bluuebunny/crossref_metadata_2025_split huggingface dataset:
Outbreak of Hepatitis C Virus Infection in a Hemodialysis Unit: Potential Transmission by the Hemodialysis Machine?
Authors: Delarocque-Astagneau Elisabeth , Baffoy Nadège , Thiers Valérie , Simon Nicole , Valk Henriette de , Laperche Syria , Couroucé Anne-Marie , Astagneau Pascal , Buisson Claude , Desenclos Jean-Claude 
Published: May 2019

Objective:To identify the routes of transmission during an outbreak of infection with hepatitis C virus (HCV) genotype 2a/2c in a hemodialysis unit.Design:A matched case-control study was conducted to identify risk factors for HCV seroconversion. Direct observation and staff interviews were conducted to assess infection control practices. Molecular methods were used in a comparison of HCV infecting isolates from the case-patients and from patients infected with the 2a/2c genotype before admission to the unit.Setting:A hemodialysis unit treating an average of 90 patients.Patients:A case-patient was defined as a patient receiving hemodialysis with a seroconversion for HCV genotype 2a/2c between January 1994 and July 1997 who had received dialysis in the unit during the 3 months before the onset of disease. For each case-patient, 3 control-patients were randomly selected among all susceptible patients treated in the unit during the presumed contamination period of the case-patient.Results:HCV seroconversion was associated with the number of hemodialysis sessions undergone on a machine shared with (odds ratio [OR] per additional session, 1.3; 95% confidence interval [CI95], 0.9 to 1.8) or in the same room as (OR per additional session, 1.1; CI95, 1.0 to 1.2) a patient who was anti-HCV (genotype 2a/2c) positive. We observed several breaches in infection control procedures. Wetting of transducer protectors in the external pressure tubing sets with patient blood reflux was observed, leading to a potential contamination by blood of the pressure-sensing port of the machine, which is not accessible to routine disinfection. The molecular analysis of HCV infecting isolates identified among the case-patients revealed two groups of identical isolates similar to those of two patients infected before admission to the unit.Conclusions:The results suggest patient-to-patient transmission of HCV by breaches in infection control practices and possible contamination of the machine. No additional cases have occurred since the reinforcement of infection control procedures and the use of a second transducer protector.
High genetic merit and high-producing dairy cows in commercial Australian herds don't have substantially worse reproductive performance
Authors: Morton J.M. 
Published: May 2019

AbstractThe National Dairy Herd Fertility Project (renamed the InCalf Project) consists of two large, prospective observational studies conducted in commercial dairy herds from 4 Australian states. The project aims to identify factors associated with variation in reproductive performance between cows and herds. The larger of the two studies included over 33,000 cows and 168 herds. The database has undergone extensive error checking and correction resulting in high quality data. Large variations in reproductive performance were observed between cows and herds, indicating that there are important risk factors for reproductive performance and that cows and herds are exposed to varying combinations of these risk factors. Models for several reproductive outcomes were constructed using multivariable stepwise logistic regression. No significant associations were detected between any measures of cow genetic merit and 6 week in-calf rate. Neither milk volume nor protein yield were significantly associated with 6 week in-calf rate. A weak negative association was detected between fat yield in the first 120 days of lactation and 6 week in-calf rate. However, differences in estimated 6-week in-calf rate between moderate and high producing groups (2 to 5 percentage points) were small when contrasted against the 63 percentage point range in performance observed between herds (23% to 86%).
The effect of crude protein and fermentable carbohydrate intake on blood metabolite concentrations and fertility in beef heifers
Authors: Kenny D.A. , Boland M.P. , Diskin M.G. , Sreenan J.M. 
Published: May 2019

