bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixing in massive stellar mergers
Authors: Gaburov E. , Lombardi J. C. , Portegies Zwart S. 
Published: November 2007

Abstract
The early evolution of dense star clusters is possibly dominated by close interactions between stars, and physical collisions between stars may occur quite frequently. Simulating a stellar collision event can be an intensive numerical task, as detailed calculations of this process require hydrodynamic simulations in three dimensions. We present a computationally inexpensive method in which we approximate the merger process, including shock heating, hydrodynamic mixing and mass loss, with a simple algorithm based on conservation laws and a basic qualitative understanding of the hydrodynamics of stellar mergers. The algorithm relies on Archimedes' principle to dictate the distribution of the fluid in the stable equilibrium situation. We calibrate and apply the method to mergers of massive stars, as these are expected to occur in young and dense star clusters. We find that without the effects of microscopic mixing, the temperature and chemical composition profiles in a collision product can become double-valued functions of enclosed mass. Such an unphysical situation is mended by simulating microscopic mixing as a post-collision effect. In this way we find that head-on collisions between stars of the same spectral type result in substantial mixing, while mergers between stars of different spectral type, such as type B and O stars (∼10 and ∼40 M⊙ respectively), are subject to relatively little hydrodynamic mixing. Our algorithm has been implemented in an easy-to-use software package, which we have made publicly available for download.1
A cautionary note on cosmological magnetic fields
Authors: Teodoro Luís F. A. , Diver Declan A. , Hendry Martin A. 
Published: November 2007

Abstract
This note is concerned with potentially misleading concepts in the treatment of cosmological magnetic fields by magnetohydrodynamical (MHD) modelling. It is not a criticism of MHD itself but rather a cautionary comment on the validity of its use in cosmology. Now that the relevant cosmological data are greatly improved compared with a few decades ago, and even better data are imminent, it makes sense to revisit original modelling assumptions and examine critically their shortcomings in respect of modern science. Specifically, this Letter argues that ideal MHD is a poor approximation around recombination, since it inherently restricts evolutionary time-scales, and is often misapplied in the existing literature.
INFLUENCE OF SODIUM TRIPOLYPHOSPHATE (STP) TREATMENT AND COOKING TIME ON COOK LOSSES AND TEXTURAL PROPERTIES OF RED MEATS
Authors: ERDOGDU S. BELGIN , ERDOGDU FERRUH , EKIZ H. IBRAHIM 
Published: November 2007

ABSTRACT Sodium tripolyphosphates (STPs) are important functional additives used in meat products. STPs reduce cook losses and improve textural properties, especially by increasing the water‐holding capacity of proteins. However, increases in cooking time or temperature enhance meat proteins' denaturation, resulting in a reduced water‐holding capacity. The amount of STPs diffused into meats would play an important role for these changes. Therefore, the objectives of this research were to determine the effects of processing conditions (cooking time, STP concentration and dipping time) on cook losses and textural properties of red meats, and to relate these changes with diffused amount of STPs. For this purpose, meats (2 × 2 × 2 cm in size) were dipped in different concentrations of STP solutions (2, 4 and 6%) for 10, 20 and 30 min, and were cooked in boiling water for 5, 10 and 15 min. Cook losses were calculated from weight changes, and textural properties were determined by applying texture profile analysis to data obtained using Texture Analyzer TA‐XT2i (Stable Micro Systems, Godalming, Surrey, U.K.). STPs were found to decrease cook losses and hardness values. While an increase in STP concentration increased cohesiveness, increase in cooking time resulted in higher hardness, gumminess, chewiness and cook losses. An increase in dipping times also decreased the cook losses and hardness. The results showed that STP concentration, STP dipping and cooking times had significant effects on the changes of textural properties and cook losses of meats. These results may be used for further meat processing optimization studies if they get correlated with sensory data obtained at the same conditions. PRACTICAL APPLICATIONSCooking to assure safety of food products leads to changes in sensory attributes. The major changes occurring in meats are shrinkage, toughening of tissues, releasing of meat juice and color due to the effect of thermal treatment on proteins. Based on these, resulting cook losses for economical considerations and changes in textural properties affecting consumer satisfaction are widely recognized. Because the meat processing industry uses sodium tripolyphosphates (STPs) to improve textural properties and to reduce cook losses, the objective of this research was to determine the effects of STPs and cooking time on cook losses and textural properties of red meats. The results showed that STPs and cooking time affected the changes in cook losses and textural properties significantly. In addition to these results, an optimization study for decreasing cook losses while improving textural properties should be conducted where these changes are attributed to be significant for human perception using a sensory panel.
COMPARISON OF MECHANICAL PROPERTIES OF SOME SELECTED ALMOND CULTIVARS WITH HARD AND SOFT SHELL UNDER COMPRESSION LOADING
Authors: AKTAS TURKAN , POLAT REFIK , ATAY UMRAN 
Published: November 2007

