bluuebunny/crossref_metadata_2025 huggingface dataset:
A Meta-Analysis of Studies on Protection Motivation Theory and Information Security Behaviour
Authors: Sommestad Teodor , Karlzén Henrik , Hallberg Jonas
Published: February 2016

Individuals' willingness to take security precautions is imperative to their own information security and the information security of the organizations they work within. This paper presents a meta-analysis of the protection motivation theory (PMT) to assess how its efficacy is influenced by the information security behavior it is applied to. It investigates if the PMT explains information security behavior better if: 1) The behavior is voluntary? 2) The threat and coping method is concrete or specific? 3) The information security threat is directed to the person itself? Synthesized data from 28 surveys suggests that the answers to all three questions are yes. Weighted mean correlation coefficients are on average 0.03 higher for voluntary behavior than mandatory behavior, 0.05 higher for specific behaviors than studies of general behaviors, 0.08 higher to threat appraisal when the threat targets the individual person instead of the person's organization or someone else.
A Survey and Surveillance Issues in Smart Homes Environment for Assistive Living
Authors: Patrick Ryan , Bourbakis Nikolaos
Published: February 2016

A surveillance system for assisting the elderly in remaining independent in their familiar environment is one of the subjects interest in recent healthcare studies. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, alert family members or healthcare professionals to abnormal behaviors. This paper addresses the early stages and issues of the development of such a system, the physical characteristics of the system that is being designed, early results, and guidance on the future work that will have to be completed in the future.
Profile-Based Text Classification for Children with Dyslexia
Authors: Litsas Chris , Mastropavlou Maria , Symvonis Antonios
Published: February 2016

Although extensive research has been conducted in the field of text-readability and user modelling, scholars and researchers have taken into consideration only linguistic complexity in order to classify a text as readable or not. In this paper, the authors move one step forward by considering one more factor, namely intended reader's skills, and by trying to study text readability from a user-specific perspective. Central to our approach is the notion of the user's profile which carries information regarding the linguistic difficulties a user with dyslexia may experience. Based on the user's profile, they develop heuristics for evaluating text's readability for the specific user. The developed heuristics are incorporated in the text classification services of the iLearnRW project, aiming to facilitate the selection of appropriate/suitable reading resources, written in English or Greek, for children with dyslexia1.
Scope Reductions as Tool for Cost Control in Construction Projects
Authors: Olsson Nils O. E.
Published: February 2016

Scope management is a key issue in construction projects. This paper studies scope reductions. Potential reductions of project scope as well as budget contingencies have been a tool for cost control of governmental investments in Norway since 2001. This paper studies implementation of such reduction in major construction projects in different governmental sectors. Project representatives were contacted to obtain information about actual use of pre-defined potential scope reductions. Eight of the 14 studied projects did not implement any of the predefined reductions. Six projects implemented some of the reductions. These reductions were mainly general reductions of the quality of the facilities. The Norwegian reduction lists are based on an unusually high degree of specification of potential actions for cost control. International best practice is more concerned with general approaches. To function as intended, possible reductions should be possible to implement late in a project. General contingencies appear to be more effective for cost control than predefined scope reductions.
Risk and Models of Innovation Hubs
Authors: Baydoun Mohammad
Published: February 2016

The purpose of this article is to compare two innovation hubs with two different models each of which was able to foster innovation in its context and understand impact of these models on risk in innovation research. They both closed the distance between academia and industries through establishing partnerships with these industries in order to find solutions for their problems through practical research. These two innovation hubs are Massachusetts Institute of Technology and Fraunhofer Society for the Advancement of Applied Research. Analysis of these two successful case studies shall help in revealing learned lessons that could benefit other research institutions in the future.
Outlining the Issues of Cloud Computing and Sustainability Opportunities and Risks in European Organizations
Authors: Isaias Pedro , Issa Tomayess , Chang Vanessa , Issa Theodora
Published: February 2016

Cloud computing and sustainability have become part of a core strategy in organizations globally and locally, since their characteristics assist both businesses and individuals to become unique and exclusive in their work and study. Businesses and individuals should integrate sustainability in their strategy and to include cloud computing technology as a tool for sustainable work, especially in the Information Technology (IT) departments to cut costs and increase efficiencies and productivity. This paper examines European organizations' awareness of cloud computing and sustainability opportunities and risks, via an online survey targeting 56 Information Technology managers in Europe. A Cloud Computing Conceptual model was developed using structural equation modeling (SEM) to evaluate the survey results. The study results confirmed that cloud computing technology opportunities, including sustainability in the organization's strategy, will enhance their job performance and job satisfaction, use and awareness; however, security, privacy and risks are still a major concern.
Online Store Loyalty
Authors: Mpinganjira Mercy
Published: February 2016

