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Constraining the timing and extent of Quaternary glaciations in the Tibetan Plateau (TP) is significant for the reconstruction of paleoclimatic environment and understanding the interrelationships among climate, tectonics, and glacial systems. We investigated the late Quaternary glacial history of the Qinggulong and Juequ valleys in the Taniantaweng Mountains, southeastern TP, using cosmogenic 10Be surface exposure dating. Four major glacial events were identified based on 26 10Be ages. The exposure ages of the oldest late Quaternary glaciation correspond to Marine Oxygen Isotope Stage (MIS) 6. The maximum glacial extent was dated to 48.5–41.1 ka (MIS 3), during the last glaciation, and was more advanced than that of the last glacial maximum (LGM). Geochronology and geomorphological evidence indicate that multiple glacial fluctuations occurred in the study area during the Early–Middle Holocene. These glacial fluctuations likely were driven by the North Atlantic climate oscillations, summer solar insolation variability, Asian summer monsoon intensity, and CO2 concentration.
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.
The 4.2 ka event is widely presumed to be a globally widespread aridity event and has been linked to several episodes of societal changes across the globe. Whether this climate event impacted the cultural development in south-central China remains uncertain due to a lack of regional paleorainfall records. We present here stalagmite stable carbon isotope and trace element–based reconstruction of hydroclimatic conditions from south-central China. Our data reveal a sub–millennial scale (~5.6 to 4.3 ka) drying trend in the region followed by a gradual transition to wetter conditions during the 4.2 ka event (4.3–3.9 ka). Together with the existing archaeological evidence, our data suggest that the drier climate before 4.3 ka may have promoted the Shijiahe culture, while the pluvial conditions during the 4.2 ka event may have adversely affected its settlements in low-lying areas. While military conflicts with the Wangwan III culture may have accelerated the collapse of Shijiahe culture, we suggest that the joint effects of climate and the region's topography also played important causal roles in its demise.
As past usual diet quality may affect gut microbiome (GM) composition, we examined the association of the Healthy Eating Index (HEI)-2015 assessed 21 and 9 years before stool collection with measures of fecal microbial composition in a subset of the Multiethnic Cohort. A total of 5936 participants completed a validated quantitative FFQ (QFFQ) at cohort entry (Q1, 1993–1996), 5280 at follow-up (Q3, 2003–2008) and 1685 also at a second follow-up (Adiposity Phenotype Study (APS), 2013–2016). All participants provided a stool sample in 2013–2016. Fecal microbial composition was obtained from 16S rRNA gene sequencing (V1–V3 regions). HEI-2015 scores were computed based on each QFFQ. Using linear regression adjusted for relevant covariates, we calculated associations of HEI-2015 scores with gut microbial diversity and 152 individual genera. The mean HEI-2015 scores increased from Q1 (67 (sd 10)) to Q3 (71 (sd 11)) and APS (72 (sd 10)). Alpha diversity assessed by the Shannon Index was significantly higher with increasing tertiles of HEI-2015. Of the 152 bacterial genera tested, seven (Anaerostipes, Coprococcus_2, Eubacterium eligens, Lachnospira, Lachnospiraceae_ND3007, Ruminococcaceae_UCG-013 and Ruminococcus_1) were positively and five (Collinsella, Parabacteroides, Ruminiclostridium_5, Ruminococcus gnavus and Tyzzerella) were inversely associated with HEI-2015 assessed in Q1, Q3 and APS. The estimates of change per unit of the HEI-2015 score associated with the abundance of these twelve genera were consistent across the three questionnaires. The quality of past diet, assessed as far as ∼20 years before stool collection, is equally predictive of GM composition as concurrently assessed diet, indicative of the long-term consistency of this relation.
Through laboratory experiments and numerical simulations, we examine the evolution of buoyant plumes as they are influenced by background rotation in a uniform density ambient fluid. The source Rossby number is sufficiently large that rotation does not directly affect the plume at early times. However, on a time scale of the order of half a rotation period, the plume becomes deflected from the vertical axis. For some experiments and simulations, the deflection persists and the flow precesses about the vertical axis. In other cases, shortly after being deflected, the plume laminarizes near the source to form a near-vertical columnar vortex, which we refer to as a ‘tornado’. Tornado formation occurs in some experiments and not in others even if the source and background rotation parameters are identical. However, their formation is more likely if the plumes are ‘lazy’. Simulations reveal that this is a consequence of the competing dynamics that occurs on comparable time scales. As a consequence of entrainment, vertical vorticity builds up within the plume reducing the Rossby number and suppressing vertical motion at distances progressively closer to the source. Meanwhile, the swirl (the ratio of the azimuthal to vertical flow) around the vicinity of the source increases, which tends to suppress three-dimensional turbulence in the near-source flow. Although the former process ultimately acts to deflect the plume off axis, in some instances, the swirl around the source succeeds in laminarizing the flow, resulting in tornado formation.
