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Straightplasma channels are widely used to guide relativistic intense laser pulses over several Rayleigh lengths for laser wakefield acceleration. Recently, a curved plasma channel with gradually varied curvature was suggested to guide a fresh intense laser pulse and merge it into a straight channel for staged wakefield acceleration [Phys. Rev. Lett. 120, 154801 (2018)]. In this work, we report the generation of such a curved plasma channel from a discharged capillary. Both longitudinal and transverse density distributions of the plasma inside the channel were diagnosed by analyzing the discharging spectroscopy. Effects of the gas-filling mode, back pressure and discharging voltage on the plasma density distribution inside the specially designed capillary are studied. Experiments show that a longitudinally uniform and transversely parabolic plasma channel with a maximum channel depth of 47.5 μm and length of 3 cm can be produced, which is temporally stable enough for laser guiding. Using such a plasma channel, a laser pulse with duration of 30 fs has been successfully guided along the channel with the propagation direction bent by 10.4°.
People tend to prefer smaller and sooner (SS) rewards over larger and later (LL) ones even when the latter are much larger. Previous research have identified several ways to enhance people’s patience. Adding to this literature, the current paper demonstrates that introduction of upfront losses as well as gains to both SS and LL rewards can decrease people’s impatience. This effect is incompatible with both the normative exponential and descriptive hyperbolic discounting models, which agree on the additive assumption and the independence assumption. We also exculde the integration explanation which assumes subjects integrate upfront money with final rewards and make a decision with bottom line at the end. We consider several possible explanations, including the salience hypothesis, which states that introducing upfront money makes the money dimension more salient than not and thus increases the attractiveness of LL options.
The subduction model of the Neo-Tethys during the Early Cretaceous has always been a controversial topic, and the scarcity of Early Cretaceous magmatic rocks in the southern part of the Gangdese batholith is the main cause of this debate. To address this issue, this article presents new zircon U–Pb chronology, zircon Hf isotope, whole-rock geochemistry and Sr–Nd isotope data for the Early Cretaceous quartz diorite dykes with adakite affinity in Liuqiong, Gongga. Zircon U–Pb dating of three samples yielded ages of c. 141–137 Ma, indicating that the Liuqiong quartz diorite was emplaced in the Early Cretaceous. The whole-rock geochemical analysis shows that the Liuqiong quartz diorite is enriched in large-ion lithophile elements (LILEs) and light rare-earth elements (LREEs) and is depleted in high-field-strength elements (HFSEs), which are related to slab subduction. Additionally, the Liuqiong quartz diorite has high SiO2, Al2O3 and Sr contents, high Sr/Y ratios and low heavy rare-earth element (HREE) and Y contents, which are compatible with typical adakite signatures. The initial 87Sr/86Sr values of the Liuqiong adakite range from 0.705617 to 0.705853, and the whole-rock ϵNd(t) values vary between +5.78 and +6.24. The zircon ϵHf(t) values vary from +11.5 to +16.4. Our results show that the Liuqiong adakite magma was derived from partial melting of the Neo-Tethyan oceanic plate (mid-ocean ridge basalt (MORB) + sediment + fluid), with some degree of subsequent peridotite interaction within the overlying mantle wedge. Combining regional data, we favour the interpretation that the Neo-Tethyan oceanic crust was subducted at a low angle beneath the Gangdese during the Early Cretaceous.
Resistant starch (RS) has received increased attention due to its potential health benefits. This study was aimed to investigate the effects of dietary corn RS on immunological characteristics of broilers. A total of 320 broiler chicks were randomly allocated to five dietary treatments: normal corn–soyabean (NC) diet group, corn starch diet group, 4 %, 8 % and 12 % RS diet groups. This trial lasted for 42 d. The relative weights of spleen, thymus and bursa, the concentrations of nitric oxide (NO) and IL-4 in plasma at 21 d of age, as well as the activities of total nitric oxide synthase (TNOS) and inducible nitric oxide synthase (iNOS) in plasma at 21 and 42 d of age showed positive linear responses (P < 0·05) to the increasing dietary RS level. Meanwhile, compared with the birds from the NC group at 21 d of age, birds fed 4 % RS, 8 % RS and 12 % RS diets exhibited higher (P < 0·05) relative weight of bursa and concentrations of NO and interferon-γ in plasma. Birds fed 4 % RS and 8 % RS diets showed higher (P < 0·05) number of IgA-producing cells in the jejunum. While compared with birds from the NC group at 42 d of age, birds fed 12 % RS diet showed higher (P < 0·05) relative weight of spleen and activities of TNOS and iNOS in plasma. These findings suggested that dietary corn RS supplementation can improve immune function in broilers.
