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1.
Science ; 372(6545): 980-983, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34045354

RESUMO

Climate change and other human activities are causing profound effects on marine ecosystem productivity. We show that the breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts, with the strongest effects on fish-eating, surface-foraging species in the north. Hemispheric asymmetry suggests the need for ocean management at hemispheric scales. For the north, tactical, climate-based recovery plans for forage fish resources are needed to recover seabird breeding productivity. In the south, lower-magnitude change in seabird productivity presents opportunities for strategic management approaches such as large marine protected areas to sustain food webs and maintain predator productivity. Global monitoring of seabird productivity enables the detection of ecosystem change in remote regions and contributes to our understanding of marine climate impacts on ecosystems.

2.
Oecologia ; 190(1): 47-58, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30972488

RESUMO

Maternal and environmental effects can have profound effects on offspring performance by generating variation in offspring phenotypes, independent of genetic effects. Within avian broods, differential maternal investment of resources across the laying sequence is thought to be an adaptive strategy to modulate competitive hierarchies induced by hatching asynchrony. In this study, we evaluated the relative importance of maternally derived within-clutch variation and the asymmetric post-hatching environment for growth and survival of common tern (Sterna hirundo) siblings. We experimentally manipulated hatching order, resulting in chicks from last-laid eggs hatching first and vice versa. Although both initial age and size asymmetries were larger within experimental than control broods, the early survival of last-hatched chicks was similar between groups. Initial positive effects of egg size disappeared as siblings approached fledging. Ultimately at fledging, both within-brood growth and cumulative survival patterns were similar between experimental and control broods, suggesting that the effects of systematic variation of egg constituents (e.g., maternally derived yolk hormones) and egg size are too subtle and largely overwhelmed by the effects of hatching asynchrony. Therefore, we conclude that variation in offspring phenotypes is pre-dominantly determined by the social environment experienced post-hatching. Maternal effects may further fine-tune phenotypic variation in response to varying environmental conditions, but this needs to be tested through empirical studies in which multiple maternal effects are measured simultaneously under different environmental conditions.


Assuntos
Aves , Ovos , Animais , Humanos , Fenótipo , Irmãos
3.
Clin Genet ; 92(6): 632-638, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28646536

RESUMO

Cystinuria is a heterogeneous, rare but important cause of inherited kidney stone disease due to mutations in 2 genes: SLC3A1 and SLC7A9. Antenatal hyperechoic colon (HEC) has been reported in some patients as a non-pathological consequence of the intestinal transport defect. We report 83 patients affected by cystinuria: 44 presented prenatally with a HEC (HEC group) and 39 with a classical postnatal form (CC group). SLC3A1 and SLC7A9 were sequenced. All patients were fully genotyped, and the relationship between the genotype and clinical features was analyzed. We identified mutations in SLC3A1 in 80% of the HEC group and in only 49% of the CC group. The SLC3A1 p.Thr216Met mutation was found in 21% of the alleles in the HEC group but was never found in the CC group. Most of the mutations found in the HEC group were considered severe mutations in contrast with the CC group. Twenty-five novel mutations were reported. This study shows a relationship between genotype and the clinical form of cystinuria, suggesting that only the patients with the most severe mutations presented with an HEC. These results emphasized the need for prenatal cystinuria screening using classical third-trimester ultrasound scan and the early management of suspected newborns.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos/genética , Sistemas de Transporte de Aminoácidos Neutros/genética , Colo/diagnóstico por imagem , Cistinúria/diagnóstico por imagem , Cistinúria/genética , Mutação , Alelos , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Colo/metabolismo , Colo/patologia , Cistinúria/metabolismo , Cistinúria/patologia , Éxons , Feminino , Feto , Expressão Gênica , Estudos de Associação Genética , Genótipo , Humanos , Recém-Nascido , Íntrons , Fenótipo , Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia
4.
Int J Lab Hematol ; 38(1): 54-63, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26407903

RESUMO

INTRODUCTION: The automated XN-1000 hematology analyzer enables to perform a blood cell count and a leukocyte differential. When abnormal cells were detected, a flag was generated by the analyzer and a manual microscopic examination of the corresponding blood film was performed. METHODS: We compared the white blood cell differentials provided by the automated hematology analyzer XN-1000 in a pediatric population (n = 765) with those obtained through microscopic examination by cytologists and those obtained using a previous version of this analyzer, the XE-2100. Leukocytes count as well as flags sensitivity and specificity was analyzed. RESULTS: The leukocytes count provided by the analyzer is in good accordance with the differential obtained by manual count in children older than 3 months. The sensitivity for blast detection is 99% and the detection of reactive cells is 63%. The flag specificity remains low (<35%) for blood samples collected from infants between 8 days and 2 years of age, but increases up to 67% thereafter. The results obtained with the XN-1000 analyzer show an improvement in comparison with those obtained with the XE-2100 analyzer. CONCLUSION: The automated WBC differential provided by the XN-1000 analyzer in the pediatric setting is accurate, but a meticulous microscopic examination of blood smears remains necessary for infants up to 3 months of age to validate the analyzer flags.


