bluuebunny/crossref_metadata_2025 huggingface dataset:
Phylogeography of Spiraea alpina (Rosaceae) in the Qinghai–Tibetan Plateau inferred from chloroplast DNA sequence variations
Authors: ZHANG Fa‐Qi , GAO Qing‐Bo , ZHANG De‐Jun , DUAN Yi‐Zhong , LI Yin‐Hu , FU Peng‐Cheng , XING Rui , GULZAR Khan , CHEN Shi‐Long
Published: April 2012

Abstract  The aim of the present study was to investigate the phylogeographic patterns of Spiraea alpina (Rosaceae) and clarify its response to past climatic changes in the climate‐sensitive Qinghai‐Tibetan Plateau (QTP). We sequenced a chloroplast DNA fragment (trnL–trnF) from 528 individuals representing 43 populations. We identified 10 haplotypes, which were tentatively divided into three groups. These haplotypes or groups were distributed in the different regions of the QTP. Only half the populations were fixed by a single haplotype, whereas the others contained two or more. In the central and eastern regions, adjacent populations at the local scale shared the same haplotype. Our phylogeographic analyses suggest that this alpine shrub survived in multiple refugia during the Last Glacial Maximum and that earlier glaciations may have trigged deep intraspecific divergences. Post‐glacial expansions occurred only within populations or across multiple populations within a local range. The findings of the present study together with previous phylogeographic reports suggest that evolutionary histories of plants in the QTP are complex and variable depending on the species investigated.
Endothelin‐1 derived from spleen‐activated Rho‐kinase pathway in rats with secondary biliary cirrhosis
Authors: Uehara Hideo , Akahoshi Tomohiko , Kawanaka Hirohumi , Hashimoto Naotaka , Nagao Yoshihiro , Tomikawa Morimasa , Taketomi Akinobu , Shirabe Ken , Hashizume Makoto , Maehara Yoshihiko
Published: April 2012

Aim:  Splenectomy or partial splenic embolism has been reported to improve liver function in patients with hypersplenism and liver dysfunction. The aim of this study was to investigate the mechanism of improvement after splenectomy.

Methods:  Liver cirrhosis was induced by bile duct ligation (BDL). Rats underwent sham operation, splenectomy (Sp group), BDL, or BDL plus splenectomy (BDL + Sp group), and were subjected to experiments at 2 weeks after the operation. Portal venous pressure (PVP) and hepatic tissue blood flow (HTBF) were measured in each group. The plasma concentration of endothelin‐1 (ET‐1) and endothelial nitric oxide synthase (eNOS), RhoA and Rho‐kinase expressions were studied.

Results:  There were significant differences in PVP (17.9 ± 0.91 vs 23.3 ± 3.91 cmH2O; P < 0.01) and HTBF (16.6 ± 1.72 vs 13.3 ± 1.82 mL/min; P < 0.01) between the BDL + Sp and BDL groups. In the liver of BDL rats, eNOS phosphorylation and NOx levels were decreased, accompanied by RhoA activation compared with the BDL + Sp group. Splenectomy decreased serum ET‐1 levels, RhoA activation and consequently increased eNOS phosphorylation.

Conclusion:  ET‐1 derived from the spleen might increase intrahepatic resistance by downregulating Rho signaling in liver cirrhosis. Splenectomy for splenomegaly in liver cirrhosis might partially improve liver function by enhancing intrahepatic microcirculation.
Impact of Reseller's Forecasting Accuracy on Channel Member Performance
Authors: Chen Ying‐Ju , Xiao Wenqiang
Published: April 2012

This article studies a three‐layer supply chain where a manufacturer sells a product through a reseller who then relies on its own salesperson to sell to the end market. The reseller has superior capability in demand forecasting relative to the manufacturer. We explore the main trade‐offs between the risk‐reduction effect and the information–asymmetry–aggravation effect of the improved forecasting accuracy. We show that under the optimal wholesale price contract, both the manufacturer and the reseller are always better off as the reseller's forecasting accuracy improves. Nevertheless, under the menu of two‐part tariffs, the manufacturer prefers the reseller to be either uninformed or perfectly informed about the market condition. We further find that the improved forecasting accuracy is beneficial for the reseller if its current forecasting system is either very poor or very good.
Does Quality Still Pay? A Reexamination of the Relationship Between Effective Quality Management and Firm Performance
Authors: Zhang Guoqiang Peter , Xia Yusen
Published: April 2012

Because of the changing competitive environment, quality might have lost some of its luster and emphasis in business. The research question we aim to address in this paper is: Does quality still pay in the new competitive environment? Using replication research, we re‐examine the impact of an effective total quality management (TQM) program on a firm's operating performance in the new competitive environment. We use publicly available data for award‐winning firms and adopt several control‐firm‐selection approaches in our event study. Based on data from more than 500 firms, we find that over a 10‐year period—6 years before to 3 years after winning their first quality award—firms in our sample perform significantly better than control groups in various operating performance measures. Not only do award‐winning firms have better results after receiving awards, they also have superior performance records before the award. Our results suggest that quality is still critical to achieving long‐term competitive advantages, and firms who continuously improve their quality continue to reap rewards by way of sales and financial performances exceeding those of their competitors.
Design of Stockless Production Systems
Authors: Arreola‐Risa Antonio , Keblis Matthew F.
Published: April 2012

