Toxicity of linear alkyl benzene sulphonate on some aquatic plants

The effect of different concentrations of linear alkyl benzene sulphonate under laboratory conditions on Salvinia molesta Mitchell, Hydrilla verticillata (L.f.) Royle, Ceratophyllum demursum L., Lemna minor L., Spirodella polyrhiza (L.) Schleid, and Pistia stratiotes L. was studied. A dose dependent effect on protein and chlorophyll a and b contents leading to substantial changes were noticed in the ultrastructural features as evident from scanning electron microscopy.     

Empirical feed formulations for the marine ornamental fish,striped damsel,Dascyllus aruanus (Linné 1758) and their physical,chemical and nutritional evaluation

Formulated feeds containing a common ingredient mixture (CIM) consisting of fishmeal (anchovies), shrimp meal (Acetes), squid meal (Loligo) and soybean meal incorporated in ascending levels to obtain protein levels ranging from 180 to 560 g kg^?1(18.34%, 25.35%, 36.27%, 46.61% and 56.28%) and an energy level of 19 MJ kg^?1 were fed to the marine ornamental fish, striped damsel, Dascyllus aruanus <200 mg and 200–300 mg in size for periods of 35 and 63 days. The <200 mg fish accepted particles <0.5 mm in size and showed maximum growth in terms of absolute growth rate (AGR), relative growth rate (RGR) and specific growth rate (SGR) with the feed containing 380 g kg^?1 CIM having a protein content of 362 g kg^?1. Second‐degree polynomial regression equations fitted confirmed these observations with a predicted requirement of 360 g kg^?1 protein. In fish weighing 200–300 mg, growth was not significantly different (P>0.05) in fish fed with feeds containing 380 and 580 g kg^?1 CIM with 360 and 470 g kg^?1 protein. With these data, the second‐degree polynomial regressions showed that a protein level of 464 g kg^?1 would result in an RGR of 107%. The feeds were well accepted by the damselfish, showing good colour retention and health.The cost of the feeds excluding processing costs ranges from US $ 1.35 to 3.36 kg^?1. This is the first report on the development of formulated feeds for damselfish that would help in rearing and aquarium keeping of damselfish worldwide.     

Molecular and Statistical Analysis of Campylobacter spp. and Antimicrobial‐Resistant Campylobacter Carriage in Wildlife and Livestock from Ontario Farms

The objectives of this study were to (i) compare the carriage of Campylobacter and antimicrobial‐resistant Campylobacter among livestock and mammalian wildlife on Ontario farms, and (ii) investigate the potential sharing of Campylobacter subtypes between livestock and wildlife. Using data collected from a cross‐sectional study of 25 farms in 2010, we assessed associations, using mixed logistic regression models, between Campylobacter and antimicrobial‐resistant Campylobacter carriage and the following explanatory variables: animal species (beef, dairy, swine, raccoon, other), farm type (swine, beef, dairy), type of sample (livestock or wildlife) and Campylobacter species (jejuni, coli, other). Models included a random effect to account for clustering by farm where samples were collected. Samples were subtyped using a Campylobacter‐specific 40 gene comparative fingerprinting assay. A total of 92 livestock and 107 wildlife faecal samples were collected, and 72% and 27% tested positive for Campylobacter, respectively. Pooled faecal samples from livestock were significantly more likely to test positive for Campylobacter than wildlife samples. Relative to dairy cattle, pig samples were at significantly increased odds of testing positive for Campylobacter. The odds of isolating Campylobacter jejuni from beef cattle samples were significantly greater compared to dairy cattle and raccoon samples. Fifty unique subtypes of Campylobacter were identified, and only one subtype was found in both wildlife and livestock samples. Livestock Campylobacter isolates were significantly more likely to exhibit antimicrobial resistance (AMR) compared to wildlife Campylobacter isolates. Campylobacter jejuni was more likely to exhibit AMR when compared to C. coli. However, C. jejuni isolates were only resistant to tetracycline, and C.  coli isolates exhibited multidrug resistance patterns. Based on differences in prevalence of Campylobacter spp. and resistant Campylobacter between livestock and wildlife samples, and the lack of similarity in molecular subtypes and AMR patterns, we concluded that the sharing of Campylobacter species between livestock and mammalian wildlife was uncommon.     

Complete genome characterization of Sugarcane yellow leaf virus from India: Evidence for RNA recombination

Yellow leaf (YL) caused by Sugarcane yellow leaf virus (SCYLV) has become a serious constraint for sugarcane production in different countries. Worldwide seven genotypes have been reported, with five based on complete and two based on partial genome characterization. We have previously reported the occurrence of three different SCYLV genotypes in India based on their partial genome sequences. A further four SCYLV isolates from sugarcane from Coimbatore (in India) were characterized after complete genome sequencing (~ 5,875 nt). These isolates (SCYLV-IND) exhibited amino acid (aa) sequence differences of 29.2–31.8, 28.1–34.4 and 30.7–33.4 % with REU, HAW-PER and BRA in partial ORF0 sequences, respectively. Similarly IND isolates have 21.4–23.7, 22.5–25.0 and 21.4–23.9 % aa sequence differences with REU, HAW-PER and BRA, respectively in partial ORF1. However, the difference was found to be least in ORF5. The genotype reported from China, CHN1 shared a very close relationship with IND isolates with minimum differences of 4.3–5.3 %, 4.8–5.8 % and 2.5–3.0 % in ORF0, 1 and 5 in aa sequences, respectively and 4.4–5.3 % in complete nucleotide sequences. Phylogenetic analyses showed a separate lineage for IND isolates. Evidence of recombination was found in ORF1 to ORF5 with the maximum number of sites occurring in ORF2. The high incidence of SCYLV recombination suggests that recombination plays an important role in SCYLV evolution.     

Combinatorial electrochemistry: A highly parallel, optical screening method for discovery of better electrocatalysts

Combinatorial screening of electrochemical catalysts by current-voltage methods can be unwieldy for large sample sizes. By converting the ions generated in an electrochemical half-cell reaction to a fluorescence signal, the most active compositions in a large electrode array have been identified. A fluorescent acid-base indicator was used to image high concentrations of hydrogen ions, which were generated in the electrooxidation of methanol. A 645-member electrode array containing five elements (platinum, ruthenium, osmium, iridium, and rhodium), 80 binary, 280 ternary, and 280 quaternary combinations was screened to identify the most active regions of phase space. Subsequent "zoom" screens pinpointed several very active compositions, some in ternary and quaternary regions that were bounded by rather inactive binaries. The best catalyst, platinum(44)/ruthenium(41)/osmium(10)/iridium(5) (numbers in parentheses are atomic percent), was significantly more active than platinum(50)/ruthenium(50) in a direct methanol fuel cell operating at 60 degreesC, even though the latter catalyst had about twice the surface area of the former.