Friction factor and heat transfer correlation for irradiated organic coolants

"September 1965."Series statement handwritten on cover"MIT-334-23 Chemistry."Also written as an M.S. theses written by the first author and advised by the second author, Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1966Includes bibliographical references (pages 163-165)M.I.T. DSR Project no. 9819Work performed for the Savannah River Operations Office, U.S. Atomic Energy Commission under contract no. AT(38-1)-33

In-pile loop irradiation studies of organic coolant materials : progress report, October 1, 1963 - December 31, 1964,

Statement of responsibility on title page reads: Report prepared by: E. A. Mason, Project Supervisor; Contributors: W.N. Bley, J.C. Kim, T.H. Timmins, J.F. Terrien, A.H. Swan"Issued: February 1, 1965.""AEC Research and Development Report"--Cover"MIT-334-12."Includes bibliographical references (leaves 21-22)Progress report; October 1, 1963 - December 31, 1964M.I.T. Project no. DSR 9819U.S. Atomic Energy Commission, Savannah River Operations Office contract no. AT(38-1)-33

Documenting the NICU design dilemma: parent and staff perceptions of open ward versus single family room units

Objective: With neonatal intensive care units (NICUs) evolving from multipatient wards toward family-friendly, single-family room units, the study objective was to compare satisfaction levels of families and health-care staff across these differing NICU facility designs. Study Design: This prospective study documented, by means of institutional review board-approved questionnaire survey protocols, the perceptions of parents and staff from two contrasting NICU environments. Result: Findings showed that demographic subgroups of parents and staff perceived the advantages and disadvantages of the two facility designs differently. Staff perceptions varied with previous experience, acclimation time and employment position, whereas parental perceptions revealed a naiveté bias through surveys of transitional parents with experience in both NICU facilities. Conclusion: Use of transitional parent surveys showed a subject naiveté bias inherent in perceptions of inexperienced parents. Grouping all survey participants demographically provided more informative interpretations of data, and revealed staff perceptions to vary with position, previous training and hospital experience

Religious affiliation modulates weekly cycles of cropland burning in Sub-Saharan Africa

Research ArticleVegetation burning is a common land management practice in Africa, where fire is used for hunting, livestock husbandry, pest control, food gathering, cropland fertilization, and wildfire prevention. Given such strong anthropogenic control of fire, we tested the hypotheses that fire activity displays weekly cycles, and that the week day with the fewest fires depends on regionally predominant religious affiliation.We also analyzed the effect of land use (anthrome) on weekly fire cycle significance. Fire density (fire counts.km-2) observed per week day in each region was modeled using a negative binomial regression model, with fire counts as response variable, region area as offset and a structured random effect to account for spatial dependence. Anthrome (settled, cropland, natural, rangeland), religion (Christian, Muslim, mixed) week day, and their 2-way and 3-way interactions were used as independent variables. Models were also built separately for each anthrome, relating regional fire density with week day and religious affiliation. Analysis revealed a significant interaction between religion and week day, i.e. regions with different religious affiliation (Christian, Muslim) display distinct weekly cycles of burning. However, the religion vs. week day interaction only is significant for croplands, i.e. fire activity in African croplands is significantly lower on Sunday in Christian regions and on Friday in Muslim regions. Magnitude of fire activity does not differ significantly among week days in rangelands and in natural areas, where fire use is under less strict control than in croplands. These findings can contribute towards improved specification of ignition patterns in regional/global vegetation fire models, and may lead to more accurate meteorological and chemical weather forecastinginfo:eu-repo/semantics/publishedVersio

Vowel reduction in word-final position by early and late Spanish-English bilinguals

Vowel reduction is a prominent feature of American English, as well as other stress-timed languages. As a phonological process, vowel reduction neutralizes multiple vowel quality contrasts in unstressed syllables. For bilinguals whose native language is not characterized by large spectral and durational differences between tonic and atonic vowels, systematically reducing unstressed vowels to the central vowel space can be problematic. Failure to maintain this pattern of stressed-unstressed syllables in American English is one key element that contributes to a ?foreign accent? in second language speakers. Reduced vowels, or ?schwas,? have also been identified as particularly vulnerable to the co-articulatory effects of adjacent consonants. The current study examined the effects of adjacent sounds on the spectral and temporal qualities of schwa in word-final position. Three groups of English-speaking adults were tested: Miami-based monolingual English speakers, early Spanish-English bilinguals, and late Spanish-English bilinguals. Subjects performed a reading task to examine their schwa productions in fluent speech when schwas were preceded by consonants from various points of articulation. Results indicated that monolingual English and late Spanish-English bilingual groups produced targeted vowel qualities for schwa, whereas early Spanish-English bilinguals lacked homogeneity in their vowel productions. This extends prior claims that schwa is targetless for F2 position for native speakers to highly-proficient bilingual speakers. Though spectral qualities lacked homogeneity for early Spanish-English bilinguals, early bilinguals produced schwas with near native-like vowel duration. In contrast, late bilinguals produced schwas with significantly longer durations than English monolinguals or early Spanish-English bilinguals. Our results suggest that the temporal properties of a language are better integrated into second language phonologies than spectral qualities. Finally, we examined the role of nonstructural variables (e.g. linguistic history measures) in predicting native-like vowel duration. These factors included: Age of L2 learning, amount of L1 use, and self-reported bilingual dominance. Our results suggested that different sociolinguistic factors predicted native-like reduced vowel duration than predicted native-like vowel qualities across multiple phonetic environments

