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1.
Science ; 291(5501): 125-8, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11141563

RESUMO

We assessed the impacts of anthropogenic threats on 93 protected areas in 22 tropical countries to test the hypothesis that parks are an effective means to protect tropical biodiversity. We found that the majority of parks are successful at stopping land clearing, and to a lesser degree effective at mitigating logging, hunting, fire, and grazing. Park effectiveness correlates with basic management activities such as enforcement, boundary demarcation, and direct compensation to local communities, suggesting that even modest increases in funding would directly increase the ability of parks to protect tropical biodiversity.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Clima Tropical , Inquéritos e Questionários
2.
Biochim Biophys Acta ; 381(1): 157-64, 1975 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-1111581

RESUMO

Normal human washed erythrocytes were incubated in autologous plasma with 32P for varying periods of time. 2,3-Bisphosphoglyceric acid the major organic phosphate ester of red cells, was first isolated and purified by anion-exchange chromatography; subsequently, the C-2Pi was selectively hydrolyzed by a molybdate-catalyzed reaction. The C-2-bound Pi of 2,3-P2-glyceric acid was found to have a significantly higher specific activity than C-3 Pi. Intramolecular equilibration was not reached until the 180-min incubation. No evidence of overhydrolysis or internal randomization by the molybdate reaction was noted which was confirmed following hydrolysis of double-label 2,3-P2-glyceric acid 32P C-2, 33P C-3.


Assuntos
Ácidos Difosfoglicéricos/metabolismo , Eritrócitos/metabolismo , Molibdênio , Ácidos Fosfóricos/metabolismo , Cromatografia , Humanos , Hidrólise , Marcação por Isótopo , Métodos , Radioisótopos de Fósforo , Fosfotransferases/sangue , Fatores de Tempo
3.
J Control Release ; 57(3): 233-47, 1999 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-9895411

RESUMO

Paraffin wax and aqueous paraffin emulsions can be used as controlled release carriers for insect sex pheromones for mating disruption of orchard pests. Paraffin can be applied at ambient temperature as an aqueous emulsion, adheres to tree bark or foliage, releases pheromone for an extended period of time, and will slowly erode from bark and biodegrade in soil. Pheromone emulsions can be applied with simple spray equipment. Pheromone release-rates from paraffin were measured in laboratory flow-cell experiments. Pheromone was trapped from an air stream with an adsorbent, eluted periodically, and quantified by gas chromatography. Pheromone release from paraffin was partition-controlled, providing a constant (zero-order) release rate. A typical paraffin emulsion consisted of 30% paraffin, 4% pheromone, 4% soy oil, 1% vitamin E, 2% emulsifier, and the balance water. Soy oil and vitamin E acted as volatility suppressants. A constant release of oriental fruit moth pheromone from paraffin emulsions was observed in the laboratory for more than 100 days at 27 degreesC, with release-rates ranging from 0.4 to 2 mg/day, depending on the concentration and surface area of the dried emulsion. The use of paraffin emulsions is a viable method for direct application of insect pheromones for mating disruption. Sprayable formulations can be designed to release insect pheromones to the environment at a rate necessary for insect control by mating disruption. At temperatures below 38 degreesC, zero-order release was observed. At 38 degreesC and higher, pheromone oxidation occurred. A partition-controlled release mechanism was supported by a zero-order pheromone release-rate, low air/wax partition coefficients, and pheromone solubility in paraffin.


Assuntos
Controle de Insetos , Mariposas/fisiologia , Parafina/química , Atrativos Sexuais/química , Ar/análise , Algoritmos , Animais , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Físico-Química , Emulsões , Cromatografia Gasosa-Espectrometria de Massas , Atrativos Sexuais/administração & dosagem , Temperatura
4.
Med Sci Sports Exerc ; 32(9): 1576-81, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10994907

