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High fiber intake is associated with reduced mortality risk in both general and chronic kidney disease populations. However, in dialysis patients such data is limited. Therefore, the association between dietary fiber intake (DFI) and the risk of all-cause and cardiovascular disease (CVD) mortality was examined in this study. A total of 1044 maintenance hemodialysis (MHD) patients from eight outpatient dialysis centers in China were included in this study. Data on DFI was collected using 24-h dietary recalls for three days in a week and was normalized to actual dry weight. The study outcomes included all-cause and CVD mortality. Over a median of 46 months of follow-up, 354 deaths were recorded, of which 210 (59%) were due to CVD. On assessing DFI as tertiles, the CVD mortality risk was significantly lower in patients in tertile 2-3 (≥0.13g/kg/d; hazard ratio [HR]: 0.71; 95% confidence interval [CI]: 0.51-0.97) compared to those in tertile 1 (<0.13g/kg/d). A similar, but non-significant trend was found for the association between DFI (tertile 2-3 vs. tertile 1; HR: 0.83; 95%CI: 0.64-1.07) and all-cause mortality. In summary, higher DFI was associated with lower CVD mortality risk among Chinese patients of MHD. This study emphasized the significance of dietary fiber intake in MHD patients, and provided information that is critical for the improvement of dietary guidelines for dialysis patients.
The high overall plant-based diet index (PDI) is considered to protect against type 2 diabetes in the general population. However, whether the PDI affects gestational diabetes mellitus (GDM) risk among pregnant women is still unclear. We evaluated the association between PDI and GDM risk based on a Chinese large prospective cohort - Tongji Maternal and Child Health Cohort. Dietary data were collected at 13-28 weeks of pregnancy by a validated semi-quantitative food frequency questionnaire. The PDI was obtained by assigning plant food groups positive scores while assigning animal food groups to reverse scores. GDM was diagnosed by a 75g 2-h oral glucose tolerance test at 24-28 weeks of gestation. Logistic regression models were fitted to estimate odds ratios (ORs) of GDM, with associated 95% confidence intervals (CIs), comparing women in different PDI quartiles. Among the total 2,099 participants, 169 (8.1%) were diagnosed with GDM. The PDI ranged from 21.0 to 52.0 with a median (IQR, interquartile range) as 36.0 (33.0-39.0). After adjusting for social-demographic characteristics and lifestyle factors etc., the participants with the highest quartile of PDI were associated with 57% reduced odds of GDM compared with women in the lowest quartile of PDI (Adjusted OR 0.43; 95% CI, 0.24-0.77; P for trend = 0.005). An IQR increment in PDI was associated with 29% decreased odds of GDM (Adjusted OR 0.71; 95% CI, 0.56-0.90). Findings suggest that adopting a plant-based diet during pregnancy could reduce GDM risk among Chinese women, which may be valuable for dietary counseling during pregnancy.
This paper describes an assemblage of diverse floodplain facies of reworked loess (facies b, c) in a Middle Pleistocene monsoonal setting of the Hanzhong Basin, central China. The vertical and lateral sedimentary sequences show changing energy conditions. Apart from the highest energy in the channel facies (facies a), a relatively high energy floodplain environment (facies b) prevailed in waterlogged conditions, with small, laterally migrating (sub)channels. Facies b generally interfingers with aggrading horizontal sheets of overbank deposits in alluvial pools and swamps in a floodplain with much lower energy (facies c), in which phases of stability (soil formation) occasionally interrupted overbank deposition. Reworked loess forms the main part of the floodplain deposits. The paleosols are considered to have been formed under low hydrodynamic conditions in an interglacial environment. These interglacial conditions follow the commonly assumed glacial conditions of channel facies a. The sedimentary successions in the floodplain show a recurrent composition and cyclicity between wet and dry floodplain sedimentation terminated by stability with soil formation. The cyclic rhythm of stacked high- and low-energy floodplain sediments is attributed to varied intensity of different hydrodynamic flooding events that may have been due to changing monsoonal rainfall or simple intrinsic fluvial behavior.