In make‐to‐stock production systems finished goods are produced in anticipation of demand. By contrast, in stockless production systems finished goods are not produced until demand is observed. In this study we investigate the problem of designing a multi‐item manufacturing system, where there is both demand‐ and production‐related uncertainty, so that stockless operation will be optimal for all items. For the problem of interest, we focus on gaining an understanding of the effect of two design variables: (i) manufacturing speed—measured by the average manufacturing rate or, equivalently, the average unit manufacturing time, and (ii) manufacturing consistency—measured by the variation in unit manufacturing times. We establish conditions on these two variables that decision makers can use to design stockless production systems. Managerial implications of the conditions are also discussed.
An Enhanced Concave Program Relaxation for Choice Network Revenue Management
Authors: Meissner Joern , Strauss Arne , Talluri Kalyan
Published: April 2012

The network choice revenue management problem models customers as choosing from an offer set, and the firm decides the best subset to offer at any given moment to maximize expected revenue. The resulting dynamic program for the firm is intractable and approximated by a deterministic linear program called the CDLP which has an exponential number of columns. However, under the choice‐set paradigm when the segment consideration sets overlap, the CDLP is difficult to solve. Column generation has been proposed but finding an entering column has been shown to be NP‐hard. In this study, starting with a concave program formulation called SDCP that is based on segment‐level consideration sets, we add a class of constraints called product constraints ( σPC), that project onto subsets of intersections. In addition, we propose a natural direct tightening of the SDCP called [Formula: see text], and compare the performance of both methods on the benchmark data sets in the literature. In our computational testing on the data sets, 2 PC achieves the CDLP value at a fraction of the CPU time taken by column generation. For a large network our 2 PC procedure runs under 70 seconds to come within 0.02% of the CDLP value, while column generation takes around 1 hour; for an even larger network with 68 legs, column generation does not converge even in 10 hours for most of the scenarios while 2 PC runs under 9 minutes. Thus we believe our approach is very promising for quickly approximating CDLP when segment consideration sets overlap and the consideration sets themselves are relatively small.
Oxygen Partial Pressure Dependence of In Situ X-Ray Absorption Spectroscopy at Co and Fe K-Edge for (La0.6Sr0.4)(Co0.2Fe0.8)O3–δ
Authors: Itoh Takanori , Shirasaki Saori , Ofuchi Hironori , Hirayama Sayaka , Honma Tetsuo , Mori Masashi , Nakayama Masanobu
Published: April 2012

(La0.6Sr0.4)(Co0.2Fe0.8)O3–δ (LSCF) has been promised as a cathode material of solid oxide fuel cells at intermediate temperatures. Despite the many previous studies of LSCF that have been reported, the role of Co and Fe atoms in the oxygen ion conduction is still unclear. In this work, we aimed at presenting each valence, oxygen chemical diffusion coefficient (Dchem) and activation energy (Ea) related to Co and Fe in LSCF by in situ X-ray absorption spectroscopy (XAS) at high temperatures and during reduction. For quantitative analysis of X-ray absorption near edge structure (XANES) spectroscopy, these results indicated that the Co valence decreased more easily than the Fe valence. On the other hand, from relaxation plots of the Co and Fe valence during reduction, the values of Dchem and Ea related to Co and Fe were nearly equal. Considering equations showing the oxygen ion conductivity, these results would indicate that oxygen ion conductivity was contributed by Co with more oxygen vacancies rather than Fe. According to these results, a structural model with and without oxygen vacancies and the oxygen ion conduction mechanism of LSCF was speculated, that is, we found that oxygen ion conductivity was more closely related to Co than Fe in LSCF by direct observations of in situ XAS.
Exergy Analysis of Different Cold End Configurations for Helium Liquefiers
Authors: Thomas Rijo Jacob , Ghosh Parthasarathi , Chowdhury Kanchan
Published: April 2012

Cold end in helium liquefiers, where finally the gas is converted to liquid, may have different alternatives in configuration to achieve maximum exergy efficiency. Apart from high exergy efficiency, which also means low specific power consumption, reliability of operation and complexity of equipment design are also some of the concerns for designers. In this work, various cold end configurations are compared at different operating conditions to help arrive at appropriate choices during design and operation. When single Joule–Thomson valve is replaced by more efficient cold ends with expanders, it allows reduction of the number of Brayton stages in precooling section as well as the total heat exchanger size. Cold end with expander and Joule–Thomson valve combination has been found to be a good compromise between reliability, liquid production, specific power consumption, and exergy efficiency. However, for such a configuration, it is important to fix the intermediate pressure at appropriate level so as to avoid liquid formation at the exit of the expander.
Enhanced Miniature Loop Heat Pipe Cooling System for High Power Density Electronics
Authors: Choi J. H. , Sung B. H. , Yoo J. H. , Kim C. J. , Borca-Tasciuc D.-A.
Published: April 2012

The implementation of high power density, multicore central and graphic processing units (CPUs and GPUs) coupled with higher clock rates of the high-end computing hardware requires enhanced cooling technologies able to attend high heat fluxes while meeting strict design constrains associated with system volume and weight. Miniature loop heat pipes (mLHP) emerge as one of the technologies best suited to meet all these demands. Nonetheless, operational problems, such as instable behavior during startup on evaporator side, have stunted the advent of commercialization. This paper investigates experimentally two types of mLHP systems designed for workstation CPUs employing disk shaped and rectangular evaporators, respectively. Since there is a strong demand for miniaturization in commercial applications, emphasis was also placed on physical size during the design stage of the new systems. One of the mLHP system investigated here is demonstrated to have an increased thermal performance at a reduced system weight. Specifically, it is shown that the system can reach a maximum heat transfer rate of 170 W with an overall thermal resistance of 0.12 K/W. The corresponding heat flux is 18.9 W/cm2, approximately 30% higher than that of larger size commercial systems. The studies carried out here also suggest that decreasing the thermal resistance between the heat source and the working fluid and maximizing the area for heat transfer are keys for obtaining an enhanced thermal performance.
Stack Operation Using Composite Membrane-Electrodes Assemblies at 120ÃÂ °C
Authors: Giacoppo G. , Carbone A. , Gatto I. , Saccà A. , Pedicini R. , Barbera O. , Passalacqua E.
Published: April 2012

