bluuebunny/crossref_metadata_2025 huggingface dataset:
Driver Preference for Crosswalk Marking Patterns
Authors: Iragavarapu Vichika , Fitzpatrick Kay , Chrysler Susan T.
Published: December 2011

The objective of this study was to investigate driver preference for three crosswalk marking patterns (transverse lines, continental markings, and bar pairs). Ratings were collected from participants driving an open-road course that included existing markings and markings specifically installed for the study. The participants gave a subjective rating of appearance based on how easy it was to see each crosswalk. These ratings were recorded on a scale of A through F (with no E), with A being excellent or very easy to see and F being completely unacceptable or very hard to see. The 78 participants were about evenly divided between male and female groups and between younger (age < 55 years) and older (age ≥ 55 years) groups. Data were collected during two periods: daytime (sunny and clear or partly cloudy) and nighttime (street lighting on). Overall, bar pairs and continental markings were preferred over transverse markings. The subjective rating findings discussed in this paper mirror detection distance results obtained from a recent FHWA field visibility study of the three crosswalk marking patterns.
Vertebral body split fracture after a single-level cervical total disc replacement
Authors: Tu Tsung-Hsi , Wu Jau-Ching , Fay Li-Yu , Ko Chin-Chu , Huang Wen-Cheng , Cheng Henrich
Published: December 2011

Cervical total disc replacement (TDR) is a viable option for the surgical treatment of degenerative disc disease. This 67-year-old nonsmoking male patient underwent single-level ProDisc-C cervical TDR at C5–6 without any intraoperative problem. His radicular pain improved and he had no neck pain immediately after the operation. However, on postoperative Day 3, a radiograph demonstrated a vertical split fracture of the C-5 vertebra. This fracture was managed conservatively, and 2 years postoperatively a follow-up CT scan demonstrated stable device position and fusion of the fracture. Although the linear fracture caused no neurological symptoms or device migration, the authors advocate prudence in selection and installation of keel-design prostheses, even in a single-level cervical TDR scenario.
Genetic Diversity Of Some Restorer Lines For Hybrid Rice Development
Authors: Kulsum MU , Hasan MJ , Begum H , Billah MM , Rahman H
Published: December 2011

Genetic divergence of thirty six restorer lines was studied through Mohalanobis’s D2 and principal component analysis for nine characters. Genotypes were grouped into five different clusters. Cluster III comprised of maximum number of genotypes (eleven) followed by cluster I and IV. The inter-cluster distance was maximum between clusters II and IV (14.064) indicating wide genetic diversity between these two clusters followed by the distance between cluster II and V (10.353), cluster III and cluster IV (8.588). The minimum inter- cluster distance was observed between cluster I and cluster III (2.885) followed by cluster I and cluster V (4.359) and cluster III and cluster V (4.825) indicating that the genotypes of these clusters were genetically close. The intra cluster distance in the entire five clusters was less, which indicated that the genotypes within the same cluster were closely related. Among the characters, number of tillers/hill, panicle length, number of filled spikelets/ panicle, spikelet fertility % and yield/plant contributed most for divergence in the studied genotypes. It indicates that these parameters can contribute more for yield in hybrid rice development.   Keywords: Rice; restorer line; genetic divergence; D2. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9226 BJAR 2011; 36(1): 21-28
Economic Analysis Of Mungbean (Vigna Radiata) Cultivation In Some Coastal Areas Of Bangladesh
Authors: Islam QM Shafiqul , Rahman MS , Hossain MA , Hossain MS
Published: December 2011

The study was conducted in two coastal mungbean growing districts, namely Noakhali and Patuakhali of Bangladesh during the period of 2008-09 with a view to estimating the technical efficiency of mungbean growers. The study revealed that mungbean production was found profitable. The benefit cost ratio (BCR) was 2.22 on full cost basis. The estimated results showed that the average level of technical efficiency among the sample farmers was 89%. This implies that given the existing technology and level of inputs, the output could be increased by 11 percent. Farmer’s education and experience had positive significant effect on mungbean production. Fifty nine percent farmers produced outputs to the maximum frontier output level. Farmers in the study area mentioned some constraints like high price of fertilizer, insecticides, severe attack of insects, etc. to the production of mungbean at farm level. Keywords: Profitability; mungbean; technical efficiency. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9227 BJAR 2011; 36(1): 29-40
Effects Of CO2 And Nitrogen Levels On Yield And Yield Attributes Of Rice Cultivars
Authors: Razzaque MA , Haque MM , Khaliq QA , Soliman ARM , Hamid A
Published: December 2011

A pot experiment was conducted at Bangbandhu Sheikh Mujibur Rahman Agricultural University during July–December of 2003 to determine the effect of rice varieties under CO2 enrichment and different levels of nitrogen supply. Plants were grown from seedling to maturity inside open top chamber under elevated CO2 (570 ±50) ppm, ambient CO2 (~360ppm) and open field condition. Cultivars responded considerably under different nitrogen levels. Increasing atmospheric CO2 directly stimulated photoynthesis and plant growth resulting in increased grain yield. Among the cultivars, BRRIdhan 39 gave the highest yield (50.82 g/plant1) at supra optimum N level and elevated CO2. Local varieties gave similar results under elevated CO2 in optimum and supra optimum N level. The lowest yield was produced by the local variety Shakkorkhora (15.09 g) under ambient CO2 with no nitrogen application. Keywords: CO2 enrichment; nitrogen level; rice cultivars DOI: http://dx.doi.org/10.3329/bjar.v36i2.9247 BJAR 2011; 36(2): 213-221
Study On The Cross Compatibility Of Some Lemon Genotypes (Citrus Limon L.)
Authors: Hossain MI , Rabbani MG
Published: December 2011

