bluuebunny/crossref_metadata_2025 huggingface dataset:
Security and Connectivity Analysis in Vehicular Communication Networks
Authors: Alshaer Hamada , Muhaidat Sami , Shubair Raed , Shayegannia Moein
Published: September 2013

Reliable Vehicular Ad-Hoc Networks (VANETs) require secured uninterrupted uplink and downlink connectivity to guarantee secure ubiquitous vehicular communications. VANET mobility, multi-fading wireless, and radio channels could result in unsecured and disrupted vehicular communications, isolating some vehicle nodes and making them vulnerable to security attacks. A VANET is considered to be connected and secured if there is a secured path connecting any pair of Communication-Enabled Vehicles (CEVs) in this network. Among many parameters, VANET connectivity depends on two main elements: communication transmission range and statistical distribution characterizing inter-vehicle spacing. To guarantee persistent VANET connectivity, a vehicle transmission radio range must be set properly based on the characteristic of the statistical distribution modeling the inter-vehicle spacing. This chapter analyzes three inter-vehicle spacing models based on exponential, Generalized Extreme Value (GEV), and Exponential with Robustness Factor (EwRF) statistical distributions. Based on vehicle nodes spatial density on a road segment, each vehicle node can adjust its transmission range to increase network connectivity and guarantee ubiquitous vehicular communications. Communications among vehicle nodes are secured through trusted Road-Side Units (RSUs) which distribute efficiently secret keys to vehicle nodes under their coverage to establish secure communication sessions.
Intrusion Detection in Vehicular Ad-Hoc Networks on Lower Layers
Authors: Han Chong , Muhaidat Sami , Abualhaol Ibrahim , Dianati Mehrdad , Tafazolli Rahim
Published: September 2013

Vehicular Ad-Hoc Networks (VANETs) are a critical component of the Intelligent Transportation Systems (ITS), which involve the applications of advanced information processing, communications, sensing, and controlling technologies in an integrated manner to improve the functionality and the safety of transportation systems, providing drivers with timely information on road and traffic conditions, and achieving smooth traffic flow on the roads. Recently, the security of VANETs has attracted major attention for the possible presence of malicious elements, and the presence of altered messages due to channel errors in transmissions. In order to provide reliable and secure communications, Intrusion Detection Systems (IDSs) can serve as a second defense wall after prevention-based approaches, such as encryption. This chapter first presents the state-of-the-art literature on intrusion detection in VANETs. Next, the detection of illicit wireless transmissions from the physical layer perspective is investigated, assuming the presence of regular ongoing legitimate transmissions. Finally, a novel cooperative intrusion detection scheme from the MAC sub-layer perspective is discussed.
Security Issues in Mobile Ad Hoc Networks
Authors: Kumar Sunil , Dutta Kamlesh
Published: September 2013

A Mobile Ad hoc NETwork (MANET) is a self-organizing, infrastructure-less network of mobile nodes connecting by wireless links. In operation, the nodes of MANETs do not have a central control mechanism. It is known for its properties of routable network, where each node acts as a router to forward packets to other specific nodes in the network. The unique properties of MANET have made it useful for large number of applications and led to a number of security challenges. Security in the mobile ad hoc network is a very critical job and requires the consideration of different security issues on all the layers of communication. The countermeasures are the functions that reduce or eliminate security vulnerabilities and attacks. This chapter provides a comprehensive study of all prominent attacks in Mobile Ad Hoc Networks described in the literature. It also provides various proactive and reactive approaches proposed to secure the MANETs. Moreover, it also points to areas of research that need to be investigated in the future.
State of the Art for Near Field Communication
Authors: Moloney Maria
Published: September 2013

This chapter provides an overview of Near Field Communication (NFC) technology. It first introduces the technology and gives a brief history. It examines what the technology is and how it works. It looks at the various operation modes and hardware architectures available for the technology. This is followed by some examples in use of the technology today, in particular NFC in use in mobile payment environment. The chapter then focuses on NFC technology from the perspective of security and privacy of personal information when using the technology. Finally, the chapter looks at the security and privacy challenges that are currently faced by the technology and suggests some possible solutions to these challenges.
Modeling and Verification of Cooperation Incentive Mechanisms in User-Centric Wireless Communications
Authors: Aldini Alessandro , Bogliolo Alessandro
Published: September 2013

User-centric wireless networks are characterized by a community-scale objective aiming at the shared provision of user-generated services and contents. This may be contrasted by the reticence of individuals to share the limited resources of mobile devices. Hence, cooperation incentives play a key role to promote prosocial decisions and to isolate selfish nodes and cheating behaviors. In particular, trust-based incentives and remuneration are used to induce collaborative behaviors in Wi-Fi communities. Typically, these mechanisms are based on reputation infrastructures and virtual currency systems, the application of which should not hinder the normal operation of the network. In this chapter, the authors present an approach to the combined use of indirect rewards deriving from trust-based incentives and direct rewards deriving from remuneration. The effectiveness and efficiency of such an approach in the setting of user-centric wireless networks is verified by conducting a formal study of the benefits of the joint application of these rewards and of the related impact upon performance.
Statistical Analysis of Spectral Entropy Features for the Detection of Alcoholics Based on Elecroencephalogram (EEG) Signals
Authors: Shri T.K. Padma , Sriraam N.
Published: September 2013

