bluuebunny/crossref_metadata_2025 huggingface dataset:
Enterococcal Biofilm Formation and Virulence in an Optimized Murine Model of Foreign Body-Associated Urinary Tract Infections
Authors: Guiton Pascale S. , Hung Chia S. , Hancock Lynn E. , Caparon Michael G. , Hultgren Scott J.
Published: August 2010

Catheter-associated urinary tract infections (CAUTIs) constitute the majority of nosocomial UTIs and pose significant clinical challenges. Enterococcal species are among the predominant causative agents of CAUTIs. However, very little is known about the pathophysiology ofEnterococcus-mediated UTIs. We optimized a murine model of foreign body-associated UTI in order to mimic conditions of indwelling catheters in patients. In this model, the presence of a foreign body elicits major histological changes and induces the expression of several proinflammatory cytokines in the bladder. In addition, in contrast to naïve mice, infection of catheter-implanted mice withEnterococcus faecalisinduced the specific expression of interleukin 1β (IL-1β) and macrophage inflammatory protein 1α (MIP-1α) in the bladder. These responses resulted in a favorable niche for the development of persistentE. faecalisinfections in the murine bladders and kidneys. Furthermore, biofilm formation on the catheter implantin vivocorrelated with persistent infections. However, the enterococcal autolytic factors GelE and Atn (also known as AtlA), which are important in biofilm formationin vitro, are dispensablein vivo. In contrast, the housekeeping sortase A (SrtA) is critical for biofilm formation and virulence in CAUTIs. Overall, this murine model represents a significant advance in the understanding of CAUTIs and underscores the importance of urinary catheterization duringE. faecalisuropathogenesis. This model is also a valuable tool for the identification of virulence determinants that can serve as potential antimicrobial targets for the treatment of enterococcal infections.
HIERARCHIES OF PIECEWISE TESTABLE LANGUAGES
Authors: KLÍMA ONDŘEJ , POLÁK LIBOR
Published: August 2010

The classes of languages which are Boolean combinations of languages of the form [Formula: see text] for a fixed k ≥ 0, form a natural hierarchy within piecewise testable languages and have been studied by Simon, Blanchet-Sadri, Volkov and others. The main issues were the existence of finite bases of identities for the corresponding pseudovarieties of monoids and monoids generating these pseudovarieties.

Here we deal with similar questions concerning the finite unions and positive Boolean combinations of the languages of the form above. In the first case the corresponding pseudovarieties are given by a single identity, in the second case there are finite bases for k equals to 1 and 2 and there is no finite basis for k ≥ 4 (the case k = 3 remains open). All the pseudovarieties are generated by a single algebraic structure.
TREE AUTOMATA WITH GLOBAL CONSTRAINTS
Authors: FILIOT EMMANUEL , TALBOT JEAN-MARC , TISON SOPHIE
Published: August 2010

We define tree automata with global equality and disequality constraints (TAGED). TAGEDs can test (dis)equalities between subtrees which may be arbitrarily faraway. In particular, they are equipped with an equality relation and a disequality relation on states, so that whenever two subtrees t and t′ evaluate (in an accepting run) to two states which are in the (dis)equality relation, they must be (dis)equal. We study several properties of TAGEDs, and prove emptiness decidability of for several expressive subclasses of TAGEDs.
UNAMBIGUOUS SHARED-MEMORY SYSTEMS
Authors: MORIN RÉMI
Published: August 2010

Shared-memory systems appear as a generalization of asynchronous cellular automata. In this paper we relate the partial-order semantics of shared-memory systems to Mazurkiewicz trace languages by means of a new refinement construction. We show that a set of labeled partial orders is recognized by some unambiguous shared-memory system if and only if it is definable in monadic second-order logic and media-bounded.
MEASUREMENT OF ELEMENTAL DISTRIBUTIONS IN MOUSE BRAIN BY USING SUBMILLI-PIXE CAMERA
Authors: FUJIKI K. , MATSUYAMA S. , ISHII K. , YAMAZAKI H. , TERAKAWA A. , KIKUSHI Y. , FUJIWARA M. , KAWAMURA Y. , OKURA S. , FUJIKAWA M. , CATELLA G. , HASHIMOTO Y. , HATORI Y. , HAMADA N. , SAKURAI E. , YANAI K.
Published: August 2010

In a biological body, trace elements including metallic elements play important roles. Knowing their spatial distribution and amounts, we can find out some relations among a physiological role of the trace element in vivo, the function, and the disease appearance. In this study, we investigated a method to obtain elemental distributions in whole brain slice taken from mental disease model mice and control mice using in-air submilli-PIXE camera at Tohoku University. We administered 5-BrdU that was the analogue of the thymidine as a marker to detect a new born cell in especially the dentate gyrus of the hippocampus. We obtained the elemental distributions of the whole brain of subject and control mice. From elemental distributions of the brain of a mental disease model mouse, a brain contained light elements, such as P , S , Cl and K , which were uniformly distributed over the brain. Fe was accumulated in the specific area of brain. Elemental concentration of Fe was more than 10 times higher than that in the other. However, the accumulation of iron in brain slices was not observed in those of control mice. Zn is accumulated in the vicinity in hippocampus. Br was uniformly distributed over the brain. The submilli-PIXE camera will provide a powerful tool for this research.
NEW FORMS OF BRST SYMMETRY IN RIGID ROTOR
Authors: RAI SUMIT KUMAR , MANDAL BHABANI PRASAD
Published: August 2010

