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In two-dimensional (2D) electron systems, the viscous flow is dominant when electron-electron collisions occur more frequently than the impurity or phonon scattering. In this work, a quantum hydrodynamic model, considering viscosity, is proposed to investigate the interaction of a charged particle moving above the two-dimensional viscous electron gas. The stopping power, perturbed electron gas density, and the spatial distribution of the velocity vector field have been theoretically analyzed and numerically calculated. The calculation results show that viscosity affects the spatial distribution and amplitude of the velocity field. The stopping power, which is an essential quantity for describing the interactions of ions with the 2D electron gas, is calculated, indicating that the incident particle will suffer less energy loss due to the weakening of the dynamic electron polarization and induced electric field in 2D electron gas with the viscosity. The values of the stopping power may be more accurate after considering the effect of viscosity. Our results may open up new possibilities to control the interaction of ions with 2D electron gas in the surface of metal or semiconductor heterostructure by variation of the viscosity.
Preterm birth is a global health problem and associated with increased risk of long-term developmental impairments, but findings on the adverse outcomes of prematurity have been inconsistent.
Methods
Data were obtained from the baseline session of the ongoing longitudinal Adolescent Brain and Cognitive Development (ABCD) Study. We identified 1706 preterm children and 1865 matched individuals as Control group and compared brain structure (MRI data), cognitive function and mental health symptoms.
Results
Results showed that preterm children had higher psychopathological risk and lower cognitive function scores compared to controls. Structural MRI analysis indicated that preterm children had higher cortical thickness in the medial orbitofrontal cortex, parahippocampal gyrus, temporal and occipital gyrus; smaller volumes in the temporal and parietal gyrus, cerebellum, insula and thalamus; and smaller fiber tract volumes in the fornix and parahippocampal-cingulum bundle. Partial correlation analyses showed that gestational age and birth weight were associated with ADHD symptoms, picvocab, flanker, reading, fluid cognition composite, crystallized cognition composite and total cognition composite scores, and measures of brain structure in regions involved with emotional regulation, attention and cognition.
Conclusions
These findings suggest a complex interplay between psychopathological risk and cognitive deficits in preterm children that is associated with changes in regional brain volumes, cortical thickness, and structural connectivity among cortical and limbic brain regions critical for cognition and emotional well-being.
For the omnivorous Cherax quadricarinatus crayfish, plant raw materials can be good alternatives to dietary fish meal (FM). A 56-d feeding trial was conducted in C. quadricarinatus (11·70 (se 0·13) g). Diet with 100 % FM as the protein source was the control. Seven experimental diets were formulated by replacing 75 or 100 % of FM with soyabean meal (SM75, SM100) or cottonseed meal (CM75 and CM100), and a mixture of SM and CM (protein content is 1:1) replacing 50, 75 or 100 % of FM (SC50, SC75 and SC100). Crayfish fed the CM100 and SC100 showed significantly lower weight gain (WG), specific growth rate, trypsin and pepsin activities compared with the control diet. Crayfish in CM100 group showed significantly higher GPx, alanine aminotransferase, aspartate aminotransferase activities and malondialdehyde content than the control. SM100 and CM100 diets can cause slight separation of the peritrophic membrane from the intestinal folds. The pepsin activity of crayfish in SC50 was significantly higher than those in other experimental diets. The highest WG and muscle arginine content were also found in crayfish fed SC50. The relative abundance of Proteobacteria, Unclassified Enterobacteriaceae and Candidatus Bacilloplasma was significantly higher, but Actinobacteriota was significantly lower in SM100, CM100 and SC100 than in control. Microbiota functional prediction indicated that the relative abundance of ‘cell motility’ pathway in crayfish fed CM100 was significantly decreased compared with the control. In conclusion, only half of the FM can be effectively substituted with a mixture of SM and CM (protein content is 1:1) for C. quadricarinatus.
According to the positive time-discounting assumption of intertemporal decision-making, people prefer to undergo negative events in the future rather than in the present. However, negative discounting has been identified in the intertemporal choice and loss domains, which refers to people’s preference to experience negative events earlier rather than later. Studies have validated and supported the "anticipated dread" as an explanation for negative discounting. This study again explored the effect of anticipated dread on intertemporal choice using content analysis; that is, having participants identify anticipated dread among reasons for negative discounting. This study also validated the effect of anticipated dread on negative discounting by manipulating anticipated dread. This study adds empirical and direct evidence for the role of anticipated dread in negative discounting.
