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A disruption database characterizing the current quench of disruptions with ITER-like tungsten divertor has been developed on EAST. It provides a large number of plasma parameters describing the predisruptive plasma, current quench time, eddy current, and mitigation by massive impurity injection, which shows that the current quench time strongly depends on magnetic energy and post-disruption electron temperature. Further, the energy balance and magnetic energy dissipation during the current quench phase has been well analysed. Magnetic energy is also demonstrated to be dissipated mainly by ohmic reheating and inductive coupling, and both of the two channels have great effects on current quench time. Also, massive gas injection is an efficient method to speed up the current quench and increase the fraction of impurity radiation.
We examined whether breakfast frequency was associated with chronic inflammatory, as assessed by high-sensitivity C-reactive protein (CRP) concentration.
Kailuan community, China.
Included were 70 092 Chinese adults without CVD and cancer in 2014 with CRP concentrations <10 mg/l, when breakfast frequency was assessed via a questionnaire, and plasma CRP concentration was measured.
Breakfast frequency was associated with CRP concentration (P-trend < 0·001). The adjusted mean CRP was 1·33 mg/l (95 % CI 1·23, 1·44) for the ‘no breakfast’ group and 1·07 mg/l (95 % CI 1·0, 1·14) for the ‘breakfast everyday’ group (P-difference < 0·001), adjusting for age, sex, diet quality, total energy, obesity, education, occupation, marital status, smoking, alcohol consumption, blood pressure, sleep parameters, fasting blood glucose and lipid profiles. Consistently, the adjusted OR for CRP ≥ 1·0 mg/l and CRP ≥ 3·0 mg/l were 1·86 (95 % CI 1·73, 2·00) and 1·27 (95 % CI 1·15, 1·40), respectively, when comparing these two breakfast consumption groups (P-trend < 0·001 for both). The associations were more pronounced among older adults, relative to those who were younger (P-interaction < 0·001). Significant association between breakfast skipping and elevated CRP concentration was observed in those with poor diet quality, but not those with good diet quality.
Habitually skipping breakfast was associated with elevated concentrations of CRP. Future prospective studies including repeated assessment of inflammatory biomarkers and a collection of detailed information on type and amount of breakfast foods are warranted.
Damage to the corticospinal tract (CST) from stroke leads to motor deficits. The damage can be quantified as the amount of overlap between the stroke lesion and CST (CST Injury). Previous literature has shown that the degree of motor deficits post-stroke is related to the amount of CST Injury. These studies delineate the stroke lesion from structural T1-weighted magnetic resonance imaging (MRI) scans, often acquired for research. In Canada, computed tomography (CT) is the most common imaging modality used in routine acute stroke care. In this proof-of-principle study, we determine whether CST Injury, using lesions delineated from CT scans, significantly explains the variability in motor impairment in individuals with stroke.
Thirty-seven participants with stroke were included in this study. These individuals had a CT scan within the acute stage (7 days) of their stroke and underwent motor assessments. Brain images from CT scans were registered to MRI space. We performed a stepwise regression analysis to determine the contribution of CST injury and demographic variables in explaining motor impairment variability.
Using clinically available CT scans, we found modest evidence that CST Injury explains variability in motor impairment (R2adj = 0.12, p = 0.02). None of the participant demographic variables entered the model.
We show for the first time a relationship between CST Injury and motor impairment using CT scans. Further work is required to evaluate the utility of data derived from clinical CT scans as a biomarker of stroke motor recovery.
Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for ESCC. Currently, the commonly used methods for P. gingivalis detection are culture or DNA extraction-based, which are either time and labour intensive especially for high-throughput applications. We aimed to establish and evaluate a rapid and sensitive direct quantitative polymerase chain reaction (qPCR) protocol for the detection of P. gingivalis without DNA extraction which is suitable for large-scale epidemiological studies. Paired gingival swab samples from 192 subjects undergoing general medical examinations were analysed using two direct and one extraction-based qPCR assays for P. gingivalis. Tris-EDTA buffer-based direct qPCR (TE-direct qPCR), lysis-based direct qPCR (lysis-direct qPCR) and DNA extraction-based qPCR (kit-qPCR) were used, respectively, in 192, 132 and 60 of these samples for quantification of P. gingivalis. The sensitivity and specificity of TE-direct qPCR was 95.24% and 100% compared with lysis-direct qPCR, which was 100% and 97.30% when compared with kit-qPCR; TE-direct qPCR had an almost perfect agreement with lysis-direct qPCR (κ = 0.954) and kit-qPCR (κ = 0.965). Moreover, the assay time used for TE-direct qPCR was 1.5 h. In conclusion, the TE-direct qPCR assay is a simple and efficient method for the quantification of oral P. gingivalis and showed high sensitivity and specificity compared with routine qPCR.
Fluid motion has two well-known fundamental processes: the vector transverse process characterized by vorticity, and the scalar longitudinal process consisting of a sound mode and an entropy mode, characterized by dilatation and thermodynamic variables. The existing theories for the sound mode involve the multi-variable issue and its associated difficulty of source identification. In this paper, we define the source of sound inside the fluid by the objective causality inherent in dynamic equations relevant to a longitudinal process, which naturally favours the material time-rate operator
rather than the local time-rate operator
, and describes the sound mode by inhomogeneous advective wave equations. The sources of sound physical production inside the fluid are then examined at two levels. For the conventional formulation in terms of thermodynamic variables at the first level, we show that the universal kinematic source can be condensed to a scalar invariant of the surface deformation tensor. Further, in the formulation in terms of dilatation at the second level, we find that the sound mode in viscous and heat-conducting flow has sources from rich nonlinear couplings of vorticity, entropy and surface deformation, which cannot be disclosed at the first level. Preliminary numerical demonstration of the theoretical findings is made for two typical compressible flows, i.e. the interaction of two corotating Gaussian vortices and the unsteady type IV shock/shock interaction. The results obtained in this study provide a new theoretical basis for, and physical insight into, understanding various nonlinear longitudinal processes and the interactions therein.
To assess the impact of lisdexamfetamine dimesylate (LDX; Vyvanse®, Shire US Inc.), which is the first long-acting prodrug stimulant indicated for treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adults in the United States, on performance and quality of life (QOL) in adults with ADHD.
Subjects (n=142; aged 18 to 55 years) with ADHD entered a 4-week open-label dose-optimisation phase, then a 2-week, double-blind crossover phase. The primary efficacy measure was the average postdose total score on the Permanent Product Measure of Performance (PERMP) math test given predose and 2, 4, 8, 10, 12, and 14 hours postdose. The Adult ADHD Impact Module (AIM-A) was self-administered during the dose-optimisation phase. Safety was assessed by monitoring adverse events (AEs).
In the intention-to-treat population (n=105), postdose average PERMP least squares mean (SE) scores were higher (P< .0001) for LDX (312.9 [8.59]) vs placebo (289.5 [8.59]) and at every postdose time point ≥14 hours (P≤.0017 for each). Mean change from baseline scores on AIM-A subscales (n=127) showed improvement (P< .001) with LDX in 6 measured QOL domains (living with ADHD; general wellbeing; work, home, and school performance and daily functioning; relationships and communication; interference with life; and concern caused by symptoms). Treatment-emergent AEs (≥10%) in the dose-optimisation phase were decreased appetite (36.6%), dry mouth (30.3%), headache (19.7%), and insomnia (18.3%).
LDX improved QOL and performance (up to 14 hours) and demonstrated a safety profile consistent with long-acting stimulant use.
Supported by funding from Shire Development Inc., Wayne, PA, US.
There are strong links between circadian disturbance and some of the most characteristic symptoms of clinical major depressive disorder (MDD). However there are no published studies of changes in expression of clock genes or of other neuropeptides related to circadian-rhythm regulation, which may influence recurrent susceptibility after treatment with antidepressant in MDD.
