bluuebunny/crossref_metadata_2025_split huggingface dataset:
Turbulence in a Sheared, Salt-Fingering-Favorable Environment: Anisotropy and Effective Diffusivities
Authors: Kimura Satoshi , Smyth William , Kunze Eric 
Published: January 2011

Abstract
Direct numerical simulations (DNS) of a shear layer with salt-fingering-favorable stratification have been performed for different Richardson numbers Ri and density ratios Rρ. In the absence of shear (Ri = ∞), the primary instability is square planform salt fingering, alternating cells of rising and sinking fluid. In the presence of shear, salt fingering takes the form of salt sheets, planar regions of rising and sinking fluid, aligned parallel to the sheared flow. After the onset of secondary instability, the flow becomes turbulent. The continued influence of the primary instability distorts the late-stage structure and hence biases isotropic estimates of the turbulent kinetic energy dissipation rate ε. In contrast, thermal and saline gradients evolve to become more isotropic than velocity gradients at their dissipation scales. Thus, the standard observational methodology of estimating the turbulent kinetic energy dissipation rate ε from vertical profiles of microscale gradients and assuming isotropy can underestimate its true value by a factor of 2–3, whereas estimates of thermal and saline dissipation rates using this approach are relatively accurate. Likewise, estimates of Γ from vertical profiles overestimate the true Γ by roughly a factor of 2. Salt sheets are ineffective at transporting momentum. Thermal and saline effective diffusivities decrease with decreasing Ri, despite the added energy source provided by background shear. After the transition to turbulence, the thermal to saline flux ratio and the effective Schmidt number remain close to the values predicted by linear theory.
Barotropic Rossby Waves Radiating from Tropical Instability Waves in the Pacific Ocean
Authors: Farrar J. Thomas 
Published: January 2011

Abstract
Tropical instability waves are triggered by instabilities of the equatorial current systems, and their sea level signal, with peak amplitude near 5°N, is one of the most prominent features of the dynamic topography of the tropics. Cross-spectral analysis of satellite altimetry observations shows that there is sea level variability in the Pacific Ocean as far north as Hawaii (i.e., 20°N) that is coherent with the sea level variability near 5°N associated with tropical instability waves. Within the uncertainty of the analysis, this off-equatorial variability obeys the dispersion relation for nondivergent, barotropic Rossby waves over a fairly broad range of periods (26–38 days) and zonal wavelengths (9°–23° of longitude) that are associated with tropical instability waves. The dispersion relation and observed wave properties further suggest that the waves are carrying energy away from the instabilities toward the North Pacific subtropical gyre, which, together with the observed coherence of the sea level signal of the barotropic waves with that of the tropical instability waves, suggests that the barotropic Rossby waves are being radiated from the tropical instability waves. The poleward transport of kinetic energy and westward momentum by these barotropic Rossby waves may influence the circulation in the subtropics.
Decadal Shifts of the Kuroshio Extension Jet: Application of Thin-Jet Theory*
Authors: Sasaki Yoshi N. , Schneider Niklas 
Published: January 2011

Abstract
Meridional shifts of the Kuroshio Extension (KE) jet on decadal time scales are examined using a 1960–2004 hindcast simulation of an eddy-resolving ocean general circulation model for the Earth Simulator (OFES). The leading mode of the simulated KE represents the meridional shifts of the jet on decadal time scales with the largest southward shift in the early 1980s associated with the climate regime shift in 1976/77, a result confirmed with subsurface temperature observations. The meridional shifts originate east of the date line and propagate westward along the mean jet axis, a trajectory inconsistent with the traditionally used linear long Rossby waves linearized in Cartesian coordinates, although the phase speed is comparable to that in the traditional framework. The zonal scale of these westward propagation signals is about 4000 km and much larger than their meridional scale. To understand the mechanism for the westward propagation of the KE jet shifts, the authors consider the limit of a thin jet. This dynamic framework describes the temporal evolution of the location of a sharp potential vorticity front under the assumption that variations along the jet are small compared to variations normal to the jet in natural coordinates and is well suited to the strong jet and potential vorticity gradients of the KE. For scaling appropriate to the decadal adjustments in the KE, the thin-jet model successfully reproduces the westward propagations and decadal shifts of the jet latitude simulated in OFES. These results give a physical basis for the prediction of decadal variability in the KE.
Dimensionally Consistent Similarity Relation of Ocean Surface Friction Coefficient in Mixed Seas*
Authors: Hwang Paul A. , García-Nava Héctor , Ocampo-Torres Francisco J. 
Published: January 2011

