A simple solution of sound transmission through an elastic wall to a rectangular enclosure, including wall damping and air viscosity effects

A simple solution to the problem of the acoustical coupling between a rectangular structure, its air content, and an external noise source is presented. This solution is a mathematical expression for the normalized acoustic pressure inside the structure. Numerical results for the sound-pressure response for a specified set of parameters are also presented

Dengue virus infection changes Aedes aegypti oviposition olfactory preferences

Aedes aegypti mosquitoes, main vectors for numerous flaviviruses, have olfactory preferences and are capable of olfactory learning especially when seeking their required environmental conditions to lay their eggs. In this study, we showed that semiochemical conditions during Aedes aegypti larval rearing affected future female choice for oviposition: water-reared mosquitoes preferred to lay eggs in water or p-cresol containers, while skatole reared mosquitoes preferred skatole sites. Using two independent behavioural assays, we showed that this skatole preference was lost in mosquitoes infected with dengue virus. Viral RNA was extracted from infected female mosquito heads, and an increase of virus load was detected from 3 to 10 days post infection, indicating replication in the insect head and possibly in the central nervous system. Expression of selected genes, potentially implied in olfactory learning processes, were also altered during dengue infection. Based on these results, we hypothesise that dengue virus infection alters gene expression in the mosquito\u27s head and is associated with a loss of olfactory preferences, possibly modifying oviposition site choice of female mosquitoes

A case report of complete resolution of nonimmunological hydrops fetalis without known etiology

The prevalence of nonimmunological hydrops fetalis has been reported between 1 in 1500 and 1 in 4000, with an approximate 80 mortality rate. This case-report study explains a case of hydrops fetalis, presented with generalized edema and pleural and pericardial effusion at 30 weeks of gestation with preterm birth at this age due to preterm uterine contractions. No etiology was found for hydrops and all signs resolved thoroughly after birth without treatment. After birth, the newborn was admitted to neonatal intensive care unit and discharged after 47 days in good condition. The infant was completely healthy within three months after delivery. © 2021

Electrophysiological evidence of RML12 mosquito cell line towards neuronal differentiation by 20-hydroxyecdysdone

Continuous cell lines from insect larval tissues are widely used in different research domains, such as virology, insect immunity, gene expression, and bio pharmacology. Previous study showed that introduction of 20-hydroxyecdysone to Spodoptera cell line induced a neuron-like morphology with neurite extensions. Despite some results suggesting potential presence of neuro-receptors, no study so far has shown that these neuron-induced cells were functional. Here, using microelectrode arrays, we showed that the mosquito cell line, RML12, differentiated with 20-hydroxyecdysone, displays spontaneous electrophysiological activity. Results showed that these cells can be stimulated by GABAergic antagonist as well as nicotinic agonist. These results provide new evidence of neuron-like functionality of 20-hydroxyecdysone induced differentiated mosquito cell line. Finally, we used this new model to test the effects of two insecticides, temephos and permethrin. Our analysis revealed significant changes in the spiking activity after the introduction of these insecticides with prolonged effect on the neuronal activity. We believe that this differentiated mosquito neuronal cell model can be used for high-throughput screening of new pesticides on insect nervous system instead of primary neurons or in vivo studies

Prediction of residual stresses in roller burnished components : a finite element approach

Surface finish is an important factor in creating the durable metal components, and fatigue strength can be improved if compressive residual stresses are produced in the surface. Burnishing is a finishing process and compressive residual stresses are induced during the process. The present study of minimizing the surface roughness based on the experimental work, and finite element model was developed to evaluate the analytical results. Commercial purity Mild Steel and Aluminium were selected as work specimens and a high carbon high chromium roller was used as a tool for the burnishing process.<br /

The choice of insider or outsider top executives in acquired companies

There is considerable debate amongst academics and practitioners over whether top executives of acquired or merged companies should stay or go, post-deal, as studies exploring the link with organisational performance show mixed results. This may in part be due to such studies failing to recognise that there are a number of distinct post-acquisition strategies which may require the deployment of different types of top executive. This paper addresses this limitation by bringing together the longstanding Insider/Outsider debate with a post-acquisition integration framework, in order to investigate whether there is a link between top management type and post-acquisition integration strategy. Using a dual methodology of survey and cases drawing on UK M&A data, clear associations are found between top executive type and particular post-acquisition styles. Underlying these patterns, the value-creating/value-capturing distinction of the Resource-Based View appears to have a greater influence over top executive deployment than do issues of Organisational Fit. This suggests strategic intentions have ascendancy over organisational constraints in the selection of top executives for managing post-acquisition integration

Neurotropism and behavioral changes associated with Zika infection in the vector Aedes aegypti

Understanding Zika virus infection dynamics is essential, as its recent emergence revealed possible devastating neuropathologies in humans, thus causing a major threat to public health worldwide. Recent research allowed breakthrough in our understanding of the virus and host pathogenesis; however, little is known on its impact on its main vector, Aedes aegypti. Here we show how Zika virus targets Aedes aegypti&rsquo;s neurons and induces changes in its behavior. Results are compared to dengue virus, another flavivirus, which triggers a different pattern of behavioral changes. We used microelectrode array technology to record electrical spiking activity of mosquito primary neurons post infections and discovered that only Zika virus causes an increase in spiking activity of the neuronal network. Confocal microscopy also revealed an increase in synapse connections for Zika virus-infected neuronal networks. Interestingly, the results also showed that mosquito responds to infection by overexpressing glutamate regulatory genes while maintaining virus levels. This neuro-excitation, possibly via glutamate, could contribute to the observed behavioral changes in Zika virus-infected Aedes aegypti females. This study reveals the importance of virus-vector interaction in arbovirus neurotropism, in humans and vector. However, it appears that the consequences differ in the two hosts, with neuropathology in human host, while behavioral changes in the mosquito vector that may be advantageous to the virus

Risk factors prediction, clinical outcomes, and mortality in COVID-19 patients

Preventing communicable diseases requires understanding the spread, epidemiology, clinical features, progression, and prognosis of the disease. Early identification of risk factors and clinical outcomes might help in identifying critically ill patients, providing appropriate treatment, and preventing mortality. We conducted a prospective study in patients with flu-like symptoms referred to the imaging department of a tertiary hospital in Iran between March 3, 2020, and April 8, 2020. Patients with COVID-19 were followed up after two months to check their health condition. The categorical data between groups were analyzed by Fisher's exact test and continuous data by Wilcoxon rank-sum test. Three hundred and nineteen patients (mean age 45.48 ± 18.50 years, 177 women) were enrolled. Fever, dyspnea, weakness, shivering, C-reactive protein, fatigue, dry cough, anorexia, anosmia, ageusia, dizziness, sweating, and age were the most important symptoms of COVID-19 infection. Traveling in the past 3 months, asthma, taking corticosteroids, liver disease, rheumatological disease, cough with sputum, eczema, conjunctivitis, tobacco use, and chest pain did not show any relationship with COVID-19. To the best of our knowledge, a number of factors associated with mortality due to COVID-19 have been investigated for the first time in this study. Our results might be helpful in early prediction and risk reduction of mortality in patients infected with COVID-19. © 2020 Wiley Periodicals LL