RESUMO

UNLABELLED: Many studies have implicated elevated oxygen consumption (VO2) associated with aerobic exercise as contributing to oxidative stress. Only a few studies have investigated nonaerobic exercise and its relation to pro-oxidant and antioxidant activities. PURPOSE: The purpose of this study was to compare biomarkers of oxidative stress: lipid peroxidation, protein oxidation, and total antioxidants in blood after exhaustive aerobic (AE) and nonaerobic isometric exercise (IE). METHODS: Blood samples were collected from 12 subjects who performed a maximum AE and IE test and were analyzed for thiobarbituric acid (TBARS), carbonyls, lipid hydroperoxides (LH), and oxygen radical absorbance capacity (ORAC). RESULTS: VO2 increased 14-fold with AE compared with 2-fold with IE. Protein carbonyls increased 67% (P < 0.05) pre- to immediately and 1 h post-AE, and 12% pre- to immediately post-IE and returned to baseline 1 h post-IE. TBARS did not increase significantly with either treatment. LH increased 36% above rest during IE compared with 24% during AE (P < 0.05). ORAC increased 25% (P < 0.05) pre- to post-AE, compared with 9% (P < 0.05) pre- to post-IE. CONCLUSION: There was evidence of oxidative stress after both exhaustive aerobic and isometric exercise. Lipid hydroperoxides, protein carbonyls, and total antioxidants increased after both IE and AE. Due to the different metabolic demands of aerobic and isometric exercise, we can rule out a mass action effect of VO2 as the sole mechanism for exercise-induced oxidative stress.


Assuntos
Exercício Físico/fisiologia , Consumo de Oxigênio/fisiologia , Espécies Reativas de Oxigênio , Adulto , Feminino , Força da Mão , Humanos , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo
5.
J Health Soc Behav ; 33(2): 168-85, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1619264

RESUMO

In this case study, computer systems are explored as catalysts for new interactions between departments in health care organizations. Hypotheses investigated changes in the extent to which members of different departments (1) exchange information and (2) understand each other's work following implementation of an integrated medical information system. Analyses showed that communication-based forms of involvement in implementation (communicating with systems personnel and trainers, communicating about new ways to use the system, and receiving support from supervisors for doing so) were overwhelmingly more important than either general participation or computer use in predicting increases in interdepartmental interaction. Changes in tasks and roles also led to new, informal, face-to-face contacts to support computer system use, as well as greater administrative control over the organization as a whole. In addition, results of interviews and observations over the two-year study period illustrate the importance of work group identification in predicting changes accompanying computerization.


Assuntos
Agendamento de Consultas , Sistemas Computacionais , Sistemas de Informação Hospitalar/instrumentação , Computação em Informática Médica , Sistemas Computadorizados de Registros Médicos/instrumentação , Serviços de Saúde para Estudantes , Atitude Frente aos Computadores , Humanos , Estudos Longitudinais , Interface Usuário-Computador
6.
J Stud Alcohol ; 60(5): 622-31, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10487731

RESUMO

OBJECTIVE: To investigate the prospective influence of individual adolescents' sensation seeking tendency and the sensation seeking tendency of named peers on the use of alcohol and marijuana, controlling for a variety of interpersonal and attitudinal risk and protective factors. METHOD: Data were collected from a cohort of adolescents (N = 428; 60% female) at three points in time, starting in the eighth grade. Respondents provided information about sensation seeking, the positivity of family relations, attitudes toward alcohol and drug use, perceptions of their friends' use of alcohol and marijuana, perceptions of influence by their friends to use alcohol and marijuana, and their own use of alcohol and marijuana. In addition, they named up to three peers, whose sensation seeking and use data were integrated with respondents' data to allow for tests of hypotheses about peer clustering and substance use. RESULTS: Structural equation modeling analyses revealed direct effects of peers' sensation seeking on adolescents' own use of both marijuana and alcohol 2 years later. An unexpected finding was that the individual's own sensation seeking had indirect (not direct) effects on drug use 2 years later. CONCLUSIONS: These findings indicate the potential importance of sensation seeking as a characteristic on which adolescent peers cluster. Furthermore, the findings indicate that, beyond the influence of a variety of other risk factors, peer sensation seeking contributes to adolescents' substance use.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Fumar Maconha/psicologia , Modelos Psicológicos , Assunção de Riscos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Comportamento do Adolescente , Feminino , Humanos , Relações Interpessoais , Masculino , Grupo Associado
7.
Mil Med ; 161(10): 601-6, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8984421

RESUMO

Nearly 400 spouses of enlisted soldiers who had deployed to Somalia as part of Operation Restore Hope in late 1992 and early 1993 were surveyed in July/August 1993. Their reported post-deployment and retrospective pre-deployment marital satisfaction was predicted as a function of four potentially stressful events or conditions: experiencing a pregnancy during deployment, experiencing loneliness, experiencing the death of a close friend or relative, and/or having problems communicating with one's spouse. Pre-deployment marital stability was used as a control variable. Results from multivariate analyses of variance suggest that the effects of various difficulties during a brief deployment are less stressful, at least in terms of their impact on marital satisfaction, than is often assumed, even for marriages that might be considered "at risk" in terms of low marital stability.


