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The dipeptide DL-methionyl-DL-Methionine (Met-Met) has extremely low water solubility and better absorption than other methionine sources (such as DL-methionine and L-methionine) available in the market. Therefore, six diets (D1, D2, D3, D4, D5 and D6) containing 0 %, 0.07%, 0.15%, 0.21%, 0.28% and 0.38% Met-Met were formulated to investigate the effects of Met-Met on Oreochromis niloticus. The results indicated that percent weight gain and specific growth rate of fish fed with D2 and D3 diets were higher than those fed with D1, D4-D6 diets. The levels of total essential amino acid in whole body of fish fed with D3 and D4 diets were significantly higher than those fed the D1 diet. Superoxide dismutase activity and malondialdehyde content were no significant difference in fed the diet with or without Met-Met supplementation. Majority of reads derived from the fish intestines belonged to members of Fusobacteria, followed by Bacteroidetes, Proteobacteria. Diversity of intestinal microbiota and total antioxidant capacity in fish fed with D3 diet was significantly higher than that of other groups. Since due to the growth results the authors conclude the optimal proportion of Met was 0.61%, and the addition of Met-Met was 0.15% in O. niloticus.
We aimed to investigate the association between plasma retinol and incident cancer among Chinese hypertensive adults. We conducted a nested case–control study, including 231 patients with incident cancer and 231 matched controls during a median 4·5-year follow-up of the China Stroke Primary Prevention Trial. There was a significant, inverse association between retinol levels and digestive system cancer (per 10 μg/dl increases: OR 0·79; 95 % CI 0·69, 0·91). When compared with participants in the first quartile of retinol (< 52·3 μg/dl), a significantly lower cancer risk was found in participants in quartile 2–4 ( ≥ 52·3 μg/dl: OR 0·31; 95 % CI 0·13, 0·71). However, there was a U-shaped association between retinol levels and non-digestive system cancers where the risk of cancers decreased (although not significantly) with each increment of plasma retinol (per 10 μg/dl increases: OR 0·89; 95 % CI 0·60, 1·31) in participants with retinol < 68·2 μg/dl, and then increased significantly with retinol (per 10 μg/dl increase: OR 1·65; 95 % CI 1·12, 2·44) in participants with retinol ≥ 68·2 μg/dl. In conclusion, there was a significant inverse dose–response association between plasma retinol and the risk of digestive system cancers. However, a U-shaped association was observed between plasma retinol and the risk of non-digestive cancers (with a turning point approximately 68·2 μg/dl).
Schizophrenia is a complex mental disorder with high heritability and polygenic inheritance. Multimodal neuroimaging studies have also indicated that abnormalities of brain structure and function are a plausible neurobiological characterisation of schizophrenia. However, the polygenic effects of schizophrenia on these imaging endophenotypes have not yet been fully elucidated.
To investigate the effects of polygenic risk for schizophrenia on the brain grey matter volume and functional connectivity, which are disrupted in schizophrenia.
Genomic and neuroimaging data from a large sample of Han Chinese patients with schizophrenia (N = 509) and healthy controls (N = 502) were included in this study. We examined grey matter volume and functional connectivity via structural and functional magnetic resonance imaging, respectively. Using the data from a recent meta-analysis of a genome-wide association study that comprised a large number of Chinese people, we calculated a polygenic risk score (PGRS) for each participant.
The imaging genetic analysis revealed that the individual PGRS showed a significantly negative correlation with the hippocampal grey matter volume and hippocampus–medial prefrontal cortex functional connectivity, both of which were lower in the people with schizophrenia than in the controls. We also found that the observed neuroimaging measures showed weak but similar changes in unaffected first-degree relatives of patients with schizophrenia.
These findings suggested that genetically influenced brain grey matter volume and functional connectivity may provide important clues for understanding the pathological mechanisms of schizophrenia and for the early diagnosis of schizophrenia.
Swelling deformation tests of Kunigel bentonite and its sand mixtures were performed in distilled water and NaCl solution. The salinity of NaCl solution has a significant impact on the swelling properties of bentonite, but not on its surface structure. The surface structure was characterized using the fractal dimension Ds. Based on the fractal dimension, a unique curve of the em–pe relationship (em is the void ratio of montmorillonite and pe is the effective stress) at full saturation was introduced to express the swelling deformation of bentonite–sand mixtures. In mixtures with a large bentonite content, the swelling deformation always followed the em–pe relationship. In mixtures with a small bentonite content, when the effective stress reached a threshold, the void ratio of montmorillonite em deviated from the unique em–pe curve due to the appearance of a sand skeleton. The threshold of vertical pressure for mixtures in different solutions and the maximum swelling strains were estimated using the em–pe relationship. The good agreement between estimates and experimental data suggest that the em–pe relationship might be an alternative method for predicting the swelling deformation of bentonite–sand mixtures in salt solution.
