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1.
Nature ; 600(7889): 450-455, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34912089

RESUMO

Early to Middle Miocene sea-level oscillations of approximately 40-60 m estimated from far-field records1-3 are interpreted to reflect the loss of virtually all East Antarctic ice during peak warmth2. This contrasts with ice-sheet model experiments suggesting most terrestrial ice in East Antarctica was retained even during the warmest intervals of the Middle Miocene4,5. Data and model outputs can be reconciled if a large West Antarctic Ice Sheet (WAIS) existed and expanded across most of the outer continental shelf during the Early Miocene, accounting for maximum ice-sheet volumes. Here we provide the earliest geological evidence proving large WAIS expansions occurred during the Early Miocene (~17.72-17.40 Ma). Geochemical and petrographic data show glacimarine sediments recovered at International Ocean Discovery Program (IODP) Site U1521 in the central Ross Sea derive from West Antarctica, requiring the presence of a WAIS covering most of the Ross Sea continental shelf. Seismic, lithological and palynological data reveal the intermittent proximity of grounded ice to Site U1521. The erosion rate calculated from this sediment package greatly exceeds the long-term mean, implying rapid erosion of West Antarctica. This interval therefore captures a key step in the genesis of a marine-based WAIS and a tipping point in Antarctic ice-sheet evolution.


Assuntos
Camada de Gelo , Elevação do Nível do Mar/história , Água do Mar/análise , Regiões Antárticas , Modelos Climáticos , História Antiga
2.
Phys Rev Lett ; 131(10): 101002, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739367

RESUMO

We report the first result of a direct search for a cosmic axion background (CaB)-a relativistic background of axions that is not dark matter-performed with the axion haloscope, the Axion Dark Matter eXperiment (ADMX). Conventional haloscope analyses search for a signal with a narrow bandwidth, as predicted for dark matter, whereas the CaB will be broad. We introduce a novel analysis strategy, which searches for a CaB induced daily modulation in the power measured by the haloscope. Using this, we repurpose data collected to search for dark matter to set a limit on the axion photon coupling of a CaB originating from dark matter cascade decay via a mediator in the 800-995 MHz frequency range. We find that the present sensitivity is limited by fluctuations in the cavity readout as the instrument scans across dark matter masses. Nevertheless, we suggest that these challenges can be surmounted using superconducting qubits as single photon counters, and allow ADMX to operate as a telescope searching for axions emerging from the decay of dark matter. The daily modulation analysis technique we introduce can be deployed for various broadband rf signals, such as other forms of a CaB or even high-frequency gravitational waves.

3.
Tech Coloproctol ; 26(11): 851-862, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35596904

RESUMO

BACKGROUND: Formation of a defunctioning loop ileostomy is common after mid and low rectal resection. Historically, they were reversed between 3 and 6 months after initial resection. Recently, earlier closure (< 14 days) has been suggested by some current randomised controlled trials. The aim of this study was to investigate the effect of early stoma closure on surgical and patient outcomes. METHODS: A systematic review of the current randomised controlled trial literature comparing early and standard ileostomy closure after rectal surgery was performed. Specifically, we examined surgical outcomes including; morbidity, mortality and quality of life. RESULTS: Six studies met the predefined criteria and were included in our analysis. 275 patients underwent early stoma closure compared with 259 patients having standard closure. Overall morbidity was similar between both groups (25.5% vs. 21.6%) (OR, 1.47; 95% CI 0.75-2.87). However, there tended to be more reoperations (8.4 vs. 4.2%) (OR, 2.02, 95% CI 0.99-4.14) and small bowel obstructions/postoperative ileus (9.3% vs. 4.4%) (OR 0.44, 95% CI 0.22-0.90) in the early closure group, but no difference across the other domains. CONCLUSIONS: Early closure appears to be a feasible in highly selective cases after good perioperative counselling and shared decision-making. Further research on quality of life outcomes and long term benefits is necessary to help define which patients are suitable candidates for early closure.


