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1.
Proc Natl Acad Sci U S A ; 117(31): 18744-18753, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32680963

RESUMO

Morphological profiling is a method to classify target pathways of antibacterials based on how bacteria respond to treatment through changes to cellular shape and spatial organization. Here we utilized the cell-to-cell variation in morphological features of Mycobacterium tuberculosis bacilli to develop a rapid profiling platform called Morphological Evaluation and Understanding of Stress (MorphEUS). MorphEUS classified 94% of tested drugs correctly into broad categories according to modes of action previously identified in the literature. In the other 6%, MorphEUS pointed to key off-target activities. We observed cell wall damage induced by bedaquiline and moxifloxacin through secondary effects downstream from their main target pathways. We implemented MorphEUS to correctly classify three compounds in a blinded study and identified an off-target effect for one compound that was not readily apparent in previous studies. We anticipate that the ability of MorphEUS to rapidly identify pathways of drug action and the proximal cause of cellular damage in tubercle bacilli will make it applicable to other pathogens and cell types where morphological responses are subtle and heterogeneous.


Assuntos
Antituberculosos/farmacologia , Descoberta de Drogas/métodos , Mycobacterium tuberculosis , Software , Parede Celular/efeitos dos fármacos , Diarilquinolinas , Ensaios de Triagem em Larga Escala , Mycobacterium tuberculosis/citologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/metabolismo , Transcriptoma/efeitos dos fármacos
2.
J Oral Maxillofac Surg ; 80(4): 651-661, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863645

RESUMO

PURPOSE: The purpose of this systematic review and meta-analysis was to estimate and compare rates of unplanned reoperation and complications after undergoing either fronto-orbital advancement (anterior cranial vault expansion) or posterior cranial vault expansion as an early surgery in the management of syndromic craniosynostosis. MATERIALS AND METHODS: A literature search was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant articles were identified in 2 electronic databases (PubMed and EMBASE) from the time of electronic publication to November 2020. Quality assessment and risk of bias were appraised using the Grading of Recommendations Assessment, Development and Evaluation system. A meta-analysis was performed comparing rates of reoperation and complications between participants who underwent anterior or posterior cranial vault expansion as an early surgery. RESULTS: Of 1,373 screened records, 7 met inclusion criteria. Six were included in the meta-analysis. The studies that met inclusion criteria reported on 103 patients treated with anterior techniques and 72 patients treated with a posterior approach. Anterior cranial vault expansion was associated with significantly higher rates of reoperation (Peto odds ratio = 2.83; 95% confidence interval = 1.19, 6.74, P = .02) and complications (Peto odds ratio = 2.61; 95% confidence interval = 1.12, 6.12, P = .03) than posterior cranial vault expansion. CONCLUSIONS: Both anterior and posterior approaches are suitable options in the treatment of syndromic craniosynostosis depending on patient-specific factors. Anterior cranial vault expansion was associated with higher rates of unplanned reoperation and complications than posterior techniques in this analysis. Because of the paucity of literature which met inclusion criteria, this study was not able to assess critical outcome variables such as distance distracted/volumetric expansion, estimated blood loss, and cost. Larger studies evaluating both techniques under multiple institutions with long-term follow-up are indicated.


Assuntos
Craniossinostoses , Osteogênese por Distração , Craniossinostoses/cirurgia , Humanos , Lactente , Morbidade , Osteogênese por Distração/métodos , Reoperação , Crânio/cirurgia
3.
Sensors (Basel) ; 21(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34203102

