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In coastal saline rice fields, rice production shows high greenhouse gas (GHG) emissions but low nitrogen use efficiency (NUE). However, few studies have focused on the combined effects of nitrogen (N) fertilizer and soil ameliorants on GHG emissions. Thus, a field experiment was conducted to study the combined effects of N fertilizer, humic acid, and gypsum on the global warming potential (GWP), yield-scaled greenhouse gas intensity (GHGI), rice grain yield, and NUE in coastal saline rice fields in southeastern China. The experiment was conducted with eight treatments: N0, N1, N0H1, N1H1, N0G1, N1G1, N0H1G1, and N1H1G1. The codes N0, N1, H1, and G1 represented treatments without N (0 kg N ha-1), with N (300 kg N ha-1), with humic acid (0.6 t ha-1), and with gypsum (0.6 t ha-1), respectively. Compared with the treatments without N addition, the application of N fertilizer significantly increased N2O emissions and grain yield by 41.9~130.6% and 32.8~57.5%, respectively, while significantly decreased the yield-scaled GHGI by 9.4~31.9%. Humic acid amendment significantly increased N2O emissions and grain yield as compared with the treatments without humic acid. Gypsum addition had no significant effects on CH4 and N2O emissions, GWP, yield-scaled GHGI, and grain yield in relation to the treatments without gypsum. In addition, compared with the N1 treatment, the N1H1, N1G1, and N1H1G1 treatments increased the grain yield by 18.3% (p < 0.05), 2.3%, and 10.4%, and decreased yield-scaled GHGI by 9.6%, 20.5%, and 31.2% (p < 0.05), despite similar GWPs, respectively. Overall, the N1H1 and N1H1G1 treatments are the appropriate fertilizer management to realize high yield together with low environmental impacts in coastal saline rice fields in China.

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Hog pseudorabies (Aujeszky's disease) can incur serious losses for farm owners and even the entire hog industry by causing infertility, abortion, and stillbirth among sows, as well as diarrhoea, respiratory failure, and death among piglets. Pseudorabies virus could be prevented, controlled, and eliminated by clean-up at both farm and regional levels through a strict procedure of vaccination, quarantine, diagnosis, elimination of positive animals, and healthy animals nurturing. Using data from 63 large-scale hog farms from nine provinces (municipalities, autonomous regions) of China, we evaluated the economic consequences of hog pseudorabies clean-up in China's hog farms based on a partial budgeting method. By comparing large-scale hog farms that have performed pseudorabies clean-up with similar farms that have not, we analysed how clean-up affected farm profit and whether there existed sufficient economic incentives for farm owners to adopt pseudorabies control measures. Further, we examined how the economic consequences varied with factors such as clean-up history and farm size. The findings showed that, on average, clean-up adopters outperformed non-adopters by 8.02 million yuan per farm per year within the four years post clean-up adoption. Also, we found that the net profit changes attributable to pseudorabies clean-up increased over time and with farm size. Although we cannot extrapolate to all Chinese hog farms, these findings suggest that the earlier a hog farm adopted pseudorabies clean-up, the larger the economic benefits would be, especially for large-scale farms.

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BACKGROUND: Recently, a wide variety of studies have suggested that elevated platelet counts are associated with survival in patients with colorectal cancer. On one hand several studies suggest a negative connection in colorectal cancer patients with pre-operative thrombocytosis, on the other hand other studies contradicts this. However, it remains unknown whether elevated platelet counts are associated with survival in colorectal cancer patients. We therefore conducted this meta-analysis to evaluate the prognostic role of platelet counts in colorectal cancer. METHODS: PubMed, Embase, and the Cochrane Library databases were searched from their inception to October 15, 2016 to identify relevant studies that have explored the prognostic role of platelet counts in colorectal cancer. Studies that examined the association between platelet counts and prognoses in colorectal cancer and that provided a hazard ratio (HR) and 95% confidence interval (CI) for overall survival (OS) and/or disease-free survival (DFS) were included. RESULTS: This meta-analysis included 9 retrospective cohort studies involving 3413 patients with colorectal cancer. OS was shorter in patients with elevated platelet counts than in patients with normal counts (HR 2.11, 95% CI: 1.68-2.65). For DFS, an elevated platelet count was also a poor predictor (HR 2.51, 95% CI: 1.84-3.43). CONCLUSION: In this meta-analysis, we suggest that an elevated platelet count is a negative predictor of survival in both primary colorectal cancer and resectable colorectal liver metastases.

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Research-enabled growth in agricultural productivity is pivotal to sub-Saharan Africa's overall economic growth prospects. Yet, investments in research and development (R&D) targeted to many national food and agricultural economies throughout Africa are fragile and faltering. To gain insight into what could be driving this trend, this article updates, summarizes and reassesses the published evidence on the returns to African agricultural R&D. Based on a compilation of 113 studies published between 1975 and 2014 spanning 25 countries, the reported internal rates of return (IRRs) to food and agricultural research conducted in or of direct consequence for sub-Saharan Africa averaged 42.3%py. In addition to the 376 IRR estimates, the corresponding 129 benefit-cost ratios (BCRs) averaged 30.1. Most (96.5%) of the returns-to-research evaluations are of publicly performed R&D, and the majority (87.6%) of the studies were published in the period 1990-2009. The large dispersion in the reported IRRs and BCRs makes it difficult to discern meaningful patterns in the evidence. Moreover, the distribution of IRRs is heavily (positively) skewed, such that the median value (35.0%py) is well below the mean, like it is for research done elsewhere in the world (mean 62.4%py; median 38.0%py). Around 78.5% of the evaluations relate to the commodity-specific consequences of agricultural research, while 5.5% report on the returns to an "all agriculture" aggregate. The weight of commodity-specific evaluation evidence is not especially congruent with the composition of agricultural production throughout Africa, nor, to the best that can be determined, the commodity orientation of public African agricultural R&D.

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PURPOSE: Numerous studies have investigated the associations between methylenetetrahydrofolate reductase (MTHFR) gene C677T and A1298C polymorphisms and risk of recurrent pregnancy loss (RPL); however, the results remain controversial. The aim of this study is to drive a more precise estimation of association between MTHFR gene polymorphisms and risk of RPL. METHODS: We searched PubMed, EMBASE, Cochrane library, Web of Science and China Knowledge Resource Integrated Database for papers on MTHFR gene C677T and A1298C polymorphisms and RPL risk. The pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the strength of association in the homozygous model, heterozygous model, dominant model, recessive model and an additive model. The software STATA (Version 13.0) was used for statistical analysis. RESULTS: Overall, 57 articles were included in the final meta-analysis. In maternal group the MTHFR C677T polymorphism showed pooled odds ratios for the homozygous comparison [OR = 2.285, 95 % CI (1.702, 3.067)] and the MTHFR A1298C polymorphism showed pooled odds ratios for recessive model [OR = 1.594, 95 % CI (1.136, 2.238)]. In fetal group the MTHFR C677T polymorphism showed pooled odds ratios for dominant model [OR = 1.037, 95 % CI (0.567, 1.894)] and the MTHFR A1298C polymorphism showed pooled odds ratios for dominant model [OR = 1.495, 95 % CI (1.102, 2.026)]. CONCLUSIONS: In summary, the results of our meta-analysis indicate that maternal and paternal MTHFR gene C677T and A1298C polymorphisms are associated with RPL. We also observed a significant association between fetal MTHFR A1298C polymorphism and RPL but not C677T.

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