Metabolically healthy obesity (MHO) might be an alternative valuable target in obesity treatment. We aimed to assess whether alternative Mediterranean (aMED) diet and Dietary Approaches to Stop Hypertension (DASH) diet were favourably associated with obesity and MHO phenotype in a Chinese multi-ethnic population. We conducted this cross-sectional analysis using the baseline data of the China Multi-Ethnic Cohort study that enrolled 99 556 participants from seven diverse ethnic groups. Participants with self-reported cardiometabolic diseases were excluded to eliminate possible reverse causality. Marginal structural logistic models were used to estimate the associations, with confounders determined by directed acyclic graph (DAG). Among 65 699 included participants, 11·2 % were with obesity. MHO phenotype was present in 5·7 % of total population and 52·7 % of population with obesity. Compared with the lowest quintile, the highest quintile of DASH diet score had 23 % decreased odds of obesity (OR = 0·77, 95 % CI 0·71, 0·83, Ptrend < 0·001) and 27 % increased odds of MHO (OR = 1·27, 95 % CI 1·10, 1·48, Ptrend = 0·001) in population with obesity. However, aMED diet showed no obvious favourable associations. Further adjusting for BMI did not change the associations between diet scores and MHO. Results were robust to various sensitivity analyses. In conclusion, DASH diet rather than aMED diet is associated with reduced risk of obesity and presents BMI-independent metabolic benefits in this large population-based study. Recommendation for adhering to DASH diet may benefit the prevention of obesity and related metabolic disorders in Chinese population.
Bile acids (BA) have emerged as signalling molecules regulating intestinal physiology. The importance of intestinal microbiota in production of secondary BA, for example, lithocholic acid (LCA) which impairs enterocyte proliferation and permeability, triggered us to determine the effects of oral probiotics on intestinal BA metabolism. Piglets were weaned at 28 d of age and allocated into control (CON, n 14) or probiotic (PRO, n 14) group fed 50 mg of Lactobacillus plantarum daily, and gut microbiota and BA profile were determined. To test the potential interaction of LCA with bacteria endotoxins in inducing damage of enterocytes, IPEC-J2 cells were treated with LCA, lipopolysaccharide (LPS) and LCA + LPS and expressions of genes related to inflammation, antioxidant capacity and nutrient transport were determined. Compared with the CON group, the PRO group showed lower total LCA level in the ileum and higher relative abundance of the Lactobacillus genus in faeces. In contrast, the relative abundances of Bacteroides, Clostridium_sensu_stricto_1, Parabacteroides and Ruminococcus_1, important bacteria genera in BA biotransformation, were all lower in the PRO than in the CON group. Moreover, PRO piglets had lower postprandial glucagon-like peptide-1 level, while higher glucose level than CON piglets. Co-administration of LPS and LCA led to down-regulated expression of glucose and peptide transporter genes in IPEC-J2 cells. Altogether, oral L. plantarum altered BA profile probably by modulating relative abundances of gut microbial genera that play key roles in BA metabolism and might consequently impact glucose homoeostasis. The detrimental effect of LCA on nutrient transport in enterocytes might be aggravated under LPS challenge.
To explore the association between dietary Na intake and non-alcoholic fatty liver disease (NAFLD) in a nationally representative sample of the US population.
Design:
In this cross-sectional study, the associations between Na intake and NAFLD, defined by the hepatic steatosis index (HSI) and the fatty liver index (FLI), were assessed through multivariable logistic regression models.
Setting:
Communities in the USA from 2007 to 2014.
Participants:
Men and women aged 20 years and older.
Results:
A total of 11 022 participants were included in the HSI-defined NAFLD analysis, and a subsample of 5320 participants was included in the FLI-defined NAFLD analysis. Compared with the lowest quartile of Na intake, the highest quartile had a multivariate-adjusted OR and 95 % CI of 1·46 (1·29, 1·65) for NAFLD as defined by HSI, and 1·41 (1·18, 1·69) for NAFLD as defined by FLI. This association was, to some degree, attenuated but remained significant after adjusting for several related metabolic parameters, including BMI, hypertension, hypercholesterolaemia, and diabetes.
Conclusions:
Findings from the current study indicate that dietary Na intake is positively associated with NAFLD in US adults.
