618,617 research outputs found

    Combined Diffusion-Relaxometry MRI to Identify Dysfunction in the Human Placenta

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    Purpose: A combined diffusion-relaxometry MR acquisition and analysis pipeline for in-vivo human placenta, which allows for exploration of coupling between T2* and apparent diffusion coefficient (ADC) measurements in a sub 10 minute scan time. Methods: We present a novel acquisition combining a diffusion prepared spin-echo with subsequent gradient echoes. The placentas of 17 pregnant women were scanned in-vivo, including both healthy controls and participants with various pregnancy complications. We estimate the joint T2*-ADC spectra using an inverse Laplace transform. Results: T2*-ADC spectra demonstrate clear quantitative separation between normal and dysfunctional placentas. Conclusions: Combined T2*-diffusivity MRI is promising for assessing fetal and maternal health during pregnancy. The T2*-ADC spectrum potentially provides additional information on tissue microstructure, compared to measuring these two contrasts separately. The presented method is immediately applicable to the study of other organs

    Determination of the suitable drilling operating parameters in different geological formations El-Sharara Oil Field (South-Western Libya)

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    Purpose. The objective of this study is to determine the best operating conditions for the most notable drilling parameters (i.e. weight on bit (WOB), rotary drilling speed (RPM), and characteristics of drilling fluid) using field data obtained from El-Sharara Oil Field. Methods. The used data has been extracted from daily drilling reports of well named (NC-186/K04h) field. Such data contains information about the geological formations, casing strings, drill-bits, fuel consumption, flow rate of drilling fluid and other drilling parameters. Findings. The results reveal that, the lower geological formations of El-Sharara Oil Field, the harder are the upper formations. Therefore, it is recommended to apply heavy loads (i.e. WOB of 45000 lb) with low drilling speed (i.e. 100 rpm) in the lower formations; and to apply small loads (i.e. WOB of 19000 lb) with high drilling speed (i.e. 160 rpm) in the upper formations. Originality. This study evaluates the performance of drilling operation based on the interaction between rock formations and machine drilling parameters. Practical implications. Understanding such interaction between rock formations and machine drilling parameters will remarkably improve the rate of penetration (ROP) in the related geological formations. Consequently, the overall drilling costs will be reduced in terms of drilling time, life of drill-bit and fuel consumption.Мета. Визначення оптимальних експлуатаційних умов для технологічних параметрів буріння – осьового навантаження на долото (ОНД), швидкості обертального буріння (ШOБ), характеристик бурового розчину на основі емпіричних даних, отриманих на нафтовому родовищі Ель-Шарара. Методика. У роботі вивчені та систематизовані дані експлуатації нафтової свердловини NC-186/K04h, що містять інформацію про геологічні формації родовища, обсадних колонах, бурових коронках, витрат палива і бурової рідини та інших параметрах буріння. Результати. Дослідження показало, що, чим нижче розташовані нафтоносні геологічні формації Ель-Шарара, тим міцніше породи верхніх формацій. Рекомендовано застосовувати велике навантаження (ОНД – близько 104 кг), при низькій ШOБ (100 об/хв) у нижніх формаціях; і мале навантаження (ОНД – 86 кг) при високій ШOБ (160 об/хв) – у верхніх формаціях. Встановлено кореляційний взаємозв’язок комплексу технологічних параметрів буріння з умовами геологічних формацій родовища. Наукова новизна. Для умов нафтового родовища Ель-Шарара дана наукова оцінка ефективності буріння на основі встановлення взаємозв’язку параметрів формацій і бурових установок. Практична значимість. Врахування взаємозв’язку геологічних формацій і параметрів механічного буріння дозволить суттєво підвищити швидкість проходки свердловин, при цьому загальні витрати на буріння будуть скорочені за рахунок зменшення часу буріння, споживання палива та збільшення терміну служби бурових коронок.Цель. Определение оптимальных эксплуатационных условий для технологических параметров бурения – осевой нагрузки на долото (ОНД), скорости вращательного бурения (СВБ), характеристик бурового раствора на основе эмпирических данных, полученных на нефтяном месторождении Эль-Шарара. Методика. В работе изучены и систематизированы данные о эксплуатации нефтяной скважины NC-186/K04h, которые содержат информацию о геологических формациях месторождения, обсадных колоннах, буровых коронках, расходе топлива и буровой жидкости, а также других параметрах бурения. Результаты. Исследование показало, что, чем ниже расположены нефтеносные геологические формации Эль-Шарара, тем тверже породы верхних формаций. Рекомендуется применять большую нагрузку (ОНД – около 104 кг), при низкой СВБ (100 вр/мин) в нижних формациях; и малую нагрузку (ОНД – 86 кг) при высокой СВБ (160 вр/мин) – в верхних формациях. Установлена корреляционная взаимосвязь комплекса технологических параметров бурения с условиями геологических формаций месторождения. Научная новизна. Для условий нефтяного месторождения Эль-Шарара дана научная оценка эффективности бурения на основе установления взаимосвязи параметров формаций и буровых установок. Практическая значимость. Учет взаимосвязи геологических формаций и параметров механического бурения позволит существенно увеличить скорость проходки скважин, при этом общие затраты на бурение будут сокращены за счет уменьшения времени бурения, потребления топлива и увеличения срока службы буровых коронок.The authors declare that the paper has not been originated under any project and no funding has been raised for this research

