Carbofuran degradation in soil profiles

Two soils, Puyallup fine sandy loam from Puyallup, WA, and Ellzey fine sand from Hastings, FL, each with a prior history of carbofuran exposure but with different pedological and climatological characteristics, were found to exhibit enhanced degradation toward carbofuran in surface and subsurface soil layers. The treated Puyallup and Ellzey soils exhibited higher mineralization rates for both the carbonyl and the aromatic ring of carbofuran when compared to untreated soils. Disappearance rates of [14C-URL (uniformly ring labeled)] carbofuran in the treated Ellzey soil was faster than in untreated soil, and also faster in surface soil than in subsurface soil. Initial degradation patterns in the treated Ellzey soil were also different from those in the untreated soil. The treated Ellzey soil degraded carbofuran mainly through biological hydrolysis, while untreated soil degraded carbofuran through both oxidative and hydrolytic processes.     

Microbial degradation of tetraethyl lead in soil monitored by microcalorimetry

Fos immunohistochemistry was used to stain neurons in the caudal diencephalon, midbrain and hindbrain driven by rewarding stimulation of the lateral hypothalamus (LH). Increases in Fos-like immunoreactivity were most pronounced ipsilateral to the site of stimulation and tended to be confined within discrete structures such as the posterior LH, arcuate nucleus, ventral tegmental area (VTA), central gray, dorsal raphé, pedunculopontine area (PPTg), parabrachial nucleus, and locus coeruleus. At least two of these structures, the VTA and PPTg, have been implicated in medial forebrain bundle self-stimulation.     

Enhanced degradation of polychlorinated biphenyls by directed evolution of biphenyl dioxygenase

Data characterizing is considered the first and main stage of the statistical analysis. Rather than characterizing each biomechanical signal through one or few global indicators, such as the mean or the root mean square, this paper suggests first to cut the scale into several fuzzy windows and to summarize the data within each window through an occurrence indicator. These indicators become the analysis variables. They can be analyzed through the multiple correspondence analysis, which shows the most discriminant variables, connections between them, empirical situation classes and correspondences between these classes and the most discriminant variables. An example is considered for arguing our point of view; it concerns characterizing and analysis of forces situated at the hand, foot and back level in a load lifting task.     

Lysosomal degradation on vesicular membrane surfaces. Enhanced glucosylceramide degradation by lysosomal anionic lipids and activators

According to a recent hypothesis (Sandhoff, K., and Kolter, T. (1996) Trends Cell Biol. 6, 98-103), glycolipids, which originate from the plasma membrane, are exposed to lysosomal degradation on the surface of intralysosomal vesicles. Taking the interaction of membrane-bound lipid substrates and lysosomal hydrolases as an experimental model, we studied the degradation of glucosylceramides with different acyl chain lengths by purified glucocerebrosidase in a detergent-free liposomal assay system. Our investigation focused on the stimulating effect induced by lysosomal components such as sphingolipid activator protein C (SAP-C or saposin C), anionic lysosomal lipids, bis(monoacylglycero)phosphate, and dolichol phosphate, as well as degradation products of lysosomal lipids, e.g. dolichols and free fatty acids. The size of the substrate-containing liposomal vesicles was varied in the study. Enzymatic hydrolysis of glucosylceramide carried by liposomes made of phosphatidylcholine and cholesterol was rather slow and only weakly accelerated by the addition of SAP-C. However, the incorporation of anionic lipids such as bis(monoacylglycero)phosphate, dolichol phosphate, and phosphatidylinositol into the substrate carrying liposomes stimulated glucosylceramide hydrolysis up to 30-fold. Dolichol was less effective. SAP-C activated glucosylceramide hydrolysis under a variety of experimental conditions and was especially effective for the increase of enzyme activity when anionic lipids were inserted into the liposomes. Glucosylceramides with short acyl chains were found to be degraded much faster than the natural substrates. Dilution experiments indicated that the added enzyme molecules associate at least partially with the membranes and act there. Surface plasmon resonance experiments demonstrated binding of SAP-C at concentrations up to 1 microM to liposomes. At higher concentrations (2.5 microM SAP-C), liposomal lipids were released from the liposome coated chip. A model for lysosomal glucosylceramide hydrolysis is discussed.     

