Chemical Cleaning of Coal with Hot Alkaline Solutions

Various bituminous coals were demineralized by an experimental two-step leaching process in which the ballmilled coals were first treated with a hot alkaline solution and then with a dilute mineral acid. Different alkalis and acids were studied to determine their relative effectiveness. In addition, the effects of alkali concentration, treatment temperature, and treatment time were evaluated. Under the best conditions, the process reduced the ash content of the coals by 85-90% and the total sulfur content by 70-90%. As the temperature of the alkaline treatment was raised from 150 to 345°C, the removal of sulfur increased greatly whereas the recovery of organic matter declined. When a 1 M sodium carbonate solution was employed for the treatment, the recovery of organic matter was 91-97% for various coals treated at 250°C and 79-89% for the same coals treated at 300°C

Identification of essential histidine residues in a recombinant alpha-amylase of thermophilic and alkaliphilic Bacillus sp strain TS-23

To understand the structure-function relationships of a truncated Bacillus sp. strain TS-23 alpha-amylase, each of His-137, His-191, His-239, His-269, His-305, His-323, His-361, His-436, and His-475 was replaced with leucine. The molecular masses of the purified wild-type and mutant enzymes were approximately 54 kDa. The specific activity of His323Leu and His436Leu was decreased by more than 52%, while His239Leu, His305Leu, and His475Leu showed activity similar to that of the wild-type enzyme. As compared with the wild-type enzyme, His323Leu and His436Leu exhibited a 62% decrease in the value of k(cat)/K-m. Alterations in His-191, His-239, His-305, and His-475 did not cause a significant change in the K-m or k(cat) values. At 70degreesC, a decreased half-life was observed in His436Leu. These results indicate that His-137, His-269, and His-361 of Bacillus sp. strain TS-23 alpha-amylase are important for proper catalytic activity and that His-436 may contribute to the thermostability of the enzyme

Evaluation of SPARC as a candidate gene of juvenile-onset primary open-angle glaucoma by mutation and copy number analyses

Purpose: To investigate the involvement of SPARC (secreted protein acidic and rich in cysteine) mutations and copy number variation in juvenile-onset primary open-angle glaucoma (JPOAG). Methods: This study involved the 27 family members from the GLC1M (glaucoma 1, open angle, M)-linked Philippine pedigree with JPOAG, 46 unrelated Chinese patients with JPOAG and 95 controls. Mutation screening of the SPARC sequence, covering the promoter, 5′-untranslated region (UTR), entire coding regions, exon-intron boundaries, and part of the 3′-UTR, was performed using polymerase chain reaction and direct DNA sequencing. Copy number of the gene was analyzed by three TaqMan copy number assays. Results: No putative SPARC mutation was detected in the Philippine family. In the Chinese participants, 11 sequence variants were detected. Two were novel: IVS2+8G>T and IVS2+32C>T. For the 9 known SNPs, one was synonymous (rs2304052, p.Glu22Glu) and the others were located in noncoding regions. No individual SNP was associated with JPOAG. Five of the most common SNPs, i.e., rs2116780, rs1978707, rs7719521, rs729853, and rs1053411, were contained in a LD (linkage disequilibrium) block. Haplotype-based analysis showed that no haplotype was associated with the disorder. Copy number analysis revealed that all study subjects had two copies of the gene, suggesting no correlation between the copy number of SPARC and JPOAG. Conclusions: We have excluded SPARC as the causal gene at the GLC1M locus in the Philippine pedigree and, for the first time, revealed that the coding sequences, splice sites and copy number of SPARC do not contribute to JPOAG. Further investigations are warranted to unravel the involvement of SPARC in the pathogenesis of other forms of glaucoma