The loess deposits in Shandong Province in eastern China potentially provide valuable insights into past environmental changes. However, their precise provenance and paleoclimatic implications are unclear. We studied three loess sections located in the piedmont of the Central Shandong Mountains (PCSM) and in an offshore island in Bohai Gulf. Both the glacial loess and interglacial paleosol units are characterized by a coarse grain size, indicating a proximal sediment source. Using the “grain size–transport distance” model established for the Chinese Loess Plateau (CLP), the estimated source-sink distance is ~200–300 km for the PCSM loess and ~100–200 km for the coastal loess. This suggests that fluvial deposits of the Yellow River system in the North China Plain and sediments on the adjacent continental shelf are the major provenance for the Shandong loess. In contrast to the CLP, the Shandong loess does not show a consistent pattern of coarse grain size and low magnetic susceptibility values in glacial loess compared with interglacial paleosols, likely due to frequent changes in dust sources caused by diversions of the Yellow River and local hydroclimatic conditions. Nevertheless, the loess-paleosol alternations in the Shandong loess are a product of global glacial–interglacial cycles.
Common vetch (Vicia sativa) is an important forage and green manure crop that is widely cultivated around the world. However, the large number of subspecies and accessions of common vetch has made taxonomic research on this species difficult. Pollen morphology data can provide important evidence in the study of plant phylogeny. Therefore, in this research, light microscopy and scanning electron microscopy were used to observe seven morphological traits of pollens from 22 common vetch accessions, and residual maximum likelihood and pattern analysis was conducted. The results showed that the pollen grains of the 22 accessions were all monad pollen and the polar view revealed three-lobed circular and triangular shapes, while the equatorial view mainly revealed an oblate shape; only one accession showed an oblate spherical shape. All accessions were 3-zonocolporate and the colpus length extended close to the poles. The polar axis length was (19.39 ± 0.97)–(42.12 ± 0.76) μm and the equatorial axis length was (35.97 ± 1.27)–(45.25 ± 0.81) μm. We found that qualitative traits of pollen shape, aperture polar view and ornamentation were highly stable. Among them, polar axis length, equatorial axis length and colpus length and width had significant differences among the accessions. The ratios of the equatorial and polar axes had significant differences among the subspecies. This trait information could be used for the classification and identification of common vetch accessions and subspecies.
Barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] is a problematic weed that grows in rice (Oryza sativa L.) fields. Over-applying herbicide caused environmental pollution and the emergence of resistant weeds, and integrated weed management method can reduce the dependence on herbicides. The growth of E. crus-galli and rice seedlings could be significantly inhibited by high concentrations of fulvic acid (FA, C14H12O8) under flooding conditions (HF, 0.80 g/L) (p < 0.05). In contrast, the growth of seedlings could be promoted by the application of very low-concentration FA (LF, 0.02 g/L). The activities of glutathione S-transferase (GSTs) and antioxidant enzymes, including total superoxide dismutase (T-SOD), peroxidase (POD), and catalase (CAT) in E. crus-galli seedlings were enhanced by LF treatment; while the POD activity was decreased, the GSTs, T-SOD, and CAT activities were not significantly changed by HF treatment. The metabolomic and transcriptomic analyses showed that FA regulated E. crus-galli seedling growth by affecting the synthesis of indole derivatives and flavonoid compounds. Compared with the blank control (CK, 0 g/L), the levels of four indole derivatives were up-regulated under HF treatment, and the indole derivatives mentioned above were slightly down-regulated under LF treatment. The flavonoids, including naringenin, naringenin chalcone, eriodictyol, kaempferol, and epigallocatechin, were down-regulated under HF treatment, and the growth of E. crus-galli was restrained. In contrast, the metabolism and transcription of flavonoids were not significantly changed under LF treatment. Under the addition of 0.80 g/L FA, the growth of newly sprouted E. crus-galli was obviously inhibited, and the growth of rice was significantly promoted after eight days of rice planting (p < 0.05). The application of FA, therefore, might be a potential integrated weed management method to control the damage caused by E. crus-galli in paddy fields.
