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1.
Dis Aquat Organ ; 155: 87-102, 2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37650480

RESUMO

Between 2010 and 2014, an unusual mortality event (UME) involving bottlenose dolphins Tursiops truncatus occurred in the northern Gulf of Mexico, associated with the Deepwater Horizon oil spill (DWHOS). Cause of death (COD) patterns in bottlenose dolphins since then have not been analyzed, and baseline prevalence data for Brucella ceti and cetacean morbillivirus, 2 pathogens previously reported in this region, are lacking. We analyzed records from bottlenose dolphins stranded in Alabama from 2015 to 2020 with necropsy and histological findings to determine COD (n = 108). This period included another UME in 2019 associated with prolonged freshwater exposure. A subset of individuals that stranded during this period were selected for molecular testing for Brucella spp. and Morbillivirus spp. Causes of death for all age classes were grouped into 6 categories, including (1) human interaction, (2) infectious disease, (3) noninfectious disease (prolonged freshwater exposure and degenerative), (4) trauma, (5) multifactorial, and (6) unknown. Two additional categories unique to perinates included fetal distress and in utero pneumonia. Human interaction was the most common primary COD (19.4%) followed closely by infectious disease (17.6%) and noninfectious disease (freshwater exposure; 13.9%). Brucella was detected in 18.4% of the 98 animals tested, but morbillivirus was not detected in any of the 66 animals tested. Brucella was detected in some moderately to severely decomposed carcasses, indicating that it may be beneficial to test a broad condition range of stranded animals. This study provides valuable information on COD in bottlenose dolphins in Alabama following the DWHOS and is the first to examine baseline prevalence of 2 common pathogens in stranded animals from this region.


Assuntos
Golfinho Nariz-de-Garrafa , Doenças não Transmissíveis , Poluição por Petróleo , Animais , Humanos , Causas de Morte , Alabama/epidemiologia , Doenças não Transmissíveis/veterinária , Prevalência
2.
Adv Mater ; 33(21): e2006863, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33852176

RESUMO

Light-emitting electrochemical cells (LECs) are simple electroluminescent devices comprising an emissive material containing mobile ions sandwiched between two electrodes. The operating mechanism of the LEC involves both ionic and electronic transport, distinguishing it from its more well-known cousin, the organic light-emitting diode (OLED). While OLEDs have become a leading player in commercial displays, LECs have flourished in academic research due to the simple device architecture and unique features of its operating mechanism, inviting exploration of new materials and fabrication strategies. These explorations have brought LECs to an exciting frontier in advanced optoelectronics: flexible and stretchable light-emitting devices. Flexible and stretchable LECs are discussed herein, presenting the LEC system as a robust and fault-tolerant development platform. The engineering of emissive composites is highlighted to control mechanical properties, and how the tolerance of LECs to electrode work function and roughness has enabled the incorporation of new electrode materials to achieve flexibility and stretchability. As part of this story, the solution processability of LECs has led to exciting demonstrations of flexible and printed LECs. An outlook is provided for LECs that builds on these strengths, potentially leading to flexible, stretchable, low-cost devices such as illuminated tags, smart packaging, flexible signage, and wearable illumination.

3.
ACS Appl Mater Interfaces ; 11(34): 31210-31219, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31373786

RESUMO

The emergence of flexible and stretchable optoelectronics has motivated the development of new transparent conductive electrodes (TCEs) to replace conventional brittle indium tin oxide. For modern optoelectronics, these new TCEs should possess six key characteristics: low cost, solution-based processing; high transparency; high electrical conductivity; a smooth surface; mechanical flexibility or stretchability; and scalable, low-cost patterning methods. Among many materials currently being studied, silver nanowires (AgNWs) are one of the most promising, with studies demonstrating AgNW films and composites that exhibit each of the key requirements. However, AgNW-based TCEs reported to date typically fulfill two or three requirements at the same time, and rare are examples of TCEs that fulfill all six requirements simultaneously. Here, we present a straightforward method to fabricate AgNW/polymer composite films that meet all six requirements simultaneously. Our fabrication process embeds a AgNW network patterned using a solution-based wetting-dewetting protocol into a flexible or stretchable polymer, which is then adhered to an elastomeric poly(dimethylsiloxane) substrate. The resulting patterned AgNW/polymer films exhibit ∼85% transmittance with an average sheet resistance of ∼15 Ω/sq, a smooth surface (a root-mean-square surface roughness value of ∼22 nm), and also withstand up to 71% bending strain or 70% stretching strain. We demonstrate the use of these new TCEs in flexible and stretchable alternating current electroluminescent devices that emit light to 20% bending strain and 60% stretching strain.