This paper investigates drivers and outcomes of online-store loyalty. Data was collected from 201 online shoppers in Gauteng, South Africa using a structured questionnaire. The findings show that perceived value, trust and perceived web-usability are important factors that drive online store loyalty. Trust was found to be significantly influenced by perceived expertise in order fulfilment. The results also show that online store loyalty exerts positive influence both on customers' sensitivity to price as reflected by willingness to pay more and on word-of-mouth. The findings point to the need for online store managers to pay attention to the identified drivers of online store loyalty if they are to derive its associated benefits.
Utilising Modified UTAUT to Understand Students' Online Shopping Behaviour
Authors: Hassan Shahizan , Rashid Rashdan , Li Feng
Published: February 2016

This study determines the impact of UTAUT on online shopping behavior among polytechnic students. It also studies the significance of self-efficacy and anxiety on the students' behavioral intention of using e-retail website. It provides an empirical test of three forms of self-efficacy and anxiety towards behavioral intention to shop online. The research subjects were 91,830 polytechnic students from 33 polytechnics in Malaysia. The sampling procedure employed is a multi-stage cluster probability sampling. The questionnaires were distributed to 500 students at five polytechnics. Seven hypotheses were tested during data analysis. Performance expectancy, effort expectancy, social influence, self-efficacy, internet self-efficacy, computer self-efficacy and online shopping self-efficacy were found to have strong significant relationship with behavioral intention. While facilitating condition shows a significant relationship towards user acceptance, internet anxiety and online shopping anxiety have a weak significant relationship towards behavioral intention.
A New Compacting Non-Contiguous Processor Allocation Algorithm for 2D Mesh Multicomputers
Authors: Bani-Mohammad Saad , Ababneh Ismail M. , Yassen Mohammad
Published: February 2016

In non-contiguous allocation, a job request can be split into smaller parts that are allocated possibly non-adjacent free sub-meshes rather than always waiting until a single sub-mesh of the requested size and shape is available. Lifting the contiguity condition is expected to reduce processor fragmentation and increase system utilization. However, the distances traversed by messages can be long, and as a result the communication overhead, especially contention, is likely to increase. The extra communication overhead depends on how the allocation request is partitioned and assigned to free sub-meshes. In this paper, a new non-contiguous processor allocation strategy, referred to as Compacting Non-Contiguous Processor Allocation Strategy (CNCPA), is suggested for the 2D mesh multicomputers. In the proposed strategy, a job is compacted into free locations. The selection of the free locations has for goal leaving large free sub-meshes in the system. To evaluate the performance improvement achieved by the proposed strategy and compare it against well-known existing non-contiguous allocation strategies, the authors conducted extensive simulation experiments. The results show that the proposed strategy can improve performance in terms of job turnaround times and system utilization.
A New Error Compensation Method for a Four-Axis Horizontal Machine Tool
Authors: Li Yang , Zhao Ji , Ji Shi Jun , Wang Xin
Published: February 2016

A new method compensating geometric error components of a four-axis horizontal machine tool is presented in this paper. Homogeneous transformation matrices (HTMS) and error conversion are integrated in the compensation strategy. A mathematical model which contains 29 geometric error components is established based on HTMS and the errors in X, Y and Z directions are obtained through calculation. The errors in three directions are compensated by shifting the corresponding axis. But the configuration of this machine tool is X-axis, Z-axis, B-axis, C-axis without Y-axis, so the errors in X, Y and Z directions need to be converted into X, Z and C directions which is different from the traditional machine tools. The errors after conversion are used to compensation directly. This approach is significant for the error modeling and compensation which is an easy and efficient way to improve the precision of the four-axis machine tools.
Orthogonal Experiment Study of Micro/Nano Motion Platform
Authors: Zhao Rong Li , Chen Xin , Li Ke Tian
Published: February 2016

This paper introduced a kind of micro/nanomotion platform. The platform mainly includes 12 flexible hinges, piezoelectric ceramic driver (PZT), motion platform (loaded platform), pre-tightening force adjusting screw and so on. The orthogonal experiment method was used to the output displacement of the micro/nanoplatform. The relationship among the voltage, pre-tightening force and output displacement of the platform was analyzed. The factor level table of the output displacement was produced. The experimental system was established by Laser interferometer and pressure sensor, then the output displacement was obtained when the voltage ranges from 0V to 150V on the condition of every force (20N, 40N, 60N, 80N and 100N). The experimental result lays the foundation for the regression analysis of the output displacement of the platform.
The Analysis and Design of a Large Stroke with High-Precision Polarized Laser Interferometer System
Authors: Wu Wan Duo , Huang Qiang Xian , Wang Chao Qun , Wu Ting Ting , Xie Hong
Published: February 2016

