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A compact four-element ultra-wideband (UWB) multiple-input–multiple-output (MIMO) antenna with dual polarization and dual-notched capabilities was developed and fabricated. The MIMO antenna is composed of four orthogonally placed half-cutting UWB antenna elements. This orthogonal placement improves the isolation. Furthermore, an L-shaped slot and a continuous bending slot are etched to realize the band-rejection function in the WiMAX and WLAN bands. The result shows that the antenna achieved operating bands of 2.9–16.5 GHz (140.2%, S11 < −10 dB), fully covering the UWB (3.1–10.6 GHz). The port isolation is greater than 23 dB in the frequency band of interest, excluding two rejected bands. Moreover, the MIMO antenna has excellent diversity performance, such as a low envelope correlation coefficient (<0.004), high diversity gain (approximately 10 dB), and good omnidirectional radiation characteristics.
This paper studies the optimal allocation policy of a coherent system with independent heterogeneous components and dependent subsystems, the systems are assumed to consist of two groups of components whose lifetimes follow proportional hazard (PH) or proportional reversed hazard (PRH) models. We investigate the optimal allocation strategy by finding out the number $k$ of components coming from Group A in the up-series system. First, some sufficient conditions are provided in the sense of the usual stochastic order to compare the lifetimes of two-parallel–series systems with dependent subsystems, and we obtain the hazard rate and reversed hazard rate orders when two subsystems have independent lifetimes. Second, similar results are also obtained for two-series–parallel systems under certain conditions. Finally, we generalize the corresponding results to parallel–series and series–parallel systems with multiple subsystems in the viewpoint of the minimal path and the minimal cut sets, respectively. Some numerical examples are presented to illustrate the theoretical findings.
The present work was performed to analyse the association of dietary patterns with glycaemic control (Hb A1c < 7 %) in a large group of Chinese adults aged between 45 and 59 years.
Habitual dietary intakes in the preceding 12 months were assessed by well-trained interviewers using a validated semi-quantitative FFQ. Factor analysis with principal component method was used to obtain the dietary patterns, and the associations between dietary patterns and glycaemic control were determined using multivariable logistic regression models. Poor glycaemic control was defined as HbA1c ≥ 7·0.
Despite decades of research, data on the relationship between dietary patterns and glycaemic control (HbA1c < 7 %) in China are sparse.
A total of 1739 participants aged 45–59 years from Hangzhou were included in the final analysis.
Three dietary patterns were ascertained and labelled as traditional southern Chinese, Western and grains-vegetables patterns. After controlling of the possible confounders, participants in the highest quartile of Western pattern scores had greater OR for HbA1c ≥ 7·0 (OR = 1·05; (95 % CI 1·000, 1·095); P = 0·048) than did those in the lowest quartile. Compared with those in the lowest quartile of grains-vegetables pattern, participants in the highest quartile had lower OR for HbA1c ≥ 7·0 (OR = 0·82; (95 % CI 0·720, 0·949); P = 0·038). Besides, no significant relationship between the traditional southern Chinese pattern and HbA1c ≥ 7·0 was observed (P > 0·05).
This study indicated that the Western pattern was associated with a higher risk, and the grains-vegetables pattern was associated with a lower risk for HbA1c ≥ 7·0. Future prospective studies are needed to confirm our findings.
To explore the characteristics of the mitochondrial genome (mitogenome) of the squeaking silkmoths Rhodinia, a genus of wild silkmoths in the family Saturniidae of Lepidoptera, and reveal phylogenetic relationships, the mitogenome of Rhodinia fugax Butler was determined. This wild silkmoth spins a green cocoon that has potential significance in sericulture, and exhibits a unique feature that its larvae can squeak loudly when touched. The mitogenome of R. fugax is a circular molecule of 15,334 bp long and comprises 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and an A + T-rich region, consistent with previous observations of Saturniidae species. The 370-bp A + T-rich region of R. fugax contains no tandem repeat elements and harbors several features common to the Bombycidea insects, but microsatellite AT repeat sequence preceded by the ATTTA motif is not present. Mitogenome-based phylogenetic analysis shows that R. fugax belongs to Attacini, instead of Saturniini. This study presents the first mitogenome for Rhodinia genus.