RESUMO

Research on fatty acids (FA) is important because their intake is related to human health. NIRS can be a useful tool to estimate the FA of beef but due to the high moisture and the high absorbance of water makes it difficult to calibrate the analyses. This work evaluated near-infrared reflectance spectroscopy as a tool to assess the total fatty acid composition and the phospholipid fraction of fatty acids of beef using freeze-dried meat. An average of 22 unrelated pure breed young bulls from 15 European breeds were reared on a common concentrate-based diet. A total of 332 longissimus thoracis steaks were analysed for fatty acid composition and a freeze-dried sample was subjected to near-infrared spectral analysis. 220 samples (67%) were used as a calibration set with the remaining 110 (33%) being used for validation of the models obtained. There was a large variation in the total FA concentration across the animals giving a good data set for the analysis and whilst the coefficient of variation was nearly 68% for the monounsaturated FA it was only 27% for the polyunsaturated fatty acids (PUFA). PLS method was used to develop the prediction models. The models for the phospholipid fraction had a low R2p and high standard error, while models for neutral lipid had the best performance, in general. It was not possible to obtain a good prediction of many individual PUFA concentrations being present at low concentrations and less variable than other FA. The best models were developed for Total FA, saturated FA, 9c18:1 and 16:1 with R2p greater than 0.76. This study indicates that NIRS is a feasible and useful tool for screening purposes and it has the potential to predict most of the FA of freeze-dried beef.


Assuntos
Ácidos Graxos , Carne , Animais , Calibragem , Bovinos , Humanos , Masculino , Carne/análise , Fosfolipídeos , Espectroscopia de Luz Próxima ao Infravermelho
4.
J Gen Intern Med ; 33(6): 877-885, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29374360

RESUMO

BACKGROUND: Genomics will play an increasingly prominent role in clinical medicine. OBJECTIVE: To describe how primary care physicians (PCPs) discuss and make clinical recommendations about genome sequencing results. DESIGN: Qualitative analysis. PARTICIPANTS: PCPs and their generally healthy patients undergoing genome sequencing. APPROACH: Patients received clinical genome reports that included four categories of results: monogenic disease risk variants (if present), carrier status, five pharmacogenetics results, and polygenic risk estimates for eight cardiometabolic traits. Patients' office visits with their PCPs were audio-recorded, and summative content analysis was used to describe how PCPs discussed genomic results. KEY RESULTS: For each genomic result discussed in 48 PCP-patient visits, we identified a "take-home" message (recommendation), categorized as continuing current management, further treatment, further evaluation, behavior change, remembering for future care, or sharing with family members. We analyzed how PCPs came to each recommendation by identifying 1) how they described the risk or importance of the given result and 2) the rationale they gave for translating that risk into a specific recommendation. Quantitative analysis showed that continuing current management was the most commonly coded recommendation across results overall (492/749, 66%) and for each individual result type except monogenic disease risk results. Pharmacogenetics was the most common result type to prompt a recommendation to remember for future care (94/119, 79%); carrier status was the most common type prompting a recommendation to share with family members (45/54, 83%); and polygenic results were the most common type prompting a behavior change recommendation (55/58, 95%). One-fifth of recommendation codes associated with monogenic results were for further evaluation (6/24, 25%). Rationales for these recommendations included patient context, family context, and scientific/clinical limitations of sequencing. CONCLUSIONS: PCPs distinguish substantive differences among categories of genome sequencing results and use clinical judgment to justify continuing current management in generally healthy patients with genomic results.


Assuntos
Atitude do Pessoal de Saúde , Tomada de Decisão Clínica , Testes Genéticos/normas , Relações Médico-Paciente , Médicos de Atenção Primária/normas , Atenção Primária à Saúde/normas , Adulto , Mapeamento Cromossômico/métodos , Mapeamento Cromossômico/normas , Tomada de Decisão Clínica/métodos , Feminino , Testes Genéticos/métodos , Humanos , Masculino , Médicos de Atenção Primária/psicologia , Projetos Piloto , Atenção Primária à Saúde/métodos , Fatores de Risco
5.
Radiographics ; 38(1): 75-89, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29320323

