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Starch digestion in the small intestines of the dairy cow is low, to a large extent, due to a shortage of syntheses of α-amylase. One strategy to improve the situation is to enhance the synthesis of α-amylase. The mammalian target of rapamycin (mTOR) signalling pathway, which acts as a central regulator of protein synthesis, can be activated by leucine. Our objectives were to investigate the effects of leucine on the mTOR signalling pathway and to define the associations between these signalling activities and the synthesis of pancreatic enzymes using an in vitro model of cultured Holstein dairy calf pancreatic tissue. The pancreatic tissue was incubated in culture medium containing l-leucine for 3 h, and samples were collected hourly, with the control being included but not containing l-leucine. The leucine supplementation increased α-amylase and trypsin activities and the messenger RNA expression of their coding genes (P <0.05), and it enhanced the mTOR synthesis and the phosphorylation of mTOR, ribosomal protein S6 kinase 1 and eukaryotic initiation factor 4E-binding protein 1 (P <0.05). In addition, rapamycin inhibited the mTOR signal pathway factors during leucine treatment. In sum, the leucine regulates α-amylase and trypsin synthesis in dairy calves through the regulation of the mTOR signal pathways.
We numerically verify better fluid mixing efficiency can be achieved by alternating injection scheme in a heterogeneous porous medium, whose permeability heterogeneity is characterized by two statistical parameters, i.e., the variance s and the correlation length l. Nevertheless, the fingering pattern is strongly affected by permeability distribution to result in similar fingering interface on each of injected layer of less viscous fluids. Instead of randomly chaotic fingering interaction in a homogeneous condition, more orderly channeling interaction occurs in a heterogeneous medium. As a result, higher Peclet number Pe (relative measure of advection and diffusion effects) generally leads to worse mixing efficiency in a heterogeneous medium, which might contradict the result found in a homogeneous case. By the same token, in the cases which strong chaotic fingering interaction already exists in homogeneous conditions, e.g., sufficiently short alternating injection interval Δt, large viscosity contrast A and high Pe, the presence of permeability heterogeneity would constrain the randomly chaotic fingering interaction and favors the more orderly channeling interaction, so that mixing efficiency is deteriorated compared with the corresponding homogeneous case.
This study aimed to estimate the disease burden of hepatitis E in a rural region in China. A total of 489 hepatitis E cases were reported according to a community-based survey in an active hepatitis surveillance system between 2008 and 2015, the questionnaire and record-review methods were constructed to evaluate the economic and health burden of hepatitis E virus infections from societal perspectives. All costs were converted to US$ in 2015. The age-standardized cumulative incidence rate was 107·9/100 000, and the median age-standardized annual incidence rate was 16·5/100 000. The median direct, indirect, and intangible cost were $1046·0, $49·1, and $77·3/patient, respectively, and the median economic burden per patient was $1836·5, which accounted for 51·2% of per capita disposable income. Moreover, the median quality-adjusted life year and visual analogue scale score were 0·7 and 70·0/case, respectively. Both economic burden and health burden of inpatients was more serious than that of outpatients (P < 0·001). Disease burden of hepatitis E is heavy on patients, their families, and society. More studies on the disease burden of hepatitis E are necessary to increase social awareness of the disease and confirm reasonable disease-control measures.
Three epidemic waves of human influenza A(H7N9) were documented in several different provinces in China between 2013 and 2015. With limited understanding of the potential for human-to-human transmission, it was difficult to implement control measures efficiently or to inform the public adequately about the application of interventions. In this study, the human-to-human transmission rate for the epidemics that occurred between 2013 and 2015 in Zhejiang Province, China, was analysed. The reproduction number (R), a key indicator of transmission intensity, was estimated by fitting the number of infections from poultry to humans and from humans to humans into a mathematical model. The posterior mean R for human-to-human transmission was estimated to be 0·27, with a 95% credible interval of 0·14–0·44 for the first wave, whereas the posterior mean Rs decreased to 0·15 in the second and third waves. Overall, these estimates indicate that a human H7N9 pandemic is unlikely to occur in Zhejiang. The reductions in the viral transmissibility and the number of poultry-transmitted infections after the first epidemic may be attributable to the various intervention measures taken, including changes in the extent of closures of live poultry markets.
