bluuebunny/crossref_metadata_2025 huggingface dataset:
Bacterial infective arthritis following a penetrating stick injury of the stifle joint in a dog
Authors: Clarke S. P. , Ferguson J. F.
Published: July 2012

An eight‐year old, Rottweiler was presented with a chronic non‐weight bearing right pelvic limb ‐lameness and a discharging sinus at the right stifle joint. Fifteen weeks previously a diagnosis of bacterial infective arthritis had been made, presumed attributable to haematogenous spread. Failure to respond to appropriate surgical and medical management resulted in severe joint dysfunction. The poor prognosis for restoration of limb function resulted in limb amputation. Subsequent exploration of the sinus tract and the stifle joint revealed a stick within the craniolateral aspect of the joint. This penetrating stick injury had been responsible for the persistent bacterial infective arthritis.
Setting reference values for exhaled nitric oxide: a systematic review
Authors: Jacinto Tiago , Alving Kjell , Correia Ricardo , Costa‐Pereira Altamiro , Fonseca João
Published: July 2012

Background

The values obtained when the fraction of exhaled nitric oxide (FeNO) is measured are affected by several factors that are specific to the individual patient, making interpretation difficult, especially in the initial assessment of patients with respiratory symptoms.

Methods

Systematic review of studies on FeNO reference values and individual‐specific factors that influence them.

Results

From 3739 references, 15 studies were included. Four studies included children and adolescents. In nine studies, samples were selected from the general population. Most studies reported objective measures for atopy (nine studies), but not for smoking status (one). Significant determinants of FeNO values reported were age and height (seven studies), atopy (six), smoking (four), weight (four), sex (three) and race (three). Additional factors were included in eight studies. R2 was reported in only five studies. The logarithmic transformation of FeNO was inadequately described in seven studies.

Conclusion

There are several equations for FeNO reference values that may be used in clinical practice, although the factors they include and the statistical methods they use vary considerably. We recommend the development of standard methods for the evaluation of normal FeNO data and that reference equations should be formulated based on a predetermined physiological model.
Exercise during cardiac catheterization distinguishes between pulmonary and left ventricular causes of dyspnea in systemic sclerosis patients
Authors: Hager W. David , Collins Irina , Tate Janet P. , Azrin Michael , Foley Raymond , Lakshminarayanan Santha , Rothfield Naomi F.
Published: July 2012

Objective

The cause for shortness of breath among systemic sclerosis (SSc) patients is often lacking. We sought to characterize the hemodynamics of these patients by using simple isotonic arm exercise during cardiac catheterization.

Methods

Catheterization was performed in 173 SSc patients when resting echocardiographic pulmonary systolic pressures were <40 but >40 mmHg post stress. Patients with resting mean pulmonary arterial pressures (mPAP) ≤ 25 and pulmonary arterial wedge pressures (PAWP) ≤ 15 mmHg exercised with 1‐pound hand weights. Normal exercise was defined as a change in mPAP divided by the change in cardiac output (CO) (ΔmPAP/ΔCO) ratio ≤ 2 for patients <50 years (≤3 for >50). An abnormal ΔmPAP/ΔCO ratio, an exercise transpulmonary gradient (TPG) ≥ 15, a PAWP < 20, a ΔTPG > ΔPAWP and a pulmonary vascular resistance (PVR) which increased defined exercise‐induced pulmonary arterial hypertension (EIPAH). An abnormal ΔmPAP/ΔCO ratio, an exercise TPG < 15, a PAWP ≥ 20, a ΔTPG < ΔPAWP and a drop in PVR defined left ventricular diastolic dysfunction (DD). Twelve patients without SSc served as controls.

Results

Pulmonary pressures increased with exercise in 53 patients. Six had EIPAH and 47 had DD. With exercise, mPAP and PAWP were 20 ± 4 and 13 ± 2 in controls, 36 ± 3 and 12 ± 4 in EIPAH and 34 ± 6 and 26 ± 4 in DD. Control ΔmPAP/ΔCO was 0.8 ± 0.7, 7.5 ± 3.9 in EIPAH and 9.1 ± 7.2 in DD. Rest and exercise TPG was normal for control and DD patients but increased (12 ± 4 to 23 ± 4) in EIPAH (P < 0.0001). PVR decreased in DD but increased in EIPAH with exercise.

Conclusions

Exercise during catheterization elucidates the pathophysiology of dyspnea and distinguishes EIPAH from the more common DD in SSc patients.
Careful, Physicalists: Mind–Body Supervenience Can Be Too Superduper
Authors: BALTIMORE JOSEPH A.
Published: July 2012

It has become evident that mind–body supervenience, as merely specifying a covariance between mental and physical properties, is consistent with clearly non‐physicalist views of the mental, such as emergentism. Consequently, there is a push in the physicalist camp for an ontologically more robust supervenience, a “superdupervenience,” that ensures that properties supervening on physical properties are physicalistically acceptable. Jessica Wilson claims that supervenience is made superduper by Condition on Causal Powers (CCP): each individual causal power associated with a supervenient property is numerically identical with a causal power associated with its base property. Furthermore, according to Wilson, a wide variety of physicalist positions, both reductive and non‐reductive, can be seen as relying on CCP to ensure that properties supervening on physical properties are physicalistically acceptable. I argue that imposing CCP on mind–body supervenience fails to ensure that mental properties are physicalistically acceptable. The problem, I contend, is that while CCP may guard against supervenient mental properties being insufficiently grounded in their physical bases it fails to guard against supervenient mental properties being too deeply grounded in their physical bases.
A new euphyllophyte Kunia venusta gen. et sp. nov. from the Middle Devonian of Yunnan, South China
Authors: XIONG Cong‐Hui , WANG De‐Ming , WANG Qi , MENG Mei‐Cen
Published: July 2012