Assuntos
Contagem de Leucócitos/métodos , Contagem de Leucócitos/normas , Leucócitos/citologia , Leucócitos/patologia , Adolescente , Automação Laboratorial , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Contagem de Leucócitos/instrumentação , Masculino , Microscopia/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Sci Total Environ ; 409(4): 710-8, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21145091

RESUMO

Wild birds are exposed to pollutants in their habitats. Top consumers of aquatic environments such as the fish-eating great cormorant (Phalacrocorax carbo sinensis) are especially affected due to the bioaccumulation of toxic substances in their tissues. This study analysed the livers of 80 great cormorants from Greece to estimate the concentration of organochlorines and mercury and to examine their possible toxic effects and origin. The results showed that mercury (geometric mean 8089 ng g⁻¹ dw), p,p'-DDE (2628 ng g⁻¹ dw), ∑HCHs (47 ng g⁻¹ dw) and HCB (116 ng g⁻¹ dw) concentrations can be considered high compared with those found in great cormorant livers elsewhere except in highly polluted areas, whereas ∑PCBs occurred in relatively low concentrations (1091 ng g⁻¹ dw). ß-HCH was the dominant HCH isomer. Pollutant levels were generally unrelated to area, age and gender. However, p,p'-DDE and p,p'-DDD showed intersite differences, whilst the proportion of PCBs with 8 chlorine atoms were significantly higher in adult than 1st year great cormorants. Pollution did not reflect local patterns but rather these along the Baltic and Black Seas, whilst differences in p,p'-DDE concentration and ∑DDTs/∑PCBs ratios between Evros, Axios or Amvrakikos, found on common migration route, suggested different bird origins. Most birds had toxic mercury concentrations; 83.7% above 4000 ng g⁻¹ dw and 16% above 17,000 ng g⁻¹ dw. Other pollutant levels were too low to have adverse effects.


Assuntos
Aves/metabolismo , Hidrocarbonetos Clorados/metabolismo , Fígado/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Fatores Etários , Animais , Monitoramento Ambiental , Mar Mediterrâneo , Praguicidas/metabolismo , Estações do Ano , Fatores Sexuais , Poluição Química da Água/estatística & dados numéricos
6.
J Anim Ecol ; 75(6): 1379-86, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17032370

RESUMO

1. The decomposition of population growth rate into contributions from different demographic rates has many applications, ranging from evolutionary biology to conservation and management. Demographic rates with low variance may be pivotal for population persistence, but variable rates can have a dramatic influence on population growth rate. 2. In this study, the mean and variance in population growth rate (lambda) is decomposed into contributions from different ages and demographic rates using prospective and retrospective matrix analyses for male and female components of an increasing common tern (Sterna hirundo) population. 3. Three main results emerged: (1) subadult return was highly influential in prospective and retrospective analyses; (2) different age-classes made different contributions to variation in lambda: older age classes consistently produced offspring whereas young adults performed well only in high quality years; and (3) demographic rate covariation explained a significant proportion of variation in both sexes. A large contribution to lambda did not imply a large contribution to its variation. 4. This decomposition strengthens the argument that the relationship between variation in demographic rates and variation in lambda is complex. Understanding this relationship and its consequences for population persistence and evolutionary change demands closer examination of the lives, and deaths, of the individuals within populations within species.


Assuntos
Envelhecimento/fisiologia , Charadriiformes/fisiologia , Caracteres Sexuais , Animais , Feminino , Masculino , Crescimento Demográfico , Fatores de Tempo
7.
Environ Pollut ; 108(2): 225-38, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-15092953

