Forced Convection Heat Transfer from a Finite-Height Cylinder

[EN] This paper presents a large eddy simulation of forced convection heat transfer in the flow around a surface-mounted finite-height circular cylinder. The study was carried out for a cylinder with height-to-diameter ratio of 2.5, a Reynolds number based on the cylinder diameter of 44 000 and a Prandtl number of 1. Only the surface of the cylinder is heated while the bottom wall and the inflow are kept at a lower fixed temperature. The approach flow boundary layer had a thickness of about 10% of the cylinder height. Local and averaged heat transfer coefficients are presented. The heat transfer coefficient is strongly affected by the free-end of the cylinder. As a result of the flow over the top being downwashed behind the cylinder, a vortex-shedding process does not occur in the upper part, leading to a lower value of the local heat transfer coefficient in that region. In the lower region, vortex-shedding takes place leading to higher values of the local heat transfer coefficient. The circumferentially averaged heat transfer coefficient is 20 % higher near the ground than near the top of the cylinder. The spreading and dilution of the mean temperature field in the wake of the cylinder are also discussed.The simulation was carried out using the supercomputing facilities of the Steinbuch Centre for Computing (SCC) of the Karlsruhe Institute of Technology. MGV has been partially supported by grant TRA2012-37714 of the Spanish Ministry of Economy and Competitiveness.García Villalba, M.; Palau-Salvador, G.; Rodi, W. (2014). Forced Convection Heat Transfer from a Finite-Height Cylinder. Flow, Turbulence and Combustion. 93(1):171-187. https://doi.org/10.1007/s10494-014-9543-7S171187931Ames, F., Dvorak, L.: Turbulent transport in pin fin arrays: experimental data and predictions. J. Turbomach. 128(1), 71–81 (2006)Armstrong, J., Winstanley, D.: A review of staggered array pin fin heat transfer for turbine cooling applications. J. 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Procyanidins are potent inhibitors of LOX-1: a new player in the French Paradox

Lectin-like oxidized LDL receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL (oxLDL) and plays multiple roles in the development of cardiovascular diseases. We screened more than 400 foodstuff extracts for identifying materials that inhibit oxLDL binding to LOX-1. Results showed that 52 extracts inhibited LOX-1 by more than 70% in cell-free assays. Subsequent cell-based assays revealed that a variety of foodstuffs known to be rich in procyanidins such as grape seed extracts and apple polyphenols, potently inhibited oxLDL uptake in Chinese hamster ovary (CHO) cells expressing LOX-1. Indeed, purified procyanidins significantly inhibited oxLDL binding to LOX-1 while other ingredients of apple polyphenols did not. Moreover, chronic administration of oligomeric procyanidins suppressed lipid accumulation in vascular wall in hypertensive rats fed with high fat diet. These results suggest that procyanidins are LOX-1 inhibitors and LOX-1 inhibition might be a possible underlying mechanism of the well-known vascular protective effects of red wine, the French Paradox

Function of SSA Subfamily of Hsp70 Within and Across Species Varies Widely in Complementing Saccharomyces cerevisiae Cell Growth and Prion Propagation

BACKGROUND:The cytosol of most eukaryotic cells contains multiple highly conserved Hsp70 orthologs that differ mainly by their spatio-temporal expression patterns. Hsp70s play essential roles in protein folding, transport or degradation, and are major players of cellular quality control processes. However, while several reports suggest that specialized functions of Hsp70 orthologs were selected through evolution, few studies addressed systematically this issue. METHODOLOGY/PRINCIPAL FINDINGS:We compared the ability of Ssa1p-Ssa4p from Saccharomyces cerevisiae and Ssa5p-Ssa8p from the evolutionary distant yeast Yarrowia lipolytica to perform Hsp70-dependent tasks when expressed as the sole Hsp70 for S. cerevisiae in vivo. We show that Hsp70 isoforms (i) supported yeast viability yet with markedly different growth rates, (ii) influenced the propagation and stability of the [PSI(+)] and [URE3] prions, but iii) did not significantly affect the proteasomal degradation rate of CFTR. Additionally, we show that individual Hsp70 orthologs did not induce the formation of different prion strains, but rather influenced the aggregation properties of Sup35 in vivo. Finally, we show that [URE3] curing by the overexpression of Ydj1p is Hsp70-isoform dependent. CONCLUSION/SIGNIFICANCE:Despite very high homology and overlapping functions, the different Hsp70 orthologs have evolved to possess distinct activities that are required to cope with different types of substrates or stress situations. Yeast prions provide a very sensitive model to uncover this functional specialization and to explore the intricate network of chaperone/co-chaperone/substrates interactions

