The neutron and its hypothetical mirror counterpart, a sterile state degenerate in mass, could spontaneously mix in a process much faster than the neutron β-decay. Two groups have performed a series ...of experiments in search of neutron – mirror-neutron (
n
−
n
′) oscillations. They reported no evidence, thereby setting stringent limits on the oscillation time τ
nn
′
. Later, these data sets have been further analyzed by Berezhiani et al.(2009–2017), and signals, compatible with
n
−
n
′ oscillations in the presence of mirror magnetic fields, have been reported. The Neutron Electric Dipole Moment Collaboration based at the Paul Scherrer Institute performed a new series of experiments to further test these signals. In this paper, we describe and motivate our choice of run configurations with an optimal filling time of 29 s, storage times of 180 s and 380 s, and applied magnetic fields of 10 μT and 20 μT. The choice of these run configurations ensures a reliable overlap in settings with the previous efforts and also improves the sensitivity to test the signals. We also elaborate on the technique of normalizing the neutron counts, making such a counting experiment at the ultra-cold neutron source at the Paul Scherrer Institute possible. Furthermore, the magnetic field characterization to meet the requirements of this
n
−
n
′ oscillation search is demonstrated. Finally, we show that this effort has a statistical sensitivity to
n
−
n
′ oscillations comparable to the current leading constraints for
B
′ = 0.
The objective of this study was to evaluate the genetic variability of body condition score (BCS) in Nelore cows, and analyze its genetic correlations with mature weight (MW), mature height (MH) and ...gestation length (GL), in order to obtain information supporting the possible use of this score in breeding programs. The BCS was recorded on pregnancy diagnosis and ranged from 1 (very thin) to 5 (extremely fat). Adjusted means for MW, MH and GL according to the BCS classes were obtained using an univariate mixed model for each trait. Bayesian Inference using Gibbs Sampling was applied to estimate (co)variances components and genetic and phenotypic correlations, in two-trait analyses, considering a threshold animal model for BCS and a linear animal model for the other traits. Adjusted means for MW, MH and GL showed significant variation (p<0.0001) among BCS classes, indicating that cows with higher BCS have greater mature size, assessed by MW and MH measures, and longer GL than those with lower BCS. The BCS showed genetic variability, with posterior mean heritability of 0.23±0.05. Genetic correlations between the BCS with MW, MH and GL were 0.41±0.04; −0.06±0.03 and 0.10±0.02, respectively. Selection based on BCS should result in gain for body condition and, by indirect response, in changes in the same direction for cows MW. However, selection for BCS has little or no effect on MH and GL. So that BCS can effectively be used as a selection criterion of beef cows, further studies should be performed in order to obtain genetic associations with other economic traits.
•We show the correlations between body condition and other traits.•Cows with higher body condition presented a greater mature size.•The body condition shows genetic variability and responds to individual selection.•Indirect response on mature weight was expected by correlated response.•Selection for body condition has little effect on height and gestation length.
Caprine lentivirus in sheep milk and semen Lima, C.C.V.; Ayres, M.C.C.; Pinheiro, R.R. ...
Arquivo brasileiro de medicina veterinária e zootecnia,
04/2017, Letnik:
69, Številka:
2
Journal Article
Recenzirano
Odprti dostop
ABSTRACT With the objective of detecting the presence of caprine lentivirus (CLV) in ewe milk and in ram semen, ten matrixes and four reproducers experimentally infected with CLV were used. Samples ...of ewe milk were collected during the four months of lactation, five collections per animal, totaling 50 samples. Regarding the rams, eight semen collections were made per animal, during one year of experimentation, totaling 32 samples. The milk and semen samples were submitted to DNA extraction and the nested polymerase chain reaction test (nPCR) to detect CLV proviral DNA. Eight (16%) of the milk samples were positive in nPCR originating from two ewes. Only one (3.12%) semen sample was positive. The amplification products were sequenced, and were confirmed to be a CLV genomic sequence. Thus, the presence of CLV proviral DNA in sheep milk and semen was demonstrated, confirming the feasibility of infection between species, and alerting to the risk of spreading infections.
