Cloning,heterologous expression,and characterization of recombinant class II cytochromes c from Rhodopseudomonas palustris

The cytochrome (cyt) c', cyt c(556), and cyt c(2) genes from Rhodopseudomonas palustris have been cloned; recombinant cyt c' and cyt c(556) have been expressed, purified, and characterized. Unlike mitochondrial cyt c, these two proteins are structurally similar to cyt b(562), in which the heme is embedded in a four-helix bundle. The hemes in both recombinant proteins form covalent thioether links to two Cys residues. UV/vis spectra of the Fe(II) and Fe(III) states of the recombinant cyts are identical with those of the corresponding native proteins. Equilibrium unfolding measurements in guanidine hydrochloride solutions confirm that native Fe(II)-cyt c(556) is more stable than the corresponding state of Fe(III)-cyt c(556) (DeltaDeltaG(f)(o) =22 kJ/mol).     

Tests of proportional hazards and proportional odds models for grouped survival data

In this paper, we derive score test statistics to discriminate between proportional hazards and proportional odds models for grouped survival data. These models are embedded within a power family transformation in order to obtain the score tests. In simple cases, some small-sample results are obtained for the score statistics using Monte Carlo simulations. Score statistics have distributions well approximated by the chi-squared distribution. Real examples illustrate the proposed tests.     

Environmental assessment of energy production from municipal solid waste incineration

Background, Aims and Scope During the combustion of municipal solid waste (MSW), energy is produced which can be utilized to generate electricity. However, electricity production from incineration has to be evaluated from the point view of the environmental performance. In this study, environmental impacts of electricity production from waste incineration plant in Thailand are compared with those from Thai conventional power plants. Methods The evaluation is based on a life cycle perspective using life cycle assessment (LCA) as the evaluation tool. Since MSW incineration provides two services, viz., waste management and electricity production, the conventional power production system is expanded to include landfilling without energy recovery, which is the most commonly used waste management system in Thailand, to provide the equivalent function of waste management. Results The study shows that the incineration performs better than conventional power plants vis-à-vis global warming and photochemical ozone formation, but not for acidification and nutrient enrichment. Discussion There are some aspects which may influence this result. If landfilling with gas collection and flaring systems is included in the analysis along with conventional power production instead of landfilling without energy recovery, the expanded system could become more favorable than the incineration in the global warming point of view. In addition, if the installation of deNO_x process is employed in the MSW incineration process, nitrogen dioxide can be reduced with a consequent reduction of acidification and nutrient enrichment potentials. However, the conventional power plants still have lower acidification and nutrient enrichment potentials. Conclusions The study shows that incineration could not play the major role for electricity production, but in addition to being a waste management option, could be considered as a complement to conventional power production. To promote incineration as a benign waste management option, appropriate deNO_x and dioxin removal processes should be provided. Separation of high moisture content waste fractions from the waste to be incinerated and improvement of the operation efficiency of the incineration plant must be considered to improve the environmental performance of MSW incineration. Recommendations This study provides an overall picture and impacts, and hence, can support a decision-making process for implementation of MSW incineration. The results obtained in this study could provide valuable information to implement incineration. But it should be noted that the results show the characteristics only from some viewpoints. Outlook Further analysis is required to evaluate the electricity production of the incineration plant from other environmental aspects such as toxicity and land-use.     

Genetic analysis of hybridization between white-handed (Hylobates lar) and pileated (Hylobates pileatus) gibbons in a contact zone in Khao Yai National Park,Thailand

Primates - Natural hybridization has played various roles in the evolutionary history of primates. Its consequences range from genetic introgression between taxa, formation of hybrid zones, and...     

Nonaspiration fine needle cytology and its histologic correlation in canine skin and soft tissue tumors.

OBJECTIVE: To analyze the findings of nonaspiration fine needle (NAFN) cytology as compared with the histopathologic findings in evaluating canine skin and soft tissue tumors. STUDY DESIGN: NAFN (21-27 gauge) cytology was performed on 213 cases. Smears were air dried and stained by the Rosenfeld method (May-Grünwald-Giemsa modification). Histopathologic evaluation was available for comparison in 40% of cases. RESULTS: NAFN cytology and histopathology results were compared in 85 dogs. The size of the 117 lesions varied from 0.5 to 2 cm (n=39), 2.1 to 5 cm (n=43), and > or = 5.1 (n=35). There were 22 nonneoplastic lesions, mostly inflammatory processes and cysts. Neoplastic lesions were classified as epithelial (36%), mesenchymal (30%), round cell tumor (n=13) and melanocytic (2%). Among 40 malignant lesions, mast cell tumor (n=14) and hemangiopericytoma (n=9) were the most frequent. Lipoma (n=14) and trichoblastoma (n=10) were the most common benign neoplastic lesions. Cytology showed sensitivity of 89%, specificity of 100%, positive and negative predictive value of 100% and 96%, respectively, and efficacy of 97%. CONCLUSION: NAFN cytology is extremely useful and accurate. It is safe and avoids the use of anesthesia. Further, it is easy to perform and noninvasive and usually provides a high-quality sample.     

Phylogeography and ecological niche modeling reveal evolutionary history of Leiolepis ocellata (Squamata,Leiolepidae)

Leiolepis ocellata is a lizard species distributing in topographically diverse habitats in northern Thailand. To explore its evolutionary history, 113 samples of L. ocellata were collected from 11 localities covering its distributional range in northern Thailand, and sequenced for mtDNA fragments (Cyt b and ND2). Pairwise comparisons across sampling localities yielded significant genetic differentiation (F _ST and Jost''s D) but no clear pattern of isolation by distance could be demonstrated based on the Mantel test. Phylogenetic and network analyses highlighted six haplogroups. Their divergence times were estimated to occur during the Pleistocene, much more recent than major orogenic events affecting northern Thailand. Instead, the results suggested that lineage divergences, of particularly eastern and western haplogroups of the region, coincided with the major rivers in the region (Yom river and Ping river, respectively), indicating vicariance in response to riverine barriers. Furthermore, ecological niche modeling suggested an expansion of suitable habitats of L. ocellata, when LGM‐liked conditions. This expansion potentially facilitated their dispersal among adjacent localities leading to lineage diversification and genetic admixture, after the riverine divergence.