Hypertension represents one of the most common pre-existing conditions and comorbidities in Coronavirus disease 2019 (COVID-19) patients. To explore whether hypertension serves as a risk factor for disease severity, a multi-centre, retrospective study was conducted in COVID-19 patients. A total of 498 consecutively hospitalised patients with lab-confirmed COVID-19 in China were enrolled in this cohort. Using logistic regression, we assessed the association between hypertension and the likelihood of severe illness with adjustment for confounders. We observed that more than 16% of the enrolled patients exhibited pre-existing hypertension on admission. More severe COVID-19 cases occurred in individuals with hypertension than those without hypertension (21% vs. 10%, P = 0.007). Hypertension associated with the increased risk of severe illness, which was not modified by other demographic factors, such as age, sex, hospital geological location and blood pressure levels on admission. More attention and treatment should be offered to patients with underlying hypertension, who usually are older, have more comorbidities and more susceptible to cardiac complications.
With the rapid rise in the prevalence of non-tuberculous mycobacteria (NTM) diseases across the world, the microbiological diagnosis of NTM isolates is becoming increasingly important for the diagnosis and treatment of NTM disease. In this study, the clinical presentation, species distribution and drug susceptibility of patients with NTM disease visiting the Chongqing Public Health Medical Centre during March 2016–April 2019 were retrospectively analysed. Among the 146 patients with NTM disease, eight NTM species (complex) were identified. The predominant NTM species in these patients were identified to be Mycobacterium abscessus complex (53, 36.3%), M. intracellulare (38, 26%) and M. fortuitum (17, 11.7%). In addition, two or more species were isolated from 7.5% of the patients. Pulmonary NTM disease (142, 97.3%) showed the highest prevalence among the patients. It was observed that 40.1% of the patients with pulmonary NTM disease had chronic pulmonary obstructive disease and bronchiectasis, while 22.5% had prior tuberculosis. Male patients showed more association with the conditions of cough and haemoptysis than the female patients. In an in vitro antimicrobial susceptibility testing, most of the species showed susceptibility to linezolid, amikacin and clarithromycin, while M. fortuitum exhibited low susceptibility to tobramycin. In conclusion, the prevalence of NTM disease, especially that of the pulmonary NTM disease, is common in Southwest China. Species identification and drug susceptibility testing are thus extremely important to ensure appropriate treatment regimens for patient care and management.
In view of many problems associated with the availability of global navigation satellite system (GNSS) signals in high-altitude space, this paper presents a comprehensive and systematic analysis. First, the coverage and strength characteristics of GNSS signals in high-altitude space (i.e., space above the GNSS constellation) are presented, and the visibility of GNSS signals is evaluated by combining these two factors. Second, the geometric configuration and geometric dilution of precision (GDOP) of visible GNSS satellites are analysed. Then, the Doppler shift range of the GNSS signals is deduced based on the dynamic performance of high-altitude spacecraft. Finally, taking GaoFen-4 (GF-4) as the application object, the availability of GNSS signals is simulated and evaluated. GNSS signals in high-altitude space are generally weak, and the visible GNSS satellites are concentrated in the high-elevation range. The combination of main and side lobe signals and compatibility of multiple constellations can increase the number of visible satellites, improve the geometry configuration, reduce GDOP, and thus improve the availability of GNSS signals. The results of this research can provide technical support for the design and development of GNSS receivers suitable for high-altitude space.
The literature on the relationship between foreign aid and institutions has found that the effects of aid vary across different donor characteristics and delivery mechanisms. This article focuses on China's resource-related development projects, which have been considered controversial due to the relative lack of conditionality. By distinguishing between vertical and horizontal dimensions of political accountability, the study finds that China's resource-related projects are particularly detrimental to the accountability of recipient countries' horizontal (legislative and judicial) institutions. These projects are often delivered to resource-rich countries, in the form of packaging access to resources and infrastructure construction, to improve China's own energy access. Local officials may be tempted to weaken horizontal institutions so that the projects can be implemented quickly. Nevertheless, these projects have little effect on vertical accountability, as China has less intention and capacity to fundamentally restrain electoral competition in recipient countries.
