bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient Heat Transfer in a Partially Cooled Cylindrical Rod
Authors: Agbezuge Lawrence
Published: May 2009

Finite element and finite difference solutions are obtained for transient temperature distribution in a partially cooled cylindrical rod that generates heat at a uniform rate. A portion of the rod is immersed in a coolant reservoir that is maintained at constant temperature, and the exposed portion of the rod is cooled by convective heat transfer. Because thermal conductivity of the rod is temperature dependent, the governing partial differential equation is nonlinear. The analytical techniques utilized in solving the problem could be applied to analyzing the cooling of spent nuclear fuel rods. The finite difference method used to solve the problem utilizes an implicit formulation of the governing equation, and a numerical technique for handling the nonlinear terms. Validation of the numerical solution is obtained by comparing the results at a specified time against those generated by a commercial finite element software package. The computer model for the problem was used to estimate heat generation rates that could initiate meltdown of a fuel rod.
Novel Hub Fins for Axial Flow Fans for the Enhancement of Impingement Heat Transfer on a Flat Plate
Authors: Sui D. , Kim T. , Xu M. L. , Lu T. J.
Published: May 2009

The thermal characteristics of exit flow issued from an axial fan widely used for impingement cooling of power electronics are experimentally studied. A new fan configuration is proposed to improve the impingement cooling performance at the center of a uniformly heated flat plate. Results demonstrate that the addition of fin attachments to the fan hub housing the driving motor intensifies reverse flow from the plate, leading to enhanced local heat transfer (up to 12%) relative to that of a reference fan. The effectiveness of hub fin attachments is limited to relatively short impinging distances (H/D<0.6).
An Experimental Study on the Design of Miniature Heat Sinks for Forced Convection Air Cooling
Authors: Egan Vanessa , Stafford Jason , Walsh Pat , Walsh Ed
Published: May 2009

An experimental study is performed on one of the smallest commercially available miniature fans, suitable for cooling portable electronic devices, used in conjunction with both finned and finless heat sinks of equal exterior dimensions. The maximum overall footprint area of the cooling solution is 534mm2 with a profile height of 5 mm. Previous analysis has shown that due to fan exit angle, flow does not enter the heat sinks parallel to the fins or bounding walls. This results in a nonuniform flow rate within the channels of the finned and finless heat sinks along with impingement of the flow at the entrance giving rise to large entrance pressure losses. In this paper straightening diffusers were attached at the exit of the fan, which resulted in aligning the flow entering the heat sinks with the fins and channel walls. Detailed velocity measurements were obtained using particle image velocimetry, which provided a further insight into the physics of the flow in such miniature geometries and in designing the straightening diffusers. The thermal analysis results indicate that the cooling power of the solution is increased by up to 20% through the introduction of a diffuser, hence demonstrating the need for integrated fan and heat sink design of low profile applications.
Systematic Approaches for Design of Distribution Manifolds Having the Same Per-Port Outflow
Authors: Chen Andrew W. , Sparrow Ephraim M.
Published: May 2009

Two geometric modalities were investigated to determine their effects on the degree of uniformity of the flow issuing from a manifold through a discrete set of exit ports. The goal of the investigation was to demonstrate how these geometric parameters can be used to achieve a high degree of exit-flow uniformity. The first investigated modality is the area ratio, which compares the total outflow area of all the exit ports with the cross-sectional area of the manifold. The second modality is the extent of pressure loading downstream of the exit ports of the manifold. The investigation was facilitated by numerical simulation for which an appropriate turbulence model was used. Three parameters were varied during the course of the research: (a) the area ratio, (b) the downstream pressure loading characterized by the length-to-diameter ratio of the outflow tubes that are attached to the exit ports, and (c) the Reynolds number. It was found that the area ratio parameter had a marked effect on the uniformity of the outflow from the manifold. Quantitative values of the area ratio corresponding to specified degrees of uniformity (i.e., 2%, 5%, and 10%) were identified. This information can be used as a guideline for manifold design. The imposition of the downstream pressure loading was also demonstrated to have a significant effect on the degree of uniformity, but that effect was not as strong as the effect of the area ratio. The manifold pressure was found to increase from the inlet of the manifold to the downstream end of the manifold. The direction of the jetlike discharge from the exit ports of the manifold into a large collection domain was found to vary along the length of the manifold, with inclined jets emanating from the upstream end and perpendicular jets at the downstream end. Over the range of investigated Reynolds numbers, from 40,000 to 200,000, the degree of uniformity of the mass effusion from the exit ports was found to be unaffected. The results of the numerical simulations were confirmed by experiments.
Particle Image Velocimetry Study of Rough-Wall Turbulent Flows in Favorable Pressure Gradient
Authors: Tay G. F. K. , Kuhn D. C. S. , Tachie M. F.
Published: May 2009

This paper reports an experimental investigation of the effects of wall roughness and favorable pressure gradient on low Reynolds number turbulent flow in a two-dimensional asymmetric converging channel. Flow convergence was produced by means of ramps (of angles 2 deg and 3 deg) installed on the bottom wall of a plane channel. The experiments were conducted over a smooth surface and over transitionally rough and fully rough surfaces produced from sand grains and gravel of nominal mean diameters 1.55 mm and 4.22 mm, respectively. The dimensionless acceleration parameter was varied from 0.38×10−6 to 3.93×10−6 while the Reynolds number based on the boundary layer momentum thickness was varied from 290 to 2250. The velocity measurements were made using a particle image velocimetry technique. From these measurements, the distributions of the mean velocity and Reynolds stresses were obtained to document the salient features of transitionally and fully rough low Reynolds number turbulent boundary layers subjected to favorable pressure gradient.
One-Dimensional Unsteady Periodic Flow Model with Boundary Conditions Constrained by Differential Equations
Authors: Nguyen Nhan T.
Published: May 2009

