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1.
Philos Trans A Math Phys Eng Sci ; 378(2182): 20190581, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32921237

RESUMO

While both non-destructive evaluation (NDE) and structural health monitoring (SHM) share the objective of damage detection and identification in structures, they are distinct in many respects. This paper will discuss the differences and commonalities and consider ultrasonic/guided-wave inspection as a technology at the interface of the two methodologies. It will discuss how data-based/machine learning analysis provides a powerful approach to ultrasonic NDE/SHM in terms of the available algorithms, and more generally, how different techniques can accommodate the very substantial quantities of data that are provided by modern monitoring campaigns. Several machine learning methods will be illustrated using case studies of composite structure monitoring and will consider the challenges of high-dimensional feature data available from sensing technologies like autonomous robotic ultrasonic inspection. This article is part of the theme issue 'Advanced electromagnetic non-destructive evaluation and smart monitoring'.


Assuntos
Engenharia , Aprendizado de Máquina , Ultrassom/métodos , Algoritmos , Teorema de Bayes , Compressão de Dados , Engenharia/estatística & dados numéricos , Humanos , Instalações Industriais e de Manufatura , Análise de Regressão , Robótica , Processamento de Sinais Assistido por Computador , Ultrassom/estatística & dados numéricos
2.
Ann Oncol ; 28(7): 1554-1559, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28379307

RESUMO

BACKGROUND: T-cell prolymphocytic leukemia (T-PLL) is a rare and aggressive disease. In this study, we report our experience from 119 patients with T-PLL. PATIENTS AND METHODS: We reviewed the clinico-pathologic records of 119 consecutive patients with T-PLL, who presented to our institution between 1990 and 2016. RESULTS: One hundred and nineteen patients with T-PLL were analysed. Complex karyotype and aberrations in chromosome 14 were seen in 65% and 52% patients, respectively. Seventy-five patients (63%) were previously untreated and 43 (37%) were initially treated outside our institution. Sixty-three previously untreated patients (84%) received frontline therapies. Overall, 95 patients (80%) have died. Median overall survival (OS) from diagnosis was 19 months [95% confidence interval (CI) 16-26 months]. Using recursive partitioning (RP), we found that patients with hemoglobin < 9.3 g/dl, lactate dehydrogenase (LDH) ≥ 1668 IU/l, white blood cell ≥ 208 K/l and ß2M ≥ 8 mg/l had significantly inferior OS and patients with hemoglobin < 9.3 g/dl had inferior progression-free survival (PFS). In multivariate analysis, we identified that presence of pleural effusion [hazard ratio (HR) 2.08 (95% CI 1.11-3.9); P = 0.02], high LDH (≥ 1668 IU/l) [HR 2.5 (95% CI 1.20-4.24); P < 0.001)], and low hemoglobin (< 9.3 g/dl) [HR 0.33 (95% CI 0.14-0.75); P = 0.008] were associated with shorter OS. Fifty-five previously untreated patients received treatment with an alemtuzumab-based regimen (42 monotherapy and 13 combination with pentostatin). Overall response rate, complete remission rate (CR) for single-agent alemtuzumab and alemtuzumab combined with pentostatin were 83%, 66% and 82%, 73% respectively. In patients who achieved initial CR, stem cell transplantation was not associated with longer PFS and OS. CONCLUSION: Outcomes in T-PLL remain poor. Multicenter collaborative effort is required to conduct prospective studies.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia Prolinfocítica de Células T/terapia , Transplante de Células-Tronco , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Progressão da Doença , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Cariótipo , Leucemia Prolinfocítica de Células T/genética , Leucemia Prolinfocítica de Células T/mortalidade , Leucemia Prolinfocítica de Células T/patologia , Prontuários Médicos , Análise Multivariada , Modelos de Riscos Proporcionais , Recidiva , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Transplante de Células-Tronco/efeitos adversos , Transplante de Células-Tronco/mortalidade , Texas , Fatores de Tempo , Resultado do Tratamento
3.
J Evol Biol ; 29(3): 594-601, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26679743

RESUMO

Ecological diversification into new environments presents new mechanical challenges for locomotion. An extreme example of this is the transition from a terrestrial to an aquatic lifestyle. Here, we examine the implications of life in a neutrally buoyant environment on adaptations of the axial skeleton to evolutionary increases in body size. On land, mammals must use their thoracolumbar vertebral column for body support against gravity and thus exhibit increasing stabilization of the trunk as body size increases. Conversely, in water, the role of the axial skeleton in body support is reduced, and, in aquatic mammals, the vertebral column functions primarily in locomotion. Therefore, we hypothesize that the allometric stabilization associated with increasing body size in terrestrial mammals will be minimized in secondarily aquatic mammals. We test this by comparing the scaling exponent (slope) of vertebral measures from 57 terrestrial species (23 felids, 34 bovids) to 23 semi-aquatic species (pinnipeds), using phylogenetically corrected regressions. Terrestrial taxa meet predictions of allometric stabilization, with posterior vertebral column (lumbar region) shortening, increased vertebral height compared to width, and shorter, more disc-shaped centra. In contrast, pinniped vertebral proportions (e.g. length, width, height) scale with isometry, and in some cases, centra even become more spool-shaped with increasing size, suggesting increased flexibility. Our results demonstrate that evolution of a secondarily aquatic lifestyle has modified the mechanical constraints associated with evolutionary increases in body size, relative to terrestrial taxa.