Nutritional Risk Screening index is a standard tool to assess nutritional risk, but epidemiological data are scarce on controlling nutritional status (CONUT) as a prognostic marker in acute haemorrhagic stroke (AHS). We aimed to explore whether the CONUT may predict a 3-month functional outcome in AHS. In total, 349 Chinese patients with incident AHS were consecutively recruited, and their malnutrition risks were determined using a high CONUT score of ≥ 2. The cohort patients were divided into high-CONUT (≥ 2) and low-CONUT (< 2) groups, and primary outcomes were a poor functional prognosis defined as the modified Rankin Scale (mRS) score of ≥ 3 at post-discharge for 3 months. Odds ratios (OR) with 95 % confidence intervals (CI) for the poor functional prognosis at post-discharge were estimated by using a logistic analysis with additional adjustments for unbalanced variables between the high-CONUT and low-CONUT groups. A total of 328 patients (60·38 ± 12·83 years; 66·77 % male) completed the mRS assessment at post-discharge for 3 months, with 172 patients at malnutrition risk at admission and 104 patients with a poor prognosis. The levels of total cholesterol and total lymphocyte counts were significantly lower in high-CONUT patients than low-CONUT patients (P = 0·012 and < 0·001, respectively). At 3-month post discharge, there was a greater risk for the poor outcome in the high-CONUT compared with the low-CONUT patients at admission (OR: 2·32, 95 % CI: 1·28, 4·17). High-CONUT scores independently predict a 3-month poor prognosis in AHS, which helps to identify those who need additional nutritional managements.
The effects of early thiamine use on clinical outcomes in critically ill patients with acute kidney injury (AKI) are unclear. The purpose of this study was to investigate the associations between early thiamine administration and clinical outcomes in critically ill patients with AKI. The data of critically ill patients with AKI within 48 h after ICU admission were extracted from the Medical Information Mart for Intensive Care III (MIMIC III) database. PSM was used to match patients early receiving thiamine treatment to those not early receiving thiamine treatment. The association between early thiamine use and in-hospital mortality due to AKI was determined using a logistic regression model. A total of 15 066 AKI patients were eligible for study inclusion. After propensity score matching (PSM), 734 pairs of patients who did and did not receive thiamine treatment in the early stage were established. Early thiamine use was associated with lower in-hospital mortality (OR 0·65; 95 % CI 0·49, 0·87; P < 0·001) and 90-d mortality (OR 0·58; 95 % CI 0·45, 0·74; P < 0·001), and it was also associated with the recovery of renal function (OR 1·26; 95 % CI 1·17, 1·36; P < 0·001). In the subgroup analysis, early thiamine administration was associated with lower in-hospital mortality in patients with stages 1 to 2 AKI. Early thiamine use was associated with improved short-term survival in critically ill patients with AKI. It was possible beneficial role in patients with stages 1 to 2 AKI according to the Kidney Disease: Improving Global Outcomes criteria.
The effect of vitamin D (VD) on the risk of preeclampsia (PE) is uncertain. Few of previous studies focused on the relationship between dietary VD intake and PE risk. Therefore, we conducted this 1:1 matched case–control study to explore the association of dietary VD intake and serum VD concentrations with PE risk in Chinese pregnant women. A total of 440 pairs of participants were recruited during March 2016 to June 2019. Dietary information was obtained using a seventy-eight-item semi-quantitative FFQ. Serum concentrations of 25(OH)D2 and 25(OH)D3 were measured by liquid chromatography–tandem MS. Multivariate conditional logistic regression was used to estimate OR and 95 % CI. Restricted cubic splines (RCS) were plotted to evaluate the dose–response relationship of dietary VD intake and serum VD concentrations with PE risk. Compared with the lowest quartile, the OR of the highest quartile were 0·45 (95 % CI 0·29, 0·71, Ptrend = 0·001) for VD dietary intake and 0·26 (95 % CI 0·11, 0·60, Ptrend = 0·003) for serum levels after adjusting for confounders. In addition, the RCS analysis suggested a reverse J-shaped relationship between dietary VD intake and PE risk (P-nonlinearity = 0·02). A similar association was also found between serum concentrations of total 25(OH)D and PE risk (P-nonlinearity = 0·02). In conclusion, this study provides evidence that higher dietary intake and serum levels of VD are associated with the lower risk of PE in Chinese pregnant women.