4.
Ecol Appl ; 29(6): e01947, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31183944

RESUMO

Telemetry is a key, widely used tool to understand marine megafauna distribution, habitat use, behavior, and physiology; however, a critical question remains: "How many animals should be tracked to acquire meaningful data sets?" This question has wide-ranging implications including considerations of statistical power, animal ethics, logistics, and cost. While power analyses can inform sample sizes needed for statistical significance, they require some initial data inputs that are often unavailable. To inform the planning of telemetry and biologging studies of marine megafauna where few or no data are available or where resources are limited, we reviewed the types of information that have been obtained in previously published studies using different sample sizes. We considered sample sizes from one to >100 individuals and synthesized empirical findings, detailing the information that can be gathered with increasing sample sizes. We complement this review with simulations, using real data, to show the impact of sample size when trying to address various research questions in movement ecology of marine megafauna. We also highlight the value of collaborative, synthetic studies to enhance sample sizes and broaden the range, scale, and scope of questions that can be answered.


Assuntos
Ecologia , Ecossistema , Animais , Tamanho da Amostra , Telemetria
5.
Proc Natl Acad Sci U S A ; 115(12): 3072-3077, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29483242

RESUMO

The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals' movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus extrinsic factors remains elusive. We analyze a global dataset of ∼2.8 million locations from >2,600 tracked individuals across 50 marine vertebrates evolutionarily separated by millions of years and using different locomotion modes (fly, swim, walk/paddle). Strikingly, movement patterns show a remarkable convergence, being strongly conserved across species and independent of body length and mass, despite these traits ranging over 10 orders of magnitude among the species studied. This represents a fundamental difference between marine and terrestrial vertebrates not previously identified, likely linked to the reduced costs of locomotion in water. Movement patterns were primarily explained by the interaction between species-specific traits and the habitat(s) they move through, resulting in complex movement patterns when moving close to coasts compared with more predictable patterns when moving in open oceans. This distinct difference may be associated with greater complexity within coastal microhabitats, highlighting a critical role of preferred habitat in shaping marine vertebrate global movements. Efforts to develop understanding of the characteristics of vertebrate movement should consider the habitat(s) through which they move to identify how movement patterns will alter with forecasted severe ocean changes, such as reduced Arctic sea ice cover, sea level rise, and declining oxygen content.


Assuntos
Migração Animal , Bases de Dados Factuais , Oceanos e Mares , Vertebrados , Animais , Ecossistema
6.
Sci Rep ; 8(1): 1648, 2018 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-29374239

RESUMO

Detection and evaluation of inflammatory activity in uveitis is essential to the management of the condition, and yet continues to be largely dependent on subjective clinical measures. Optical coherence tomography (OCT) measurement of vitreous activity is an alternative to clinical vitreous haze scoring and has passed a number of early validation studies. In this study we aimed to evaluate the impact of 'operator factors' on the variability of the technique as part of the validation process, and to help evaluate its suitability for 'real world' use. Vitreous haze index was calculated as a ratio between the reflectivity of the vitreous and of the outer retina in each scan. Different scanning conditions were tested and their effect on the measurement is reported. Our results show that the 'quantitative imaging' technique of OCT-measured vitreous activity had good reliability in normal subjects under a range of 'real world' conditions, such as when the operator changes the averaging value. The technique was however vulnerable to highly inaccurate focussing or abnormal downward displacement of the image. OCT-based quantification of vitreous activity is a promising alternative to current subjective clinical estimates, with sufficient 'tolerance' to be used in routine clinical practice as well as clinical trials.


Assuntos
Tomografia de Coerência Óptica/métodos , Uveíte/diagnóstico por imagem , Corpo Vítreo/patologia , Voluntários Saudáveis , Humanos , Reprodutibilidade dos Testes
7.
Rapid Commun Mass Spectrom ; 30(24): 2594-2600, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-27709696

