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In conservation tillage systems, proper fertilizer phosphorus (P) and potassium (K) management is critical to optimize yield and minimize negative environmental impacts. The objective of this study was to assess the responses of crop yield, nutrient use efficiencies, root growth, and soil test P and K levels to tillage, fertilizer placement, and fertilizer rates in a corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation. Experiments were conducted for 8 yr in Illinois with tillage/fertilizer placement as the main plot (no‐till/broadcast [NTBC], strip‐till/broadcast [STBC], and strip‐till/deep band [STDB]) and PK fertilizer rates as the subplot. The NTBC treatment consistently reduced yields in corn by 6.2 and 4.5% and in soybean by 3.1 and 6.1% relative to STBC and STDB, respectively. Also, NTBC had greater root length density at in‐row and between‐row positions relative to STBC and STDB. Nutrient use efficiency indices (partial nutrient balance, agronomic efficiency, and partial factor productivity) declined with increasing P and K rates but were not affected by tillage/fertilizer placement treatments. Deep banding significantly reduced soil P and K concentrations in surface layers while increasing them at the depth of application. These results underscore the reported potential for deep banding combined with strip‐till to improve conditions for nutrient uptake while reducing the risk for nutrient losses to the environment. Critical soil test P and K levels (21 mg P kg−1 and 217 mg K kg−1) were similar for P and greater for K than the current university recommendations, which highlights the need for continuous refinement of soil fertility recommendations to keep pace with changes in production technologies and yield levels. [ABSTRACT FROM AUTHOR]

The environmental consequences of residue removal practices to support cellulosic biofuel production remain poorly understood. In the U.S. Midwest, corn (Zea mays L.) stover removal combined with no‐till practices may increase or decrease soil N2O emissions by influencing soil moisture, temperature, and nutrient dynamics, yet empirical evidence from long‐term field experiments is inconsistent. We investigated the effects of residue management (residue retained or removed) and tillage (chisel‐till or no‐till) on cumulative soil nitrous oxide (N2O) emissions, grain yield, and yield‐scaled N2O emissions in a 3‐year study initiated 10 years after treatment implementation in a long‐term, continuous corn experiment in Illinois, United States. Crop yields were affected by treatment in only one of three study years, with the combination of residue removal and no‐till reducing yields compared to both chisel‐till treatments. Cumulative N2O emissions, soil inorganic N concentrations, and yield‐scaled N2O emissions differed over the 3‐year period and were significantly affected by tillage, with no response to residue management. In 2 years, no‐till decreased cumulative N2O emissions and yield‐scaled N2O emissions by an average of 64% and 60%, respectively. Correlations between daily N2O fluxes and soil moisture, temperature, and inorganic N concentrations suggested that the relative importance of these variables changed depending on year and treatment. While more research across a range of sites and management practices is needed, our findings support previous studies which have challenged IPCC methodology assumptions regarding the effects of residue removal on N2O emissions. We conclude there is inherent difficulty in predicting the impacts of residue removal due to the complexity of soil processes underlying N2O emissions coupled with inter‐annual weather variability in this rainfed continuous corn system. Future efforts to evaluate the net greenhouse gas emissions of cellulosic biofuel production may benefit from accounting for this uncertainty. When evaluating net GHG emissions of removing corn stover to support cellulosic biofuel, life cycle assessment and IPCC approaches commonly predict soil nitrous oxide emissions will decrease. Our results support a growing evidence‐base showing nitrous oxide emissions do not necessarily decrease, implying the benefits of biofuels may be overestimated. [ABSTRACT FROM AUTHOR]

Abstract: We conducted this meta‐analysis to explore the prognostic value of outpatient (or office) hysteroscopy (OH) preceding in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles in women who had experienced repeated implantation failure (RIF), particularly in regard to the conflicting evidence reported by previous studies. Two reviewers independently searched Pubmed, MEDLINE, Web of Science, Cochrane Library and Embase to identify all publications of clinical trials of hysteroscopy with or without endometrial biopsy in RIF patients. The primary outcome measures were clinical pregnancy rate (CPR) and live birth rate (LBR). Pooled relative ratios (RRs) with 95% confidence intervals (CIs) were calculated. Publication bias was detected using funnel plots and Egger's regression tests. Six eligible studies comprising 4143 patients were included. The CPR and LBR were both significantly higher in RIF patients with OH than RIF patients without OH (CPR: RR 1.34, 95% CI 1.14–1.57, P < 0.05; LBR: RR 1.29, 95% CI 1.03–1.62, P < 0.05). Subgroup analysis revealed a significant association between OH and CPR in Asia (CPR: RR 1.49, 95% CI 1.31–1.69; P < 0.05) rather than in Europe (CPR: RR 1.08, 95% CI 0.93–1.26; P = 0.291). However, there was no evidence of a significant difference in either CPR or LBR between the normal and abnormal OH groups (CPR: RR 0.92, 95% CI 0.83–1.02, P = 0.12; LBR: RR 0.76, 95% CI 0.37–1.56, P = 0.450). Hysteroscopy may potentially improve pregnancy outcomes in patients with RIP. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly( l-lactic acid) (PLA) is now a very attractive polymer for food packaging applications. In this study, PLA/poly(trimethylene carbonate) (PTMC)/talc composite films were prepared by solvent casting. The influence of the talc loading (0, 1, 2, and 3 wt %) on the phase morphology of the PLA/PTMC/talc composites and the improvement in the resulting properties are reported in this article. The scanning electron microscopy images of the composite films demonstrated good compatibility between the PLA and PTMC, whereas talc was not thoroughly distributed in the PLA matrix at talc contents exceeding 3 wt %. The tensile strength and elongation at break of the composite films significantly improved ( p < 0.05). On the contrary, the water vapor permeability and oxygen properties of the composite films decreased by 24.7 and 39.2%, respectively, at the 2 wt % talc loading. Differential scanning calorimetry showed that the crystallinity of the PLA phase increased with the presence of talc filler in the PLA/PTMC/talc composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 40016. [ABSTRACT FROM AUTHOR]

The article discusses the origin of the Jinbaoshan platinum-palladium deposit in Western Yunnan, China and mentions their implications for the relationship between crustal contamination and mineralization. Topics discussed include analysis of the samples containing wehrlites and platinum group elements (PGE)rich ores, data revealing crustal contamination of the Jinbaoshan intrusion magma and a two-stage model defining the formation of the mineralization in the Jinbaoshan intrusion.