Abstract  Kunia venusta gen. et sp. nov. is reported from the late Middle Devonian (Givetian) Haikou Formation near Kunming City, Yunnan Province, China. This plant has three orders of naked axes that divide pseudomonopodially. The second‐ and third‐order axes occur in a helix. Fertile appendages are distantly spaced and helically inserted to the third‐order axis; they comprise equally dichotomous branches terminated by two clusters of paired and fusiform sporangia. Sterile appendages are dichotomous and distally recurved. A comparison is made with the basal euphyllophytes including the trimerophytes, cladoxylopsids, zygopterids, stauropterids, and some relevant genera of uncertain affinity. The new plant resembles them in dichotomous appendages with terminal elongated sporangia, but differs mainly in the three orders of pseudomonopodial axes bearing helical laterals. It is thus placed in the Euphyllophytina as incertae sedis. It is suggested that an evolutionary divergence in the branching pattern and appendage morphology might have occurred in the Middle Devonian euphyllophytes, that is, maintaining three dimensions versus yielding more or less planation.
When Do Global Pipelines Enhance the Diffusion of Knowledge in Clusters?
Authors: Morrison Andrea , Rabellotti Roberta , Zirulia Lorenzo
Published: July 2012

abstract

Recent studies have stressed the role played by global pipelines in fostering the growth of clusters and innovativeness. In this article, we develop a formal model to investigate when global pipelines contribute to an increase in local knowledge, depending on various characteristics of clusters such as size, knowledge endowment, and the ease of transmission of internal knowledge. This model is an extension ofCowan andJonard's () model in which we introduce the concept of cluster and a role for spatial proximity in the diffusion of knowledge. Our results reveal that there is a natural tendency of actors within global pipelines to act as external stars, rather than gatekeepers of knowledge. Global pipelines are beneficial for the accumulation of knowledge only if the cluster is either characterized by a high‐quality local buzz or is small and weakly endowed in terms of knowledge.
A Preliminary Experimental Assessment of the Utility of Magnetic Oil for Incrementally Improving the Energy Efficiency of an Induction Heating System
Authors: Kucukkomurler Ahmet , Selver Ramazan
Published: July 2012

This paper compares the temperature response of magnetic oil to that of conventional nonmagnetic lubricant oil, in an application of electromagnetic induction heating principles to the design of a system suitable for radiant floor heating. Results of experiments carried out using a closed loop system in which a pump circulates oil from a tank through a heat exchanger are presented. Magnetic oil is found to make a small but nontrivial contribution to the energy efficiency of the system.
Parametric Adjustments to the Rankine Vortex Wind Model for Gulf of Mexico Hurricanes
Authors: Jeong Chan Kwon , Panchang Vijay , Demirbilek Zeki
Published: July 2012

Parametric wind models are often used to reconstruct hurricane wind fields from a limited set of hurricane parameters. Application of the Rankine Vortex and other models used in forecasting Gulf of Mexico hurricanes show considerable differences between the resulting wind speeds and data. The differences are used to guide the development of adjustment factors to improve the wind fields resulting from the Rankine Vortex model. The corrected model shows a significant improvement in the shape, size, and wind speed contours for 14 out of 17 hurricanes examined. The effect on wave fields resulting from the original and modified wind fields are on the order of 4 m, which is important for the estimation of extreme wave statistics.
Numerical Solution of 3-D Water Entry Problems With a Constrained Interpolation Profile Method
Authors: Yang Qingyong , Qiu Wei
Published: July 2012

This paper presents the numerical solutions of slamming problems for 3D bodies entering calm water with vertical and oblique velocities. The highly nonlinear water entry problems are governed by the Navier-Stokes equations and were solved by a constrained interpolation profile (CIP)-based finite difference method on a fixed Cartesian grid. In the computation, the 3D CIP method was employed for the advection calculations and a pressure-based algorithm was applied for the nonadvection calculations. The solid body and the free surface interfaces were captured by density functions. For the pressure computation, a Poisson-type equation was solved at each time step by using the conjugate gradient iterative method. Validation studies were carried out for a 3D wedge, a cusped body vertically entering calm water, and the oblique entry of a sphere into calm water. The predicted hydrodynamic forces on the wedge, the cusped body, and the sphere were compared with experimental data.
Thermal Modeling of a Railroad Tapered-Roller Bearing Using Finite Element Analysis
Authors: Tarawneh Constantine M. , Fuentes Arturo A. , Kypuros Javier A. , Navarro Lariza A. , Vaipan Andrei G. , Wilson Brent M.
Published: July 2012

