bluuebunny/crossref_metadata_2025_split huggingface dataset:
A genetic evaluation of growth in sheep using random regression techniques
Authors: Lewis R.M. , Brotherstone S. 
Published: May 2019

AbstractRepeated measures of live weight in growing animals are used to describe the path by which they travel from birth to maturity. A family of growth functions-the Gompertz is one in particular-has been used successfully to describe this journey with relatively few parameters (most importantly mature size and a rate parameter). However, using these functions to differentiate the genetic merit of individual animals to grow is problematic since the estimates of these parameters are highly correlated and are obtained with varying precision among animals. An alternative is random regression (RR) methodology. It allows environmental effects specific to the time of recording to be accounted for and can accommodate genetic differences in the shape of each animal’s growth curve. At present, though, only linear models (polynomials) can pragmatically be fitted with RR. This may be limiting since a priori beliefs about the appropriate form of a growth function, such as the non-linear Gompertz equation, cannot be accommodated. This paper describes the application of RR techniques to describe growth on a population of Suffolk sheep and compares the genetic evaluation predicted from a RR model with that obtained from a more traditional method based on a Gompertz form.The RR model chosen as providing the best fit (P < 0·01) included additive genetic and permanent environmental (between repeat records of an individual) effects fitted to a fifth order polynomial, and dam effects fitted to a third order polynomial. Measurement error was modelled as six classes. The heritability varied at different points along the growth trajectory (from 0·09 at 15 days to 0·33 at 150 days), suggesting that live weight early in a lamb’s life is a different trait to live weight later in life. There was genetic variation in the growth curves of individual animals, which was accounted for by fitting a RR model. Breeding values obtained by RR and a Gompertz approach were moderately to highly correlated (0·81 at 56 days, 0·91 at 150 days). If breeding value for live weight at 150 days of age were the selection criterion, similar individuals would be chosen with both methodologies. The ‘better’ properties and greater flexibility of the RR approach are discussed.
The response of growing pigs to amino acids as influenced by environmental temperature: tryptophan
Authors: Ferguson N.S. , Gous R.M. 
Published: May 2019

AbstractAn experiment was performed to measure the response of young pigs to dietary tryptophan (TRP) concentrations and environmental temperatures. Seventy-two entire male Large White ✕ Landrace pigs were assigned to one of six dietary treatments (2·90 (T1), 2·46 (T2), 2·01 (T3), 1·57 (T4), 1·12 (T5) g/kg and T5 + supplemented TRP (T6)) and one of three temperature treatments (20, 25 and 30°C) at a mean starting live weight of 14·38 (s.e. 0·201)kg. Animals were given ad libitum access to food until a final weight of 26·42 (s.e. 0·479) kg. There were no significant interactions between temperature and dietary TRP on any production variable. There was a significant (P < 0·05) quadratic improvement in the rate of live-weight growth (ADG) as the concentration of dietary TRP increased and as the temperature decreased. However, the response to increasing dietary TRP was independent of the environmental temperature. Maximum ADG was attained on T2 (0·498 (s.e. 0·023) kg/day) and at 20ºC (0·412 (s.e. 0·024) kg/day). Final live weight was a significant (P < 0·001) covariate for ADG and food intake (FI) responses. With TRP as a precursor for serotonin, a neurotransmitter that regulates appetite, it was anticipated that food intake would be affected with decreasing dietary TRP levels. However, there was no response in daily food intake to decreasing TRP concentration. This lack of response in appetite to dietary TRP may have been a result of an increasing TRP to large neutral amino acid ratio, which is known to correlate with an increase in serotonin synthesis. Total heat loss followed a similar response to FI. The gain per unit of food consumed was significantly (P < 0·001) reduced as the TRP content of the diet was decreased. The most efficient treatments were T1 (506 (s.e. 1·90) g gain per kg food) and T2 (495 (s.e. 23·2) g gain per kg food) while the worst was T5 (237 (s.e. 22·3) g gain per kg food). There were significant quadratic responses to dietary TRP in protein content of the empty body (P < 0·05) and the rate of protein retention (PR) (P < 001) but only PR was affected by temperature (P < 001). Both temperature (P < 0·05) and dietary TRP (P < 0·001) had a significant effect on the lipid content of the body but only temperature affected the rate of lipid retention, with a significantly (P < 0·001) lower rate at 30 oC. The efficiency of TRP utilization improved with increasing temperature. It was lowest at 20ºC (0·60 g TRP per kg protein) and highest at 30ºC (0·86 g/kg), while the mean efficiency for pigs between 14 and 26 kg live weight, at thermoneutrality (25°C), was close to 0·71 g/kg.
Weaning date affects calf growth rates and hind conception dates in farmed red deer (Cervus elaphus)
Authors: Pollard J.C. , Asher G.W. , Littlejohn R.P. 
Published: May 2019

