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Environment can impact the wear behavior of metals and alloys substantially. The tribological properties of Al0.6CoCrFeNi high-entropy alloys (HEAs) were investigated in ambient air, deionized water, simulated acid rain, and simulated seawater conditions at frequencies of 2–5 Hz. The as-cast alloy was composed of simple face-centered cubic and body-centered cubic phases. The wear rate of the as-cast HEA in the ambient air condition was significantly higher than that in the liquid environment. The wear resistance in seawater was superior to that in ambient air, deionized water, and acid rain. Both the friction coefficient and wear rate in seawater were the lowest due to the formation of oxidation film, lubrication, and corrosion action in solution. The dominant wear mechanism in the ambient air condition and deionized water was abrasive wear, delamination wear, and oxidative wear. By contrast, the wear mechanism in acid rain and seawater was mainly corrosion wear, adhesive wear, abrasive wear, and oxidative wear.
Dietary intake is a leading risk factor for hypertension. We aimed to assess longitudinal associations between overall dietary patterns and incident hypertension among adults in Thailand.
Prospective large Thai Cohort Study (TCS) conducted nationwide from 2005 to 2013. Dietary patterns were identified using factor analysis based on usual intake of fourteen food groups. Multivariable logistic regression assessed associations between dietary patterns and hypertension prevalence and incidence.
Emerging hypertension and changing diets in Thailand.
TCS participants who were normotensive at baseline in 2005.
Among 36293 participants without hypertension at baseline, 1831 reported incident hypertension (5·1 % incidence) at follow-up. Two dietary patterns were identified: ‘Modern’ and ‘Prudent’. The Modern dietary pattern (high intakes of roasted/smoked foods, instant foods, canned foods, fermented fruits/vegetables, fermented foods, soft drinks, deep-fried foods) was associated with increased incident hypertension (comparing extreme quartiles, OR for incident hypertension=1·51; 95 % CI 1·31, 1·75 in 2013). The Prudent dietary pattern (high intakes of soyabean products, milk, fruits, vegetables) was not associated with incident hypertension in a fully adjusted model. The association between the Modern dietary pattern and hypertension was attenuated by BMI.
Modern dietary pattern was positively associated with hypertension among Thai adults. BMI had a great impact on the relationship between the Modern dietary pattern and incidence of hypertension. Reduction of Modern diets would be expected to prevent and control hypertension. Such a strategy would be worth testing.
Background: With advancements in technology, the use of video as a pedagogical method in medical education has gained in popularity, and may aid in teaching clinical skills. In the UBC MD program, videos have been used to assist in teaching the -neurological exam for several decades, but the currently available videos are outdated and not of contemporary quality. Methods: Drawing upon the cognitive theory of multimedia learning from Mayer and Moreno (2003) which describes methods to maximize learning by minimizing cognitive load, we developed a tool to systematically assess pedagogical videos. We inventoried twelve existing neurology videos and analyzed their use of methods such as weeding (removing extraneous information), signalling (visually highlighting important information), and chunking (grouping similar information together). Results: Generally, older videos had poor audiovisual quality that introduced extraneous load, while more current videos had higher production value, albeit inconsistent with the depth of their content. We therefore produced a new three-part neurological exam video series. We wrote storyboards, filmed with a focus on visually depicting the exam and findings, and edited to elucidate relevant physiological concepts. Conclusions: The end product has been adopted by the UBC MD program, and can be shared with other programs who may wish to adopt them.
Climate change has greatly affected agricultural production, and will lead to further changes in cropping system, varietal type and cultivation techniques for each region. The potential effects of climate change on rice production in Fujian Province, China, were explored in the current study with CERES-Rice model and climate-change scenarios, based on the self-adaptation of rice production. The results indicated that simulated yields of early rice in the double-rice region in south-eastern Fujian under scenarios A2, B2 and A1B increased by 15·9, 18·0 and 19·2%, respectively, and correspondingly those of late rice increased by 9·2, 7·4 and 7·4% when self-adaptation adjustment was considered, compared to scenarios without that consideration. In the double-rice region in north-western Fujian, simulated yields of early rice increased by 21·2, 20·5 and 18·9% and those of late rice by 14·7, 14·8 and 7·2% under scenarios A2, B2 and A1B, respectively, when self-adaptation was considered, compared to without consideration. Similar results were obtained for the single-rice region in the mountain areas of north-western Fujian, correspondingly increasing by 4·9, 5·0 and 2·9% when self-adaptation was considered compared to when it was not. In this single-rice region, double rice might be grown in the future at the Changting site under scenarios A1 and B2. When the self-adaptation adjustment was considered, the simulated overall output of rice crops in Fujian under scenarios A2, B2 and A1B increased by 5·9, 5·2 and 5·1%, respectively. Thus, more optimistic results were obtained when the self-adaptation ability of rice production was considered.