RESUMO

Between 1978 and 1996, egg and chick samples of little terns (Sterna albifrons) breeding at different colony sites along the eastern coast of Schleswig-Holstein, Germany, were annually gathered by chance in the framework of a long-term ringing programme. Analyses of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), hexachlorobenzene (HCB), hexachlorocyclohexane (HCHs), and mercury were carried out on eggs, chicks, and down (only mercury). In all matrices, pollutant concentrations decreased over the 19-year period. The mixture compositions of Sigma PCB, Sigma DDT, and Sigma HCH changed during the previous decades indicating decreasing releases of PCB mixtures, DDT, and technical HCH mixtures. The pollutant concentrations currently found in the tern eggs are compared with those of other bird species from other Baltic Sea subregions, suggesting a relatively low pollution of the Belt Sea. The temporal trends in contamination are related to international measurements and conventions on bans of pollutants. Since individually known females were recaptured up to three times, inter-individual variation in pollutant burdens could be studied. Remarkable variation among individuals as well as between breeding seasons were found that were not explainable by general temporal trends. Influences of individually and seasonally varying feeding habits on this phenomenon are discussed. Compositions of individual PCB mixtures varied in relation to total PCB concentrations found in eggs suggesting a concentration-dependent metabolization of PCBs as with other species. Amounts of particular organochlorines varied between matrices possibly indicating metabolization of low chlorinated PCBs, beta-HCH, and HCB during embryogenesis. In mercury, body detoxification via down is assumed. As indicated by eggshell parameters (thickness and index) being not related to organochlorine concentrations and being similar to that found in historical studies, respectively, effects of recent organochlorine contamination on eggshell thickness seem to be improbable. In conclusion, influences of contamination on declining little tern stocks observed in Germany are discussed. Negative influences of contamination in the 1960s and 1970s are assumed to be probable.

8.
Chemosphere ; 39(14): 2451-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10581697

RESUMO

Mercury concentrations were studied in blood, down and feathers of Common Gull (Larus canus L.) to investigate the suitability of bird blood as a matrix for biomonitoring of mercury in the marine environment. Chicks were collected in 1996 on the Elbe river and the Jade Bay. Like the side feathers, blood indicated site differences in mercury contamination. Correlational analyses showed that mercury concentrations in blood are significantly related to levels in side feathers (p < 0.001; Pearson), but not to those in down (p > 0.05; Pearson). Therefore, blood can be considered as a suitable matrix to indicate the current mercury burden in wild birds.


Assuntos
Aves/sangue , Monitoramento Ambiental/métodos , Mercúrio/sangue , Poluentes Químicos da Água/análise , Animais , Animais Selvagens
9.
Nurse Educ ; 22(4): 25-31, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9287718

RESUMO

To evaluate the education of undergraduate nursing students in drug administration, the faculty of La Salle University School of Nursing structured a program evaluation plan using a curriculum map. Faculty track the cognitive, affective, and psychomotor skills involved in drug administration. For example, all clinical nursing courses and the pharmacology course contain dosage and intravenous solution calculations in didactic material and tests. Program evaluation of the outcomes of medication administration education is continuous throughout the curriculum.


Assuntos
Currículo , Tratamento Farmacológico/enfermagem , Bacharelado em Enfermagem/organização & administração , Avaliação de Programas e Projetos de Saúde , Esquema de Medicação , Humanos , Pesquisa em Educação em Enfermagem
10.
Holist Nurs Pract ; 10(2): 57-68, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8550691

RESUMO

Grounded in teaching experiences with nursing students, Dewey's educational philosophy, principles of adult learning, and phenomenologic perspectives, the article presents a model of self-reflection discovered in the educational/learning process of caring for self. Self-reflection as a process is operationalized as a bending back of attention and a focus on self to uncover silence and meanings or essences of personal and professional experience. Critical outcomes of this process are increased awareness, increased depth and breadth of understanding, and expanded consciousness. The thesis that self-reflection is a critical process in caring for others is presented. The background for the work and the nursing course where students develop a clinical experience of caring for self are discussed. The article includes graphic representations of the reflective process and proposes that, through caring for self, transformation in caring experiences is possible.


Assuntos
Modelos de Enfermagem , Enfermeiras e Enfermeiros/psicologia , Autocuidado/psicologia , Pensamento , Adulto , Humanos , Pesquisa Metodológica em Enfermagem , Filosofia em Enfermagem , Psicologia Educacional
11.
Arch Environ Contam Toxicol ; 27(2): 162-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8060159

RESUMO

Eggs, feathers (down, body feathers from side/shoulder and back) and some dead chicks (liver) from broods of three species, herring full (Larus argentatus), black-headed gull (Larus ridibundus), and common tern (Sterna hirundo) from the German North Sea coast were collected to study intersibling differences in mercury contamination and elimination into the growing feathers. The mercury contamination in eggs, feathers, and liver of the terns was about four times that of the gulls; black-headed gulls had lowest mercury concentrations. The body feathers grow when the chicks became older had lower mercury levels than down in the more contaminated species (11% lower in herring gulls, 49% in common terns), indicating the advancing decontamination of the body by the plumage development. The elimination of mercury was greater in chicks with higher mercury levels. Down of the first hatched herring gull and common tern chick contained more mercury than down of the siblings hatched later, because of its higher burden derived from the first laid egg.