Assuntos
Casamento/psicologia , Militares/psicologia , Estresse Psicológico , Adulto , Luto , Comunicação , Feminino , Humanos , Solidão/psicologia , Casamento/estatística & dados numéricos , Análise Multivariada , Gravidez/psicologia , Somália , Cônjuges/psicologia , Estados Unidos
9.
J Econ Entomol ; 67(4): 561-2, 1974 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4854192
10.
11.
Somatosens Res ; 3(2): 89-118, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2424067

RESUMO

Electrophysiological studies have described four major tactile areas in the rat cerebellar cortex. These areas are in crus I, crus II, the paramedian lobule (PML), and the uvula, and a major portion of each is related to the ipsilateral orofacial region. This study demonstrates that neurons in trigeminal nucleus oralis (Vo) that project to the orofacial portions of these four major tactile areas are localized in the dorsomedial (DM) subdivision of the nucleus. The distribution, light-microscopic morphology, and relative densities of trigeminocerebellar neurons within DM, retrogradely labeled with horseradish peroxidase (HRP) following injections into each of the four major tactile areas, were analyzed and compared as well as correlated with the myelo- and cytoarchitecture of DM observed in Nissl sections, 1-micron sections, and Golgi material. On the basis of myelo- and cytoarchitectonic as well as trigeminocerebellar connectional criteria, three portions of DM were identified: caudal DM (CDM), middle DM (MDM), and rostral DM (RDM). The greatest portion of DM is made up of MDM (1.3 mm long), which can be further subdivided into dorsal (MDMd) and ventral (MDMv) zones. CDM forms the caudal 800 microns of DM, while RDM makes up the rostral 280 microns of the subdivision. Longitudinally running deep axon bundles permeate CDM, MDMv, and RDM, but are conspicuously absent from MDMd. The majority of neurons found throughout CDM, MDMv, and RDM have medium-sized (15- to 30-microns) somata and can be divided into two types on the basis of their somatodendritic morphology. CDM, MDMv, and RDM also contain a small neuronal cell type (5- to 15-microns cell body) that is encountered less frequently than either one of the two types of medium-sized cells. A fourth type of neuron with a large (25- to 50-microns) fusiform- to pyramidal-shaped cell body is the least frequently observed neuronal cell type and is located principally in CDM and MDMv. MDMd contains a fifth type of neuron characterized by a small (5- to 15-microns) oval soma. Data from the retrograde HRP experiments show that all five of these neuronal cell types in their respective portions of DM project to one or more of the orofacial portions of the four major tactile areas of the cerebellar cortex. Many medium-sized neurons of both types in CDM, MDMv, and RDM project to crus I, crus II, and/or PML.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Mapeamento Encefálico , Córtex Cerebelar/anatomia & histologia , Neurônios Aferentes/classificação , Núcleos do Trigêmeo/anatomia & histologia , Animais , Axônios/classificação , Contagem de Células , Córtex Cerebelar/citologia , Córtex Cerebelar/fisiologia , Dendritos/classificação , Lateralidade Funcional/fisiologia , Masculino , Vias Neurais/anatomia & histologia , Ratos , Ratos Endogâmicos , Coloração e Rotulagem , Tato/fisiologia , Núcleos do Trigêmeo/citologia , Núcleos do Trigêmeo/fisiologia , Úvula/inervação
12.
J Chem Ecol ; 27(9): 1821-39, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11545373

