bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two-step gradation of particle size in an inorganic-organic hybrid
Authors: Chen Tzehan , Chow Brian J. , Qiao Yu 
Published: June 2014

AbstractAn inorganic-organic hybrid (IOH) of silica particulates and polyethylene (PE) was investigated, where silica was employed as an analogue to lunar soil. The objective was to search for the optimum materials design strategy for “lunar cements” – infrastructural materials based on locally harvestable resources on the Moon. If the silica particulate size was uniform, the flexure strength of the IOH decreased quite linearly with the PE content. With a two-step size gradation of silica particulates, the flexure strength of the silica-PE IOH could be much improved, higher than that of Portland cements with only 4 wt% of PE. A threshold PE content around 6 wt% existed. Above the threshold, the PE content has only a secondary effect on the IOH flexure strength; below the threshold, the IOH flexure strength decreases abruptly. In order to further enhance the IOH strength and to reduce the binder content, this threshold value must be minimized.
Physical Model for Studying the Migration of Fine Particles in the Railway Substructure
Authors: Duong T. V. , Cui Y. J. , Tang A. M. , Dupla J. C. , Canou J. , Calon N. , Robinet A. , Chabot B. , De Laure E. 
Published: June 2014

Abstract
To study the interlayer creation and the mud-pumping phenomena in the conventional French railway substructure, a physical model was developed with a 160-mm-thick ballast layer overlaying a 220-mm-thick artificial silt layer (mixture of crushed sand and kaolin), both layers being compacted in a transparent cylinder of a 550-mm-inner diameter. One positive pore water pressure sensor, three tensiometers, and three time domain reflectometer (TDR) sensors were installed around the ballast/silt interface allowing the evolution of pore water pressure (negative or positive) and volumetric water content to be monitored, respectively. A digital camera was installed allowing direct monitoring of different movements (ballast, ballast/subsoil interface, etc.). The effects of loading (monotonic and cyclic loadings) and degree of saturation of subsoil (w = 16 %, Sr = 55 %, and near-saturation state) were investigated. It was found that the development of pore water pressure in the subsoil is the key factor causing the migration of fine particles, hence, resulting in the creation of interlayer, as well as mud pumping. In particular, the camera exposed the pumping up level of fine particles during the test, showing that the migration of fine particles was not only a result of the interpenetration of ballast particles and subsoil, but also of the pore water pressure that pushed the fine particle upward. The quality of the recorded data showed that the physical model developed worked well and the test protocol adopted for studying the mechanisms of intermixing of ballast and subsoil and mud pumping was appropriate.
Longitudinal Heat Flow Calorimetry: A Method for Measuring the Heat Capacity of Rock Specimens Using a Divided Bar
Authors: Antriasian A. , Beardsmore G. 
Published: June 2014

Abstract
We present a method for measuring the heat capacity of a rock specimen using a divided bar apparatus in a “transient” mode. The specific heat capacity can be derived if the mass of the specimen is known. Thermal conductivity can be measured during a steady-state phase of the measurement process, and longitudinal thermal diffusivity can also be derived if the specimen volume (and hence density) is measured. A divided bar delivers a longitudinal flow of heat through a rock specimen and is conventionally used only in a steady-state mode for thermal conductivity measurements. Our method employs a time-series record of temperature changes at four points along the divided bar assembly to compare the net thermal energy absorbed by a specimen to its change in temperature during thermal re-equilibration from one steady-state temperature to another. The technique is calibrated using a set of analytical standards of known heat capacity. Our method yields mean values of specific heat capacity within ±1 % of published values for cultured quartz. Repeated measurements on the same specimens also give consistent results within approximately ±1 %. A combined thermal conductivity and heat capacity measurement takes less than one hour per specimen. Our method can be replicated with any divided bar apparatus employing a precise electronic temperature control system capable of switching between two steady-state mean temperatures, along with a digital data-logging system capable of recording and displaying data at a rate of one record per second.
Assessing the Effects of Mechanical Preventive Measures on Alkali-Silica Reaction Expansion with Accelerated Mortar Bar Test
Authors: Musaoglu Orhan , Turanli Lutfullah , Saritas Afsin 
Published: June 2014