Residual negative symptoms and cognitive impairment are common for chronic schizophrenia patients. The aim of this study was to investigate the efficacy of a mindfulness-based intervention (MBI) on negative and cognitive symptoms of schizophrenia patients with residual negative symptoms.
In this 6-week, randomized, single-blind, controlled study, a total of 100 schizophrenia patients with residual negative symptoms were randomly assigned to the MBI or control group. The 6-week MBI group and the control group with general rehabilitation programs maintained their original antipsychotic treatments. The scores for the Positive and Negative Syndrome Scale (PANSS), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), and the Symptom Checklist 90 (SCL-90) were recorded at baseline and week 6 to assess psychotic symptoms, cognitive performance, and emotional state, respectively.
Compared with general rehabilitation programs, MBI alleviated the PANSS-negative subscore, general psychopathology subscore, and PANSS total score in schizophrenia patients with residual negative symptoms (F = 33.77, pBonferroni < 0.001; F = 42.01, pBonferroni < 0.001; F = 52.41, pBonferroni < 0.001, respectively). Furthermore, MBI improved RBANS total score and immediate memory subscore (F = 8.80, pBonferroni = 0.024; F = 11.37, pBonferroni = 0.006), as well as SCL-90 total score in schizophrenia patients with residual negative symptoms (F = 18.39, pBonferroni < 0.001).
Our results demonstrate that MBI helps schizophrenia patients with residual negative symptoms improve clinical symptoms including negative symptom, general psychopathology symptom, and cognitive impairment.
Together with increasingly saturated and commoditized global markets companies are driven to shift their business focus, adopting a strategy where customer perceived value is in the spotlight, and where products are bundled with services to offer Product-Service Systems (PSS).
In this research we study the emergence of PSS solutions in the Chinese market via a selected case study on e-scooters, based on the governmental decision to ban fossil-fuel scooters in the late 90s and how this has spurred both a fossil-to-electric transformation and a product-to-function transformation.
As seen in this research PSS is also an approach that is working well in the Eastern society and especially in China, based on governmental policies. It is gradually being adopted and applied in local industries significantly by China's leading internet companies (Didi, Alibaba etc). The PSS concept represented by e-bike cases in China has gradually penetrated into different industries. With governmental decisions as the key turn-point, it can be seen in practice and development that China's related service industry is using e-bike PSS to carry out the new business model from selling e-bikes to providing service-oriented solutions.
