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Bridge influence lines (BILs) and bridge influence surfaces (BISs) are inherent static parameters of bridges which can be extracted from moving vehicle-induced bridge responses. Compared with dynamic parameters, these parameters are directly related to the stiffness and internal forces in each cross-section of a bridge therefore can be considered as an effective bridge metamodel. To accelerate the engineering practice of BIL- and BIS-based bridge evaluation, this paper first briefly reviews the current BIL and BIS field test and identification methods. Then, the bridge evaluation guidelines of China and the United States are introduced as the basis of the evaluation methods. Engineering application scenarios for bridge evaluation, including permit load verification, performance degradation checking, and load carrying capacity evaluation, are summarized, and a multiple-scenario bridge evaluation method is established. At the end of this paper, an evaluation example of a four-span continuous bridge is presented to illustrate the application procedure and verify the effectiveness of the proposed method. The outcomes of this paper provide a promising application method of field test BILs and BISs, which may help bridge engineers more effectively use these parameters in engineering practice. [ABSTRACT FROM AUTHOR]

Carbonatite intrusions host the world's most important light rare earth element (LREE) deposits, and their formation generally requires extraordinary fertile sources, magmatic evolution, and hydrothermal events. However, carbonatitic magma evolution, particularly the role of fractional crystallization and contamination from silicate rocks in REE enrichment, remains enigmatic. The Maoniuping world-class REE deposit in southwestern China, is an ideal target to decipher magmatic evolution and related REE enrichment as it shows continuous textual evolution from medium- to coarse-grained calcite carbonatite (carbonatite I) at depth, to progressively pegmatoidal calcite carbonatite (carbonatite II) at shallow levels. In both types of calcite carbonatites, four generations of calcite can be classified according to petrographic and geochemical characteristics. Early-crystalizing calcite (Cal-I and Cal-II) are found in carbonatite I and exhibit equigranular and a polygonal mosaic textures, while late calcites (Cal-III and Cal-IV) in carbonatite II are large-size oikocrysts (>0.5 mm in length) with strain-induced undulatory extinction and bent twinning lamellae. All these generations of calcite yield similar, near-chondritic, Y/Ho ratios (26.6–28.1) and are inferred to be of magmatic origin. Remarkably, gradual enrichment of MgO, FeO and MnO from Cal-I to Cal-IV is coupled with a significant increase in REE contents (~800 to 2000 ppm), with LREE-rich and gentle-to-steep chondrite-normalized REE patterns ((La/Yb)N = 3.1–26.8 and (La/Sm)N = 0.9–3.9, respectively). Such significant REE enrichment is ascribed to protracted magma fractional crystallization with initial low degree of fractional crystallization (fraction of melt remining (F) = ~0.95) evolving to late stage (F = 0.5–0.6) by formation of abundant calcite cumulates. Differential LREE and HREE behavior during magma evolution largely depend on separation of phlogopite, amphibole, and clinopyroxene from the carbonatitic melt, which is indicated by progressively elevated (La/Yb)N ratios ranging from 3.1 to 26.8. The four generations of calcite have significantly different C and Sr isotopic compositions with δ13CV-PDB decreasing from −3.28 to −9.97‰ and 87Sr/86Sr increasing from 0.70613 to 0.70670. According to spatial relations and petrographic observations, the relative enrichment of δ13C and depletion in 87Sr/86Sr ratios of Cal-I and Cal-II show primary isotopic characteristics inherited from initial carbonatitic magma. By contrast, the variable Sr and C isotopic compositions of Cal-III and Cal-IV are interpreted as the results of contamination by components derived from silicate wall rocks and loss of CO2 by decarbonation reactions. To model such contamination processes, Raleigh volatilization and Monte Carlo simulation have been invoked and the model results reveal that carbonatitic melt-wall rock interaction requires 40% radiogenic Sr contamination from silicate rocks and 35% CO2 degassing from carbonatitic melt. Moreover, positive correlations between decreasing δ13C values and increasing REE contents, together with bastnäsite-(Ce) precipitation, indicate further REE accumulation during the contamination processes. In summary, alongside REE-rich magma sources, the extent of fractional crystallization and contamination during carbonatitic magma evolution are inferred to be important mechanisms in terms of REE enrichment and mineralization in carbonatite-related REE deposits worldwide. [ABSTRACT FROM AUTHOR]

A preterm infant with birth weight 1,550 g had an intravenous foreign body between the external iliac vein and the common iliac vein, which accidentally happened during peripheral intravascular central catheter insertion by the Seldinger technique. The infant initially received conservative management and close monitoring. Antibiotics were administered 4 weeks to treat culture positive sepsis and meningitis. The infant was clinically stable till the cannula fragment migrated to the heart 34 days later. At that time, his weight was 2,200 g, and he was full fed. The cannula fragment was retrieved by emergency interventional radiology via the right femoral access, with no complications. The infant was discharged at 45 days of age and closely followed up post-discharge. He is currently 6 months old, with normal development. This is the first case of successful percutaneous retrieval of an intracardiac intravenous cannula fragment via femoral access in a premature infant in China. [ABSTRACT FROM AUTHOR]