EEG happens to be an important tool for brain study providing a non- invasive and cost effective method to detect the effects of alcohol on the human brain. This paper highlights the importance of statistical analysis to determine the usefulness of spectral entropy features for discriminating alcoholics from healthy subjects. The open source EEG database consisting of 10 alcoholic and 10 control subjects recordings under visual stimulus is considered for the study. The EEG signal is preprocessed to remove eye blink artefact using independent component analysis (ICA) and the gamma sub band is extracted by using an elliptic band pass filter to obtain the visually evoked pattern (VEP) signal. The spectral entropy (SEN) coefficients are computed on all the 61 VEP signals of each subject. To obtain a statistical measure of SEN coefficients suitability for classifying the alcoholic EEG, ANOVA tests are performed. Results show that the test exhibits interesting observations in the form of p-value <0.05 (accepted significance level) for most of the channels and p-value >0.05 for the remaining channels. This study may help in identifying those significant channels (p<0.05) which contribute to the classification of both the groups.
Web 2.0 for Language Learning
Authors: Luo Tian
Published: September 2013

This literature review study explores 43 empirical research studies that report on the integration of Web 2.0 tools into language learning and evaluate the actual impact of their use. In particular, this review aims to identify the specific Web 2.0 tools integrated in the educational settings, theoretical underpinnings that are commonly used to frame the research, methodologies and data analysis techniques that scholars employ to analyze their research data, the benefits and challenges scholars spotted in their research findings, the pedagogical implications in using Web 2.0 for language learning and future research directions that scholars offer from their research.
Right to Health Information and an Example of Its Implementation
Authors: Sarbadhikari Suptendra Nath
Published: September 2013

Mousavi et al. (2013) have correctly noted the importance of information and knowledge, as mentioned in most Charters, for attaining the right to health. The practical administration also needs scientific standards, administrative instructions, and clinical guidelines designed to implement the right to health. The author, in this paper, provides an example of implementation.
Investigating Goal-Oriented Requirements Engineering for Business Processes
Authors: Poels Geert , Decreus Ken , Roelens Ben , Snoeck Monique
Published: September 2013

Business processes are designed to execute strategies that aim at achieving organisational goals. During the last decade, several methods have been proposed that prescribe the use of goal-oriented requirements engineering techniques for supporting different business process management activities, in particular business process modelling. The integration of goal modelling and business process modelling aims at increasing the alignment between business strategies and the processes with their supporting IT systems. This new research area, which the authors call Goal-Oriented Requirements Engineering for Business Processes (GORE-for-BP), is developing rapidly, but without a clear conceptualization of the focus and scope of the proposed GORE-for-BP methods. Furthermore, an overview is lacking of which methods exist and what their level of maturity is. This paper therefore presents a research review of the GORE-for-BP area, with the aim of identifying relevant methods and assessing their focus, scope, and maturity. This study used Systematic Literature Review and Method Meta-Modelling as research methods to identify and evaluate the state of the GORE-for-BP research area and to propose a research agenda for directing future research in the area. Nineteen methods were identified, which is an indication of an active research area. Although some similarities were found with respect to how goal models are transformed into business process models (or vice-versa), there is also considerable divergence in modelling languages used and the extent of coverage of typical requirements engineering and business process management lifecycle phases. Furthermore, the exploitation of requirements engineering techniques in the full business process management lifecycle is currently under researched. Also, the maturity of the methods found in terms of the formalisation of the transformation activity, the elaboration of method guidelines, and the extent to which methods are validated, can be further improved.
Learner Self-Regulation and Web 2.0 Tools Management in Personal Learning Environment
Authors: Yen Cherng-Jyh , Tu Chih-Hsiung , Sujo-Montes Laura E. , Armfield Shadow W. J. , Chan Junn-Yih
Published: September 2013

Web 2.0 technology integration requires a higher level of self-regulated learning skills to create a Personal Learning Environment (PLE). This study examined each of the four aspects of learner self-regulation in online learning (i.e., environment structuring, goal setting, time management, & task strategies) as the predictor for level of initiative and sense of control with regard to iGoogle gadgets management in PLE. This study has concluded that goal setting, time management, and task strategies in self-regulated learning can predict level of initiative in organizing PLE. Furthermore, goal setting and task strategies can predict sense of control in PLE management.
Usage Profiles
Authors: Vollino Bruno , Becker Karin
Published: September 2013

As part of web services life-cycle, providers frequently face decision about changes without a clear understanding of the impact on their clients. The identification of clients’ consumption patterns constitutes invaluable information to support more effective decisions. In this paper, the authors present a framework that supports the discovery of service usage profiles, to bring awareness on the distinct groups of consumers, and their usage characterization in terms of detailed service functionality. The framework encompasses a process to cluster client applications and derive usage profiles. The paper also discusses how usage profiles can help to access the real impact on clients of incompatible changes performed over service descriptions, and presents a usage-oriented compatibility assessment algorithm. Experimental results are presented for both the profile discovery process and profile-based compatibility analysis.
The Association between Body-size and Habitat-type in Tiger Beetles (Coleoptera, Cicindelidae) of Sri Lanka
Authors: Dangalle Chandima D , Pallewatta Nirmalie , Vogler Alfried P
Published: September 2013