In this talk, we will show the beaming effect for Fermi/LAT blazars, then we discuss the correlations between γ-ray luminosity and other parameters, such as radio Doppler factors, superluminal motions, and core-dominance parameters. We also compare the Doppler factors determined from the γ-ray luminosity, X-ray emissions, and the short-term time scales with those from other methods. Our discussions suggest that γ-ray emissions may be strongly beamed.
In this work, we reported the optical photometry monitoring results for two brightest nearby quasars, PHL 1811 and 3C 273 using the ST-6 camera at Abastumani Observatory, Georgia. For PHL 1811, we found 3 microvariability events with time scale of ΔT = 6.0 min. For 3C273, we found that the largest variations are ΔV = 0.369 ± 0.028 mag, ΔR = 0.495 ± 0.076 mag, and ΔI = 0.355 ± 0.009 mag. When periodicity analysis methods are adopted to the available data, a period of p = 5.80 ± 1.12 years is obtained for PHL 1811, and p = 21.10 ± 0.14, 10.00 ± 0.14, 7.30 ± 0.09, 13.20 ± 0.09, 2.10 ± 0.06, and 0.68 ± 0.05 years are obtained for 3C 273.
Variability is one of the extreme observational properties of BL Lacertae objects. AO 0235+164 is a well studied BL Lac through the whole electro-magnetic wavebands, it is violently variable in the optical bands. In the present work, we show its optical R band photometric observations carried out during the period of Nov. 2006 to Dec. 2012 using the Ap6E CCD camera attached to the primary focus of the 70 cm meniscus telescope at Abastumani Observatory, Georgia. It shows a large variation of ΔR = 4.88 mag (14.20 - 19.08 mag) during our monitoring period. When periodicity analysis methods are adopted to its R observations from our Abastumani monitoring programme and those in the literature, the signs of some periods, P1 = 8.26 yr, P2 = 0.55 yr, P3 = 0.85 yr, P4 = 1.99 yr are found.
Although variation in the long-term course of major depressive disorder (MDD) is not strongly predicted by existing symptom subtype distinctions, recent research suggests that prediction can be improved by using machine learning methods. However, it is not known whether these distinctions can be refined by added information about co-morbid conditions. The current report presents results on this question.
Data came from 8261 respondents with lifetime DSM-IV MDD in the World Health Organization (WHO) World Mental Health (WMH) Surveys. Outcomes included four retrospectively reported measures of persistence/severity of course (years in episode; years in chronic episodes; hospitalization for MDD; disability due to MDD). Machine learning methods (regression tree analysis; lasso, ridge and elastic net penalized regression) followed by k-means cluster analysis were used to augment previously detected subtypes with information about prior co-morbidity to predict these outcomes.
Predicted values were strongly correlated across outcomes. Cluster analysis of predicted values found three clusters with consistently high, intermediate or low values. The high-risk cluster (32.4% of cases) accounted for 56.6–72.9% of high persistence, high chronicity, hospitalization and disability. This high-risk cluster had both higher sensitivity and likelihood ratio positive (LR+; relative proportions of cases in the high-risk cluster versus other clusters having the adverse outcomes) than in a parallel analysis that excluded measures of co-morbidity as predictors.
Although the results using the retrospective data reported here suggest that useful MDD subtyping distinctions can be made with machine learning and clustering across multiple indicators of illness persistence/severity, replication with prospective data is needed to confirm this preliminary conclusion.
Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?
Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus.
Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.
MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.
The survival behaviour of Vibrio cholerae in cholera epidemics, together with its attributes of virulence-associated genes and molecular fingerprints, are significant for managing cholera epidemics. Here, we selected five strains representative of V. cholerae O1 and O139 involved in cholera events, examined their survival capacity in large volumes of water sampled from epidemic sites of a 2005 cholera outbreak, and determined virulence-associated genes and molecular subtype changes of the surviving isolates recovered. The five strains exhibited different survival capacities varying from 17 to 38 days. The virulence-associated genes of the surviving isolates remained unchanged, while their pulsotypes underwent slight variation. In particular, one waterway-isolated strain maintained virulence-associated genes and evolved to share the same pulsotype as patient strains, highlighting its role in the cholera outbreak. The strong survival capacity and molecular attributes of V. cholerae might account for its persistence in environmental waters and the long duration of the cholera outbreak, allowing effective control measures.