We derive the different forms of BRST symmetry by using the Batalin–Fradkin–Vilkovisky formalism in a rigid rotor. The so-called "dual-BRST" symmetry is obtained from the usual BRST symmetry by making a canonical transformation in the ghost sector. On the other hand, a canonical transformation in the sector involving Lagrange multiplier and its corresponding momentum leads to a new form of BRST as well as dual-BRST symmetry.
RIGHT-HANDED SNEUTRINO CURVATON AND NON-GAUSSIANITY
Authors: LIN CHIA-MIN , CHEUNG KINGMAN
Published: August 2010

In this paper, we explore the parameter space for a Right-Handed (RH) sneutrino curvaton that can generate large non-Gaussianity without assuming any particular inflation sector. The mass of the RH sneutrino is suggested from a discussion on the initial condition of the curvaton field. It is shown that a small Yukawa coupling is generally required for a successful RH sneutrino curvaton. However, the Yukawa coupling can be larger if we consider the braneworld scenario. Some general discussion about the spectral index in curvaton scenario is also provided.
Anesthesia for Pediatric Deep Brain Stimulation
Authors: Sebeo Joseph , Deiner Stacie G. , Alterman Ron L. , Osborn Irene P.
Published: August 2010

In patients refractory to medical therapy, deep brain stimulations (DBSs) have emerged as the treatment of movement disorders particularly Parkinson's disease. Their use has also been extended in pediatric and adult patients to treat epileptogenic foci. We here performed a retrospective chart review of anesthesia records from 28 pediatric cases of patients who underwent DBS implantation for dystonia using combinations of dexmedetomidine and propofol-based anesthesia. Complications with anesthetic techniques including airway and cardiovascular difficulties were analyzed.
Acute Impact of Moderate-Intensity and Vigorous-Intensity Exercise Bouts on Daily Physical Activity Energy Expenditure in Postmenopausal Women
Authors: Wang Xuewen , Nicklas Barbara J.
Published: August 2010

This study determined whether performing a single moderate- or vigorous-intensity exercise bout impacts daily physical activity energy expenditure (PAEE, by accelerometer). Overweight/obese postmenopausal women underwent a 5-month caloric restriction and moderate- (n=18) or vigorous-intensity (n=18) center-based aerobic exercise intervention. During the last month of intervention, in women performing moderate-intensity exercise, PAEE on days with exercise (577.7±219.7kcal⋅d−1) was higher (P=.011) than on days without exercise (450.7±140.5kcal⋅d−1); however, the difference (127.0±188.1kcal⋅d−1) was much lower than the energy expended during exercise. In women performing vigorous-intensity exercise, PAEE on days with exercise (450.6±153.6kcal⋅d−1) was lower (P=.047) than on days without exercise (519.2±127.4kcal⋅d−1). Thus, women expended more energy on physical activities outside of prescribed exercise on days they did NOT perform center-based exercise, especially if the prescribed exercise was of a higher intensity.
Loss of miR-200c Expression Induces an Aggressive, Invasive, and Chemoresistant Phenotype in Non–Small Cell Lung Cancer
Authors: Ceppi Paolo , Mudduluru Giridhar , Kumarswamy Regalla , Rapa Ida , Scagliotti Giorgio V. , Papotti Mauro , Allgayer Heike
Published: August 2010

The development of metastases is the main reason for cancer-related death in non–small cell lung cancer (NSCLC). The initiation of metastasis involves an increase in cell motility mediated by the loss of cell-cell adhesion caused by E-cadherin repression, in a process commonly known as epithelial-to-mesenchymal transition. A role for microRNA-200 family members in regulating epithelial-to-mesenchymal transition has recently been indicated but data about their expression in lung tumors is still unavailable. The present study investigated the expression of miR-200c in a panel of NSCLC cell lines (n = 9), and a strong inverse correlation with invasion was detected. Reintroduction of miR-200c into highly invasive/aggressive NSCLC cells induced a loss of the mesenchymal phenotype by restoring E-cadherin and reducing N-cadherin expression, and inhibited in vitro cell invasion as well as in vivo metastasis formation. Moreover, miR-200c overexpression restored the sensitivity of NCI-H1299 cells to cisplatin and cetuximab. Hypermethylation of the promoter region was found to be responsible for the loss of miR-200c in invasive cells, as evaluated by 5-aza-2′-deoxycytidine treatment, methylation-specific PCR, and bisulfite sequencing. In primary tumor specimens obtained from 69 patients with consecutively resected NSCLC, lower miR-200c expression levels were found to be associated with a poor grade of differentiation (P = 0.04), a higher propensity to lymph node metastases (P < 0.01), and with a lower E-cadherin expression (P = 0.01). These data indicate that the loss of miR-200c expression induces an aggressive, invasive, and chemoresistant phenotype, and that assessment of its expression could contribute to a better clinicopathologic definition of patients with NSCLC. Mol Cancer Res; 8(9); 1207–16. ©2010 AACR.
Impairment of Aerobic Glycolysis by Inhibitors of Lactic Dehydrogenase Hinders the Growth of Human Hepatocellular Carcinoma Cell Lines
Authors: Fiume Luigi , Manerba Marcella , Vettraino Marina , Di Stefano Giuseppina
Published: August 2010

