小学学习不良儿童对言语交际策略的理解与运用

[Abstract] Verbal communication strategy (VCS) refers to a programmed knowledge applied by individuals to understand and express intentions via language symbols in their realization of communicative objectives according to social conventions. As an important index of social development, verbal communication strategy has provided a new perspective for social skill studies. However, more work has to be done in the investigation of LD children’s VCS developmental pattern and affecting mechanism. Through contextual test, structured interview and role-play, the present study, by adopting integrated measurements of instrumental and interpersonal effectiveness, explored the developmental characteristics of Chinese learning-disabled primary school children across 3-6th grades at both comprehension and application levels. Then, their social perspective-taking performance and verbal retelling competence of each participant were examined, on the basis of which, path analysis was conducted, with social perspective-taking, verbal retelling and verbal communication strategy comprehension as independent variables, to reveal the inner mechanism affecting LD children’s application of verbal communication strategy. Finally, an intervention study was carried out through a combination of polite request strategy understanding lessons and social perspective-taking training dramas. The results indicate that:(1) No significant grade differences were found in LD group for polite request strategy, while significant differences were reported across different grades of non-LD children. For indirect reply strategy, significant grade and gender differences were found among LD children, but the developmental trajectory between the two groups was different. For both polite request and indirect reply strategies, the strategy comprehension level of LD children was significantly lower than those without learning disabilities. (2) No significant grade and gender differences were found in LD group in their application of polite request strategy, while for non-LD children, significant differences were reported across different grades. For indirect reply strategy, both LD and non-LD groups exhibited similar developmental characteristics. Significant group differences only exist in the over-all application level of polite request strategies, not in indirect reply strategies. However, the differences of the latter between the two groups were found at significant level only among the 11-12 year olds. (3) LD children’s perspective-taking and verbal retelling competence were significantly lower than those of non-LD group. For polite request strategy, the influence of social perspective-taking to strategy application was indirect and must be via strategy comprehension, while for indirect reply strategy, strategy comprehension was found to play as a partial mediator between social perspective-taking and strategy application. The influence of verbal retelling to strategy application was indirect on both types of strategies. (4) LD children’s strategy comprehension and social perspective-taking level can be improved, and the improvement of these two competences has significant positive impact on the increase of their strategy application level. Key Words: learning disabilities, verbal communication strategy, social perspective- taking

5-9岁儿童对常见食物及其功能的认知发展

Research on naïve biology investigates children spontaneous understanding of biology objects, phenomena and function. Previous researches focus mostly on biology phenomena. Little has done on organism’s function, such as eating food. Many research in this field found that children were unable to categorize food by nutrition criterion, but rely on physical cues. In order to investigate the development of children’s naïve understanding of food and to find if they can classify food by nutrition criterion, three age groups (5-year-olds, 7-year-olds, and 9-year-olds) were included in this study. Varies experimental tasks were also used to explore the children’s understanding of food and its function. The results showed as the followings: 1) A few 5-year- old children can classify food by nutrition criterion when they take the spontaneous classification task. However, more and more children can realize what make a kind of food different from another can be the nutrition it contains. 2) Kindergarteners can find the relation between food and its output. When they become older, more and more children can explain the relation by consistent theory. It can be said that 9-year-old children have already have a profound understanding of nutrition. They gradually developed naive theory of biology on nutrition level. 3) Even kindergarteners can understand the concept of “food balance”. However, with development there was a significant age increase in food balance choice. 4) Children’s knowledge of food balance grows with age, but urban and rural educational background influence cognitive performance.