The function and change of global soil carbon (C) reserves in natural ecosystems are key regulators of future carbon-climate coupling. Microbes play a critical role in soil carbon cycling and yet there is poor understanding of their roles and C metabolism flexibility in many ecosystems. We wanted to determine whether vegetation type and climate zone influence soil microbial community composition (fungi and bacteria) and carbon resource preference. We used a biomarker (phospholipid fatty acids, PLFAs), natural abundance 13C and 14C probing approach to measure soil microbial composition and C resource use, along a 1900–4167-m elevation gradient on Mount Gongga (7556 m asl), China. Mount Gongga has a vertical mean annual temperature gradient of 1.2–10.1°C and a diversity of typical vegetation zones in the Tibetan Plateau. Soils were sampled at 10 locations along the gradient capturing distinct vegetation types and climate zones from lowland subtropical-forest to alpine-meadow. PLFA results showed that microbial communities were composed of 2.1–51.7% bacteria and 2.0–23.2% fungi across the elevation gradient. Microbial biomass was higher and the ratio of soil fungi to bacteria (F/B) was lower in forest soils compared to meadow soils. δ13C varied between −33‰ to −17‰ with C3 plant carbon sources dominant across the gradient. Soil organic carbon (SOC) turnover did not vary among three soils we measured from three forest types (i.e., evergreen broadleaved subtropical, mixed temperate, coniferous alpine) and dissolved organic carbon (DOC) turnover decreased with soil elevation. Forest soil microbial PLFA 14C and δ13C measurements showed that forest type and climate were related to different microbial C use. The 14C values of microbial PLFAs i15, a15, 16:1, br17 decreased with elevation while those of C16:0, cyC17, and cyC19 did not show much difference among three forest ecosystems. Bacteria and bacillus represented by C16:1 and brC17 showed considerable microbial C metabolism flexibility and tended to use ancient carbon at higher altitudes. Anaerobes represented by cyC17 and cyC19 showed stronger C metabolism selectivity. Our findings reveal specific C source differences between and within soil microbial groups along elevation gradients.
The prevention, treatment and control of Haemonchus contortus have been increasingly problematic due to its widespread occurrence and anthelmintic resistance. There are very few descriptions of recombinant antigens being protective for H. contortus, despite the success of various native antigen preparations, including Barbervax. We recently identified an H. contortus excretory–secretory antigen, H. contortus adhesion-regulating molecule 1 (HcADRM1), that served as an immunomodulator to impair host T-cell functions. Given the prophylactic potential of HcADRM1 protein as a vaccine candidate, we hereby assessed the efficacies of HcADRM1 preparations against H. contortus infection. Parasitological and immunological parameters were evaluated throughout all time points of the trials, including fecal egg counts (FEC), abomasal worm burdens, complete blood counts, cytokine production profiles and antibody responses. Active vaccination with recombinant HcADRM1 (rHcADRM1) protein induced protective immunity in inoculated goats, resulting in reductions of 48.9 and 58.6% in cumulative FEC and worm burdens. Simultaneously, passive administration of anti-HcADRM1 antibodies generated encouraging levels of protection with 46.7 and 56.2% reductions in cumulative FEC and worm burdens in challenged goats. In addition, HcADRM1 preparations-immunized goats showed significant differences in mucosal and serum antigen-specific immunoglobulin G (IgG) levels, total mucosal IgA levels, haemoglobin values and circulating interferon-γ, interleukin (IL)-4 and IL-17A production compared to control goats in both trials. The preliminary data of these laboratory trials validated the immunoprophylactic effects of rHcADRM1 protein. It can be pursued as a potential vaccine antigen to develop an effective recombinant subunit vaccine against H. contortus under field conditions.
Schizophrenia is a severe and complex psychiatric disorder that needs treatment based on extensive experience. Antipsychotic drugs have already become the cornerstone of the treatment for schizophrenia; however, the therapeutic effect is of significant variability among patients, and only around a third of patients with schizophrenia show good efficacy. Meanwhile, drug-induced metabolic syndrome and other side-effects significantly affect treatment adherence and prognosis. Therefore, strategies for drug selection are desperately needed. In this study, we will perform pharmacogenomics research and set up an individualised preferred treatment prediction model.
We aim to create a standard clinical cohort, with multidimensional index assessment of antipsychotic treatment for patients with schizophrenia.
This trial is designed as a randomised clinical trial comparing treatment with different kinds of antipsychotics. A total sample of 2000 patients with schizophrenia will be recruited from in-patient units from five clinical research centres. Using a computer-generated program, the participants will be randomly assigned to four treatment groups: aripiprazole, olanzapine, quetiapine and risperidone. The primary outcomes will be measured as changes in the Positive and Negative Syndrome Scale of schizophrenia, which reflects the efficacy. Secondary outcomes include the measure of side-effects, such as metabolic syndromes. The efficacy evaluation and side-effects assessment will be performed at baseline, 2 weeks, 6 weeks and 3 months.
