bluuebunny/crossref_metadata_2025 huggingface dataset:
A Fréchet law and an Erdős–Philipp law for maximal cuspidal windings
Authors: JAERISCH JOHANNES , KESSEBÖHMER MARC , STRATMANN BERND O.
Published: July 2012

In this paper we establish a Fréchet law for maximal cuspidal windings of the geodesic flow on a Riemannian surface associated with an arbitrary finitely generated, essentially free Fuchsian group with parabolic elements. This result extends previous work by Galambos and Dolgopyat and is obtained by applying extreme value theory. Subsequently, we show that this law gives rise to an Erdős–Philipp law and to various generalized Khintchine-type results for maximal cuspidal windings. These results strengthen previous results by Sullivan, Stratmann and Velani for Kleinian groups, and extend earlier work by Philipp on continued fractions, which was inspired by a conjecture of Erdős.
Relativistic self-focusing of super-Gaussian laser beam in plasma with transverse magneticfield
Authors: Gill Tarsem Singh , Mahajan Ranju , Kaur Ravinder , Gupta Suhail
Published: July 2012

This paper presents an investigation of a self-consistent, theoretical model, which explains the ring formation in a super-Gaussian laser beam propagating in plasma with transverse magnetic field, characterized by relativistic nonlinearity. Higher order terms (up to r4) in the expansion of the dielectric function and the eikonal have been taken into account. The condition for the formation of a dark and bright ring has been used to study focusing/defocusing of the beam. It is seen that inclusion of higher order terms does significantly affect the dependence of beam width parameter on the distance of propagation. Self-focusing of super-Gaussian beam is studied at various values of super-Gaussian coefficient, m and magnetic field. Further, we have studied some distinct features of critical power curves for varying values of magnetic field.
Clinical response to arginine vasopressin therapy after paediatric cardiac surgery
Authors: Mastropietro Christopher W. , Davalos Maria C. , Seshadri Shivaprakash , Walters Henry L. , Delius Ralph E.
Published: July 2012

Objective

To describe the haemodynamic response of children who receive arginine vasopressin for haemodynamic instability after cardiac surgery and to identify clinical variables associated with a favourable response.

Materials and Methods

We reviewed patients less than or equal to 6 years undergoing open heart surgery in our institution between January, 2009 and July, 2010 who received arginine vasopressin during the first 7 days post operation. Favourable responders were defined as those in whom blood pressure was increased or maintained and catecholamine score was decreased, or blood pressure was increased by greater than or equal to 10% of baseline and catecholamine score was unchanged at 6 hours following arginine vasopressin initiation.

Results

Of the 34 patients identified, 17 (50%) patients responded favourably to arginine vasopressin. At 6 hours, the mean blood pressure was increased by 32.2% in responders as compared with 4.6% in non-responders, with a p-value less than 0.001. The mean catecholamine score decreased by 30.1% in responders and increased by 7.6% in non-responders, with a p-value less than 0.001. Anthropometric, demographic, and intra-operative variables were similar in both groups, as was maximum dose of arginine vasopressin. The median time after arrival to the intensive care unit at which arginine vasopressin was initiated, however, was later in those who responded, 20 hours as compared with those who did not, 6 hours, with a p-value equal to 0.032.

Conclusions

Arginine vasopressin therapy led to haemodynamic improvement in only half of the children in this study, and improvement was more likely to occur if arginine vasopressin was initiated after the post-operative night.
Comparison of thermodynamic stabilities and mechanical properties of CO2, SiO2, and GeO2 polymorphs by first-principles calculations
Authors: Ledyastuti Mia , Liang Yunfeng , Miranda Caetano R. , Matsuoka Toshifumi
Published: July 2012

The recent discovery that molecular CO2 transforms under compression into carbon four-coordinated, 3-dimensional network solid phases has generated considerable interests on possible new phases in the fourth-main-group elemental oxides. Based on density-functional theory calculations, we have investigated the thermodynamic stability, mechanical properties and electronic structure of proposed guest-free clathrates, quartz and cristobalite phases for CO2, SiO2, and GeO2, and the dry ice phase for CO2. It was predicted that a GeO2 clathrate, likely a semiconductor, could be synthesized presumably with some suitable guest molecules. The hypothetical CO2 guest-free clathrate phase was found hardly to be formed due to the large energy difference with respect to the other polymorphs. This phase is unstable at all pressures, which is also implied by its different electronic structure in comparison with SiO2 and GeO2. Finally, the SiO2 clathrate presents a uniquely high bulk modulus, which is higher than that of quartz and three times of the experimental data, might not be a weak point of ab-initio calculations such as pseudopotentials, correlation functional etc., instead it can be readily understood by the constraint as imposed by the high symmetry. Either temperature or an “exhausted” relaxation (without any symmetry constraint) can remedy this problem.
Kinetic-theory-based model of dense granular flows down inclined planes
Authors: Lee Cheng-Hsien , Huang Ching-Jer
Published: July 2012