This paper describes a modeling method for closed-loop unsteady fluid transport systems based on 1D unsteady Euler equations with nonlinear forced periodic boundary conditions. A significant feature of this model is the incorporation of dynamic constraints on the variables that control the transport process at the system boundaries as they often exist in many transport systems. These constraints result in a coupling of the Euler equations with a system of ordinary differential equations that model the dynamics of auxiliary processes connected to the transport system. Another important feature of the transport model is the use of a quasilinear form instead of the flux-conserved form. This form lends itself to modeling with measurable conserved fluid transport variables and represents an intermediate model between the primitive variable approach and the conserved variable approach. A wave-splitting finite-difference upwind method is presented as a numerical solution of the model. An iterative procedure is implemented to solve the nonlinear forced periodic boundary conditions prior to the time-marching procedure for the upwind method. A shock fitting method to handle transonic flow for the quasilinear form of the Euler equations is presented. A closed-loop wind tunnel is used for demonstration of the accuracy of this modeling method.
Exit Flow Behavior of Axial Fan Flows With/Without Impingement
Authors: Sui D. , Wang S. S. , Mao J. R. , Kim T. , Lu T. J.
Published: May 2009

The exit flow patterns of an axial flow fan widely used in electronics cooling are experimentally characterized both in free exit and in the presence of a flat impingement plate. The axial fan is rotated with 12.0 V input from a dc power supply, leading to a nominal Reynolds number of Re=9.0×103 based on fan diameter. One shear layer each is found to form between the exit flow from the axial fan and the surrounding fluid at rest, and between the exit flow and the flow along the fan axis. In addition to creating a highest wall pressure region (the primary stagnation region), the presence of the flat plate induces a flow recirculation zone (the secondary stagnation region) at the plate center. When the fan exit-to-plate spacing normalized by fan diameter (H/D) equals to about 0.6, the wall pressure is minimized in the secondary stagnation region due to the maximized “recirculation” as a result of intensified flow interaction. Within the range considered (0.2≤H/D≤2.0) and with the case of H/D∼0.6 serving as a reference, the flow interaction tends to be suppressed by the proximity of the plate at H/D=0.2 and weakened due to the momentum dissipation at H/D∼2.0.
INFLATION FROM IIB SUPERSTRINGS WITH FLUXES
Authors: RAMÍREZ ERANDY , MATOS TONATIUH , QUIROS ISRAEL
Published: May 2009

We study the conditions needed to have an early epoch of inflationary expansion with a potential coming from type IIB superstring theory with fluxes involving two modulus fields. The phenomenology of this potential is different from the usual hybrid inflation scenario and we analyze the possibility that the system of field equations undergoes a period of inflation in three different regimes with the dynamics modified by a Randall–Sundrum term in the Friedmann equation. We find that the system can produce inflation and, due to the modification of the dynamics, a period of accelerated contraction can follow or precede this inflationary stage, depending on the sign of one of the parameters of the potential. We discuss the viability of this model in a cosmological context.
THE COMBINED ANALYSIS OF πN → TWO MESONS + N REACTIONS WITHIN REGGEON EXCHANGES AND DATA FOR $p\bar p$ (AT REST) → THREE MESONS
Authors: ANISOVICH V. V. , SARANTSEV A. V.
Published: May 2009

The novel point of this analysis is a direct use of the Reggeon exchange technique for the description of the reactions πN → two mesons + N at large energies of the initial pion. This approach allows us to describe simultaneously distributions over M (invariant mass of two mesons) and t (momentum transfer squared to nucleons). Making use of this technique, the following resonances (as well as corresponding bare states), produced in the πN→π0π0N reaction, are studied: f0(980), f0(1300) [f0(1370) in PDG notation], f0(1200–1600), f0(1500), f0(1750), f2(1270), f2(1525), f2(1565), f2(2020), f4(2025). Adding data for the reactions [Formula: see text] (at rest, from liquid H2) →π0π0π0, π0π0η, π0ηη and [Formula: see text] (at rest, from gaseous H2) →π0π0π0, π0π0η, π0ηη, we have performed a simultaneous K matrix fit of two-meson spectra in all these reactions. The results of combined fits to the above-listed isoscalar fJ states and to isovector ones, a0(980), a0(1475), a2(1320), are presented.
NJL INTERACTION DERIVED FROM QCD: VECTOR AND AXIAL-VECTOR MESONS
Authors: ARBUZOV B. A. , VOLKOV M. K. , ZAITSEV I. V.
Published: May 2009

In previous works effective nonlocal SU (2)× SU (2) NJL model was proposed in which all the parameters are expressed through those of the fundamental QCD: current light quark mass m0 and average nonperturbative αs. The results for scalar and pseudoscalar mesons are in satisfactory correspondence to existing data. In the present work the same model without introduction of any additional parameters is applied for a description of masses and strong decay widths of ρ- and a1-mesons. The results for both scalar and vector sectors agree with data up to accuracy of the model.
ENHANCEMENT OF SPIKE SYNCHRONY IN HINDMARSH–ROSE NEURAL NETWORKS BY RANDOMLY REWIRING CONNECTIONS
Authors: YANG RENHUAN , SONG AIGUO , YUAN WUJIE
Published: May 2009