Assuntos
Ileostomia , Neoplasias Retais , Humanos , Ileostomia/efeitos adversos , Ileostomia/métodos , Íleus , Complicações Pós-Operatórias/epidemiologia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Retais/cirurgia
4.
Phys Rev Lett ; 127(26): 261803, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35029490

RESUMO

We report the results from a haloscope search for axion dark matter in the 3.3-4.2 µeV mass range. This search excludes the axion-photon coupling predicted by one of the benchmark models of "invisible" axion dark matter, the Kim-Shifman-Vainshtein-Zakharov model. This sensitivity is achieved using a large-volume cavity, a superconducting magnet, an ultra low noise Josephson parametric amplifier, and sub-Kelvin temperatures. The validity of our detection procedure is ensured by injecting and detecting blind synthetic axion signals.

5.
Phys Rev Lett ; 124(24): 241101, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32639799

RESUMO

Axions are a promising cold dark matter candidate. Haloscopes, which use the conversion of axions to photons in the presence of a magnetic field to detect axions, are the basis of microwave cavity searches such as the Axion Dark Matter eXperiment (ADMX). To search for lighter, low frequency axions in the sub- 2×10^{-7} eV (50 MHz) range, a tunable lumped-element LC circuit has been proposed. For the first time, through ADMX SLIC (Superconducting LC Circuit Investigating Cold Axions), a resonant LC circuit was used to probe this region of axion mass-coupling space. The detector used a superconducting LC circuit with piezoelectric driven capacitive tuning. The axion mass and corresponding frequency ranges 1.7498-1.7519×10^{-7} eV (42.31-42.36 MHz), 1.7734-1.7738×10^{-7} eV (42.88-42.89 MHz), and 1.8007-1.8015×10^{-7} eV (43.54-43.56 MHz) were covered at magnetic fields of 4.5 T, 5.0 T, and 7.0 T, respectively. Exclusion results from the search data, for coupling below 10^{-12} GeV^{-1}, are presented.

6.
Phys Rev Lett ; 124(10): 101303, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216421

RESUMO

This Letter reports on a cavity haloscope search for dark matter axions in the Galactic halo in the mass range 2.81-3.31 µeV. This search utilizes the combination of a low-noise Josephson parametric amplifier and a large-cavity haloscope to achieve unprecedented sensitivity across this mass range. This search excludes the full range of axion-photon coupling values predicted in benchmark models of the invisible axion that solve the strong CP problem of quantum chromodynamics.

7.
Ir Med J ; 112(6): 946, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-31535835

RESUMO

Background Pseudomonas aeruginosa (PA) infection is associated with an increased morbidity and adverse prognosis in children with Cystic Fibrosis(CF). The aim of the study was to evaluate the prevalence and characteristics of PA over a ten year period at a single paediatric tertiary referral centre in Ireland. Methods This was a retrospective cross-sectional study. Patient's case notes, microbiology laboratory results and CF Registry of Ireland(CFRI) data were used to collect the data. Results The overall chronic PA infection prevalence was 28.1%(45/160) in 2004 and 21.3%(35/164) in 2014. In 2004, 54/160(33.8%) patients were never infected with PA, 27/160(16.9%) were free for 12 months and 34/160(21.3%) were intermittently infected. In 2014; 80/164(49%) patients, 38/164(23.2%) and 11/164(6.7%) were never infected, free for 12 months and intermittently infected respectively. Conclusion There has been a decline in the overall prevalence of PA infection and a change in the pattern of prevalence over the last decade at our Centre.


Assuntos
Fibrose Cística/complicações , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Fibrose Cística/epidemiologia , Fibrose Cística/fisiopatologia , Volume Expiratório Forçado , Humanos , Lactente , Irlanda/epidemiologia , Prevalência , Infecções por Pseudomonas/etiologia , Estudos Retrospectivos
8.
Phys Rev Lett ; 120(15): 151301, 2018 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-29756850

RESUMO

This Letter reports the results from a haloscope search for dark matter axions with masses between 2.66 and 2.81 µeV. The search excludes the range of axion-photon couplings predicted by plausible models of the invisible axion. This unprecedented sensitivity is achieved by operating a large-volume haloscope at subkelvin temperatures, thereby reducing thermal noise as well as the excess noise from the ultralow-noise superconducting quantum interference device amplifier used for the signal power readout. Ongoing searches will provide nearly definitive tests of the invisible axion model over a wide range of axion masses.

