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Few studies have used genomic epidemiology to understand tuberculosis (TB) transmission in rural and remote settings – regions often unique in history, geography and demographics. To improve our understanding of TB transmission dynamics in Yukon Territory (YT), a circumpolar Canadian territory, we conducted a retrospective analysis in which we combined epidemiological data collected through routine contact investigations with clinical and laboratory results. Mycobacterium tuberculosis isolates from all culture-confirmed TB cases in YT (2005–2014) were genotyped using 24-locus Mycobacterial Interspersed Repetitive Units-Variable Number of Tandem Repeats (MIRU-VNTR) and compared to each other and to those from the neighbouring province of British Columbia (BC). Whole genome sequencing (WGS) of genotypically clustered isolates revealed three sustained transmission networks within YT, two of which also involved BC isolates. While each network had distinct characteristics, all had at least one individual acting as the probable source of three or more culture-positive cases. Overall, WGS revealed that TB transmission dynamics in YT are distinct from patterns of spread in other, more remote Northern Canadian regions, and that the combination of WGS and epidemiological data can provide actionable information to local public health teams.
Nano-structured thin films have a variety of applications from waveguides, gaseous sensors to piezoelectric devices. Grazing Incidence Small Angle x-ray Scattering images enable classification of such materials. One challenge is to determine structure information from scattering patterns alone. This paper highlights the design of multiple Convolutional Neural Networks (CNN) to classify nanoparticle orientation in a thin film by learning scattering patterns. The network was trained on several thin films with a success rate of 94%. We demonstrate CNN robustness under different noises as well as demonstrate the potential of our proposed approach as a strategy to decrease scattering pattern analysis time.
A multi-scale strategy is employed in the paper to investigate the thermo-mechanical properties of 2.5D angle-interlock woven shape memory polymer composites (SMPCs). In the study, the mesoscopic model of 2.5D woven SMPCs and microscopic model of yarns are firstly developed. After that, the themo-viscoelastic constitutive relationship of the yarn is described in the form of hereditary integral and the parameters of relaxation moduli are obtained from nonlinear fitting of Prony series based on the results of finite element method (FEM). Based on the multi-scale models and the constitutive relationship, the effects of warp and weft arranged densities on viscoelastic properties of 2.5D woven SMPCs are studied in detail. Finally, the shape memory behavior along the warp direction in small strain region is also analyzed. The research in the paper lays a foundation for design and application of woven SMPCs in engineering.
In several lately published studies, the association between single-nucleotide polymorphism (SNP, rs12252) of IFITM3 and the risk of influenza is inconsistent. To further understand the association between the SNP of IFITM3 and the risk of influenza, we searched related studies in five databases including PubMed published earlier than 9 November 2017. Ten sets of data from nine studies were included and data were analysed by Revman 5.0 and Stata 12.0 in our updated meta-analysis, which represented 1365 patients and 5425 no-influenza controls from four different ethnicities. Here strong association between rs12252 and influenza was found in all four genetic models. The significant differences in the allelic model (C vs. T: odds ratio (OR) = 1.35, 95% confidence interval (CI) (1.03–1.79), P = 0.03) and homozygote model (CC vs. TT: OR = 10.63, 95% CI (3.39–33.33), P < 0.00001) in the Caucasian subgroup were discovered, which is very novel and striking. Also novel discoveries were found in the allelic model (C vs. T: OR = 1.37, 95% CI (1.08–1.73), P = 0.009), dominant model (CC + CT vs. TT: OR = 1.48, 95% CI (1.08–2.02), P = 0.01) and homozygote model (CC vs. TT: OR = 2.84, 95% CI (1.36–5.92), P = 0.005) when we compared patients with mild influenza with healthy individuals. Our meta-analysis suggests that single-nucleotide T to C polymorphism of IFITM3 associated with increasingly risk of severe and mild influenza in both Asian and Caucasian populations.