Background: China incurs an extremely low treatment coverage of multidrug-resistant tuberculosis (MDR-TB). This study aimed to understand the experience of MDR-TB patients on quality of health care, and the clinical impact through an up to six-year follow-up. Methods: Cohorts of MDR-TB patients were built in TB/MDR-TB designated hospitals in four regions of China from 2014 to 2015. Patients were followed up during treatment course, and yearly confirmation afterward until 2019. Delay in MDR-TB diagnosis and treatment was calculated upon bacteriological confirmation and treatment initiation. Risk factors for unfavourable outcomes were identified by multivariate logistic regression. Results: Among 1168 bacteriological-positive TB patients identified from a 12-million population, 58 (5.0%) MDR-TB cases were detected. The median delay for MDR-TB diagnosis was 90.0 days, with 13.8% having a delay above 180.0 days. MDR-TB treatment was only recommended to 19 (32.8%) participants, while the rest continued with regimen for drug-susceptible TB. In MDR-TB treatment group, 36.8% achieved treatment success, while the others had incomplete treatment (21.1%), loss to follow-up (36.8%) and TB relapse (5.3%). For non-MDR-TB treatment group, 33.3% succeeded, 25.6% relapsed, 2.6% failed, 23.1% died, and 15.4% were lost to follow-up. Overall, only 35.7% (20/56) of detected MDR-TB patients had favourable outcomes and higher education level was positively associated with it (adjusted odds ratio [aOR]: 3.60, 95% confidence interval [CI]: 1.04–12.5). Conclusions: A large proportion of patients did not receive MDR-TB treatment and had unfavourable outcomes. Delayed MDR-TB diagnosis resulted in poor quality of MDR-TB care. Rapid diagnosis, regulated patient management and high-quality MDR-TB treatment should be enhanced in China. [ABSTRACT FROM AUTHOR]

Air pollution events frequently occur in China during the winter. Most investigations of pollution studies have focused on the physical and chemical properties of PM2.5. Many of these studies have indicated that PM2.5 exacerbates asthma or eosinophil inflammation. However, few studies have evaluated the relationship between bacterial loads in PM2.5, and especially pathogenic bacteria and childhood asthma. Airborne PM2.5 samples from heavily polluted air were collected in Hangzhou, China between December 2014 and January 2015. PM2.5 and ovalbumin (OVA) were intratracheally administered twice in 4-week intervals to induce the allergic pulmonary inflammation in adolescent C57/BL6 mice. PM2.5 exposure caused neutrophilic alveolitis and bronchitis. In the presence of OVA, the levels of the Th2 cytokines IL-4, IL-12, and IL-17 were significantly increased in bronchoalveolar lavage fluids (BALF) after PM2.5 exposure, while eosinophil infiltration and mucin secretion were also induced. In addition to adjuvant effects on OVA-induced allergic inflammation, PM2.5 exposure also led to the maturation of dendritic cells. These results suggest that PM2.5 exposure may aggravate lung eosinophilia and that PM2.5-bound microbial can exacerbate allergic and inflammatory lung diseases. [ABSTRACT FROM AUTHOR]

Due to the important contribution of nitrous acid (HONO) to OH radicals in the atmosphere, various technologies have been developed to measure HONO. Among them, wet denuder/ion chromatography (WD/IC) is a widely used measurement method. Here, we found interferences with HONO measurements by WD/IC based on a comparison study of concurrent observations of HONO concentrations using a WD/IC instrument (Monitorfor AeRosols and Gases in ambient Air, MARGA) and long-path absorption photometer (LOPAP) at the Station for Observing Regional Processes of the Earth System (SORPES) in eastern China. The measurement deviation of the HONO concentration by the MARGA instrument, as a typical instrument of WD/IC, is affected by two factors. One is the change in denuder pH influenced by acidic and alkaline gases in the ambient atmosphere, which can affect the absorption efficiency of HONO by the wet denuder to underestimate the HONO concentration up to 200 % in lowest pH. The other is the reaction of NO2 oxidizing SO2 to form HONO in the denuder solution to overestimate the HONO concentration, which can be improved up to 400 % in denuder solutions with highest pH values due to ambient NH3. These processes are in particulate important in polluted east China, where is suffered from the high concentrations of SO2, NH3 and NO2. The overestimation induced by the reaction of NO2 and SO2 is expected to be growing important with the potentially increased denuder pH due to the decrease of SO2. We further established a method to correct the HONO data measured by a WD/IC instrument such as the MARGA. In case a large amount WD/IC techniques based instruments are deployed with the main target to monitor the water soluble composition of PM2.5, our study can help to obtain a long-term multi-sites database of HONO to assess the role of HONO in atmospheric chemistry and air pollution in east China. [ABSTRACT FROM AUTHOR]

