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Bovine viral diarrhea virus (BVDV) is an important infectious disease agent that causes significant reproductive and economic losses in the cattle industry worldwide. Although BVDV infection is known to cause poor fertility in cattle, a greater part of the underlying mechanisms particularly associated with early reproductive losses are not clearly understood. Previous studies reported viral compromise of reproductive function in infected bulls. In females, BVDV infection is thought to be capable of killing the oocyte, embryo or fetus directly, or to induce lesions that result in fetal abortion or malformation. BVDV infections may also induce immune dysfunction, and predispose cattle to other diseases that cause poor health and fertility. Other reports also suggested BVDV-induced disruption of the reproductive endocrine system, and a disruption of leukocyte and cytokine functions in the reproductive organs. More recent studies have provided evidence of viral-induced suppression of endometrial innate immunity that may predispose to uterine disease. Furthermore, there is new evidence that BVDV may potentially disrupt the maternal recognition of pregnancy or the immune protection of the conceptus. This review brings together the previous reports with the more recent findings, and attempts to explain some of the mechanisms linking this important virus to infertility in cattle.
Triploid and pentaploid breeding is of great importance in agricultural production, but it is not always easy to obtain double ploidy parents. However, in fishes, chromosome ploidy is diversiform, which may provide natural parental resources for triploid and pentaploid breeding. Both tetraploid and hexaploid exist in Schizothorax fishes, which were thought to belong to different subfamilies with tetraploid Percocypris fishes in morphology, but they are sister genera in molecule. Fortunately, the pentaploid hybrid fishes have been successfully obtained by hybridization of Schizothorax wangchiachii (♀, 2n = 6X = 148) × Percocypris pingi (♂, 2n = 4X = 98). To understand the genetic and morphological difference among the hybrid fishes and their parents, four methods were used in this study: morphology, karyotype, red blood cell (RBC) DNA content determination and inter-simple sequence repeat (ISSR). In morphology, the hybrid fishes were steady, and between their parents with no obvious preference. The chromosome numbers of P. pingi have been reported as 2n = 4X = 98. In this study, the karyotype of S. wangchiachii was 2n = 6X = 148 = 36m + 34sm + 12st + 66t, while that the hybrid fishes was 2n = 5X = 123 = 39m + 28sm + 5st + 51t. Similarly, the RBC DNA content of the hybrid fishes was intermediate among their parents. In ISSR, the within-group genetic diversity of hybrid fishes was higher than that of their parents. Moreover, the genetic distance of hybrid fishes between P. pingi and S.wangchiachii was closely related to that of their parental ploidy, suggesting that parental genetic material stably coexisted in the hybrid fishes. This is the first report to show a stable pentaploid F1 hybrids produced by hybridization of a hexaploid and a tetraploid in aquaculture.
Three novel methods of x-ray spectrometry have been developed in recent years at Texas Tech University. These are:
1. Three crystal spectrometer
2. Two curved crystal spectrometer
3. Spherically bent crystal spectrometer.
In this paper the new design features, and experimental results will be discussed to indicate the usefulness of the new instruments. The three crystal spectrometer is a modified two crystal instrument. A third crystal is used to analyze the output of the two crystal spectrometer. The first two crystals are operated as a standard two crystal spectrometer. The third crystal is swept through the spectrum transmitted by the first two crystals for each setting of the first two crystals. The peak intensity of the third crystal sweep corresponds to the energy setting of the two crystal spectrometer, and is the intensity used to plot the spectral lines. The two curved crystal spectrometer utilizes two transmission spectrographs with radii having a 2:1 ratio in series, the crystal with the smaller radius being set so that its focal point falls on the Rowland circle of the larger radius crystal, This instrument has a very low background intensity and is suitable for precision scattering and diffraetion work. The spherically bent crystal spectrometer makes use of high light gathering power and high orders of reflection to allow high resolution studies of weak spectral lines. It also has the advantage of ease of alignment and operation.
The Pain Catastrophizing Scale (PCS) measures three aspects of catastrophic cognitions about pain—rumination, magnification, and helplessness. To facilitate assessment and clinical application, we aimed to (a) develop a short version on the basis of its factorial structure and the items’ correlations with key pain-related outcomes, and (b) identify the threshold on the short form indicative of risk for depression.
Social centers for older people.
664 Chinese older adults with chronic pain.
Besides the PCS, pain intensity, pain disability, and depressive symptoms were assessed.
