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1.
J Robot Surg ; 18(1): 24, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217830

RESUMO

In the era of robotic prostate surgery, various techniques have been developed to improve functional outcomes. Urinary continence has shown satisfactory results, but the preservation of lateral nerves to the periprostatic capsule is only achievable by sparing the pubovesical complex. This study aims to present the first cases of lateral-approach robot-assisted radical prostatectomy (LRRP) performed by a novice surgeon. We conducted a retrospective analysis of 70 prostate cancer patients who underwent LRRP between October 2019 and September 2021, analyzing the perioperative and functional outcomes. The median operative time and intraoperative blood loss were 102 (92-108) minutes and 150 (130-180) mL, respectively. Five minor postoperative complications were reported, and the median hospital stay was 2 (1-2) days. Eleven positive surgical margins occurred. Potency and urinary continence recovery were achieved in 59 (84%) and 66 (94%) patients, respectively, 12 months after surgery. Our analysis shows that LRRP is a safe and effective procedure for prostate cancer surgery. Continence and potency recovery required a short learning curve, with an acceptable recovery rate even in the initial cases.


Assuntos
Neoplasias da Próstata , Procedimentos Cirúrgicos Robóticos , Robótica , Cirurgiões , Incontinência Urinária , Masculino , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Próstata/cirurgia , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle , Estudos Retrospectivos , Prostatectomia/métodos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/complicações , Resultado do Tratamento
2.
Surg Endosc ; 37(7): 5708-5713, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37208481

RESUMO

OBJECTIVE: Pudendal Nerve Entrapment (PNE) may determine chronic pelvic pain associated with symptoms related to its innervation area. This study aimed to present the technique and report the outcomes of the first series of robot-assisted pudendal nerve release (RPNR). PATIENTS AND METHODS: 32 patients, who were treated with RPNR in our centre between January 2016 and July 2021, were recruited. Following the medial umbilical ligament identification, the space between this ligament and the ipsilateral external iliac pedicle is progressively dissected to identify the obturator nerve. The dissection medial to this nerve identifies the obturator vein and the arcus tendinous of the levator ani, which is cranially inserted into the ischial spine. Following the cold incision of the coccygeous muscle at the level of the spine, the sacrospinous ligament is identified and incised. The pudendal trunk (vessels and nerve) is visualized, freed from the ischial spine and medially transposed. RESULTS: The Median duration of symptoms was 7 (5, 5-9) years. The median operative time was 74 (65-83) minutes. The median length of stay was 1 (1-2) days. There was only a minor complication. At 3 and 6 months after surgery, a statistically significant pain reduction has been encountered. Furthermore, the Pearson correlation coefficient reported a negative relationship between the duration of pain and the improvement in NPRS score, - 0.81 (p = 0.01). CONCLUSIONS: RPNR is a safe and effective approach for the pain resolution caused by PNE. Timely nerve decompression is suggested to enhance outcomes.


Assuntos
Nervo Pudendo , Neuralgia do Pudendo , Robótica , Humanos , Nervo Pudendo/cirurgia , Neuralgia do Pudendo/etiologia , Neuralgia do Pudendo/cirurgia , Dor Pélvica/etiologia , Dor Pélvica/cirurgia , Diafragma da Pelve/inervação
3.
Adv Mater ; 32(14): e1907565, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32091144

RESUMO

Parity-time symmetry plays an essential role for the formation of Dirac states in Dirac semimetals. So far, all of the experimentally identified topologically nontrivial Dirac semimetals (DSMs) possess both parity and time reversal symmetry. The realization of magnetic topological DSMs remains a major issue in topological material research. Here, combining angle-resolved photoemission spectroscopy with density functional theory calculations, it is ascertained that band inversion induces a topologically nontrivial ground state in EuCd2 As2 . As a result, ideal magnetic Dirac fermions with simplest double cone structure near the Fermi level emerge in the antiferromagnetic (AFM) phase. The magnetic order breaks time reversal symmetry, but preserves inversion symmetry. The double degeneracy of the Dirac bands is protected by a combination of inversion, time-reversal, and an additional translation operation. Moreover, the calculations show that a deviation of the magnetic moments from the c-axis leads to the breaking of C3 rotation symmetry, and thus, a small bandgap opens at the Dirac point in the bulk. In this case, the system hosts a novel state containing three different types of topological insulator: axion insulator, AFM topological crystalline insulator (TCI), and higher order topological insulator. The results provide an enlarged platform for the quest of topological Dirac fermions in a magnetic system.

