bluuebunny/crossref_metadata_2025 huggingface dataset:
Introduction to the special issue on the 2007 workshop on design, analysis, and simulation of chip multiprocessors (dasCMP'07)
Authors: Jouppi Norman P. , Kumar Rakesh , Tullsen Dean
Published: August 2008

Chip multiprocessor architectures are becoming increasingly attractive as an option to provide high instruction throughput while keeping power and complexity under control. Such architectures have also been shown to have scalability and productivity advantages. Multi-core processors are fast becoming mainstream.
A stream chip-multiprocessor for bioinformatics
Authors: Karanam Ravi Kiran , Ravindran Arun , Mukherjee Arindam
Published: August 2008

Bioinformatics applications such as gene and protein sequence matching algorithms are characterized by the need to process large amounts of data. While uni-processor performance growth is slowing due to an increasing gap between processor and memory speeds and a saturation of processor clock frequencies, Genbank data is doubling every 15 months. With the advent of chip multiprocessor systems, great improvements in processor performance could potentially be achieved by taking advantage of the high interprocessor communication bandwidth and new models of programming. We propose a stream chip multiprocessor micro- architecture customized for bioinformatics applications that takes advantage of the memory bandwidth available in chip multiprocessors by exploiting the data parallelism available in bioinformatics applications. The proposed stream chip multiprocessor micro architecture, on a Xilinx Virtex-5 FPGA with 60 customized MicroBlaze soft processor cores running at 80 MHz with a PCI- bus limited main memory bandwidth of 0.12 GB/s, would achieve a speed-up of 68% for the Smith-Waterman sequence matching algorithm compared to a 2.4 GHz AMD Opteron 250. An extrapolated 60 long stream CMP running at 1 GHz with a memory access rate of 2.7 GB/s would run 41.7 times faster than the 1.2 GHz Sun Niagara processor, 16.5 times faster than the 2.4 GHz AMD Opteron 250 and 12.3 times faster than the 2.4 GHz Intel Xeon processor.
Parallelization, performance analysis, and algorithm consideration of Hough transform on chip multiprocessors
Authors: Li Wenlong , Chen Yen-Kuang
Published: August 2008

This paper presents a parallelization framework for emerging applications on the future chip multiprocessors (CMPs). With the continuing prevalence of CMP and the number of on-die cores increasing steadily for the foreseeable future, one key issue in harnessing the computation power of such a CMP is how to effectively manage and execute many threads at the same time. Hence, we study a parallelization framework, which includes (1) coarse-grain and fine-grain multi-threading, (2) performance analysis, and (3) algorithms changes. In particular, this paper shows how the Hough Transform can be parallelized, as an example.

Starting with a sports soccer analysis workload that heavily uses Hough Transform to detect lines in sports soccer field, we extract the coarse-grain data-level parallelism and examine its scaling performance on an 8-core symmetric multiprocessor machine. After realizing the parallel performance limiting factors, we target to exploit the fine-grain data-level parallelism and evaluate its speedup on the 8-core machine and a simulated 64-core CMP. Due to parallel overhead and demanding memory requirements, this fine-grain parallelization doesn't contribute significant performance improvement. After that, we propose a new Hough Transform, and parallelize it in a fine-grain way. Experimental data shows that the new Hough Transform exposes a significant amount of concurrency and pretty good data locality. On the simulated 64-core CMP, we achieve parallel scaling of 61.7x, enabling real-time Hough Transform.
Servo
Authors: Zea Nicolas , Sartori John , Kumar Rakesh
Published: August 2008

Conventional programming models were designed to be used by expert programmers for programming for large-scale multiprocessors, distributed computational clusters, or specialized parallel machines. These models, therefore, are deemed either too difficult for an "average" programmer (who will be expected to do parallel programming in the many-core world) or too inefficient to use for many-core architectures [3]. Similarly, conventional execution models were designed for performance, not scalability.

To address the challenge of performance scalability for many-core architectures, we introduce Servo, a Service Oriented programming model that decomposes every program into a set of components (each with its own local memory, mutable state, and a program counter) that either request services or deliver services. Servo is characterized by the decoupling of logical communication mapping between program modules (or services) from physical communication mapping between modules. This allows the services to be migrated and replicated during execution. The proposed model also allows the granularity of data parallel operations to be changed dynamically. This allows runtime variation in the locking granularity which in turn enables higher write-parallelism. Finally, the models partition even data into services. This can significantly enhance locality and makes it possible to have superlinear speedups with increasing number of cores.

Our preliminary investigations demonstrate significant performance scalability advantages for Servo.
Towards hybrid last level caches for chip-multiprocessors
Authors: Zhao Li , Iyer Ravi , Upton Mike , Newell Don
Published: August 2008

