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The nutritional intake of Tibetan sheep on the harsh Qinghai-Tibetan Plateau (QTP) is often under maintenance requirements, especially during the long, cold winter. However, they have adapted well and even thrive under these conditions. The aim of this study was to gain insight into how the rumen epithelium of Tibetan sheep has adapted to the consumption of low energy level diets. For this purpose, we compared Tibetan and Small-tailed Han sheep (n = 24 of each breed, all wethers and 1.5 years of age), which were divided randomly into one of four groups and offered ad libitum diets of different digestible energy (DE) densities: 8.21, 9.33, 10.45 and 11.57 MJ DE/kg dry matter (DM). The Tibetan sheep had higher rumen concentrations of total SCFAs, acetate, butyrate and iso-acids but lower concentrations of propionate than Small-tailed Han sheep. The Tibetan sheep had higher absorption capability of SCFAs due to the greater absorption surface area and higher mRNA expression of the SCFAs absorption relative genes than Small-tailed Han sheep. For the metabolism of SCFAs in the rumen epithelium, the Small-tailed Han sheep showed higher utilization of the ketogenesis pathway than Tibetan sheep, however, Tibetan sheep had greater regulation capacity in SCFAs metabolism pathways. These differences between breeds allowed the Tibetan sheep to have greater capability of absorbing SCFAs and better capacity to regulate the metabolism of SCFAs, which would allow them to cope with low energy intake better than Small-tailed Han sheep.
A digraph is called oriented if there is at most one arc between two distinct vertices. An oriented graph
is nonsingular if its adjacency matrix
is nonsingular. We characterise all nonsingular oriented graphs from three classes: graphs in which cycles are vertex disjoint, graphs in which all cycles share exactly one common vertex and graphs formed by cycles sharing a common path. As a straightforward corollary, the singularity of oriented bicyclic graphs is determined.
Malnutrition and acute kidney injury (AKI) are common complications in hospitalized patients, and both increase mortality; however, the relationship between them is unknown. This is a retrospective propensity score matching study enrolling 46,549 inpatients, aimed to investigate the association between Nutritional Risk Screening 2002 (NRS-2002) and AKI, and to assess the ability of NRS-2002 and AKI in predicting prognosis. In total, 37,190 (80%) and 9,359 (20%) patients had NRS-2002 scores < 3 and ≥ 3, respectively. Patients with NRS-2002 scores ≥ 3 had longer lengths of stay (12.6±7.8 days vs. 10.4±6.2 days, P < 0.05), higher mortality rates (9.6% vs. 2.5%, P<0.05), and higher incidence of AKI (28% vs. 16%, P < 0.05) than normal nutritional patients. The NRS-2002 showed a strong association with AKI, that is, the risk of AKI changed in parallel with the score of the NRS-2002. In short- and long-term survival, patients with a lower NRS-2002 score or who did not have AKI achieved a significantly lower risk of mortality than those with a high NRS-2002 score or AKI. Univariate Cox regression analyses indicated that both the NRS-2002 and AKI were strongly related to long-term survival (area under the curve (AUC) 0.79 and 0.71) and that the combination of the two showed better accuracy (AUC 0.80) than the individual variables. In conclusion, malnutrition can increase the risk of AKI, and both AKI and malnutrition can worsen the prognosis, that the undernourished patients who develop AKI yield far worse prognosis than normal nutritional patients.
A piezoelectric biomedical microelectromechanical system (bioMEMS) cantilever device was designed and fabricated to act as either a sensing element for muscle tissue contraction or as an actuator to apply mechanical force to cells. The sensing ability of the piezoelectric cantilevers was shown by monitoring the electrical signal generated from the piezoelectric aluminum nitride in response to the contraction of iPSC-derived cardiomyocytes cultured on the piezoelectric cantilevers. Actuation was demonstrated by applying electrical pulses to the piezoelectric cantilever and observing bending via an optical detection method. This piezoelectric cantilever device was designed to be incorporated into body-on-a-chip systems.