Sufficient amino acid (AA) transport is essential to ensure the normal physiological function and growth of growing animals. The processes of AA sensing and transport in humans and murine animals, but rarely in goats, have been arousing great interest recently. This study was conducted to investigate the messenger RNA expression patterns of lysophosphatidic acid receptor 5 (LPAR5), guanine nucleotide-binding protein α-transducing 3 (GNAT3) and important partial AA transporters in digestive tracts, metabolic organs and muscles of growing goats. The results showed that these genes were widely expressed in goats, and had different expression patterns. LPAR5, GNAT3, solute carrier (SLC38A2), SLC7A7, SLC7A1 and SLC3A1 were rarely expressed in the rumen, but were highly expressed in the abomasum and intestine which are the main sites of AA absorption. GNAT3, SLC38A1, SLC38A2, SLC6A19, SLC7A7 and SLC7A1 showed comparatively high expression in the pancreas and the vital digestive glands, and the relatively high expression of these nine genes were noted in the tibialis posterior, the active muscle in energy metabolism. The correlation analysis showed that there were certain positive correlation among most genes. The current results indicate that the AA sensing and transport occur extensively in the abomasum and small intestine, metabolic organs and muscle tissues of ruminants, and that related genes have tissue specificity.
Hydrogen is an important intermediate that is produced during carbohydrate fermentation to volatile fatty acid and utilized by methanogens to produce methane in the rumen. Ruminal volatile fatty acid and dissolved methane concentrations are more than 500 times greater than dissolved hydrogen concentration. Therefore, we hypothesized that dissolved hydrogen might have a higher sensitivity in response to dietary changes compared with volatile fatty acid and dissolved methane. Using goats, we investigated the effects of increasing dietary starch content (maize replaced with wheat bran) and supplementing with rhubarb rhizomes and roots on the relationships among dissolved hydrogen, dissolved methane and other fermentation end products. The study was conducted in a replicated 4×4 Latin square with a 2×2 factorial arrangement of four treatments: two starch levels (220 v. 320 g/kg dry matter (DM)), without and with rhubarb supplement (0% v. 2.8% of total mixed ration). Increased dietary starch and rhubarb supplementation did not alter volatile fatty acid concentrations or methane emissions in terms of g/day, g/g DM intake and g/g organic matter digested. However, goats fed the high-starch diet had greater dissolved hydrogen (P=0.005) and relative abundance of Selenomonas ruminantium (P<0.01), and lower (P=0.02) copy number of protozoa than those fed the low-starch diet. Rhubarb increased ruminal dissolved H2 (P=0.03) and total volatile fatty acid concentration (P<0.001), but decreased copies of bacteria (P=0.002). In conclusion, dissolved hydrogen appears to be more sensitive to dietary changes with starch content and rhubarb supplementation, when compared with volatile fatty acid concentrations and methane production.