As CMP platforms are widely adopted, more and more cores are integrated on to the die. To reduce the off-chip memory access, the last level cache is usually organized as a distributed shared cache. In order to avoid hot-spots, cache lines are interleaved across the distributed shared cache slices using a hash function. However, as we increase the number of cores and cache slices in the platform, this also implies that most of data references go to remote cache slices, thereby increasing the access latency significantly. In this paper, we propose a hybrid last level cache, which has some amount of private space and some amount of shared space on each cache slice. For workloads with no sharing, the goal is to provide more hits into the local slice while still keeping the overall miss rate low. For workloads with sufficient sharing, the goal is to allow more sharing in the last-level cache slice. We present hybrid last-level cache design options and study its hit/miss rate behavior for a number of important server applications and multi-programmed workloads. Our simulation results on running multi-programmed workloads based on SPEC CINT2000 as well as multithreaded workloads based on commercial server benchmarks (TPCC, SPECjbb, SAP and TPCE) show that this architecture is advantageous especially since it can improve the local hit rate significantly while keeping the overall miss rate similar to the shared cache.
Effects of Variations in Nonlinear Damping Coefficients on the Parametric Vibration of a Cantilever Beam with a Lumped Mass
Authors: Silva Demian G. , Varoto Paulo S.
Published: August 2008

Uncertainties in damping estimates can significantly affect the dynamic response
of a given flexible structure. A common practice in linear structural
dynamics is to consider a linear viscous damping model as the major energy
dissipation mechanism. However, it is well known that different forms of
energy dissipation can affect the structure′s dynamic response. The major
goal of this paper is to address the effects of the turbulent frictional damping
force, also known as drag force on the dynamic behavior of a typical flexible
structure composed of a slender cantilever beam carrying a lumped‐mass
on the tip. First, the system′s analytical equation is obtained and solved by
employing a perturbation technique. The solution process considers variations
of the drag force coefficient and its effects on the system′s response.
Then, experimental results are presented to demonstrate the effects of the
nonlinear quadratic damping due to the turbulent frictional force on the system′s
dynamic response. In particular, the effects of the quadratic damping
on the frequency‐response and amplitude‐response curves are investigated.
Numerically simulated as well as experimental results indicate that variations
on the drag force coefficient significantly alter the dynamics of the
structure under investigation.
Synthesis and Characterization of Neodymium Oxide in Silica Matrix by Solgel Protocol Method
Authors: Duhan Surender , Aghamkar Paveen , Singh M.
Published: August 2008

Formation of nanocrystalline rare earth was prepared by solgel route, using tetra‐ethoxysilane and Nd as precursor materials and HCl as a catalyst. The prepared samples were submitted to thermal treatments at temperature 500∘C (5 hours) and 800∘C (10 hours). Structural changes were investigated by XRD, FTIR spectroscopy, and SEM. At 800∘C (10 hours) resulted in the formation of cubic Nd2O3 nanocrystallites with average size ∼ 20 nm.
Norm Attaining Multilinear Forms on L1(μ)
Authors: Saleh Yousef
Published: August 2008

Given an arbitrary measure μ, this study shows that the set of norm attaining multilinear
forms is not dense in the space of all continuous multilinear forms on L1(μ). However, we have the density if and only if μ is purely atomic. Furthermore, the study presents an example of a
Banach space X in which the set of norm attaining operators from X into X∗ is dense in the
space of all bounded linear operators L(X, X∗). In contrast, the set of norm attaining bilinear
forms on X is not dense in the space of continuous bilinear forms on X.
Validation of Alternating Kernel Mixture Method: Application to Tissue Segmentation of Cortical and Subcortical Structures
Authors: Lee Nayoung A. , Priebe Carey E. , Miller Michael I. , Ratnanather J. Tilak
Published: August 2008

This paper describes the application of the alternating Kernel mixture (AKM) segmentation algorithm to high resolution MRI subvolumes acquired from a 1.5T scanner (hippocampus, n = 10 and prefrontal cortex, n = 9) and a 3T scanner (hippocampus, n = 10 and occipital lobe, n = 10). Segmentation of the subvolumes into cerebrospinal fluid, gray matter, and white matter tissue is validated by comparison with manual segmentation. When compared with other segmentation methods that use traditional Bayesian segmentation, AKM yields smaller errors (P < .005, exact Wilcoxon signed rank test) demonstrating the robustness and wide applicability of AKM across different structures. By generating multiple mixtures for each tissue compartment, AKM mimics the increased variation of manual segmentation in partial volumes due to the highly folded tissues. AKM′s superior performance makes it useful for tissue segmentation of subcortical and cortical structures in large‐scale neuroimaging studies.
Parametric and Nonparametric EEG Analysis for the Evaluation of EEG Activity in Young Children with Controlled Epilepsy
Authors: Sakkalis Vangelis , Cassar Tracey , Zervakis Michalis , Camilleri Kenneth P. , Fabri Simon G. , Bigan Cristin , Karakonstantaki Eleni , Micheloyannis Sifis
Published: August 2008

There is an important evidence of differences in the EEG frequency spectrum of control subjects as compared to epileptic subjects. In particular, the study of children presents difficulties due to the early stages of brain development and the various forms of epilepsy indications. In this study, we consider children that developed epileptic crises in the past but without any other clinical, psychological, or visible neurophysiological findings. The aim of the paper is to develop reliable techniques for testing if such controlled epilepsy induces related spectral differences in the EEG. Spectral features extracted by using nonparametric, signal representation techniques (Fourier and wavelet transform) and a parametric, signal modeling technique (ARMA) are compared and their effect on the classification of the two groups is analyzed. The subjects performed two different tasks: a control (rest) task and a relatively difficult math task. The results show that spectral features extracted by modeling the EEG signals recorded from individual channels by an ARMA model give a higher discrimination between the two subject groups for the control task, where classification scores of up to 100% were obtained with a linear discriminant classifier.
A Possible Link between Infection with Burkholderia Bacteria and Systemic Lupus Erythematosus Based on Epitope Mimicry
Authors: Zhang Wei , Reichlin Morris
Published: August 2008

