Kinetics of dose-response relationship in the bimodal respiration of Colisa lalia (Hamilton-Buchanan) exposed to lindane (γ-BHC)

Acute bioassay tests were conducted with the organochlorine pesticide, lindane on Colisa lalia. LC50 and its 95% upper and lower confidence limits for different periods of exposure were determined. A toxicity curve was constructed from which is derived the lethal threshold concentration for Colisa to lindane. The fish were exposed to two selected concentrations viz., 0.1 and 0.37 mg 1^?1 for 96 and 6 h respectively and their behaviour and bimodal respiration were studied. Erratic behavioural responses were noticed at 0.37 mg 1^?1 whereas the response at 0.1 mg 1^?1 were orderly and adaptive. Total oxygen consumption of fish increased but the dependence on the type of respiration differed in the two concentrations, and this selective dependence at 0.1 mg 1^?1 is suggested to have survival value.     

A comparison of a 30-cluster survey method used in India and a purposive method in the estimation of immunization coverages in Tamil Nadu

The reaction mechanisms of p-nitrophenyl phosphate hydrolysis catalyzed by two rat liver isoenzymes of the low M(r) phosphotyrosine protein phosphatase (AcP1 and AcP2) were compared. Furthermore, the effect of some heterocyclic compounds on their activities were tested. Cyclic GMP and guanosine causes a particularly high activation of the isoenzyme AcP2, whereas its effect on AcP1 is very poor. A study on the mechanism of cyclic GMP activation was carried out. The results suggest that cyclic GMP activates the AcP2 isoenzyme by increasing the rate of the step that leads to the hydrolysis of the covalent enzyme-substrate phosphorylated complex formed during the catalytic process. The physiological significance of cyclic GMP activation of only one of the two isoenzymes (AcP2) remains uncertain.     

A Halogen-Bonded Organic Framework (XOF) Emissive Cocrystal for Acid Vapor and Explosive Sensing,and Iodine Capture

There is a strong and urgent need for efficient materials that can capture radioactive iodine atoms from nuclear waste. This work presents a novel strategy to develop porous materials for iodine capture by employing halogen bonding, mechanochemistry and crystal engineering. 3D halogen-bonded organic frameworks (XOFs) with guest-accessible permanent pores are exciting targets in crystal engineering for developing functional materials, and this work reports the first example of such a structure. The new-found XOF, namely TIEPE-DABCO , exhibits enhanced emission in the solid state and turn-off emission sensing of acid vapors and explosives like picric acid in nanomolar quantity. TIEPE-DABCO captures iodine from the gas phase (3.23 g g⁻¹ at 75 °C and 1.40 g g⁻¹ at rt), organic solvents (2.1 g g⁻¹), and aqueous solutions (1.8 g g⁻¹ in the pH range of 3–8); the latter with fast kinetics. The captured iodine can be retained for more than 7 days without any leaching, but readily released using methanol, when required. TIEPE-DABCO can be recycled for iodine capture several times without any loss of storage capacity. The results presented in this work demonstrate the potential of mechanochemical cocrystal engineering with halogen bonding as an approach to develop porous materials for iodine capture and sensing.     

Studies on viteline cells of monogenea. I. Morphology of viteline cells of Pricea multae

Water deprivation for 48 hr with its accompanying decrease in food intake significantly lowered the in vitro rate of hexobarbital metabolism by hepatic microsomes isolated from male rats. Pair-fed rats allowed water ad libitum had a significantly lower level of hexobarbital metabolism than those deprived of water. Rats starved for 24 hr with or without water also had levels of hexobarbital metabolism significantly lower than their controls; with those animals allowed water ad libitum, the level was significantly lower than for those deprived of water. In vivo hexobarbital "sleeping time" experiments were in general agreement with these results. The in vitro metabolism of aniline was increased in both male and female rats following 24 hr starvation and in female rats (but not males) the effect was greater when water was allowed than when deprived. The differences between hydrated and dehydrated animals were not attributable to reduction in concentration of microsomal protein or the water content of liver. It is concluded that water consumption accentuates the effect of food deprivation on hepatic microsomal metabolism.     