RESUMO Com o objetivo de detectar a presença do lentivírus caprino (LVC) no leite de ovelhas e no sêmen de carneiros, utilizaram-se 10 matrizes e quatro reprodutores infectados experimentalmente com o LVC. Foram coletadas amostras de leite das ovelhas durante os quatro meses de lactação, ocorrendo cinco coletas por animal, totalizando 50 amostras. Quanto aos carneiros, realizaram-se oito coletas de sêmen por animal, durante um ano de experimentação, totalizando 32 amostras. As amostras de leite e de sêmen foram submetidas à extração de DNA e à prova de reação em cadeia da polimerase do tipo nested (nPCR) visando à detecção de DNA proviral do LVC. Oito (16%) amostras de leite foram positivas na nPCR oriundas de duas ovelhas. Apenas uma (3,12%) amostra de sêmen apresentou positividade. Produtos da amplificação foram sequenciados, confirmando-se tratar de sequência genômica do LVC. Dessa forma, demonstrou-se a presença do DNA proviral do LVC em leite e sêmen de ovinos, confirmando a viabilidade da infecção entre espécies e, assim, alertando sobre o risco de que a infecção seja disseminada.
Correlated electron systems are highly susceptible to various forms of electronic order. By tuning the transition temperature towards absolute zero, striking deviations from conventional metallic ...(Fermi-liquid) behaviour can be realized. Evidence for electronic nematicity, a correlated electronic state with broken rotational symmetry, has been reported in a host of metallic systems
that exhibit this so-called quantum critical behaviour. In all cases, however, the nematicity is found to be intertwined with other forms of order, such as antiferromagnetism
or charge-density-wave order
, that might themselves be responsible for the observed behaviour. The iron chalcogenide FeSe
S
is unique in this respect because its nematic order appears to exist in isolation
, although until now, the impact of nematicity on the electronic ground state has been obscured by superconductivity. Here we use high magnetic fields to destroy the superconducting state in FeSe
S
and follow the evolution of the electrical resistivity across the nematic quantum critical point. Classic signatures of quantum criticality are revealed: an enhancement in the coefficient of the T
resistivity (due to electron-electron scattering) on approaching the critical point and, at the critical point itself, a strictly T-linear resistivity that extends over a decade in temperature T. In addition to revealing the phenomenon of nematic quantum criticality, the observation of T-linear resistivity at a nematic critical point also raises the question of whether strong nematic fluctuations play a part in the transport properties of other 'strange metals', in which T-linear resistivity is observed over an extended regime in their respective phase diagrams.
Placenta accreta spectrum is impacting maternal health outcomes globally and its prevalence is likely to increase. Maternal outcomes depend on identification of the condition before or during ...delivery and, in particular, on the differential diagnosis between its adherent and invasive forms. However, accurate estimation of its prevalence and outcome is currently problematic because of the varying use of clinical criteria to define it at birth and the lack of detailed pathologic examination in most series. Adherence to this new International Federation of Gynecology and Obstetrics (FIGO) classification should improve future systematic reviews and meta‐analyses and provide more accurate epidemiologic data which are essential to develop new management strategies.
Accurate identification and reporting of the different grades of placenta accreta spectrum are essential to the development of management strategies for this complex obstetric complication.
We report on the strategy used to optimize the sensitivity of our search for a neutron electric dipole moment at the Paul Scherrer Institute. Measurements were made upon ultracold neutrons stored ...within a single chamber at the heart of our apparatus. A mercury cohabiting magnetometer together with an array of cesium magnetometers were used to monitor the magnetic field, which was controlled and shaped by a series of precision field coils. In addition to details of the setup itself, we describe the chosen path to realize an appropriate balance between achieving the highest statistical sensitivity alongside the necessary control on systematic effects. The resulting irreducible sensitivity is better than 1 × 10
−26
e
cm. This contribution summarizes in a single coherent picture the results of the most recent publications of the collaboration.