In the railroad industry, distressed bearings in service are primarily identified using wayside hot-box detectors (HBDs). Current technology has expanded the role of these detectors to monitor bearings that appear to “warm trend” relative to the average temperatures of the remainder of bearings on the train. Several bearings set-out for trending and classified as nonverified, meaning no discernible damage, revealed that a common feature was discoloration of rollers within a cone (inner race) assembly. Subsequent laboratory experiments were performed to determine a minimum temperature and environment necessary to reproduce these discolorations and concluded that the discoloration is most likely due to roller temperatures greater than 232 °C (450 °F) for periods of at least 4 h. The latter finding sparked several discussions and speculations in the railroad industry as to whether it is possible to have rollers reaching such elevated temperatures without heating the bearing cup (outer race) to a temperature significant enough to trigger the HBDs. With this motivation, and based on previous experimental and analytical work, a thermal finite element analysis (FEA) of a railroad bearing pressed onto an axle was conducted using ALGOR 20.3™. The finite element (FE) model was used to simulate different heating scenarios with the purpose of obtaining the temperatures of internal components of the bearing assembly, as well as the heat generation rates and the bearing cup surface temperature. The results showed that, even though some rollers can reach unsafe operating temperatures, the bearing cup surface temperature does not exhibit levels that would trigger HBD alarms.
Clovis Age Western Stemmed Projectile Points and Human Coprolites at the Paisley Caves
Authors: Jenkins Dennis L. , Davis Loren G. , Stafford Thomas W. , Campos Paula F. , Hockett Bryan , Jones George T. , Cummings Linda Scott , Yost Chad , Connolly Thomas J. , Yohe Robert M. , Gibbons Summer C. , Raghavan Maanasa , Rasmussen Morten , Paijmans Johanna L. A. , Hofreiter Michael , Kemp Brian M. , Barta Jodi Lynn , Monroe Cara , Gilbert M. Thomas P. , Willerslev Eske
Published: July 2012

They Walked Together

Paisley Cave in Oregon provides some of the earliest evidence for humans in North America.

Jenkins
et al.

(p.
223
) provide a wide variety of additional evidence of early human occupation of this site, including a series of radiocarbon ages extending back to nearly 12,500 radiocarbon years ago (about 14,500 calendar years ago). The find includes examples of projectile points representative of the Western Stemmed Tradition dating to about 11,100 radiocarbon years ago. The Western Stemmed Tradition has been thought to have evolved after the dominant Clovis technology, but the find suggests that the two cultures overlapped in time.
Comment on “Plant Species Richness and Ecosystem Multifunctionality in Global Drylands”
Authors: Jucker Tommaso , Coomes David A.
Published: July 2012

Maestre
et al
. (Reports, 13 January 2012, p. 214) reported a general, but weak, positive relationship between plant diversity and ecosystem multifunctionality in global drylands. We show that the strength of this relationship changes consistently along multiple environmental gradients, becoming strongly positive in stressed habitats. This suggests that biodiversity loss may have especially strong consequences in harsh environments.
An Uncommonly Open Approach
Infastructure
The Social Value of Shared Resources

by Brett M. Frischmann

Oxford University Press, New York, 2012. 435 pp. $85, £55. ISBN 9780199895656.
Authors: Schlager Edella
Published: July 2012

Stressing the links between infrastructure and commons, Frischmann explores what drives the demand for the former and how those drivers should affect public policy.
Fragile Delivery to the Genome
Authors: Gottschling Daniel E.
Published: July 2012

A cytoplasmic protein delivers iron-sulfur clusters to nuclear proteins that function in DNA replication and repair.
Similarities Despite Separation

Born Together—Reared Apart: The Landmark Minnesota Twin Study
by Nancy L. Segal

Harvard University Press, Cambridge, MA, 2012. 416 pp. $49.95, £36.95, €45.00. ISBN 9780674055469.
Authors: Boomsma Dorret I.
Published: July 2012

In addition to charting the history of the Minnesota Study of Twins Reared Apart, Segal reviews the project's conclusions and their impact.
An AIDS-Free Generation?
Authors: Abdool Karim Salim S.
Published: July 2012

The HIV pandemic remains a great global health challenge. With an estimated 33.3 million people living with HIV today, is there really hope of achieving the vision of an AIDS-free generation? Optimists argue that strong political will and generous funding are the essential elements. But skeptics point to the deep-seated structural inadequacies in many health care systems, especially in Africa, where the need is greatest. However, both sides agree that a potential combination of therapeutic and prophylactic antiretroviral strategies brings the prospect of HIV control within reach. And this month, the International AIDS Conference in Washington, DC, “Turning the Tide Together,” will attempt to galvanize concerted global action to focus the world's attention on this challenge.
Genes Suggest Three Groups Peopled the New World
Authors: Gibbons Ann
Published: July 2012

The most comprehensive genetic study to date concludes that Native Americans descend from at least three groups of ancestors from Asia, although these groups intermingled extensively once in the New World.
The Many States of HIV in America
Authors: Cohen Jon
Published: July 2012

Treatment as prevention promises to help the infected and dramatically slow the spread of the virus, but the epidemic's changing demographics present myriad challenges in this diverse country.
HIV and the Cell: The Prisoner's Dilemma
Authors: Cohen Jon
Published: July 2012

Josiah Rich has helped Rhode Island create one of the most progressive and effective programs to help HIV-infected people both behind bars and when they're on the outside.
Dancing the Night Away; Keeping HIV at Bay
Authors: Cohen Jon
Published: July 2012

In Baltimore, strip clubs and clubs that stage "house/ball" events popular with African-American men who have sex with men are receiving increased attention from researchers and public health officials.
Developing capable quality improvement leaders
Authors: Kaminski Geraldine M , Britto Maria T , Schoettker Pamela J , Farber Stacey L , Muething Stephen , Kotagal Uma R
Published: July 2012

Background/objective

Cincinnati Children's Hospital Medical Center created the Intermediate Improvement Science Series (I2S2) training course to develop organisational leaders to do improvement, lead improvement and get results on specific projects.