Assuntos
Mamíferos/anatomia & histologia , Coluna Vertebral/anatomia & histologia , Adaptação Fisiológica , Animais , Evolução Biológica , Tamanho Corporal , Caniformia/anatomia & histologia , Ecossistema , Felidae/anatomia & histologia , Filogenia
4.
J Evol Biol ; 28(8): 1516-25, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26075837

RESUMO

The evolution of body mass is a fundamental topic in evolutionary biology, because it is closely linked to manifold life history and ecological traits and is readily estimable for many extinct taxa. In this study, we examine patterns of body mass evolution in Felidae (Placentalia, Carnivora) to assess the effects of phylogeny, mode of evolution, and the relationship between body mass and prey choice in this charismatic mammalian clade. Our data set includes 39 extant and 26 extinct taxa, with published body mass data supplemented by estimates based on condylobasal length. These data were run through 'SURFACE' and 'bayou' to test for patterns of body mass evolution and convergence between taxa. Body masses of felids are significantly different among prey choice groupings (small, mixed and large). We find that body mass evolution in cats is strongly influenced by phylogeny, but different patterns emerged depending on inclusion of extinct taxa and assumptions about branch lengths. A single Ornstein-Uhlenbeck optimum best explains the distribution of body masses when first-occurrence data were used for the fossil taxa. However, when mean occurrence dates or last known occurrence dates were used, two selective optima for felid body mass were recovered in most analyses: a small optimum around 5 kg and a large one around 100 kg. Across living and extinct cats, we infer repeated evolutionary convergences towards both of these optima, but, likely due to biased extinction of large taxa, our results shift to supporting a Brownian motion model when only extant taxa are included in analyses.


Assuntos
Tamanho Corporal/genética , Felidae/anatomia & histologia , Felidae/fisiologia , Filogenia , Animais , Evolução Biológica , Gatos , Extinção Biológica , Fósseis , Comportamento Predatório
5.
Water Sci Technol ; 70(11): 1888-96, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25500478

RESUMO

Quantifying groundwater availability depends upon sound methods and the use of integrated models. To determine availability or sustainable yield, the influence of scientific uncertainty from key sources, such as anthropogenic recharge, must be considered. This study evaluates uncertainty in recharge interpretations on the modeled available water balance for an urban case in Texas, USA. Analyses are completed using the Groundwater Decision Support System, which is a research code-base for an integrated modeling. The case study develops spatially and temporally resolved recharge interpretations based on NEXRAD precipitation and detailed land use data. Results demonstrate the implications of scientific uncertainty as it influences recommendations for policy and urban water management decisions that are based on modeled outputs. Geospatial methods account for spatial and temporal components and can be replicated for other systems. These methods are also useful for resolving uncertainty in relation to the influence of urbanization on recharge through land use change.


Assuntos
Técnicas de Apoio para a Decisão , Água Subterrânea , Modelos Teóricos , Incerteza , Abastecimento de Água , Clima , Humanos , Texas , Movimentos da Água
6.
Artigo em Inglês | MEDLINE | ID: mdl-38829751

RESUMO

In Non-Destructive Evaluation (NDE), accurately characterizing defects within components relies on accurate sizing and localization to evaluate the severity or criticality of defects. This study presents for the first time a deep learning methodology using 3-Dimensional (3D) U-Net to localize and size defects in Carbon Fibre Reinforced Polymer (CFRP) composites through volumetric segmentation of ultrasonic testing data. Using a previously developed approach, synthetic training data closely representative of experimental data was used for the automatic generation of ground truth segmentation masks. The model's performance was compared to the conventional amplitude 6 dB drop analysis method used in industry against ultrasonic defect responses from 40 defects fabricated in CFRP components. The results showed good agreement with the 6 dB drop method for in-plane localization and excellent through-thickness localization, with Mean Absolute Errors (MAE) of 0.57 mm and 0.08 mm, respectively. Initial sizing results consistently oversized defects with a 55% higher mean average error than the 6 dB drop method. However, when a correction factor was applied to account for variation between the experimental and synthetic domains the final sizing accuracy resulted in a 35% reduction in MAE compared to the 6 dB drop technique. By working with volumetric ultrasonic data (as opposed to 2D images) this approach reduces pre-processing (such as signal gating) and allows for the generation of 3D defect masks which can be used for the generation of computer aided design files; greatly reducing the qualification reporting burden of NDE operators.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38215332