Abstract
This paper presents a modification to the apparatus of the mortar bar test of ASTM C490 in order to assess and compare the influence of mechanical preventive measures in reducing alkali-silica reaction (ASR) expansion in concrete with respect to the traditional measures. For this purpose, reinforced mortar specimens with or without pre-stressing force applied were examined and the effects of the reinforcement ratio and pre-stressing force on ASR-induced expansion and cracking were studied through the accelerated mortar bar test method of ASTM C1260. The mechanical preventive measure was also compared with a traditional preventive measure by using fly ash. The results show that reinforcement and pre-stressing force play a role in limiting expansion and cracking due to ASR and that the developed test apparatus in this study can be used for measurements.
Comparative Study of Basic Test and Resistance Curve Methods for Fracture Toughness Evaluation of Heat-Treated Zr-2.5Nb Alloy
Authors: Khandelwal H. K. , Singh R. N. , Bind A. K. , Sunil Saurav , Chakravartty J. K. 
Published: June 2014

Abstract
ASTM E1820-11, the most widely adopted standard for the determination of fracture toughness parameters, recommends two ductile crack growth correction methods for the evaluation of the J-integral parameter, viz., the basic test (BT) method and the resistance curve test (RC) method. In the present work, a comparison between the fracture toughness parameters obtained using these two methods for heat-treated Zr-2.5Nb alloy at 25°C and 300°C is presented. In order to examine the influence of a material's microstructural condition on the fracture toughness results obtained via these two methods, Zr-2.5Nb alloy was investigated under six solution heat-treated conditions after getting soaked at 850°C, 870°C, or 890°C for either 15 min or 30 min followed by water quenching. The BT method predicted a higher J parameter than the RC method for a given crack length. This deviation in the magnitude of J increased with increasing crack length and was found to be almost twice as much at room temperature as the deviation observed at 300°C. For smaller crack lengths (i.e., up to a/W &lt; 0.54), the J parameters determined using the two methods showed insignificant deviation (&lt;5 %). However, such deviation reached ∼20 %, corresponding to ∼0.63 a/W. Values of fracture toughness parameters such as JQ, Jmax, and dJ/da evaluated using the BT method were found to be higher than those obtained using the RC method. However, deviations in the JQ and Jmax parameters determined by the two methods were insignificant (less than ∼6 %), whereas the deviation in the dJ/da parameter was ∼15 %. The RC method, in contrast to the BT method, provides a marginally conservative estimation of the fracture toughness. The parameter α used in the BT method was observed to control the extent of deviation in the J–R curves derived using these methods.
Corolla Is a Novel Protein That Contributes to the Architecture of the Synaptonemal Complex of Drosophila
Authors: Collins Kimberly A , Unruh Jay R , Slaughter Brian D , Yu Zulin , Lake Cathleen M , Nielsen Rachel J , Box Kimberly S , Miller Danny E , Blumenstiel Justin P , Perera Anoja G , Malanowski Kathryn E , Hawley R Scott 
Published: June 2014

Abstract
In most organisms the synaptonemal complex (SC) connects paired homologs along their entire length during much of meiotic prophase. To better understand the structure of the SC, we aim to identify its components and to determine how each of these components contributes to SC function. Here, we report the identification of a novel SC component in Drosophila melanogaster female oocytes, which we have named Corolla. Using structured illumination microscopy, we demonstrate that Corolla is a component of the central region of the SC. Consistent with its localization, we show by yeast two-hybrid analysis that Corolla strongly interacts with Cona, a central element protein, demonstrating the first direct interaction between two inner-synaptonemal complex proteins in Drosophila. These observations help provide a more complete model of SC structure and function in Drosophila females.
Association of Maternal Hypertension and Chorioamnionitis With Preterm Outcomes
Authors: Gagliardi Luigi , Rusconi Franca , Bellù Roberto , Zanini Rinaldo ,   the Italian Neonatal Network
Published: June 2014

OBJECTIVES:
We compared the relative effect of hypertensive disorders of pregnancy and chorioamnionitis on adverse neonatal outcomes in very preterm neonates, and studied whether gestational age (GA) modulates these effects.