Non-typhoidal Salmonella (NTS) serovars, sequences types and antimicrobial susceptibility profiles have specific associations with animal and human infections in Vietnam. Antimicrobial resistance may have an effect on the manifestation of human NTS infections, with isolates from asymptomatic individuals being more susceptible to antimicrobials than those associated with animals and human diarrhoea.
Raw milk cheeses are commonly consumed in France and are also a common source of foodborne outbreaks (FBOs). Both an FBO surveillance system and a laboratory-based surveillance system aim to detect Salmonella outbreaks. In early August 2018, five familial FBOs due to Salmonella spp. were reported to a regional health authority. Investigation identified common exposure to a raw goats' milk cheese, from which Salmonella spp. were also isolated, leading to an international product recall. Three weeks later, on 22 August, a national increase in Salmonella Newport ST118 was detected through laboratory surveillance. Concomitantly isolates from the earlier familial clusters were confirmed as S. Newport ST118. Interviews with a selection of the laboratory-identified cases revealed exposure to the same cheese, including exposure to batches not included in the previous recall, leading to an expansion of the recall. The outbreak affected 153 cases, including six cases in Scotland. S. Newport was detected in the cheese and in the milk of one of the producer's goats. The difference in the two alerts generated by this outbreak highlight the timeliness of the FBO system and the precision of the laboratory-based surveillance system. It is also a reminder of the risks associated with raw milk cheeses.
Nutritional therapy is a cornerstone of burns management. The optimal macronutrient intake for wound healing after burn injury has not been identified, although high-energy, high-protein diets are favoured. The present study aimed to identify the optimal macronutrient intake for burn wound healing. The geometric framework (GF) was used to analyse wound healing after a 10 % total body surface area contact burn in mice ad libitum fed one of the eleven high-energy diets, varying in macronutrient composition with protein (P5−60 %), carbohydrate (C20−75 %) and fat (F20−75 %). In the GF study, the optimal ratio for wound healing was identified as a moderate-protein, high-carbohydrate diet with a protein:carbohydrate:fat (P:C:F) ratio of 1:4:2. High carbohydrate intake was associated with lower mortality, improved body weight and a beneficial pattern of body fat reserves. Protein intake was essential to prevent weight loss and mortality, but a protein intake target of about 7 kJ/d (about 15 % of energy intake) was identified, above which no further benefit was gained. High protein intake was associated with delayed wound healing and increased liver and spleen weight. As the GF study demonstrated that an initial very high protein intake prevented mortality, a very high-protein, moderate-carbohydrate diet (P40:C42:F18) was specifically designed. The dynamic diet study was also designed to combine and validate the benefits of an initial very high protein intake for mortality, and subsequent moderate protein, high carbohydrate intake for optimal wound healing. The dynamic feeding experiment showed switching from an initial very high-protein diet to the optimal moderate-protein, high-carbohydrate diet accelerated wound healing whilst preventing mortality and liver enlargement.
This study aimed to examine the efficacy of combining paroxetine and mirtazapine v. switching to mirtazapine, for patients with major depressive disorder (MDD) who have had an insufficient response to SSRI monotherapy (paroxetine) after the first 2 weeks of treatment.
This double-blind, randomized, placebo-controlled, three-arm study recruited participants from five hospitals in China. Eligible participants were aged 18–60 years with MDD of at least moderate severity. Participants received paroxetine during a 2-week open-label phase and patients who had not achieved early improvement were randomized to paroxetine, mirtazapine or paroxetine combined with mirtazapine for 6 weeks. The primary outcome was improvement on the Hamilton Rating Scale for Depression 17-item (HAMD-17) scores 6 weeks after randomization.