RESUMO

Imaging of the gallbladder has a key role in the examination of patients with abdominal pain-especially pain localized to the right upper quadrant. Pathologic conditions that affect the gallbladder include cholelithiasis and associated complications such as acute and chronic cholecystitis, choledocholithiasis, gallstone pancreatitis, and cancer. Modalities used to image the gallbladder include ultrasonography (US), computed tomography (CT), magnetic resonance (MR) imaging, and nuclear scintigraphy. US is the primary imaging modality used to evaluate entities suspected of being gallbladder disease, as it is both sensitive and specific for demonstrating gallstones, biliary duct dilatation, and inflammatory features. However, CT is often the first imaging examination performed in patients who present to the emergency department with acute abdominal pain. Because the CT appearance of gallstones is variable, depending on the composition of the stone, pattern of calcification, and presence of gas, gallstones and other gallbladder conditions can be difficult to detect at conventional multidetector CT, with which data are acquired by using a single x-ray energy spectrum. Dual-energy CT, with which one takes advantage of the material-dependent x-ray absorption behavior of concurrently acquired high- and low-kilovolt-peak data, can add value by increasing the conspicuity of noncalcified gallstones and improving the detection of acute cholecystitis and gallbladder malignancy. In addition, MR cholangiopancreatography can be helpful for assessing choledocholithiasis and complicated biliary duct disease. ©RSNA, 2018.


Assuntos
Doenças da Vesícula Biliar/diagnóstico por imagem , Imagem Multimodal , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador , Tomografia Computadorizada por Raios X
6.
Genet Sel Evol ; 48: 19, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26960806

RESUMO

BACKGROUND: Bovine tuberculosis (bTB) infection in cattle is a significant economic concern in many countries, with annual costs to the UK and Irish governments of approximately €190 million and €63 million, respectively, for bTB control. The existence of host additive and non-additive genetic components to bTB susceptibility has been established. METHODS: Two approaches i.e. single-SNP (single nucleotide polymorphism) regression and a Bayesian method were applied to genome-wide association studies (GWAS) using high-density SNP genotypes (n = 597,144 SNPs) from 841 dairy artificial insemination (AI) sires. Deregressed estimated breeding values for bTB susceptibility were used as the quantitative dependent variable. Network analysis was performed using the quantitative trait loci (QTL) that were identified as significant in the single-SNP regression and Bayesian analyses separately. In addition, an identity-by-descent analysis was performed on a subset of the most prolific sires in the dataset that showed contrasting prevalences of bTB infection in daughters. RESULTS: A significant QTL region was identified on BTA23 (P value >1 × 10(-5), Bayes factor >10) across all analyses. Sires with the minor allele (minor allele frequency = 0.136) for this QTL on BTA23 had estimated breeding values that conferred a greater susceptibility to bTB infection than those that were homozygous for the major allele. Imputation of the regions that flank this QTL on BTA23 to full sequence indicated that the most significant associations were located within introns of the FKBP5 gene. CONCLUSIONS: A genomic region on BTA23 that is strongly associated with host susceptibility to bTB infection was identified. This region contained FKBP5, a gene involved in the TNFα/NFκ-B signalling pathway, which is a major biological pathway associated with immune response. Although there is no study that validates this region in the literature, our approach represents one of the most powerful studies for the analysis of bTB susceptibility to date.


Assuntos
Cromossomos de Mamíferos , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/veterinária , Locos de Características Quantitativas , Tuberculose Bovina/genética , Alelos , Animais , Teorema de Bayes , Cruzamento , Bovinos , Indústria de Laticínios , Feminino , Genótipo , Irlanda , Masculino , Mycobacterium bovis/isolamento & purificação , Polimorfismo de Nucleotídeo Único , Tuberculose Bovina/microbiologia , Reino Unido
7.
Genet Sel Evol ; 46: 77, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25407624

RESUMO

BACKGROUND: Infection of livestock with bovine tuberculosis (bTB; Mycobacterium bovis) is of major economical concern in many countries; approximately 15 000 to 20 000 cattle are infected per year in Ireland. The objective of this study was to quantify the genetic variation for bTB susceptibility in Irish dairy and beef cattle. METHODS: A total of 105 914 cow, 56 904 heifer and 21 872 steer single intra-dermal comparative tuberculin test records (i.e., binary trait) collected from the years 2001 to 2010 from dairy and beef herds were included in the analysis. Only animal level data pertaining to periods of herd bTB infection were retained. Variance components for bTB were estimated using animal linear and threshold mixed models and co-variances were estimated using sire linear mixed models. RESULTS: Using a linear model, the heritability for susceptibility to bTB in the entire dataset was 0.11 and ranged from 0.08 (heifers in dairy herds) to 0.19 (heifers in beef herds) among the sub-populations investigated. Differences in susceptibility to bTB between breeds were clearly evident. Estimates of genetic correlations for bTB susceptibility between animal types (i.e., cows, heifers, steers) were all positive (0.10 to 0.64), yet different from one. Furthermore, genetic correlations for bTB susceptibility between environments that differed in herd prevalence of bTB ranged from 0.06 to 0.86 and were all different from one. CONCLUSIONS: Genetic trends for bTB susceptibility observed in this study suggest a slight increase in genetic susceptibility to bTB in recent years. Since bTB is of economic importance and because all animals are routinely tested at least once annually in Ireland and some other countries, the presence of genetic variation for bTB susceptibility suggests that bTB susceptibility should be included in a national breeding program to halt possible deterioration in genetic susceptibility to bTB infection.