An investigation was carried out at the Department of Horticulture, Bangladesh Agricultural University, Mymensingh to examine compatible relationship among the available lemon genotypes. Seven selected genotypes of lemon were used for hybridization. Crossings were performed following diallel fashion. The results revealed that the lower percentage of fruit setting as well as seed setting in some cross combinations noticed the existence of incompatibility among the selected genotypes. The percentages of fruit setting and seed setting were higher in the cross-pollination than in the self- pollination, which was an indication of self-incompatibility. To achieve seedless fruit setting, self-incompatibility may be used successfully. Keywords: Cross compatibility; lemon genotypes. DOI: http://dx.doi.org/10.3329/bjar.v36i2.9250 BJAR 2011; 36(2): 241-246
Genetic Variability Of Some Cytoplasmic Male Sterile Lines (CMS) Of Rice (Oryza Sativa L.) Genotypes
Authors: Hasan MJ , Kulsum Umma , Rahman MH , Ali M Hazrat , Julfiquar AW
Published: December 2011

The desirable characteristics of fourteen genetically diverse CMS lines were assessed for their phenotypic acceptability, plant height (cm), days to 50% flowering. panicles per plant, stability for pollen sterility, panicle exertion rate and out crossing rate. The CMS lines viz. BRRI1A. IR 58025A. BRRI10A. BRRI9A. BRRI3A, IR 75608A, and 1132A have been found to be usable female parents for hybrid rice breeding due to their appreciable phenotypic acceptability, stable pollen sterility, panicle exertion rate and good out crossing rate. Panicle exertion rate of CMS lines had moderate heritability (38.34%) coupled with low genetic advance (2.34%) expected in the subsequent generations, that proved to be vulnerable to environmental fluctuation. The genotypic and phenotypic coefficient of variation was not remarkably varied from each other for most of the characters studied, indicated negligible environmental influence on these traits. Overall genetic correlation coefficients were higher than corresponding phenotypic correlation coefficients indicated strong relation present among the studied characters. Keywords: Genetic variability; CMS lines; rice. DOI: http://dx.doi.org/10.3329/bjar.v36i2.9253 BJAR 2011; 36(2): 263-270
Epistemic Information in Stratified M-Spaces
Authors: Burgin Mark
Published: December 2011

Information is usually related to knowledge. However, the recent development of information theory demonstrated that information is a much broader concept, being actually present in and virtually related to everything. As a result, many unknown types and kinds of information have been discovered. Nevertheless, information that acts on knowledge, bringing new and updating existing knowledge, is of primary importance to people. It is called epistemic information, which is studied in this paper based on the general theory of information and further developing its mathematical stratum. As a synthetic approach, which reveals the essence of information, organizing and encompassing all main directions in information theory, the general theory of information provides efficient means for such a study. Different types of information dynamics representation use tools of mathematical disciplines such as the theory of categories, functional analysis, mathematical logic and algebra. Here we employ algebraic structures for exploration of information and knowledge dynamics. In Introduction (Section 1), we discuss previous studies of epistemic information. Section 2 gives a compressed description of the parametric phenomenological definition of information in the general theory of information. In Section 3, anthropic information, which is received, exchanged, processed and used by people is singled out and studied based on the Componential Triune Brain model. One of the basic forms of anthropic information called epistemic information, which is related to knowledge, is analyzed in Section 4. Mathematical models of epistemic information are studied in Section 5. In Conclusion, some open problems related to epistemic information are given.
Molecular Design Properties of OxyVita Hemoglobin, a New Generation Therapeutic Oxygen Carrier: A Review
Authors: Harrington John P. , Wollocko Hanna
Published: December 2011

OxyVita Hb is a new generation hemoglobin based oxygen carrier (HBOC) produced through modification of a zero-linked polymerization mechanism using activators which incorporate cross-linked bovine tetramer hemoglobin into “super-polymeric” macromolecules (Average molecular weight = 17 MDa) for the purpose of oxygen delivery when whole blood or packed red cells are not available. This molecular design approach was generated in order to address several fundamental biochemical and physiological weaknesses of previous generations of HBOCs. Observation during pre-clinical and clinical studies provided evidence that these early generation acellular HBOCs were directly associated with loss of retention within the circulatory system, extravasation across endothelial tissue membranes due to their small molecular size leading to arterial and venous vasoconstriction with coupled increases in mean arterial pressure (MAP). The inherent increase in molecular size and structural stability of the OxyVita Hb is a direct response to addressing these serious weaknesses that have occurred during the evolution of HBOC development within the past two decades. The nature of the zero-linked synthetic route eliminates any chemical linkers remaining in the product, eliminating side reaction concerns, such as reversibility and decomposition due to weak chemical bonds, dependency on temperature and pressure, and residual toxicity.
The Role of Carotenoids in Human Skin
Authors: Darvin Maxim E. , Sterry Wolfram , Lademann Juergen , Vergou Theognosia
Published: December 2011