The technique utilizing single-frequency laser interferometry has very high measurement accuracy, but it has rigorous requirements for optical design which is affected by many factors. In order to achieve single-frequency laser interferometry with large stroke and high precision, the integral layout, the polarization phase shifting technique and the common mode rejection method are adopted to design the length interferometry system. This paper analyzes factors and design requirements which affect measurement accuracy with large stroke. Based on polarization phase shifting technique, the system employs the four-beam-signal detection technique and the common mode rejection method, to make a differential processing of four mutually orthogonal signals. Thus, the influences of zero-drift of intensity and environmental change on system are reduced. Combined with a 200 phase subdivision, the system achieves the resolution with 0.8 nm. Under the VC++ environment, the displacement measurement results are compensated and corrected according to the environmental parameters. Compared with the Renishaw XL-80 laser interferometer, the system has better stability in short term. In the measuring range of 60 mm, the effectiveness of the system is verified.
Fabrication of Micro V-Grooves in Ultra-Precision Grinding
Authors: Lin Ze Qin , Wang Su Juan , Chen Xin Du
Published: February 2016

Ultra-precision grinding is an effective method to machine the optical micro v-groove, which is one of microstructures applied to the fiber-optics connectors, displays and other photonics devices. The ultra-precision grinding technology directly obtains high surface quality for brittle materials when the grinding process is under the ductile mode. This paper introduces general aspects of ultra-precision grinding technology in the fabrication of the micro v-grooves structures and introduces the essential features of ultra-precision grinding. The process of the manufacturing of the optical micro v-grooves components is presented in this paper. It contains the prediction models of surface roughness and form accuracy in the ultra-precision grinding and the optimization model under the consideration of the influences of grinding parameters,grinder factors and the material properties on the surface quality and machining efficiency. This study therefore contributes to providing a further understanding on the mechanisms of material removal and surface generation in ultra-precision girnding.
Using Collins Formula with Scaling Factor to Analysis the Propagation Properties in Laser Focus System Design
Authors: Shi Long , Dong Yu Xing , Lv Ming , Guo Ru Hai
Published: February 2016

A Collins formula method with a scaling factor between the target-and source-plane has been proposed for the laser propagation in the optical system design, which can be used to evaluate the laser optical system performance and the tolerance analysis. The laser propagation in the optical systems can be calculated by the Collins integral formula, and an angular spectrum method has been derived by coordinate substitution. A scaling factor m is introduced to make the choice of the observation-plane more flexibility and the calculation more accurate. The laser optical system has been designed, and its tolerance analysis is conducted by the Angular-Spectrum method. The evaluating criterion is the laser spot radius in the far field, which is defined by 86.5% power in bucket (PIB). The radius of the laser spot in 90m between 0.8mm and 1.4mm with the expectation of 0.92mm is calculated by the tolerance analysis, and the experimental result is 1.01mm. In the distance of 47m, the radius is between 0.42mm and 0.73mm with the expectation of 0.48mm calculated by the tolerance analysis, the experimental result is 0.46mm. The experiment agrees the result of the tolerance analysis well. The focal shift for laser propagation in the optical systems is validated. The experiment results confirm the calculation and it proved the use of the method in laser focus optical system design.
Solution Concentration Affected Wavy Fibers Fabrication via Auxiliary Electrodes in Near-Field Electrospinning
Authors: Zhu Zi Ming , Chen Xin Du , Huang Shen Neng , Fang Fei Yu , Peng Dong Yu , Zeng Jun , Du Ze Feng , Wang Han
Published: February 2016

Wavy fibers, fabricated via electrospinning, have been designed into many applications, such as the sensors, resonators, electromechanical systems, stretchable electronics products, flexible displays. In order to control the wavy fiber morphology, auxiliary electrodes (A-E) have been designed to control the wavy fibers deposition in near-field electrospinning (NFES), and the alternate current supplied to A-E could control fibrous amplitude and the generated frequency of the wavy fibers well. Here continue to study the wavy fiber deposited morphology via A-E in NFES in this paper, the results show that, there are still many factors would affect the fibrous amplitude, and this paper is aimed at find out the regular of the wavy fiber deposition via the A-E, which are meaningful to control wavy fiber morphology well.
Finite Element Simulation about Abrasive Belt Grinding Silicon Carbide
Authors: Ji Shi Jun , Liu Lei Lei , Zhao Ji , Li Jin Chao
Published: February 2016

Silicon carbide, a high-strength material, has a ductile-brittle transition mechanism. In order to establish a reasonable silicon carbide abrasive belt grinding parameters to obtain high precision silicon carbide free-surface efficiently, a series of finite element simulations were conducted to comprehend the single point diamond grinding of silicon carbide using professional analysis software of nonlinear finite element in this paper. According to the differences of cutting parameter, such as cutting depth, cutting deformation of the chip and the maximum cutting force were studied. For the free-form surface with higher accuracy, the data showed that ductile machining of silicon carbide is more efficient along with the larger rake angle, the higher cutting speed and the smaller cutting depth.
From Shape to Feature - A Novel Structural Design Idea for Dynamic Feature Adjustable Micro Motion Stages Based on Tension Stiffening
Authors: Yang Zhi Jun , Chen Xin , Wang Su Juan , Gao Jian , Chen Xin Du
Published: February 2016

