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1.
Nature ; 560(7716): E1, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29875404

RESUMO

In this Brief Communications Arising Reply, the affiliation for author P. H. Templer was incorrectly listed as 'Department of Ecology & Evolutionary Biology, University of California Irvine, Irvine, California 92697, USA' instead of 'Department of Biology, Boston University, Boston, Massachusetts 02215, USA'. This has been corrected online.

2.
Nature ; 540(7631): 104-108, 2016 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-27905442

RESUMO

The majority of the Earth's terrestrial carbon is stored in the soil. If anthropogenic warming stimulates the loss of this carbon to the atmosphere, it could drive further planetary warming. Despite evidence that warming enhances carbon fluxes to and from the soil, the net global balance between these responses remains uncertain. Here we present a comprehensive analysis of warming-induced changes in soil carbon stocks by assembling data from 49 field experiments located across North America, Europe and Asia. We find that the effects of warming are contingent on the size of the initial soil carbon stock, with considerable losses occurring in high-latitude areas. By extrapolating this empirical relationship to the global scale, we provide estimates of soil carbon sensitivity to warming that may help to constrain Earth system model projections. Our empirical relationship suggests that global soil carbon stocks in the upper soil horizons will fall by 30 ± 30 petagrams of carbon to 203 ± 161 petagrams of carbon under one degree of warming, depending on the rate at which the effects of warming are realized. Under the conservative assumption that the response of soil carbon to warming occurs within a year, a business-as-usual climate scenario would drive the loss of 55 ± 50 petagrams of carbon from the upper soil horizons by 2050. This value is around 12-17 per cent of the expected anthropogenic emissions over this period. Despite the considerable uncertainty in our estimates, the direction of the global soil carbon response is consistent across all scenarios. This provides strong empirical support for the idea that rising temperatures will stimulate the net loss of soil carbon to the atmosphere, driving a positive land carbon-climate feedback that could accelerate climate change.


Assuntos
Atmosfera/química , Ciclo do Carbono , Carbono/análise , Geografia , Aquecimento Global , Solo/química , Bases de Dados Factuais , Ecossistema , Retroalimentação , Modelos Estatísticos , Reprodutibilidade dos Testes , Temperatura
4.
Parasitol Res ; 97 Suppl 1: S107-S112, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16228265

RESUMO

Farmed mink (Mustela vison), a close relative of the domestic ferret (Mustela putorius furo), naturally infested with the squirrel flea (Ceratophyllus sciurorum) were included in a study to investigate three compounds for flea control. The test products were imidacloprid in a 10% (w/v) solution, an imidacloprid 10% (w/v)/permethrin 50% (w/v) solution, and phoxim; all three are well-known compounds for the control of different ectoparasites in a wide range of animals. Two groups of mink received 0.1 ml per animal of the imidacloprid or the imidacloprid/permethrin combination at days 0 and 28, respectively. Two groups of mink were sprayed with 25 ml of a 0.1% phoxim solution at day 0 and either 1x25 ml or 2x25 ml, respectively, of a 0.05% phoxim solution at day 28. One group of mink served as an untreated control. At assessment on day 56 the efficacy was 91.9% in the imidacloprid group, 89.3% in the imidacloprid/permethrin group, 92.2% in the phoxim 1x25-ml group and 99.3% in the phoxim 2x25 ml group, respectively. In the untreated control group an average of 757 fleas per mink nesting material was recorded.


Assuntos
Ectoparasitoses/veterinária , Furões/parasitologia , Imidazóis/uso terapêutico , Inseticidas/uso terapêutico , Nitrocompostos/uso terapêutico , Compostos Organotiofosforados/uso terapêutico , Permetrina/uso terapêutico , Administração Tópica , Animais , Quimioterapia Combinada , Ectoparasitoses/tratamento farmacológico , Imidazóis/administração & dosagem , Inseticidas/administração & dosagem , Vison/parasitologia , Neonicotinoides , Nitrocompostos/administração & dosagem , Permetrina/administração & dosagem , Sifonápteros
5.
J Inorg Biochem ; 64(3): 149-62, 1996 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-8893517

