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The widespread, rapid evolution of herbicide-resistant weeds is a serious and escalating agronomic problem worldwide. During China’s economic boom, it has become one of the most important herbicide-producing and -consuming countries in the world; meanwhile, herbicide resistance has dramatically increased in the past decade and become a serious threat to its agriculture. Here, following an evidence-based PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) approach, we carried out a systematic review to quantitatively assess the herbicide resistance in China. Multiple weed species, including 26, 18, 11, 9, 5, 5, 4, and 3 species in rice (Oryza sativa L.), wheat (Triticum aestivum L.) soybean [Glycine max (L.) Merr.], corn (Zea mays L.), canola (Brassica napus L.), cotton (Gossypium hirsutum L.)., orchards, and peanut (Arachis hypogaea L.) fields have developed herbicide resistance. Acetolactate synthase (ALS) inhibitors, acetylCoA carboxylase (ACCase) inhibitors and synthetic auxin herbicides are the most prone to resistance and are the leading mode of action, followed by 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase inhibitor and protoporphyrinogen oxidase (PPO) inhibitors herbicides. The lack of alternative herbicides to manage weeds that exhibit cross-resistance or multiple resistance (or both) presents an emerging issue and posts one of the greatest treats challenging the crop production and food safety in China, as well as the world.
Avian nest site selection is crucial to breeding birds especially for large endangered waterbirds. We investigated the population dynamics, nests and breeding habitat selection, offspring numbers and reproductive success rate of Oriental Stork Ciconia boyciana from February to June 2017 in Yellow River Delta National Nature Reserve (YRD NNR), Shandong, China. We measured the characteristic variables of 32 control plots by random selection and 62 nest plots, including 40 nests on power poles, 14 nests on artificial poles and eight nests on pylon poles. We used conditional logistic regression and model-averaging to quantify data and model characteristic variables affecting nest site selection. Our results showed that human disturbance was the main negative factor affecting Oriental Stork’s selection of power pole nests. Meanwhile, distance from highways was the most important variable for the selection of artificial nests. Distance from sightseeing sites was the main explanatory variable that contributed to the selection of pylon nests. Based on our findings, we recommend promoting conservation of this species by reducing human disturbance, such as forbidding use of car horns in nest site areas and providing enough suitable nest sites.
Chinese sturgeon (Acipenser sinensis) is an endangered species, listed as a Grade I protected animal in China. The females rarely successfully develop their gonads from stage II to III in captivity, which handicaps the propagation of cultured Chinese sturgeon. The current study aimed to understand the effects of dietary lipid level on the ovarian development and the related regulation mechanism in female Chinese sturgeon. A 24-month feeding trial was conducted with 10-year-old Chinese sturgeons with ovaries at the developmental stage II, with three experimental diets containing 10, 14 and 18% lipids. Ovary, muscle and serum samples were collected at four time-points (6, 12, 18 and 24 months) for further analyses. Serum metabolomics and ovary transcriptomics analyses were conducted at the 18 months. Results showed that only the 18% lipid diet promoted ovary development to the stage IV. Oocytes at stage II in this group also exhibited higher diameter and more lipid droplets. Serum triglyceride content in the 18% group was significantly higher than in groups 10 and 14% (both at 12 and 18 months). Estradiol content in the group 14% was significantly higher than in 10 and 18% groups, except at 24 months. Metabolomic and transcriptomic results indirectly indicated that 14% of dietary lipids benefited steroid hormone synthesis, while 18% lipid facilitated arachidonic acid metabolism, cholesterol biosynthesis and vitellogenesis, although serum cholesterol content did not vary with the dietary lipid level. In conclusion, 18% dietary lipid is the optimal level for improving gonad development of female Chinese sturgeon.