We previously demonstrated that purified polyclonal and monoclonal anti-dsDNA antibodies bind a 15-mer peptide ASPVTARVLWKASHV in ELISA and Dot blot. This 15-mer peptide partial sequence ARVLWKASH shares similarity with burkholderia bacterial cytochrome B 561 partial sequence ARVLWRATH. In this study, we show that purified anti-dsDNA antibodies react with burkholderia fungorum bacterial cell lysates in Western blot. We used anti-dsDNA antibodies to make an anti-dsDNA antibodies affinity column and used this column to purify the burkholderia fungorum bacterial protein. Purified anti-dsDNA antibodies bind specifically to purified bacterial antigen and purified bacterial antigen blocked the anti-dsDNA antibodies binding to dsDNA antigen. Sera with anti-dsDNA antibodies bind specifically to purified bacterial antigen. We obtained protein partial sequence of RAGTDEGFG which is shared with burkholderia bacterial transcription regulator protein sequence. Sera with anti-dsDNA antibodies bind to RAGTDEGFG peptide better than control groups. These data support our hypothesis that the origin of anti-dsDNA antibodies in SLE may be associated with burkholderia bacterial infection.
High Efficiency and Broadband Microstrip Leaky-Wave Antenna
Authors: Losito Onofrio
Published: August 2008

A novel layout of leaky-wave antennas based on tapered design has been proposed and investigated. The new tapered leaky-wave antenna (LWA) was designed running a simple procedure which uses an FDTD code, and using a suitable metal walls down the centerline along the length of the antenna connecting the conductor strip and the ground plane, which allows to use only half of the structure, the adoption of a simple feeding, and the reduction of sidelobes. The good performance of this new tapered microstrip LWA, with reference to conventional uniform microstrip LWAs, is mainly the wider band of 33% for VSWR<2, higher gain (12 dBi), and higher efficiency (up to 85%). Furthermore, from the theoretical analysis we can see that, decreasing the relative dielectric constant of the substrate, the bandwidth of the leaky-wave antenna becomes much wider, improving its performance.
Mitral Leaflet Adaptation to Ventricular Remodeling
Authors: Chaput Miguel , Handschumacher Mark D. , Tournoux Francois , Hua Lanqi , Guerrero J. Luis , Vlahakes Gus J. , Levine Robert A.
Published: August 2008

Background—

Functional mitral regurgitation (MR) is caused by systolic traction on the mitral leaflets related to ventricular distortion. Little is known about whether chronic tethering causes the mitral leaflet area to adapt to the geometric needs imposed by tethering, in part because of inability to reconstruct leaflet area in vivo. Our aim was to explore whether adaptive increases in leaflet area occur in patients with functional MR compared with normal subjects and to test the hypothesis that leaflet area influences MR severity.

Methods and Results—

A new method for 3-dimensional echocardiographic measurement of mitral leaflet area was developed and validated in vivo against 15 sheep heart valves, later excised. This method was then applied in 80 consecutive patients from 3 groups: patients with normal hearts by echocardiography (n=20), patients with functional MR caused by isolated inferior wall-motion abnormality or dilated cardiomyopathy (n=29), and patients with inferior wall-motion abnormality or dilated cardiomyopathy but no MR (n=31). Leaflet area was increased by 35±20% in patients with LV dysfunction compared with normal subjects. The ratio of leaflet to annular area was 1.95±0.40 and was not different among groups, which indicates a surplus leaflet area that adapts to left-heart changes. In contrast, the ratio of total leaflet area to the area required to close the orifice in midsystole was decreased in patients with functional MR compared with those with normal hearts (1.29±0.15 versus 1.78±0.39,
P
=0.001) and compared with patients with inferior wall-motion abnormality or dilated cardiomyopathy but no MR (1.81±0.38,
P
=0.001). After adjustment for measures of LV remodeling and tethering, a leaflet-to-closure area ratio <1.7 was associated with significant MR (odds ratio 23.2, 95% confidence interval 2.0 to 49.1,
P
=0.02).

Conclusions—

Mitral leaflet area increases in response to chronic tethering in patients with inferior wall-motion abnormality and dilated cardiomyopathy, but the development of significant MR is associated with insufficient leaflet area relative to that demanded by tethering geometry. The varying adequacy of leaflet adaptation may explain in part the heterogeneity of this disease among patients. The results suggest the need to understand the mechanisms that underlie leaflet adaptation and whether leaflet area can potentially be modified as part of the therapeutic approach.
Olmesartan Prevents Cardiovascular Injury and Hepatic Steatosis in Obesity and Diabetes, Accompanied by Apoptosis Signal Regulating Kinase-1 Inhibition
Authors: Yamamoto Eiichiro , Dong Yi-Fei , Kataoka Keiichiro , Yamashita Takuro , Tokutomi Yoshiko , Matsuba Shinji , Ichijo Hidenori , Ogawa Hisao , Kim-Mitsuyama Shokei
Published: August 2008