This work extends a continuum model of sheared granular material comprising two-dimensional disks [C. H. Lee and C. J. Huang, Phys. Fluids 22, 043307 (2010)10.1063/1.3400203] to elucidate the dynamics of three-dimensional spheres. The proposed model is applied to investigate dense granular flows down an inclined plane. In the model, stress has a static component and a kinetic component. The constitutive model for shear stress reduces to the Bagnold model when the diffusion of granular temperature is small. The predicted rheological characteristics are identical to those observed in the preceding experiments and numerical simulations, validating the present model. The predicted rheological characteristics reveal that dense granular flows down an inclined plane are characterized by three special angles that determine the phase diagram. The predicted thick granular flow on an inclined plane exhibits the Bagnold velocity profile and a uniform volume fraction throughout its depth. The governing equation of granular temperature is simplified and solved analytically. The proposed shear granular flow model is also solved completely using the finite volume method. The predicted velocity and volume fraction agree very well with previous discretely simulated results. This work also proposes an equation for determining the characteristic length of dense granular flows and shows that its static component is close to the stopping height.
Long wavelength gradient drift instability in Hall plasma devices. I. Fluid theory
Authors: Frias Winston , Smolyakov Andrei I. , Kaganovich Igor D. , Raitses Yevgeny
Published: July 2012

The problem of long wavelength instabilities in Hall thruster plasmas is revisited. A fluid model of the instabilities driven by the E0×B drift in plasmas with gradients of density, electron temperature, and magnetic field is proposed. It is shown that full account of compressibility of the electron flow in inhomogeneous magnetic field leads to quantitative modifications of earlier obtained instability criteria and characteristics of unstable modes. Modification of the stability criteria due to finite temperature fluctuations is investigated.
Numerical simulation of carbon arc discharge for nanoparticle synthesis
Authors: Kundrapu M. , Keidar M.
Published: July 2012

Arc discharge with catalyst-filled carbon anode in helium background was used for the synthesis of carbon nanoparticles. In this paper, we present the results of numerical simulation of carbon arc discharges with arc current varying from 10 A to 100 A in a background gas pressure of 68 kPa. Anode sublimation rate and current voltage characteristics are compared with experiments. Distribution of temperature and species density, which is important for the estimation of the growth of nanoparticles, is obtained. The probable location of nanoparticle growth region is identified based on the temperature range for the formation of catalyst clusters.
Tungsten silicide films for microwave kinetic inductance detectors
Authors: Cecil Thomas , Miceli Antonino , Quaranta Orlando , Liu Chian , Rosenmann Daniel , McHugh Sean , Mazin Benjamin
Published: July 2012

Microwave kinetic inductance detectors provide highly multiplexed arrays of detectors that can be configured to operate from the sub-millimeter to the x-ray regime. We have examined two tungsten silicide alloys (W5Si3 and WSi2), which are dense alloys that provide a critical temperature tunable with composition, large kinetic inductance fraction, and high normal-state resistivity. We have fabricated superconducting resonators and provide measurement data on critical temperature, surface resistance, quality factor, noise, and quasiparticles lifetime. Tungsten silicide appears to be promising for microwave kinetic inductance detectors.
Complementary metal–oxide–semiconductor compatible high efficiency subwavelength grating couplers for silicon integrated photonics
Authors: Xu Xiaochuan , Subbaraman Harish , Covey John , Kwong David , Hosseini Amir , Chen Ray T.
Published: July 2012

We demonstrate a through-etched grating coupler based on subwavelength nanostructure. The grating consists of arrays of 80 nm × 343 nm rectangular air holes, which can be patterned in a single lithography/etch. A peak coupling efficiency of 59% at 1551.6 nm and a 3 dB bandwidth of 60 nm are achieved utilizing the silicon-on-insulator platform with a 1 μm thick buried-oxide layer for transverse electric mode. The performance is comparable to gratings requiring much more complicated fabrication processes.
Communication: Shock adiabat of atomic nitrogen at megabar pressures
Authors: Vorob'ev V. S. , Grushin A. S. , Novikov V. G.
Published: July 2012

We use spherical cellular method combined with a self-consistent density functional approach (quasizone method) to calculate the band structure and bulk properties of atomic nitrogen at megabar pressures and densities 3.2÷3.6 g/cm3. Thermodynamic functions and shock adiabat calculated by this method correspond to recent measurements, showing a sharp increase in pressure along the shock adiabat in this range of densities.
Optimizing performance of layer-by-layer processed polymer solar cells
Authors: Li Hui , Li Yong-Fang , Wang Jizheng
Published: July 2012

Layer-by-layer (LL) process has recently been used to fabricate polymer solar cells (PSCs), Power conversion efficiency (PCE) of LL processed PSCs is currently below 4%. In this paper, we fabricated polymer photovoltaic devices with poly(3-hexylthiophene) (P3HT) as donor and indene-C60 bisadduct as acceptor with LL method. By carefully optimizing donor/acceptor layer thickness and related thermal annealing process, PCE of 5.12% was achieved. The device displays open-circuit voltage (Voc) of 0.886 V, short-circuit current density (Jsc) of 8.21 mA/cm2, and fill factor of 70.4%.
Children's and Adults' Size Estimates at near and Far Distances: A Test of the Perceptual Learning Theory of Size Constancy Development
Authors: Kavšek Michael , Granrud Carl E.
Published: July 2012

