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In the event of a natural disaster or other unexpected devastation, the need arises for a means of waste treatment and removal. In the case of agricultural waste, specifically poultry, safe and eff...

Ileocecal resection (ICR) is a commonly required surgical intervention in unmanageable Crohn's disease and necrotizing enterocolitis. However, the impact of ICR, and the concomitant doses of antibiotic routinely given with ICR, on the intestinal commensal microbiota has not been determined. In this study, wild-type C57BL6 mice were subjected to ICR and concomitant single intraperitoneal antibiotic injection. Intestinal lumen contents were collected from jejunum and colon at 7, 14, and 28 days after resection and compared to non-ICR controls. Samples were analyzed by16S rRNA gene pyrosequencing and quantitative PCR. The intestinal microbiota was altered by 7 days after ICR and accompanying antibiotic treatment, with decreased diversity in the colon. Phylogenetic diversity (PD) decreased from 11.8 ± 1.8 in non-ICR controls to 5.9 ± 0.5 in 7-day post-ICR samples. There were also minor effects in the jejunum where PD values decreased from 8.3 ± 0.4 to 7.5 ± 1.4. PCoA analysis indicated that bacterial populations 28 days post-ICR differed significantly from non-ICR controls. Moreover, colon and jejunum bacterial populations were remarkably similar 28 days after resection, whereas the initial communities differed markedly. Firmicutes and Bacteroidetes were the predominant phyla in jejunum and colon before ICR; however, Firmicutes became the vastly predominant phylum in jejunum and colon 28 days after ICR. Although the microbiota returned towards a homeostatic state, with re-establishment of Firmicutes as the predominant phylum, we did not detect Bacteroidetes in the colon 28 days after ICR. In the jejunum Bacteroidetes was detected at a 0.01% abundance after this time period. The changes in jejunal and colonic microbiota induced by ICR and concomitant antibiotic injection may therefore be considered as potential regulators of post-surgical adaptive growth or function, and in a setting of active IBD, potential contributors to post-surgical pathophysiology of disease recurrence. © 2013 Devine et al.

Using biochemical and molecular methods, this research determined whether or not the H(2)S test did correctly identify sewage-contaminated waters by being the first to use culturing and molecular methods to identify the types and numbers of fecal indicator organisms, pathogens, and other microbes present in sewage samples with positive H(2)S test results. For the culture-based method, samples were analyzed for the presence of fecal bacteria by spread plating the sewage sample onto differential and selective media for Aeromonas spp., Escherichia coli, sulfite-reducing clostridia, H(2)S-producing bacteria, and Salmonella/Shigella spp. The isolates were then: (1) tested to determine whether they were H(2)S-producing organisms and (2) identified to the genus and species level using biochemical methods. The molecular method used to characterize the microbial populations of select samples was terminal restriction fragment length polymorphisms. These experiments on sewage provided evidence that positive H(2)S tests consistently contained fecal bacteria and pathogens. There were strong relationships of agreement between the organisms identified by both methods tested. This study is an important advance in microbial water quality detection since it is focused on the evaluation of a novel, low-cost, water microbiology test that has the potential to provide millions of people worldwide access to water quality detection technology. Of prime consideration in evaluating water quality tests is the determination of the test's accuracy and specificity, and this article is a fundamental step in providing that information.

The sensitivity and specificity of the H(2)S test to detect fecal bacteria in water has been variable and uncertain in previous studies, partly due to its presence-absence results. Furthermore, in groundwater samples false-positive results have been reported, with H(2)S-positive samples containing no fecal coliforms or Escherichia coli. False-negative results also have been reported in other studies, with H(2)S-negative samples found to contain E. coli. Using biochemical and molecular methods and a novel quantitative test format, this research identified the types and numbers of microbial community members present in natural water samples, including fecal indicators and pathogens as well as other bacteria. Representative water sources tested in this study included cistern rainwater, a protected lake, and wells in agricultural and forest settings. Samples from quantitative H(2)S tests of water were further cultured for fecal bacteria by spread plating onto the selective media for detection and isolation of Aeromonas spp., E. coli, Clostridium spp., H(2)S-producers, and species of Salmonella and Shigella. Isolates were then tested for H(2)S production, and identified to the genus and species level using biochemical methods. Terminal Restriction Fragment Length Polymorphisms (TRFLP) was the molecular method employed to quantitatively characterize microbial community diversity. Overall, it was shown that water samples testing positive for H(2)S bacteria also had bacteria of likely fecal origin and waters containing fecal pathogens also were positive for H(2)S bacteria. Of the microorganisms isolated from natural water, greater than 70 percent were identified using TRFLP analysis to reveal a relatively stable group of organisms whose community composition differed with water source and over time. These results further document the validity of the H(2)S test for detecting and quantifying fecal contamination of water.