The human skin, as the boundary organ between the human body and the environment, is under the constant influence of free radicals (FR), both from the outside in and from the inside out. Carotenoids are known to be powerful antioxidant substances playing an essential role in the reactions of neutralization of FR (mainly reactive oxygen species ROS). Carotenoid molecules present in the tissue are capable of neutralizing several attacks of FR, especially ROS, and are then destroyed. Human skin contains carotenoids, such as α-, γ-, β-carotene, lutein, zeaxanthin, lycopene and their isomers, which serve the living cells as a protection against oxidation. Recent studies have reported the possibility to investigate carotenoids in human skin quickly and non-invasively by spectroscopic means. Results obtained from in-vivo studies on human skin have shown that carotenoids are vital components of the antioxidative protective system of the human skin and could serve as marker substances for the overall antioxidative status. Reflecting the nutritional and stress situation of volunteers, carotenoids must be administered by means of antioxidant-rich products, e.g., in the form of fruit and vegetables. Carotenoids are degraded by stress factors of any type, inter alia, sun radiation, contact with environmental hazards, illness, etc. The kinetics of the accumulation and degradation of carotenoids in the skin have been investigated.
Targeted CRM197-PEG-PEI/siRNA Complexes for Therapeutic RNAi in Glioblastoma
Authors: Höbel Sabrina , Appeldoorn Chantal C.M. , Gaillard Pieter J. , Aigner Achim
Published: December 2011

RNA interference (RNAi) allows the specific knockdown of tumor relevant genes. To induce RNAi, the delivery of small interfering RNAs (siRNAs) is of crucial importance. This is particularly challenging for their therapeutic applications in vivo. Low molecular weight branched polyethylenimine (PEI) is safe and efficient for nucleic acid delivery including small RNA molecules, based on its ability to electrostatically complex siRNA molecules, thereby protecting them from nuclease degradation. The nanoscale PEI/siRNA complexes are endocytosed by cells prior to intracellular complex release from the lysosome and cytoplasmic release of the siRNAs from the complexes. Chemical modification and ligand decoration of the complexes aim at introducing target tissue specificity and further increased efficacy of PEI-mediated siRNA delivery. CRM197 is a mutated, non-toxic diphtheria toxin (DT) that binds to the membrane-bound precursor of HB-EGF-like growth factor/diphtheria toxin receptor highly expressed in glioblastoma cells. Likewise, the growth factor pleiotrophin (PTN/HB-GAM/HARP) is overexpressed in glioblastoma and is rate limiting for tumor growth, thus representing an attractive target gene for therapeutic knockdown approaches. PEGylation of PEI was performed to reduce the surface charge, and by CRM197 coupling we prepared a modified PEI for siRNA delivery into glioblastoma cells. The novel PEI conjugates were analyzed for their complexation efficiency and optimal mixing ratios, and complexes were physicochemically characterized regarding stability, size and zeta potential. The biological activity of the complexes was confirmed in cell culture by reporter gene knockdown. For the therapeutic treatment of subcutaneous human gliobastoma xenografts in athymic nude mice, we systemically injected the modified PEI/siRNA complexes targeting PTN. Antitumor effects based on PTN knockdown demonstrated the advantage of tumor-targeted CRM197-PEG-PEI/siRNA over untargeted PEG-PEI polyplexes. Thus, we establish targeted CRM197-PEG-PEI-based complexes for siRNA delivery in vivo, and show therapeutic effects of CRM197-PEG-PEI/siRNA-mediated knockdown of PTN.
Force to Rebalance Control of HRG and Suppression of Its Errors on the Basis of FPGA
Authors: Wang Xu , Wu Wenqi , Luo Bing , Fang Zhen , Li Yun , Jiang Qingan
Published: December 2011

A novel design of force to rebalance control for a hemispherical resonator gyro (HRG) based on FPGA is demonstrated in this paper. The proposed design takes advantage of the automatic gain control loop and phase lock loop configuration in the drive mode while making full use of the quadrature control loop and rebalance control loop in controlling the oscillating dynamics in the sense mode. First, the math model of HRG with inhomogeneous damping and frequency split is theoretically analyzed. In addition, the major drift mechanisms in the HRG are described and the methods that can suppress the gyro drift are mentioned. Based on the math model and drift mechanisms suppression method, four control loops are employed to realize the manipulation of the HRG by using a FPGA circuit. The reference-phase loop and amplitude control loop are used to maintain the vibration of primary mode at its natural frequency with constant amplitude. The frequency split is readily eliminated by the quadrature loop with a DC voltage feedback from the quadrature component of the node. The secondary mode response to the angle rate input is nullified by the rebalance control loop. In order to validate the effect of the digital control of HRG, experiments are carried out with a turntable. The experimental results show that the design is suitable for the control of HRG which has good linearity scale factor and bias stability.
The insect‐pathogenic fungus Metarhizium robertsii (Clavicipitaceae) is also an endophyte that stimulates plant root development
Authors: Sasan Ramanpreet K. , Bidochka Michael J.
Published: December 2011

• Premise of the study: The soil‐inhabiting insect‐pathogenic fungus Metarhizium robertsii also colonizes plant roots endophytically, thus showing potential as a plant symbiont. Metarhizium robertsii is not randomly distributed in soils but preferentially associates with the plant rhizosphere when applied in agricultural settings. Root surface and endophytic colonization of switchgrass (Panicum virgatum) and haricot beans (Phaseolus vulgaris) by M. robertsii were examined after inoculation with fungal conidia.