Guidance mechanism such as fast tool servo (FTS) is widely used in precision machining, in the current design method, either the analytic solution or topological optimization, the dynamic feature, namely the stiffness, inertial and frequency, are subjected to the shape and sizing of the designed structure, especially sensitive to the geometric feature of flexure hinge, which caused high machining precision and high cost. In this proceeding, a novel structural design idea for guidance mechanism type micro motion stages based on tension stiffening which allow the dynamic feature adjustable is presented. Firstly, the design of micro motion stages is reviewed on both analytic and topological optimization, and the advantage of the two kinds of commonly used flexure type, the notch type and leaf spring type, are compared, and the latter is chosen as an idea type for guidance mechanism for its uniform deformation and none stress concentration. Secondly, tension stiffening using in the stringed instruments is described, in which the length, tension and linear density is discussed to change the pitch (vibration frequency and amplitude) of the stringed instruments. Finally, a novel structural design idea origin from stringed instruments is discussed, with the assumption that the leaf spring type flexure hinge are symmetrical layout on both sides of the micro motion stage, the stiffness and frequency change rate are also discussed. A numerical method is used to show the efficiency of the presented method.
An Investigation on Multi-Nozzle near Field Electrospinning: Experimentation and Simulation
Authors: Huang Shen Neng , Chen Xin Du , Wang Zhi Feng , Zeng Jun , Fang Fei Yu , Wang Han
Published: February 2016

There are massive reports about near-field electrospinning (NFES) in the literature and the NFES has great tendency for scientific and industrial applications. It is important to improve the machining efficiency of electrospinning. Through the study of the multi-nozzle near-field electrospinning, a new method by adjusting the electrode-to-collector distance (E-C-D) is presented in this paper to make sure the jets with a straight line. The method is divided into two steps: (1) to adjust the E-C-D larger to get the jet at each nozzle, (2) to make the E-C-D smaller enough to get straight jets. Moreover, this paper simulates the electric field density which helps to provide a further understanding on the process of NFES. The experimental results contribute to making a better control on the jets in NFES.
Design and Control of a Novel Fast Tool Servo Used in Diamond Turning of Freeform Optics
Authors: Tian Fu Jing , Yin Zi Qiang , Li Sheng Yi
Published: February 2016

Optical free-form surfaces are becoming more and more popular in the industry application, which can be fabricated by diamond turning based on fast tool servo (FTS). It is an efficient, precise and low-cost processing method. In order to use diamond turning to fabricate the freeform optics, this paper develops a novel long range fast tool servo which is actuated by voice coil motor. The total range can reach up to 30 mm. The important parts of the FTS have been simulated and analyzed. The transfer function model identification of the FTS has been accomplished. Since the desired tool trajectories are approximately periodic signals in freeform surfaces turning, and the adaptive feedforward cancellation (AFC) control can achieve perfect tracking and disturbance rejection of periodic signals, the AFC control is designed to be added on the IMC-PID controller.
Characterizations of Removal Rate and Temperature in the Inductively Coupled Plasma Etching of Silicon Carbide
Authors: Li Na , Zhang Peng , Xin Qiang , Jin Jiang , Wang Bo
Published: February 2016

Silicon carbide (SiC) is widely used in terrestrial and space applications because of its good mechanical, thermal and optical properties. Nevertheless, traditional grinding and polishing technologies cannot meet the machining requirements due to the high hardness and brittleness. In this paper, Inductively Coupled Plasma (ICP) is utilized to process the SiC optics. The effects of different processing recipes on the removal rate and temperature are investigated. The results show that the removal rate almost keeps stable with processing time and changes with the flow rate of plasma gas, reaction gas, the ratio of CF4/O2 and the power. The input power and processing time are the two main influence factors on the processing temperature.
An Experimental Investigation of Effect of Process Parameters on Materials Removal Characteristics in Fluid Jet Polishing
Authors: Cao Zhong Chen , Cheung Chi Fai
Published: February 2016