RESUMO

RATIONALE: Extraction of lipids from tissues prior to carbon stable isotope analysis (SIA) has become a common practice, despite a lack of species-specific data to indicate when lipid extraction is needed. Marine invertebrates, including bivalves, are known to store carbon as glycogen and less in the form of lipids than other species, potentially reducing the need for lipid extraction even when C:N values are above 3.5, a value that previous studies suggest indicates a need for lipid extraction of animal tissues. METHODS: We investigated the need for lipid extraction on individual tissues (adductor muscle, gut gland, gill) and whole tissue of a glycogen-storing species, the oyster Crassostrea virginica. Bulk and lipid-extracted samples were analyzed for their C and N stable isotope ratios by continuous flow isotope ratio mass spectrometry (IRMS). Samples were analyzed on a 20-20 isotope ratio mass spectrometer (PDZ Europa) after combustion in an elemental analyzer (PDZ Europa Automatic Analyzer-Gas Solid Liquid). RESULTS: Although the C:N values for most bulk (unextracted) tissue samples were greater than 3.5, the lipid-extracted δ13 C values did not differ from the bulk values. Lipid extraction, however, affected δ15 N values in all tissue types except adductor muscle, indicating that separate SIA may be required when tissues are lipid extracted. CONCLUSIONS: These data demonstrate that it is not necessary to lipid extract oyster tissues in all cases, and that C:N thresholds for lipid extraction in other species may not be reliable for organisms such as oysters that store glycogen. Our data indicate that minimizing unnecessary lipid extraction through preliminary testing will save researchers time and expense by avoiding superfluous sample handling, reducing concern over secondary effects on data quality, and reducing the costs of reagents and additional separate stable isotope analysis to ensure analytical accuracy. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Isótopos de Carbono/análise , Glicogênio/análise , Lipídeos/química , Isótopos de Nitrogênio/análise , Ostreidae/química , Frutos do Mar/análise , Animais , Lipídeos/isolamento & purificação , Espectrometria de Massas
8.
Langmuir ; 32(40): 10206-10212, 2016 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-27653527

RESUMO

Transparent butyl rubber is a new elastomer that has the potential to revolutionize stretchable electronics due to its intrinsically low gas permeability. Encapsulating organic electronic materials and devices with transparent butyl rubber protects them from problematic degradation due to oxygen and moisture, preventing premature device failure and enabling the fabrication of stretchable organic electronic devices with practical lifetimes. Here, we report a methodology to alter the surface chemistry of transparent butyl rubber to advance this material from acting as a simple device encapsulant to functioning as a substrate primed for direct device fabrication on its surface. We demonstrate a combination of plasma and chemical treatment to deposit a hydrophilic silicate layer on the transparent butyl rubber surface to create a new layered composite that combines Si-OH surface chemistry with the favorable gas-barrier properties of bulk transparent butyl rubber. We demonstrate that these surface Si-OH groups react with organosilanes to form self-assembled monolayers necessary for the deposition of electronic materials, and furthermore demonstrate the fabrication of stretchable gold wires using nanotransfer printing of gold films onto transparent butyl rubber modified with a thiol-terminated self-assembled monolayer. The surface modification of transparent butyl rubber establishes this material as an important new elastomer for stretchable electronics and opens the way to robust, stretchable devices.

9.
ACS Appl Mater Interfaces ; 7(37): 20745-52, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26302030

RESUMO

We demonstrate a simple, low-cost, and green approach to deposit a microstructured coating on the silicone elastomer polydimethylsiloxane (PDMS) that can be coated with gold to produce highly stretchable and conductive films. The microstructured coating is fabricated using an aqueous emulsion of poly(vinyl acetate) (PVAc): common, commercially available white glue. The aqueous glue emulsion self-assembles on the PDMS surface to generate clustered PVAc globules, which can be conformally coated with gold. The microstructured surface provides numerous defect sites that localize strain when the structure is stretched, resulting in the initiation of numerous microcracks. As the structure is further elongated, the microcracks interact with one another, preventing long-range crack propagation and thus preserving the conduction pathway. The resistance of PDMS/glue/gold structures remains remarkably low (23 times the initial resistance) up to 65% elongation, making these structure useful as stretchable interconnects. Decreasing the concentration of the PVAc aqueous emulsion reduces the density of defect sites of the microstructure, which increases the change in resistance of the gold films with stretching. In this way, we can tune the resistance changes of the PDMS/glue/gold structures and increase their sensitivity to strain. We demonstrate the use of these structures as wearable, soft strain sensors.


