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In a rice (Oryza sativa L.)–wheat (Triticum aestivum L.) rotation system, a study was conducted to determine the effects of different fertilization regimens (no fertilization, replacement of a portion of chemical fertilizer with composted pig manure, chemical fertilizer only, and straw return combined with chemical fertilizer) on the weed communities and wheat yields after 4 and 5 yr. The impact of the long-term recurrent fertilization regimen initiated in 2010 on the composition and diversity of weed communities and the impact of the components and total amount of fertilizer on wheat yields were assessed in 2014 and 2015. Totals of 19 and 16 weed species were identified in experimental wheat fields in 2014 and 2015, respectively, but the occurrence of weed species varied according to the fertilization regimen. American sloughgrass [Beckmannia syzigachne (Steud.) Fernald], water starwort [Myosoton aquaticum (L.) Moench], and lyrate hemistepta (Hemistepta lyrata Bunge.) were adapted to all fertilization treatments and were the dominant weed species in the experimental wheat fields. The greatest number of weed species were observed under the no-fertilization treatment, in which 40% of the weed community was composed of broadleaf weeds and the lowest wheat yields were obtained. With fertilizer application, the number of weed species was reduced, the height of weeds increased significantly, the density of broadleaf weeds was significantly reduced, the biodiversity indices of weed communities decreased significantly, and higher wheat yields were obtained. Only the chemical fertilizer plus composted pig manure treatment and the chemical fertilizer–only treatment increased the density of grassy weeds and the total weed community density. The treatment with chemical fertilizer only also resulted in the highest density of B. syzigachne. Rice straw return combined with chemical fertilizer yielded the lowest total weed density, which suggests that it inhibited occurrence of weeds. The different fertilizer regimens not only affected the weed species composition, distribution, and diversity, but also the weed density. Our study provides new information from a rice–wheat rotation system on the relationship between soil amendments and agricultural weed infestation.
Population-based colorectal cancer (CRC) screening programs that use a fecal immunochemical test (FIT) are often faced with a noncompliance issue and its subsequent waiting time (WT) for those FIT positives complying with confirmatory diagnosis. We aimed to identify factors associated with both of the correlated problems in the same model.
A total of 294,469 subjects, either with positive FIT test results or having a family history, collected from 2004 to 2013 were enrolled for analysis. We applied a hurdle Poisson regression model to accommodate the hurdle of compliance and also its related WT for undergoing colonoscopy while assessing factors responsible for the mixture of the two outcomes.
The effect on compliance and WT varied with contextual factors, such as geographic areas, type of screening units, and level of urbanization. The hurdle score, representing the risk score in association with noncompliance, and the WT score, reflecting the rate of taking colonoscopy, were used to classify subjects into each of three groups representing the degree of compliance and the level of health awareness.
Our model was not only successfully applied to evaluating factors associated with the compliance and the WT distribution, but also developed into a useful assessment model for stratifying the risk and predicting whether and when screenees comply with the procedure of receiving confirmatory diagnosis given contextual factors and individual characteristics.
Hepatitis B constitutes a severe public health challenge in China. The Community-based Collaborative Innovation hepatitis B (CCI-HBV) project is a national epidemiological study of hepatitis B and has been conducting a comprehensive intervention in southern Zhejiang since 2009.
The comprehensive intervention in CCI-HBV areas includes the dynamic hepatitis B screening in local residents, the normalised treatment for hepatitis B infections and the upcoming full-aged hepatitis B vaccination. After two rounds of screening (each round taking for 4 years), the initial epidemiological baseline of hepatitis B in Qinggang was obtained, a coastal community in east China. By combining key data and system dynamics modelling, the regional hepatitis B epidemic in 20 years was predicted.
There were 1041 HBsAg positive cases out of 12 228 people in Round 1 indicating HBV prevalence of 8.5%. Of the 13 146 people tested in Round 2, 1171 people were HBsAg positive, with a prevalence of 8.9%. By comparing the two rounds of screening, the HBV incidence rate of 0.192 per 100 person-years was observed. By consulting electronic medical records, the HBV onset rate of 0.533 per 100 person-years was obtained. We generated a simulated model to replicate the real-world situation for the next two decades. To evaluate the effect of interventions on regional HBV prevalence, three comparative experiments were conducted.
