Bioinspired snapping-claw apparatus to study hydrodynamic cavitation effects on the corrosion of metallic samples

A creative low-cost and compact mechanical device that mimics the rapid closure of the pistol shrimp claw was used to conduct electrochemical experiments, in order to study the effects of hydrodynamic cavitation on the corrosion of aluminum and steel samples. Current-time curves show significant changes associated with local variations in dissolved O2 concentration, cavitation-induced erosion and changes in the nature of the surface corrosion products

Четыре радиоиндуцированные злокачественные опухоли, ишемическая болезнь сердца, атеросклероз и констриктивный перикардит у больной с лимфомой Ходжкина, получавшей лучевую терапию: клинический случай

Introduction. Radiation therapy (RT) has been widely used since the 1970s in the treatment of Hodgkin’s lymphoma. RT increases the risk of secondary malignancies and heart disease including coronary artery disease, noncoronary atherosclerotic valvular disease, valvular dysfunction, pericardial disease and radiation induced vasculopathy.Case Presentation. We describe a case of a patient with 4 secondary malignancies due to previous RT including parotid mucoepidermoid carcinoma, breast multicentric infiltrating ducta, thyroid papillary microcarcinoma with follicular pattern and lung adenocarcinoma that later presented with severe constrictive pericarditis, which led to an emergency pericardiectomy – all of these were complications of her previous radiotherapy. She received a prompt diagnosis and treatment.\Discussion. Radiation-induced vascular disease (RIVD) occurs due to endothelial injury following RT; patients have up to 3–4 fold increase in risk of myocardial infarction due to CAD, therefore screening of CAD with a CT coronary angiography is recommended to begin 5 years after receiving RT in patients 45 and older and 10 years after RT in patients <45 years old. Radiation induced secondary malignancies (RISM) are seen in 17–19 % of cases and the risk increases by time since last RT session. Many factors contribute to the risk severity of developing RISM such as age of radiation, dosage and size of the area irradiated, and radiation technique. Lung and breast cancer are the most common forms of second malignancy. A prompt screening, diagnosis and treatment of the RT complications are vital and should be prioritized in every control.Актуальность. Лучевая терапия (ЛТ) для лечения лимфомы Ходжкина широко используется с 1970-х гг. ЛТ увеличивает риск развития злокачественных новообразований и заболеваний сердца, включая ишемическую болезнь сердца, некоронарное атеросклеротическое поражение клапанов, дисфункцию клапанов, заболевание перикарда и васкулопатию, индуцированную лучевой терапией.Описание клинического случая. Представлен клинический случай пациентки с 4 злокачественными новообразованиями, возникшими вследствие ЛТ: мукоэпидермоидная карцинома околоушной слюнной железы, мультицентрический инфильтрирующий протоковый рак молочной железы, папиллярная микрокарцинома щитовидной железы с фолликулярным вариантом и аденокарцинома легкого, с разитием последующего тяжелого констриктивного перикардита, что привело к экстренной перикардэктомии. Все эти осложнения были результатом предыдущей лучевой терапии по поводу лимфомы Ходжкина. Пациентка получила своевременную диагностику и лечение.Обсуждение. Радиоиндуцированные сердечно-сосудистые заболевания возникают из-за повреждения эндотелия после лучевой терапии. У пациентов с ИБС риск развития инфаркта миокарда повышается в 3–4 раза, поэтому скрининг ИБС с помощью КТ-коронарографии рекомендуется начинать через 5 лет после ЛТ у пациентов в возрасте 45 лет и старше и через 10 лет после ЛТ у пациентов в возрасте <45 лет. Развитие радиоиндуцированных злокачественных новообразований наблюдается в 17–19 % случаев; риск их развития растет с увеличением времени, прошедшего после завершения лучевой терапии. Многие факторы влияют на риск возникновения злокачественных опухолей: возраст, доза, размер полей и метод облучения. Рак легкого и рак молочной железы являются наиболее частыми локализациями радиоиндуцированных новообразований. Своевременная диагностика и лечение осложнений ЛТ должны быть приоритетом при контрольном обследовании

Bose-Einstein condensate dark matter phase transition from finite temperature symmetry breaking of Klein-Gordon fields

In this paper the thermal evolution of scalar field dark matter particles at finite cosmological temperatures is studied. Starting with a real scalar field in a thermal bath and using the one loop quantum corrections potential, we rewrite Klein-Gordon's (KG) equation in its hydrodynamical representation and study the phase transition of this scalar field due to a Z_2 symmetry breaking of its potential. A very general version of a nonlinear Schr\"odinger equation is obtained. When introducing Madelung's representation, the continuity and momentum equations for a non-ideal SFDM fluid are formulated, and the cosmological scenario with the SFDM described in analogy to an imperfect fluid is then considered where dissipative contributions are obtained in a natural way.Additional terms appear compared to those obtained in the classical version commonly used to describe the \LambdaCDM model, i.e., the ideal fluid. The equations and parameters that characterize the physical properties of the system such as its energy, momentum and viscous flow are related to the temperature of the system, scale factor, Hubble's expansion parameter and the matter energy density. Finally, some details on how galaxy halos and smaller structures might be able to form by condensation of this SF are given.Comment: Substantial changes have been made to the paper, following the referees recommendations. 16 pages. Published in Classical and Quantum Gravit