9.
Phys Rev Lett ; 121(26): 261302, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30636160

RESUMO

The µeV axion is a well-motivated extension to the standard model. The Axion Dark Matter eXperiment (ADMX) collaboration seeks to discover this particle by looking for the resonant conversion of dark-matter axions to microwave photons in a strong magnetic field. In this Letter, we report results from a pathfinder experiment, the ADMX "Sidecar," which is designed to pave the way for future, higher mass, searches. This testbed experiment lives inside of and operates in tandem with the main ADMX experiment. The Sidecar experiment excludes masses in three widely spaced frequency ranges (4202-4249, 5086-5799, and 7173-7203 MHz). In addition, Sidecar demonstrates the successful use of a piezoelectric actuator for cavity tuning. Finally, this publication is the first to report data measured using both the TM_{010} and TM_{020} modes.

10.
Ir Med J ; 116(No.1): 2, 2023 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-36917085
11.
Eur J Clin Microbiol Infect Dis ; 36(7): 1317-1324, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28247153

RESUMO

The aim of this study was to compare an in-house real-time PCR assay, with bacterial culture as the reference, for the diagnosis of late onset group B Streptococcal (GBS) disease. This was a retrospective review. All children aged 7-90 days presenting to four paediatric centres that had a blood or CSF sample tested by GBS PCR were included. Of 7,686 blood and 2,495 cerebrospinal fluid (CSF) samples from patients of all ages received for PCR testing, 893 and 859 samples were eligible for the study, respectively. When compared to culture, the sensitivity of blood PCR was 65% (13/20) in comparison to the CSF PCR test which was 100% (5/5). Ten of 23 PCR-positive blood samples and 17 of 22 PCR-positive CSF samples were culture negative. The median threshold Ct values for culture-positive/PCR-positive CSF samples was lower than that of culture-negative/PCR-positive CSF samples (p = 0.08). Clinical details of 17 available cases that were culture negative/PCR positive were reviewed; seven were deemed to be definite cases, eight were probable and two were possible. The results showed that detection of GBS by PCR is useful for CSF samples from infants aged 7-90 days with suspected meningitis; however, analysis of blood samples by PCR is of limited value as a routine screening test for late onset GBS sepsis and should not replace bacterial culture.


Assuntos
Bacteriemia/diagnóstico , Técnicas Bacteriológicas/métodos , Transtornos de Início Tardio/diagnóstico , Meningites Bacterianas/diagnóstico , Reação em Cadeia da Polimerase/métodos , Infecções Estreptocócicas/diagnóstico , Streptococcus agalactiae/isolamento & purificação , Sangue/microbiologia , Líquido Cefalorraquidiano/microbiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
J Hum Nutr Diet ; 29(5): 549-75, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27272325

RESUMO

BACKGROUND: The first British Dietetic Association (BDA) guidelines for the dietary management of irritable bowel syndrome (IBS) in adults were published in 2012. Subsequently, there has been a wealth of new research. The aim of this work was to systematically review the evidence for the role of diet in the management of IBS and to update the guidelines. METHODS: Twelve questions relating to diet and IBS were defined based on review of the previous guideline questions, current evidence and clinical practice. Chosen topics were on healthy eating and lifestyle (alcohol, caffeine, spicy food, elimination diets, fat and fluid intakes and dietary habits), milk and dairy, dietary fibre, fermentable carbohydrates, gluten, probiotics and elimination diets/food hypersensitivity. Data sources were CINAHL, Cochrane Register of Controlled Trials, Embase, Medline, Scopus and Web of Science up to October 2015. Studies were assessed independently in duplicate using risk of bias tools specific to each included study based on inclusion and exclusion criteria for each question. National Health and Medical Research Council grading evidence levels were used to develop evidence statements and recommendations, in accordance with Practice-based Evidence in Nutrition Global protocol used by the BDA. RESULTS: Eighty-six studies were critically appraised to generate 46 evidence statements, 15 clinical recommendations and four research recommendations. The IBS dietary algorithm was simplified to first-line (healthy eating, provided by any healthcare professional) and second-line [low FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) to be provided by dietitian] dietary advice. CONCLUSIONS: These guidelines provide updated comprehensive evidence-based details to achieve the successful dietary management of IBS in adults.