RESUMO

This study presents a deep-learning (DL) methodology using 3-D convolutional neural networks (CNNs) to detect defects in carbon fiber-reinforced polymer (CFRP) composites through volumetric ultrasonic testing (UT) data. Acquiring large amounts of ultrasonic training data experimentally is expensive and time-consuming. To address this issue, a synthetic data generation method was extended to incorporate volumetric data. By preserving the complete volumetric data, complex preprocessing is reduced, and the model can utilize spatial and temporal information that is lost during imaging. This enables the model to utilize important features that might be overlooked otherwise. The performance of three architectures was compared. The first architecture is prevalent in the literature for the classification of volumetric datasets. The second demonstrated a hand-designed approach to architecture design, with modifications to the first architecture to address the challenges of this specific task. A key modification was the use of cuboidal kernels to account for the large aspect ratios seen in ultrasonic data. The third architecture was discovered through neural architecture search (NAS) from a modified 3-D residual neural network (ResNet) search space. In addition, domain-specific augmentation methods were incorporated during training, resulting in significant improvements in model performance, with a mean accuracy improvement of 22.4% on the discovered architecture. The discovered architecture demonstrated the best performance with a mean accuracy increase of 7.9% over the second-best model. It was able to consistently detect all defects while maintaining a model size smaller than most 2-D ResNets. Each model had an inference time of less than 0.5 s, making them efficient for the interpretation of large amounts of data.

8.
J Psychiatr Res ; 177: 102-108, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39002531

RESUMO

OBJECTIVES: This study examined sex differences for health risk factors as potential mediators in the association between posttraumatic stress disorder (PTSD) and cardiovascular disease (CVD). METHODS: Secondary data from the 2012-2013 National Epidemiological Survey on Alcohol and Related Conditions Wave 3 was used. This cross-sectional survey contains a nationally representative sample of 36,309 U.S. adults (nfemales = 20,447, Mage = 47.16, 95% CI = [46.74, 47,57]; nmales = 15,682, Mage = 45.88, 95% CI = [45.42, 46.34]). Natural effect models and logistic regression analyses were conducted to evaluate health risk factors (smoking, substance use, low physical activity, high body mass index [BMI], binge eating, and multiple health risk factors) as potential mediators for the PTSD-CVD relationship in females and males. RESULTS: High BMI (indirect AOR = 1.05, 95% CI = [1.02, 1.07]) and substance use (indirect AOR = 0.93, 95% CI = [0.88, 0.98], p = 0.005) were potential mediators in females and males respectively. Binge eating, smoking, and low physical activity were not mediators in either sex. The number of health risk factors was also a potential mediator in females (indirect AOR = 1.12, 95% CI = [1.07, 1.19], p = <0.001) though not males (indirect AOR = 1.09, 95% CI = [1.00, 1.19], p = .059). CONCLUSIONS: The results inform prevention strategies, such as screening for health risk factors to mitigate the adverse effect of PTSD on CVD risk. Findings also inform important directions for future longitudinal research to establish causal pathways.

9.
Ultrasonics ; 140: 107313, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38603904

RESUMO

The use of Carbon Fibre Reinforced Plastic (CFRP) composite materials for critical components has significantly surged within the energy and aerospace industry. With this rapid increase in deployment, reliable post-manufacturing Non-Destructive Evaluation (NDE) is critical for verifying the mechanical integrity of manufactured components. To this end, an automated Ultrasonic Testing (UT) NDE process delivered by an industrial manipulator was developed, greatly increasing the measurement speed, repeatability, and locational precision, while increasing the throughput of data generated by the selected NDE modality. Data interpretation of UT signals presents a current bottleneck, as it is still predominantly performed manually in industrial settings. To reduce the interpretation time and minimise human error, this paper presents a two-stage automated NDE evaluation pipeline consisting of a) an intelligent gating process and b) an autoencoder (AE) defect detector. Both stages are based on an unsupervised method, leveraging density-based spatial clustering of applications with noise clustering method for robust automated gating and undefective UT data for the training of the AE architecture. The AE network trained on ultrasonic B-scan data was tested for performance on a set of reference CFRP samples with embedded and manufactured defects. The developed model is rapid during inference, processing over 2000 ultrasonic B-scans in 1.26 s with the area under the receiver operating characteristic curve of 0.922 in simple and 0.879 in complex geometry samples. The benefits and shortcomings of the presented methods are discussed, and uncertainties associated with the reported results are evaluated.