• Methods: We used light and confocal microscopy to ascertain the plant endophytic association with GFP‐expressing M. robertsii. Root lengths, root hair density, and lateral roots emerged were also observed.

• Key results: Initially, M. robertsii conidia adhered to, germinated on, and colonized roots. Furthermore, plant roots treated with Metarhizium grew faster and the density of plant root hairs increased when compared with control plants. The onset of plant root hair proliferation was initiated before germination of M. robertsii on the root (within 1–2 d). Plants inoculated with M. robertsii ΔMAD2 (plant adhesin gene) took significantly longer to show root hair proliferation than the wild type. Cell free extracts of M. robertsii did not stimulate root hair proliferation. Longer‐term (60 d) associations showed that M. robertsii endophytically colonized cortical cells within bean roots. Metarhizium appeared as a mycelial aggregate within root cortical cells as well as between the intercellular spaces with no apparent damage to the plant.

• Conclusions: These results suggest that M. robertsii is not only rhizosphere competent but also displays a beneficial endophytic association with plant roots that results in the proliferation of root hairs.
Hiv-1 Tat Protein Impairs Adipogenesis and Induces the Expression and Secretion of Proinflammatory Cytokines in Human Sgbs Adipocytes
Authors: Díaz-Delfín Julieta , Domingo Pere , Wabitsch Martin , Giralt Marta , Villarroya Francesc
Published: December 2011

Background

HIV-1 Tat protein has been shown to play multiple roles in the pathogenesis of AIDS; however, there is no information currently available on its effects on adipose tissue alterations. We have studied the effects of Tat on SGBS adipocytes to gain insight on its role on the development of lipodystrophy.

Methods

SGBS preadipocytes were exposed to Tat during and after differentiation. Acquisition of adipocyte morphology, expression of gene markers of adipogenesis and inflammation, release of adipokines and cytokines to the medium, and glucose uptake were measured. The action of Tat on tumour necrosis factor (TNF)-α-regulated messenger RNA expression was determined in differentiated adipocytes. The capacity of rosiglitazone, resveratrol and parthenolide to influence the action of Tat was also assessed.

Results

Tat treatment reduced the number of SGBS preadipocytes that acquired adipocyte morphology. It also led to repression of adipogenic gene expression and induced the coordinate expression and release of proinflammatory cytokines in human adipose cells. Moreover, combined treatment with Tat and TNF-α produced an additive effect on the repression of adipocyte genes. The observed effects of Tat on gene transcription in adipocytes were due, in part, to TNF-α that was secreted as a consequence of intracellular exposure to Tat.

Conclusions

Tat impairs adipogenesis in human SGBS preadipocytes and increases the expression and release of proinflammatory cytokines. Positive crosstalk between Tat and TNF-α contributes to the anti-adipogenic and proinflammatory effects. HIV-1 Tat protein may play a role in the adipose tissue alterations that ultimately lead to lipoatrophy and systemic metabolic disturbances observed in HIV-1-infected patients.
Clinical Characteristics of Patients with Remitting Seronegative Symmetrical Synovitis with Pitting Edema Compared to Patients with Pure Polymyalgia Rheumatica
Authors: KIMURA MAKIKO , TOKUDA YASUHARU , OSHIAWA HIDETO , YOSHIDA KAZUKI , UTSUNOMIYA MASAKO , KOBAYASHI TATSUO , DESHPANDE GAUTAM A. , MATSUI KAZUO , KISHIMOTO MITSUMASA
Published: December 2011

Objective.

To compare clinical features of patients with remitting seronegative symmetrical synovitis with pitting edema (RS3PE) and patients with polymyalgia rheumatica (PMR) and to explore the purported association between RS3PE and malignancy.

Methods.

We did a retrospective chart review of patients with RS3PE and PMR treated in a community-based hospital between January 2000 and December 2009. Outcomes assessed were clinical course of disease and associated malignancies.

Results.

