bluuebunny/crossref_metadata_2025 huggingface dataset:
Customised birthweight models: Do they increase identification of at‐risk infants?
Authors: Gibbons Kristen , Chang Allan , Flenady Vicki , Mahomed Kassam , Gardener Glenn , Gray Peter H , Beckmann Michael , Rossouw Dominique
Published: April 2013

Aim

The study aims to describe the cohort of women and babies who are classified as small‐for‐gestational age (SGA) at term by both an Australian customised birthweight model (CBM) and a commonly used population‐based standard, and to investigate and compare the utility of these models in identifying babies at risk of experiencing adverse outcomes

Methods

Routinely collected data on 54 890 singleton‐term births at the Mater Mothers' Hospitals, Brisbane, with birthweight less than 4000 g between January 1997 and December 2008, was extracted. Each birth was classified as SGA (<10th centile) or not SGA by either and/or both methods: population‐based standards (SGApop) and CBM (SGAcust). Babies classified as SGApop, SGAcust or SGAboth were compared with those not classified as SGA by both methods using relative risk and 95% confidence interval, and those only classified as SGAcust were compared with those only classified as SGApop. Maternal demographics, maternal risk factors for fetal growth restriction, pregnancy and labour complications and adverse neonatal outcomes are reported.

Results

 A total of 4768 (8.7%) births were classified as SGApop, while 6479 (11.8%) were SGAcust of whom 4138 (63.9%) were also classified as SGApop. Maternal risk factors such as smoking and hypertension were statistically higher for the SGAcust group when compared with SGApop. For the majority of adverse neonatal outcomes, a trend was noted to increased identification using the CBM.

Conclusion

The CBM provides a modest improvement when compared to a population‐based standard to identity term infants at birth who are at risk of adverse neonatal outcomes.
The meanings older adolescents attach to spirituality
Authors: Spurr Shelley , Berry Lois , Walker Keith
Published: April 2013

Purpose

The purpose of this study was to explore the details of the experiences and meanings that adolescents associate with spirituality.

Design and Methods

This exploratory qualitative study used focus group discussions to uncover the experiences of 22 adolescents ages 16–19 years from two midwesternCanadian high schools.

Results

Three themes emerged: understandings of spirituality, the influence of spirituality on wellness, and the moderating influences of spirituality.

Practice Implications

The unique stories and experiences of this study's participants provide nurses with some possible starting points and ideas for dialogue related to spirituality with their adolescent clients.
Exploring influencing factors of postoperative pain in school‐age children undergoing elective surgery
Authors: Chieng Ying Jia Shermin , Chan Wai Chi Sally , Liam Joanne Li Wee , Klainin‐Yobas Piyanee , Wang Wenru , He Hong‐Gu
Published: April 2013

Purpose

The purpose of this study was to examine the influencing factors of postoperative pain among children undergoing elective surgery.

Design and Methods

A survey was conducted in 2011 with a convenience sample of 66 children, 6 to 14 years old, in a tertiary hospital in Singapore.

Results

Children experienced moderate preoperative anxiety and postoperative pain. Gender, preoperative anxiety, and negative emotional behaviors were significant influencing factors for postoperative pain. Boys reported less postoperative pain than girls.

Practice Implications

Effective strategies for assessing and managing children's preoperative anxiety are needed to achieve an optimal postoperative pain management outcome.
Variation of traits and habitat use in three species of sea kraits in Taiwan
Authors: Wang S. , Lillywhite H. B. , Cheng Y. C. , Tu M. C.
Published: April 2013

Three sympatric species of sea kraits (Laticauda spp.) were found to have different degrees of aquatic tendencies at Orchid Island (=Lanyu), Taiwan. All species move to coastal areas at night. Generally, Laticauda semifasciata remain submerged in sea water, L. laticaudata emerge onto land, but remain not far from the water's edge, while L. colubrina tend to move farther inland away from the water. Attributes of morphology and physiology can influence the performance and survival of snakes differently in aquatic or terrestrial habitats, so we hypothesize that some attributes of structure and function will vary among these three sympatric species of sea kraits. We measured parameters of the body shape, vascular lung, saccular lung and hematocrit of sea kraits to investigate possible morphological correlates of their physiology. The most aquatic species, L. semifasciata, had a significantly more laterally flattened body form, larger saccular lung volume and higher hematocrit than the other two species, whereas only few differences were found between the two less aquatic species. L. laticaudata had a significantly higher hematocrit than L. colubrina.
The Review Paradox: On The Diachronic Costs of Not Closing Rational Belief Under Conjunction
Authors: Leitgeb Hannes
Published: April 2013

We argue that giving up on the closure of rational belief under conjunction comes with a substantial price. Either rational belief is closed under conjunction, or else the epistemology of belief has a serious diachronic deficit over and above the synchronic failures of conjunctive closure. The argument for this, which can be viewed as a sequel to the preface paradox, is called the ‘review paradox'; it is presented in four distinct, but closely related versions.
Anesthesia and spinal muscle atrophy
Authors: Islander Gunilla
Published: April 2013