10.
Am J Hematol ; 88(9): 784-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23757320

RESUMO

Aberrant promoter DNA methylation is a well-described mechanism of leukemogenesis within hematologic malignancies, including acute lymphoblastic leukemia (ALL). However, the importance of methylation patterns among the adolescent and young adult (AYA) ALL population has not been well established. DNA methylation of 18 candidate genes in 33 AYA ALL patients was analyzed at diagnosis and during treatment, to evaluate the frequency and clinical relevance of aberrant methylation in an AYA population treated on a uniform therapeutic regimen. Of 16 informative genes, there was a median of 6 methylated genes per AYA ALL patient. Correlations were identified between increasing number of methylated genes with male sex (P = 0.04), increased white blood cell (WBC) count (P = 0.04) and increased bone-marrow blast percentage (P = 0.04). Increasing age was associated with EPHA5 methylation (P = 0.05). Overall, patients experienced favorable outcomes with median survival that was not reached. On univariate analysis, methylation of CYP1B1 was associated with worse overall survival (HR 10.7, 95% CI 1.3-87.6, P = 0.03), disease-free survival (HR 3.7, 95% CI 1.1-9.2, P = 0.04) and correlated with decreased CYP1B1 gene expression. A significant incidence of methylation within the AYA ALL population was identified, with increased methylation associated with distinct clinicopathologic features including male gender and elevated WBC count. Our results suggest aberrant methylation among AYA patients is frequent, and may provide a common pathogenic mechanism. The inferior outcome identified with methylation of the cytochrome p450 gene CYP1B1, an enzyme involved in drug metabolism and steroid synthesis, warrants further investigation.


Assuntos
Hidrocarboneto de Aril Hidroxilases/metabolismo , Metilação de DNA , DNA/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Adolescente , Adulto , Hidrocarboneto de Aril Hidroxilases/genética , Citocromo P-450 CYP1B1 , DNA/genética , Feminino , Expressão Gênica , Humanos , Contagem de Leucócitos , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Regiões Promotoras Genéticas , Receptor EphA5/genética , Receptor EphA5/metabolismo , Fatores Sexuais , Análise de Sobrevida
11.
J Environ Qual ; 42(5): 1480-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24216425

RESUMO

Low-grade weirs are controlled surface drainage management structures that are being advocated for improving water quality of downstream ecosystems within agricultural landscapes. Low-grade weirs are small controlled drainage structures that are placed in series in an agricultural drainage ditch to create biogeochemical conditions for enhanced nutrient retention but also to slow runoff velocities and encourage sedimentation. This study evaluated eight low-grade weirs for sediment and P accumulation in agricultural drainage ditches 1 yr after installation. On average, sediment (weir: 54 ± 25cm; reference: 13 ± 7 cm; ≤ 0.001) and water (weir: 9 ± 7cm; reference: 1.16 ± 2 cm; ≤ 0.05) depth was greater upstream of weirs when compared within ditch references sites. There were no significant differences in total P concentrations of sediments or between any P fractions between 1-yr-old weirs and their respective references. Bioavailability ratios of P (i.e., the ratio of potentially bioavailable to nonbioavailable P fractions) were also found to be similar between weir and reference sites. Based on these results, weirs increase the hydrological capacity of drainage ditches and significantly retain more sediment and P within the drainage ditch within 1 yr of construction. Future research will examine temporal changes in weir sediments and associated P concentrations to aid our understanding of how maintenance of weirs should occur to maximize physical and chemical characteristics for greatest sediment and P retention.


Assuntos
Fósforo , Poluentes Químicos da Água , Agricultura , Drenagem , Meio Ambiente , Sedimentos Geológicos/química , Fósforo/química , Movimentos da Água
12.
J Fish Biol ; 83(3): 574-87, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23991875

RESUMO

There were 479 reported whale shark Rhincodon typus encounters between 1999 and 2011 at the island of Utila, which forms part of the Meso-American Barrier Reef System (MBRS) in the western Caribbean Sea. The majority of R. typus were found to feed on small bait fish associated with various tuna species. Ninety-five individual R. typus, ranging from 2 to 11 m total length (LT ), were identified through their unique spot patterns. A significant male bias (65%) was present. There was no significant difference between the mean ± s.d. LT of female (6·66 ± 1·65 m) and male (6·25 ± 1·60 m) R. typus. Most R. typus were transient to Utila, with 78% sighted only within a single calendar year, although some individuals were sighted in up to 5 years. Mean residency time was modelled to be 11·76 days using maximum likelihood methods.