AbstractTo determine how weaning date affected productivity in deer farming systems, calf growth rate, hind conception date, and hind condition were monitored on 10 New Zealand deer farms located in Otago and Southland, from February/March until August/September in 1999 (no. = 551 hind-calf pairs) and 2000 (no. = 414 pairs). On each farm, in both years, half of the hind-calf pairs were separated for early weaning (mean date 11 March; range 25 February to 17 March), while the other half remained together for late weaning (mean date 28 May; range 12 May to 10 June). Deer in both treatments on each farm were of similar age and genotype and stags were added to hind groups on the same day in March. Calves were weighed in February/March, May/June and August/September. Scanning of hinds to determine date of conception was carried out in June.Climatically the 2 years were very different with a summer drought preceding observations in 1999, nevertheless similar effects of weaning date were observed in both years. Calves weaned early gained less weight than the late-weaned calves (142 v. 210 g/day in 1999, and 131 v. 166 g/day in 2000) between February/March and May/June (P < 0·001). However mean conception dates were earlier in the early-weaned hinds compared with the late-weaned hinds (by 12 days in 1999 and 7 days in 2000,P < 0·001). Hind condition scores in May/June were higher for the early-weaned hinds compared with the late-weaned hinds (by 0·5 score units in 1999 and 0·3 score units in 2000, P < 0·001). For all measures the effects of weaning date varied between farms (P < 0·001). It was concluded that farmers weaning early could expect a positive effect on hind conception date and winter hind condition and a negative effect on calf growth rate, but management could override negative effects of weaning early or late.
Effect of nursing by two does on the performance of sucking and growing rabbits
Authors: Szendrö Zs. , Gyarmati T. , Maertens L. , Biró-Németh E. , Radnai I. , Milisits G. , Matics Zs. 
Published: May 2019

AbstractFive hundred and eighty-four Pannon White kits of 73 newborn litters were submitted to one of five treatments. Control litters (SS) were nursed once a day for 35 days post partum (traditional method of nursing). DD litters were raised by two does and the kits were nursed both in the morning and in the evening until day 35 post partum. DS litters were nursed twice a day for 23 days, and then once a day until weaning at 35 days. Part of the DS litters were nursed at 08:00 and 20:00 h (i.e. every 12 h, DS12), the rest were nursed at 08:00 and at 16:00 h (DS8). Kits of the fifth treatment (D0) were nursed twice a day until day 23, and then immediately weaned.Rabbit kits that were nursed twice a day (DD, DS12, DS8, D0) consumed on average 1·89 more milk compared with SS individuals until day 23 (overall treatment effect P < 0·001). The 21-day body weight of these young was 1·7 times greater than that of the SS kits (overall P < 0·001). D0 rabbits were weaned early and their growth curve showed a slight break at this point. However, they compensated for this lag by the end of the fattening period. SS rabbits and DD ones were respectively the first and the last to start consuming solid food. The food consumption of DS rabbits was similar to that of DD until day 23 and from then until day 35 it was not significantly different from that of SS. After having been weaned on day 23, D0 kits consumed only very small quantities of pellets for 2 days. Afterwards their food intake increased abruptly. Rabbits that were nursed twice a day (DD, DS12, DS8 and D0) consumed more food as compared with the SS individuals throughout the total period of fattening (157 v. 137 g/day; P < 0·05). The weight at 10 weeks of age was 2·49 v. 2·88 kg (overall P < 0·001), respectively for SS and doublenursed (DD, DS, D0) rabbits. Nursing twice a day did not affect dressing proportion but the proportion of the carcass in the front part of the body decreased slightly (318 v. 323 g/kg; P < 0·05) while that in intermediate part increased (321 v. 307 g/kg; P < 0·05). Nevertheless, rabbits that were nursed twice a day had more (P < 0·05) perirenal + scapular fat and produced heavier livers. Total fat content of the empty body, however, was not significantly higher, with the one exception of the DD rabbits which had higher levels than any other group. The results of our experiment show clearly that the growth potential of rabbit kits is strongly limited by the milk availability during the first weeks post partum.
Influence of level of maize cob meal on nutrient digestibility and nitrogen balance in Large White, Mukota and LW × M F1 crossbred pigs
Authors: Kanengoni A.T. , Dzama K. , Chimonyo M. , Kusina J. , Maswaure S.M. 
Published: May 2019

