bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrating Conjugative Elements as Vectors of Antibiotic, Mercury, and Quaternary Ammonium Compound Resistance in Marine Aquaculture Environments
Authors: Rodríguez-Blanco Arturo , Lemos Manuel L. , Osorio Carlos R.
Published: February 2012

The presence of SXT/R391-related integrating conjugative elements (ICEs) in bacterial strains isolated from fish obtained from marine aquaculture environments in 2001 to 2010 in the northwestern Iberian Peninsula was studied. ICEs were detected in 12 strains taxonomically related to
Vibrio scophthalmi
(3 strains),
Vibrio splendidus
(5 strains),
Vibrio alginolyticus
(1 strain),
Shewanella haliotis
(1 strain), and
Enterovibrio nigricans
(2 strains), broadening the known host range able to harbor SXT/R391-like ICEs. Variable DNA regions, which confer element-specific properties to ICEs of this family, were characterized. One of the ICEs encoded antibiotic resistance functions in variable region III, consisting of a tetracycline resistance locus. Interestingly, hot spot 4 included genes providing resistance to rifampin (ICE
Vsp
Por2 and ICE
Val
Por1) and quaternary ammonium compounds (QACs) (ICE
Eni
Spa1), and variable region IV included a mercury resistance operon (ICE
Vsp
Spa1 and ICE
Eni
Spa1). The S exclusion group was more represented than the R exclusion group, accounting for two-thirds of the total ICEs. Mating experiments allowed ICE mobilization to
Escherichia coli
strains, showing the corresponding transconjugants' rifampin, mercury, and QAC resistance. These results show the first evidence of ICEs providing rifampin and QAC resistances, suggesting that these mobile genetic elements contribute to the dissemination of antimicrobial, heavy metal, and QAC resistance determinants in aquaculture environments.
Expression, Immunogenicity, Histopathology, and Potency of a Mosquito-Based Malaria Transmission-Blocking Recombinant Vaccine
Authors: Mathias D. K. , Plieskatt J. L. , Armistead J. S. , Bethony J. M. , Abdul-Majid K. B. , McMillan A. , Angov E. , Aryee M. J. , Zhan B. , Gillespie P. , Keegan B. , Jariwala A. R. , Rezende W. , Bottazzi M. E. , Scorpio D. G. , Hotez P. J. , Dinglasan R. R.
Published: February 2012

Vaccines have been at the forefront of global research efforts to combat malaria, yet despite several vaccine candidates, this goal has yet to be realized. A potentially effective approach to disrupting the spread of malaria is the use of transmission-blocking vaccines (TBV), which prevent the development of malarial parasites within their mosquito vector, thereby abrogating the cascade of secondary infections in humans. Since malaria is transmitted to human hosts by the bite of an obligate insect vector, mosquito species in the genus
Anopheles
, targeting mosquito midgut antigens that serve as ligands for
Plasmodium
parasites represents a promising approach to breaking the transmission cycle. The midgut-specific anopheline alanyl aminopeptidase N (AnAPN1) is highly conserved across
Anopheles
vectors and is a putative ligand for
Plasmodium
ookinete invasion. We have developed a scalable, high-yield
Escherichia coli
expression and purification platform for the recombinant AnAPN1 TBV antigen and report on its marked vaccine potency and immunogenicity, its capacity for eliciting transmission-blocking antibodies, and its apparent lack of immunization-associated histopathologies in a small-animal model.
Bundle-Forming Pilus Locus of Aeromonas veronii bv. Sobria
Authors: Hadi Nahal , Yang Qin , Barnett Timothy C. , Tabei S. Mohammed B. , Kirov Sylvia M. , Shaw Jonathan G.
Published: February 2012

Little is known about the colonization mechanisms of
Aeromonas
spp. Previous work has suggested that the type IV bundle-forming pilus (Bfp) is an aeromonad intestinal colonization factor. This study provides the first genetic characterization of this structure. To define the role of Bfp in
Aeromonas veronii
bv. Sobria adherence, a 22-kb locus encoding the bundle-forming pilus was isolated; this contained 17 pilus-related genes similar to the mannose-sensitive hemagglutinin (MSHA) of
Vibrio cholerae
. Reverse transcriptase PCR (RT-PCR) demonstrated that the locus had two major transcriptional units,
mshI
to
mshF
and
mshB
to
mshQ
. Transcriptional fusion experiments demonstrated the presence of two strong promoters upstream of
mshI
and
mshB
. The locus encoded four putative prepilin proteins, one of which (MshA) corresponded to the N-terminal sequence of the previously isolated major pilin protein. All the pilin genes were inactivated, mutation of each minor or major pilin gene greatly reduced the bacterium's ability to adhere and form biofilms, and complementation of each mutant in
trans
rescued this phenotype. Mutation of the major pilin MshA and MshB, a minor pilin, resulted in their loss. The position of the
mshH
gene is conserved within a number of bacteria, and we have shown it is not transcriptionally linked to the other
msh
genes; moreover, its mutation did not have a dramatic effect on either adhesion or biofilm formation. We conclude that the bundle-forming pilus is required for
A. veronii
bv. Sobria adherence and biofilm formation; furthermore, both the major and minor pilin proteins are essential for this process.
Strain-Specific Regulatory Role of Eukaryote-Like Serine/Threonine Phosphatase in Pneumococcal Adherence
Authors: Agarwal Shivangi , Agarwal Shivani , Pancholi Preeti , Pancholi Vijay
Published: February 2012