METHODS:
A cohort of neonates 23 to 30 weeks' GA, born in 2008 to 2011 in 82 hospitals adhering to the Italian Neonatal Network, was analyzed. Infants born from mothers who had hypertensive disorders (N = 2096) were compared with those born after chorioamnionitis (N = 1510). Statistical analysis employed logistic models, adjusting for GA, hospital, and potential confounders.

RESULTS:
Overall mortality was higher after hypertension than after chorioamnionitis (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.08–1.80), but this relationship changed across GA weeks; the OR for hypertension was highest at low GA, whereas from 28 weeks' GA onward, mortality was higher for chorioamnionitis. For other outcomes, the relative risks were constant across GA; infants born after hypertension had an increased risk for bronchopulmonary dysplasia (OR, 2.20; 95% CI, 1.68–2.88) and severe retinopathy of prematurity (OR, 1.48; 95% CI, 1.02–2.15), whereas there was a lower risk for early-onset sepsis (OR, 0.25; 95% CI, 0.19–0.34), severe intraventricular hemorrhage (OR, 0.65; 95% CI, 0.48–0.88), periventricular leukomalacia (OR, 0.70; 95% CI, 0.48–1.01), and surgical necrotizing enterocolitis or gastrointestinal perforation (OR, 0.47; 95% CI, 0.31–0.72).

CONCLUSIONS:
Mortality and other adverse outcomes in very preterm infants depend on antecedents of preterm birth. Hypertension and chorioamnionitis are associated with different patterns of outcomes; for mortality, the effect changes across GA weeks.
Impact of Vaccination on the Epidemiology of Varicella: 1995–2009
Authors: Baxter Roger , Tran Trung N. , Ray Paula , Lewis Edwin , Fireman Bruce , Black Steve , Shinefield Henry R. , Coplan Paul M. , Saddier Patricia 
Published: June 2014

BACKGROUND:When varicella vaccine was licensed in the United States in 1995, there were concerns that childhood vaccination might increase the number of adolescents susceptible to varicella and shift disease toward older age groups where it can be more severe.METHODS:We conducted a series of 5 cross-sectional studies in 1994 to 1995 (prevaccine), 2000, 2003, 2006, and 2009 in Kaiser Permanente of Northern California to assess changes in varicella epidemiology in children and adolescents, as well as changes in varicella hospitalization in people of all ages. For each study, information on varicella history and varicella occurrence during the past year was obtained by telephone survey from a sample of ∼8000 members 5 to 19 years old; varicella hospitalization rates were calculated for the entire membership.RESULTS:Between 1995 and 2009, the overall incidence of varicella in 5- to 19-year-olds decreased from 25.8 to 1.3 per 1000 person-years, a ∼90% to 95% decline in the various age categories (5–9, 10–14, and 15–19 years of age). The proportion of varicella-susceptible children and adolescents also decreased in all age groups, including in 15- to 19-year-olds (from 15.6% in 1995 to 7.6% in 2009). From 1994 to 2009, age-adjusted varicella hospitalization rates in the general member population decreased from 2.13 to 0.25 per 100 000, a ∼90% decline.CONCLUSIONS:In the 15 years after the introduction of varicella vaccine, a major reduction in varicella incidence and hospitalization was observed with no evidence of a shift in the burden of varicella to older age groups.
Мікрофлора урогенітального тракту жінок із неспецифічними вульвовагінітами та вагінозами у Дніпропетровській області
Authors: Ponedilok A. O. , Gavryliuk V. G. , Khlopova Y. V. , Vinnikov A. I. 
Published: June 2014