社会形势预警的几种建模方法比较

Based on social survey data conducted by local research group in some counties executed in the nearly past five years in China, the author proposed and solved two kernel problems in the field of social situation forecasting: i) How can the attitudes’ data on individual level be integrated with social situation data on macrolevel; ii) How can the powers of forecasting models’ constructed by different statistic methods be compared? Five integrative statistics were applied to the research: 1) algorithm average (MEAN); 2) standard deviation (SD); 3) coefficient variability (CV); 4) mixed secondary moment (M2); 5) Tendency (TD). To solve the former problem, the five statistics were taken to synthesize the individual and mocrolevel data of social situations on the levels of counties’ regions, and form novel integrative datasets, from the basis of which, the latter problem was accomplished by the author: modeling methods such as Multiple Regression Analysis (MRA), Discriminant Analysis (DA) and Support Vector Machine (SVM) were used to construct several forecasting models. Meanwhile, on the dimensions of stepwise vs. enter, short-term vs. long-term forecasting and different integrative (statistic) models, meta-analysis and power analysis were taken to compare the predicting power of each model within and among modeling methods. Finally, it can be concluded from the research of the dissertation: 1) Exactly significant difference exists among different integrative (statistic) models, in which, tendency (TD) integrative models have the highest power, but coefficient variability (CV) ones have the lowest; 2) There is no significant difference of the power between stepwise and enter models as well as short-term and long-term forecasting models; 3) There is significant difference among models constructed by different methods, of which, support vector machine (SVM) has the highest statistic power. This research founded basis in all facets for exploring the optimal forecasting models of social situation’s more deeply, further more, it is the first time methods of meta-analysis and power analysis were immersed into the assessments of such forecasting models.

心理测验中项目表述效应的特点、机制和预测因素研究

心理测验中项目的表述效应是测量误差的一个重要来源。本研究借助焦虑控制问卷，探讨心理量表中项目表述效应的心理测量学特点和其产生的方法学上的原因。研究首先考察了项目表述效应在不同的群体间的交互效度验证；然后通过反转项目表述方向的方法，构造出原问卷项目的相反表达的项目，进而通过不同组合形成四个版本的问卷，经过量表层面和项目层面的分析，考查了项目表述效应的心理测量学特点。然后通过项目反应理论分析和实验研究，考查了项目反应理论产生的作用机制。研究最后还考查了人格因素对项目表述效应的影响。主要研究结果如下： 1． 焦虑控制问卷（ACQ）中项目表述效应稳定的存在，中文版问卷的主要结构是一个特质性因子，另外还有两个方法因子。这一结构很好的拟合了中国被试的数据，不管是单个量表验证的结果还是两组被试交互验证的结果都支持这一结构； 2． 通过反ACQ问卷，构造了四个版本的量表，对四个版本验证性因素分析的结果表明，全正向表述项目量表和全反向表述项目量表没有项目表述效应出现，而同时存在正向和反向表述项目的原文卷和反转问卷都出现了方法效应；正向项目和反向项目得分分析的结果表明，总分上只有原量表和全反向量表没有显著差异，原量表和全正量表与全反量表都有显著的差异，表明项目表述效应的出项只和反向表述项目的反向记分有关； 3． 基于项目层面的研究中，用Rasch模型中的Rating Scale Model和full information Bifactor item Analysis 分别去拟合数据，发现Rasch模型对数据的拟合不好，而Bifactor items Analysis 对数据的拟合稍好一些，说明焦虑控制问卷中的项目表述效应因子与特质因子确实不是在同一个水平上的因子，表述效应因子是次级因子； 4． 项目表述效应的产生机制是由于人们只对与自己特质水平最近的项目作是的反应，而对与自己实际特质水平较远的项目作否的反应模式特点造成的； 5． 关于人格对项目表述效应出现的预测作用研究表明，自尊、社会赞许性对反向表述效应因子的产生具有正向预测作用，而行为抑制、行为激活和负向评价恐惧对反向表述因子的出现具有负向的预测作用。 总而言之，本研究得出的结论是，项目表述效应是一种人为造成的方法效应，它是被试只对与自己特质水平最近的项目作是的反应，而对与自己实际特质水平较远的项目作否的反应模式特点造成的。但同时，它又不是完全没有意义的“讨厌”因子，一些人格因素可以预测它的出现，即它的出现受到一些人格因素的影响。