Spinal muscle atrophy (SMA) is autosomal recessive and one of the most common inherited lethal diseases in childhood. The spectrum of symptoms of SMA is continuous and varies from neonatal death to progressive symmetrical muscle weakness first appearing in adulthood. The disease is produced by degeneration of spinal motor neurons and can be described in three or more categories: SMA I with onset of symptoms before 6 months of age; SMAII with onset between 6 and 18 months and SMA III, which presents later in childhood. Genetics: The disease is in more than 95% of cases caused by a homozygous deletion in survival motor neuron gene 1 (SMN1). Pathophysiology: The loss of full‐length functioning SMN protein leads to a degeneration of anterior spinal motor neurons which causes muscle weakness. Anesthetic risks: Airway: Tracheal intubation can be difficult. Respiration: Infants with SMA I almost always need postoperative respiratory support. Patients with SMA II sometimes need support, while SMA III patients seldom need support. Circulation: Circulatory problems during anesthesia are rare. Anesthetic drugs: Neuromuscular blockers: Patients with SMA may display increased sensitivity to and prolonged effect of nondepolarizing neuromuscular blockers. Intubation without muscle relaxation should be considered. Succinylcholine should be avoided. Opioids: These should be titrated carefully. Anesthetic techniques: All types of anesthetic technique have been used. Although none is absolutely contraindicated, none is perfect: anesthesia must be individualized. Conclusion: The perioperative risks can be considerable and are mainly related to the respiratory system, from respiratory failure to difficult/impossible intubation.
Physiological mechanisms in plant growth models: do we need a supra‐cellular systems biology approach?
Authors: POORTER HENDRIK , ANTEN NIELS P. R. , MARCELIS LEO F. M.
Published: April 2013

In the first part of this paper, we review the extent to which various types of plant growth models incorporate ecophysiological mechanisms. Many growth models have a central role for the process of photosynthesis; and often implicitly assume C‐gain to be the rate‐limiting step for biomass accumulation. We subsequently explore the extent to which this assumption actually holds and under what condition constraints on growth due to a limited sink strength are likely to occur. By using generalized dose–response curves for growth with respect to light and CO2, models can be tested against a benchmark for their overall performance. In the final part, a call for a systems approach at the supra‐cellular level is made. This will enable a better understanding of feedbacks and trade‐offs acting on plant growth and its component processes. Mechanistic growth models form an indispensable element of such an approach and will, in the end, provide the link with the (sub‐)cellular approaches that are yet developing. Improved insight will be gained if model output for the various physiological processes and morphological variables (‘virtual profiling’) is compared with measured correlation networks among these processes and variables. Two examples of these correlation networks are presented.
Quality choices in the production of Renaissance art: Botticelli and demand
Authors: O'Malley Michelle
Published: April 2013

This article considers the impact that high demand had on the production and thus the quality of works of art. Considering Botticelli as a case study, and employing economic theory on reputation and demand, it argues that master painters made choices about the levels of excellence they produced. Drawing on the documentary and technical evidence concerning four of Botticelli's important altarpieces, the article demonstrates, through attention to the painter's approaches to design, preparation and painting technique, how Botticelli managed and controlled quality on a case‐by‐case basis in the workshop. It also argues that Botticelli maintained two individual strands of production, and that these amounted to methods of conceptualizing works of art. Referring to anthropological theory and drawing on the influential work of Hans Körner on Botticelli's workshop and the way works in series were produced, the research underlines the relationship between derivative works of art and issues of excellence and demand.
Who Gains from Boycotts? A Welfare Analysis of Consumer Activism
Authors: Han Baran
Published: April 2013

This paper explores the welfare consequences of product boycotts by linking product and labor markets. Consumers' threat of boycott can affect the firm's decision such as production location, size of operation and wage rate. Such conscientious action, however, can actually result in a welfare loss of the workers of concern as well as consumers themselves. The analysis suggests that consumers set their goals by studying the labor market and coordinating with local groups rather than demanding what may seem righteous.
Firm Entry under Financial Frictions
Authors: Casares Miguel , Poutineau Jean‐Christophe
Published: April 2013

How does a general‐equilibrium model behave when incorporating competitive firm entry that requires external finance? After conducting a steady‐state analysis, we reach three main results. First, the financial constraint has contractionary effects on both equity investment and the labor supply as they are inversely related to the marginal finance cost. Second, the dynamics of firm creation and destruction amplify the impact of changes in either productivity or banking efficiency due to procyclical firm entry. Third, a higher elasticity of substitution (that implies a lower mark‐up) cuts the number of firms and makes aggregate output fall.
Treatment Comparisons for Decision Making: Facing the Problems of Sparse and Few Data
Authors: Soares Marta O. , Dumville Jo C. , Ades A. E. , Welton Nicky J.
Published: April 2013

Advanced evidence synthesis techniques such as indirect or mixed treatment comparisons provide powerful analytic tools to inform decision making. In some cases, however, existing research is limited in quantity and/or existing research data are ‘sparse’. We demonstrate how modelling assumptions in evidence synthesis can be explored in the face of limited and sparse data by using an example where estimates of relative treatment effects were required in a synthesis of the available evidence regarding treatments for grade 3 or 4 pressure ulcers.
Simulating Spatial Dynamics and Processes in a Retail Gasoline Market: An Agent‐Based Modeling Approach
Authors: Heppenstall Alison J. , Harland Kirk , Ross Andrew N. , Olner Dan
Published: April 2013

