991 resultados para 1ST HYPERPOLARIZABILITY
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Wild-caught larvae, attributed to the lobster shrimp Arius serratus, consisting of two zoeal stages and a decapodid (megalopa), are described in detail. Parentage of larvae was ascertained based on geographic distribution of axiideans and gebiideans (= former thalassinideans) within the study area and close morphological resemblance to other congeneric larval stages. Larvae of A. serratus represent the first described 'thalassinidean' larvae from Canadian Atlantic waters and the first for Axiidae within the northwest Atlantic. Among axiidean larvae, those of A. serratus most closely resemble larvae of A. stirhynchus from the eastern Atlantic. Distinct features include the spination of the pleon that set A. serratus zoeae apart from those of most other 'thalassinideans' but that, in combination with a telson very similar to Homarus americanus, contributes to the general resemblance of A. serratus larvae to those of the American lobster. The primary distinction between these taxa is the presence of a chela on the third pereiopod in the latter that is not present in the former. In view of these appendages being prone to loss or damage, other characters that separate these taxa are listed and discussed. Given the uncertain status of some taxa within Axiidae and limited detailed information of larvae with certain parentage, difficulties in delineating the family based on larvae persist, as they do for cladistic analyses using adult morphology and molecular approaches.
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We examine the representation of judgements of stochastic independence in probabilistic logics. We focus on a relational logic where (i) judgements of stochastic independence are encoded by directed acyclic graphs, and (ii) probabilistic assessments are flexible in the sense that they are not required to specify a single probability measure. We discuss issues of knowledge representation and inference that arise from our particular combination of graphs, stochastic independence, logical formulas and probabilistic assessments. (C) 2007 Elsevier B.V. All rights reserved.
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The practicability of estimating directional wave spectra based on a vessel`s 1st order response has been recently addressed by several researchers. Different alternatives regarding statistical inference methods and possible drawbacks that could arise from their application have been extensively discussed, with an apparent preference for estimations based on Bayesian inference algorithms. Most of the results on this matter, however, rely exclusively on numerical simulations or at best on few and sparse full-scale measurements, comprising a questionable basis for validation purposes. This paper discusses several issues that have recently been debated regarding the advantages of Bayesian inference and different alternatives for its implementation. Among those are the definition of the best set of input motions, the number of parameters required for guaranteeing smoothness of the spectrum in frequency and direction and how to determine their optimum values. These subjects are addressed in the light of an extensive experimental campaign performed with a small-scale model of an FPSO platform (VLCC hull), which was conducted in an ocean basin in Brazil. Tests involved long and short crested seas with variable levels of directional spreading and also bimodal conditions. The calibration spectra measured in the tank by means of an array of wave probes configured the paradigm for estimations. Results showed that a wide range of sea conditions could be estimated with good precision, even those with somewhat low peak periods. Some possible drawbacks that have been pointed out in previous works concerning the viability of employing large vessels for such a task are then refuted. Also, it is shown that a second parameter for smoothing the spectrum in frequency may indeed increase the accuracy in some situations, although the criterion usually proposed for estimating the optimum values (ABIC) demands large computational effort and does not seem adequate for practical on-board systems, which require expeditious estimations. (C) 2009 Elsevier Ltd. All rights reserved.
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Predatory behaviour and reproductive output of the ladybird beetle Stethorus tridens Gordon as function of the tomato red spider mite (TRSM), Tetranychus evansi Baker & Pritchard, densities was investigated in the laboratory. Adult female of S. tridens were isolated in cylindrical plastic arenas, containing a leaf disc of Solanum americanum Mill. with 5, 20, 40, 60, 80 or 100 T. evansi nymphs. The number of prey consumed and eggs laid were evaluated daily for ten consecutive days, starting at the oviposition. Oviposition of S. tridens was positively correlated with prey consumption and lower threshold prey consumption for S. tridens laying eggs was 16.3 mites per day. The instantaneous rate of attack (ca. discovery area) and the handling time were 0.0062 h(-1) and 0.83 h, and 0.00254 h(-1) and 0.78 h, respectively, for predators at the 1st- and 10th-oviposition day. The predator exhibited a type II functional response at 1st- and 10th-oviposition day with a maximum consumption per predator of 33 T. evansi nymphs per day at the highest prey density. The ladybird beetle S. tridens is often collected associated with red spider mite colonies on solanaceous wild plants and the results suggest the potential of this ladybird beetle to control T. evansi in tomatoes crops.