Pinewood nematode, Bursaphelenchus xylophilus, a pine parasitic nematode, poses a serious threat to its host pine forests globally. When dispersal-stage larvae 4 (dauer, DL4) of B. xylophilus enters the new pine, it moults into propagative adult (dauer recovery) and reproduces quickly to kill the host pine. Here, we found pine chemical volatiles, rather than the common dauer recovery factors of nematodes (e.g. suitable temperatures, nutrient availability or density), promote B. xylophilus dauer recovery. The results showed that volatilization of chemicals in host pines could attract DL4 and promote DL4 recovery. To identify which chemicals promote this process, we determined the stimulated activity of the main volatiles of pines including six monoterpenes and two sesquiterpenes. Results showed that all the six monoterpenes promoted dauer recovery, especially β-pinene and β-myrcene, but the two sesquiterpenes have no effect on the transformation. Furthermore, β-pinene performed gradient effects on dauer recovery. We hypothesized that when DL4 infect pine trees, the pine volatiles released from the feeding wounds are used as chemical signals for DL4 transformation to adult to reproduce and rapidly kill the pines. Our study identified the B. xylophilus dauer recovery chemical signal and may contribute to preventing pine wilt disease.
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.
We study numerically the dynamics of an insoluble surfactant-laden droplet in a simple shear flow taking surface viscosity into account. The rheology of drop surface is modelled via a Boussinesq–Scriven constitutive law with both surface tension and surface viscosity depending strongly on the surface concentration of the surfactant. Our results show that the surface viscosity exhibits non-trivial effects on the surfactant transport on the deforming drop surface. Specifically, both dilatational and shear surface viscosity tend to eliminate the non-uniformity of surfactant concentration over the drop surface. However, their underlying mechanisms are entirely different; that is, the shear surface viscosity inhibits local convection due to its suppression on drop surface motion, while the dilatational surface viscosity inhibits local dilution due to its suppression on local surface dilatation. By comparing with previous studies of droplets with surface viscosity but with no surfactant transport, we find that the coupling between surface viscosity and surfactant transport induces non-negligible deviations in the dynamics of the whole droplet. More particularly, we demonstrate that the dependence of surface viscosity on local surfactant concentration has remarkable influences on the drop deformation. Besides, we analyse the full three-dimensional shape of surfactant-laden droplets in simple shear flow and observe that the drop shape can be approximated as an ellipsoid. More importantly, this ellipsoidal shape can be described by a standard ellipsoidal equation with only one unknown owing to the finding of an unexpected relationship among the drop’s three principal axes. Moreover, this relationship remains the same for both clean and surfactant-laden droplets with or without surface viscosity.
Human papillomavirus (HPV) has been identified as etiologic agent of various cancers for both men and women. However, HPV vaccine has not been recommended for men in China by far. To provide more evidences to promote HPV vaccination among males at high-risk of infection, this study investigated genital HPV genotypes among male attendees of sexually transmitted disease (STD) clinic. Male attendees (⩾18 years old) were recruited from STD clinic of Beijing Ditan Hospital. Data on sociodemographic characteristics and self-reported sexual behaviors were collected based on questionnaire. Genital swab specimens were collected for HPV genotypes. Finally, a total of 198 eligible participants were included in the study. Nearly half of them were infected with at least one type of HPV. The prevalence of genital infection among participants with only heterosexual behaviors (50·91%, 56/110) was significantly higher than those with only homosexual behaviors (36·36%, 32/88) (P < 0·001). However, the distribution pattern of the most frequently observed HPV subtypes were found to be similar between these two subgroups. HPV31, HPV18, HPV16 and HPV58 were the most frequently identified high-risk types and HPV11, HPV6, HPV81 and HPV61 were the most frequently observed low-risk types. Our results, although need further verification by larger sample size, suggested that currently available HPV vaccines covered most prevalent HPV types observed in Chinese men. As HPV vaccine has been approved for application in females in China, molecular epidemiological studies and intervention studies among high-risk males should be promoted as well.
Excavation of the Han Dynasty chambered tomb at Laoguanshan in Chengdu, south-west China, has provided the earliest known evidence of pattern loom technology. Four model looms, along with accompanying artefacts and figurines relating to the weaving process, give insight into the technique of jin silk production. The discovery is hugely significant as it provides the first direct evidence of pattern-weave textile production in ancient China. Jin silk, made using this method, was both valuable and widely distributed, and the design of the machine influenced the invention of later looms and the spread of technology throughout Eurasia and Europe, representing great technological accomplishment for the second century BC.