Streptococcus pneumoniae
exploits a battery of virulence factors to colonize the host. Although the eukaryote-like Ser/Thr kinase of
S. pneumoniae
(StkP) has been implicated in physiology and virulence, the role of its cotranscribing phosphatase (PhpP) has remained elusive. The construction of nonpolar markerless
phpP
knockout mutants (Δ
phpP
) in two pathogenic strains, D39 (type 2) and 6A-EF3114 (type 6A), indicated that PhpP is not indispensable for pneumococcal survival. Further, PhpP also participates in the regulation of cell wall biosynthesis/division, adherence, and biofilm formation in a strain-specific manner. Additionally, we provide hitherto-unknown
in vitro
and
in vivo
evidence of a physiologically relevant biochemical link between the StkP/PhpP-mediated cognate regulation and the two-component regulatory system TCS06 (RR06/HK06) that regulates the expression of the gene encoding an important pneumococcal surface adhesin, CbpA, which was found to be significantly upregulated in Δ
phpP
mutants. In particular, StkP (threonine)-phosphorylated RR06 bound to the
cbpA
promoter with high efficiency even in the absence of the HK06-responsive and catalytically active aspartate 51 residue. Together, our findings unravel the significant contributions of PhpP in pneumococcal physiology and adherence.
DksA-Dependent Resistance of Salmonella enterica Serovar Typhimurium against the Antimicrobial Activity of Inducible Nitric Oxide Synthase
Authors: Henard Calvin A. , Vázquez-Torres Andrés
Published: February 2012

In coordination with the ppGpp alarmone, the RNA polymerase regulatory protein DksA controls the stringent response of eubacteria, negatively regulating transcription of translational machinery and directly activating amino acid promoters and
de novo
amino acid biosynthesis. Given the effects of nitric oxide (NO) on amino acid biosynthetic pathways and the intimate relationship of DksA with amino acid synthesis and transport, we tested whether DksA contributes to the resistance of
Salmonella
to reactive nitrogen species (RNS). Our studies show that the zinc finger predicted to position DksA in the secondary channel of the RNA polymerase is essential for the resistance of
Salmonella enterica
serovar Typhimurium to RNS in a murine model of systemic salmonellosis. Despite exhibiting auxotrophies for various amino acids, Δ
dksA
mutant
Salmonella
strains regain virulence in mice lacking inducible NO synthase (iNOS). DksA is also important for growth of this intracellular pathogen in the presence of NO congeners generated by iNOS during the innate response of murine macrophages. Accordingly,
dksA
mutant
Salmonella
strains are hypersusceptible to chemically generated NO, a phenotype that can be prevented by adding amino acids. The DksA-dependent antinitrosative defenses do not rely on the Hmp flavohemoprotein that detoxifies NO to NO
3
−
and appear to operate independently of the ppGpp alarmone. Our investigations are consistent with a model by which NO produced in the innate response to
Salmonella
exerts considerable pressure on amino acid biosynthesis. The cytotoxicity of NO against
Salmonella
amino acid biosynthetic pathways is antagonized in great part by the DksA-dependent regulation of amino acid biosynthesis and transport.
Accuracy of ECG interpretation in competitive athletes: the impact of using standardised ECG criteria
Authors: Drezner Jonathan A , Asif Irfan M , Owens David S , Prutkin Jordan M , Salerno Jack C , Fean Robyn , Rao Ashwin L , Stout Karen , Harmon Kimberly G
Published: February 2012

Background

Interpretation of ECGs in athletes is complicated by physiological changes related to training. The purpose of this study was to determine the accuracy of ECG interpretation in athletes among different physician specialties, with and without use of a standised ECG criteria tool.

Methods

Physicians were asked to interpret 40 ECGs (28 normal ECGs from college athletes randomised with 12 abnormal ECGs from individuals with known ciovascular pathology) and classify each ECG as (1) ‘normal or variant – no further evaluation and testing needed’ or (2) ‘abnormal – further evaluation and testing needed.’ After reading the ECGs, participants received a two-page ECG criteria tool to guide interpretation of the ECGs again.

Results

A total of 60 physicians participated: 22 primary care (PC) residents, 16 PC attending physicians, 12 sports medicine (SM) physicians and 10 ciologists. At baseline, the total number of ECGs correctly interpreted was PC residents 73%, PC attendings 73%, SM physicians 78% and ciologists 85%. With use of the ECG criteria tool, all physician groups significantly improved their accuracy (p<0.0001): PC residents 92%, PC attendings 90%, SM physicians 91% and ciologists 96%. With use of the ECG criteria tool, specificity improved from 70% to 91%, sensitivity improved from 89% to 94% and there was no difference comparing ciologists versus all other physicians (p=0.053).

Conclusions

Providing standised criteria to assist ECG interpretation in athletes significantly improves the ability to accurately distinguish normal from abnormal findings across physician specialties, even in physicians with little or no experience.
Childhood residential mobility and health in late adolescence and adulthood: findings from the West of Scotland Twenty-07 Study
Authors: Brown D , Benzeval M , Gayle V , Macintyre S , O'Reilly D , Leyland A H
Published: February 2012

Background

The relationship between childhood residential mobility and health in the UK is not well established; however, research elsewhere suggests that frequent childhood moves may be associated with poorer health outcomes and behaviours. The aim of this paper was to compare people in the West of Scotland who were residentially stable in childhood with those who had moved in terms of a range of health measures.

