3,612 research outputs found
Economic Design of X Control Charts for Monitoring a First Order Autoregressive Process
In this paper we deal with the economic design of an X control chart
used to monitor a quality characteristic whose observations fit to a first order
autoregressive model. The Duncan cost model is used to select the control
chart parameters, namely the sample size (n), the sampling interval (h) and
the control limit coefficient (k), that lead to the optimal monitoring cost. We
found that the autocorrelation has an adverse effect on the chart’s power, on
the false alarm risk and on the cost. It also increases n and h and decreases
k. To counteract this undesired effect we considered setting up the subgroups
using non-sequential observations. It is shown that this sampling strategy
significantly reduces the monitoring cost.
Indução da germinação de sementes de Urochloa mosambicensis com nitrato de potássio.
Este trabalho teve como objetivo avaliar a qualidade fisiológica e superação de dormência em sementes recém-colhidas de 14 diferentes genótipos de Urochloa sp
Th e Non-Central Chi-Square Chart with Double Sampling
In this article, we consider a non-central chi-square chart with double sampling (DS χ2 chart) to control the process mean and variance. As in the case of Shewhart control charts, samples of fi xed size are taken from the process at regular time intervals; however, the sampling is performed in two stages. Let X be the process quality variable being measured. During the fi rst stage, one item of the sample is inspected; if its X value is close
to the target value of the process mean, then the sampling is interrupted. Otherwise, the sampling goes on to the second stage, where the remaining items are inspected and a
non-central chi-square statistic, say T, is computed taking into account all n items of the sample, that is, their X values. A signal is triggered when the sample point given by the
T value falls above the upper control limit of the proposed chart. The DS χ2 chart performs better than the joint X and R charts, except when there is a large change in the process mean. Furthermore, if the DS χ2 chart is used for monitoring diameters, volumes, weights, etc., then the employment of appropriate devices, such as go-no-go gauges can reduce the effort to decide if the sampling should go to the second stage or not
Determination of pharmacological interactions of uliginosin B, a natural phloroglucinol derivative, with amitriptyline, clonidine and morphine by isobolographic analysis
AbstractUliginosin B is a natural phloroglucinol derivative, obtained from Hypericum species native to South America. Previous studies have shown that uliginosin B presents antidepressant-like and antinociceptive effects. Although its mechanism of action is still not completely elucidated, it is known that it involves the activation of monoaminergic neurotransmission. The aim of the current study was to further investigate the antinociceptive mechanism of action of uliginosin B by combining it with different drugs used for treating pain in clinical practice. The intraperitoneal administration of uliginosin B, morphine, amitriptyline and clonidine, alone or in mixture, produced a dose-dependent antinociceptive effect in the hot-plate assay in mice. The effect of the mixtures of drugs was studied using an adapted isobologram analysis at the effect level of 50% of the maximal effect observed. The analysis showed that the interactions between uliginosin B and morphine was synergistic, while the interactions between uliginosin B and amitriptyline or clonidine were additive. These findings point to uliginosin B as a potential adjuvant for pain pharmacotherapy, especially for opioid analgesia
Enterococcal meningitis caused by Enterococcus casseliflavus. First case report
BACKGROUND: Enterococcal meningitis is an uncommon disease usually caused by Enterococcus faecalis and Enterococcus faecium and is associated with a high mortality rate. Enterococcus casseliflavus has been implicated in a wide variety of infections in humans, but never in meningitis. CASE PRESENTATION: A 77-year-old Italian female presented for evaluation of fever, stupor, diarrhea and vomiting of 3 days duration. There was no history of head injury nor of previous surgical procedures. She had been suffering from rheumatoid arthritis for 30 years, for which she was being treated with steroids and methotrexate. On admission, she was febrile, alert but not oriented to time and place. Her neck was stiff, and she had a positive Kernig's sign. The patient's cerebrospinal fluid was opalescent with a glucose concentration of 14 mg/dl, a protein level of 472 mg/dl, and a white cell count of 200/μL with 95% polymorphonuclear leukocytes and 5% lymphocytes. Gram staining of CSF revealed no organisms, culture yielded E. casseliflavus. The patient was successfully treated with meropenem and ampicillin-sulbactam. CONCLUSIONS: E. casseliflavus can be inserted among the etiologic agents of meningitis. Awareness of infection of central nervous system with Enterococcus species that possess an intrinsic vancomycin resistance should be increased
