Participatory evaluation guides the development and selection of farmers' preferred rice varieties for salt- and flood-affected coastal deltas of South and Southeast Asia.

Rice is the staple food and provides livelihood for smallholder farmers in the coastal delta regions of South and Southeast Asia. However, its productivity is often low because of several abiotic stresses including high soil salinity and waterlogging during the wet (monsoon) season and high soil and water salinity during the dry season. Development and dissemination of suitable rice varieties tolerant of these multiple stresses encountered in coastal zones are of prime importance for increasing and stabilizing rice productivity, however adoption of new varieties has been slow in this region. Here we implemented participatory varietal selection (PVS) processes to identify and understand smallholder farmers' criteria for selection and adoption of new rice varieties in coastal zones. New breeding lines together with released rice varieties were evaluated in on-station and on-farm trials (researcher-managed) during the wet and dry seasons of 2008-2014 in the Indian Sundarbans region. Significant correlations between preferences of male and female farmers in most trials indicated that both groups have similar criteria for selection of rice varieties. However, farmers' preference criteria were different from researchers' criteria. Grain yield was important, but not the sole reason for variety selection by farmers. Several other factors also governed preferences and were strikingly different when compared across wet and dry seasons. For the wet season, farmers preferred tall (140-170 cm), long duration (160-170 d), lodging resistant and high yielding rice varieties because these traits are required in lowlands where water stagnates in the field for about four months (July to October). For the dry season, farmers' preferences were for high yielding, salt tolerant, early maturing (115-130 d) varieties with long slender grains and good quality for better market value. Pest and disease resistance was important in both seasons but did not rank high. When farmers ranked the two most preferred varieties, the ranking order was sometimes variable between locations and years, but when the top four varieties that consistently ranked high were considered, the variability was low. This indicates that at least 3-4 of the best-performing entries should be considered in succeeding multi-location and multi-year trials, thereby increasing the chances that the most stable varieties are selected. These findings will help improve breeding programs by providing information on critical traits. Selected varieties through PVS are also more likely to be adopted by farmers and will ensure higher and more stable productivity in the salt- and flood-affected coastal deltas of South and Southeast Asia.

Identification of mega-environments and rice genotypes for general and specific adaptation to saline and alkaline stresses in India.

In the present study, a total of 53 promising salt-tolerant genotypes were tested across 18 salt-affected diverse locations for three years. An attempt was made to identify ideal test locations and mega-environments using GGE biplot analysis. The CSSRI sodic environment was the most discriminating location in individual years as well as over the years and could be used to screen out unstable and salt-sensitive genotypes. Genotypes CSR36, CSR-2K-219, and CSR-2K-262 were found ideal across years. Overall, Genotypes CSR-2K-219, CSR-2K-262, and CSR-2K-242 were found superior and stable among all genotypes with higher mean yields. Different sets of genotypes emerged as winners in saline soils but not in sodic soils; however, Genotype CSR-2K-262 was the only genotype that was best under both saline and alkaline environments over the years. The lack of repeatable associations among locations and repeatable mega-environment groupings indicated the complexity of soil salinity. Hence, a multi-location and multi-year evaluation is indispensable for evaluating the test sites as well as identifying genotypes with consistently specific and wider adaptation to particular agro-climatic zones. The genotypes identified in the present study could be used for commercial cultivation across edaphically challenged areas for sustainable production.

TNF-alpha expression patterns as potential molecular biomarker for human skin cells exposed to vesicant chemical warfare agents: sulfur mustard (HD) and Lewisite (L).

