Search

Communication and public relations practitioners are sometimes criticized for their use of inauthentic strategies. Among them, astroturfing which consists ofsimulating public opinion while keeping one's identity secret. This issue raises ethical questions in democratic societies A scientific literature is developing on the subject.However, it appears that many definitions of the concept of astroturfing coexist, thus; complicating its study. This article proposes a comprehensive definition of astroturfing that overcomes some of the pitfalls identified in a systematic literature review. Based on this definition, a clear typology of astroturfing tactics is then established. Next, a contingency model is proposed to situate communication tactics on a continuum ranging from grassroots to astroturf. This model is,then,illustrated by three case studies. [ABSTRACT FROM AUTHOR]

This paper deals with an adaptive direct torque control of an induction motor fed by a Z-source three-level NPC (Neutral Point Clamped) inverter. The proposed control ensures simultaneously the buck-boost operation mode and the induction motor control. Indeed, a switching table, taking into account the Z-source structure, is developed for the direct torque control. In this context, shoot-through states of the Z-source three-level NPC inverter is applied in each sampling time of the direct torque control. The proposed system can be used as promising solution in event of sags voltage, improve power factor, and reduce harmonics. Experimental tests, carried out on digital development board, clearly demonstrate the feasibility and effectiveness of the proposed control. [ABSTRACT FROM AUTHOR]

This paper deals with the adaptation and implementation of an adaptive direct torque control for the five-leg inverter-dual induction machine drive. The expectations are to take advantage of the direct control benefits, which are: sensorless, ease of implementation, and robustness against parameters variation. The application focuses on an electric vehicle with two driving wheels. For this, both induction motors coupled to the driving wheel are fed through a five-leg power inverter. For that purpose, the structure of this vehicle requires an electric differential, which allows maintaining the stability of the vehicle and especially during cornering. For this, the proposed direct control can ensure the separate control and distribute the required torques to the induction motors. Experiments and simulations are carried out to show that the developed independent control of five-leg inverter is effective and provides a simple configuration with good performance in terms of speed and torque responses. [ABSTRACT FROM AUTHOR]

The conserved Blm10/PA200 proteins are proteasome activators. Previously, we identified PA200-enriched regions in the genome of SH-SY5Y neuroblastoma cells by chromatin immunoprecipitation (ChIP) and ChIP-seq analysis. We also found that selective mitochondrial inhibitors induced PA200 redistribution in the genome. Collectively, our data indicated that PA200 regulates cellular homeostasis at the transcriptional level. In the present study, our aim is to investigate the impact of stable PA200 depletion (shPA200) on the overall transcriptome of SH-SY5Y cells. RNA-seq data analysis reveals that the genetic ablation of PA200 leads to overall changes in the transcriptional landscape of SH-SY5Y neuroblastoma cells. PA200 activates and represses genes regulating metabolic processes, such as the glycolysis and mitochondrial function. Using metabolic assays in live cells, we showed that stable knockdown of PA200 does not change basal respiration. Spare respiratory capacity and proton leak however are slightly, yet significantly, reduced in PA200-deficient cells by 99.834% and 84.147%, respectively, compared to control. Glycolysis and glycolytic capacity show a 42.186% and 26.104% increase in shPA200 cells, respectively, compared to control. These data suggest a shift from oxidative phosphorylation to glycolysis especially when cells are exposed to oligomycin-induced stress. Furthermore, we observed a preserved long and compact tubular mitochondrial morphology after inhibition of ATP synthase by oligomycin, which might be associated with the glycolytic change of shPA200 cells. The present study also demonstrates that the proteolytic cleavage of Opa1 is affected, and that the level of OMA1 is significantly reduced in shPA200 cells upon oligomycin-induced mitochondrial insult. Together, these findings suggest a role for PA200 in the regulation of metabolic changes in response to selective inhibition of ATP synthase in an in vitro cellular model. [ABSTRACT FROM AUTHOR]