Assuntos
Tubarões , Animais , Região do Caribe , Demografia , Feminino , Honduras , Ilhas , Masculino
13.
World Neurosurg ; 172: e581-e584, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36716855

RESUMO

INTRODUCTION: Neurosurgeons must master microanatomy and its variants that occur at the skull base. To the best of our knowledge, we describe a previously unreported dural venous sinus (DVS) within the anterior petroclinoid fold and discuss its potential surgical relevance. METHODS: Fifteen latex-injected human cadaveric heads (30 sides) underwent skull base dissection using a surgical microscope. The anterior petroclinoid fold was opened in search of evidence of an embedded DVS. When identified, this sinus was documented, photographed, and measured with microcalipers. RESULTS: An anterior petroclinoid sinus (APCS) was identified in 67% of sides. These DVSs had a mean diameter of 0.65 mm and a length ranging from 8 to 15 mm (mean: 12.5 mm). The APCS ran from the anterior aspect of the cavernous sinus, arising just lateral (60%), posterior (20%), or medial (20%) to the anterior clinoid process, to the superior petrosal sinus (65%) or the posterior aspect of the cavernous sinus (35%), at the level of the posterior clinoid process. Along the course of the APCS, the oculomotor nerve was located medially at the oculomotor porus. Although slightly more common and larger on the right side, there was no statistically significant side difference. CONCLUSIONS: An improved knowledge of variant DVSs can lower the risk of intraoperative complications and increase our understanding of the venous outflow from the cavernous sinus. Future neuroimaging techniques might also seek to identify the APCS. This is the first description of a DVS contained within the anterior petroclinoid fold.


Assuntos
Seio Cavernoso , Base do Crânio , Humanos , Base do Crânio/diagnóstico por imagem , Base do Crânio/cirurgia , Base do Crânio/anatomia & histologia , Cavidades Cranianas/diagnóstico por imagem , Cavidades Cranianas/cirurgia , Nervo Oculomotor , Osso Esfenoide/anatomia & histologia , Seio Cavernoso/cirurgia , Cadáver
14.
J Fish Biol ; 80(5): 1361-79, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497388

RESUMO

The use of photography to discriminate between individuals in a population using natural markings or aberrations is increasingly being utilized to support field research on elasmobranchs. This non-intrusive method has facilitated investigation of a wide variety of subjects including population composition, abundance estimates, residency and movement, demography and social behaviours. Here the first detailed review of photo-identification as a research technique for sharks and rays is provided, and its assumptions, current applications and potential highlighted. The limitations and practical considerations of photographic studies are also investigated with recommendations on initial survey design and ongoing data collection using current technology. Future directions are also explored with an emphasis on a move towards standardized approaches and automated recognition programmes to facilitate global collaborative work.


Assuntos
Sistemas de Identificação Animal , Fotografação , Tubarões , Rajidae , Animais , Fotografação/normas
15.
J Fish Biol ; 80(5): 1075-119, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497374

RESUMO

The Mobulidae are zooplanktivorous elasmobranchs comprising two recognized species of manta rays (Manta spp.) and nine recognized species of devil rays (Mobula spp.). They are found circumglobally in tropical, subtropical and temperate coastal waters. Although mobulids have been recorded for over 400 years, critical knowledge gaps still compromise the ability to assess the status of these species. On the basis of a review of 263 publications, a comparative synthesis of the biology and ecology of mobulids was conducted to examine their evolution, taxonomy, distribution, population trends, movements and aggregation, reproduction, growth and longevity, feeding, natural mortality and direct and indirect anthropogenic threats. There has been a marked increase in the number of published studies on mobulids since c. 1990, particularly for the genus Manta, although the genus Mobula remains poorly understood. Mobulid species have many common biological characteristics although their ecologies appear to be species-specific, and sometimes region-specific. Movement studies suggest that mobulids are highly mobile and have the potential to rapidly travel large distances. Fishing pressure is the major threat to many mobulid populations, with current levels of exploitation in target fisheries unlikely to be sustainable. Advances in the fields of population genetics, acoustic and satellite tracking, and stable-isotope and fatty-acid analyses will provide new insights into the biology and ecology of these species. Future research should focus on the uncertain taxonomy of mobulid species, the degree of overlap between their large-scale movement and human activities such as fisheries and pollution, and the need for management of inter-jurisdictional fisheries in developing nations to ensure their long-term sustainability. Closer collaboration among researchers worldwide is necessary to ensure standardized sampling and modelling methodologies to underpin global population estimates and status.


Assuntos
Conservação dos Recursos Naturais , Elasmobrânquios/crescimento & desenvolvimento , Elasmobrânquios/fisiologia , Animais , Elasmobrânquios/classificação , Pesqueiros , Atividades Humanas , Dinâmica Populacional
16.
Lab Anim ; 56(6): 540-549, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35850552