Fluid Jet Polishing (FJP) is a promising ultra-precision machining technology which shows great potential with regard to the application value in the generation of freeform surfaces with sub-micrometre form accuracy and nanometric surface finish. The polishing tool influence function (TIF), which is affected by various parameters and commonly assessed in terms of width, maximum depth and volumetric material removal rate, is critically required for corrective polishing and deterministic machining. In this study, a series of experiments was conducted to study the effect of various process parameters on the polishing tool influence function. The polishing machine used is a Zeeko IRP 200 ultra-precision freeform polishing machine, with three linear axes and three rotational axes. All polishing experiments were performed on BK7, which is one of the most common technical optical glass materials for high-quality optical components in the visible range. These specimens were polished using Al2O3 (Aluminium oxide) abrasive particles and measured by a Zygo Nexview 3D Optical Surface Profiler. All these experiments were conducted by changing one process parameter and keeping the other process parameters constant. In this paper, the experimental results are described in detail to show the relationships between the material removal and the various parameters (i.e. slurry pressure, standoff distance, impingement angle, etc.), and some interesting experimental results are explained.
Preoperative Stabilization of Infants With Hypoplastic Left Heart Syndrome Before Stage I Palliation
Authors: Donnellan Amy , Justice Lindsey
Published: February 2016

Hypoplastic left heart syndrome is a severe form of congenital heart disease that results in single-ventricle physiology. Although surgical palliation in infants with this syndrome is widely agreed on in practice, variation occurs in both surgical and medical management. Perinatal factors that affect preoperative management include the subtype of the syndrome and the patient’s birth weight, gestational age, and genetic abnormalities. The general aspects of perioperative stabilization and management are monitoring, use of vasoactive infusions, ventilatory support, and nutrition. Management strategies for balancing single-ventricle physiology are aimed at addressing the 3 major causes of desaturation: diminished pulmonary blood flow, low mixed venous oxygen saturation, and pulmonary venous desaturation.
Implementing Electronic Tablet-Based Education of Acute Care Patients
Authors: Sawyer Tenita , Nelson Monica J. , McKee Vickie , Bowers Margaret T. , Meggitt Corilin , Baxt Sarah K. , Washington Delphine , Saladino Louise , Lehman E. Philip , Brewer Cheryl , Locke Susan C. , Abernethy Amy , Gilliss Catherine L. , Granger Bradi B.
Published: February 2016

Poor education-related discharge preparedness for patients with heart failure is believed to be a major cause of avoidable rehospitalizations. Technology-based applications offer innovative educational approaches that may improve educational readiness for patients in both inpatient and outpatient settings; however, a number of challenges exist when implementing electronic devices in the clinical setting. Implementation challenges include processes for “on-boarding” staff, mediating risks of cross-contamination with patients’ device use, and selling the value to staff and health system leaders to secure the investment in software, hardware, and system support infrastructure. Strategies to address these challenges are poorly described in the literature. The purpose of this article is to present a staff development program designed to overcome challenges in implementing an electronic, tablet-based education program for patients with heart failure.
Palliative Care in Critical Rural Settings
Authors: Mayer Dorothy “Dale” M. , Winters Charlene A.
Published: February 2016

The United States has 1332 critical access hospitals. These hospitals have fewer than 25 beds each and a mean daily census of 4.2 patients. Critical access hospitals are located in rural areas and provide acute inpatient services, ambulatory care, labor and delivery services, and general surgery. Some, but not all, critical access hospitals offer home care services; a few have palliative care programs. Because of the millions of patients living with serious and life-threatening conditions, the need for palliative care is increasing. As expert generalists, rural nurses are well positioned to provide care close to home for patients of all ages and the patients’ families. A case report illustrates the role that nurses and critical access hospitals play in meeting the need for high-quality palliative care in rural settings. Working together, rural nurses and their urban nursing colleagues can provide palliative care across all health care settings.
Predictors of positive endoscopic findings in hospitalized patients with occult gastrointestinal bleeding
Authors: Sengupta Neil , Tapper Elliot B. , Patwardhan Vilas R. , Lembo Anthony J. , Feuerstein Joseph D.
Published: February 2016

Anemia with occult gastrointestinal bleeding (OGIB) is a common reason for inpatient gastroenterology consultation and endoscopy. However, the utility of inpatient endoscopy in this setting is unclear. The aim of this paper is to determine variables that predict positive endoscopic examinations for inpatients presenting with anemia and OGIB. We performed a prospective observational study of consecutive hospitalized patients between March 2013 and April 2014 with anemia and OGIB. For patients undergoing inpatient endoscopic evaluation, logistic regression was used to determine which variables were associated with detecting etiology of OGIB. An occult bleeding score (OBS) was created using receiver operating characteristics and area under the curve (AUC) analysis to predict detection of bleeding source and need for endoscopic intervention. Of the 74 patients identified, 55 (74%) underwent endoscopic evaluation, of whom 28 patients had a source of OGIB identified. Patients with malignancy (OR 7.25, 95%CI 1.06-144) were more likely to have a bleeding source identified on endoscopy, whereas patients with higher admission hemoglobin levels were less likely to have a detected source (OR 0.62, 95%CI 0.41-0.86). The OBS was constructed by assigning a point each for malignancy and admission hemoglobin <8.2 g/dL. The OBS predicted detection of etiology of bleeding and endoscopic intervention with an AUC of 0.79 and 0.75. The yield of endoscopy in determining a bleeding source in patients with OGIB is significant particularly in patients with malignancy or a low hemoglobin level. A simple score can assist in determining whether inpatient endoscopy is warranted in this population.
Watermelon esophagus: a new visual paradigm
Authors: Cowley Kevin , Jennings H. Whitney , Burski Chad , Passarella Michael
Published: February 2016