Body size is an important feature of an animal that is linked with its life history, morphology, physiology and ecology. Understanding the association between body size and habitat type of an animal and the underlying causes for this are important for determining their distribution. The present study examines the association between body size and habitat types of tiger beetles in Sri Lanka and the environmental correlations for these associations. Morphometric parameters of tiger beetles and environmental parameters (air temperature, solar radiation, relative humidity, wind speed and, the colour, temperature, moisture content, pH and salinity of soil) in each habitat were recorded. Ten tiger beetle species were found from 37 locations which included coastal, riverine, urban and reservoir habitats. Species with larger body and mandible sizes prefer coastal and reservoir habitats with high wind speed, low soil moisture and high soil pH, whereas species with smaller body and mandible sizes prefer riverine habitats with low wind speed, high soil moisture and low soil pH. Species with smaller body size may also prefer urban habitats which may be due to similarity of environmental conditions that prevails in these two sites. These findings will assist in predicting the distribution of tiger beetles within various habitat types of Sri Lanka.DOI: http://dx.doi.org/10.4038/cjsbs.v42i1.5898 Ceylon Journal of Science (Bio. Sci.) 42 (1): 41-53, 2013
Metaphase Displacement and Anaphase Lagging during Induced Lymphocyte Culture in Cattle and Buffalo
Authors: Katragadda Sanghamitra , Patel Rajesh K , Kotikalapudi Rosaiah
Published: September 2013

Chromosomal aberrations are of great concern in dairy animals worldwide as they are usually associated with reduced fertility or infertility. There are multiple reasons which may cause chromosomal aberrations during mitosis and meiosis. To understand the probable cause of aberrations, a simple study was performed during induced lymphocyte culture. The lymphocyte cultures were setup using the blood samples of cattle and buffaloes. Samples were harvested without adding ethedium bromide and colchicine. The Giemsa stained chromosome slides were screened under the microscope (100X) and photographed with attached system.DOI: http://dx.doi.org/10.4038/cjsbs.v42i1.5900 Ceylon Journal of Science (Bio. Sci.) 42 (1): 63-66, 2013
Open questions on bioequivalence: the case of cholecalciferol
Authors: Marzo Antonio , Barassi Anna , Porro Elisabetta
Published: September 2013

Cholecalciferol or vitamin D3 is an endogenous substance with the typical problems of bioavailability/bioequivalence of this class of substances. A previous trial has shown that, if administered orally at a dose of 800-10,000 IU and bioassayed as its 25-hydroxy metabolite, a slow absorption without an evident peak shape can be expected. However, if administered orally at a dose of 100,000-300,000 IU, this drug shows a well-defined peak shape of its metabolite 25-hydroxyvitamin D3 (which is exceptionally long-lasting) with time to peak (tmax) at seven days and a kinetic profile requiring 84 days or more to restore predose base-line levels. A recent paper has described a new bioassay of cholecalciferol in serum with a serum concentration-time curve after oral administration of 70 μg (2800 IU). An evident peak shape with Cmax of approximately 4 ng/mL was achieved at 12-24 h after administration. Baseline was restored after 96 h. However, these pharmacokinetic data were obtained in only one subject. This approach for bioassay of the parent drug seems to be more suitable for bioequivalence trials of cholecalciferol, even if more data concerning application are needed to adequately prepare a bioequivalence protocol. Therefore, the case of cholecalciferol appears to be extremely complex and remains one of the unanswered questions concerning bioequivalence that has not been taken into consideration in operating guidelines.
Thrombolytic treatment in the oldest-old patient with acute ischemic stroke: an update on current evidence
Authors: Maioli Fabiola , Procaccianti Gaetano , Nativio Valeria , Arnone Giorgia , Nardi Roberto , Sacquegna Tommaso , Coveri Maura
Published: September 2013

The incidence of ischemic stroke rises exponentially with age, with a steep increase in the age interval between 75 and 85 years. Thrombolytic therapy restores cerebral blood flow in patients with acute ischemic stroke of any etiology by using drugs that dissolve blood clots. Infusion for 1 h of alteplase at the dose of 0.9 mg/kg within 3 h of the start of the symptoms is associated to a 30% increase in the likelihood of gaining a favorable outcome with respect to placebo. There is strong evidence that selected patients with ischemic stroke may benefit from intravenous thrombolysis when treated within 3 h. The aim of the study was to evaluate available evidence for the efficacy and safety of thrombolytic therapy in patients with ischemic stroke aged 80 years and over. Compared to younger stroke patients treated with thrombolytic therapy, those aged 80 years and over have higher acute mortality due to symptomatic intracranial hemorrhage. However, functional outcome at six months is significantly better for over-80-year-olds than younger patients. There is a need for screening tools that take into account pre-stroke functional and cognitive status that are able to identify those over-80-year-old patients with ischemic stroke who can most benefit from thrombolytic treatment. Available evidence supports further recruitment of oldest-old patients into ongoing trials of thrombolysis.
Clinical experience with fondaparinux in antiaggregate patients undergoing total hip and knee arthroplasty
Authors: Grappiolo Guido , Scardino Marco , Mazziotta Giuseppe , Quaini Stefano , Lodigiani Corrado , Ferrari Matteo Carlo
Published: September 2013