A 500 W stack operating at medium temperatures was designed, manufactured and tested. Nanocomposite Nafion membranes/electrodes (MEA1-NZr) assemblies, containing a commercial yttria stabilized zirconia (YSZ) as a filler, were developed to work over 80ÃÂ °C. A 100 cm2 cell active area with a parallel serpentine flow field as reactants distributor was used for stack realization. Preliminary electrochemical tests in a single cell and in two-cells short stack were performed at 120ÃÂ °C, 3 barabs and fully hydrated gases, reaching a rated power at 50 A of about 30W in single cell and 70W in short stack. Finally, a 20 cells stack was assembled, with composite MEA-NZr, and tested at 120ÃÂ °C, 3 barabs and partially humidified gases. In these conditions, a power of 433 W at 50 A was reached. Comparing these results with the short stack performance at the same current (50 A), a 24% of power loss, which corresponds to 7 W/cell, was recorded. This performance reduction could be explained considering the scale up effect passing from 2-cells to 20-cells stack. The obtained results show that the developed composite membrane-electrodes assemblies and the designed stack are suitable for working at higher temperature than traditional polymer electrolyte membrane fuel cells.
Waste Heat Recovery in Data Centers Using Sorption Systems
Authors: Little Adrienne B. , Garimella Srinivas
Published: April 2012

Of the total electricity consumption by the United States in 2006, more than 1% was used on data centers alone; a value that continues to rise rapidly. Of the total amount of electricity a data center consumes, about 30% is used to cool server equipment. The present study conceptualizes and analyzes a novel paradigm consisting of integrated power, cooling, and waste heat recovery and upgrade systems that considerably lower the energy footprint of data centers. Thus, on-site power generation equipment is used to supply primary electricity needs of the data center. The microturbine-derived waste heat is recovered to run an absorption chiller that supplies the entire cooling load of the data center, essentially providing the requisite cooling without any additional expenditure of primary energy. Furthermore, the remaining waste heat rejected by the data center is boosted to a higher temperature with a heat transformer, with the upgraded thermal stream serving as an additional output of the data center with negligible additional electrical power input. Such upgraded heat can be used for district heating applications in neighboring residential or commercial buildings, or as process heat for commercial end uses such as laundries, hospitals, and restaurants, depending on the location of the data center. With such a system, the primary energy usage of the data center as a whole can be reduced by up to 23% while still addressing the high-flux cooling loads, in addition to providing a new income stream through the sales of upgraded thermal energy. Given the large and fast-escalating energy consumption patterns of data centers, this novel, integrated approach to electricity and cooling supply, and waste heat recovery and upgrade will substantially reduce primary energy consumption for this important end use worldwide.
Modeling Study of Anode Water Flooding and Gas Purge for PEMFCs
Authors: Zhai Shuang , Zhou Su , Sun Pengtao , Chen Fengxiang , Niu Jigao
Published: April 2012

A one-dimensional, dynamic proton exchange membrane fuel cells stack model is developed in this paper, where the transports of reactant and water (in both liquid and vapor phase) are described by partial differential equations (PDEs) in gas diffusion layers (GDLs) of both anode and cathode, and the lumped model is applied to channels and MEA. The boundary conditions needed for PDEs in GDLs are provided by the lumped model. In addition, the convection term is considered in PDEs for GDLs to describe the convection effect on hydrogen gas purge process on the anode side. As a result, the purge effect under medium current density (corresponding to ohmic polarization dominated region) can be simulated in an efficient manner by improving the mass transfer and reducing the effect of water back diffusion from cathode to anode. The presented gas purge model is validated by the experimental data obtained from our laboratory as well as other research group. The influence factors to the gas purge schedule on the anode side, such as the purge interval and purge time, are investigated as well.
Heat Spreader Based on Room-Temperature Liquid Metal
Authors: Deng Yueguang , Liu Jing
Published: April 2012

This study reports a high-performance heat spreader based on room-temperature liquid metal coolant. Conceptual cooling experiments show that liquid metal heat spreader owns particularly excellent heat spreading performance. In order to evaluate the driving features of liquid metal, a miniaturized electromagnetic pump with high reliability and low power consumption was fabricated and tested. Extreme experiments were performed and showed that liquid metal heat spreader could overwhelm all the latest typical advanced spreading technologies and serve as an ultimate heat spreading solution under extremely high heat flux density condition.
High Intensity Drying in Porous Materials
Authors: Chaitanya Pakala V. K. , Plumb O. A.
Published: April 2012