RESUMO

The objective of this study was to describe prolonged surgical anaesthesia and recovery in fire salamanders (Salamandra salamandra) using tricaine methanesulfonate (MS-222). A total of 14 salamanders were anaesthetised for electromyography wire implantation. Sodium bicarbonate buffered solutions (0.5-4 g l-1) of MS-222 were prepared (adjusted to pH 7.0). Anaesthesia was induced by partial immersion in pre-oxygenated 3 g l-1 solution for 20 min. Buprenorphine (0.5 mg kg-1) was administered subcutaneously. During microsurgery, heart rate (HR), solution pH and temperature were recorded. Reflectance pulse oximeter (SpO2) (Masimo Rad-57) was recorded in two salamanders. Anaesthetic plane and MS-222 pH stability (pH 7.6) were maintained by renewing administration of oxygenated MS-222 solution (0.5-3 g l-1) onto swabs that partially covered the body. Recovery started at the end of surgery (MS-222 0 g l-1). Postoperatively, salamanders were given oral meloxicam (0.2 mg kg-1). Mean time for loss of righting reflex during induction was 13.7 ± 2.2 min. Duration of anaesthesia and time to recovery were 111 ± 24.2 and 31 ± 10.3 min, respectively. Due to complications, two salamanders did not recover. Baseline HR was 67.4 ± 34.5 beats/min, and it decreased significantly until recovery (p ≤ 0.0001). In two salamanders, baseline SpO2 was 85.5% ± 14.5, SpO2 during surgery was 61% ± 6.4, improving to 80.5% ± 2.1 on recovery.In conclusion, prolonged recovery anaesthesia is achievable with MS-222 dilutions in salamander. Reflectance SpO2 could prove valuable during immersion anaesthesia.


Assuntos
Anestesia , Salamandra , Animais , Aminobenzoatos , Anestesia/métodos , Mesilatos
17.
J Anat ; 219(4): 502-14, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21668895

RESUMO

Regional variation in the axial skeleton of pinnipeds (seals and walruses) and its correlation with aquatic locomotory behaviour is examined using vertebral functional profiles. The results demonstrate clear morpho-functional differences in the thoracolumbar region of modern pinnipeds (Phocidae, Otariidae, Odobenus) that can be strongly linked to swimming style. Phocid seals have a rigid thoracic region attached to a highly flexible lumbar region with long muscular lever arms providing the necessary mobility and leverage to perform pelvic oscillations. Conversely, otariid seals have extremely flexible inter-vertebral joints along the length of the column which should enhance manoeuvrability and turning performance. They also have greater muscular leverage in the anterior thoracic region to support pectoral oscillations. Odobenus (walrus) shows vertebral characteristics most similar to phocids, but with some otariid qualities, consistent with an intermediate or mixed form of aquatic locomotion, with pelvic oscillation dominating over pectoral oscillation. Comparison of the vertebral functional profiles in the fossil taxon Allodesmus kernensis with those of modern pinniped clades reveals that this extinct pinniped may also have used a combination of pectoral and pelvic oscillatory movements during swimming, but in a manner opposite to that of Odobenus, with pectoral oscillatory movements dominating. This study raises questions about the evolution and diversification of pinniped locomotory behaviours, but also provides the necessary framework to begin to examine axial mechanics and locomotory stages in other fossil pinnipedimorphs and their relatives in more detail.


Assuntos
Caniformia/fisiologia , Fósseis , Coluna Vertebral/anatomia & histologia , Natação/fisiologia , Animais , Caniformia/anatomia & histologia , Feminino , Masculino
18.
Br J Dermatol ; 164(6): 1311-5, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21332456

RESUMO

BACKGROUND: Healthcare-associated infection is an important worldwide problem that could be reduced by better hand hygiene practice. However, an increasing number of healthcare workers are experiencing irritant contact dermatitis of the hands as a result of repeated hand washing. This may lead to a reduced level of compliance with regard to hand hygiene. OBJECTIVES: To assess whether a measure of acute irritation by hand soaps could predict the effects of repeated usage over a 2-week period. METHODS: In a double-blind, randomized comparison study, the comparative irritation potential of four different hand soaps was assessed over a 24-h treatment period. The effect of repeated hand washing with the hand soap products over a 2-week period in healthy adult volunteers on skin barrier function was then determined by assessment of transepidermal water loss (TEWL), epidermal hydration and a visual assessment using the Hand Eczema Severity Index (HECSI) at days 0, 7 and 14. RESULTS: A total of 121 subjects from the 123 recruited completed phase 1 of the study. All four products were seen to be significantly different from each other in terms of the irritant reaction observed and all products resulted in a significantly higher irritation compared with the no-treatment control. Seventy-nine of the initial 121 subjects were then enrolled into the repeated usage study. A statistically significant worsening of the clinical condition of the skin as measured by HECSI was seen from baseline to day 14 in those subjects repeatedly washing their hands with two of the four soap products (products C and D) with P-values of 0·02 and 0·01, respectively. Subclinical assessment of the skin barrier function by measuring epidermal hydration was significantly increased from baseline to day 7 after repeated hand washing with products A, B and D but overall no significant change was seen in all four products tested by day 14. A statistically significant increase in TEWL at day 14 was seen for product A (P = 0·02) indicating a worsening of skin barrier function. This effect was also seen initially for product D at day 7 although this was then lost at day 14. Further regression analysis was then performed to see if the acute irritant test data for each product correlated with the skin barrier data from the repeated usage component of the study. This showed that the results of acute irritant testing of the individual products did not predict the results of chronic use of hand soaps. CONCLUSIONS: The results from phase 2 of our study confirm the work of previous studies that show that regular exposure to irritants in daily life leads to stratum corneum damage and impairment of the skin barrier. Although significant differences were seen between the products in phase 1 of the study, regression analysis showed that the results of patch testing of the individual products did not predict the results of chronic use of hand soaps. When designing a study to assess the effects of cumulative use of a product on the skin, the study should mirror the use conditions of the product as closely as possible.