Widespread horizontal transfer of mitochondrial genes in flowering plants

Horizontal gene transfer - the exchange of genes across mating barriers - is recognized as a major force in bacterial evolution(1,2). However, in eukaryotes it is prevalent only in certain phagotrophic protists and limited largely to the ancient acquisition of bacterial genes(3-5). Although the human genome was initially reported(6) to contain over 100 genes acquired during vertebrate evolution from bacteria, this claim was immediately and repeatedly rebutted(7,8). Moreover, horizontal transfer is unknown within the evolution of animals, plants and fungi except in the special context of mobile genetic elements(9-12). Here we show, however, that standard mitochondrial genes, encoding ribosomal and respiratory proteins, are subject to evolutionarily frequent horizontal transfer between distantly related flowering plants. These transfers have created a variety of genomic outcomes, including gene duplication, recapture of genes lost through transfer to the nucleus, and chimaeric, half-monocot, half-dicot genes. These results imply the existence of mechanisms for the delivery of DNA between unrelated plants, indicate that horizontal transfer is also a force in plant nuclear genomes, and are discussed in the contexts of plant molecular phylogeny and genetically modified plants.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62688/1/nature01743.pd

Treatment of hallux valgus by modified McBride procedure: a 6-year follow-up

PubMed ID: 20505975Background Surgical decision-making was reevaluated by comparison with an algorithm designed to analyze treatment of hallux valgus deformities. Materials and methods A modified McBride procedure was performed on 52 feet of 35 patients with hallux valgusdeformity. From this series, 36 feet of 21 patients were evaluated preoperatively, early postoperatively, and late postoperatively by means of subjective evaluation and clinical and radiological findings. Results The hallux valgus angle preoperatively, early postoperatively, and late postoperatively was 32.7 ± 8.5°, 10.1 ± 6.9°, and 20.6 ± 9.5°, respectively. Hallux valgus recurrence of 72.2% was observed. Subjective results were better and the patients rated their satisfaction with the procedure as excellent or high in 23 cases (63.9%) and moderate, low, or unsatisfactory in 13 cases (36.1%). Conclusions This level of patient satisfaction demonstrates that the McBride procedure is an efficient approach for eliminating pain due to hallux valgus deformity. © The Author(s) 2010

Treatment of hallux valgus by modified McBride procedure: a 6-year follow-up

PubMed ID: 20505975Background Surgical decision-making was reevaluated by comparison with an algorithm designed to analyze treatment of hallux valgus deformities. Materials and methods A modified McBride procedure was performed on 52 feet of 35 patients with hallux valgusdeformity. From this series, 36 feet of 21 patients were evaluated preoperatively, early postoperatively, and late postoperatively by means of subjective evaluation and clinical and radiological findings. Results The hallux valgus angle preoperatively, early postoperatively, and late postoperatively was 32.7 ± 8.5°, 10.1 ± 6.9°, and 20.6 ± 9.5°, respectively. Hallux valgus recurrence of 72.2% was observed. Subjective results were better and the patients rated their satisfaction with the procedure as excellent or high in 23 cases (63.9%) and moderate, low, or unsatisfactory in 13 cases (36.1%). Conclusions This level of patient satisfaction demonstrates that the McBride procedure is an efficient approach for eliminating pain due to hallux valgus deformity. © The Author(s) 2010

A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids

The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America.The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at -67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea.The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian

Accreting Millisecond X-Ray Pulsars

Accreting Millisecond X-Ray Pulsars (AMXPs) are astrophysical laboratories without parallel in the study of extreme physics. In this chapter we review the past fifteen years of discoveries in the field. We summarize the observations of the fifteen known AMXPs, with a particular emphasis on the multi-wavelength observations that have been carried out since the discovery of the first AMXP in 1998. We review accretion torque theory, the pulse formation process, and how AMXP observations have changed our view on the interaction of plasma and magnetic fields in strong gravity. We also explain how the AMXPs have deepened our understanding of the thermonuclear burst process, in particular the phenomenon of burst oscillations. We conclude with a discussion of the open problems that remain to be addressed in the future.Comment: Review to appear in "Timing neutron stars: pulsations, oscillations and explosions", T. Belloni, M. Mendez, C.M. Zhang Eds., ASSL, Springer; [revision with literature updated, several typos removed, 1 new AMXP added