Assuntos
Custos e Análise de Custo , Ouro/química , Ouro/economia , Dimetilpolisiloxanos/química , Vidro/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Difração de Raios X
10.
ACS Appl Mater Interfaces ; 5(20): 10165-72, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24007382

RESUMO

We present new flexible, transparent, and conductive coatings composed of an annealed silver nanowire network embedded in a polyurethane optical adhesive. These coatings can be applied to rigid glass substrates as well as to flexible polyethylene terephthalate (PET) plastic and elastomeric polydimethylsiloxane (PDMS) substrates to produce highly flexible transparent conductive electrodes. The coatings are as conductive and transparent as indium tin oxide (ITO) films on glass, but they remain conductive at high bending strains and are more durable to marring and scratching than ITO. Coatings on PDMS withstand up to 76% tensile strain and 250 bending cycles of 15% strain with a negligible increase in electrical resistance. Since the silver nanowire network is embedded at the surface of the optical adhesive, these coatings also provide a smooth surface (root mean squared surface roughness<10 nm), making them suitable as transparent conducting electrodes in flexible light-emitting electrochemical cells. These devices continue to emit light even while being bent to radii as low as 1.5 mm and perform as well as unstrained devices after 20 bending cycles of 25% tensile strain.


Assuntos
Eletrônica , Nanofios/química , Prata/química , Dimetilpolisiloxanos/química , Técnicas Eletroquímicas , Eletrodos , Vidro/química , Polietilenotereftalatos/química , Resistência à Tração , Compostos de Estanho/química
11.
J Vet Pharmacol Ther ; 36(5): 441-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23301502

RESUMO

Equine herpes myeloencephalopathy, resulting from equine herpes virus type 1 (EHV-1) infection, is associated with substantial morbidity and mortality in the horse. As compared to other antiviral drugs, such as acyclovir, ganciclovir has enhanced potency against EHV-1. This study investigated the pharmacokinetics of ganciclovir and its oral prodrug, valganciclovir, in six adult horses in a randomized cross-over design. Ganciclovir sodium was administered intravenously as a slow bolus at a dose of 2.5 mg/kg, and valganciclovir was administered orally at a dose of 1800 mg per horse. Intravenously administered ganciclovir disposition was best described by a three-compartment model with a prolonged terminal half-life of 72 ± 9 h. Following the oral administration of valganciclovir, the mean observed maximum serum ganciclovir concentration was 0.58 ± 0.37 µg/mL, and bioavailability of ganciclovir from oral valganciclovir was 41 ± 20%. Superposition predicted that oral dosing of 1800-mg valganciclovir two times daily would fail to produce and maintain effective plasma concentrations of ganciclovir. However, superposition suggested that i.v. administration of ganciclovir at 2.5 mg/kg every 8 h for 24 h followed by maintenance dosing of 2.5 mg/kg every 12 h would maintain effective ganciclovir serum concentrations in most horses throughout the dosing interval.


Assuntos
Antivirais/farmacocinética , Ganciclovir/análogos & derivados , Ganciclovir/farmacocinética , Administração Oral , Animais , Antivirais/administração & dosagem , Antivirais/sangue , Feminino , Ganciclovir/administração & dosagem , Ganciclovir/sangue , Cavalos , Injeções Intravenosas/veterinária , Masculino , Valganciclovir
12.
Adv Mater ; 24(20): 2673-8, 2012 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-22451224

RESUMO

Dispersing an ionic transition metal complex into an elastomeric matrix enables the fabrication of intrinsically stretchable light-emitting devices that possess large emission areas (∼175 mm(2)) and tolerate linear strains up to 27% and repetitive cycles of 15% strain. This work demonstrates the suitability of this approach to new applications in conformable lighting that require uniform, diffuse light emission over large areas.


Assuntos
Eletrônica , Luz , Complexos de Coordenação/química , Dimetilpolisiloxanos/química , Técnicas Eletroquímicas/instrumentação , Polimetil Metacrilato/química , Rutênio/química , Elementos de Transição/química
14.
Br J Anaesth ; 91(3): 424-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12925485

