) treatment had minor effects on cycle exercise aerobic capacity and post-exercise lactate but did not affect other clinically relevant variables such as strength or resting lactate.


Assuntos
Antioxidantes/uso terapêutico , Doenças Mitocondriais/tratamento farmacológico , Ubiquinona/análogos & derivados , Absorciometria de Fóton , Atividades Cotidianas , Adulto , Limiar Anaeróbio/efeitos dos fármacos , Antioxidantes/metabolismo , Composição Corporal/fisiologia , Química Encefálica/efeitos dos fármacos , Colina/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Feminino , Antebraço/fisiologia , Hemodinâmica/efeitos dos fármacos , Humanos , Contração Isométrica/fisiologia , Ácido Láctico/sangue , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fadiga Muscular/fisiologia , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Qualidade de Vida , Espectroscopia de Luz Próxima ao Infravermelho , Ubiquinona/sangue , Ubiquinona/uso terapêutico
15.
J Abnorm Child Psychol ; 31(5): 471-83, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14561056

RESUMO

Children with low (n = 25) and high (n = 38) peer-rated popularity completed an emotional Stroop task, using negative social words, a self-report measure of friendship value relative to other domains of competence, and the Child Depression Inventory (CDI). Six months later, they completed the CDI again. In regression analyses, after controlling for prior CDI scores, social status interacted significantly with both Stroop and value measures (separate regressions). For unpopular children, both greater friendship valuing and greater negative social word Stroop interference predicted increases in depressive symptoms. In contrast, neither predictor was significant for popular children. In a third regression that included friendship value and Stroop interference as joint predictors of depression change, their effects remained significant and independent. We discuss these findings' implications for 3 models of depression; Champion and Power's social-cognitive theory of depression (L. A. Champion and M. J. Power, 1995), Pyszczynski and Greenberg's self-regulatory perseveration theory of depression (T. Pyszczynski & J. Greenberg, 1992), and Harter's model of global self-worth (S. Harter, 1985).


Assuntos
Depressão/psicologia , Amigos , Grupo Associado , Desejabilidade Social , Criança , Cognição , Estudos de Coortes , Depressão/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Classe Social , Inquéritos e Questionários , Vocabulário
16.
J Pediatr Surg ; 38(5): 779-83, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12720193

RESUMO

BACKGROUND/PURPOSE: The current project is a preliminary qualitative exploration of changes in quality of life of patients who have undergone the Nuss Procedure. The current study explores quality of life after surgical repair from the perspectives of both the patients and the parent(s) of the younger participants. METHODS: This research constitutes the first segment in a mixed-method longitudinal design. The author conducted semistructured interviews based on the Keith and Schalock's quality of life model. Five youth who have undergone the Nuss Procedure and the parent(s) of the 4 younger participants were included in the study for a total of 10 participants. Textual analysis has been carried out using Atlas.ti, a qualitative data analysis program that facilitates such activities as selecting, coding, and comparing textual segments. RESULTS: Results based on these preliminary data indicate that the patients interviewed had significant improvement in overall quality of life, which they attributed to the surgery. Specific examples of patients' expressions of improved self-confidence and renewed interest in physical activity are given. CONCLUSIONS: The Nuss Procedure is a minimally invasive surgical option for correcting pectus excavatum deformities that may make important contributions to patients' self-perceptions and quality of life. The participants in the current study expressed satisfaction with both the physical results of the surgery and with how it improved their overall quality of life. The authors recommend further prospective longitudinal research that assesses pre- and postsurgery psychosocial status and the maintenance of perceived quality of life changes.


Assuntos
Tórax em Funil/psicologia , Tórax em Funil/cirurgia , Qualidade de Vida , Adolescente , Adulto , Criança , Humanos , Estudos Longitudinais , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos , Autoimagem , Inquéritos e Questionários , Procedimentos Cirúrgicos Torácicos
17.
J Abnorm Psychol ; 111(1): 156-65, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11866168

RESUMO

The authors address questions about the rate that depressive symptoms emerge, developmental and gender differences in this rate, and differences between parent and child estimates of this rate. In a 12-wave, cohort-sequential, longitudinal design, 1,570 children (Grades 4-11) and parents completed reports about children's depression. Cross-domain latent growth curve analysis revealed that (a) the rate of symptom growth varied with developmental level. (b) gender differences symptom growth preceded emergence of mean level gender differences, (c) the rate of symptom development varied with age, and (d) parent-child agreement about rate of symptom change was stronger than agreement about time-specific symptoms. The authors suggest that predictability of depressive symptoms varies with age and the dimension under investigation.


Assuntos
Depressão/epidemiologia , Adolescente , Criança , Depressão/diagnóstico , Depressão/psicologia , Feminino , Humanos , Incidência , Masculino
18.
Oecologia ; 61(3): 342-345, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28311060

RESUMO

Much more tannic acid or pin oak tannin is required to precipitate the abundant leaf protein, ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPC), from Manduca sexta gut fluid adjusted to pH 6.5 than is required to precipitate this protein from an aqueous buffer at the same pH. This finding demonstrates that some characteristic of M. sexta gut fluid, in addition to its basicity, counteracts the potential of tannins to precipitate ingested proteins. Gut fluid of M. sexta has a surface tension of 36-39 dynes/cm, indicating the presence of surfactants. Lysolecithin and linoleoylglycine, surfactants known to be present in insect gut fluids, also interfere with the precipitation of RuBPC by tannins at pH 6.5. It is concluded that detergency is a widespread property of insect gut fluids that counteracts the potential of tannins to precipitate die ary proteins, and it is argued that there is no longer any justification for continuing to refer to tannins as digestibility-reducing-substances. Finding that there has been no formidable barrier to the evolution of mechanisms that counter a generalized antidigestive action by tannins is difficult to reconcile with the idea that reduced digestibility is an evolved anti-herbivore adaptation of apparent plants.

19.
Oecologia ; 54(2): 205-211, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28311430

RESUMO

There is no correlation between protein-precipitating capacity and either total phenolic or proanthocyanidin content of extracts of mature foliage from six species of oaks: Quercus alba (white oak), Q. bicolor (swamp white oak), Q. macrocarpa (bur oak), Q. palustris (pin oak), Q. rubra (red oak), and Q. velutina (black oak). It is argued that studies which probe the role of tannins in the selection and utilization of food by herbivores should include a protein-precipitation assay, since such an assay provides a measure of the property of tannins which is presumed to contribute to their utility as defensive compounds. A convenient modification of the bovine serum albumin (BSA) precipitation assay, which measures the amount of protein precipitated when a plant extract is added to a BSA solution, is described. Advantages of this procedure recommend its routine adoption in studies of the role of tannins in plant-herbivore interactions.

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