ABSTRACT The mechanical properties of Nonpareil versus Gulcan 101‐23 almond cultivars that have different shell properties were loaded between two parallel plates to determine the rupture force, rupture energy, rupture power requirement, toughness and firmness. The tests were carried out with three moisture contents, namely, 7.2, 22.9 and 33.6% wet basis and three loading axes (x, y, z). Physical characteristics of the almond cultivars such as length, width, thickness, geometric mean diameter, sphericity, volume, surface area and weight were determined. Physical properties of both cultivars increased as a numerical by increasing moisture content. The highest rupture force in all moisture content levels was obtained for almond pit loaded along the y‐axis. In addition to rupture force, values of absorbed energy, toughness, power requirement and firmness were calculated as mechanical properties. The maximum force required to initiate pit rupture was found as maximum 554.3 N at y‐axis for 7.2% moisture content and minimum 126.9 N at x‐axis for 33.6% moisture content for Gulcan 101‐23 cultivar. These values were determined as 53.3 and 11.2 N, respectively, for Nonpareil cultivar. Rupture force, absorbed energy, toughness, power requirement and firmness decreased with an increase of moisture content. The difference between mechanical properties of Nonpareil versus Gulcan 101‐23 almond cultivars was found to be highly significant (P < 0.001).PRACTICAL APPLICATIONSAs almond production increases in the world, almond processes are performed by hand or by using old techniques. Therefore, major quality loss during harvesting and postharvesting processes of almonds occurs. The most critical and delicate operation in postharvesting processes is pit cracking to extract the fragile whole edible kernel from the almond pit. This process is still carried out by hand or by using an apricot cracking equipment. But this is not the right process because shell hardness of almond pit changes in relation to almond cultivars. While some almond pits can be cracked using high power and some apparatus, some of them can be cracked even by hand easily. The cracking operation causes damage and broken kernels because of the excessive mechanical forces. The extent and type of damage depend on the physical characteristics, cultivar and applied force. For this reason, systems must be designed while taking these criteria into consideration to prevent inadequate applications.
From Theory to Practice: General Trends in Foreign Language Teaching Methodology and Their Influence on Language Assessment
Authors: Campbell Christine , Duncan Greg 
Published: November 2007

AbstractIn the late 1970s, language‐learning theorists redefined ability in a second or foreign language, emphasizing its communicative aspects. The proficient linguist was one who could function effectively in the four skills of speaking, writing, reading comprehension, and listening comprehension in real‐life, not contrived or artificial, contexts. This new paradigm led to change in language‐teaching methodology; communicative language teaching became the prevailing approach. From that time through the present, developments in language‐teaching methodology have both informed trends in language assessment and been influenced by them. One recent pivotal development has been the creation and implementation of the national standards for foreign language learning. The product of both theorists and practitioners, the standards broadened the concept of ability to include the capacity to perform in 11 standards that fall under five goal areas: communication, cultures, connections, comparisons, and communities. However, although the original standards describe the content of instruction, they do not specify performance standards for each of the 11 content standards or provide assessments. As a result, the profession has had to rise to the challenge of producing standards‐based assessments in K‐16. Select state and school district programs have devised model assessments; others are gradually following suit. With the standards as a catalyst, both teaching and testing will undoubtedly continue to evolve in a positive direction.
Identification of
Streptococcus uberis
Multilocus Sequence Types Highly Associated with Mastitis
Authors: Tomita Takehiro , Meehan Brian , Wongkattiya Nalin , Malmo Jakob , Pullinger Gillian , Leigh James , Deighton Margaret 
Published: November 2007