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The objective of this study was to investigate immunoglobulin G (IgG) and total serum protein (TP) acquisition in newborn Santa Ines lambs fed Holstein bovine or Santa Ines ovine colostrum as well as the cell proliferation rate in the animals` intestine epithelium. At 0 h and 6 h of life, 12 newborn lambs received 250 mL of bovine 1st milking colostrum (BC) and another 12 animals received 250 mL of ovine 1st milking colostrum (OC). Blood samples were collected at 0, 6, 24. and 72 h of life. Six animals were randomly slaughtered just after birth, without colostrum intake. The other animals were randomly slaughtered at 24 and 72 h. The IgG serum concentration at 6, 24 and 72 h were significantly higher for BC, 16.32 +/- 6.19; 33.80 +/- 5.68 and 27.95 +/- 5.46 mg/mL respectively, compared with OC, 11.31 +/- 6.08, 21.02 +/- 6.53 and 19.88 +/- 7.31 mg/mL BC showed higher (P < 0.05) TP values (7.29 +/- 0.87 and 6.89 +/- 0.30 g/100 mL) at 24 and 72 h in relation to OC (5.73 +/- 1.35 and 5.69 +/- 0.57 g/100 mL). At birth, the animals showed 32.52%, 45.47% and 30.60% cells in division for the duodenum, jejunum and ileum, respectively. At 24 h, the OC animals showed lower (P < 0.0001) mitotic cell percentage in the duodenum (42.12%) and ileum (35.66%) in relation to the BC animals, 46.44% and 39.74%, respectively. At 72 h, a lower (P < 0.0001) rate of proliferation was observed in the duodenum crypts of the OC animals (36.28%) compared with BC (43.18%). The results indicate that this lacteal secretion can accelerate the epithelium renovation process and can be used as an alternative source of IgG for newborn lambs. (C) 2009 Elsevier B.V. All rights reserved.
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This study aimed to evaluate the average behavior, the genotype x environment (GxE), adaptability and stability of seven soybean cultivars at three sowing dates in Uberlandia-MG. The tests were conducted at Capim Branco Farm, belonging to the Federal University of Uberlandia. Sowing was held on october 29 (1st season), november 24 (2nd season) and december 17 (3rd season) 2007. The experimental design was a randomized, seven genotypes (UFUS Xavante, UFUS Riqueza, UFUS Guarani, UFUS Milionaria, Msoy 8001, Msoy 8411 and Msoy 8914) with three replications in each of three sowing dates. Means were compared by Tukey test at 5% probability. Analysis of adaptability and phenotypic stability of genotypes was performed using the Eberhart and Russell (1966), Lin and Binns (1988) modified by Carneiro (1998) and centroid (NASCIMENTO et al., 2009). For grain yield, the cultivar UFUS Xavante was classified as specific adaptability to environment and high stability. The other cultivars were classified as being of general adaptability. For oil content, the cultivars Msoy 8914 and UFUS Xavante behaved as high stability and was classified as having high adaptability. For the character content of protein, all cultivars behaved as wide adaptability and low stability.
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The acute poisoning of chronic renal patients during hemodialysis sessions in 1996 in Caruaru City (Pernambuco State, Brazil) stimulated an intensive search for the cause of this severe complication. This search culminated in the identification of microcystins (MC), hepatotoxic cyclic heptapeptides produced by cyanobacteria, as the causative agents. More than ten years later, additional research data provides us with a better understanding of the factors related to cyanobacterial bloom occurrence and production of MC in Brazil and other South American countries. The contamination of water bodies and formation of toxic blooms remains a very serious concern, especially in countries in which surface water is used as the main source for human consumption. The purpose of this review is to highlight the discoveries of the past 15 years that have brought South American researchers to their current level of understanding of toxic cyanobacteria species and that have contributed to their knowledge of factors related to MC production, mechanisms of action and consequences for human health and the environment. (C) 2010 Elsevier Ltd. All rights reserved.
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Cylindrospermopsin (CYN) belongs to a group of toxins produced by several strains of freshwater cyanobacteria. It is a compact zwitterionic molecule composed of a uracil section and a tricyclic guanidinium portion with a primarily hepatotoxic effect. Using low multi-stage and high-resolution mass spectrometry, the gas-phase reactions of this toxin have been investigated. Our data show that collision-induced dissociation (CID) spectra of CYN are dominated by neutral losses, and three major initial fragmentation pathways are clearly distinguishable. Interestingly, comparative analysis of protonated and cationizated molecules showed a significant difference in the balance of the SO(3) and terminal ring elimination. These data indicate that the differential ion mobility of H(+), Li(+), Na(+) and K(+) leads to different fragmentation pathways, giving rise to mass spectra with different profiles. Copyright (C) 2008 John Wiley & Sons, Ltd.
