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Unbalanced metabolic status in the weeks after calving predisposes dairy cows to metabolic and infectious diseases. Blood glucose, IGF-I, non-esterified fatty acids (NEFA) and β-hydroxybutyrate (BHB) are used as indicators of the metabolic status of cows. This work aims to (1) evaluate the potential of milk mid-IR spectra to predict these blood components individually and (2) to evaluate the possibility of predicting the metabolic status of cows based on the clustering of these blood components. Blood samples were collected from 241 Holstein cows on six experimental farms, at days 14 and 35 after calving. Blood samples were analyzed by reference analysis and metabolic status was defined by k-means clustering (k=3) based on the four blood components. Milk mid-IR analyses were undertaken on different instruments and the spectra were harmonized into a common standardized format. Quantitative models predicting blood components were developed using partial least squares regression and discriminant models aiming to differentiate the metabolic status were developed with partial least squares discriminant analysis. Cross-validations were performed for both quantitative and discriminant models using four subsets randomly constituted. Blood glucose, IGF-I, NEFA and BHB were predicted with respective R2 of calibration of 0.55, 0.69, 0.49 and 0.77, and R2 of cross-validation of 0.44, 0.61, 0.39 and 0.70. Although these models were not able to provide precise quantitative values, they allow for screening of individual milk samples for high or low values. The clustering methodology led to the sharing out of the data set into three groups of cows representing healthy, moderately impacted and imbalanced metabolic status. The discriminant models allow to fairly classify the three groups, with a global percentage of correct classification up to 74%. When discriminating the cows with imbalanced metabolic status from cows with healthy and moderately impacted metabolic status, the models were able to distinguish imbalanced group with a global percentage of correct classification up to 92%. The performances were satisfactory considering the variables are not present in milk, and consequently predicted indirectly. This work showed the potential of milk mid-IR analysis to provide new metabolic status indicators based on individual blood components or a combination of these variables into a global status. Models have been developed within a standardized spectral format, and although robustness should preferably be improved with additional data integrating different geographic regions, diets and breeds, they constitute rapid, cost-effective and large-scale tools for management and breeding of dairy cows.
Schizophrenia (SZ) is a severe neuropsychiatric disorder associated with disrupted connectivity within the thalamic-cortico-cerebellar network. Resting-state functional connectivity studies have reported thalamic hypoconnectivity with the cerebellum and prefrontal cortex as well as thalamic hyperconnectivity with sensory cortical regions in SZ patients compared with healthy comparison participants (HCs). However, fundamental questions remain regarding the clinical significance of these connectivity abnormalities.
Resting state seed-based functional connectivity was used to investigate thalamus to whole brain connectivity using multi-site data including 183 SZ patients and 178 matched HCs. Statistical significance was based on a voxel-level FWE-corrected height threshold of p < 0.001. The relationships between positive and negative symptoms of SZ and regions of the brain demonstrating group differences in thalamic connectivity were examined.
HC and SZ participants both demonstrated widespread positive connectivity between the thalamus and cortical regions. Compared with HCs, SZ patients had reduced thalamic connectivity with bilateral cerebellum and anterior cingulate cortex. In contrast, SZ patients had greater thalamic connectivity with multiple sensory-motor regions, including bilateral pre- and post-central gyrus, middle/inferior occipital gyrus, and middle/superior temporal gyrus. Thalamus to middle temporal gyrus connectivity was positively correlated with hallucinations and delusions, while thalamus to cerebellar connectivity was negatively correlated with delusions and bizarre behavior.
Thalamic hyperconnectivity with sensory regions and hypoconnectivity with cerebellar regions in combination with their relationship to clinical features of SZ suggest that thalamic dysconnectivity may be a core neurobiological feature of SZ that underpins positive symptoms.
Breeding programmes for the Holstein-Friesian have historically focused on improved milk production with little emphasis on functional traits such as fertility or disease resistance (Yan et al., 2006). Recently, a major breeding programme has been adopted in Northern Ireland using the cross-breeding technique (Holstein cows x Jersey sires) with the aim of improving fertility and disease resistance of dairy cows whilst maintaining milk production capacity. The objectives of the present study were to evaluate possible breed differences in the efficiency of energy utilisation between Holstein and Jersey-Holstein dairy cows offered mixed diets of grass silage with a low or high level of concentrates.
There is little information available in the literature on the validation of the currently adopted energy feeding systems developed from calorimetric data, using data obtained in production studies. The objective of the present study was to use production data from feeding studies to validate some metabolisable energy (ME) systems (AFRC, 1990 and 1993; SCA, 1990) and net energy (NE) systems (Van Es, 1978, INRA, 1989; NRC, 2001).
AFRC (1993) recommends a reduction of proportionately 0.018 in dietary metabolisble energy (ME) concentration with each unit increase in feeding level above maintenance in dairy cows (feeding level is calculated as total ME intake divided by ME requirement for maintenance). A similar value (0.016) was reported recently by Yan et al. (2001) using a number of linear and multiple regression techniques with lactating dairy cows offered grass silage-based diets. The objectives of the present study were to validate these two values and also to evaluate the effects of feeding level on nutrient digestibility and ME concentration in the mixed diets.