Simulating the dynamics and processes within a spatially influenced retail market, such as the retail gasoline market, is a highly challenging research area. Current approaches are limited through their inability to model the impact of supplier or consumer behavior over both time and space. Agent‐based models (ABMs) provide an alternative approach that overcomes these problems. We demonstrate how knowledge of retail pricing is extended by using a ‘hybrid’ model approach: an agent model for retailers and a spatial interaction model for consumers. This allows the issue of spatial competition between individual retailers to be examined in a way only accessible to agent‐based models, allowing each model retailer autonomous control over optimizing their price. The hybrid model is shown to be successful at recreating spatial pricing dynamics at a national scale, simulating the effects of a rise in crude oil prices as well as accurately predicting which retailers were most susceptible to closure over a 10‐year period.
Structural, magnetic, and nanoscale switching properties of BiFeO3 thin films grown by pulsed electron deposition
Authors: Liu Hongxue , Comes Ryan , Pei Yonghang , Lu Jiwei , Wolf Stuart A.
Published: April 2013

The authors report the epitaxial growth of BiFeO3 by pulsed electron deposition and the resulting crystal quality, magnetic and nanoscale switching properties. X-ray diffraction shows high quality single phase, epitaxial (001) oriented films grown on SrTiO3 (001) substrates. Both field and temperature dependent magnetic properties reveal an antiferromagnetic behavior of the films. For the film with a SrRuO3 bottom electrode, an exchange-enhancement effect between antiferromagnetic BiFeO3 and ferromagnetic SrRuO3 was observed at low temperature. The piezoelectric force microscopy and switching spectroscopy measurements demonstrate the local domain switching process and suggest that the BiFeO3 films are high quality ferroelectrics.
MTF behavior of compressed sensing MR spectroscopic imaging
Authors: Heikal A. A. , Wachowicz K. , Fallone B. G.
Published: April 2013

Purpose:

To investigate the modulation transfer function (MTF) behavior of compressed sensing (CS) MR spectroscopic imaging (MRSI) with regard to CS reconstruction weights and the acquired peak signal‐to‐noise ratio (SNR); which may have an effect on MTF due to the nonlinear nature of the CS reconstruction process.

Methods:

A specially designed phantom consisting of wedges arranged in a fan pattern was used to calculate the MTF of the MRSI scans. Arc profiles of the phantom yield a square wave with a spatial frequency inversely proportional to the radius of the profile. The MTF was derived by considering the amplitude ratio of the fundamental frequency between the ideal square wave and the reconstructed output. As compressed sensing relies on nonlinear reconstruction and a minimization algorithm that requires the definition of reconstruction weights, the behavior of the MTF with respect to the choice of reconstruction weights and peak SNR is not intuitive. As such, simulations were used to investigate the response of the MTF to CS reconstruction weights at varying peak SNRs. The resulting optimized reconstruction weight was used to reconstruct an experimental CS‐MRSI scan of the phantom and compare the corresponding MTF to those of a fully sampled dataset, and a time‐equivalent Nyquist‐sampled low‐resolution dataset.

Results:

Simulations showed that MTFs of CS‐MRSI datasets varied widely with different reconstruction weights. Moreover, the response of the MTF to peak SNR was not consistent across the range of reconstruction weights. An optimized reconstruction weight was derived from the simulations and used in reconstructing the experimental dataset. The MTF of the experimental CS‐MRSI dataset showed improvement over the equivalent Nyquist sampled dataset at the resolution limit of 0.1 MTF, while it suffered from reduced response at low resolutions between 0.4 and 0.8 lp/cm.

Conclusions:

The authors have shown that in certain cases small variations in the reconstruction weights yield a measureable effect on the CS reconstructed images, particularly with regard to MTF. Furthermore, it was found that peak SNR affects CS‐MRSI MTF especially at higher wavelet reconstruction weights. Accordingly, prior knowledge of the expected peak SNR is essential to optimize the CS reconstruction process. Their phantom‐MTF technique provides a quantitative performance measure of MRSI sequences, through which they were able to quantify a loss of 32.4% in spatial resolution for CS‐MRSI at 0.1 MTF compared to a loss of 48.6% for the time‐equivalent Nyquist‐sampled low‐resolution scans. They also showed that CS‐MRSI suffered decreased low‐resolution response as opposed to the equivalent low‐resolution datasets.
Dosimetric comparison of patient setup strategies in stereotactic body radiation therapy for lung cancer
Authors: Wu Jianzhou , Betzing Christopher , He Tongming T. , Fuss Martin , D'Souza Warren D.
Published: April 2013

Purpose:

In this work, the authors retrospectively compared the accumulated dose over the treatment course for stereotactic body radiation therapy (SBRT) of lung cancer for three patient setup strategies.

Methods:

Ten patients who underwent lung SBRT were selected for this study. At each fraction, patients were immobilized using a vacuum cushion and were CT scanned. Treatment plans were performed on the simulation CT. The planning target volume (PTV) was created by adding a 5‐mm uniform margin to the internal target volume derived from the 4DCT. All plans were normalized such that 99% of the PTV received 60 Gy. The plan parameters were copied onto the daily CT images for dose recalculation under three setup scenarios: skin marker, bony structure, and soft tissue based alignments. The accumulated dose was calculated by summing the dose at each fraction along the trajectory of a voxel over the treatment course through deformable image registration of each CT with the planning CT. The accumulated doses were analyzed for the comparison of setup accuracy.

Results:

The tumor volume receiving 60 Gy was 91.7 ± 17.9%, 74.1 ± 39.1%, and 99.6 ± 1.3% for setup using skin marks, bony structures, and soft tissue, respectively. The isodose line covering 100% of the GTV was 55.5 ± 7.1, 42.1 ± 16.0, and 64.3 ± 7.1 Gy, respectively. The corresponding average biologically effective dose of the tumor was 237.3 ± 29.4, 207.4 ± 61.2, and 258.3 ± 17.7 Gy, respectively. The differences in lung biologically effective dose, mean dose, and V20 between the setup scenarios were insignificant.