RESUMO

The binding of D-phenylalanine, D-Phe, to both zinc and cobalt carboxypeptidase A, ZnCPD and CoCPD, has been investigated by a combination of kinetic and spectroscopic techniques. Kinetic studies of the ZnCPD catalyzed hydrolysis of dansyl-Gly-Ala-L-Phe indicate that D-Phe inhibition occurs through a two-site sequential competitive inhibition mode with Ki values of 45 microM and 11.6 mM at pH 8.4, 1 M NaCl, 25 degrees C. Spectral titration of CoCPD under the same conditions indicates a very strong binding mode of D-Phe (KD < 100 microM) that only slightly perturbs the visible cobalt electronic transitions. However, the conversion of CoCPD.D-Phe into a CoCPD.D-Phe2 (KD, 1.13 mM) is accompanied by a very strong spectral perturbation resulting in a complex that is characterized by Amax values of 506 nm (epsilon = 27 M-1 cm-1) and 605 nm (epsilon = 17 M-1 cm-1) and a shoulder at 530 nm (epsilon = 23 M-1 cm-1). The spectral properties of this ternary complex differ markedly from that of the CoCPD.L-Phe.N3-ternary complex. X-ray absorption fine structure, XAFS, studies indicate that these differences are likely due to a more regular tetrahedral coordination sphere for the ternary azide complexes compared to an octahedral coordination geometry for the Zn and CoCPD.D-Phe2 complexes.


Assuntos
Carboxipeptidases/metabolismo , Cobalto/metabolismo , Fenilalanina/metabolismo , Zinco/metabolismo , Animais , Carboxipeptidases A , Bovinos , Cinética , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier
6.
J Soc Psychol ; 130(1): 77-80, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2325403

RESUMO

This study investigated the relationship of authoritarianism and attitudes toward AIDS victims in three samples. One hundred fifty-eight students at Oregon State University participated, including 101 students from the United States, 25 from Japan, and 32 from other Asian societies. The survey instrument included the 20-item Attitudes Toward AIDS Victims (ATAV) Scale, the 18-item F Scale, the Form A, and 14-item Formal Content of Dogmatism Scale. Results showed slight but significant correlations between the ATAV and F (r = .17, p less than .044) and Formal Content of Dogmatism (r = .20, p less than .023) Scales for the United States sample. Highly significant differences were found in the predicted direction among the three samples on authoritarianism, F = 43.94, p less than .001.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Atitude Frente a Saúde , Autoritarismo , Adulto , Asiático/psicologia , Comparação Transcultural , Feminino , Homossexualidade/psicologia , Humanos , Indonésia/etnologia , Japão/etnologia , Masculino , Oregon
7.
J Homosex ; 19(3): 103-16, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2212627

RESUMO

This study reports on the development of a Likert scale that measures attitudes toward AIDS victims (ATAV) in five phases. A total of 582 undergraduate (means age = 24.2) completed the survey forms, 249 males and 333 females. The results for Phase 1 yielded a scale with high part-whole correlations (.62-.90, p less than .001), corrected split-half reliability (.87, p less than .001), and alpha coefficients (.91, p less than .001). The following phases yielded significant correlations between the ATAV scale and attitudes toward homosexuals (.60, p less than .001), homosexual parenting (.64, p less than .001), other minority groups (.33, .37, p less than .001), capital punishment (-.27 p less than .001), and sexually liberal attitudes (.22, .37, .23, p, less than .025). Attitudes toward homosexuals are the central component in attitudes toward AIDS victims. A varimax rotated factor analysis of the ATAV yielded one primary factor accounting for 85.9% of the variance.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Atitude Frente a Saúde , Homossexualidade/psicologia , Comportamento Sexual , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Feminino , Humanos , Masculino , Inventário de Personalidade , Psicometria , Fatores de Risco , Isolamento Social
10.
J Sex Res ; 24(1): 299-304, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22375665
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