Many components in diet have regulated oxidative stress, inflammatory reaction and even balance estrogen levels. Because these factors are closely associated with depressive symptoms in postmenopausal women, it is considered that dietary factors are able to prevent and control depressive symptoms. On the other hand, dietary pattern that considers the correlations and synergies between foods and nutrients, is expected to have a greater impact on disease risk. The aim of this study is to evaluate whether dietary patterns are associated with depressive symptoms in Chinese postmenopausal women.
A cross-sectional study of 2051 postmenopausal women (mean age: 58.8±7.4 years) was conducted in Tianjin, China. Dietary consumption was assessed by a valid self-administered food frequency questionnaire. Principal component analysis was used to derive three major dietary patterns: “healthy”, “sweets” and “Traditional Tianjin” from 88 food items. Depressive symptoms were assessed using the Zung Self-Rating Depression Scale, and cut-off point of 48 indicating serious depressive symptoms. The associations between quartile of dietary patterns and depressive symptoms were assessed by using multiple logistic regression analysis.
The multivariable-adjusted odds ratios (95% confidence intervals) of having depressive symptoms for increasing quartile of dietary patterns were as follows: “healthy”, 1.00, 0.79(0.49–1.28), 0.62(0.37–1.04), and 0.57(0.33–0.97); “sweets”,1.00, 0.75(0.42–1.3), 1.08(0.64–1.81) and 1.66(1.03–2.71); “Traditional Tianjin”, 1.00, 1.02(0.58–1.79), 0.96 (0.54–1.71) and 2.53(1.58–4.16), respectively.
The present study demonstrated that a healthy dietary pattern was inversely associated with depressive symptoms. On the contrary, greater adherence to sweets and Traditional Tianjin dietary patterns were associated with a higher prevalence of depressive symptoms.
Evaluation of Cr, Mn, Fe, Zn and Se in humans is challenged by the potentially high within-individual variability of these elements in biological specimens, which are poorly characterised. This study aimed to evaluate their within-day, between-day and between-month variability in spot samples, first-morning voids and 24-h collections. A total of 529 spot urine samples (including eighty-eight first-morning voids and 24-h collections) were collected from eleven Chinese adult men on days 0, 1, 2, 3, 4, 30, 60 and 90 and analysed for these five elements using inductively coupled plasma-MS. Intraclass correlation coefficients (ICC) were utilised to characterise the reproducibility, and their sensitivity and specificity were analysed to assess how well a single measurement classified individuals’ 3-month average exposures. Serial measurements of Zn in spot samples exhibited fair to good reproducibility (creatinine-adjusted ICC = 0·47) over five consecutive days, which became poor when the samples were gathered months apart (creatinine-adjusted ICC = 0·33). The reproducibility of Cr, Mn, Fe and Se in spot samples was poor over periods ranging from days to months (creatinine-adjusted ICC = 0·01–0·12). Two spot samples were sufficient for classifying 60 % of the men who truly had the highest (top 33 %) 3-month average Zn concentrations; for Cr, Mn, Fe and Se, however, at least three specimens were required to achieve similar sensitivities. In conclusion, urinary Cr, Mn, Fe, Zn and Se concentrations showed a strong within-individual variability, and a single measurement is not enough to efficiently characterise individuals’ long-term exposures.
Arid central Asia plays an important role in global climate dynamics, but large uncertainties remain in our understanding of the region's hydroclimate variability during the Late Quaternary. Here we present a new, high-resolution record of lacustrine sediment grain-size and element chemistry from Ebinur Lake, which was used to infer lake conditions and related climate changes in the study region between ca. 39.2 and 3.6 ka. End-member modeling analysis of grain-size data and PCA of elemental data show that lake level fluctuated dramatically from 39.2 to 34.0 ka. Subsequently, Ebinur Lake experienced a high stand from 34.0 to 28.0 ka, under humid climate conditions. The subsequent period, from 28.0 to 12.0 ka, was characterized by lake regression under dry climate conditions, whereas afterward (12.0–3.6 ka), considerably higher lake levels and humid conditions again prevailed. Millennial-scale abrupt climate changes, such as Heinrich events (H3 and H1) and the Younger Dryas, which are documented in the North Atlantic region, are also detected in the sediment record from Ebinur Lake. Comparisons with other sediment records from arid central Asia generally support the claim that climate change in this region was influenced mainly by variations in North Atlantic sea surface temperatures, through the westerlies.