Design methods

Each multidisciplinary class consists of 25–30 participants and 12 in-class training days over 6 months. Instructional methods include lectures, case studies, interactive application exercises and dialogue, participant reports and assigned readings. Participants demonstrate competence in improvement science by completing a project with improvement in outcome and/or process measures. They present on their projects and receive feedback during each session and one-on-one coaching between sessions.

Results

Since 2006, 279 participants in 11 classes have completed the I2S2course. Participant evaluations have consistently rated satisfaction, learning, application, impact and value very high. Large and statistically significant changes were observed in pre-course to post-course self-assessment of knowledge of five quality improvement topics. Approximately 85% of the projects demonstrated measurable improvement. At follow-up, 72% of improvement projects were completed and made a part of everyday operations in the participant's unit or were the focus of continuing improvement work. Many changes were spread to other units or programmes. Most (88%) responding graduates continued to participate in formal quality improvement efforts and many led other improvement projects. Nearly half of the respondents presented their results at one or more professional conference.

Conclusions

Through the I2S2course, the authors are developing improvement leaders, accelerating the shift in the culture from a traditional academic medical centre to an improvement-focused culture, and building cross-silo relationships by developing leaders who understand the organisation as a large system of interdependent subsystems focused on improving health.
Paramedics' non-technical skills: a literature review
Authors: Shields Allan , Flin Rhona
Published: July 2012

Healthcare organisations have started to examine the impact that the human worker has on patient safety. Adopting the Crew Resource Management (CRM) approach, used in aviation, the CRM or non-technical skills of anaesthetists, surgeons, scrub practitioners and emergency physicians have recently been identified to assist in their training and assessment. Paramedics are exposed to dynamic and dangerous situations where patients have to be managed, often with life-threatening injuries or illness. As in other safety-critical domains, the technical skills of paramedics are complemented by effective non-technical skills. The aim of this paper was to review the literature on the non-technical (social and cognitive) skills used by paramedics. This review was undertaken as part of a task analysis to identify the non-technical skills used by paramedics. Of the seven papers reviewed, the results have shown very little research on this topic and so reveal a gap in the understanding of paramedic non-technical skills.
Fragility fracture risk in cirrhosis: a comparison of the fracture risk assessment tool, British Society of Gastroenterology and National Institute for Health and Clinical Excellence guidelines
Authors: Ayres Lachlan Richard Owen , Clarke Shane , Digby-Bell Jonathan , Dhanda Ashwin Deep , Dharmasiri Suranga , Caddick Katharine , Collins Peter Lesley
Published: July 2012

Objective

Low bone mineral density (BMD) is common in chronic liver disease and predisposes to fracture. We aimed to compare British Society of Gastroenterology (BSG) and National Institute for Health and Clinical Excellence (NICE) osteoporosis guidelines with the fracture risk assessment tool (FRAX). FRAX is a web-based algorithm used to estimate fracture risk with or without dual-emission x-ray absorptiometry (DXA). Pre-BMD FRAX categorises patients to low, intermediate or high risk according to thresholds set by the National Osteoporosis Guidelines Group (NOGG) and recommends lifestyle advice, DXA or anti-osteoporosis treatment, respectively.

Design

The guidelines were applied to 132 patients with cirrhosis (91% Child–Pugh A). The number that would require DXA and be recommended treatment was determined. Using post-BMD FRAX/NOGG as a reference point, high-risk patients not recommended treatment and low-risk patients treated ‘unnecessarily’ were identified.

Results

BSG guidelines were applicable to 100% of the cohort, 88% required DXA and 30% would be recommended treatment. Equivalent figures for NICE guidelines were 30%, 17% and 12%, and for FRAX/NOGG guidelines were 78%, 27% and 15%, respectively. Using BSG guidance 8% of high-risk patients were not recommended treatment and 62% of those treated were low risk, compared with NICE: 3%, 60% and FRAX/NOGG: 13%, 40%, respectively.

Conclusion

For patients with Child–Pugh A cirrhosis BSG guidelines are the most inclusive, but have high cost implications in terms of DXA scanning and unnecessary treatment. Risk stratification using FRAX requires fewer DXA scans with minimal impact in terms of missing high-risk patients, and yields a modest reduction in unnecessary treatment.
Diagnostic and prognostic relevance of Cullin1 expression in invasive ductal carcinoma of the breast
Authors: Min Kyueng-Whan , Kim Dong-Hoon , Do Sung-Im , Sohn Jin Hee , Chae Seoung Wan , Pyo Jung-Soo , Park Chan Heun , Oh Young-Ha , Jang Ki-Seok , Kim Hack-Lyoung , Kim Min
Published: July 2012

Background

Cullin1 (Cul1) is a matrix degrading enzyme known to be involved in the remodelling of extracellular matrix proteins. This enzyme has recently been reported to play a key role in tumour progression and its presence is associated with poor clinical outcome for several different types of tumours.

Methods

159 patients diagnosed with invasive ductal carcinoma between 2000 and 2005 were studied. Cul1 expression was analysed by immunohistochemical staining on a tissue microarray. The relationship between Cul1 expression and clinicopathological parameters was evaluated.

Results

Tumour expression of Cul1 was correlated with prognostic factors such as high histological grade and p53 expression, and was also linked to negative ER and positive HER2 as therapeutic markers (all p<0.05). There was a significant association between poor overall survival and high Cul1 expression in both univariate and multivariate analyses (all p<0.05).