Conclusions:

The authors’ results suggest that skin marks and bony structure are insufficient for aligning patients in lung SBRT. Soft tissue based alignment is needed to match the prescribed dose delivered to the tumors.
Potential of in vivo MRI‐based nonlinear finite‐element analysis for the assessment of trabecular bone post‐yield properties
Authors: Zhang Ning , Magland Jeremy F. , Rajapakse Chamith S. , Bhagat Yusuf A. , Wehrli Felix W.
Published: April 2013

Purpose:

Bone strength is the key factor impacting fracture risk. Assessment of bone strength from high‐resolution (HR) images have largely relied on linear micro‐finite element analysis (μ FEA) even though failure always occurs beyond the yield point, which is outside the linear regime. Nonlinear μ FEA may therefore be more informative in predicting failure behavior. However, existing nonlinear models applied to trabecular bone (TB) have largely been confined to micro‐computed tomography (μCT) and, more recently, HR peripheral quantitative computed tomography (HR‐pQCT) images, and typically have ignored evaluation of the post‐yield behavior. The primary purpose of this work was threefold: (1) to provide an improved algorithm and program to assess TB yield as well as post‐yield properties; (2) to explore the potential benefits of nonlinear μ FEA beyond its linear counterpart; and (3) to assess the feasibility and practicality of performing nonlinear analysis on desktop computers on the basis of micro‐magnetic resonance (μ MR) images obtained in vivo in patients.

Methods:

A method for nonlinearμ FE modeling of TB yield as well as post‐yield behavior has been designed where material nonlinearity is captured by adjusting the tissue modulus iteratively according to the tissue‐level effective strain obtained from linear analysis using a computationally optimized algorithm. The software allows for images at in vivo μMRI resolution as input with retention of grayscale information. Associations between axial stiffness estimated from linear analysis and yield as well as post‐yield parameters from nonlinear analysis were investigated from in vivo μ MR images of the distal tibia (N = 20; ages: 58–84) and radius (N = 20; ages: 50–75).

Results:

All simulations were completed in 1 h or less for 61 strain levels using a desktop computer (dual quad‐core Xeon 3.16 GHz CPUs equipped with 40 GB of RAM). Although yield stress and ultimate stress correlated strongly (R2 > 0.95, p < 0.001) with axial stiffness, toughness correlated moderately at the distal tibia (R2 = 0.81, p < 0.001) and only weakly at the distal radius (R2 = 0.34, p = 0.007). Further, toughness was found to vary by up to 16% for bone of very similar axial stiffness (<2%).

Conclusions:

The work demonstrates the practicality of nonlinearμ FE simulations at in vivo μMRI resolution, as well as its potential for providing additional information beyond that obtainable from linear analysis. The data suggest that a direct assessment of toughness may provide information not captured by stiffness.
Signaling Mechanisms in Mammalian Myoblast Fusion
Authors: Hindi Sajedah M. , Tajrishi Marjan M. , Kumar Ashok
Published: April 2013

A number of signaling pathways coordinate the development and repair of muscle fibers.
Preclinical Pharmacokinetics and Tissue Distribution of Long-Acting Nanoformulated Antiretroviral Therapy
Authors: Gautam Nagsen , Roy Upal , Balkundi Shantanu , Puligujja Pavan , Guo Dongwei , Smith Nathan , Liu Xin-Ming , Lamberty Benjamin , Morsey Brenda , Fox Howard S. , McMillan JoEllyn , Gendelman Howard E. , Alnouti Yazen
Published: April 2013

Long-acting injectable nanoformulated antiretroviral therapy (nanoART) was developed with the explicit goal of improving medicine compliance and for drug targeting of viral tissue reservoirs. Prior nanoART studies completed in humanized virus-infected mice demonstrated sustained antiretroviral responses. However, the pharmacokinetics (PK) and tissue distribution of nanoART were not characterized. To this end, the PK and tissue distribution of nanoformulated atazanavir (ATV) and ritonavir (RTV) injected subcutaneously or intramuscularly in mice and monkeys were evaluated. Fourteen days after injection, ATV and RTV levels were up to 13-, 41-, and 4,500-fold higher than those resulting from native-drug administration in plasma, tissues, and at the site of injection, respectively. At nanoART doses of 10, 50, 100, and 250 mg/kg of body weight, relationships of more- and less-than-proportional increases in plasma and tissue levels with dose increases were demonstrated with ATV and RTV. Multiple-dose regimens showed serum and tissue concentrations up to 270-fold higher than native-drug concentrations throughout 8 weeks of study. Importantly, nanoART was localized in nonlysosomal compartments in tissue macrophages, creating intracellular depot sites. Reflective data were obtained in representative rhesus macaque studies. We conclude that nanoART demonstrates blood and tissue antiretroviral drug levels that are enhanced compared to those of native drugs. The sustained and enhanced PK profile of nanoART is, at least in part, the result of the sustained release of ATV and RTV from tissue macrophases and at the site of injection.
Draft Genome Sequence of Stenotrophomonas maltophilia Strain EPM1, Found in Association with a Culture of the Human Parasite Giardia duodenalis
Authors: Sassera Davide , Leardini Iacopo , Villa Laura , Comandatore Francesco , Carta Claudio , Almeida André , do Céu Sousa Maria , Gaiarsa Stefano , Marone Piero , Pozio Edoardo , Cacciò Simone M.
Published: April 2013