Assuntos
Predisposição Genética para Doença , Tuberculose Bovina/genética , Animais , Bovinos , Feminino , Irlanda , Masculino , Modelos Estatísticos , Teste Tuberculínico
8.
J Spec Oper Med ; 24(2): 67-71, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38865655

RESUMO

BACKGROUND: Medical training and evaluation are important for mission readiness in the pararescue career field. Because evaluation methods are not standardized, evaluation methods must align with training objectives. We propose an alternative evaluation method and discuss relevant factors when designing military medical evaluation metrics. METHODS: We compared two evaluation methods, the traditional checklist (TC) method used in the pararescue apprentice course and an alternative weighted checklist (AWC) method like that used at the U.S. Army static line jumpmaster course. The AWC allows up to two minor errors, while critical task errors result in autofailure. We recorded 168 medical scenarios during two Apprentice course classes and retroactively compared the two evaluation methods. RESULTS: Despite the possibility of auto-failure with the AWC, there was no significant difference between the two evaluation methods, and both showed similar overall pass rates (TC=50% pass, AWC=48.8% pass, p=.41). The two evaluation methods yielded the same result for 147 out of 168 scenarios (87.5%). CONCLUSIONS: The AWC method strongly emphasizes critical tasks without significantly increasing failures. It may provide additional benefits by being more closely aligned with our training objectives while providing quantifiable data for a longitudinal review of student performance.


Assuntos
Lista de Checagem , Medicina Militar , Militares , Humanos , Avaliação Educacional/métodos , Competência Clínica
9.
Micromachines (Basel) ; 12(6)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071701

RESUMO

Oxide dispersion-strengthened (ODS) Eurofer steel was laser welded using a short pulse duration and a designed pattern to minimise local heat accumulation. With a laser power of 2500 W and a duration of more than 3 ms, a full penetration can be obtained in a 1 mm thick plate. Material loss was observed in the fusion zone due to metal vaporisation, which can be fully compensated by the use of filler material. The solidified fusion zone consists of an elongated dual phase microstructure with a bimodal grain size distribution. Nano-oxide particles were found to be dispersed in the steel. Electron backscattered diffraction (EBSD) analysis shows that the microstructure of the heat-treated joint is recovered with substantially unaltered grain size and lower misorientations in different regions. The experimental results indicate that joints with fine grains and dispersed nano-oxide particles can be achieved via pulsed laser beam welding using filler material and post heat treatment.

10.
Materials (Basel) ; 14(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885599

RESUMO

One of the challenges for development, qualification and optimisation of arc welding processes lies in characterising the complex melt-pool behaviour which exhibits highly non-linear responses to variations of process parameters. The present work presents a computational model to describe the melt-pool behaviour in root-pass gas metal arc welding (GMAW). Three-dimensional numerical simulations have been performed using an enhanced physics-based computational model to unravel the effect of groove shape on complex unsteady heat and fluid flow in GMAW. The influence of surface deformations on the magnitude and distribution of the heat input and the forces applied to the molten material were taken into account. Utilising this model, the complex thermal and fluid flow fields in melt pools were visualised and described for different groove shapes. Additionally, experiments were performed to validate the numerical predictions and the robustness of the present computational model is demonstrated. The model can be used to explore the physical effects of governing fluid flow and melt-pool stability during gas metal arc root welding.

