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Reducing dietary CP content is an effective approach to reduce animal nitrogen excretion and save protein feed resources. However, it is not clear how reducing dietary CP content affects the nutrient digestion and absorption in the gut of ruminants, therefore it is difficult to accurately determine how much reduction in dietary CP content is appropriate. This study was conducted to investigate the effects of reduced dietary CP content on N balance, intestinal nutrient digestion and absorption, and rumen microbiota in growing goats. To determine N balance, 18 growing wether goats (25.0 ± 0.5 kg) were randomly assigned to one of three diets: 13.0% (control), 11.5% and 10.0% CP. Another 18 growing wether goats (25.0 ± 0.5 kg) were surgically fitted with ruminal, proximate duodenal, and terminal ileal fistulae and were randomly assigned to one of the three diets to investigate intestinal amino acid (AA) absorption and rumen microbiota. The results showed that fecal and urinary N excretion of goats fed diets containing 11.5% and 10.0% CP were lower than those of goats fed the control diet (P < 0.05). When compared with goats fed the control diet, N retention was decreased and apparent N digestibility in the entire gastrointestinal tract was increased in goats fed the 10% CP diet (P < 0.05). When compared with goats fed the control diet, the duodenal flow of lysine, tryptophan and phenylalanine was decreased in goats fed the 11.5% CP diet (P < 0.05) and that of lysine, methionine, tryptophan, phenylalanine, leucine, glutamic acid, tyrosine, essential AAs (EAAs) and total AAs (TAAs) was decreased in goats fed the 10.0% CP diet (P < 0.05). When compared with goats fed the control diet, the apparent absorption of TAAs in the small intestine was increased in goats fed the 11.5% CP diet (P < 0.05) and that of isoleucine, serine, cysteine, EAAs, non-essential AAs, and TAAs in the small intestine was increased in goats fed the 10.0% CP diet (P < 0.05). When compared with goats fed the control diet, the relative richness of Bacteroidetes and Fibrobacteres was increased and that of Proteobacteria and Synergistetes was decreased in the rumen of goats fed a diet with 10.0% CP. In conclusion, reducing dietary CP content reduced N excretion and increased nutrient utilization by improving rumen fermentation, enhancing nutrient digestion and absorption, and altering rumen microbiota in growing goats.
We examine the scaling of the two-point correlation function for
, the energy dissipation rate, over a range of values of the separation
between the two points and the Taylor microscale Reynolds number
. The correlation function is estimated from hot-wire measurements in grid turbulence, along the axes of wakes and jets, and along the centreline of a fully developed channel flow. When
exceeds a value of approximately 300, a condition which is achieved for both plane and circular jets, the correlation function collapses over nearly all values of
when the normalization uses Kolmogorov scales. However, there is no collapse in either the power-law range or dissipative range when the normalization is on the integral (or external) length scale, which indicates that there is no self-similarity based on external scales. Although the maximum value of
is not much larger than
, the behaviour of the energy dissipation correlation function on the axes of plane and circular jets seems consistent with the first similarity hypothesis of Kolmogorov (Dokl. Akad. Nauk SSSR, vol. 30, 1941, pp. 299–303) but not with the revised phenomenology of Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85).
In several lately published studies, the association between single-nucleotide polymorphism (SNP, rs12252) of IFITM3 and the risk of influenza is inconsistent. To further understand the association between the SNP of IFITM3 and the risk of influenza, we searched related studies in five databases including PubMed published earlier than 9 November 2017. Ten sets of data from nine studies were included and data were analysed by Revman 5.0 and Stata 12.0 in our updated meta-analysis, which represented 1365 patients and 5425 no-influenza controls from four different ethnicities. Here strong association between rs12252 and influenza was found in all four genetic models. The significant differences in the allelic model (C vs. T: odds ratio (OR) = 1.35, 95% confidence interval (CI) (1.03–1.79), P = 0.03) and homozygote model (CC vs. TT: OR = 10.63, 95% CI (3.39–33.33), P < 0.00001) in the Caucasian subgroup were discovered, which is very novel and striking. Also novel discoveries were found in the allelic model (C vs. T: OR = 1.37, 95% CI (1.08–1.73), P = 0.009), dominant model (CC + CT vs. TT: OR = 1.48, 95% CI (1.08–2.02), P = 0.01) and homozygote model (CC vs. TT: OR = 2.84, 95% CI (1.36–5.92), P = 0.005) when we compared patients with mild influenza with healthy individuals. Our meta-analysis suggests that single-nucleotide T to C polymorphism of IFITM3 associated with increasingly risk of severe and mild influenza in both Asian and Caucasian populations.