Background/Aims:By reducing the number of ATP molecules produced via aerobic glycolysis, the inhibition of lactic dehydrogenase (LDH) should hinder the growth of neoplastic cells without damaging the normal cells which do not rely on this metabolic pathway for their energetic needs. Here, we studied the effect of oxamic and tartronic acids, 2 inhibitors of LDH, on aerobic glycolysis and cell replication of HepG2 and PLC/PRF/5 cells, 2 lines from human hepatocellular carcinomas. Methods:Aerobic glycolysis was measured by calculating the amounts of lactic acid formed. The effect on replication was assessed by culturing the cells in both standard conditions and glucose-deprived medium, which was used to shut down aerobic glycolysis. Results: The oxamic and tartronic acids inhibited aerobic glycolysis, impaired the growth of both cell lines and also induced an increased expression of p53-upregulated modulator of apoptosis, a signal of cell death. A strong impairment of cell replication by oxamic acid was only found when the cells were cultured in the presence of glucose, indicating that it was for the most part owing to inhibition of aerobic glycolysis. Conclusions:Inhibition of aerobic glycolysis achieved by blocking LDH could be useful in the treatment of human hepatocellular carcinomas. Without interfering with glucose metabolism in normal cells, it could hinder cell growth by itself and could also enhance the chemotherapeutic index of associated anticancer agents by decreasing the levels of ATP selectively in neoplastic cells.
Expression of Genes Involved in Lipid Metabolism in Men with Impaired Glucose Tolerance: Impact of Insulin Stimulation and Weight Loss
Authors: Konings E. , Corpeleijn E. , Bouwman F.G. , Mariman E.C. , Blaak E.E.
Published: August 2010

Background:The impaired glucose tolerance (IGT) state is characterized by insulin resistance. Disturbances in fatty acid (FA) metabolism may underlie this reduced insulin sensitivity. The aim of this study was to investigate whether the prediabetic state is accompanied by changes in the expression of genes involved in FA handling during fasting and in insulin-mediated conditions and to study the impact of weight loss. Methods:Seven IGT men and 5 men with normal glucose tolerance (NGT), comparable in terms of age and BMI, participated in the study. The 5 IGT men followed a 12-week weight loss program. Muscle biopsies were taken and the expression of 6 genes was investigated. Results:Subjects had a reduction of 15.5 ± 4.3 kg in body weight. Baseline gene expression was not different between NGT and IGT men. After a hyperinsulinemic clamp, there was an overall upregulation of PGC1α, SREBP-1c, SREBP-2, and ACC-2. The upregulation of SREBP-2 was more pronounced in IGT men (p = 0.049). Weight loss significantly increased insulin sensitivity by 71%, which was not reflected in altered gene expression profiles. Conclusions:SREBP-2 shows altered insulin responsiveness in IGT men compared with NGT men, while there were no differences in basal gene expression.
Comparative Effectiveness of Paricalcitol versus Cinacalcet for Secondary Hyperparathyroidism in Patients Receiving Hemodialysis
Authors: Schumock Glen T. , Walton Surrey M. , Lee Todd A. , Marx Steven E. , Audhya Paul , Andress Dennis L.
Published: August 2010

Background/Aims: Parathyroidectomies are performed when medical therapy fails to control secondary hyperparathyroidism in hemodialysis patients. The objective of this study was to compare parathyroidectomy rates in secondary hyperparathyroidism patients treated with paricalcitol or cinacalcet. Methods: Retrospective cohort study using health insurance claims from January 2001 through June 2007 for adult hemodialysis patients who were new users of paricalcitol or cinacalcet. Subjects had a minimum of 12 months’ enrollment prior to initiation of treatment and at least 30-day follow-up. Results: We identified 1,387 paricalcitol- and 1,317 cinacalcet-treated patients. The parathyroidectomy incident rate was 74% lower in the paricalcitol (0.58 per 100 patient-years) compared to the cinacalcet (2.24 per 100 patient-years) cohort, with an unadjusted rate ratio of 0.26 (95% CI 0.12–0.52). The time to parathyroidectomy from medication initiation was longer for paricalcitol than cinacalcet; however, it was not statistically significant (535 vs. 443 days, p = 0.377). A Cox proportional hazard model that adjusted for age, gender, obesity, significantly different comorbidities, and duration of hemodialysis resulted in an adjusted risk reduction for parathyroidectomy of 79% (HR = 0.21, 95% CI 0.10–0.46) for paricalcitol compared to cinacalcet. Conclusion: These data suggest that long-term treatment with paricalcitol is associated with fewer parathyroidectomies when compared to cinacalcet. Further comparative studies are needed to validate these results.
Deficiency of Antigen-Presenting Cell Invariant Chain Reduces Atherosclerosis in Mice
Authors: Sun Jiusong , Hartvigsen Karsten , Chou Meng-Yun , Zhang Yadong , Sukhova Galina K. , Zhang Jie , Lopez-Ilasaca Marco , Diehl Cody J. , Yakov Niva , Harats Dror , George Jacob , Witztum Joseph L. , Libby Peter , Ploegh Hidde , Shi Guo-Ping
Published: August 2010

Background—

Adaptive immunity and innate immunity play important roles in atherogenesis. Invariant chain (CD74) mediates antigen-presenting cell antigen presentation and T-cell activation. This study tested the hypothesis that CD74-deficient mice have reduced numbers of active T cells and resist atherogenesis.

