Influences of land use/cover on water quality in the upper and middle reaches of River Njoro, Kenya

Data from 10 sampling sites along the River Njoro are used to examine the contribution of nutrients from upstream land uses draining each of the sampling sites. The data also are used to assess whether both the proportion of land uses and the size of the subwatersheds account for the variability in water quality in the River Njoro watershed. Geographical Information System analysis was used to determine the spatial distribution of land‐cover types and subwatersheds contributing run‐off to the sampling sites in the River Njoro. Standard Digital Elevation Model‐based routines were used to establish the watershed area contributing run‐off to each sampling site. Water and sediment samples were collected for chemical analysis, and the nutrient levels were related to the upstream land‐use types and the size of the subwatersheds. The mid‐stream portion of the River Njoro (near Egerton University) accounts for the highest nutrient contributions. The percentage contribution is magnified by additions from industrial, human settlements and agricultural land uses around the University. There is a significant decrease in nutrient levels downstream, however, indicating natural purification as the river flows through an area of large‐scale farming with intense, well‐preserved riparian and in‐stream vegetation. Steep slopes of the land upstream of Egerton University enhance erosion and nutrient losses from those subwatersheds. Mixed small‐scale agricultural and bare lands contribute over 55% of the phosphorus load to the upper and mid‐reaches of the River Njoro. The size of the subwatershed accounts for about 53% of the variability in the soluble phosphorus in the river. The land‐use subwatershed proportions are important for characterizing and modelling water quality in the River Njoro watershed. Upland land uses are as important as near‐stream land uses. We suggest that conservation of intact riparian corridor along the river and its tributaries contributes significantly to natural purification processes and recovery of the ecological integrity of the River Njoro ecosystem.     

AHIMA (American Health Information Management Association) executives expand their role in electronic record issues. Interview by Carolyn Dunbar

Four of the top leaders in the American Health Information Management Association met with Computers in Healthcare, detailing their coalition-building efforts to make the computer-based patient record a reality. They reinforce their belief in the eventual reality of the CPR and its security, and call for sanctions and penalties for those who misappropriate or misuse patient records.     

Nonlinearity Measurements of High-Power Laser Detectors at NIST

We briefly explain the fundamentals of detector nonlinearity applicable to both electrical and optical nonlinearity measurements. We specifically discuss the attenuation method for optical nonlinearity measurement that the NIST system is based upon, and we review the possible sources of nonlinearity inherent to thermal detectors used with high-power lasers. We also describe, in detail, the NIST nonlinearity measurement system, in which detector responsivity can be measured at wavelengths of 1.06 µm and 10.6 µm, over a power range from 1 W to 1000 W. We present the data processing method used and show measurement results depicting both positive and negative nonlinear behavior. The expanded uncertainty of a typical NIST high-power laser detector calibration including nonlinearity characterization is about 1.3 %.     

Associations of postural knowledge and basic motor skill with dyspraxia in autism: Implication for abnormalities in distributed connectivity and motor learning.

Children with autism often have difficulty performing skilled movements. Praxis performance requires basic motor skill, knowledge of representations of the movement (mediated by parietal regions), and transcoding of these representations into movement plans (mediated by premotor circuits). The goals of this study were (a) to determine whether dyspraxia in autism is associated with impaired representational (“postural”) knowledge and (b) to examine the contributions of postural knowledge and basic motor skill to dyspraxia in autism. Thirty-seven children with autism spectrum disorder (ASD) and 50 typically developing (TD) children, ages 8–13, completed (a) an examination of basic motor skills, (b) a postural knowledge test assessing praxis discrimination, and (c) a praxis examination. Children with ASD showed worse basic motor skill and postural knowledge than did controls. The ASD group continued to show significantly poorer praxis than did controls after accounting for age, IQ, basic motor skill, and postural knowledge. Dyspraxia in autism appears to be associated with impaired formation of spatial representations, as well as transcoding and execution. Distributed abnormality across parietal, premotor, and motor circuitry, as well as anomalous connectivity, may be implicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Demographic Futures as a Guide to Planning: California's Latinos and the Compact City

Demographic futures are proposed as an empirical and normative guide for planning. Projections of demographic change help planners prepare future-oriented plans that are better targeted to the needs of a changing clientele. As an example, population changes in California highlight the growing importance of Latinos to the development of more compact cities. Demographic futures also entail normative interpretations of future scenarios as much as they do empirical relationships projected into the future. Several alternative stories are related of Latinos' future situation, each highlighting different value premises, problems, and conclusions. To effectively use demographic futures, planners must be conversant with both projected trends and competing interpretive stories.     

Measuring fig quality using near-infrared spectroscopy

Sorting of dried figs prior to inspection is labor-intensive and somewhat complex. We examined the potential of using near-infrared spectroscopy (NIRS) to automate sorting of dried figs. Calimyrna and Adriatic types were inspected by hand using established criteria. For both varieties, approximately 100 passable figs and 100 figs each for the infested, rotten, sour, and dirty defect categories were examined using NIRS and partial least-squares regression (PLS). Correct classifications for these varieties ranged from 83 to 100%. About twenty PLS factors were used to make the predictions. These results indicate that the use of NIRS to help automate inspection for dried fig processing is feasible. However, the large number of wavelengths needed for prediction, as indicated by PLS beta coefficients, indicates that implementing NIRS in fig sorting may require an instrument capable of reading numerous wavelengths rather than a more economical filter-based instrument.     