Blood samples were collected from twelve healthy controls and twelve male major depressive patients pre- and post- treated with escitalopram for eight weeks at 4-hour intervals for 24 hours. Outcome measures were the relative expression of mRNA of clock genes (hPERIOD1, hPERIOD2, hPERIOD3, hCRY1, hBMAL1, hNPAS2 and hGSK-3beta) and the levels of serum melatonin, Vasoactive Intestinal Peptide (VIP), cortisol, Adrenocorticotropic Hormone (ACTH), Insulin-like Growth Factor-1(IGF-1) and growth hormone (GH) in twelve healthy controls and twelve pre- and post- treated MDD patients.
Compared with healthy controls, MDD patients showed disruptions in diurnal rhythms of expression of hPERIOD1, hPERIOD2, hCRY1, hBMAL1, hNPAS2 and hGSK-3beta, along with disruptions in diurnal rhythms of release of melatonin, VIP, cortisol, ACTH, IGF-1, and GH. Several of these disruptions (hPER1, hCRY1, melatonin, VIP, cortisol, ACTH, and IGF-1) persisted after eight weeks escitalopram treatment, as did elevation of 24-hour levels of VIP and decreases in 24-hour levels of cortisol and ACTH.
These persisted neurobiological changes may play a role in MDD symptoms that are thought to contribute to recurrence vulnerability and in maintenance therapy for a long term.
Developing empirically sound measures for social cognition is a key step in improving the factors that contribute to deficits in social functioning in schizophrenia. Investigating the psychometric properties and acceptability of social cognitive instruments may contribute to identification of a reliable and valid instrument for schizophrenia patients.
To investigate the psychometric properties and acceptability of a dynamic social cognition scale (DSCB) compared to three common social cognition instruments in schizophrenia.
41 patients with schizophrenia were evaluated to assess acceptability, internal consistency and validity of five social cognition measures: DSCB, Emotion Recognition-40 (ER-40), Facial Emotion Identification Task (FEIT), Tone Matching Task and MSCEIT. Multiple linear regressions were conducted to identify variables which perform well as social cognition determinants.
The DSCB and FEIT showed good acceptability, evidenced by shorter administration time, completion and patient preference for the DSCB. Good levels of internal consistency were found for the DSCB (α = 0.851), ER-40 (α = 0.803), and FEIT (α = 0.782). Confirmatory Factor Analysis indicated sufficient to good model fit. The DSCB and the ER-40 demonstrated a good model fit. The correlations for the DSCB were significant for the ER-40 (r = 0.512) and FEIT (r = 0.500).
Findings suggest that DSCB is the preferred instrument to evaluate social cognition, due to its dynamic nature and short administration time. Further research is needed to develop and improve these measurements. Additionally, the DSCB, FEIT and ER-40 show adequate to good reliability and validity.
The PANSS is utilized in clinical trials for assessment of psychopathology. In order to determine the status of a patient, comparisons within a general population are necessary. If several groups of patients are to be compared, gender, age, co-morbid diagnoses, and other factors affecting clinical status are not identically distributed.
1) Phase 1: To establish the initial psychometric properties of the PANSS-Ru. 2) Phase 2: To establish normed-reference data for the PANSS-Ru.
Phase 1: 40 patients with schizophrenia and other psychotic disorders. Phase 2: 375 individuals (n = 250 patients; n = 125 controls). Responses were assessed for internal consistency, stability, reliability, discriminative validity, and construct validity. Fifth percentile norms are presented as step functions. Data were compared to US norms.
40 subjects enrolled for Phase 1. Alpha coefficient of 0.88 verified good internal consistency. Test-retest comparisons verified time stability (r = 0.67 to 0.92). Correlation between subscale and the total scores ranged from 0.76 to 0.86, compared to > 0.83 for US norm studies. Internal consistencies were α > 0.745. Mean subscale/ total score were equivalent to US population norms within 13%. However, there was a difference of > 5 norm-based points for mean general psychopathology subscale. Norms had a sensitivity of 85% and specificity of 89%.
Preliminary results show that different dimensions of symptom presentations in the Russian population may help to improve symptom-specific treatments, and will also provide comparison data for a Russian population. Further normative studies are warranted in other populations.