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Deficiencies of complement proteins of the classical pathway are strongly associated with the development of autoimmune diseases. Deficiency of Clr has been observed to occur concomitantly with deficiency in Cls and 9 out of 15 reported cases presented systemic lupus erythernatosus (SLE). Here, we describe a family in which all four children are deficient in Cls but only two of them developed SLE. Hemolytic activity mediated by the alternative and the lectin pathways were normal, but classical pathway activation was absent in all children`s sera. Cls was undetectable, while in the parents` sera it was lower than in the normal controls. The levels of Clr observed in the siblings and parents sera were lower than in the control, while the concentrations of other complement proteins (C3, C4, MBL and MASP-2) were normal in all family members. Impairment of Cls synthesis was observed in the patients` fibroblasts when analyzed by confocal microscopy. We show that all four siblings are homozygous for a mutation at position 938 in exon 6 of the Cls cDNA that creates a premature stop codon. Our investigations led us to reveal the presence of previously uncharacterized splice variants of Cls mRNA transcripts in normal human cells. These variants are derived from the skipping of exon 3 and from the use of an alternative 3` splice site within intron I which increases the size of exon 2 by 87 nucleotides. (c) 2007 Elsevier Ltd. All rights reserved.
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We previously reported the anti-inflammatory activity of Lafoensia pacari extract in Toxocara canis infection, a model of systemic IL-5-dependent eosinophil migration. In the present study, we describe the kinetics of the anti-inflammatory activity of L. pacari extract and compare it with dexamethasone. T canis-infected mice were submitted to different treatment protocols and the cells present in bronchoalveolar space and peritoneal cavity were collected at the end of each treatment period. The results showed that L. pacari extract effectively inhibited eosinophil migration only when the treatment was initiated before the peak of eosinophil migration (1st to 18th; 12th to 18th and 12th to 24th day post-infection). When eosinophil migration was established, administration of L. pacari extract had no effect on it (treatment 18th to 24th day post-infection). Dexamethasone was effective in inhibiting eosinophil migration in all periods studied. We suggest that L pacari extract can potentially be a natural alternative treatment of eosinophilic diseases. (c) 2007 Published by Elsevier GmbH.
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Subtropical grasslands are low in organic matter digestibility (OMD) (0.60) and nitrogen (N) (15 g/kg) for much of the year and this limits cattle production which is characterized by low calving rates and low weaning weights. Production has been based on Bos taurus British breeds of cattle but this is changing and now many breeding herds comprise B, indicus cows and their crosses. This change has increased some aspects of production, but low calving rates persist. A 4-year study was undertaken with a view to improve calving rates and weaner output by supplementing cows grazing either native or improved pastures with a high protein oilseed meal (cottonseed meal; CSM) on four sites. These sites were subdivided into a total of 36 paddocks to allow for two replications in a 3 breeds X 3 supplementation rates X 2 pastures factorial design. Selected cows (no. = 216) from Hereford (H), Brahman (B) and Brahman X Hereford (BH) breed types were set to graze either native pastures (0.45 to 0.62 OMD, 8 to 15 g N per kg; low quality) or improved pastures (0.47 to 0.67 OA ID, 10 to 22 g N per kg; medium quality). Cows were given either 0, 750 or 1500 g/day of CSM for 130 days from calving until 4 weeks into a 12- to 13-week mating period. The CSM was given as two meals per week. Live weight at mating of cows on the low quality pasture was increased (P < 0.01) over those not supplemented by feeding either 750 g CSM per day (H and B cows) or 1500 g CSM per day tall cows). There was no significant effect of supplementation on the mating weights of B cows grazing the medium quality sites. Calving rate of B cows was not increased by their supplementation on either low (4-year mean 58.3 %) or medium quality pastures (66.8%) but did tend to be higher in H cows when supplemented at 1500 g CSM per day on the low (66.7 v. 78.0 (s.e. 6.09) %; P < 0.1) and medium quality pastures (70.5 v. 93.5 (s.e. 4.72) %). An increased calving rate (65.8 (s.e. 6.6) % to 83.2 (s.e. 5.82) % in supplemented BH cows grazing low quality pastures approached significance (P < 0.1) when given CSM at 1500 g/day but there was no increased trend in calving rate when this breed type was supplemented on medium quality pastures. Weaning weights of calves from and B and BH cows were increased (P < 0.05) by supplementation of their darns at 750 g/day and for calves weaned from H cows supplemented at 1500 g/day of CSM. Supplementation at 1500 g/day on low quality pastures increased weaner output per cow mated by 120% for H, by 65% for BH cows and by 50% for B cows. Weaner output was increased by 34 and 40%, respectively, for B and H cows when supplemented at 750 g/day and grazing medium quality pastures but there teas no significant effect of supplementation on output from BH cows. Responses in many parameters differed between years. These results were interpreted as a response to the protein in the oilseed meal supplement by B, taurus and B. taurus X B. indicus cross cows grazing on the subtropical pastures. The study also highlighted that responses to the meal differed between breed types, between the quality of the grazed pasture and between the years of supplementation.