This trial will assess the efficacy and side effects of antipsychotics and create a standard clinical cohort with a multi-dimensional index assessment of antipsychotic treatment for schizophrenia patients.
This study aims to set up an individualized preferred treatment prediction model through the genetic analysis of patients using different kinds of antipsychotics.
The density–depth relationship of the Antarctic ice sheet is important for establishing a high-precision surface mass balance model and predicting future ice-sheet contributions to global sea levels. A new algorithm is used to reconstruct firn density and densification rate by inverting monostatic radio wave echoes from ground-operated frequency-modulated continuous wave radar data collected near four ice cores along the transect from Zhongshan Station to Dome A. The inverted density profile is consistent with the core data within 5.54% root mean square error. Due to snow redistribution, the densification rate within 88 km of ice core DT401 is correlated with the accumulation rate and varies greatly over horizontal distances of <5 km. That is, the depth at which a critical density of 830 kg m−3 is reached decreases and densification rate increases in high-accumulation regions but decreases in low-accumulation regions. This inversion technique can be used to analyse more Antarctic radar data and obtain the density distribution trend, which can improve the accuracy of mass-balance estimations.
This paper addresses fixed-time trajectory tracking for a dual-arm free-floating space robot (FFSR) with the large initial errors and bounded uncertainty. A wrist-based trajectory planning method is improved by fixed-time stability to fast eliminate the error caused by singularity. Then, a novel low-chattering and global-nonsingular fixed-time terminal sliding mode control strategy is studied by state approaching angle and switching sliding mode; the practical fixed-reachable Lyapunov stability analysis is presented for a mechanical control system. In the end, the proposed trajectory planning method and controller are combined to improve the tracking accuracy of end-effector to the nanoscale. Simulation results validate the effectiveness of the proposed methodologies.
The association between blood transfusion and ventilator-associated events (VAEs) has not been fully understood. We sought to determine whether blood transfusion increases the risk of a VAE.
Nested case-control study.
This study was based on a registry of healthcare-associated infections in intensive care units at West China Hospital system.
1,657 VAE cases and 3,293 matched controls were identified.
For each case, 2 controls were randomly selected using incidence density sampling. We defined blood transfusion as a time-dependent variable, and we used weighted Cox models to calculate hazard ratios (HRs) for all 3 tiers of VAEs.
Blood transfusion was associated with increased risk of ventilator-associated complication-plus (VAC-plus; HR, 1.47; 95% CI, 1.22–1.77; P <.001), VAC-only (HR, 1.29; 95% CI, 1.01–1.65; P = .038), infection-related VAC-plus (IVAC-plus; HR, 1.78; 95% CI, 1.33–2.39; P < .001), and possible ventilator-associated pneumonia (PVAP; HR, 2.10; 95% CI, 1.10–3.99; P = .024). Red blood cell (RBC) transfusion was also associated with increased risk of VAC-plus (HR, 1.34; 95% CI, 1.08–1.65; P = .007), IVAC-plus (HR, 1.70; 95% CI, 1.22–2.36; P = .002), and PVAP (HR, 2.49; 95% CI, 1.17–5.28; P = .018). Compared to patients without transfusion, the risk of VAE was significantly higher in patients with RBC transfusions of >3 units (HR, 1.73; 95% CI, 1.25–2.40; P = .001) but not in those with RBC transfusions of 0–3 units.
Blood transfusions were associated with increased risk of all tiers of VAE. The risk was significantly higher among patients who were transfused with >3 units of RBCs.
This article discusses the stochastic behavior and reliability properties for the inactivity times of failed components in coherent systems under double monitoring. A mixture representation of reliability function is obtained for the inactivity times of failed components, and some stochastic comparison results are also established. Furthermore, some sufficient conditions are developed in terms of the aging properties of the inactivity times of failed components. Finally, some numerical examples are presented to illustrate the theoretical results.