We identified 28 patients with RS3PE and 123 with pure PMR. All patients with RS3PE fulfilled PMR criteria as well. Age, comorbidity, erythrocyte sedimentation rate, duration and progression of symptoms, treatment response to initial low-dose steroids, and steroid complication rates were similar in both groups. Patients with RS3PE were more likely to be male (79% vs 41%; p = 0.001) and to have a history of smoking (39% vs 15%; p = 0.008) and a higher rate of depression (11% vs 2%; p = 0.044) at diagnosis. Among those with RS3PE, hip pain was less common (39% vs 74%; p = 0.001) than in the PMR group. No patients with RS3PE and 6 patients with pure PMR (4.9%) developed another rheumatological disease during followup. Seven of 9 patients (78%) with concurrent cancer presented slightly more frequently with systemic symptoms compared to patients without cancer (48%; p = 0.098), especially with fatigue (56% vs 22%; p = 0.037) and anorexia (33% vs 9.0%; p = 0.047). Despite rigorous cancer screening in patients with RS3PE, however, the rate of associated malignancy was not statistically different from that of patients with pure PMR [2 (7%) vs 7 (6%), respectively; p = 0.673].

Conclusion.

Despite evidence that RS3PE is clinically distinct from PMR, we observed characteristics, treatment response, and outcomes like those expected in pure PMR. Compared to patients with pure PMR, patients with RS3PE are more likely to be male, to be depressed, and to smoke. Contrary to earlier studies, no clear association of RS3PE with malignancy was found despite rigorous cancer screening, although clinicians should be aware that patients with concurrent cancer may manifest more systemic signs and symptoms, as well as steroid resistance.
Osteochondral Destruction in Pigmented Villonodular Synovitis During the Clinical Course
Authors: NISHIDA YOSHIHIRO , TSUKUSHI SATOSHI , NAKASHIMA HIROATSU , SUGIURA HIDESHI , YAMADA YOSHIHISA , URAKAWA HIROSHI , ARAI EISUKE , ISHIGURO NAOKI
Published: December 2011

Objective.

In pigmented villonodular synovitis (PVNS), some cases recur and progress to osteochondral destruction. The aim of our study was to clarify the occurrence of osteochondral destruction according to the location of PVNS during the clinical course.

Methods.

Seventy-two patients with PVNS (43 female, 29 male) with a mean age of 40 years (range 3–87 yrs) had been referred to our institutions. Factors influencing the occurrence of osteochondral destruction were investigated.

Results.

Mean followup was 60 months (range 12–190 mo). Adjacent bone change occurred in 24 (42%) of 57 patients, who were evaluated at the time of the first consultation. Eight (89%) of 9 patients with hip lesions initially had bone lesions, significantly more frequently than those with other lesions (p = 0.038). Duration of symptoms was significantly correlated with the occurrence of bone lesions in diffuse knee lesions (p = 0.005). During followup, patients with location in the knee had a significantly higher incidence of osteoarthritic change (73%) compared to those with foot and ankle involvement (p = 0.027). Re-operation was more frequently required for knee lesions due to the high recurrence rate (32%). Patients who required re-operation had significantly more marked osteoarthritic change in knees (p = 0.001) during followup than those who did not.

Conclusion.

For PVNS arising in knees, repeated recurrences followed by re-operation resulted in the progression of osteoarthritic change. PVNS arising in hips, feet, and ankles developed bone lesions initially, probably due to the limited volume of these joints. The indications for re-operation for recurrent knee lesions require careful consideration regarding progression of osteoarthritic change.
The Need to Better Classify and Diagnose Early and Very Early Rheumatoid Arthritis
Authors: ZEIDLER HENNING
Published: December 2011

Early rheumatoid arthritis (RA) and very early RA are major targets of research and clinical practice. Remission has become a realistic goal in the management of RA, particularly in early disease. The 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) RA classification criteria, the EULAR treatment recommendations for RA, and the EULAR recommendations for the management of early arthritis focus on early disease and translate the knowledge related to early RA into classification and management. Nevertheless, there is a need for further improvement and progress. Results from 6 recent studies are summarized, evaluating the performance of the 2010 ACR/EULAR RA classification criteria. The data show a significant risk of misclassification, and highlight that overdiagnosis and underdiagnosis may become important issues if the criteria recommend synthetic and biological disease-modifying antirheumatic drugs. Therefore, some considerations are presented on how the current problems and limitations could be overcome in clinical practice and future research. A consensus is needed to better define the early phase of RA and differentiate from other early arthritis. The possible effect of misclassification on spontaneous and drug-induced remission of early and very early RA awaits further elucidation. Such research will eventually lead to more reliable diagnostic and classification criteria for new-onset RA.
Le sens des mots : le vocabulaire du genre en Espagne
Authors: Rodríguez Sofía
Published: December 2011

Cet article dresse le bilan des études de genre menées en Espagne et revient sur les concepts-clé ayant orienté la recherche dans ce domaine. Il montre la relation entre l´évolution du féminisme théorique et l´apparition progressive d´un vocabulaire qui défini les femmes comme des sujets politiques. Si les relations de pouvoir sont l´épicentre des catégories structurant l´analyse historique, la violence, les demandes sociales et le matérialisme traversent la société civile et s’inscrivent dans l´agenda des États. L´avenir, néanmoins, s’accompagne de nouveaux défis et dialogues interculturels qui, sans aucun doute, transformeront le discours des femmes et le langage des genres au XXIe siècle.
As temperaturas intraurbanas: exemplos do Brasil e de Portugal
Authors: Amorim Margarete Cristiane de Costa , Monteiro Ana
Published: December 2011