For the full scale, confirmatory factor analysis showed that the hypothesized 3-factor model fit the data moderately well. On the basis of the factor loadings, two items were selected from each of the three dimensions. An additional item significantly associated with pain disability and depressive symptoms, over and above these six items, was identified through regression analyses. A short-PCS composed of seven items was formed, which correlated at r=0.97 with the full scale. Subsequently, receiver operating characteristic (ROC) curves were plotted against clinically significant depressive symptoms, defined as a score of ≥12 on a 10-item version of the Center for Epidemiologic Studies-Depression Scale. This analysis showed a score of ≥7 to be the optimal cutoff for the short-PCS, with sensitivity = 81.6% and specificity = 78.3% when predicting clinically significant depressive symptoms.
The short-PCS may be used in lieu of the full scale and as a brief screen to identify individuals with serious catastrophizing.
Rabies is one of the major public health problems in China, and the mortality rate of rabies remains the highest among all notifiable infectious diseases. A meta-analysis was conducted to investigate the post-exposure prophylaxis (PEP) vaccination rate and risk factors for human rabies in mainland China. The PubMed, Web of Science, Chinese National Knowledge Infrastructure, Chinese Science and Technology Periodical and Wanfang databases were searched for articles on rabies vaccination status (published between 2007 and 2017). In total, 10 174 human rabies cases from 136 studies were included in this meta-analysis. Approximately 97.2% (95% confidence interval (CI) 95.1–98.7%) of rabies cases occurred in rural areas and 72.6% (95% CI 70.0–75.1%) occurred in farmers. Overall, the vaccination rate in the reported human rabies cases was 15.4% (95% CI 13.7–17.4%). However, among vaccinated individuals, 85.5% (95% CI 79.8%–83.4%) did not complete the vaccination regimen. In a subgroup analysis, the PEP vaccination rate in the eastern region (18.8%, 95% CI 15.9–22.1%) was higher than that in the western region (13.3%, 95% CI 11.1–15.8%) and this rate decreased after 2007. Approximately 68.9% (95% CI 63.6–73.8%) of rabies cases experienced category-III exposures, but their PEP vaccination rate was 27.0% (95% CI 14.4–44.9%) and only 6.1% (95% CI 4.4–8.4%) received rabies immunoglobulin. Together, these results suggested that the PEP vaccination rate among human rabies cases was low in mainland China. Therefore, standardised treatment and vaccination programs of dog bites need to be further strengthened, particularly in rural areas.
Vegetable and grain amaranths represent a vital source of micronutrients and protein in Asia and Africa. However, various foliar lepidopteran pests and stem-mining weevils hinder amaranth production. Insect-resistant cultivars can enhance the productivity of this crop. Here, we report on the performances of amaranth varieties screened for their resistance to insect pests under the field conditions at The World Vegetable Center stations in Asia and sub-Saharan Africa. We conducted two preliminary screening trials with a total of 263 entries from around the world in Taiwan and a third preliminary screening trial with 49 African-indigenous entries in Tanzania. Promising entries from these preliminary trials were collectively evaluated in an advanced screening trial in Tanzania, to identify lines resistant to foliar and stem-boring pests in East Africa. Four entries exhibited moderate resistance to foliar pests: TZ51 and TZ53 (Amaranthus cruentus), TZ34 (A. dubius) and TZ39 (Amaranthus sp.). Five entries showed moderate resistance to stem weevils: TZ06 and TZ27 (A. cruentus), TZ52 (A. graecizans), TZ59 (A. palmeri) and TZ07 (Amaranthus sp.). Lepidopteran pests affecting leaves were reared to adulthood and identified as Spoladea recurvalis (Crambidae), Spodoptera exigua (Noctuidae) and Spodoptera littoralis (Noctuidae). Stem weevil larvae were also reared and identified as: Neocleonus sannio Herbst, Gasteroclisus pr. rhomboidalis Boheman, Hypolixus pr. haerens Boheman and Baradine sp. (Curculionidae). These results highlight key amaranth pests in East Africa and identify insect-resistant entries that will be useful in breeding programmes and resistance studies.
Using time-resolved laser-scanning confocal microscopy and ultrafast optical pump/THz probe spectroscopy, we measure photoluminescence (PL) and THz-conductivity in perovskite micro-crystals and films. PL quenching and lifetime variations occur from local heterogeneity. Ultrafast THz-spectra measure sharp quantum transitions from excitonic Rydberg states, providing weakly bound excitons with a binding energy of ~13.5 meV at low temperatures. Ab-initio electronic structure calculations give a direct band gap of 1.64 eV, a dielectric constant of ~18, heavy electrons, and light holes, resulting in weakly bound excitons, consistent with the binding energies from the experiment. The complementary spectroscopy and simulations reveal fundamental insights into perovskite light-matter interactions.