The model of the mineralization and ore-forming fluid evolution in the Maoniuping deposit, showing that the ore fluid rich in Na, K, (SO 4)2−, Cl−, F−, REE and CO 2 , derived from carbonatite magma which was formed by melting of REE-refertilized metasomatic sub-continental lithospheric mantle (SCLM). The ore fluid was a high-temperature (>800 °C), high-pressure, and high-salinity magmatic fluids and evolved into a medium- to high-temperature (260–480 °C), high-pressure (200–300 MPa), moderate- to high-salinity (9.4–47.8 wt% NaCl equiv), accompanied with immiscibility in hydrothermal stage. Ultimately, main REE mineralization occurred at Fluid low temperature (167–240 °C), pressure (<500 bars), and salinity (8–11 wt%) by fluid cooling and mixing with meteoric water. • The ore-forming fluids in Maoniuping are rich in Na+, K+, (SO 4)2−, Cl−, F−, CO 2 and REE. • Immiscibility is vital before the mineralization and constrained to 310–350 °C, 2.0–2.4 kbar. • Fluid cooling, mixing with meteoric water and increased pH are main mechanisms for REE precipitation. • The fenitization-REE-bearing mineral zonation formed from about 480 to 200 °C. Carbonatite-related rare-earth element (REE) deposits (CARDs) are the major global source of REEs. The ore-forming fluids of CARDs usually comprise multiple components and record complicated evolutions. The Maoniuping REE deposit, located in the eastern Tibetan Plateau, is the second-largest CARD in China and contains total reserves of 3.17 Mt of light rare-earth oxides (REOs). Geochronological and geological data show that the deposit was formed at ∼25 Ma and was only moderately affected by tectonic and hydrothermal activities, thereby allowing us to study the evolution of ore fluids as well as the mechanisms of REE mineralization. The Maoniuping REE deposit is spatially associated with a carbonatite–syenite complex and includes two sections: Guangtoushan and Dagudao. The Dagudao section is the main focus of exploration and hosts well-developed vein systems. In the uppermost vein system, minerals are zoned from the syenite wall-rock contact to the vein centers in the order of biotite, aegirine-augite, arfvedsonite, calcite, quartz, barite, fluorite, and bastnäsite-(Ce). Based on geological observations and the petrography of fluid inclusions, the mineralization processes are classified into magmatic, pegmatitic, hydrothermal I, hydrothermal II, and REE stages. The inclusions in these stages include melt (M), melt–fluid (M–L), pure CO 2 (C), aqueous–CO 2 (L–C), aqueous–CO 2 with crystals (L − C + S), liquid–vapor aqueous with crystals (L − V + S), and liquid–vapor (L–V) type inclusions. The magmatic stage is marked by a carbonatite–syenite complex with minor bastnäsite-(Ce), whereas the pegmatitic stage consists of coarse-grained calcite, barite, fluorite, and quartz that contain M, M–L, and L–C type inclusions with a fluid system of NaCl–Na 2 SO 4 –H 2 O–CO 2 at high temperature (>600 °C) and high salinity (>45 wt% NaCl equiv.). The hydrothermal I stage is characterized by fenitization and is marked by aegirine-augite and arfvedsonite containing abundant L–V and few L–C type inclusions. This stage is characterized by high temperatures (∼480 °C) and moderate salinity (10.2–17.9 wt% NaCl equiv.), with a fluid system of NaCl–Na 2 SO 4 –H 2 O and minor CO 2 and CH 4 + C 2 H 6. The hydrothermal II stage is dominated by L–C, L − C + S, L − V + S, and L–V type inclusions that are hosted in barite, calcite, fluorite, and quartz, and formed at moderate to high temperatures (260–350 °C), with a wide range of salinity (9.4–47.8 wt% NaCl equiv.), a fluid system of NaCl–Na 2 SO 4 –CO 2 –H 2 O, and abundant CH 4 + C 2 H 6. During the REE stage, pervasive bastnäsite-(Ce) containing abundant L–V type and few L–C type inclusions crystallized under low temperatures (160–240 °C) and low salinities (8.8–13.1 wt% NaCl equiv.) with a fluid system of NaCl–H 2 O and minor CO 2 and CH 4 + C 2 H 6. The results of ion-chromatographic analysis show that the ore fluids are rich in Na+, K+, Cl−, F−, and (SO 4)2−, and have low Cl−/(SO 4)2− ratios (0.78–2.00), showing a marked contrast with the fluids of granite-related REE deposits (Cl−/(SO 4)2− > 50) and a similarity to subcontinental lithospheric mantle (SCLM). The δD and δ18O fluid values and the high N 2 /Ar ratios indicate that the ore fluids originated from carbonatitic magma and were dominated by magmatic water during the hydrothermal I stage, whereas magmatic and meteoric water co-existed during the hydrothermal II and REE stages. Moreover, the higher ratios of CO 2 /N 2 (9–64) and CO 2 /CH 4 (17–472) and the higher concentrations of CO 2 , CH 4 , C 2 H 6 , and N 2 in the hydrothermal II stage compared with the hydrothermal I stage are attributed to intense immiscibility that resulted from decompression and is constrained to temperatures of 310–350 °C and pressures of 2.0–2.4 kbar. In contrast, microthermometric data and low CH 4 , C 2 H 6 , and N 2 contents for the REE stage show that fluid cooling and mixing with meteoric water played an important role during the intensive mineralization of this stage, which occurred under shallow open-system conditions at temperatures of ∼200 °C and pressures of <0.5 kbar. The mineral assemblages, together with experimental petrology results, suggest that the REE transport capability of the hydrothermal fluids was due to the high contents of (SO 4)2−, Cl−, and F− complexes. In addition, CO 2 that separates during immiscibility is known to act as a buffer that constrains the pH of ore fluids. Thus, immiscibility during the hydrothermal II stage could have provided favorable conditions for the migration of REEs. The subsequent cooling of fluids, the involvement of meteoric water, and increased fluid pH, favored the precipitation of REEs in the Maoniuping deposit. [ABSTRACT FROM AUTHOR]