Spike synchrony of the neural system is thought to have very dichotomous roles. On the one hand, it is ubiquitously present in the healthy brain and is thought to underlie feature binding during information processing. On the other hand, large scale synchronization is an underlying mechanism of epileptic seizures. In this paper, we investigate the spike synchrony of Hindmarsh–Rose (HR) neural networks. Our focus is the influence of the network connections on the spike synchrony of the neural networks. The simulations show that desynchronization in the nearest-neighbor coupled network evolves into accurate synchronization with connection-rewiring probability p increasing. We uncover a phenomenon of enhancement of spike synchrony by randomly rewiring connections. With connection strength c and average connection number m increasing spike synchrony is enhanced but it is not the whole story. Furthermore, the possible mechanism behind such synchronization is also addressed.
ON IMPROVING BIPEDAL WALKING ENERGETICS THROUGH ADJUSTING THE STIFFNESS OF ELASTIC ELEMENTS AT THE ANKLE JOINT
Authors: GHORBANI REZA , WU QIONG
Published: May 2009

Impact at each leg transition is one of the main causes of energy dissipation in most of the current bipedal walking robots. Minimizing impact can reduce the energy loss. Instead of controlling the joint angle profiles to reduce the impact, which requires a significant amount of energy, installing elastic mechanisms (with adjustable stiffness) on the robots structure is proposed in this paper, enabling the robot to reduce the impact, and to store part of the energy in the elastic form and return it to the robot. The conceptual design of an adjustable stiffness artificial tendon is proposed which is added to the ankle joint of a bipedal walking robot model. Simulation results on the stance phase demonstrate significant improvements in the energetics of the bipedal walking robot by proper stiffness adjustment of the tendon as compared to using a single linear spring. A controller based on energy feedback is designed to automatically adjust the stiffness of the tendon. Computer simulations illustrate improvements in performance of the energetics of the bipedal walking robot in consecutive walking steps while the stiffness of the tendon is adjusted properly.
PUBLIC ATTITUDES AND PARTICIPATION IN WIND TURBINE DEVELOPMENT
Authors: COLEBY ALASTOR M. , MILLER DAVID R. , ASPINALL PETER A.
Published: May 2009

Research for this paper was undertaken into the relationship between public opinion on wind power and public participation in turbine site planning and design. The research focussed on the contribution of environmental attitude studies to participatory environmental impact assessment of renewable energy policy and land use. A questionnaire survey was undertaken at wind farm sites at three stages in the site planning process and at three public events where the application of wind power was a topic of discussion. The attitudinal data produced was subjected to a series of statistical tests to determine which of the attitudes revealed could be quantified significantly in terms of public opinion. The most significant responses related to the proximity of wind turbines to respondents' homes with the proposition that wind turbine designers should seek community input of the highest significance. Respondents also indicated a preference for traditional turbine structures that blended in with the landscape and remained out of sight. Respondents' personal perception of land use change regarding wind power near them was mostly significant relative to respondent age with younger respondents tending to be more accepting of wind turbine land use whilst older respondents objected. Living place was also found to be significant with urban respondents more accepting of wind power than rural ones. Fundamentally respondents although polarised for or against on certain issues, all shared a wish for more public input and participation in local land use for wind power.
Active SAR Antennas: Design, Development, and Current Programs
Authors: Capece P.
Published: May 2009

The paper presents the design guidelines for Active SAR Antennas followed for the development of COSMO Sky Med SAR Antenna Subsystem. They have brought to define the antenna architecture, the RF, and electrical requirements for all the antenna RF, digital and power units, taking into account the available technologies and achievable performance. The antenna design is described for what the main subsystems is concerned, such as RF, power, digital, including mechanical and thermal aspects. Finally the paper reports also a brief description of the most recent development carried out in Canada and in Europe in the last ten years, including the on-going programs.
Nicotinic Acid‐Mediated Activation of Both Membrane and Nuclear Receptors towards Therapeutic Glucocorticoid Mimetics for Treating Multiple Sclerosis
Authors: Penberthy W. Todd
Published: May 2009