Prediction of Delta Ferrite Content and Effect of Welding Process Parameters in Claddings by FCAW

This article discusses the influence of welding process parameters on the content of delta ferrite in the claddings of AISI 317L, deposited onto IS: 2062 structural steel plate by the flux cored arc welding (FCAW) process. Measurement of delta ferrite within the cladding often gives important insight into the future mechanical and corrosion resistant behavior of the cladded structures. To predict and control the amount of residual ferrite, regression models were developed in terms of process parameters, using the data obtained from experiments. The experiments were conducted by using a central composite rotatable design of experiments. The study revealed that the cladding process parameters have influence over the formation of delta ferrite.     

Pickle-free chrome tanning using a polymeric synthetic tanning agent for cleaner leather processing

Stringent environmental regulations on the discharge of pollutants from various industries have prompted researchers to seek the development of eco-benign technologies. Conventional chrome tanning in leather processing discharges significant amounts of chromium, total dissolved solids and chlorides. Hence, tanners are looking for new product-process innovations towards low-waste and high exhaust chrome tanning. A polymeric syntan, which can enable pickle-free chrome tanning using commercial basic chromium sulphate, has been developed. A convenient process for tanning goatskins as well as cow hides has been designed. This method enhances the uptake of chromium to above 90%. Although the developed process is a highly reactive system, the tanned leathers are free from physical deposition of chromium as seen from microscopic analysis. The distribution of chromium in thicker cow sides is uniform and comparable to that of conventional tanned leathers even at reduced dosage. Further, the novel product-process helps to reduce the chemical oxygen demand (COD), total dissolved solids (TDS) and chlorides in the spent tan liquor by 50, 80 and 98% respectively. The product offers full, soft leathers having a shrinkage temperature comparable to that of conventional chrome tanned leathers. This integrated process provides reduction in chemicals, water, time and power consumption. Thus the novel product/process developed not only seeks advantages in reducing pollution loads but also seems to be techno-economically viable.     

Influence of friction stir processing parameters on surface modified 90Cu-10Ni composites

Friction Stir Processing (FSP) has emerged as a distinctive and pioneering solid state technique to produce surface composites. The objective of the present research is to produce reinforced 90/10 Copper–Nickel surface composites with different carbide-based ceramic particles through FSP and study the relationship of its dynamic parameters including tool rotational speed, tool traverse speed, and width of the groove over the surface behavior. Responses such as sliding wear, microhardness, and surface modified area in the friction stir processed region are modeled using polynomial, nonlinear, multiple regression based on the central composite design of experiment. Analysis of the developed models showed that the FSP parameters; traverse speed, rotational speed, and groove width have significant influence on both the sliding wear and microhardness of developed surface composite. And furthermore, tool rotational speed and tool traverse speed, simultaneously control dispersion of reinforcement in the surface. To validate the abovementioned noteworthy results and to study the microstructural aspects, selected specimens were carried over metallurgical analysis and the obtained results were put forward in detail in this paper.     

Unsupervised speaker segmentation with residual phase and MFCC features

This paper proposes an unsupervised method for improving the automatic speaker segmentation performance by combining the evidence from residual phase (RP) and mel frequency cepstral coefficients (MFCC). This method demonstrates the complementary nature of speaker specific information present in the residual phase in comparison with the information present in the conventional MFCC. Moreover this method presents an unsupervised speaker segmentation algorithm based on support vector machine (SVM). The experiments show that the combination of residual phase and MFCC helps to identify more robustly the transitions among speakers.     

Performance Assessment of Secondary Settling Tanks Using CFD Modeling

Amongst the principal separation processes used to treat effluents in the water industry is the sedimentation of solid particulates from the carrier fluid known as mixed liquor by the force of gravity. New York City DEP is in the process of upgrading its Upper East River water pollution control plants (WPCP??s) to incorporate biological nitrogen removal (BNR). The rectangular final settling tanks (FSTs) are a central link in the treatment process and often times a limiting factor in terms of the solids handling capacity especially when high throughput requirements need to be met. The objective of this study was to develop a 3D Computational Fluid Dynamics (CFD) model based on the exact geometry of the existing Gould II type FSTs in Battery ??E?? at the Wards Island WPCP and calibrate and validate it with in-situ data collected at the site. The goal of this study is to illustrate how the different modeling approaches applied on the physical phenomena that take place in the tank affect the outcome of a CFD model and its predictions. It is common for internal baffles to be added at the inlet and within the tank to handle high flow requirements such as wet weather storms. This model has been used as a tool to assess the internal behavior of such baffles and assess the clarifier??s performance based on different inlet baffle configurations.