Plant nitrogen (N) links with many physiological progresses of crop growth and yield formation. Accurate simulation is key to predict crop growth and yield correctly. The aim of the current study was to improve the estimation of N uptake and translocation processes in the whole rice plant as well as within plant organs in the RiceGrow model by using plant and organ maximum, critical and minimum N dilution curves. The maximum and critical N (Nc) demand (obtained from the maximum and critical curves) of shoot and root and Nc demand of organs (leaf, stem and panicle) are calculated by N concentration and biomass. Nitrogen distribution among organs is computed differently pre- and post-anthesis. Pre-anthesis distribution is determined by maximum N demand with no priority among organs. In post-anthesis distribution, panicle demands are met first and then the remaining N is allocated to other organs without priority. The amount of plant N uptake depends on plant N demand and N supplied by the soil. Calibration and validation of the established model were performed on field experiments conducted in China and the Philippines with varied N rates and N split applications; results showed that this improved model can simulate the processes of N uptake and translocation well.
The response of soil microbial communities to soil quality changes is a sensitive indicator of soil ecosystem health. The current work investigated soil microbial communities under different fertilization treatments in a 31-year experiment using the phospholipid fatty acid (PLFA) profile method. The experiment consisted of five fertilization treatments: without fertilizer input (CK), chemical fertilizer alone (MF), rice (Oryza sativa L.) straw residue and chemical fertilizer (RF), low manure rate and chemical fertilizer (LOM), and high manure rate and chemical fertilizer (HOM). Soil samples were collected from the plough layer and results indicated that the content of PLFAs were increased in all fertilization treatments compared with the control. The iC15:0 fatty acids increased significantly in MF treatment but decreased in RF, LOM and HOM, while aC15:0 fatty acids increased in these three treatments. Principal component (PC) analysis was conducted to determine factors defining soil microbial community structure using the 21 PLFAs detected in all treatments: the first and second PCs explained 89.8% of the total variance. All unsaturated and cyclopropyl PLFAs except C12:0 and C15:0 were highly weighted on the first PC. The first and second PC also explained 87.1% of the total variance among all fertilization treatments. There was no difference in the first and second PC between RF and HOM treatments. The results indicated that long-term combined application of straw residue or organic manure with chemical fertilizer practices improved soil microbial community structure more than the mineral fertilizer treatment in double-cropped paddy fields in Southern China.