To investigate patterns of survival and estimate conditional survival rates among brain cancer patients in Canada. METHODS: Canadian Cancer Registry data were obtained for all patients with primary brain cancer diagnosed between 1992 and 2008 (n=38,095). Follow-up ended with patient death or December 31, 2008, whichever occurred first. Crude Kaplan-Meier estimates were calculated at one, two, and five years post-diagnosis and also used to estimate conditional survival (restricted to 2000-2008). Age group, sex, residence and microscopic confirmation were considered in estimating rates for major histology types using multivariate models. RESULTS: The overall five-year survival rate was 27%. Oligodendrogliomas had the highest 5-year survival rate (65%, 95% CI: 62.5-67.4%) and glioblastomas the lowest (4.0%, 95% CI: 3.7-4.3%). Compared to Ontario, the age- and sex-adjusted 5-year glioblastoma survival estimates were lower in British Columbia, Alberta and Manitoba-Saskatchewan, lower in all other regions for diffuse astrocytoma, and lower in Manitoba-Saskatchewan for anaplastic astrocytomas. Estimates were significantly higher for oligodendrogliomas in Alberta, and for anaplastic oligodendrogliomas in Alberta and Quebec (P<0.05). Longer term conditional survival rates (surviving an additional 2 years 1-4 years after diagnosis) varied by histologic group. CONCLUSION: There is a need to further explore the underlying reasons for the observed variation in survival rates by region in an effort to improve the prognosis of brain cancer in the Canadian patient population. Conditional survival information has value for clinicians as they plan the course of treatment and follow-up for individual patients.
Toxocariasis is a very prevalent zoonotic disease worldwide. Recently, investigators have focused more on Toxocara spp. seroprevalence in humans. Information regarding Toxocara seroprevalence in people from different ethnic backgrounds in China is limited. For this study, blood samples were collected from a total of 802 Han, 520 Korean, 303 Manchu, and 217 Mongol subjects from Jilin and Shandong provinces. The overall Toxocara seroprevalence was 16·07% (14·21% Han, 20·58% Korean, 11·22% Manchu, 18·89% Mongol). Living in suburban or rural areas, having dogs at home, exposure to soil, and consumption of raw/undercooked meat were risk factors for Toxocara infection. Exposure to soil was identified as the major risk factor for Toxocara seropositivity in all of the tested ethnicities. To the best of our knowledge, this is the first report concerning Toxocara infection in Manchus and Mongols in China. The present study provided baseline data for effective prevention strategies of toxocariasis in northeast China and recommends improvements in personal hygiene standards to achieve this goal.
Accelerator mass spectrometry (AMS) radiocarbon dating a continuous core from Lake Gun Nur, northern Mongolia, shows a period between 10 and 8 ka BP that could not be dated accurately. Further dating on alkali-insoluble residue and humic acid from the same samples in the Gun Nur core suggest that this AMS 14C date anomaly is neither analytical nor material related. We hypothesize that the 14C anomaly may be derived from increasing production rates of 14C caused by diminished solar activity, a low 14CO2/14CO ratio in the atmosphere, or an unstable 14C flux in the lower atmosphere caused by changing geomagnetic field strength. Our results imply that the 14C data used for 14C age calibration cannot correct the age-depth regression between 8 and 10 ka BP to fit the age-depth model along with other time intervals.
Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) is an important natural enemy of many species of lepidopterous pests and a widely used biological control agent. Detailed knowledge about its mate choice and host discrimination behavior is lacking. In this study, we studied the mate choice and host discrimination behavior of T. chilonis in experimental arenas through video tracking. Males’ mate recognition capacity was realized by perceiving the sex pheromone of females. When offered two females of different species, male could distinguish the conspecific female from Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae), a species that has overlapping hosts with T. chilonis. When placed with two females of different mating status, male preferred mating with the virgin female to the mated female. T. chilonis females could distinguish unparasitized host eggs from parasitized ones (parasitized by conspecific females or heterospecific females). They preferred to stay on and lay eggs in unparasitized host eggs. When T. chilonis females were only provided with parasitized host eggs (parasitized by T. chilonis and T. bactrae females), conspecific superparasitism occurred more often than heterospecific superparasitism. Furthermore, the host egg discrimination ability of T. chilonis females was mainly achieved through antennal perception.
To examine the association between BMI and folate concentrations in serum and red blood cells (RBC) in pregnant women.
A cross-sectional comparison of folate concentrations in serum and RBC sampled simultaneously from the same individual.
The Ottawa Hospital and Kingston General Hospital, Ontario, Canada.
