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1.
Nature ; 571(7765): E8, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31249423

RESUMEN

In this Letter, a middle initial and additional affiliation have been added for author G. J. Nabuurs; two statements have been added to the Supplementary Acknowledgements; and a citation to the French National Institute has been added to the Methods; see accompanying Author Correction for further details.

2.
Nature ; 569(7756): 404-408, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31092941

RESUMEN

The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools1,2, sequester carbon3,4 and withstand the effects of climate change5,6. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems. Here we generate a spatially explicit global map of the symbiotic status of forests, using a database of over 1.1 million forest inventory plots that collectively contain over 28,000 tree species. Our analyses indicate that climate variables-in particular, climatically controlled variation in the rate of decomposition-are the primary drivers of the global distribution of major symbioses. We estimate that ectomycorrhizal trees, which represent only 2% of all plant species7, constitute approximately 60% of tree stems on Earth. Ectomycorrhizal symbiosis dominates forests in which seasonally cold and dry climates inhibit decomposition, and is the predominant form of symbiosis at high latitudes and elevation. By contrast, arbuscular mycorrhizal trees dominate in aseasonal, warm tropical forests, and occur with ectomycorrhizal trees in temperate biomes in which seasonally warm-and-wet climates enhance decomposition. Continental transitions between forests dominated by ectomycorrhizal or arbuscular mycorrhizal trees occur relatively abruptly along climate-driven decomposition gradients; these transitions are probably caused by positive feedback effects between plants and microorganisms. Symbiotic nitrogen fixers-which are insensitive to climatic controls on decomposition (compared with mycorrhizal fungi)-are most abundant in arid biomes with alkaline soils and high maximum temperatures. The climatically driven global symbiosis gradient that we document provides a spatially explicit quantitative understanding of microbial symbioses at the global scale, and demonstrates the critical role of microbial mutualisms in shaping the distribution of plant species.


Asunto(s)
Clima , Bosques , Mapeo Geográfico , Micorrizas/fisiología , Simbiosis , Árboles/metabolismo , Árboles/microbiología , Fijación del Nitrógeno , Lluvia , Estaciones del Año
3.
Ecol Lett ; 22(6): 936-945, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30884085

RESUMEN

Soil stores approximately twice as much carbon as the atmosphere and fluctuations in the size of the soil carbon pool directly influence climate conditions. We used the Nutrient Network global change experiment to examine how anthropogenic nutrient enrichment might influence grassland soil carbon storage at a global scale. In isolation, enrichment of nitrogen and phosphorous had minimal impacts on soil carbon storage. However, when these nutrients were added in combination with potassium and micronutrients, soil carbon stocks changed considerably, with an average increase of 0.04 KgCm-2  year-1 (standard deviation 0.18 KgCm-2  year-1 ). These effects did not correlate with changes in primary productivity, suggesting that soil carbon decomposition may have been restricted. Although nutrient enrichment caused soil carbon gains most dry, sandy regions, considerable absolute losses of soil carbon may occur in high-latitude regions that store the majority of the world's soil carbon. These mechanistic insights into the sensitivity of grassland carbon stocks to nutrient enrichment can facilitate biochemical modelling efforts to project carbon cycling under future climate scenarios.


Asunto(s)
Carbono , Suelo , Ecosistema , Nitrógeno , Nutrientes , Suelo/química
4.
Med J Armed Forces India ; 70(2): 100-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24843195

RESUMEN

BACKGROUND: Live donor liver transplant has become an accepted, effective and lifesaving alternative to deceased donor transplant. The effect on donor and his safety remains a cause of concern. The donors are all in productive age and in our setting may have to go back to active service. This study is aimed at knowing the results of donor hepatectomies at our centre. METHODS: Data of all donor hepatectomies done at our centre from Apr 2007 to Jun 2013 reviewed. This included the preoperative workup, operative details and postoperative follow-up. RESULTS: 35 Donors of age between 20 and 50 years were taken up for procedure of which one was abandoned due to haemodynamic instability after intubation. In the 34 procedures done the percentage of the residual liver was at least 30%. No donor required blood transfusion. The overall complication rate was 26.5% which was stratified according to the modified Clavien classification of postoperative complications. There was transient rise of bilirubin and liver enzymes in all which returned back to normal with time. Infections were the most common cause of complication. All the donors had gone back to their work after a mean of 42 days after surgery. All donors were willing to donate again if needed. CONCLUSION: Living donor liver transplant a widely practiced modality for end-stage liver disease. It is a safe procedure with good recovery and results. Our study shows that meticulous selection criteria and strict adherence to protocols leads to good outcome.