Methods

A total of 850 respondents, followed-up for a period of 20 years, were included in this analysis. Childhood residential mobility was derived from the number of addresses lived at between birth and age 18. Multilevel regression was used to investigate the relationship between childhood residential mobility and health in late adolescence (age 18) and adulthood (age 36), accounting for socio-demographic characteristics and frequency of school moves. The authors examined physical health measures, overall health, psychological distress and health behaviours.

Results

Twenty per cent of respondents remained stable during childhood, 59% moved one to two times and 21% moved at least three times. For most health measures (except physical health), there was an increased risk of poor health that remained elevated for frequent movers after adjustment for socio-demographic characteristics and school moves (but was only significant for illegal drug use).

Conclusions

Risk of poor health was elevated in adolescence and adulthood with increased residential mobility in childhood, after adjusting for socio-demographic characteristics and school moves. This was true for overall health, psychological distress and health behaviours, but physical health measures were not associated with childhood mobility.
ANALYTIC REGULARITY FOR LINEAR ELLIPTIC SYSTEMS IN POLYGONS AND POLYHEDRA
Authors: COSTABEL MARTIN , DAUGE MONIQUE , NICAISE SERGE
Published: February 2012

We prove weighted anisotropic analytic estimates for solutions of second-order elliptic boundary value problems in polyhedra. The weighted analytic classes which we use are the same as those introduced by Guo in 1993 in view of establishing exponential convergence for hp finite element methods in polyhedra. We first give a simple proof of the known weighted analytic regularity in a polygon, relying on a new formulation of elliptic a priori estimates in smooth domains with analytic control of derivatives. The technique is based on dyadic partitions near the corners. This technique can successfully be extended to polyhedra, providing isotropic analytic regularity. This is not optimal, because it does not take advantage of the full regularity along the edges. We combine it with a nested open set technique to obtain the desired three-dimensional anisotropic analytic regularity result. Our proofs are global and do not require the analysis of singular functions.
SCHRÖDINGER–LICHNEROWICZ LIKE FORMULA ON KÄHLER–NORDEN MANIFOLDS
Authors: DEĞİRMENCI NEDİM , KARAPAZAR ŞENAY
Published: February 2012

A new kind of spinors and Dirac operator are introduced on Kähler–Norden manifolds in [Spinors on Kähler–Norden manifolds, J. Nonlinear Math. Phys.17(1) (2010) 27–34]. In this work the square D2of the Dirac operator D is computed and a kind of Schrödinger–Lichnerowicz formula is obtained.
Pebbles and Branching Programs for Tree Evaluation
Authors: Cook Stephen , McKenzie Pierre , Wehr Dustin , Braverman Mark , Santhanam Rahul
Published: February 2012

We introduce the
tree evaluation problem
, show that it is in
LogDCFL
(and hence in
P
), and study its branching program complexity in the hope of eventually proving a superlogarithmic space lower bound. The input to the problem is a rooted, balanced
d
-ary tree of height
h
, whose internal nodes are labeled with
d
-ary functions on [
k
] = {1,...,
k
}, and whose leaves are labeled with elements of [
k
]. Each node obtains a value in [
k
] equal to its
d
-ary function applied to the values of its
d
children. The output is the value of the root. We show that the standard black pebbling algorithm applied to the binary tree of height
h
yields a deterministic
k
-way branching program with
O
(
k
h
) states solving this problem, and we prove that this upper bound is tight for
h
 = 2 and
h
 = 3. We introduce a simple semantic restriction called
thrifty
on
k
-way branching programs solving tree evaluation problems and show that the same state bound of
Θ
(
k
h
) is tight for all
h
 ≥ 2 for deterministic thrifty programs. We introduce fractional pebbling for trees and show that this yields nondeterministic thrifty programs with
Θ
(
k
h/2+1
) states solving the Boolean problem “determine whether the root has value 1”, and prove that this bound is tight for
h
 = 2,3,4. We also prove that this same bound is tight for unrestricted nondeterministic
k
-way branching programs solving the Boolean problem for
h
 = 2,3.
Three-Query Locally Decodable Codes with Higher Correctness Require Exponential Length
Authors: Gal Anna , Mills Andrew
Published: February 2012

Locally decodable codes are error-correcting codes with the extra property that, in order to retrieve the value of a single input position, it is sufficient to read a small number of positions of the codeword. We refer to the probability of getting the correct value as the
correctness
of the decoding algorithm.

A breakthrough result by Yekhanin [2007] showed that 3-query linear locally decodable codes may have subexponential length. The construction of Yekhanin, and the three query constructions that followed, achieve correctness only up to a certain limit which is 1 − 3
δ
for nonbinary codes, where an adversary is allowed to corrupt up to
δ
fraction of the codeword. The largest correctness for a subexponential length 3-query binary code is achieved in a construction by Woodruff [2008], and it is below 1 − 3
δ
.