Abstract
Applying wavelength scaling, dimensionally consistent expressions of the ocean surface friction coefficient can be developed for both wind sea and mixed sea in the ocean. For a wind sea with a monopeak wave spectrum, the natural choice of the scaling wavelength is that of the spectral peak component. For a mixed sea with a multipeak spectrum, the peak component in the wind sea portion of the wave spectrum is not a good reference wavelength. A much better scaling wavelength is the weighted average of swell and wind sea following the consideration of equivalent momentum in the wave field. The resulting friction coefficient Cλ/2 is referenced to the wind speed at one-half of the scaling wavelength Uλ/2 instead of C10 referenced to the neutral wind speed at 10-m elevation U10. Although referencing the wind speed at a fixed elevation such as U10 is of practical necessity, Uλ/2 is physically significant as the free-stream velocity in wave-modulated boundary layer flows. A simple procedure to apply the similarity relation of Cλ/2 to obtain C10 is described.
The Influence of Island Topography on Typhoon Track Deflection
Authors: Huang Yi-Hsuan , Wu Chun-Chieh , Wang Yuqing 
Published: January 2011

Abstract
High-resolution simulations for Typhoon Krosa (2007) and a set of idealized experiments are conducted using a full-physics model to investigate the eminent deflection of typhoon track prior to its landfall over mountainous island topography. The terrain height of Taiwan plays the most important role in Typhoon Krosa’s looping motion at its landfall, while the surface properties, details in the topographic shape of Taiwan, and the cloud microphysics are shown to be secondary to the track deflection. A simulation with 3-km resolution and realistic model settings reproduces the observed Krosa’s track, while that with 9-km resolution fails, suggesting that high resolution to better resolve the typhoon–terrain interactions is important for the prediction and simulation of typhoon track deflection prior to landfall. Results from idealized experiments with model configurations mimicking those of Supertyphoon Krosa show that vortices approaching the northern and central topography are significantly deflected to the south before making sharp turns to the north, forming a kinked track pattern prior to and during landfall. This storm movement is consistent with the observed looping cases in Taiwan.
Both real-case and idealized simulations show strong channel winds enhanced between the storm and the terrain when deflection occurs. Backward trajectory analyses support the concept of the channeling effect, which has been previously found to be crucial to the looping motion of Typhoon Haitang (2005) as well. However, the inner-core asymmetric ventilation flow does not match the movement of a deflected typhoon perfectly, partly because the steering flow is not well defined and could not completely capture the terrain-induced deflection in the simulation and in nature.
Metformin decreases thyrotropin in overweight women with polycystic ovarian syndrome and hypothyroidism
Authors: Morteza Taghavi S. , Rokni Hale , Fatemi Sedigheh 
Published: January 2011

Objective: To assess the effect of metformin administration on thyroid function in overweight women with polycystic ovarian syndrome (PCOS). Methods: Twenty-seven overweight women with PCOS and hypothyroidism were selected. Fifteen patients (group I) were treated with metformin 1500 mg/day for 6 months and 12 patients (group II) with placebo. Serum thyrotropin (TSH), free T3 and free T4 were measured at baseline and 6 months after the beginning of the study. Results: A significant decrease ( p<0.001) in TSH levels was observed in group I but not in group II subjects after 6 months of metformin treatment. No significant change in free T3 and free T4 was observed throughout the study in any group. Conclusion: In obese PCOS patients with primary hypothyroidism, metformin results in a significant fall and sometimes normalisation of TSH, without causing any reciprocal changes in other thyroid function parameters.
Isothiocyanatoluminol as a Chemiluminescence Labeling Reagent for Amino Acids and Proteins
Authors: Smanmoo Srung , Nasomphan Weerachai , Tangboriboonrat Pramuan 
Published: January 2011

