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1.
Resusc Plus ; 13: 100357, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36691447

RESUMO

Objective: Out-of-hospital blood transfusion (OHBT) is becoming increasingly common across the prehospital environment, yet there is significant variability in OHBT practices. The Canadian Prehospital and Transport Transfusion (CAN-PATT) network was established to collaborate, standardize, and evaluate the effectiveness of out-of-hospital blood transfusion (OHBT) across Canada. The objectives of this study are to describe the setting and organizational characteristics of CAN-PATT member organizations and to provide a cross-sectional examination of the current OHBT practices of CAN-PATT organizations. Methods: This was a cross-sectional examination of all six critical care transport organizations that are involved in CAN-PATT network. Surveys were sent to identified leads from each organization. The survey focused on three main areas of interest: 1) critical care transport organizational service and coverage, 2) provider, and crew configurations, and 3) OHBT transfusion practices. Results: All six surveys were completed and returned. There are a total of 30 critical care transport bases (19 rotor-wing, 20 fixed-wing and 6 land) across Canada and 11 bases have a blood-on-board program. Crew configurations very between organizations as either dual paramedic or paramedic/nurse teams. Median transport times range from 30 to 46 minutes for rotor-wing assets and 64 to 90 minutes for fixed-wing assets. Half of the CAN-PATT organizations started their out-of-hospital blood transfusion programs within the last three years. Most organizations carry at least two units of O-negative, K-negative red blood cells and some organizations also carry group A thawed plasma, fibrinogen concentrate and/or prothrombin complex concentrate. All organizations advocate for early administration of tranexamic acid for injured patients suspected of bleeding. All organizations return un-transfused blood components to their local transfusion medicine laboratory within a predefined timeframe to reduce wastage. Conclusions: Variations in OHBT practices were identified and we have suggested considerations for standardization of transfusion practices and patient care as it relates to OHBT. This standardization will also enable a robust means of data collection to study and optimize outcomes of patients receiving OHBT. A fulsome description of the participating organizations within CAN-PATT should enhance interpretation of future OHBT studies that will be conducted by this network.

2.
Orthop Traumatol Surg Res ; 106(3): 563-568, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31959362

RESUMO

BACKGROUND: Anterior hip pain after total hip replacement (THR) can be caused by iliopsoas impingement (IPI). Validation of CT measured cup version is well published; however quantification of the anterior cup prominence has not been validated. Therefore, we did an in vitro study aiming to: (1) assess the accuracy of the current method of measuring the prominence of the acetabular component using a dry bone model; (2) develop a CT protocol based on bony anatomical landmarks that improves the accuracy of these measurements. HYPOTHESIS: We hypothesise that utilising reproducible anatomical landmarks on the acetabulum will improve the accuracy of measurement of anterior prominence at the psoas valley. METHODS: A dry bone pelvic model was implanted with bilateral acetabular cups. The cup was manipulated into ten different combinations of inclination and version, and anterior prominence directly measured in relation to the acetabular rim. A CT scan was performed for each position. Anterior prominence was then measured by two radiologists, first using standard methods (axial slice at level of centre of femoral head) and then again using a novel protocol (based on the position of the psoas valley in relation to the inferior medial acetabular notch). RESULTS: Mean errors between direct measurement of anterior prominence and radiologist reported measurements using standard protocol were 6.94mm±5.24 (SD) (95%Confidence Interval: 3.25-4.27) and 5.14mm±3.07 (95%CI: 1.9-2.5) with a tendency towards overestimation of prominence. Using an anatomical landmark based protocol; mean error was reduced to 3.0mm±1.9 (95%CI: 1.16-1.53) and 4.3mm±4.3 (95%CI: 2.67-351) on the first attempt, and to 1.7mm±1.9 (95%CI: 1.15-1.52) and 2.1mm±1.4 (95%CI: 0.87-1.15) on the second attempt. Concordance correlation improved from 0.43 (95% CI: 0.19-0.68) and 0.59 (95% CI: 0.44-0.79) using the standard protocol, to 0.88 (95%CI: 0.61-0.91) and 0.9 (95%CI: 0.56-0.92) using the novel protocol. CONCLUSIONS: There is a difference in mean error and reliability between radiologically measured values for anterior prominence and values measured directly with present methods. The use of our novel protocol based on bony acetabular landmarks, significantly improves the accuracy of measurement. This protocol may improve reproducibility and the accuracy of this measurement and aid in the decision between tenotomy or revision of the acetabular component. LEVEL OF EVIDENCE: III, in vitro study comparing diagnostic tools.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Humanos , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
3.
Sci Rep ; 9(1): 8709, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31213621

