35 research outputs found
Bipolaris yamadae as a causal agent of brown leaf spot in Megathyrsus maximus in Brazil
Guinea grass (Megathyrsus maximus)is widely used as a forage crop in Brazil, but its production faces disease threats. Recently, new symptoms, such as oblong to irregular brown lesions on leaves, have emerged in M. maximus across the country. Particularly severe symptoms were observed in the BRS Tamani cultivar, and some other genotypes showed lesion coalescence and intense leaf necrosis. This study aimed to identify the cause of these symptoms. A fungus was isolated from the lesions and, using morphological measurements and molecular analysis of the ITS, GPDH and TEF-1α genes, it was identified as Bipolaris yamadae. Pathogenicity tests confirmed its ability to cause disease in M. maximus cv. Tamani. A field survey of 205 M. maximus genotypes showed severe symptoms in 8.35 % of the materials
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
Optimized allocation of sectionalizing switches and control and protection devices for reliability indices improvement in distribution systems
Reliability of power supply is related, among other factors, to the control and protection devices allocation in feeders of distribution systems. In this way, optimized allocation of sectionalizing switches and protection devices in strategic points of distribution circuits, improves the quality of power supply and the system reliability indices. In this work, it is presented a mixed integer non-linear programming (MINLP) model, with real and binary variables, for the sectionalizing switches and protection devices allocation problem, in strategic sectors, aimed at improving reliability indices, increasing the utilities billing and fulfilling exigencies of regulatory agencies for the power supply. Optimized allocation of protection devices and switches for restoration, allows that those faulted sectors of the system can be isolated and repaired, re-managing loads of the analyzed feeder into the set of neighbor feeders. Proposed solution technique is a Genetic Algorithm (GA) developed exploiting the physical characteristics of the problem. Results obtained through simulations for a real-life circuit, are presented. © 2004 IEEE
Improved Fault Location on Distribution Feeders Based on Matching During-Fault Voltage Sags
A fault location algorithm for distribution feeders based on matching during-fault voltage sags is presented. The basic principle of the algorithm is based on the fact that when a fault occurs on the feeder, voltage sags propagate presenting different characteristics for each feeder node. Knowing the voltage sag characteristics, it is possible to locate the faulty node or the faulty area of the feeder. This voltage-based approach ensures the efficiency and robustness of the algorithm, which provides suitable and accurate results. An overhead, three-phase, three-wire, 13.8 kV, 134-node, real-life feeder model is used to evaluate the algorithm. Test results show that the algorithm is quite suitable due to not only the faulted point being located, but also a faulted area being identified providing important information to direct the maintenance crew seeking to repair any fault inflicted damage.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Ticks infesting birds in Atlantic Forest fragments in Rio Claro, State of Sao Paulo, Brazil Carrapatos infestando aves em fragmentos de Mata Atlântica em Rio Claro, São Paulo, Brasil
In the present study, we report tick infestations on wild birds in plots of the Atlantic Forest reforested fragments with native species and plots reforested with Eucalyptus tereticornis in the municipality of Rio Claro, State of Sao Paulo, Brazil. A total of 256 birds were captured: 137 individuals of 33 species, in planted native forest; and 128 individuals of 37 species, in planted Eucalyptus tereticornis forest. Nymphs of two tick species were found on the birds: Amblyomma calcaratum and Amblyomma longirostre, the former was more abundant in the fragments reforested with Atlantic forest native species, and the latter in the fragment reforested with E. tereticornis. New host records were presented for A. calcaratum.O presente estudo apresenta infestações de carrapatos em aves silvestres em fragmentos de reflorestamento com espécies nativas e fragmentos de reflorestamento com Eucalyptus tereticornis no município de Rio Claro, São Paulo. No total foram capturadas 265 aves, sendo 137 indivíduos de 33 espécies nas áreas de reflorestamento com espécies nativas e 128 indivíduos de 37 espécies nas áreas reflorestadas com Eucalyptus tereticornis. Ninfas de duas espécies de carrapatos foram registradas: Amblyomma calcaratum e Amblyomma longirostre, sendo a primeira mais abundante na área nativa e a segunda na área de Eucalyptus tereticornis. Novos registros de hospedeiros para A. calcaratum são apresentados
MOLECULAR DETECTION OF CLARITHROMYCIN AND FLUOROQUINOLONES RESISTANCE IN HELICOBACTER PYLORI INFECTION, DIRECTLY APPLIED TO GASTRIC BIOPSIES, IN AN URBAN BRAZILIAN POPULATION
ABSTRACT Background - Antimicrobial resistance is the major factor leading to eradication failure in H. pylori treatment. Molecular tests are useful to detect genetic mutations predictive of clarithromycin and fluoroquinolones resistance. Knowledge of the local prevalence rate of resistance is important to define the best recommended treatment. Objective - To assess the prevalence of primary resistance of H. pylori to clarithromycin and fluoroquinolones, using a molecular test, in a Southeastern urban Brazilian population. Methods - A total of 72 H. pylori seropositive patients [65% female, mean age 39 (19-73) years] never treated before for this infection were studied. All patients underwent gastroscopy in addition to antrum and corpus biopsies and molecular test GenoType HelicoDR (Hain Life Science, Germany) to detect H. pylori and point mutations in genes responsible for clarithromycin and fluoroquinolone resistance. The molecular procedure was divided into three steps: DNA extraction from biopsy samples, a multiplex amplification with biotinylated primers and a reverse hybridization. The most frequent point mutations involved in resistance to the two antibiotics were evaluated. Results - Resistance to clarithromycin was detected in nine (12.5%) patients and to fluoroquinolones in eight (11.1%) patients. The point mutation A2147G was the most common (77.8%) among resistant strains to clarithromycin. In 50% of the resistant strains to fluoroquinolones, the mutant codon couldn't be identified. Conclusion - The resistance rates to clarithromycin and fluorquinolones in a large urban population in the Southeast of Brazil were acceptable, suggesting that these drugs remain appropriate options to first and second-line of H. pylori treatment. The molecular test represents an adequate diagnostic tool for monitoring H. pylori resistance