Characterization of two novel propachlor degradation pathways in two species of soil bacteria

Propachlor (2-chloro-N-isopropylacetanilide) is an acetamide herbicide used in preemergence. In this study, we isolated and characterized a soil bacterium, Acinetobacter strain BEM2, that was able to utilize this herbicide as the sole and limiting carbon source. Identification of the intermediates of propachlor degradation by this strain and characterization of new metabolites in the degradation of propachlor by a previously reported strain of Pseudomonas (PEM1) support two different propachlor degradation pathways. Washed-cell suspensions of strain PEM1 with propachlor accumulated N-isopropylacetanilide, acetanilide, acetamide, and catechol. Pseudomonas strain PEM1 grew on propachlor with a generation time of 3.4 h and a Ks of 0.17 +/- 0.04 mM. Acinetobacter strain BEM2 grew on propachlor with a generation time of 3.1 h and a Ks of 0.3 +/- 0.07 mM. Incubations with strain BEM2 resulted in accumulation of N-isopropylacetanilide, N-isopropylaniline, isopropylamine, and catechol. Both degradative pathways were inducible, and the principal product of the carbon atoms in the propachlor ring was carbon dioxide. These results and biodegradation experiments with the identified metabolites indicate that metabolism of propachlor by Pseudomonas sp. strain PEM1 proceeds through a different pathway from metabolism by Acinetobacter sp. strain BEM2.     

Application of principal component analysis to evaluation of black soil degradation in Jilin

Principal Component Analysis (PCA) can simplify the structure of database by replacing multidimensional parameters with relatively less comprehensive variables in order to ensure the minimum lost in initial data.In this paper, eighteen black soil samples from different sites were tested and thirteen distinctive indexes were chosen to evaluate the degeneration of black soil.By using principal component analysis, variables of thirteen dimensions can be diminished to six unrelated principal indexes.Analysis shows that the soluble salt content, Fulvic acids (FA) and aggregation degree have a high weighing coefficient, indicating these three indexes are the major parts for the evaluation of black soil degradation.It also provides a new path to the degenerated black soil treatment in Northeast China.     

The degradation of [14C]molinate in soil under flooded and nonflooded conditions

The degradation of [14C]molinate in soil under flooded and nonflooded conditions was investigated. In laboratory studies, 50 percent of the applied molinate was lost in 3 weeks under moist soil conditions, while under flooded conditions, dissipation was reduced to 50 percent loss in 10 weeks. Analysis for molinate and its degradation products in the soil and flood water showed that under flooded conditions very little breakdown of molinate occurred, and volatilization was the primary mode of dissipation. However, under nonflooded conditions, hydroxylation of the azepine ring and further oxidation to the respective ketones occurs. Oxidation to form the sulfoxide, cleavage to yield the imine, and acetylation of the imine are also proposed. Other pathways appear to involve desethylation to produce a free thiocarbamic acid derivative followed by S-methylation as well as carboxylation of the S-ethyl group.     

Enhanced photocatalytic degradation of organic dyes from aqueous environment using neodymium-doped mesoporous layered double hydroxide

Neodymium-doped Zn–Al layered double hydroxide (Nd/Zn-Al LDH) with excellent photocatalytic activity was prepared by a one-step hydrothermal method. The morphology and physicochemical properties of as-synthesized photocatalysts were well analyzed by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL), UV-diffuse reflectance spectroscopy (UV-DRS), and Brunauer-Emmett-Teller (BET) surface analysis. Doping Nd³⁺ into Zn–Al LDH enhances the overall catalytic activity of the nanocomposite, like better electron–hole pair separation, increase in interplanar distance, fast electron transfer, and large surface area. The as-prepared nanocomposite shows excellent degradation of three different dyes under visible light irradiation. The degradation efficiency of these dyes follows the order of Congo red > rose Bengal > fast green. Furthermore, liquid chromatography-mass spectrometry (LC-MS) was employed to propose a possible photocatalytic degradation pathway for Congo Red and Rose Bengal dyes by Nd/Zn–Al LDH. With the help of radical trapping experiments, it is revealed that during the photoexcitation process, the primary reactive intermediates are hydroxyl radicals.     

A survey of high school psychology in Iowa.

Surveyed 116 teachers of high school psychology (PSY) in Iowa to determine their teaching activities, the characteristics of their courses, and their educational backgrounds. Most Ss taught one or more other courses in addition to PSY. 51% described their PSY courses as being a combination of PSY as an approach to understanding life and PSY as a science; 65% combined lecture and discussion teaching methods. Only 12% had majored in PSY in college, although 29% had taken 5–6 PSY courses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Tuberculosis in brood sows and pigs slaughtered in Iowa

Mycobacterium avium was isolated from 21 of 23 lymph nodes with lesions collected from 23 brood sows and from 17 lymph nodes with lesions of 17 pigs slaughtered at an abattoir in north central Iowa. Mycobacterium avium serotype 2 accounted for more than 65% of the isolations in sows and in pigs. Granulomas with acid-fast bacilli were found in 15 of 23 tissues from brood sows and in 13 of 17 lymph nodes from pigs. Similar microscopic lesions were observed in the sows and pigs.     