Assuntos
Dieta Saudável , Medicina Baseada em Evidências , Microbioma Gastrointestinal , Síndrome do Intestino Irritável/dietoterapia , Adulto , Carboidratos da Dieta/metabolismo , Carboidratos da Dieta/uso terapêutico , Suplementos Nutricionais , Dietética , Disbiose/tratamento farmacológico , Disbiose/microbiologia , Disbiose/fisiopatologia , Disbiose/prevenção & controle , Fermentação , Estilo de Vida Saudável , Humanos , Síndrome do Intestino Irritável/etiologia , Síndrome do Intestino Irritável/microbiologia , Síndrome do Intestino Irritável/prevenção & controle , Metanálise como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Sociedades Científicas , Reino Unido
13.
J Anim Breed Genet ; 133(5): 334-46, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27357473

RESUMO

Most genomic prediction studies fit only additive effects in models to estimate genomic breeding values (GEBV). However, if dominance genetic effects are an important source of variation for complex traits, accounting for them may improve the accuracy of GEBV. We investigated the effect of fitting dominance and additive effects on the accuracy of GEBV for eight egg production and quality traits in a purebred line of brown layers using pedigree or genomic information (42K single-nucleotide polymorphism (SNP) panel). Phenotypes were corrected for the effect of hatch date. Additive and dominance genetic variances were estimated using genomic-based [genomic best linear unbiased prediction (GBLUP)-REML and BayesC] and pedigree-based (PBLUP-REML) methods. Breeding values were predicted using a model that included both additive and dominance effects and a model that included only additive effects. The reference population consisted of approximately 1800 animals hatched between 2004 and 2009, while approximately 300 young animals hatched in 2010 were used for validation. Accuracy of prediction was computed as the correlation between phenotypes and estimated breeding values of the validation animals divided by the square root of the estimate of heritability in the whole population. The proportion of dominance variance to total phenotypic variance ranged from 0.03 to 0.22 with PBLUP-REML across traits, from 0 to 0.03 with GBLUP-REML and from 0.01 to 0.05 with BayesC. Accuracies of GEBV ranged from 0.28 to 0.60 across traits. Inclusion of dominance effects did not improve the accuracy of GEBV, and differences in their accuracies between genomic-based methods were small (0.01-0.05), with GBLUP-REML yielding higher prediction accuracies than BayesC for egg production, egg colour and yolk weight, while BayesC yielded higher accuracies than GBLUP-REML for the other traits. In conclusion, fitting dominance effects did not impact accuracy of genomic prediction of breeding values in this population.


Assuntos
Cruzamento , Galinhas/genética , Animais , Teorema de Bayes , Galinhas/classificação , Genes Dominantes , Linhagem , Fenótipo , Polimorfismo de Nucleotídeo Único
14.
Poult Sci ; 95(2): 466-71, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26706355

RESUMO

Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm.


Assuntos
Envelhecimento , Análise Química do Sangue/veterinária , Galinhas/fisiologia , Animais , Gasometria/veterinária , Galinhas/sangue , Galinhas/genética , Feminino , Valores de Referência
15.
Eur J Clin Microbiol Infect Dis ; 34(12): 2413-20, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26433745

RESUMO

Group B streptococcus (GBS) is a leading cause of invasive disease in infants. Accurate and rapid diagnosis is crucial to reduce morbidity and mortality. Real-time polymerase chain reaction (PCR) targeting the dltR gene was utilised for the direct detection of GBS DNA in blood and cerebrospinal fluid (CSF) from infants at an Irish maternity hospital. A retrospective review of laboratory and patient records during the period 2011-2013 was performed in order to evaluate PCR and culture for the diagnosis of invasive GBS disease. A total of 3570 blood and 189 CSF samples from 3510 infants had corresponding culture and PCR results. Culture and PCR exhibited concordance in 3526 GBS-negative samples and 13 (25%) GBS-positive samples (n = 53). Six (11%) and 34 (64%) GBS-positive samples were positive only in culture or PCR, respectively. Culture and PCR identified more GBS-positive infants (n = 47) than PCR (n = 43) or culture (n = 16) alone. Using culture as the reference standard, the sensitivity, specificity, and positive and negative predictive values for PCR on blood samples were 71.4%, 99.2%, 25% and 99.9%, and for CSF samples, they were 60%, 97.8%, 42.9% and 98.9%, respectively. The sensitivity and positive predictive values were improved (blood: 84.6% and 55%; CSF: 77.8% and 100%, respectively) when maternal risk factors and other laboratory test results were considered. The findings in this study recommend the use of direct GBS real-time PCR for the diagnosis of GBS infection in infants with a clinical suspicion of invasive disease and as a complement to culture, but should be interpreted in the light of other laboratory and clinical findings.