Methods and Results—

In low-density lipoprotein receptor–deficient (

Ldlr
−/−

) mice, CD74 deficiency (

Ldlr
−/−
Cd74
−/−

) significantly reduced atherosclerosis and CD25
+
-activated T cells in the atheromata. Although

Ldlr
−/−
Cd74
−/−

mice had decreased levels of plasma immunoglobulin (Ig) G1, IgG2b, and IgG2c against malondialdehyde-modified LDL (MDA-LDL), presumably as a result of impaired antigen-presenting cell function,

Ldlr
−/−
Cd74
−/−

mice showed higher levels of anti–MDA-LDL IgM and IgG3. After immunization with MDA-LDL,

Ldlr
−/−
Cd74
−/−

mice had lower levels of all anti–MDA-LDL Ig isotypes compared with

Ldlr
−/−

mice. As anticipated, only

Ldlr
−/−

splenocytes responded to in vitro stimulation with MDA-LDL, producing Th1/Th2 cytokines. Heat shock protein-65 immunization enhanced atherogenesis in

Ldlr
−/−

mice, but

Ldlr
−/−

Cd74
−/−

mice remained protected. Compared with

Ldlr
−/−

mice,

Ldlr
−/−
Cd74
−/−

mice had higher anti–MDA-LDL autoantibody titers, fewer lesion CD25
+
-activated T cells, impaired release of Th1/Th2 cytokines from antigen-presenting cells after heat shock protein-65 stimulation, and reduced levels of all plasma anti–heat shock protein-65 Ig isotypes. Cytofluorimetry of splenocytes and peritoneal cavity cells of MDA-LDL– or heat shock protein-65–immunized mice showed increased percentages of autoantibody-producing marginal zone B and B-1 cells in

Ldlr
−/−
Cd74
−/−

mice compared with

Ldlr
−/−

mice.

Conclusions—

Invariant chain deficiency in

Ldlr
−/−

mice reduced atherosclerosis. This finding was associated with an impaired adaptive immune response to disease-specific antigens. Concomitantly, an unexpected increase in the number of innate-like peripheral B-1 cell populations occurred, resulting in increased IgM/IgG3 titers to the oxidation-specific epitopes.
Severe Convective Storms—An Overview
Authors: Doswell Charles A.
Published: August 2010

No Abstract available.
Hailstorms
Authors: Knight Charles A. , Knight Nancy C.
Published: August 2010

No Abstract available.
Rain Production in Convective Storms
Authors: Lamb Dennis
Published: August 2010

No Abstract available.
Mesoscale Processes and Severe Convective Weather
Authors: Johnson Richard H. , Mapes Brian E.
Published: August 2010

No Abstract available.
Dynamical Diagnosis: A Comparison of Quasigeostrophy and Ertel Potential Vorticity
Authors: Nielsen-Gammon John W. , Gold David A.
Published: August 2010

Advances in computer power, new forecasting challenges, and new diagnostic techniques have brought about changes in the way atmospheric development and vertical motion are diagnosed in an operational setting. Many of these changes, such as improved model skill, model resolution, and ensemble forecasting, have arguably been detrimental to the ability of forecasters to understand and respond to the evolving atmosphere. The use of nondivergent wind in place of geostrophic wind would be a step in the right direction, but the advantages of potential vorticity suggest that its widespread adoption as a diagnostic tool on the west side of the Atlantic is overdue. Ertel potential vorticity (PV), when scaled to be compatible with pseudopotential vorticity, is generally similar to pseudopotential vorticity, so forecasters accustomed to quasigeostrophic reasoning through the height tendency equation can transfer some of their intuition into the Ertel-PV framework. Indeed, many of the differences between pseudopotential vorticity and Ertel potential vorticity are consequences of the choice of definition of quasigeostrophic PV and are not fundamental to the quasigeostrophic system. Thus, at its core, PV thinking is consistent with commonly used quasigeostrophic diagnostic techniques.
Finescale Radar Observations of a Dryline during the International H2O Project (IHOP_2002)
Authors: Weiss Christopher C. , Bluestein Howard B. , Pazmany Andrew L. , Geerts Bart
Published: August 2010

A case study of a double dryline on 22 May 2002 is presented. Mobile, 3-mm-wavelength Doppler radars from the University of Massachusetts and the University of Wyoming (Wyoming cloud radar) were used to collect very fine resolution vertical-velocity data in the vicinity of each of the moisture gradients associated with the drylines. Very narrow (50–100 m wide) channels of strong upward vertical velocity (up to 8 m s–1) were measured in the convergence zone of the easternmost dryline, larger in magnitude than reported with previous drylines. Distinct areas of descending motion were evident to the east and west of both drylines. Radar data are interpreted in the context of other observational platforms available during the International H2O Project (IHOP-2002). a variational ground-based mobile radar data processing technique was developed and applied to pseudo-dual-Doppler data collected during a rolling range-height indicator deployment. It was found that there was a secondary (vertical) circulation normal to the easternmost moisture gradient; the circulation comprised an easterly component near-surface flow to the east, a strong upward vertical component in the convergence zone, a westerly return, flow above the convective boundary layer, and numerous regions of descending motion, the most prominent approximately 3–5 km to the east of the surface convergence zone.
Linking Weather and Climate
Authors: Dole Randall M.
Published: August 2010

Historically, the atmospheric sciences have tended to treat problems of weather and climate separately. The real physical system, however, is a continuum, with short-term (minutes to days) “weather” fluctuations influencing climate variations and change, and, conversely, more slowly varying aspects of the system (typical time scales of a season or longer) affecting the weather that is experienced. While this past approach has served important purposes, it is becoming increasingly apparent that in order to make progress in addressing many socially important problems, an improved understanding of the connections between weather and climate is required.