Intertemporal choices involve tradeoffs between outcomes that occur at different times. Most of the research has used pure gains tasks and the discount rates yielding from those tasks to explain and predict real-world behaviors and consequences. However, real decisions are often more complex and involve mixed outcomes (e.g., sooner-gain and later-loss or sooner-loss and later-gain). No study has used mixed gain-loss intertemporal tradeoff tasks to explain and predict real-world behaviors and consequences, and studies involving such tasks are also scarce. Considering that tasks involving a combination of gains and losses may yield different discount rates and that existing pure gains tasks do not explain or predict real-world outcomes well, this study conducted two experiments to compare the discount rates of mixed gain-loss intertemporal tradeoffs with those of pure gains or pure losses (Experiment 1) and to examine whether these tasks predicted different real-world behaviors and consequences (Experiment 2). Experiment 1 suggests that the discount rate ordering of the four tasks was, from highest to lowest, pure gains, sooner-loss and later-gain, pure losses, and sooner-gain and later-loss. Experiment 2 indicates that the evidence supporting the claim that the discount rates of the four tasks were related to different real-world behaviors and consequences was insufficient.
Mechanistic studies have suggested that antioxidants have beneficial effects on age-related macular degeneration (AMD). This study aimed to investigate the association between the types and sources of dietary vitamin and carotenoid intakes and AMD risk in China. A matched case–control study of 260 AMD cases and 260 matched controls was performed. The participants were interviewed for dietary information and potential confounders, and comprehensive ophthalmic examinations were performed. Conditional logistic models were used to estimate the odds ratio (OR) and 95 % confidence interval (CI) of specific vitamins and carotenoids and their main sources. When comparing the extreme quartiles, the ORs (95 % CI) were 0·30 (0·10, 0·88) for lutein and 0·28 (0·11, 0·74) for β-cryptoxanthin. The associations for other dietary vitamin and carotenoid intakes were generally weaker and non-significant. Higher intakes of spinach and egg, which are important sources of lutein, were associated with a reduced odds of AMD. ORs (95% CIs) comparing extreme categories were 0·42 (0·20, 0·88) for spinach and 0·52 (95% CI: 0·27, 0·98) for egg. Participants who were in the highest category of both egg intake and spinach intake had a much greater reduced odds of having AMD (OR: 0·23; 95% CI: 0·08, 0·71) than those in the lowest category of egg intake and spinach intake. In conclusion, a higher intake of lutein and lutein-rich foods was associated with a significantly decreased odds of AMD. These findings provide further evidence of the benefits of lutein and lutein-rich foods in the prevention of AMD.
Insulin-like growth factor 1 receptor (IGF1R) is a cell surface receptor, belonging to the tyrosine kinase receptor superfamily. IGF1R plays a role not only in normal cell development but also in malignant transformation, which has become a candidate therapeutic target for the treatment of human cancer. This study aimed to explore insertions and deletions (indels) in IGF1R gene and investigate their association with growth traits in four Chinese cattle breeds (Xianan cattle, Jinnan cattle, Qinchuan cattle and Nanyang cattle). The current paper identified a 28-bp indel by polymerase chain reaction within IGF1R gene. The analysis showed that there was a significant correlation between the locus and the hucklebone width of Nanyang cattle in four periods, in which it was highly correlated at 6, 12 and 18 months. At the age of 6 months, it was also significantly correlated with body height, body weight and body length. Association analysis showed that the locus in Jinnan cattle was extremely significantly correlated with body slanting length and body weight, and significantly correlated with chest circumference. There was no significant correlation between this locus and growth traits of Xianan cattle and Qinchuan cattle. The detected indel in the IGF1R gene was significantly associated with growth traits in Jinnan and Nanyang cattle, and could be used as a molecular marker for growth trait selection.
Detailed balance of a chemical reaction network can be defined in several different ways. Here we investigate the relationship among four types of detailed balance conditions: deterministic, stochastic, local, and zero-order local detailed balance. We show that the four types of detailed balance are equivalent when different reactions lead to different species changes and are not equivalent when some different reactions lead to the same species change. Under the condition of local detailed balance, we further show that the system has a global potential defined over the whole space, which plays a central role in the large deviation theory and the Freidlin–Wentzell-type metastability theory of chemical reaction networks. Finally, we provide a new sufficient condition for stochastic detailed balance, which is applied to construct a class of high-dimensional chemical reaction networks that both satisfies stochastic detailed balance and displays multistability.
To measure the associations of sociodemographic and behavioural factors with fruit and vegetable consumption among adults in China.
Design:
A cross-sectional study.
Setting:
A 2015 wave of the China Health and Nutrition Survey.
Participants:
Totally, 11 910 adults aged 18 to 64 years.