Assuntos
Dermatite Irritante/diagnóstico , Toxidermias/diagnóstico , Dermatoses da Mão/induzido quimicamente , Desinfecção das Mãos , Sabões/efeitos adversos , Adolescente , Adulto , Idoso , Dermatite Irritante/etiologia , Método Duplo-Cego , Toxidermias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro , Prognóstico , Absorção Cutânea/efeitos dos fármacos , Perda Insensível de Água/efeitos dos fármacos , Adulto Jovem
19.
J Fish Biol ; 78(1): 378-85, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21235570

RESUMO

Laser photogrammetry was found to be a promising new cost-effective technique for measuring free-swimming whale sharks Rhincodon typus. Photogrammetric measurements were more precise than visual size estimates by experienced researchers, with results from the two methods differing by 9· 8 ± 1· 1% (mean ±s.e.). A new metric of total length and the length between the fifth gill and first dorsal fin (r² = 0· 93) is proposed to facilitate easy, accurate length measurements of whale sharks in the field.


Assuntos
Tamanho Corporal , Tubarões/crescimento & desenvolvimento , Animais , Lasers , Fotogrametria , Tubarões/anatomia & histologia
20.
Integr Org Biol ; 3(1): obab026, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34661062

RESUMO

Deciphering the biological function of rare or extinct species is key to understanding evolutionary patterns across the tree of life. While soft tissues are vital determinants of joint function, they are rarely available for study. Therefore, extracting functional signals from skeletons, which are more widely available via museum collections, has become a priority for the field of comparative biomechanics. While most work has focused on the limb skeleton, the axial skeleton plays a critical role in body support, respiration, and locomotion, and is therefore of central importance for understanding broad-scale functional evolution. Here, we describe and experimentally validate AutoBend, an automated approach to estimating intervertebral joint function from bony vertebral columns. AutoBend calculates osteological range of motion (oROM) by automatically manipulating digitally articulated vertebrae while incorporating multiple constraints on motion, including both bony intersection and the role of soft tissues by restricting excessive strain in both centrum and zygapophyseal articulations. Using AutoBend and biomechanical data from cadaveric experiments on cats and tegus, we validate important modeling parameters required for oROM estimation, including the degree of zygapophyseal disarticulation, and the location of the center of rotation. Based on our validation, we apply a model with the center of rotation located within the vertebral disk, no joint translation, around 50% strain permitted in both zygapophyses and disks, and a small amount of vertebral intersection permitted. Our approach successfully reconstructs magnitudes and craniocaudal patterns of motion obtained from ex vivo experiments, supporting its potential utility. It also performs better than more typical methods that rely solely on bony intersection, emphasizing the importance of accounting for soft tissues. We estimated the sensitivity of the analyses to vertebral model construction by varying joint spacing, degree of overlap, and the impact of landmark placement. The effect of these factors was small relative to biological variation craniocaudally and between bending directions. We also present a new approach for estimating joint stiffness directly from oROM and morphometric measurements that can successfully reconstruct the craniocaudal patterns, but not magnitudes, derived from experimental data. Together, this work represents a significant step forward for understanding vertebral function in difficult-to-study (e.g., rare or extinct) species, paving the way for a broader understanding of patterns of functional evolution in the axial skeleton.