4.
Nat Commun ; 9(1): 3640, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30194308

RESUMO

Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of peat in (sub)tropical regions remains enigmatic. Here we examined peat and plant chemistry across a latitudinal transect from the Arctic to the tropics. Near-surface low-latitude peat has lower carbohydrate and greater aromatic content than near-surface high-latitude peat, creating a reduced oxidation state and resulting recalcitrance. This recalcitrance allows peat to persist in the (sub)tropics despite warm temperatures. Because we observed similar declines in carbohydrate content with depth in high-latitude peat, our data explain recent field-scale deep peat warming experiments in which catotelm (deeper) peat remained stable despite temperature increases up to 9 °C. We suggest that high-latitude deep peat reservoirs may be stabilized in the face of climate change by their ultimately lower carbohydrate and higher aromatic composition, similar to tropical peats.

5.
PLoS One ; 12(8): e0181045, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767655

RESUMO

To understand beluga whale (Delphinapterus leucas) estuarine use in the Nelson River estuary, southwest Hudson Bay, we recorded and examined beluga movements and habitat associations for the July through August period in 2002-2005. We compared locations of belugas fitted with satellite transmitters ("tags") (2002-2005) and aerial-surveyed (2003 and 2005) belugas for years of differing freshwater flow from the Nelson River which is influenced by hydroelectric activity. Using the beluga telemetry location data, we estimated an early August behavioral shift in beluga distribution patterns from local estuarine use to a progressively more migratory behavior away from the estuary. The timing of this shift in behavior was also apparent in results of beluga aerial surveys from the 1940s-1960s, despite environmental changes including later freeze-up and warming ocean temperatures. Overall, during the higher than average discharge ("wet") year of 2005, the three tagged belugas ranged farther from the Nelson River but not farther from the nearest shore along southwestern Hudson Bay, compared to the 10 tagged belugas tracked during the "dry" years of 2002-2004 with below average discharges. Aerial survey data for 2003 and 2005 display a similar dry vs. wet year shift in spatial patterns, with no significant change in overall density of belugas within the study area. In the Nelson estuary, proximity to the fresh-salt water mixing area may be more important than the shallow waters of the upper estuary. Killer whales (Orcinus orca) were observed in the Churchill area (200 km northwest) during each year of study, 2002-05, and belugas may benefit from the proximity to shallow estuary waters that provide protection from the larger-bodied predator. Study results contribute to an understanding of the influence of environmental variation on how and why belugas use estuaries although considerable uncertainties exist and additional research is required.


Assuntos
Beluga/fisiologia , Ecossistema , Migração Animal/fisiologia , Animais , Canadá , Estuários , Sistemas de Informação Geográfica , Rios , Estações do Ano
6.
Sci Adv ; 3(5): e1602415, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28508059

RESUMO

Topological insulators (TIs) host novel states of quantum matter characterized by nontrivial conducting boundary states connecting valence and conduction bulk bands. All TIs discovered experimentally so far rely on either time-reversal or mirror crystal symmorphic symmetry to protect massless Dirac-like boundary states. Several materials were recently proposed to be TIs with nonsymmorphic symmetry, where a glide mirror protects exotic surface fermions with hourglass-shaped dispersion. However, an experimental confirmation of this new fermion is missing. Using angle-resolved photoemission spectroscopy, we provide experimental evidence of hourglass fermions on the (010) surface of crystalline KHgSb, whereas the (001) surface has no boundary state, in agreement with first-principles calculations. Our study will stimulate further research activities of topological properties of nonsymmorphic materials.