Crofton weed is a noxious invasive weed worldwide. However, the mechanisms underlying its invasiveness are still not well understood. We hypothesize that genetic differentiation and plasticity may help the plant invade heterogeneous habitats. To test this hypothesis, we compared the differences in seed morphometric and germination traits among 14 populations of the plant located at different elevations (640–2,430 m) in south Yunnan Province of southwest China. Germination capacity (GC) and index (GI) were markedly different among the 14 populations at the same temperature or water treatment. The results indicated genetic differentiations in these traits; maternal effects were not excluded. GC and GI were also different for each population across temperature or water treatments, showing phenotypic plasticity. Croton weed seed size and weight also responded genetically or plastically (or both) to different elevations. Seed width, weight, GC, and GI at each temperature increased with the increase of the elevation of origin, showing clinal variation patterns that reveal local adaptations to habitats encountered by the plant. The large seeds, high GC, and high GI could improve emergence, establishment, growth, and survival of seedlings at high elevation; the low GI could prevent seed germination before the onset of the rainy season at low elevation. On the basis of the results, genetic differentiation and plasticity in seed size and germination traits may help crofton weed acclimate to different elevations, facilitating its invasiveness.
Beginning in 2007, all newly diagnosed cancer patients at the Koo Foundation Sun Yat-Sen Cancer Center (KF–SYSCC) were screened for psychosocial distress. Our social workers, as part of the psychosocial care team (PCT), have engaged in proactive outreach with patients identified as distressed. The goal of the present study was to assess the prevalence of psychosocial distress and the extent of contact between the PCT and distressed patients.
Method:
Newly diagnosed patients who were treated at KF–SYSCC between 2007 and 2010 for cancer were eligible if there were at least 100 patients with the same type of cancer. Before treatment began, they were screened with the Pain Scale and the Distress Thermometer (DT) and had the option to specify a desire for help. The rates of distress were analyzed by cancer type and by probable related factors. Information regarding contact with the PCT was retrieved from computerized databases.
Results:
Overall, some 5,335 cancer patients representing 12 major cancer types were included in our study. Of these, 1,771 (33.20%) were significantly distressed. By multivariate logistic regression, younger age, female gender, higher pain score, and disease stage, but not cancer type, were found to be associated with higher rates of distress. Among these distressed patients, 628 (36%) had some contact with the PCT.
Significance of results:
This Taiwanese study with a large sample size revealed a prevalence rate of psychosocial distress similar to rates found in Western countries. Contact with the PCT was established in only 36% of significantly distressed patients, despite a proactive outreach program. It is very important to have screening results made available in a timely fashion to the psycho-oncology team so that appropriate care can be offered promptly.
The objective of this study was to build a database to collect infectious disease information at the scene of a disaster through the use of 128 epidemiological questionnaires and 47 types of options, with rapid acquisition of information regarding infectious disease and rapid questionnaire customization at the scene of disaster relief by use of a personal digital assistant (PDA).
Methods
SQL Server 2005 (Microsoft Corp, Redmond, WA) was used to create the option database for the infectious disease investigation, to develop a client application for the PDA, and to deploy the application on the server side. The users accessed the server for data collection and questionnaire customization with the PDA.
Results
A database with a set of comprehensive options was created and an application system was developed for the Android operating system (Google Inc, Mountain View, CA). On this basis, an infectious disease information collection system was built for use at the scene of disaster relief. The creation of an infectious disease information collection system and rapid questionnaire customization through the use of a PDA was achieved.
Conclusions
This system integrated computer technology and mobile communication technology to develop an infectious disease information collection system and to allow for rapid questionnaire customization at the scene of disaster relief. (Disaster Med Public Health Preparedness. 2017;11:668–673)
Mussels are typical macrofouling organisms in the world. In this study, the interaction between the settlement of Mytilus coruscus plantigrades and bacterial community on coloured substrata was determined. Bacterial communities in biofilms developed on seven coloured substrata were analysed by Illumina Miseq sequencing. The mussel settlement response to coloured substrata with no biofilms was also examined. Flavobacteria, Alphaproteobacteria and Gammaproteobacteria were the first, second and third most dominant groups in seven biofilm samples. The results suggest that the inducing activities of these biofilms on plantigrade settlement varied with coloured substrata and the lowest percentage of settlement was observed on biofilms on the green substratum. High-throughput sequencing showed that bacterial community in biofilms also changed with the substratum colour. No significant difference in the inducing activity on plantigrade settlement was observed between the coloured substrata with no biofilms. Thus, difference in plantigrade settlement response may be correlated to the changes in bacterial community on coloured substrata. This finding extends current knowledge of interaction among mussel settlement and bacterial community variability.