Aging is associated with the slowdown of neuronal processing and cognitive performance in the brain; however, the exact cellular mechanisms behind this deterioration in humans are poorly elucidated. Recordings in human acute brain slices prepared from tissue resected during brain surgery enable the investigation of neuronal changes with age. Although neocortical fast-spiking cells are widely implicated in neuronal network activities underlying cognitive processes, they are vulnerable to neurodegeneration. Herein, we analyzed the electrical properties of 147 fast-spiking interneurons in neocortex samples resected in brain surgery from 106 patients aged 11–84 years. By studying the electrophysiological features of action potentials and passive membrane properties, we report that action potential overshoot significantly decreases and spike half-width increases with age. Moreover, the action potential maximum-rise speed (but not the repolarization speed or the afterhyperpolarization amplitude) significantly changed with age, suggesting a particular weakening of the sodium channel current generated in the soma. Cell passive membrane properties measured as the input resistance, membrane time constant, and cell capacitance remained unaffected by senescence. Thus, we conclude that the action potential in fast-spiking interneurons shows a significant weakening in the human neocortex with age. This may contribute to the deterioration of cortical functions by aging. • Recordings in human acute brain slices prepared from tissue resected during brain surgery enable investigating neuronal changes with age. • Action potential in fast-spiking interneurons shows a significant weakening in the human neocortex with age. • Neuron intrinsic excitability, measured as the input resistance, membrane time constant, and cell capacitance remained unaffected by senescence. • These changes in neurons' electrical activity may contribute to the deterioration of cortical functions with age. [ABSTRACT FROM AUTHOR]

Adnexal carcinomas are rare, accounting for less than 1% of skin carcinomas. Sclerosus carcinoma of the sweat glands was first described by Goldstein et al. in 1982. We here report the case of a 33-year-old female patient with a retracted perianal skin lesion. Histological examination of perilesional skin biopsy, immunohistochemistry, and negative results of laboratory tests, radiological and endoscopic investigations allowed for the diagnosis of eccrine sclerosus carcinoma. This is a rare tumor, usually characterized by facial localization and slow but aggressive progression. It poses problems in differential diagnosis with benign and malignant tumors; hence the challenge encountered by pathologist of suspecting this carcinoma in patients with any sclerotic and infiltrating skin lesion characterized by slow progression, in a context of preservation of the general state and in the absence of neoplastic history as well as of feeling free to ask for new deep biopsies when in doubt. [ABSTRACT FROM AUTHOR]

Summary: This paper deals with a direct torque control for nine switches inverter fed two induction motors‐based electric vehicles (EVs). In EVs application, the developed system will decrease the installation cost and weight (power electronic devices, position sensors, and mechanical differential). In this context, an adaptive direct torque control of nine switches Inverter which feeds two induction motors is proposed in order to ensure a separate control of two driving wheels and stability for the vehicle when cornering or under slippery road conditions. The experimental tests using dSPACE 1104 card are carried‐out to demonstrate the feasibility and effectiveness of the proposed control solution, in terms of robustness and stability. [ABSTRACT FROM AUTHOR]

Schwannomas of the descending loop of the hypoglossal nerve are very rare. Existing literature of the schwannoma of the descending loop of the hypoglossal nerve is limited to two previously reported case. They are slow-growing tumors that may masquerade a carotid body tumor. We herein described a rare case of schwannoma of the descending loop of the hypoglossal nerve in the s right latero-cervical region with diagnostic imaging and histopathological findings. A 37-years-old woman has had a palpable firm, mobile mass in the right latero-cervical region, of imaging, MR images showed homogeneous hypointensity on T1-weighted imaging (T1-WI), heterogeneous hyperintensity on T2-WI, and heterogeneous enhancement on contrast-enhanced T1-WI. Diagnostic imaging using computed tomography (CT) and magnetic resonance imaging (MRI) was suspected of Chemodectoma or neurogenic tumor. At operation, a 4 cm mass arising from the descending loop of the hypoglossal nerve of was resected en bloc with the loop itself; Final diagnosis was confirmed on the basis of histopathological finding and intraoperative findings. Postoperative course was uneventful and the patient is free from disease recurrence at tree-year follow-up. En bloc resection remains the real curative treatment of Schwannomas, ensuring unlimited freedom from disease, although causing functional impairment which may be significant. Nonetheless recurrence should be prevented as, besides requiring reintervention, it may harbor a malignant evolution towards sarcoma. Schwannomas of the descending loop of the hypoglossal nerve may masquerade a chemodectoma of the carotid bifurcation and can be curatively resected without any functional impairment. This case confirmed the differential diagnosis on the basis of the intraoperative finding that the tumor was continuous with the hypoglossal nerve. [ABSTRACT FROM AUTHOR]