Anatase phase NOx/S6+–TiO2 (x= 0, 1) film with high solar-driven activity has been successfully prepared via electro-assisted oxidation processes. The morphological and structural properties of the film were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction, while the optical property was detected by UV-vis-NIR absorption spectroscopy. The results showed that the NOx/S6+–TiO2 film was composed of “flower-like” microvoids structure and displayed broad and strong optical absorption at around 544 and 1500 nm. Transient photocurrent response, photoluminescence spectroscopy, and electrochemical impedance spectroscopy indicated that the generation and separation of photogenerated charges were significantly enhanced under simulated solar irradiation. The NOx/S6+–TiO2 film exhibited excellent photoelectrocatalytic activity for the degradation of methyl orange (MO), and the decoloration rate and TOC removal respectively reached 98.97 and 59.44% at 20 min under solar irradiation. The film still had good stability after reusing ten times. Furthermore, a possible mechanism of photoelectrocatalysis was suggested in MO degradation by using NOx/S6+–TiO2 film.
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.
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
There is a dearth of data on the iodine balance studies of Chinese population. In the present study, we aimed to explore the appropriate recommended nutrient intake (RNI) of iodine based on healthy Chinese women. A 4-week study was conducted in twenty-five Chinese euthyroid women. Uniform diets with different iodine contents were provided in two different periods, in which non-iodised salt was given in the first 3 weeks, followed by 1 week of iodised salt administration. The total iodine intake from diet, water and air as well as the total iodine excretion through urine, faeces and respiration were monitored and determined. The sweat iodine loss was also considered. Moreover, the regression curve model was established between the 24 h iodine intake and 24 h iodine excretion. The 24 h iodine intake in the two periods was 194·8 (sd 62·9) and 487·1 (sd 177·3) μg/d, respectively. The 24 h iodine excretion was 130·9 (sd 39·5) and 265·4 (sd 71·8) μg/d, respectively. Both 24 h iodine intake and 24 h iodine excretion of the two periods were significantly different (all P<0·05). The iodised salt contributed approximately 62·7 % of the total daily iodine intake. Moreover, 92·3 % (277/300) of samples were in positive balance, while twenty-three cases were in negative balance. Our data show that the estimated average requirement for iodine was 110·5 μg/d. Therefore, the RNI for iodine to non-pregnant, non-lactating Chinese women was 154·7 μg/d.
Sex-specific diagnostic cut-offs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction (MI). The objective of this study was to quantify test characteristics of sex-specific cut-offs of a single, high-sensitivity cardiac troponin T (hs-cTnT) assay for 7-day MI in patients with chest pain.
This observational cohort study included consecutive emergency department (ED) patients with suspected cardiac chest pain from four Canadian EDs who had an hs-cTnT assay performed within 60 minutes of ED arrival. The primary outcome was MI at 7 days. We quantified test characteristics (sensitivity, negative predictive value [NPV], likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific, rule-out cut-offs. We calculated the net reclassification index compared to universal rule-out cut-offs.
In 7,130 patients (3,931 men and 3,199 women), the 7-day MI incidence was 7.38% among men and 3.78% among women. Optimal sex-specific cut-offs (<8 ng/L for men and <7 ng/L for women) had a 98.5% sensitivity for MI and ruled out MI in 55.8% of patients. This would enable an absolute increase in the proportion of patients who were able to be ruled out with a single hs-cTnT of 13.2% to 22.2%, depending on the universal rule-out concentration used as a comparator.
Sex-specific hs-cTnT cut-offs for ruling out MI at ED arrival may improve classification performance, enabling more patients to be safely ruled out at ED arrival. However, differences between sex-specific and universal cut-off concentrations are within the variation of the assay, limiting the clinical utility of this approach. These findings should be confirmed in other data sets.
Ti–Al alloys are established as promising candidates for aerospace applications due to their lightweight, good elevated temperature strength, and decent corrosion resistance. In this study, a Ti–51Al (at.%) alloy is fabricated by spray deposition. The effects of temperature and strain rate on the deformation behavior of the spray-deposited Ti–Al alloy are investigated. The microstructural evolution of the Ti–Al alloy with different deformation temperatures is discussed in detail. A strain-dependent constitutive equation was proposed to predict the flow stresses at the elevated temperatures for the spray-deposited Ti–Al alloy. The microstructure of the as-deposited Ti–51Al alloy exhibits a α2/γ lamellar-structure with average size 25 ± 2 μm, due to the high cooling rate observed during solidification. The lamellar structure is embedded on a γ matrix. The amount of the α2/γ lamellar-structure reduces gradually with increasing the hot deformation temperature. After hot isostatic pressing at 1523 K, the microstructure is mainly comprised of the γ matrix.