Results:
Adjusted log binomial regression analyses showed that adults with higher income levels had higher fruit intake than those with low income levels (medium income group, risk ratio (RR): 1·28; 95 % CI: 1·16, 1·41; high income group, RR: 1·58; 95 % CI: 1·43, 1·74). Current smokers had lower fruit intake than non-smokers (RR: 0·86; 95 % CI: 0·77, 0·96). Adults living in southern China had higher vegetable intake (RR: 1·88; 95 % CI: 1·76, 2·01) but lower fruit intake (RR: 0·85; 95 % CI: 0·79, 0·91) than adults in northern China. With increasing age, adults had higher fruit intake (50–64 years, RR: 1·20; 95 % CI: 1·09, 1·33; reference category 18–34 years) and higher vegetable intake (35–49 years, RR: 1·13; 95 % CI: 1·05, 1·22; 50–64 years, RR: 1·22; 95 % CI: 1·13, 1·31).
Conclusions:
Our findings identify a range of sociodemographic and behavioural factors associated with fruit and vegetable consumption among Chinese adults. They also point to the need for public health nutrition interventions for socially disadvantaged populations in China.
Protoporphyrinogen oxidase (PPO) is an important target for discovering new herbicides that interfere with the synthesis of porphyrin. To discover new PPO inhibitors with improved biological activity, a series of new diphenyl ethers containing tetrahydrophthalimide were designed and synthesized. Among them, J6.1 (IC50 = 4.7 nM) and J6.3 (IC50 = 30.0 nM) show higher maize (Zea mays L.) PPO inhibitory activity than the commercial herbicides oxyfluorfen (IC50 = 117.9 nM) and flumioxazin (IC50 = 157.1 nM). The greenhouse herbicidal activity of J6.3 is comparable to that of oxyfluorfen, and it is greater than that of flumioxazin. Even at a dose of 300 g ai ha−1, cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) show greater tolerance to J6.3, suggesting that J6.3 could be used for further development of new herbicide candidates in those fields. In addition, molecular docking has been used to further study the mechanism of action of J6.3. The results show that the introduction of a nitro group and tetrahydrophthalimide into the diphenyl ether structure is beneficial to biological activity.
Dietary salt intake may vary depending on different lifestyles. We aimed to estimate the different salt intakes and evaluate the knowledge and self-awareness about salt among people speaking the Teochew, Teochew–Hakka and Hakka dialects in the Chaoshan region of southern China.
Design:
The study followed a cluster sampling of residents in Chaoshan region. General characteristics, lifestyles, health status as well as knowledge and self-awareness related to salt intake were investigated using a questionnaire. Anthropometric variables as well as Na and K excretion in a 24-h urine collection were measured.
Setting:
Chaoshan region of China.
Participants:
Four hundred fifteen adults who spoke only one of these three dialects.
Results:
The salt intake of adults who spoke the Teochew, Teochew–Hakka and Hakka dialects was 7·19 (interquartile range (IQR) 5·29–10·17), 9·03 (IQR 6·62–11·54) and 10·12 (IQR 7·61–12·82) g/d, respectively, with significant differences between Teochew and Teochew–Hakka speakers and between Teochew and Hakka speakers (both P < 0·05). The Na:K ratio for adults who spoke the three dialects was 3·00 (IQR 2·00–4·11), 3·50 (IQR 2·64–4·82) and 4·52 (IQR 3·35–5·97), respectively, and differed significantly among the groups (all P < 0·05). Multiple linear regression analysis showed increased Na:K ratio associated with hypertension (β = 0·71, P = 0·043) in Hakka speakers. Knowledge and self-awareness about salt intake were poor in this population.
Conclusions:
Salt intake was closely related to lifestyles and was higher than the upper limit (5 g/d) recommended by the WHO in adults of Chaoshan, especially those speaking the Hakka dialect.
The jungles of Linyun and Longlin Autonomous Prefecture, located in the heart of the southwestern Guangxi Zhuang Autonomous Region of China, are home to the oldest tea trees (Camellia sinensis) in the world. In the absence of regular annual rings, radiocarbon (14C) dating is one of the most powerful tools that can assist in the determination of the ages and growth rates of these plants. In this work, cores were extracted from large ancient tea trees in a central Longlin rain forest; extraction of carbon was performed with an automated sample preparation system. The 14C levels in the tree cores were measured using accelerator mass spectrometry (AMS) at the University of Tsukuba. These measurements indicated that contrary to conventional views, the ages of trees in these forests range up to ~700 years, and the growth rate of this species is notably slow, exhibiting a long-term radial growth rate of 0.039±0.006 cm/yr. It was demonstrated that 14C analyses provide accurate determination of ages and growth rates for subtropical wild tea trees.