Assuntos
Técnicas Bacteriológicas/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Infecções Estreptocócicas/diagnóstico , Streptococcus agalactiae/isolamento & purificação , Sangue/microbiologia , Líquido Cefalorraquidiano/microbiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Streptococcus agalactiae/genética , Streptococcus agalactiae/crescimento & desenvolvimento
16.
BJOG ; 122(5): 663-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24862293

RESUMO

OBJECTIVE: To determine the incidence of maternal bacteraemia during pregnancy and for 6 weeks postpartum, describe the gestation/stage at which sepsis occurs, the causative microorganisms, antibiotic resistance and review maternal, fetal and neonatal outcome. DESIGN: Prospective review. SETTING: Two tertiary referral, maternity hospitals in Dublin, Ireland. POPULATION: During 2005-2012 inclusive, 150 043 pregnant women attended and 24.4% of infants born in Ireland were delivered at the hospitals. METHODS: Demographic, clinical, microbiological and outcome data was collected from women with sepsis and compared with controls. MAIN OUTCOME MEASURES: Incidence, bacterial aetiology, gestation/stage at delivery, mode of delivery, antibiotic resistance, admission to augmented care, maternal, fetal and neonatal outcome. RESULTS: The sepsis rate was 1.81 per 1000 pregnant women. Escherichia coli was the predominant pathogen, followed by Group B Streptococcus. Sepsis was more frequent among nulliparous women (odds ratio [OR] 1.39; 95% confidence interval [CI] 1.07-1.79) and multiple births (OR 2.04; 95% CI 0.98-4.08). Seventeen percent of sepsis episodes occurred antenatally, 36% intrapartum and 47% postpartum. The source of infection was the genital tract in 61% (95% CI 55.1-66.6) of patients and the urinary tract in 25% (95% CI 20.2-30.5). Sepsis was associated with preterm delivery (OR 2.81; 95% CI 1.99-3.96) and a high perinatal mortality rate (OR =5.78; 95% CI 2.89-11.21). Almost 14% of women required admission to augmented care. The most virulent organisms were Group A Streptococcus linked to postpartum sepsis at term and preterm Escherichia coli sepsis. CONCLUSIONS: Maternal sepsis is associated with preterm birth, a high perinatal mortality rate and nulliparous women.


Assuntos
Mortalidade Infantil , Mortalidade Materna , Mães , Trabalho de Parto Prematuro/epidemiologia , Mortalidade Perinatal , Complicações Infecciosas na Gravidez/epidemiologia , Sepse/epidemiologia , Adulto , Feminino , Maternidades/estatística & dados numéricos , Humanos , Incidência , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Irlanda/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/etiologia , Complicações Infecciosas na Gravidez/mortalidade , Estudos Prospectivos , Medição de Risco , Sepse/etiologia , Sepse/mortalidade
17.
Poult Sci ; 94(2): 195-206, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25595478