Studies were conducted to examine the effect of two vesicant chemical warfare agents (VCWA), one of them an arsenical, on cytokine gene expression in normal human epidermal keratinocyte (NHEK) cells. We tested 2,2'-dichlorethylsulfide (sulfur mustard, military designation HD) and 2,chlorovinyldichloroarsine (Lewisite, military designation L), which have significant differences in their chemical, physical, and toxicological properties. Human tumor necrosis factor-alpha (hTNF-alpha) cytokine was detected by using the enzyme-linked immunosorbent assay, a protein multiplex immunoassay, Luminex100, and reverse transcription-polymerase chain reaction (RT-PCR). The messenger RNA expression of hTNF-alpha was determined to provide a semi-quantitative analysis. HD-stimulated NHEK induced secretion of hTNF-alpha in a dose-dependent manner. Dose response effect of Lewisite decreased hTNF-alpha levels. Time-response data indicated that the maximum response for HD occurred at 24 h with an associated cytotoxic concentration of 10(-4) mol/L. NHEK cells stimulated with 10(-4) mol/L HD for 24 h at 37 degrees C increased detectable levels of hTNF-alpha from 5 to 28 ng/ml at an index of cell viability between 85 to 93% as detected by Luminex100. Our results indicated that the increased levels of hTNF-alpha by HD are dependent on the primary cultures, cell densities, and chemical properties of the stimulation. Lewisite under the same conditions as HD caused a reduction of hTNF-alpha from control levels of 1.5 ng/ml to 0.3 ng/ml after stimulation (10(-4) mol/L), with an index of cell viability of reverse similar 34%. We analyzed the transcriptional of hTNF-alpha gene and found that HD (10(-6) to 10(-4) mol/L) activates hTNF-alpha gene in cultured NHEK and that L at 10(-6) to 10(-4) mol/L markedly reduces hTNF-alpha gene. We conclude that the pro-inflammatory mediator, hTNF-alpha, could be a potential biomarker for differentiating between exposure of HD or L.

The development of specialized brain systems in reading and oral-language.

Functional magnetic resonance imaging (fMRI) was used to examine differences between children (9-12 years) and adults (21-31 years) in the distribution of brain activation during word processing. Orthographic, phonologic, semantic and syntactic tasks were used in both the auditory and visual modalities. Our two principal results were consistent with the hypothesis that development is characterized by increasing specialization. Our first analysis compared activation in children versus adults separately for each modality. Adults showed more activation than children in the unimodal visual areas of middle temporal gyrus and fusiform gyrus for processing written word forms and in the unimodal auditory areas of superior temporal gyrus for processing spoken word forms. Children showed more activation than adults for written word forms in posterior heteromodal regions (Wernicke's area), presumably for the integration of orthographic and phonologic word forms. Our second analysis compared activation in the visual versus auditory modality separately for children and adults. Children showed primarily overlap of activation in brain regions for the visual and auditory tasks. Adults showed selective activation in the unimodal auditory areas of superior temporal gyrus when processing spoken word forms and selective activation in the unimodal visual areas of middle temporal gyrus and fusiform gyrus when processing written word forms.

Evolution of alachlor-induced nasal neoplasms in the Long-Evans rat.

The chloracetanilide herbicide alachlor (2-chloro-2',6-diethyl-N-(methoxymethyl)-acetanilide) induces nasal neoplasms in rats following chronic dietary exposure. The present study sought to identify the cellular origin and mechanisms of tumor induction and progression. Male Long-Evans rats were fed alachlor (0 or 126 mg/kg/day) beginning at 6 weeks of age. Following 1 month of alachlor ingestion, neither histological abnormalities nor enhanced cell division (assessed by BrdU incorporation) occurred in any region of the nasal cavity. Six months of alachlor exposure resulted in proliferation of basal and nonbasal cells in the olfactory mucosa while inducing nasal masses in 7 of 15 animals. Tumors ranged from dysplastic plaques to polypoid adenomas and originated in the olfactory regions of the nasal cavity. Neoplasms were associated with regions of respiratory metaplasia and were often covered with a low cuboidal, poorly ciliated epithelium. Tumor cells did not express characteristics of the olfactory mucosa, including olfactory marker protein (OMP, for neurons) and NMa (antibody recognizing cytochrome P450 [CYP] 2A3, found in Bowman's glands). Sites of plaque and tumor development coincided with regions of NMa immunoreactivity. These data suggest that local metabolism is important in alachlor-induced olfactory tumors and support the concept that metaplastic respiratory epithelial cells give rise to the observed neoplasms.

Quantitative buffy coat: a special adjunct for diagnosis of malaria.