Enhanced photocatalytic degradation of 4-nitrophenol using polyacrylamide assisted Ce-doped YMnO3 nanoparticles

This research article mainly reports on the precise structural,optical,and photocatalytic properties of cerium(Ce)-substituted yttrium manganite(YMnO₃) nanoparticles synthesized by the polyacrylamide gel method.The characteristics of YMnO₃ were investigated by the substitution of Ce into the Y site at various molar percentages.The Raman and X-ray diffraction(XRD) analyses confirmed the pure phase of hexagonal YMnO₃,supported by the Rietveld refinement.The microst...     

Iowa record-linkage study: death rates in psychiatric patients

The Iowa record-linkage study was developed to investigate death rates in psychiatric patients, and involved computer matching of death certificates with a roster of patients. A list of all patients admitted to our hospital from 1972 through 1981 was obtained and after removing duplicate entries the list was pared to 5412 names. The record included multiple identifiers (e.g., name, gender, date-of-birth, hospital number). This information was then linked by computer with all Iowa death certificates for the same period; a total of 331 deaths were identified. Patients were assigned to a single psychiatric diagnostic category based on a computer program that reviewed each patient's clinical diagnoses and picked the one with the highest priority in a hierarchy we had created. Age and sex adjusted mortality tables were constructed, allowing us to compute expected numbers of deaths. Relative risk for premature death was greatest among women, and those under 20 years. Risk was associated with all psychiatric diagnoses and was significantly higher among patients of either gender with an organic mental disorder or schizophrenia; women with acute schizophrenia, depressive neuroses, alcoholism, drug abuse, and psychophysiological disorders; and men with neuroses. Death from natural causes, especially from heart disease, was significantly excessive among women, while death from accidents and suicides was excessive for both men and women. The overall SMR was 1.65 (P < 0.001). Most importantly, we found that the greatest excess of mortality occurred within the first 2 years following hospital discharge. Thus, we were able to demonstrate that risk of mortality in general, and of suicide specifically, differed according to age, gender, diagnosis, and portion of the follow-up. We have subsequently used this method to investigate specific risk factors associated with mortality in mood disorders, schizophrenia, and antisocial personality disorder. Findings from these studies are reported.     

Long-Term Field Performance of Cold In-Place Recycled Roads in Iowa

Cold in-place recycling (CIR) is one of the most effective methods to rehabilitate asphalt pavements. In fact, most CIR roads have performed well at low cost in Iowa since the first CIR road was constructed in 1986. However, some CIR roads have reached failures earlier than their expected design lives because there is no design standard for designing CIR roads with a limited amount of past performance information. Some of the most prominent problems seemed to have come from selecting CIR in areas where there are poor subgrades. Therefore, it is critical to collect CIR performance data along with falling weight deflectometer (FWD) data in order to develop performance models. The main purpose of this paper is to document that effort. The performance models were developed on the basis of historical data collected from CIR roads in Iowa. First, an inventory of CIR roads was created which includes construction information, subgrade and base characteristics, and traffic levels. In consideration of pavement age, level of traffic, and subgrade condition, 26 test sections were selected from the inventory of CIR roads and pavement surface distress surveys were conducted on these roads using an automated image collection system. Distress data were then compiled to compute pavement condition index (PCI) for each test section. FWD data were collected from each test section to determine its relative soil support condition. Finally, to determine their long-term performance, the PCI values were plotted against the pavement age for each group of pavements categorized by their soil support conditions and traffic levels. Overall, it can be concluded that the CIR roads in Iowa, all under traffic level of annual average daily traffic of 2,000, have performed very well and predicted to last up to 25 years before reaching the poor condition (PCI = 40) when the pavements are to be rehabilitated. The CIR roads with a good subgrade support, however, are predicted to last up to 35 years.     

Seroprevalence of antibodies against Toxoplasma gondii in free-ranging mammals in Iowa

Axenic cultures of the ammonia-oxidizing bacterium Nitrosomonas europaea were starved of ammonia (energy source) for up to 342 d. During this time the bacteria retained the ability to respond instantly to ammonia (1 mM) or hydroxylamine (0.1 mM) amendment by oxidizing it to nitrite without initial protein synthesis. In vivo, the ability to oxidize amended ammonia stayed almost constant during the starvation period, but a drop in the hydroxylamine oxidation rate (to 33%) was observed after 4 wk of starvation when exogenous hydroxylamine was supplied as sole energy source. In contrast, it has been shown that the level and in vitro activity of hydroxylamine oxidoreductase were not significantly affected during the starvation period. Only minor changes were detected between the protein patterns on one-dimensional SDS-PAGE of growing and starved cells. Thus, it is concluded that the activities of the energy-generating enzymes in N. europaea were not affected during long-term ammonia starvation.     