High-peak-power transform-limited narrow-linewidth nanosecond all-fiber lasers are desired in a range of applications. However, their linewidths will be broadened by self-phase modulation (SPM). We propose a novel concept that generates transform-limited laser pulses by temporally shaping the pulse seed. The impact of the pulse shape on SPM-induced spectral broadening was studied numerically and experimentally. It was found theoretically that the square-shape pulsed laser is immune to SPM-induced spectral broadening. Based on this principle, we built a high-peak-power, linearly polarized, square-shape nanosecond all-fiber laser in a master oscillator power amplifier (MOPA) configuration. Stimulated Brillouin scattering (SBS) limited peak powers of 4.02 kW, 5.06 kW, 6.52 kW and 9.30 kW were obtained at pulse widths of 8 ns, 7 ns, 6 ns and 5 ns. Thanks to the square-shape pulsed seed, the linewidths at maximum peak power remained at 129.5 MHz, 137.6 MHz, 156.2 MHz and 200.1 MHz, respectively, close to the transform-limited values of 110.8 MHz, 126.6 MHz, 147.7 MHz and 177.3 MHz.
The timing of the Holocene summer monsoon maximum (HSMM) in northeastern China has been much debated and more quantitative precipitation records are needed to resolve the issue. In the present study, Holocene precipitation and temperature changes were quantitatively reconstructed from a pollen record from the sediments of Tianchi Crater Lake in northeastern China using a plant functional type-modern analogue technique (PFT-MAT). The reconstructed precipitation record indicates a gradual increase during the early to mid-Holocene and a HSMM at ~5500–3100 cal yr BP, while the temperature record exhibits a divergent pattern with a marked rise in the early Holocene and a decline thereafter. The trend of reconstructed precipitation is consistent with that from other pollen records in northeastern China, confirming the relatively late occurrence of the HSMM in the region. However, differences in the onset of the HSMM within northeastern China are also evident. No single factor appears to be responsible for the late occurrence of the HSMM in northeastern China, pointing to a potentially complex forcing mechanism of regional rainfall in the East Asian monsoon region. We suggest that further studies are needed to understand the spatiotemporal pattern of the HSMM in the region.
The seasonality of individual influenza subtypes/lineages and the association of influenza epidemics with meteorological factors in the tropics/subtropics have not been well understood. The impact of the 2009 H1N1 pandemic on the prevalence of seasonal influenza virus remains to be explored. Using wavelet analysis, the periodicities of A/H3N2, seasonal A/H1N1, A/H1N1pdm09, Victoria and Yamagata were identified, respectively, in Panzhihua during 2006–2015. As a subtropical city in southwestern China, Panzhihua is the first industrial city in the upper reaches of the Yangtze River. The relationship between influenza epidemics and local climatic variables was examined based on regression models. The temporal distribution of influenza subtypes/lineages during the pre-pandemic (2006–2009), pandemic (2009) and post-pandemic (2010–2015) years was described and compared. A total of 6892 respiratory specimens were collected and 737 influenza viruses were isolated. A/H3N2 showed an annual cycle with a peak in summer–autumn, while A/H1N1pdm09, Victoria and Yamagata exhibited an annual cycle with a peak in winter–spring. Regression analyses demonstrated that relative humidity was positively associated with A/H3N2 activity while negatively associated with Victoria activity. Higher prevalence of A/H1N1pdm09 and Yamagata was driven by lower absolute humidity. The role of weather conditions in regulating influenza epidemics could be complicated since the diverse viral transmission modes and mechanism. Differences in seasonality and different associations with meteorological factors by influenza subtypes/lineages should be considered in epidemiological studies in the tropics/subtropics. The development of subtype- and lineage-specific prevention and control measures is of significant importance.