This overview summarizes the progress over the last few decades in the understanding of the phenomena and mechanisms linking weather and climate variations. The principal emphasis is on developments in understanding key phenomena and processes that bridge the time scales between synoptic-scale weather variability (periods of approximately 1 week) and climate variations of a season or longer. Advances in the ability to identify synoptic features, improve physical understanding, and develop forecast skill within this time range are reviewed, focusing on a subset of major, recurrent phenomena that impact extratropical wintertime weather and climate variations over the Pacific–North American region. While progress has been impressive, research has also illuminated areas where future gains are possible. This article concludes with suggestions on near-term directions for advancing the understanding and capabilities to predict the connections between weather and climate variations.
An Empirical Perspective on Cold Fronts
Authors: Kessler Edwin
Published: August 2010

Oklahoma Mesonetwork data are used to illustrate important atmospheric features that are not well shown by the usual synoptic data. For example, some shifts of wind from south to north that are shown as cold fronts on synoptic charts are not cold fronts by any plausible definition. As previously discussed by Fred Sanders and others, such errors in analysis can be reduced by knowledge of the wide variety of weather phenomena that actually exists, and by more attention to temperatures at the earth's surface as revealed by conventional synoptic data. Mesoscale data for four cases reinforce previous discussions of the ephemeral nature of fronts and deficiencies in the usual analyses of cold fronts. One type of misanalyzed case involves post-cold-frontal boundary layer air that is warmer than the prefrontal air. A second type is usually nocturnal, with a rise of local temperature during disruption of an inversion and a wind shift with later cooling that accompanies advection of a climatological gradient of temperature.
New sutureless ‘atrial- mitral-valve prosthesis’ for minimally invasive mitral valve therapy
Authors: Spillner J. , Goetzenich A. , Amerini A. , Holtmannspötter O. , Deichmann T. , Schmitz Ch , Autschbach R. , Dohmen G.
Published: August 2010

Incompetence is the most relevant dysfunction of the mitral valve. Surgical replacement and reconstruction is the treatment of choice whereas trans-catheter replacement or repair of mitral valve regurgitation proved demanding. We aimed for a new sutureless approach to anchor a biological heart valve in the mitral position without major surgery by inserting a valve-carrying hollow body into the left atrium.

A mould representing the porcine left atrium from the pulmonary veins as far as the mitral valve was created. A superelastic Nitinol-skeleton was sutured onto a warp knitted tubular bifurcation of polyvinylidene fluoride (PVDF) multifilaments fitting the mould. This new self-expandable composite-material hollow body customized to the porcine anatomy was equipped with a commercially available biological heart valve. The functionality of this prosthesis was investigated in a circulatory mock loop simulator and the overall properties were examined in an open animal operation. The left atrium was incised and the prosthesis was placed in eight female pigs of 70 kg, under extracorporeal circulation. Prior to implantation, an artificial valve incompetence was created. Hemodynamic, echocardiographic, and radiological examinations were performed. A post mortem examination of the entire heart was performed.

In the simulator we could demonstrate that the composite-material hollow body exhibited enough self-expansion to anchor onto the surrounding structures and that the function of the expanded valve was not compromised. In the animal, the prostheses walls almost completely adapted to surrounding structures leading to an exclusion of the left atrium. Sufficient treatment of mitral regurgitation was displayed hemodynamically and by echocardiography, although overall visualization was difficult. Therefore, in the last four animals a CT scan was performed demonstrating full expansion. Autopsy revealed an excellent anchorage of the prostheses. The relevant intracavitary injury and thrombotic formation were not seen.

By the use of a composite-material self-expanding hollow body it is possible exclude a complete heart chamber and thereby to anchor a biological heart valve without sutures.
Cooperative AUV Navigation using a Single Maneuvering Surface Craft
Authors: Fallon Maurice F , Papadopoulos Georgios , Leonard John J , Patrikalakis Nicholas M
Published: August 2010

In this paper we describe the experimental implementation of an online algorithm for cooperative localization of submerged autonomous underwater vehicles (AUVs) supported by an autonomous surface craft. Maintaining accurate localization of an AUV is difficult because electronic signals, such as GPS, are highly attenuated by water. The usual solution to the problem is to utilize expensive navigation sensors to slow the rate of dead-reckoning divergence. We investigate an alternative approach that utilizes the position information of a surface vehicle to bound the error and uncertainty of the on-board position estimates of a low-cost AUV. This approach uses the Woods Hole Oceanographic Institution (WHOI) acoustic modem to exchange vehicle location estimates while simultaneously estimating inter-vehicle range. A study of the system observability is presented so as to motivate both the choice of filtering approach and surface vehicle path planning. The first contribution of this paper is to the presentation of an experiment in which an extended Kalman filter (EKF) implementation of the concept ran online on-board an OceanServer Iver2 AUV while supported by an autonomous surface vehicle moving adaptively. The second contribution of this paper is to provide a quantitative performance comparison of three estimators: particle filtering (PF), non-linear least-squares optimization (NLS), and the EKF for a mission using three autonomous surface craft (two operating in the AUV role). Our results indicate that the PF and NLS estimators outperform the EKF, with NLS providing the best performance.
Forecasting volatilities in equity, bond and money markets: A market-based approach
Authors: Wang Kent
Published: August 2010

