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31.
The local geese in the transition region between the Caucasus Mountains and Anatolia have economically significant differences in productivity and are identified by four feather colors, white, black, piebald, and yellow. This study was undertaken to determine the genetic structure, evolutionary relationships, and genetic diversity among these birds. DNA samples were obtained from 100 animals, and 50 random primers were screened. Genetic relationships were determined by random amplified polymorphic DNA polymorphisms obtained from a total of 48 loci, showing 40 bands (83.33%) that were polymorphic among all the populations investigated. A dendrogram constructed for this study revealed a close relationship between the white and the black birds. Additionally, the piebald birds showed close similarity to white and black geese, and the yellow birds displayed a clear distance from the other three populations.  相似文献   
32.
Cadmium and cobalt adsorption from aqueous solution onto calcium alginate, sodium alginate with an extracellular polysaccharide (EPS) produced by the activated sludge bacterium Chryseomonas luteola TEM05 and immobilized C. luteola TEM05 was studied. In addition, solutions containing both of these ions were prepared and partial competitive adsorption of these mixtures was investigated. Metal adsorption onto gel beads was carried out at pH 6.0 and 25 degrees C. The maximum adsorption capacities determined by fitting Langmuir isotherms to the data for calcium alginate, calcium alginate+EPS, calcium alginate + C. luteola TEM05 and calcium alginate + EPS + C. luteola TEM05 were 45.87, 55.25, 49.26, 51.81 mg g(-1) for Co(II) and 52.91, 64.10, 62.5, 61.73 mg g(-1) for Cd(II), respectively. The biosorption capacity of the carrier for both metal ions together in competition was lower than those obtained when each was present alone.  相似文献   
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This study investigates the predictive ability of gene-expression programming (GEP) in the estimation of methane yield (Ym) and effluent substrate (Se) produced by two anaerobic filters. The modeling study was carried out using the data obtained from two upflow anaerobic filters - one mesophilic (35 °C) and one thermophilic (55 °C) - operated for the treatment of paper-mill wastewater under varying organic loadings. The GEP model was composed of three inputs, hydraulic retention time (Thr), organic loading rate (Rol), and influent substrate (Si), and one output, either Se or Ym. The Stover-Kincannon model was also used for data analysis and to evaluate the prediction ability. Three statistical criteria, root mean square error (RMSE), determination coefficient (R2), and Akaike's information criteria (AIC), were the means used for comparison. The results showed that the GEP approach predicted the performance of both anaerobic filters much better than the Stover-Kincannon model.  相似文献   
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36.
In this study, a total of 5,094 ticks found on humans were examined in terms of species, development stage, gender, host features and seasonality for a year period. Of these ticks 17 were argasid and 5,077 were ixodid. Predominantly species of the ixodid genera Hyalomma, Dermacentor, Rhipicephalus and Haemaphysalis were found on humans in Ankara (Anatolia). Most abundant were Hyalomma nymphs (29.8%) and adults (28.2%). Primary factors in terms of tick bite risk were region, habitat and season.  相似文献   
37.

Background

Accurate prediction of dengue incidence levels weeks in advance of an outbreak may reduce the morbidity and mortality associated with this neglected disease. Therefore, models were developed to predict high and low dengue incidence in order to provide timely forewarnings in the Philippines.

Methods

Model inputs were chosen based on studies indicating variables that may impact dengue incidence. The method first uses Fuzzy Association Rule Mining techniques to extract association rules from these historical epidemiological, environmental, and socio-economic data, as well as climate data indicating future weather patterns. Selection criteria were used to choose a subset of these rules for a classifier, thereby generating a Prediction Model. The models predicted high or low incidence of dengue in a Philippines province four weeks in advance. The threshold between high and low was determined relative to historical incidence data.

Principal Findings

Model accuracy is described by Positive Predictive Value (PPV), Negative Predictive Value (NPV), Sensitivity, and Specificity computed on test data not previously used to develop the model. Selecting a model using the F0.5 measure, which gives PPV more importance than Sensitivity, gave these results: PPV = 0.780, NPV = 0.938, Sensitivity = 0.547, Specificity = 0.978. Using the F3 measure, which gives Sensitivity more importance than PPV, the selected model had PPV = 0.778, NPV = 0.948, Sensitivity = 0.627, Specificity = 0.974. The decision as to which model has greater utility depends on how the predictions will be used in a particular situation.