A utilização do sensor infravermelho termal é uma técnica importante para fornecer a temperatura qualitativa da cidade, que muito pode contribuir na perspectiva do planejamento urbano, na medida em que são definidos padrões na distribuição da temperatura da superfície de acordo com o uso e a ocupação do solo. Esta pesquisa tem como objetivo analisar as diferenças de temperaturas intraurbanas por meio de imagens térmicas do satélite Landsat 7 em duas cidades de porte médio com latitudes diferentes: Porto (Portugal) e Presidente Prudente (Brasil) em episódios de verão. Os resultados mostraram que alguns locais das cidades apresentam temperaturas das superfícies extremamente elevadas contribuindo para o desconforto térmico.
Electronic Voting by Means of Digital Terrestrial Television
Authors: Caldelli Roberto , Becarelli Rudy , Filippini Francesco , Picchioni Francesco , Giorgetti Riccardo
Published: December 2011

In this paper a Digital Terrestrial Television (DTT) based voting system is presented. This electronic voting technology allows disabled users to cast their vote from home by using common well-known devices. The needed equipment are a TV set, a Set Top Box (STB) with its remote control and a telephone line. The complete infrastructure consists of an MHP (Multimedia Home Platform) application that acts as a client application, a server application that acts as a network/counting server for e-voting, and a security protocol based on asymmetric key encryption to ensure authentication and secrecy of the vote. The MHP application is broadcasted by a certified (e.g., national) TV channel that grants its originality. The user needs a smart card issued by a national authority and to sign the encrypted ballot. The voter can browse the application by acting on the STB remote control. The server application is in charge to verify user identity, to gather and store user’s encrypted ballots and finally to count votes. The communication between the client application and the server takes place by means of a secured channel (using HTTPS) while the voting operations are secured with the help of asymmetric keys encryption.
Employees’ Perceptions of Biometric Technology Adoption in E-Government
Authors: Alhussain Thamer , Drew Steve
Published: December 2011

This paper discusses an exploratory study of government employees’ perceptions of the introduction of biometric authentication at the workplace in the Kingdom of Saudi Arabia. The authors suggest that studying the factors affecting employees’ acceptance of new technology will help ease the adoption of biometric technology in other e-government applications. A combination of survey and interviews was used to collect the required data. Interviews were conducted with managers and questionnaires were given to employees from two different government organisations in Saudi Arabia to investigate the employees’ perceptions of using biometrics. The results of this study indicate a significant digital and cultural gap between the technological awareness of employees and the preferred authentication solutions promoted by management. A lack of trust in technology, its potential for misuse and management motives reflect the managers’ need to consider their responsibilities for narrowing these gaps. It was apparent that overcoming employees’ resistance is an essential issue facing biometric implementation. Based on the research the authors recommend that an awareness and orientation process about biometrics should take place before the technology is introduced into the organisation.
Investigating the Attitude of Students Towards Online Learning
Authors: Reis Zerrin Ayvaz
Published: December 2011

The evolution of Internet has provided an opportunity for offering online learning. The old online learning models are getting replaced by new e-learning models. Many universities worldwide have started offering e-learning or online learning through a variety of online learning methods. In fact, the current e-learning models are revolutionizing the instructional content delivery, learning activities, and social communication. Although online learning environments are becoming popular, there is minimal research on learners’ attitudes toward online learning environments. The purpose of this study is to explore learners’ attitudes toward online learning. Over 300 participants participated. The findings of this study of students’ perceptions and attitudes toward online learning not only will help assess pedagogical approach but also help university officials prepare Internet-based online education delivery.
Single Attestation Image for a Trusted and Scalable Grid
Authors: Deng Yuhui , Helian Na
Published: December 2011

Traditionally, Grid users are forced to trust the Grid platforms, but the users are not always regarded as trustworthy. This trust asymmetry hinders the commercializing of Grid resources. Trusted Grid is proposed to tackle this challenge by leveraging Trusted Computing (TC). However, the TC relies on a microcontroller Trusted Platform Modules (TPM) which has limited computing power and is doomed to be a system bottleneck. This paper constructs a trusted Grid as a flat ring and decentralizes the functionalities of TPM across the ring. This architecture offers a single attestation image which provides a transparent attestation to a scalable, large-scale, and dynamic trusted Grid. The architecture also significantly reduces the frequency of attestations, thus alleviating the TPM bottleneck. Furthermore, the architecture can avoid the potential system bottleneck and single point of failure of the centralized architecture or the root node of the hierarchical architecture.
Road Traffic Parameters Estimation by Dynamic Scene Analysis
Authors: Mohana H. S. , Ashwathakumar M.
Published: December 2011

Traffic congestion and violation of traffic rules are very common in most of the road transport system. Continuous monitoring is becoming difficult. To improve the quality of road transport monitoring and control, the best possible alternative is machine vision. In this review, several works by researchers on traffic analysis are detailed, studied and reviewed critically for the purpose. Further, an attempt is made to classify the different road traffic analysis approaches available in the literature. Classification is based on principle used, algorithm adopted, techniques used, technology behind and other special considerations of the researchers.
Fuzzy Allocation of Fine-Grained Compute Resources for Grid Data Streaming Applications
Authors: Zhang Wen , Cao Junwei , Zhong Yisheng , Liu Lianchen , Wu Cheng
Published: December 2011