Acute attacks of multiple sclerosis (MS) are most commonly treated with glucocorticoids, which can provide life‐saving albeit only temporary symptomatic relief. The mechanism of action (MOA) is now known to involve induction of indoleamine 2,3‐dioxygenase (IDO) and interleukin‐10 (IL‐10), where IL‐10 requires subsequent heme oxygenase‐1 (HMOX‐1) induction. Ectopic expression studies reveal that even small changes in expression of IDO, HMOX‐1, or mitochondrial superoxide dismutase (SOD2) can prevent demyelination in experimental autoimmune encephalomyelitis (EAE) animal models of MS. An alternative to glucocorticoids is needed for a long‐term treatment of MS. A distinctly short list of endogenous activators of both membrane G‐protein‐coupled receptors and nuclear peroxisome proliferating antigen receptors (PPARs) demonstrably ameliorate EAE pathogenesis by MOAs resembling that of glucocorticoids. These dual activators and potential MS therapeutics include endocannabinoids and the prostaglandin 15‐deoxy‐Δ12,14‐PGJ2. Nicotinamide profoundly ameliorates and prevents autoimmune‐mediated demyelination in EAE via maintaining levels of nicotinamide adenine dinucleotide (NAD), without activating PPAR nor any G‐protein‐coupled receptor. By comparison, nicotinic acid provides even greater levels of NAD than nicotinamide in many tissues, while additionally activating the PPARγ‐dependent pathway already shown to provide relief in animal models of MS after activation of GPR109a/HM74a. Thus nicotinic acid is uniquely suited for providing therapeutic relief in MS. However nicotinic acid is unexamined in MS research. Nicotinic acid penetrates the blood brain barrier, cures pellagric dementia, has been used for over 50 years clinically without toxicity, and raises HDL concentrations to a greater degree than any pharmaceutical, thus providing unparalleled benefits against lipodystrophy. Summary analysis reveals that the expected therapeutic benefits of high‐dose nicotinic acid administration far outweigh any known adverse risks in consideration for the treatment of multiple sclerosis.
Combined Src and Aromatase Inhibition Impairs Human Breast Cancer GrowthIn vivoand Bypass Pathways Are Activated in AZD0530-Resistant Tumors
Authors: Chen Yi , Guggisberg Natalia , Jorda Merce , Gonzalez-Angulo Ana , Hennessy Bryan , Mills Gordon B. , Tan Chen-Keat , Slingerland Joyce M.
Published: May 2009

Purpose: Antiestrogens are used to treat estrogen receptor (ER)-α-positive breast cancers and cause a p27-dependent G1 arrest. Estrogen-bound ER recruits Src to mediate proteolysis of p27 and drive cell proliferation. Here, we tested the antitumor efficacy of combined Src and aromatase inhibition for ER-positive breast cancer.

Experimental Design: Antiproliferative effects of the aromatase inhibitor, anastrozole, and Src inhibitor, AZD0530, alone or in combination were tested in vitro and in vivo on aromatase-transfected MCF-7Arom5 xenografts. Xenografts were analyzed by immunohistochemistry and proteomic analysis to identify potential biomarkers of drug response and resistance.

Results: AZD0530 and anastrozole together increased p27 and caused greater G1 cell cycle arrest than either drug alone. AZD0530 monotherapy initially retarded xenograft growth in vivo, but drug resistance rapidly emerged. Combined anastrozole/AZD0530 reduced drug resistance and showed greater antitumor efficacy in vivo with greater Src and epidermal growth factor receptor inhibition and a greater increase in p27 and reduction of Ki-67 than either drug alone, supporting further evaluation of these putative predictors of response to combined Src/aromatase inhibition in vivo. Anastrozole alone stimulated Src activity both in vitro and in vivo. AZD0530-resistant tumors showed activation of bypass pathways including MEK and phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin, raising the possibility that MEK, mammalian target of rapamycin (mTOR), or PI3K inhibitors may augment Src inhibitor efficacy.

Conclusions: These data support clinical investigation of anastrozole-AZD0530 therapy for postmenopausal ER-positive breast cancer. Loss of p27 and increased Ki-67 may predict response and further clinical studies should evaluate for activation of bypass pathways including MEK and PI3K pathways during Src inhibitor therapy.
A complex medical phenotype in a patient with triplication of 2q12.3 to 2q13 characterized with oligonucleotide array CGH
Authors: Mercer C.L. , Browne C.E. , Barber J.C.K. , Maloney V.K. , Huang S. , Thomas N.S. , Foulds N.
Published: May 2009

We report an adult female with a left polycystic kidney, patent ductus arteriosus, left streak ovary, bicornuate uterus and deafness who presented with infertility. She has an intrachromosomal triplication of bands 2q12.3 to 2q13, with inversion of the central segment, which arose de novo from a paternal interchomosomal event. The triplication contains 68 known genes within the 7.28 Mb of DNA between base pairs 107,140,721 and 114,416,131. All intrachromosomal triplications are rare and, while partial duplications of 2q have been previously described, this patient is a unique surviving case of a triplication of proximal 2q.
Serum Albumin in Ischemic Stroke Patients: The Higher the Better
Authors: Idicula Titto T. , Waje-Andreassen Ulrike , Brogger Jan , Naess Halvor , Thomassen Lars
Published: May 2009

Background: Animal studies show a neuroprotective effect of serum albumin in ischemic stroke. The neuroprotective effect of albumin in ischemic stroke in humans is not well studied. This study was aimed to determine the association of serum albumin with outcome and mortality after ischemic stroke. Methods: In a prospective study, we included 444 patients with ischemic stroke. Serum albumin was measured at the time of admission. Stroke severity was measured at the time of admission with the National Institutes of Health Stroke Scale (NIHSS). Functional outcome was measured with the modified Rankin scale (mRS) on day 7. Multiple logistic regression analysis was used to assess the independent association between variables and outcome. Survival was analyzed by Cox regression analysis after adjusting for age, sex and NIHSS score on admission. Results: The mean age (SD) of the patients was 70.4 (14.4) years. The median NIHSS score (interquartile range) on admission was 4 (1–8) and the median mRS score (interquartile range) on day 7 was 2 (1–3). Sixty patients (13%) died during a median follow-up period of 2 years. High serum albumin was independently associated with a better outcome (OR = 1.12, 95% CI = 1.05–1.20, p = 0.001). After adjusting for age, sex and NIHSS score on admission, high serum albumin was associated with lower mortality (OR = 0.88, 95% CI = 0.83–0.93, p < 0.0001). Conclusions: The current study indicates that high serum albumin is associated with better outcome and lower mortality in ischemic stroke patients. High serum albumin may be neuroprotective in ischemic stroke in humans.
Early Hospital Arrival Improves Outcome at Discharge in Ischemic but Not Hemorrhagic Stroke: A Prospective Multicenter Study
Authors: Naganuma Masaki , Toyoda Kazunori , Nonogi Hiroshi , Yokota Chiaki , Koga Masatoshi , Yokoyama Hiroyuki , Okayama Akira , Naritomi Hiroaki , Minematsu Kazuo
Published: May 2009