7.
PLoS One ; 12(2): e0172755, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28235041

RESUMO

There has been extensive sea ice loss in the Chukchi and Beaufort seas where two beluga whale (Delphinapterus leucas) populations occur between July-November. Our goal was to develop population-specific beluga habitat selection models that quantify relative use of sea ice and bathymetric features related to oceanographic processes, which can provide context to the importance of changing sea ice conditions. We established habitat selection models that incorporated daily sea ice measures (sea ice concentration, proximity to ice edge and dense ice) and bathymetric features (slope, depth, proximity to the continental slope, Barrow Canyon, and shore) to establish quantitative estimates of habitat use for the Eastern Chukchi Sea ('Chukchi') and Eastern Beaufort Sea ('Beaufort') populations. We applied 'used v. available' resource selection functions to locations of 65 whales tagged from 1993-2012, revealing large variations in seasonal habitat selection that were distinct between sex and population groups. Chukchi whales of both sexes were predicted to use areas in close proximity to Barrow Canyon (typically <200 km) as well as the continental slope in summer, although deeper water and denser ice were stronger predictors for males than females. Habitat selection differed more between sexes for Beaufort belugas. Beaufort males selected higher ice concentrations (≥40%) than females (0-40%) in July-August. Proximity to shore (<200 km) strongly predicted summer habitat of Beaufort females, while distance to the ice edge was important for male habitat selection, especially during westward migration in September. Overall, our results indicate that sea ice variables were rarely the primary drivers of beluga summer-fall habitat selection. While diminished sea ice may indirectly affect belugas through changes in the ecosystem, associations with bathymetric features that affect prey availability seemed key to habitat selection during summer and fall. These results provide a benchmark by which to assess future changes in beluga habitat use of the Pacific Arctic.


Assuntos
Beluga/fisiologia , Ecossistema , Monitoramento Ambiental , Controle da População , Animais , Regiões Árticas , Masculino , Oceanos e Mares , Estações do Ano
8.
Glob Chang Biol ; 23(6): 2206-2217, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28001336

RESUMO

Migrations are often influenced by seasonal environmental gradients that are increasingly being altered by climate change. The consequences of rapid changes in Arctic sea ice have the potential to affect migrations of a number of marine species whose timing is temporally matched to seasonal sea ice cover. This topic has not been investigated for Pacific Arctic beluga whales (Delphinapterus leucas) that follow matrilineally maintained autumn migrations in the waters around Alaska and Russia. For the sympatric Eastern Chukchi Sea ('Chukchi') and Eastern Beaufort Sea ('Beaufort') beluga populations, we examined changes in autumn migration timing as related to delayed regional sea ice freeze-up since the 1990s, using two independent data sources (satellite telemetry data and passive acoustics) for both populations. We compared dates of migration between 'early' (1993-2002) and 'late' (2004-2012) tagging periods. During the late tagging period, Chukchi belugas had significantly delayed migrations (by 2 to >4 weeks, depending on location) from the Beaufort and Chukchi seas. Spatial analyses also revealed that departure from Beaufort Sea foraging regions by Chukchi whales was postponed in the late period. Chukchi beluga autumn migration timing occurred significantly later as regional sea ice freeze-up timing became later in the Beaufort, Chukchi, and Bering seas. In contrast, Beaufort belugas did not shift migration timing between periods, nor was migration timing related to freeze-up timing, other than for southward migration at the Bering Strait. Passive acoustic data from 2008 to 2014 provided independent and supplementary support for delayed migration from the Beaufort Sea (4 day yr-1 ) by Chukchi belugas. Here, we report the first phenological study examining beluga whale migrations within the context of their rapidly transforming Pacific Arctic ecosystem, suggesting flexible responses that may enable their persistence yet also complicate predictions of how belugas may fare in the future.