RESUMO

Low-salinity submarine groundwater contained within continental shelves is a global phenomenon. Mechanisms for emplacing offshore groundwater include glacial processes that drove water into exposed continental shelves during sea-level low stands and active connections to onshore hydrologic systems. While low-salinity groundwater is thought to be abundant, its distribution and volume worldwide is poorly understood due to the limited number of observations. Here we image laterally continuous aquifers extending 90 km offshore New Jersey and Martha's Vineyard, Massachusetts, on the U.S. Atlantic margin using new shallow water electromagnetic geophysical methods. Our data provide more continuous constraints on offshore groundwater than previous models and present evidence for a connection between the modern onshore hydrologic system and offshore aquifers. We identify clinoforms as a previously unknown structural control on the lateral extent of low-salinity groundwater and potentially a control on where low-salinity water rises into the seafloor. Our data suggest a continuous submarine aquifer system spans at least 350 km of the U.S. Atlantic coast and contains about 2800 km3 of low-salinity groundwater. Our findings can be used to improve models of past glacial, eustatic, tectonic, and geomorphic processes on continental shelves and provide insight into shelf geochemistry, biogeochemical cycles, and the deep biosphere.

4.
Nature ; 535(7613): 538-41, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-27383792

RESUMO

Convective flow in the mantle and the motions of tectonic plates produce deformation of Earth's interior, and the rock fabric produced by this deformation can be discerned using the anisotropy of the seismic wave speed. This deformation is commonly inferred close to lithospheric boundaries beneath the ocean in the uppermost mantle, including near seafloor-spreading centres as new plates are formed via corner flow, and within a weak asthenosphere that lubricates large-scale plate-driven flow and accommodates smaller scale convection. Seismic models of oceanic upper mantle differ as to the relative importance of these deformation processes: seafloor spreading fabric is very strong just beneath the crust-mantle boundary (the Mohorovicic discontinuity, or Moho) at relatively local scales, but at the global and ocean-basin scales, oceanic lithosphere typically appears weakly anisotropic when compared to the asthenosphere. Here we use Rayleigh waves, recorded across an ocean-bottom seismograph array in the central Pacific Ocean (the NoMelt Experiment), to provide unique localized constraints on seismic anisotropy within the oceanic lithosphere-asthenosphere system in the middle of a plate. We find that azimuthal anisotropy is strongest within the high-seismic-velocity lid, with the fast direction coincident with seafloor spreading. A minimum in the magnitude of azimuthal anisotropy occurs within the middle of the seismic low-velocity zone, and then increases with depth below the weakest portion of the asthenosphere. At no depth does the fast direction correlate with the apparent plate motion. Our results suggest that the highest strain deformation in the shallow oceanic mantle occurs during corner flow at the ridge axis, and via pressure-driven or buoyancy-driven flow within the asthenosphere. Shear associated with motion of the plate over the underlying asthenosphere, if present, is weak compared to these other processes.

5.
Cogn Neurodyn ; 9(5): 535-47, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26379803

RESUMO

Microarray gene expression data can provide insights into biological processes at a system-wide level and is commonly used for reverse engineering gene regulatory networks (GRN). Due to the amalgamation of noise from different sources, microarray expression profiles become inherently noisy leading to significant impact on the GRN reconstruction process. Microarray replicates (both biological and technical), generated to increase the reliability of data obtained under noisy conditions, have limited influence in enhancing the accuracy of reconstruction . Therefore, instead of the conventional GRN modeling approaches which are deterministic, stochastic techniques are becoming increasingly necessary for inferring GRN from noisy microarray data. In this paper, we propose a new stochastic GRN model by investigating incorporation of various standard noise measurements in the deterministic S-system model. Experimental evaluations performed for varying sizes of synthetic network, representing different stochastic processes, demonstrate the effect of noise on the accuracy of genetic network modeling and the significance of stochastic modeling for GRN reconstruction . The proposed stochastic model is subsequently applied to infer the regulations among genes in two real life networks: (1) the well-studied IRMA network, a real-life in-vivo synthetic network constructed within the Saccharomyces cerevisiae yeast, and (2) the SOS DNA repair network in Escherichia coli.