Deficits in social functioning, including communication, work, social skills, and community functioning, are a defining feature of schizophrenia. Functional outcomes of schizophrenia are affected by several factors such as social cognition, neurocognition, psychopathology, and clinical outcomes. The multifaceted association among these factors and functional outcome continues to be unclear. Given the significant role of functional outcomes in schizophrenia, there has been increasing importance in factors that may underlie these outcomes. If the characteristics of these factors can be defined, interventions may be developed to improve them, which, in turn, will have a parallel impact on long term functioning and outcome. The current study examines whether social cognition, neurocognition and clinical symptoms have a relationship on functional outcomes in patients with schizophrenia.
37 patients with DSM-IV schizophrenia were assessed for: Neurocognition; MCCB-MATRICS, Clinical Symptoms: PANSS, Social Cognition: MSCEIT, Emotion Recognition-40 (ER-40), Dynamic Social Cognition Battery (DSCB: Emotion Identification - Facial, Verbal and Non Verbal), Functional Outcomes: University of San Diego Performance Based Assessment (USCD-UPSA), Social Skills: Personal and Social Performance Scale (PSP). Structural Equation Modeling (SEM) employed with maximum likelihood estimation for test effects.
The overall model fit was χ2=39.6, P<0.14. Fit indexes: Cmin/df=1.25, NFI=0.96, Tucker-Lewis index (Bentler and Bonnet nonformed fit index)=0.97, RMSEA=0.044. Regression weights of the latent variable 'Marder Negative Factor' were significant and high (β=0.91) and a substantial amount of variance could be explained by negative symptoms, indicating that the negative factor is a reliable measure of the latent variable. In addition, the regression weights of the latent variable social cognition to the 3 indicators were moderate and significant (Emotion Recognition DSCB: β=0.77, ER-40: β=0.46, and Nonverbal Emotion Identification, β=0.44). Like social cognition, the latent variable functional assessment explained a substantial amount of variance in the latent variables of working memory (45%). Impact of social cognition on negative symptoms (β=0.91) was greater than the direct impact of social functioning (β=0.78) and functional assessments (β=0.63).
This study suggests that 49% of negative symptoms could be explained by impaired social cognition and that 49% of social functioning skills could be explained by social cognition. Our findings suggest that social cognition may be an essential target to improve functional outcomes. These findings provide evidence that may help develop novel interventions.
Muscle fiber characteristics comprise a set of complex traits that influence the meat quality and lean meat production of livestock. However, the genetic and biological mechanisms regulating muscle fiber characteristics are largely unknown in pigs. Based on a genome-wide association study (GWAS) performed on 421 Large White × Min pig F2 individuals presenting well-characterized phenotypes, this work aimed to detect genome variations and candidate genes for five muscle fiber characteristics: percentage of type I fibers (FIB1P), percentage of type IIA fibers (FIB2AP), percentage of type IIB fibers (FIB2BP), diameter of muscle fibers (DIAMF) and number of muscle fibers per unit area (NUMMF). The GWAS used the Illumina Porcine SNP60K genotypic data, which were analyzed by a mixed model. Seven and 10 single nucleotide polymorphisms (SNPs) were significantly associated with DIAMF and NUMMF, respectively (P < 1.10E-06); no SNP was significantly associated with FIB1P, FIB2AP or FIB2B. For DIAMF, the significant SNPs on chromosome 4 were located in the previously reported quantitative trait loci (QTL) interval. Because the significant SNPs on chromosome 6 were not mapped in the previously reported QTL interval, a putative novel QTL was suggested for this locus. None of the previously reported QTL intervals on chromosomes 6 and 14 harbored significant SNPs for NUMMF; thus, new potential QTLs on these two chromosomes are suggested in the present work. The most significant SNPs associated with DIAMF (ALGA0025682) and NUMMF (MARC0046984) explained 12.02% and 11.59% of the phenotypic variation of these traits, respectively. In addition, both SNPs were validated as associated with DIAMF and NUMMF in Beijing Black pigs (P < 0.01). Some candidate genes or non-coding RNAs, such as solute carrier family 44 member 5 and miR-124a-1 for DIAMF, and coiled-coil serine rich protein 2 for NUMMF, were identified based on their close location to the significant SNPs. This study revealed some genome-wide association variants for muscle fiber characteristics, and it provides valuable information to discover the genetic mechanisms controlling these traits in pigs.