This study tested the perceptual learning theory of size constancy development, which proposes that children younger than 9 years are relatively insensitive to monocular cues for distance and size, and that developmental changes in far-distance size estimation result from increasing sensitivity to these cues. This theory predicts that before 10 years, children will make less accurate size judgments at far distances under monocular than under binocular viewing conditions. Five age groups were tested: 5–6, 7–8, 9–10, 19–28, and 50+ years. Participants judged the size of a standard disc, from viewing distances of 6.1 and 61 m, by pointing at 1 of 9 nearby comparison discs. Testing was conducted under both monocular and binocular viewing conditions. Five- to 6-year-olds underestimated object size at the far distance, 7- to 8-, 9- to 10-year-olds, and older adults made size estimates that were close to accurate, and the young adults significantly overestimated size. At the near distance, all age groups underestimated size and no age differences were found. Contrary to predictions from the perceptual learning theory, viewing condition had no significant effect on size estimates.
Study of the jump fire produced by the interaction of two oblique fire fronts. Part 1. Analytical model and validation with no-slope laboratory experiments
Authors: Viegas Domingos X. , Raposo Jorge R. , Davim David A. , Rossa Carlos G.
Published: July 2012

When two fires approach each other, convective and radiative heat transfer processes are greatly enhanced. The interaction between two linear fire fronts making an angle θoi between them is of particular interest as it produces a very rapid advance of their intersection point with intense radiation and convection activity in the space between the fire lines. This fire is designated here as a ‘jump fire’ for when the value of θoi is small, the intersection point of the fire lines can reach unusually high rate of spread values that decrease afterwards in the course of time. A very simple analytical model based on the concept of energy concentration between the fire lines is proposed to explain this behaviour, which in large-scale fires can be of great concern to personnel and property safety. Experimental tests performed at laboratory scale on a horizontal fuel bed confirmed the basic assumptions of the model and provide a framework to extend the present analysis to more general conditions, namely to explain the behaviour of real fires. Given the rapid changes in fire behaviour, ‘jump fires’ can be considered as a form of extreme fire behaviour.
Do educational backgrounds make a difference?
Authors: Zhou Jing , Jin Lixian
Published: July 2012

For decades there has been a debate about whether parents with different socioeconomic status have differential influences on their children’s language development. This study focuses on the features of language use of Mandarin-speaking mothers with different educational backgrounds in interaction with their 3–6 year old children to explore the similarities and differences between the mothers’ communication with their children. Data were collected from videotaped semi-structured mother–child interactions among different age groups. The main research finding reveals that the communicative acts of these Chinese mothers are similar at the levels of social interchange and the speech act; the common types of communicative acts show a cultural consistency among Chinese mothers in interacting with their young children. However, the language inputs of mothers of the two differing social groups show significant differences on linguistic productivity, vocabulary measurement and pragmatic flexibility. These findings are discussed in the context of the role of mothers’ input in language development.
Chinese preschool children’s comprehension of a picture storybook
Authors: Li Linhui , Zhou Jing , Liu Baogen , Gao Xiaomei
Published: July 2012

This paper explored 3 to 6 year old Chinese children’s comprehension of a picture storybook The Very Hungry Caterpillar. The results show: (1) Chinese children’s understanding of images, actions and characters’ states improves with age; (2) Children develop their understanding of images first, followed by actions and then characters’ states; (3) It is easier for children to understand images prominent in pictures than those not prominent in pictures or containing culture-specific information with which children are not familiar, actions represented directly through relationship of different images than those actions which require making connection with preceding and following pictures, and characters’ states represented by visible information such as size and colour than those less visible or age-appropriate.
Epistasis between mutations is host-dependent for an RNA virus
Authors: Lalić Jasna , Elena Santiago F.
Published: July 2012

How, and to what extent, does the environment influence the way mutations interact? Do environmental changes affect both the sign and the magnitude of epistasis? Are there any correlations between environments in the variability, sign or magnitude of epistasis? Very few studies have tackled these questions. Here, we addressed them in the context of viral emergence. Most emerging viruses are RNA viruses with small genomes, overlapping reading frames and multifunctional proteins for which epistasis is abundant. Understanding the effect of host species in the sign and magnitude of epistasis will provide insights into the evolutionary ecology of infectious diseases and the predictability of viral emergence.
Molecular evidence for an Asian origin of monitor lizards followed by Tertiary dispersals to Africa and Australasia
Authors: Vidal Nicolas , Marin Julie , Sassi Julia , Battistuzzi Fabia U. , Donnellan Steve , Fitch Alison J. , Fry Bryan G. , Vonk Freek J. , Rodriguez de la Vega Ricardo C. , Couloux Arnaud , Hedges S. Blair
Published: July 2012