AbstractHigh intakes of crude protein (CP), in particular rumen degradable protein (RDP), have been associated with reduced fertility in cattle. This reduction in fertility has been attributed to putative toxic effects of elevated systemic concentrations of ammonia and, or urea, the by-products of protein metabolism, on gametes and embryos. The objective of the studies reported here was to examine the effect of CP and fermentable carbohydrate intake on various blood metabolites and on fertility, in beef heifers. In the first experiment, 40 heifers were randomly assigned to either low (no urea) or high (240 g urea) RDP, grass silage based diets, supplemented with 1.5 or 3.0 kg dry matter (DM) of either rolled barley (BAR) or molassed sugar beet pulp (MSBP) or no carbohydrate (control). The high RDP diet increased plasma ammonia and urea concentrations. MSBP at 3 kg DM/day was more effective than BAR in reducing ammonia (P<0.05) and urea (P<0.001). In animals fed no urea, MSBP at 3 kg DM/day was also more effective than BAR in reducing systemic ammonia (P<0.001) and urea (P < 0.05). In the second experiment, 83 beef cross-bred heifers were randomly assigned over two replicates to one of 4 treatment groups in a 2 x 2 factorial design. Animals consuming high (85 kg N/ha; HN) or low (0 kg N/ha; LN) nitrogen fertilised pastures were supplemented with either 0 or 3 kg dry matter (DM) MSBP daily as follows: 1) HN only (n=21); 2) HN + 3kg MSBP, (n=22); 3) LN only (n=21); 4) LN + 3kg MSBP (n=19). The HN pastures had higher (P<0.001) CP and lower (P<0.001) water soluble carbohydrate concentrations than LN pastures. Systemic ammonia (P<0.05) and urea (P<0.001) were higher in heifers on the HN pasture. Embryo survival rate was high overall (80%) and was not affected by systemic ammonia or urea concentrations or by supplementation with MSBP. Systemic progesterone, insulin and glucose were not affected by treatment. High CP intake coupled with low fermentable carbohydrate, lead to elevated systemic ammonia and urea concentrations in heifers. However, no adverse effect on fertility was observed.
The effect of a copper, cobalt and selenium bolus on fertility and trace element status of dairy cattle.
Authors: Mackenzie A.M. , Moeini M.M , Telfer S.B. 
Published: May 2019

AbstractInfertility is one of the manifestations of clinical copper deficiency in dairy cattle that results from high dietary molybdenum intakes. This trial investigated the effects of slow release glass copper, cobalt and selenium boluses (Cosecure) on the number of inseminations required for confirmed pregnancy, calving interval and trace element status in dairy cattle. Sixty Holstein Friesian dairy cattle were allocated to one of two treatment groups, 30 cattle were treated with two soluble glass trace element boluses (Cosecure®,Telsol Ltd.) on day 0 and 169 while the remaining 30 cattle were left untreated (Controls). The cattle were grazed at pasture (day 0 to 165) which has been shown to contain high levels of molybdenum (range from 2.3 to 3.1 mg/kg DM). Blood samples were taken between days 0 and 280 to measure copper and selenium status and the number of inseminations and calving intervals were recorded. The control cattle required significantly more inseminations to confirmed pregnancy compared with the Cosecure treated cattle (2.5 v 1.7 SEmean 0.16, p<0.01) and had a significantly longer calving interval (397 v 372 days, SEmean 9.2, p<0.05). Plasma copper concentrations were significantly higher in the Cosecure treated cattle on days 30, 78 and 135 (p<0.01) compared with the controls, although the controls were all in the normal range (> 12 μmol/l). Cosecure treated cattle had significantly higher glutathione peroxidase (GSHPx) activities on day 246 (P.0.05). However, on all sample dates, the GSHPx activities were in the normal range for both treatment groups (>40units/ml PCV). The dietary cobalt intakes of the cows were measured (1.5 to 2.1 mg/kg DM in grass and 2.1 to 2.7 mg/Kg DM in compound) and found to be well in excess of the requirement of 0.2 mg/Kg DM. It was concluded that treatment with slow release glass copper, cobalt and selenium boluses (Cosecure) reduced the number of inseminations required for conception in the dairy cows due to the slowly released copper.
Relationship between genetic merit, milk production, body condition, blood parameters and reproductive performance of dairy cows
Authors: Snijders S.E.M. , Dillon P.G. , O'Farrell K.J. , Diskin M. , O'Callaghan D. , Rath M. , Boland M.P. 
Published: May 2019