The gastrointestinal tract (GIT) of animals is capable of sensing various kinds of nutrients via G-protein coupled receptor-mediated signaling transduction pathways, and the process is known as ‘gut nutrient chemosensing’. GPR40, GPR41, GPR43 and GPR119 are chemoreceptors for free fatty acids (FFAs) and lipid derivatives, but they are not well studied in small ruminants. The objective of this study is to determine the expression of GPR40, GPR41, GPR43 and GPR119 along the GIT of kid goats under supplemental feeding (S) v. grazing (G) during early development. In total, 44 kid goats (initial weight 1.35±0.12 kg) were slaughtered for sampling (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) between days 0 and 70. The expression of GPR41 and GPR43 were measured at both mRNA and protein levels, whereas GPR40 and GPR119 were assayed at protein level only. The effects of age and feeding system on their expression were variable depending upon GIT segments, chemoreceptors and expression level (mRNA or protein), and sometimes feeding system × age interactions (P<0.05) were observed. Supplemental feeding enhanced expression of GPR40, GPR41 and GPR43 in most segments of the GIT of goats, whereas G enhanced expression of GPR119. GPR41 and GPR43 were mainly expressed in rumen, abomasum and cecum, with different responses to age and feeding system. GPR41 and GPR43 expression in abomasum at mRNA level was greatly (P<0.01) affected by both age and feeding system; whereas their expression in rumen and abomasum at protein level were different, feeding system greatly (P<0.05) affected GPR41 expression, but had no effect (P>0.05) on GPR43 expression; and there were no feeding system×age interactions (P>0.05) on GPR41 and GPR43 protein expression. The expression of GPR41 and GPR43 in rumen and abomasum linearly (P<0.01) increased with increasing age (from days 0 to 70). Meanwhile, age was the main factor affecting GPR40 expression throughout the GIT. These outcomes indicate that age and feeding system are the two factors affecting chemoreceptors for FFAs and lipid derivatives expression in the GIT of kids goats, and S enhanced the expression of chemoreceptors for FFAs, whereas G gave rise to greater expression of chemoreceptors for lipid derivatives. Our results suggest that enhanced expression of chemoreceptors for FFAs might be one of the benefits of early supplemental feeding offered to young ruminants during early development.
We first analytically show, starting with the Navier–Stokes equations, that the value of the derivative flatness is controlled by pressure diffusion of energy, viscous destructive effects and large-scale effects (decay and/or production). The latter two terms tend to zero when the Taylor-microscale Reynolds number
is sufficiently large. We argue that the pressure-diffusion term should also tend to a constant at large
. Available data for the velocity derivative flatness,
, in different turbulent flows are re-examined and interpreted in the light of the finite-Reynolds-number effect. It is found that
can differ from flow to flow at moderate
; for a given flow,
may also depend on the initial conditions. The data for
in various flows, e.g. along the axis in the far field of plane and circular jets, and grid turbulence, show that it approaches a constant, with a value slightly larger than 10, when
is sufficiently large. This behaviour for
is supported, at least qualitatively, by our analytical considerations. The constancy of
violates the refined similarity hypothesis introduced by Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85) to account for the intermittency of the energy dissipation rate. It is not, however, inconsistent with Kolmogorov’s original similarity hypothesis (Dokl. Akad. Nauk SSSR, vol. 30, 1941, pp. 299–303), although we contend that the power-law relation
(Kolmogorov 1962), which is widely accepted in the literature, has in reality been almost invariably used to ‘model’ the finite-Reynolds-number effect for the laboratory data and has been strongly influenced by the weighting given to the atmospheric surface layer data. The inclusion of the latter data has misled previous investigations of how
The mammalian target of rapamycin (mTOR) has been shown to be involved in lipopolysaccharide (LPS)-induced immune responses in many mammal cells. Here, we suggest that the mTOR pathway is involved in the intestinal inflammatory responses evoked by LPS treatment in chicken embryos. The intestinal tissue from Specific pathogen free chick embryos was cultured in the presence of LPS for 2 h. Secretory immunoglobulin A (sIgA) concentrations, messenger RNA (mRNA) expression of cytokines, and protein levels of nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), mTOR and p70 ribosomal S6 kinase (p70S6K) were determined. The results showed that LPS treatment increased sIgA concentrations in a dose-dependent manner. The mRNA levels of interleukine (IL)-6, IL-8, IL-10, tumor necrosis factor-α and Toll-like receptor (TLR) 4 were upregulated by LPS treatment (P<0.05). Lipopolysaccharide increased the phosphorylation of Jun N-terminal kinase (JNK), p38 MAPK and NF-κB (P<0.05) while decreasing the phosphorylation level of mTOR (P<0.05). Supplementation of leucine at doses of 10, 20 and 40 mM dose-dependently decreased sIgA production. Leucine supplementation at 40 mM restored the phosphorylation level of mTOR and p70S6K while suppressing the phosphorylation levels of NF-κB (P<0.05) and partially down-regulating the phosphorylation of p38 MAPK and JNK. The transcription of IL-6 was significantly decreased by leucine supplementation. These results suggested that leucine could alleviate LPS-induced inflammatory responses by down-regulating NF-κB signaling pathway and evoking mTOR/p70S6K signaling pathway, which may involve in the regulation of the intestinal immune system in chicken embryos.