Conclusions

Cul1 expression was significantly associated with high-grade tumours and poor prognosis, suggesting that it may play a role in breast tumour progression. Cul1 expression may therefore be crucial for the prediction of disease outcome in breast cancer patients.
Electrochemical immunoassay of carcinoembryonic antigen based on TiO2–graphene / thionine / gold nanoparticles composite
Authors: Huang Ke-Jing , Wu Zhi-Wei , Wu Ying-Ying , Liu Yan-Ming
Published: July 2012

A novel multilayer film based on gold nanoparticles (AuNPs), thionine (Thi), and TiO2–graphene (TiO2–Gr) was exploited to develop a highly sensitive amperometric immunosensor for detecting carcinoembryonic antigen (CEA). Firstly, Nafion–TiO2–Gr homogeneous composite was dropped on the surface of a glassy carbon electrode (GCE). Then Thi was chemisorbed by the TiO2–Gr–Nafion composite. Furthermore, the negative ly charged AuNPs were chemisorbed onto Thi film through the electrostatic force with the amino groups of Thi. Cyclic voltammetry (CV) was employed to characterize the assembly process and the performance of the immunosensor. Because of the synergistic effect of the AuNPs, Thi, and the unique properties of TiO2–Gr, the obtained immunosensor exhibited a wide linear response to CEA in two ranges from 0.1 to 10.0 ng mL−1 and from 10.0 to 120.0 ng mL−1 with a relatively low detection limit of 0.01 ng mL−1 (S/N = 3), as well as good stability and repeatability.
Time Series Measurement of Electric Field and Electrical Space Charge Distributions in a Dielectric Liquid
Authors: Ihori Haruo , Nakao Hayato , Fujii Masaharu
Published: July 2012

It is important to obtain information about electric field and space charge distributions. We have investigated the measurement of electric field vector distributions in liquid dielectrics using an original method. We developed an optical system to measure electric field distributions on the order of milliseconds. Therefore, time series measurement of electric field distributions in a parallel plane electrode system was carried out. From the obtained field distributions, the time variation of a space charge density distribution was obtained. This is the first example in which the space charge distribution was measured at time intervals of 1 ms.
Diode-Pumped Actively Q-Switched Nd:Lu0.1Y0.9VO4 Laser at 1.34 µm
Authors: Zhao Yongguang , Wang Zhengping , Yu Haohai , Guo Lei , Chen Lijuan , Zhuang Shidong , Sun Xun , Xu Xinguang
Published: July 2012

The continuous-wave (CW) and acoustooptic (AO) Q-switched 1.34 µm laser performance of Nd:Lu0.1Y0.9VO4 crystals was demonstrated. In all operations, an a-cut crystal behaved better than a c-cut crystal. With a T = 3.9% output coupler, the maximum CW output power was 2 W, which corresponded to an optical conversion efficiency of 30.8%. At a pulse repetition frequency (PRF) of 5 kHz, the shortest pulse width, largest pulse energy, and highest peak power were 23.8 ns, 124 µJ, and 5.21 kW, respectively. As we have known, these are the best results obtained for a 1.34 µm pulsed laser based on mixed vanadate crystals.
Enhanced Thermoelectric Performance of a Chimney-Ladder (Mn1-xCrx)Siγ (γ∼1.7) Solid Solution
Authors: Kikuchi Yuta , Miyazaki Yuzuru , Saito Yoshitsugu , Hayashi Kei , Yubuta Kunio , Kajitani Tsuyoshi
Published: July 2012

A partially Cr-substituted solid solution of a higher manganese silicide, (Mn1-x
Cr
x
)Siγ, has been prepared by an arc-melting method and a subsequent annealing process. The compound consists of two tetragonal subsystems of [Mn1-x
Cr
x
] and [Si] with an irrational c-axis ratio, γ= c
Mn/c
Si. According to Vegard's rule, the solubility limit of Cr is determined at x = 0.20. With increasing Cr content x from 0 to 0.20, equivalent to increasing the hole carrier concentration, the a- and c
Mn-axis lengths linearly increase, while the c
Si-axis length gradually decreases. As expected from a valence electron counting rule, the electrical conductivity of (Mn1-x
Cr
x
)Siγ increases with increasing x from 334 S·cm-1 (x = 0) to 727 S·cm-1 (x = 0.20) at room temperature. The Cr-substituted samples undergo a microscale domain separation; the sample with a nominal composition of x = 0.20 consists of Cr-rich (x∼0.3) and Mn-rich (x∼0.1) dendritic domains with a typical size of ∼100 µm. Despite the substantial increase in electrical conductivity, the total thermal conductivity decreases with increasing x owing to a marked reduction in lattice contribution. As a consequence, the dimensionless figure-of-merit ZT increases from 0.28 (x = 0) at 800 K to 0.45 (x = 0.20) at 900 K.
Effects of Nb Surface and Ti Interface Layers on Thermal Stability and Electrical Resistivity of Ag Thin Films
Authors: Zhang Ziyang , Kawamura Midori , Abe Yoshio , Kim Kyung Ho
Published: July 2012

Nb/Ag, Ag/Ti, and Nb/Ag/Ti films were prepared by rf magnetron sputtering to investigate the effects of the Nb surface and Ti interface layers on the thermal stability and electrical resistivity of 100-nm-thick Ag thin films. The Nb surface layer, regardless of the chemical state of metal or oxide, prevented the migration of Ag atoms during annealing, which contributed to the agglomeration suppression of Ag films. Ti interface layers not only improved the adhesion of Ag films to SiO2 substrates but also impelled the overcoated Ag atoms to arrange along the close-packed plane (111); thus, Ag/Ti films exhibited relatively good thermal stability and low resistivity. By combining the roles of the Nb surface and Ti interface layers, Nb (5 nm)/Ag (100 nm)/Ti (3 nm) films showed the highest thermal stability and the lowest resistivity. Different materials of surface and interface layers might be more effective for improving the thermal stability and electrical resistivity of Ag films.
Analytical models for trust based routing protocols in wireless ad hoc networks
Authors: Kukreja Deepika , Singh Umang , Reddy B. V.R.
Published: July 2012