6.
New Phytol ; 206(4): 1314-27, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25676073

RESUMO

Fasciclin-like arabinogalactan protein (FLA) families have been identified and characterised in key plant species, with some members exhibiting functional specialization. Here we identify the FLA family of Eucalyptus grandis, and investigate the roles of three single-FAS domain FLAs, with particular focus on secondary cell-wall formation and wood properties. We use various in-silico approaches to identify and characterise E. grandis genome FLAs, and perform phylogenetic comparisons with other species. For three key FLAs, we perform functional testing including promoter-reporter and overexpression transgenic approaches using eucalypts, poplar and tobacco. Of the 18 eucalypt FLAs identified, several were specifically and highly expressed in stems. The specificity to stem xylem vessel and fibre development was demonstrated with EniFLA1promoter:GUS studies in several species. Testing of select eucalypt FLAs resulted in altered wood development and properties, for example 35S:EgrFLA2 led to a 3 degree reduction in cellulose microfibril angle in eucalypt xylem fibres, and 35S:EgrFLA3 to a reduction in tobacco stem flexural strength. These results indicate that the eucalypt FLA family contains diverse members, and particular members with single FAS domains that are functionally specialized for secondary cell wall growth and properties.


Assuntos
Eucalyptus/genética , Eucalyptus/fisiologia , Mucoproteínas/genética , Família Multigênica , Proteínas de Plantas/genética , Madeira/fisiologia , Fenômenos Biomecânicos , Parede Celular/metabolismo , Celulose/metabolismo , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Glucose/metabolismo , Glucuronidase/metabolismo , Dados de Sequência Molecular , Mucoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/metabolismo , Plantas Geneticamente Modificadas , Populus/genética , Regiões Promotoras Genéticas/genética , Nicotiana/genética , Transformação Genética , Xilema/genética , Xilose/metabolismo
7.
Nature ; 511(7509): 338-40, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25030172

RESUMO

Convergent margin volcanism originates with partial melting, primarily of the upper mantle, into which the subducting slab descends. Melting of this material can occur in one of two ways. The flow induced in the mantle by the slab can result in upwelling and melting through adiabatic decompression. Alternatively, fluids released from the descending slab through dehydration reactions can migrate into the hot mantle wedge, inducing melting by lowering the solidus temperature. The two mechanisms are not mutually exclusive. In either case, the buoyant melts make their way towards the surface to reside in the crust or to be extruded as lava. Here we use magnetotelluric data collected across the central state of Washington, USA, to image the complete pathway for the fluid-melt phase. By incorporating constraints from a collocated seismic study into the magnetotelluric inversion process, we obtain superior constraints on the fluids and melt in a subduction setting. Specifically, we are able to identify and connect fluid release at or near the top of the slab, migration of fluids into the overlying mantle wedge, melting in the wedge, and transport of the melt/fluid phase to a reservoir in the crust beneath Mt Rainier.

8.
Nature ; 509(7498): 40-1, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24784212
9.
Opt Express ; 21(1): 370-81, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23388930

RESUMO

Edge mis-figure is regarded as one of the most difficult technical issues for manufacturing the segments of extremely large telescopes, which can dominate key aspects of performance. A novel edge-control technique has been developed, based on 'Precessions' polishing technique and for which accurate and stable edge tool influence functions (TIFs) are crucial. In the first paper in this series [D. Walker Opt. Express 20, 19787-19798 (2012)], multiple parameters were experimentally optimized using an extended set of experiments. The first purpose of this new work is to 'short circuit' this procedure through modeling. This also gives the prospect of optimizing local (as distinct from global) polishing for edge mis-figure, now under separate development. This paper presents a model that can predict edge TIFs based on surface-speed profiles and pressure distributions over the polishing spot at the edge of the part, the latter calculated by finite element analysis and verified by direct force measurement. This paper also presents a hybrid-measurement method for edge TIFs to verify the simulation results. Experimental and simulation results show good agreement.