AgNPs@g-C3N4 composite was synthesized from Ag-containing sol and g-C3N4 powder by the ultrasonic-assisted self-assembly method. The composite has hierarchical pore size distributions, which will be beneficial to the ion transport with different size. Ag nanoparticles with the size of 5 nm successfully adhere on the surface of g-C3N4. The AgNPs@g-C3N4 composite has excellent specific capacitance and specific power performance for the supercapacitors as an electrode material. The specific capacitance of composite is 4 times greater than that of g-C3N4. It can be ascribed to the introduction of Ag nanoparticles that the internal resistance of the composite is significantly decreased.
A series of metal oxides (MnFeOx, MnCrOx, MnTiOx, and MnFeTiOx) supported on attapulgite (ATP) were synthesized by coprecipitation for the low-temperature selective catalytic reduction (SCR) of NOx with NH3. Then, they were subjected to appropriate characterizations for their properties (XRD, TEM, BET, XPS, etc.). The catalytic activity of MnFeTiOx/ATP catalyst was over 95% NOx conversion within a wide temperature window between of 175 and 300 °C, and 88% N2 selectivity. Moreover, MnFeTiOx/ATP presented excellent potassium resistance relative to the traditional V–W–Ti catalyst, and its denitration performance was significantly improved. The NOx conversion rate could be restored to nearly 90% at 210 °C after removing potassium via washing of K–MnFeTiOx/ATP. In addition, the MnFeTiOx/ATP showed better SO2 resistance and stability than the traditional V–W–Ti catalyst. Therefore, the MnFeTiOx/ATP catalyst has been proved to have broad prospects in NH3-SCR.
Nutrition therapy is considered an important treatment of burn patients. The aim of the study was to delineate the nutritional support in severe burn patients and to investigate association between nutritional practice and clinical outcomes. Severe burn patients were enrolled (n 100). In 90 % of the cases, the burn injury covered above 70 % of the total body surface area. Mean interval from injury to nutrition start was 2·4 (sd 1·1) d. Sixty-seven patients were initiated with enteral nutrition (EN) with a median time of 1 d from injury to first feed. Twenty-two patients began with parenteral nutrition (PN). During the study, thirty-two patients developed EN intolerance. Patients received an average of about 70 % of prescribed energy and protein. Patients with EN providing <30 % energy had significantly higher 28- d and in-hospital mortality than patients with EN providing more than 30 % of energy. Mortality at 28 d was 11 % and in-hospital mortality was 45 %. Multiple regression analysis demonstrated that EN providing <30 % energy and septic shock were independent risk factors for 28- d prognosis. EN could be initiated early in severe burn patients. Majority patients needed PN supplementation for energy requirement and EN feeding intolerance. Post-pyloric feeding is more efficient than gastric feeding in EN tolerance and energy supplement. It is difficult for severe burn patients to obtain enough feeding, especially in the early stage of the disease. More than 2 weeks of underfeeding is harmful to recovery.
Chickenpox is a common acute and highly contagious disease in childhood; moreover, there is currently no targeted treatment. Carrying out an early warning on chickenpox plays an important role in taking targeted measures in advance as well as preventing the outbreak of the disease. In recent years, the infectious disease dynamic model has been widely used in the research of various infectious diseases. The logistic differential equation model can well demonstrate the epidemic characteristics of epidemic outbreaks, gives the point at which the early epidemic rate changes from slow to fast. Therefore, our study aims to use the logistic differential equation model to explore the epidemic characteristics and early-warning time of varicella. Meanwhile, the data of varicella cases were collected from first week of 2008 to 52nd week of 2017 in Changsha. Finally, our study found that the logistic model can be well fitted with varicella data, besides the model illustrated that there are two peaks of varicella at each year in Changsha City. One is the peak in summer–autumn corresponding to the 8th–38th week; the other is in winter–spring corresponding to the time from the 38th to the seventh week next year. The ‘epidemic acceleration week’ average value of summer–autumn and winter–spring are about the 16th week (ranging from the 15th to 17th week) and 45th week (ranging from the 44th to 47th week), respectively. What is more, taking warning measures during the acceleration week, the preventive effect will be delayed; thus, we recommend intervene during recommended warning weeks which are the 15th and 44th weeks instead.