This study examines the forecasting power of the most popular volatility forecasting models in the S&P 500 index market, the Eurodollar futures market, and the 30-year US T-Bond futures market at a daily level using a market-based option-pricing error approach. Comparison has been made between two methods including and excluding implied volatility in option-pricing error approach in forecasting next-day volatilities. To remove any advantage to option-implied volatility, the analysis is performed in two steps. Spurious regression biases and biases in the measurement of volatility forecasts are controlled for.The evidence from this paper supports the use of implied volatility as a proxy for market volatility, as it works best in forecasting next-day realized volatility in all the three US markets. The appropriateness of including implied volatility in option-pricing error approach is also discussed.
An experimental study of autoclaved aerated concrete lintels strengthened with externally bonded glass FRP
Authors: Memari Ali M , Lepage Andres , Setthachayanon Jarin
Published: August 2010

This article presents the experimental data obtained from four-point loading of AAC lintels and compares the measured failure loads with capacities predicted using the conventional strength-design method. Fiber-reinforced polymer (FRP) fabrics are used to strengthen existing concrete structures as an alternative to externally bonded steel plates. Design approaches have been developed for application of FRP on conventional concrete surfaces, but there are other types of concrete materials that have not been sufficiently studied for FRP application. Autoclaved aerated concrete (AAC) is one such material introduced in the US market in the mid 1990s. There is an interest in evaluating the feasibility of application of FRP to retrofit existing structures or components made of AAC (e.g., AAC lintels, floor panels, wall panels, etc.). The specimens used in this study include AAC lintels without FRP and with two alternative schemes of FRP applied to the external lintel surfaces for flexural and shear strengthening. Specimens of conventional reinforced concrete were also tested for comparison with AAC when both are strengthened with FRP. The measured test data provide a basis for evaluating the accuracy of existing strength-design equations to predict the capacity of such specimens. Test results show that the application of FRP at the bottom of the lintels, in combination with U-wrap at the ends of the lintels, increases the load and deflection capacities. Comparison of test results and calculated strengths shows that the existing guidelines such as ACI 440.2R and ACI 523.4R give safe estimates of shear and flexural strength for FRP-enhanced AAC lintels.
Multitemperature Stability and Degradation Characteristics of Pergolide Mesylate Oral Liquid
Authors: Shank Brandon R. , Ofner Clyde M.
Published: August 2010

The stability of pergolide mesylate in an oral aqueous liquid was studied. Stability and solubility data were used to determine the degradation characteristics of the drug in this formulation. Samples were stored in the dark at 35°C, 45°C, and 60°C. At 1, 2, 4, 8, 12, and 16 weeks, samples were removed and stored in a −80°C freezer for high performance liquid chromatography (HPLC) assay at a later date. The initial drug concentration of 0.30 mg/mL was determined by assay after storage at −80°C. A solubility of 6.9 mg/mL was found for pergolide mesylate in the oral liquid at room temperature with a relative standard deviation (RSD) of 4.0%. The degradation process is considered first-order at 25°C and 35°C. At higher temperatures (45°C and 60°C), a color change and curvature at the latter time points in degradation profiles are ascribed to the presence of methylcellulose. The activation energy calculated for degradation of pergolide mesylate in the oral liquid was 21.3 kcal/mol. The time to reach 90% potency (t90) values were calculated to be 43 days and 3 days, respectively, for storage at 25°C and 35°C. Drug concentrations up to ~6 mg/mL can be maintained as a solution at room temperature with this formulation.
What Whitehall?
Authors: Greer Scott L. , Jarman Holly
Published: August 2010

This article asks who works in Whitehall today. We argue that there are points of consensus about the nature of ‘Whitehall’, including generalism, internal labour markets, Oxbridge education, and lifetime careers. An analysis of 306 biographies of the top team of the UK civil service, which goes beyond existing published use of biographical data on the topic, allows us to compare the civil service with this model. We find that in every respect the descriptive usefulness of a Whitehall model is weak. Whitehall is no longer marked by internal labour markets, Oxbridge dominance, or lifetime careers, and there are signs of reduced generalism. Furthermore, many of the most politically salient departments appear to be leading the way towards a different public sector model premised on managerial, policy expertise rather than civil service generalism and loyalty.
Re-Inventing Public Education
Authors: Grek Sotiria , Ozga Jenny
Published: August 2010