We show that achieving slightly larger correctness (as a function of
δ
) requires exponential codeword length for 3-query codes. Previously, there were no larger than quadratic lower bounds known for locally decodable codes with more than 2 queries, even in the case of 3-query linear codes. Our lower bounds hold for linear codes over arbitrary finite fields and for binary nonlinear codes. Considering larger number of queries, we obtain lower bounds for q-query codes for
q
 > 3, under certain assumptions on the decoding algorithm that have been commonly used in previous constructions. We also prove bounds on the largest correctness achievable by these decoding algorithms, regardless of the length of the code. Our results explain the limitations on correctness in previous constructions using such decoding algorithms. In addition, our results imply trade-offs on the parameters of error-correcting data structures.
Experimental Study of the Freezing Point of γ-Al2O3/Water Nanofluid
Authors: Maré Thierry , Sow Ousmane , Halelfadl Salma , Lebourlout Sylvain , Nguyen Cong Tam
Published: February 2012

Nanofluids are colloidal suspensions made of nanometer-sized particles dispersed in a conventional fluid. Their unusual thermal properties explain intensive investigations for several thermal and industrial applications. In this work, an experimental investigation was performed to measure the freezing point and to study the supercooling point made of alumina γ-Al2O3 nanoparticles with 30 nm diameter size and deionized water. Particles' volume fraction used in this work is ranging from 1% to 4%. The T-historic method based on the measurement of the point of inflexion was performed to measure the thermal properties such as the freezing point and the latent heat of solidification of the nanofluids for different concentrations. The results show that the supercooling degree decreases for the high particles volume concentrations and that the agglomeration does not influence the temperature of the freezing point. However, it makes the freezing process longer.
Primary Cutaneous Melanoma Arising in a Long-Standing Irradiated Keloid
Authors: Fish Lindsay M. , Duncan Lisa , Gray Keith D. , Bell John L. , Lewis James M.
Published: February 2012

Ionizing radiation has been used therapeutically for a variety of clinical conditions, including treatment of hypertrophic keloids. Keloids may rarely be associated with malignancy, but the use of low-dose ionizing radiation is associated with an increased risk of cutaneous malignancies. We describe a case in which a primary desmoplastic melanoma arose in a long-standing, previously irradiated keloid.
M94 as a Unique Testbed for Black Hole Mass Estimates and AGN Activity at Low Luminosities
Authors: Constantin Anca , Seth Anil C.
Published: February 2012

We discuss the peculiar nature of the nucleus of M94 (NGC 4736) in the context of new measurements of the broadHαemission fromHST-STIS observations. We show that this component is unambiguously associated with the high-resolution X-ray, radio, and variable UV sources detected at the optical nucleus of this galaxy. These multiwavelength observations suggest that NGC 4736 is one of the least luminous broad-line (type 1) LINERs, withLbol=2.5×1040 erg s-1. This LINER galaxy has also possibly the least luminous broad-line region known (LHα=2.2×1037 erg s-1). We compare black hole mass estimates of this system to the recently measured∼7×106 M⨀dynamical black hole mass measurement. The fundamental plane andM-σ*relationship roughly agree with the measured black hole mass, while other accretion-based estimates (theM-FWHM(Hα)relation, empirical correlation of BH mass with high-ionization mid-IR emission lines, and the X-ray excess variance) provide much lower estimates (∼105 M⨀). An energy budget test shows that the AGN in this system may be deficient in ionizing radiation relative to the observed emission-line activity. This deficiency may result from source variability or the superposition of multiple sources including supernovae.
Opioid Dependent and Pregnant: What Are the Best Options for Mothers and Neonates?
Authors: Unger Annemarie , Metz Verena , Fischer Gabriele
Published: February 2012

Pregnancy in opioid-dependent women is a major public health issue. Women who are afflicted by opioid addiction are a highly vulnerable group of patients frequently becoming pregnant unplanned and at risk of adverse pregnancy outcomes and peri-natal complications. Opioid agonist maintenance treatment is the best option for the majority of women. Ideally, early and closely monitored treatment in an interdisciplinary team approach including social workers, nurses, psychologists, psychiatrists, gynecologists, anesthesiologists, and pediatricians should be provided. The treatment of comorbid psychiatric conditions, the resolution of financial, legal, and housing issues, and the psychosocial support provided have a significant effect on optimizing pregnancy outcomes. This paper aims to update health professionals in the field of gynecology and obstetrics on the latest optimal treatment approaches for mothers suffering from opioid dependence and their neonates.
Activation of Peroxisome Proliferator-Activated Receptor-Gamma by Glitazones Reduces the Expression and Release of Monocyte Chemoattractant Protein-1 in Human Mesothelial Cells
Authors: Sauter Matthias , Kastenmüller Kathrin , Belling Franziska , Wörnle Markus , Ladurner Roland , Mussack Thomas , Sitter Thomas
Published: February 2012

Human peritoneal mesothelial cells (MC) play an important role in inflammatory processes of the peritoneal cavity by producing various cytokines and chemokines, such as monocyte chemoattractant protein-1 (MCP-1). The present study was designed to assess the effect of the peroxisome proliferator-activated receptor-gamma- (PPARγ-) activator rosiglitazone on the mesothelial MCP-1 expression and release. Primary cultures of MC were obtained from omental tissue. MCP-1 antigen concentrations were measured in the cell supernatant by ELISA and MCP-1 mRNA levels by real-time polymerase chain reaction. The presence of PPARγon MC was assayed in a Western Blot analysis. MC constitutively express PPARγ. Activation of this receptor via rosiglitazone (0,1–10 μmol/L) resulted in significantly reduced amounts of mesothelial MCP-1 release as well as MCP-1 mRNA. The use of the PPARγinhibitor GW-9662 could completely prevent the rosiglitazone effects. Rosiglitazone was also effective in reducing TNFα-induced enhanced secretion of MCP-1. Our findings indicate that glitazones are effective in reducing constitutive and TNFα-stimulated mesothelial MCP-1 mRNA expression and release.
Developing a Fuzzy Logic Based on Demand Multicast Routing Protocol
Authors: Shams Shafigh Alireza , Abdollahi Kamran , Kouchaki Marjan
Published: February 2012