11.
Space Sci Rev ; 217(8): 82, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34789949

RESUMO

Geomagnetic storms are an important aspect of space weather and can result in significant impacts on space- and ground-based assets. The majority of strong storms are associated with the passage of interplanetary coronal mass ejections (ICMEs) in the near-Earth environment. In many cases, these ICMEs can be traced back unambiguously to a specific coronal mass ejection (CME) and solar activity on the frontside of the Sun. Hence, predicting the arrival of ICMEs at Earth from routine observations of CMEs and solar activity currently makes a major contribution to the forecasting of geomagnetic storms. However, it is clear that some ICMEs, which may also cause enhanced geomagnetic activity, cannot be traced back to an observed CME, or, if the CME is identified, its origin may be elusive or ambiguous in coronal images. Such CMEs have been termed "stealth CMEs". In this review, we focus on these "problem" geomagnetic storms in the sense that the solar/CME precursors are enigmatic and stealthy. We start by reviewing evidence for stealth CMEs discussed in past studies. We then identify several moderate to strong geomagnetic storms (minimum Dst < - 50  nT) in solar cycle 24 for which the related solar sources and/or CMEs are unclear and apparently stealthy. We discuss the solar and in situ circumstances of these events and identify several scenarios that may account for their elusive solar signatures. These range from observational limitations (e.g., a coronagraph near Earth may not detect an incoming CME if it is diffuse and not wide enough) to the possibility that there is a class of mass ejections from the Sun that have only weak or hard-to-observe coronal signatures. In particular, some of these sources are only clearly revealed by considering the evolution of coronal structures over longer time intervals than is usually considered. We also review a variety of numerical modelling approaches that attempt to advance our understanding of the origins and consequences of stealthy solar eruptions with geoeffective potential. Specifically, we discuss magnetofrictional modelling of the energisation of stealth CME source regions and magnetohydrodynamic modelling of the physical processes that generate stealth CME or CME-like eruptions, typically from higher altitudes in the solar corona than CMEs from active regions or extended filament channels.

12.
Meat Sci ; 153: 51-57, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30901612

RESUMO

Increasing the lipid concentration and/or inclusion of nitrate in the diet of ruminant livestock have been proposed as effective strategies to reduce the contribution of methane from the agricultural sector to greenhouse gas emissions. In this study, the effects of increased lipid or added nitrate on beef eating quality were investigated in two experiments. In experiment 1, lipid and nitrate were fed alone with two different and contrasting basal diets to finishing beef cattle. In the second experiment, lipid and nitrate were fed alone or in combination with a single basal diet. The sensory properties and retail colour shelf life of loin muscle samples obtained were then characterized. Overall, neither lipid nor nitrate had any adverse effects on sensory properties or colour shelf life of loin muscle.


Assuntos
Ração Animal/análise , Bovinos/crescimento & desenvolvimento , Metano/metabolismo , Carne Vermelha/análise , Poluição do Ar/prevenção & controle , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos/metabolismo , Cor , Dieta/veterinária , Gorduras na Dieta/metabolismo , Armazenamento de Alimentos , Músculo Esquelético , Nitratos/farmacologia
13.
Meat Sci ; 157: 107871, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31254803

RESUMO

Steaks of 74 animals from 3 young bull breeds (Aberdeen Angus, Limousin and Blond d'Aquitaine) were cooked at two end-point cooking temperatures (55 and 74 °C) and evaluated for tenderness by trained panelists from France (FR) and the United Kingdom (UK). Using principal component regressions, the tenderness scores of each breed, country origin of the panelists and cooking temperature were linked with the abundances of 21 protein biomarkers belonging to five biological pathways. Twelve regression equations were built and explained 68 to 95% of tenderness variability. A high dissimilarity in the retained biomarkers was observed among the equations and differences exist among breeds, cooking temperatures and country origin of the panelists. Among the 21 biomarkers, 6 proteins including structural (MyHC-I, MyHC-IIa, MyHC-IIx), oxidative stress (DJ-1, PRDX6) and proteolysis (CAPN1) were retained robustly in positive or negative directions in the tenderization process of Longissimus thoracis, regardless the breed, the end-point cooking temperature or the country origin of the panelist.