This article focuses on the changing role of knowledge in education policy making within the knowledge society. Through an examination of key policy texts, the Scottish case of Integrated Children Services provision is used to exemplify this new trend. We discuss the ways in which knowledge is being used in order to re-configure education as part of a range of public services designed to meet individuals’ needs. This, we argue, has led to a ‘scientization’ of education governance where it is only knowledge, closely intertwined with action (expressed as ‘measures’) that can reveal problems and shape solutions. The article concludes by highlighting the key role of knowledge policy and governance in orienting education policy making through a re-invention of the public role of education.
An exact method for link parameter estimation in error benchmarking: an application to Phase II two-stage single arm oncology trials
Authors: Barnes Christopher N , Rai Shesh N
Published: August 2010

Bayesian trial designs rely on the specification of a vague data prior to the determination of trial outcome. Phase II two-stage single arm oncology trials have a generally small sample size which may not provide the necessary amount of data to outweigh a misspecified or overly optimistic prior. To account for this issue, clinicians may wish to benchmark Bayesian errors with frequentist measures of trial validity, Type I and Type II errors. A confidence prior, reflecting the clinician’s confidence in the efficacy of the treatment before data accrual, is used to equate the errors across design strategies. An exact method, modelling both the inherent small sample size and multi-stage decision process of Phase II single arm trials, is presented for constructing the confidence prior.
Challenges of Capacity Building in Multisector Community Health Alliances
Authors: Alexander Jeffrey A. , Christianson Jon B. , Hearld Larry R. , Hurley Robert , Scanlon Dennis P.
Published: August 2010

Capacity building is often described as fundamental to the success of health alliances, yet there are few evaluations that provide alliances with clear guidance on the challenges related to capacity building. This article attempts to identify potential challenges of capacity building in multistakeholder health alliances. The study uses a multiple case study design to identify potential challenges and trade-offs associated with capacity building in four community health alliances in the United States. Multiple challenges were found to be common across the four alliances, including specifying appropriate governance structures and decision-making frameworks, aligning stakeholder interests with the vision of the alliance, balancing short-term objectives with long-term goals, and securing resources to sustain the effort without compromising it. These challenges often involved trade-offs and choices that alliances need to prepare for if they are to approach capacity building in a planful rather than a reactive manner.
Incidence of and risk factors for type-2 diabetes in a general population: The Tromsø Study
Authors: Joseph Josepha , Svartberg Johan , Njølstad Inger , Schirmer Henrik
Published: August 2010

Aims: To determine the gender-specific incidence and risk factors of type-2 diabetes mellitus (T2DM) in a general population. Methods: The study is based on 12,431 men and 13,737 women aged 25-98 years, attending the Tromsø Study in 1994 and followed through 2005, who did not have diabetes when entering the study. Sex-specific hazard ratios were estimated from Cox proportional hazard models. Results: A total of 522 cases of T2DM were registered, 308 among men and 214 among women. The age-standardised incidence rate was higher in men than in women, 2.6 (95% CI 2.32—2.90) and 1.6 (95% CI 1.40—1.83) per 1000 person-years, respectively. In multivariate survival analysis, age, body mass index (BMI), triglycerides, high-density lipoprotein (HDL) cholesterol, hypertension, family history of diabetes, low education and smoking were independent predictors of T2DM in both genders (p>0.05). Total cholesterol and lack of leisure-time physical activity were independent predictors in men only. We found an interaction between HDL cholesterol and triglyceride levels (p>0.001) and between triglyceride levels and a positive family history of diabetes (p = 0.04). These interactions were independent of BMI. A positive family history combined with triglycerides in the highest tertile and BMI >25 kg/m2 conveyed a 10-year risk of T2DM of 10% (95% CI 8—12%) vs. 0.2% (95% CI 0.08—0.31%) for the lowest risk group. Conclusions: A family history of diabetes, elevated BMI, and high triglyceride levels identifies independent of cardiovascular risk factors, a group with especially high risk of T2DM.
Risk factors for violence exposure and attributable healthcare costs: Results from the Danish national health interview surveys
Authors: Helweg-Larsen Karin , Sørensen Jan , Brønnum-Hansen Henrik , Kruse Marie
Published: August 2010

Aims: To describe the characteristics of men and women exposed to physical violence, to identify risk factors for violence exposure and to quantify the attributable healthcare costs of violence. Methods: The Danish national health interview surveys of 2000 and 2005 included data on exposure to defined forms of physical violence over the last 12 months. Respondents who reported exposure to violence during the past year were compared with a reference group of non-exposed respondents, and data were merged with the National Health Registers. We identified risk factors for violence by logistic regression models and used OLS regression for quantification of attributable healthcare costs of violence, including somatic and psychiatric admissions, outpatient contacts, prescriptions and primary health services; and analyzed intimate partner violence separately. Results: Young age, being divorced and drinking more than the recommended amount of alcohol per week were risk factors for violence both for men and women. Total annual healthcare costs, adjusted for age and deliveries, were 787 euros higher on average for women exposed to violence than for non-exposed women, mainly related to psychiatric treatment. For women, no significant cost differences existed between victims of partner violence and non-victims. The total healthcare costs were not higher for exposed men than for non-exposed men, but male victims of partner violence incurred significantly higher costs. Conclusions: Primarily due to costs of psychiatric treatment, male and female victims of violence had higher total healthcare costs than non-exposed people. Whether mental health problems increase the risk of violence exposure or violence is a particular risk factor for health problems cannot be assessed by cross-sectional data alone.
Deep vein thrombosis following hip fracture surgery
Authors: Matharu GS , Porter KM
Published: August 2010