Assuntos
Aves/metabolismo , Carga Corporal (Radioterapia) , Plumas/metabolismo , Mercúrio/farmacocinética , Animais , Aves/embriologia , Aves/crescimento & desenvolvimento , Plumas/embriologia , Plumas/crescimento & desenvolvimento , Alemanha , Fígado/metabolismo , Mercúrio/análise
13.
Environ Pollut ; 80(3): 293-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-15091850

RESUMO

The relationships between mercury levels in eggs, tissues, and feathers of male and female herring gulls caught at their nests at a colony on the German Wadden Sea Coast were investigated, and an assessment of mercury intake and excretion of these birds was made. Samples of the liver, ovary, pectoral muscle, and body feathers, as well as the primary feather (in some cases), and eggs were taken from 37 adult herring gulls. Analysis of total mercury in all samples showed that body-feather and tissue levels were independent of sex. There was, however, a significant difference between levels of mercury in the primary feathers of male and female birds. Egg levels were not correlated to pectoral muscle, ovary, or feather levels although they were positively correlated with mercury levels in the liver. Liver levels were in turn correlated with mercury levels in the ovary. The ratio of mean feather to mean egg concentration ranged from 3.7 to 5.5 according to which feather was used. It was estimated that herring gulls from the Wadden coast ingested between 825 and 1337 microg of mercury in the year prior to analysis. It was also estimated that female birds may excrete over 20% more mercury via their eggs than could be excreted by male birds.

14.
Environ Pollut ; 79(3): 207-13, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-15091880

RESUMO

The hatching success of two Common Tern colonies, a highly contaminated one at the Elbe estuary (Hullen) and a less contaminated one at the Jade (Augustgroden, southern North Sea coast, Germany), was similar in 1988; 69% at Hullen and 73% at Augustgroden. Most egg loss was due to predators. The number of eggs failing to hatch from unknown causes was 6.3% higher at Hullen than at Augustgroden. Egg-shell thickness and strength were not correlated with the chemicals' concentrations. At Hullen unhatched eggs were compared with randomly collected fresh eggs; the former containing a significantly higher amount (20%) of PCBs (134 microg) than the eggs collected at random (112 microg). Seven out of 45 PCB-congeners were found in significantly higher amounts in the failed eggs, among them the toxic congener PCB 138. The two samples showed no difference in mercury concentration, which was 6.2 mg kg(-1), nor difference in shell strength. Eggs of Common Terns breeding at the Elbe estuary had concentrations of some contaminants reaching levels endangering breeding success.

15.
Ecotoxicology ; 2(1): 33-40, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24203117

RESUMO

: We studied mercury concentrations and amounts in tissues of 19 starved young Common Tern chicks (median age 4 days) and in eggs from the same colony. Concentrations and burden were similar between eggs and newly hatched chicks. Mercury concentrations were highest in down, which contained at least 38% of the body mercury. The mercury burden of the whole body and of the tissues as well as the concentration in down increased with age and body mass, indicating the importance of down as an elimination pathway. Conversion ratios between mercury concentrations in tissues and the whole chick body varied according to the contamination level.

16.
Environ Monit Assess ; 28(3): 255-62, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24221187

RESUMO

In 1991 we compared eggs, down and body feathers of chicks of Common Terns, Herring Gulls and Black-headed Gulls in their utility to assess contamination with mercury. Like eggs feathers distinctly show interspecific and intersite differences in contamination. Highest levels were found in Common Terns, lowest in Black-headed Gulls. Chicks hatched at the Elbe had much higher mercury levels than those in other areas of the German North Sea coast. Conversion ratios between tissues have to be used with caution.

19.
Health Phys ; 60(1): 77-80, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1983988

RESUMO

Selecting equipment to be used in emergencies is not a simple task. In the radiological accident that occurred in Goiânia, a large variety of instruments from different manufacturers were used, and we observed some of their limitations and advantages. This work presents, in a condensed form, the major problems that occurred with the equipment used in Goiânia and practical observations that could be helpful for instrument selection.


Assuntos
Acidentes , Radioisótopos de Césio , Exposição Ambiental , Monitoramento de Radiação/instrumentação , Radiometria/instrumentação , Brasil , Estudos de Avaliação como Assunto , Humanos , Teleterapia por Radioisótopo/instrumentação
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