Basing on the theoretical model and empirical analysis, this paper provides a discussion of the hedging effectiveness between the stock market and index future market under the imperfect market conditions. In theoretical analysis, the relation of market imperfection with market microstructure noise and hedging effectiveness is established. In empirical analysis, one approach based on nonparametric estimation is established and applied to real data. The reasonableness of model assumptions and the correction of model conclusions are verified by using 5-minute frequency intra data. Both theoretical and empirical analyses show that the higher the degree of market imperfection, the more necessary to consider the impact of market microstructure noise when using stock index futures to hedge the stock market risk. The empirical results also show that there exists a high degree of imperfection between stock market and stock index future market, but the degree of imperfection has a decreasing trend. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to compare the levels of serum anti-cyclic citrullinated peptide (anti-CCP) antibodies in patients with juvenile idiopathic arthritis (JIA) and adult rheumatoid arthritis (RA) and to discuss the clinical value of these antibodies in the diagnosis of JIA. Patients and methods: This study was performed at the Capital Institute of Pediatrics in Beijing between February 2009 and December 2009. The levels of serum anti-CCP antibodies in 72 patients with JIA (33 boys, 39 girls; mean age 7.6±3.9 years; range 2 to 15.9 years), 65 patients with RA (14 boys, 51 girls; mean age 47±14.3 years; range 17 to 75 years), and 22 healthy children (10 boys, 12 girls; mean age 14.1±0.4 years; range 6.1 to 15.7 years) were measured using an enzyme-linked immunosorbent assay (ELISA). The obtained data along with the clinical data were analyzed. Results: The anti-CCP antibody positive rates for the JIA and RA groups were 12.5% and 73.85%, respectively, whereas the rate for the control group was 0% (p<0.001). The anti- CCP antibody positive rates of the polyarticular, oligoarticular, and systemic JIA groups were 31.25%, 14.8% and 0%, respectively (p<0.001). The rheumatoid factor (RF) positive rates, joint destruction rates, and mean disease courses of the positive and negative anti-CCP antibody groups were 66.7% versus 7.9% (chi-square=118.778, p<0.001), 33.3% versus 6.3% (chi-square=124.778, p<0.001), and 18.1 months versus 13.7 months (t=0.606, p=0.546), respectively. Conclusion: The anti-CCP antibody positive rate in patients with JIA is lower than for patients with RA. However this rate varies significantly according to the subtypes of JIA. Positive anti-CCP antibodies often indicate severe joint destruction. [ABSTRACT FROM AUTHOR]