Monitor lizards are emblematic reptiles that are widely distributed in the Old World. Although relatively well studied in vertebrate research, their biogeographic history is still controversial. We constructed a molecular dataset for 54 anguimorph species, including representatives of all families with detailed sampling of the Varanidae (38 species). Our results are consistent with an Asian origin of the Varanidae followed by a dispersal to Africa 41 (49–33) Ma, possibly via an Iranian route. Another major event was the dispersal of monitors to Australia in the Late Eocene–Oligocene 32 (39–26) Ma. This divergence estimate adds to the suggestion that Australia was colonized by several squamate lineages prior to the collision of the Australian plate with the Asian plate starting 25 Ma.
Raiders from the sky: slavemaker founding queens select for aggressive host colonies
Authors: Pamminger Tobias , Modlmeier Andreas P. , Suette Stefan , Pennings Pleuni S. , Foitzik Susanne
Published: July 2012

Reciprocal selection pressures in host–parasite systems drive coevolutionary arms races that lead to advanced adaptations in both opponents. In the interactions between social parasites and their hosts, aggression is one of the major behavioural traits under selection. In a field manipulation, we aimed to disentangle the impact of slavemaking ants and nest density on aggression of
Temnothorax longispinosus
ants. An early slavemaker mating flight provided us with the unique opportunity to study the influence of host aggression and demography on founding decisions and success. We discovered that parasite queens avoided colony foundation in parasitized areas and were able to capture more brood from less aggressive host colonies. Host colony aggression remained consistent over the two-month experiment, but did not respond to our manipulation. However, as one-fifth of all host colonies were successfully invaded by parasite queens, slavemaker nest foundation acts as a strong selection event selecting for high aggression in host colonies.
New Thermal Management Systems for Data Centers
Authors: Ouchi Mayumi , Abe Yoshiyuki , Fukagaya Masato , Kitagawa Takashi , Ohta Haruhiko , Shinmoto Yasuhisa , Sato Masahide , Iimura Ken-ichi
Published: July 2012

Energy consumption in data centers has seen a drastic increase in recent years. In data centers, server racks are cooled down in an indirect way by air-conditioning systems installed to cool the entire server room. This air cooling method is inefficient as information technology (IT) equipment is insufficiently cooled down, whereas the room is overcooled. The development of countermeasures for heat generated by IT equipment is one of the urgent tasks to be accomplished. We, therefore, proposed new liquid cooling systems in which IT equipment is cooled down directly and exhaust heat is not radiated into the server room. Three cooling methods have been developed simultaneously. Two of them involve direct cooling; a cooling jacket is directly attached to the heat source (or CPU in this case) and a single-phase heat exchanger or a two-phase heat exchanger is used as the cooling jacket. The other method involves indirect cooling; heat generated by CPU is transported to the outside of the chassis through flat heat pipes and the condensation sections of the heat pipes are cooled down by coolant with liquid manifold. Verification tests have been conducted by using commercial server racks to which these cooling methods are applied while investigating five R&D components that constitute our liquid cooling systems: the single-phase heat exchanger, the two-phase heat exchanger, high performance flat heat pipes, nanofluid technology, and the plug-in connector. As a result, a 44–53% reduction in energy consumption of cooling facilities with the single-phase cooling system and a 42–50% reduction with the flat heat pipe cooling system were realized compared with conventional air cooling system.
Cyclic Viscoplastic-Viscodamage Analysis of Shape Memory Polymers Fibers With Application to Self-Healing Smart Materials
Authors: Shojaei Amir , Li Guoqiang , Voyiadjis George Z.
Published: July 2012

The cold-drawn, programmed shape memory polymer (SMP) fibers show excellent stress recovery property, which promotes their application as mechanical actuators in smart material systems. A full understanding of the thermomechanical-damage responses of these fibers is crucial to minimize the trial-and-error manufacturing processes of these material systems. In this work, a multiscale viscoplastic-viscodamage theory is developed to predict the cyclic mechanical responses of SMP fibers. The proposed viscoplastic theory is based on the governing relations for each of the individual microconstituents and establishes the microscale state of the stress and strain in each of the subphases. These microscale fields are then averaged through the micromechanics framework to demonstrate the macroscale constitutive mechanical behavior. The cyclic loss in the functionality of the SMP fibers is interpreted as the damage process herein, and this cyclic loss of stress recovery property is calibrated to identify the state of the damage. The continuum damage mechanics (CDM) together with a thermodynamic consistent viscodamage theory is incorporated to simulate the damage process. The developed coupled viscoplastic-viscodamage theory provides an excellent correlation between the experimental and simulation results. The cyclic loading-damage analysis in this work relies on the underlying physical facts and accounts for the microstructural changes in each of the micro constituents. The established framework provides a well-structured method to capture the cyclic responses of the SMP fibers, which is of utmost importance for designing the SMP fiber-based smart material systems.
An efficient numerical method for solving the horn equation
Authors: Pyle Robert W.
Published: July 2012

For lossless horns, there are many contours for which exact solutions of the so-called ‘‘Webster’’ horn equation are known. For quantitative work on brass instruments, however, it may be necessary to solve the equation for arbitrary contours, perhaps known only numerically from measurements of existing instruments. The present paper describes a numerical technique that is efficient and accurate. The effects of viscous and thermal damping at the walls of the horn are easily incorporated. Like most numerical methods for solving differential equations, this breaks the length of the horn into a number of smaller pieces. However, the pieces are not quasi-infinitesimal, but are initially as long as a quarter wavelength. The number of pieces is then increased and the error is estimated and reduced in a series of consecutive approximations using a method called ‘‘the deferred approach to the limit.’’ Where an exact solution is known (e.g., lossless exponential or catenoidal horn), results accurate to about six or seven decimal places are easily obtainable when the calculations are carried out with a resolution of about 15 significant figures.
Acoustical characteristics of a 360-degree surround hall
Authors: Bradley John S. , Madaras Gary , Jaffe Chris
Published: July 2012