We report the draft genome sequence of the
Stenotrophomonas maltophilia
strain EPM1, found in association with a culture of
Giardia duodenalis
. The draft genome sequence of
S. maltophilia
strain EPM1, obtained with Roche 454 GS-FLX Titanium technology, is composed of 19 contigs totaling 4,785,869 bp, with a G+C content of 66.37%.
Understanding Barriers to Borrelia burgdorferi Dissemination during Infection Using Massively Parallel Sequencing
Authors: Troy Erin B. , Lin Tao , Gao Lihui , Lazinski David W. , Camilli Andrew , Norris Steven J. , Hu Linden T.
Published: April 2013

Borrelia burgdorferi
is an invasive spirochete that can cause acute and chronic infections in the skin, heart, joints, and central nervous system of infected mammalian hosts. Little is understood about where the bacteria encounter the strongest barriers to infection and how different components of the host immune system influence the population as the infection progresses. To identify population bottlenecks in a murine host, we utilized Tn-seq to monitor the composition of mixed populations of
B. burgdorferi
during infection. Both wild-type mice and mice lacking the Toll-like receptor adapter molecule MyD88 were infected with a pool of infectious
B. burgdorferi
transposon mutants with insertions in the same gene. At multiple time points postinfection, bacteria were isolated from the mice and the compositions of the
B. burgdorferi
populations at the injection site and in distal tissues determined. We identified a population bottleneck at the site of infection that significantly altered the composition of the population. The magnitude of this bottleneck was reduced in MyD88
−/−
mice, indicating a role for innate immunity in limiting early establishment of
B. burgdorferi
infection. There is not a significant bottleneck during the colonization of distal tissues, suggesting that founder effects are limited and there is not a strict limitation on the number of organisms able to initiate populations at distal sites. These findings further our understanding of the interactions between
B. burgdorferi
and its murine host in the establishment of infection and dissemination of the organism.
Geodetic Constants: Data Concerning the Interior of the Earth
Authors: Birch Francis
Published: April 2013

ContentsPageTable 81. Figure of the Earth’s surface1042. Gravity at the surface; mass, mean density, moment of inertia1043. Pressure, density, acceleration of gravity and ellipticity of layers of equal density in the Earth1054. The Earth’s core106

1. Benfield, Z. f. Geophys. 13, 157, 1937.

2. Birch, Bull. Seism. Soc. Amer. 29, 463, 1939.

3. Bullen, M. N. R. A. S. Geophys. Supp. 3, 395, 1936.

4. Bullen, Trans. Roy. Soc. New Zealand, 67, 122, 1937.

5. Bullen, idem, 69, 188, 1939.

6. Bullen, Bull. Seism. Soc. Amer. 30, 235, 1940.

7. Gutenberg and Richter, Beitr. z. Geophys. 54, 94, 1939.

8. Gutenberg and Richter, M. N. R. A. S. Geophys. Supp. 4, 363, 1938.

9. Jeffreys, M. N. R. A. S. Geophys. Supp. 4, 537, 548 and 594, 1939.

10. Lambert, The Internal Constitution of the Earth, Chap. 13, McGraw-Hill, New York, 1939.

11. Olczak, Acta Astron. 3, 81, 1938.

12. Williamson and Adams, J. Washington Acad. Sci. 13, 413, 1923.

Table 8–1.—Figure of the Earth’s Surface

(Ref. 10) Semi-axes of International Ellipsoid of Reference (1924): Equatorial, a = 6378.388 km.Polar, c = 6356.912 km.Radius of sphere of equal volume, α0 = 6371 km.Ellipticity of surface, (a – c)/a = 1/297 = 0.00337. (For ellipticity of internal levels, see Table 8–3.)Quadrant of a meridian = 10,002.288 km.Quadrant of the equator = 10,019.148 km.Area of surface = 5.101 × 1018 cm.2Volume = 1.0832
Viscosity
Authors: Birch Francis , Dane E. B.
Published: April 2013

ContentsPageTable 101. Viscosity of certain mineral and rock glasses1332. Viscosity in the system orthoclase-albite1363. Viscosity in the system diopside-albite-anorthite1364. Viscosity computed from field measurements1365. Effect of pressure upon viscosity137

According to Newton’s law of fluid friction, the tangential or shearing stress in a liquid in motion is proportional to the rate of change, with time, of the angle of shear. Real liquids may be divided into two categories: “Newtonian” or “viscous” liquids, for which the factor of proportionality, the “viscosity,” is independent of the “rate of shear”; and “non-Newtonian” liquids, for which the factor depends upon this rate. The “Newtonian” behavior of many ordinary liquids, and of some glasses, has been verified for considerable ranges of shear rate. “Non-Newtonian” behavior has been observed for such materials as certain colloidal solutions, asphalt, and other bituminous products; no single value of “viscosity” is sufficient to describe the flow of such materials. (See also Section 9.) If the stress is measured in dynes × cm.−2, and the rate of shear in radians × sec.−1, the viscosity will be given in dyne × sec. × cm.−2 or the equivalent unit, gram × sec.−1 × cm. −1 This unit is called the poise and is used in the tables in this section.