Background: Our purpose was to determine whether the onset-to-arrival time affects the outcome of stroke patients. Methods: We carried out a prospective multicenter study involving 1,817 patients with ischemic stroke and 1,226 with intracerebral hemorrhage who presented to hospitals within 24 h of symptom onset. The primary outcome was independent activity of daily living corresponding to a modified Rankin Scale (mRS) score ≤2 at discharge approximately 3 weeks after stroke. Results: In ischemic stroke patients, the initial NIH Stroke Scale (NIHSS) score decreased as the onset-to-arrival time increased: 9 (median) in the earliest tertile group (<3 h), 5 in the second tertile group (3–8 h) and 4 in the latest tertile group (≥8 h, p < 0.001). The median mRS scores at discharge in these groups were 3, 2 and 2, respectively (p < 0.001). After adjustment for underlying features and the initial NIHSS score, the independent activity of daily living at discharge was 1.73 times more common in patients in the earliest group than in the latest group (95% CI = 1.24–2.42, p = 0.001). A similar tendency was shown in the subanalysis for large-artery atherosclerosis and cardioembolic stroke. In intracerebral hemorrhage patients, both the initial NIHSS score and the mRS score at discharge decreased as the onset-to-arrival time increased. After multivariate adjustment, the independent activity of daily living was 2.33 times (p < 0.001) and 1.69 times (p = 0.006) less common in patients in the earliest (<1.2 h) and second tertile groups (1.2–3.5 h), respectively, than in the latest tertile group (≥3.5 h). Conclusions: Early hospital arrival improved the clinical outcome in ischemic stroke patients but not in patients with intracerebral hemorrhage.
Development of a Chimeric DNA-RNA Hammerhead Ribozyme Targeting SARS Virus
Authors: Fukushima Akiko , Fukuda Noboru , Lai Yimu , Ueno Takahiro , Moriyama Mitsuhiko , Taguchi Fumihiro , Iguchi Akifumi , Shimizu Kazushi , Kuroda Kazumichi
Published: May 2009

Objective: Severe acute respiratory syndrome (SARS) is a severe pulmonary infectious disease caused by a novel coronavirus. To develop an effective and specific medicine targeting the SARS-coronavirus (CoV), a chimeric DNA-RNA hammerhead ribozyme was designed and synthesized using a sequence homologous with the mouse hepatitis virus (MHV). Method: Chimeric DNA-RNA hammerhead ribozyme targeting MHV and SARS-CoV were designed and synthesized.To confirm its activity, in vitro cleavage reactions were performed with the synthesized ribozyme. Effects of the chimeric ribozyme were evaluated on multiplication of MHV. Effects of the chimeric ribozyme on expression of SARS-CoV were evaluated in cultured 3T3 cells. Result: The synthetic ribozyme cleaved the synthetic target MHV and SARS-CoV RNA into fragments of predicted length. The chimeric DNA-RNA hammerhead ribozyme targeting SARS-CoV significantly inhibited multiplication of MHV in DBT cells by about 60%. The chimeric DNA-RNA hammerhead ribozyme targeting SARS-CoV significantly inhibited the expression of SARS-CoV RNA in 3T3 cells transfected with the recombinant plasmid. The chimeric DNA-RNA ribozyme targeting SARS-CoV significantly inhibited MHV viral activity and expression of recombinant SARS RNA in vitro. Conclusion: These findings indicate that the synthetic chimeric DNA-RNA ribozyme could provide a feasible treatment for SARS.
A Novel Food Processing Technique by a Wild Mountain Gorilla (Gorilla beringei beringei)
Authors: Sawyer Sarah C. , Robbins Martha M.
Published: May 2009

Innovation, the invention of new behavior, has been observed in wild primates only infrequently. The processing of thistle (Cardus nyassanus) has previously been described as being one of the most complex food processing techniques used by mountain gorillas (Gorilla beringei beringei). We report a case of innovation in thistle leaf processing by a subadult female mountain gorilla in Bwindi Impenetrable National Park, Uganda. This technique involved rolling the thistle leaves into a ball between her palms prior to putting them in her mouth, as opposed to the standard method of folding leaves. All other weaned individuals (n = 13) were observed to use the standard method to process thistle leaves as described in Byrne et al. While the subadult female emigrated out of the research group 6 months after she had first been observed using the innovative technique, preventing observations of possible transmission within the group, it adds to the debate of whether food processing techniques used by gorillas are socially learned or not.
Radial Optic Neurotomy for Central Retinal Vein Occlusion: Long-Term Retinal Perfusion Outcome
Authors: Callizo Josep , Kroll Peter , Mennel Stefan , Schmidt Joerg C. , Meyer Carsten H.
Published: May 2009

