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1.
Appl Spat Anal Policy ; 16(1): 461-484, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36405332

RESUMO

Measures of small area deprivation have played a major role in targeting resources in the UK. The English Index of Multiple Deprivation (IMD) is the official measure of small area deprivation in England and it has been used to allocate billions of pounds of government money. The success of schemes to reduce deprivation can only be assessed by measuring changes in deprivation over time. In addition, the effect of such schemes is likely to be a partly a function of the deprivation history of an area. More generally, the trajectory of deprivation, and not just its current state, is important in understanding the likely impacts of deprivation on those who live in deprived areas. This paper combines the strengths of the IMD as a broad-ranging measure based on administrative data (here, using the 2004, 2007, 2010, 2015 and 2019 indices) and the Townsend score derived from Census data for a much longer time period (1971 to 2011). In addition, benefit claimant count data are used as a proxy for unemployment following the national Covid-19 lockdowns. The paper identifies some major trends in small area deprivation and unemployment over the period 1971 to 2020 and it highlights some key similarities and differences between the Townsend score and the IMD and makes links to changes in unemployment in 2020. Areas with very long term deprivation are identified and the strong association between job losses following Covid-19 lockdown and deprivation histories is demonstrated. The analyses are used to argue that deprivation trajectories should be considered if effective strategies for reducing spatial inequalities are to be developed.

2.
J Fish Biol ; 92(5): 1651-1656, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29624685

RESUMO

Around 30% of Atlantic salmon Salmo salar smolts successfully survived passage through Loch Meig, a reservoir in the north of Scotland, en route to the sea. However, this survival rate was in turn dependent on the timing of migration, with the earliest migrants in the spring having the best chance of survival. This could have implication for fisheries management, since the estimation of smolt downstream survival may be influenced by which time period of the smolt run is analysed.


Assuntos
Migração Animal , Salmo salar/fisiologia , Estações do Ano , Animais , Oceanos e Mares , Rios , Escócia , Fatores de Tempo
3.
Mol Ecol ; 25(21): 5425-5438, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27662635

RESUMO

A larger body size confers many benefits, such as increased reproductive success, ability to evade predators and increased competitive ability and social status. However, individuals rarely maximize their growth rates, suggesting that this carries costs. One such cost could be faster attrition of the telomeres that cap the ends of eukaryotic chromosomes and play an important role in chromosome protection. A relatively short telomere length is indicative of poor biological state, including poorer tissue and organ performance, reduced potential longevity and increased disease susceptibility. Telomere loss during growth may also be accelerated by environmental factors, but these have rarely been subjected to experimental manipulation in the natural environment. Using a wild system involving experimental manipulations of juvenile Atlantic salmon Salmo salar in Scottish streams, we found that telomere length in juvenile fish was influenced by parental traits and by direct environmental effects. We found that faster-growing fish had shorter telomeres and there was a greater cost (in terms of reduced telomere length) if the growth occurred in a harsher environment. We also found a positive association between offspring telomere length and the growth history of their fathers (but not mothers), represented by the number of years fathers had spent at sea. This suggests that there may be long-term consequences of growth conditions and parental life history for individual longevity.


Assuntos
Salmo salar/crescimento & desenvolvimento , Salmo salar/genética , Encurtamento do Telômero , Telômero/ultraestrutura , Animais , Tamanho Corporal , Meio Ambiente , Feminino , Longevidade , Masculino , Escócia
4.
Pharm Res ; 18(11): 1620-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11758772

RESUMO

PURPOSE: This study was conducted to explore the role of the peripheral lymphatics in insulin absorption following subcutaneous (SC) administration using a sheep model that allows continuous collection of peripheral lymph and simultaneous assessment of systemic bioavailability. METHODS: In a parallel group design, soluble human insulin (0.5 IU/kg) was administered by bolus SC injection into the interdigital space of the hind leg of non-cannulated control sheep, and sheep in which the efferent popliteal lymph duct was cannulated. A separate group received a bolus IV injection (0.15 IU/kg). Blood was sampled from all animals, and lymph was collected continuously over 12 h postdosing. Samples were assayed for insulin by ELISA. RESULTS: The SC bioavailability of insulin in control sheep was 31.5+/-3.2%, which was significantly higher than when the peripheral lymph was continuously collected (18.4+/-1.7%). In the lymph-cannulated animals, 17.3+/-1.0% of the dose was collected in peripheral lymph. CONCLUSIONS: Based on the direct measurement of insulin in regional lymph and on the decrease in the systemic bioavailability when regional lymph was continuously collected, the results demonstrate that lymphatic absorption contributed significantly to the overall insulin bioavailability following SC administration to sheep.