The viscosity of a given material depends upon the pressure and temperature. Other factors of great importance for geological applications remain to be investigated, such as the effect of dissolved gases . . .
Density at High Temperature; Thermal Expansion
Authors: Dane E. B.
Published: April 2013

ContentsPageTable 31. Thermal expansion of single crystals301.1. Thermal expansion of quartz352. Density at high temperature, liquid and crystalline states363. Density and thermal expansion of a few commercial glasses at high temperature374. Thermal expansion of rocks37

The following tables contain the expansion of a selected list of naturally occurring substances, together with a few artificial ones like steel and silica glass for comparison. All the minerals for which high-temperature data are available are included, although some are of more interest as refractories than in geology. A number of other minerals whose expansions have been measured only to 100°C. or less are also included; a much more complete list of these latter will, however, be found in the International Critical Tables. In view of the many irregularities which have been found, extrapolation from these low temperatures to those of greater geologic interest is unsafe.

The tables list the total expansion from 20°C., in per cent of the length or volume at 20°C. The nomenclature in regard to axes, angles, etc., follows Dana’s Textbook of mineralogy (John Wiley and Sons, New York, 1922). For isometric substances only the linear expansion is given; the volumetric expansion may be computed to a close approximation by multiplying the linear expansion by three. For the other crystallographic classes, both linear and volumetric values are quoted. With tetragonal and hexagonal minerals, a change of temperature distorts an original sphere into an ellipsoid of revolution so that . . .
Observed Temperatures in the Earth’s Crust
Authors: Spicer H. Cecil
Published: April 2013

ContentsPageTable 191. Earth temperatures in the United States2812. Temperatures in foreign wells and mines2863. Temperature gradient, conductivity, and heat flow in South Africa2914. Heat flow in Great Britain2925. Maximum observed temperatures of lava at volcanic vents292

The tables in this section are based on those of Van Orstrand [1]; data which have appeared since the preparation of Van Orstrand’s tables are inserted where possible [2, 3, 4], or are presented as separate tables [5, 6], The observations of temperature in the mines, deep wells, and bore holes selected by Van Orstrand have been reduced by the method of least squares to equations of the form, T=a+bxwhere T is the temperature (°C.) at the depth x kilometers. For observations made in the United States, this reduction has been made for three ranges of depth: from 30.5 to 305 meters (100 to 1000 feet), from 30.5 meters to the deepest observation, and from 610 meters (2000 feet) to the deepest observation. These intervals will only accidentally bear any relation to the geological structure or stratigraphy. The constant a is the extrapolated surface soil temperature and is generally within a few degrees of the mean annual air temperature. The tabulated values of a are for the range, 30.5 to 305 meters; the values of a for the other ranges of depth, except in a few instances, are within less than 5 degrees of this value. The coefficient 6 is the mean . . .
Magnetic Properties of Rocks
Authors: Slichter L. B.
Published: April 2013

ContentsPageTable 201. Magnetic susceptibility of magnetite2952. Susceptibility of magnetic minerals2963. Range of magnetic susceptibility in major rock types2964. Susceptibility and remanent magnetization of rocks297

Magnetic susceptibility of magnetite and of ferromagnetic minerals.—Magnetite, by reason of its relatively high magnetic susceptibility and wide distribution, is easily the most important ferromagnetic mineral. Indeed, the value of the magnetic susceptibility of a rock is generally determined solely by its contained magnetite. The other ferromagnetic minerals are few in number and of rarer occurrence. The most important ones are pyrrhotite, ilmenite, specularite, franklinite, and cubanite.

In Table 20–1 are listed values of the magnetic susceptibility of magnetite. These values spread over a wide range and are dependent not only upon the specimen itself but also upon the intensity of the magnetizing field. In natural, large-scale occurrences of magnetite, such as ore bodies, the extremely high values of susceptibility found by Weiss [25] for single crystals and by Steinmetz [26] are rarely, if ever, observed. A value of about .3 is usually appropriate, but exceptions must be expected, since the susceptibility of magnetite in common with that of other ferromagnetic substances is sensitive to small changes in composition or structure.

In Table 20–2 are listed measured susceptibilities for other ferromagnetic minerals. It will be noted that the susceptibility of magnetite is at least ten times that of other minerals.

Magnetic susceptibility of rocks.—Published measurements of the magnetic susceptibility of rocks are . . .
Women's responses to information about overdiagnosis in the UK breast cancer screening programme: a qualitative study
Authors: Waller Jo , Douglas Elaine , Whitaker Katriina L , Wardle Jane
Published: April 2013

Objectives

To explore the influence of overdiagnosis information on women's decisions about mammography.

Design

A qualitative focus group study with purposive sampling and thematic analysis, in which overdiagnosis information was presented.

Setting

Community and university settings in London.

Participants

40 women within the breast screening age range (50–71 years) including attenders and non-attenders were recruited using a recruitment agency as well as convenience sampling methods.

Results

Women expressed surprise at the possible extent of overdiagnosis and recognised the information as important, although many struggled to interpret the numerical data. Overdiagnosis was viewed as less-personally relevant than the possibility of ‘under diagnosis’ (false negatives), and often considered to be an issue for follow-up care decisions rather than screening participation. Women also expressed concern that information on overdiagnosis could deter others from attending screening, although they rarely saw it as a deterrent. After discussing overdiagnosis, few women felt that they would make different decisions about breast screening in the future.