AbstractBased on their pedigree indices for milk production traits, 48 high (HM) and 48 medium (MM) genetic merit cows were studied in each of two years to determine the possible relationships between genetic merit, milk production, body condition, metabolite and hormone concentrations, feed intake and reproductive performance. The high genetic merit cows had higher milk production, greater body condition loss between calving and first service, lower plasma glucose and insulin-like growth factor-1 (IGF-1) and lower first and second service conception rates than the medium genetic merit cows. Furthermore, more high genetic merit cows were not pregnant at the end of the breeding period compared with medium genetic merit cows. Cows that did not conceive to first service were retrospectively compared to those that conceived to first service within each genetic merit category. Within the high and medium genetic merit category there were no significant differences between the cows that did not conceive and those that conceived to first service in terms of milk production, or plasma concentrations of glucose, non-esterified fatty acids (NEFA). Although medium genetic merit cows that did not conceive to first service lost more body condition score between calving and first service than those that conceived to first service, there was no difference in body condition score (BCS) change between calving and first service between high genetic merit cows that did not conceive and those that conceived to first service. In the present study, high genetic merit cows had higher milk production and reduced reproductive performance in comparison with medium genetic merit cows. However, reproductive performance was not associated with milk production, energy balance or plasma concentrations of glucose, NEFA or IGF-1 between calving and insemination
Economic Incentives and Resource Allocation in U.S. Public and Private Plant Breeding
Authors: Fuglie Keith O. , Walker Thomas S. 
Published: May 2019

AbstractPrivate investment in plant breeding has been increasing while public plant breeding has stagnated or declined. Moreover, research investment among crop commodities is uneven. Using a comprehensive survey of U.S. plant breeders from 1994, we use a simultaneous equations model to examine incentives and public-private tradeoffs in plant breeding research among 84 crop commodities. Allocation of private breeders among crops is strongly influenced by market size, hybrid seed technology, and ease of breeding improvement. In general, the allocation of public breeders does not appear to “crowd out” private breeders, but some competition may occur in applied breeding. Public breeding declines as private breeding increases on a commodity. Public breeding is also affected by market size, ease of breeding improvement, and political influence.
Genetic and nutritional effects on lactational performance of gilts selected for components of efficient lean growth
Authors: Cameron N.D. , Kerr J.C. , Garth G.B. , Fenty R. , Peacock A. 
Published: May 2019

AbstractLactational performance was measured in Large White gilts from lines that had been divergently selected over seven generations for daily food intake (DFI), lean food conversion ratio (LFC), lean growth rate with ad-libitum (LGA) or restricted (LGS) feeding during performance test. Control line gilts were included in the study. During the lactation period of 21 days, gilts were given to appetite five isoenergetic diets differing in ileal digestible lysine: energy (0·40, 0·58, 0·76, 0·94 and 1·12 g/MJ digestible energy). The study consisted of 223 gilts with a similar number of animals in each selection line.Live-weight loss was greater in the low LFC and LGA lines than in the high lines and food intake was significantly lower in the low LGA line than in the high line. Litter-weight gain of the low LFC and high LGA lines were greater than in the complementary selection lines. Prediction equations for nutrient utilization were used to express the effect of diet and selection line in terms of energy and protein inputs and outputs. Selection on DFI or LGS resulted in gilts that did not mobilize lipid during lactation as sufficient energy for milk and maintenance was provided by dietary intake. In contrast, there was insufficient dietary energy with selection on LFC or on low LGA so lipid mobilization was required to achieve energy balance. The energy required to excrete excess protein and energy from lipid mobilization increased as the dietary lysine energy ratio increased, but there were no other dietary effects on energy and protein utilization. Genotype with nutrition interactions were detected for energy intake and lipid mobilization, which were due to the lines selected for low DFI and LGA. The general absence of genotype with nutrition interactions for lactational performance in gilts selected for components of efficient lean growth and the lack of significant dietary effects on energy utilization indicated that the consequences of changing nutritional inputs will be broadly similar for genotypes within the set of genotypes studied. Selection strategies which result in reduced food intake during lactation should be avoided if lipid mobilization is then required to attain energy balance and there are resultant negative effects on subsequent reproductive performance.
Endocrine changes and their relationship with body weight in growing yaks
Authors: Yongqiang Tian , Xingxu Zhao , Minqiang Wang , Zhonglin Lu , Rongchang Zhang 
Published: May 2019