ABSTRACT

Multilocus sequence typing analysis of
Streptococcus uberis
has identified a cluster of isolates associated with clinical and subclinical mastitis and a cluster associated with cows with low somatic cell counts in their milk. Specific groups of genotypes (global clonal complex [GCC] sequence type 5s [ST5s] and GCC ST143s) were highly associated (
P
= 0.006) with clinical and subclinical mastitis and may represent a lineage of virulent isolates, whereas isolates belonging to GCC ST86 were associated with low-cell-count cows. This study has, for the first time, demonstrated the occurrence of identical sequence types (ST60 and ST184) between different continents (Australasia and Europe) and different countries (Australia and New Zealand). The standardized index of association and the empirical estimation of the rate of recombination showed substantial recombination within the
S. uberis
population in Australia, consistent with previous multilocus sequence type analyses.
‘Come and Get it’: Distributional Biases in Social Service Delivery Systems
Authors: Gibson D. M. , Goodin Robert E. , Grand Julian Le 
Published: November 2007

In examining patterns of utilization of medical and paramedical services by the Australian elderly, Gibson (1983) made an interesting, counterintuitive discovery. While it is only to be expected that a person’s income should constitute a barrier to service utilization, it was somewhat surprising to find that barrier persisting even when services were publicly-funded. Even more surprisingly, that barrier seemed to persist for publicly-funded, publicly-provided services but to disappear for services which were publicly-funded but privately-provided.
That finding runs counter to our ordinary expectations. After all, it is the private market in which income has the most direct role in rendering people’s desires into ‘effective demand’. Whatever impact income has on the delivery of goods and services from the public sector must surely be less direct, and therefore presumably less strong. Yet paradoxically, where service utilization is concerned, low income seems to be a hindrance in the public sector but not in the publicly-funded private sector.
This essay offers a general theory aimed at dissolving that paradox. While it is essentially a theoretical exercise, our analysis does turn crucially at several points on empirical speculations that will ultimately require far more testing in far more countries and far more policy contexts.
Local Planning Authority Controls over Pollution
Authors: Wood Christopher 
Published: November 2007

This paper is concerned with the control of pollution by local planning authorities. In particular, it summarises and analyses five case histories of the attempts of planning authorities to control land, air and noise pollution. The examples presented all refer to the United Kingdom but the issues raised appear to be reasonably typical of the implementation of most national pollution control processes. These issues include the conflict between corporate (or economic) and environmental interests, the conflicts between central and local government objectives and the role of the land use planning authority in environmental mediation.
Land use planning can never be the major instrument of pollution control but it does have a very important role in the juxtaposition of polluting land uses (eg industry, major roads) and sensitive land uses (eg housing, hospitals) and in the imposition of conditions on both types of development designed to reduce the effects of pollution. Further, in the United Kingdom, as in some other countries, land use planning decisions are often open to public involvement and pressure in a way that is not true of other types of pollution control. This openness gives planning decisions relating to pollution a unique significance.
Expression of Pluripotent Stem Cell Markers in the Human Fetal Testis
Authors: Kerr Candace L. , Hill Christine M. , Blumenthal Paul D. , Gearhart John D. 
Published: November 2007