Abstract
The gravitational potential φ = GM/Rc2 at the surface of the white dwarf G191-B2B is 10,000 times stronger than that at the Earth’s surface. Numerous photospheric absorption features are ...detected, making this a suitable environment to test theories in which the fundamental constants depend on gravity. We have measured the fine structure constant, α, at the white dwarf surface, used a newly calibrated Hubble Space Telescope STIS spectrum of G191-B2B, two new independent sets of laboratory Fe V wavelengths, and new atomic calculations of the sensitivity parameters that quantify Fe V wavelength dependency on α. The two results obtained are: Δα/α0 = (6.36 ± 0.35stat ± 1.84sys) × 10−5 and Δα/α0 = (4.21 ± 0.48stat ± 2.25sys) × 10−5. The measurements hint that the fine structure constant increases slightly in the presence of strong gravitational fields. A comprehensive search for systematic errors is summarised, including possible effects from line misidentifications, line blending, stratification of the white dwarf atmosphere, the quadratic Zeeman effect and electric field effects, photospheric velocity flows, long-range wavelength distortions in the HST spectrum, and variations in the relative Fe isotopic abundances. None fully account for the observed deviation but the systematic uncertainties are heavily dominated by laboratory wavelength measurement precision.
We analyzed the polymorphisms TFAM HaeIII, TFAM MboI and FABP4 MspA1I in three Nellore lines selected for growth in order to evaluate how selection affects the frequencies of these polymorphisms and ...evaluate their association with growth and carcass traits in Zebu cattle. Birth, weaning and yearling weights, rump height, longissimus muscle area, backfat thickness, and rump fat thickness were analyzed. The sample was constituted of animals from two lines selected for yearling weight (NeS and NeT), and a control line (NeC), established in 1980, at the São Paulo Instituto de Zootecnia. Two hundred and seventy-two heifers were genotyped for TFAM gene SNPs, and 325 heifers were genotyped for the FABP4 SNP. High frequencies were observed for the alleles A (TFAM HaeIII), C (TFAM MboI) and C (FABP4 MspA1I). Significant differences in allele frequencies between NeS and NeT were observed for the TFAM HaeIII, and between the line NeT and lines NeC and NeS for the FABP4 MspA1I SNP. Five haplotypes were observed for the two polymorphisms in the TFAM gene, haplotype AACC being the most frequent. None of the markers separately or according to haplotype was significantly associated with the growth and carcass traits. The low frequencies of alleles that are associated with high marbling scores and thick subcutaneous fat in taurine breeds might explain the low means for these traits in Nellore cattle.
Household Air Pollution (HAP) from biomass cooking fuels is a major cause of morbidity and mortality in low-income settings worldwide. In Nepal the use of open stoves with solid biomass fuels is the ...primary method of domestic cooking. To assess patterns of domestic air pollution we performed continuous measurement of carbon monoxide (CO) and particulate Matter (PM2.5) in 12 biomass fuel households in Janakpur, Nepal. We measured kitchen PM2.5 and CO concentrations at one-minute intervals for an approximately 48-h period using the TSI DustTrak II 8530/SidePak AM510 (TSI Inc, St. Paul MN, USA) or EL-USB-CO data logger (Lascar Electronics, Erie PA, USA) respectively. We also obtained information regarding fuel, stove and kitchen characteristics and cooking activity patterns. Household cooking was performed in two daily sessions (median total duration 4 h) with diurnal variability in pollutant concentrations reflecting morning and evening cooking sessions and peak concentrations associated with fire-lighting. We observed a strong linear relationship between PM2.5 measurements obtained by co-located photometric and gravimetric monitoring devices, providing local calibration factors of 4.9 (DustTrak) and 2.7 (SidePak). Overall 48-h average CO and PM2.5 concentrations were 5.4 (SD 4.3) ppm (12 households) and 417.6 (SD 686.4) μg/m3 (8 households), respectively, with higher average concentrations associated with cooking and heating activities. Overall average PM2.5 concentrations and peak 1-h CO concentrations exceeded WHO Indoor Air Quality Guidelines. Average hourly PM2.5 and CO concentrations were moderately correlated (r = 0.52), suggesting that CO has limited utility as a proxy measure for PM2.5 exposure assessment in this setting. Domestic indoor air quality levels associated with biomass fuel combustion in this region exceed WHO Indoor Air Quality standards and are in the hazardous range for human health.
•Intensive PM2.5 and CO monitoring was performed in 12 biomass fuel-using households in Janakpur.•Domestic cooking activity patterns and kitchen, stove and fuel characteristics were recorded.•Temporal PM2.5 and CO patterns demonstrated diurnal variability reflecting morning and evening cooking sessions.•Average PM2.5 and peak CO concentrations both exceeded World Health Organization (WHO) Indoor Air Quality Guidelines.•Concentrations of PM2.5 and CO were moderately correlated during cooking periods.
PDF