A total of 204 patients who showed early non-response to paroxetine monotherapy were randomly assigned to receive either mirtazapine and placebo (n = 68), paroxetine and placebo (n = 68) or mirtazapine and paroxetine (n = 68), with 164 patients completing the outcome assessment. At week 8, the least squares (LS) mean change of HAMD-17 scores did not significantly differ among the three groups, (12.98 points) in the mirtazapine group, (12.50 points) in the paroxetine group and (13.27 points) in the mirtazapine plus paroxetine combination group. Participants in the paroxetine monotherapy group were least likely to experience adverse effects.
After 8 weeks follow-up, paroxetine monotherapy, mirtazapine monotherapy and paroxetine/mirtazapine combination therapy were equally effective in non-improvers at 2 weeks. The results of this trial do not support a recommendation to routinely offer additional treatment or a switch in treatment strategies for MDD patients who do not show early improvement after 2 weeks of antidepressant treatment.
Prior data on long-term association between legume consumption and hypertension risk are sparse. We aimed to evaluate whether total legume and subtype intakes prospectively associate with hypertension incidence among 8758 participants (≥30 years) from the China Health and Nutrition Survey 2004–2011. Diet was assessed by interviews combining 3-d 24-h food recalls and household food inventory weighing at each survey round. Incident hypertension was identified by self-reports or blood pressure measurements. We applied multivariable Cox regressions to estimate hazard ratios (HR) with corresponding 95 % CI for hypertension across increasing categories of cumulatively averaged legume intakes. For 35 990 person-years (median 6·0 years apiece), we documented 944 hypertension cases. After covariate adjustment, higher total legume intakes were significantly associated with lower hypertension risks, with HR comparing extreme categories being 0·56 (95 % CI 0·43, 0·71; Ptrend < 0·001). Then we found that intakes of dried legumes (HR 0·53 (95 % CI 0·43, 0·65); Ptrend < 0·001) and fresh legumes (HR 0·67 (95 % CI 0·55, 0·81); Ptrend < 0·001) were both related to decreased hypertension hazards. However, further dried legume classification revealed that negative association with hypertension substantially held for soyabean (HR 0·51 (95 % CI 0·41, 0·62); Ptrend < 0·001) but not non-soyabean intakes. In stratified analyses, the association of interest remained similar within strata by sex, BMI, physical activity, smoking and drinking status; rather, significant heterogeneity showed across age strata (Pinteraction = 0·02). Total legume consumption among the over-65s was related to a more markedly reduced hypertension risk (HR 0·47 (95 % CI 0·30, 0·73); Ptrend < 0·001). Our findings suggest an inverse association of all kinds of legume (except non-soyabean) intakes with hypertension risks.
The cao vit gibbon Nomascus nasutus, also known as eastern black crested gibbon, is categorized as Critically Endangered on the IUCN Red List and was considered one of the world's 25 most threatened primates. The only known population occurs along the border between China and Viet Nam. Accurate information on population size and dynamics is critical for the species’ conservation, but population surveys conducted in only one country may over- or underestimate total population size because the home ranges of cao vit gibbon groups often cross the international border. In 2007 and 2016 we conducted two collaborative transboundary censuses of the cao vit gibbon populations in the Trung Khanh Cao Vit Gibbon Species and Habitat Conservation Area in Viet Nam and the Bangliang Gibbon National Nature Reserve in China. The results showed a population size of 102–110 in 2007, which increased to 107–136 in 2016. Our results indicate that previous surveys conducted separately in Viet Nam and China underestimated the global population size of this species. According to our more comprehensive surveys, the gibbon population is increasing slowly. The gibbons and their habitat are legally protected in both countries. Hunting and charcoal making have not been reported in this area since 2007. As habitat carrying capacity is a limiting factor, habitat restoration is required. However, lack of funding to protect the cao vit gibbon remains a challenge.
The effect of nitrogen gas addition in Ar-based double-layer shielding gas on the impact toughness of welded ultra-ferritic stainless steel during an autogenous gas tungsten arc welding (GTAW) process was investigated. The nitrogen behavior was proposed. The microstructure, mechanical properties, and fracture surface morphology of the weld metals have been evaluated. More equiaxed crystals, refined grain, narrow HAZ width, and increased microhardness were produced with nitrogen addition. Experimental findings indicated that nitrogen diffused into HAZ and dissolved into weld pool. The solute distribution was changed thus bringing significant constitutional supercooling and decreased temperature gradient of weld pool, which contributed to fine microstructure. Impact toughness at room temperature was enhanced from 2J to 9J (welds), 5J–13J (HAZ). Ductile fracture zone was produced about 0.3–0.5 mm thickness distance from the weld surface. A significant increased impact toughness of weld metal was due to the refinement of microstructure and element addition.