The status-legitimacy hypothesis proposes that low-status groups are more inclined to justify the status quo as fair and legitimate than high-status groups. Although there are some research evidences for this hypothesis, many studies have found the opposite result, that disadvantaged groups are more dissatisfied with the social system. To resolve this disagreement, this article integrates relevant ideas and empirical research in three aspects. First, the conceptual approach emphasises that the controversy is a result of different operational definitions of social status and system justification in previous studies. The second approach, focusing on moderator variables, proposes that the disputes over past studies are probably due to moderator variables, which can influence the relationship between status and system justification. The third approach, based on psychological mechanisms, proposes that system justification theory cannot completely explain the psychological underpinnings of status differences in system justification, and in order to clarify this, it is necessary to explore other psychological processes. Future studies should continue to examine the mediation mechanisms and boundary conditions of the status-legitimacy hypothesis and may try to establish a nonlinear hypothesis. Moreover, researchers should also pay attention to the application of experimental methods and big-data methods.
Residual strain often occurs in metal when it was subjected to the tension load, random vibration, or high impact. The mild steel was selected as the research object, and the feasibility of using nonlinear ultrasonic technique to characterize the residual strain was investigated in this paper. First, the mild steel specimens were stretched to several different kinds of stress, then the nonlinear effect as well as the microstrain of each sample was measured. The results indicate that the microstrain increases with increasing applied stress and reaches a maximum value of about 0.036% as the tensile stress increases to the elastic limit. Compared with the original specimen, the nonlinear parameter of tensile specimen gradually increased within the elastic limit. This result reveals that the variation of nonlinear parameter was related to microstrain in mild steel, because the microstructure observation demonstrated that the dislocation structure was basically unchanged within the elastic limit. This research indicates that the nonlinear ultrasonic method has the promising potential to characterize the microstrain in metals.
Two benzodifuran (BDF) polymers, PBDF-C and PBDF-S, with alkyl and alkylthio substituted thiophene side-chains and benzodithiophene-4,8-dione (BDD) as the acceptor were designed and synthesized. Their optical, electrochemical properties and photovoltaic performances were systematically investigated. The polymer solar cells (PSCs) with a device structure of ITO/PEDOT:PSS/polymer:PC71BM/Ca/Al were fabricated. The PBDF-C based device showed a power conversion efficiency (PCE) of 3.01% after adding 1 vol% 1,8-diodooctane (DIO) as the solvent additive, and PBDF-S gave an enhanced PCE of 3.48% without any post-treatments. The enhancements were from the higher open-circuit voltage (Voc) and fill factor (FF). The thermal- and solvent-treatment-free processing is more favourable for the large area roll-to-roll manufacturing or printing technology for PSCs.
Robots often need to accomplish some complex tasks such as surveillance, response and obstacle avoidance. In this paper, a dynamic search method is proposed to generate optimal robot trajectories satisfying complex task requirement in uncertain environment. The LTL-A* algorithm is presented to generate a global optimal path and the A* algorithm is provided to modify the global optimal path. The task is specified by a linear temporal logic (LTL) formula, and a weighted transition system according to the known information in uncertain environment is modeled to describe the robot motion. Subsequently, a product automaton is constructed by combining the transition system with the task requirement. Based on the product automaton, the LTL-A* algorithm is proposed to generate a global optimal path. The local path planning based on the A* algorithm is employed to deal with the environment change during the process of tracking the global optimal path for the robot. The results of the simulation and experiments show that the proposed method can not only meet the complex task requirement in uncertain environment but also improve the search efficiency.
The ultra-wideband bandpass-response power divider with high-frequency selectivity is presented in this paper. This power divider consists of an impedance transformer, a filter network, and two isolation resistors. In order to realize the ultra-wideband filtering performance, parallel coupling lines and parallel open-circuit branches are applied to the second impedance converter. A resistor is added to the ends of the coupling lines to achieve good isolation and output return loss. The equivalent-circuit method is employed to analyze the presented power divider. The power divider, working at 3.45–8.29 GHz, is designed and fabricated. Two transmission zeros are generated at 2.8 and 9 GHz, respectively, and the out-of-band suppression is >13 dB. The measured results are in good agreement with the simulation ones.