Patients undergoing hip fracture surgery are at increased risk of deep vein thrombosis. There are limited studies of good quality assessing thromboprophylactic therapies in this patient population. Mechanical pumping devices may have a role in hip fracture patients, especially around the perioperative period, though compliance with these devices is a significant problem. Fondaparinux is the most effective pharmacological thromboprophylactic therapy following hip fracture surgery and can be used for extended prophylaxis after hospital discharge. A number of the recently published recommendations from the National Institute for Health and Clinical Excellence do not take into account the best available evidence specifically in patients undergoing hip fracture surgery, with findings from elective arthroplasty patients being extrapolated. Well-designed randomised trials are needed to determine the role of combined thromboprophylaxis, graduated compression stockings and newer oral anticoagulants so that appropriate recommendations can be made in patients undergoing hip fracture surgery.
Oncogenic JAK2V617F requires an intact SH2-like domain for constitutive activation and induction of a myeloproliferative disease in mice
Authors: Gorantla Sivahari P. , Dechow Tobias N. , Grundler Rebekka , Illert Anna Lena , zum Büschenfelde Christian Meyer , Kremer Marcus , Peschel Christian , Duyster Justus
Published: August 2010

The oncogenic JAK2V617F mutation is found in myeloproliferative neoplasms (MPNs) and is believed to be critical for leukemogenesis. Here we show that JAK2V617F requires an intact SH2 domain for constitutive activation of downstream signaling pathways. In addition, there is a strict requirement of cytokine receptor expression for the activation of this oncogene. Further analysis showed that the SH2 domain mutation did not interfere with JAK2 membrane distribution. However, coimmunoprecipitated experiments revealed a role for the SH2 domain in the aggregation and cross-phosphorylation of JAK2V617F at the cell membrane. Forced overexpression of cytokine receptors could rescue the JAK2V617F SH2 mutant supporting a critical role of JAK2V617F abundance for constitutive activation. However, under physiologic cytokine receptor expression the SH2 domain is absolutely necessary for oncogenic JAK2V617F activation. This is demonstrated in a bone marrow transplantation model, in which an intact SH2 domain in JAK2V617F is required for the induction of an MPN-like disease. Thus, our results points to an indispensable role of the SH2 domain in JAK2V617F-induced MPNs.
TAM: A method for enrichment and depletion analysis of a microRNA category in a list of microRNAs
Authors: Lu Ming , Shi Bing , Wang Juan , Cao Qun , Cui Qinghua
Published: August 2010

Background

MicroRNAs (miRNAs) are a class of important gene regulators. The number of identified miRNAs has been increasing dramatically in recent years. An emerging major challenge is the interpretation of the genome-scale miRNA datasets, including those derived from microarray and deep-sequencing. It is interesting and important to know the common rules or patterns behind a list of miRNAs, (i.e. the deregulated miRNAs resulted from an experiment of miRNA microarray or deep-sequencing).

Results

For the above purpose, this study presents a method and develops a tool (TAM) for annotations of meaningful human miRNAs categories. We first integrated miRNAs into various meaningful categories according to prior knowledge, such as miRNA family, miRNA cluster, miRNA function, miRNA associated diseases, and tissue specificity. Using TAM, given lists of miRNAs can be rapidly annotated and summarized according to the integrated miRNA categorical data. Moreover, given a list of miRNAs, TAM can be used to predict novel related miRNAs. Finally, we confirmed the usefulness and reliability of TAM by applying it to deregulated miRNAs in acute myocardial infarction (AMI) from two independent experiments.

Conclusion

TAM can efficiently identify meaningful categories for given miRNAs. In addition, TAM can be used to identify novel miRNA biomarkers. TAM tool, source codes, and miRNA category data are freely available at http://cmbi.bjmu.edu.cn/tam.
Production of erythriod cells from human embryonic stem cells by fetal liver cell extract treatment
Authors: Liu Yu-xiao , Yue Wen , Ji Lei , Nan Xue , Pei Xue-tao
Published: August 2010

Background

We recently developed a new method to induce human stem cells (hESCs) differentiation into hematopoietic progenitors by cell extract treatment. Here, we report an efficient strategy to generate erythroid progenitors from hESCs using cell extract from human fetal liver tissue (hFLT) with cytokines. Human embryoid bodies (hEBs) obtained of human H1 hESCs were treated with cell extract from hFLT and co-cultured with human fetal liver stromal cells (hFLSCs) feeder to induce hematopoietic cells. After the 11 days of treatment, hEBs were isolated and transplanted into liquid medium with hematopoietic cytokines for erythroid differentiation. Characteristics of the erythroid cells were analyzed by flow cytometry, Wright-Giemsa staining, real-time RT-PCR and related functional assays.

Results

The erythroid cells produced from hEBs could differentiate into enucleated cells and expressed globins in a time-dependent manner. They expressed not only embryonic globins but also the adult-globin with the maturation of the erythroid cells. In addition, our data showed that the hEBs-derived erythroid cells were able to act as oxygen carriers, indicating that hESCs could generate functional mature erythroid cells.

Conclusion

Cell extract exposure with the addition of cytokines resulted in robust erythroid -like differentiation of hEBs and these hEBs-derived erythroid cells possessed functions similar to mature red blood cells.