The spectrum of causative agents of nonspecific infections of the women urogenital tracts is studied. It is established that the typical etiological agents of the vaginosis are yeast-like fungi Candida albicans (35.7 %) and Escherichia coli (30.2 %), and the clinical isolates of E. coli (47.3 %) and Proteus mirabilis (15.8 %) are usual for vulvovaginitis. The frequency of detection of the causative agents of inflammatory genito-urinary diseases in women of different age groups varies: strains of E. coli are often found in patients of 1–12 years (47.3 %) and in women of 43–66 years old (36.0 %), but C. albicans – in patients of 18–42 years (39.0 %). High levels of the resistance to penicilline, tetracycline and fluoroquinolone antibiotics in selected clinical isolates of opportunistic microorganisms are determined.
Combinatrial study for Mg-Si thin films fabricated by RF co-sputtering with Mg and Si targets
Authors: Morita Y. , Hayashi Y. , Tsuchiura H. , Nishitani M. 
Published: June 2014

ABSTRACTMg-Si thin films were systematically studied using combinatorial approach by co-sputtering with Mg and Si targets. Single phase of Mg2Si appeared around the stoichiometric composition region, and in Mg-rich region (Mg/Si>4) Mg2Si and Mg phases coexisted. The transition of electrical conduction type from n-type to p-type occurred near the stoichiometric composition region where the strongest peak of Mg2Si appeared in the XRD patterns and the Raman scattering spectra. The p-type conduction was observed in Mg-poor region near the stoichiometric composition region. The results of first principle calculation suggest that Mg vacancy may cause p-type conduction.
Electronic properties of the ZnO:Al/n-Si (100), (110) and (111) interfaces
Authors: Lindberg Per , Quemener Vincent , Bergum Kristin , Gan Jiantuo , Svensson Bengt G. , Monakhov Edouard V. 
Published: June 2014

ABSTRACTAluminum doped ZnO (AZO) has been deposited on (100), (110) and (111) oriented n-type Si and on fused silica by atomic layer deposition (ALD). The films have been post deposition annealed in the temperature range 200-500 οC. The AZO films have been characterized by X-ray diffraction (XRD), Hall and transmittance measurements. Circular diodes have been fabricated from the AZO/Si structures and characterized by current-voltage (IV) and deep level transient spectroscopy (DLTS). The AZO films form Schottky junctions with the Si substrates for all the crystallographic orientations. It is established that after post deposition annealing the structure AZO/n-Si (110) is distinguished as the system with largest rectification.
Nuclear Magnetic Resonance as a Probe of the Topological Insulator Bi2Se3
Authors: Nisson David M. , Dioguardi Adam P. , Klavins Peter , Lin Ching H. , Shirer Kent , Shockley Abigail C. , Crocker John , Curro Nicholas J. 
Published: June 2014

ABSTRACTTopological insulators are a new class of materials with the ability to carry spin-polarized currents on their surfaces. Nuclear magnetic resonance (NMR) measurements can probe the magnetic interactions between specific isotopes and the electronic system of a material. We present 209Bi NMR spectra and relaxation rate data on single crystals of the topological insulator material Bi2Se3 grown under various conditions. Our NMR data on single crystals reveal a significant strength of coupling between the nuclear spins and the bulk carrier spins, suggesting that nuclear spins may have a sizeable effect on spin-polarized surface currents.
Electron Emission From Diamond Films
Authors: Zhirnov V.V. , Hren J.J. 
Published: June 2014