AbstractA study was conducted to compare the digestibility of organic matter (OM), neutral-detergent fibre (NDF), acid-detergent fibre (ADF), hemicellulose and nitrogen (N) and N balance in Mukota (M), Large White (LW) and the LW × M F1 pigs. Four male pigs of each breed, at proportionately 0·3 of their mature body weights, were randomly allocated to each of four diets in a cross-over design. The diets, which were formulated to contain similar levels of protein (ca. 160 g crude protein per kg) and energy (ca. 9 MJ metabolizable energy per kg), contained 0, 100, 200 and 300 g maize cob meal per kg, which corresponded to NDF levels of 276·4, 360·3, 402·9 and 523·5 g/kg dry matter, respectively. There was a negative correlation (P < 0·001) between the digestibility of OM, NDF, ADF and hemicellulose and the level of NDF in the diet. The digestibility of OM, NDF, ADF and hemicellulose decreased linearly (P < 0·05) with increase in the level of NDF among all three genotypes. There was a genotype × diet interaction on NDF and ADF digestibilities with digestibility in the LW decreasing faster (P < 0·05) than in the Mukota and LW × M F1 cross with increasing NDF. Both breed and level of maize cob meal affected N digestibility (P < 0·001), whilst the N retained per unit metabolic body weight was only affected by diet (P < 0·01). Increasing the level of maize cob meal beyond 100 g/kg, however, did not reduce N digestibility (P < 0·05). There was neither genotype nor dietary effect (P > 0·05) on N retained per unit N intake. These findings showed that the Mukota and the LW × M F1 cross were better able to digest the fibrous components than the LW. In addition, the Mukota and the LW × M F1 cross displayed an ability to retain protein to the same extent as the LW.
A dynamical systems model of the limiting oxygen index test
Authors: Nelson M. I. , Sidhu H. S. , Weber R. O. , Mercer G. N. 
Published: May 2019

AbstractOxygen index methods have been widely used to measure the flammability of polymeric materials and to investigate the effectiveness of fire-retardants. Using a dynamical systems framework we show how a limiting oxygen index can be identified with an appropriate bifurcation.The effectiveness of fire-retardants in changing the limiting oxygen index is calculated by unfolding the bifurcation point with a suitable non-dimensionalised variable, which depends upon the mode of action of the additive. In order to use this procedure it is essential the model is non-dimensionalised so as to retain the variables of interest as distinct continuation parameters.
Growth theorems for homogeneous second-order difference equations
Authors: Stević Stevo 
Published: May 2019

AbstractIn this paper we investigate the boundedness and asymptotic behaviour of the solutions of a class of homogeneous second-order difference equations with a single non-constant coefficient. These equations model, for example, the amplitude of oscillation of the weights on a discretely weighted vibrating string. We present several growth theorems. Two examples are also given.
On competition between modes at the onset of Bénard-Marangoni convection in a layer of fluid
Authors: Hashim Ishak 
Published: May 2019

AbstractIn this paper we use classical linear stability theory to analyse the onset of steady and oscillatory Bénard-Marangoni convection in a horizontal layer of fluid in the more physically-relevant case when both the non-dimensional Rayleigh and Marangoni numbers are linearly dependent. We present examples of situations in which there is competition between modes at the onset of convection when the layer is heated from below.
Juglans regia (walnut) in temperate arable agroforestry systems: effects on soil characteristics, arthropod diversity and crop yield
Authors: Pardon P. , Mertens J. , Reubens B. , Reheul D. , Coussement T. , Elsen A. , Nelissen V. , Verheyen K. 
Published: May 2019