Enhanced rate of intramolecular electron transfer in an engineered purple CuA azurin

The recent expression of an azurin mutant where the blue type 1 copper site is replaced by the purple CuA site of Paracoccus denitrificans cytochrome c oxidase has yielded an optimal system for examining the unique electron mediation properties of the binuclear CuA center, because both type 1 and CuA centers are placed in the same location in the protein while all other structural elements remain the same. Long-range electron transfer is induced between the disulfide radical anion, produced pulse radiolytically, and the oxidized binuclear CuA center in the purple azurin mutant. The rate constant of this intramolecular process, kET = 650 +/- 60 s-1 at 298 K and pH 5.1, is almost 3-fold faster than for the same process in the wild-type single blue copper azurin from Pseudomonas aeruginosa (250 +/- 20 s-1), in spite of a smaller driving force (0.69 eV for purple CuA azurin vs. 0.76 eV for blue copper azurin). The reorganization energy of the CuA center is calculated to be 0.4 eV, which is only 50% of that found for the wild-type azurin. These results represent a direct comparison of electron transfer properties of the blue and purple CuA sites in the same protein framework and provide support for the notion that the binuclear purple CuA center is a more efficient electron transfer agent than the blue single copper center because reactivity of the former involves a lower reorganization energy.     

Enhanced Surface Cooling as an Alternative for Thermal Discharges

Excess heat is an unavoidable by-product of electricity generation from fossil and nuclear fuels. In most cases, excess heat is transferred to a cooling water stream and discharged to a local receiving water body, or processed through on-site cooling towers. In many cases existing discharges are potentially responsible for significant ecological impacts, and regulatory authorities are mandating the construction of cooling towers, often at significant expense. Most existing cooling water discharges are designed to reduce excess temperatures through rapid dilution. Enhanced surface cooling is an alternative approach which involves the development of a thin surface plume, while limiting mixing of the discharge with ambient waters. This process encourages rapid transfer of heat to the atmosphere while limiting impacts to sensitive benthic environments and most of the volume of the receiving water body. This discharge approach may be particularly effective for receiving water bodies which have limited natural flushing, such as enclosed bays, estuaries, reservoirs and some river environments. A preliminary case study of a thermal discharge into Mt. Hope Bay (Massachusetts/Rhode Island) is discussed.     

Damage Detection in Composite Plates by Using an Enhanced Time Reversal Method

A damage detection technique, which does not rely on any past baseline signals, is proposed to assess damage in composite plates by using an enhanced time reversal method. A time reversal concept of modern acoustics has been adapted to guided-wave propagation to improve the detectability of local defects in composite structures. In particular, wavelet-based signal processing techniques have been developed to enhance the time reversibility of Lamb waves in thin composite laminates. In the enhanced time reversal method, an input signal at an excitation point can be reconstructed if a response signal measured at another point is reemitted to the original excitation point after being reversed in a time domain. This time reversibility is based on linear reciprocity of elastic waves, and it is violated when nonlinearity is caused by a defect along a direct wave path. Examining the deviation of the reconstructed signal from the known initial input signal allows instantaneous identification of damage without requiring the baseline signal for comparison. The validity of the proposed method has been exemplified through experimental studies on a quasi-isotropic laminate with delamination.     

Enhanced ductility in an aluminum-4 Pct magnesium alloy at elevated temperature

A considerable enhancement of the tensile ductility in a commercial Al-4 pct Mg alloy is observed during deformation at elevated temperatures (up to 250°C) and slow strain rates. Total elongations of ∼175 pct at 250°C were obtained compared to 27 pct at ambient temperature. Much of this ductility was a result of large increases with temperature in the post uniform or diffuse necking strain. Measurements of strain rate sensitivity,m, as a function of strain, strain rate, and temperature showed thatm near fracture was linearly related to total elongation. The mechanisms controllingm in this Al-4 pct Mg alloy were dynamic strain aging at the lower temperature range and dynamic recovery at the higher temperatures.m was found to be a function of strain only when the relative fraction of dynamic recovery was greater than ∼35 pct. A comparison ofm as measured in pure aluminum and in the commercial Al-4 pct Mg alloy suggests that Mg additions can significantly increasem during dynamic recovery.