SNP rs1533428 at 2p16.3 as a marker for late-onset primary open-angle glaucoma

Purpose: To investigate the associations between gene variants in cholesterol 24S-hydroxylase (CYP46A1), LIM homeobox transcription factor 1-beta (LMX1B), plexin domain containing 2 (PLXDC2), toll-like receptor 4 (TLR4), transmembrane and tetratricopeptide repeat containing 2 (TMTC2), zona pellucida glycoprotein 4 (ZP4), chromosome 2p16.3, and primary open-angle glaucoma (POAG). Methods: We studied 462 POAG patients and 577 controls from three cohorts (Hong Kong, Shantou, and Beijing, China). Twelve single-nucleotide polymorphisms (SNPs) were genotyped in the Hong Kong cohort using TaqMan genotyping assay. Significant associations were validated in the Shantou and Beijing cohorts. Results: Association of POAG with TLR4 rs7037117, in a recessive model, was identified in the Hong Kong and Shantou cohorts (both southern Chinese, $p_{rec}$=0.0019) but not the Beijing cohort (northern Chinese). rs1533428 at chromosome 2p16.3 showed a consistent trend of age-specific association in all three cohorts. Genotypes TT + CT conferred a 2.16 fold of significantly increased risk to late-onset POAG ($p_{dom}$=0.00025), but no significant risk to POAG of younger ages of onset in the combined cohort. A joint effect was found between rs7037117 and rs1533428, with carriers of both higher-risk genotypes having a 4.53 fold of increased disease risk (p=0.00028). Conclusions: Our study reveals discrepant association patterns of 12 candidate SNPs in 7 genes/loci with POAG in Chinese, provides positive replications for POAG markers rs1533428 at 2p16.3 and TLR4 rs7037117, and suggests that rs1533428 is a putative risk variant for late-onset POAG. The identification of an age-specific association between rs1533428 and late-onset POAG highlights a new genotype-phenotype association in POAG. Further studies are warranted to confirm the age-specific association

A Hadron Blind Detector for the PHENIX Experiment

A novel Hadron Blind Detector (HBD) has been developed for an upgrade of the PHENIX experiment at RHIC. The HBD will allow a precise measurement of electron-positron pairs from the decay of the light vector mesons and the low-mass pair continuum in heavy-ion collisions. The detector consists of a 50 cm long radiator filled with pure CF4 and directly coupled in a windowless configuration to a triple Gas Electron Multiplier (GEM) detector with a CsI photocathode evaporated on the top face of the first GEM foil.Comment: 4 pages, 3 figures, Quark Matter 2005 conference proceeding

Design, Construction, Operation and Performance of a Hadron Blind Detector for the PHENIX Experiment

A Hadron Blind Detector (HBD) has been developed, constructed and successfully operated within the PHENIX detector at RHIC. The HBD is a Cherenkov detector operated with pure CF4. It has a 50 cm long radiator directly coupled in a window- less configuration to a readout element consisting of a triple GEM stack, with a CsI photocathode evaporated on the top surface of the top GEM and pad readout at the bottom of the stack. This paper gives a comprehensive account of the construction, operation and in-beam performance of the detector.Comment: 51 pages, 39 Figures, submitted to Nuclear Instruments and Method

Neutrino flux calculations for the AGS narrow band beam

Presented are results of calculations of nu/sub ..mu../ fluxes in the AGS neutrino beam with the new dichromatic horn. The wide band beam nu/sub ..mu../, as well as the nu/sub e/ backgrounds, are discussed. The nu/sub e//nu/sub ..mu../ ratio is about 8 x 10/sup -3/. The possible sources and magnitudes of uncertainties are discussed. Finally, the calculated fluxes are compared with beam measurements

Au+Au Reactions at the AGS: Experiments E866 and E917

Particle production and correlation functions from Au+Au reactions have been measured as a function of both beam energy (2-10.7AGeV) and impact parameter. These results are used to probe the dynamics of heavy-ion reactions, confront hadronic models over a wide range of conditions and to search for the onset of new phenomena.Comment: 12 pages, 14 figures, Talk presented at Quark Matter '9