The microstructure evolution of a typical nickel-based superalloy was studied in the strain range of 0.1–0.9 at 1110 °C/0.01 s−1 by using the electron backscattered diffraction technique. It was found that the evolution of recrystallized microstructures, grain boundary characteristics, and textures was closely related to strain level. With the increasing strain level, the fraction of equiaxed dynamic recrystallization (DRX) grains increased significantly at the expense of the large non-recrystallized grains, and there was a decrease in total low angle grain boundaries fraction and a simultaneous increase in the fraction of high angle grain boundaries. In addition, the occurrence of DRX promoted the formation of Σ3 boundaries, and the coherent Σ3 boundaries were much easier to form at the strain above 0.5. On the other hand, 〈100〉 component of the textures became stronger with the increasing strains, and the lack of 〈111〉 orientations can also be observed in the textures at high strains above 0.7.
This study quantified the fatty acid profile with emphasis on the stereo-specifically numbered (sn) 2 positional distribution in TAG and the composition of main phospholipids at different lactation stages. Colostrum milk (n 70), transitional milk (n 96) and mature milk (n 82) were obtained longitudinally from healthy lactating women in Shanghai. During lactation, total fatty acid content increased, with SFA dominating in fatty acid profile. A high ratio of n-6:n-3 PUFA was observed as 11:1 over lactation due to the abundance of linoleic acid in Chinese human milk. As the main SFA, palmitic acid showed absolute sn-2 selectivity, while oleic acid, linoleic acid and α-linolenic acid, the main unsaturated fatty acids, were primarily esterified at the sn-1 and sn-3 positions. Nervonic acid and C22 PUFA including DHA were more enriched in colostrum with an sn-2 positional preference. A total of three dominant phospholipids (phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM)) were analysed in the collected samples, and each showed a decline in amount over lactation. PC was the dominant compound followed by SM and PE. With prolonged breast-feeding time, percentage of PE in total phospholipids remained constant, but PC decreased, and SM increased. Results from this study indicated a lipid profile different from Western reports and may aid the development of future infant formula more suitable for Chinese babies.
The aim of this retrospective study was to investigate the prognostic significance of pre-treatment immunological and nutritional statuses in patients with locally advanced gastric cancer (GC), and to use the risk factors to develop a predictive score. A total of 731 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015 were recruited into this retrospective study. On the basis of univariate and further multivariate Cox regression analyses, decreased pretreatment lymphocyte count (<1·5×109/litre) and prealbumin concentrations (<180 mg/l) were identified to be independently associated with poorer overall survival (OS) and disease-free survival (DFS). Low albumin concentrations (<33 g/l) were identified as an independent risk factor only for OS, but not for DFS. Thereafter, patients who had a decreased prealbumin concentration and lymphocyte count were given a combination of serum prealbumin concentration and lymphocyte count (Co-PaL) score of 2. Patients with only one or neither of these concentrations were given a Co-PaL score of 1 or 0, respectively. Both the OS and the DFS time were inversely related to the Co-PaL scores, and the differences among the three groups were all significant. In contrast, the prognosis did not differ significantly between patients with good nutrition and those with mild to moderate malnutrition according to the prognostic nutritional index. This study indicated that the simple scoring system could accurately predict the prognosis of patients who underwent gastrectomy for stage II/III GC. The score might be helpful in terms of clinical preoperative decision-making.