汶川地震后青少年创伤后应激障碍症状及其相关因素研究

The present paper studies focus on the symptoms of the post-traumatic stress disorder in adolescents post-disaster. 482 students from 6 secondary schools and 17 primary schools in the extremely severe disaster areas in Mianzhu, Sichuan province and 785 students from 3 primary schools and 9 secondary schools in the severe disaster areas in Baoji, Shaanxi respectively were surveyed on the symptoms of the post-traumatic stress disorder and the extent of disaster exposure after the Wenchuan earthquake. Self-compiled background information questionnaire and CRIES were used for the investigation. In this study, we contrast the extent of disaster exposure in the two areas in order to explore the related factors about the post-traumatic stress disorder in adolescent post-disaster. The main results of this paper can be summarized as follows： 1. There are significant positive corrections between the post-traumatic stress disorder and the extent of disaster exposure(get trapped in the earthquake、relatives and friends have been injured in the earthquake、look at relatives and friends dying in the earthquake).The more exposed in the disaster, the more serious symptom of the post-traumatic stress disorder. The trauma exposure indicators (get trapped in the earthquake, relatives and friends have been injured in the earthquake、look at relatives and friends dying in the earthquake)were all significant predictors for PTSD severity. 2. There are significant sex difference in the extent（F=8.750, p <0.05） and the incidence rate of PTSD（χ =20.735, df=5,p =0.001）, the extent and the incidence rate of girls in Mianzhu is significantly higher than that of boys. 3. The age is also an influence factor of PTSD. The extent （F=7.246, p <0.001）and the incidence rate （χ =20.735, df=5,p =0.001）of PTSD get higher as adolescent in Mianzhu get older. 4. As the extremely severe disaster areas, the extent of disaster exposure of Mianzhu areas significantly higher than that of the severe disaster areas Baoji. However, there are not difference in the extent of PTSD between two areas（t=0.181，df=1265,p=0.857）, there are only significant difference in the incidence rate of PTSD between two areas（χ =8.766，df=1,p=0.003）, the incidence rate of PTSD in Mianzhu areas significantly higher than that of Baoji areas.

中文MMPI与MMPI－2效度量表及临床量表的比较研究

This study is aimed at examining the degree of the basic scales (validity scales and clinical scales) between The Chinese MMPI and MMPI-2. Four samples (include schizophrenia, affective disorder, neuroses and normal subjects) of 236 subjects completed MMPI/MMPI-2 Combined Questionnaires in groups. The concordance rate for total code types was 90.1%. For 1-point, 2-point, 3-point and elevated code types, they were separately 81.6%, 65.8%, 49.2%, 64%. Only 56.8% of men compared to 73.8% of the women showed concordance in 2-ponit code types between MMPI and MMPI-2. And 58% of normal subjects compared to 48% of the schizophrenia subjects showed concordance in 3-point code types. Of the 236 cases, 156 (66.1%) had code types that were "well-defined" (1-, 2- or 3-point). 1-point, 2-point, 3-point well-defined code types respectively were 38.6%, 29.7%, 21.6%. For 2-point code types which were well-defined, the concordances was 84.3%, 82.8%, 85.7% (all the cases, men, women), higher than 64.4%, 56.8%, 72.9% when they were free-defined. 96.4% of subjects with incongruent 2-point code types had one of the scales in their MMPI code types with MMPI-2 code types. When deference caused by the use of uniform T-scores and new norms in MMPI-2 were found, the differences typically in code types congruence were not very great. Comparison of mean scores for the validity and clinical scales, 7 raw scores and 12 T-scores showed significant difference for MMPI versus MMPI-2 (Form). In spite of significant mean differences, correlational analyses show correlations above 0.92 for the raw scores and T-scores for each gender. All these results showed the good consistence between MMPI and MMPI-2 in basic scales, and showed MMPI-2 should be studied deeply.

Otimização de protocolo para análise de AFLP em Lolium multiflorum Lam.