Fine-grained allocation of compute resources, in terms of configurable clock speed of virtual machines, is essential for processing efficiency and resource utilization of data streaming applications. For a data streaming application, its processing speed is expected to approach the allocated bandwidth as much as possible. Automatic control technology is a feasible solution, but the plant model is hard to be derived. In relation to the model free characteristic, a fuzzy logic controller is designed with several simple yet robust rules. Performance of this controller is verified to out-perform classic controllers in response rapidness and less oscillation. An empirical formula on tuning an essential parameter is obtained to achieve better performance.
US Cities and Social Networking
Authors: Northrop Alana
Published: December 2011

This chapter presents the results of a random study of US cities’ and mayors’ uses of five social networking features: Facebook, MySpace, YouTube, Twitter, and LinkedIn as well as city use of online surveys. Data from a random sample of fifty cities stratified on population indicates that only Facebook is used by a majority of cities’ websites and mayors. The lower level of use of Twitter and YouTube and less than universal use of Facebook is complemented by a very low level of citizen followers, viewers, and friends. Most cities also do not use online surveys on their websites. This low use likely just reflects government’s tendency to follow trends rather than lead and is not a statement about cities’ lack of citizen orientation. It also appears to be a reflection of smaller cities adopting information technologies more slowly than larger cities when we compare 2010 data with that from early in 2011. Nonetheless, the result is that the potential positive opportunities for cities and mayors to connect and converse with citizens via Web 2.0 are under-realized if we just look at the Internet social networking face presented, and if cities do not get on the Web 2.0 bandwagon in this regard, citizens, especially younger ones, may feel that it is another example of government being out of touch with what is happening in the “real” world.
Open Source, Crowdsourcing, and Public Engagement
Authors: Liu Helen K.
Published: December 2011

This chapter is an investigation of open source, crowdsourcing, and public engagement in the public and nonprofit sectors through four cases: (1) Changemakers competitions, (2) Peer to Patent in the U.S., (3) Future Melbourne 2020 in Australia, and (4) Idea Box in Japan. Macintosh’s (2004) case analytical framework is adopted to systematically document the four cases for comparisons. From the literature three components are identified to understand the open source and crowdsourcing models: initiator, mechanism for information selection, and beneficiary. Three components are used to examine how governments or nonprofits adopt the open source model or crowdsourcing model to facilitate public engagement. The conclusion is that different designs of the projects might lead to different scales of public engagement, defined by Savar & Denhardt (2010). Finally, some potential issues and challenges of implementing the open source and crowdsourcing models to facilitate engagement in public affairs are discussed.
The Influence of Cognitive Styles on Learners’ Performance in e-Learning
Authors: Zheng Robert Z.
Published: December 2011

This chapter focused the influence of cognitive styles on learners’ performance in e-Learning. The author examined the existing practice of style matching where instructional conditions were matched with learners’ cognitive styles and found that style matching did not necessarily provide learning gains for learners with different cognitive styles. Instead, he proposed ability building as an effective approach to improve learners’ learning. Following the same line, the author further examined the relationship between cognitive styles and instructional situations where situated learning was implemented. The results revealed that instructional situations can significantly influence learners’ learning in complex learning and that cognitive style was not, as viewed by many people, a linear relationship between style and performance. Instead, it displayed multi-dimensional relationships with variables related to e-Learning. The author thus suggested that cognitive style should be examined in a broader manner where variables related to e-Learning be considered simultaneously.
Digital Games
Authors: Özkan-Czerkawski Betül
Published: December 2011

Digital games and simulations are playing an important role in younger generations’ lives. Their adoption to e-Learning environments, however, is rather slow because educators are reluctant to change the way they teach. This chapter starts with a brief discussion of game and simulation terminology, including serious games, game-based learning, and game genres. It continues with a review of the current status of educational games and simulations being used in higher education institutions. Important case studies are provided to present examples to the higher education faculty. Finally, a discussion of teaching strategies, instructional design processes, and assessment issues for effective digital game incorporation in e-Learning is included.
A Case Study of Social Interaction on ANGEL and Student Authoring Skills
Authors: Guo Ruth Xiaoqing
Published: December 2011

This case study examined a constructivist approach to creating an interactive learning environment on ANGEL for graduate students in a course: EDC 604—Authoring for Educators. The course curriculum was designed to help students construct knowledge to develop professional Websites. However, the class time was insufficient to meet the student learning needs and course objectives. The social interaction on ANGEL provided flexible time and space for participants to discuss the issues important to them. Findings revealed that practical action research combined with social interaction shed light on important issues of professional development through reflection on practice. The constructivist approach provided an interaction of two important sets of learning conditions: Internal and external levels for student cognitive development in authoring skills. Data were analyzed using a grounded theory approach. This study also identified issues for further research: The importance of curriculum design to meet students’ needs, the effect of digital divide, and how student attitude impacts learning.
Intentional Communities of Practice, the Challenge of Interactivity
Authors: Powell Aaron Wiatt
Published: December 2011