RESUMO

The objectives of this study were to evaluate the effects of feeding 5 different energy and nutrient dense diets to Hy-Line W-36 hens on long-term performance and economics. A total of 480 19 wk old Hy-Line W-36 Single Comb White Leghorn hens were weighed and randomly allocated to 6 replicate groups of 16 hens each (2 adjacent cages containing 8 hens per cage, 60.9×58.4 cm) per dietary treatment in a randomized complete block design. The hens were fed 5 treatment diets formulated to contain 85, 90, 95, 100, and 105% of the energy and nutrient recommendations stated in the 2009 Hy-Line Variety W-36 Commercial Management Guide. Production performance was measured for 52 wk from 19 to 70 wk age. Over the course of the trial, a significant increasing linear response to increasing energy and nutrient density was seen for hen-day egg production, egg weight, egg mass, feed efficiency, energy intake, and body weight (BW). Feed intake showed no significant linear level response to increasing energy and nutrient density except during the early production cycle. No consistent responses were noted for egg quality, percent yolk, and percent egg solids throughout the study. Significant linear responses due to energy and nutrient density were seen for egg income, feed cost, and income minus feed cost. In general, as energy and nutrient density increased, egg income and feed cost per hen increased, but income minus feed cost decreased. Overall, these results indicate that feeding Hy-Line W-36 hens increasing energy and nutrient-dense diets will increase egg production, egg weight, egg mass, feed efficiency, energy intake, BW, egg income, and feed cost, but decrease egg income minus feed cost. However, these benefits do not take effect in early production and seem to be most effective in later stages of the production cycle, perhaps "priming" the birds for better egg-production persistency with age.


Assuntos
Ração Animal/análise , Galinhas/fisiologia , Dieta/veterinária , Ingestão de Energia/fisiologia , Oviposição/fisiologia , Envelhecimento , Ração Animal/economia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ovos/economia
18.
Phys Rev Lett ; 112(13): 131301, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24745401

RESUMO

We show that dark matter axions cause an oscillating electric current to flow along magnetic field lines. The oscillating current induced in a strong magnetic field B0 produces a small magnetic field Ba. We propose to amplify and detect Ba using a cooled LC circuit and a very sensitive magnetometer. This appears to be a suitable approach to searching for axion dark matter in the 10(-7) to 10(-9) eV mass range.

19.
J Anim Breed Genet ; 131(3): 173-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24628796

RESUMO

Discovery of genes with large effects on economically important traits has for many years been of interest to breeders. The development of SNP panels which cover the whole genome with high density and, more importantly, that can be genotyped on large numbers of individuals at relatively low cost, has opened new opportunities for genome-wide association studies (GWAS). The objective of this study was to find genomic regions associated with egg production and quality traits in layers using analysis methods developed for the purpose of whole genome prediction. Genotypes on over 4500 birds and phenotypes on over 13,000 hens from eight generations of a brown egg layer line were used. Birds were genotyped with a custom 42K Illumina SNP chip. Recorded traits included two egg production and 11 egg quality traits (puncture score, albumen height, yolk weight and shell colour) at early and late stages of production, as well as body weight and age at first egg. Egg weight was previously analysed by Wolc et al. (2012). The Bayesian whole genome prediction model--BayesB (Meuwissen et al. 2001) was used to locate 1 Mb regions that were most strongly associated with each trait. The posterior probability of a 1 Mb window contributing to genetic variation was used as the criterion for suggesting the presence of a quantitative trait locus (QTL) in that window. Depending upon the trait, from 1 to 7 significant (posterior probability >0.9) 1 Mb regions were found. The largest QTL, a region explaining 32% of genetic variance, was found on chr4 at 78 Mb for body weight but had pleiotropic effects on other traits. For the other traits, the largest effects were much smaller, explaining <7% of genetic variance, with regions on chromosomes 2, 12 and 17 explaining above 5% of genetic variance for albumen height, shell colour and egg production, respectively. In total, 45 of 1043 1 Mb windows were estimated to have a non-zero effect with posterior probability > 0.9 for one or more traits.


Assuntos
Galinhas/genética , Galinhas/fisiologia , Estudo de Associação Genômica Ampla , Oviposição/genética , Animais , Feminino , Variação Genética , Genômica
20.
Phys Rev Lett ; 110(13): 137201, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581363

RESUMO

By means of ac magnetic-susceptibility measurements, we find evidence for a new magnetic phase of Tb2Ti2O7 below about 140 mK in zero magnetic field. In magnetic fields parallel to [111], this phase is characterized by frequency- and amplitude-dependent susceptibility and extremely slow spin dynamics. In the zero-temperature limit, it extends to about 67 mT (the internal field H(int)≃52 mT), at which it makes transition to another phase. The field dependence of the susceptibility of this second phase, which extends to about 0.60 T (H(int)≃0.54 T) in the zero-temperature limit, indicates the presence of a weak magnetization plateau below about 50 mK, as has been predicted by a single-tetrahedron four-spin model, suggesting that the second phase is a quantum kagome ice.

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