ESTABELECIMENTO DE METODOLOGIA PARA ANÁLISE MOLECULAR DE AZEVÉM ANUAL COM MARCADORES AFLP. O uso de marcadores moleculares no manejo de bancos de germoplasma tem sido cada vez mais expressivo. Entre os diferentes tipos de marcadores moleculares, o AFLP, Amplified Fragment Length Polymorphism, apresenta algumas vantagens para uso na caracterização de recursos genéticos, como a detecção de grande número de bandas informativas por reação, com ampla cobertura do genoma e considerável reprodutibilidade, além de não necessitar de dados de seqüenciamento prévio da espécie para a construção de primers. Embora a análise de AFLP seja freqüentemente utilizada em estudos de variabilidade genética em diferentes espécies, o uso da técnica em Lolium multiflorum ainda é incipiente. Com a finalidade de estabelecer um protocolo para o emprego da técnica de AFLP em azevém anual foi conduzido este trabalho. Foram avaliadas as concentrações iniciais de DNA genômico de 100 e 250 ng, a digestão do DNA com 1,25 e 1U das enzimas EcoRI e MSe, e os respectivos tempos de reação de digestão: 3, 6 e 12 horas. Também foram avaliadas quatro concentrações da solução resultante da ligação dos adaptadores: solução sem diluição; diluída 1:5; 1:10 e 1:20 e duas diluições após a reação de pré-amplificação, de 1:25 e 1:50. Como resultado, foi estabelecido como melhor protocolo, no qual foi obtido um maior número e qualidade de fragmentos, o que utiliza a concentração inicial de DNA genômico de 100 ng, num volume final de reação de digestão 10 ?l, com 1U de cada enzima EcoRI e MseI e tempo de reação de 12h a 37°C, com reação de ligação de adaptadores realizada com a adição da solução de ligação de adaptadores, do Kit AFLP? Analysis System I (InvitroGen Life Technologies, Carlsbad, Calif., USA), e 0,4 U de T4 DNA ligase em um volume final de 10?l, por 2h a 20°C. Após a ligação de adaptadores a diluição deverá ser de 1:5. A reação de pré-amplificação deverá ocorrer a partir de 1?l desta última solução (diluída 1:5), 1,0 X PCR buffer com Mg Plus [Tris-HCl (pH 7.6) 20 mM, MgCl2 1,5 mM, KCl 50 mM], BSA 0,003% e 1 U de Taq DNA polimerase, completando com mix de pré-amplificação do Kit AFLP? Analysis System I até alcançar o volume final de 11?l. O produto da pré-amplificação deverá ser diluído 1:25 antes de ser procedida à amplificação seletiva, a qual deve ser realizada utilizando 2,5 ?l da solução de DNA pré-amplificado (diluído 1:25), 1 X PCR buffer com Mg Plus [Tris-HCl (pH 8,4) 20 mM, MgCl2 1,5 mM, KCl 50 mM], BSA (0,003%), 1 U de Taq DNA polimerase, 10 ng de primer EcoRI, 1,5 ng de primer MseI, 0,4mM de DNTps e H2O MilliQ? até completar o volume final de 10?l. Com este protocolo uma única combinação de primers permitiu identificar 58 bandas polimórficas na análise de duas populações de azevém anual.

Desempenho de clones de seringueira sob diferentes sistemas de sangria.

Este trabalho teve como objetivo avaliar o crescimento e a producao da borracha de clones seringueira [Havea brasiliensis ( Wild. Ex Adr. De Juss.) Muell. Arg.] sob diferentes sistemas de sangria, em condição de Cerrado dos Municipios de Barro Alto Goianesia no Estado de Goais. O plantio foi feito em fevereiro de 1992, no espacamento de 8,0 x 2,5 m (500 plantas/ha), em talhoes de 8 a 10 hectares para cada um dos clones RRIM 600, GT 1, PB 217, PB 235, PR 107 e PR 255 os quais receberam as mesmas praticas de manejo. Aos oito anos de idade, foram feitas as seguintes avaliacoes: estande final; circunferencia do caule a 1,20 m do solo; porcentagens de plantas aptas a sangria; producao de borracha acumulada na caneca pesada mensalmente; incidencia de seca de painel. A producao foi avaliada em nove sistemas de sangria em meia espiral (1/2 S), praticados cinco dias por semana (5d/7) e 10 meses ao ano (10m/12), variando na frequência de sangria (d/4 e d/7 = a cada 4 e 7 dias), a concentracao de Ethephon (ET 0,25%, 2,5%,3,3% e 5,0%) e sua frequencia de aplicacao durante o periodo chuvoso ( a cada 22, 28 e 35 dias), como segue: 1) 1/2S, d/7, ET 2,5% a cada 22 dias; 2)1/2S, d/7, ET 2,5% a cada 30 dias (referncia); 3) 1/2S. d/4, ET 2,5% a cada 30 dias; 4) 1/2S, d/7, ET 3,3% a cada 22 dias; 5)1/2S, d/7, ET 3,3% a cada 30 dias; 6) 1/2S. d/7, ET 5,0% a cada 22 dias 7) 1/2S, d/7, ET 5,0% a cada 30 dias; 8) 1/2S, d/7, ET 5,0% a cada 35 dias; 9) 1/2S, d/7, ET 0,25% (pulverizando 10 ml por painel) a cada 22 dias. Nos sistemas 1 a 8, o Ethephon foi pincelado ( 1mL) na canaleta de corte e ate 2 cm acima dela (Pa e La). O delineamento experimental foi de blocos ao acaso, com quatro repeticoes de 10 plantas poe parcela. Cada clone constitui um experimento separado, sendo os resultados de producao acumulada anual submetidos a analise de variancia e, nos caso de significancia, as medias dos sistemas foram comparadas pelo teste Tukey, ao nível de 5% de probabilidade. Nao foi constatada qualquer incidencia de seca de painel e os resultados possibilitaram as seguintes conclusoes para as condicoes da regiao: 1) o sistema 1/2S, d/7, ET 2,5% a cada 30 dias e o mais indicado par a sangria dos clones PR 255, PR 107, PB 235, PB 217 e GT 1; 2) o sistema 1/2S, d/7, ET 3,3% a cada 30 dias e o mais indicado para a sangria do clone RRIM 600; 3) a producao individual de borracha em kg/planta/ano e maior nos clones RRIM 600, PB 217 e PR 255, enquanto a producao total em kg/ha/ano e superior nos clones RRIM 600 e PB 235; 4)os clones PB 217 e PR 255 sao menos adaptados a regiao, apresentando menores valores de estande final, circunferencia do caule, porcentagem de plantas em sangria e de producao total de borracha por hectare.