High intensity drying is used to characterize those situations for which the drying medium is sufficiently above the saturation temperature of water to preclude the existence of a two-phase zone. In the present work, three models are applied to high intensity drying of porous materials. The three models are: (1) a traditional one-equation model that assumes local thermal equilibrium (LTE); (2) a two-equation model that utilizes lumped capacitance assumption to predict the heat transfer to the solid phase; and (3) a two-equation model that utilizes a more precise quasi-analytical approach to more accurately characterize the conduction in the solid phase. In addition, the relationship between pressure and the drying conditions and material properties is examined since elevated pressure that can occur during high intensity drying is potentially destructive. An implicit finite difference scheme is utilized to determine the drying rate in a porous medium saturated with water and undergoing the phase change process. The case for low local Reynolds number is considered, hence Nusselt number is assumed constant. Results illustrate that the one-equation model does not yield accurate results when the thermophysical properties characterized by the volume weighted ratio of thermal diffusivities, C > 10 (within 5% error). Hence, a two-equation model is suggested. In addition, consistent with the established “rule of thumb,” for Biot number, Biv < 0.1, the traditional two-equation model which makes the lumped capacitance assumption for the solid phase compares well with a two-equation model that more accurately predicts the time dependent diffusion in the solid phase using Duhamel’s theorem. The peak pressures observed during drying for a range of Darcy number and surface heat flux are presented.
Mixing Analysis in a Lid-Driven Cavity Flow at Finite Reynolds Numbers
Authors: Rao Pradeep , Duggleby Andrew , Stremler Mark A.
Published: April 2012

The influence of inertial effects on chaotic advection and mixing is investigated for a two-dimensional, time-dependent lid-driven cavity flow. Previous work shows that this flow exhibits exponential stretching and folding of material lines due to the presence of figure-eight stirring patterns in the creeping flow regime. The high sensitivity to initial conditions and the exponential growth of errors in chaotic flows necessitate an accurate solution of the flow in order to calculate metrics based on Lagrangian particle tracking. The streamfunction-vorticity formulation of the Navier-Stokes equations is solved using a Fourier-Chebyshev spectral method, providing the necessary exponential convergence and machine-precision accuracy. Poincaré sections and mixing measures are used to analyze chaotic advection and quantify the mixing efficiency. The calculated mixing characteristics are almost identical for Re ≤ 1. For the time range investigated, the best mixing in this system is observed for Re = 10. Interestingly, increasing the Reynolds number to the range 10 < Re ≤ 100 results in an observed decrease in mixing efficacy.
Computational Fluid
Dynamics Modeling of Benjamin and Taylor Bubbles in Two-Phase Flow in
Pipes
Authors: Ramdin M. , Henkes Ruud
Published: April 2012

There is an increasing interest in applying three-dimensional computational fluid dynamics (CFD) for multiphase flow transport in pipelines, e.g., in the oil and gas industry. In this study, the volume of fluid (VOF) multiphase model in a commercial CFD code was used to benchmark the capabilities. Two basic flow structures, namely, the Benjamin bubble and the Taylor bubble, are considered. These two structures are closely related to the slug flow regime, which is a common flow pattern encountered in multiphase transport pipelines. After nondimensionalization, the scaled bubble velocity (Froude number) is only dependent on the Reynolds number and on the Eötvös number, which represent the effect of viscosity and surface tension, respectively. Simulations were made for a range of Reynolds numbers and Eötvös numbers (including the limits of vanishing viscosity and surface tension), and the results were compared with the existing experiments and analytical expressions. Overall, there is very good agreement. An exception is the simulation for the 2D Benjamin bubble at a low Eötvös number (i.e., large surface tension effect) which deviates from the experiments, even at a refined numerical grid.
Internal Flow and Axial Thrust Balancing of a Rocket Pump
Authors: Shimura Takashi , Kawasaki Satoshi , Uchiumi Masaharu , Kimura Toshiya , Matsui Jun
Published: April 2012

Large axial thrust is produced on the rotor assembly of high-pressure rocket pumps. Thus, to ensure the reliability of bearings supporting the high rotational speed rotor, precise axial thrust balancing is essential. To realize complete axial thrust balancing, the back shroud of the main impeller is employed as the balance piston of a self-balancing type axial thrust balancing system in which the rotor assembly moves axially to compensate unbalance axial force. In this balancing system, which is often applied, complicated internal flow characteristics and pressure distributions are very important for predicting the precise characteristics of the axial thrust produced by the system. In the present study, a calculation method for analyzing the internal flow system taking into account effects of boundary layer conditions and angular momentum change in the impeller side-chambers is applied to the system combining the balance piston and grooves on the casing wall of the balance piston chamber. The analysis program is able to detect phenomena which could not be captured in past calculations and is effective for calculating internal flow characteristics much faster than possible with CFD analysis. A combination of balance piston and grooves on the casing wall of the balance piston chamber was confirmed to be suitable for extending the dynamic range of axial thrust balancing although installation of the grooves increased the leakage flow rate and friction torque at the same time.
High Mortality Associated with Catabacter hongkongensis Bacteremia
Authors: Lau Susanna K. P. , Fan Rachel Y. Y. , Lo Hoo-Wing , Ng Ricky H. Y. , Wong Samson S. Y. , Li Iris W. S. , Wu Alan K. L. , Ng Kenneth H. L. , Tseung Steven , Lee Rodney A. , Fung Kitty S. C. , Que Tak-Lun , Yuen Kwok-Yung , Woo Patrick C. Y.
Published: April 2012