Patients undergoing total hip arthroplasty or total knee arthroplasty have a high risk for post-operative venous thromboembolism. The current study addressed the use of fondaparinux post-operatively in 556 patients with antiplatelet therapy in order to prevent deep vein thrombosis as well as demonstrate efficacy in preventing arterial thrombotic events. Results provided evidence for a safe and effective prophylaxis strategy, involving the change from low molecular weight heparin pre-operatively to fondaparinux postoperatively. Also, fondaparinux proved effective as a unique post-operative therapy in the prevention of venous thromboembolism with no adverse effects, such as major bleeding or arterial thrombosis in patients with pre-operative antiplatelet therapy.
Beyond monotheism? Some remarks and questions on conceptualising �monotheism� in Biblical Studies
Authors: Frevel Christian
Published: September 2013

In the first part of this article I outline serious objections against the concept of monotheism. I will ask whether the ambiguity and the problem discredit the concept of monotheism as inappropriate for Biblical Studies, or whether it calls for differentiation. In the argument following thereupon, the concept is found to be more useful to describe certain stages of the conceptual and linguistic development of Israelite religion. The term and concept of monotheism in Biblical Studies is necessary, but not sufficient, if we want to reconstruct the religious history of Israel, Judah, Yeh�d and Early Judaism or Judaisms. In this article I propose categories such as implicit monotheism, intolerant monolatry, implicit exclusion, explicit uniqueness, monotheism as implication et cetera, which are especially useful if we want an accurate description of the statements. This makes the category of monotheism useful as heuristic and relational category.
A Sharp Error Estimate for Numerical Fourier Fransform of Band-Limited Functions Based on Windowed Samples
Authors: Goebbels Steffen J.
Published: September 2013

W. Dickmeis and R. J. Nessel published their first version of a quantitative extension of the classical uniform boundedness principle in [J. Approx. Theory 31 (1981), 161–174]. It is a general approach to finding counterexamples that prove sharpness of error estimates. So far applications of this principle include error bounds for approximation processes, cubature rules, ordinary and partial differential equations, and reconstruction from samples. Here we discuss the error of discrete approximations of the Fourier transform based on windowed samples for band-limited functions. The results can be applied to the Hann- and Blackmann–Harris-window but also to window-functions that enable higher orders of convergence. We describe a class of such windows.
Corrosion at a Holiday in an Organic Coated-Metal Substrate System
Authors: CRAIG B. D. , OLSON D. L.
Published: September 2013

The galvanic corrosion at a holiday in an organic coating was investigated by measuring the galvanic current as a function of time. It was found that an area of exposed metal (holiday) in the coating will be anodic to the coated areas. Water uptake and ion transport of the coating are significant factors affecting the corrosion taking place at a holiday. Thickness of the coating was also found to be an important influence on the corrosion rate at a holiday.
Endurance Limit Enhancement of Notched, 1018 Steel in Sea Water—Specimen Size and Frequency Effects
Authors: HARTT W. H. , HOOPER W. C.
Published: September 2013

Notched 1018 steel specimens of three different thicknesses have been fatigued at 31 Hz in sea water as a function of both stress and electrochemical potential. Additionally, specimens of one thickness were fatigued at 3.3 Hz. The phenomenon of endurance limit enhancement, whereby cathodic polarization renders notched steel more resistant to fatigue in sea water than in air, was found to be more pronounced for the lower frequency and for the thinnest specimen. It is projected that endurance limit enhancement is a consequence of calcareous deposits which accumulate within the fatigue crack. The extent to which such deposits occur is thought to depend upon the cathodic current density within the crack and the extent of mixing between the bulk and crack electrolytes, as the latter is ejected and ingested on each cycle. A possible influence from hydrogen is also discussed.
Surface Composition of a Type 316 Stainless Steel Related to Initiation of Crevice Corrosion
Authors: HULTQUIST G. , LEYGRAF C.
Published: September 2013

On the basis of different surface treatments of a Type 316 stainless steel, results of protective film composition as obtained by Auger electron spectroscopy (AES) are related to resistance to initiation of crevice corrosion. The nickel content of the protective film was similar after all treatments, whereas the chromium surface content was found to differ between different surface treatments. A direct relationship between chromium surface enrichment and the resistance against crevice corrosion initiation was found which was independent of the presence of nonmetallic inclusions. The results suggest that initiation of crevice corrosion and initiation of pitting corrosion are different in nature.
The Effect of Scan Rate on Pitting Potentials of High Performance Alloys in Acidic Chloride Solution
Authors: MANNING P. E.
Published: September 2013