Carbonatites host the world's most important rare earth element (REE) resources. The origins of REE mineralization in carbonatite-related deposits, particularly the role of hydrothermal fluids in REE mobilization and mineralization, remain enigmatic. The Cenozoic Mianning–Dechang REE belt in eastern Tibet is one of the largest REE production regions worldwide, and is an ideal area for investigating REE mineralization. Geological investigations and fluid inclusion studies suggest that ore fluids in this belt evolved from hydrothermal stage I (fenitization at high temperatures of ~480 °C) to hydrothermal stage II (calcite, quartz, barite, and fluorite crystallization at temperatures of 300–350 °C and salinities of ~20 wt% NaCl equiv.), and then to the REE mineralization stage (temperatures of ~200 °C and low salinities of ~9 wt% NaCl equiv.). The bulk fluid compositions demonstrate that the ore fluids contained significant amounts of alkalis (up to 5 wt% Na + K), halogens (up to 12 wt% Cl; up to 7 wt% F), sulfate (>2 wt% SO 4 2−), Ba (>1123 ppm), Sr (>1120 ppm), and REEs (>5 wt%). Chondrite-normalized REE patterns of these fluids are light REE-enriched and exhibit moderate depletion in Eu ([Eu/Eu⁎ CN = 0.85 ± 0.08), similar to the carbonatites and nordmarkites. These fluid characteristics and plots of Rb/Na vs. K/Na and Mn vs. Na suggest that the ore fluids in the Mianning–Dechang REE belt were derived from a late-stage alkaline–carbonatitic magma. High concentrations of Cl−, F−, SO 4 2−, and REEs, and the absence of REE fluoride (REEF 3) and fluorite (CaF 2), suggest that the ore fluids in hydrothermal stage I were a high-temperature, SO 4 2−-rich (>2 wt%), and acidic fluid system (pH < 3.5). In this system, chloride REE complexes were predominant over fluoride and sulfate REE complexes, which resulted in efficient transport of REEs. Sulfate species were predominant in hydrothermal stage II at temperatures of 260–350 °C and a pH between 3.5 and 5.2. The higher pH and fluid cooling from hydrothermal stage I to hydrothermal stage II caused an increase in F−, which in turn lowered fluid REE concentrations, owing to the formation of REE-rich fluorite. This suggests that F− was a depositional ligand in hydrothermal stage II. Continued fluid cooling (~200 °C) and increasing pH (~6), combined with the precipitation of barite and fluorite in the REE mineralization stage, destabilized the REE complexes because of the decreasing concentrations of SO 4 2−, Cl−, and F−, which thus led to widespread REE deposition. A review of different-sized deposits in the Mianning–Dechang REE belt indicates that appreciable amounts of SO 4 2−, Cl−, REEs, CO 2 , and particularly F− and alkalis in fluids, along with a high fluid exsolution temperature, represent the ideal conditions for potential REE mineralization in a carbonatite-related setting. Ore fluids in the Mianning–Dechang REE belt contained appreciable chloride (Cl−), sulfate (SO 4 2−), and fluoride (F−), and formed an alkali-, sulfate-, and halogen-rich fluid system, in which chloride REE complexes were predominant over sulfate and fluoride complexes in hydrothermal stage I, whereas sulfate species were predominant in hydrothermal stage II. Fluoride was a depositional ligand in hydrothermal stage II, resulting in formation of REE-rich fluorite (CaF 2) and removal of REEs from the fluids. Due to mixing with meteoric water and further cooling, all ligands became involved in the efficient deposition of REEs by destabilization of complexes and widespread precipitation of barite, fluorite, and bastnäsite-(Ce) in the REE mineralization stage. [Display omitted] • Bulk fluid analysis can effectively quantify carbonatitic fluid compositions. • Ore fluids at MD were enriched in alkalis, sulfate, halogens, and REEs (>5 wt%). • Hydrothermal processes are important for REE mobilization and mineralization. • Cl− and SO 4 2− are the major ligands responsible for hydrothermal REE mobilization. • High ligand, alkali, and CO 2 contents facilitate potential REE mineralization. [ABSTRACT FROM AUTHOR]

Abstract: Allele frequencies of the 15 STR loci were determined in 208 unrelated individuals from Han population living in Henan, China (central China). All loci except D5S818 were found no deviation from Hardy–Weinberg equilibrium. The combined power of discrimination (PD) and the combined chance of exclusion (CE) for the 15 studied loci were >0.9999999 and 0.999996119, respectively. Our data were statistically compared with the previously reported data from other Chinese population groups, and significant difference was found between central Han Chinese (n =208) and eastern Chinese (n =100) at vWA, or between central Han Chinese (n =208) and southeast Chinese (n =122) at D13S317. [Copyright &y& Elsevier]

• Public health professionals in China evaluated the roll-out of the hepatitis E vaccine. • Participants provided feedback on different institutions and feasible goals. • Medical doctors and the government had limited knowledge of hepatitis E. • The public sector was a trusted source of information. • Recommendations for promotion of the vaccine in the future are provided. A hepatitis E (HepE) vaccine was developed and released in China in 2011. Uptake is currently very limited. The aims of this study were to characterize what public health professionals thought about promoting the HepE vaccine in Shanghai, China, and to develop realistic goals for the HepE vaccine based on this information. Public health professionals from Shanghai and other jurisdictions of China were contacted to participate in in-depth qualitative interviews between October 2017 and August 2018. Participants were asked about their perception of the HepE vaccine roll-out. Codes were initially based on the structure of the questionnaire. Subsequently, similar ideas were further developed into themes based on what was present in the transcript data. Thirty-five individuals participated. Major topics of discussion included (1) clarifying the roles and responsibilities of private and public institutions in promoting and marketing the HepE vaccine, (2) identifying what methods of promotion were most efficient, and, (3) endeavoring to formulate a reasonable and realistic goal, if any, for HepE prevention and control in China. Participants emphasized that public sector sources can be trusted sources of information (although the private vaccination company can also be useful in disseminating information) and social media such as WeChat can be good ways to disseminate articles (although netizens may be worried about the spread of fake news). Vaccine promotion is restrained given limited levels of knowledge in the government, hospitals, and public health vaccination centers. Successful promotion and use of this vaccine in China, even in limited settings (for instance, certain workplaces, or certain groups) could provide additional information on long-term safety and could promote its adoption in other regions of the world where HepE has high morbidity among pregnant women and other populations. [ABSTRACT FROM AUTHOR]