Catabacter hongkongensis
is a recently described catalase-positive, motile, anaerobic, nonsporulating, Gram-positive coccobacillus that was first isolated from blood cultures of four patients from Hong Kong and Canada. Although DNA sequences representing
C. hongkongensis
have been detected in environmental sources, only one additional case of human infection has been reported, in France. We describe five cases of
C. hongkongensis
bacteremia in Hong Kong, two presenting with sepsis, one with acute gangrenous perforated appendicitis, one with acute calculous cholecystitis, and one with infected carcinoma of colon. Three patients, with gastrointestinal malignancy, died during admission. All five isolates were catalase positive, motile, and negative for indole production and nitrate reduction and produced acid from arabinose, glucose, mannose, and xylose. They were unambiguously identified as
C. hongkongensis
by 16S rRNA gene analysis. Of the total of 10 reported cases of
C. hongkongensis
bacteremia in the literature and this study, most patients had underlying diseases, while two cases occurred in healthy young individuals with acute appendicitis. Six patients presented with infections associated with either the gastrointestinal or biliary tract, supporting the gastrointestinal tract as the source of bacteremia.
C. hongkongensis
bacteremia is associated with a poor prognosis, with a high mortality of 50% among reported cases, especially in patients with advanced malignancies. All reported isolates were susceptible to metronidazole. Identification of more
C. hongkongensis
isolates by 16S rRNA gene sequencing will help better define its epidemiology and pathogenesis.
Rapid Detection of
rpoB
Gene Mutations Conferring Rifampin Resistance in Mycobacterium tuberculosis
Authors: Ao Wanyuan , Aldous Stephen , Woodruff Evelyn , Hicke Brian , Rea Larry , Kreiswirth Barry , Jenison Robert
Published: April 2012

Multidrug-resistant
Mycobacterium tuberculosis
strains are widespread and present a challenge to effective treatment of this infection. The need for a low-cost and rapid detection method for clinically relevant mutations in
Mycobacterium tuberculosis
that confer multidrug resistance is urgent, particularly for developing countries. We report here a novel test that detects the majority of clinically relevant mutations in the beta subunit of the RNA polymerase (
rpoB
) gene that confer resistance to rifampin (RIF), the treatment of choice for tuberculosis (TB). The test, termed TB ID/R, combines a novel target and temperature-dependent RNase H2-mediated cleavage of blocked DNA primers to initiate isothermal helicase-dependent amplification of a
rpoB
gene target sequence. Amplified products are detected by probes arrayed on a modified silicon chip that permits visible detection of both RIF-sensitive and RIF-resistant strains of
M. tuberculosis
. DNA templates of clinically relevant single-nucleotide mutations in the
rpoB
gene were created to validate the performance of the TB ID/R test. Except for one rare mutation, all mutations were unambiguously detected. Additionally, 11 RIF-sensitive and 25 RIF-resistant clinical isolates were tested by the TB ID/R test, and 35/36 samples were classified correctly (96.2%). This test is being configured in a low-cost test platform to provide rapid diagnosis and drug susceptibility information for TB in the point-of-care setting in the developing world, where the need is acute.
Cytology and Human Papillomavirus Testing 6 to 12 Months after ASCUS or LSIL Cytology in Organized Screening To Predict High-Grade Cervical Neoplasia between Screening Rounds
Authors: Tropé Ameli , Sjøborg Katrine D. , Nygård Mari , Røysland Kjetil , Campbell Suzanne , Alfsen G. Cecilie , Jonassen Christine M.
Published: April 2012

We carried out a prospective study comparing the performance of human papillomavirus (HPV) E6/E7 mRNA (PreTect HPV-Proofer; NorChip, Klokkarstua, Norway) and DNA (Amplicor HPV test; Roche Diagnostics, Basel, Switzerland) triage testing of women 6 to 12 months after atypical-squamous-cells-of-undetermined-significance (ASCUS) or low-grade-squamous-intraepithelial-lesion (LSIL) cytology in organized screening to predict high-grade cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) between screening rounds. Between January 2005 and April 2008, 692 study women with screening-detected ASCUS/LSIL cytology 6 to 12 months earlier returned for HPV mRNA and DNA testing and repeat cytology. The median follow-up time was 3 years, using existing health care facilities. Follow-up test results were available for 625 women. Of the 145 CIN2+ cases detected during the study period, 95 (65.5%) were HPV mRNA positive 6 to 12 months after screening-detected ASCUS/LSIL, 44 (30.4%) were HPV mRNA negative, and 6 (4.1%) were invalid. The corresponding HPV DNA results were 139 (95.9%), 5 (3.4%), and 1 (0.7%), respectively. The cumulative incidences of CIN2+ 3 years after a negative HPV mRNA and DNA test were 10.3% (95% confidence interval [CI], 7.2 to 13.3%) and 1.8% (95% CI, 0.0 to 3.6%), respectively. The cumulative incidences of CIN2+ 3 years after positive HPV mRNA and DNA tests were 52.8% (95% CI, 40.1 to 60.1%) and 41.3% (95% CI, 35.5 to 46.6%), respectively. In conclusion, both positive HPV mRNA and DNA test results have a high enough long-term prediction of CIN2+ risk to consider referral to colposcopy as good practice when performed in delayed triage of women with ASCUS/LSIL cytology. In addition, the low CIN2+ risk among women with a negative Amplicor HPV test in our study confirms its safe use in a clinical setting.
Comparison of the Abbott RealTi
m
e High-Risk Human Papillomavirus (HPV), Roche Cobas HPV, and Hybrid Capture 2 Assays to Direct Sequencing and Genotyping of HPV DNA
Authors: Park Yongjung , Lee Eunhee , Choi Jonghyeon , Jeong Seri , Kim Hyon-Suk
Published: April 2012