Características agronômicas de bananeira Terra, cv. D'Angola, em consórcio com açaizeiro (Euterpe precatoria Mart.).

O sistema de cultivo em consórcio de fruteiras com outras culturas, sejam anuais, semiperenes ou perenes, constitui uma boa alternativa para propriedades rurais e uma importante forma de recuperação de áreas degradadas. O objetivo deste trabalho foi avaliar o comportamento de bananeira, cv. D'Angola, em monocultivo e consorciada com açaizeiro, Euterpe precatoria, em diferentes espaçamentos, no primeiro ciclo de produção. Para tanto, foi instalado um experimento seguindo um delineamento em blocos casualizados completos com quatro repetições e seis plantas por parcela. Os tratamentos foram: T1 ? bananeira em 3 m x 3 m (1.111 plantas ha-1); T2 ? bananeira em 3 m x 2 m (1.666 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T3 ? bananeira em 3 m x 3 m (1.111 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T4 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 6 m x 3 m (555 plantas ha-1) e T5 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 4 m x 2 m x 3 m (1.111 plantas ha-1). O sistema de cultivo da bananeira terra consorciada com açaizeiro em diferentes espaçamentos pode ser considerado como boa alternativa no primeiro ciclo, pois não apresentou interferência nas características de desenvolvimento, de produção e qualidade física dos frutos. Os plantios mais adensados propiciaram maiores produtividades no primeiro ciclo da cultura.

Suplementação com Vitamina D e seus derivados na prevenção e tratamento do cancro da próstata

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

Enhancing the health-status of processed meats through ingredient manipulation and its effects on sensory and physiochemical product attributes

An important component of this Ph.D. thesis was to determine the European consumers’ views on processed meats and bioactive compounds. Thus a survey gathered information form over 500 respondents and explored their perceptions on the healthiness and purchase-ability for both traditional and functional processed meats. This study found that the consumer was distrustful towards processed meat, especially high salt and fat content. Consumers were found to be very pro-bioactive compounds in yogurt style products but unsure of their feelings on the idea of them in meat based products, which is likely due to the lack of familiarity to these products. The work in this thesis also centred on the applied acceptable reduction of salt and fat in terms of consumer sensory analysis. The products chosen ranged in the degree of comminution, from a coarse beef patty to a more fine emulsion style breakfast sausage and frankfurter. A full factorial design was implemented which saw the production of twenty beef patties with varying concentrations of fat (30%, 40%, 50%, 60% w/w) and salt (0.5%, 0.75%, 1.0%, 1.25%, 1.5% w/w). Twenty eight sausage were also produced with varying concentrations of fat (22.5%, 27.5%, 32.5%, 37.5% w/w) and salt (0.8%, 1%, 1.2%, 1.4%, 1.6%, 2%, 2.4% w/w). Finally, twenty different frankfurters formulations were produced with varying concentrations of fat (10%, 15%, 20%, 25% w/w) and salt (1%, 1.5%, 2%, 2.5%, 3% w/w). From these products it was found that the most consumer acceptable beef patty was that containing 40% fat with a salt level of 1%. This is a 20% decrease in fat and a 50% decrease in salt levels when compared to commercial patty available in Ireland and the UK. For sausages, salt reduced products were rated by the consumers as paler in colour, more tender and with greater meat flavour than higher salt containing products. The sausages containing 1.4 % and 1.0 % salt were significantly (P<0.01) found to be more acceptable to consumers than other salt levels. Frankfurter salt levels below 1.5% were shown to have a negative effect on consumer acceptability, with 2.5% salt concentration being the most accepted (P<0.001) by consumers. Samples containing less fat and salt were found to be tougher, less juicy and had greater cooking losses. Thus salt perception is very important for consumer acceptability, but fat levels can be potentially reduced without significantly affecting overall acceptability. Overall it can be summarised that the consumer acceptability of salt and fat reduced processed meats depends very much on the product and generalisations cannot be assumed. The study of bio-actives in processed meat products found that the reduced salt/fat patties fortified with CoQ10 were rated as more acceptable than commercially available products for beef patties. The reduced fat and salt, as well as the CoQ10 fortified, sausages were found to compare quite well to their commercial counterparts for overall acceptability, whereas commercial frankfurters were found to be the more favoured in comparison to reduced fat and CoQ10 fortified Frankfurters.

