SMT-Based Bounded Model Checking of Fixed-Point Digital Controllers

Digital controllers have several advantages with respect to their flexibility and design's simplicity. However, they are subject to problems that are not faced by analog controllers. In particular, these problems are related to the finite word-length implementation that might lead to overflows, limit cycles, and time constraints in fixed-point processors. This paper proposes a new method to detect design's errors in digital controllers using a state-of-the art bounded model checker based on satisfiability modulo theories. The experiments with digital controllers for a ball and beam plant demonstrate that the proposed method can be very effective in finding errors in digital controllers than other existing approaches based on traditional simulations tools

Gift Young Engineers: An Extra-Curricular Initiative for Updating Computer and Electrical Engineering Courses

The curricula of engineering courses are well defined by the central government for all Brazilian universities. Indeed, there are some mandatory determinations that must be fulfilled prior to the accreditation of any engineering course in Brazil. Modifications must be submitted for evaluation beforehand, resulting in a process that sometimes takes years to be approved. That is a secure way to guarantee that the fundamentals of each engineering program will be part of the students’ carrier all over the country, and at the same time a problem when you need to introduce new technological subjects. That poses a problem when you have new demands for technological curricular components that could express the actual state of the art of modern subjects. Trying to solve these issues some professors from the Federal University of Amazonas developed a flexible extra-curricular program for electrical and computer engineering courses, named Gift Young Engineers. This paper describes the philosophy of these extra-curricular programs. Some examples of successful particular partnerships are also discussed. Indeed the proposed training programs for Digital TV Systems (hardware and software) will be presented and analyzed in details. The obtained results will also be discussed in order to contribute to similar experiences worldwide

Existe relação entre o número de microêmbolos e a evolução neurológica nas cirurgias de revascularização miocárdica?

Coronary artery bypass surgery (CABG) without cardiopulmonary bypass (CPB) may potentially reduce the number of microembolic signals (MES) associated with aortic manipulation or generated by the pump circuit, resulting in a better neurologic outcome after surgery. Our aim was to compare the frequency of MES and neurologic complications in CABG with and without CPB. Twenty patients eligible to routine CABG without CPB were randomized to surgery with CPB and without CPB and continuously monitored by transcranial Doppler. Neurologic examination was performed in all patients before and after surgery. The two groups were similar with respect to demographics, risk factors, grade of aortic atheromatous disease and number of grafts. The frequency of MES in the nonCPB group was considerably lower than in CPB patients, however, we did not observe any change in the neurologic examination during the early postoperative period. Neurologic complications after CABG may be related to the size and composition of MES rather than to their absolute numbers. A large prospective multicentric randomized trial may help to elucidate this complex issue.A cirurgia de revascularização miocárdica sem circulação extracorpórea (CEC) pode estar relacionada com uma potencial redução no número dos microêmbolos (ME) associados com a manipulação da aorta ou gerados pelo equipamento, com consequente redução do risco de complicações neurológicas nestes pacientes. Nosso objetivo foi comparar a frequência de ME e de complicações neurológicas em pacientes operados sem e com CEC. Vinte pacientes selecionados para revascularização miocárdica eletiva sem CEC foram randomizados para cirurgia com e sem CEC. A monitorização contínua com Doppler transcraniano foi realizada durante todo o procedimento nos dois grupos e os pacientes foram examinados antes e após a cirurgia. Os grupos não apresentaram diferenças significativas em relação aos aspectos demográficos, fatores de risco, grau de ateromatose de aorta e número de pontes realizadas. A frequência de ME no grupo operado sem CEC foi significativamente menor do que no grupo operado com CEC, entretanto, nenhum paciente apresentou alterações no exame neurológico no período pós-operatório inicial. Esta observação pode sugerir que as complicações neurológicas possam estar mais relacionadas com o tamanho e a composição, do que com o número de ME. Somente um estudo prospectivo com maior número de pacientes poderá esclarecer este assunto.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Department of NeurologyUNIFESP, EPM, Department of NeurologySciEL

BALB/c Mice Infected with Antimony Treatment Refractory Isolate of Leishmania braziliensis Present Severe Lesions due to IL-4 Production

Leishmaniasis is a neglected disease that affects more than 12 million people worldwide. In Brazil, the cutaneous disease is more prevalent with about 28,000 new cases reported each year, and L. braziliensis is the main causative agent. The interesting data about the infection with this parasite is the wide variety of clinical manifestations that ranges from single ulcerated lesions to mucocutaneous and disseminated disease. However, experimental models to study the infection with this parasite are difficult to develop due to high resistance of most mouse strains to the infection, and the mechanisms underlying the distinct manifestations remain poorly understood. Here, the authors use a mouse experimental model of infection with different L. braziliensis isolates, known to induce diseases with distinct severity in the human hosts, to elucidate immune mechanisms that may be involved in the different manifestations. They showed that distinct parasite isolates may modulate host response, and increased IL-4 production and Arg I expression was related to more severe disease, resulting in longer length of disease with larger lesions and reduced parasite clearance. These findings may be useful in the identification of immunological targets to control L. braziliensis infection and potential clinical markers of disease progression

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years