Dietary obesity is associated with type 2 diabetes and cardiovascular diseases, although the underlying mechanism is unknown. This study was undertaken to elucidate the role of angiotensin II and apoptosis signal regulating kinase-1 (ASK1) in obesity/diabetes-associated cardiovascular complications and hepatic steatosis. Mice fed a high-fat diet were treated with olmesartan, an angiotensin II type 1 receptor blocker, to elucidate the role of angiotensin II in diabetic mice. Treatment of mice fed a high-fat diet with olmesartan markedly suppressed cardiac inflammation and fibrosis, as well as vascular endothelial dysfunction and remodeling, induced by obesity/diabetes. Moreover, olmesartan suppressed the disruption of the vascular endothelial NO synthase dimer in diabetic mice. Olmesartan also significantly prevented hepatic steatosis and fibrosis in diabetic mice. These beneficial effects of olmesartan on diabetic mice were associated with the attenuation of ASK1 activation in these mice. ASK1-deficient mice and wild-type mice were compared, regarding the effects of a high-fat diet. A comparison between ASK1-deficient and wild-type mice showed that ASK1 deficiency attenuated cardiac inflammation and fibrosis, as well as vascular endothelial dysfunction and remodeling induced by obesity/diabetes. The amelioration of vascular endothelial impairment by ASK1 deficiency was attributed to the prevention of endothelial NO synthase dimer disruption. ASK1 deficiency also significantly lessened hepatic steatosis in diabetic mice. In conclusion, our work provided the evidence that ASK1 is significantly activated in diet-induced diabetic mice and contributes to cardiovascular diseases and hepatic steatosis in diabetic mice. Moreover, the beneficial effects of angiotensin II inhibition on dietary diabetic mice seem to be mediated by the inhibition of ASK1 activation.
The Effectiveness of Policies and Programs That Attempt to Reduce Firearm Violence
Authors: Makarios Matthew D. , Pratt Travis C.
Published: August 2008

In response to rising rates of firearms violence that peaked in the mid-1990s, a wide range of policy interventions have been developed in an attempt to reduce violent crimes committed with firearms. Although some of these approaches appear to be effective at reducing gun violence, methodological variations make comparing effects across program evaluations difficult. Accordingly, in this article, the authors use meta-analytic techniques to determine what works in reducing gun violence. The results indicate that comprehensive community-based law enforcement initiatives have performed the best at reducing gun violence.
Psychosocial Variables in the Determination of the Verdict Object in Trials for Environmental Crimes in Spain
Authors: Álvarez Pedro , De la Fuente Emilia I. , García Juan , De la Fuente Leticia
Published: August 2008

Every year, 45,000 forest fires occur in Europe, destroying a forested surface area equivalent to the size of Belgium. Nearly 60% of the forest fires have been ascribed to arson, and for this reason the so-called environmental crime has been included in the legal codes of the members of the European Union. For instance, in Spain forest fires are objects of prosecution in a court of law. This study analyzes the following variables: conservatism, dogmatism, locus of control, attitude toward the legal system, factors from the short Neuroticism Extraversion Openness Inventory (responsibility, openness, extraversion, and kindness), specific variables in the particular cases proposed (forest fires), and attitude toward the protection and improvement of the environment. The specific variables used in each case may help in better delineating verdict trends.
Validation and Application of Electronic Propinquity Theory to Computer-Mediated Communication in Groups
Authors: Walther Joseph B. , Bazarova Natalya N.
Published: August 2008

This research presents an experiment based on the theory of electronic propinquity, testing how the presence of alternate communication media, media bandwidth, information complexity, and users' communication skills affect propinquity (the psychological feeling of nearness) and satisfaction that communicators experience using different communication channels. Groups communicated using one or two of several different channels, including face-to-face, desktop video, audio, and text-based chat, with channel differences between members in some groups. Predicted effects of bandwidth, information complexity, communication skills, and comparative media availability on propinquity and satisfaction were observed. These findings demonstrate a confound in previous research on propinquity theory, suggest newfound validity, and extend the model to interactive computer-mediated communication channels unanticipated by the original theory. Implications include the potential of electronic propinquity to account for discrepancies in the research on computer-mediated communication that have been generated by other theories.
Nonresident Father Involvement, Social Class, and Adolescent Weight
Authors: Menning Chadwick L. , Stewart Susan D.
Published: August 2008

Body weight issues disproportionately affect children with nonresident fathers. Using data from the National Longitudinal Study of Adolescent Health, the authors investigate the relationship between nonresident father involvement and adolescent weight, specifically adolescents' risk of being underweight, overweight, and obese. The results show that nonresident father involvement is associated with adolescent weight and that the effect varies according to social class, fathers' obesity, and the gender of the child. Among both males and females, greater involvement with fathers increases their risk of obesity. Among females, the effect of father involvement on obesity is even greater if her father is obese. Among males, greater father involvement is also associated with lower risk of underweight. The effect of father involvement on adolescent obesity also varies by social class: Involvement with a more highly educated nonresident father is associated with a lower risk of obesity. Child support payments are not associated with being at risk of overweight or underweight among males or females. These results suggest that nonresident fathers must be included in policy discussions of adolescent weight, especially given the positive association between nonresident father involvement and adolescent obesity.
Comment on:  Clinical Efficacy and Safety of Parenteral Nutrition in Adolescent Girls With Anorexia Nervosa
Authors: Smith Amber L.
Published: August 2008