Manure and chemical fertilizers have different effects on soil properties, the nitrogen cycle, and crop yield. This study aimed to investigate the effects of different fertilizer applications under the same N input on soil physicochemical properties and soil bacterial communities and to explain the contributions of soil properties to grain yield. Manure substitution of chemical fertilizer was conducted in leaching monitoring systems. The study began in 2009 and sampling was carried out in 2014 and 2016. Three fertilizer treatments with the same total N, P, and K application rates and one control treatment were designed as follows: (1) CK, without nitrogen fertilizer; (2) 100%U, whole nitrogen coming from urea; (3) 100%M, whole nitrogen coming from composted cattle manure; and (4) 50%U + 50%M, half nitrogen from composted cattle manure and half nitrogen from urea. Soil organic carbon (SOC) content was positively correlated with total N (TN), NO3−–N, and NH4+–N contents, the mean weight diameter of soil aggregates, and the Shannon diversity index of bacteria, whereas SOC content was not significantly correlated with grain yield. NO3−–N content was positively correlated with grain yield. Substituting half the amount of chemical fertilizer with manure as a nitrogen source improved soil stability, increased bacterial diversity, and enhanced nitrogen supply, while reducing nitrogen loss from ammonia volatilization and nitrogen leaching. Substituting half the amount of chemical fertilizer with manure as a nitrogen source was a more sustainable way to increase grain yield through a sustainable nitrate supply and to reduce N loss.
In this paper, the generation of relativistic electron mirrors (REMs) and the reflection of an ultra-short laser off this mirrors are discussed, applying two-dimensional particle-in-cell (2D-PIC) simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapidly expanding. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads the resonance between laser and REM. The reflected radiation near this interval and the corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, certain part of the reflected field could be selectively amplified or depressed, leading to the selectively adjusting of the corresponding spectra.
The treatment of relapsed/refractory multiple myeloma (RRMM), a common hematological malignancy, remains a great challenge in China, partially due to the limited accessibility to novel agents and inadequate public health insurance coverage. Ixazomib, a novel oral proteasome inhibitor (PI), was approved by the China Food and Drug Administration (CFDA) for RRMM in 2018. While bortezomib, a traditional PI, is the recommended agent in the clinical guideline for MM. Here, we compared their costs and effectiveness.
RRMM patients who has received an ixazomib-based regimen (at least 2 cycles) were analyzed. Using a propensity score matching method, we generated a control group of RRMM patients who received the bortezomib-based regimen. The criteria included the number of treatment lines, age, and the revised international staging system stage (R-ISS) which representing the disease stage for myeloma, and paired at a ratio of 1:2 (allowing one control to match multiples). The difference in hospitalization stay, grade 3/4 adverse events rates, overall response rate (ORR), mortality during treatment, and treatment costs was then compared.
Nineteen patients received ixazomib and twenty-seven that received bortezomib were included. The ixazomib-group demonstrated a shorter hospital stay (9 days versus 27 days, p < 0.001), lower grade 3–4 adverse events rates (42.1% versus 55.6%, p < 0.001), higher ORR (63.2% versus 48.1%, p = 0.228), and lower mortality rate during treatment (0% versus 7.4%, p = 0.169) than that of bortezomib-group. The ixazomib group had lower total costs (127,620CNY versus 156,424CNY [18,033USD versus 22,103USD], p > 0.05), lower drug costs (98,376CNY versus 103,307CNY [13,901USD versus 14,598USD], p > 0.05), and the lower costs of supportive treatment (5,507CNY versus 14,701 CNY [778USD versus 2,077USD], p < 0.001). Only in terms of self-funded costs, the bortezomib-based regimen was significantly lower (37,127CNY versus 11,521CNY [5,246USD versus 1,628USD], p < 0.001).
Compared with the bortezomib-based regimen, the ixazomib-based regimen has better therapeutic effects on MM patients while saving costs. Hence, it may be preferable for use in the treatment of RRMM in China.
This study aimed at estimating the transmissibility of hepatitis C. The data for hepatitis C cases were collected in six districts in Xiamen City, China from 2004 to 2018. A population-mixed susceptible-infectious-chronic-recovered (SICR) model was used to fit the data and the parameters of the model were calculated. The basic reproduction number (R0) and the number of newly transmitted cases by a primary case per month (MNI) were adopted to quantitatively assess the transmissibility of hepatitis C virus (HCV). Eleven curve estimation models were employed to predict the trends of R0 and MNI in the city. The SICR model fits the reported HCV data well (P < 0.01). The median R0 of each district in Xiamen is 0.4059. R0 follows the cubic model curve, the compound curve and the power function curve. The median MNI of each district in Xiamen is 0.0020. MNI follows the cubic model curve, the compound curve and the power function curve. The transmissibility of HCV follows a decreasing trend, which reveals that under the current policy for prevention and control, there would be a high feasibility to eliminate the transmission of HCV in the city.