Assuntos
Migração Animal , Beluga , Mudança Climática , Camada de Gelo , Alaska , Animais , Regiões Árticas , Oceanos e Mares , Federação Russa , Baleias
9.
Sci Bull (Beijing) ; 62(7): 503-507, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36659260

RESUMO

We performed angle-resolved photoemission spectroscopy studies on a series of FeTe1-xSex monolayer films grown on SrTiO3. The superconductivity of the films is robust and rather insensitive to the variations of the band position and effective mass caused by the substitution of Se by Te. However, the band gap between the electron- and hole-like bands at the Brillouin zone center decreases towards band inversion and parity exchange, which drive the system to a nontrivial topological state predicted by theoretical calculations. Our results provide a clear experimental indication that the FeTe1-xSex monolayer materials are high-temperature connate topological superconductors in which band topology and superconductivity are integrated intrinsically.

10.
Ann Nutr Metab ; 68 Suppl 2: 35-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27300305

RESUMO

BACKGROUND: Tackling inequalities in overweight, obesity and related complications has become a top priority for European research and policy agendas. It is well-known that the health message often does not reach disadvantaged populations, a phenomenon that widens health inequalities. Ensemble Prévenons l'Obésité des Enfants (EPODE) methodology is an innovative approach to counteract obesity and improve health equity. EPODE for the Promotion of Health Equity (EPHE) has assessed the impact and sustainability of the EPODE methodology to diminish inequalities in childhood obesity prevention. The current data represent the results of the intermediate measurements that were obtained following EPHE interventions in 7 European communities across different countries. METHODS: A total of 1,062 children aged 6-8 years and their parents from different socioeconomic backgrounds were observed for 2 years. A self-administrated questionnaire was sent to parents to measure the children's energy balance-related behaviors and their determinants. The Wilcoxon signed-rank test was used to test differences between baseline and intermediate measurements for each socioeconomic group. RESULTS: We observed changes in behaviors (fruit and vegetable consumption, sugary sweetened beverage consumption, screen exposure) and their related determinants, within the low and high education groups, which were associated with identified inequity gaps at baseline. Although statistical significance was not reached in most of the cases, greater improvements in behaviors were evident within the low education groups. CONCLUSIONS: Our findings show that, after EPODE interventions, the low socioeconomic groups improved their behavior compared to the other socio-economic groups. This indicates that the EPODE methodology has the capacity not only to reduce obesity prevalence but also to decrease health inequities.


Assuntos
Serviços de Saúde Comunitária , Comportamentos Relacionados com a Saúde , Educação em Saúde/métodos , Equidade em Saúde/estatística & dados numéricos , Obesidade Infantil/epidemiologia , Fatores Socioeconômicos , Criança , Dieta , Ingestão de Líquidos , Escolaridade , Metabolismo Energético , França , Frutas , Promoção da Saúde/métodos , Acessibilidade aos Serviços de Saúde , Humanos , Sobrepeso/epidemiologia , Pais , Obesidade Infantil/prevenção & controle , Inquéritos e Questionários , Verduras
11.
PLoS One ; 11(5): e0154950, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27149113

RESUMO

We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.


Assuntos
Plantas/metabolismo , Animais , Regiões Árticas , Aves , Ecossistema , Alimentos , Nitrogênio/metabolismo , Salix/metabolismo , Salix/fisiologia , Solo , Svalbard , Tundra
12.
Sci Total Environ ; 542(Pt A): 306-14, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26519590

RESUMO

To determine the dominant nitrogen sources and select effective macroalgal species for monitoring eutrophication along the Yantai coast, the total carbon (TOC), total nitrogen (TN) and nitrogen stable isotope ratio (δ(15)N) in macroalgal tissue were analyzed in conjunction with environmental variables in seawater along the Yantai coastline. The ranges of macroalgal tissue δ(15)N values together with dissolved inorganic nitrogen (DIN) composition indicated that except for the atmospheric deposition, there were three dominant types of nitrogen sources along the Yantai coast, with the agricultural fertilizer usage and factorial wastewater input at the S1 (Zhifu Island coast), the sewage discharge at S2 (the Moon Bay coast), the sewage discharge together with aquaculture impacts at S3 (Fisherman Wharf coast) and S4 (the Horse Island coast). Macroalgal growth were not limited by DIN but limited by P at S2, S3 and S4. Macroalgal species suitable or not for DIN source tracing along the Yantai coast were discussed. For sites with low DIN concentration, many species of three phyla could be used for DIN sources tracing with Laurencia okamurai, Gloiopeltis furcata and Ulva pertusa being ideal species. For site with high DIN concentration, however, species of Rhodophyta were not suitable and only Scytosiphon lomentaria and Monostroma nitidium were chosen.