Assuntos
Hipoglicemiantes/farmacocinética , Insulina/farmacocinética , Sistema Linfático/metabolismo , Absorção , Animais , Área Sob a Curva , Disponibilidade Biológica , Ensaio de Imunoadsorção Enzimática , Hipoglicemiantes/administração & dosagem , Injeções Intravenosas , Injeções Subcutâneas , Insulina/administração & dosagem , Linfa/metabolismo , Reprodutibilidade dos Testes , Ovinos
5.
J Parasitol ; 85(3): 540-4, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10386450

RESUMO

The Eucestoda is particularly relevant for questions concerning reproductive investment in male gametes because no other parasitic group displays such diversity in testis size and number within and among species. This diversity has long been used as a valuable taxonomic character, but few researchers have ever investigated its evolutionary significance. In this paper we investigate the evolution of testis number and size within Rhinebothroides (Platyhelminthes: Eucestoda). Our comparative, phylogenetic analysis revealed that overall allocation to male functions, as measured by relative testicular area, does not change within the clade, even though the packaging of that investment in numerous testes is highly variable within, and diverse among, members of the group.


Assuntos
Evolução Biológica , Cestoides/fisiologia , Transtornos do Desenvolvimento Sexual , Análise de Variância , Animais , Masculino
6.
7.
J Nematol ; 31(2): 117-33, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19270882

RESUMO

The most appropriate ontological basis for understanding the role of species in evolutionary biology is the Evolutionary Species Concept. The ESC is not an operational concept, but one version of the Phylogenetic Species Concept is. Linking the ontology of species with the epistemological basis of actual biological studies requires that we specify both a discovery mode for identifying collections of organisms that we believe are evolutionary species, and a series of evaluation criteria for assessing those entities we have discovered. Simply naming a collection of specimens, no matter how strong one's evolutionary beliefs, is not sufficient for declaring that evolutionary species have been discovered. All operational historical species concepts represent discovery modes with minimal evaluation criteria; all operational non-dimensional species concepts represent evaluation criteria that do not specify discovery modes. Thus, both categories of knowledge are necessary and neither is sufficient for assigning species status. This leads naturally to a hierarchical research program in historical ecology, beginning with phylogenetic analysis of a group of entities postulated to be evolutionary species, which provides a productive arena for our arguments about species concepts.

8.
Am J Hum Genet ; 62(3): 653-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9497242

RESUMO

Prostate cancer shows evidence of familial aggregation, particularly at young ages at diagnosis, but the inherited basis of familial prostate cancer is poorly understood. Smith et al. recently found evidence of linkage to markers on 1q, at a locus designated "HPC1," in 91 families with multiple cases of early-onset prostate cancer. Using both parametric and nonparametric methods, we attempted to confirm this finding, in 60 affected related pairs and in 76 families with three or more cases of prostate cancer, but we found no significant evidence of linkage. The estimated proportion of linked families, under a standard autosomal dominant model, was 4%, with an upper 95% confidence limit of 31%. We conclude that the HPC1 locus is responsible for only a minority of familial prostate cancer cases and that it is likely to be most important in families with at least four cases of the disease.


Assuntos
Cromossomos Humanos Par 1 , Ligação Genética , Marcadores Genéticos , Neoplasias da Próstata/genética , Heterogeneidade Genética , Predisposição Genética para Doença , Humanos , Escore Lod , Masculino
9.
J Parasitol ; 81(5): 675-82, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7472854

RESUMO

We investigated the influence of 2 intestinal helminths, Bunodera inconstans and Neoechinorhynchus rutili, on the development of female behavioral and morphological characters in brook sticklebacks. The number of N. rutili per female is positively correlated with standard length. Both the number of B. inconstans per female and the number of N. rutili per female are negatively correlated with the intensity of a female's aggressive response to an intruding female and are positively correlated with the intensity and duration of female courtship. The results of this study indicate that infection with N. rutili and B. inconstans may influence a female brook stickleback's ability either to compete for a mate or to sample from a large subset of territorial males.