Die Titelverbindung (II) unterliegt bei Behandlung mit LiAl-hydrid, Phenyl-Li, Phenyl-MgBr oder athanolischer NaOH nucleophilen Ringoffnungsreaktionen, die zu den Produkten (Ia), (Ib) bzw. (Ic) und (Id) fuhren.

Ring-opening of 1,3-dimethyl-1,3-diphenyl- and 1,1,3,3-tetraphenyl-1,3-disilacyclobutane takes place on treatment with halogens, hydrogen halides, lithium aluminium hydride, sodium hydroxide, or sulphuric acid, but the reactions with halogens and hydrogen halides are complicated by silicon-phenyl bond scission. 1,1 -Dimethyl-3,3-diphenyl-1,3-disilacyclobutane is conveniently prepared by reaction of an equimolar mixture of the silanes Me2SiCl·CH2Cl and Ph2SiCl·CH2Cl in tetrahydrofuran with magnesium. It reacts with hydroxide, methoxide, ethoxide, hydride ion, hydrogen chloride, or hydrogen bromide to give major products arising via SiMe2–CH2 bond scission, but in contrast it reacts with chlorine or bromine to give major products arising via SiPh2–CH2 bond scission.

1,1,3,3-Tetramethyl-1,3-disilacyclobutane. (I), reacts with halogens, hydrogen halides, sulphuric acid, lithium tetrahydridoaluminate, phenyl-lithium, phenylmagnesium bromide, ethanolic silver(I) nitrate, ethanolic mercury(II) chloride, and ethanolic mercury(II) acetate to give ring-opened products in high yields; (I) is unaffected by trifluoroiodomethane, N-bromosuccinimide, benzenethiol, heptan-1-ol, basic alumina, sulphur, phenylmercury chloride, or mercury(II) acetate in benzene. Photochemical reaction of t-butyl hypochlorite with (I) gives comparable amounts of 1 -chloromethyl-1,3,3-trimethyl-, 2-chloro-1,1,3,3-tetramethyl-, and 2,2-dichloro-1,1,3,3-tetramethyl-1,3-disilacyclobutane, together with lesser amounts of the ring-opened hydrogen chloride and chlorine 1 : 1 adducts.

1,1,3,3-Tetramethyl-1,3-disilacyclobutane, (I), reacts with iodine monochloride or sodium benzenethiolate in benzenethiol to give reasonable yields of ring-opened 1 :1 adducts, while reaction with bromobis(trifluoromethyl)-amine affords a mixture of perfluoro-2-azapropene and 1-bromo-4-fluoro-2,2.4-trimethyl-2,4-disilapentane via decomposition of the initially formed 1:1 adduct. 1,3-Dimethyl-1,3-diphenyl-1,3-disilacyclobutane, (II), reacts similarly with sodium benzenethiolate in benzenethiol and the bromoamine, but reaction with iodine mono-chloride affords mainly polymeric material. The reaction of sulphur trioxide with compound (II) results in insertion into a ring Si–CH2 bond and a Si–Ph bond in the ratio 9 : 90, while reaction with 1,1,3,3-tetraphenyl-1,3-disila-cyclobutane, (III), gives the Si–Ph insertion product exclusively. Both the phenyl-substituted disilacyclobutanes react with mercury(II) acetate in ethanol to give ring-opened products of the type AcO·Hg·CH2·[graphic omitted]i·CH2·[graphic omitted]i·OEt in high yield.

1,1,3,3-Tetramethyl-1,3-disilacyclobutane, (I), reacts with trichlorosilane or dichloro(methyl)silane in the presence of hexachloroplatinic(IV) acid to give the chlorine-exchange adducts, Me2SiCl·CH2·SiMe2·CH2·SiHCl2(80%) or Me2SiCl·CH2·SiMe2·CH2·SiMeHCl (61%); in the latter reaction the hydrogen-exchange adduct, Me2SiH·CH2·SiMe2·CH2·SiMeCl2(5%). is also formed. A comparable reaction of 1.3-dimethyl-1.3-diphenyl-1,3-disilacyclobutane, (II), with trichlorosilane gives mainly polymeric material together with the chlorine-exchange adduct (10%). Both silacyclobutanes react with tin(IV) chloride in the absence of catalyst or with trimethylsilanol to afford ring-opened 1 :1 adducts in high yield. Compound (I) also reacts with triphenylsilanol to afford hexaphenyldisiloxane and 1,1,3,3-tetramethyl-1,3-bis(trimethylsilylmethyl)disiloxane (87%); (II) does not react under comparable conditions.