Biodegradation of chlorpyrifos by either single or combined cultures of some soilborne plant pathogenic fungi

Biodegradation of chlorpyrifos was studied in liquid culture media amended with either single or combined eight different plant pathogenic fungi isolated from the continuous cropping wheat fields. The average recovery of chlorpyrifos from the liquid media was found to be 86.1%. The detection limit of chlorpyrifos by the analytical method used was 19 ppb. Data showed that the growth of mixed fungi at concentrations up to 200 ppm of chlorpyrifos was higher than in the control treatment. Chlorpyrifos concentrations declined in the medium of combined fungi more than it did in the medium of any single fungus with increase in the incubation period. The amount of chlorpyrifos recovered was 79.8 ppm (39.9%) in the combined fungal cultures after 21 days. However, those recovered from the media of Fusarium graminearum, F. oxysporum, Rhizoctonia solani, Cladosporium cladosporiodes, Cephalosporium sp., Trichoderma viridi, Alternaria alternata, and Cladorrhinum brunnescens, ranged from 48.0 to 74.8%. The half-life value (T1/2) for chlorpyrifos was 15.8 day in the medium amended with mixed fungi. However, for the single cultures it ranged from 19.3 to 33.0 day.     

Analyzing heterogeneity in conjoint estimates of residential preferences

Conjoint estimates of residential preferencesare typically based on aggregate responses. Forreasons of segmentation or to differentiatebetween non-significant housing attributes andattributes that are characterized byconflicting preferences, further analysis isrequired. In this paper, the heterogeneity inthe conjoint estimates of residentialpreferences of families is analyzed. It isexamined how the estimated part-worth utilitiesof the housing attributes are related to thesocio-economic variables and current housingattributes by applying regression analysis.Although the explained variance was rather low,suggesting that residential preferences offamilies are highly idiosyncratic, therelationships that were significant could beinterpreted well.     

Physicochemical Characterization of Polymer-Stabilized Coacervate Protocells

The bottom-up construction of cell mimics has produced a range of membrane-bound protocells that have been endowed with functionality and biochemical processes reminiscent of living systems. The contents of these compartments, however, experience semidilute conditions, whereas macromolecules in the cytosol exist in protein-rich, crowded environments that affect their physicochemical properties, such as diffusion and catalytic activity. Recently, complex coacervates have emerged as attractive protocellular models because their condensed interiors would be expected to mimic this crowding better. Here we explore some relevant physicochemical properties of a recently developed polymer-stabilized coacervate system, such as the diffusion of macromolecules in the condensed coacervate phase, relative to in dilute solutions, the buffering capacity of the core, the molecular organization of the polymer membrane, the permeability characteristics of this membrane towards a wide range of compounds, and the behavior of a simple enzymatic reaction. In addition, either the coacervate charge or the cargo charge is engineered to allow the selective loading of protein cargo into the coacervate protocells. Our in-depth characterization has revealed that these polymer-stabilized coacervate protocells have many desirable properties, thus making them attractive candidates for the investigation of biochemical processes in stable, controlled, tunable, and increasingly cell-like environments.     

Fretting wear behaviour of hypereutectic P/M Al–Si in oil environment

The fretting wear behaviour of forged hypereutectic P/M Al–Si in contact with hardened steel and Cu–Sn–Pb bearing material is investigated. Fretting tests are performed with a view to the movement in the contact between the small end of the connecting rod and the piston pin in a car engine. Therefore, the tests are carried out under engine oil lubrication at temperatures up to 150°C. The behaviour of the Al alloy is compared to that of steel, the current connecting rod material. Some tests under non-lubricated conditions are also performed. The correlation between the friction coefficient, the wear volume and the microscopic wear mechanisms is discussed. After the running-in wear, a stable wear condition is reached for the Al–Si/steel contact.     

Denitrification with methanol: Fundamental study of the growth and denitrification capacity of Hyphomicrobium sp

Hyphomicrobrium spp was found as dominant organism in a two-sludge nitrifying-denitrifying wastewater treatment system with methanol as external carbon source. The optimal pH for growth was found to be 8.3 and the organism seemed to be rather temperature sensitive (Q₁₀ = 3.3). The denitrification rate was expressed as a function of pH and temperature since it was almost independent on the concentrations of methanol and nitrate-nitrogen. Identical growth rates are found when using either nitrate- or nitrite-nitrogen; the nitrite consumption rate, however, is twice the nitrate reduction rate. Nitrate to nitrite reduction is the rate limiting step in denitrification reaction and some inhibition by high concentrations of nitrite on the nitrate reduction is measured. The methanol/nitrate-N ratio is 2.55 and increasing to 3.5 at extreme pH values. The endogenous denitrification rate is only 10% of the normal denitrification rate measured.     