In this study, the regional hepatitis B epidemic in 20 years was predicted and compared with HBV prevalence under different interventions. Owing to the existing challenges in research methodology, this study combined HBV field research and simulation to provide a system dynamics model with close-to-real key data to improve prediction accuracy. The simulation also provided a prompt guidance for the field implementation.
Information on the genetic population structure of economic species is important for understanding their evolutionary processes and for management programmes. In this study, the genetic structure of 12 P. trituberculatus populations along the China seas and Japan was analysed. A fragment of mitochondrial control region was sequenced as a genetic marker in swimming crabs sampled from the Bohai Sea, Yellow Sea, East China Sea, South China Sea and Japan, with dense sampling in the Bohai Sea. These populations showed an intermediate and significant genetic population structure, with an overall Φst value of 0.054 (P < 0.01). Based on a hierarchical AMOVA, they could be divided into two groups, the South China Sea population and all the other populations. The distribution of the haplotypes and the pairwise Φst values between populations indicated a high level of gene flow among most populations in the Bohai Sea, Yellow Sea, East China Sea and Japan. However, low but significant genetic differentiation (P < 0.05) was also detected among several populations in these areas. Many details of the genetic structure were revealed, especially for the populations in the semi-enclosed Bohai Sea, and the inconsistency with previous studies was discussed. The structure patterns indicate that sea-level changes during the glacial period of the Pleistocene and oceanographic factors are important in shaping the genetic population structure of swimming crabs. Finally, the implications for fishery are suggested.
Previous neuroimaging studies demonstrated that retinal detachment (RD) subjects were associated with abnormal spontaneous brain activities; however, whether the altered interhemispheric functional connectivity (FC) occurred in RD patients remains unknown. The current study tried to explore the alternations of interhemispheric FC of the whole brain in unilateral RD patients using the voxel-mirrored homotopic connectivity (VMHC) method and their connections to clinical features. Methods: We recruited 30 patients with RD (16 males and 14 females) and 30 healthy controls (HCs) (16 males and 14 females) whose age and sex were closely matched. All subjects underwent the rs-fMRI scans. The VMHC method was applied to directly assess the hemispheres’ functional interaction. The VMHC in these brain areas, which could be used as biomarkers to differentiate RD from HC, was identified by the receiver operating characteristic (ROC) curve analyses. The relations between these patients’ clinical features and their mean VMHC signal values in multiple brain regions were calculated by Pearson correlation analysis. Results: RD patients had significantly lower VMHC values than HCs in the bilateral occipital lobe (Brodmann areas, BA 18), bilateral superior temporal gyrus (BA 39), and bilateral cuneus (BA 19). Moreover, the mean VMHC signal values of the bilateral cuneus were in positive correlation with the duration of the RD (r = 0.446, P = 0.013). Conclusion: Our results provided an evidence of disturbed interhemispheric FC in the visual area occurred in RD patients, which might provide some useful information to understand the neural mechanism of RD patients with acute vision loss. Furthermore, the VMHC values might indicate the progress of the RD.
Suicide attempt (SA), which is one of the strongest predictors of completed suicide, is common in major depressive disorder (MDD) but its prevalence across epidemiological studies has been mixed. The aim of this comprehensive meta-analysis was to examine the pooled prevalence of SA in individuals with MDD.
A systematic literature search was conducted in PubMed, Embase, PsycINFO, Web of Science and Cochrane Library from their commencement date until 27 December 2017. Original studies containing data on prevalence of SA in individuals with MDD were analyzed.
In all, 65 studies with a total of 27 340 individuals with MDD were included. Using the random effects model, the pooled lifetime prevalence of SA was 31% [95% confidence interval (CI) 27–34%], 1-year prevalence was 8% (95% CI 3–14%) and 1-month prevalence was 24% (95% CI 15–34%). Subgroup analyses revealed that the lifetime prevalence of SA was significantly associated with the patient setting, study region and income level, while the 1-month prevalence of SA was associated with only the patient setting.
This meta-analysis confirmed that SA was common in individuals with MDD across the world. Careful screening and appropriate interventions should be implemented for SA in the MDD population.