Boettcher Hall in Denver is a large multipurpose hall with audience seating completely surrounding the stage and has been described as a 360-deg surround hall. Extensive acoustical measurements were carried out to evaluate the characteristics of this hall configuration and to compare it to other halls of more conventional design. Impulse response measurements were made for the 45 combinations of three on-stage source positions and 15 receiver positions distributed throughout the audience seating area. The setup of the hall was representative of a typical unoccupied concert configuration. Measured parameters included octave band values of: reverberation times, early decay times, relative sound levels, and early/late sound ratios. Various measures of spatial impression were also measured including: lateral energy fractions, inter-aural cross correlations, and the newly proposed measure of listener envelopment, the late lateral sound level. Hall average values as well as the spatial variation of acoustical measures are compared to data obtained from a number of other halls. [Work supported by the Concert Hall Research Group.]
An experimental study of the open-end correction coefficient for side branches within an acoustic tube and its application in speech production
Authors: Dang J. , Shadle C. , Suzuki H.
Published: July 2012

The open-end correction coefficient (OECC) for side branches within an acoustic tube was investigated experimentally, and combined with morphological data of the vocal tract to arrive at OECC estimates useful in speech production. A number of mechanical acoustic models were used to examine the effects of the angle of the branch axis, and the proximity of the main tube around the open end of the branch. The results indicate that the OECC (α1) depends on the cross-dimension L of the main tract at the branching point and the branch diameter D (α1=0.414 +0.517⋅log10(L/D2), 0.158<L/D2<6.97). For side branches connected to the main tract by a narrow neck, the OECC of each end of the neck is determined by α2=0.82(1−ξ)/18ξ2−3.1ξ+1, where ξ= the ratio of radius of the neck to that of the adjacent section. Using morphological data of the vocal-tract, the range of appropriate OECC values for estimating accurate vocal-tract transfer function was evaluated. The OECC of the nasopharyngeal port was about 0.8 for the oral-tract side, 0.3–0.6 for the nasal-tract side. For the ostia of the paranasal cavities, the value was ∼0.8 for the cavity side, ∼0 for the nasal-tract side.
Beyond direct path seabottom scatter
Authors: Rogers Andrew , Neumann Peter
Published: July 2012

A great deal of reverberation data collected and processed for scattering strength is truncated such that angles containing energy from fathometer and hybrid eigenray paths are disregarded. This practice has been a result of the common use of plane-wave direct path scattering models, which inherently cannot compute these events. The recent development of the acoustic scattering model SCARAB (scattering reverberation and backscatter) has provided a tool for investigating the information contained in this low grazing angle scatter. Data taken during the Critical Sea Test (CST) initiative has been processed using traditional direct path methods retaining data at scattering angles well below that where fathometer and hybrid path contamination occur. Model to data comparisons have shown excellent agreement, providing new insight into the dominant mechanisms for scattering from the seabottom. Utilization of the low grazing angle fathometer and hybrid paths is found to be critical in defining the physical control mechanisms of seabottom scatter at all angles. [Work supported by ONR.]
Current differential diagnoses and treatment options of vascular occlusions presenting as bilateral thalamic infarcts: a review of the literature
Authors: Agarwal Nitin , Tolia Arpan , Hansberry David Richard , Duffis Ennis Jesus , Barrese James C , Gandhi Chirag D , Prestigiacomo Charles J
Published: July 2012

bilateral thalamic infarctions are rare and usually caused by vascular occlusions. When symptomatic, it is important to make a distinction between different vascular etiologies in order to provide an effective and timely therapeutic response. Clinical presentations may not adequately differentiate between the vascular etiologies alone. It is therefore important to use imaging technologies to distinguish appropriately the origin of the infarct so that proper treatment can be administered. Advanced imaging techniques, such as CT angiography and MR angiography, have proved useful for distinguishing between arterial and venous causes of bithalamic infarctions. Bilateral thalamic venous infarctions can be treated with anticoagulation medication and with thrombolysis in more severe cases. Bilateral thalamic arterial infarctions may be treated with thrombolysis.
Cerebral Venous Thrombosis as an Extrahepatic Manifestation of Acute Anicteric Hepatitis A Infection
Authors: Zis Panagiotis , Kontogeorgi Elli , Karakalos Dimitrios , Pavlopoulou Despoina , Sevastianos Vassilios A.
Published: July 2012