A 35-year-old male with no prior medical history presented for evaluation of multi-year history of dysphagia to both solids and liquids. He underwent esophagogastroduodenoscopy revealing linear furrows with ring-like esophagus. Pathology of biopsies showed findings consistent with eosinophilic esophagitis (EoE). This is a newly recognized disease entity with a rapidly increasing prevalence that cannot be entirely accounted for by the increasing awareness in medicine. All patients with clinical suspicion of EoE should undergo esophageal biopsies regardless of endoscopic findings, as normal endoscopy can be seen in up to 17% of cases. Numerous non-specific endoscopic findings have been described, including trachealization, felinization, linear furrows, crepe paper mucosa, and longitudinal shearing. We present a unique and neverbefore seen image of EoE that accentuates the findings that may be seen endoscopically
Is obesity still a coronary risk factor?
Authors: Carlon Roberto , Zanchetta Mario
Published: February 2016

a risk factor for developing coronary artery disease, once coronary artery disease has been established, the correlation of obesity with total mortality, cardiovascular mortality, myocardial infarction, and revascularization is unclear and still remains a matter of debate. The relationship between obesity and mortality in patients with coronary artery disease has so far only been investigated by posthoc analysis of cohort studies, which have produced contradictory results. When a higher percentage body fat has been found to be a strong independent predictor of event-free survival, the phenomenon has been described as an ‘obesity paradox’ or ‘reverse epidemiology’. A recent meta-analysis, appearing in the August 19 issue of Lancet on 250.152 patients with documented coronary artery disease, suggests that after grouping 40 cohort studies with adjusted risks, overweight patients were consistently associated with a better survival and lower cardiovascular events than patients with a low body mass index, whereas obesity was associated with a higher total mortality only in patients with history of coronary artery bypass graft, and severe obesity was associated with a significantly higher cardiovascular mortality but not with an increased risk for total mortality. Far from proving that obesity is harmless, these findings suggest that alternative methods might be required to better characterize individuals who truly have excess body fat and that additional studies with different methods are needed. Moreover, still unknown is the unique contribution of higher muscle-to-fat ratio, which may be merely a surrogate of increased physical fitness. Future research is needed to assess the link between high muscle mass, high body fat and clinical outcomes.
Heart failure with preserved systolic function: prevalence and clinical features in a cohort of patients admitted to internal medicine units. The study PRESYF-HF Tuscany
Authors: Biagi Paolo , Abate Luigi , Alessandri Massimo , Bocchini Salvatore , Verdiani Valerio , Pettinà Giuseppe , Nozzoli Carlo
Published: February 2016

Background. There is uncertainty about the prevalence and clinical characteristics of heart failure (HF) patients with preserved systolic function (PRESYF). Aim. To analyze the prevalence and clinical characteristics of patients with PRESYF in an unselected cohort of subjects consecutively hospitalized for HF. Methods. The study cohort included 338 patients consecutively admitted for HF at 24 Internal Medicine units homogeneously settled in Tuscany area (Italy). We did not have any criteria for exclusion. All patients had an echocardiographic measure of left ventricular ejection fraction (LVEF) within 72 hours from hospital admission. Patients with LVEF > 50% were considered to have PRESYF. Results. The patients with PRESYF were 112 (33,1%), those with depressed systolic function (DESYF) 226 (66,9%). In the group PRESYF were prevalent female sex, hypertensive etiology, and elevated BMI. The distribution for classes of age shows a great frequency of PRESYF in the elderly. Conclusion. About one third of patients admitted for HF have a PRESYF. They are different compared to those with DESYF. A correct identification of this form of HF may be important in clinical practice for more targeted therapeutic options and for prognostic implications.
Psychological impact of carotid endarterectomy: A review of the studies
Authors: Sciarroni Laura , Gremigni Paola , Pedrini Luciano
Published: February 2016