AbstractThe concentrations of growth hormone (GH), insulin (Ins), tri-iodothyronine (T3) and thyroxine (T4) in blood samples of growing yaks during different bimonthly seasons were determined by radioimmunoassay. The changes of body weight of growing yaks and composition of grass grazed were measured accordingly. The seasonal changes of hormones were significant (P < 0·01 or P < 0·05). Within season, the variances of hormones depended upon the different growing stages. The body-weight gains in the different groups varied in different seasons, increase being significant in May, July and September, decrease being significant from January to May. Correlation analysis indicated that T4 concentration had a significant positive correlation with the body weight of the growing yaks(r = 0·2509, P < 0·05) and other hormones did not have any significant correlation with body weight. The results showed that the annual cycle of weight loss and gain was attributed to the seasonal change of nutrition status. The seasonal change of the assayed hormones depended on the grass growth.
The effect of a neighbouring conspecificversusthe use of a mirror for the control of stereotypic weaving behaviour in the stabled horse
Authors: Mills D.S. , Davenport K. 
Published: May 2019

AbstractWeaving behaviour involves the repetitive lateral swaying of the head, neck, forequarters and sometimes hindquarters of the horse and is generally believed to be indicative of poor welfare. The behaviour of six known weavers was recorded three times a day for 5 days in each of three different stable designs. These were a conventional loose-box, a conventional loose-box with a 1 m2 acrylic mirror and a conventional loose-box in which there was a grilled 1 m2 side window separating the resident horse from a non-weaving conspecific in an adjacent stable. Weaving and other stereotypic behaviours were significantly higher in the unmodified stable and during the late afternoon observation period. There was no significant difference in the amount of stereotypic behaviour recorded in the two modified stables. Significant differences in the behaviour patterns and location of horses during the study suggest that activity engaging with either a visual image of a horse or a hay net is associated with a reduction in weaving and other repetitive activities in the stabled horse.
Plasma concentrations of cortisol and progesterone during the period of reproductive development in beef and dairy heifers
Authors: Rawlings N. C. , Kastelic J. P. , Evans A.C. O. , Bartlewski P. M. , Beard A. P. , Chandolia R. K. , Cook S. J. 
Published: May 2019

AbstractThe plasma concentrations of cortisol and progesterone during reproductive maturation in the heifer calf were examined. Six beef heifer calves were handled and bled every 2 weeks (control), 30 were left unhandled (naive). At 13, 21, 30, 39 and 47 weeks of age, a different group of naive heifers and the control heifers were bled every day for 5 days (puberty seen at 57·4 (s.e. 1·3) weeks). Thirty-nine dairy heifer calves were allocated to seven groups to receive adrenocorticotropic hormone (ACTH) at either 4, 7, 9, 16, 26, 36 or 46 weeks of age (puberty expected around 43 weeks of age). Plasma concentrations of cortisol increased at 21, 30 and 39 weeks of age in frequently handled and naive beef heifers; the increase was greater at these ages in the naive beef heifers (age and treatment P < 0·01). No age trend was apparent for plasma concentrations of cortisol and progesterone prior to ACTH injections (t = 0) in frequently handled dairy heifers. Adrenal progesterone secretion did not change with age in beef heifers, but naive beef heifers had greater plasma concentrations than frequently handled beef heifers. ACTH induced cortisol release in dairy heifers as early as 4 weeks of age (P < 0·05), but the response was greater in dairy heifers 16 weeks old and older (P < 0·05). A progesterone response to ACTH in dairy heifers was not seen until animals were 9 weeks old. It is concluded that as heifers mature reproductively, there is a parallel increase in the sensitivity of the adrenal gland to ACTH and handling stress.
Wave motion in a conducting fluid with a layer adjacent to the boundary, II. Eigenfunction expansions
Authors: Smith William V. 
Published: May 2019

