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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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

Photobromination of indane: preparation of bromoindenones and ready access to benzo[c]fluorenone skeleton

1,1,3,3-Tetrabromoindane and 1,1,2,3,3-pentabromoindane were efficiently synthesized by photolytic bromination of indane. Subsequent dehydrobromination of them gave the corresponding tribromo- and tetrabromoindenes, which were easily converted to the corresponding bromoindenones by silver-supported hydrolysis. Thermolysis of 3-bromoindenone gave the benzo[c]fluorenone derivative

CT features of small bowel obstruction sur to mesodiverticular band

Meckel’s diverticulum is the most common congenital anomaly of the small intestine. Common complications related to a Meckel’s diverticulum include hemorrhage, intestinal obstruction, and inflammation. Small bowel obstruction due to mesodiverticular band of Meckel’s diverticulum is a rare complication. Herein, we report a case of small bowel obstruction occurring due to mesodiverticular band of a Meckel’s diverticulum. The important aspect of our case is clear demonstration of the mesodiverticular band adjacent to the Meckel’s diverticulum on pre-operative computed tomography (CT)

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

Crystal structure of 2,2-exo-3,5,5-exo-6-hexabromobicycloheptane, C7H6Br6

C7H6Br6, monoclinic. P12(1)/n1 (No. 14), a = 7.2717(7) Angstrom, b = 17.152(2) Angstrom, c = 10.0043(7) Angstrom, beta = 97.722(7)degrees V = 1236.5 Angstrom(3), Z = 4, R-gt(F) = 0.086, wR(obs)(F-2)= 0.227, T = 293 K