Conclusions

This method builds prediction models for future dengue incidence in the Philippines and is capable of being modified for use in different situations; for diseases other than dengue; and for regions beyond the Philippines. The Philippines dengue prediction models predicted high or low incidence of dengue four weeks in advance of an outbreak with high accuracy, as measured by PPV, NPV, Sensitivity, and Specificity.  相似文献   
38.
β-Galactosidase purified from the thermoacidophilic Alicyclobacillus acidocaldarius subsp. rittmannii isolated from Antarctica is a member of the GH42 family. The enzyme was not effected by various concentrations of its reaction product glucose, but was greatly inhibited by the other reaction product galactose using both substrates, ONPG and lactose. Linewever-Burk plot analysis derived from both ONPG and lactose hydrolysis results showed that galactose is a mixed-type inhibitor of the purified β-galactosidase. The enzyme was slightly activated by Mg2+ (13% at 20 mM), while inhibited at higher concentrations of Ca+2 (33% at 10 mM), Zn+2 (86% at 8 mM) and Cu+2 (87% at 4 mM). The enzyme activity was not significantly altered by the metal ion chelators EDTA and 1,10-phenanthroline up to 20 mM, indicating that this enzyme is not a metalloenzyme. 2-Mercaptoethanol and DTT were found to enhance β-galactosidase activity, while p-chloromercuribenzoic acid (PCMB) completely inhibited enzymatic activity (97% at 1 mM; 99.7% at 2 mM), indicating at least one essential Cys residue modified by the reagents in the active site of β-galactosidase. Iodoacetamide and Nethylmaleimide had little effect on the β-galactosidase. Phenylmethylsulfonyl fluoride (PMSF) inhibited the enzyme strongly (19.8% at 1 mM; 71.9% at 10 mM), also showing the participation of serine for enzyme activity.  相似文献   
39.
When bound to Escherichia coli ribosomes and irradiated with near-UV light, various derivatives of yeast tRNA(Phe) containing 2-azidoadenosine at the 3' terminus form cross-links to 23 S rRNA and 50 S subunit proteins in a site-dependent manner. A and P site-bound tRNAs, whose 3' termini reside in the peptidyl transferase center, label primarily nucleotides U2506 and U2585 and protein L27. In contrast, E site-bound tRNA labels nucleotide C2422 and protein L33. The cross-linking patterns confirm the topographical separation of the peptidyl transferase center from the E site domain. The relative amounts of label incorporated into the universally conserved residues U2506 and U2585 depend on the occupancy of the A and P sites by different tRNA ligands and indicates that these nucleotides play a pivotal role in peptide transfer. In particular, the 3'-adenosine of the peptidyl-tRNA analogue, AcPhe-tRNA(Phe), remains in close contact with U2506 regardless of whether its anticodon is located in the A site or P site. Our findings, therefore, modify and extend the hybrid state model of tRNA-ribosome interaction. We show that the 3'-end of the deacylated tRNA that is formed after transpeptidation does not immediately progress to the E site but remains temporarily in the peptidyl transferase center. In addition, we demonstrate that the E site, defined by the labeling of nucleotide C2422 and protein L33, represents an intermediate state of binding that precedes the entry of deacylated tRNA into the F (final) site from which it dissociates into the cytoplasm.  相似文献   
40.
Laccases (benzenediol: oxygen oxidoreductases, [EC1.10.3.2] are mostly known as members of the blue multicopper oxidase family that are used in very different industrial applications: textile, pulp and paper, food, cosmetics industries, bioremediation process, biosensor, biofuel and organic synthesis. Stability against the extreme conditions is an important property and it makes laccase suitable for several industrial processes. Laccase should have salt resistance to be used in textile dye degradation because the textile wastewaters include dyes with high concentrations of salts, especially NaCl. Bacterial laccases are preferable to be used for bioremediation process due to their high stability to extremely salt contaminated and alkalophilic environment. Bacillus subtilis LP2 was identified as a source of alkali-tolerant, salt resistant laccase. Laccase showed activity over a wide pH (4–10) and temperature (30–80?°C) range. Maximum laccase activity was observed as 140.4?U/mg (umol/min*mg) at pH 8 and 50?°C with the substrate guaiacol. Stability of laccase was determined as 60% and 20% after incubation of the enzyme for different time intervals of 20 and 40?min at 50?°C and pH 8. SDS (10?mM) and EDTA (5?mM) decreased laccase activity from 100% to 0% and 56%, respectively. Despite the other inhibitors, NaCI increased the activity of laccase to 167% at 500?mM concentration. Laccase from Bacillus subtilis LP2 barely showed the activity on the substrates vanillin and L-tyrosine. These results clearly show that laccase from Bacillus subtilis LP2 has high potential to be used for several applications in textile industry.  相似文献   
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