With the development of remote sensing and geostatistical technology, complex environmental variables are increasingly easily quantified and applied in modelling soil organic carbon (SOC). However, this emphasizes data redundancy and multicollinearity problems adding to the difficulty in selecting dominant influential auxiliary variables and uncertainty in estimating SOC stocks. The current paper considers the spatial characteristics of SOC density (SOCD) to construct prediction models of SOCD on the basis of reducing the data dimensionality and complexity using the principal component analysis (PCA) method. A total of 260 topsoil samples were collected from Chahe town, China. Eight environmental variables (elevation, aspect, slope, normalized difference vegetation index, normalized difference moisture index, nearest distance to construction area and road, and land use degree comprehensive index) were pre-analysed by PCA and then extracted as the main principal component variables to construct prediction models. Two geostatistical approaches (ordinary kriging and ordinary co-kriging) and two regression approaches (ordinary least squares and geographically weighted regression (GWR)) were used to estimate SOCD. Results showed that PCA played an important role in reducing the redundancy and multicollinearity of the auxiliary variables and GWR achieved the highest prediction accuracy in these four models. GWR considered not only the spatial characteristics of SOCD but also the related valuable information of the auxiliary attributes. In summary, PCA-GWR is a promising spatial method used here to predict SOC stocks.
Evidence on the association between maternal Hb concentration and preterm birth (PTB) risk is inconclusive. This paper aimed to explore whether women with anaemia or high Hb level before pregnancy would be at higher risk of PTB. We conducted a population-based cohort study with 2 722 274 women aged 20–49 years, who participated in National Free Pre-Pregnancy Checkups Project between 2013 and 2015 and delivered a singleton before 2016 in rural China. Logistic models were used to estimate OR and 95 % CI after adjusting for confounding variables. Restricted cubic spline models were applied to evaluate the dose–response relationships. A total of 192 819 (7·08 %) women had preterm deliveries. Compared with women with Hb of 110–149 g/l, the multivariable-adjusted OR for PTB was 1·19 (95 % CI 0·98, 1·44) for women with Hb<70 g/l, 1·01 (95 % CI 0·97, 1·03) for 70–99 g/l, 0·96 (95 % CI 0·95, 0·98) for 100–109 g/l, 1·04 (95 % CI 1·01, 1·06) for 150–159 g/l, 1·11 (95 % CI 1·05, 1·17) for 160–169 g/l and 1·19 (95 % CI 1·11, 1·27) for ≥170 g/l, respectively. The multivariable-adjusted OR for very PTB (VPTB) was 1·07 (95 % CI 1·03, 1·12) and 1·06 (95 % CI 1·01, 1·12) for women with Hb <110 and ≥150 g/l, compared with those with Hb of 110–149 g/l, respectively. Our study identified a U-shaped relationship between maternal preconception Hb concentration and PTB risk. Both preconception anaemia and high Hb level can significantly increase VPTB risk. Appropriate intervention for women with abnormal Hb levels before pregnancy is very necessary.
Using time-resolved laser-scanning confocal microscopy and ultrafast optical pump/THz probe spectroscopy, we measure photoluminescence (PL) and THz-conductivity in perovskite micro-crystals and films. PL quenching and lifetime variations occur from local heterogeneity. Ultrafast THz-spectra measure sharp quantum transitions from excitonic Rydberg states, providing weakly bound excitons with a binding energy of ~13.5 meV at low temperatures. Ab-initio electronic structure calculations give a direct band gap of 1.64 eV, a dielectric constant of ~18, heavy electrons, and light holes, resulting in weakly bound excitons, consistent with the binding energies from the experiment. The complementary spectroscopy and simulations reveal fundamental insights into perovskite light-matter interactions.