This chapter examines the support of social interaction in a cooperative, situated online learning environment, and the cultural barriers that hinder such intention and interactivity. The findings of a literature review suggest that the greatest challenge to intentional Community of Practice (CoP) is a sense of interdependence among CoP members, the authenticity of the practice or purpose, and a trajectory for the CoP’s future. This case study attends to these issues with a cohort of practicing teachers. It explores an initiative to nurture CoP with cooperative projects and with the support of an online community portal. The case challenges CoP theory from an intentional or instructional standpoint, and informs design and technology in support of CoP.
Embedded Librarians
Authors: Bonnand Sheila , Hansen Mary Anne
Published: December 2011

This chapter reports on one academic library’s experiences with expanding instructional services by adding synchronous library instruction to better serve its online students and faculty located across the globe. Web conferencing software allows librarians to provide interactive, high-touch library instruction for online students equivalent to the experience of students in traditional face-to-face courses. While providing this real-time instruction on library resources and research skills, librarians are embedding themselves in online programs, becoming more readily accessible to online and distance students. By meeting the changing needs of academic library users wherever they are, librarians are reaffirming their integral role and relevance as partners in the educational endeavor.
VANET Authentication Using Trust Distribution in a Clustered Environment
Authors: Sivagurunathan S. , Subathra P.
Published: December 2011

Security is a prime concern in providing communication between vehicles in a Vehicular Ad-Hoc Network (VANET), where they share information among themselves and nearby fixed equipments. Unlike wired networks, the unique characteristics of Vehicular Ad hoc Networks (VANETs) pose a number of non-trivial challenges to security design. This chapter presents a threshold security mechanism with a mobility based clustering for Inter Vehicle Communication (IVC). Nodes that have similar moving pattern are grouped into a cluster. Unlike other clustering algorithms, it takes the moving pattern of the vehicles into consideration along with the driver’s intention. The stability of clusters is estimated based on relative mobility of cluster members. A threshold cryptographic scheme is employed on top of the clusters to protect routing information and data traffic. To ensure distributed trust in the clustered environment, the private key (k) is divided into n pieces in such a way that k is easily reconstruct able from any p number of pieces. Even complete knowledge of (p-1) pieces reveals absolutely no information about k.
Scalable P2P Video Streaming
Authors: Alhaisoni Majed , Ghanbari Mohammed , Liotta Antonio
Published: December 2011

P2P networks are a technology able to deliver real time and video-on-demand services over IP networks. Layered video coding techniques are being introduced due to their ability to deliver streams at different scales (temporal, spatial and SNR) that solve the heterogeneity problem. This eases transmission in the case of limited bandwidth, as the devices can pick and decode the minimum bit rate base layer. Existing work examines layered video in client-server scenarios. In contrast, this paper analyzes scalable coding H.264/SVC over P2P networks based on an SNR-temporal Codec. Due to the interdependency between the different SVC layers, issues of reliability and quality of experience arise unless proper measures are taken to protect the base layer. The authors explore the effectiveness of a combination of P2P strategies, for example, hybrid P2P architecture, P2P locality, and P2P redundancy, to assess the viability and benefits of scalable video coding over P2P. The resulting performance is compared with a state-of-the-art P2P TV platform.
A Cache Replacement Policy for Location Dependent Data in Mobile Environments
Authors: Jane. F Mary Magdalene , Nadarajan R , Safar Maytham
Published: December 2011

Cache hit ratio is employed as the primary performance metric where the higher the cache hit ratio, the higher the local data availability, lower uplink and downlink costs and less battery consumption. The experimental results show that the proposed replacement scheme is effective when the user preference is considered and the policy significantly outperforms the conventional replacement policies.
Use of Technology to Motivate Students
Authors: Verma Deepak
Published: December 2011

A middle school teacher proposed that since students these days are more at ease with technology due to the excessive use of technology gadgets in their lives, why not make the best use of technology by way of electronic whiteboards to engage students? This brought about some changes in this inner city school which had failed the state Annual Yearly Progress (AYP) report more than once. However, was the sudden surge in student motivation the result of the novelty effect or the Hawthorn effect? And might that surge in student motivation soon fade away?
“No/Low Paper” Policy and Equipment Upkeep
Authors: Martinez Alicia
Published: December 2011

In an effort to control paper supplies and budget, an elementary school initiated a “No/Low Paper Policy.” Under this policy, teachers are encouraged to use the technology available in classrooms instead of worksheets, and teachers were assigned quotas and pin numbers to discourage excessive paper usage. Despite the forward thinking attitude of the school, the campus technology specialist continues to struggle with being heard by campus and district administration on issues dealing with the purchase and upkeep of technology.
The Laptop Tracking Plan
Authors: Munks Jessie
Published: December 2011

A school was able to receive the “Technology for All” grant to issue a large number of laptop computers for students to check out and use at home. A policy for checking out the laptops was developed that included a software utility to keep track of the amount of time students may keep the laptop, the implantation of antitheft tracking software to minimize loss, the maintenance plan of the laptops, how they were to be insured, and other information. Later on, the school principal had to devise a new plan so that the laptop checkout policy would not escalate into damages and possible lawsuits.