Electrochemical decomposition of cyanides on tin dioxide electrodes in alkaline media

The electrochemical oxidation of cyanide in alkaline media was studied at different pH levels on SnO2 doped with Sb supported on titanium, at 25 degrees C, the electrooxidation of CN- at constant current follows a first-order rate law with a half life of t(1/2) = 35 min on SnO2-SbOx electrodes and t(1/2) = 69 min on SnO2-SbOx-RuO2 electrodes, in K2SO4(aq), pH 12, the reaction rate increases with the applied current and tends to reach a plateau when j > 20 mA cm(-2), In the pH range 10-13.5 the reaction rate diminishes as pH is increased owing to an increasing competition between CN- and OH- ions for the electrode surface. Addition of chloride to the solution does not alter the rate law but increases the reaction rate, A mechanism is proposed to explain the observed behaviour.

Electrochemical behavior of cobalt oxide coatings on cold-rolled steel in alkaline sodium sulfate

The electrochemical behavior of a coating of cobalt oxide on cold-rolled steel in alkaline sodium sulfate was Studied using the electrochemical techniques of open-circuit potential measurements and electrochemical impedance spectroscopy. The coating was prepared at different annealing temperatures ranging from 350 to 750 degreesC and characterized by SEM, EDX and XRD. Below 550 degreesC the composition of the coating was basically of Co3O4. At 750 degreesC CoO was formed and big cracks appeared on the film exposing an inner layer of iron oxides. Analysis of the EIS data is very difficult because of the complexity of the interface structure. It can be inferred that the charge transfer resistance of the coatings prepared at 350 and 450 C were higher than those for the coatings prepared at temperatures above 550 degreesC. (C) 2002 Published by Elsevier B.V. Ltd.

Magnetophotoluminescence study of GaAs/AlGaAs coupled double quantum wells with bimodal heterointerface roughness

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Anti-Angiogenic Effects of the Superantigen Staphylococcal Enterotoxin B and Bacillus Calmette-Guerin Immunotherapy for Nonmuscle Invasive Bladder Cancer

Purpose: We compared and characterized the effects of intravesical bacillus Calmette-Guerin and/or staphylococcal enterotoxin B for nonmuscle invasive bladder cancer.Materials and Methods: A total of 75 female Fisher 344 rats were anesthetized. of the rats 15 received 0.3 ml saline (control) and 60 received 1.5 mg/kg MNU (N-methyl-n-nitrosourea) intravesically every other week for 6 weeks. The rats were divided into 5 groups. The MNU and control groups received 0.3 ml saline. The bacillus Calmette-Guerin group received 10(6) cfu bacillus Calmette-Guerin. The staphylococcal enterotoxin B group received 10 mu g/ml staphylococcal enterotoxin B. The bacillus Calmette-Guerin plus staphylococcal enterotoxin B group received the 2 treatments simultaneously. Each group was treated intravesically for 6 weeks. At 15 weeks all bladders were collected for histopathological and immunological evaluation, and Western blot.Results: Papillary carcinoma (pTa) and high grade intraepithelial neoplasia (carcinoma in situ) were more common in the MNU group. Papillary hyperplasia was more common in the bacillus Calmette-Guerin and enterotoxin groups. Flat hyperplasia was more common in the bacillus Calmette-Guerin plus enterotoxin group. No significant toxicity was observed. The apoptosis and cellular proliferation indexes decreased in the bacillus Calmette-Guerin, enterotoxin and bacillus Calmette-Guerin plus enterotoxin groups compared to the MNU group. Intensified vascular endothelial growth factor, matrix metalloproteinase-9, Ki-67 and insulin-like growth factor receptor-1 immunoreactivity was verified in the MNU group, moderate in the bacillus Calmette-Guerin and enterotoxin groups, and weak in the bacillus Calmette-Guerin plus enterotoxin and control groups. In contrast, intense endostatin immunoreactivity was verified in the control and bacillus Calmette-Guerin plus enterotoxin groups.Conclusions: Bacillus Calmette-Guerin and staphylococcal enterotoxin B showed similar anti-angiogenic effects. Bacillus Calmette-Guerin plus enterotoxin treatment had additional activity compared to that of monotherapy. It was more effective in restoring apoptosis and balancing cellular proliferation, and it correlated with increased endostatin, and decreased vascular endothelial growth factor, matrix metalloproteinase-9, Ki-67 and insulin-like growth factor receptor-1 reactivity.