Identifying the relationships between the yield of rainfed maize and planting densities as well as the hybrids used is crucial for ensuring the sustainable development of the grain industry in high latitude China. In this study, we collected 108 grain yield date points from our multiyear (2017–2020) field experiments and combined 213 data points collected from 21 published papers to appraise the impact of planting density and hybrids on maize yield. It was found that grain yield forms a curvilinear relationship with plant density as it increased from 22,500 to 112,500 plants ha−1. The optimum plant density (OPD) was determined to be 72500 plants ha−1, with a maximum maize grain yield of 10.56 Mg ha−1. The interannual variability in grain yields among hybrids with different planting densities was mainly due to the differences in dry matter (DM), especially post-silking. Grain yields increased significantly with a rise in the proportion of post-silking DM to DM at maturity. In addition, both the collected literature and our field experiments showed that the OPD was positively correlated with solar radiation accumulated during the maize growth period and with each hybrid's year of release. This study suggests that increasing plant density and selecting new hybrids with suitable growth periods are effective approaches for increasing grain yield in high latitude China. [ABSTRACT FROM AUTHOR]

An outbreak of 2019 coronavirus disease (COVID-19) occurred in Wuhan (Hubei, China) in December, 2019. Facing this largescale infectious public health event, everyone is under great psychological pressure. The aim was to investigate the psychological status of people affected by the COVID-19 outbreak in China. The online cross-sectional study involving 922 participants (656 medical staff and 266 general population) was conducted in China between February and March, 2020. The psychological status was evaluated using the Symptom Check List 90 Revised (SCL-90). Linear and logistic regression analysis were used to examine the effect in the study. Of the 922 participants, approximately 18.3% had psychological health problems. The score of the SCL-90 was significant higher in medical staff (mean = 1.49) than that in general population (mean = 1.36). In addition, the participants enrolled in March were less likely to have psychological health problems than in February (odds ratio = 0.42, 95% confidence interval [CI] = 0.30 to 0.59). Female had a 1.44-fold risk of psychological health problems than male (95% CI = 1.01 to 2.03). In the study, 18.3% had psychological health problems during the outbreak of COVID-19 epidemic. With the remission of the epidemic, the psychological health status of participants has been improved. Medical staff were likely to have higher SCL-90 scores than general population and female had more psychological problems than male. Our findings can be used to formulate psychological interventions for improving the mental health of vulnerable groups during the COVID-19 epidemic. • The participant in March have less psychological health problems than in February. • Medical staff were likely to have higher SCL-90 scores than general population. • Female was likely to have more psychological health problems than male. [ABSTRACT FROM AUTHOR]