Assuntos
Monitoramento Ambiental , Nitrogênio/análise , Poluentes Químicos da Água/análise , Aquicultura , China , Clorófitas , Eutrofização , Isótopos de Nitrogênio/análise , Phaeophyceae , Água do Mar/química , Esgotos
13.
Anal Chem ; 87(23): 11732-8, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26511394

RESUMO

A critical component of the biogeochemical cycle of mercury (Hg) is the transformation of inorganic Hg to neurotoxic monomethylmercury (CH3Hg). Humans are exposed to CH3Hg by consuming marine fish, yet the origin of CH3Hg in fish is a topic of debate. The carbon stable isotopic composition (δ(13)C) embedded in the methyl group of CH3Hg remains unexplored. This new isotopic information at the molecular level is thought to represent a new proxy to trace the carbon source at the origin of CH3Hg. Here, we present a compound-specific stable isotope analysis (CSIA) technique for the determination of the δ(13)C value of CH3Hg in biological samples by gas chromatography combustion isotope ratio mass spectrometry analysis (GC-C-IRMS). The method consists first of calibrating a CH3Hg standard solution for δ(13)C CSIA. This was achieved by comparing three independent approaches consisting of the derivatization and halogenation of the CH3Hg standard solution. The determination of δ(13)C(CH3Hg) values on natural biological samples was performed by combining a CH3Hg selective extraction, purification, and halogenation followed by GC-C-IRMS analysis. Reference δ(13)C values were established for a tuna fish certified material (ERM-CE464) originating from the Adriatic Sea (δ(13)C(CH3Hg) = -22.1 ± 1.5‰, ± 2 SD). This value is similar to the δ(13)C value of marine algal-derived particulate organic carbon (δ(13)CPOC = -21‰).


Assuntos
Compostos de Metilmercúrio/análise , Atum , Animais , Isótopos de Carbono/análise , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas
14.
Environ Sci Technol ; 49(15): 8977-85, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26132925

RESUMO

Decadal time trends of mercury (Hg) concentrations in Arctic biota suggest that anthropogenic Hg is not the single dominant factor modulating Hg exposure to Arctic wildlife. Here, we present Hg speciation (monomethyl-Hg) and stable isotopic composition (C, N, Hg) of 53 Alaskan ringed seal liver samples covering a period of 14 years (1988-2002). In vivo metabolic effects and foraging ecology explain most of the observed 1.6 ‰ variation in liver δ(202)Hg, but not Δ(199)Hg. Ringed seal habitat use and migration were the most likely factors explaining Δ(199)Hg variations. Average Δ(199)Hg in ringed seal liver samples from Barrow increased significantly from +0.38 ± 0.08‰ (±SE, n = 5) in 1988 to +0.59 ± 0.07‰ (±SE, n = 7) in 2002 (4.1 ± 1.2% per year, p < 0.001). Δ(199)Hg in marine biological tissues is thought to reflect marine Hg photochemistry before biouptake and bioaccumulation. A spatiotemporal analysis of sea ice cover that accounts for the habitat of ringed seals suggests that the observed increase in Δ(199)Hg may have been caused by the progressive summer sea ice disappearance between 1988 and 2002. While changes in seal liver Δ(199)Hg values suggests a mild sea ice control on marine MMHg breakdown, the effect is not large enough to induce measurable HgT changes in biota. This suggests that Hg trends in biota in the context of a warming Arctic are likely controlled by other processes.