Nutritional status and functional capacity of hospitalized elderly

Background: The nutritional status of the aging individual results from a complex interaction between personal and environmental factors. A disease influences and is influenced by the nutritional status and the functional capacity of the individual. We asses the relationship between nutritional status and indicators of functional capacity among recently hospitalized elderly in a general hospital.Methods: A cross-sectional study was done with 240 elderly (women, n = 127 and men, n = 113) hospitalized in a hospital that provides care for the public and private healthcare systems. The nutritional status was classified by the MNA (Mini Nutritional Assessment) into: malnourished, risk of malnutrition and without malnutrition (adequate). The functional autonomy indicators were obtained by the self-reported Instrumental Activity of Daily Living (IADL) and Activity of Daily Living (ADL) questionnaire. The chi-square test was used to compare the proportions and the level of significance was 5%.Results: Among the assessed elderly, 33.8% were classified as adequate regarding nutritional status; 37.1% were classified as being at risk of malnutrition and 29.1% were classified as malnourished. All the IADL and ADL variables assessed were significantly more deteriorated among the malnourished individuals. Among the ADL variables, eating partial (42.9%) or complete (12.9%) dependence was found in more than half of the malnourished elderly, in 13.4% of those at risk of malnutrition and in 2.5% of those without malnutrition.Conclusion: There is an interrelationship between the nutritional status of the elderly and reduced functional capacity.

Bacillus thuringiensis development from 1971 to 1996: Cases of a research group in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Occurrence, distribution, and relative incidence of five viruses infecting cucurbits in the state of Sao Paulo, Brazil

Cucurbits species grown in 38 of 40 agricultural regions in the state of Sao Paulo, Brazil, were surveyed for the relative incidence of Cucumber mosaic virus (CMV), Papaya ringspot virus-type W (PRSV-W), Watermelon mosaic virus-2 (WMV-2), Zucchini lethal chlorosis virus (ZLCV), and Zucchini yellow mosaic virus (ZYMV) during May 1997 and June 1999. Samples from 621 plants, representing eight cultivated species, six wild species, and one commercial hybrid (Cucurbita moschata x C. maxima), were analyzed by plate trapped antigen enzyme-linked immunosorbent assay (PTA-ELISA). PRSV-W and ZYMV were the most frequently found viruses, accounting for 49.1 and 24.8%, respectively, of 605 samples tested. ZLCV, CMV, and WMV-2 were detected in 7.8, 6.0, and 4.5% of 612, 497, and 423 samples tested, respectively. Double infection was found in 97 samples, and triple infection was found in 10 samples. Quadruple infection was detected in one C. pepo sample. Plants that were symptomatic but negative by PTA-ELISA might be due to abiotic agents, infection by virus for which antiserum was not available, such as Squash mosaic virus, or infection with an as yet uncharacterized virus.

Determination of Cu, Ni and Pb in Aqueous Medium by FAAS after Pre-Concentration on 2-Aminothiazole Modified Silica Gel

This work describes the synthesis and characterization of 2-aminothiazole modified silica gel (SiAT), and the results of a study of the adsorption and pre-concentration (in batch and using a flow-injection system coupled to an absorption atomic spectrometer) of Cu(II), Ni(II) and Pb(II) in aqueous medium. The adsorption capacities for each metal ions in mmol g -1 were: Cu(II)= 1.18, Ni(II)= 1.15 and Pb(II)= 1.10. The results obtained in the flow experiments showed a recovery of practically 100% of the metal ions adsorbed in a mini-column packed with 100 mg of SiAT, using 100 μL of 2.0 mol L -1 HCl solution as eluent. The sorption-desorption of the metal ions made possible the application of a flow-injection system for the pre-concentration and quantification by FAAS of metal ions at trace level in natural water samples digested and not digest by an oxidizing UV photolysis.