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Latrophilin (LPH) is known as an adhesion G-protein-coupled receptor which involved in multiple physiological processes in organisms. Previous studies showed that lph not only involved the susceptibility to anticholinesterase insecticides but also affected fecundity in Tribolium castaneum. However, its regulatory mechanisms in these biological processes are still not clear. Here, we identified two potential downstream carboxylesterase (cce) genes of Tclph, esterase4 and esterase6, and further characterized their interactions with Tclph. After treatment of T. castaneum larvae with carbofuran or dichlorvos insecticides, the transcript levels of Tcest4 and Tcest6 were significantly induced from 12 to 72 h. RNAi against Tcest4 or Tcest6 led to the higher mortality compared with the controls after the insecticides treatment, suggesting that these two genes play a vital role in detoxification of insecticides in T. castaneum. Furthermore, with insecticides exposure to Tclph knockdown beetles, the expression of Tcest4 was upregulated but Tcest6 was downregulated, indicating that beetles existed a compensatory response against the insecticides. Additionally, RNAi of Tcest6 resulted in 43% reductions in female egg laying and completely inhibited egg hatching, which showed the similar phenotype as that of Tclph knockdown. These results indicated that Tclph affected fecundity by positively regulating Tcest6 expression. Our findings will provide a new insight into the molecular mechanisms of Tclph involved in physiological functions in T. castaneum.
Although application of organic fertilizers has become a recommended way for developing sustainable agriculture, it is still unclear whether above-ground and below-ground crops have similar responses to chemical fertilizers (CF) and organic manure (OM) under the same farming conditions. The current study investigated soil quality and crop yield response to fertilization of a double-cropping system with rapeseed (above-ground) and sweet potato (below-ground) in an infertile red soil for 2 years (2014–16). Three fertilizer treatments were compared, including CF, OM and organic manure plus chemical fertilizer (MCF). Organic fertilizers (OM and MCF) increased the yield of both above- and below-ground crops and improved soil biochemical properties significantly. The current study also found that soil-chemical properties were the most important and direct factors in increasing crop yields. Also, crop yield was affected indirectly by soil-biological properties, because no significant effects of soil-biological activities on yield were detected after controlling the positive effects of soil-chemical properties. Since organic fertilizers could not only increase crop yield, but also improve soil nutrients and microbial activities efficiently and continuously, OM application is a reliable agricultural practice for both above- and below-ground crops in the red soils of China.
To investigate the morphology and dimensions of the vestibular aqueduct on axial, single-oblique and double-oblique computed tomography images.
The computed tomography temporal bone scans of 112 patients were retrospectively evaluated. Midpoint and opercular measurements were performed using axial, single-oblique and double-oblique images. Morphometric analyses were also conducted. The vestibular aqueduct sizes on axial, single-oblique and double-oblique images were compared.
At the midpoint, the mean (± standard deviation) vestibular aqueduct measured 0.61 ± 0.23 mm, 0.74 ± 0.27 mm and 0.82 ± 0.38 mm on axial, single-oblique and double-oblique images, respectively; at the operculum, the vestibular aqueduct measured 0.91 ± 0.30 mm, 1.11 ± 0.45 mm and 1.66 ± 1.07 mm on the respective images. The co-efficients of variation of the vestibular aqueduct measured at the midpoint were 37.4 per cent, 36.5 per cent and 47.5 per cent on axial, single-oblique and double-oblique images, respectively; at the operculum, the measurements were 33.0 per cent, 40.5 per cent and 64.5 per cent. Regarding morphology, the vestibular aqueduct was fissured (33.5 per cent), tubular (64.3 per cent) or invisible (2.2 per cent).