Recent researches have showed that probiotics promote bone health in humans and rodents. The objective of this study was to determine if probiotics have the similar effects in laying hens. Ninety-six 60-week-old White Leghorn hens were assigned to four-hen cages based on their BW. The cages were randomly assigned to 1 of 4 treatments: a layer diet mixed with a commercial probiotic product (containing Enterococcus faecium, Pediococcus acidilactici, Bifidobacterium animalis and Lactobacillus reuteri) at 0, 0.5, 1.0 or 2.0 g/kg feed (Control, 0.5×, 1.0× and 2.0×) for 7 weeks. Cecal Bifidobacterium spp. counts were higher in all probiotic groups (P<0.001) compared with the control group. The percentage of unmarketable eggs (cracked and shell-less eggs) was decreased in both 0.5× and 2.0× groups compared with the control group (P=0.02), mainly due to the reduction of shell-less eggs (P=0.05). The increases in tibial and femoral mineral density and femoral mineral content (P=0.04, 0.03 and 0.02, respectively), with a concomitant trend of increases in humerus mineral density and tibial mineral content (P=0.07 and 0.08, respectively), occurred in the 2.0× group. However, the bone remodeling indicators of circulating osteocalcin and c-terminal telopeptide of type I collagen were similar among all groups (P>0.05). In addition, the plasma concentrations of cytokines (interleukin-1β, interleukin-6, interleukin-10, interferon-γ and tumor necrosis factor-α) and corticosterone as well as the levels of heterophil to lymphocyte ratio were similar between the 2.0× group and the control group (P>0.05). In line with these findings, no differences of cecal tonsil mRNA expressions of interleukin-1β, interleukin-6 and lipopolysaccharide-induced tumor necrosis factor-α factor were detected between these two groups (P>0.05). These results suggest that immune cytokines and corticosterone may not involve in the probiotic-induced improvement of eggshell quality and bone mineralization in laying hens. In conclusion, the dietary probiotic supplementation altered cecal microbiota composition, resulting in reduced shell-less egg production and improved bone mineralization in laying hens; and the dietary dose of the probiotic up to 2.0× did not cause negative stress reactions in laying hens.
Introduction: Survival from cardiac arrest has been linked to the quality of resuscitation care. Unfortunately, healthcare providers frequently underperform in these critical scenarios, with a well-documented deterioration in skills weeks to months following advanced life support courses. Improving initial training and preventing decay in knowledge and skills are a priority in resuscitation education. The spacing effect has repeatedly been shown to have an impact on learning and retention. Despite its potential advantages, the spacing effect has seldom been applied to organized education training or complex motor skill learning where it has the potential to make a significant impact. The purpose of this study was to determine if a resuscitation course taught in a spaced format compared to the usual massed instruction results in improved retention of procedural skills. Methods: EMS providers (Paramedics and Emergency Medical Technicians (EMT)) were block randomized to receive a Pediatric Advanced Life Support (PALS) course in either a spaced format (four 210-minute weekly sessions) or a massed format (two sequential 7-hour days). Blinded observers used expert-developed 4-point global rating scales to assess video recordings of each learner performing various resuscitation skills before, after and 3-months following course completion. Primary outcomes were performance on infant bag-valve-mask ventilation (BVMV), intraosseous (IO) insertion, infant intubation, infant and adult chest compressions. Results: Forty-eight of 50 participants completed the study protocol (26 spaced and 22 massed). There was no significant difference between the two groups on testing before and immediately after the course. 3-months following course completion participants in the spaced cohort scored higher overall for BVMV (2.2 ± 0.13 versus 1.8 ± 0.14, p=0.012) without statistically significant difference in scores for IO insertion (3.0 ± 0.13 versus 2.7± 0.13, p= 0.052), intubation (2.7± 0.13 versus 2.5 ± 0.14, p=0.249), infant compressions (2.5± 0.28 versus 2.5± 0.31, p=0.831) and adult compressions (2.3± 0.24 versus 2.2± 0.26, p=0.728) Conclusion: Procedural skills taught in a spaced format result in at least as good learning as the traditional massed format; more complex skills taught in a spaced format may result in better long term retention when compared to traditional massed training as there was a clear difference in BVMV and trend toward a difference in IO insertion.