Quantitative buffy coats (QBC) technique was compared with conventional blood film technique for the diagnosis of malaria in a tertiary care hospital. The QBC technique was found to be a rapid technique with a sensitivity of 83% and specificity of 94%. Malaria species identification was also possible. It was essentially very useful to detect parasites below < or = 100 parasites/ul of blood by QBC technique. However, quantification of parasitaemia could not be made using this technique. Many cases of carriers having very few gametocytes in their blood were also identified. It is therefore, concluded that the QBC technique, may be appropriate for screening populations for malaria and for detection of asymptomatic carriers to control further transmission of the disease in the community.

In-situ self-assembling protein polymer gel systems for administration, delivery, and release of drugs.

Sequential block copolymers consisting of tandem repetition of amino acids have been constructed and genetically produced based on the natural repeating structures of silk and elastin protein. Combinations of silklike and elastinlike amino acid sequence blocks in a high molecular weight protein polymer are used to confer properties similar to those observed with hard block and soft block segmented polyurethanes. A certain subset of these silk-elastinlike protein compositions, termed ProLastins, will undergo an irreversible solution to gel transition in physiological, aqueous solution. The transition occurs over time and can be controlled by temperature, solution conditions, and additives which either prevent or promote hydrogen bond-mediated chain crystallization. The process involves no covalent crosslinking. Characterization of the gelling properties of various ProLastin compositions and their ability to release compounds which are incorporated directly into the gels are presented.

Suppression of task-related saccades by electrical stimulation in the primate's frontal eye field.

Patients with frontal lobe damage have difficulty suppressing reflexive saccades to salient visual stimuli, indicating that frontal lobe neocortex helps to suppress saccades as well as to produce them. In the present study, a role for the frontal eye field (FEF) in suppressing saccades was demonstrated in macaque monkeys by application of intracortical microstimulation during the performance of a visually guided saccade task, a memory prosaccade task, and a memory antisaccade task. A train of low-intensity (20-50 microA) electrical pulses was applied simultaneously with the disappearance of a central fixation target, which was always the cue to initiate a saccade. Trials with and without stimulation were compared, and significantly longer saccade latencies on stimulation trials were considered evidence of suppression. Low-intensity stimulation suppressed task-related saccades at 30 of 77 sites tested. In many cases saccades were suppressed throughout the microstimulation period (usually 450 ms) and then executed shortly after the train ended. Memory-guided saccades were most dramatically suppressed and were often rendered hypometric, whereas visually guided saccades were less severely suppressed by stimulation. At 18 FEF sites, the suppression of saccades was the only observable effect of electrical stimulation. Contraversive saccades were usually more strongly suppressed than ipsiversive ones, and cells recorded at such purely suppressive sites commonly had either foveal receptive fields or postsaccadic responses. At 12 other FEF sites at which saccadic eye movements were elicited at low thresholds, task-related saccades whose vectors differed from that of the electrically elicited saccade were suppressed by electrical stimulation. Such suppression at saccade sites was observed even with currents below the threshold for eliciting saccades. Pure suppression sites tended to be located near or in the fundus, deeper in the anterior bank of the arcuate than elicited saccade sites. Stimulation in the prefrontal association cortex anterior to FEF did not suppress saccades, nor did stimulation in premotor cortex posterior to FEF. These findings indicate that the primate FEF can help orchestrate saccadic eye movements by suppressing inappropriate saccade vectors as well as by selecting, specifying, and triggering appropriate saccades. We hypothesize that saccades could be suppressed both through local FEF interactions and through FEF projections to subcortical regions involved in maintaining fixation.

Physician profiling: applications for the Robert Wood Johnson Profiling Project database.

An overview of the applications and limitations of the Center for Research in Ambulatory Health Care Administration (CRAHCA) Profiling Project database funded by The Robert Wood Johnson Foundation is presented. The Profiling Project collects data from 77 practices and links organizational, provider, and patient demographics to administrative data. The Project's database has the capacity (1) to profile physicians based on the Resource Based Relative Value Scale (RBRVS) relative value units as a measure of work and (2) to identify practice patterns as defined by procedures used by physicians with the same diagnosis. The Project will further explore variations between physicians and specialties based on systems of care, physician specialty, and patient differences. The comparative reports generated from these data provide comparisons on selected indicators for participating practices.

Primate frontal eye field activity during natural scanning eye movements.