Carotid Endarterectomy (CEA) is a surgical treatment validated to prevent cerebral ischemia, embolism and stroke in patients affected by severe stenosis of the carotid artery. A 1999 systematic review of the literature found controversial results about CEA influence on improvement of post-surgical cognitive performance. Moreover, few studies addressed the issue of the positive effects of CEA on quality of life and depression, reporting also controversial findings. The present review was aimed at considering the last 20 years studies focusing on the effects of CEA on the psychological dimensions. The purpose was to clarify the benefits, in terms of psychological well-being, offered by CEA, besides a reduction of the cardiovascular risk, as well as to have indication to lead further research in this area. Results of the 39 studies considered suggest that, although few studies show cognitive deterioration, most of them show stability with a tendency to improve both in cognitive functions and in other psychological areas. Further research is needed to clarify when it would be appropriate the use of CEA, the characteristics of eligible patients, and psychological as well as physical expected outcomes.
The role of Neopterin in cardiovascular disease
Authors: Pacileo Mario , Cirillo Plinio , De Rosa Salvatore , Ucci Grazia , Petrillo Gianluca , Musto D’Amore Sergio , Sasso Laura , Maietta Paola , Spagnuolo Raffaele , Chiariello Massimo
Published: February 2016

Inflammation plays a key role in the initiation and progression of atherosclerosis but also in the pathophysiology of atheromatous plaque disruption and the development of acute coronary syndromes. Neopterin is a marker of inflammation and of immune system activation, it is synthesized by macrophages, that, once activated, release this substance. Indeed, in clinical evaluation of patients, measurements of plasma levels of neopterin are usually used to evaluate progression of viral infections, renal transplant rejection, severe systemic inflammatory diseases, nephritic syndrome and several autoimmune diseases. This mediator is able to induce a pro-atherothrombotic phenotype in cells of the coronary circulation. Recent data indicate that serum levels of neopterin are elevated in patients with coronary and peripheral artery disease and seem to be a prognostic marker for major adverse cardiovascular events. In particular, neopterin levels predict future major cardiac and vascular adverse events in patients presenting with chronic coronary artery disease, with acute coronary syndromes, and in those with critical limb ischemia. This renders this molecule a useful marker of atherosclerotic plaque activity, permitting the identification of the subjects at highest risk for major adverse cardiovascular events. In line with the above mentioned evidences, patients with high neopterin levels may require aggressive risk factor modification and intensive medical treatment irrespective of the severity of their coronary artery disease. This data suggest a potential clinical use of neopterin as a marker for disease activity in patients with cardiovascular disease.
Secondary Cardiovascular Prevention in the Elderly: beyond clinical aspects
Authors: Calisi Pasqualina , Griffo Raffaele
Published: February 2016

Aging is one of the strongest risk factors for cardiovascular events and even elderly patients with established disease are likely to derive benefits from secondary prevention programs. Unfortunately, few clinical trials have been specificately addressed to older population. However, since this population is rising and presents with intrinsic characteristics, it is worthwhile to consider the problems of the elderly with a sociological and ethical approach too and not only from a medical point of view.
Nutritional care in the cardiac rehabilitation program
Authors: Da Vico Letizia , Biffi Barbara , Masini Maria Luisa , Fattirolli Francesco
Published: February 2016

There is some evidence of the efficacy of nutritional care in modifying eating habits and behavior in patients undergoing cardiac rehabilitation: nutritional care has a relevant role in the secondary prevention of cardiovascular disease. The dietitian is the qualified sanitary professional for nutritional care. The aim of this study was to define the role of dietitians within a health care team in programs of cardiac rehabilitation. In this setting, nutritional care starts with a dietary assessment, which includes a measurement of the anthropometric parameters, and a survey of the patient knowledge and eating habits. If there is no need for change in the patient lifestyle, the patient is addressed to the normal cardiac rehabilitation program with no further nutritional intervention except one session of counseling. When lifestyle changes are needed, the dietitian defines, together with the patient, therapeutic aims and expected results. The following phase is represented by group session with patients and their relatives during which nutritional topics are discussed and nutritional education is provided Afterwards, self-monitoring sheets of eating habits are individually discussed in one visit; a last individual visit is used for a final assessment of nutritional knowledge, dietary habits, and anthropometric parameters. In case of unsatisfactory results, patients are invited to participate to three group session to be held biweekly, during which they interact with the dietitian and take part to exercises and group discussions. When the established targets are reached, the nutritional program includes individual follow up visits at six and twelve months for further assessment of medium term results.
Metabolic frailty in malnourished heart failure patients
Authors: Gualco Alessandra , Opasich Cristina , Brazzo Silvia , Cobelli Franco , Pasini Evasio , Pastoris Ornella , Aquilani Roberto
Published: February 2016