AbstractHuman primordial germ cells (PGCs) have proven to be a source of pluripotent stem cells called embryonic germ cells (EGCs). However, the developmental potency of these cells in the fetal gonad still remains elusive. Thus, this study provides a comprehensive analysis of pluripotent and germ cell marker expression in human fetal testis 7–15 weeks postfertilization (pF) and compares this expression to their ability to derive EGCs. Although the majority of germ cells expressed stem cell markers stage-specific embryonic antigen (SSEA) 1, SSEA4, EMA-1, and alkaline phosphatase, only a small percentage of those (&lt;1%) expressed OCT4, CKIT, and NANOG. Specifically, the number of OCT4+/CKIT+/NANOG+ cells significantly increased in the developing cords during weeks 7–9, followed by a gradual decline into week 15 pF. By week 15 pF, the remaining OCT4+/CKIT+/NANOG+ cells were found in the cords surrounding the periphery of the testis, and the predominant germ cells, CKIT+ cells, no longer expressed OCT4 or NANOG. Based on morphology and early germ cell marker expression, including VASA, PUM2, and DAZL, we suggest these cells are mitotically active gonocytes or prespermatogonia. Importantly, the number of OCT4+ cells correlated with an increase in the number of EGC colonies derived in culture. Interestingly, two pluripotent markers, Tra-1–60 and Tra-1–81, although highly expressed in EGCs, were not expressed by PGCs in the gonad. Together, these results suggest that PGCs maintain expression of pluripotent stem cell markers during and after sexual differentiation of the gonad, albeit in very low numbers.Disclosure of potential conflicts of interest is found at the end of this article.
Phase transition in CeSe, EuSe and LaSe under high pressure
Authors: Singh Sadhna , Singh R. , Gour Atul 
Published: November 2007

AbstractThe high pressure phase transition and elastic behavior of rare earth monoselenides (CeSe, EuSe and LaSe) which crystallize in a NaCl-structure have been investigated using the three body interaction potential (TBIP) approach. These interactions arise due to the electronshell deformation of the overlapping ions in crystals. The TBP model consists of a long range Coulomb, three body interactions and the short range overlap repulsive forces operative up to the second neighboring ions. The authors of this paper estimated the values of the phase transition pressure and the associated volume collapse to be closer than other calculations. Thus, the TBIP approach also promises to predict the phase transition pressure and pressure variations of elastic constants of lanthanide compounds.
Study of the third order nonlinear optical properties of Zn1−xMgxSe and Cd1−xMgxSe crystals
Authors: Derkowska B. , Firszt F. , Sahraoui B. , Marasek A. , Kujawa M. 
Published: November 2007

AbstractThird order nonlinear optical susceptibilities χ<3> of ternary Zn1−xMgxSe and Cd1−xMgxSe crystals have been measured using standard degenerate four-wave mixing (DFWM) method at 532 nm. The nonlinear transmission technique has been applied to check if our crystals exhibit two-photon absorption. The studied Zn1−xMgxSe and Cd1−xMgxSe solid solutions were grown from the melt by the modified high-pressure Bridgman method. For both crystals the energy gap increases with increasing Mg content.In the case of Zn1−xMgxSe, it was found that the value of third order nonlinear optical susceptibility χ<3> decreases with increasing Mg content. An explanation of this behaviour results from the dependence of optical nonlinearities on the energy band gap Eg of the studied crystals. In the case of Cd1txMgxSe with low content of Mg, no response was observed for the studied wavelength since the energy gap in such crystals is smaller than the photon energy of the used laser radiation.It was also found that the value of third order nonlinear optical susceptibility χ<3> for Cd0.70Mg0.30Se is higher than for Zn0.67Mg0.33Se. This behaviour can be understood if one take into consideration that the free carrier concentration in Cd1−xMgxSe samples is about four orders of magnitude higher than that in Zn1txMgxSe ones with comparable Mg content respectively. It is commonly known that when the electric conductivity increases, the values of nonlinear optical properties increase.From the performed measurements one can conclude that the incorporation of Mg as constituent into ZnSe and CdSe crystals leads to a change of the third order nonlinear optical susceptibilities.
Testicular Lesions in Rats Treated with a Sympatholytic Hypotensive Agent (Losulazine)
Authors: Mesfin G. M. , Morris D. F. , Seaman W. J. , Marks T. A. 
Published: November 2007