Assuntos
Acantocéfalos/fisiologia , Comportamento Animal , Peixes/parasitologia , Helmintíase Animal , Trematódeos/fisiologia , Infecções por Trematódeos/veterinária , Animais , Feminino , Doenças dos Peixes/parasitologia , Helmintíase/parasitologia , Interações Hospedeiro-Parasita , Masculino , Comportamento Sexual Animal , Infecções por Trematódeos/parasitologia
10.
Am Nat ; 142(5): 755-78, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19425955

RESUMO

Studies of adaptive radiations require robust phylogenies, estimates of species numbers for monophyletic groups within clades, assessments of the adaptive value of putative key innovations, and estimates of the frequency of speciation modes. Four criteria are necessary to identify an adaptive radiation within the parasitic platyhelminths: (1) a group contains significantly more species than its sister group, (2) species richness is apomorphic, (3) apomorphic traits enhance the potential for adaptively driven modes of speciation (sympatric speciation and speciation by peripheral isolation via host switching), and (4) the frequency of adaptively driven speciation modes is high within the group when compared with data from free-living groups. Only the species-rich Monogenea fulfill all four criteria. The Digenea and Eucestoda also are more species rich than their sister groups, their species richness is derived, and they possess unique characters that increase the potential for host switching to occur However, because there is not enough information to determine whether the frequency of adaptive modes of speciation is high for those groups, we cannot yet assert that their radiations have been adaptive.

11.
13.
Trends Ecol Evol ; 7(2): 55-9, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21235951

RESUMO

Historical ecological studies provide information about the origins of species in an area and the origins of traits characterizing the interactions between those species and their environment. Incorporating this evolutionary information into conservation policies will broaden the base of options for making effective decisions about the preservation of biodiversity.

14.
Trends Ecol Evol ; 7(10): 353, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21236064
15.
Q Rev Biol ; 66(3): 255-86, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1745728

RESUMO

The Hamilton-Zuk hypothesis postulates a causal link between parasitism and the evolution of epigamic traits by intersexual selection. Oversimplified assumptions about basic parasite biology, ambiguous formulation of the hypothesis, and poor communication between ethologists and parasitologists have hampered its testing. The hypothesis is supported at the microevolutionary level if females show significant preference for lightly or uninfected males, if intensity of infection reflects host resistance to parasites that depress host fitness by causing disease, and if intensity of infection is related to the degree of epigamic development. It must be shown that particular parasites cause disease, that the host population is polymorphic for resistance to infection by those species, and that female hosts are capable of distinguishing male hosts with low parasite loads due to heritable aspects of host resistance from males that are uninfected due to chance. The macroevolutionary prediction of the hypothesis, that species displaying strongly developed epigamic characters should host "more parasites" than species with weakly developed epigamic traits, contradicts the microevolutionary dynamic of the hypothesis, and is too ambiguous. We propose a macroevolutionary prediction based on understanding the evolutionary origin of epigamic traits and the evolutionary origin of each host-parasite association. Associations originating in the ancestor in which the epigamic trait appeared corroborate the hypothesis most strongly; those originating prior to the evolution of the epigamic trait corroborate it weakly; those beginning after the origin of the epigamic trait could not have been involved in the origin and spread of the epigamic trait.


Assuntos
Parasitos/genética , Seleção Genética , Comportamento Sexual Animal , Animais , Evolução Biológica , Feminino , Interações Hospedeiro-Parasita , Masculino , Modelos Genéticos , Filogenia , Caracteres Sexuais
16.
Gynecol Oncol ; 34(1): 61-5, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2737528

RESUMO

The timing of treatment for stage I-B cervical carcinoma diagnosed during pregnancy is complicated by conflicting concerns for fetal survival and control of malignancy. There were 11 pregnant women with stage I-B cervical carcinoma diagnosed prior to fetal viability since 1969. Six patients were managed with termination of pregnancy and radical hysterectomy with pelvic lymphadenectomy. In 5 patients, treatment was delayed for 6 to 17 weeks and then delivery was accomplished by cesarean section followed directly by radical hysterectomy and pelvic lymphadenectomy. Two of the infants experienced complicated neonatal courses and would have benefited from additional delay. Benefits that could be achieved by delaying delivery for the fetus were calculated from a review of 600 inborn infants without congenital anomalies admitted to the neonatal intensive care (NICU) during 1984 and 1985. Neonatal mortality decreased from 32.8% at 26-27 weeks to 2.7% at 34-35 weeks gestation. Similar improvements in neonatal morbidity were demonstrated. Although adverse maternal outcomes were not associated with delay, an evaluation of risk cannot be derived from this series. Significant fetal benefit can accrue from relatively short delays in planned delivery dates. When stage I-B cervical carcinoma is diagnosed during pregnancy and when fetal survival is desired, delivery should be delayed to achieve fetal maturity, rather than only potential viability.


Assuntos
Complicações Neoplásicas na Gravidez/terapia , Neoplasias do Colo do Útero/terapia , Adulto , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Masculino , Estadiamento de Neoplasias , Gravidez , Fatores de Tempo
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