The effect of potential scan rate on the pitting potential determination of several high performance alloys in acidic chloride solution at 70 C was documented. Materials from several alloy classifications were examined including austenitic stainless steel, duplex stainless steel, 20-type stainless steel, and nickel base alloys. The functional relationship of pitting potential versus scan rate was dependent on the material studied. Results at intermediate and rapid scan rates were dependent on the material studied and on the experimental procedure. The response of the pitting potential of a given alloy to intermediate and rapid scan rates appears to be a function of the kinetics of passive film formation at the corrosion potential and at applied potentials. Therefore, the most promising accelerated electrochemical tests for localized corrosion resistance are the slow scan rate and constant potential pitting tests. Hastelloy alloy G was found to be resistant to pitting corrosion at all applied potentials in this environment. Additionally, the microstructural sites most susceptible to stable pit initiation were determined for the alloys investigated.
The Effects of Sulfur and Phosphorus on the Intergranular Corrosion of 304 Stainless Steel
Authors: BRIANT C. L.
Published: September 2013

This paper reports a study of the effects of sulfur and phosphorus on the sensitization and intergranular corrosion of 304 stainless steel. It is shown that sulfur has little effect on the intergranular corrosion of the material, except at the high electrochemical potentials of the Huey test and oxalic acid test. At these potentials chromium sulfides precipitated at the grain boundaries and in the matrix are preferentially attacked. Phosphorus has little effect on intergranular corrosion as measured by the modified Strauss test, but it greatly accelerates intergranular corrosion in the Huey test. The magnitude of this effect depends on the extent of chromium depletion. It is also shown that in all of the alloys studied grain boundaries in a given sample corrode at varying rates. This variation appears to be a result of variation in grain boundary structure and hence in precipitation and segregation.
UTILIZAÇÃO DE PROBIÓTICOS SOBRE O GANHO DE PESO EM BOVINOS DA RAÇA NELORE
Authors: Almeida Luis Eduardo Stevanato de , Genaro Sandra Cristina , Geroti Thais Cristina de Souza , Galina Neuza Maria Frazatti , Giuffrida Rogerio , Pardo Paulo Eduardo , Penha Luciana , Camacho Reinaldo , Santos Marcos Oliveira
Published: September 2013

This study evaluated the effect of probiotic proenzyme ®, added to the mineral mixture in a weight gain of cattle in extensive grazing system. We used 40 animals, Nelore bulls (Bos indicus) aged approximately 12 months, randomly divided into 2 groups (20 animals / group): control group (CG) received only mineral mixture and probiotic group (GP) with added probiotic. Calves were weighed on days 0 and 30 from 30 to 90 days and 00 to 90 days. The results showed a significant increase in weight gain in animals only GP in the first 30 days
Numerical Simulations for Average Temperature Differential Stirling Engine
Authors: Bataineh Khaled M.
Published: September 2013

A second order mathematical model taken into account thermal losses for average temperature differential Stirling engine is developed. Dynamic simulation of the engine based on mathematical formulation is carried out under different operating and geometrical conditions to investigate the engine performance. The developed model is used to investigate the influence of geometrical and physical parameters on the performance of Stirling engine. Design optimization of a mean temperature differential Stirling engine is carried out. Finally optimal parameters have been determined.
Development and investigation of skin melanoma phantoms for ultrasonic examination
Authors: Andrėkutė Kristina , Subotinaitė Ilona , Valiukevičienė Skaidra , Raišutis Renaldas
Published: September 2013

Background. The purpose of this study was to develop skin mimicking phantoms with melanoma-like insertion with acoustic properties similar to the human skin. In order to guarantee that these phantoms are suitable for mimicking of the skin, we measured their parameters with an ultrasonography tool and compared with the human skin properties measured by other authors.
Materials and methods. Distilled water, gelatin and Intralipid® 20% IV fat emulsion were mixed in different proportions thus manufacturing four models of the skin tissue. For melanoma-mimicking insertion only gelatin and distilled water were used. Ultrasonic examinations of manufactured phantoms were performed with the ultrasound system DUB-USB equipped with a mechanically scanned single-element focused transducer.
Results. The speed of sound and the attenuation coefficient of all the manufactured phantoms were evaluated. This study demonstrates that the speed of sound decreases increasing concentration of Intralipid and it is close to the human skin tissue. The ultrasound velocity in the phantom material varied from 1 533.9 m/s up to 1 565.8 m/s depending on Intralipid fat emulsion concentration. The ultrasound velocity in the melanomalike insertion was 1  602.4  ±  23.5  m/s (mean  ±  SD). It was also found that the concentration dependent magnitude of attenuation increment matched the theoretically defined tendency. The attenuation in the range of 0.15–0.4  dB/mm/MHz was estimated in the phantoms possessing different concentrations of Intralipid. The attenuation in the melanomalike insertion region was 0.16  ±  0.02  dB/mm/MHz (mean  ±  SD). The magnitude of the attenuation coefficient is close to the attenuation in the human tissue.
Conclusions. The four skin tissue mimicking phantoms were developed and their acoustic properties were estimated during this study. The investigation showed that the estimated speed of sound and the attenuation coefficient were close to the values being estimated in the human skin tissue. Furthermore, it was noted that the acoustic proper­ties could be controlled by changing the concentration of Intralipid and such a flexible phantom could be used for mimicking of the external tissue of the human body.
Gender, Geographic Locations, Achievement Goals and Academic Performance of Secondary School Students from Borno State, Nigeria
Authors: Musa Alice K. J.
Published: September 2013