Multicast routing is an efficient method to lead data packets from one source group to several nodes as destination group. Although multicast routing algorithms could be efficient in many situations but their routing mechanism like as route request flooding packets likely results in poor performance in comparison to unicast routing algorithms. In this research, two efficient methods are proposed to improve the performance of On Demand Multicast Routing Protocol (ODMRP). The main proposed method tries to establish a small, efficient, and high‐quality forwarding group. This is achieved by augmenting the Join Query packets with additional information such as speed, power level of node, and link bandwidths. Besides, the control overhead is further reduced by restricting the domain of control packet flooding (by restricting the domain of control packet flooding). The performance evaluation shows that the proposed scheme increases the packet delivery rate by up to 40%, while reducing average end‐to‐end delay and consumed power by about 35% and 45%, respectively.
The Efficacy and Safety of Endoscopic Ultrasound-Guided Celiac Plexus Neurolysis for Treatment of Pain in Patients with Pancreatic Cancer
Authors: Wiechowska-Kozłowska Anna , Boer Klaudiusz , Wójcicki Maciej , Milkiewicz Piotr
Published: February 2012

Introduction.Celiac plexus neurolysis is used in pain management of patients with advanced and unresectable pancreatic cancer. We retrospectively analyzed efficacy and safety of endoscopic ultrasound- (EUS-) guided celiac plexus neurolysis in patients treated in our unit.Methods.Twenty nine subjects with unresectable pancreatic cancer and severe pain despite pharmacological treatment underwent EUS-guided celiac plexus neurolysis with 98% ethanol. Patients scored their pain according to a 0–10 point scale and were interviewed 1-2 weeks and 2-3 months after the procedure.Results.Twenty five (86%) patients reported improvement in their pain at 1-2 weeks following the procedure. Of these, 7 (24%) reported substantial improvement (decrease in pain by more than 50%) and 4 (14%) complete disappearance of pain. Pain relief was still present in 76% of patients after 2-3 months. Treatment-related side effects included hypotonia in 1 patient, severe pain immediately postprocedure in 2 patients, and short episodes of diarrhea in 3 patients.Conclusion.Endoscopic ultrasound- (EUS-) guided celiac plexus neurolysis is a safe and effective treatment of severe pain from advanced pancreatic cancer.
Interference-Free Wakeup Scheduling with Consecutive Constraints in Wireless Sensor Networks
Authors: Ma Junchao , Lou Wei
Published: February 2012

Wakeup scheduling has been widely used in wireless sensor networks (WSNs), for it can reduce the energy wastage caused by the idle listening state. In a traditional wakeup scheduling, sensor nodes start up numerous times in a period, thus consuming extra energy due to state transitions (e.g., from the sleep state to the active state). In this paper, we address a novel interference-free wakeup scheduling problem called compact wakeup scheduling, in which a node needs to wake up only once to communicate bidirectionally with all its neighbors. However, not all communication graphs have valid compact wakeup schedulings, and it is NP-complete to decide whether a valid compact wakeup scheduling exists for an arbitrary graph. In particular, tree and grid topologies, which are commonly used in WSNs, have valid compact wakeup schedulings. We propose polynomial-time algorithms using the optimum number of time slots in a period for trees and grid graphs. Simulations further validate our theoretical results.
On the Solution of Double‐Diffusive Convective Flow due to a Cone by a Linearization Method
Authors: Narayana Mahesha , Sibanda Precious
Published: February 2012

The paper details the use of a nonperturbation successive linearization method to solve the coupled nonlinear boundary value problem due to double‐diffusive convection from an inverted cone. Diffusion‐thermo and thermal‐diffusion effects have been taken into account. The governing partial differential equations are transformed into ordinary differential equations using a suitable similarity transformation. The SLM is based on successively linearizing the governing nonlinear boundary layer equations and solving the resulting higher‐order deformation equations using spectral methods. The results are compared with the limited cases from previous studies and results obtained using the Matlab inbuilt bvp4c numerical algorithm and a shooting technique that uses Runge‐Kutta‐Fehlberg (RKF45) and Newton‐Raphson schemes. These comparisons reveal the robustness and validate the usage of the linearisation method technique. The results show that the nonperturbation technique in combination with the Chebyshev spectral collocation method is an efficient numerical algorithm with assured convergence that serves as an alternative to numerical methods for solving nonlinear boundary value problems.
Postoperative Pain Trajectories in Cardiac Surgery Patients
Authors: Chapman C. Richard , Zaslansky Ruth , Donaldson Gary W. , Shinfeld Amihay
Published: February 2012

Poorly controlled postoperative pain is a longstanding and costly problem in medicine. The purposes of this study were to characterize the acute pain trajectories over the first four postoperative days in 83 cardiac surgery patients with a mixed effects model of linear growth to determine whether statistically significant individual differences exist in these pain trajectories, and to compare the quality of measurement by trajectory with conventional pain measurement practices. The data conformed to a linear model that provided slope (rate of change) as a basis for comparing patients. Slopes varied significantly across patients, indicating that the direction and rate of change in pain during the first four days of recovery from surgery differed systematically across individuals. Of the 83 patients, 24 had decreasing pain after surgery, 24 had increasing pain, and the remaining 35 had approximately constant levels of pain over the four postoperative days.
High‐Level Synthesis: Productivity, Performance, and Software Constraints
Authors: Liang Yun , Rupnow Kyle , Li Yinan , Min Dongbo , Do Minh N. , Chen Deming
Published: February 2012