Resumo [Portuguese] Decifrar a função biológica de espécies raras ou extintas é fundamental para se compreender os padrões evolutivos na árvore da vida. Embora os tecidos moles sejam determinantes vitais das funções articulares, estes raramente estão disponíveis para estudo. Portanto, extrair dados funcionais provenientes de esqueletos, que são mais amplamente disponíveis por meio de coleções de museus, tornou-se uma prioridade para o campo da biomecânica comparada. Embora a maioria dos trabalhos biomecânicos tenham focado no esqueleto apendicular, o esqueleto axial também desempenha um papel crítico para o suporte corporal, respiração e locomoção e, portanto, é de importância central para a compreensão da evolução funcional em escalas amplas. Nesse trabalho, nós descrevemos e validamos experimentalmente o AutoBend, uma abordagem automatizada para estimar a função da articulação intervertebral de colunas vertebrais ósseas. O AutoBend calcula a amplitude do movimento osteológico (AMO) manipulando automaticamente as vértebras reconstruídas digitalmente e incorporando várias restrições de movimento, incluindo restrições das interseções ósseas e o papel de restrição dos tecidos moles na tensão excessiva sobre as articulações dos centros vertebrais e zigapofisárias. Usando AutoBend e dados biomecânicos de experimentos cadavéricos em gatos e lagartos tegus, validamos parâmetros de modelagem importantes e necessários para as estimativa do AMO, incluindo o grau de desarticulação zigapofisária e a localização do centro de rotação. Com base nessa validação, aplicamos um modelo com o centro de rotação localizado dentro do disco vertebral, sem translação articular, com cerca de 50% de tensão permitida nas zigapófises e discos vertebrais, além de uma pequena quantidade de intersecção vertebral permitida. Nossa abordagem reconstrói com sucesso magnitudes e padrões de movimento craniocaudais obtidos a partir de experimentos ex vivo, corroborando a sua potencial utilidade. Esse modelo também tem um desempenho melhor do que os métodos mais típicos que dependem apenas das interseções ósseas, enfatizando a importância de se levar em conta o papel dos tecidos moles. Estimamos a sensibilidade das análises à reconstrução do modelo vertebral, variando o espaçamento entre articulações, o grau de sobreposição e o impacto da localização dos pontos de referência. O efeito desses fatores foi pequeno em relação à variação biológica craniocaudal e entre as direções de flexão. Apresentamos aqui também uma nova abordagem para se estimar a rigidez articular diretamente à partir do AMO e medidas morfométricas que podem reconstruir com sucesso os padrões craniocaudais (embora não as magnitudes) derivados de dados experimentais. Este trabalho representa um passo significativo para a melhor compreensão da função vertebral em espécies difíceis de estudar (por exemplo, raras ou extintas), abrindo caminho para uma compreensão mais ampla dos padrões de evolução funcional no esqueleto axial.


Resumen [Spanish] Descifrar la función biológica de especies raras o extintas es fundamental para comprender los patrones evolutivos del árbol de la vida. Aunque los tejidos blandos son determinantes vitales de la función articular, raramente están disponibles para su estudio. Por lo tanto, la extracción de datos funcionales de esqueletos, que están más comumente disponibles a través de colecciones de museos, se ha convertido en una prioridad para el campo de la biomecánica comparada. Aunque la mayor parte del trabajo biomecánico se ha centrado en el esqueleto apendicular, el esqueleto axial también desempeña un papel fundamental para el soporte del cuerpo, la respiración y la locomoción y, por lo tanto, es de vital importancia para comprender la evolución funcional a gran escala. En este trabajo, describimos y validamos experimentalmente AutoBend, una herramienta automatizada para estimar la función de la articulación intervertebral en las columnas vertebrales óseas. AutoBend calcula el rango de movimiento osteológico (RMOo) manipulando automáticamente las vértebras reconstruidas digitalmente e incorporando varias restricciones de movimiento, incluidas las restricciones de intersección ósea y el papel de la restricción de tejidos blandos en la tensión excesiva sobre las articulaciones cigapofisarias y centros vertebrales. Utilizando AutoBend y datos biomecánicos de experimentos cadavéricos en gatos y lagartos tegus, validamos importantes parámetros de modelado necesarios para estimar el RMOo, incluido el grado de desarticulación cigapofisaria y la ubicación del centro de rotación. Con base en esta validación, aplicamos un modelo con el centro de rotación ubicado dentro del disco vertebral, sin traslación articular, con 50% de tensión permisible en la cigapófisis y los discos vertebrales, además de una pequeña cantidad de intersección vertebral permitida. Nuestra herramienta reconstruye con éxito magnitudes craneocaudales y patrones de movimiento obtenidos de experimentos ex vivo, corroborando su potencial utilidad. Este modelo también funciona mejor que los métodos más típicos que se basan solo en las intersecciones óseas, enfatizando la importancia de tener en cuenta el papel de los tejidos blandos. Estimamos la sensibilidad de los análisis a la reconstrucción del modelo vertebral, variando el espaciamiento entre articulaciones, el grado de superposición y el impacto de la ubicación de los puntos de referencia. El efecto de estos factores fue pequeño en relación a la variación biológica craneocaudal y entre las direcciones de flexión. También presentamos aquí un nuevo enfoque para estimar la rigidez articular directamente de la RMOo y mediciones morfométricas que pueden reconstruir con éxito los patrones craneocaudales (aunque no las magnitudes) derivados de datos experimentales. Este trabajo representa un paso significativo hacia una mejor comprensión de la función vertebral en especies difíciles de estudiar (por ejemplo, raras o extintas), allanando el camino para una comprensión más amplia de los patrones de evolución funcional en el esqueleto axial.

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