5.
Med J Armed Forces India ; 64(3): 284-5, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27408170
6.
J Pediatr Psychol ; 25(5): 347-51, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10880065

RESUMEN

OBJECTIVE: To determine the neurodevelopmental effects of perinatally acquired HIV infection on children of preschool age. METHODS: Participants included 40 children infected with HIV between the ages of three and five and an equal number of noninfected controls individually matched according to ethnicity, age, sex, and prenatal drug exposure. Participants were administered the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), upon which an analysis of subtest distribution was conducted. RESULTS: Whereas both groups evidenced mean IQ and subtest scores significantly below published norms, an effect for HIV group status was not found when a factor combining Performance IQ (PIQ) and Verbal IQ (VIQ) was analyzed. However, the group infected with HIV scored significantly lower than controls on the Block Design subtest. CONCLUSIONS: Gross cognitive deficits are not evident among preschool children infected with HIV relative to matched controls. However, this study does provides some evidence for more focal deficits. Further investigation with older children should be conducted.


Asunto(s)
Desarrollo Infantil , Infecciones por VIH/psicología , Inteligencia , Estudios de Casos y Controles , Preescolar , Femenino , Infecciones por VIH/transmisión , Humanos , Transmisión Vertical de Enfermedad Infecciosa , Masculino , Desempeño Psicomotor , Escalas de Wechsler
8.
J Clin Psychol ; 56(3): 275-86, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10726663

RESUMEN

This article begins with a retrospective review of the editorial written in 1945 by Frederick C. Thorne at the inauguration of his new publication, the Journal of Clinical Psychology. It first considers the predictions made by Thorne about the future of clinical psychology and which of these turned out to be accurate, partially accurate, or inaccurate. At the time, the editorial caused its author to be accused of anti-Semitism and thus got the journal off to a rather bad start, from which it may have recovered only recently. The article then moves on to consider the past, present, and future of the field of clinical psychology from a contemporary vantage-point.


Asunto(s)
Prejuicio , Psicología Clínica/historia , Psicología Clínica/tendencias , Sociedades Científicas/historia , Educación de Postgrado/historia , Educación de Postgrado/tendencias , Historia del Siglo XX , Humanos , Psicología Clínica/organización & administración , Edición/historia , Sociedades Científicas/organización & administración , Sociedades Científicas/tendencias , Estados Unidos , Universidades/historia , Universidades/tendencias
10.
J Clin Child Psychol ; 26(1): 15-23, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9118171

RESUMEN

Investigated the interplay of family support and peer modeling on adolescent alcohol, tobacco, and marijuana use and gang involvement within an ecosystemic model. The predominantly Hispanic sample of 236 eighth-grade students attended a public middle school in a high-density, impoverished Miami neighborhood, characterized by high rates of criminal activity, substance abuse, and other stressors, placing the adolescents at risk for negative developmental outcomes. The participants reported the level of perceived social support they received from family members and rates of drug use and gang, involvement for themselves and for peers. The results showed that family social support reduced the influence of deviant peers on some of the problem behaviors reported by these adolescents, specifically tobacco and marijuana use. Deviant peer modeling was strongly associated with levels of adolescent problem behavior for tobacco, alcohol and marijuana use and gang involvement.


Asunto(s)
Conducta del Adolescente/psicología , Familia/psicología , Hispánicos o Latinos , Grupo Paritario , Apoyo Social , Trastornos Relacionados con Sustancias/psicología , Adolescente , California/etnología , Niño , Femenino , Humanos , Masculino , Estados Unidos/etnología
11.
J Abnorm Child Psychol ; 25(1): 1-5, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9093894

RESUMEN

This issue, redesigned in a new format, marks the beginning of Volume 25, the beginning of the "silver anniversary" year of the Journal of Abnormal Child Psychology. Data were compiled from the first 24 volumes to study changes over time, and Pearson correlations were calculated to determine linear trends in the journal's development. The number of articles per volume has doubled, from about 25 to 50. In recent years the first authors of articles were more likely to be located outside the U.S. (up from about 5% to about 25%). Also, in recent years the first authors of articles were less likely to be affiliated with nonmedical school university departments and more likely to be affiliated with medical schools or research institutes. An introduction to this special 25th anniversary issue is provided.


Asunto(s)
Publicaciones Periódicas como Asunto/historia , Psicología Infantil/historia , Niño , Historia del Siglo XX , Humanos , Estados Unidos
12.
J Child Psychol Psychiatry ; 37(2): 221-4, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8682902

RESUMEN

Dysphoric mothers rated their preschool children as having more internalizing and externalizing behavior problems than children of nondysphoric mothers. Observers rated the dysphoric mothers as having more negative affect during play interactions, although their children's affect was not rated more negatively. The dysphoric mother-infant dyads were also rated as having a poorer quality interaction. These data suggest that mothers' chronic dysphoria (75% were chronically dysphoric) has a negative impact on the mothers' perceptions of their children as well as the mothers' and children's interaction behavior.