Diamond always has been considered an exciting material. In addition to its other outstanding properties, diamond's capacity for cold electron emission has become a “hot” topic of research in recent years. The electron emission from diamond films is important for both fundamental and applied purposes, which may be expressed by two questions as follows: “Why does diamond emit electrons?” and “How can an efficient cold cathode be made?”The “diamond-emission era” started in 1991. That year three papers were published, reporting unexpectedly high electron emissivity from diamond. The first paper by Djubua and Chubun was very practical, having been written by device engineers. They tried different materials for the fabrication of pointed field emission cathodes and found that emitters made from diamondlike carbon (DLC) demonstrated a lower emission threshold compared to other materials. A second paper by Wang et al. reported a low emission threshold for chemical-vapor-deposition (CVD) diamond films, whereas a third paper by Geis et al. described the fabrication and operation of diamond cold cathodes.Since 1991 hundreds of papers about electron emission from diamond and diamondlike materials have been published. The motivations for this increasing activity are prospective applications in vacuum microelectronics—that is, vacuum emission devices fabricated by modern microelectronic technologies. Experts expect that combining the physical advantages of emission devices and the technological progress in solid-state microelectronics will result in the development of an entirely new generation of high-performance electronic devices—among them, flat-panel displays and miniature microwave tubes.
Improved Production Methods in the California Fields
Authors: O'Neill Frank E. 
Published: June 2014

A large amount of work has been done by the California operators during thepast few years in an attempt to increase the recovery of oil from the wells.New methods have been devised and old methods improved with gratifying results.Much valuable equipment has been perfected and at this time every effort isbeing put forth by California operators to develop more efficient methods ofrecovery.
The greater amount of experimental work has been done in connection withpumping wells and the most marked improvement has been along this line. Therehas been no outstanding method developed in the last few years by which theproduction of flowing wells may be materially altered other than the old systemof properly adjusting the bean or flow nipple to meet the conditions in theparticular well. Some equipment has been developed in the way of adjustablebeans, beans which may be more quickly and easily changed and others which havebeen built stronger or harder at the discharge end where the greatest abrasionoccurs. All of this reverts however to the old method of controlling theflowing well by adjusting the bean to meet the rock pressure and sandconditions. At times when a flowing well shows a tendency to decrease rapidlyit has been possible to revive the well by flowing it through a larger openingfor a few minutes. This serves as a means of cleaning the well of accumulatedsediment, allowing the oil freer access to the hole. Some of the improvedmethods which have been developed are considered here. They may be groupedunder two heads:Precautions taken in drilling the wells.Methods to maintain production.

Precautions Taken in Drilling the Wells
Within the past few years it has become universal policy to core the wellsfrom a point above where the water string is to be cemented to the top of theoil sand. If not cored continuously the formation changes are usually cored.This method is applied not only to the new wells but frequently to redrillingwells where the repair work is being done with the rotary. The distance abovethe oil sand at which coring is commenced is governed by the knowledge at handof the property.
Formation Testers
Authors: O'Neill Frank E. 
Published: June 2014

The formation tester, as the name implies, is a tool built for testing thecontents of sands encountered in drilling wells without actually cementingcasing on the sand.
The tester was developed in the Mid-Continent and has been in use commerciallythere since about 1926. However, some two dozen patents have been issued onformation testers dating back to the seventies. The method apparently was anoutgrowth of the old Mother Hubbard grain or bean packer, used around casingbefore the days of cementing casing. These packers were also seated in atapered hole and if the formation tested was not satisfactory the casing waspulled loose and the hole taken down to another formation. A great deal ofexperimental work has been done in its development, and as a result of thiswork the formation tester became an accepted integral part of the petroleumdevelopment in California.
The formation tester was introduced into California some three years ago by M.O. Johnston. Months of discouraging and expensive work followed itsintroduction into this state, but one organization after another tried the tooland its use is now fairly general. Shortly after Johnston began testing inCalifornia, the Halliburton tester was also introduced into the state and nowanother too) is being introduced, the Shaffer-Boles tester.

Princaple and Operation of Testers
The principle employed in all formation testers is that of packing off thefluid in the hole above the formation to be tested and thereby preventing itfrom having access to the testing tool. This permits the fluid contained in thegiven formation to have unrestricted access to the tool. It is accomplished byrunning the tool and packer on the bottom of the drill pipe; the valves in thetool being closed while going into the hole to prevent fluid from entering thedrill pipe. The packer is then seated at the desired point, trapping thedrilling fluid above it. When this has been done, the valves in the tool areopened and the fluid from the formation is allowed to enter the empty pipethrough the tool.