The morphology and dimensions of the vestibular aqueduct were highly variable among axial, single-oblique and double-oblique images.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Two phases of diabase-sill-forming magmatism are recorded within the Badu anticline where magmas were emplaced into upper Palaeozoic carbonates and clastic rocks of the Youjiang fold-and-thrust belt in the SW South China Block, China. Zircons from these diabase units yield weighted mean U–Pb ages of 249.2±2.0 Ma and 187.1±3.3 Ma, and magmatic oxygen fugacity values from ‒20 to ‒6 (average of ‒12, equating to FMQ +5) and ‒20 to ‒10 (average of ‒15, equating to FMQ +2), respectively. These data indicate that the sills were emplaced during Early Triassic and Early Jurassic times. The discovery of c. 250 Ma mafic magmatism in this area was probably related to post-flood-basalt extension associated with the Emeishan mantle plume or rollback of the subducting Palaeo-Tethys slab. The c. 190 Ma diabase sills indicate that the southwestern South China Block records Early Jurassic mafic magmatism and lithospheric extension that was likely associated with a transition from post-collisional to within-plate tectonic regimes. The emplacement of diabase intrusions at depth may have driven hydrothermal systems, enabling the mobilization of elements from sedimentary rocks and causing the formation of a giant epigenetic metallogenic domain. The results indicate that high-oxygen-fugacity materials within basement rocks caused crustal contamination of the magmas, contributing to the wide range of oxygen fugacity conditions recorded by the Au-bearing Badu diabase. In addition, data from inherited xenocrystic zircons within the Badu diabase and detrital zircons from basement rocks suggest that the Neoproterozoic Jiangshao suture extends to the south of the Badu anticline.
Gut microbes, especially those in the large intestine, are actively involved in nutrient metabolism; however, their impact on host nitrogen (N) metabolism remains largely unknown. This study was designed to investigate the effects of feeding a cocktail of antibiotics (AGM) (ampicillin, gentamycin and metronidazole) on intestinal microbiota, N utilization efficiency, and amino acid (AA) digestibility in cannulated pigs, with the aim of exploring the impact of gut microbiota on host N metabolism. In total, 16 piglets were surgically fitted with a simple distal ileal T-cannula and a jugular venous catheter. The pigs were fed a basal diet without antibiotics (control; CON) or with antibiotics (antibiotic; ANTI), for 2 weeks. The results showed that feeding AGM did not affect weight gain or digestive enzyme activity. The antibiotics increased the concentration of urea N (P<0.05). However, they reduced N utilization, and the total tract apparent digestibility of isoleucine, methionine, valine, tyrosine and total AA (P<0.05). Furthermore, the antibiotics increased the terminal ileum apparent digestibility of CP, phenylalanine, valine, alanine, tyrosine and total AA (P<0.05). AGM markedly altered the composition of the microbiota in the ileum and feces, with a reduction in populations of Bifidobacterium, Lactobacillus and Ruminococcus, and an increase in the abundance of Escherichia coli (P<0.05). The antibiotics also significantly increased the concentration of cadaverine and ammonia, both in ileal digesta and feces (P<0.05), suggesting a marked impact on N metabolism in the intestine. The analyses indicated that the alteration of gut microbiota was correlated with the apparent digestibility of CP and AA in the intestine. These findings suggest that the AGM-induced alteration of gut microbiota may contribute to the change in intestinal N metabolism, and consequently, N excretion from the body. These results also suggest that antibiotics could have a significant effect on host N metabolism. The present study contributes to our understanding of the effects of antibiotics and provides a rational scientific basis for diet formulation during AGM use.
In this study, a micromechanics model has been proposed for predicting the effects of particle size and aggregation on elastic properties of nanocomposites, and the interphase between the particle and matrix is also taken into account. Inherent characteristics of nanoparticle, such as small size and high surface area ratio, make nanoparticle in a state of unstable energy and easy to agglomerate in matrix. The analytical expressions for the effective elastic modulus of nanocomposites are derived, which can consider the effect of particle agglomeration. The dispersion state or degree of agglomeration of nanoparticle and the thickness and stiffness of interphase are known to have a significant influence on nanocomposites. The results show that the increase of particle radius and agglomeration volume fractions reduces the elastic stiffness of nanocomposites. Moreover, the composite reinforcement can be improved by increases of interphase thickness and stiffness.