A numerical study was undertaken to investigate the mechanical properties of metal-ceramic multilayer micro-pillars under compression. The model system contains alternating layers of aluminum (Al) and silicon carbide (SiC) above a thick silicon (Si) substrate. The finite element analyses show that the pillar deformed in a non-uniform manner under compression, especially when a tapered side wall was included in the model. The heterogeneous feature of the structure plays a significant role in influencing the apparent stress-strain response. The elastic property of the pillar compares favorably with the true composite modulus, but a large discrepancy was found in the plastic response. The difference in deformation behavior between homogeneous pillars and multilayer pillars, along with other geometric effects, were examined in detail.
The effect of large-scale forcing on the second- and third-order longitudinal velocity structure functions, evaluated at the Taylor microscale
, is assessed in various turbulent flows at small to moderate values of the Taylor microscale Reynolds number
. It is found that the contribution of the large-scale terms to the scale by scale energy budget differs from flow to flow. For a fixed
, this contribution is largest on the centreline of a fully developed channel flow but smallest for stationary forced periodic box turbulence. For decaying-type flows, the contribution lies between the previous two cases. Because of the difference in the large-scale term between flows, the third-order longitudinal velocity structure function at
differs from flow to flow at small to moderate
. The effect on the second-order velocity structure functions appears to be negligible. More importantly, the effect of
on the scaling range exponent of the longitudinal velocity structure function is assessed using measurements of the streamwise velocity fluctuation
in the range 500–1100, on the axis of a plane jet. It is found that the magnitude of the exponent increases as
increases and the rate of increase depends on the order
. The trend of published structure function data on the axes of an axisymmetric jet and a two-dimensional wake confirms this dependence. For a fixed
, the exponent can vary from flow to flow and for a given flow, the larger
is, the closer the exponent is to the value predicted by Kolmogorov (Dokl. Akad. Nauk SSSR, vol. 30, 1941a, pp. 299–303) (hereafter K41). The major conclusion is that the finite Reynolds number effect, which depends on the flow, needs to be properly accounted for before determining whether corrections to K41, arising from the intermittency of the energy dissipation rate, are needed. We further point out that it is imprudent, if not incorrect, to associate the finite Reynolds number effect with a consequence of the modified similarity hypothesis introduced by Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85) (K62); we contend that this association has misled the vast majority of post K62 investigations of the consequences of K62.
Placental transport of vitamin D and other nutrients (e.g. amino acids, fats and glucose) to the fetus is sensitive to maternal and fetal nutritional cues. We studied the effect of maternal calorific restriction on fetal vitamin D status and the placental expression of genes for nutrient transport [aromatic T-type amino acid transporter-1 (TAT-1); triglyceride hydrolase/lipoprotein uptake facilitator lipoprotein lipase (LPL)] and vitamin D homeostasis [CYP27B1; vitamin D receptor (VDR)], and their association with markers of fetal cardiovascular function and skeletal muscle growth. Pregnant sheep received 100% total metabolizable energy (ME) requirements (control), 40% total ME requirements peri-implantation [PI40, 1–31 days of gestation (dGA)] or 50% total ME requirements in late gestation (L, 104–127 dGA). Fetal, but not maternal, plasma 25-hydroxy-vitamin D (25OHD) concentration was lower in PI40 and L maternal undernutrition groups (P<0.01) compared with the control group at 0.86 gestation. PI40 group placental CYP27B1 messenger RNA (mRNA) levels were increased (P<0.05) compared with the control group. Across all groups, higher fetal plasma 25OHD concentration was associated with higher skeletal muscle myofibre and capillary density (P<0.05). In the placenta, higher VDR mRNA levels were associated with higher TAT-1 (P<0.05) and LPL (P<0.01) mRNA levels. In the PI40 maternal undernutrition group only, reduced fetal plasma 25OHD concentration may be mediated in part by altered placental CYP27B1. The association between placental mRNA levels of VDR and nutrient transport genes suggests a way in which the placenta may integrate nutritional cues in the face of maternal dietary challenges and alter fetal physiology.