Abstract
Isothiocyanatoluminol (ITL) was successfully synthesized from the reaction between luminol and thiophosgene in the presence of triethylamine. The optimized conditions were extended for the preparation of isothiocyanatoisoluminol (ITIL) and phenyl isothiocyanate (PI). The chemiluminescence (CL) of ITL was comparable to luminol. ITL was used as a CL labeling reagent for amino acid and bovine serum albumin (BSA) in which the –NH2 terminus of amino acid residue present in BSA acts as the labeling site.
Spiral Pattern Formation on Bulk Metallic Glass by Electropolishing
Authors: Kido Hideki , Fujita Kazutaka , Osaki Koichi , Sakurai Tatsunari , Inoue Akihisa 
Published: January 2011

Abstract
Spiral patterns that have concave and convex surfaces were discovered on a bulk metallic glass (BMG), Zr55Cu30Al10Ni5 atom % alloy after electropolishing under certain conditions. The observed spiral pattern had a wavelength of 2.4 µm and peaks that were 0.19 µm high. Electropolishing produces smooth metal and alloy surfaces. These patterns depend on the spatiotemporal properties during electropolishing.
Formation of a Unique Fluorosilene–KF Complex Bearing Bulky Substituents
Authors: Mieda Eiko , Sasamori Takahiro , Sase Shohei , Goto Kei , Tokitoh Norihiro 
Published: January 2011

Abstract
We report here the attempted synthesis of a stable 1-fluoro-2-hydrosilene bearing a Bpq group, which is a bulky aryl group bearing a cavity-shaped framework. We have successfully synthesized an overcrowded benzyldifluorosilane as a precursor. Treatment of the benzyldifluorosilane with 2 equiv of t-BuOK in THF afforded the corresponding benzyl anion, the structure of which showed a unique feature as a fluorosilene–KF complex.
Mechanical Reinforcement of Supramolecular Hydrogel through Incorporation of Multiple Noncovalent Interactions
Authors: Komatsu Harunobu , Ikeda Masato , Hamachi Itaru 
Published: January 2011

Abstract
Supramolecular hydrogel, comprising a three-dimensional network of self-assembled nanofibers, has recently emerged as a unique material for a variety of potential applications such as tissue engineering. One serious drawback of supramolecular hydrogels that sometimes limits their practical usage is their mechanical weakness compared with conventional polymer gels. Here we describe a stiff supramolecular hydrogel made of a zwitterionic amino acid-tethered amphiphilic molecule that self-assembles into nanofibers through multiple and orthogonal noncovalent interactions.
Sperm preservation in children: a prescription for consistency with both child protection and the criminal law
Authors: Wheeler Robert , Kohler Jan , Paget Julia , Major Jessica 
Published: January 2011

People under the age of 18 with cancer sometimes require treatments that render them infertile. It may therefore be necessary, during the brief interval between diagnosis and the commencement of cancer treatment, to offer them the opportunity to produce sperm, through masturbation, for cryopreservation. The article provides a framework for justifying this as a clinical activity, and avoiding it being construed as a sexual activity under the terms of the criminal law. Of equal importance, the article puts into place measures to ensure that this clinical activity is entirely consistent with the safeguarding principles of child protection.
Down's syndrome: screening and antenatal diagnosis regionally in England and Wales 1989–2008
Authors: De Souza E , Alberman E , Morris J K 
Published: January 2011