Potencial cognitivo P300 em indivíduos com diabetes mellitus

Diabetes Mellitus may lead to alterations in the eyes, kidneys, cranial nerves, peripheral nerves, ears etc. The cognitive function, also, seems to be compromised in subjects presented with Diabetes Mellitus, since the cortical and subcortical structures responsible for this function are hindered in some insulin-dependent patients. The cognitive potential P300 has been used as an objective procedure to assess cerebral cognitive functions. Objective: Analyze the sensitivity of P300 cognitive potential for the detection of alterations on the auditory cortex secondary to Diabetes Mellitus. Study design: transversal cohort. Material and Method: Sixteen diabetic subjects of both genders aged 7 to 71 years, and seventeen non-diabetic individuals at the same age range participated in this study, the evaluation procedures were pure tone audiometry (PTA) and P300 cognitive potential. Glycemia of the group presented with Diabetes was assessed prior to applying the P300. Results: No statistically significant difference was shown for the PTA results. A statically significant difference was observed between groups when analyzing the latency of the P300 component measured in Fz. there was a correlation between glycemia and the latency and amplitude of P300. Conclusion: The investigation of the cognitive potential of P300 is an important procedure for the prevention and early diagnosis of neurological changes in individuals presented with Diabetes Mellitus.

Advances in prodrug design

The background of prodrug design is presented herein as the basis for introducing new and advanced latent systems, taking into account mainly the versatility of polymers and other macromolecules as carriers. PDEPT (Polymer-Directed Enzyme Prodrug Therapy); PELT (Polymer-Enzyme Liposome Therapy); CDS (Chemical Delivery System); ADEPT(Antibody-Directed Enzyme Prodrug Therapy); GDEPT/VDEPT (Gene-Directed Enzyme Prodrug Therapy/Virus-Directed Enzyme Prodrug Therapy); ODDS (Osteotropic Drug Delivery System) and LEAPT (Lectin-directed enzyme-activated prodrug therapy) are briefly described and some examples are given. © 2005 Bentham Science Publishers Ltd.

Depression severity levels and cognitive functions in institutionalized elderly patients

Depression is a highly prevalent illness among institutionalized aged and assumes peculiar characteristics such as the risk for progressing to dementia. The aims of this study was to assess the cognitive functions of institutionalized elderly with clinical diagnosis of depression and compare the severity of depressive symptoms with cognitive performance. From 120 residents at a nursing home in Rio Claro, Brazil, we study 23 individuals (mean age: 74.3 years; mean schooling: 4.0 years) with diagnosis of depression. At first, a clinical diagnosis of depression and measurement of its symptoms using the Geriatric Depression Scale were performed. The patient then underwent a neuropsychological assessment based on the following tests: Mini-Mental Examination, Verbal Fluency, Visual Perception, Immediate Memory, Recent Memory, Recognition, Clock Drawing Test. The patients were divided into two groups: those with less severe depression symptoms (Group 1: N=9) and more severe symptoms (Group 2: N=14). The significant difference between symptom severity of the two groups was p=0.0001. Patients with more severe symptoms revealed a slightly inferior cognitive performance in most of the tests when compared to those with less severe symptoms (p>0.05). In relation to Verbal Fluency, patients with more severe depression symptoms presented a significantly inferior cognitive performance when compared to those with less severe symptoms (p=0.0082). Verbal Fluency revealed to be a more sensitive test for measuring early cognitive alterations in institutionalized aged with depression, and appears to be a useful resource in monitoring the cognitive functions of patients faced with the risk of dementia. © Copyright Moreira Jr. Editora.