Nutrition in early life has a long-term influence on later health. In order to the explore effects of in ovo feeding (IOF) of vitamin C on splenic development, splenic metabolism and apoptosis were detected in embryo, adult chickens and in vitro. A total of 360 fertile eggs were selected and randomly assigned to control (CON) and vitamin C (VC) groups which were injected with saline and vitamin C on embryonic day 11, respectively. Functional enrichment of differentially expressed genes by transcriptome on embryonic day 19 suggested that purine nucleotide metabolism might be a potential pathway for the IOF of vitamin C to regulate spleen development. Additionally, the IOF of vitamin C significantly increased splenic vitamin C content on post-hatch day 21. Meanwhile, the splenic expression of adenosine deaminase, serine/threonine kinase 1 and proliferating cell nuclear antigen was down-regulated, whereas the expression of cysteinyl aspartate specific proteinase 9 was up-regulated in the VC group. On post-hatch day 42, the IOF of vitamin C significantly down-regulated the splenic expression of B-cell lymphoma 2 and increased the mRNA level of cysteinyl aspartate specific proteinase 9. The IOF of vitamin C could regulate the expression of genes related to adenylate metabolism and increased the apoptosis rate in vitro, which is consistent with the result in vivo. In conclusion, the IOF of vitamin C regulated splenic development and maturation by affecting purine nucleotide metabolism pathway and promoting apoptosis.
The orientation between twin boundary (TB) and loading direction may play an intriguing role in the deformation behaviors of twinned metallic materials. In this aspect, its essential effect on the high-entropy alloy (HEA) nanocrystals is elusive. Attention herein is focused on the atomic-scaled deformation mechanisms and fracture behaviors of HEA nanocrystals containing twins of even smaller spacings via a combined approach of in situ tensile tests inside a high-resolution transmission electron microscope and molecular dynamics simulations. The results indicate that the deformation mechanisms (especially dislocation activities) of HEA nanocrystals depend on the load orientation with respect to TBs. Because of the low activation energy and uneven local composition of HEA, the surface acts as an effective dislocation source and, together with Schmid factor, dominate the activated dislocation slip system. The load orientation-dependent TB-dislocation interactions may transform the type of fracture from semi-brittle to ductile. Our results indicate that the deformation mechanisms and the types of fracture in HEA nanocrystals can be controlled by changing the orientation.
Lead-free BaTiO3 (BT)-based multilayer ceramic capacitors (MLCCs) with the thickness of dielectric layers ~9 μm were successfully fabricated by tape-casting and screen-printing techniques. A single phase of the pseudo-cubic structure was revealed by X-ray diffraction. Backscattered images and energy-dispersive X-ray elemental mapping indicated the high quality of MLCCs without observation of interaction, wrapping, or delamination. The relaxor state was confirmed by transmission electron microscopy and temperature-dependent permittivity. Impedance spectroscopy at various temperatures revealed the electrical heterogeneous response for MLCCs with high-resistive electrical components. Improved energy storage performance was obtained by multilayering, comparing with the bulk ceramics. Enhanced recoverable energy density ~6.88 J/cm3 with high efficiency ~90% were realized under an electric field of 820 kV/cm, which is mainly attributed to the intrinsic high-resistivity and relaxor behavior. Furthermore, good temperature (20–85 °C) and frequency stabilities (0.5–50 Hz) were observed in the MLCCs, which are attractive for pulsed power applications.
As strict measures were taken, the COVID-19 epidemic has been gradually brought under control. As a port city, Shanghai’s main problem has shifted from treating local cases to preventing foreign imports. To prevent the re-outbreak of COVID-19 caused by imported cases, the Shanghai government has set up central isolation sites for all people entering the country from abroad to be placed under medical observation. This report describes how to set up central isolation sites and run it effectively. We put isolation sites in transformed hotels, arranged personnel according to a huge data network, and set up specific procedures to manage guests. The epidemic situation in Shanghai has confirmed the feasibility and effectiveness of the methods that other jurisdictions can adapt for their use.