Peritoneal cellular immunity and endometriosis

PROBLEM: An immunologic basis has long been considered to be very important in the pathogenesis of endometriosis. Interactions of the peritoneal cells, which comprise macrophages, B cells, T cells, natural killer (NK) cells, and retrograde endometrial cells, are critical, but remain controversial, for exploring the pathogenesis of endometriosis. METHOD OF STUDY: Accumulated data from the literature were reviewed, and our data were analyzed. RESULTS: The data show that peritoneal macrophages are activated by the recurrent reflux of menstrual shedding. Humoral and local endometrial autoantibodies are detected in patients with endometriosis, but B cells are not quantitatively increased. There is decreased NK cell activity in the peritoneal cavity and peripheral blood, and this decreased activity may be related to the failure to clear out the ectopic endometrial tissue. Peritoneal T cells are predominant by Th1 inflammatory cells, and these cells are impaired because of a decrease in activation (especially HLA-DR+CD4+CD3+ population) and in the production of interleukin-2. Inflammatory cytokines such as interleukin-1, interleukin-6, and tumor necrosis factor-alpha are elevated in the peritoneal fluid of women with endometriosis. CONCLUSIONS: The peritoneal NK and T lymphocytes are suppressed in women with endometriosis, but whether these immunologic deviations are the cause or the result of endometriosis is still unclear. Further studies are required to determine what role immunologic factors play in the pathophysiology of endometriosis.     

The sterilization effect of formaldehyde fumigating on the catheter place vertically

The aim of this paper is to investigate the effect of formaldehyde fumigating on the sterilization of catheters with different diameters and placed in different positions. The lumen of cleaned catheters with different diameters was filled with a solution of live bacilli coil. The catheters were then dried by a drier and divided into 3 groups for formaldehyde fumigating sterilization. A segment of 5 cm of the middle section of the sterilized catheters was cut and incubated at 36 degrees C for 48 h with bouillon medium. For those segments with positive culture, bacteriologic identification was done. RESULTS: Group A, U = 6.85 and P < 0.01; Group B, chi 2 = 8 and P < 0.01; Group C, chi 2 = 13, P < 0.01. CONCLUSIONS: in the same conditions, fumigating in vertical direction is better than fumigation in horizontal direction and save time; in the same conditions, the positive culture rate is inversely related to the diameter of the catheters; for catheter with a diameter greater than 0.75 cm, fumigating vertically for 2 h is enough to obtain satisfactory sterilization effects.     

Automated sampling and analysis in research product synthesis

The information obtained about relevant reaction parameters can be greatly increased by monitoring concentration changes during a reaction. To achieve this goal, a fully automated system was designed which handles both sampling and analysis. The sampling system takes samples at predefined intervals, and also performs a number of tasks such as dilution, neutralization, filtration and analysis.The examples show the universal applicability of the device regarding to solvents, reaction media and reaction type. It is also demonstrated that the information, included in the concentration profiles, greatly increases our knowledge about the reaction. This increase in information, in conjunction with other data,for example calorimetry, could be used for reaction simulation software.     

A novel cytosolic regulator, Pianissimo, is required for chemoattractant receptor and G protein-mediated activation of the 12 transmembrane domain adenylyl cyclase in Dictyostelium

Genetic analysis was applied to identify novel genes involved in G protein-linked pathways controlling development. Using restriction enzyme-mediated integration (REMI), we have identified a new gene, Pianissimo (PiaA), involved in cAMP signaling in Dictyostelium discoideum. PiaA encodes a 130-kD cytosolic protein required for chemoattractant receptor and G protein-mediated activation of the 12 transmembrane domain adenylyl cyclase. In piaA- null mutants, neither chemoattractant stimulation of intact cells nor GTPgammaS treatment of lysates activates the enzyme; constitutive expression of PiaA reverses these defects. Cytosols of wild-type cells that contain Pia protein reconstitute the GTPgammaS stimulation of adenylyl cyclase activity in piaA- lysates, indicating that Pia is directly involved in the activation. Pia and CRAC, a previously identified cytosolic regulator, are both essential for activation of the enzyme as lysates of crac- piaA- double mutants require both proteins for reconstitution. Homologs of PiaA are found in Saccharomyces cerevisiae and Schizosaccaromyces pombe; disruption of the S. cerevisiae homolog results in lethality. We propose that homologs of Pia and similar modes of regulation of these ubiquitous G protein-linked pathways are likely to exist in higher eukaryotes.