A series of CoCrFeNiMox (x = 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2) high-entropy alloys were designed to develop a eutectic high-entropy alloy system and to acquire a superfine eutectic structure. The results show that for the CoCrFeNiMox alloys, with the increase of Mo content from 0.2 to 1.2, the microstructures shift from a typical dendrite structure to a hypoeutectic microstructure (x = 0.6), and then to a fully eutectic microstructure (x = 0.8) with a lamellar spacing only 110 nm, and finally culminate in the hypereutectic structure (x = 1.0, x = 1.2). The XRD results show that CoCrFeNiMox alloys have a single FCC phase when x is 0.2 or 0.4. When Mo content is over 0.6, it begins to separate Cr9Mo21Ni20 intermetallic compounds. The hardness of the CoCrFeNiMox alloys is increasing significantly from 172.8 to 763.7 HV with the increase of Mo content. Meanwhile, the fracture strength increased but the ductility decreases. Among these alloys, the CoCrFeNiMo0.6 alloy shows excellent integrated mechanical properties of compressive fracture strength and strain, which are 2051 Mpa and 23%, respectively.
Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid β-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid β-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.
Temperate glaciers are more sensitive to climate changes than polar or continental glaciers, and can drive remarkable runoff variation in local water catchments. Here we present recent glacier shrinkage and runoff change for Hailuogou glacier, a typical monsoon temperate glacier on the east slope of Mount Gongga (Minya Konga), China. The surface area of Hailuogou glacier has decreased by 3.5% (0.92 km2) between 1966 (aerial photographs) and 2007 (ASTER images). Flow measurements at a stream gauge about 500 m down-glacier commencing in 1994 display a remarkable increase in annual runoff (mostly during July–September) since 1999. Annual runoff over the same period in a nonglacierized but forested subcatchment (9.17 km2) did not experience significant change. By separating the daily rainfall component from the daily total discharge, monthly catchment water-balance series were calculated for the period 1994–2005, which shows an increasing trend of glacier storage loss. We concluded that air-temperature rise (with a trend of +0.2°C (10 a)−1 between 1988 and 2005, recorded at nearby weather stations) has had an increased effect on glacier mass loss and river runoff change during the past 20 years.
Disclosing the diagnosis of Alzheimer's disease (AD) to a patient is controversial. There is significant stigma associated with a diagnosis of AD or dementia in China, but the attitude of the society toward disclosure of such a diagnosis had not been formally evaluated prior to our study. Therefore, we aimed to evaluate the attitude toward disclosing an AD diagnosis to patients in China with cognitive impairment from their caregivers, and the factors that may affect their attitude.
We designed a 17-item questionnaire and administered this questionnaire to caregivers, who accompanied patients with cognitive impairment or dementia in three major hospitals in Shanghai, China. The caregiver's attitude toward disclosing the diagnosis of AD as evaluated by the questionnaire was compared to that of disclosing the diagnosis of terminal cancer.
A majority (95.7%) of the 175 interviewed participants (mean 14.2 years of education received) wished to know their own diagnosis if they were diagnosed with AD, and 97.6% preferred the doctor to tell their family members if they were diagnosed with AD. If a family member of the participants suffered from AD, 82.9% preferred to have the diagnosis disclosed to the patient. “Cognitive impairment” was the most accepted term by caregivers to disclose AD diagnosis in Chinese.
This study suggests most of the well-educated individuals in a Chinese urban area favored disclosing the diagnosis when they or their family members were diagnosed with AD.
This article outlines the evolution of a rescue team in responding to adenovirus prevention with a deployable field hospital. The local governments mobilized a shelter hospital and a rescue team consisting of 59 members to assist with rescue and response efforts after an epidemic outbreak of adenovirus. We describe and evaluate the challenges of preparing for deployment, field hospital maintenance, treatment mode, and primary treatment methods. The field hospital established at the rescue scene consisted of a medical command vehicle, a computed tomography shelter, an X-ray shelter, a special laboratory shelter, an oxygen and electricity supply vehicle, and epidemic prevention and protection equipment. The rescue team comprised paramedics, physicians, X-ray technicians, respiratory therapists, and logistical personnel. In 22 days, more than 3000 patients with suspected adenovirus infection underwent initial examinations. All patients were properly treated, and no deaths occurred. After emergency measures were implemented, the spread of adenovirus was eventually controlled. An emergency involving infectious diseases in less-developed regions demands the rapid development of a field facility with specialized medical personnel when local hospital facilities are either unavailable or unusable. An appropriate and detailed prearranged action plan is important for infectious diseases prevention. (Disaster Med Public Health Preparedness. 2018;12:109–114)
SG-III laser facility is now the largest laser driver for inertial confinement fusion research in China. The whole laser facility can deliver 180 kJ energy and 60 TW power ultraviolet laser onto target, with power balance better than 10%. We review the laser system and introduce the SG-III laser performance here.