Achieving adequate fertility is essential in any dairy unit, but is compromised by genetic selection for increased yield. Selection has altered the somatotrophic axis and resulted in cows which mobilise more body tissue for milk production in early lactation, thus prolonging both the depth and duration of the post partum negative energy balance. Poor energy status is reflected in altered metabolic parameters including raised urea and decreased insulin-like growth factor-I (IGF-I) and insulin concentrations, which adversely affect ovarian cyclicity and early embryo survival. Attempts to optimise the diet in terms of energy and protein content have generally been aimed at increasing milk production further rather than improving fertility. Advances in biosensor technology now provide us with the opportunity to monitor production, fertility and health parameters of each cow. Integration of this information should improve the timing for inseminations and could assist in selecting diets more suited to the needs of the individual cow. Genetic selection may in future be used to produce cows optimised for a particular type of management system. In both cases we need a greater understanding of the rules governing nutrient partitioning at different stages of the cows' life cycle to ensure that diets selected are cost effective and achieve an appropriate balance in promoting production, reproduction and health.
We have obtained FUSE spectra of several dwarf novae which reveal the properties of their accreting white dwarfs, their rates of accretion during quiescence and the nature of their boundary layer/inner disk regions including accretion belts on the white dwarfs. Among the systems for which preliminary results will be presented are BV Cen, WW Ceti, EY Cyg, SS Aur and VW Hyi. The contribution of these FUSE studies to our understanding of disk accretion physics will be emphasized within the context of the white dwarf and boundary layer.
For 2D elastic-plastic flows with the hypo-elastic constitutive model and von Mises’ yielding condition, the non-conservative character of the hypo-elastic constitutive model and the von Mises’ yielding condition make the construction of the solution to the Riemann problem a challenging task. In this paper, we first analyze the wave structure of the Riemann problem and develop accordingly a Four-Rarefaction wave approximate Riemann Solver with Elastic waves (FRRSE). In the construction of FRRSE one needs to use an iterative method. A direct iteration procedure for four variables is complex and computationally expensive. In order to simplify the solution procedure we develop an iteration based on two nested iterations upon two variables, and our iteration method is simple in implementation and efficient. Based on FRRSE as a building block, we propose a 2nd-order cell-centered Lagrangian numerical scheme. Numerical results with smooth solutions show that the scheme is of second-order accuracy. Moreover, a number of numerical experiments with shock and rarefaction waves demonstrate the scheme is essentially non-oscillatory and appears to be convergent. For shock waves the present scheme has comparable accuracy to that of the scheme developed by Maire et al., while it is more accurate in resolving rarefaction waves.
Bacillary dysentery continues to be a major health issue in developing countries and ambient temperature is a possible environmental determinant. However, evidence about the risk of bacillary dysentery attributable to ambient temperature under climate change scenarios is scarce. We examined the attributable fraction (AF) of temperature-related bacillary dysentery in urban and rural Hefei, China during 2006–2012 and projected its shifting pattern under climate change scenarios using a distributed lag non-linear model. The risk of bacillary dysentery increased with the temperature rise above a threshold (18·4 °C), and the temperature effects appeared to be acute. The proportion of bacillary dysentery attributable to hot temperatures was 18·74% (95 empirical confidence interval (eCI): 8·36–27·44%). Apparent difference of AF was observed between urban and rural areas, with AF varying from 26·87% (95% eCI 16·21–36·68%) in urban area to −1·90% (95 eCI −25·03 to 16·05%) in rural area. Under the climate change scenarios alone (1–4 °C rise), the AF from extreme hot temperatures (>31·2 °C) would rise greatly accompanied by the relatively stable AF from moderate hot temperatures (18·4–31·2 °C). If climate change proceeds, urban area may be more likely to suffer from rapidly increasing burden of disease from extreme hot temperatures in the absence of effective mitigation and adaptation strategies.
Fosfomycin has become a therapeutic option in urinary tract infections. We identified 57 fosfomycin-resistant Escherichia coli from 465 urine-derived extended-spectrum β-lactamase (ESBL)-producing isolates from a Chinese hospital during 2010–2014. Of the 57 fosfomycin-resistant isolates, 51 (89·5%) carried fosA3, and one carried fosA1. Divergent pulsed-field gel electrophoresis profiles and multi-locus sequence typing results revealed high clonal diversity in the fosA3-positive isolates. Conjugation experiments showed that the fosA3 genes from 50 isolates were transferable, with IncFII or IncI1 being the most prevalent types of plasmids. The high prevalence of fosA3 was closely associated with that of blaCTX-M. Horizontal transfer, rather than clonal expansion, might play a central role in dissemination. Such strains may constitute an important reservoir of fosA3 and blaCTX-M, which may well be readily disseminated to other potential human pathogens. Since most ESBL-producing E. coli have acquired resistance to fluoroquinolones worldwide, further spread of fosA3 in such E. coli isolates should be monitored closely.
To study the association between gastrointestinal colonization of carbapenemase-producing Enterobacteriaceae (CPE) and proton pump inhibitors (PPIs).