RESUMO

Sexually mature virgin adult males of the green stink bug, Acrosternum hilare attracted sexually mature virgin adult females in laboratory bioassays using a vertical Y-tube. There was no indication that males attracted other males, or that females attracted either sex. These results suggested that A. hilare males produce a sex pheromone. Extracts of odors collected from sexually mature males contained compounds that were not present in extracts from females or sexually immature males. (4S)-Cis-(Z)-bisabolene epoxide ((4S)-cis-Z-BAE) was the major sex-specific component of the extract. The crude extract was attractive to female A. hilare, but when separated into four fractions, only the portion containing (4S)-cis-Z-BAE and the minor component (4S)-trans-Z-BAE was attractive to females. This fraction was as attractive as the crude extract, suggesting that the former contained all the pheromone components. Neither synthetic (4S)-cis-Z-BAE nor (4S)-trans-Z-BAE alone was attractive to females, but a 95:5 cis:trans blend, mimicing the ratio naturally produced by males, was attractive to females in Y-tube bioassays. Bioassays in a field cage showed that significantly more A. hilare females were attracted to cotton string lures treated with 1 mg of a 95:5 blend of (4S)-cis-Z-BAE and (4S)-trans-Z-BAE placed inside a bouquet of alfalfa than to an alfalfa bouquet containing a pentane-treated control. In field cage studies, attraction of females was greatest during the late afternoon and evening hours, and female A. hilare approached the synthetic pheromone source almost exclusively by walking.


Assuntos
Hemípteros/química , Hemípteros/fisiologia , Sesquiterpenos/farmacologia , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal , Animais , Bioensaio , Feminino , Masculino , Odorantes , Caminhada
13.
J Chem Ecol ; 28(9): 1797-818, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12449507

RESUMO

The male-produced sex pheromone of the red-shouldered stink bug, Thyanta pallidovirens (Stål) (Hemiptera: Pentatomidae) consists of a blend of methyl (E2,Z4,Z6)-decatrienoate (E2,Z4,Z6-10:COOMe), and the sesquiterpenes (+)-alpha-curcumene, (-)-zingiberene, and (-)-beta-sesquiphellandrene. In laboratory bioassays, sexually mature males attracted sexually mature females but not males, and females did not attract either sex. Extracts of volatiles collected from sexually mature males contained compounds not present in extracts from females or sexually immature males, and male-produced extract was attractive to females. Biological activity was lost when the extract was fractionated, indicating that the pheromone consisted of at least two components having different chemical properties. Individually, pheromone components were not attractive to females, but E2,Z4,Z6-10:COOMe in combination with at least one of the three male-produced sesquiterpenes was attractive. The presence of more than one sesquiterpene in the blend did not increase attraction, indicating redundancy in the pheromone signal. Male extract was as attractive as a blend reconstructed from synthesized compounds, indicating all biologically active components had been identified. In bioassays conducted at dusk in a 1- x 1- x 1-m screen field cage, females were attracted to synthetic pheromone lures. In field trials, adult female T pallidovirens were attracted to pheromone-baited traps in relatively low numbers. The profile of volatiles released by sexually mature males of a congeneric species, Thyanta accerra custator McAtee, was remarkably similar to that of male T. pallidovirens, with the exception that the former species produced (E)-2-decenal, a compound that was not found in T. pallidovirens extracts.


Assuntos
Hemípteros/química , Sesquiterpenos/química , Atrativos Sexuais/química , Animais , Cromatografia Gasosa , Ésteres/química , Ésteres/farmacologia , Feminino , Hemípteros/classificação , Hemípteros/fisiologia , Masculino , Odorantes , Sesquiterpenos/farmacologia , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal , Estereoisomerismo
14.
J Chem Ecol ; 7(4): 695-706, 1981 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24420684

RESUMO

Two components of the San Jose scale sex pheromone had previously been identified as 7-methyl-3-methylene-7-octen-1-yl propanoate (I) and (Z)-3,7-dimethyl-2,7-octadien-1-yl propanoate (II). An isomer and various homologs have subsequently been synthesized and tested in a greenhouse bioassay. TheE isomer of II (XI) was found to be attractive to male scales. This compound has now been isolated and identified from airborne extracts of virgin female scales. The composition of the natural pheromone was 48.5%, 46.7%, and 4.8% of I, II, and XI, respectively. In field tests in California and New York, synthetic XI was found to be attractive to male scales alone and in combination with I and II, but there was no obvious increase in trap catch when the synthetic isomers were present in the same ratio as in the natural blend.

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