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Albicidins are important factors in systemic pathogenesis by Xanthomonas albilineans, which causes the devastating leaf scald disease of sugar cane. They ale also of substantial interest as antibiotics that selectively block prokaryote DNA replication. Albicidin biosynthesis is highly sensitive to medium composition. An optimized, chemically defined medium (SMG3) yielded 30-fold more albicidin from half the accumulated biomass, relative to sucrose peptone (SP) medium. Phosphate starvation stimulated albicidin production in SMG3 and SP media. Addition of other amino acids, ammonium ions or peptones to the defined medium increased the growth rate of X albilineans XA3, but differentially inhibited albicidin biosynthesis. Knowledge of these factors indicates new approaches to understanding mechanisms of pathogenesis and resistance to sugar cane leaf scald disease, and to strain improvement for production of albicidin antibiotics.
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Aim: To model the impact of rising rates of cannabis use on the incidence and prevalence of psychosis under four hypotheses about the relationship between cannabis use and psychosis. Methods: The study modelled the effects on the prevalence of schizophrenia over the lifespan of cannabis in eight birth cohorts: 1940-1944, 1945-1949, 1950-1954, 1955-1959, 1960-1964, 1965-1969, 1970-1974, 1975-1979. It derived predictions as to the number of cases of schizophrenia that would be observed in these birth cohorts, given the following four hypotheses: (1) that there is a causal relationship between cannabis use and schizophrenia; (2) that cannabis use precipitates schizophrenia in vulnerable persons; (3) that cannabis use exacerbates schizophrenia; and (4) that persons with schizophrenia are more liable to become regular cannabis users. Results: There was a steep rise in the prevalence of cannabis use in Australia over the past 30 years and a corresponding decrease in the age of initiation of cannabis use. There was no evidence of a significant increase in the incidence of schizophrenia over the past 30 years. Data on trends the age of onset of schizophrenia did not show a clear pattern. Cannabis use among persons with schizophrenia has consistently been found to be more common than in the general population. Conclusions: Cannabis use does not appear to be causally related to the incidence of schizophrenia, but its use may precipitate disorders in persons who are vulnerable to developing psychosis and worsen the course of the disorder among those who have already developed it. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.