10.
Funct Plant Biol ; 40(7): 662-676, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32481139

RESUMO

The natural trait variation in Arabidopsis thaliana (L.) Heynh. accessions is an important resource for understanding many biological processes but it is underexploited for wood-related properties. Twelve A. thaliana accessions from diverse geographical locations were examined for variation in secondary growth, biomechanical properties, cell wall glycan content, cellulose microfibril angle (MFA) and flowering time. The effect of daylength was also examined. Secondary growth in rosette and inflorescence stems was observed in all accessions. Organised cellulose microfibrils in inflorescence stems were found in plants grown under long and short days. A substantial range of phenotypic variation was found in biochemical and wood-related biophysical characteristics, particularly for tensile strength, tensile stiffness, MFA and some cell wall components. The four monosaccharides galactose, arabinose, rhamnose and fucose strongly correlated with each other as well as with tensile strength and MFA, consistent with mutations in arabinogalactan protein and fucosyl- and xyloglucan galactosyl-transferase genes that result in decreases in strength. Conversely, these variables showed negative correlations with lignin content. Our data support the notion that large-scale natural variation studies of wood-related biomechanical and biochemical properties of inflorescence stems will be useful for the identification of novel genes important for wood formation and quality, and therefore biomaterial and renewable biofuel production.

11.
Opt Express ; 20(18): 19787-98, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037031

RESUMO

Segment-edges for extremely large telescopes are critical for observations requiring high contrast and SNR, e.g. detecting exo-planets. In parallel, industrial requirements for edge-control are emerging in several applications. This paper reports on a new approach, where edges are controlled throughout polishing of the entire surface of a part, which has been pre-machined to its final external dimensions. The method deploys compliant bonnets delivering influence functions of variable diameter, complemented by small pitch tools sized to accommodate aspheric mis-fit. We describe results on witness hexagons in preparation for full size prototype segments for the European Extremely Large Telescope, and comment on wider applications of the technology.


Assuntos
Astronomia/instrumentação , Desenho Assistido por Computador , Lentes , Desenho de Equipamento , Análise de Falha de Equipamento
12.
Plant J ; 62(4): 689-703, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20202165

RESUMO

The ancient cell adhesion fasciclin (FAS) domain is found in bacteria, fungi, algae, insects and animals, and occurs in a large family of fasciclin-like arabinogalactan proteins (FLAs) in higher plants. Functional roles for FAS-containing proteins have been determined for insects, algae and vertebrates; however, the biological functions of the various higher-plant FLAs are not clear. Expression of some FLAs has been correlated with the onset of secondary-wall cellulose synthesis in Arabidopsis stems, and also with wood formation in the stems and branches of trees, suggesting a biological role in plant stems. We examined whether FLAs contribute to plant stem biomechanics. Using phylogenetic, transcript abundance and promoter-GUS fusion analyses, we identified a conserved subset of single FAS domain FLAs (group A FLAs) in Eucalyptus and Arabidopsis that have specific and high transcript abundance in stems, particularly in stem cells undergoing secondary-wall deposition, and that the phylogenetic conservation appears to extend to other dicots and monocots. Gene-function analyses revealed that Arabidopsis T-DNA knockout double mutant stems had altered stem biomechanics with reduced tensile strength and a reduced tensile modulus of elasticity, as well as altered cell-wall architecture and composition, with increased cellulose microfibril angle and reduced arabinose, galactose and cellulose content. Using materials engineering concepts, we relate the effects of these FLAs on cell-wall composition with stem biomechanics. Our results suggest that a subset of single FAS domain FLAs contributes to plant stem strength by affecting cellulose deposition, and to the stem modulus of elasticity by affecting the integrity of the cell-wall matrix.


Assuntos
Arabidopsis/metabolismo , Parede Celular/metabolismo , Eucalyptus/metabolismo , Mucoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Caules de Planta/crescimento & desenvolvimento , Arabidopsis/genética , DNA Bacteriano/genética , Módulo de Elasticidade , Eucalyptus/genética , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Lignina/metabolismo , Mucoproteínas/genética , Mutagênese Insercional , Filogenia , Proteínas de Plantas/genética , Resistência à Tração
13.
Science ; 326(5956): 1089-91, 2009 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-19965424

RESUMO

When plate tectonics started on Earth has been uncertain, and its role in the assembly of early continents is not well understood. By synthesizing coincident seismic and electrical profiles, we show that subduction processes formed the Archean Slave craton in Canada. The spatial overlap between a seismic discontinuity and a conductive anomaly at approximately 100 kilometers depth, in conjunction with the occurrence of mantle xenoliths rich in secondary minerals representative of a metasomatic front, supports cratonic assembly by subduction and accretion of lithospheric fragments. Although evidence of cratonic assembly is rarely preserved, these results suggest that plate tectonics was operating as early as Paleoarchean times, approximately 3.5 billion years ago (Ga).