The energy feeding systems currently adopted for dairy cows in Western Europe and North America were developed from calorimetric data published 30 years ago. However, the calorimetric measurements were usually undertaken with a small number of trained animals, housed for a short period in respiration chambers. The objective of the present study was to use production data to develop the metabolisable energy (ME) requirement for maintenance (MEm) and the efficiency of ME use for lactation (kl) for dairy cows.
Wilting of grass prior to ensiling generally produces positive responses in dry matter (DM) intake of cattle, but the responses in animal performance are often small, or even negative. The primary objective of the present study was to compare energy utilization from heavily wilted and unwilted silages by growing cattle when given at equal metabolisable energy (ME) intakes. A secondary objective was to evaluate effects of silage additive type (inoculant v. formic acid) on energy utilization.
Four silages were produced from unwilted and wilted grasses (DM 193 and 450 g/kg) obtained from a perennial ryegrass sward. The wilted grass was dried in the field for 26 hours using rapid wilting techniques involving crop conditioning and spreading. At ensiling both the unwilted and wilted grasses were each treated with two additives, a bacterial inoculant (Ecosyl, Zeneca Bioproducts Limited) and a formic acid additive (ADD-F, BP Chemicals Ltd.).
Adverse psychosocial working environments characterized by job strain (the combination of high demands and low control at work) are associated with an increased risk of depressive symptoms among employees, but evidence on clinically diagnosed depression is scarce. We examined job strain as a risk factor for clinical depression.
We identified published cohort studies from a systematic literature search in PubMed and PsycNET and obtained 14 cohort studies with unpublished individual-level data from the Individual-Participant-Data Meta-analysis in Working Populations (IPD-Work) Consortium. Summary estimates of the association were obtained using random-effects models. Individual-level data analyses were based on a pre-published study protocol.
We included six published studies with a total of 27 461 individuals and 914 incident cases of clinical depression. From unpublished datasets we included 120 221 individuals and 982 first episodes of hospital-treated clinical depression. Job strain was associated with an increased risk of clinical depression in both published [relative risk (RR) = 1.77, 95% confidence interval (CI) 1.47–2.13] and unpublished datasets (RR = 1.27, 95% CI 1.04–1.55). Further individual participant analyses showed a similar association across sociodemographic subgroups and after excluding individuals with baseline somatic disease. The association was unchanged when excluding individuals with baseline depressive symptoms (RR = 1.25, 95% CI 0.94–1.65), but attenuated on adjustment for a continuous depressive symptoms score (RR = 1.03, 95% CI 0.81–1.32).
Job strain may precipitate clinical depression among employees. Future intervention studies should test whether job strain is a modifiable risk factor for depression.
The present study was undertaken to examine the effect of cow genetic merit on enteric methane (CH4) emission rate. The study used a data set from 32 respiration calorimeter studies undertaken at this Institute between 1992 and 2010, with all studies involving lactating Holstein-Friesian dairy cows. Cow genetic merit was defined as either profit index (PIN) or profitable lifetime index (PLI), with these two United Kingdom genetic indexes expressing the expected improvement in profit associated with an individual cow, compared with the population average. While PIN is based solely on milk production, PLI includes milk production and a number of other functional traits including health, fertility and longevity. The data set had a large range in PIN (n=736 records, −£30 to +£63) and PLI (n=548 records, −£131 to +£184), days in milk (18 to 354), energy corrected milk yield (16.0 to 45.6 kg/day) and CH4 emission (138 to 598 g/day). The effect of cow genetic merit (PIN or PLI) was evaluated using ANOVA and linear mixed modelling techniques after removing the effects of a number of animal and diet factors. The ANOVA was undertaken by dividing each data set of PIN and PLI into three sub-groups (PIN:<£3, £3 to £15 and >£15, PLI:<£23, £23 to £67 and >£67) with these being categorised as low, medium and high genetic merit. Within the PIN and PLI data sets there was no significant differences among the three sub-groups in terms of CH4 emission per kg feed intake or per kg energy corrected milk yield, or CH4 energy (CH4-E) output as a proportion of energy intake. Linear regression using the whole PIN and PLI data sets also demonstrated that there was no significant relationship between either PIN or PLI, and CH4 emission per kg of feed intake or CH4-E output as a proportion of energy intake. These results indicate that cow genetic merit (PIN or PLI) has little effect on enteric CH4 emissions as a proportion of feed intake. Instead enteric CH4 production may mainly relate to total feed intake and dietary nutrient composition.