In Wireless Ad Hoc Network environment, there are three ways to understand a routing protocol: (i) monitoring, (ii) simulation and (iii) modeling. In this paper, the different trust based secure routing protocols used in wireless ad hoc networks are analyzed, modeled and described by incorporating process flow diagrams. These process flow diagrams represent stepwise work flow activities and actions. It shows the overall flow of control of a process, program or a protocol. This paper focuses on the security aspects of routing by incorporating trust parameter into account and also highlights methodology used in secure routing protocols. Such protocols have been categorized based on the model used for enforcing security, methodology and information for making effective routing decisions. In this paper, we model, discuss and analyze trust based secure ad hoc routing schemes which do not require each network node to work in promiscuous mode. We propose and design a new protocol - Trust based Routing using Dominating Set Approach (TRDSA) which overcomes the shortcomings of existing protocols.
Time properties dedicated transformation from UML-MARTE activity to time transition system
Authors: Ge Ning , Pantel Marc , Crégut Xavier
Published: July 2012

Critical Real-Time Systems (RTS) have strong requirements concerning system's reliability. UML and its profile MARTE are standardized modeling languages widely accepted by industrial designers to cope with the development of complex RTS. Relying on Model-Driven Engineering (MDE), time properties verification of UML-MARTE specifications at early phases of the system lifecycle becomes possible. A key issue is to eliminate the gap between UML semi-formal semantics and fully formal executable semantics using model transformation. The model transformation must guarantee the consistency between high-level user models and lowerlevel verification models. Meanwhile, it should guarantee that the subsequent verification is not too expensive and can be applied to real size industrial models. This paper presents an approach to translate UML-MARTE Activity Diagrams into Time Transition System (TTS) with the aim of efficiently verifying time properties in RTS. TTS is a generalization of Time Petri Nets (TPN) with the priority and data handling at the transition level, supported by TINA model checker. This contribution focuses on how to define the TTS formal semantics to avoid the core problem of state space explosion in model checking. This work has been integrated in a time properties verification framework for UML-MARTE RTS specifications. The proposed method is evaluated using a representative case study. Experimental results are given to demonstrate the method's performance.
A logic-based semantics for the verification of multi-diagram UML models
Authors: Baresi Luciano , Morzenti Angelo , Motta Alfredo , Rossi Matteo
Published: July 2012

UML is a well-known and widely used design notation: it offers a rich set of modeling elements, but their behavior is often not properly defined. Many proposals have tried to provide UML with a formal semantics, but they often focus on a limited number of diagram types, and thus do not provide a viable solution for the actual verification of complex UML models. This paper addresses a significant and consistent set of UML diagrams, called MADES UML, and uses a metric temporal logic to ascribe a formal semantics to them. It also introduces a prototype verification tool based on a bounded model/satis ability checker. The verification of a car collision avoidance system gave encouraging results.
Refinement patterns for ASTD
Authors: Milhau Jérémy , Gervais Frédéric , Laleau Régine , Frappier Marc
Published: July 2012

astd is a formal and graphical language specifically defined for information system specification. Up to now, a specifier had to build an astd specification from scratch and there were no refinement techniques for stepwise construction. This paper aims at introducing refinement patterns for astd, which are inspired from real case studies. For each pattern, proof obligations have been identified to define the refinement semantics we want to provide. The three refinement patterns presented in the paper are illustrated by an example of a basic complaint management system.
Energy efficient scheduling of HPC-jobs on virtualize clusters using host and VM dynamic configuration
Authors: Takouna Ibrahim , Dawoud Wesam , Meinel Christoph
Published: July 2012

Energy efficient resource management has become a significant concern in virtualized data centers to reduce operational costs and extend systems' lifetime. The opportunity of reducing energy can be achieved by using Dynamic Voltage Frequency Scaling (DVFS) and hosts consolidation.However, energy management of emerging High Performance Computing (HPC) clouds that host CPU-intensive jobs is more challenging. In this work, we present an optimization solution to assuage the trade-offs between energy and acceptance ratio of jobs. To achieve this, we consider the current multicore processor architecture, which supports DVFS scheme. Furthermore, we tailored an energy model for multicore processor based on the number of active cores, the average running frequency, and memory. A power-aware local VM scheduler is also implemented at the host level. Importantly, we show the importance of including static power in the energy model. Finally, we compared our approach with pure DVFS and DVFS with live migration. The results show that our approach outperforms the other approaches in terms of energy, SLA violation percentage, system utilization, and number of finished jobs. As a future work, we will implement this in a heterogeneous cluster and will consider the cost of turning off and on the hosts.
mTags
Authors: de Oliveira Augusto Born , Saif Ur Rehman Ahmad , Fischmeister Sebastian
Published: July 2012

In this work we propose mTags, an efficient mechanism that augments microkernel interprocess messages with lightweight metadata to enable the development of new, system-wide functionality without requiring modification of the application source code. As such it is well suited for systems with a large legacy code base or third-party applications like phone and tablet applications.