Among the many infective causes of cerebral venous thrombosis (CVT), viral hepatitis has been regarded as a rare associated condition. We report the case of a 31-year-old woman presenting with CVT associated with hepatitis A virus (HAV) infection, outlining probable pathogenic mechanisms. We suggest that hepatitis A serological markers should be routinely included in the investigation of cerebral venous thrombosis of unknown etiology, in nonvaccinated patients with risk factors of a recent HAV exposure.
A Penetrating Stab Wound of the Perianal Area Causing a Combined Rectal and Bladder Injury: One Case Report
Authors: Tazi Mohammed Fadl , Khallouk Abdelhak , Ahallal Youness , Riyach Omar , El Ammari Jalal Eddine , El Fassi Mohammed Jamal , Farih Moulay Hassan
Published: July 2012

Although the management of either isolated rectal or bladder injury is no more controversial, their combined effect and their optimal management has been seldom reported in the English literature. From a case report of a 45-year-old male who was found to have a combined bladder and rectal injury secondary to a stab wound of the perianal area, the authors develop a diagnostic and therapeutic algorithm for the management of this uncommon trauma.
Low-Dose UVA Radiation-Induced Adaptive Response in Cultured Human Dermal Fibroblasts
Authors: Liu Zhongrong , Chen Hulin , Yang Huilan , Liang Jie , Li Xuemei
Published: July 2012

Objective.To investigate the mechanism of the adaptive response induced by low-dose ultraviolet A (UVA) radiation.Methods.Cultured dermal fibroblasts were irradiated by a lethal dose of UVA (86.4 J/cm2) with preirradiation of single or repetitive low dose of UVA (7.2 J/cm2). Alterations of cellular morphology were observed by light microscope and electron microscope. Cell cycle and cellular apoptosis were assayed by flow cytometer. The extent of DNA damage was determined by single-cell gel electrophoresis (SCGE).Results.The cultured dermal fibroblasts, with pretreatment of single or repetitive irradiation of 7.2 J/cm2UVA relieved toxic reaction of cellular morphology and arrest of cell cycle, decreased apoptosis ratio, reduced DNA chain breakage, and accelerated DNA repair caused by subsequent 86.4 J/cm2UVA irradiation. Compared with nonpretreatment groups, all those differences were significant (P<0.01orP<0.05).Conclusions.The adaptation reaction might depend on the accumulated dose of low-dose UVA irradiation. Low-dose UVA radiation might induce adaptive response that may protect cultured dermal fibroblasts from the subsequent challenged dose of UVA damage. The duration and protective capability of the adaptive reaction might be related to the accumulated dose of low-dose UVA Irradiation.
Efficacy of Proliferation of HeLa Cells under Three Different Low-Intensity Red Lasers Irradiation
Authors: Yang H. Q. , Wang Y. H. , Chen J. X. , Chen X. G. , Huang Y. M. , Li H. , Xie S. S. , Zheng L. Q.
Published: July 2012

This study was intended to compare the efficacy of proliferation of HeLa cells under three different low-intensity laser irradiation (LIL), that is, 633 nm, 658 nm, and 785 nm. The time-dependent responses of proliferation of HeLa cells after the red laser irradiation and the influence of fetal bovine serum (FBS) at 1%, 2%, 5%, or 10% on the proliferation of cells were also investigated. The results indicated that the proliferation of HeLa cells in 10% FBS was in proliferation-specific homeostasis (PSH) so that it was not modulated with LIL; the proliferation in FBS at 1%, 2%, or 5% was far from PSH so that it may be wavelength dependently modulated with LIL, and the maximum proliferation promotion was conducted with LIL at 633 nm amongst the three different LIL. It was concluded the wavelength-dependent photobiomodulation of LIL on proliferation of HeLa cells may be homeostatic.
EFD and CFD Characterization of a CLT Propeller
Authors: Bertetta Daniele , Brizzolara Stefano , Canepa Edward , Gaggero Stefano , Viviani Michele
Published: July 2012

In the present paper an experimental and numerical analysis of an unconventional CLT propeller is carried out. Two different numerical approaches, a potential panel method and an RANSE solver, are employed. Cavitation tunnel experiments are carried out in order to measure, as usual, thrust, torque, and cavity extension for different propeller working points. Moreover, LDV measurements are performed to have a deep insight into the complex wake behind the propeller and to analyze the dynamics of generated tip vortexes. The numerical/experimental analysis and comparison of results highlight the peculiarities of this kind of propellers, the possibility to increase efficiency and reduce cavitation risk, in order to exploit the design approaches already well proven for conventional propellers also in the case of these unconventional geometries.
Blocked Atrial Bi/Trigeminy In Utero Evolving in Supraventricular Tachycardia after Birth
Authors: Martucci V. , Cerekja A. , Caiaro A. , Bosco G. , Lucchini R. , Piacentini G. , Marino B. , Ventriglia Flavia
Published: July 2012