Infection with high-risk (HR) human papillomavirus (HPV) genotypes is an important risk factor for cervical cancers. We evaluated the clinical performances of two new real-time PCR assays for detecting HR HPVs compared to that of the Hybrid Capture 2 test (HC2). A total of 356 cervical swab specimens, which had been examined for cervical cytology, were assayed by Abbott RealTi
m
e HR and Roche Cobas HPV as well as HC2. Sensitivities and specificities of these assays were determined based on the criteria that concordant results among the three assays were regarded as true-positive or -negative and that the results of genotyping and sequencing were considered true findings when the HPV assays presented discrepant results. The overall concordance rate among the results for the three assays was 82.6%, and RealTi
m
e HR and Cobas HPV assays agreed with HC2 in 86.1% and 89.9% of cases, respectively. The two real-time PCR assays agreed with each other for 89.6% of the samples, and the concordance rate between them was equal to or greater than 98.0% for detecting HPV type 16 or 18. HC2 demonstrated a sensitivity of 96.6% with a specificity of 89.1% for detecting HR HPVs, while RealTi
m
e HR presented a sensitivity of 78.3% with a specificity of 99.2%. The sensitivity and specificity of Cobas HPV for detecting HR HPVs were 91.7% and 97.0%. The new real-time PCR assays exhibited lower sensitivities for detecting HR HPVs than that of HC2. Nevertheless, the newly introduced assays have an advantage of simultaneously identifying HPV types 16 and 18 from clinical samples.
Evaluation of Macrolide Resistance and Enhanced Molecular Typing of Treponema pallidum in Patients with Syphilis in Taiwan: a Prospective Multicenter Study
Authors: Wu Hsiu , Chang Sui-Yuan , Lee Nan-Yao , Huang Wen-Chi , Wu Bing-Ru , Yang Chia-Jui , Liang Shiou-Haur , Lee Chen-Hsiang , Ko Wen-Chien , Lin Hsi-Hsun , Chen Yen-Hsu , Liu Wen-Chun , Su Yi-Ching , Hsieh Chia-Yin , Wu Pei-Ying , Hung Chien-Ching
Published: April 2012

Studies of macrolide resistance mutations and molecular typing using the newly proposed enhanced typing system for
Treponema pallidum
isolates obtained from HIV-infected patients in the Asia-Pacific region are scarce. Between September 2009 and December 2011, we conducted a survey to detect
T. pallidum
using a PCR assay using clinical specimens from patients with syphilis at six major designated hospitals for HIV care in Taiwan. The
T. pallidum
strains were genotyped by following the enhanced molecular typing methodology, which analyzed the number of 60-bp repeats in the acidic repeat protein (
arp
) gene,
T. pallidum
repeat (
tpr
) polymorphism, and the sequence of base pairs 131 to 215 in the
tp0548
open reading frame of
T. pallidum
. Detection of A2058G and A2059G point mutations in the
T. pallidum
23S rRNA was performed with the use of restriction fragment length polymorphism (RFLP). During the 2-year study period, 211 clinical specimens were obtained from 136 patients with syphilis.
T. pallidum
DNA was isolated from 105 (49.8%) of the specimens, with swab specimens obtained from chancres having the highest yield rate (63.2%), followed by plasma (49.4%), serum (35.7%), and cerebrospinal fluid or vitreous fluid (18.2%) specimens. Among the 40 fully typed specimens, 11 subtypes of
T. pallidum
were identified. Subtype 14f/f (18 isolates) was the most common isolates, followed by 14f/c (3), 14b/c (3), and 14k/f (3). Among the isolates examined for macrolide resistance, none had the A2058G or A2059G mutation. In conclusion, we found that type 14 f/f was the most common
T. pallidum
strain in this multicenter study on syphilis in Taiwan and that none of the isolates exhibited 23S rRNA mutations causing resistance to macrolides.
Early Diagnosis of
In Utero
and Intrapartum HIV Infection in Infants Prior to 6 Weeks of Age
Authors: Lilian Rivka R. , Kalk Emma , Bhowan Kapila , Berrie Leigh , Carmona Sergio , Technau Karl , Sherman Gayle G.
Published: April 2012

Early initiation of antiretroviral therapy reduces HIV-related infant mortality. The early peak of pediatric HIV-related deaths in South Africa occurs at 3 months of age, coinciding with the earliest age at which treatment is initiated following PCR testing at 6 weeks of age. Earlier diagnosis is necessary to reduce infant mortality. The performances of the Amplicor DNA PCR, COBAS AmpliPrep/COBAS TaqMan (CAP/CTM), and Aptima assays for detecting early HIV infection (acquired
in utero
and intrapartum) up to 6 weeks of age were compared. Dried blood spots (DBS) were collected at birth and at 2, 4, and 6 weeks from HIV-exposed infants enrolled in an observational cohort study in Johannesburg, South Africa. HIV status was determined at 6 weeks by DNA PCR on whole blood. Serial DBS samples from all HIV-infected infants and two HIV-uninfected, age-matched controls were tested with the 3 assays. Of 710 infants of known HIV status, 38 (5.4%) had
in utero
(
n
= 29) or intrapartum (
n
= 9) infections. By 14 weeks, when treatment should have been initiated, 13 (45%)
in utero
-infected and 2 (22%) intrapartum-infected infants had died or were lost to follow-up. The CAP/CTM and Aptima assays identified 76.3% of all infants with early HIV infections at birth and by 4 weeks were 96% sensitive. DNA PCR demonstrated lower sensitivities at birth and 4 weeks of 68.4% and 87.5%, respectively. All assays had the lowest sensitivity at 2 weeks of age. CAP/CTM was the only assay with 100% specificity at all ages. Testing at birth versus 6 weeks of age identifies a higher total number of HIV-infected infants, irrespective of the assay.
Detection of Methicillin-Resistant Staphylococcus aureus in Clinical Specimens from Cystic Fibrosis Patients by Use of Chromogenic Selective Agar
Authors: Perez Leandro Reus Rodrigues , Antunes Ana Lúcia Souza , Bonfanti Jéssica Weiss , Pinto Jaqueline Becker , Roesch Eliane Wurdig , Rodrigues Diógenes , Dias Cícero Armídio Gomes
Published: April 2012