AbstractAgroforestry (AF) is considered to be a sustainable land use practice as it combines agricultural production with multiple beneficial effects such as carbon sequestration, enhanced nutrient cycling and increased biodiversity. Quantification of these beneficial effects in temperate arable fields is still limited, however, and most studies focus on one sole parameter (i.e., impact on crop productivity, soil quality, biodiversity, etc.). Combined effects are only rarely considered, resulting in a lack of integrated quantification. Here we assess the effect of rows of walnut trees (Juglans regia L.) on soil organic carbon (SOC), soil nutrient status, the presence of potentially beneficial ground-dwelling arthropods and on the yield and quality of neighboring arable crops. Significantly higher SOC and soil nutrient concentrations were found near the trees, which is assumed to be primarily a result of tree leaf litter input. Abundance of macro-detritivorous arthropods was increased in and near the tree rows, whereas only limited effects of tree presence were found on the presence of the predatory arthropod taxa under study. The yield of all crops under study was reduced as a result of tree presence, with the strongest reductions observed for grain maize and sugar beet near the trees (<10 m). In addition, alteration of crop quality was observed near tree rows with decreased dry matter concentration of grain samples and increased crude protein concentration of winter cereals.
Species‐Dependent Chromium Isotope Fractionation Across the Eastern Tropical North Pacific Oxygen Minimum Zone
Authors: Wang Xiangli , Glass Jennifer B. , Reinhard Chris T. , Planavsky Noah J. 
Published: May 2019

AbstractThe stable chromium (Cr) isotope system is an emerging paleoredox proxy. Interpretation of sedimentary and seawater δ53Cr (53Cr/52Cr relative to SRM 979) hinges on our understanding of the isotopic fractionations during Cr sequestration from seawater to sediments. Seawater δ53Cr values reported thus far are for total dissolved Cr. This study reports the δ53Cr of both dissolved Cr (III) and dissolved Cr (VI) across the oxygen minimum zone in the eastern tropical North Pacific off Manzanillo, Mexico. Dissolved Cr (III) accounts for 48% to 54% total dissolved Cr in this region. There are no correlations between O2 and Cr concentrations, or O2 concentrations and δ53Cr throughout the water column. The δ53Cr of Cr (III) is lower than that of Cr (VI) by a relatively constant offset (0.42 ± 0.15‰, 1σ, n = 5) and is also uncorrelated with dissolved O2 concentration. These observations provide part of the foundation for using δ53Cr of the authigenic Cr in organic‐rich shales to reconstruct seawater δ53Cr. A survey of growing literature Cr concentration and δ53Cr data suggests that the Cr isotope fractionation factor in the global ocean is likely more complex than previously thought. More future species‐dependent Cr isotope studies could shed new light on the biogeochemical processes controlling the oceanic Cr isotope fractionation.
Shallow Low‐Frequency Tremor in the Northern Japan Trench Subduction Zone
Authors: Tanaka Sachiko , Matsuzawa Takanori , Asano Youichi 
Published: May 2019

AbstractWe found offshore shallow low‐frequency tremor in the northern Japan Trench subduction zone, using records from the Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench. The tremor aligned with a narrow zone, which follows the 10‐ to 25‐km depth contours of the plate interface and occurred in two distinct areas, off Tokachi and Sanriku, separated by a gap. In the 1.75 years examined, two episodes lasting for a few weeks were identified off Tokachi. During these episodes, tremor occurred concurrently with swarms of very low frequency earthquakes and migrated laterally about 120 km along the trench strike. In contrast, tremor off Sanriku lasted shorter (half a day to 5 days) and repeated at shorter intervals (1–4 months). The variation in tremor behavior such as duration, recurrence, migration, and the association with very low frequency earthquakes suggests along‐strike heterogeneities in frictional properties at the shallow plate interface.
Identifying immunologically-vulnerable regions of the HCV E2 glycoprotein and broadly neutralizing antibodies that target them
Authors: Quadeer Ahmed A. , Louie Raymond H. Y. , McKay Matthew R. 
Published: May 2019