Pregnant women recruited between 12 and 20 weeks of gestation.
A total of 869 pregnant women recruited from April 2008 to April 2009 were included in the final analysis. Serum folate was inversely associated and RBC folate positively associated with BMI, after adjusting for folic acid supplementation, age, gestational age at blood sample collection, race, maternal education, annual income, smoking and MTHFR 677C→T genotype. In stratified analyses, this differential association was significant in women with the MTHFR CC variant. In women with the CT and TT variants, the differential associations were in the same direction but not significant. Folic acid supplementation during pregnancy did not alter the differential association of BMI with serum and RBC folate concentration. This indicates that the current RBC folate cut-off approach for assessing risk of neural tube defects in obese women may be limited.
BMI is inversely associated with serum folate and positively associated with RBC folate in pregnant women, especially for those with the MTHFR CC variant.
A cross-sectional study was conducted from June 2013 to August 2015 to determine the seroprevalence and possible risk factors for human Toxoplasma gondii infection in Korean, Manchu, Mongol and Han ethnic groups in eastern and northeastern China. A total of 1842 serum samples, including Han (n = 802), Korean (n = 520), Manchu (n = 303) and Mongol (n = 217) groups, were analysed using enzyme-linked immunoassays to detect IgG and IgM T. gondii antibodies. The overall T. gondii IgG and IgM seroprevalences were 13·79% and 1·25%, respectively. Of these groups, Mongol ethnicity had the highest T. gondii seroprevalence (20·74%, 45/217), followed by Korean ethnicity (16·54%, 86/520), Manchu ethnicity (13·86%, 42/303) and Han ethnicity (11·35%, 98/802). Multiple analysis showed that the consumption of raw vegetables and fruits, the consumption of raw/undercooked meat and the source of drinking water were significantly associated with T. gondii infection in the Han group. Likewise, having a cat at home was identified as being associated with T. gondii infection in the Korean, Manchu and Mongol groups. Moreover, the consumption of raw/undercooked meat was identified as another predictor of T. gondii seropositivity in the Mongol group. The results of this survey indicate that T. gondii infection is prevalent in Korean, Manchu, Mongol and Han ethnic groups in the study region. Therefore, it is essential to implement integrated strategies with efficient management measures to prevent and control T. gondii infection in this region of China. Moreover, this is the first report of T. gondii infection in Korean, Manchu, and Mongol ethnic groups in eastern and northeastern China.
Major depressive disorder (MDD) is a common and disabling condition with well-established heritability and environmental risk factors. Gene–environment interaction studies in MDD have typically investigated candidate genes, though the disorder is known to be highly polygenic. This study aims to test for interaction between polygenic risk and stressful life events (SLEs) or childhood trauma (CT) in the aetiology of MDD.
The RADIANT UK sample consists of 1605 MDD cases and 1064 controls with SLE data, and a subset of 240 cases and 272 controls with CT data. Polygenic risk scores (PRS) were constructed using results from a mega-analysis on MDD by the Psychiatric Genomics Consortium. PRS and environmental factors were tested for association with case/control status and for interaction between them.
PRS significantly predicted depression, explaining 1.1% of variance in phenotype (p = 1.9 × 10−6). SLEs and CT were also associated with MDD status (p = 2.19 × 10−4 and p = 5.12 × 10−20, respectively). No interactions were found between PRS and SLEs. Significant PRSxCT interactions were found (p = 0.002), but showed an inverse association with MDD status, as cases who experienced more severe CT tended to have a lower PRS than other cases or controls. This relationship between PRS and CT was not observed in independent replication samples.
CT is a strong risk factor for MDD but may have greater effect in individuals with lower genetic liability for the disorder. Including environmental risk along with genetics is important in studying the aetiology of MDD and PRS provide a useful approach to investigating gene–environment interactions in complex traits.
While oral antidepressants reach efficacy after weeks, single-dose intravenous (i.v.) ketamine has rapid, yet time-limited antidepressant effects. We aimed to determine the efficacy and safety of single-dose i.v. ketamine augmentation of escitalopram in major depressive disorder (MDD).
Thirty outpatients with severe MDD (17-item Hamilton Rating Scale for Depression total score ⩾24) were randomized to 4 weeks double-blind treatment with escitalopram 10 mg/day+single-dose i.v. ketamine (0.5 mg/kg over 40 min) or escitalopram 10 mg/day + placebo (0.9% i.v. saline). Depressive symptoms were measured using the Montgomery–Asberg Depression Rating Scale (MADRS) and the Quick Inventory of Depressive Symptomatology – Self-Report (QIDS-SR). Suicidal ideation was evaluated with the QIDS-SR item 12. Adverse psychopathological effects were measured with the Brief Psychiatric Rating Scale (BPRS)-positive symptoms, Young Mania Rating Scale (YMRS) and Clinician Administered Dissociative States Scale (CADSS). Patients were assessed at baseline, 1, 2, 4, 24 and 72 h and 7, 14, 21 and 28 days. Time to response (⩾50% MADRS score reduction) was the primary outcome.
