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This research is to develop dictated metrics using a multi-proxy approach such as spatial–temporal analysis, statistical evaluation, and hydrogeochemical analysis. We have collected 45 groundwater samples located in the Tamirabarani river basin. To evaluate the aptness of developed metrics for agriculture and domestic needs and eleven years dataset has been analyzed and compared with national and international standards BIS, ICMAR, and WHO Monitoring and all the analysis results revealed that the concentration of calcium (Ca-1679 to 4937 mg/L; and Cl ions 236 to 1126 mg/L) and chloride ions was on the higher side in locations. These higher values may be attributed to the regional point sources as untreated water disposal and off-peak sources as agriculture practices. According to the results of the principal component analysis, the post-monsoon season accounted for an 84.2% variance. The major analyzed cations and anions have been observed in the following order: Na+ > Ca2+ > Mg2+ > K+ and Cl− > HCO3− > SO42− > NO3− respectively. Ca-Mg-HCO3, Mg-Ca–Cl, Na-C1, and infused waters have been discovered in the basin region, indicating that anion and cation dominance is not prevalent. This specifies that groundwater quality in this region is significantly degraded and suffers from extensive salinity due to the urban pollutants mixed with unprotected river sites. [ABSTRACT FROM AUTHOR]

At present, the error control process of the complex thin-walled workpiece mainly adopts the error suppression and error elimination; the effectiveness of error control depends on the cognition of the process designer about machine accuracy and the error-generating mechanism. This paper proposes a new compensation method to control errors in machining thin-walled workpieces based on the inverse reconstruction model. In this method, the thin-walled workpiece is represented by discrete point cloud (DPC) for error analysis; according to the unified error prediction model, the DPC positions can be obtained companying with the machining errors. Then the new DPC is reconstructed into the workpiece model used inverse reconstruction model. At the same time, a fairing algorithmis developed to deal with the smoothing problem of DPC. So, the new workpiece model is used instead of the original for processing. By this method, the machining precision and surface quality of thin-walled workpieces are ensured. In addition, a case study is presented to demonstrate the effectiveness of the method. [ABSTRACT FROM AUTHOR]

Expression levels measured in microarrays of oligonucleotide probes have now been adapted as a high throughput approach for identifying DNA sequence variation between genotypes, referred to as single feature polymorphisms (SFPs). Although there have been increasing interests in this approach, there is still need for improving the algorithm in order to achieve high sensitivity and specificity especially with complex genome and large datasets, while maintaining optimal computational performance. We obtained microarray datasets for expression profiles of two rice cultivars and adapted a median polish method to detect SFPs. The analysis identified 6,655 SFPs between two the rice varieties representing 3,131 rice unique genes. We showed that the median polish method has the advantage of avoiding fitting complex linear models thus can be used to analyze complex transcriptome datasets like the ones in this study. The method is also superior in sensitivity, accuracy and computing time requirement compared with two previously used methods. A comparison with data from a resequencing project indicated that 75.6% of the SFPs had SNP supports in the probe regions. Further comparison revealed that SNPs in sequences immediately flanking the probes also had contributions to the detection of SFPs in cases where the probes and the targets had perfectly matched sequences. It was shown that differences in minimum free energies caused by flanking SNPs, which may change the stability of RNA secondary structure, may partly explain the SFPs as detected. These SFPs may facilitate gene discovery in future studies. [ABSTRACT FROM AUTHOR]

KT/HAK/KUP potassium transporter protein-encoding genes constitute a large family in the plant kingdom. The KT/HAK/KUP family is important for various physiological processes of plant life. In this study, we identified 27 potential KT/HAK/KUP family genes in rice ( Oryza sativa) by database searching. Analysis of these KT/HAK/KUP family members identified three conserved motifs with unknown functions, and 11–15 trans-membrane segments, most of which are conserved. A total of 144 putative cis-elements were found in the 2 kb upstream region of these genes, of which a Ca2+-responsive cis-element, two light-responsive cis-elements, and a circadian-regulated cis-element were identified in the majority of the members, suggesting regulation of these genes by these signals. A comprehensive expression analysis of these genes was performed using data from microarrays hybridized with RNA samples of 27 tissues covering the entire life cycle from three rice genotypes, Minghui 63, Zhenshan 97, and Shanyou 63. We identified preferential expression of two OsHAK genes in stamen at 1 day before flowering compared with all the other tissues. OsHAK genes were also found to be differentially upregulated or downregulated in rice seedlings subjected to treatments with three hormones. These results would be very useful for elucidating the roles of these genes in growth, development, and stress response of the rice plant. [ABSTRACT FROM AUTHOR]

Abstract  Thioredoxin (Trx) proteins play important biological functions in cells by changing redox via thioldisulfied exchange. This system is especially widespread in plants. Through database search, we identified 30 potential Trx protein-encoding genes (OsTrx) in rice (Oryza sativa L.). An analysis of the complete set of OsTrx proteins is presented here, including chromosomal location, conserved motifs, domain duplication, and phylogenetic relationships. Our findings suggest that the expansion of the Trx gene family in rice, in large part, occurred due to gene duplication. A comprehensive expression profile of Trx genes family was investigated by analyzing the signal data of this family extracted from the whole genome microarray analysis of Minghui 63 and Zhenshan 97, two indica parents, and their hybrid Shanyou 63, using 27 different tissues representing the entire life cycle of rice. Results revealed specific expression of some members at germination transition as well as the 3-leaf stage during the vegetative growth phase of rice. OsTrx genes were also found to be differentially up- or down-regulated in rice seedlings subjected to treatments of phytohormones and light/dark conditions. The expression levels of the OsTrx genes in the different tissues and under different treatments were also checked by RT-PCR analysis. The identification of OsTrx genes showing differential expression in specific tissues among different genotypes or in response to different environmental cues could provide a new avenue for functional analyses in rice. [ABSTRACT FROM AUTHOR]

Laser surface melting was used to treat electro-metallurgic WC/steel composites. The microstructure and properties of the melted zone were investigated. It was found that a homogenous and fine microstructure was formed in the melted zone. A significant phase precipitated was the herringbone eutectic carbide of Fe3W3C. The volume fraction of the eutectics was related to the thermal absorption increasing with the decrease of scanning rate. Preheating was beneficial to form the orientation dendrite structure and to increase the volume fraction of the eutectics. The laser melted surface possessed better microhardness and wear resistance compared to the substrate. The volume fraction of the eutectics played an important role on the wear resistance which increased with the increase of the volume fraction of the eutectics. The wear resistance was mainly depended on the content of the primary WC, as increased with the increase of the content of WC. The improvement of interface bonding, fine eutectic precipitation and structure refinement etc. were regarded as the micro-mechanism of enhancing the surface properties. [ABSTRACT FROM AUTHOR]