NUMERICAL STUDY OF COOLING BY TANGENTIAL SYNTHETIC JET

Modern electronics are becoming more compact and with higher processing power, which translates into a demand for higher heat dissipation. Current electronic "coolers," which are based on the combination of fans and heat sinks, are becoming unable to provide sufficient heat dissipation since they rely primarily on generating large volumetric flowrates of air to achieve their results. As an alternative, synthetic jets are under consideration due to their known property to enhance turbulence and heat transfer. Synthetic jets are produced by the oscillation of a membrane in a sealed cavity equipped with an orifice. For this study, a numerical model of channel mounted with a heating element on one surface and a synthetic jet directed to blow along the wall was constructed on ANSYS CFX. Heat dissipation provided by the synthetic jet was analyzed with respect to changes in Reynolds number, pulsing frequency and placement of the heated element. Results were compared to a conventional technique represented by a steady channel flow of equivalent mass flow rate to the average flow induced by the synthetic jet. Results showed that the synthetic jet formed a thin layer of intense vorticity along the targeted surface with cooling greatly outperforming conventional techniques. Synthetic jet cooling was also determined to be most affected by jet velocity and Reynolds number while pulsing frequency and placement of the heated element were not as influential

Spontaneous emission and teleportation in cavity QED

In this work, we consider atomic spontaneous emission in a system consisting of two identical two-level atoms interacting dispersively with the quantized electromagnetic field in a high-Q cavity. We investigate the destructive effect of the atomic decay on the generation of maximally entangled states, following the proposal by Zheng S B and Guo G C (2000 Phys. Rev. Lett. 85 2392). In particular, we analyze the fidelity of teleportation performed using such a noisy channel and calculatethe maximum spontaneous decay rate we may have in order to realize teleportation.Comment: 11 pages, 6 figures, LaTe

Microplastics: a review of policies and responses

Although (micro)plastic contamination is a worldwide concern, most scientific literature only restates that issue rather than presenting strategies to cope with it. This critical review assembles the current knowledge on policies and responses to tackle plastic pollution, including peer-reviewed scientific literature, gray literature and relevant reports to provide: (1) a timeline of policies directly or indirectly addressing microplastics; (2) the most up-to-date upstream responses to prevent microplastics pollution, such as circular economy, behavioral change, development of bio-based polymers and market-based instruments as well as source-specific strategies, focusing on the clothing industry, tire and road wear particles, antifouling paints and recreational activities; (3) a set of downstream responses tackling microplastics, such as waste to energy, degradation, water treatment plants and litter clean-up strategies; and examples of (4) multifaceted responses focused on both mitigating and preventing microplastics pollution, e.g., approaches implemented in fisheries and aquaculture facilities. Preventive strategies and multifaceted responses are postulated as pivotal to handling the exacerbated release of microplastics in the environment, while downstream responses stand out as auxiliary strategies to the chief upstream responses. The information gathered here bridges the knowledge gaps on (micro)plastic pollution by providing a synthesized baseline material for further studies addressing this environmental issue

Pancreatite em adulto com leucemia linfoblástica aguda usando L-asparaginase e sinvastatina: relato de caso e revisão sistemática

Context: Acute pancreatitis is a inflammatory process of the pancreas. It can be caused by gallstones, metabolic disorders, associated or not with alcohol abuse, or medication. Case Report: A 38-year-old man was admitted to the hospital because of worsening of nausea, abdominal pain, dizziness and white stool. Patient was diagnosed with severe acute pancreatitis. After six days of hospitalization, patient progressed into hypotension and severe bradycardia, and died. The patient used simvastatin chronically, and was in treat with L-asparaginase, both drugs related to the occurence of acute pancreatitis separately. Naranjo´s probability scale of adverse drug reaction established the causality between these medications and acute pancreatitis as probable. However, due to the absence of reports of causality, the acute pancreatitis is associated with to the use of L-asparaginase with possible drug interactions with simvastatin. Conclusion: It is very important to monitor patients treated with L-asparaginase, through careful observation of clinical signs and laboratory follow-up, as well as verification of other medications in use. The AP may have different levels of severity, being indispensable the quick diagnosis and early treatmentContexto: Pancreatite aguda é um processo inflamatório do pâncreas. É causada por cálculos biliares, desordens metabólicas, associadas ou não ao uso abusivo de álcool, ou medicamentos. Relato do Caso: Homem de 38 anos foi admitido no hospital em razão do agravamento de náuseas, dor abdominal, tontura e fezes brancas. O paciente foi diagnosticado com pancreatite aguda. Após seis dias de internação, paciente progrediu com hipotensão e bradicardia severa, evoluindo à óbito. O paciente fazia uso crônico de sinvastatina, e estava em tratamento com L-asparaginase, ambos fármacos, de modo separado, são relacionados com a ocorrência de pancreatite aguda severa. O algoritmo de Naranjo para estabelecimento de reação adversa a medicação classificou a causalidade entre as medicações citadas e a pancreatite aguda como provável. Porém, em razão da ausência relatos dessa causalidade, associa-se a pancreatite aguda ao uso de L-asparaginase, com possível interação medicamentosa com sinvastatina. Conclusão: É de suma importância o acompanhamento clínico e laboratorial de pacientes em uso de Lasparaginase para sinais de pancreatite aguda, sendo imprescindível o rápido diagnóstico e tratamento precoc

Stress-induced neuroinflammation: mechanisms and new pharmacological targets

Stress is triggered by numerous unexpected environmental, social or pathological stimuli occurring during the life of animals, including humans, which determine changes in all of their systems. Although acute stress is essential for survival, chronic, long-lasting stress can be detrimental. In this review, we present data supporting the hypothesis that stress-related events are characterized by modifications of oxidative/nitrosative pathways in the brain in response to the activation of inflammatory mediators. Recent findings indicate a key role for nitric oxide (NO) and an excess of pro-oxidants in various brain areas as responsible for both neuronal functional impairment and structural damage. Similarly, cyclooxygenase-2 (COX-2), another known source of oxidants, may account for stress-induced brain damage. Interestingly, some of the COX-2-derived mediators, such as the prostaglandin 15d-PGJ2 and its peroxisome proliferator-activated nuclear receptor PPARγ, are activated in the brain in response to stress, constituting a possible endogenous anti-inflammatory mechanism of defense against excessive inflammation. The stress-induced activation of both biochemical pathways depends on the activation of the N-methyl-D-aspartate (NMDA) glutamate receptor and on the activation of the transcription factor nuclear factor kappa B (NFκB). In the case of inducible NO synthase (iNOS), release of the cytokine TNF-α also accounts for its expression. Different pharmacological strategies directed towards different sites in iNOS or COX-2 pathways have been shown to be neuroprotective in stress-induced brain damage: NMDA receptor blockers, inhibitors of TNF-α activation and release, inhibitors of NFκB, specific inhibitors of iNOS and COX-2 activities and PPARγ agonists. This article reviews recent contributions to this area addressing possible new pharmacological targets for the treatment of stress-induced neuropsychiatric disorders.Spanish Ministries of HealthEducationFAPESPCNP