    The role of human body movements in mate selection

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    It is common scientific knowledge, that most of what we say within a conversation is not only expressed by the words meaning alone, but also through our gestures, postures, and body movements. This non-verbal mode is possibly rooted firmly in our human evolutionary heritage, and as such, some scientists argue that it serves as a fundamental assessment and expression tool for our inner qualities. Studies of nonverbal communication have established that a universal, culture-free, non-verbal sign system exists, that is available to all individuals for negotiating social encounters. Thus, it is not only the kind of gestures and expressions humans use in social communication, but also the way these movements are performed, as this seems to convey key information about an individuals quality. Dance, for example, is a special form of movement, which can be observed in human courtship displays. Recent research suggests that people are sensitive to the variation in dance movements, and that dance performance provides information about an individuals mate quality in terms of health and strength. This article reviews the role of body movement in human non-verbal communication, and highlights its significance in human mate preferences in order to promote future work in this research area within the evolutionary psychology framework

    Evaluation of ASTER GDEM ver2 using GPS measurements and SRTM ver4.1 in China

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    The freely available ASTER GDEM ver2 was released by NASA and METI on October 17, 2011. As one of the most complete high resolution digital topographic data sets of the world to date, the ASTER GDEM covers land surfaces between 83°N and 83°S at a spatial resolution of 1 arc-second and will be a useful product for many applications, such as relief analysis, hydrological studies and radar interferometry. The stated improvements in the second version of ASTER GDEM benefit from finer horizontal resolution, offset adjustment and water body detection in addition to new observed ASTER scenes. This study investigates the absolute vertical accuracy of the ASTER GDEM ver2 at five study sites in China using ground control points (GCPs) from high accuracy GPS benchmarks, and also using a DEM-to-DEM comparison with the Consultative Group for International Agriculture Research Consortium for Spatial Information (CGIAR-CSI) SRTM DEM (Version 4.1). And then, the results are separated into GlobCover land cover classes to derive the spatial pattern of error. It is demonstrated that the RMSE (19m) and mean (-13m) values of ASTER GDEM ver2 against GPS-GCPs in the five study areas is lower than its first version ASTER GDEM ver1 (26m and -21m) as a result of the adjustment of the elevation offsets in the new version. It should be noted that the five study areas in this study are representative in terms of terrain types and land covers in China, and even for most of mid-latitude zones. It is believed that the ASTER GDEM offers a major alternative in accessibility to high quality elevation data

    Genome Sequences for Three Strains of Kocuria rosea, Including the Type Strain

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    Genomes from three strains of Kocuria rosea were sequenced. K. rosea ATCC 186, the type strain, was 3,958,612 bp in length with a total G+C content of 72.70%. When assembled, K. rosea ATCC 516 was 3,862,128 bp with a 72.82% G+C content. K. rosea ATCC 49321 was 4,018,783 bp in size with a 72.49% G+C content

    Aerospace medicine and biology: A continuing bibliography with indexes (supplement 352)

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    This bibliography lists 147 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during July 1991. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance

    Reason, causation and compatibility with the phenomena

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    'Reason, Causation and Compatibility with the Phenomena' strives to give answers to the philosophical problem of the interplay between realism, explanation and experience. This book is a compilation of essays that recollect significant conceptions of rival terms such as determinism and freedom, reason and appearance, power and knowledge. This title discusses the progress made in epistemology and natural philosophy, especially the steps that led from the ancient theory of atomism to the modern quantum theory, and from mathematization to analytic philosophy. Moreover, it provides possible gateways from modern deadlocks of theory either through approaches to consciousness or through historical critique of intellectual authorities. This work will be of interest to those either researching or studying in colleges and universities, especially in the departments of philosophy, history of science, philosophy of science, philosophy of physics and quantum mechanics, history of ideas and culture. Greek and Latin Literature students and instructors may also find this book to be both a fascinating and valuable point of reference

    Pharmaceutical compounding of orphan active ingredients in Belgium : how community and hospital pharmacists can address the needs of patients with rare diseases

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    Background: Pharmaceutical compounding of orphan active ingredients can offer cost-effective treatment to patients when no other drug product is available for a rare disease or during periods of drug product shortages. Additionally, it allows customized therapy for patients with rare diseases. However, standardized compounding formulas and procedures, and monographs are required to ensure the patients' safety. Results: Standardized formulas and compounding procedures were developed for seven orphan active ingredients (L-arginine, sodium benzoate, sodium phenylbutyrate, L-carnitine, chenodesoxycholic acid, primaquine phosphate, pyridoxal phosphate) and one non-orphan molecule (sodium perchlorate) regularly compounded by hospital pharmacists for extemporaneous use. The stability of these formulations was evaluated over 3months at refrigerated (5 degrees C) and standard storage conditions (25 degrees C/60%RH) using HPLC-based assays and a suitable shelf life was assigned to the formulations. Additionally, suitable analytical methods for quality control of formulations of pyridoxal phosphate and sodium perchlorate were developed as monographs for these components were not available in the European Pharmacopeia or United States Pharmacopeia. Conclusions: Availability of compounding formulas and protocols, as well as stability information, for orphan active ingredients can improve patients' access to treatment for rare diseases. Such data were collected for seven orphan active ingredients to treat patients with rare diseases when no other treatment is available. More efforts are needed to develop standardized formulas and compounding procedures for additional orphan active ingredients whose clinical efficacy is well-known but which are not available as products with a marketing authorization. Additionally, a legal framework at EU level is required to enable the full potential of pharmaceutical compounding for orphan active ingredients

    Aerospace medicine and biology: A continuing bibliography with indexes (supplement 327)

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    This bibliography lists 127 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during August, 1989. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance
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