Assuntos
Biomarcadores/química , Culinária/métodos , Carne Vermelha/análise , Animais , Bovinos , Preferências Alimentares , França , Humanos , Masculino , Músculo Esquelético/química , Análise de Componente Principal/métodos , Proteoma/análise , Temperatura , Reino Unido
14.
Front Genet ; 10: 927, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31649720

RESUMO

The Galway sheep population is the only native Irish sheep breed and this livestock genetic resource is currently categorised as 'at-risk'. In the present study, comparative population genomics analyses of Galway sheep and other sheep populations of European origin were used to investigate the microevolution and recent genetic history of the breed. These analyses support the hypothesis that British Leicester sheep were used in the formation of the Galway. When compared to conventional and endangered breeds, the Galway breed was intermediate in effective population size, genomic inbreeding and runs of homozygosity. This indicates that, although the Galway breed is declining, it is still relatively genetically diverse and that conservation and management plans informed by genomic information may aid its recovery. The Galway breed also exhibited distinct genomic signatures of artificial or natural selection when compared to other breeds, which highlighted candidate genes that may be involved in production and health traits.

15.
Living Rev Sol Phys ; 15(1): 1, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30872980

RESUMO

This paper focuses on the interactions between the fast solar wind from coronal holes and the intervening slower solar wind, leading to the creation of stream interaction regions that corotate with the Sun and may persist for many solar rotations. Stream interaction regions have been observed near 1 AU, in the inner heliosphere (at ∼ 0.3 -1 AU) by the Helios spacecraft, in the outer and distant heliosphere by the Pioneer 10 and 11 and Voyager 1 and 2 spacecraft, and out of the ecliptic by Ulysses, and these observations are reviewed. Stream interaction regions accelerate energetic particles, modulate the intensity of Galactic cosmic rays and generate enhanced geomagnetic activity. The remote detection of interaction regions using interplanetary scintillation and white-light imaging, and MHD modeling of interaction regions will also be discussed.

16.
Front Genet ; 9: 51, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29520297

RESUMO

Kerry cattle are an endangered landrace heritage breed of cultural importance to Ireland. In the present study we have used genome-wide SNP array data to evaluate genomic diversity within the Kerry population and between Kerry cattle and other European breeds. Patterns of genetic differentiation and gene flow among breeds using phylogenetic trees with ancestry graphs highlighted historical gene flow from the British Shorthorn breed into the ancestral population of modern Kerry cattle. Principal component analysis (PCA) and genetic clustering emphasised the genetic distinctiveness of Kerry cattle relative to comparator British and European cattle breeds. Modelling of genetic effective population size (Ne) revealed a demographic trend of diminishing Ne over time and that recent estimated Ne values for the Kerry breed may be less than the threshold for sustainable genetic conservation. In addition, analysis of genome-wide autozygosity (FROH) showed that genomic inbreeding has increased significantly during the 20 years between 1992 and 2012. Finally, signatures of selection revealed genomic regions subject to natural and artificial selection as Kerry cattle adapted to the climate, physical geography and agro-ecology of southwest Ireland.

17.
Nat Commun ; 9(1): 5414, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30575762

RESUMO

Internal flow behaviour during melt-pool-based metal manufacturing remains unclear and hinders progression to process optimisation. In this contribution, we present direct time-resolved imaging of melt pool flow dynamics from a high-energy synchrotron radiation experiment. We track internal flow streams during arc welding of steel and measure instantaneous flow velocities ranging from 0.1 m s-1 to 0.5 m s-1. When the temperature-dependent surface tension coefficient is negative, bulk turbulence is the main flow mechanism and the critical velocity for surface turbulence is below the limits identified in previous theoretical studies. When the alloy exhibits a positive temperature-dependent surface tension coefficient, surface turbulence occurs and derisory oxides can be entrapped within the subsequent solid as result of higher flow velocities. The widely used arc welding and the emerging arc additive manufacturing routes can be optimised by controlling internal melt flow through adjusting surface active elements.