AbstractThe wave motion of magnetohydrodynamic (MHD) systems can be quite complicated. In order to study the motion of waves in a perfectly conducting fluid under the influence of an external magnetic field in a stratified medium, we make the simplifying assumption that the pressure is constant (to first order). This is the simplest form of the equations with variable coefficients and is not strongly propagative. Alfven waves are still present. The system is further simplified by assuming that the external field is parallel to the boundary. The Green's function for the operator is constructed and then the spectral family is constructed in terms of generalized eigenfunctions, giving four families of propagating waves, including waves “trapped” in the boundary layer. These trapped waves are interesting, since they are not the relics of surface waves, which do not exist in this context when the boundary layer shrinks to zero thickness no matter what (maximal energy preserving) boundary condition is chosen. We conjecture a similar structure for the full MHD problem.
Validity Evidence of the Retirement Resources Inventory
Authors: Amorim Silvia Miranda , França Lucia Helena de Freitas Pinho 
Published: May 2019

AbstractThe current populational aging context requires that society reflect on the variables related with well-being and discuss ways of how to ensure them. The Conservation of Resources Theory (Hobfoll, 1989, 2002) posits that individuals who possess more material or social resources are more capable of resolving conflicts and dealing with stressful situations, thus maintaining good levels of well-being. However, there is a lack of instruments aimed at measuring the necessary resources for retirement well-being. The objective of this study was to translate and analyse the psychometric qualities of the Retirement Resources Inventory (RRI) (Leung & Earl, 2012) as applied to 1002 Brazilian retirees. Exploratory and confirmatory factor analysis were undertaken using two independent subsamples consisting of 401 and 601 retirees respectively. Two viable models arose from the exploratory analysis: A five-factor model, χ2(gl) = 816.644 (271); CFI = 0.88; GFI = 0.98; RMSEA = 0.07; R2 = 0.55; and a six-factor model, χ2(gl) = 1028.291 (400); CFI = 0.88; GFI = 0.98; RMSEA = 0.03; R2= 0.53, with good fit indices, but similar to each other. Confirmatory analysis pointed towards an instrument consisting of 29 items and five factors with good fit indices, χ2(gl) = 1,274(364); CFI = 0.87; TLI: 0.86; RMSEA: 0.06, corroborating the model proposed by Wang and Shultz (2010). The analyses also highlighted the need for actions that take into account the gender, age and region of the country where the retiree lives. Future cross-cultural studies are recommended seeing that retirement planning is an emerging issue that affects the world as a whole.
First Ground‐Based Conjugate Observations of Stable Auroral Red (SAR) Arcs
Authors: Martinis C. , Baumgardner J. , Mendillo M. , Taylor M.J. , Moffat‐Griffin T. , Wroten J. , Sullivan C. , Macinnis R. , Alford B. , Nishimura Y. 
Published: May 2019

AbstractDuring the geomagnetic storm of 1 June 2013, all‐sky imagers located at geomagnetically conjugate locations at Millstone Hill, USA (42.6°N, 71.4°W, 50.9° mag lat) and at Rothera, Antarctica (67.5°S, 68.1°W, ‐53.2° mag lat), allowed us to measure a stable auroral red (SAR) arc simultaneously in both hemispheres for the first time. The arc measured in one hemisphere was observed very close to its conjugate location in the opposite hemisphere. While spatial characteristics, such as equatorward motion and latitudinal extent, were similar at both sites, morphological properties, for example, arc brightness and shape of the poleward edges, differed. The overall brightness of the northern hemisphere arc was considerably weaker, by a factor of ~2‐3, throughout the night. Reduced magnetospheric forcing, in a short time interval between ~0345 UT and 0445 UT, led to decreased SAR arc brightness and reduced equatorward motion at both sites. A substorm occurring near 0500UT provided additional energization that increased the SAR arc brightness as well as the speed of the equatorward motion. These results provide evidence of a complex coupling between energy sources in the inner magnetosphere and the ionospheric receptor conditions within the subauroral domain at opposite ends of the same geomagnetic field line.