Mapping of a yeast G protein betagamma signaling interaction

The mating pathway of Saccharomyces cerevisiae is widely used as a model system for G protein-coupled receptor-mediated signal transduction. Following receptor activation by the binding of mating pheromones, G protein betagamma subunits transmit the signal to a MAP kinase cascade, which involves interaction of Gbeta (Ste4p) with the MAP kinase scaffold protein Ste5p. Here, we identify residues in Ste4p required for the interaction with Ste5p. These residues define a new signaling interface close to the Ste20p binding site within the Gbetagamma coiled-coil. Ste4p mutants defective in the Ste5p interaction interact efficiently with Gpa1p (Galpha) and Ste18p (Ggamma) but cannot function in signal transduction because cells expressing these mutants are sterile. Ste4 L65S is temperature-sensitive for its interaction with Ste5p, and also for signaling. We have identified a Ste5p mutant (L196A) that displays a synthetic interaction defect with Ste4 L65S, providing strong evidence that Ste4p and Ste5p interact directly in vivo through an interface that involves hydrophobic residues. The correlation between disruption of the Ste4p-Ste5p interaction and sterility confirms the importance of this interaction in signal transduction. Identification of the Gbetagamma coiled-coil in Ste5p binding may set a precedent for Gbetagamma-effector interactions in more complex organisms.     

Determination and analysis of antigenic epitopes of prostate specific antigen (PSA) and human glandular kallikrein 2 (hK2) using synthetic peptides and computer modeling

In comparison with pyeloplasty, endourologic procedures for the treatment of ureteropelvic junction obstruction offer good success rates with less morbidity and a shorter hospitalization; however, studies have found lower success rates and increased complications in patients with crossing vessels. Conventional diagnostic angiography and intravenous urography have both been used to identify crossing vessels at the UPJ; but, a reliable, less invasive, less costly, and simpler preoperative procedure to identify crossing vessels is needed. Helical CT with CT angiography is a promising noninvasive technique for the identification of crossing vessels at the ureteropelvic junction, which can be used for surgical planning of endourologic treatment of UPJ obstruction.     

The effects of anesthesia on the biodistribution of drugs in rats: a carboplatin study

PURPOSE: Anesthetics can alter the biodistribution profile of drugs and, consequently, the regional pharmacokinetics of antineoplastic drugs at the tumor site. The effect of coadministered anesthetics on the biodistribution profile of carboplatin was studied in rats. METHODS: Female Wistar rats were used to compare the effects of ketamine/xylazine, thiopental and pentobarbital on the biodistribution of 30 mg/kg radiolabelled 195mPt-carboplatin administered intravenously, with conscious rats as the control group. Blood and urine samples were collected between 5 and 120 min. RESULTS: The percentage values of the injected dose of platinum per ml (%ID/ml) in plasma at the final time-point were respectively, 0.557%, 0.156%, 0.115% and 0.086%, in pentobarbital-, ketamine/xylazine- and thiopental-injected rats, and in conscious animals. Following the same sequence of groups, the %ID/ml values of platinum in the cumulative urine were 0.001%, 0.619%, 0.184% and 0.118%, respectively. Urine output varied from very little in the pentobarbital group, to several milliliters in the other groups. CONCLUSIONS: There was an increase of almost 100-fold in total platinum uptake in the kidneys, cerebrum and cerebellum of rats receiving pentobarbital over the uptake in the control rats, whereas the biodistribution profile of the thiopental group had the least variance. These results demonstrate the importance of anesthetic selection in animal pharmacokinetic studies, as it influences the biodistribution and pharmacokinetic profile of the drug being studied.     

Effect of preservatives addition on the shelf-life extensions and quality of flat bread as determined by near-infrared spectroscopy and texture analysis

Many people do not have refrigeration or frozen storage to inhibit mould growth and keep the Arabic bread fresh for more than a few days. Therefore, shelf-life extension is necessary for this type of bread. The present study hypothesised that the addition of preservatives may be done in Arabic flat bread (AFB) to extend shelf-life. Thus, objectives of this study were to evaluate selected preservatives to inhibit mould growth and to employ physical techniques, to monitor bread aging. Three preservatives, fumaric acid (0.2%, F), sodium propionate (0.3%, P), and sodium propionate-fumaric acid mixture (PF) were used. Tensile tests, and near-infrared reflectance spectroscopy (NIRS) were used to monitor bread ageing. The addition of PF in the AFB formula significantly increased the time of tearing at 0 day. For all treatments, the NIRS results showed high R²-values between the actual storage days and NIRS predictions. The NIRS and texture analysis are valuable tools to detect the effect of the preservatives on AFB shelf-life and quality.