Genomic evolution and complexity of the Anaphase-promoting Complex (APC) in land plants
<p>Abstract</p> <p>Background</p> <p>The orderly progression through mitosis is regulated by the Anaphase-Promoting Complex (APC), a large multiprotein E<sub>3 </sub>ubiquitin ligase that targets key cell-cycle regulators for destruction by the 26 S proteasome. The APC is composed of at least 11 subunits and associates with additional regulatory activators during mitosis and interphase cycles. Despite extensive research on APC and activator functions in the cell cycle, only a few components have been functionally characterized in plants.</p> <p>Results</p> <p>Here, we describe an in-depth search for APC subunits and activator genes in the Arabidopsis, rice and poplar genomes. Also, searches in other genomes that are not completely sequenced were performed. Phylogenetic analyses indicate that some APC subunits and activator genes have experienced gene duplication events in plants, in contrast to animals. Expression patterns of paralog subunits and activators in rice could indicate that this duplication, rather than complete redundancy, could reflect initial specialization steps. The absence of subunit APC7 from the genome of some green algae species and as well as from early metazoan lineages, could mean that APC7 is not required for APC function in unicellular organisms and it may be a result of duplication of another tetratricopeptide (TPR) subunit. Analyses of TPR evolution suggest that duplications of subunits started from the central domains.</p> <p>Conclusions</p> <p>The increased complexity of the APC gene structure, tied to the diversification of expression paths, suggests that land plants developed sophisticated mechanisms of APC regulation to cope with the sedentary life style and its associated environmental exposures.</p
Oral colonization by yeasts in HIV-positive patients in Brazil
INTRODUCTION: In HIV-infected patients, colonization of the oral cavity by potential pathogenic yeast may lead to development of systemic fungemia. We evaluated the prevalence of yeast in the oral cavity of Brazilian HIV-positive patients and verified whether or not the species characterized were enzymatically active. Furthermore, the species identified were tested for their susceptibility to antifungal treatment. METHODS: Patient saliva and oropharyngeal candidiasis samples were collected from 60 seropositive HIV patients and identified by the API20C system. Enzymatic activity was evaluated by the production of proteinase and phospholipase. Susceptibility to antifungal treatments were determined using the broth microdilution method. RESULTS: the most commonly isolated species were C. albicans (51.56%) followed by non-albicans Candida species (43.73%), Trichosporon mucoides (3.12%) and Kodamaea ohmeri (1.56%). Oral colonization by association of different species was observed in 42% of the patients. Enzymatic activity was verified in most of species isolated, except for C. glabrata, C. lusitaniae and C. guilliermondii. Resistance to Fluconazole and Amphotericin B was observed in isolates of C. albicans, C. glabrata, C. parapsilosis, C. krusei, and K. ohmeri. CONCLUSION: HIV-positive patients are orally colonized by single or multiple species of yeast that are occasionally resistant to Fluconazole or Amphotericin B.INTRODUÇÃO: Em pacientes infectados pelo HIV, a colonização da cavidade bucal por leveduras patogênicas pode levar ao desenvolvimento de fungemias. No presente estudo, avaliamos a prevalência de leveduras na cavidade bucal de pacientes HIV-positivos e verificamos se as espécies isoladas foram enzimaticamente ativas. Além disso, as espécies identificadas foram testadas quanto à suscetibilidade a antifúngicos. MÉTODOS: Amostras de saliva e de candidose orofaríngea foram coletadas de 60 pacientes soropositivos para HIV e identificados pelo sistema API20C. A atividade enzimática foi avaliada pela produção de proteinase e fosfolipase. A suscetibilidade a antifúngicos foi determinada utilizando o método de microdiluição em caldo. RESULTADOS: As espécies mais comumente isoladas foram C. albicans (51,56%), seguido por espécies de Candida não-albicans (43,73%), Trichosporon mucoides (3,12%) e Kodamaea ohmeri (1,56%). A colonização bucal por associação de diferentes espécies foi observada em 42% dos pacientes. A atividade enzimática foi verificada na maioria das espécies isoladas, com exceção de C. glabrata, C. lusitaniae e C. guilliermondii. Resistência ao fluconazol e anfotericina B foi observada em isolados de C. albicans, C. glabrata, C. parapsilosis, C. krusei, e K. ohmeri. CONCLUSÃO: Os pacientes HIV-positivos são colonizados por espécies únicas ou múltiplas de levedura que ocasionalmente são resistentes ao fluconazol ou anfotericina B
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Early exposure to high-sucrose diet leads to deteriorated ovarian health
Background: The metabolic syndrome (MetS) is correlated with disorders of the reproductive system, such as the polycystic ovary syndrome (PCOS). While consumption of a diet rich in carbohydrates is linked to the development of MetS, it is still unclear if this diet leads to ovarian dysfunction and PCOS.