We explored mTags in a variety of different contexts in local and distributed system scenarios. For example, we detail use cases in areas including messaging-induced deadlocks and mode propagation. To demonstrate that mTags is technically feasible and practical, we implemented it in a commercial microkernel and executed multiple sets of standard benchmarks on two different computing architectures. The results clearly demonstrate that mTags has only negligible overhead and strong potential for many applications.
Experiences in teaching an educational user-level operating systems implementation project
Authors: Aviv Adam J. , Mannino Vin , Owlarn Thanat , Shannin Seth , Xu Kevin , Loo Boon Thau
Published: July 2012

The importance of a comprehensive implementation component for undergraduate Operating Systems (OS) courses cannot be understated. Students not only develop deep insight and understanding of OS fundamentals, but they also learn key software engineering skills that only a large development project, such as implementing an OS, can teach. There are clear benefits to traditional OS projects where students program or alter real (Linux) kernel source or extend educational OS implementations; however, in our experience, bootstrapping such a project is a huge undertaking that may not be accessible in many classrooms. In this paper, we describe a different approach to the OS implementation assignment: A user-level Operating System simulation based on UNIX preemptive signaling and threading constructs called ucontext. We believe that this variation of the implementation assignment provides many of the same educational benefits as traditional low-level projects without many of the expensive start-up costs. This project has been taught for a number of years at the University of Pennsylvania and was recently overhauled for the Fall 2011 semester. This paper describes the current version of the project and our experiences teaching it to a class of 54 students.
Esophageal wall blood perfusion during contraction and transient lower esophageal sphincter relaxation in humans
Authors: Jiang Yanfen , Bhargava Valmik , Kim Young Sun , Mittal Ravinder K.
Published: July 2012

We recently reported that esophageal contraction reduces esophageal wall perfusion in an animal study. Our aim was to determine esophageal wall blood perfusion (EWBP) during esophageal contraction and transient lower esophageal sphincter relaxations (TLESRs) in humans. We studied 12 healthy volunteers. A custom-designed laser Doppler probe was anchored to the esophageal wall, 4–6 cm above the LES, by use of the Bravo pH system so that the laser light beam stay directed toward the esophageal mucosa. A high-resolution manometry equipped with impedance electrodes recorded esophageal pressures and reflux events. Synchronized pressure, impedance, pH, and EWBP recordings were obtained during dry and wet swallows and following a meal. Stable recordings of laser Doppler EWBP were only recorded when the laser Doppler probe was firmly anchored to the esophageal wall. Esophageal contractions induced by dry and wet swallows resulted in 46 ± 9% and 60 ± 10% reduction in the EWBP, respectively (compared to baseline). Reduction in EWBP was directly related to the amplitude (curvilinear fit) and duration of esophageal contraction. Atropine reduced the esophageal contraction amplitude and decreased the EWBP reduction associated with esophageal contraction. TLESRs were also associated with reduction in the EWBP, albeit of smaller amplitude (29 ± 3%) but longer duration (19 ± 2 s) compared with swallow-induced esophageal contractions. We report 1) an innovative technique to record EWBP for extended time periods in humans and 2) contraction of circular and longitudinal muscle during peristalsis and selective longitudinal muscle contraction during TLESR causes reduction in the EWBP; 3) using our innovative technique, future studies may determine whether esophageal wall ischemia is the cause of esophageal pain/heartburn.
Can Biofluids Metabolic Profiling Help to Improve Healthcare during Pregnancy?
Authors: Graça Gonçalo , Diaz Sílvia O. , Pinto Joana , Barros António S. , Duarte Iola F. , Goodfellow Brian J. , Galhano Eulália , Pita Cristina , Almeida Maria do Céu , Carreira Isabel M. , Gil Ana M.
Published: July 2012

This paper describes a metabonomics study of 2nd trimester biofluids (amniotic fluid, maternal urine, and blood plasma), in an attempt to correlate biofluid metabolic changes with suspected/diagnosed fetal malformations (FM) and chromosomal disorders as well as with later occurring gestational diabetes mellitus (GDM), preterm delivery (PTD), and premature rupture of membranes (PROM). The global biochemical picture given by the threesome of biofluids should enable the definition of potential disease signatures and unveil potential metabolite markers for clinical use in predictive prenatal diagnostics. Results show that relatively strong metabolic disturbances accompany FM, reflected in all three biofluids and thus suggesting the involvement of both fetal and maternal metabolisms. Regarding GDM, amniotic fluid and maternal urine seem potential good media to detect early metabolic changes, and PTD subjects show small metabolite changes in the same biofluids, undergoing work being focused on plasma composition. Chromosomal disorders show an interestingly marked effect on maternal urine, whereas no statistically relevant early changes have been observed for PROM subjects. Interestingly, in the case of FM and chromosomal disorders, maternal biofluids show some sensitivity to disorder type, for example, for central nervous system malformations and trisomy 21, respectively. These results show the usefulness of biofluid metabonomics to probe overall metabolic disturbances in relation to prenatal disorders.
Physical Activity among Veterans and Nonveterans with Diabetes
Authors: Bouldin Erin D. , Reiber Gayle E.
Published: July 2012