Purpose: Anorexia nervosa (AN) is a common chronic disorder characterized by severe malnutrition and psychological disturbances. Parenteral nutrition (PN) is not usually used in nutritional rehabilitation of AN. The aim of this study was to retrospectively evaluate the indications, clinical efficacy, and safety of PN as assessed by short‐ and long‐term outcomes in AN inpatient girls. Methods: During the past 10 years, a total of 198 inpatients were included in this study: 104 (53%) received oral and parenteral refeeding (group A) and 94 (47%) received oral refeeding alone (group B). For each nutritional treatment, clinical efficacy was evaluated by short‐ and long‐term outcomes, and safety was assessed by complication rate. Results: Short‐term outcome assessment indicated weekly weight gain and maximum caloric intake to be higher in PN‐treated patients. Long‐term outcome evaluation showed rehospitalization and recovery rate to be similar in the 2 groups but failure of first nutritional rehabilitation requiring PN significantly greater in group B (17.5%) than in group A (3%) (P < .01). The number of complications was significantly higher in group A than in group B (P < .004), although all complications resolved. Conclusion: Among all nutritional rehabilitation strategies, PN offers an alternative and safe way to successfully treat AN patients. Presence of clinical complications and reduced compliance with individual, group, and family therapy seem to be the main indications for PN, as it promptly improves nutritional status. At pediatric and adolescent ages, psychological disturbances can also contraindicate the use of enteral nutrition, and therefore represent an additional indication for PN.
Effect of Parenteral Serum Plant Sterols on Liver Enzymes and Cholesterol Metabolism in a Patient With Short Bowel Syndrome
Authors: Hallikainen Maarit , Huikko Laura , Kontra Kirsi , Nissinen Markku , Piironen Vieno , Miettinen Tatu , Gylling Helena
Published: August 2008

Hepatobiliary complications are common during parenteral nutrition. Lipid moiety in commercially available solutions contains plant sterols. It is not known whether plant sterols in parenteral nutrition interfere with hepatic function in adults. We detected how different amounts of plant sterols in parenteral nutrition solution affected serum plant sterol concentrations and liver enzymes during a 1.5‐year follow‐up in a patient with short bowel syndrome. Serum lipid, plant sterol, and liver enzyme levels were measured regularly during the transition from Intralipid (100% soy‐based intravenous fat emulsion) to ClinOleic (an olive oil–based intravenous fat emulsion with 80% olive oil, 20% soy oil and lower plant sterols); the lipid supply was also gradually increased from 20 to 35 g/d. Plant sterols in parenteral nutrition solution and serum were measured with gas‐liquid chromatography. During infusion of soy‐based intravenous fat emulsion (30 g/d, total plant sterols 87 mg/d), the concentrations of sitosterol, campesterol, and stigmasterol were 4361, 1387, and 378 μg/dL, respectively, and serum liver enzyme values were ≥ 2.5 times above upper limit of normal. After changing to olive oil–based intravenous fat emulsion (20‐35 g/d, plant sterols 37‐65 mg/d), concentrations decreased to 2148 to 2251 μg/dL for sitosterol, 569‐297 μg/dL for campesterol, and 95‐55 μg/dL for stigmasterol. Concomitantly, liver enzyme values decreased to 1.4 to 1.8 times above upper limit of normal at the end of follow‐up. The nutrition status of the patient improved. The amount of plant sterols in lipid emulsion affects serum liver enzyme levels more than the amount of lipid.
Bedside Nutrition Assessment Past, Present, and Future: A Review of the Subjective Global Assessment
Authors: Keith Jeanette N.
Published: August 2008

Bedside nutrition assessment remains an essential skill for the practicing clinician to master as the nutrition status of our patients directly influences clinical outcomes and mortality rates. Dr Charles E. Butterworth Jr's initial report of malnutrition in hospitalized patients, the so‐called“ skeleton in the closet,” riveted the medical community. Two other studies in the 1970s published prevalence rates of hospital malnutrition of 48% in adult medical patients and 50% in adult surgical patients. Even more disturbing, 75% of patients at risk for malnutrition on admission had worsening nutrition parameters during their hospitalization. These findings led to a search to find an integrated bedside nutrition assessment tool to identify malnutrition in hospitalized patients. Initially reported in 1982, The Subjective Global Assessment is an integrated tool that utilizes the clinical judgment of a practitioner to identify patients at risk of or with malnutrition. It is a clinically useful tool that can be applied at the bedside by the average practitioner. It is a simple, safe, and inexpensive tool allowing for widespread use by trained clinicians and remains the gold standard for new bedside assessment tools.
The Determinants of the Decision To Use Financial Derivatives in the Lodging Industry
Authors: Singh Amrik , Upneja Arun
Published: August 2008

This study investigates the determinants of the decision to hedge in a sample of lodging firms over a 5-year period from 2000 to 2004. Using a probit model, the results show that underinvestment costs, financial distress costs, managerial risk aversion, information asymmetry, cash-flow volatility, proportion of floating-rate debt, foreign sales ratio, and firm size are significant determinants of the decision to hedge. The findings also document that lodging firms predominantly use interest rate swaps and options to manage interest rate risk. These findings are generally consistent with the theory of hedging as well as with prior research findings on the decision to hedge.
The South American Theft Groups
Authors: Caputo Dean A.
Published: August 2008