l-Carnitine is essential for mitochondrial β-oxidation and has been used as a lipid-lowering feed additive in humans and farmed animals. d-Carnitine is an optical isomer of l-carnitine and dl-carnitine has been widely used in animal feeds. However, the functional differences between l- and d-carnitine are difficult to study because of the endogenous l-carnitine background. In the present study, we developed a low-carnitine Nile tilapia model by treating fish with a carnitine synthesis inhibitor, and used this model to investigate the functional differences between l- and d-carnitine in nutrient metabolism in fish. l- or d-carnitine (0·4 g/kg diet) was fed to the low-carnitine tilapia for 6 weeks. l-Carnitine feeding increased the acyl-carnitine concentration from 3522 to 10 822 ng/g and alleviated the lipid deposition from 15·89 to 11·97 % in the liver of low-carnitine tilapia. However, as compared with l-carnitine group, d-carnitine feeding reduced the acyl-carnitine concentration from 10 822 to 5482 ng/g, and increased lipid deposition from 11·97 to 20·21 % and the mRNA expression of the genes involved in β-oxidation and detoxification in the liver. d-Carnitine feeding also induced hepatic inflammation, oxidative stress and apoptosis. A metabolomic investigation further showed that d-carnitine feeding increased glycolysis, protein metabolism and activity of the tricarboxylic acid cycle and oxidative phosphorylation. Thus, l-carnitine can be physiologically utilised in fish, whereas d-carnitine is metabolised as a xenobiotic and induces lipotoxicity. d-Carnitine-fed fish demonstrates increases in peroxisomal β-oxidation, glycolysis and amino acid degradation to maintain energy homeostasis. Therefore, d-carnitine is not recommended for use in farmed animals.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
Astrophysical collisionless shocks are amazing phenomena in space and astrophysical plasmas, where supersonic flows generate electromagnetic fields through instabilities and particles can be accelerated to high energy cosmic rays. Until now, understanding these micro-processes is still a challenge despite rich astrophysical observation data have been obtained. Laboratory astrophysics, a new route to study the astrophysics, allows us to investigate them at similar extreme physical conditions in laboratory. Here we will review the recent progress of the collisionless shock experiments performed at SG-II laser facility in China. The evolution of the electrostatic shocks and Weibel-type/filamentation instabilities are observed. Inspired by the configurations of the counter-streaming plasma flows, we also carry out a novel plasma collider to generate energetic neutrons relevant to the astrophysical nuclear reactions.
Femtosecond laser direct writing (FsLDW) in transparent materials is a laser-based precise three-dimensional (3D) micro/nanofabrication method that has shown great potential for applications. The advantages of FsLDW originate in the nonlinear nature of absorption in the multiphoton absorption process. Over the past few years, transparent material micro/nanofabrication using FsLDW has seen several developments in materials and applications. Specifically, two-photon polymerization has been widely used as a precision direct-writing process for fabrication of polymeric 3D micro/nanostructures; internal/surface ablation of polymer 3D structures based on multiphoton absorption has been demonstrated and developed as a promising subtractive manufacturing technique; and femtosecond laser multiphoton modification in glass has been intensively studied for refractive-index change and generation of nanogratings and microvoids. This article describes the latest research on FsLDW in polymers and glasses with specific applications for large-dimension fabrication, microelectromechanical systems, microphotonics, and microfluidics.
Co-infections of cystic echinococcosis (CE) and HIV/AIDS is rare. We report four CE cases that were HIV positive. Three out of the four patients underwent a surgical operation to remove the hydatid cysts in their livers. The operation confirmed that in two of the cases their cysts had ruptured. These patients were given 3 months of albendazole after the operation. Follow-up showed they were remarkably improved in term of their health, although they were still HIV antibody positive 6 months after surgical treatment. Interestingly, the treatment remarkably increased their CD4+ cell population. We showed that surgery is suitable for treating hepatic cystic echinococcosis with HIV/AIDS co-infection.
This paper presents a new Lagrangian type scheme for solving the Euler equations of compressible gas dynamics. In this new scheme the system of equations is discretized by Runge-Kutta Discontinuous Galerkin (RKDG) method, and the mesh moves with the fluid flow. The scheme is conservative for the mass, momentum and total energy and maintains second-order accuracy. The scheme avoids solving the geometrical part and has free parameters. Results of some numerical tests are presented to demonstrate the accuracy and the non-oscillatory property of the scheme.
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.
Method
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.
Results
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.
Conclusions
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.