Background/Aims:To analyze the long-term changes in retinal perfusion and functional improvement induced by radial optic neurotomy (RON) in central retinal vein occlusion (CRVO). Methods: Sixty-three eyes of 63 consecutive patients with CRVO were included. Twenty-eight (44.5%) patients underwent RON and 35 (55.5%) were followed as a control group. Time of arteriovenous transit and visual acuity were determined at baseline and after 1-year follow-up. Results:After 1 year, retinal perfusion status improved in 63.1% of operated eyes and 14.3% of controls (p = 0.048). The improvement in arteriovenous retinal transit was statistically significant (p = 0.023) only in the RON group. The visual improvement in the RON group was significantly better (p = 0.043) than in the control group. Moreover, the development of chorioretinal anastomosis was significantly higher (p = 0.036) after RON than in controls and correlated with better functional results. In operated eyes there was a lower incidence of CRVO-related complications. Conclusion:RON improved retinal perfusion and achieved a better functional outcome. The measurement of perfusion changes as presented here may be useful for monitoring CRVO and assessing other treatment modalities.
Solubility of Dicalcium Phosphate Dihydrate by Solid Titration
Authors: Pan H.-B. , Darvell B.W.
Published: May 2009

Solid-titration results for hydroxyapatite (HAp), octacalcium phosphate, β-tricalcium phosphate and tetracalcium phosphate have shown that the only stable phase in 100 mmol·l-1 KCl at 37°C is HAp. In particular, dicalcium phosphate dihydrate (DCPD) did not form at pH <4.2 (where it is otherwise believed to be stable) except as a metastable phase under conditions of slight supersaturation. The behaviour of DCPD itself under the same conditions requires checking. Solid titration was used to determine the apparent solubility of DCPD in a 100-mmol·l–1 KCl solution at 37.0 ± 0.1°C over the pH range 3.2–11.6. The constitution of the precipitate was determined by X-ray diffraction, particle morphology was observed by scanning and transmission electron microscopy, and the precipitate Ca/P ratio was calculated by energy-dispersive X-ray analysis. The titration curve for DCPD was substantially lower than the position reported elsewhere. DCPD was the only identified phase at equilibrium at pH 3.60 and 4.50, but HAp was formed after seeding with 1 mg HAp at DCPD equilibrium at pH 4.47, 3.60 and 3.30. It is concluded that the titration curve observed for DCPD corresponds to the solubility isotherm for the phase, but that this represents a metastable equilibrium. HAp is more stable than DCPD, particularly below pH 4.2. The implications for calcium phosphate studies are profound as the reverse is generally believed to be true. Thus, solubility results and the nature of the carious lesion need reconsideration.
Clustering of Unconventional Cardiovascular Risk Factors among Taiwanese Hemodialysis Patients
Authors: Hung Shih-Yuan , Liou Hung-Hsiang , Ger Luo-Ping , Chen Liang-Ken , Liu Mei-Chyn , Chung Hsiao-Min , Chou Kang-Ju , Chen Tso-Hsiao , Lin Chih-Kuang , Yang Yu
Published: May 2009

Background: Cardiovascular disease (CAVD) is the most common cause of mortality for chronic hemodialysis (HD) patients, yet the risk factors for the events have not been well established. Methods: We conducted a multicenter cross-sectional survey in 995 chronic HD patients recruited from 12 HD centers in Taiwan to investigate the prevalence of CAVD, including coronary heart disease (CHD), cerebrovascular disease (CVD), and peripheral vascular disease (PVD), and related them to 30 different parameters. Results: The mean age of 995 patients (499 males/496 females) was 56.4 ± 12.3 years, and average HD duration was 59.8 ± 51.2 months. The prevalence rates of CHD, CVD, and PVD were 24.0, 6.0, and 5.3%, respectively. Results of our multivariate logistic regression analysis showed that out of the conventional CAVD risk factors, only old age and diabetes could be significantly associated with CAVD. Meanwhile, we found some novel clinical correlates, including low apolipoprotein A-I and creatinine for CHD, low uric acid for CVD, and low hematocrit and low diastolic blood pressure for PVD. Interestingly, left ventricular hypertrophy was found to be an independent correlate for all three: CHD, CVD, and PVD. Conclusions: Our study suggests that consideration of conventional cardiovascular risk factors as well as unconventional risk factors might better assess the risk for CAVD among HD patients.
An Exploration of Pre-Service Teachers' Expectations for Their Future Roles
Authors: Wasburn-Moses Leah
Published: May 2009

The diversity of teacher roles has been a long-standing concern in the field of special education. Role complexity has been implicated in teacher burnout and attrition and in the inefficiency of service delivery models. Recent evidence suggests that new policy may be further complicating teacher roles and that teachers may not be prepared for such change. This study is a comparison of 184 preservice special education teachers' expectations for their future roles with the current roles of 133 practicing teachers. In general, pre-service teachers' expectations appeared to be quite accurate. Significant mismatches are revealed in several areas, particularly with respect to collaboration and the settings in which teachers work. Implications are presented for policy makers, administrators, and teacher educators.
Can You Hear Me Now?
Authors: Rock Marcia L. , Gregg Madeleine , Thead Beth K. , Acker Sarah E. , Gable Robert A. , Zigmond Naomi P.
Published: May 2009