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Background: The Royal Australian and New Zealand College of Psychiatrists is co-ordinating the development of clinical practice guidelines (CPGs) in psychiatry, funded under the National Mental Health Strategy (Australia) and the New Zealand Health Funding Authority. This paper presents CPGs for schizophrenia and related disorders. Over the past decade schizophrenia has become more treatable than ever before. A new generation of drug therapies, a renaissance of psychological and psychosocial interventions and a first generation of reform within the specialist mental health system have combined to create an evidence-based climate of realistic optimism. Progressive neuroscientific advances hold out the strong possibility of more definitive biological treatments in the near future. However, this improved potential for better outcomes and quality of life for people with schizophrenia has not been translated into reality in Australia. The efficacy-effectiveness gap is wider for schizophrenia than any other serious medical disorder. Therapeutic nihilism, under-resourcing of services and a stalling of the service reform process, poor morale within specialist mental health services, a lack of broad-based recovery and life support programs, and a climate of tenacious stigma and consequent lack of concern for people with schizophrenia are the contributory causes for this failure to effectively treat. These guidelines therefore tackle only one element in the endeavour to reduce the impact of schizophrenia. They distil the current evidence-base and make recommendations based on the best available knowledge. Method: A comprehensive literature review (1990-2003) was conducted, including all Cochrane schizophrenia reviews and all relevant meta-analyses, and a number of recent international clinical practice guidelines were consulted. A series of drafts were refined by the expert committee and enhanced through a bi-national consultation process. Treatment recommendations: This guideline provides evidence-based recommendations for the management of schizophrenia by treatment type and by phase of illness. The essential features of the guidelines are: (i) Early detection and comprehensive treatment of first episode cases is a priority since the psychosocial and possibly the biological impact of illness can be minimized and outcome improved. An optimistic attitude on the part of health professionals is an essential ingredient from the outset and across all phases of illness. (ii) Comprehensive and sustained intervention should be assured during the initial 3-5 years following diagnosis since course of illness is strongly influenced by what occurs in this 'critical period'. Patients should not have to 'prove chronicity' before they gain consistent access and tenure to specialist mental health services. (iii) Antipsychotic medication is the cornerstone of treatment. These medicines have improved in quality and tolerability, yet should be used cautiously and in a more targeted manner than in the past. The treatment of choice for most patients is now the novel antipsychotic medications because of their superior tolerability and, in particular, the reduced risk of tardive dyskinesia. This is particularly so for the first episode patient where, due to superior tolerability, novel agents are the first, second and third line choice. These novel agents are nevertheless associated with potentially serious medium to long-term side-effects of their own for which patients must be carefully monitored. Conventional antipsychotic medications in low dosage may still have a role in a small proportion of patients, where there has been full remission and good tolerability; however, the indications are shrinking progressively. These principles are now accepted in most developed countries. (vi) Clozapine should be used early in the course, as soon as treatment resistance to at least two antipsychotics has been demonstrated. This usually means incomplete remission of positive symptomatology, but clozapine may also be considered where there are pervasive negative symptoms or significant or persistent suicidal risk is present. (v) Comprehensive psychosocial interventions should be routinely available to all patients and their families, and provided by appropriately trained mental health professionals with time to devote to the task. This includes family interventions, cognitive-behaviour therapy, vocational rehabilitation and other forms of therapy, especially for comorbid conditions, such as substance abuse, depression and anxiety. (vi) The social and cultural environment of people with schizophrenia is an essential arena for intervention. Adequate shelter, financial security, access to meaningful social roles and availability of social support are essential components of recovery and quality of life. (vii) Interventions should be carefully tailored to phase and stage of illness, and to gender and cultural background. (viii) Genuine involvement of consumers and relatives in service development and provision should be standard. (ix) Maintenance of good physical health and prevention and early treatment of serious medical illness has been seriously neglected in the management of schizophrenia, and results in premature death and widespread morbidity. Quality of medical care for people with schizophrenia should be equivalent to the general community standard. (x) General practitioners (GPs)s should always be closely involved in the care of people with schizophrenia. However, this should be truly shared care, and sole care by a GP with minimal or no special Optimal treatment of schizophrenia requires a multidisciplinary team approach with a consultant psychiatrist centrally involved.
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BACKGROUND: Tacrolimus ointment has been shown to be effective in treatment of atopic dermatitis. OBJECTIVES: To evaluate the efficacy and safety of 0.03% tacrolimus ointment (Protopic(R)) in pediatric patients with mild, moderate and severe atopic dermatitis. METHODS.. Open, non-comparative, multicentric study carried out in Brazil. 174 patients (ages from two to 10) with mild to severe atopic dermatitis were included. Patients were instructed to apply Protopic(R) twice a day for six weeks. Primary efficacy criterion was clinical improvement >= 90% assessed by the pbysician (Clinical Response Global Evaluation Scale). Other efficacy criteria included reduction of the Eczema Area Severity Index (EASI), decrease of the affected body surface area (%BSA) and evaluation of the itching by the patients or their guardians (visual analogical scale). Safety was evaluated by adverse events reported by patients and/or guardians or by investigators. RESULTS: Thirty-three percent of patients showed clinical improvement 90%. 45.5% of patients (1st week) decreased EASI and 61.8% (6th week) (p<0,001). %BSA decreased 30.4% and 55.5% in the first and sixth week. improvement was also significant when measured by itching (p<0, 001). Most frequent adverse effects were: burning and itching. CONCLUSION: 0.03% tacrolimus ointment is a safe and effective therapy for mild to severe atopic dermatitis in pediatric patients.