AbstractIsolation of broadly neutralizing human monoclonal antibodies (HmAbs) targeting the E2 glycoprotein of Hepatitis C virus (HCV) has sparked hope for effective vaccine development. Nonetheless, escape mutations have been reported. Ideally, a potent vaccine should elicit HmAbs that target regions of E2 that are most difficult to escape. Here, aimed at addressing this challenge, we develop a predictive in-silico evolutionary model for E2 that identifies one such region, a specific antigenic domain, making it an attractive target for a robust antibody response. Specific broadly neutralizing HmAbs that appear difficult to escape from are also identified. By providing a framework for identifying vulnerable regions of E2 and for assessing the potency of specific antibodies, our results can aid the rational design of an effective prophylactic HCV vaccine.
Gas reactions under intrapore condensation regime within tailored metal–organic framework catalysts
Authors: Agirrezabal-Telleria Iker , Luz Ignacio , Ortuño Manuel A. , Oregui-Bengoechea Mikel , Gandarias Iñaki , López Núria , Lail Marty A. , Soukri Mustapha 
Published: May 2019

AbstractProduction of 1-butene, a major monomer in polymer industry, is dominated by homogeneous protocols via ethylene dimerization. Homogeneous catalysts can achieve high selectivity but require large amounts of activators and solvents, and exhibit poor recyclability; in turn, heterogeneous systems are robust but lack selectivity. Here we show how the precise engineering of metal–organic frameworks (MOFs) holds promise for a sustainable process. The key to the (Ru)HKUST-1 MOF activity is the intrapore reactant condensation that enhances ethylene dimerization with high selectivity (> 99% 1-butene) and high stability (> 120 h) in the absence of activators and solvents. According to spectroscopy, kinetics, and modeling, the engineering of defective nodes via controlled thermal approaches rules the activity, while intrapore ethylene condensation accounts for selectivity and stability. The combination of well-defined actives sites with the concentration effect arising from condensation regimes paves the way toward the development of robust MOF catalysts for diverse gas-phase reactions.
Bacterial hopping and trapping in porous media
Authors: Bhattacharjee Tapomoy , Datta Sujit S. 
Published: May 2019

AbstractDiverse processes—e.g. bioremediation, biofertilization, and microbial drug delivery—rely on bacterial migration in disordered, three-dimensional (3D) porous media. However, how pore-scale confinement alters bacterial motility is unknown due to the opacity of typical 3D media. As a result, models of migration are limited and often employ ad hoc assumptions. Here we reveal that the paradigm of run-and-tumble motility is dramatically altered in a porous medium. By directly visualizing individual Escherichia coli, we find that the cells are intermittently and transiently trapped as they navigate the pore space, exhibiting diffusive behavior at long time scales. The trapping durations and the lengths of “hops” between traps are broadly distributed, reminiscent of transport in diverse other disordered systems; nevertheless, we show that these quantities can together predict the long-time bacterial translational diffusivity. Our work thus provides a revised picture of bacterial motility in complex media and yields principles for predicting cellular migration.
Deep-sea benthic communities in the largest oceanic desert are structured by the presence of polymetallic crust
Authors: Delavenne Juliette , Keszler Louise , Castelin Magalie , Lozouet Pierre , Maestrati Philippe , Samadi Sarah 
Published: May 2019

AbstractBased on the specimens collected during three deep-sea cruises, and deposited at the Muséum National d’Histoire Naturelle (MNHN) in Paris, we analysed the diversity of benthic communities within the EEZ of French Polynesia. The literature and the MNHN database allowed us to inventory 471 species of invertebrates, among which 169 were newly described. We mainly found data for Mollusca, Crustacea, Brachiopoda and Crinoidea. We also found samples from other taxa, which still remain unidentified within the collections of the MNHN. Although this inventory is incomplete, we demonstrate that the deep waters of French Polynesia host unique benthic communities and endemic species. Using diversity and multivariate analyses, we show that the deep-sea benthic communities are structured by depth, habitats, geography and also by the presence of polymetallic crust. Furthermore, by focusing on the molluscs of the central area of French Polynesia, we show that the spectrum of shell size differs among deep-sea habitats. Specifically, shells tend to be smaller on encrusted seamounts than on island slopes. Together with the size range of organisms, low abundance, rarity and endemism designate these habitats as sensitive. These results should thus be taken into account in the evaluation of the expected impact of mining activities on biological communities.