Several previous prospective studies suggest that consumption of green leafy and cruciferous vegetables may lower the risk of type 2 diabetes (T2D). We investigated the association between consumption of different types of vegetables in relation to T2D risk in an Asian Population. We included 45 411 participants (age range: 45–74 years) of the Singapore Chinese Health Study (SCHS) free of diabetes, cancer or CVD at baseline (1993–1998). Dietary information was collected using a validated FFQ. Physician-diagnosed incident diabetes was reported at follow-up I (1999–2004) and II (2006–2010) interviews. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI of T2D risk. An updated meta-analysis was also conducted to summarise results for green leafy and cruciferous vegetables. During 494 741 person-years of follow-up, 5207 incident T2D occurred. After adjustment for potential confounders, neither total vegetables (top v. bottom quintile HR=1·08; 95 % CI 0·98, 1·18, Ptrend=0·66) nor specific vegetables including dark green leafy vegetables (HR=1·05; 95 % CI 0·96, 1·15, Ptrend=0·21) and cruciferous vegetables (HR=0·97; 95 % CI 0·88, 1·06, Ptrend=0·29) were substantially associated with risk of T2D. A meta-analysis (eleven studies with 754 729 participants and 58 297 cases) including the SCHS and all previous prospective studies suggested borderline significant inverse associations between green leafy (summary relative risk (RR)=0·91; 95 % CI 0·84, 1·00) and cruciferous vegetable consumption (RR=0·87; 95 % CI 0·76, 1·00) and T2D risk, with moderate-to-high heterogeneity. In conclusion, green leafy or cruciferous vegetable consumption was not substantially associated with risk of T2D in an Asian population. Meta-analysis of available cohort data indicated that evidence for a beneficial effect of green leafy or cruciferous vegetable consumption on T2D risk is not convincing.
In the above publication by Chen et al. (2017), the authors neglected to include that Dr. Zhang was supported by the 111 Project (Grant Number B16031) as part of their financial support and conflicts of interest. The complete corrected conflicts of interest section is provided below:
The authors report grants from the National Natural Science Foundation of China, grants from the National Science & Technology Pillar Program during the Twelfth Five-year Plan Period, and grants from the Key Discipline in Shanghai during the conduct of the study. Dr. Zhang was supported by the 111 Project (Grant Number B16031).
Objectives: The aim of this study was to evaluate the universal newborn hearing screening (UNHS) and intervention program in Shanghai, China.
Methods: This study included the quantitative analyses of the UNHS-Shanghai database in 2002–12 and qualitative assessment of the program. The Otoacoustic Emissions and the Automated Auditory Brainstem Evoked Responses tests were conducted in screening. The costs and benefits were calculated based on the number of participants in each stage. The short-term and long-term periods were defined as from birth to 15 years of age or to death (82-year-olds), respectively. Sensitivity analyses were conducted.
Results: A total 1,574,380 newborns were included, representing 93.6 percent of all eligible babies in Shanghai during the study period. The prevalence of newborn hearing loss was 1.66‰. The short-term/long-term program costs were ¥488.5 million (US$75.52 million)/¥1.08 billion (US$167.12 million), and the short-term/long-term program benefit was ¥980.1 million (US$151.53 million)/¥8.13 billion (US$1.26 billion). The program benefit was greater than its cost if the proportion of hearing-loss children enrolled in regular schools was no less than 41.4 percent of all hearing impaired children, as well as if the wage growth rate ranged from 3 percent to 8 percent. Qualitative results also suggested that stakeholders strongly supported this program.
Conclusions: The universal newborn hearing screening and intervention program in Shanghai is justified in terms of the resource input in the long run, although there is still room for further improvement with respect to educational rehabilitation and a better infrastructure system.
Background: Good primary health care can enhance national health status at relatively low cost. The barefoot doctor model in China was once considered to have been a successful health care policy. It was a model which was followed by other low-developed or developing countries. In recent decades, the Chinese government promulgated a number of new policies and health reforms to improve its health care system. Aim: This paper aimed to highlight the great significance of primary health care and appeal to the policymakers to change the priority to primary health care in order to be able to guarantee universal health care for the whole nation at least at primary care level. Method: This study discussed Chinese primary health care by reviewing its history and development. Finding: Chinese government’s efforts do not seem to be leading to a completely successful outcome for all the people of China as a result of the substantial imbalance of investments between tertiary level hospitals and grass-root level health care institutions. The government appears to have neglected the importance of primary health care in the implementation of health systems and resources.