We evaluated the use of a chromogenic selective medium (MRSA ID) as a useful tool for the detection of methicillin-resistant
Staphylococcus aureus
(MRSA) in cystic fibrosis (CF) patient samples. Fifty-four MRSA isolates were detected by MRSA ID, while only 24/54 (44%) (odds ratio [OR], 2.79; 95% confidence interval [CI], 1.63 to 4.76) were detected by conventional methods. A chromogenic selective medium for MRSA detection may improve its surveillance in CF patients.
OXA-163-Producing Klebsiella pneumoniae in Cairo, Egypt, in 2009 and 2010
Authors: Abdelaziz Mohammed O. , Bonura Celestino , Aleo Aurora , El-Domany Ramadan A. , Fasciana Teresa , Mammina Caterina
Published: April 2012

Two genetically unrelated OXA-163-carrying
Klebsiella pneumoniae
strains were identified from two infection cases in June 2009 and May 2010 in Cairo, Egypt. OXA-163-producing
Enterobacteriaceae
had been previously reported in Argentina only. Both patients had no history of travel abroad. The emergence of this newly recognized OXA-48-related β-lactamase able to hydrolyze cephalosporins and carbapenems is especially worrying in a geographic area where OXA-48 is endemic and effective surveillance for antibiotic resistance is largely unaffordable.
Clinical Significance of Low Cytomegalovirus DNA Levels in Human Plasma
Authors: Waggoner Jesse , Ho Dora Y. , Libiran Paolo , Pinsky Benjamin A.
Published: April 2012

The clinical significance of the detection of low copy numbers of cytomegalovirus (CMV) DNA in immune-suppressed patients remains unclear. In this study, we compared the
artus
CMV Rotor-Gene PCR, utilizing an automated nucleic acid extraction and assay setup (the
artus
CMV protocol), with the COBAS Amplicor CMV Monitor test (our reference protocol). We then analyzed the results of all CMV PCR tests ordered following the implementation of the
artus
CMV protocol at our institution and followed 91 adult patients with positive test results. The
artus
CMV protocol had a linear range extending from 2.0 to 7.0 log
10
copies/ml and had a lower limit of 95% detection of 57 copies/ml. With archived plasma samples, this protocol demonstrated 100% sensitivity and 94% specificity for the detection of CMV DNA. Following implementation of the
artus
CMV protocol, 320 of 1,403 (22.8%) plasma samples tested positive (compared with 323/3,579 [9.0%] samples in the preceding 6 months), and 227 (16.2%) samples had copy numbers of <400/ml. Ninety-one adult patients had at least one positive test. The data were analyzed using a threshold of 200 copies/ml, and in 22 episodes, the viral load increased from <200 copies/ml to ≥200 copies/ml on sequential tests. In 21 of these 22 episodes, either the viral load continued to increase or antiviral treatment was initiated in response to the repeat value. In summary, we evaluate the performance characteristics of a protocol utilizing the
artus
CMV PCR and identify clinically meaningful changes in CMV DNA copy numbers even when they are initially detected at a low level.
Raynaud's Phenomenon, Cytokines and Acupuncture: A Case Report
Authors: Omole Folashade S , Lin James S , Chu Tehching , Sow Charles M , Flood Anthony , Powell Michael David
Published: April 2012

A 30-year-old African-American woman diagnosed in 2006 with primary Raynaud's phenomenon (RP) was seen in the clinic in 2010 and the diagnosis confirmed excluding underlying disorders. Acupuncture was administered bilaterally at the LI4 Hegu acupuncture points for 5 min twice weekly for 2 months, which resulted in improvement in pain severity, joint stiffness and the colour of her fingers and toes. The literature reveals that acupuncture is effective in improving pain severity and joint stiffness in RP. The patient's serum proinflammatory cytokines were compared with those from an ongoing study in our institution and the results indicated that acupuncture therapy might be anti-inflammatory. Acupuncture is relatively safe and should be considered as an alternative treatment or non-pharmacological therapy for pain associated with RP.
Inhaled hypertonic saline in adults hospitalised for exacerbation of cystic fibrosis lung disease: a retrospective study
Authors: Pezzulo Alejandro A , Stoltz David A , Hornick Douglas B , Durairaj Lakshmi
Published: April 2012

Background

Inhaled hypertonic saline (HTS) improves quality of life and reduces pulmonary exacerbations when given long term in patients with cystic fibrosis (CF). While increasingly being offered for acute pulmonary exacerbations, little is known about the efficacy in this setting.

Objectives

The authors examined the tolerability and efficacy of HTS use among adult subjects hospitalised with a CF pulmonary exacerbation and hypothesised that use of HTS would improve pulmonary function during the admission.

Design

Pilot retrospective non-randomised study.

Setting

Single tertiary care centre.

Participants

45 subjects admitted to the inpatient service for acute CF pulmonary exacerbation in 2006–2007. A subset of 18 subjects who were also admitted in 2005 when HTS was not available was included in the comparative study.

Primary outcome

Change in forced expiratory volume in one second from admission to discharge.

Secondary outcomes

Change in weight from admission to discharge and time to next exacerbation.