1. As we scan an image, saccadic eye movements direct our vision to features that attract our attention. Although it is likely that the frontal eye field (FEF) cortex is an important component of the system generating those movements, most studies of FEF neuronal activity have relied upon visuomotor tasks where the experimental subjects are constrained to look from one spot of light to another. In this study, single-unit activity was recorded in the FEF while monkeys freely scanned a variety of projected images, and that activity was compared with activity evoked during conventional visuomotor tasks. 2. FEF neurons with visual activity in conventional tasks increased their activity during scanning when a portion of the image within their receptive field was targeted for the next saccade, but decreased their activity when a target was chosen outside of the receptive field. 3. FEF neurons with movement-related activity during conventional tasks were also active in association with saccades made during scanning. 4. Visual and movement activity were also studied by creating a task that approximated the conditions during the scanning paradigm (rescan task). This was done by superimposing a moveable spot of light onto the image that had been scanned, and rewarding the monkey for following the light as it recreated the original scan's spatial and temporal pattern of eye fixations. In contrast to the visual activity of neurons during the scanning paradigm, visual activity during the rescan task was unaffected by portions of the image within the cell's receptive field, but increased in response to the appearance of the target light.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of replacement of active site residue glutamine 231 on activity and allosteric properties of aspartate transcarbamoylase.

Since crystallographic studies on Escherichia coli aspartate transcarbamoylase (ATCase) indicate that Gln 231 is in the active site of the enzyme and participates in the binding of the substrate, aspartate, it seemed of interest to examine mutant enzymes in which Gln 231 was replaced by Asn or Ile. The two mutant forms containing amino acid substitutions were characterized by a combination of steady-state kinetics, hydrodynamic measurements, and equilibrium ligand binding techniques. Both mutant forms exhibited a dramatic reduction in the affinity of the protein for substrates and substrate analogues as well as a very large decrease in catalytic activity. Moreover, the amino acid substitutions introduced within the active site of the enzyme led to unusual allosteric properties in the mutant enzymes. Although the bisubstrate analogue N-(phosphonoacetyl)-L-aspartate promotes the characteristic global conformational change in the mutant forms that is observed with the wild-type enzyme, the combination of substrate and substrate analogue does not. Cooperativity with respect to substrate binding is largely reduced compared to wild-type ATCase. Also, the effector molecules ATP and CTP which bind to the regulatory chains have dramatic effects on the activity of the mutant enzymes containing replacements for Gln 231 in the catalytic chains. In stark contrast to the wild-type enzyme, in which effects of nucleotides are manifested primarily by changes in the K0.5 of the enzyme, ATP and CTP have large effects on the Vmax of the mutant enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Dental fear and anxiety in an older adult population.

A random sample of 580 people aged between 50 and 89 yr completed a questionnaire containing two measures of dental fear and anxiety. One of these was Corah's Dental Anxiety Scale (DAS) and the other a scale derived from the Structured Interview for Assessing Dental Fear (SIADF). The mean score on the DAS was 7.8, and 8.4% of subjects were classified as dentally anxious. There were no differences in mean DAS scores by sex but significant differences by age, with younger individuals having higher scores (P less than 0.0001). The edentulous had significantly higher scores than the dentate (P less than 0.001). Scores on the SIADF scale were higher among younger individuals (P less than 0.0001), the edentulous (P less than 0.01) and women (P less than 0.05). Older adults who were dentally anxious were less likely to report a regular source of dental care and a dental visit in the previous year and more likely to report having avoided or delayed dental treatment. Possible explanations of higher dental anxiety scores among younger persons and the edentulous are reviewed.

Self-reported fears (FSS-II) of subjects aged 50 years and over.

From studies of fears in children and adolescents, it was concluded that fears decrease with age and that girls show more fears than boys at the approach of adolescence. Community studies of adult fears as well as psychopathology have suggested a decrease in fears and phobic and anxiety symptoms with age. However, little is known of the distribution of fears in older adults. In view of this, the FSS-II was administered to a group of individuals aged 50 yr and over, as part of a larger epidemiological investigation of the oral health and treatment needs of older adults within Metropolitan Toronto. The results supported the hypothesis that the gender differences which ermerge at adolescence hold up into old age. The predicted age decrease in fearfulness was also supported.

Ontario dental assistants' job satisfaction: relationship to work stress and intention to change jobs.