RESUMO

BACKGROUND: The pro- and anti-inflammatory cytokine balance has been implicated in outcome from inflammatory conditions, and cardiopulmonary bypass is associated with a marked inflammatory response. Interleukin-10 (IL-10) is an anti-inflammatory cytokine and levels have been shown to be highest in those patients who develop sepsis after trauma or surgery. IL-10 levels vary between individuals and genotype may dictate the IL-10 response. We therefore investigated IL-10 genotype, circulating IL-10 concentrations and outcome in terms of organ dysfunction 24 h after cardiopulmonary bypass. METHODS: Blood samples were obtained from 150 patients before, and 3, and 24 h after cardiopulmonary bypass. IL-10 was measured by enzyme immunoassay. The single nucleotide polymorphism at -1082 base pairs was detected by restriction fragment length polymorphism analysis. Post-bypass organ system dysfunction was defined prospectively. RESULTS: IL-10 concentrations were increased 3 h after bypass (P<0.0001) and were still increased at 24 h (P<0.0001). Homozygosity for the G allele was associated with lower median (range) maximal IL-10 levels at 3 h (44 (13-136) pg ml(-1)) compared with the A allele (118 (39-472) pg ml(-1); P=0.042). Those patients who developed at least one organ dysfunction (n=33) had higher IL-10 levels 3 h after surgery (242 (18-694) pg ml(-1)) compared with those without organ dysfunction (77 (7-586) pg ml(-1); P=0.001, n=117). CONCLUSIONS: The G allele of the -1082 base pair single nucleotide polymorphism in the IL-10 gene is associated with lower IL-10 release after cardiopulmonary bypass. High levels of IL-10 secretion are associated with organ dysfunction 24 h after surgery.


Assuntos
Ponte Cardiopulmonar , Genótipo , Interleucina-10/genética , Adulto , Idoso , Biomarcadores/sangue , Ponte de Artéria Coronária , Feminino , Humanos , Interleucina-10/sangue , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Complicações Pós-Operatórias/sangue , Período Pós-Operatório , Estudos Prospectivos
15.
J Can Dent Assoc ; 67(10): 594, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11737984

RESUMO

This article identifies certain syndromes of the head and neck, which a dentist may see in clinical practice, and relates these syndromes to their sites of mutation on involved genes. This paper is timely with the near completion of the Human Genome Project, the mapping of the entire human genetic material. Knowing the site of the genetic lesion is important in helping clinicians understand the genetic basis for these conditions, and may help in our future understanding of remedies and treatments.


Assuntos
Anormalidades Craniofaciais/genética , Anormalidades Dentárias/genética , Amelogênese Imperfeita/genética , Anodontia/genética , Síndrome do Nevo Basocelular/genética , Cromossomos Humanos Par 4 , Cromossomos Humanos Par 6 , Cromossomos Humanos Par 8 , Cromossomos Humanos Par 9 , Fenda Labial/genética , Displasia Cleidocraniana/genética , Dentinogênese Imperfeita/genética , Feminino , Humanos , Masculino , Disostose Mandibulofacial/genética , Mutação , Osteopetrose/genética , Cromossomos Sexuais , Síndrome
18.
J Oral Maxillofac Surg ; 57(7): 801-5; discussion 805-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10416626

RESUMO

PURPOSE: This study describes an alternate approach for harvesting cancellous bone from the anterior iliac crest and quantifies the amount of bone removed using a power-driven trephine without the need for an open procedure. The safety of this technique is also evaluated. MATERIALS AND METHODS: Twenty-five adult cadavers were used to determine the volume and weight of bone that could be harvested using a motorized trephine. A total of 50 anterior iliac crests were sampled. Core samples of cancellous bone were measured, weighed, and the volume calculated. The harvested sites were then dissected and evaluated for perforations. These data were compared with the measurement of the first 40 consecutive cores trephined from patients requiring grafts. RESULTS: The bone harvested took the form of a compact core measuring, on average, 33.5 mm in length and 4.0 mm in diameter. The average weight of each core was 0.44 g, and the average volume was 0.42 cm3. Perforation to the medial aspect occurred in 4 of 50 hips, and lateral perforations occurred in 7 of 50 hips. The greatest number of perforations occurred at depths greater than 30 mm and were found in the most atrophic cadavers. The 40 cores obtained from patients averaged 34.1 mm in length and 0.46 g in weight. The average volume per core was 0.45 cm3. CONCLUSIONS: The amount of trephinated autogenous cancellous bone procurable by means of a motor-driven trephine is suitable for cases of sinus lifting or to fill an alveolar cleft defect. Although the yield of cadaveric bone is slightly less than the amount obtainable from patients, it is a useful model to evaluate potential complications and estimate yields.


Assuntos
Transplante Ósseo/instrumentação , Osso e Ossos/anatomia & histologia , Osteotomia/instrumentação , Adulto , Idoso , Atrofia , Transplante Ósseo/efeitos adversos , Osso e Ossos/patologia , Cadáver , Dissecação , Feminino , Humanos , Ílio/cirurgia , Masculino , Osteotomia/efeitos adversos , Periósteo/lesões
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