We analyzed 31,526 patients with prospective collection of fecal specimens for CPE screening: upon admission (targeted screening) and during hospitalization (opportunistic screening, safety net screening, and extensive contact tracing), in our healthcare network with 3,200 beds from July 1, 2011, through December 31, 2015. Specimens were collected at least once weekly during hospitalization for CPE carriers and subjected to broth enrichment culture and multiplex polymerase chain reaction.
Of 66,672 fecal specimens collected, 345 specimens (0.5%) from 100 patients (0.3%) had CPE. The number and prevalence (per 100,000 patient-days) of CPE increased from 2 (0.3) in 2012 to 63 (8.0) in 2015 (P<.001). Male sex (odds ratio, 1.91 [95% CI, 1.15–3.18], P=.013), presence of wound or drain (3.12 [1.70–5.71], P<.001), and use of cephalosporins (3.06 [1.42–6.59], P=.004), carbapenems (2.21 [1.10–4.48], P=.027), and PPIs (2.84 [1.72–4.71], P<.001) in the preceding 6 months were significant risk factors by multivariable analysis. Of 79 patients with serial fecal specimens, spontaneous clearance of CPE was noted in 57 (72.2%), with a median (range) of 30 (3–411) days. Comparing patients without use of antibiotics and PPIs, consumption of both antibiotics and PPIs after CPE identification was associated with later clearance of CPE (hazard ratio, 0.35 [95% CI, 0.17–0.73], P=.005).
Concomitant use of antibiotics and PPIs prolonged duration of gastrointestinal colonization by CPE.
The isotopic composition of ancient wood has the potential to provide information about past environments. We analyzed the δ13C, δ18O, and δ2H of cellulose of conifer trees from several cross-sections at each of 9 sites around the Great Lakes region ranging from ∼4000 to 14,000 cal BP. Isotopic values of Picea, Pinus, and Thuja species seem interchangeable for δ18O and δ2H comparisons, but Thuja appears distinctly different from the other 2 in its δ13C composition. Isotopic results suggest that the 2 sites of near-Younger Dryas age experienced the coldest conditions, although the Gribben Basin site near the Laurentide ice sheet was relatively dry, whereas the Liverpool site 500 km south was moister. The spatial isotopic variability of 3 of the 4 sites of Two Creeks age shows evidence of an elevation effect, perhaps related to sites farther inland from the Lake Michigan shoreline experiencing warmer daytime growing season temperatures. Thus, despite floristic similarity across sites (wood samples at 7 of the sites being Picea), the isotopes appear to reflect environmental differences that might not be readily evident from a purely floristic interpretation of macrofossil or pollen identification.
High-resolution radiocarbon calibration for the last 14,000 cal yr has been developed in large part using European oaks and pines. Recent subfossil wood collections from the Great Lakes region provide an opportunity to measure 14C activity in decadal series of rings in North America prior to the White Mountains bristlecone record. We developed decadal 14C series from wood at the classic Two Creeks site (∼11,850 BP) in east-central Wisconsin, the Liverpool East site (∼10,250 BP) in northwestern Indiana, and the Gribben Basin site (∼10,000 BP) in the Upper Peninsula of Michigan. Initial AMS dates on holocellulose produced younger-than-expected ages for most Two Creeks subsamples and for a few samples from the other sites, prompting a systematic comparison of chemical pretreatment using 2 samples from each site, and employing holocellulose, AAA-treated holocellulose, alpha-cellulose, and AAA-treated whole wood. The testing could not definitively reveal the source of error in the original analyses, but the “best” original ages together with new AAA-treated holocellulose and α-cellulose ages were visually fitted to the IntCal04 calibration curve at ages of 13,760–13,530 cal BP for the Two Creeks wood, 12,100–12,020 cal BP for Liverpool East, and 11,300–11,170 cal BP for Gribben Basin. The Liverpool East age falls squarely within the Younger Dryas (YD) period, whereas the Gribben Basin age appears to postdate the YD by ∼300 yr, although high scatter in the decadal Gribben Basin results could accommodate an older age nearer the end of the YD.
Deep-sea corals are a promising new archive of paleoclimate. Coupled radiocarbon and U-series dates allow 14C to be used as a tracer of ocean circulation rate in the same manner as it is used in the modern ocean. Diagenetic alteration of coral skeletons on the seafloor requires a thorough cleaning of contaminating phases of carbon. In addition, 10% of the coral must be chemically leached prior to dissolution to remove adsorbed modern CO2. A survey of modern samples from the full δ14C gradient in the deep ocean demonstrates that the coralline CaCO3 records the radiocarbon value of the dissolved inorganic carbon.