Conclusions

Women regard it as important to be informed about overdiagnosis to get a complete picture of the risks and benefits of mammography, but the results of this study indicate that understanding overdiagnosis may not always influence women's attitudes towards participation in breast screening. The results also highlight the challenge of communicating the individual significance of information derived from population-level modelling.
Effects of exenatide and metformin in combination on some adipocytokine levels: a comparison with metformin monotherapy
Authors: Derosa Giuseppe , Cicero Arrigo F.G. , Franzetti Ivano G. , Querci Fabrizio , Carbone Anna , Ciccarelli Leonardina , D’Angelo Angela , Fogari Elena , Maffioli Pamela
Published: April 2013

The aim of this study was to evaluate the effects of exenatide on levels of serum adipocytokines and on β-cell function. The study was conducted between 2008 and 2012. After a run-in period with metformin, 174 patients with type-2 diabetes were randomly distributed to either a group receiving exenatide at 10 μg twice daily, or a group receiving the placebo, for 12 months. We evaluated body mass index (BMI), blood pressure, glycemic control, lipid profile, fasting plasma insulin (FPI), HOMA-IR, HOMA-β, fasting plasma proinsulin (FPPr), proinsulin : fasting plasma insulin ratio (Pr/FPI ratio), C-peptide, glucagon, retinol binding protein-4 (RBP-4), visfatin, omentin-1, and microalbuminuria. We used ELISA methods to assess the various parameters. Patients also underwent a combined euglycemic-hyperinsulinemic and hyperglycemic clamp, with subsequent arginine stimulation. After 12 months, a combination of exenatide and metformin produced a better decrease in body mass, BMI, glycemic control, FPI, FPPr, FPPr/FPI ratio, HOMA-IR, and glucagon level. Treatment with exenatide + metformin was superior to the placebo + metformin in increasing HOMA-β, C-peptide, and β-cell function. Significant negative correlations were found between M value, an index of insulin sensitivity, and measured adipocytokines. In conclusion, the combination of exenatide + metformin plays a role in improving some adipocytokine levels, and is better than metformin alone. The significant negative correlation between M value and measured adipocytokines is another confirmation of the positive effects linked to the improvement in insulin sensitivity.
Monitoring and estimating drought-induced impacts on forest structure, growth, function, and ecosystem services using remote-sensing data: recent progress and future challenges
Authors: Zhang Yao , Peng Changhui , Li Weizhong , Fang Xiuqin , Zhang Tinglong , Zhu Qiuan , Chen Huai , Zhao Pengxiang
Published: April 2013

Alongside global warming, droughts are expected to increase in frequency, severity, and extent in the near future, which will likely result in significant impacts on forest growth, production, structure, composition, and ecosystem services. However, due to spatial and temporal characteristics, it is difficult to monitor and assess the potential effects of droughts. Remote sensing can provide an effective way to obtain real-time conditions of forests affected by drought and offer a range of spatial and temporal insights into drought-induced changes to forest ecosystem structure, function, and services. Remote sensing is rapidly developing as more satellites are launched. In situ and remotely sensed data fusion techniques have achieved notable success in assessing drought-induced damage to forests and carbon cycles. Even so, constraints still exist when using satellite data. The objectives of this review are to (1) briefly review existing data sources and methods of remote sensing; (2) synthesize current applications and contributions of remote sensing in monitoring and estimating impacts of droughts on forest ecosystems; and (3) highlight research gaps and future challenges.
AN EFFICIENT CURRENT REGULATOR FOR MULTILEVEL VOLTAGE SOURCE CONVERTER BASED ON A SIMPLE ANALOG CONTROL CIRCUIT
Authors: ELNADY A.
Published: April 2013

This paper presents an innovative driver circuit for a new current regulator of the multilevel inverters. The proposed regulator has a PI controller to guarantee the optimum tracking for the reference current. This proposed regulator has the advantage of integration between the PI controller and the multicarrier switching operation. This regulator fits the operation of multilevel and cascaded converters. The suggested current regulator is compared with several existing current regulators of the multilevel and cascaded converters. The performance of the proposed regulator is verified using simulation results in comparison with the performance of the common existing current regulators for the multilevel inverter. Moreover, this paper shows the performance of the new regulator in power system applications.
SOME CRITERIA FOR THE FINITENESS OF COZERO-DIVISOR GRAPHS
Authors: AKBARI S. , KHOJASTEH S.
Published: April 2013

Let R be a commutative ring with unity. The cozero-divisor graph of R denoted by Γ'(R) is a graph with the vertex set W*(R), where W*(R) is the set of all nonzero and non-unit elements of R, and two distinct vertices a and b are adjacent if and only if a ∉ Rb and b ∉ Ra, where Rc is the ideal generated by the element c in R. Let α(Γ'(R)) and γ(Γ'(R)) denote the independence number and the domination number of Γ'(R), respectively. In this paper, we prove that if α(Γ'(R)) is finite, then R is Artinian if and only if R is Noetherian. Also, we prove that if α(Γ'(R)) is finite, then R/P is finite, for every prime ideal P. Moreover, we prove that if R is a Noetherian ring, γ(Γ'(R)) is finite and Γ'(R) has at least one isolated vertex, then J(R) = N(R). We show that if R is a commutative Noetherian local ring, γ(Γ'(R)) is finite and Γ'(R) has at least one isolated vertex, then R is a finite ring. Among other results, we prove that if R is a commutative ring and the maximum degree of Γ'(R) is finite and positive, then R is a finite ring.
A CONSTRUCTION OF RIGHT ARTINIAN RIGHT SERIAL RINGS
Authors: SINGH SURJEET
Published: April 2013