Assuntos
Monitoramento Ambiental , Camada de Gelo , Marcação por Isótopo , Focas Verdadeiras/metabolismo , Alaska , Animais , Regiões Árticas , Ecossistema , Geografia , Fígado/metabolismo , Isótopos de Mercúrio/análise , Fatores de Tempo
15.
Ecology ; 95(8): 2324-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25230482

RESUMO

Evidence of age-dependent changes in foraging behavior of free-ranging individuals is scarce, especially at older stages. Using the isotopic niche as a proxy of the trophic niche during both the breeding (blood) and inter-nesting (feather) periods, we report here empirical evidence for age-, gender-, and breeding status-dependent foraging ecology and examine its potential consequences on subsequent reproduction and survival in an extremely long-lived species, the Wandering Albatross (Diomedea exulans). Immature Wandering Albatrosses of both sexes forage in the subtropics (delta13C) and feed at the same trophic position (delta15N) as the adults. In contrast to immature birds, adult females forage, on average, at more northern latitudes than males, with both sexes feeding in the subtropics during the internesting period, and males, not females, favoring subantarctic waters during incubation. In contrast to adult females, males show a unique pattern among birds and mammals of a continuous change with age in their main feeding habitat by foraging progressively farther south in colder waters during both the breeding and inter-nesting periods. In males, foraging at higher latitudes (lower feather delta13C values) is associated with a lower probability of breeding during the following years compared to other birds, but with no effect on their probability of surviving. Foraging in cold and windy waters may be linked to foraging impairment that might explain different life history trade-offs and lower investment in reproduction with age. This key point requires further longitudinal investigations and/or studies examining foraging success and the energy budget of birds feeding in different water masses.


Assuntos
Envelhecimento/fisiologia , Anseriformes/fisiologia , Comportamento Alimentar/fisiologia , Reprodução/fisiologia , Animais , Anseriformes/sangue , Carbono/metabolismo , Isótopos de Carbono , Plumas/química , Feminino , Masculino , Nitrogênio/metabolismo , Isótopos de Nitrogênio , Fatores Sexuais
17.
PLoS One ; 8(10): e76739, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24204666

RESUMO

The migratory shorebirds of the East Atlantic flyway land in huge numbers during a migratory stopover or wintering on the French Atlantic coast. The Brouage bare mudflat (Marennes-Oléron Bay, NE Atlantic) is one of the major stopover sites in France. The particular structure and function of a food web affects the efficiency of carbon transfer. The structure and functioning of the Brouage food web is crucial for the conservation of species landing within this area because it provides sufficient food, which allows shorebirds to reach the north of Europe where they nest. The aim of this study was to describe and understand which food web characteristics support nutritional needs of birds. Two food-web models were constructed, based on in situ measurements that were made in February 2008 (the presence of birds) and July 2008 (absence of birds). To complete the models, allometric relationships and additional data from the literature were used. The missing flow values of the food web models were estimated by Monte Carlo Markov Chain--Linear Inverse Modelling. The flow solutions obtained were used to calculate the ecological network analysis indices, which estimate the emergent properties of the functioning of a food-web. The total activities of the Brouage ecosystem in February and July are significantly different. The specialisation of the trophic links within the ecosystem does not appear to differ between the two models. In spite of a large export of carbon from the primary producer and detritus in winter, the higher recycling leads to a similar retention of carbon for the two seasons. It can be concluded that in February, the higher activity of the ecosystem coupled with a higher cycling and a mean internal organization, ensure the sufficient feeding of the migratory shorebirds.


Assuntos
Migração Animal/fisiologia , Aves/fisiologia , Ecossistema , Cadeia Alimentar , Animais , Oceano Atlântico , Bactérias/crescimento & desenvolvimento , Baías , França , Geografia , Invertebrados/crescimento & desenvolvimento , Cadeias de Markov , Modelos Biológicos , Método de Monte Carlo , Estações do Ano
18.
Mar Pollut Bull ; 77(1-2): 227-36, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24161435

RESUMO

Total organic carbon (TOC), total nitrogen (TN), δ(13)C and δ(15)N were measured in sediment cores at three sites in Sishili Bay, China, to track the impacts of anthropogenic activities on the coastal environment over the last 100 years. The increased TOC and TN in the upper section of sediment cores indicated a eutrophic process since 1975. In comparison, the TOC and TN in the sediment core near to a scallop aquaculture area displayed a much slower increase, indicating the contribution of scallop aquaculture in mitigating eutrophication. Combined information from δ(13)C, δ(15)N and TOC:TN indicated an increased terrestrial signal, although organic matter sources in Sishili Bay featured a mixture of terrestrial and marine sources, with phytoplankton being dominant. Increased fertilizer use since 1970s contributed to the eutrophic process in Sishili Bay since 1975, and increased sewage discharge from 1990s has added to this process.