Results

Mean age was 32.5 years, and mean length of stay was 11.5 days. HTS was offered to 33 subjects and was well tolerated for a total use of 336 days out of 364 days of hospital stay. Baseline demographics, lung function and sputum culture results were comparable in first and second visits. Use of HTS was not associated with an improvement in forced expiratory volume in one second (p=0.1), weight gain (p=0.24) or in the time to next admission (p=0.08).

Conclusions

These pilot data suggest that HTS is well tolerated during CF pulmonary exacerbation but offers no clear outcome benefits. It is possible that HTS may not have much advantage above and beyond intensive rehabilitation and intravenous antibiotics and may add to hospital costs and treatment burden.
Knowledge about epilepsy among health professionals: a cross-sectional survey in São Paulo, Brazil
Authors: Vancini Rodrigo Luiz , Benedito-Silva Ana Amélia , Sousa Bolivar Saldanha , Gomes da Silva Sergio , Souza-Vancini Maria Iones , Vancini-Campanharo Cássia Regina , Cabral Francisco Romero , de Lima Cristiano , Barbosa de Lira Claudio Andre
Published: April 2012

Objective

To evaluate the epilepsy knowledge among health professionals in São Paulo, Brazil.

Design

This is a cross-sectional study.

Participants

Professionals with academic degrees in physical education (n=134), nutrition (n=116), medicine (n=100), psychology (n=53), nursing (n=122) and physiotherapy (n=99) who lived in São Paulo City, Brazil.

Primary and secondary outcome measures

Knowledge of health professionals about epilepsy.

Methods

Professionals with academic degrees in physical education (n=134), nutrition (n=116), medicine (n=100), psychology (n=53), nursing (n=122) and physiotherapy (n=99) who lived in São Paulo City, Brazil, were invited to participate in the study. The subjects (n=624) answered a questionnaire composed of 25 simple closed-ended questions from three areas: personal, educational and knowledge.

Results

Out of all subjects, 88.5% (n=552) had a postgraduate education, while 11.5% (n=72) had only an undergraduate degree. The authors found that physical educators, nutritionists and physiotherapists received lower scores on their epilepsy knowledge than other health professionals.

Conclusions

Health professionals are considered better-educated group inside the society, especially with regards to healthcare issues. Thus, it is important they also have an accurate and correct knowledge about epilepsy. The findings of the present study indicate an imperative improvement in education about epilepsy, as well as an inclusion of formal programmes for epilepsy education especially for non-medical professionals. An improvement in epilepsy education might contribute to an improvement in epilepsy care and management.
Current practices for paediatric procedural sedation and analgesia in emergency departments: results of a nationwide survey in Korea
Authors: Seo Jun Seok , Kim Do Kyun , Kang Youngjoon , Kyong Yeon Young , Kim Jin Joo , Ahn Ji Yun , Lee Ji Sook , Jang Hye Young , Jung Jin Hee , Choi Yoon Hee , Han Seung Baik , Lee Jin Hee
Published: April 2012

Objective

Procedural sedation and analgesia (PSA) in children has become a standard tool in emergency settings, but no national PSA guidelines have been developed for the emergency department (ED) in Korea. Therefore, we investigated the practice of PSA and the level of adherence to institutional PSA guidelines in EDs of teaching hospitals.

Methods

This study was a cross-sectional, web-based survey. The study subjects were the faculty of EDs from 96 teaching hospitals. The questionnaire was posted on an internet site, and the participants were requested that the questionnaire be answered by email and telephone in May 2009.

Results

The questionnaires were completed by 67.7% of the participants. Only 20% of EDs had institutional PSA guidelines, 21.5% of those had discharge criteria and 13.8% of EDs had a discharge instruction form. Residents were administered PSA at 76.9% of EDs. The airway rescue equipment was near the area where PSA was performed in 76.9% of EDs. The most commonly used medication for both diagnostic imaging and painful procedure was oral chloral hydrate (87.7%, 61.5%). In 64.6% of EDs, patients were monitored. In only 21 cases, EDs (50.0%) monitored the patients to recovery after PSA or discharge.

Conclusions

Current PSA for paediatric patients have not been appropriately applied in Korea. Unified PSA guidelines were rare in the hospitals surveyed, and many patients were not monitored over an appropriate duration, nor did they receive adequate medications for sedation by the best trained personnel. Therefore, the national PSA guidelines must be developed and implemented as early as possible.
The impact of changing the 4 h emergency access standard on patient waiting times in emergency departments in England
Authors: Woodcock Thomas , Poots Alan J , Bell Derek
Published: April 2012

Objective

To determine whether the process of emergency care waiting in England has changed following the modification of the operational standard for the 4 h waiting time target from 98% to 95% in June 2010.

Design

Retrospective analysis of publicly available ‘total time spent in accident and emergency’ data from Department of Health.

Setting and participants

Patients attending emergency departments (EDs) in England between October 2002 and September 2011. In 2005, the government set an operational standard that 98% of patients should wait <4 h in ED. In June 2010, the government announced that the operating standard would change to 95% immediately.

Outcome measures

Percentage of patients waiting <4 h (weekly and quarterly), and total number of patients waiting >4 h.

Results

The average percentage of patients waiting <4 h fell from 98% to 95% almost immediately following the operational standard change. Consequently, between October 2010 and September 2011, approximately 383 000 additional patients in England EDs waited in excess of 4 h than had the 98% standard been attained. The emergency care system appears to have been stabilised at this new level.

Conclusions

The policy change for waiting times in EDs in England has resulted in the process of emergency care in England adjusting to the new operational standard of 95% of patients waiting <4 h. As a result, more patients are waiting >4 h to receive the care they need; consequently, outcomes are likely to suffer.