The South American Theft Groups (SATG) has developed into a transnational criminal network with profound effects on society—from individual victims, to entire industries and local economies. Primarily from Colombia, they continue to frustrate law enforcement with their skills in conducting crimes and eluding adjudication. Of further concern is the escalation of their violent attacks. A historical brief on Colombia and the exploitation of the documented intelligence of the SATG heretofore shed light on the manifestation of this criminal network. Furthermore, nexus between the SATG, paramilitaries, and narcotraffickers are asserted. Finally, exposure of their vulnerabilities is presented (the greatest of which is that most of the members are illegal aliens), and reasonable recommendations are offered for the deterrence of their future successes.
An Examination of NBA MVP Voting Behavior
Authors: Coleman B. Jay , DuMond J. Michael , Lynch Allen K.
Published: August 2008

The selection process of the most valuable player (MVP) in the National Basketball Association (NBA) was recently questioned as to whether African American players were treated unfairly based on their race. Using NBA voting data from the 1995-2005 seasons, two empirical models are developed to examine the role that a player's race plays in the determination of this award. The estimates imply that after controlling for player, team, and market characteristics, there is no statistically significant effect of race on the likelihood that a player will appear on an MVP ballot or on the number of votes he will receive.
Altered expression of cell cycle and apoptotic proteins in chronic hepatitis C virus infection
Authors: Sarfraz Saira , Hamid Saeed , Siddiqui Anwar , Hussain Snawar , Pervez Shahid , Alexander Graeme
Published: August 2008

Background

A disrupted cell cycle progression of hepatocytes was reported in chronic hepatitis C virus (HCV) infection, which can contribute significantly in the associated pathogenesis. The present study aimed to further elaborate these disruptions by evaluating the expression of key cell cycle and apoptotic proteins in chronic HCV infection with particular reference to genotype 3. Archival liver biopsy specimens of chronic HCV-infection (n = 46) and normal histology (n = 5) were analyzed by immunohistochemistry using antibodies against proliferation marker Mcm-2, G1 phase marker Cyclin D1, S phase marker Cyclin A, cell cycle regulators p21 (CDK inhibitor) and p53 (tumor suppressor protein), apoptotic protein Caspase-3 and anti-apoptotic protein Bcl-2.

Results

Elevated Mcm-2 expression was observed in hepatocytes in chronic HCV infection, indicating increased cell cycle entry. Cyclin D1 expression was higher than cyclin A, which suggests a slow progression through the G1 phase. Expression of cell cycle regulators p21 and p53 was elevated, with no concordance between their expressions. The Mcm-2 and p21 expressions were associated with the fibrosis stage (p = 0.0001 and 0.001 respectively) and that of p53 with the inflammation grade (p = 0.051). Apoptotic marker, Caspase-3, was mostly confined to sinusoidal lining cells with little expression in hepatocytes. Anti-apoptotic protein, Bcl-2, was negligible in hepatocytes and detected principally in infiltrating lymphocytes. Expression of all these proteins was unrelated to the HCV genotype and were detected only rarely in the hepatocytes of normal liver.

Conclusion

The results showed an arrested cell cycle state in the hepatocytes of chronic HCV infection, regardless of any association with genotype 3. Cell cycle arrest is characterized by an increased expression of p21, in relation to fibrosis, and of p53 in relation to inflammation. Furthermore, expression of p21 was independent of the p53 expression and coincided with the reduced expression of apoptotic protein Caspase-3 in hepatocytes. The altered expression of these cell cycle proteins in hepatocytes is suggestive of an impaired cell cycle progression that could limit the regenerative response of the liver to ongoing injury, leading to the progression of disease.
Neurophysiological correlates of linearization in language production
Authors: Habets Boukje , Jansma Bernadette M , Münte Thomas F
Published: August 2008

Background

During speech production the planning of a description of several events requires, among other things, a verbal sequencing of these events. During this process, referred to as linearization during conceptualization, the speaker can choose between different types of temporal connectives such as 'Before' X did A, Y did B' or 'After' Y did B, X did A'. To capture the neural events of such linearization processes, event-related potentials (ERP) were measured in native speakers of German. Utterances were elicited by presenting a sequence of two pictures on a video screen. Each picture consists of an object that is associated with a particular action (e.g. book = reading). A coloured vocalization cue indicated to describe the sequence of two actions associated with the objects in chronological (e.g. red cue: 'After' I drove the car, I read a book) or reversed order (yellow cue).

Results

Brain potentials showed reliable differences between the two conditions from 180 ms after the onset of the vocalization prompt, with ERPs from the 'After' condition being more negative. This 'Before/After' difference showed a fronto-central distribution between 180 and 230 ms. From 300 ms onwards, a parietal distribution was observed. The latter effect is interpreted as an instance of the P300 response, which is known to be modulated by task difficulty.

Conclusion

ERPs preceding overt sentence production are sensitive to conceptual linearization. The observed early, more fronto-centrally distributed variation could be interpreted as involvement of working memory needed to order the events according to the instruction. The later parietal distributed variation relates to the complexity in linearization, with the non-chronological order being more demanding during the updating of the concepts in working memory.
APOBEC3G-UBA2 fusion as a potential strategy for stable expression of APOBEC3G and inhibition of HIV-1 replication
Authors: Li Lin , Liang Dong , Li Jing-yun , Zhao Richard Y
Published: August 2008

Background

Although APOBEC3G protein is a potent and innate anti-HIV-1 cellular factor, HIV-1 Vif counteracts the effect of APOBEC3G by promoting its degradation through proteasome-mediated proteolysis. Thus, any means that could prevent APOBEC3G degradation could potentially enhance its anti-viral effect. The UBA2 domain has been identified as an intrinsic stabilization signal that protects protein from proteasomal degradation. In this pilot study, we tested whether APOBEC3G, when it is fused with UBA2, can resist Vif-mediated proteasomal degradation and further inhibit HIV-1 infection.