Objectives: We investigated the influence of a high-sucrose diet (HSD) on the ovarian milieu of Wistar rats and studied the correlation between high consumption of sugary drink and the prevalence of PCOS in women.
Methods: Wistar rats were given standard laboratory diet (CTR, 10% sucrose, n = 8) or HSD (HSD, 25% sucrose, n = 8) from postnatal day 21 to 120. The animals were evaluated weekly to calculate food intake, feed efficiency and weight gain. Both onset of puberty and estrous cycle were monitored. Metabolic serum biochemistry, organ morphometry and ovarian histology were performed upon euthanasia. In parallel, fixed-effects multiple linear regression analysis was carried out using data from Brazilian states (459 state-year observations) to test the correlation between the consumption of sugar-sweetened beverages and the prevalence of PCOS.
Results: HSD animals were not obese, but showed increased adipose tissue accumulation, hyperglycaemia and insulin resistance when compared to CTR. Interestingly HSD rats also entered puberty earlier than CTR. Moreover, ovaries from HSD animals had an increased number of atretic antral follicles and cystic follicles, which were correlated with hypertrophy of periovarian adipocytes. Finally, there was a positive correlation between the intake of sugary drinks and prevalence of PCOS in women of reproductive age.
Conclusions: HSD ingestion leads to ovarian dysfunction in rats and could be correlated with PCOS in women, suggesting these alterations could lead to public health issues. Therefore, we reinforce the deleterious impact of HSD to the ovarian system and suggest that the reduction of added sugars intake could be beneficial to ovarian health
Biodiversidade, população e economia: uma região de mata atlântica [Biodiversity, Population, and Economy: a region of atlantic forest]
Minas Gerais; Rio Doce; mata atlântica; atlantic forest; sustainable development; conservation; regional development; environment
Propagação e manejo fitossanitário de mudas de maniçoba.
Neste trabalho são apresentadas as principais recomendações para alcançar sucesso na propagação de mudas de maniçoba por meio de sementes ou por meio de estaquia em condições de viveiro, bem como o manejo fitossanitário, com o objetivo de direcionar de forma adequada as práticas adotadas por viveiristas e agricultores na condução desta etapa inicial do desenvolvimento das plantas.O principal fator para quebra de dormência em sementes de maniçoba é o tempo de armazenamento de no mínimo 1 ano. Se utilizado em conjunto com a escarificação mecânica com lixa e imersão em água, por 2 horas, não haverá grandes dificuldades para a produção de mudas por este método. Para fixação das qualidades genéticas de boas matrizes de maniçoba (produção de clones), a propagação de mudas por estaquia é a escolha correta. No caso da maniçoba, este método é mais rápido e fácil para a produção por pequenos produtores. Neste caso, a escolha da matriz é o principal fator a ser observado na produção de mudas de maniçoba.bitstream/item/219143/1/COMUNICADO-TECNICO-179.pd
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