Background: Multidrug-resistant tuberculosis (MDR-TB) is on the rise in China. This study used a dynamic Markov model to predict the longitudinal trends of MDR-TB in China by 2050 and to assess the effects of alternative control measures. Methods: Eight states of tuberculosis transmission were set up in the Markov model using a hypothetical cohort of 100 000 people. The prevalence of MDR-TB and bacteriologically confirmed drug-susceptible tuberculosis (DS-TB+) were simulated and MDR-TB was stratified into whether the disease was treated with the recommended regimen or not. Results: Without any intervention changes to current conditions, the prevalence of DS-TB+ was projected to decline 67.7% by 2050, decreasing to 20 per 100 000 people, whereas that of MDR-TB was expected to triple to 58/100 000. Furthermore, 86.2% of the MDR-TB cases would be left untreated by the year of 2050. In the case where MDR-TB detection rate reaches 50% or 70% at 5% per year, the decline in prevalence of MDR-TB would be 25.9 and 36.2% respectively. In the case where treatment coverage was improved to 70% or 100% at 5% per year, MDR-TB prevalence in 2050 would decrease by 13.8 and 24.1%, respectively. If both detection rate and treatment coverage reach 70%, the prevalence of MDR-TB by 2050 would be reduced to 28/100 000 by a 51.7% reduction. Conclusions: MDR-TB, especially untreated MDR-TB, would rise rapidly under China's current MDR-TB control strategies. Interventions designed to promote effective detection and treatment of MDR-TB are imperative in the fights against MDR-TB epidemics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zircon U-Pb dating indicates that the Yunxian-Jinggu volcanic rocks were formed between 245 and 230 Ma. • Wenyu arc basalts originated from mantle metasomatized by fluids released from the subducted Paleo-Tethys slab. • Magmas of the Yunxian-Jinggu volcanic arc are less conducive to porphyry copper mineralization. Porphyry copper deposits are commonly associated with porphyries generated in arc environments. Assessing the contemporaneous arc volcanic rocks provides crucial insights into the potential for porphyry copper mineralization. The Triassic Yidun arc in the northern part of the Sanjiang orogen in southwest China, which formed in association with the subduction of the Paleo-Tethys Oceanic slab, hosts several porphyry copper deposits. However, the potential for porphyry copper mineralization in the Yunxian-Jinggu volcanic arc in the southern part of the Sanjiang orogen, which was also linked to the subduction of the Paleo-Tethys Oceanic slab, remains unclear. This study reports zircon U–Pb ages, trace element compositions and Hf isotopes, and whole-rock element compositions and Sr–Nd–Pb isotopes of the basaltic-andesitic-dacitic rocks in the Yunxian-Jinggu volcanic arc. Zircon SHRIMP U–Pb dating of the Wenyu basalts and andesites yielded ages of 244.3 ± 1.9 Ma and 242.5 ± 2.5 Ma, respectively. The basalts have arc geochemical affinities with ε Hf (t) values of 2.3 to 9.3, ε Nd (t) values of –0.6 to 0.2, and (87Sr/86Sr) i values of 0.7065 to 0.7068. They have high Ba concentrations (∼ 550 ppm), highly variable Ba/La ratios (0.01 to 0.10), and a narrow range of Th/Yb ratios (1.2 to 1.9). These characteristics suggest that the basalts were derived from mantle metasomatized by fluids likely released from the subducted Paleo-Tethys slab. The Wenyu andesites, with ε Hf (t) values range from 1.6 to 7.0, ε Nd (t) value of –0.4, and (87Sr/86Sr) i value of 0.7031, along with distinct Pb isotopes, were probably produced through basaltic magmas undergoing crustal fractional crystallization. The Minle dacites, sharing similar ε Hf (t) value (–1.6 to 10.7) but lower ε Nd (t) values (–3.1 to –4.9) compared to Wenyu volcanics, are interpreted as derived from partial melting of basaltic magmas with contamination from ancient crustal components. The zircon Eu/Eu* ratios (mostly < 0.4), zircon ΔFMQ value (–0.6 ± 1.1), and bulk-rock Sr/Y ratios (< 10.3) for the Yunxian-Jinggu volcanic rocks indicate that co-genetic intrusions, if present, would likely be less hydrous and less oxidized, making them less favorable for porphyry copper mineralization. [ABSTRACT FROM AUTHOR]

• The ESs exhibited obvious spatial heterogeneity with an increasing temporal trend. • The trade-off or synergistic relationships amongst ESs were significant. • In the optimization scenario of 'increase in NPP but not decrease in WY', ESs increased. • Proper allocation of land use can further optimise ESs. The water resources in the arid regions of Northwest China are scarce, and the ecological environment is fragile. Therefore, the evaluation and optimisation of ecosystem services (ESs) in these regions are key to regional ecological security and sustainable development. Few previous studies have incorporated trade-offs and synergies between services provided by various ecosystems into optimal scenario setting constraints. Here, considering the Shule River Basin (SRB) as a typical arid area, we evaluated four ESs, including net primary productivity (NPP), soil conservation (SC), sand retention (SR), and water yield (WY), from 2001 to 2018, and explored their spatiotemporal characteristics. Combining the synergy of ESs and ecological environment protection objectives of the basin, we designed three optimisation scenarios, namely 'maximum probability of land use suitability' (S1), 'increase in NPP without decrease in WY' (S2), and 'increase in NPP without decrease in SC and SR' (S3), based on the cellular automata model to optimise ESs. The four ESs in the SRB showed fluctuating but increasing temporal trends, with the increase in NPP being the most obvious. Moreover, the four ESs exhibited obvious spatial heterogeneity. WY showed synergistic relationships with the other three services, and these relationships became stronger over time. In S1, SC increased, whilst NPP, SR, and WY decreased; in S2, the four ESs increased; and in S3, NPP, SC, and SR increased, whilst WY decreased slightly. Based on the trade-off and synergy of optimised ESs, the scenarios (S2 and S3) in which the services in synergy with NPP do not decrease can improve the ESs as well as weaken the trade-off and strengthen the synergy between them. These findings are used for stakeholders to deepen their understanding of the future consequences associated with today's human activities and decisions, against a range of possible outcomes. [ABSTRACT FROM AUTHOR]