Co-phasing the Large Binocular Telescope: status and performance of LBTI/PHASECam

The Large Binocular Telescope Interferometer is a NASA-funded nulling and imaging instrument designed to coherently combine the two 8.4-m primary mirrors of the LBT for high-sensitivity, high-contrast, and high-resolution infrared imaging (1.5-13 um). PHASECam is LBTI's near-infrared camera used to measure tip-tilt and phase variations between the two AO-corrected apertures and provide high-angular resolution observations. We report on the status of the system and describe its on-sky performance measured during the first semester of 2014. With a spatial resolution equivalent to that of a 22.8-meter telescope and the light-gathering power of single 11.8-meter mirror, the co-phased LBT can be considered to be a forerunner of the next-generation extremely large telescopes (ELT).Comment: 8 pages, 5 figures, SPIE Conference proceeding

A Role for the Cannabinoid 1 Receptor in Neuronal Differentiation of Adult Spinal Cord Progenitors in vitro is Revealed through Pharmacological Inhibition and Genetic Deletion

In contrast to the adult brain, the adult spinal cord is a non-neurogenic environment. Understanding how to manipulate the spinal cord environment to promote the formation of new neurons is an attractive therapeutic strategy for spinal cord injury and disease. The cannabinoid 1 receptor (CB1R) has been implicated as a modulator of neural progenitor cell proliferation and fate specification in the brain; however, no evidence exists for modulation of adult spinal cord progenitor cells. Using adult rat spinal cord primary cultures, we demonstrated that CB1R antagonism with AM251 significantly decreased the number of Nestin(+) cells, and increased the number of βIII tubulin(+) and DCX(+) cells, indicative of neuronal differentiation. AM251’s effect was blocked by co-application of the CB1R agonists, WIN 55, 212-2, or ACEA. Consistent with our hypothesis, cultures, and spinal cord slices derived from CB1R knock-out (CB1−/−) mice had significantly higher levels of DCX(+) cells compared to those derived from wild type (CB1+/+) mice, indicative of enhanced neuronal differentiation in CB1−/− spinal cords. Moreover, AM251 promoted neuronal differentiation in CB1+/+, but not in CB1−/− cultures. Since CB1R modulates synaptic transmission, and synaptic transmission has been shown to influence progenitor cell fate, we evaluated whether AM251-induced neuronal differentiation was affected by chronic inactivity. Either the presence of the voltage-dependent sodium channel blocker tetrodotoxin (TTX), or the removal of mature neurons, inhibited the AM251-induced increase in DCX(+) cells. In summary, antagonism or absence of CB1R promotes neuronal differentiation in adult spinal cords, and this action appears to require TTX-sensitive neuronal activity. Our data suggest that the previously detected elevated levels of endocannabinoids in the injured adult spinal cord could contribute to the non-neurogenic environment and CB1R antagonists could potentially be used to enhance replacement of damaged neurons

Exoplanet science with the LBTI: instrument status and plans

The Large Binocular Telescope Interferometer (LBTI) is a strategic instrument of the LBT designed for high-sensitivity, high-contrast, and high-resolution infrared (1.5-13 $\mu$m) imaging of nearby planetary systems. To carry out a wide range of high-spatial resolution observations, it can combine the two AO-corrected 8.4-m apertures of the LBT in various ways including direct (non-interferometric) imaging, coronagraphy (APP and AGPM), Fizeau imaging, non-redundant aperture masking, and nulling interferometry. It also has broadband, narrowband, and spectrally dispersed capabilities. In this paper, we review the performance of these modes in terms of exoplanet science capabilities and describe recent instrumental milestones such as first-light Fizeau images (with the angular resolution of an equivalent 22.8-m telescope) and deep interferometric nulling observations.Comment: 12 pages, 6 figures, Proc. SPI

Determining science teachers’ ideas about the science process skills: a case study

AbstractThe aim of this study is to investigate science teachers’ ideas about the science process skills (SPS) using qualitative analysis. This study was carried out at the first term of 2008- 2009 academic year. A case study research methodology was used. The sample of this study consisted of 10 science teachers (ST), who has been working at Giresun center elementary schools in Turkey. A semi-structured interview procedure was used to collect data. The collected data were analyzed with Nvivo 8 program. The results indicate that the majority of sample have not had widespread theoretical knowledge on SPS