The gastrointestinal tract (GIT) of animals is capable of sensing various kinds of nutrients via G-protein coupled receptor-mediated signaling transduction pathways, and the process is known as ‘gut nutrient chemosensing’. GPR40, GPR41, GPR43 and GPR119 are chemoreceptors for free fatty acids (FFAs) and lipid derivatives, but they are not well studied in small ruminants. The objective of this study is to determine the expression of GPR40, GPR41, GPR43 and GPR119 along the GIT of kid goats under supplemental feeding (S) v. grazing (G) during early development. In total, 44 kid goats (initial weight 1.35±0.12 kg) were slaughtered for sampling (rumen, abomasum, duodenum, jejunum, ileum, cecum, colon and rectum) between days 0 and 70. The expression of GPR41 and GPR43 were measured at both mRNA and protein levels, whereas GPR40 and GPR119 were assayed at protein level only. The effects of age and feeding system on their expression were variable depending upon GIT segments, chemoreceptors and expression level (mRNA or protein), and sometimes feeding system × age interactions (P<0.05) were observed. Supplemental feeding enhanced expression of GPR40, GPR41 and GPR43 in most segments of the GIT of goats, whereas G enhanced expression of GPR119. GPR41 and GPR43 were mainly expressed in rumen, abomasum and cecum, with different responses to age and feeding system. GPR41 and GPR43 expression in abomasum at mRNA level was greatly (P<0.01) affected by both age and feeding system; whereas their expression in rumen and abomasum at protein level were different, feeding system greatly (P<0.05) affected GPR41 expression, but had no effect (P>0.05) on GPR43 expression; and there were no feeding system×age interactions (P>0.05) on GPR41 and GPR43 protein expression. The expression of GPR41 and GPR43 in rumen and abomasum linearly (P<0.01) increased with increasing age (from days 0 to 70). Meanwhile, age was the main factor affecting GPR40 expression throughout the GIT. These outcomes indicate that age and feeding system are the two factors affecting chemoreceptors for FFAs and lipid derivatives expression in the GIT of kids goats, and S enhanced the expression of chemoreceptors for FFAs, whereas G gave rise to greater expression of chemoreceptors for lipid derivatives. Our results suggest that enhanced expression of chemoreceptors for FFAs might be one of the benefits of early supplemental feeding offered to young ruminants during early development.
Offering large portions of high-energy-dense (HED) foods increases overall intake in children and adults. This is known as the portion size effect (PSE). It is robust, reliable and enduring. Over time, the PSE may facilitate overeating and ultimately positive energy balance. Therefore, it is important to understand what drives the PSE and what might be done to counter the effects of an environment promoting large portions, especially in children. Explanations for the PSE are many and diverse, ranging from consumer error in estimating portion size to simple heuristics such as cleaning the plate or eating in accordance with consumption norms. However, individual characteristics and hedonic processes influence the PSE, suggesting a more complex explanation than error or heuristics. Here PSE studies are reviewed to identify interventions that can be used to downsize portions of HED foods, with a focus on children who are still learning about social norms for portion size. Although the scientific evidence for the PSE is robust, there is still a need for creative downsizing solutions to facilitate portion control as children and adolescents establish their eating habits.
Coinfection with human immunodeficiency virus (HIV) and viral hepatitis is associated with high morbidity and mortality in the absence of clinical management, making identification of these cases crucial. We examined characteristics of HIV and viral hepatitis coinfections by using surveillance data from 15 US states and two cities. Each jurisdiction used an automated deterministic matching method to link surveillance data for persons with reported acute and chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections, to persons reported with HIV infection. Of the 504 398 persons living with diagnosed HIV infection at the end of 2014, 2.0% were coinfected with HBV and 6.7% were coinfected with HCV. Of the 269 884 persons ever reported with HBV, 5.2% were reported with HIV. Of the 1 093 050 persons ever reported with HCV, 4.3% were reported with HIV. A greater proportion of persons coinfected with HIV and HBV were males and blacks/African Americans, compared with those with HIV monoinfection. Persons who inject drugs represented a greater proportion of those coinfected with HIV and HCV, compared with those with HIV monoinfection. Matching HIV and viral hepatitis surveillance data highlights epidemiological characteristics of persons coinfected and can be used to routinely monitor health status and guide state and national public health interventions.
In this paper, a new type of fixed-wing vertical take-off and landing, unmanned aerial vehicle (UAV) has been designed. Thrust-vector direct force control has been introduced in three axes to make UAV exhibit superior manoeuverability in transition flight. Considering the characteristics of UAV's dynamic model, which are non-linear, non-affine, and have redundant input, a two-stage progressive optimal control allocation method is developed, which can optimise position and attitude control in synthetical, and motivate effectors to generates desired force and moments. A task-oriented weight selection scheme is proposed to make objective function suitable for different tasks and flight conditions. In addition, a general constraint strategy is designed to guarantee the feasibility of optimal allocation results, which can largely reduce the onboard computation time. Simulations show that UAV can adjust flight attitude and use control effectors in an optimal way, and demonstrating satisfactory tracking of low-speed high-manoeuver flight paths.