Transient episodes of fetal bradycardia (heart rate less than 110 bpm) are usually benign and typically result from increased vagal stimulation in the fetus. Causes of sustained fetal bradycardia include sinus bradycardia, blocked atrial bigeminy/trigeminy, high-degree atrioventricular block, and long QT syndrome. We present the case of a 34-year-old Caucasian patient referred to our department for “blocked atrial bigeminy with pseudobradycardia” detected elsewhere at 33 weeks of gestation. A fetal echocardiography showed during all the examination a blocked atrial trigeminy with a mean fetal heart rate of 100 bpm. After birth three subsequent ECGs until day 3 showed no evidence of atrial extrasystoles, confirming the well-known frequent regression of this kind of fetal benign arrhythmia, but on day 11 recurrence of supraventricular trigeminy and development of episodes of paroxystic supraventricular tachycardia were observed. On the basis of this observation, we recommend that fetuses with complex atrial ectopic beats should be closely monitored before and after birth for evidence of new arrhythmias.
The Use of Amberlite Adsorbents for Green Chromatography Determination of Volatile Organic Compounds in Air
Authors: Juan-Peiró Luis , Bernhammer Anne , Pastor Agustin , de la Guardia Miguel
Published: July 2012

Passive samplers have been widely used for volatile organic compounds determination. Following the green chemistry tendency of the direct determination of adsorbed compounds in membrane-based devices through using head space direct chromatography analysis, this work has evaluated the use of Amberlite XAD-2, XAD-4, and XAD-16 adsorbents as a filling material for passive samplers. Direct analysis of the membranes by HS-GC-MS involves a solvent-free method avoiding any sample treatment. For exposed membranes, recoveries ranged from 10% to 203%, depending on the compound and adsorbent used. The limit of the detection values ranged from 1 to 140 ng per sampler. Acceptable precision and sensitivity levels were obtained for the XAD resins assayed.
How Similar Are Inbred Rats? The Influence of Anatomical Variations, Shipment and Sampling Time on Experimental Surgery
Authors: Jin H. , Huang H. , Zhang J. , Dirsch O. , Dahmen U.
Published: July 2012

Variations among inbred rats in terms of anatomy and routine laboratory values can potentially blur surgical experimental results. Therefore, a retrospective analysis aiming at investigating hepatic and perihepatic anatomical variations, liver weight, body weight, liver weight/body weight ratio (LBWR), variations in routine laboratory values, and the influence of shipment and repeated sampling was performed. In our study, liver weight of rats seemed to be strain-specific. LBWR was weakly and negatively correlated with body weight in rats. A statistically significant difference in routine blood tests was found among normal rats grouped by different body weight or shipment. Weekly repeated sampling from the same rats revealed a statistically significant difference in a blood test. In conclusion, the fact that variation among rats or their environment can blur the results of a surgical experimental study should be kept in mind.
Motor Symptoms and Schizophrenia
Authors: Walther Sebastian , Strik Werner
Published: July 2012

Classical schizophrenia literature reports motor symptoms as characteristic of the disorder. After the introduction of neuroleptic drugs, the existence of genuine motor disorders was challenged. Renewed interest arose as symptoms were found in never-medicated patients. Reports focused on abnormal involuntary movements, parkinsonism, neurological soft signs, catatonia, negative symptoms, or psychomotor slowing. Since these syndromes refer to different concepts, however, the definitions are not congruent and the symptoms overlap. The prevalence rates of motor symptoms in schizophrenia are surprisingly high, and recent studies indicate a possible pathobiology. In particular, the development and maturation of the human motor system appears to be closely linked to the emergence of motor symptoms observed in schizophrenia. Post-mortem and neuroimaging results demonstrated aberrant structure and function of premotor and motor cortices, basal ganglia, thalamus, and the connecting white matter tracts. Animal models have focused on aberrant neurotransmission and genetic contributions. Findings of localized abnormal oligodendrocyte function and myelination point to the special role of the white matter in schizophrenia, and recent studies specifically found an association between motor abnormalities and white matter structure in schizophrenia. This review of the literature supports the idea that motor symptoms are closely related to the neurodevelopmental disturbances of schizophrenia and a distinct syndromal dimension with its own pathophysiology.
History of Frequent Gum Chewing Is Associated with Higher Unstimulated Salivary Flow Rate and Lower Caries Severity in Healthy Chinese Adults
Authors: Wang X.P. , Zhong B. , Chen Z.K. , Stewart M.E. , Zhang C. , Zhang K. , Ni J. , Dodds M.W.J. , Hanley A.B. , Miller L.E.
Published: July 2012

This was a single-center, prospective, cross-sectional study stratified by age and gender with the objective of determining the relationship between gum chewing history, salivary flow, and dental caries severity in adults. We enrolled 191 subjects aged 18–65 years who underwent assessments for gum chewing history, unstimulated salivary flow rate, salivary pH, and caries severity. Unstimulated salivary flow rate tended to decline with increasing age (p = 0.04), and significant differences in unstimulated salivary flow rate were also found for males (0.58 ± 0.32 ml/min) versus females (0.48 ± 0.30 ml/min) (p = 0.02). Weekly gum chewing frequency was greater in younger subjects (p = 0.001) while no age group differences were noted in pieces per day or chewing duration. Gum chewing habits were similar in males and females. A multivariate model demonstrated that only days per week chewing gum (p < 0.001) and gender (p = 0.007) were predictive of unstimulated salivary flow rate (R2 = 0.40). Mean caries severity scores, assessed via ICDAS II and DMFT, increased with age. In multivariate analysis, age was positively associated with ICDAS (p = 0.001) and days per week chewing gum was negatively associated with ICDAS (p = 0.004), indicating that caries severity increased with age, and that days of chewing provided an inverse effect, with increased days of chewing being associated with decreased severity of caries. Overall, a history of frequent gum chewing is associated with higher unstimulated salivary flow rate and lower caries severity.
Combined Values of Serum Albumin, C-Reactive Protein and Body Mass Index at Dialysis Initiation Accurately Predicts Long-Term Mortality
Authors: Takahashi Ryo , Ito Yasuhiko , Takahashi Hiroshi , Ishii Hideki , Kasuga Hirotake , Mizuno Masashi , Suzuki Yasuhiro , Yuzawa Yukio , Maruyama Shoichi , Murohara Toyoaki , Imai Enyu , Matsuo Seiichi
Published: July 2012