Groups of 25 male Sprague-Dawley rats were treated orally with losulazine at 0 (vehicle control), 4, 8, 16, or 32 mg/kg/day for 1 year. Daily clinical signs, weekly food consumption and body weight changes, and terminal hematologic and blood chemistry values were evaluated. Terminal urinalysis in 10 randomly selected rats from all groups and levels of serum luetinizing hormone, prolactin, and testosterone from control, low-, and high-dose groups were also evaluated. Fertility was determined in eight randomly selected rats from each group at 35–49 weeks. Reversibility of breeding performance was evaluated in 10 rats treated for 30 weeks and allowed to recover for 17 weeks. Selected organs were weighed and the testes and epididymides were microscopically evaluated in all rats that survived through the 1 year treatment period. Rats treated with losulazine showed dosage-dependent ptosis, somnolence, fecal softening, and decreased food consumption with a corresponding retarded body weight gain. There were no biologically significant changes in hematologic, blood chemistry, or urinalysis values between treated and control rats. Relative spleen, heart, adrenal, and brain weights were increased in treated rats. There was a reversible dosage and time-dependent decreased fertility in rats treated with losulazine for 6–12 months. The incidence of testicular tubular atrophy/degeneration, usually confined to the subcapsular areas of the testes, and concentration of degenerate ge.minal cells in the epididymides, were increased in treated compared to vehicle control rats. Testicular lesions were not dosage related, were minimal to mild after 1 year of treatment, and were not attended by a decrease in relative testicular weights. Decreased fertility was not correlated with the apparently treatment-related testicular lesions. It could not be determined whether the minor testicular lesions seen in rats treated with losulazine were related to stressful conditions the rats were apparently under or to the effects of the drug on the hypothalamus-pituitary-gonadal axis or the sympathetic nervous system.
Markers of Exposure to Carcinogens: Methods for Human Biomonitoring
Authors: Wogan Gerald N. 
Published: November 2007

Methods have been developed for the detection of exposure to carcinogens and other DNA-damaging agents in experimental animals and humans, through the detection of carcinogens or metabolic derivatives of them in body fluids or adducts bound covalently to DNA or hemoglobin. These methods are being applied in studies of exposure to environmental carcinogens, the results of which demonstrate their adequacy for detecting ambient exposures. The successful use of urinary markers of genotoxic exposures has been reported with respect to nitrosoproline as an indicator of exposure to N-nitroso compounds. The same approach has been used to detect aflatoxin B1 (AFB1) metabolites and AFB1-N7-Gua as markers of exposure to aflatoxin B1. Detection of adducts formed between genotoxic agents and hemoglobin has been reported in studies of populations occupationally exposed to ethylene oxide, in which 3-hydroxyhistidine and 3-hydroxyva-line have been measured, and in smokers, whose hemoglobin has been found to contain levels of 4-aminobiphenyl and 3-hydroxyvaline that were correlated with the frequency of cigarette smoking. Albumin adducts of AFB1 have been identified in exposed people and their levels correlated with ingested amounts of the carcinogen. DNA adducts of genotoxic agents have also been detected in the cells and tissues of exposed individuals. Several studies to date have focused on exposure to the ubiquitous polycyclic aromatic hydrocarbon benzo(a)pyrene. Immunoassays and physicochemical methods have been used to detect adducts formed through the major intermediate in the activation pathway, the benzpyrene-7,8-diol-9,10-epoxide (BPDE). BPDE adducts have been found in the DNA of peripheral leukocytes of workers in foundries, aluminum manufacturing plants, and coke oven plants, and also in roofers and cigarette smokers with the use of synchronous scanning fluorescence as well as by enzyme-linked immunosorbent assays (ELISA) or ultrasensitive enzyme radioimmunoassays (USERIA). DNA adducts of O6-methyl guanine have also been detected by immunoassay in the blood of populations at high risk for esophageal cancer. The method of 32P postlabeling has been used for the detection of DNA adducts in placentas, peripheral leukocytes, and oral mucosal cells of tobacco smokers as well as coke oven and foundry workers, and increased total levels of adducts were in general indicative of elevated levels of exposure.