Based on unstructured hybrid grid and dynamic overlapping grid technique, numerical simulations of Unsteady Reynolds Averaged Navier-Stokes equations were performed and investigation on isolated propeller aerodynamic characteristics and effects of propeller slipstream on turboprops were undertaken. The computational grid consisted of rotational subzone of propeller and stationary major-zone of aircraft, and walls criterion was used in the automatic hole-cutting procedure. Distance weight interpolation and tri-linear interpolation were developed to transfer information between the rotational and stationary subzones. The boundaries of overlapping grids were optimized for fixed axis rotation. The governing equations were solved by dual-time method and Lower Upper-Symmetric Gauss-Seidel method. The method and grid technique were verified by isolated propeller configuration and the computational results were in well agreement with the experimental data. The grid independence was studied to establish the numerical results. Finally, the flow around a turboprop case was simulated and the influence of propeller slipstream was presented by analyzing the surface pressure contours, profile pressure distribution, vorticity contours and profile streamline. It's indicated that the slipstream accelerates and rotates the free stream flow, changing the local angle of attack, enhancing the downwash effects, affecting the pressure distribution on wing and horizontal tail, as well as increasing the drag coefficient, pitching moment coefficient and the slope of lift coefficient.
Placental transport of vitamin D and other nutrients (e.g. amino acids, fats and glucose) to the fetus is sensitive to maternal and fetal nutritional cues. We studied the effect of maternal calorific restriction on fetal vitamin D status and the placental expression of genes for nutrient transport [aromatic T-type amino acid transporter-1 (TAT-1); triglyceride hydrolase/lipoprotein uptake facilitator lipoprotein lipase (LPL)] and vitamin D homeostasis [CYP27B1; vitamin D receptor (VDR)], and their association with markers of fetal cardiovascular function and skeletal muscle growth. Pregnant sheep received 100% total metabolizable energy (ME) requirements (control), 40% total ME requirements peri-implantation [PI40, 1–31 days of gestation (dGA)] or 50% total ME requirements in late gestation (L, 104–127 dGA). Fetal, but not maternal, plasma 25-hydroxy-vitamin D (25OHD) concentration was lower in PI40 and L maternal undernutrition groups (P<0.01) compared with the control group at 0.86 gestation. PI40 group placental CYP27B1 messenger RNA (mRNA) levels were increased (P<0.05) compared with the control group. Across all groups, higher fetal plasma 25OHD concentration was associated with higher skeletal muscle myofibre and capillary density (P<0.05). In the placenta, higher VDR mRNA levels were associated with higher TAT-1 (P<0.05) and LPL (P<0.01) mRNA levels. In the PI40 maternal undernutrition group only, reduced fetal plasma 25OHD concentration may be mediated in part by altered placental CYP27B1. The association between placental mRNA levels of VDR and nutrient transport genes suggests a way in which the placenta may integrate nutritional cues in the face of maternal dietary challenges and alter fetal physiology.
An outbreak of gastroenteritis affected 453 attendees (attack rate 28·5%) of six separate events held at a hotel in Singapore. Active case detection, case-control studies, hygiene inspections and microbial analysis of food, environmental and stool samples were conducted to determine the aetiology of the outbreak and the modes of transmission. The only commonality was the food, crockery and cutlery provided and/or handled by the hotel's Chinese banquet kitchen. Stool specimens from 34 cases and 15 food handlers were positive for norovirus genogroup II. The putative index case was one of eight norovirus-positive food handlers who had worked while they were symptomatic. Several food samples and remnants tested positive for Escherichia coli or high faecal coliforms, aerobic plate counts and/or total coliforms, indicating poor food hygiene. This large common-source outbreak of norovirus gastroenteritis was caused by the consumption of contaminated food and/or contact with contaminated crockery or cutlery provided or handled by the hotel's Chinese banquet kitchen.
