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1.
Nat Commun ; 14(1): 4751, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550318

RESUMO

Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats, species, and functional groups. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities. Using a dataset encompassing six terrestrial faunal taxa (amphibians, bats, bees, birds, carabid beetles and reptiles) across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy showing the strongest response. Our findings suggest that urbanisation results in four trait syndromes (mobile generalists, site specialists, central place foragers, and mobile specialists), with resources associated with reproduction and diet likely driving patterns in traits associated with mobility and body size. Functional diversity measures showed varied responses, leading to shifts in trait space likely driven by critical resource distribution and abundance, and taxon-specific trait syndromes. Maximising opportunities to support taxa with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation and helps ensure that urban environments have the capacity to respond to future challenges. These actions are critical to reframe the role of cities in global biodiversity loss.


Assuntos
Quirópteros , Urbanização , Animais , Abelhas , Síndrome , Ecossistema , Biodiversidade , Aves
2.
BMJ Support Palliat Care ; 13(e1): e93-e95, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32792419

RESUMO

This paper describes a patient with an inoperable gastrointestinal stromal tumour with moderate volume malignant ascites. A large-volume paracentesis caused haemodynamic instability and a myocardial infarction. An indwelling right-sided peritoneal catheter was inserted following further ascites build-up. The patient experienced spontaneous acute rupture of tumour and subsequent loculated ascites. An additional second catheter was inserted to the left side of the abdomen following reaccumulation of ascites following liquefaction of cyst contents and successful one-off drainage on the left side of abdomen. This is the first case report of a patient with two indwelling catheters: we describe learning points pertaining to those as well as the rupture of gastrointestinal stromal tumours. Haemodynamic instability after paracentesis in malignant-related ascites has also not been described.


Assuntos
Tumores do Estroma Gastrointestinal , Infarto do Miocárdio , Humanos , Paracentese/efeitos adversos , Ascite/etiologia , Tumores do Estroma Gastrointestinal/complicações , Drenagem/efeitos adversos
3.
Healthcare (Basel) ; 9(10)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34682934

RESUMO

BACKGROUND: There is no national or local guidance for management of malignancy-related ascites (MRA). Modalities can include large volume paracentesis (LVP) and indwelling peritoneal catheter (IPeC) insertion. OBJECTIVES: We set up a local IPeC service and performed a retrospective review with local ethical (Caldicott) approval. We hypothesized that an IPeC service would reduce inpatient stay related to MRA management, would be acceptable to patients, and have minimal complications. METHODS: Notes of all patients requiring IPeC insertion were reviewed. Descriptive statistical methodology was applied with continuous data presented as mean (standard deviation (SD); range) and categorical variables as frequencies or percentages. Integrated Palliative Care Outcome Scale (IPOS) scores were collected for IPeC patients. RESULTS: Thirty-four patients were identified. They were predominantly female, with a mean age of 66.6 years and a wide range of cancer diagnoses. Twenty-nine were inserted as day case procedures, and 31 had preceding paracenteses (mean 2). Main complications were leakage (6(17%)), peritonitis (2(5.8%)), and skin infection (1(3%)). IPOS scores showed consistent improvement in symptoms. CONCLUSIONS: An IPeC service for malignant-related ascites is acceptable to patients and is associated with manageable complication rates. We present the development of our service and hope for widespread application.

4.
PLoS One ; 16(5): e0247900, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34038438

RESUMO

Cities around the world are transitioning to more efficient lighting schemes, especially retrofitting traditional, high-pressure sodium (HPS) streetlights with light-emitting diode (LED) lights. Although these initiatives aim to address the problems of urban sustainability and save money, the ecological impacts of these retrofits remain poorly understood, especially in brightly lit cities and in the tropics, where urbanisation is most rapid. We performed an experimental study of the retrofit in Singapore-focusing on insectivorous bats, whose activity we monitored acoustically along paired control (HPS-lit) and treatment (LED-lit) streets. We recorded seven species along these streets, but only obtained enough recordings to measure the effect of light type for three of them-all of which can reasonably be described as urban adapters. The strongest predictor of bat activity (an index of habitat use) was rainfall-it has a positive effect. Light type did not influence bat activity or species composition of the bat assemblage along these streets, though it did interact with the effects of rainfall and traffic noise for one bat species. Ultimately, the retrofit may be ecologically meaningless to urban-adapted, tropical insectivores that already experience high levels of light pollution as they do in Singapore. However, while our findings may appear reassuring to those concerned with such retrofits in other tropical and/or brightly-lit cities, they also highlight the contextual nature of ecological impacts. We point out that they should not be prematurely generalised to other locales and systems. In particular, they do not imply no impact on species that are less urban-adapted, and there is a clear need for further studies, for example, on responses of other foraging guilds and of bats (and insects) throughout the tropics.