Background: Protein-energy wasting and chronic inflammation are prevalent in patients with end-stage renal disease (ESRD). We investigated the combination of serum albumin, C-reactive protein (CRP) and body mass index (BMI) at initiation of hemodialysis therapy as a predictor of all-cause and cardiovascular disease (CVD) mortality in Japanese ESRD patients. Methods: A total of 1,228 consecutive Japanese ESRD patients on hemodialysis therapy were enrolled and followed for up to 10 years. Patients were divided into quartiles according to levels of albumin, CRP and BMI. Furthermore, to clarify the joint role of these factors, albumin <3.5 g/dl, CRP >4.0 mg/l and BMI <19.6 were defined as risk factors using receiver operating characteristic analysis; thereafter, patients were divided into groups according to the positive number of these factors. Results: Adjusted hazard ratios (HRs) for lower serum albumin, elevated CRP and lower BMI for 10-year all-cause mortality were 1.97, 3.13 and 2.61, respectively. Regarding the combination of these variables, adjusted HRs for mortality were 2.31, 4.28 and 8.07, respectively, in patients having any one factor, any two factors and all three factors. The C-index for an established risk model with these three positive markers was the most accurate for predicting mortality (0.768), as compared to other models with one or two markers. Similar results were seen for CVD mortality. Conclusions: Serum albumin, CRP and BMI at the start of hemodialysis therapy were able to individually stratify the risk of long-term mortality in ESRD patients. Furthermore, a combination of these variables could more accurately predict mortality.
Management of Left Ventricular Rupture After Myocardial Infarction Solely With ECMO
Authors: Abedi-Valugerdi Golbarg , Gabrielsen Anders , Fux Thomas , Hillebrant Carl-Gustaf , Lund Lars H. , Corbascio Matthias
Published: July 2012

Supplemental Digital Content is available in the text.
Circulation: Heart Failure
Editors’ Picks
Authors: Kociol Robb D.
Published: July 2012

The following are highlights from
Circulation: Heart Failure
Topic Review. This series summarizes the most important articles, as selected by the editors, that have been published in the
Circulation
portfolio. The objective of this series is to provide our readership with a timely comprehensive selection of important articles that are relevant to the heart failure audience. The studies included in this article represent the most noteworthy research in the areas of heart failure and therapeutics.
Role of Protease-Activated Receptor-1 in Brain Injury After Experimental Global Cerebral Ischemia
Authors: Wang Jinhu , Jin Hang , Hua Ya , Keep Richard F. , Xi Guohua
Published: July 2012

Background and Purpose—

Evidence suggests that the protease-activated receptor-1 (PAR-1), a thrombin receptor, mediates neuronal injury in experimental cerebral ischemia. The present study investigated whether PAR-1 plays a role in brain injury after global cerebral ischemia.

Methods—

Adult male wild-type or PAR-1 knockout mice underwent a 20-minute bilateral common carotid artery occlusion or a sham operation. Behavior tests were performed before ischemia and 1, 2, and 3 days after bilateral common carotid artery occlusion. Mice were euthanized at different time points for thrombin activity, brain edema, Western blot analysis, and brain histology.

Results—

Thrombin activity and PAR-1 expression were increased in the brain after bilateral common carotid artery occlusion. Compared with wild-type mice, PAR-1 knockout mice had less brain edema formation, neuronal death, and behavior impairment after bilateral common carotid artery occlusion. In addition, bilateral common carotid artery occlusion-induced activation of mitogen-activated protein kinases was absent in PAR-1 knockout mice.

Conclusion—

PAR-1 contributes to the brain injury induced by global cerebral ischemia, which may be related to activation of mitogen-activated protein kinases.
Electricity Unit Value Prices and Purchase Quantities: U.S. Manufacturing Plants, 1963–2000
Authors: Davis Steven J. , Grim Cheryl , Haltiwanger John , Streitwieser Mary
Published: July 2012

We measure unit value electricity prices using 2 million annual observations on U.S. manufacturing plants from 1963 to 2000. These prices display tremendous cross-sectional dispersion, 85–95% of which reflects differences by plant location and purchase quantity. Spatial differentials decline markedly until the late 1980s for large purchasers but rise over time for small purchasers. Unit value price gaps between larger and smaller purchasers are enormous, diminish through the late 1970s, and then stabilize at still-high levels. There are major differences across states in cost and regulatory factors that we relate to the changing structure of unit value prices.