There is an increasing interest in using logic programming to specify and implement distributed algorithms, including a variety of network applications. These are applications where data and computation are distributed among several devices and where, in principle, all the devices can exchange data and share the computational results of the group. In this paper we propose a declarative approach to distributed computing whereby distributed algorithms and communication models can be (i) specified as action theories of fluents and actions; (ii) executed as collections of distributed state machines, where devices are abstracted as (input/output) automata that can exchange messages; and (iii) analysed using existing results on connecting causal theories and Answer Set Programming. Results on the application of our approach to different classes of network protocols are also presented.
In Vietnam, highly pathogenic avian influenza (HPAI) H5N1 infections in poultry often occur without concomitant clinical signs and outbreaks are not consistently reported. Live bird markets represent a convenient site for surveillance that does not rely on farmers' notifications. Two H5N1 surveys were conducted at live bird markets/slaughter points in 39 districts (five provinces) in the Red River, Mekong delta, and central Vietnam during January and May 2011. Oropharyngeal and rectal swab samples from 12 480 ducks were tested for H5N1 by reverse transcription–polymerase chain reaction in pools of five. Traders and stallholders were interviewed using standardized questionnaires; 3·3% of pools tested positive. The highest prevalence (6·6%) corresponded to the Mekong delta, and no H5N1 was detected in the two Red River provinces. The surveys identified key risk behaviours of traders and stallholders. It is recommended that market surveys are implemented over time as a tool to evaluate progress in HPAI control in Vietnam.
Lutein and zeaxanthin are thought to decrease the incidence of age-related macular degeneration (AMD); however, findings have been inconsistent. We conducted a systematic literature review and meta-analysis to evaluate the relationship between dietary intake of lutein and zeaxanthin and AMD risk. Relevant studies were identified by searching five databases up to April 2010. Reference lists of articles were retrieved, and experts were contacted. Literature search, data extraction and study quality assessment were performed independently by two reviewers and results were pooled quantitatively using meta-analysis methods. The potential sources of heterogeneity and publication bias were also estimated. The search yielded six longitudinal cohort studies. The pooled relative risk (RR) for early AMD, comparing the highest with the lowest category of lutein and zeaxanthin intake, was 0·96 (95 % CI 0·78, 1·17). Dietary intake of these carotenoids was significantly related with a reduction in risk of late AMD (RR 0·74; 95 % CI 0·57, 0·97); and a statistically significant inverse association was observed between lutein and zeaxanthin intake and neovascular AMD risk (RR 0·68; 95 % CI 0·51, 0·92). The results were essentially consistent among subgroups stratified by participant characteristics. The findings of the present meta-analysis indicate that dietary lutein and zeaxanthin is not significantly associated with a reduced risk of early AMD, whereas an increase in the intake of these carotenoids may be protective against late AMD. However, additional studies are needed to confirm these relationships.
We aimed to examine the effect of different doses of lutein supplementation on visual function in subjects with long-term computer display light exposure. Thirty-seven healthy subjects with long-term computer display light exposure ranging in age from 22 to 30 years were randomly assigned to one of three groups: Group L6 (6 mg lutein/d, n 12); Group L12 (12 mg lutein/d, n 13); and Group Placebo (maltodextrin placebo, n 12). Levels of serum lutein and visual performance indices such as visual acuity, contrast sensitivity and glare sensitivity were measured at weeks 0 and 12. After 12-week lutein supplementation, serum lutein concentrations of Groups L6 and L12 increased from 0·356 (sd 0·117) to 0·607 (sd 0·176) μmol/l, and from 0·328 (sd 0·120) to 0·733 (sd 0·354) μmol/l, respectively. No statistical changes from baseline were observed in uncorrected visual acuity and best-spectacle corrected visual acuity, whereas there was a trend toward increase in visual acuity in Group L12. Contrast sensitivity in Groups L6 and L12 increased with supplementation, and statistical significance was reached at most visual angles of Group L12. No significant change was observed in glare sensitivity over time. Visual function in healthy subjects who received the lutein supplement improved, especially in contrast sensitivity, suggesting that a higher intake of lutein may have beneficial effects on the visual performance.