Results

APOBEC3G-UBA2 fusion protein is indeed more resistant to Vif-mediated degradation than APOBEC3G. The ability of UBA2 domain to stabilize APOBEC3G was diminished when polyubiquitin was over-expressed and the APOBEC3G-UBA2 fusion protein was found to bind less polyubiquitin than APOBEC3G, suggesting that UBA2 stabilizes APOBEC3G by preventing ubiquitin chain elongation and proteasome-mediated proteolysis. Consistently, treatment of cells with a proteasome inhibitor MG132 alleviated protein degradation of APOBEC3G and APOBEC3G-UBA2 fusion proteins. Analysis of the effect of APOBEC3G-UBA2 fusion protein on viral infectivity indicated that infection of virus packaged from HEK293 cells expressing APOBEC3G-UBA2 fusion protein is significantly lower than those packaged from HEK293 cells over-producing APOBEC3G or APOBEC3G-UBA2 mutant fusion proteins.

Conclusion

Fusion of UBA2 to APOBEC3G can make it more difficult to be degraded by proteasome. Thus, UBA2 could potentially be used to antagonize Vif-mediated APOBEC3G degradation by preventing polyubiquitination. The stabilized APOBEC3G-UBA2 fusion protein gives stronger inhibitory effect on viral infectivity than APOBEC3G without UBA2.
Correlating novel variable and conserved motifs in the Hemagglutinin protein with significant biological functions
Authors: Gendoo Deena MA , El-Hefnawi Mahmoud M , Werner Mark , Siam Rania
Published: August 2008

Background

Variations in the influenza Hemagglutinin protein contributes to antigenic drift resulting in decreased efficiency of seasonal influenza vaccines and escape from host immune response. We performed an in silico study to determine characteristics of novel variable and conserved motifs in the Hemagglutinin protein from previously reported H3N2 strains isolated from Hong Kong from 1968–1999 to predict viral motifs involved in significant biological functions.

Results

14 MEME blocks were generated and comparative analysis of the MEME blocks identified blocks 1, 2, 3 and 7 to correlate with several biological functions. Analysis of the different Hemagglutinin sequences elucidated that the single block 7 has the highest frequency of amino acid substitution and the highest number of co-mutating pairs. MEME 2 showed intermediate variability and MEME 1 was the most conserved. Interestingly, MEME blocks 2 and 7 had the highest incidence of potential post-translational modifications sites including phosphorylation sites, ASN glycosylation motifs and N-myristylation sites. Similarly, these 2 blocks overlap with previously identified antigenic sites and receptor binding sites.

Conclusion

Our study identifies motifs in the Hemagglutinin protein with different amino acid substitution frequencies over a 31 years period, and derives relevant functional characteristics by correlation of these motifs with potential post-translational modifications sites, antigenic and receptor binding sites.
The breastfeeding experience of women with major difficulties who use the services of a breastfeeding clinic: a descriptive study
Authors: Lamontagne Caroline , Hamelin Anne-Marie , St-Pierre Monik
Published: August 2008

Background

Many women experience breastfeeding difficulties. Sometimes these difficulties lead to breastfeeding cessation. Breastfeeding clinics provide support for women facing such problems. This study aims to describe the breastfeeding experience of women, particularly those who use the services of the breastfeeding clinic located in the Greater Quebec City area.

Methods

This is a descriptive study based on information gathered through telephone questionnaires that were administered in 2006 to a sample of 86 women and semi-structured interviews conducted with 12 of these women.

Results

Painful nipples/breasts, low milk supply and latching difficulties were the three most frequent major breastfeeding problems identified by women. Their personal characteristics as well as the moral and physical support provided by family and friends and by health professional and clinicians at the breastfeeding clinic were the factors identified most often as having a positive influence on the breastfeeding experience.

Conclusion

The results suggest that breastfeeding clinics have a critical role to play in improving the breastfeeding experience of women with major difficulties.
Recent advances in the compound-oriented and pattern-oriented approaches to the quality control of herbal medicines
Authors: Zeng Zhongda , Chau Foo-tim , Chan Hoi-yan , Cheung Chui-yee , Lau Tsui-yan , Wei Shuiyin , Mok Daniel Kam-wah , Chan Chi-on , Liang Yizeng
Published: August 2008

The current approaches to the quality control of herbal medicines are either compound-oriented or pattern-oriented, the former targeting specific components with some known chemical properties and the latter targeting all detectable components. The marker approach uses specific chemical compounds with known molecular structures, while the multi-compound approach uses both chemical compounds with known structures and those with partial chemical information e.g. retention times, mass spectra and ultraviolet spectra. Apart from chromatographic techniques, new techniques such as oscillating and electrochemistry fingerprints have been developed for quality control. Chemometric resolution methods are widely used for component deconvolution and data comparison. Pattern recognition techniques are used for authentication of herbal medicines.
Contemporary evidence: baseline data from the D2B Alliance
Authors: Bradley Elizabeth H , Nallamothu Brahmajee K , Stern Amy F , Byrd Jason R , Cherlin Emily J , Wang Yongfei , Yuan Christina , Nembhard Ingrid , Brush John E , Krumholz Harlan M
Published: August 2008

Background

Less than half of U.S. hospitals meet guidelines for prompt treatment of ST-segment elevation myocardial infarction (STEMI). The Door-to-Balloon (D2B) Alliance is a collaborative effort of more than 900 hospitals committed to implementing a set of evidence-based strategies for reducing D2B time. This study presents data on (1) the prevalence of evidence-based strategies in U.S. hospitals that participated in the D2B Alliance and (2) identifies key hospital characteristics associated with their use.