By 4 weeks, more escitalopram + ketamine-treated than escitalopram + placebo-treated patients responded (92.3% v. 57.1%, p = 0.04) and remitted (76.9% v. 14.3%, p = 0.001), with significantly shorter time to response [hazard ratio (HR) 0.04, 95% confidence interval (CI) 0.01–0.22, p < 0.001] and remission (HR 0.11, 95% CI 0.02–0.63, p = 0.01). Compared to escitalopram + placebo, escitalopram + ketamine was associated with significantly lower MADRS scores from 2 h to 2 weeks [(peak = 3 days–2 weeks; effect size (ES) = 1.08–1.18)], QIDS-SR scores from 2 h to 2 weeks (maximum ES = 1.27), and QIDS-SR suicidality from 2 to 72 h (maximum ES = 2.24). Only YMRS scores increased significantly with ketamine augmentation (1 and 2 h), without significant BPRS or CADSS elevation.
Single-dose i.v. ketamine augmentation of escitalopram was safe and effective in severe MDD, holding promise for speeding up early oral antidepressant efficacy.
Necrophoric behaviour is critical sanitation behaviour in social insects. However, little is known about the necrophoric responses of workers towards different developmental stages in a colony as well as its underlying mechanism. Here, we show that Solenopsis invicta workers display distinct necrophoric responses to corpses of workers and pupae. Corpses of workers killed by freezing (dead for <1 h) were carried to a refuse pile, but pupal corpses would take at least 1 day to elicit workers’ necrophoric response. Metarhizium anisopliae-infected pupal corpses accelerated the necrophoric behaviour of resident workers, with 47.5% of unaffected corpses and 73.8% infected corpses discarded by 1 day post-treatment). We found that fungus-infected pupal corpses had a higher concentration of fatty acids (palmitic acid, oleic acid and linoleic acid) on their surface. We experimentally confirmed that linoleic and oleic acids would elicit a necrophoric response in workers. The appearance of linoleic and oleic acids appeared to be chemical signals involved in recognition of pupal corpses, and M. anisopliae infection could promote the accumulation of fatty acids on surface of pupal corpses resulting in accelerated necrophoric responses of workers.
This research focuses on defining the design principles that integrate passive-system thinking into the built environment with the goal of mitigating building energy usage by self-regulating the heat gain/loss at level of building envelopes. In collaboration with TAKTL, a company that developed and uses advanced Ultra High Performance Concrete (UHPC) integrated with mold design and manufacturing of architectural elements, our research targets how specific manipulation of UHPC surface area in combination with self-regulating thermochromic response can improve building’s energy performance. By coupling the adaptive color response with surface geometry we can suggest new passive sustainable solutions that would mitigate the energy usage with no additional energy input; purely through designing the form and color adaptation for UHPC concrete Trombe wall components integrated within building façade systems. This paper outlines the first part - the thermal behavior in response to surface geometry. Such comprehensive knowledge not only enhances the possibilities within architectural design, but becomes an effective strategy in self-regulating the heat gain/loss at the building surface level, while reducing the need for mechanical building systems.
Hand, foot and mouth disease (HFMD) is an acute contagious condition caused by a spectrum of human enteroviruses. HFMD reinfection is common in the absence of cross-protection from other virus subtypes. This study focused on reinfection in children in Anhui province, China between 2008 and 2013 using surveillance system data. We classified 8960 cases as reinfected, corresponding to a rate of 2·02%. The reinfection rate was higher in boys than in girls [odds ratio (OR) 1·27, 95% confidence interval (CI) 1·21–1·32, P < 0·001], children aged < 3 years (OR 3·82, 95% CI 3·58–4·07, P < 0·001), and children living in rural areas (OR 1·09, 95% CI 1·04–1·14, P = 0·001). The reinfection rate in children who were originally infected with non-enterovirus A71 (non-EVA71) enteroviruses was higher than those infected with EVA71 (OR 1·36, 95% CI 1·02–1·80, P = 0·034). Influential factors of reinfection rate included annual incidence (β coefficient = 0·715, P = 0·002) and the proportion of EVA71 in patients with mild HFMD (β coefficient = −0·509, P = 0·018). These results demonstrate that boys aged <3 years, especially those in rural areas or regions with a lower EVA71 proportion are more prone to reinfection, and specific health education programmes should be developed to protect these susceptible populations.