Low job satisfaction has been linked to rapid turnover of dental assistants with resultant loss of productivity and reduced quality of patient care. Work dissatisfaction has also been linked to stress related diseases. The aim of this mailed survey of 1,000 Ontario certified dental assistants was to test a survey instrument developed in the United States and to relate satisfaction to work stress and to the intent to change jobs. Eighty-one per cent of eligible subjects responded. The satisfaction sub-scales of the survey instrument were found generally to have acceptable construct validity and to be reliable when applied to an Ontario population. However, some minor modifications were necessary. Although over 36 per cent said they were generally very satisfied with their work, the intent to change jobs was significantly related to areas of dissatisfaction concerning recognition for work done and opportunities for personal and professional growth. Stress was related to dissatisfaction with work-related fatigue, time pressure and nonpatient tasks. These findings have implications for dental practice management.

Work-related stress and its predictors among Canadian dental assistants.

This paper reports the results of a survey of 1000 certified dental assistants in Ontario, Canada. The aim was to obtain data on work-related stress, its sources and predictors. Of those responding to the survey, 38.8% said that their work was moderately stressful and 14.5% said it was very or extremely stressful. Approximately one-third had been bothered by stress at work on three or more days in the previous week. The main sources of stress were working under constant time pressures, running behind schedule and feeling undervalued by the dentist. Stepwise regression analysis revealed that the main predictors of work stress were not having a clear job description, working long hours, life stress while not at work and age. However, these variables explained less than 10% of the variance in job stress scores. Overall, 22.8% said it was very likely that they would seek work in another practice or seek work outside dentistry in the coming year. There was a significant association between work stress and job intentions; 43.0% of those reporting high levels of stress intended to change jobs compared to 8.9% of those who said that their job was not at all stressful (P less than 0.0001). These findings have implications for the way in which dental practice is organised and managed.

[Effect of lactose on the evaluation of the nutritive value of casein]. / Efecto de la lactosa en la evaluación del valor nutritivo de la caseína.

The biological evaluation of protein from dairy products such as normal and modified powdered milks where lactose is present, poses difficulties. It is known that when this sugar is contained in high concentrations, and due to its osmotic effect, it causes serious intestinal disorders in rats, thus obstructing the determination of the protein nutritional quality. In the study described herein, efforts were made to determine how lactose affects determination of the nutritional value of casein when this is evaluated by the Net Protein Utilization (NPU) procedure, and by the Relative Net Protein Ratio (RNPR) method. Thirty, and 21-day-old rats were fed with diets containing 10% and 8% of casein respectively, and lactose concentrations varying from 20% to 50%. All experiments lasted 10 days. The results demonstrated that casein's nutritional value did not differ significantly (p greater than 0.05) with lactose concentrations up to 40% in any of both methods, even though intestinal disorders were observed with more frequency and duration as lactose concentration increased.

Efecto de la lactosa en la evaluación del valor nutritivo de la caseina / Effect of lactose on the evaluation of the nutritive value of casein

La evaluación biológica de la calidad proteínica de productos lácteos como leches normales y modidicadas en polvo en los cuales interviene la lactosa, presenta dificultades. es sabido que por su efecto osmótico, cuando este azêúcar se encuentra en concentrciones considerables, produce srios trastornos intestinales en las ratas, lo qu dificulta ladeterminación de la calidad nutricional de la proteína de la dieta. En el trabajo objeto de esta comunicación, se trató de determinar cómo la lactosa incide sobre el valor nutritivo de la caseína,por el método de la Uazación Protenica Neta(UPN) y el método de la Relación Proteínica Neta Relativa(RPNR). En dichas experiencias se utizaron ratas de 30 y 21 días de edad, respectivamente. Las dietas empleadas contenían caseína al 10% y al 8% para la determinación de la UPN y de la RPNR, respectivamente, y cantidades crecientes de lactosa comprendidas entre 20% y 50%. En ambos métodos, esas dietas fueron suministradas a los animales durante 10 días. Los resultados obtenidos demostraron que, a pesar de los trastornos intestinales observados con mayor frecuencia y duración a medida que aumentaba la concentra de lactosa, el valor nutricional de la caseína no alcanzó una diferencia significativa, aún con concentraciones de 40% de lactosa en ninguno de los dos métodos(P>0.05).