Ethanolamine (Etn) contained in milk is the base constituent of phosphatidylethanolamine and is required for the proliferation of intestinal epithelial cells and bacteria, which is important for maintenance of the gut microbiome and intestinal development. The present study investigated the effect of Etn on intestinal function and microbiome using 21-d-old Sprague–Dawley rats treated with 0, 250, 500 and 1000 μm Etn in drinking water for 2 weeks immediately after weaning. Growth performance, intestinal morphology, antioxidant capacity and mucosal immunity, as well as gut microbiota community composition, were evaluated. Metagenomic prediction and metabolic phenotype analysis based on 16S RNA sequencing were also carried out to assess changes in metabolic functions. We found that weaned rats administered 500 μm Etn enhanced mucosal antioxidant capacity, as evidenced by higher superoxide dismutase and glutathione peroxidase levels in the jejunum (P<0·05) compared with those in the control group. Predominant microbes including Bacteroidetes, Proteobacteria, Elusimicrobia and Tenericutes were altered by different levels of Etn compared with the control group. An Etn concentration of 500 µm shifted colonic microbial metabolic functions that are in favour of lipid- and sugar-related metabolism and biosynthesis. Etn also altered the metabolic phenotypes such as anaerobic microbial counts, and oxidative stress tolerance at over 250 µm. This is the first report for a role of Etn in modifying gut microbiota and intestinal functions. Our findings highlighted the important role of Etn in shaping gut microbial community and promotes intestinal functions, which may provide a better insight of breast-feeding to infant’s gut health.
Introduction: ex-specific diagnostic cutoffs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction. Sex-specific cutoffs for ruling in MI improve the sensitivity of the assay for MI among women, and improve the specificity of diagnosis among men. We hypothesized that the use of sex-specific high-sensitivity Troponin T (hsTnT) cutoffs for ruling out MI at the time of ED arrival would improve the classification efficiency of the assay by enabling more patients to have MI ruled out at the time of ED arrival while maintaining diagnostic sensitivity. The objective of this study was to quantify the test characteristics of sex-specific cutoffs of an hsTnT assay for acute myocardial infarction (AMI) when performed at ED arrival in patients with chest pain. Methods: This retrospective study included consecutive ED patients with suspected cardiac chest pain evaluated in four urban EDs were, excluding those with ST-elevation AMI, cardiac arrest or abnormal kidney function. The primary outcomes was AMI at 7 days. Secondary outcomes included major adverse cardiac events (MACE: all-cause mortality, AMI and revascularization) and the individual MACE components. We quantified test characteristics (sensitivity, negative predictive value, likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific rule-out cutoffs. We calculated net reclassification improvement compared to universal rule-out cutoffs of 5ng/L (the assays limit of detection) and 6ng/L (the FDA-approved limit of quantitation for US laboratories). Results: 7130 patients, including 3931 men and 3199 women, were included. The 7-day incidence of AMI was 7.38% among men and 3.78% among women. Universal cutoffs of 5 and 6 ng/L ruled out AMI with 99.7% sensitivity in 33.6 and 42.2% of patients. The best-performing combination of sex-specific cutoffs (8g/L for men and 6ng/L for men) ruled out AMI with 98.7% sensitivity in 51.9% of patients. Conclusion: Sex-specific hsTnT cutoffs for ruling out AMI at ED arrival may achieve substantial improvement in classification performance, enabling more patients to be ruled out at ED arrival, while maintaining acceptable diagnostic sensitivity for AMI. Universal and sex-specific rule-out cutoffs differ by only small changes in hsTnT concentration. Therefore, these findings should be confirmed in other datasets.