Asunto(s)
Preescolar , Bienestar Materno , Trastornos del Humor/psicología , Madres/psicología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Edad Materna , Trastornos del Humor/diagnóstico , Relaciones Madre-Hijo , Escalas de Valoración Psiquiátrica , Distribución Aleatoria
13.
J Clin Psychol Med Settings ; 3(4): 337-53, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24226844

RESUMEN

Subjects were 288 adolescents and adults with end-stage renal disease who were candidates for kidney transplantation, a group identified at risk for noncompliance. The purpose was to examine racial and ethnic variations in coping-variables that may underlie noncompliance and impact upon health outcome. Secondarily, the relationship between depression and particular styles of coping was investigated. Race/Ethnicity was divided into three categories: Black/Non-Hispanic, White/Non-Hispanic, and Hispanic. Coping and depression were assessed using the COPE and Beck Depression Inventory, respectively. Results indicated that Hispanic and Black subjects were more likely to use maladaptive styles of coping and less likely to use adaptive coping than were White subjects and that Black subjects reported more physical symptoms of depression. These findings point to possible mechanisms underlying the occurrence of noncompliance and resulting poorer health outcome for individuals of different racial and ethnic groups.

14.
Child Health Care ; 24(2): 119-31, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-10143002

RESUMEN

We compared interpersonal distance and coping among two groups of pre-school pediatric patients diagnosed with either HIV or cancer and a third group of healthy children. In comparison to the children with cancer, children with HIV indicated greater mother-child interpersonal distance--a finding that correlated with mothers' reports of social withdrawal. Other notable findings included increased father-child distance in the HIV population and mother-child discrepancies of perceived interpersonal distance. In addition, seven of the children with HIV indicated that the adults turn away--a finding that correlated with the children's knowledge of their illness. We also explored the possible role of protective communication in the pediatric HIV population.


Asunto(s)
Adaptación Psicológica , Infecciones por VIH/psicología , Relaciones Interpersonales , Neoplasias/psicología , Niño , Preescolar , Comunicación , Padre/psicología , Florida , Humanos , Madres/psicología
15.
J Dev Behav Pediatr ; 15(3 Suppl): S49-53, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8063919

RESUMEN

Coping strategies and communication of three groups of 20 preschool children and their parents were compared. One group was composed of children infected with the human immunodeficiency virus (HIV) who displayed clinical symptoms of the disease; the second group was composed of children diagnosed with cancer; and the third group was composed of healthy children. Results indicated that the parents of children with life-threatening illnesses reported greater degrees of wishful thinking than did control subjects. Furthermore, parents of children with HIV reported more wishful thinking than did parents of children with cancer. Finally, significantly more children with cancer were aware of their diagnosis than were children with HIV. The findings in this study suggest coping and communication difficulties for parents and children with HIV.


Asunto(s)
Adaptación Psicológica , Comunicación , Infecciones por VIH/psicología , Neoplasias/psicología , Niño , Preescolar , Enfermedad Crónica , Negación en Psicología , Femenino , Florida , Humanos , Masculino , Relaciones Padres-Hijo , Padres , Determinación de la Personalidad , Autoimagen , Revelación de la Verdad
16.
Child Health Care ; 22(1): 47-59, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-10125240

RESUMEN

We examined nurses' assumptions concerning children and analgesia that have been hypothesized to explain the differential medication of postoperative child and adult patients. One hundred fourteen nurses from various pediatric and adult inpatient units of a large, urban teaching hospital were included in the study. A questionnaire consisting of four vignettes describing two hypothetical postoperative situations involving a child and adult patient, questions concerning choice of analgesic and assessment of pain for the hypothetical patients, and questions concerning the nurses' assumptions about children and analgesia was distributed to each nurse. The findings illustrate a pattern of differential medication of hypothetical child relative to hypothetical adult postoperative patients. The belief that children feel less pain than adults and concern about respiratory depression were associated with nurses' analgesia decisions.