A ring R is said to be right serial, if it is a direct sum of right ideals which are uniserial. A ring that is right serial need not be left serial. Right artinian, right serial ring naturally arise in the study of artinian rings satisfying certain conditions. For example, if an artinian ring R is such that all finitely generated indecomposable right R-modules are uniform or all finitely generated indecomposable left R-modules are local, then R is right serial. Such rings have been studied by many authors including Ivanov, Singh and Bleehed, and Tachikawa. In this paper, a universal construction of a class of indecomposable, non-local, basic, right artinian, right serial rings is given. The construction depends on a right artinian, right serial ring generating system X, which gives rise to a tensor ring T(L). It is proved that any basic right artinian, right serial ring is a homomorphic image of one such T(L).
ON CONJUGATE-ℨ-PERMUTABLE SUBGROUPS OF FINITE GROUPS
Authors: HELIEL A. A. , Al-GAFRI T.M.
Published: April 2013

Let ℨ be a complete set of Sylow subgroups of a finite group G, that is, for each prime p dividing the order of G, ℨ contains exactly one and only one Sylow p-subgroup of G, say Gp. Let C be a nonempty subset of G. A subgroup H of G is said to be C-ℨ-permutable (conjugate-ℨ-permutable) subgroup of G if there exists some x ∈ C such that HxGp = GpHx, for all Gp ∈ ℨ. We investigate the structure of the finite group G under the assumption that certain subgroups of prime power orders of G are C-ℨ-permutable (conjugate-ℨ-permutable) subgroups of G. Our results improve and generalize several results in the literature.
FUSION RULES AND COMPLETE REDUCIBILITY OF CERTAIN MODULES FOR AFFINE LIE ALGEBRAS
Authors: ADAMOVIĆ DRAŽEN , PERŠE OZREN
Published: April 2013

We develop a new method for obtaining branching rules for affine Kac–Moody Lie algebras at negative integer levels. This method uses fusion rules for vertex operator algebras of affine type. We prove that an infinite family of ordinary modules for affine vertex algebra of type A investigated in our previous paper J. Algebra319 (2008) 2434–2450, is closed under fusion. Then, we apply these fusion rules on explicit bosonic realization of level -1 modules for the affine Lie algebra of type [Formula: see text], obtain a new proof of complete reducibility for these representations, and the corresponding decomposition for ℓ ≥ 3. We also obtain the complete reducibility of the associated level -1 modules for affine Lie algebra of type [Formula: see text]. Next, we notice that the category of [Formula: see text] modules at level -2ℓ + 3 has the isomorphic fusion algebra. This enables us to decompose certain [Formula: see text] and [Formula: see text]-modules at negative levels.
A NOTE ON SELF-SMALL MODULES OVER RM-DOMAINS
Authors: ALBRECHT U. , BREAZ S.
Published: April 2013

This paper provides two new characterizations of RM-domains, i.e. domains satisfying the restricted minimum condition. A Noetherian domain is a RM-domain if and only if every torsion module is a direct sum of submodules whose cyclic submodules have finite length and homogeneous composition series. We show that this occurs exactly if all self-small torsion modules are finitely generated.
THE PRE-LIE OPERAD AS A DEFORMATION OF NAP
Authors: SAÏDI ABDELLATIF
Published: April 2013

We introduce current-preserving operads, which are colored operads together with an additive semigroup structure on the set G of colors. This is the natural framework in which types of G-graded algebras can be dealt with. As an example of application, we deform the NAP operad into the pre-Lie operad in this context, where G is the additive semigroup of positive integers. More precisely, we give a family [Formula: see text] of current-preserving operads, depending on a scalar parameter λ, such that [Formula: see text], respectively, [Formula: see text], is the current-preserving operad governing graded NAP (respectively, pre-Lie) algebras.
ENTANGLEMENT DEGRADATION IN THE PRESENCE OF (4 + n)-DIMENSIONAL SCHWARZSCHILD BLACK HOLE
Authors: PARK DAEKIL
Published: April 2013

In this paper, we compute the various bipartite quantum correlations in the presence of the (4 + n)-dimensional Schwarzschild black hole. In particular, we focus on the n-dependence of various bosonic bipartite entanglements. For the case between Alice and Rob, where the former is free falling observer and the latter is at the near-horizon region, the quantum correlation is degraded compared to the case in the absence of the black hole. The degradation rate increases with decreasing n. We also compute the physically inaccessible correlations. It is found that there is no creation of quantum correlation between Alice and AntiRob. For the case between Rob and AntiRob the quantum entanglement is created although they are separated in the causally disconnected regions. It is found that contrary to the physically accessible correlation the entanglement between Rob and AntiRob decreases with increasing n.
RESEARCH OF HEAT TRANSFER AND PRESSURE DROP CHARACTERISTIC OF CONCAVO-CONVEX PLATE
Authors: KANEKO AKIRA , KATSUTA MASAFUMI , HAMANO YUKI
Published: April 2013

For an automobile air-conditioning system, performance improvement of the heat exchanger is needed to fit in the change of refrigerant and heat pump system. In this study, the heat transfer and pressure drop characteristic of air flow between parallel plates with concavity and convexity is grasped, and the possibility of using a fin-less heat exchanger is considered analytically. And it has been shown that a fin-less heat exchanger has the possibility of increasing performance compared to a conventional heat exchanger, which uses a corrugated louver fin.