In this study, the authors examine whether an advanced online technology can be used to give teacher trainees real-time feedback on their use of research-based classroom practices. Participants include 15 teachers enrolled in a field-based graduate special education teacher preparation program. Data include video-recorded teacher observations and written reflections by teachers about their experiences. Quantitative results indicate that the advanced online bug-in-ear technology is a practical and efficient way to provide immediate feedback to increase teachers' rate of praise statements and their use of proven effective instructional practices and that these improvements are accompanied by increases in students' on-task behavior. Overall, trainees view the advanced online technology as a powerful tool for improving the teaching and learning process but report the need for patience and perseverance in both the teachers and the supervisor, as well as teachers' need for constant reassurance.
Social Actors and Victims of Exploitation
Authors: Abebe Tatek , Kjørholt Anne Trine
Published: May 2009

This article explores the role of children in household livelihoods among the Gedeo ethnic community in Ethiopia. Three themes are discussed — reproductive activities, entrepreneurial work in marketplaces and sociospatial mobility — in the context of recent theoretical debates over children's agency and social competence. With shifts in rural livelihoods, children have developed new agentic and entrepreneurial skills in domestic work, trade and migration. This agency is negotiated in everyday life, but it is also structurally highly circumscribed. Situating children's work within post-rural economic development offers insight into the ways in which regional and global political economy shape their local livelihoods.
Pageant Princesses and Math Whizzes
Authors: Levey Hilary
Published: May 2009

Organized children's activities qualify as children's work, in much the same way that school work does. Both produce transferable use value and create capital that contributes to the future production of goods and services. To illustrate this argument, this article draws on qualitative research primarily based on interviews with the parents of participants in two activities: child beauty pageants and academic enrichment classes. Despite considerable differences in the backgrounds of children who participate in these two types of activities, their parents converge in the reasons they give for enrolling their young children in these activities, and in their focus on their children's future careers and achievements.
Standardized Individual Therapy: a Contradiction in Terms?
Authors: Egelund Tine , Böcker Jakobsen Turf
Published: May 2009

This article explores a paradox that was identified during an ethnographic study of two Danish therapeutic residential institutions for children with emotional and behavioural problems. The key objective of these institutions is to provide specialized treatment for the individual child. However, the task of organizing everyday life for a group of troubled children is so demanding that little room is left for individualization. In practice, treatment takes the shape of a rather standardized package. Analysing individual treatment as a powerful kind of `institutional thinking', the authors delve into the meaning of an apparent contradiction in terms: standardized individual therapy.
Person, Animal, Thing: The 1796 Dog Tax and the Right to Superfluous Things
Authors: Festa Lynn
Published: May 2009

Drawing on Parliamentary debates, print polemics, and satirical prints, this essay traces the rhetorical erosion of seemingly categorical distinctions between human and animal, animate and inanimate, person and thing, in the controversy that arose around the 1796 imposition of a tax on dogs. The passage of this seemingly slight piece of legislation created impassioned debates about the nature and welfare of animals, about the rights of individuals to possess or keep property, and about the way the kinship felt for animals tampers with the seemingly self-evident borders of kind. At a moment in which sentimental humanitarian concern with the rights and interests of animals had reached new heights, the taxation of dogs seemed to reclassify the animal as a thing and to draw into question the relation between humans and their ostensible best friends. Although proponents of the bill endeavor to proceed as if dogs can be considered on the same terms as other kinds of taxable luxuries (devouring resources that might better be devoted to humans), opponents of the tax focus on the bonds of mutual dependency and reciprocal obligation that tie humans and animals together, arguing that the right to keep a beloved entity such as a dog expresses a distinctively human need to keep something beyond mere, bare, necessity. Inasmuch as humanity is expressed and inheres in the relation people take to other creatures, the seeming superfluity of the dog embodies the essence of what allows, or enables, people to act as humans.
Games Policy Makers and Providers Play: Introducing Case-Mix-Based Payment to Hospital Chronic Care Units in Japan
Authors: Ikegami Naoki
Published: May 2009

Case-mix-based payment was developed for hospital chronic care units in Japan to replace the flat per diem rate and encourage the admission of patients with higher medical acuity and was part of a policy initiative to make the tariff more evidence based. However, although the criteria for grouping patients were developed from a statistical analysis of resource use, the tariff was subsequently set below costs, particularly for the groups with the lowest medical acuity, both because of the prime minister's decision to decrease total health expenditures and because of the health ministry's decision to target the reductions on chronic care units. Providers quickly adapted to the new payment system mainly by reclassifying their patients to higher medical acuity groups. Some hospitals reported high prevalence rates of urinary tract infections and pressure ulcers. The government responded by issuing directives to providers to calculate the prevalence rates and document the care that has been mandated for the patients at risk. However, in order to monitor compliance and to evaluate whether the patient is being billed for the appropriate case-mix group, the government must invest in developing a comprehensive patient-level database and in training staff for making on-site inspections.
Community-Based Dialogue: Engaging Communities of Color in the United States' Genetics Policy Conversation
Authors: Bonham Vence L. , Citrin Toby , Modell Stephen M. , Franklin Tené Hamilton , Bleicher Esther W. B. , Fleck Leonard M.
Published: May 2009

Engaging communities of color in the genetics public policy conversation is important for the translation of genetics research into strategies aimed at improving the health of all. Implementing model public participation and consultation processes can be informed by the Communities of Color Genetics Policy Project, which engaged individuals from African American and Latino communities of diverse socioeconomic levels in the process of “rational democratic deliberation” on ethical and policy issues stretching from genome research to privacy and discrimination concerns to public education. The results of the study included the development of a participatory framework based on a combination of the theory of democratic deliberation and the community-based public health model which we describe as “community-based dialogue.”
Gallium(III) Chloride-catalyzed Sakurai Reaction of α-Amido Sulfones with Allyltrimethylsilane: Access to Synthesis of 2,6-Disubstituted Piperidine Alkaloid Derivatives
Authors: Kumar R Sateesh Chandra , Reddy G Venkateswar , Babu K Suresh , Rao J Madhusudana
Published: May 2009