The microstructural evolution of spray-formed high speed steel during hot deformation was investigated as well as the effects of spray forming parameters on the porosity formation. Four distinct zones are identified in the as-deposited material, and interstitial porosity is present in the bottom and peripheral zones, while gas-related porosity is mainly found in the central zone. It can keep the porosity at a minimum value by using the optimum parameters, e.g., the average porosity of central zone is 3.7% for a superheat of 170 °C and a gas-to-metal flow rate of 0.7. During hot deformation at 1150 °C, the amount of porosity can be obviously decreased by increasing the height reduction which also plays a key role in breaking up eutectic carbides. The critical height reduction for the breakdown of the eutectic carbides is 50%, the dominant mechanism being mechanical fragmentation.
This study modified the surfaces of three kinds of TiNi-based shape memory alloys (SMAs) by dry electrical discharge machining (EDM) in nitrogen (N2) and acetylene (C2H2) gas mixture. The effects of composition of the dielectric medium and work-piece on the machining performance and surface characteristics were investigated. Increasing the ratio of acetylene gas in gas mixture was beneficial for improving the material removal rate (MRR). However, adding a large amount of acetylene gas resulted in unstable discharge. A recast layer, comprising nitrides and carbides, which well adhered on the EDMed surface exhibited high hardness. Among Ti50Ni50, Ti50Ni49.5Cr0.5, and Ti40.5Ni49.5Zr10 SMA as a work-piece, Ti40.5Ni49.5Zr10 SMA has the lowest MRR owing to it possessed the highest melting temperature and thermal conductivity. The recast layer on Ti40.5Ni49.5Zr10 SMA, comprising zirconium nitride, exhibited the highest hardness and adhesion among all the SMAs. However, the high-hardness recast layer deteriorated the shape recovery of the SMA.
The present study was conducted to investigate the anti-inflammatory effect of vitamin D both in juvenile Jian carp (Cyprinus carpio var. Jian) in vivo and in enterocytes in vitro. In primary enterocytes, exposure to 10 mg lipopolysaccharide (LPS)/l increased lactate dehydrogenase activity in the culture medium (P<0·05) and resulted in a significant loss of cell viability (P<0·05). LPS exposure increased (P<0·05) the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8), which was decreased by pre-treatment with 1,25-dihydroxyvitamin D (1,25D3) in a dose-dependent manner (P<0·05). Further results showed that pre-treatment with 1,25D3 down-regulated Toll-like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (Myd88) and NF-κB p65 mRNA expression (P<0·05), suggesting potential mechanisms against LPS-induced inflammatory response. In vivo, intraperitoneal injection of LPS significantly increased TNF-α, IL-1β, IL-6 and IL-8 mRNA expression in the intestine of carp (P<0·05). Pre-treatment of fish with vitamin D3 protected the fish intestine from the LPS-induced increase of TNF-α, IL-1β, IL-6 and IL-8 mainly by downregulating TLR4, Myd88 and NF-κB p65 mRNA expression (P<0·05). These observations suggest that vitamin D could inhibit LPS-induced inflammatory response in juvenile Jian carp in vivo and in enterocytes in vitro. The anti-inflammatory effect of vitamin D is mediated at least in part by TLR4-Myd88 signalling pathways in the intestine and enterocytes of juvenile Jian carp.
The deformation of a compound capsule (an elastic capsule with a smaller capsule inside) in simple shear flow is studied by using three-dimensional numerical simulations based on a front tracking method. The inner and outer capsules are concentric and initially spherical. Skalak et al.’s constitutive law is employed for the mechanics of both the inner and outer membranes. Our results concerning the deformation of homogeneous capsules (i.e. capsules without the inner capsules) are quantitatively in agreement with the predictions of previous numerical simulations and perturbation theories. Compared to homogeneous capsules, compound capsules exhibit smaller deformation. The deformations of both the inner and outer capsules are significantly affected by the capillary numbers of the inner and outer membranes and the volume ratio of the inner to the outer capsule. When the inner capsule is small, it presents smaller deformation than the outer capsule. However, when the inner capsule is sufficiently large, it can present larger deformation than the outer capsule, even if the inner membrane has much lower capillary number than the outer membrane. The underlying mechanisms are discussed: (i) the inner capsule is deformed by rotational flow with lower rate of strain rather than by simple shear flow that deforms the outer capsule, and thus the inner capsule exhibits smaller deformation; and (ii) when the inner and outer membranes are sufficiently close (i.e. the inner capsule is sufficiently large), the hydrodynamic interaction between the two membranes becomes significant, which is found to inhibit the deformation of the outer capsule but to promote the deformation of the inner capsule.