Resistência à compressão do concreto autoadensável: Influência da atividade pozolânica do calcário e do basalto

This research studies the influence of the pozzolanic activity of the calcareous and basalt in the resistence behavior of the compressive strength of high performance self-compacting concrete (HPSCC). The selected aditives are the calcareous filler and basalt filler, for they are industrial residues helping that way the sustainable development. The paste of this concrete type is constituted of cement, silica fume, calcareous filler or basalt filler, water and superplasticizer additive. In this research the relationships water/cement are fixed in 0,40 kg/kg, silica fume/cement of 0,10 kg/kg and the relationships filler/cement and superplasticizer/cement are determined through of Marsh́s cone and mini-slump tests. The granular skeleton is gotten from a composition between quartzous sand and brita of basalt that presents the lesser index of emptinesses. The results show that the HPSCC with the addition of calcareous filler has greater compressive strength than what the HPSCC with addition of basalt filler in the ages of 7, 28 and 63 days. It is explained by the fact that the calcareous filler presents greater index of pozzolanic activity than the basalt filler. Besides that the relation water/fine for the HPSCC with calcareous filler is 0,27 l/kg whereas the HPSCC with basalt filler is of 0,29 l/kg.

Early impairment of cognitive functions in Parkinson's disease

Background: Impairment in non-motor functions such as disturbances of some executive functions are also common events in Parkinson's disease patients. Objective: To verify the performance of Parkinson's disease patients in activities requiring visuoconstructive and visuospatial skills. Method: Thirty elderly patients with mild or moderate stages of Parkinson's disease were studied. The assessment of the clinical condition was based on the unified Parkinson's disease rating scale (56.28; SD=33.48), Hoehn and Yahr (2.2; SD=0.83), Schwab and England (78.93%), clock drawing test (7.36; SD=2.51), and mini-mental state examination (26.48; SD=10.11). Pearson's correlation and stepwise multiple regression were used for statistical analyses. Results: The patients presented deterioration in visuospatial and visuoconstructive skills. Conclusion: The clock drawing test proved to be a useful predictive tool for identifying early cognitive impairment in these individuals.

O uso da serragem no processo de minicompostagem

In this work used four cylindrical PVC (polyvinyl chloride) mini compost bins, they all had the same size and were identical, with 40 cm diameter and 75 cm length, they also were opened on both sides. Each mini compost bean received 35,5 kg of solid organic wastes, which were previously crushed and 6 kg of sawdust. It was evaluated during the composting process the C/N analyses, temperature measurement, humidity and pH. Results showed that the use of sawdust as a source of high carbon inputs on the mini compost beans and using low quantities of organic solid wastes reached temperatures as high as 65° C, keeping on the thermophilic phase for almost 6 days. After 18 days the environmental temperature was reached, the organic wastes were then laid to reach full maturity for 55 more days. The C/N ratio was initially around 30/1 and after 73 days it was around 12/1.

Caracterização e análise do estado mental e funcional de idosos institucionalizados em instituições públicas de longa permanência

Background: This study had as objective to characterize the institutionalized elderly residents in three long-term care facilities, about their functional capacity and mental state, and to evaluate if there is a correlation between both. Methods: To do so, three instruments were used: an identification form, the Mini-Mental State Examination (MMSE) and Barthel's Index. For statistical analysis the Person's Correlation and ANOVA Test were used. Results: The population studied consisted of 115 elders with ages between 62 and 104 years old, 40.66% females and 59.13% males. 49.56% are literate and 50.43% illiterate. Regarding the marital status, singles (46.65%) and widows (21.8%) were predominant. About the mental and functional state, there was a high rate of elders showing cognitive decline (76.72%) and functionally independent (75.65%). Conclusions: According to the results, one can notice that there is a mild degree of correlation between the Barthel's Index and MMSE (r = 0.441; p < 0.000), and the variables of gender and age are not influenced in the results of these instruments. There is a significant statistical relation (p < 0.0001) between education and mental and/or functional state of the individual.