16 research outputs found

    Practical Investigation of Effectiveness of Direct Solar-Powered Air Heater

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    Solar energy is clean and available, and its use doesn\u27t hurt the environment. Heating conditioned homes and offices in wintertime deduct a large part of the amount of fuel consumed for these purposes. The use of solar radiation to heat the air proved its feasibility and usefulness and is in the research and development process and takes many forms. One of the primary types of solar air heaters is solar air heater of a transparent collector. In this study, a transparent collector solar air heater was designed and manufactured with an area of 1 m2. An aluminum plate was used to be the heating source; it takes its heat from the solar radiation. The tests results confirm the validity of this solar air heater type. The temperature of the heated air increased about 101% of the ambient air. The aluminum plate has proven to work as a source of heat

    Identification of novel bacteriophages with therapeutic potential targeting Enterococcus faecalis

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    The Gram-positive opportunistic pathogen Enterococcus faecalis is frequently responsible for nosocomial infections in humans and represents one of the most common bacteria isolated from recalcitrant endodontic (root canal) infections. E. faecalis is intrinsically resistant to several antibiotics routinely used in clinical settings (such as cephalosporins and aminoglycosides) and can acquire resistance to vancomycin (vancomycin resistant enterococci, VRE). The resistance of E. faecalis to several classes of antibiotics and its capacity to form biofilms cause serious therapeutic problems. In this paper, we report the isolation of several bacteriophages that target E. faecalis strains isolated from the oral cavity of patients suffering root-canal infections. All phages isolated were Siphoviridae with similar tail lengths (200-250 nm) and icosahedral heads. The genome sequences of three isolated phages were highly conserved with the exception of predicted tail protein genes that diverge in sequence, potentially reflecting host range. The properties of the phage with the broadest host-range (SHEF2), was further characterised. We showed that this phage requires interaction with components of the major and variant region Enterococcal polysaccharide antigen (Epa) to engage in lytic infection. Finally, we explored the therapeutic potential of this phage and showed that it can eradicate E. faecalis biofilms formed in vitro on a standard polystyrene surface but also on a cross-sectional tooth-slice model of endodontic infection. We also show that SHEF2 cleared a lethal infection of zebrafish when applied in the circulation. We therefore propose that the phage described in this study could be used to treat a broad range of antibiotic resistant E. faecalis infections

    Langerhan's Cell Histiocytosis Masquerading as Optic Glioma (.pdf)

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    "Langerhans cell histiocytosis (LCH) is a rare disease of uncertain etiology. LCH possibly related to clonal proliferation of CD1a-positive langerhans cells forming a pseudotumoral growth. LCH may present as unifocal, multifocal with a benign or fatal course. LCH disorders are classified into 3 groups: eosinophilic granuloma, Hand-Schüller-Christian disease and Letterer-Siwe disease. The incidence of LCH ranges from 1 to 9 cases per million/ year. Of all cases of LCH, temporal bone involvement has been reported in 20% to 30%. Herein we present an unusual case of LCH masquerading as optic glioma. The clinical, radiological and histopathological results are discussed.

    Vision-Specific Quality of Life in Patients With Post-Acute Sequelae of COVID-19 (PASC)

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    Infection with SARS-CoV-2 (COVID-19) involves multiple systems, including those for vision. People with post-acute sequelae of COVID-19 (PASC) have reported many neurological symptoms such as brain fog, memory difficulties, and headache, as well as vision related complaints. We sought to describe PASC-related visual symptoms in a cohort of non- hospitalized individuals presenting to our outpatient neurology practices and undergoing vision-specific quality of life assessments

    The Quantum Tunneling of Ions Model Can Explain the Pathophysiology of Tinnitus

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    Tinnitus is a well-known pathological entity in clinical practice. However, the pathophysiological mechanisms behind tinnitus seem to be elusive and cannot provide a comprehensive understanding of its pathogenesis and clinical manifestations. Hence, in the present study, we explore the mathematical model of ions’ quantum tunneling to propose an original pathophysiological mechanism for the sensation of tinnitus. The present model focuses on two major aspects: The first aspect is the ability of ions, including sodium, potassium, and calcium, to depolarize the membrane potential of inner hair cells and the neurons of the auditory pathway. This membrane depolarization is induced via the quantum tunneling of ions through closed voltage-gated channels. The state of membrane depolarization can be a state of hyper-excitability or hypo-excitability, depending on the degree of depolarization. Both of these states aid in understanding the pathophysiology of tinnitus. The second aspect is the quantum tunneling signals between the demyelinated neurons of the auditory pathway. These signals are mediated via the quantum tunneling of potassium ions, which exit to the extracellular fluid during an action potential event. These quantum signals can be viewed as a “quantum synapse” between neurons. The formation of quantum synapses results in hyper-excitability among the demyelinated neurons of the auditory pathway. Both of these aspects augment and amplify the electrical signals in the auditory pathway and result in a loss of the spatiotemporal fidelity of sound signals going to the brain centers. The brain interprets this hyper-excitability and loss of spatiotemporal fidelity as tinnitus. Herein, we show mathematically that the quantum tunneling of ions can depolarize the membrane potential of the inner hair cells and neurons of the auditory pathway. Moreover, we calculate the probability of action potential induction in the neurons of the auditory pathway generated by the quantum tunneling signals of potassium ions
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