Ectropis grisescens Warren and Ectropis obliqua (Prout) are two morphologically similar sibling species with overlapping ranges. In this study, manipulative laboratory experiments were conducted to examine the possibility of reproductive interference in sympatric populations of E. grisescens and E. obliqua and the potential consequences of the mating interaction. Our results showed that the presence of males or females of different species could incur mating interference and significant reduction of F1 offspring. The reduction was not significant relevant to the initial relative abundance of E. grisescens and E. obliqua. Detailed observations of mating opportunity showed that female mating frequencies of both species were not significantly affected by the absolute species density, but the mating success of E. obliqua females with conspecific males depended on species ratio. In addition, adding males to the other species resulted in lower number of offspring suggesting that the males’ behaviour might be linked with mating interference. Males of both E. grisescens and E. obliqua could interfere the intraspecific mating of the other species, but the impact of the mating interference differed. These combined data indicated that asymmetric reproductive interference existed in E. grisescens and E. obliqua under laboratory conditions, and the offspring of the mixed species were significantly reduced. The long term outcome of this effect is yet to be determined since additional reproductive factors such as oviposition rate and progeny survival to adulthood may reduce the probability of demographic displacement of one species by the other in overlapping niches.
Many jurisdictions in the USA and globally are considering raising the prices of sugar-sweetened beverages (SSB) through taxes as a strategy to reduce their consumption. The objective of the present study was to identify whether the rationale provided for an SSB price increase affects young adults’ behavioural intentions and attitudes towards SSB.
Participants were randomly assigned to receive one of eight SSB price increase rationales. Intentions to purchase SSB and attitudes about the product and policy were measured.
A forty-six-item cross-sectional Internet survey.
Undergraduate students (n 494) at a large US Midwestern university.
Rationale type was significantly associated with differences in participants’ purchasing intentions for the full sample (F7,485=2·53, P=0·014). Presenting the rationale for an SSB price increase as a user fee, an effort to reduce obesity, a strategy to offset health-care costs or to protect children led to lower SSB purchasing intentions compared with a message with no rationale. Rationale type was also significantly associated with differences in perceptions of soda companies (F7,485=2·10, P=0·043); among low consumers of SSB, messages describing the price increase as a user fee or tax led to more negative perceptions of soda companies.
The rationale attached to an SSB price increase could influence consumers. However, these message effects may depend on individuals’ level of SSB consumption.
It remains unclear whether the topological deficits of the white matter network documented in cross-sectional studies of chronic schizophrenia patients are due to chronic illness or to other factors such as antipsychotic treatment effects. To answer this question, we evaluated the white matter network in medication-naive first-episode schizophrenia patients (FESP) before and after a course of treatment.
We performed a longitudinal diffusion tensor imaging study in 42 drug-naive FESP at baseline and then after 8 weeks of risperidone monotherapy, and compared them with 38 healthy volunteers. Graph theory was utilized to calculate the topological characteristics of brain anatomical network. Patients’ clinical state was evaluated using the Positive and Negative Syndrome Scale (PANSS) before and after treatment.
Pretreatment, patients had relatively intact overall topological organizations, and deficient nodal topological properties primarily in prefrontal gyrus and limbic system components such as the bilateral anterior and posterior cingulate. Treatment with risperidone normalized topological parameters in the limbic system, and the enhancement positively correlated with the reduction in PANSS-positive symptoms. Prefrontal topological impairments persisted following treatment and negative symptoms did not improve.
During the early phase of antipsychotic medication treatment there are region-specific alterations in white matter topological measures. Limbic white matter topological dysfunction improves with positive symptom reduction. Prefrontal deficits and negative symptoms are unresponsive to medication intervention, and prefrontal deficits are potential trait biomarkers and targets for negative symptom treatment development.