An outbreak of gastroenteritis affected 453 attendees (attack rate 28·5%) of six separate events held at a hotel in Singapore. Active case detection, case-control studies, hygiene inspections and microbial analysis of food, environmental and stool samples were conducted to determine the aetiology of the outbreak and the modes of transmission. The only commonality was the food, crockery and cutlery provided and/or handled by the hotel's Chinese banquet kitchen. Stool specimens from 34 cases and 15 food handlers were positive for norovirus genogroup II. The putative index case was one of eight norovirus-positive food handlers who had worked while they were symptomatic. Several food samples and remnants tested positive for Escherichia coli or high faecal coliforms, aerobic plate counts and/or total coliforms, indicating poor food hygiene. This large common-source outbreak of norovirus gastroenteritis was caused by the consumption of contaminated food and/or contact with contaminated crockery or cutlery provided or handled by the hotel's Chinese banquet kitchen.
It remains unclear whether the topological deficits of the white matter network documented in cross-sectional studies of chronic schizophrenia patients are due to chronic illness or to other factors such as antipsychotic treatment effects. To answer this question, we evaluated the white matter network in medication-naive first-episode schizophrenia patients (FESP) before and after a course of treatment.
We performed a longitudinal diffusion tensor imaging study in 42 drug-naive FESP at baseline and then after 8 weeks of risperidone monotherapy, and compared them with 38 healthy volunteers. Graph theory was utilized to calculate the topological characteristics of brain anatomical network. Patients’ clinical state was evaluated using the Positive and Negative Syndrome Scale (PANSS) before and after treatment.
Pretreatment, patients had relatively intact overall topological organizations, and deficient nodal topological properties primarily in prefrontal gyrus and limbic system components such as the bilateral anterior and posterior cingulate. Treatment with risperidone normalized topological parameters in the limbic system, and the enhancement positively correlated with the reduction in PANSS-positive symptoms. Prefrontal topological impairments persisted following treatment and negative symptoms did not improve.
During the early phase of antipsychotic medication treatment there are region-specific alterations in white matter topological measures. Limbic white matter topological dysfunction improves with positive symptom reduction. Prefrontal deficits and negative symptoms are unresponsive to medication intervention, and prefrontal deficits are potential trait biomarkers and targets for negative symptom treatment development.
Chinese psychiatrists have gradually started to focus on those who are deemed to be at ‘clinical high-risk (CHR)’ for psychosis; however, it is still unknown how often those individuals identified as CHR from a different country background than previously studied would transition to psychosis. The objectives of this study are to examine baseline characteristics and the timing of symptom onset, help-seeking, or transition to psychosis over a 2-year period in China.
The presence of CHR was determined with the Structured Interview for Prodromal Syndromes (SIPS) at the participants' first visit to the mental health services. A total of 86 (of 117) CHR participants completed the clinical follow-up of at least 2 years (73.5%). Conversion was determined using the criteria of presence of psychotic symptoms (in SIPS). Analyses examined baseline demographic and clinical predictors of psychosis and trajectory of symptoms over time. Survival analysis (Kaplan–Meier) methods along with Log-rank tests were performed to illustrate the relationship of baseline data to either conversion or non-conversion over time. Cox regression was performed to identify baseline predictors of conversion by the 2-year follow-up.
In total 25 (29.1%) of 86 completers transitioned to a psychotic disorder over the course of follow-up. Among the CHR sample, the mean time between attenuated symptom onset and professional help-seeking was about 4 months on average, and converters developed fully psychotic symptoms about 12 months after symptom onset. Compared with those CHR participants whose risk syndromes remitted over the course of the study, converters had significantly longer delays (p = 0.029) for their first visit to a professional in search of help. At baseline assessment, the conversion subgroup was younger, had poorer functioning, higher total SIPS positive symptom scores, longer duration of untreated prodromal symptoms, and were more often given psychosis-related diagnoses and subsequently prescribed antipsychotics in the clinic.