FPGAs are an attractive platform for applications with high computation demand and low energy consumption requirements. However, design effort for FPGA implementations remains high—often an order of magnitude larger than design effort using high‐level languages. Instead of this time‐consuming process, high‐level synthesis (HLS) tools generate hardware implementations from algorithm descriptions in languages such as C/C++ and SystemC. Such tools reduce design effort: high‐level descriptions are more compact and less error prone. HLS tools promise hardware development abstracted from software designer knowledge of the implementation platform. In this paper, we present an unbiased study of the performance, usability and productivity of HLS using AutoPilot (a state‐of‐the‐art HLS tool). In particular, we first evaluate AutoPilot using the popular embedded benchmark kernels. Then, to evaluate the suitability of HLS on real‐world applications, we perform a case study of stereo matching, an active area of computer vision research that uses techniques also common for image denoising, image retrieval, feature matching, and face recognition. Based on our study, we provide insights on current limitations of mapping general‐purpose software to hardware using HLS and some future directions for HLS tool development. We also offer several guidelines for hardware‐friendly software design. For popular embedded benchmark kernels, the designs produced by HLS achieve 4X to 126X speedup over the software version. The stereo matching algorithms achieve between 3.5X and 67.9X speedup over software (but still less than manual RTL design) with a fivefold reduction in design effort versus manual RTL design.
Epidemiological Profiles of Foreign-Born and US-Born Hispanic Blood Donors in a Major Metropolitan Area in the United States
Authors: James Adelbert B. , Josephson Cassandra D. , Castillejo Marta I. , Schreiber George B. , Roback John D.
Published: February 2012

Background. The explosive growth of Hispanics in the US makes this population a significant and untapped source for blood donation. Methods. A cross-sectional study was performed to evaluate blood donation behaviors and demographics of foreign-born and US-born Hispanic donors between 2006 and 2009 in metropolitan Atlanta, GA, USA. Bivariate analyses and multivariate logistic regression were used to assess factors associated with foreign-born donors. Results. 5,119 foreign-born and 11,841 US-born Hispanics donated blood. Foreign-born Hispanic donors were more likely than US-born donors to be blood group O (57.6% versus 52.0%; P<.001) and more frequent donors (2.2 versus 2.0; P<.001). Cuban-born donors had the highest rates of return donation (63.2%). In contrast, Mexicans, the most prevalent subpopulation among foreign-born Hispanic donors (31.8%), had the lowest rates of return donation (42.0%). Conclusions. The heterogeneity found among Hispanic donors in this study is valuable for the design of recruitment strategies to increase blood donations.
Emergency Department Crowding: Time for Interventions and Policy Evaluations
Authors: Boyle Adrian , Beniuk Kathleen , Higginson Ian , Atkinson Paul
Published: February 2012

This paper summarises the consequences of emergency department crowding. It provides a comparison of the scales used to measure emergency department crowding. We discuss the multiple causes of crowding and present an up-to-date literature review of the interventions that reduce the adverse consequences of crowding. We consider interventions at the level of an individual hospital and a policy level.
Rapid Heterotrophic Ossification with Cryopreserved Poly(ethylene glycol-) Microencapsulated BMP2-Expressing MSCs
Authors: Mumaw Jennifer , Jordan Erin T. , Sonnet Corinne , Olabisi Ronke M. , Olmsted-Davis Elizabeth A. , Davis Alan R. , Peroni John F. , West Jennifer L. , West Franklin , Lu Yangqing , Stice Steven L.
Published: February 2012

Autologous bone grafting is the most effective treatment for long-bone nonunions, but it poses considerable risks to donors, necessitating the development of alternative therapeutics. Poly(ethylene glycol) (PEG) microencapsulation and BMP2 transgene delivery are being developed together to induce rapid bone formation. However, methods to make these treatments available for clinical applications are presently lacking. In this study we used mesenchymal stem cells (MSCs) due to their ease of harvest, replication potential, and immunomodulatory capabilities. MSCs were from sheep and pig due to their appeal as large animal models for bone nonunion. We demonstrated that cryopreservation of these microencapsulated MSCs did not affect their cell viability, adenoviral BMP2 production, or ability to initiate bone formation. Additionally, microspheres showed no appreciable damage from cryopreservation when examined with light and electron microscopy. These results validate the use of cryopreservation in preserving the viability and functionality of PEG-encapsulated BMP2-transduced MSCs.
A Convex Relaxation Bound for Subgraph Isomorphism
Authors: Schellewald Christian
Published: February 2012

In this work a convex relaxation of a subgraph isomorphism problem is proposed, which leads to a new lower bound that can provide a proof that a subgraph isomorphism
between two graphs can not be found. The bound is based on a semidefinite programming relaxation of a combinatorial optimisation formulation for subgraph isomorphism and is explained in detail. We consider subgraph isomorphism problem instances of simple graphs which means that only the structural information of the two graphs is exploited and other information that might be available (e.g., node positions) is ignored. The bound is based on the fact that a subgraph isomorphism always leads to zero as lowest possible optimal objective value in the combinatorial problem formulation. Therefore, for problem instances with a lower bound that is larger than zero this represents a proof that a subgraph isomorphism can not exist. But note that conversely, a negative lower bound does not imply that a subgraph isomorphism must be present and only indicates that a subgraph isomorphism can not be excluded. In addition, the relation of our approach and the reformulation of the largest common subgraph problem into a maximum clique problem is discussed.
Biospecimens and Biorepositories: From Afterthought to Science
Authors: Vaught Jimmie B. , Henderson Marianne K. , Compton Carolyn C.
Published: February 2012