Vitamin D status and requirements during pregnancy and lactation

Vitamin D deficiency during pregnancy, lactation, and early infancy has been widely reported. Current understanding of vitamin D metabolism during pregnancy and lactation is incomplete, and to date, experimental data to support vitamin D requirements for these life stages are scarce. There is a shortage of nationally representative data and appropriate reference ranges for serum 25-hydroxyvitamin D (25OHD) during pregnancy, lactation and infancy, including in umbilical cord blood. This thesis described concentrations of total 25OHD and individual metabolites including 25OHD3, 25OHD2, and 3-epi-25OHD3 at 15 weeks’ gestation in a large seasonally balanced pregnancy cohort study (n 1768), carried out in Cork, Ireland (52oN). The prevalence of low 25OHD concentrations in pregnant women was higher than published reports in other Caucasian women, and was highest among non-users of vitamin D-containing supplements during winter. A longitudinal pregnancy study was included which suggested gestational stages had an impact on the total serum 25OHD concentration. This thesis incorporated a randomized controlled trial carried out among 100 women across 3 intervention groups using 20 μg/day of vitamin D3 with or without 500 mg calcium, or placebo, over 12-weeks of lactation to investigate the vitamin D requirement for lactating mothers and the vitamin D content of human milk. A daily intake of 25 μg/day was suggested to meet the requirement of lactating women to maintain a 25OHD levels above 50 nmol/L in 97.5% of the population at 52oN all year around. However, vitamin D content in human milk did not increase in response to supplementation. Serum 25OHD concentration has been used as a predictor of a number of health outcomes. This thesis reported large differences in serum 25OHD concentrations using different methods in 86 umbilical cord samples. The need for international standardization of serum 25OHD measurements was re-emphasized in this thesis.

Hydraulic redistribution of soil water by roots affects whole-stand evapotranspiration and net ecosystem carbon exchange.

*Hydraulic redistribution (HR) of water via roots from moist to drier portions of the soil occurs in many ecosystems, potentially influencing both water use and carbon assimilation. *By measuring soil water content, sap flow and eddy covariance, we investigated the temporal variability of HR in a loblolly pine (Pinus taeda) plantation during months of normal and below-normal precipitation, and examined its effects on tree transpiration, ecosystem water use and carbon exchange. *The occurrence of HR was explained by courses of reverse flow through roots. As the drought progressed, HR maintained soil moisture above 0.15 cm(3) cm(-3) and increased transpiration by 30-50%. HR accounted for 15-25% of measured total site water depletion seasonally, peaking at 1.05 mm d(-1). The understory species depended on water redistributed by the deep-rooted overstory pine trees for their early summer water supply. Modeling carbon flux showed that in the absence of HR, gross ecosystem productivity and net ecosystem exchange could be reduced by 750 and 400 g C m(-2) yr(-1), respectively. *Hydraulic redistribution mitigated the effects of soil drying on understory and stand evapotranspiration and had important implications for net primary productivity by maintaining this whole ecosystem as a carbon sink.

Evaluación de terneza de reses de novillos Hereford bajo distintos modelos de invernada en el partido de Carlos Casares

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