Engaging in regular physical activity (PA), with or without a corresponding decrease in weight, is associated with improved health outcomes. The purpose of this study was to quantify the extent to which PA differed between veterans and nonveterans and to determine how diabetes and age influenced this association. Data from the 2009 Behavioral Risk Factor Surveillance System were used in this study. Respondents were classified as having diabetes if they reported ever being diagnosed with diabetes except during pregnancy. Respondents who reported ever serving on active military duty were classified as veterans. Based on self-report, we calculated the average minutes per week of moderate, vigorous, and total activity. After adjusting for sex, race and ethnicity, household income, education level, body mass index (BMI), and recent health checkup, veteran status was associated with a small but significantly larger amount of average weekly moderate PA (2.2 minutes,P=0.0058) but not average weekly vigorous PA (−0.02 minutes,P=0.98). Diabetes and prediabetes were associated with significantly lower mean levels of both moderate and vigorous intensity PA, as was increasing age. Consistent with prior research, veterans engaged in more PA than nonveterans. The association between diabetes, age, and physical activity did not differ by veteran status.
Existence of Periodic Solutions for a Class of Difference Systems with p‐Laplacian
Authors: Chen Kai , Zhang Qiongfen
Published: July 2012

By applying the least action principle and minimax methods in critical point theory, we prove the existence of periodic solutions for a class of difference systems with p‐Laplacian and obtain some existence theorems.
Protein‐Ligand Interactions of the D‐Galactose/D‐Glucose‐Binding Protein as a Potential Sensing Probe of Glucose Biosensors
Authors: Stepanenko Olga V. , Stepanenko Olesya V. , Fonin Alexander V. , Verkhusha Vladislav V. , Kuznetsova Irina M. , Turoverov Konstantin K.
Published: July 2012

In this paper we have studied peculiarities of protein‐ligand interaction under different conditions. We have shown that guanidine hydrochloride (GdnHCI) unfolding‐refolding of GGBP in the presence of glucose (Glc) is reversible, but the equilibrium curves of complex refolding‐unfolding have been attained only after 10‐day incubation of GGBP/Glc in the presence of GdnHCl. This effect has not been revealed at heat‐induced GGBP/Glc denaturation. Slow equilibration between the native protein in GGBP/Glc complex and the unfolded state of protein in the GdnHCl presence is connected with increased viscosity of solution at moderate and high GdnHCl concentrations which interferes with diffusion of glucose molecules. Thus, the limiting step of the unfolding‐refolding process of the complex GGBP/Glc is the disruption/tuning of the configuration fit between the protein in the native state and the ligand.
Reactivity of Phenol Allylation Using Phase-Transfer Catalysis in Ion-Exchange Membrane Reactor
Authors: Wu Ho Shing , Fu Yeng Shing
Published: July 2012

This study investigates the reactivity of phenol allylation using quaternary ammonium salt as a phase-transfer catalyst in three types of membrane reactors. Optimum reactivity and turnover of phenol allylation were obtained using a respond surface methodology. The contact angle, water content, and degree of crosslinkage were measured to understand the microenvironment in the ion exchange membrane.
Interaction between Nonhistone Protein HMGB1 and Linker Histone H1 Facilitates the Formation of Structurally Ordered DNA‐Protein Complexes
Authors: Polyanichko Alexander , Chikhirzhina Elena
Published: July 2012

The structural organization of the DNA complexes with nonhistone chromosomal protein and linker histone H1 was studied using circular dichroism spectroscopy (CD) and atomic force microscopy (AFM). It has been shown that due to the interaction between HMGB1 and H1 highly ordered DNA‐protein complexes emerge in the solution. Their spectral properties are found to be similar to those of DNA/HMGB1‐(AB) complexes, reported earlier. AFM images reveal the formation of fibril‐like structures in the solution. We suggest that the electrostatic screening of the HMGB1 C‐terminal domain by histone H1 facilitates stronger interaction of the HMGB1/H1 with DNA and the formation of the ordered supramolecular DNA‐protein complexes.
Specific Far Infrared Spectroscopic Properties of Phospholipids
Authors: Hielscher Ruth , Hellwig Petra
Published: July 2012

We describe the specific spectral signature of different phospholipids and sphingolipids in the far infrared. Three specific spectral domains have been found: the head group contributions (600 and 480 cm−1); the modes of the torsion motion of the hydrocarbon chains and of the skeleton vibration (460 to 180 cm−1); and the hydrogen‐bonding continuum (below 300 cm−1). Marker bands for individual phospholipids are distinguished.
SERS Microspectroscopy of Biomolecules on Dried Ag Colloidal Drops
Authors: Šimáková P. , Procházka M. , Kočišová E.
Published: July 2012

We report the application of dried Ag hydroxylamine‐reduced colloidal drops to surface‐enhanced (resonance) Raman scattering (SE(R)RS) study of biomolecules using Raman microspectroscopy. 5,10,15,20‐tetrakis(1‐methyl‐4‐pyridyl)porphyrin (TMPyP), amino acid tryptophan, and phospholipid 1,2‐distearoyl‐sn‐glycero‐3‐phosphocholine (DSPC) served as testing biomolecules. Ag colloid/biomolecule drop dried on glass support forms a ring in the edge part of the drop in which almost all nanoparticles are clustered. This specific drying process promotes adsorption of the studied biomolecules in highly enhancing sites (“hot spots”) as well as concentrates them in the ring. We were able to obtain SE(R)RS spectra from the ring that cannot be acquired directly from Ag colloidal solutions (SERRS spectrum of 1 × 10−10 M TMPyP by 1 s accumulation time, SERS spectrum of 2 × 10−7 M DSPC). Despite the spectral irreproducibility and problems with spurious bands in some cases, SERS microspectroscopy of studied biomolecules using dried Ag colloid/adsorbate systems improves SERS applicability and sensitivity in comparison to measurements directly from Ag colloidal solution.