Biospecimens are recognized as critical components of biomedical research, from basic studies to clinical trials and epidemiologic investigations. Biorepositories have existed in various forms for more than 150 years, from early small collections in pathology laboratories to modern automated facilities managing millions of samples. As collaborative science has developed, it has been recognized that biospecimens must be of consistent quality. Recent years have seen a proliferation of best practices and the recognition of the field of “biospecimen science.” The future of this field will depend on the development of more evidence-based practices in both the research and clinical settings. As the field matures, educating a new generation of biospecimen/biobanking scientists will be an important need. Cancer Epidemiol Biomarkers Prev; 21(2); 253–5. ©2012 AACR.
A Phase II Trial of Fixed-Dose Rate Gemcitabine plus Capecitabine in Metastatic/Advanced Biliary Tract Cancer Patients
Authors: Santini Daniele , Virzi Vladimir , Vasile Enrico , Vincenzi Bruno , Catalano Vincenzo , Graziano Francesco , Masi Gianluca , Bronte Giuseppe , Russo Antonio , Falcone Alfredo , Tonini Giuseppe
Published: February 2012

Background: This phase II trial was conducted to determine the activity and safety of the combination of fixed-dose rate (FDR) gemcitabine and capecitabine in metastatic biliary tract cancer (BTC) patients. Methods: Patients with unresectable BTC who had pathologically confirmed adenocarcinoma, no prior chemotherapy, Eastern Cooperative Oncology Group (ECOG) performance status ≤1 and measurable disease were enrolled. Treatment consisted of FDR gemcitabine at 800 mg/m2 on days 1 and 8 every 21 days with capecitabine administered orally b.i.d. in equal doses (650 mg/m2 b.i.d.) for 14 days (28 doses). Results: Between May 2005 and February 2009, 30 patients were enrolled. The median age was 67 years (45–76) and there were 14 males. Thirty patients were evaluable for response and toxicity. A total of 221 cycles were administered (median 7, range 2–16). One patient achieved complete response and 7 patients achieved partial response, giving an overall response rate of 26.7% in the intention-to-treat population. Twelve patients (40.0%) had stable disease. The median progression-free survival was 6.33 months. The median overall survival was 10.8 months. Grade 3/4 neutropenia and thrombocytopenia were noted in 13 and 7% of the patients, respectively. Grade 2/3 nonhematologic toxicities were asthenia (54% of patients), diarrhea (17%), stomatitis (23%) and hand-foot syndrome (7%). There was no treatment-related death. The drugs taken were skipped at least once in 45% of the patients and the dose was reduced in 26% of them. Conclusions: The combination of FDR gemcitabine and capecitabine in this 3-week cycle is safe and seems to have a good activity in advanced biliary cancer.
Mice Lacking Hypertension Candidate Gene ATP2B1 in Vascular Smooth Muscle Cells Show Significant Blood Pressure Elevation
Authors: Kobayashi Yusuke , Hirawa Nobuhito , Tabara Yasuharu , Muraoka Hidenori , Fujita Megumi , Miyazaki Nobuko , Fujiwara Akira , Ichikawa Yasuhiro , Yamamoto Yuichiro , Ichihara Naoaki , Saka Sanae , Wakui Hiromichi , Yoshida Shin-ichiro , Yatsu Keisuke , Toya Yoshiyuki , Yasuda Gen , Kohara Katsuhiko , Kita Yoshikuni , Takei Kohtaro , Goshima Yoshio , Ishikawa Yoshihiro , Ueshima Hirotsugu , Miki Tetsuro , Umemura Satoshi
Published: February 2012

We reported previously that ATP2B1 was one of the genes for hypertension receptivity in a large-scale Japanese population, which has been replicated recently in Europeans and Koreans. ATP2B1 encodes the plasma membrane calcium ATPase isoform 1, which plays a critical role in intracellular calcium homeostasis. In addition, it is suggested that ATP2B1 plays a major role in vascular smooth muscle contraction. Because the ATP2B1 knockout (KO) mouse is embryo-lethal, we generated mice with vascular smooth muscle cell-specific KO of ATP2B1 using the Cre-loxP system to clarify the relationship between ATP2B1 and hypertension. The KO mice expressed significantly lower levels of ATP2B1 mRNA and protein in the aorta compared with control mice. KO mice showed significantly higher systolic blood pressure as measured by tail-cuff method and radiotelemetric method. Similar to ATP2B1, the expression of the Na
+
-Ca
2+
exchanger isoform 1 mRNA was decreased in vascular smooth muscle cells of KO mice. However, ATP2B4 expression was increased in KO mice. The cultured vascular smooth muscle cells of KO mice showed increased intracellular calcium concentration not only in basal condition but also in phenylephrine-stimulated condition. Furthermore, phenylephrine-induced vasoconstriction was significantly increased in vascular rings of the femoral artery of KO mice. These results suggest that ATP2B1 plays important roles in the regulation of blood pressure through alteration of calcium handling and vasoconstriction in vascular smooth muscle cells.
Aldosterone Blunts Tubuloglomerular Feedback by Activating Macula Densa Mineralocorticoid Receptors
Authors: Fu Yiling , Hall John E. , Lu Deyin , Lin Lin , Manning R. Davis , Cheng Liang , Gomez-Sanchez Celso E. , Juncos Luis A. , Liu Ruisheng
Published: February 2012