The paper examined gender, geography location, achievement goals and academic performance of senior secondary school students in Borno State, Nigeria. The sample consists of 827 students from 18 public boarding secondary schools across South and North of Borno State: 414 (50.1 per cent) males and 413 (49.9 per cent) are females; 414 (50.1 per cent) are from South of Borno State, 413 (49.9 per cent) from North of Borno State, respectively. An Achievement Goals Scale with a Cronbach alpha of 0.64 was used to measure achievement goals. Tests in English and Mathematics were used to measure academic performance in English and Mathematics and overall academic performance. The data was analysed using MANAVA statistics. The results reveal that male students are more learning goal oriented and also performed significantly better than females in English and overall academic performance but not in Mathematics. Students from Southern Borno State are more learning goal oriented and performed significantly better than those from Northern Borno State in English, Mathematics and overall academic performance. Geographic locations moderate the effects of gender on students' learning goal, Mathematics and overall academic performance.
Clinical Analysis, Management and Outcome of Duane's Retraction Syndrome at a Tertiary Eye Care Centre in South India
Authors: Ravindran Meenakshi , Pawar Neelam , Karkera Radhika P , Kunnatur Rajagopal
Published: September 2013

Aim:

To study clinical features, management & outcome of Duane's retraction syndrome (DRS).

Materials & Methods:

This prospective, interventional, non randomised study of 102 patients diagnosed with DRS was done from September 2009 to August 2011. Various characteristics studied included sex, age at presentation, laterality, manifest primary position horizontal deviation, upshoot and downshoot, amblyopia, and associated ocular and systemic abnormalities. Follow up for non surgical patients was for minimum period of 6 months. Surgery was advised in patients with anomalous head posture of more than 15 degrees, cosmetically unacceptable upshoot or downshoot, significant deviation in primary position and globe retraction. Post operative follow up of surgical cases was done at 1 month and were followed up for a minimum period of 6 months.

Results:

Of the total 102 patients, 92 (90.2%) had unilateral and 10 (9.8%) had bilateral DRS. Type I (78.57 %) was the most common while Type II (2.68%) was the least common among unilateral as well as bilateral cases. Preponderance for the female gender was seen in unilateral and bilateral cases. Left eye preponderance was seen in unilateral cases. A significant association was found between type of unilateral DRS and type of ocular deviation in primary gaze, direction of face turn, presence of upshoot/downshoot. Exotropia (41.2%) was the most common ocular deviation in primary position in our study. Exotropia was more common in unilateral cases and esotropia more in bilateral cases. Surgical correction was done in 20 patients (22 eyes). Patients with both esotropia and exotropia who underwent surgical correction showed a significant improvement after surgery (p=0.0368 and 0.0011 respectively). There was a significant improvement of abnormal head posture (AHP) and globe retraction post operatively (p =0.014 and p =0.005 respectively).

Conclusion:

Unilateral types I, II, and III Duane syndrome and bilateral cases differs in the primary position horizontal deviation, upshoot and downshoot, and associated ocular abnormalities. Surgical intervention is recommended in patients with abnormal head posture (AHP), overshoot, globe retraction and significant deviation in primary position.
Pulse Radiolytic Polarography: The Reduction of the Ascorbic Acid Radical and of the Ferrihexacyanide Anion at the Mercury Electrode
Authors: Grätzel M. , Henglein A.
Published: September 2013

The relatively long lived ascorbic acid radical or the ferrihexacyanide anion were produced by a 20 ns pulse of high energy electrons in N2O saturated, 10−3 molar solutions of ascorbic acid or ferrohexacyanide anion, respectively. Their cathodic currents at a hanging mercury drop electrode were recorded as function of time in the micro to millisecond range. The analysis of current‐time curves at constant potential was carried out in the same way as in the single potential jump experiments of conventional electrochemistry. Absolute values of the rate constant of the transfer processes could be obtained for various potentials. The transfer coefficient was found to be 0.23 for the ascorbic acid radical and 0.15 for the ferrihexacyanide anion. The exchange current density at the standard potential of the system [Fe(CN)6]3‐ [Fe(CN)6]4‐ was calculated as 3.5 mA · cm−2 at a concentration of 10−3 M.
Kinetics of Electrode Processes in Pulse Radiolytic Polarography of Short‐Lived Free Radicals
Authors: Grätzel M. , Henglein A. , Bansal K. M.
Published: September 2013

Electrode processes of free radicals formed by a short pulse of high energy electrons are influenced by

a) diffusion of the radicals,

b) second order disappearance of the radicals,

c) hindrance of the transfer reaction.