Optical properties and thermal relaxation dynamics of resonantly excited plasmons are important in applications for optoelectronics, biomedicine, energy, and catalysis. Geometric optics of polydimethylsiloxane (PDMS) thin films containing uniformly or asymmetrically distributed polydisperse reduced AuNPs or uniformly distributed monodisperse solution-synthesized AuNPs were recently evaluated using a compact linear algebraic sum. Algebraic calculation of geometric transmission, reflection, and attenuation for AuNP-PDMS films provides a simple, workable alternative to effective medium approximations, computationally expensive methods, and fitting of experimental data. This approach allows for the summative optical responses of a sequence of 2D elements comprising a 3D assembly to be analyzed. Thin PDMS films containing 3-7 micron layers of reduced AuNPs were fabricated with a novel diffusive-reduction synthesis technique. Rapid diffusive reduction of AuNPs into asymmetric PDMS thin films provided superior photothermal response relative to thicker films with AuNPs reduced throughout, with a photon-to-heat conversion of up to 3000°C/watt which represents 3-230-fold increase over previous AuNP-functionalized systems. Later work showed that introduction of AuNPs into PDMS enhanced thermoplasmonic dissipation coincident with internal reflection of incident resonant irradiation. Measured thermal emission and dynamics of AuNP-PDMS thin films exceeded emission and dynamics attributable by finite element analysis to Mie absorption, Fourier heat conduction, Rayleigh convection, and Stefan-Boltzmann radiation. Refractive-index matching experiments and measured temperature profiles indicated AuNP-containing thin films internally reflected light and dissipated power transverse to the film surface. Enhanced thermoplasmonic dissipation from metal-polymer nanocomposite thin films could affect opto- and bio-electronic implementation of these systems.
This paper describes the system architecture of a newly constructed radio telescope – the Boolardy engineering test array, which is a prototype of the Australian square kilometre array pathfinder telescope. Phased array feed technology is used to form multiple simultaneous beams per antenna, providing astronomers with unprecedented survey speed. The test array described here is a six-antenna interferometer, fitted with prototype signal processing hardware capable of forming at least nine dual-polarisation beams simultaneously, allowing several square degrees to be imaged in a single pointed observation. The main purpose of the test array is to develop beamforming and wide-field calibration methods for use with the full telescope, but it will also be capable of limited early science demonstrations.
To identify the predictors of psychotropic medication use and to determine rates and patterns of use in Northern Ireland (NI) among the general population and various subgroups.
Analysis of data from the NI Study of Health and Stress, a representative household survey undertaken between 2004 and 2008 with 4340 individuals. Respondents were asked about prescribed psychotropic medication use in the previous 12 months along with a series of demographic questions and items regarding experience of traumatic life events. Mental health disorders were assessed using the World Health Organization's Composite International Diagnostic Interview.
Females, individuals aged 50–64 years old, those who were previously married, and those who had experienced a traumatic lifetime event were more likely to have taken any psychotropic medication. Use of any psychotropic medication in the population in the previous 12 months was 14.9%. Use among individuals who met the criteria for a 12-month mental health disorder was 38.5%. Almost one in ten individuals (9.4%) had taken an antidepressant.
Compared with other countries, NI has high proportions of individuals using psychotropic medication in both the general population and those who met the criteria for a 12-month mental disorder. However, these results still suggest possible under treatment of mental disorders in the country. In addition, rates of use in those with no disorder are relatively high. The predictors of medication use are similar to findings in other countries. Possible research and policy implications are discussed.
Modeling of the mechanical behavior of a two-phased material, even with a simple microstructure such as a single crystal superalloy remains a difficult task, for lack of phase specific experimental data. The combination of Three Crystal Diffractometry with high energy synchrotron radiation and in situ experiments can give access to such data in real time. A few examples are given on load transfer between phases, dislocation densities, and the stress – strain behavior of a phase.
A rules-driven, informatics-based approach to multiply-constrained materials design is outlined, employing the example of polymer coating design for silica fibers. This approach to the inverse mapping problem of structure generation from design constraints and quantitative structure-property relationships (QSPRs) emphasizes design rule generation and analysis. Using this approach addresses several issues in new materials discovery: 1) factoring a larger design problem into tractable components, 2) integrating physical and non-physical requirements (such as cost), 3) identifying information gaps that must be resolved to complete a design, and 4) identifying situations in which a solution consistent with known information is not feasible.
With our present concern for a secure environment, the development of new radiation detection materials has focused on the capability of identifying potential radiation sources at increased sensitivity levels. As the initial framework for a materials-informatics approach to radiation detection materials, we have explored the use of both supervised (Support Vector Machines – SVM and Linear Discriminant Analysis – LDA) and unsupervised (Principal Component Analysis – PCA) learning methods for the development of structural signature models. Application of these methods yields complementary results, both of which are necessary to reduce parameter space and variable degeneracy. Using a crystal structure classification test, the use of the nonlinear SVM significantly increases predictive performance, suggesting trade-offs between smaller descriptor spaces and simpler linear models.
While some metal-oxide surfaces can be classified as acidic, after reacting with H2SO4 their acidity can be even higher than the parent sulfuric acid. In this paper, ab initio electronic structure calculations (3-21G+*//3-21G*) were performed on a series of model surfaces to examine these sulfonated species as strong, possibly even superacids. Our results indicate that the polarizing nature of the metal-oxide / sulfonate interaction stabilizes strong Bronsted and Lewis acid sites at the M-O surface and the sulfur center. Thermodynamic analysis has been performed to provide information for experimental verification.