Chronic aldosterone administration increases glomerular filtration rate, whereas inhibition of mineralocorticoid receptors (MRs) markedly attenuates glomerular hyperfiltration and hypertension associated with primary aldosteronism or obesity. However, the mechanisms by which aldosterone alters glomerular filtration rate regulation are poorly understood. In the present study, we hypothesized that aldosterone suppresses tubuloglomerular feedback (TGF) via activation of macula densa MR. First, we observed the expression of MR in macula densa cells isolated by laser capture microdissection and by immunofluorescence in rat kidneys. Second, to investigate the effects of aldosterone on TGF in vitro, we microdissected the juxtaglomerular apparatus from rabbit kidneys and perfused the afferent arteriole and distal tubule simultaneously. Under control conditions, TGF was 2.8±0.2 μm. In the presence of aldosterone (10
−8
mol/L), TGF was reduced by 50%. The effect of aldosterone to attenuate TGF was blocked by the MR antagonist eplerenone (10
−5
mol/L). Third, to investigate the effect of aldosterone on TGF in vivo, we performed micropuncture, and TGF was determined by maximal changes in stop-flow pressure P
sf
when tubular perfusion rate was increased from 0 to 40 nL/min. Aldosterone (10
−7
mol/L) decreased ΔP
sf
from 10.1±1.4 to 7.7±1.2 mm Hg. In the presence of
l
-NG-monomethyl arginine citrate (10
−3
mol/L), this effect was blocked. We conclude that MRs are expressed in macula densa cells and can be activated by aldosterone, which increases nitric oxide production in the macula densa and blunts the TGF response.
Central Angiotensin Type 1 Receptor Blockade Decreases Cardiac But Not Renal Sympathetic Nerve Activity in Heart Failure
Authors: Ramchandra Rohit , Hood Sally G. , Watson Anna M.D. , Allen Andrew M. , May Clive N.
Published: February 2012

In heart failure (HF), cardiac sympathetic nerve activity (SNA; CSNA) is increased, which has detrimental effects on the heart and promotes arrhythmias and sudden death. There is evidence that the central renin-angiotensin system plays an important role in stimulating renal SNA in HF. Because SNA to individual organs is differentially controlled, we have investigated whether central angiotensin receptor blockade decreases CSNA in HF. We simultaneously recorded CSNA and renal SNA in conscious normal sheep and in sheep with HF induced by rapid ventricular pacing (ejection fraction: <40%). The effect of blockade of central angiotensin type 1 receptors by intracerebroventricular infusion of losartan (1 mg/h for 5 hours) on resting levels and baroreflex control of CSNA and renal SNA were determined. In addition, the levels of angiotensin receptors in central autonomic nuclei were determined using autoradiography. Sheep in HF had a large increase in CSNA (43±2 to 88±3 bursts per 100 heart beats;
P
<0.05) and heart rate, with no effect on renal SNA. In HF, central infusion of losartan for 5 hours significantly reduced the baseline levels of CSNA (to 69±5 bursts per 100 heart beats) and heart rate. Losartan had no effect in normal animals. In HF, angiotensin receptor levels were increased in the paraventricular nucleus and supraoptic nucleus but reduced in the area postrema and nucleus tractus solitarius. In summary, infusion of losartan reduced the elevated levels of CNSA in an ovine model of HF, indicating that central angiotensin receptors play a critical role in stimulating the increased sympathetic activity to the heart.
Gradients of the Intergenerational Transmission of Health in Developing Countries
Authors: Bhalotra Sonia , Rawlings Samantha
Published: February 2012

This paper investigates the sensitivity of the intergenerational transmission of health to changes in the socioeconomic and public health environment into which children are born using individual survey data on 2.24 million children born to 600,000 mothers during the period 1970 to 2000 in 38 developing countries merged by country and cohort with macroeconomic data. We find that children are more likely to bear the penalty exerted by poor maternal health if they are conceived or born in adverse socioeconomic conditions. Equivalently, shocks to the child's birth environment are more damaging of children born to women with weaker health at birth.
The Emergence of a Modern Youth Culture: The Swedish 1930s
Authors: Franzén Mats
Published: February 2012

This study traces the emergence of a modern youth culture in the 1930s in Sweden, thus challenging the view that it was born in the 1950s. Sweden, at that time, was a society at the crossroads; all over culture and society, modernity opposed what was given. The new youth culture is traced through a study offive popular cultural forms-boys' literature, particularly aviation books, girls' literature, sport, and national and US film, with a special focus on music-looking particularly for its patterning in what is called the boundary and intensity dimensions. Thus, it is possible to demonstrate rich cultural resources for a modern youth culture. However, balancing this against still existing socioeconomic restrictions makes the picture more ambiguous. What is found is not a generalized modern youth culture, but its emergence, resonating in interesting ways with the new Folkhem (the People's Home).
Dynamics of a Protected Housing Market: The Case of Switzerland
Authors: Borowiecki Karol Jan
Published: February 2012

This study posits that there may be a strong relationship between the high degree of protectionism of the Swiss housing market and its stability. The article provides an overview of the Swiss housing policies that, it is argued, are highly conservative in the context of an international comparison. The stability of the Swiss housing economy is empirically tested. Based on the time-period from 1990 to 2009, in which two substantial crises occurred, house prices and construction activity are modelled. The emerging results, which are admittedly based on a very short time-series, are nonetheless consistent with previous theoretical and empirical research. Furthermore, the findings indicate that the Swiss housing economy operates in accordance with fundamentals. Based on a tentative approach that measures the occurrence of the crisis with annual indicator variables, no effects of the crises on the Swiss housing market can be detected.