Chinese CHR identified primarily by a novel clinical screening approach had a 2-year transition rate comparable with those of specialised help-seeking samples world-wide. Early clinical intervention with this functionally deteriorating clinical population who are suffering from attenuated psychotic symptoms, is a next step in applying the CHR construct in China.
In order to avoid excess feed consumption during the force-feeding period in foie gras production, a dose-response experiment with seven feed consumption levels (450, 540, 630, 720, 810, 900, 990 g/day per bird) was conducted to evaluate the effects of feed consumption levels on growth performance and carcass composition of male Mule ducks from 91 to 102 days of age. One-day-old Mule ducklings (sterile and artificial hybrid of male Albatre Muscovy duck and female Pekin duck were fed a two-phase commercial diets for ad libitum intake from hatching to 91 days of age, followed by graded feeding levels of a corn diet by force-feeding from 91 to 102 days of age. Fifty-six 91-day-old male Mule ducks with similar BW were randomly assigned to seven treatments, with eight birds per treatment. Birds were housed in individual pens. At 102 days of age, final BW was measured and BW gain and feed conversion ratio of ducks from each treatment were calculated from day 91 to 102, and then all ducks were slaughtered to evaluate the yields of skin with subcutaneous fat, abdominal fat, breast meat (including pectoralis major and pectoralis minor), leg meat (including thigh and drum stick), and liver. Significant differences in BW gain, total liver weight and liver relative weight were observed among the treatments (P<0.001). According to the broken-line regression analysis, the optimal feed consumption levels of male Mule ducks from 91 to 102 days of age for maximum BW gain, total liver weight and liver relative weight were 217, 227 and 216 g feed/kg BW0.75·per day, respectively.
Self-preservation (SP) analyses are applied to the mean momentum and the scale-by-scale energy budget equations in the far wake of a circular cylinder. The scale-by-scale SP analysis, which is a two-point analysis, complements the SP analysis of the mean momentum equation. Power-law variations are derived for different length scales (e.g. the Taylor microscale and the Kolmogorov length scale) and velocity scales (e.g. the root mean square and the Kolmogorov velocity scale). Further, the SP solutions for the scale-by-scale energy budget equation are exploited to develop an exact relation to estimate the mean turbulent kinetic energy dissipation rate
on the wake axis. These SP solutions and the new
relation are well supported by hot-wire data in the far wake at a Reynolds number of 2000 based on the free stream velocity and the cylinder diameter. On the far-wake axis, both the energy spectra and the structure functions exhibit an almost perfect collapse over all wavenumbers and separations, irrespective of the set of scaling variables used for normalisation. This is consistent with a complete self-preservation (i.e. SP is satisfied at all scales of motion) in the far wake.
The transport equation for the isotropic turbulent energy dissipation rate
along the centreline in the far-wake of a circular cylinder is derived by applying the limit at small separations to the two-point energy budget equation. It is found that the imbalance between the production and the destruction of
, respectively due to vortex stretching and viscosity, is governed by both the streamwise advection and the lateral turbulent diffusion (the former contributes more to the budget than the latter). This imbalance differs intrinsically from that in other flows, e.g. grid turbulence and the flow along the centreline of a fully developed channel, where either the streamwise advection or the lateral turbulent diffusion of
governs the imbalance. More importantly, the different types of imbalance represent different constraints on the relation between the skewness of the longitudinal velocity derivative
and the destruction coefficient of enstrophy
. This results in a non-universal approach of
towards a constant value as the Taylor microscale Reynolds number
increases. For the present flow, the magnitude of
decreases initially (
) before increasing (
) towards this constant value. The constancy of
violates the modified similarity hypothesis introduced by Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85) but is consistent with the original similarity hypotheses (Kolmogorov, Dokl. Akad. Nauk SSSR, vol. 30, 1941b, pp. 299–303 (see also 1991 Proc. R. Soc. Lond. A, vol. 434, pp. 9–13)) (
), and, more importantly, with the almost completely self-preserving nature of the plane far-wake.