Objective To illustrate regional changes that occurred in screening for Down's syndrome (trisomy 21) in England and Wales from 1989 to 2008. Methods The National Down Syndrome Cytogenetic Register has collected data on all ante- and postnatal diagnoses of Down's syndrome in England and Wales since 1989 ( n = 27,954). The percentages of (i) diagnoses made antenatally, (ii) antenatal diagnoses that had nuchal translucency (NT) measured, and (iii) antenatal diagnoses in mothers aged 37 and over with advanced maternal age as the sole recorded indication for diagnosis are presented according to where the mother lived (Government Office Region), year of diagnosis (1989–1994, 1995–2000, 2001–2006, 2007–2008), and maternal age (<37 years, ≥37 years). Results The percentage of cases diagnosed antenatally has increased in younger women but varies between regions. It remained relatively constant at approximately 70% in older women. The use of NT measurement in antenatal screening has expanded rapidly but varies regionally, being most common in London and the South East where, in 2007–2008, over 75% of antenatal diagnoses in older women had NT measured. The sole indication of advanced maternal age has substantially reduced, and was less than 10% in older mothers in all regions in 2007–2008. Conclusions There are regional and maternal age variations in Down's syndrome screening and diagnosis. Some regions used NT measurements, and eliminated advanced maternal age as sole reason for antenatal diagnostic testing more quickly than others. The reasons for variations need to be identified and addressed to ensure that when new screening techniques become available, regional differences are minimized.
Disease-specific mortality may underestimate the total effect of prostate cancer screening
Authors: van Leeuwen Pim J , Kranse Ries , Hakulinen Timo , Roobol Monique J , de Koning Harry J , Bangma Chris H , Schröder Fritz H 
Published: January 2011

Objectives To study the difference between the disease-specific and excess mortality rate in the European Randomized Study of Screening for Prostate Cancer section Rotterdam. Methods A total of 42,376 men were randomized to systematic screening or usual care. The excess number of deaths was defined as the difference between the observed number of deaths in the prostate cancer (PC) patients and the expected number of deaths up to 31 December 2006. The expected number was derived from mortality of all study participants before a possible diagnosis with PC. The disease-specific mortality rate was based on the number of men who died from PC. The excess mortality rate based on the arm-specific excess number of deaths and the disease-specific mortality rate were compared between the two study arms. Results The overall mortality rate was not significantly different between the intervention and the control arms of the study: RR 1.02 (95% CI 0.98–1.07). The disease-specific mortality rate was 0.42 men per 1000 person-years in the intervention and 0.48 men per 1000 person-years in the control arm: RR 0.86 (95% CI 0.64–1.17). The excess mortality rate was 0.40 per 1000 person-years in the intervention arm and 0.61 men per 1000 person-years in the control arm, and the RR for excess mortality was 0.66 (95% CI 0.39–1.13). Conclusions In contrast to the disease-specific mortality rates an increased difference in the excess mortality rates was observed between the two arms. This observation may be due to a systematic underestimation of the disease-specific deaths, and/or an additional disease-related mortality that is measured by an excess mortality analysis but not by a disease-specific mortality.
Moisture Measurements and Condensation Potential in Wood Frame Walls in a Hot-Humid Climate
Authors: Weston Theresa A. , Minnich Liza C. 
Published: January 2011