Methods

We conducted a cross-sectional study of U.S. hospitals that joined the D2B Alliance through a Web-based survey about their current practices for patients with STEMI who received primary percutaneous coronary intervention (PCI). We used multivariate logistic regression to identify hospital characteristics associated with use of each strategy.

Results

Of the 915 U.S. hospitals enrolled in the D2B Alliance as of June 2007, 797 (87%) completed the survey. Only 30.4% of responding hospitals reported employing at least 4 of the 5 key strategies (emergency medicine activates catheterization laboratory, single-call activation, expectation that catheterization team is available in the laboratory within 20–30 minutes after page, prompt data feedback on D2B times, use of pre-hospital electrocardiograms to activate the laboratory while the patient is en route to the hospital); 9.3% employed none of the strategies. There was no clear pattern of correlation between hospital characteristics and reported strategies.

Conclusion

As of 2007, many hospitals had implemented few of the key strategies to reduce D2B time, suggesting substantial opportunity to improve care for patients with STEMI.
PhosCalc: A tool for evaluating the sites of peptide phosphorylation from Mass Spectrometer data
Authors: MacLean Daniel , Burrell Michael A , Studholme David J , Jones Alexandra ME
Published: August 2008

Background

We have created a software implementation of a published and verified method for assigning probabilities to potential phosphorylation sites on peptides using mass spectrometric data. Our tool, named PhosCalc, determines the number of possible phosphorylation sites and calculates the theoretical masses for the b and y fragment ions of a user-provided peptide sequence. A corresponding user-provided mass spectrum is examined to determine which putative b and y ions have support in the spectrum and a probability score is calculated for each combination of phosphorylation sites.

Findings

We test the implementation using spectra of phosphopeptides from bovine beta-casein and we compare the results from the implementation to those from manually curated and verified phosphopeptides from our own experiments. We find that the PhosCalc scores are capable of helping a user to identify phosphorylated sites and can remove a bottleneck in high throughput proteomics analyses.

Conclusion

PhosCalc is available as a web-based interface for examining up to 100 peptides and as a downloadable tool for examining larger numbers of peptides. PhosCalc can be used to speed up identification of phosphorylation sites and can be easily integrated into data handling pipelines making it a very useful tool for those involved in phosphoproteomic research.
Comparison of molecular phenotypes of ductal carcinoma in situand invasive breast cancer
Authors: Tamimi Rulla M , Baer Heather J , Marotti Jonathan , Galan Mark , Galaburda Laurie , Fu Yineng , Deitz Anne C , Connolly James L , Schnitt Stuart J , Colditz Graham A , Collins Laura C
Published: August 2008

Introduction

At least four major categories of invasive breast cancer that are associated with different clinical outcomes have been identified by gene expression profiling: luminal A, luminal B, human epidermal growth factor receptor 2 (HER2) and basal-like. However, the prevalence of these phenotypes among cases of ductal carcinoma in situ (DCIS) has not been previously evaluated in detail. The purpose of this study was to compare the prevalence of these distinct molecular subtypes among cases of DCIS and invasive breast cancer.

Methods

We constructed tissue microarrays (TMAs) from breast cancers that developed in 2897 women enrolled in the Nurses' Health Study (1976 to 1996). TMA slides were immunostained for oestrogen receptor (ER), progesterone receptor (PR), HER2, cytokeratin 5/6 (CK5/6) and epidermal growth factor receptor (EGFR). Using these immunostain results, cases were grouped into molecularly defined subtypes.

Results

The prevalence of the distinct molecular phenotypes differed significantly between DCIS (n = 272) and invasive breast cancers (n = 2249). The luminal A phenotype was significantly more frequent among invasive cancers (73.4%) than among DCIS lesions (62.5%) (p = 0.0002). In contrast, luminal B and HER2 molecular phenotypes were both more frequent among DCIS (13.2% and 13.6%, respectively) as compared with invasive tumours (5.2% and 5.7%, respectively) (p < 0.0001). The basal-like phenotype was more frequent among the invasive cancers (10.9%) than DCIS (7.7%), although this difference was not statistically significant (p = 0.15). High-grade DCIS and invasive tumours were more likely to be HER2 type and basal-like than low- or intermediate-grade lesions. Among invasive tumours, basal-like and HER2 type tumours were more likely to be more than 2 cm in size, high-grade and have nodal involvement compared with luminal A tumours.

Conclusion

The major molecular phenotypes previously identified among invasive breast cancers were also identified among cases of DCIS. However, the prevalence of the luminal A, luminal B and HER2 phenotypes differed significantly between DCIS and invasive breast cancers.