Approximations for the evaluation of polarographic current‐time curves are discussed. The Birk‐Perone approximation developed for flash photo‐polarography is applied to describe the kinetics of electrode processes which have a large transfer rate constant. Experiments are carried out on the oxidation of the radical anions C6H5COCH3 and CH3COCH3 and on the reduction of CH3COCOCH3 (at potentials where the transfer reaction is fast). The second order rate constants for radical‐radical reactions derived from the polarographic current‐time curves agree to within 20% with the optically determined rate constants. The reduction of CH3COCOCH3 (at potentials where the rate of the transfer reaction is slow) is investigated as an example for electrode processes which depend on all three effects a), b), and c) mentioned above. The absolute rate constant of the transfer reaction was obtained for various potentials. The transfer coefficient amounts to 0.21 at pH = 6 for the reduction of CH3COCOCH3.
Pulse Radiolytic Polarography: The Kinetics of the Oxidation of the Ethanol Radical at the Mercury Electrode
Authors: Grätzel M. , Bansal K. M. , Henglein A.
Published: September 2013

The ethanol radical was produced in N2O saturated, 2 · 10−3 molar aqueous ethanol solutions by a 20 ns pulse of high energy electrons. The anodic current of the radical was recorded as a function of time at various potentials of the mercury electrode and at various pH‐values of the solution. The concentration of the radical in the bulk of solution as a function of time was simultaneously recorded by optical measurements. Analysis of the data shows that the electrode process is reversible in the 10−5 s range at pH > 12, i.e. when the base form of the radical is mainly present. Transfer rate constants of more than 1.0 cm s−1 are calculated. Below pH = 12, the electrode process becomes more irreversible with decreasing pH. The kinetics of the oxidation of the acid form of the radical is strongly influenced by its adsorption at the mercury electrode. The influence of electrochemically inactive adsorbed solutes is also investigated: Adsorbed sulfate ions strongly decrease the anodic current at potentials more positive than ‐ 0.5 V. Fluorid ions exert a less pronounced effect. Adsorbed alcohol molecules have a promoting effect on the oxidation of the ethanol radical.
Pulse Radiolytic Polarography: Adsorption Effects in the Electrode Kinetics of Short‐Lived Free Radicals
Authors: Henglein A. , Gratzel M.
Published: September 2013

Mathematical solutions for the polarographic current as a function of time are given for the case of two‐step electrode reactions: R → Ra → P (R: radicals produced homogeneously in solution by a short pulse of high energy electrons; Ra: radical adsorbed at the electrode; P: product of oxidation or reduction). If R is long‐lived or disappears according to first order kinetics, the differential equations involved are amenable to solution. If R disappears by second order kinetics, an explicit solution cannot be given; the solution for first order disappearance, however, may well be applied to such cases at times shorter than the first half‐life time of the radical. The current‐time curves exhibit a maximum whose magnitude and position with respect to time can be expressed in terms of the ratio V = k/k1 where k is the transfer rate constant in s−1 and k1 the time constant of the disappearance of the radicals in the solution, k1 is measured by recording the optical absorption of the radicals as a function of time.

The current‐time curves obtained for the oxidation of the ethanol radical at a mercury electrode are described by the above two‐step electrode reaction, k is obtained at different electrode potentials. The transfer coefficient for the oxidation of the ethanol radical at pH = 6 is 0.37.
Statistical Mechanics of a Three‐Component System: PdBH
Authors: Mehlmann R. , Husemann H. , Brodowsky H.
Published: September 2013

The mixing behavior of the binary systems Pd ‐ H and Pd ‐ B was previously interpreted in terms of three effects:

The solute atoms H and B, respectively, occupy octahedral sites.

They donate their valence electrons to the 4d and 5s bands of the palladium, raising its Fermi energy.

There exists an energy of attraction between the interstitial particles.

This model is now applied to the ternary system Pd ‐ B ‐ H. The Fermi energy contribution to the thermodynamic properties is treated strictly as a known function of the total valence electron concentration, which is in agreement with magnetic susceptibility measurements on these systems.

The quasichemical approach, which was used to calculate the thermodynamic properties connected with the energy of attraction in the binary systems, is extended to the three‐component system Pd ‐ B ‐ H. In addition to the known energies of attraction between two like particles there appears a third parameter, the energy of attraction between unlike particles.

The method is applied to hydrogen absorption measurements on Pd ‐ B alloys. Good fit is obtained with one adjustable parameter, the interaction energy between unlike particles. An interpretation is given for the three energies of attraction in terms of a lowering of the lattice strain energy for nearest neighbor interstitial atoms.
Developments in Quantitative Data Display and Their Implications for Evaluation
Authors: Lysy Christopher
Published: September 2013

Quantitative displays discussed in this chapter can be used across multiple evaluation stages, although this chapter pays significant attention to visualization as a mechanism for communicating data and results. The chapter is split into two parts. The first part illustrates some newer chart types that have gained popularity over the last decade, and identifies evaluation situations where these new visualizations could be useful. The second part examines new display functionality made possible by the Web and discusses how these features can be used to increase the amount of data presented while maintaining visual simplicity. © Wiley Periodicals, Inc., and the American Evaluation Association.
Brain Volume and Fatigue in Patients With Postpoliomyelitis Syndrome
Authors: Trojan Daria A. , Narayanan Sridar , Francis Simon J. , Caramanos Zografos , Robinson Ann , Cardoso Mauro , Arnold Douglas L.
Published: September 2013

Background

Acute paralytic poliomyelitis is associated with encephalitis. Early brain inflammation may produce permanent neuronal injury with brain atrophy, which may result in symptoms such as fatigue. Brain volume has not been assessed in postpoliomyelitis syndrome (PPS).