Abstract
It has long been noted that interior vapor barriers in wood frame walls in hot-humid climates can lead to interstitial condensation within walls. The bases for this recognition are predictive simulations, anecdotal observations, and a limited number of experimental studies. This paper describes an experimental study conducted in a hot-humid climate that investigated the influence of an interior vapor retarder and compares observed performance with simulation predictions. The wall performance data reviewed here was gathered as part of a larger test program evaluating the performance of a range of typical wood frame, residential wall constructions in a hot-humid climate. The approach chosen was to use real-time field exposure using a “test hut” located in Tampa, Florida. The test hut had two long sides, which provided the ability to test 16 wall specimens each. Wall specimens were instrumented with a variety of temperature, humidity, and moisture sensors. In addition to natural weather exposure, the wall specimens could be manually wetted by a water injection system to simulate rain leakage. More specifically, this paper focuses on using the data collected before and after the installation of an interior vapor barrier (vinyl wallpaper) to show the change in moisture loading and the potential condensation within the walls resulting from the installation. The field data is compared with predictions of the wall behavior using a commonly available hygrothermal model. There is increasing reliance on the use of predictive models to assess the moisture performance of building assembly designs. These predictive models need to be validated against real data to test their variance from real systems.
Revisiting Pressure Transient Testing of Hydraulically Fractured Wells: A Single, Simple and Exact Analytical Solution Covering Bilinear, Linear, and Transition in between Flow Regimes
Authors: Lietard Olivier , Spivey John P. 
Published: January 2011

Abstract
Quite a lot has been published about pressure transient testing of hydraulically fractured wells since the pioneering work of Heber Cinco-Ley in 1976. A common approach of the problem since 1981 has been to solve the ordinary differential equations (ODEs) of rate and pressure versus time in the Laplace domain and to invert the Laplace solution back into the time domain. This method has led to exact asymptotic solutions for the so-called early time bilinear and formation linear flow regimes. Unfortunately, the inversion of the general Laplace solution was shown to be too complex. Therefore, the pressure and pressure derivative type curves of the transition period between the bilinear and linear regimes have always been numerically generated, most often by making use of Stehfest's inversion algorithm, sometimes by discretization methods in the time domain.
This paper shows that a single, simple and exact analytical solution of the ODEs can be obtained directly in the time domain, providing that the flow within the fracture is assumed to be incompressible (no fracture storage effects). This general solution has two asymptotes for early and late times that agree perfectly with the previously published solutions for bilinear and formation linear flow regimes.
The contribution of the present paper is that it provides exact pressure and pressure derivative type curves throughout the long (six log cycles) transition period between the bilinear and linear asymptotes. It therefore allows for rigorous definitions of transition times, which had been so far numerically approximated. In addition, the proposed solution handles without any difficulty the presence of skin at fracture walls (fracture face skin).
A General Correlation for Proppant Settling in VES Fluids
Authors: Malhotra Sahil , Sharma Mukul M. 
Published: January 2011

Abstract
Polymer-free viscoelastic surfactant-based (VES) fluid systems are used to minimize damage to the proppant pack and to efficiently transport proppants into fractures. Proper selection of proppants and fracturing fluids for maximum propped fracture length requires reliable data and correlations for the impact of fracture fluid viscoelasticity and the effect of fracture walls on proppant settling. Current models and correlations neglect the important influence of fluid elasticity on proppant transport. This paper presents an experimental study that investigates the impact of fluid elasticity and fracture width and presents a general correlation for proppant settling in VES fluids.
Proppant settling experiments are performed in shear thinning VES fluids. Experimental data is presented to show that fluid elasticity plays an important role in controlling the settling rate of proppants. Increasing fluid elasticity can either increase or decrease the settling velocity depending on the rheological properties of the fluid and the properties of the proppants. A new experimental correlation is presented to quantify the settling velocity of proppants in VES fluids as a function of the fluid rheology and proppant size. It is shown that the VES fluids should be designed such that the relaxation time is greater than the critical relaxation time (Tcrit).
The productivity of fractured wells depends strongly on proper placement of proppants in the fracture. Experimental data/correlations are presented for the first time to show that the settling velocity of proppants is significantly impacted by the fracture width and in VES fluids this dependence is different than for the non-elastic fluids. Data is presented to show that settling velocity is reduced as proppant size becomes comparable to the fracture width. Results show that elasticity reduces the retardation effect caused by fracture walls. An experimental correlation to quantify the retardation effect due to fracture walls is presented. Proposed correlations highlight the advantages and limitations of using VES fluids for efficient proppant transport. These correlations can be directly used in fracture simulators for proppant selection and for the design of fracturing fluids.