Asunto(s)
Analgésicos/administración & dosificación , Personal de Enfermería en Hospital/psicología , Dolor Postoperatorio/tratamiento farmacológico , Cuidados Posoperatorios/enfermería , Cuidados Posoperatorios/normas , Adulto , Analgésicos/efectos adversos , Niño , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Errores de Medicación , Personal de Enfermería en Hospital/normas , Personal de Enfermería en Hospital/estadística & datos numéricos , Encuestas y Cuestionarios , Estados Unidos
17.
J Pediatr Psychol ; 18(5): 575-91, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8295081

RESUMEN

Compared 25 preschool children with sickle cell disease (SCD) to demographically matched healthy comparison children on maternal reports of child-rearing beliefs and practices and maternal and child behaviors related to social adjustment. Mothers of children with SCD possessed significantly more knowledge of appropriate discipline techniques. The groups did not differ on maternal reports of socially relevant child behavior. However, when mother-child interactions were observed in free play and structured play settings, mothers of children with SCD treated their children as competent significantly more, and treated their children as incompetent significantly less, than comparison mothers. Mothers of children with SCD also used significantly more reinforcement during the final toy pick-up condition. There were no observed differences between groups in the children's behavior.


Asunto(s)
Anemia de Células Falciformes/psicología , Relaciones Madre-Hijo , Responsabilidad Parental/psicología , Rol del Enfermo , Anemia de Células Falciformes/genética , Preescolar , Femenino , Humanos , Masculino , Refuerzo en Psicología , Ajuste Social , Medio Social
18.
J Pediatr Psychol ; 18(5): 593-604, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8295082

RESUMEN

Manipulated experimentally mothers' verbal behavior during a routine intramuscular injection in order to help clarify the role of nonprocedural talk (distraction) and parental reassurance on children's reaction to the injection. 42 child-mother dyads were recruited from a general pediatric primary care clinic and were randomly assigned to a parental reassurance, parental nonprocedural talk (distraction) or minimal-treatment control group. Children in the maternal distraction condition exhibited significantly less distress during the immunization injection than those in the reassurance and control conditions. Specifically, children in the maternal distraction group exhibited less crying than children in the other two groups. Children in the reassurance and control groups did not differ from each other in terms of behavioral distress. The present findings serve further to bolster the evidence for the efficacy of maternal distraction as a way to ameliorate child distress during invasive medical procedures.


Asunto(s)
Adaptación Psicológica , Atención , Inyecciones/psicología , Grupos Minoritarios/psicología , Madres/psicología , Refuerzo en Psicología , Preescolar , Miedo , Femenino , Humanos , Masculino
19.
Child Abuse Negl ; 17(4): 477-85, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8402250

RESUMEN

Recalled abuse was examined in relation to dissociation in a sample of 312 undergraduates. The Physical Abuse Scale of the Assessing Environments III (Berger & Knutson, 1984) and a newly developed sexual abuse questionnaire measured recalled physical and sexual abuse. The Harvard Group Scale of Hypnotic Susceptibility (Shor & Orne, 1962), Tellegen Absorption Scale (Tellegen, 1982), and Dissociative Experiences Scale (Bernstein & Putnam, 1986) measured dissociation. Significant correlations were found between the abuse variables and the dissociation variables, for all the measures except the Harvard Group Scale. Prevalence of sexual abuse, but not physical abuse was found to be significantly higher for females than males.


Asunto(s)
Abuso Sexual Infantil/diagnóstico , Maltrato a los Niños/estadística & datos numéricos , Trastornos Disociativos/diagnóstico , Hipnosis , Recuerdo Mental , Adulto , Niño , Maltrato a los Niños/psicología , Abuso Sexual Infantil/psicología , Abuso Sexual Infantil/estadística & datos numéricos , Preescolar , Trastornos Disociativos/epidemiología , Trastornos Disociativos/psicología , Femenino , Humanos , Masculino , Pruebas de Personalidad , Prevalencia , Factores Sexuales
20.
J Pediatr Psychol ; 16(6): 717-26, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1798010

RESUMEN

Administered Zabin and Melamed's (1980) Child Development Questionnaire in their native languages to 20 Haitian, 20 Hispanic, 20 black American, and 20 white American mothers in a public hospital setting to inquire how they dealt with their children in various fearful situations. The white Americans were significantly more likely than black Americans or Haitians to report use of modeling and reassurance, whereas Haitians were less likely than the other groups to report use of these methods. Conversely, the Haitians were more likely than some of the other groups to report use of force in these situations. There were no significant differences in the groups' reported use of positive reinforcement or in reinforcement of dependency once two culturally inappropriate items were removed. The reported differences, especially those involving Haitians, were interpreted as reflecting historical and cultural trends.


Asunto(s)
Negro o Afroamericano/psicología , Comparación Transcultural , Miedo , Hispánicos o Latinos/psicología , Responsabilidad Parental/psicología , Adaptación Psicológica , Adulto , Niño , Crianza del Niño/psicología , Preescolar , Femenino , Haití/etnología , Humanos , Masculino
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