To examine the association between sleep duration in different stages of life and amnestic mild cognitive impairment (aMCI).
Design, setting, and participants:
A total of 2472 healthy elderly and 505 patients with aMCI in China were included in this study. The study analyzed the association between aMCI and sleep duration in different stages of life.
We compared sleep duration in different stages of life and analyzed the association between Montreal Cognitive Assessment scores and sleep duration by curve estimation. Logistic regression was used to evaluate the association between aMCI and sleep duration.
In the analysis, there were no results proving that sleep duration in youth (P = 0.719, sleep duration < 10 hours; P = 0.999, sleep duration ≥ 10 hours) or midlife (P = 0.898, sleep duration < 9 hours; P = 0.504, sleep duration ≥ 9 hours) had a significant association with aMCI. In the group sleeping less than 7 hours in late life, each hour more of sleep duration was associated with approximately 0.80 of the original risk of aMCI (P = 0.011, odds ratio = 0.80, 95% confidence interval = 0.68–0.95).
Among the elderly sleeping less than 7 hours, there is a decreased risk of aMCI for every additional hour of sleep.
In this paper, a general method for synthesizing dispersive coupling matrix (DCM) of coupled-resonator bandpass filters with the general dispersion is proposed. Compared to the dispersion-less coupling matrix synthesized by classic approaches, the DCM incorporates the identity of the physical realization and provides an accurate description of the filter. Moreover, the DCM can accurately describe the complex resonators and coupling elements with intentional strong dispersion. A DCM consists of two parts: the frequency-invariant part that corresponds to the coupling matrix at the center frequency and the frequency-variant part that reflects the dispersion of the physical realization. By iteratively adjusting the transmission zeros governed by the given filter topology and ignoring the transmission zeros brought by the dispersion, the synthesis method can directly obtain the frequency-invariant part so that the overall DCM leads to an equal-ripple response. To illustrate the general synthesis method, two design examples are presented, which include a filter with unintentional weak dispersion and a filter with intentional strong dispersion. The examples are validated by EM simulation, demonstrating the effectiveness, accuracy, and generality of the proposed synthesis framework. Key words: dispersive coupling matrix, filter synthesis, microwave bandpass filter
The purpose of the current study was to investigate associations between spicy food intake and serum lipids levels in Chinese rural population.
Information on spicy food flavour and intake frequency was obtained using a two-item questionnaire survey. Dietary data were collected using a validated thirteen-item FFQ. Fasting blood samples were collected and measured for total cholesterol (TC), TAG, HDL-cholesterol and LDL-cholesterol. Multivariate linear and logistic regression models were employed to examine the relationship between spicy food and serum lipids levels according to the spicy food flavour and intake frequency, respectively.
A cross-sectional study in Henan Province.
38 238 participants aged 18–79 years old.
Spicy flavour and intake frequency were consistently associated with decreased TC and non-HDL-cholesterol levels but mildly associated with elevated TAG levels. Each level increment in spicy flavour was inversely associated with high TC (OR: 0·91; 95 % CI 0·88, 0·93) and high non-HDL-cholesterol (OR: 0·88; 95 % CI 0·85, 0·91) but positively associated with high TAG (OR: 1·04; 95 % CI 1·01, 1·07). Similarly, 1-d increment in spicy food intake frequency was also inversely associated with high TC (OR: 0·92; 95 % CI 0·91, 0·94) and high non-HDL-cholesterol (OR: 0·91; 95 % CI 0·89, 0·93) but positively associated with high TAG (OR: 1·04; 95 % CI 1·02, 1·06).
Spicy food intake was mildly associated with increased risk of abnormal TAG level, significantly associated with decreased risk of abnormal TC and non-HDL levels. Spicy food intake may be contribute to the management of lipid levels.