The Sakurai reaction of N-alkoxycarbonylamino sulfones (α-amido sulfones) with allyltrimethylsilane in the presence of gallium(III) chloride (5 mol %) proceeded smoothly to afford the corresponding protected homoallylamines in high yields (82–96%). As an application of this methodology, two-step synthesis of biologically active natural products, 2,6-disubstituted piperidine alkaloid derivatives was carried out.
Face-on and Columnar Porphyrin Assemblies at Solid/Liquid Interface on HOPG
Authors: Otsuki Joe , Namiki Kazuhiko , Arai Yuki , Amano Makoto , Sawai Hirokazu , Tsukamoto Arata , Hagiwara Toshiki
Published: May 2009

Porphyrins having alkyl chains, each of which contains a diacetylene unit, were prepared to examine their self-assembled structures at the liquid/solid interface on graphite. The porphyrins with the longest alkyl chains form a face-on arrangement on the surface, while those with shorter alkyl chains form highly ordered one-dimensional columns. This work demonstrates that introducing a structural perturbation in the alkyl chain is a useful strategy to obtain novel surface assemblies.
The Effect of Zn Addition to La1−xSrxScO3−δ Systems as a B-site Dopant
Authors: Ito Naoki , Matsumoto Hiroshige , Kawasaki Yuya , Okada Sachio , Ishihara Tatsumi
Published: May 2009

Zn was introduced to La1−xSrxScO3−δ as a B-site dopant. The addition of Zn markedly improved the sinterability of the material, and a dense sinter could be synthesized by a solid-state reaction method. Although conductivity was slightly decreased by the addition of Zn, it was shown that La1−xSrxSc1−yZnyO3−δ is a useful electrolyte material for intermediate-temperature fuel cells.
TEMPO-based Redox-sensitive Fluorescent Probes and Their Applications to Evaluating Intracellular Redox Status in Living Cells
Authors: Liu Yang , Liu Shanlin , Wang Yanguang
Published: May 2009

Two redox-sensitive fluorescent probes were developed for evaluating the intracellular redox status of living cells as a complement to the widely used dye 2′,7′-dichlorodihydrofluorescein (DCFH).
A Low-Cost System for the Grading of Kiwifruit
Authors: Osborne Scott D. , Künnemeyer Rainer , Jordan Robert B.
Published: May 2009

A low cost NIR spectrometer has been used to estimate the soluble solids and dry matter content of kiwifruit non-destructively at reasonably high speed. PLS regression in conjunction with wavelength selection provided models with a root mean square error of cross validation of 0.27°Brix for soluble solids and 0.32% for dry matter. These errors are well below previously published results and would allow the grading of kiwifruit by internal quality into a number of classes with distinctly different taste attributes. The time required for data capture has been reduced to 0.75s per fruit by decreasing the noise introduced through the measurement procedure or the equipment. Based on the current performance of the equipment and process it appears feasible to increase the speed to about 10 fruit per second without detrimental change to signal-to-noise ratio or predictive capability for soluble solids and dry matter, opening the possibility for on-line grading of these properties.
Portability of near Infrared Spectroscopic Calibrations for Petrochemical Parameters
Authors: Hoffmann Uwe , Zanier-Szydlowski Nathalie
Published: May 2009

The purpose of this paper is to analyse the origin of the differences in spectral response between different Fourier transform near infrared spectrometers of the same type. The influence of the sample and room temperatures is analysed and the importance of the field of view at the sampling accessory and of the near infrared lamp alignment is demonstrated. The performances of a Shenk–Westerhaus type correction have been demonstrated on seven PLS1 models predicting different physico-chemical properties of hydrotreated gas oils. The bias in the transfer of these models from one system to another was equivalent to the repeatability of analysis for a single system. Nevertheless, it has been shown that this type of standardisation algorithm compensates a frequency shift of 0.32 cm−1 by intensity correction. Spectrometers characterised by a reproducibility in intensity of the order of ± 0.002 absorbance units (in the frequency range 6400–5500 cm−1, with a 2 mm cell) and a wavenumber reproducibility of ± 0.04 cm−1 show no need for calibration transfer with a sample temperature controlled at ± 0.5°C.
Bridging the Continuum–Discontinuum Gap in the Theory of Diffuse Reflectance
Authors: Dahm Donald J. , Dahm Kevin D.
Published: May 2009

A system of equations described by Benford relate the absorption and remission properties of a layer of a material to the properties of any other thickness of the material. R, the fraction of light remitted from an infinitely thick sample, may be calculated from Benford's equations by increasing the sample thickness until the total remission converges to its upper limit. The fractions of light absorbed ( a0) and remitted ( r0) by a very thin layer may be similarly calculated. The relationship A( r,t) = [(1 – r)2 – t2] / r = (2 – a – 2 r) a / r = 2 a0 / r0 = (1 – R)2 / R describes an Absorption/Remission Function for the material as a function of a, r and t, the fractions of light absorbed, remitted and transmitted by a specified layer. This is a more general expression than the widely used Kubelka–Munk equation, but gives results equivalent to it for the case of infinitesimal particles.