18.
Abdom Radiol (NY) ; 42(12): 2933-2939, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28660332

RESUMO

PURPOSE: To determine whether virtual monochromatic imaging (VMI) increases detectability of noncalcified gallstones on dual-energy CT (DECT) compared with conventional CT imaging. MATERIALS AND METHODS: This retrospective IRB-approved, HIPAA-compliant study included consecutive patients who underwent DECT of the abdomen in the Emergency Department during a 30-month period (July 1, 2013-December 31, 2015), with a comparison US or MR within 1-year. 51 patients (36F, 15M; mean age 52 years) fulfilled the inclusion criteria. All DECT were acquired on a dual-source 128 × 2 slice scanner using either 80/Sn140 or 100/Sn140 kVp pairs. Source images at high and low kVp were used for DE post-processing with VMI. Within 3 mm reconstructed images, regions of interest of 0.5 cm2 were placed on noncalcified gallstones and bile to record hounsfield units (HU) at VMI energy levels ranging between 40 and 190 keV. RESULTS: Noncalcified gallstones uniformly demonstrated lowest HU at 40 keV and increase at higher keV; the HU of bile varied at higher keV. Few of the noncalcified stones are visible at 70 keV (simulating a conventional 120 kVp scan), with measured contrast (bile-stone HU difference) <10 HU in 78%, 10-20 HU in 20%, and >20 HU in 2%. Contrast was maximal at 40 keV, where 100% demonstrated >20 HU difference from surrounding bile, 75% >44 HU difference, and 50% >60 HU difference. A paired t test demonstrated a significant difference (p < 0.0001) between this stone-bile contrast at 40 vs. 70 keV and 70 vs. 190 keV. CONCLUSION: Low keV virtual monochromatic imaging increased conspicuity of noncalcified gallstones, improving their detectability.


Assuntos
Cálculos Biliares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia
19.
Meat Sci ; 130: 69-80, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28433853

RESUMO

There is considerable interest in enhancing beneficial fatty acids, particularly 18:3n-3, conjugated linoleic acid and long chain n-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in beef to provide benefits to human health. Here, the potential to enhance these fatty acids by feeding a n-3 polyunsaturated fatty acid (PUFA)-rich plant extract (PX) from lucerne is presented. Cattle (n=8/diet) were assigned to the following finishing diets: straw and concentrate (S-CC); straw and concentrate containing 25% PX and 2000IUvitaminE/kg PX-concentrate (S-PXC); grass silage (GS); GS plus 75gPX/kg dry matter intake (DMI) (GS-LPX) or GS plus 150g PX/kg DMI (GS-HPX). Addition of PX to concentrates or GS increased the n-3 fatty acid content of loin muscle and had favourable effects on the n-6:n-3 PUFA ratio (P<0.05), without detrimental effects on loin muscle sensory characteristics.


Assuntos
Ração Animal/análise , Ácidos Graxos/análise , Medicago sativa , Carne Vermelha/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Dieta/veterinária , Humanos , Masculino , Músculo Esquelético/química , Extratos Vegetais , Silagem
20.
Food Chem ; 235: 86-97, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28554651

RESUMO

Fatty acids, volatile compounds and sensory attributes of beef from bulls fed concentrates to slaughter (C), grass silage for 120days (GS) followed by C (GSC), or GS followed by 100days at pasture and then C (GSPC), and slaughtered at 3 target carcass weights, were determined. Total intramuscular fat (IMF) was lower for GSPC than for GSC and C. C18:3n-3 concentration and polyunsaturated fatty acid (PUFA) to saturated fatty acid (SFA) ratio were higher and C18:2n-6 and monounsaturated fatty acid concentrations and n-6:n-3 PUFA ratio lower for GSPC than C. C16:0, C18:0 and C18:1c9 increased with carcass weight when expressed quantitatively, but not when expressed proportionately. Hexanal concentration was higher and 2-methyl-1-butanol and toluene lower for C and GSC than for GSPC. Overall liking was negatively correlated with C20:5n-3 and PUFA/SFA ratio, but differences in sensory attributes (tenderness, flavour liking, overall liking) were most strongly correlated with IMF.


Assuntos
Ácidos Graxos/análise , Poaceae , Carne Vermelha/normas , Silagem , Animais , Bovinos , Dieta/veterinária , Masculino
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