Theories of schizophrenia: a genetic-inflammatory-vascular synthesis

BACKGROUND: Schizophrenia, a relatively common psychiatric syndrome, affects virtually all brain functions yet has eluded explanation for more than 100 years. Whether by developmental and/or degenerative processes, abnormalities of neurons and their synaptic connections have been the recent focus of attention. However, our inability to fathom the pathophysiology of schizophrenia forces us to challenge our theoretical models and beliefs. A search for a more satisfying model to explain aspects of schizophrenia uncovers clues pointing to genetically mediated CNS microvascular inflammatory disease. DISCUSSION: A vascular component to a theory of schizophrenia posits that the physiologic abnormalities leading to illness involve disruption of the exquisitely precise regulation of the delivery of energy and oxygen required for normal brain function. The theory further proposes that abnormalities of CNS metabolism arise because genetically modulated inflammatory reactions damage the microvascular system of the brain in reaction to environmental agents, including infections, hypoxia, and physical trauma. Damage may accumulate with repeated exposure to triggering agents resulting in exacerbation and deterioration, or healing with their removal. There are clear examples of genetic polymorphisms in inflammatory regulators leading to exaggerated inflammatory responses. There is also ample evidence that inflammatory vascular disease of the brain can lead to psychosis, often waxing and waning, and exhibiting a fluctuating course, as seen in schizophrenia. Disturbances of CNS blood flow have repeatedly been observed in people with schizophrenia using old and new technologies. To account for the myriad of behavioral and other curious findings in schizophrenia such as minor physical anomalies, or reported decreased rates of rheumatoid arthritis and highly visible nail fold capillaries, we would have to evoke a process that is systemic such as the vascular and immune/inflammatory systems. SUMMARY: A vascular-inflammatory theory of schizophrenia brings together environmental and genetic factors in a way that can explain the diversity of symptoms and outcomes observed. If these ideas are confirmed, they would lead in new directions for treatments or preventions by avoiding inducers of inflammation or by way of inflammatory modulating agents, thus preventing exaggerated inflammation and consequent triggering of a psychotic episode in genetically predisposed persons

Управління інноваціями в освіті: рівень задоволеності студентів та їх працевлаштування

Open and distance education, unlike the traditional style of education, does not have to come to the campus, courses are processed in a completely virtual environment through the computer, live and interactive is the name of the training that the participant can watch them again and again at any time. Open and distance education in this aspect; Student Centre is an ideal educational model for people who cannot benefit from traditional education, providing equal opportunities, providing education opportunities for physically disabled students, eliminating geographical and regional barriers. Besides, it is a modern and innovative education model that ensures the continuation of the education of the people working in their businesses. Career compliance is a process that starts from preparation for the profession and starts from employment, progress in career and ending a career. Career compliance reflects an individual’s capacity to cope with potential changes that may arise in the present and future business life. Besides, employees’ level of coping with new job responsibilities, unexpected career changes and the ability to overcome obstacles that may arise. The main purpose of this study is to examine the relationship between education satisfaction levels and career adaptability perceptions of participants taking education within open or distance education model. The study is important in terms of developing and improving the open or distance education model when considering that the number of people taking education within the open or distance education model in our country is more than three and a half million today. Besides, one of the important issues in working life in contemporary societies is the career issue and it is thought that the adaptability of employees with their occupations has an important role in their productivity. Therefore, determining the level of educational satisfaction and career adaptability is thought to be important. In the study, which is based on «lifelong learning theory», the quantitative research method was preferred. To collect data, the «Distance Education Satisfaction Scale» and the «Career-related Adoptability» scales were employed. Data collected from a sample of 527 individuals were analysed by difference, relationship and impact tests and it was found that distance education satisfaction had a positive effect on career adaptability.Особливість онлайн та дистанційної форми навчання, на відміну від традиційної форми, полягає у відсутності необхідності безпосередньої присутності у навчальній аудиторії, так як навчання відбувається у віртуальному середовищі з використанням інформаційних технологій. При цьому, як правило, застосовуються інтерактивні методи навчання, що у свою чергу дають можливість студентам користуватись навчальним матеріалом в будь-який час. У статті визначено, що онлайн та дистанційна форма навчання є ідеальною освітньою моделлю для тих, хто не може скористатися традиційною моделлю, надаючи рівні можливості для осіб з обмеженими можливостями, а також усуваючи географічні та регіональні бар'єри. Крім того, це сучасна та інноваційна модель освіти, яка забезпечує продовження навчання у продовж життя. Авторами зазначено, що сучасні тренди світового розвитку провокують зміну парадигми і вимог до навичок та знань як випускників, так і працівників. Нові тенденції обумовлюють необхідність постійного навчання на всіх етапах: підготовка до працевлаштування, кар’єрне зростання та завершення кар’єри. У цьому аспекті, невід’ємною вимогою успішного кар’єрного зростання є здатність працівників швидко адаптуватись до нових вимог. Основною метою статті є аналіз взаємозв'язків між рівнями задоволеності освітою та відповідності до кар'єрних вимог осіб, які отримують освіту в рамках онлайн або дистанційної моделі навчання. Авторами зазначено, що актуальність дослідження обумовлена необхідністю вдосконаленням онлайн та дистанційної форми навчання. Визначено, що кількість осіб, які отримують освіту в рамках даної форми навчання в Туреччині становить більше трьох з половиною мільйонів. У статті висунуто гіпотезу про позитивний вплив рівня задоволеності дистанційною освітою на відповідність кар’єрним вимогам. Дані для аналізу згенеровано на основі результатів опитування 527 респондентів. У статті використано тести на перевірку різниць, взаємозв'язків та взаємовпливів між визначеними змінними. Емпіричні результати підтвердили гіпотезу, що рівень задоволеності навчанням має статистично значущий позитивний вплив на рівень відповідності кар’єрним вимогам

Osteochondroma of the nasal dorsum presenting as a nasal hump

We describe the case of a 24-year-old man who underwent open septorhinoplasty for the treatment of progressive nasal disfigurement caused by a nasal hump. Postoperative histopathology of the resected hump revealed that it was an osteochondroma. The patient showed no evidence of recurrence during 2 years of follow-up. To the best of our knowledge, this is the first case of an osteochondroma involving the nasal dorsum to be reported in the English-language literature. © 2014 Vendome Group