[Display omitted] • δ34S change is related to f O 2 decrease and sediment addition. • There are two S-Fe sources, one is alkaline magma, the other is 56Fe or 32S-rich sediment. Carbonatite-related rare earth element (REE) deposits are the most significant source of REEs worldwide. The processes of REE precipitation, enrichment, and mineralization remain controversial. The Cenozoic Mianning–Dechang (MD) REE belt, located in Sichuan Province, southwestern China, comprises one giant (Maoniuping), one large (Dalucao), and two small–medium (Muluozhai and Lizhuang) deposits. These deposits provide a continuous record of fluid evolution, and thus are ideal for investigating the processes of REE mineralization in carbonatite-related REE deposits. Given that sulfate (i.e., barite and celestite) and sulfide (i.e., pyrite and galena) minerals crystallized and precipitated in the pegmatitic to hydrothermal stages, respectively, the REE minerals formed later than the sulfate minerals. However, the formation sequence of the sulfide minerals and bastnäsite is unclear, although both pyrite and bastnäsite formed in the late hydrothermal stage. We used S isotope data for sulfate and sulfide minerals and Fe isotope data for pyrite to investigate the composition and evolution of ore-forming fluids during the magmatic–hydrothermal stages. The sulfate minerals have positive δ34S CDT values (+3.2‰ to +8.3‰), and the sulfide minerals have negative δ34S CDT values (−13.5‰ to − 5.6‰) in the four REE deposits. In the Maoniuping deposit, δ34S CDT values for barite from the pegmatitic stage (+4.7‰ to +5.7‰) are higher than for barite from the hydrothermal stage (+4.1‰ to +4.5‰), which indicate that hydrothermal activity led to relative enrichment in isotopically light S. The δ34S CDT values for barite (+3.2‰ to +5.5‰) are lower than for celestite (+6.2‰ to +7.2‰) from the pegmatitic stage in the Dalucao deposit. The δ34S CDT values for galena (−13.5‰) are also lower than for pyrite (−13.5‰ to −7.2‰) from the hydrothermal stage in the Guangtoushan section. In general, δ34S CDT values change from positive to negative values (+8.3‰ to −16.4‰) as the fluids evolved from the pegmatitic to hydrothermal stages, which can be attributed to a decrease in oxygen fugacity (f O 2) and addition of sediment containing isotopically light S. Iron isotopic compositions of pyrite from the hydrothermal stage show significant variations (δ56Fe IRMM-014 = −0.03‰ to +0.65‰ for the Maoniuping deposit; −0.14‰ to 0.00‰ for the Dalucao deposit; +0.05‰ to +0.35‰ for the Lizhuang deposit), and are higher than those for the carbonatites (δ56Fe IRMM-014 = −0.47‰ to −0.17‰). These data indicate there are two sources of Fe in the MD REE belt, which are the carbonatite–nordmarkite magma and 56Fe-rich sediment. Paleozoic–Mesozoic volcanic–sedimentary and Mesozoic clastic and carbonate rocks are exposed in the MD REE belt. In general, the S–Fe isotope data, along with geological and petrographic observations, indicate that the REE minerals formed later than the sulfate minerals, and the S–Fe were derived from both carbonatite magma and sediment containing isotopically light S and heavy Fe. [ABSTRACT FROM AUTHOR]

Erect panicle (EP) is one of the more important traits of the proposed ideotype of high-yielding rice. Several rice cultivars with the EP phenotype, which has been reported to be controlled by a dominant gene, have been successfully developed and released for commercial production in North China. To analyze the inheritance of the EP trait, we generated segregating F2 and BC1F1 populations by crossing an EP-type variety, Liaojing 5, and a curved-panicle-type variety, Fengjin. Our results confirmed that a dominant gene controls the EP trait. Simple-sequence repeat (SSR) and bulked segregant analyses of the F2 population revealed that the EP gene is located on chromosome 9, between two newly developed SSR markers, RM5833-11 and RM5686-23, at a genetic distance of 1.5 and 0.9 cM, respectively. Markers closer to the EP gene were developed by amplified fragment length polymorphism (AFLP) analysis with 128 AFLP primer combinations. Three AFLP markers were found to be linked to the EP gene, and the nearest marker, E-TA/M-CTC200, was mapped to the same location as SSR marker RM5686-23, 1.5 cM from the EP gene. A local map around the EP gene comprising nine SSR and one AFLP marker was constructed. These markers will be useful for marker-assisted selection (MAS) for the EP trait in rice breeding programs. [ABSTRACT FROM AUTHOR]

The article reports on the study which investigates the chemical constituents and antimicrobial activities of essential oil extracts from Pteris multifida taken from Pingjiang in Hunan, China. Agar-well diffusion method for the methanol extracts and agar-disc diffusion method for the essential oils (EO) have been employed for the determination of antimicrobial activities. It also determined the inhibitory concentration and minimum bactericidal concentration of EO against the test microorganisms.

The article presents a study which investigates on the chemical constituents of the aerial parts of Vetiveria zizanioides specie which is commonly known as vetiver grass. The study was conducted to the specie collected in Zhejiang Province, China in August 2009, wherein the air-dried powdered plant material was extracted from the specie. The study used several analysis techniques such as gel column chromatography and nuclear magnetic resonance (NMR).

The article discusses the impact of the headwater loss of the western plateau to the increasing water-shortage problems in China. Several factors were cited that contribute to the water shortage of the country which include the rapid population and economic growth, and the loss of glaciers and wetlands in the western plateau that feed the major rivers of China. To overcome the water supply challenges, several scientific and technological problems in the country should be solved such as the efficient water use in cropland and industry, saving water storage, and equal allocation of water.