Objective

To determine whether brain volume is decreased compared with that in normal controls, and whether brain volume is associated with fatigue in patients with PPS.

Design

A cross‐sectional study.

Setting

Tertiary university‐affiliated hospital postpolio and multiple sclerosis (MS) clinics.

Participants

Forty‐nine ambulatory patients with PPS, 28 normal controls, and 53 ambulatory patients with MS.

Methods

We studied the brains of all study subjects with magnetic resonance imaging by using a 1.5 T Siemens Sonata machine. The subjects completed the Fatigue Severity Scale. Multivariable linear regression models were computed to evaluate the contribution of PPS and MS compared with controls to explain brain volume.

Main Outcome Measurements

Normalized brain volume (NBV) was assessed with the automated program Structured Image Evaluation, using Normalization, of Atrophy method from the acquired magnetic resonance images. This method may miss brainstem atrophy.

Results

Technically adequate NBV measurements were available for 42 patients with PPS, 27 controls, and 49 patients with MS. The mean (standard deviation) age was 60.9 ± 7.6 years for patients with PPS, 47.0 ± 14.6 years for controls, and 46.2 ± 9.4 years for patients with MS. In a multivariable model adjusted for age and gender, NBV was not significantly different in patients with PPS compared with that in controls (P = .28). As expected, when using a similar model for patients with MS, NBV was significantly decreased compared with that in controls (P = .006). There was no significant association between NBV and fatigue in subjects with PPS (Spearman ρ = 0.23; P = .19).

Conclusions

No significant whole‐brain atrophy was found, and no association of brain volume with fatigue in PPS. Brain atrophy was confirmed in MS. It is possible that brainstem atrophy was not recognized by this study.
General practitioners’ assessment of, and treatment decisions regarding, common mental disorder in older adults: thematic analysis of interview data
Authors: STRACHAN JENNIFER , YELLOWLEES GILL , QUIGLEY APRIL
Published: September 2013

Primary and secondary care services are charged with failing to adequately detect and treat mental disorder in older adults due to the ‘understandability phenomenon’; the belief that mental disorder in old age is inevitable and therefore not worthy of intervention. Quantitative data appear to support this hypothesis but lack the explanatory power of detailed accounts. Nine general practitioners (GPs) participated in group interviews about their assessment and treatment of older patients, and their expectations and experience of referral to secondary care. Resulting transcripts were subject to Thematic Analysis. Respondents recognised the unique features of these clients, and their impact on the detailed, recursive processes of assessment, clinical decision-making and intervention. GPs described confidence in managing most cases of mental disorder, describing the role of secondary care as one of consultancy in extreme or unusual cases. GPs did view mental disorder as commonly originating in adverse circumstances, and queried the validity of pharmacological or psychological interventions in these cases. They did not, however, equate understandability with acceptability, and called for social interventions to be integrated with health-care interventions to tackle the cause of mental disorder in older adults. At a wider level, findings highlight the discrepancy between assumptions about GP attitudes and actions, and their own accounts. At a local level, findings will assist in focusing secondary care service development where need is perceived, into consultancy and training.
Response to Tatiana Kostadinova's review of Spoils of Truce: Corruption and State-Building in Postwar Lebanon
Authors: Leenders Reinoud
Published: September 2013

Tatiana Kostadinova's critical remarks and questions are spot on. Some of them had been on my mind while researching the book, and they all deserve to be raised. I would argue that the possible ways by which my case study could be viewed as relevant to more generalizing approaches to corruption are twofold.
Dictators and Rebellious Civilians
Authors: Bozóki András
Published: September 2013

Thanks to research conducted in the past few years, our understanding has been significantly expanded concerning democracy and authoritarian regimes, as well as the means of both destroying and rebuilding democratic institutions. While there is a clear link between a developed economy and democracy, the relationship is not self-evident in all cases. Also, economic growth is not conducive to the development of democracy under all circumstances, especially when the distribution of wealth is not considered fair by all citizens. In and of itself an election, even a competitive one—long considered a democratic minimum—does not guarantee the survival of a democracy, as strongmen have learned how to run an authoritarian system behind an electoral veil. The majority of autocratic leaders use the concept of democracy as a screen for building a political regime antithetical to the spirit and practice of a real democracy. Autocrats adopt a number of democratic institutions only to subvert their original purposes. While they pose as democrats, instead of a liberal democracy they initially organize amajoritariandemocracy, followed by anilliberaldemocracy that ignores human rights. This is but one step away from an autocratic turning point, the rejection of all democratic principles. “Potemkin democracies” may even hold (limited) open elections organized so that the outcome will not threaten the foundations of the existing regime.