The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?
Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.
The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.
MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.
The head and neck region is the second most frequent anatomical site of extranodal lymphomas. These tumours affect many individuals worldwide, justifying epidemiological studies in different countries. This study evaluated the characteristics, treatments and prognostic factors for non-Hodgkin's lymphoma of the head and neck in Chinese patients.
The clinical manifestations, clinicopathological characteristics, multidisciplinary treatment and prognostic factors for 102 patients with extranodal non-Hodgkin's lymphoma of the head and neck were analysed retrospectively.
The tonsil was the most commonly involved primary site, followed by the nasal cavity. The most common histological subtype was diffuse large B-cell lymphoma, followed by natural killer T-cell lymphoma. Patients receiving a combination of rituximab and chemotherapy did better than those receiving chemotherapy alone. Prognosis was significantly associated with both International Prognostic Index and histological subtype; the former was especially strongly associated with poor survival.
In this group of Chinese patients, diffuse large B-cell lymphoma was the most common pathological subtype, but the incidence of T-cell lymphomas was higher than that reported in the USA. Combined rituximab and chemotherapy led to better outcomes than chemotherapy alone. Prognosis depended on both International Prognostic Index and histological subtype.
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.
The relationship between recurrent major depression (MD) in women and suicidality is complex. We investigated the extent to which patients who suffered with various forms of suicidal symptomatology can be distinguished from those subjects without such symptoms.
We examined the clinical features of the worst episode in 1970 Han Chinese women with recurrent DSM-IV MD between the ages of 30 and 60 years from across China. Student's t tests, and logistic and multiple logistic regression models were used to determine the association between suicidality and other clinical features of MD.
Suicidal symptomatology is significantly associated with a more severe form of MD, as indexed by both the number of episodes and number of MD symptoms. Patients reporting suicidal thoughts, plans or attempts experienced a significantly greater number of stressful life events. The depressive symptom most strongly associated with lifetime suicide attempt was feelings of worthlessness (odds ratio 4.25, 95% confidence interval 2.9–6.3). Excessive guilt, diminished concentration and impaired decision-making were also significantly associated with a suicide attempt.
This study contributes to the existing literature on risk factors for suicidal symptomatology in depressed women. Identifying specific depressive symptoms and co-morbid psychiatric disorders may help improve the clinical assessment of suicide risk in depressed patients. These findings could be helpful in identifying those who need more intense treatment strategies in order to prevent suicide.
Two dimensional Er3+-TeO2 thin film photonics crystals (PhCs) are fabricated. These PhCs demonstrate broadband enhancement of PL emission at near Infrared (NIR). The PhC structures are written by dual beam focused ion beam (FIB). Highly uniformed patterns with smooth surfaces are observed. A pattern resolution better than hundred nanometers is achieved. PhCs arrays with photonic lattice constants from 350 nm to 1700 nm are examined in order to optimize the PL extraction efficiency. Strong photoluminescence around 1530 nm is observed by 488-532 nm lasers pumping. A confocal microscopy with spectrometer is used to capture the broadband PL signals from individual PhC array.
The emission enhancement factor and spectral dependent extraction ratio are analyzed to find the interaction between PL lightwave and PhC structures. By optimize the PhC structures, 1500 um-1560 um broadband PL is successfully converted between the PL emission layer and the external cavity. A 60 % enhancement of surface extraction efficiency is achieved when PhC with periodicity a=800 nm is applied. When photonic lattice constants a are smaller than the critical periodicity 600 nm, the PL light becomes confined inside the thin film layer. Simulation is also performed by two dimensional finite difference time domain (FDTD) calculation in order to explain the experimental observed anisotropic PL enhancements.
The broadband PL enhancement enables Er3+-TeO2 PhCs thin film as a potential light source for three dimensional integrated photonic circuits.