Assuntos
Quirópteros/fisiologia , Luz , Comportamento Predatório/efeitos da radiação , Animais , Ecossistema , Singapura
6.
PLoS One ; 6(5): e20483, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21857890

RESUMO

BACKGROUND: We address three key gaps in research on urban wildlife ecology: insufficient attention to (1) grassland biomes, (2) individual- and population-level effects, and (3) vertebrates other than birds. We hypothesized that urbanization in the North American Prairies, by increasing habitat complexity (via the proliferation of vertical structures such as trees and buildings), thereby enhancing the availability of day-roosts, tree cover, and insects, would benefit synanthropic bats, resulting in increased fitness among urban individuals. METHODOLOGY/PRINCIPAL FINDINGS: Over three years, we captured more than 1,600 little brown bats (Myotis lucifugus) in urban and non-urban riparian sites in and around Calgary, Alberta, Canada. This species dominated bat assemblages throughout our study area, but nowhere more so than in the city. Our data did not support most of our specific predictions. Increased numbers of urban bats did not reflect urbanization-related benefits such as enhanced body condition, reproductive rates, or successful production of juveniles. Instead, bats did best in the transition zone situated between strictly urban and rural areas. CONCLUSIONS/SIGNIFICANCE: We reject our hypothesis and explore various explanations. One possibility is that urban and rural M. lucifugus exhibit increased use of anthropogenic roosts, as opposed to natural ones, leading to larger maternity colonies and higher population densities and, in turn, increased competition for insect prey. Other possibilities include increased stress, disease transmission and/or impacts of noise on urban bats. Whatever the proximate cause, the combination of greater bat population density with decreased body condition and production of juveniles indicates that Calgary does not represent a population source for Prairie bats. We studied a highly synanthropic species in a system where it could reasonably be expected to respond positively to urbanization, but failed to observe any apparent benefits at the individual level, leading us to propose that urban development may be universally detrimental to bats.


Assuntos
Quirópteros/crescimento & desenvolvimento , Demografia , Ecossistema , Urbanização , Alberta , Animais , Animais Recém-Nascidos , Peso Corporal/fisiologia , Osso e Ossos/anatomia & histologia , Feminino , Masculino , Tamanho do Órgão , Reprodução/fisiologia , Espermatogênese/fisiologia
7.
Environ Microbiol ; 8(4): 648-57, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16584476

RESUMO

The 16S ribosomal DNA based distinction between the bacterial and archaeal domains of life is strongly supported by the membrane lipid composition of the two domains; Bacteria generally contain dialkyl glycerol diester lipids, whereas Archaea produce isoprenoid dialkyl glycerol diether and membrane-spanning glycerol dialkyl glycerol tetraether (GDGT) lipids. Here we show that a new group of ecologically abundant membrane-spanning GDGT lipids, containing branched instead of isoprenoid carbon skeletons, are of a bacterial origin. This was revealed by examining the stereochemistry of the glycerol moieties of those branched tetraether membrane lipids, which was found to be the bacterial 1,2-di-O-alkyl-sn-glycerol stereoconfiguration and not the 2,3-di-O-alkyl-sn-glycerol stereoconfiguration as in archaeal membrane lipids. In addition, unequivocal evidence for the presence of cyclopentyl moieties in these bacterial membrane lipids was obtained by NMR. The biochemical traits of biosynthesis of tetraether membrane lipids and the formation of cyclopentyl moieties through internal cyclization, which were thought to be specific for the archaeal lineage of descent, thus also occur in the bacterial domain of life.


Assuntos
Archaea/química , Bactérias Anaeróbias , Éteres de Glicerila/análise , Lipídeos de Membrana/análise , Sphagnopsida/microbiologia , Archaea/crescimento & desenvolvimento , Bactérias Anaeróbias/química , Bactérias Anaeróbias/crescimento & desenvolvimento , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Estrutura Molecular , Filogenia , Estereoisomerismo
8.
Environ Microbiol ; 7(1): 66-77, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15643937

RESUMO

To explore further the diversity of the microorganisms and their relationship with geothermal sinters, we examined the lipids preserved in six sinters associated with four different hot spring (58-82 degrees C) areas of the Taupo Volcanic Zone (TVZ), New Zealand. These sinters contain microbial remains, but the process of mineralization has rendered them largely unidentifiable. Dominant lipids include free fatty acids, 1,2-diacylglycerophospholipids, 1,2-di-O-alkylglycerols, glycerol dialkylglycerol tetraethers and 1-O-alkylglycerols. These confirm the presence and, in some cases, high abundances of bacteria in all six sinters and archaea in four of the six sinter samples; in addition, the presence of novel macrocyclic diethers and unusual distributions of monoethers and diethers suggest the presence of previously uncharacterized bacteria. The lipid distributions are also markedly dissimilar among the four sites; for example, novel macrocyclic diethers are restricted to the Rotokawa samples while particularly abundant monoethers occur only in the Orakei Korako sample. Thus, biomarkers can provide crucial insight into the complex community structure of thermophilic microorganisms, including both archaea and bacteria, involved with biogenic silica sinter formation.


Assuntos
Archaea/classificação , Bactérias/classificação , Sedimentos Geológicos/microbiologia , Fontes Termais/microbiologia , Lipídeos/análise , Dióxido de Silício/análise , Archaea/química , Bactérias/química , Ecossistema , Ácidos Graxos/análise , Lipídeos/isolamento & purificação , Nova Zelândia , Fosfolipídeos/análise
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