Elemental mapping at the atomic-scale by scanning transmission electron microscopy (STEM) using energy-dispersive X-ray spectroscopy (EDS) provides a powerful real-space approach to chemical characterization of crystal structures. However, applications of this powerful technique have been limited by inefficient X-ray emission and collection, which require long acquisition times. Recently, using a lattice-vector translation method, we have shown that rapid atomic-scale elemental mapping using STEM-EDS can be achieved. This method provides atomic-scale elemental maps averaged over crystal areas of ~few 10 nm2 with the acquisition time of ~2 s or less. Here we report the details of this method, and, in particular, investigate the experimental conditions necessary for achieving it. It shows, that in addition to usual conditions required for atomic-scale imaging, a thin specimen is essential for the technique to be successful. Phenomenological modeling shows that the localization of X-ray signals to atomic columns is a key reason. The effect of specimen thickness on the signal delocalization is studied by multislice image simulations. The results show that the X-ray localization can be achieved by choosing a thin specimen, and the thickness of less than about 22 nm is preferred for SrTiO3 in  projection for 200 keV electrons.
The high-cycle fatigue (HCF) behavior is significantly affected by surface roughness, especially for high strength metal FV520B-I. However, with surface roughness effect, neither the fatigue property, nor the high-cycle fatigue life model about FV520B-I with surface roughness has been reported. In this paper, designed fatigue experiment using the specimen with different surface roughness is presented to study the effectiveness of the roughness to the fatigue. The observations of the fatigue crack initiation sites and the crack propagation. Then the high cycle fatigue behavior of FV520B-I affected by surface roughness is analyzed. The existing very-high-cycle fatigue life model is not well-fit for high-cycle fatigue model of FV520B-I. A NEW high-cycle fatigue life prediction model of FV520B-I, taking surface roughness as a main effective variable is proposed. The model is built up by a comprehensive use of experimental data and the traditional fatigue modeling theory. The new finding between the fatigue strength coefficient and stress amplitude, with surface roughness, is adopted, leading to a NEW modified life prediction model. Study on fatigue model of FV520B-I with surface roughness is a very beneficial effort in fatigue theory and fatigue engineering development.
In late 2010, the online services giant Google released a tool for public use called the Google Books Ngram Viewer. The Ngram viewer was a Web interface that enabled virtually anyone with an Internet connection to run frequency searches of character strings in a corpus of more than 5.2 million digitized books, or roughly 500 billion words, published between the sixteenth and twenty-first centuries. With these massive corpora at hand, a new branch of humanistic research has been established, dubbed “culturomics” (Michel et al., 2011). Culturomics enables investigators to examine changes over time reflected in print material associated with the lexicon being used and can offer evidence of social patterns and orientations within a language community. For example, one could use the Ngram viewer to chart how often the word “slavery” was printed over time and see that it increased dramatically in the years leading up to the US Civil War and had since declined substantially. Similarly, one could look at the appearance of technological innovations, such as the radio and the telephone, in print material and infer that the rate of cultural adoption of these technologies has increased over time. These kinds of capabilities are not contingent on the existence of the Ngram Viewer, but rather reflective of how analysts can look toward word usage in print materials from different times to understand changes within a community and culture (e.g., Lieberman et al., 2007).
What would such an approach tell us about the learning sciences (LS)? Granted, the field spans decades rather than centuries, and the corpus of associated text is modest even against the wide range of education research literature published during the same period of time. However, it is our suspicion that even for a field that is still emerging and establishing its academic identity, an examination of frequency of word use across different times could be informative for our understanding of the field. This chapter summarizes some of our efforts to do that work. Building upon an analysis presented in 2012 (Lee, Ye, & Recker, 2012), we provide here an elaborated comparative analysis of proceedings from the first and the most recent (at the time of this writing) LS conferences (Birnbaum, 1991; Polman et al., 2014), as well as a third conference, roughly collocated with the first LS conference (Gomez, Lyons, & Radinsky, 2010).
The strain hardening effect and dynamic recovery behavior of a Ni-based superalloy are studied by isothermal compressive tests. A new unified dislocation-density based constitutive model is developed to characterize the strain hardening effect and dynamic recovery behavior of the studied superalloy. In the developed constitutive model, some material parameters (yield stress, strain hardening coefficient, and dynamic recovery coefficient) are assumed as functions of initial grain size, deformation temperature, and strain rate. An iterative algorithm is designed to predict the high-temperature deformation behaviors under time-variant hot working conditions. The hot deformation parameters and material parameters can be updated in each strain increment. Comparisons between the experimental and calculated flow stresses indicate that the developed constitutive model can accurately describe the high-temperature deformation behavior of the studied superalloy. Furthermore, the developed constitutive model is also successfully used for analyzing time-variant hot working processes.