Muscular wasting (MW) and cardiac cachexia (CC) are often present in patients with chronic heart failure (HF). Aim: To identify whether MW and CC are due to malnutrition or impairment of protein metabolism in HF patients. Material and Method: In 78 clinically stable HF patients (NYHA class II-III), aged from 32 to 89 years, we measured anthropometrical parameters and nutritional habits. In the identified 35 malnourished patients, we also measured: insulin resistance, gluconeogenetic amino acids blood concentration and nitrogen balance. Results: Seventy-five patients had eating-related symptoms. However we found significant nutritional impairment in 35 patients only. In addition, these 35 patients had: 1) significant increase of blood Alanine independently from both presence of insulin resistance or food intake reduction and 2) positive nitrogen balance. Conclusion: Food intake is not impaired in CHF patients. In spite of normal food intake, 35 of 78 patients had nutritional impairment with reduced anthropometric parameters and increased blood Alanine. These findings show alteration of proteins metabolism with proteolysis. We believe that specific physical training with nutritional supplement can be an additional therapy able to prevent protein disarrangement in CHF patients.
Phospholipid Scramblases
Authors: Williamson Patrick
Published: February 2016

The distribution of phospholipid types between the two leaflets of a membrane bilayer is a controlled feature of membrane structure. One of the two membrane catalytic activities governing this distribution randomizes the composition of the two leaflets–-the phospholipid scramblases. Two proteins (Xkr8 and TMEM16F) required for the activation of these activities have been identified. One of these proteins (TMEM16F) is quite clearly a scramblase itself and provides insight into the mechanism by which transbilayer phospholipid movement is facilitated.
An Adaptive Finite Element Method with Hybrid Basis for Singularly Perturbed Nonlinear Eigenvalue Problems
Authors: Li Ye
Published: February 2016

In this paper, we propose an uniformly convergent adaptive finite element method with hybrid basis (AFEM-HB) for the discretization of singularly perturbed nonlinear eigenvalue problems under constraints with applications in Bose-Einstein condensation (BEC) and quantum chemistry. We begin with the time-independent Gross-Pitaevskii equation and show how to reformulate it into a singularly perturbed nonlinear eigenvalue problem under a constraint. Matched asymptotic approximations for the problem are reviewed to confirm the asymptotic behaviors of the solutions in the boundary/interior layer regions. By using the normalized gradient flow, we propose an adaptive finite element with hybrid basis to solve the singularly perturbed nonlinear eigenvalue problem. Our basis functions and the mesh are chosen adaptively to the small parameter ε. Extensive numerical results are reported to show the uniform convergence property of our method. We also apply the AFEM-HB to compute the ground and excited states of BEC with box/harmonic/optical lattice potential in the semiclassical regime (0 <ε≪C 1). In addition, we give a detailed error analysis of our AFEM-HB to a simpler singularly perturbed two point boundary value problem, show that our method has a minimum uniform convergence order
The Mass-Preserving S-DDM Scheme for Two-Dimensional Parabolic Equations
Authors: Zhou Zhongguo , Liang Dong
Published: February 2016

In the paper, we develop and analyze a new mass-preserving splitting domain decomposition method over multiple sub-domains for solving parabolic equations. The domain is divided into non-overlapping multi-bock sub-domains. On the interfaces of sub-domains, the interface fluxes are computed by the semi-implicit (explicit) flux scheme. The solutions and fluxes in the interiors of sub-domains are computed by the splitting one-dimensional implicit solution-flux coupled scheme. The important feature is that the proposed scheme is mass conservative over multiple non-overlapping sub-domains. Analyzing the mass-preserving S-DDM scheme is difficult over non-overlapping multi-block sub-domains due to the combination of the splitting technique and the domain decomposition at each time step. We prove theoretically that our scheme satisfies conservation of mass over multi-block non-overlapping sub-domains and it is unconditionally stable. We further prove the convergence and obtain the error estimate in L2-norm. Numerical experiments confirm theoretical results.
Development of a High-Resolution Scheme for Solving the PNP-NS Equations in Curved Channels
Authors: Sheu Tony W. H. , Bhumkar Yogesh G. , Yuan S. T. , Syue S. C.
Published: February 2016

A high-order finite difference scheme has been developed to approximate the spatial derivative terms present in the unsteady Poisson-Nernst-Planck (PNP) equations and incompressible Navier-Stokes (NS) equations. Near the wall the sharp solution profiles are resolved by using the combined compact difference (CCD) scheme developed in five-point stencil. This CCD scheme has a sixth-order accuracy for the second-order derivative terms while a seventh-order accuracy for the first-order derivative terms. PNP-NS equations have been also transformed to the curvilinear coordinate system to study the effects of channel shapes on the development of electroos-motic flow. In this study, the developed scheme has been analyzed rigorously through the modified equation analysis. In addition, the developed method has been computationally verified through four problems which are amenable to their own exact solutions. The electroosmotic flow details in planar and wavy channels have been explored with the emphasis on the formation of Coulomb force. Significance of different forces resulting from the pressure gradient, diffusion and Coulomb origins on the convective electroosmotic flow motion is also investigated in detail.