Assuntos
Baías/química , Monitoramento Ambiental , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Aquicultura , China , Eutrofização , Nitrogênio/análise , Poluição Química da Água/estatística & dados numéricos
19.
J Diabetes Sci Technol ; 7(3): 699-707, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23759403

RESUMO

BACKGROUND: Most closed-loop insulin delivery systems rely on model-based controllers to control the blood glucose (BG) level. Simple models of glucose metabolism, which allow easy design of the control law, are limited in their parametric identification from raw data. New control models and controllers issued from them are needed. METHODS: A proportional integral derivative with double phase lead controller was proposed. Its design was based on a linearization of a new nonlinear control model of the glucose-insulin system in type 1 diabetes mellitus (T1DM) patients validated with the University of Virginia/Padova T1DM metabolic simulator. A 36 h scenario, including six unannounced meals, was tested in nine virtual adults. A previous trial database has been used to compare the performance of our controller with their previous results. The scenario was repeated 25 times for each adult in order to take continuous glucose monitoring noise into account. The primary outcome was the time BG levels were in target (70-180 mg/dl). RESULTS: Blood glucose values were in the target range for 77% of the time and below 50 mg/dl and above 250 mg/dl for 0.8% and 0.3% of the time, respectively. The low blood glucose index and high blood glucose index were 1.65 and 3.33, respectively. CONCLUSION: The linear controller presented, based on the linearization of a new easily identifiable nonlinear model, achieves good glucose control with low exposure to hypoglycemia and hyperglycemia.


Assuntos
Algoritmos , Glicemia/análise , Diabetes Mellitus Tipo 1/sangue , Sistemas de Infusão de Insulina , Pâncreas Artificial , Desenho de Equipamento , Glucose/metabolismo , Humanos , Interface Usuário-Computador
20.
Anat Rec (Hoboken) ; 295(6): 1006-16, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22467529

RESUMO

Narwhal tusks, although well described and characterized within publications, are clouded by contradictory references, which refer to them as both incisors and canines. Vestigial teeth are briefly mentioned in the scientific literature with limited descriptions and no image renderings. This study first examines narwhal maxillary osteoanatomy to determine whether the erupted tusks are best described as incisiform or caniniform teeth. The study also offers evidence to support the evolutionary obsolescence of the vestigial teeth through anatomic, morphologic, and histologic descriptions. Examination of 131 skull samples, including 110 museum skull specimens and 21 harvested skulls, revealed the erupted tusks surrounded by maxillary bone over the entire length of their bone socket insertion, and are thus more accurately termed caniniform or canine teeth. The anatomy, morphology, and development of vestigial teeth in five skull samples are more fully described and documented. Vestigial tooth samples included 14 embedded pairs or individual teeth that were partially exposed or removed from the maxillary bone. Their location was posterior, ventral, and lateral to the tusks, although male vestigial teeth often exfoliate in the mouth lodging between the palatal tissue and underlying maxillary bone. Their myriad morphologies, sizes, and eruption patterns suggest that these teeth are no longer guided by function but rather by random germ cell differentiation and may eventually cease expression entirely. The conclusions reached are that the narwhal tusks are the expression of canine teeth and that vestigial teeth have no apparent functional characteristics and are following a pattern consistent with evolutionary obsolescence.


Assuntos
Dente/anatomia & histologia , Baleias/anatomia & histologia , Animais , Feminino , Masculino , Crânio/anatomia & histologia , Terminologia como Assunto
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