14.
Dis Aquat Organ ; 82(1): 61-5, 2008 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-19062754

RESUMO

Wild Atlantic salmon Salmo salar with swollen and/or bleeding vents (red vent syndrome) have been observed in rivers across England and Wales. Low numbers of salmon with this condition have previously been recorded, but reports have increased in 2006 and 2007. Affected and non-affected salmon were sampled from fish traps and their vent pathology was examined. Third stage larvae of the nematode Anisakis simplex sensu lato were observed in the tissue surrounding the vent in all affected fish. Histology of the vent showed gross lesions with an inflammatory response associated with non-encapsulated nematode worms in the connective tissue and skeletal muscle. The presence of the parasite in the unusual location of the vent areas, with associated haemorrhaging, is possibly a new emerging pathological association with the nematode A. simplex infection in Atlantic salmon. The reason for this unusual tissue tropism by larval A. simplex and the significance on already depleted salmon stocks are currently unknown.


Assuntos
Anisaquíase/veterinária , Anisakis/classificação , Doenças dos Peixes/parasitologia , Salmo salar , Animais , Animais Selvagens , Anisaquíase/epidemiologia , Anisaquíase/parasitologia , Anisakis/isolamento & purificação , Inglaterra/epidemiologia , Doenças dos Peixes/epidemiologia , Trato Gastrointestinal/parasitologia , Trato Gastrointestinal/patologia , País de Gales/epidemiologia
15.
Science ; 322(5906): 1338-40, 2008 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-19039127
16.
Cleft Palate Craniofac J ; 45(4): 353-63, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18616366

RESUMO

OBJECTIVE: To assess speech outcomes following midface advancement and to explore whether the type of advancement surgery affects speech differently in patients with craniofacial dysostosis. DESIGN: Prospective, before-after group design. SUBJECTS: Fifteen consecutive patients were included in the study. Eight underwent advancement by osteotomy and seven by distraction. All patients were seen preoperatively and at least once postoperatively. MAIN OUTCOME MEASURES: Percentage of consonants correct, nature and type of articulation errors, nasalance score, severity ratings of resonance and of velopharyngeal function using nasendoscopy and lateral videofluoroscopy, and amount of forward advancement. RESULTS: No statistically significant differences were found between groups for pre- and postoperative changes of percentage of consonants correct (p = .755, median difference 3.0, 95% confidence interval for median difference [-14.22, 20.22]) and nasalance (p = .171, median difference = -12.00, 95% confidence interval for median differences [-30.46, 6.46]). There was no statistically significant correlation between amount of forward advancement and nasalance (r = .87, p = .799) and percentage of consonants correct (r = -.550, p = .064). Findings from lateral videofluoroscopy and nasendoscopy are described. Individual changes of speech outcomes are reported. CONCLUSIONS: In view of the small sample size, results need to be interpreted with caution. However, the study adds to current limited knowledge with this clinical group. Further research with bigger sample sizes and randomization of patients into the different surgical groups is warranted.


Assuntos
Transtornos da Articulação/etiologia , Disostose Craniofacial/cirurgia , Maxila/cirurgia , Osteogênese por Distração , Osteotomia de Le Fort , Insuficiência Velofaríngea/etiologia , Distúrbios da Voz/etiologia , Adolescente , Transtornos da Articulação/diagnóstico , Criança , Disostose Craniofacial/complicações , Feminino , Humanos , Masculino , Estudos Prospectivos , Acústica da Fala , Insuficiência Velofaríngea/diagnóstico , Distúrbios da Voz/diagnóstico
17.
Nature ; 437(7056): 249-52, 2005 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-16148932

RESUMO

Magnetotelluric and seismic data, collected during the MELT experiment at the southern East Pacific Rise, constrain the distribution of melt beneath this mid-ocean-ridge spreading centre and also the evolution of the oceanic lithosphere during its early cooling history. Here we focus on structures imaged at distances approximately 100 to 350 km east of the ridge crest, corresponding to seafloor ages of approximately 1.3 to 4.5 million years (Myr), where the seismic and electrical conductivity structure is nearly constant and independent of age. Beginning at a depth of about 60 km, we image a large increase in electrical conductivity and a change from isotropic to transversely anisotropic electrical structure, with higher conductivity in the direction of fast propagation for seismic waves. Conductive cooling models predict structure that increases in depth with age, extending to about 30 km at 4.5 Myr ago. We infer, however, that the structure of young oceanic plates is instead controlled by a decrease in water content above a depth of 60 km induced by the melting process beneath the spreading centre.

18.
Nature ; 429(6990): 356-7, 2004 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-15164046
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