Introduction: Patients with chronic kidney disease (CKD) are at high risk of cardiovascular events, and have worse outcomes following acute myocardial infarction (AMI). Cardiac troponin is often elevated in CKD, making the diagnosis of AMI challenging in this population. We sought to quantify test characteristics for AMI of a high-sensitivity troponin T (hsTnT) assay performed at emergency department (ED) arrival in CKD patients with chest pain, and to derive rule-out cutoffs specific to patient subgroups stratified by estimated glomerular filtration rate (eGFR). We also quantified the sensitivity and classification performance of the assays limit of detection (5 ng/L) and the FDA-approved limit of quantitation (6 ng/L) for ruling out AMI at ED arrival. Methods: Consecutive patients in four urban EDs from the 2013 calendar year with suspected cardiac chest pain who had a Roche Elecsys hsTnT assay performed on arrival were included f. This analysis was restricted to patients with an eGFR< 60 ml/min/1.73m2. The primary outcome was 7-day AMI. Secondary outcomes included major adverse cardiac events (death, AMI and revascularization). Test characteristics were calculated and ROC curves were generated for eGFR subgroups. Results: 1416 patients were included. 7-day AMI incidence was 10.1%. 73% of patients had an initial hsTnT concentration greater than the assays 99th percentile (14 ng/L). TCurrently accepted cutoffs to rule out MI at ED arrival ( 5 ng/L and 6 ng/L) had 100% sensitivity for AMI, but no patients with an eGFR less than 30 ml/min/1.73M had hsTnT concentrations below these thresholds. We derived eGFR-adjusted cutoffs to rule out MI with sensitivity >98% at ED arrival, which were able to rule out 6-42% of patients, depending on eGFR category. The proportion of patients able to be accurately ruled-in with a single hsTnT assay was substantially lower among patients with an eGFR <30 ml/min/1.73m2 (6-20% vs 25-43%). We also derived eGFR-adjusted cutoffs to rule-in AMI with specificity >90%, which accurately ruled-in up to 18% of patients. Conclusion: Cutoffs achieving acceptable diagnostic performance for AMI using single hsTnT sampling on ED arrival may have limited clinical utility, particularly among patients with very low eGFR. The ideal diagnostic strategy for AMI in patients with CKD likely involves serial high-sensitivity troponin testing with diagnostic thresholds customized to different eGFR categories.
To observe the five-year efficacy of standardised specific subcutaneous immunotherapy for house dust mite allergy in monosensitised and polysensitised children with persistent allergic rhinitis.
From January 2007 to August 2009, 236 children with persistent allergic rhinitis were divided into 2 groups: 1 group received standardised specific subcutaneous immunotherapy using house dust mite extract; the other received pharmacotherapy with intranasal corticosteroids and oral antihistamines. A total of 193 patients (106 in the immunotherapy group and 87 in the pharmacotherapy group) completed treatment. Scores for symptoms, total medication and quality of life were evaluated.
The subcutaneous immunotherapy group demonstrated a significant reduction in visual analogue scale scores, Rhinoconjunctivitis Quality of Life Questionnaire scores and total medication scores (p < 0.05) compared with the pharmacotherapy group. No significant differences in the visual analogue scale and Rhinoconjunctivitis Quality of Life Questionnaire scores were found between the polysensitised and monosensitised subgroups (p > 0.05). No serious adverse events occurred.
Standardised subcutaneous immunotherapy has long-term efficacy for children with persistent allergic rhinitis. Single-allergen subcutaneous immunotherapy was appropriate for allergic rhinitis caused by multiple allergens, including house dust mites, in the paediatric population.
be a ring and
. In this paper, we give some characterizations of the
-inverse in terms of the direct sum decomposition, the annihilator, and the invertible elements. Moreover, elements with equal
-idempotents related to their
-inverses are characterized, and the reverse order rule for the
-inverse is considered.
With lower turbulence and less rigorous restrictions on noise levels, offshore wind farms provide favourable conditions for the development of high-tip-speed wind turbines. In this study, the multi-objective optimization is presented for a 5MW wind turbine design and the effects of high tip speed on power output, cost and noise are analysed. In order to improve the convergence and efficiency of optimization, a novel type of gradient-based multi-objective evolutionary algorithm is proposed based on uniform decomposition and differential evolution. Optimization examples of the wind turbines indicate that the new algorithm can obtain uniformly distributed optimal solutions and this algorithm outperforms the conventional evolutionary algorithms in convergence and optimization efficiency. For the 5MW wind turbines designed, increasing the tip speed can greatly reduce the cost of energy (COE). When the tip speed increases from 80m/s to 100m/s, under the same annual energy production, the COE decreases by 3.2% in a class I wind farm and by 5.1% in a class III one, respectively, while the sound pressure level increases by a maximum of 4.4dB with the class III wind farm case.