bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of lentinan on the gene expression of major ion channels in T lymphocytes isolated from mice exposed to chronic radiation
Authors: Fu Qing-Jie , Wang Yong , Liu Ying-Hua , Lin Ping-Ping , Wang Pei-Pei , Liu Jiao , Zhang Bin , Li Ming-Chun
Published: July 2013

It is known that Kv1.3, KCa3.1, CRAC, TRPM7, and Clswell are five important
ion channels in T lymphocytes. To investigate the mechanism underlying the
protective effects of lentinan against T lymphocytes injury induced by
chronic radiation in mice, we determined the expression profiles of Kv1.3,
KCa3.1, Orai1, STIM1, TRPM7, and Clswell genes. Mice were injected with
different concentrations of lentinan before exposure to 60Co g-ray. Total RNA
was then extracted from T lymphocytes in murine spleen. The Real time-PCR was
per- formed to detect the expression levels of Kv1.3, KCa3.1, Orai1, STIM1,
TRPM7, and Clswell genes. The results show that, out of the six ion channels
gene expression detected in the present study, only Kv1.3 and Orai1 were
altered by lentinan in mice under chronic radiation stress. Kv1.3 and Orai1
expression were significantly elevated in T-lymphocytes isolated from
irradiated mice, and were normalized by lentinan treatment. Our results
suggest that that Kv1.3 and Orai1 channels may mediate the anti-radiation
effects of lentinan.
Radiation-mediated induction of apoptotic cell death in rat hippocampus
Authors: Velickovic Natasa , Djordjevic Ana , Drakulic Dunja , Secerov Bojana , Grkovic Ivana , Milosevic Maja , Horvat Anica
Published: July 2013

Ionizing radiation is commonly used in the treatment of brain tumors but it
can impair cognitive functions, such as learning and memory. Since cognitive
dysfunctions are predominantly result of cell death by apoptosis in
hippocampal cells, in this study we analyzed acute effects of cranial
gamma-irradiation (10 Gy) on expression of proapoptotic molecules (p53, Bax)
and antiapoptotic molecule Bcl-2, as well as caspase-3 activation and
cytochrome c redistribution in the hippocampus of young rats. The selected
regimen of irradiation resembles the established animal model for childhood
prophylactic cranial radiotherapy. Our results demonstrated that p53 mRNA
expression was unchanged after irradiation, while induction of p53 protein
was rapid. In parallel, Bax mRNA and protein levels were also increased
following irradiation, whereas Bcl-2 expression was not changed during the
examined post-irradiation period. These changes were accompanied with early
hallmarks of apoptosis, such as increased cytochrome c release and stimulated
activation of caspase-3. Overall, this study demonstrates that cranial
irradiation is associated with the augmented apoptotic pathway in the rat
hippocampus, which could be related to the cognitive decline observed in
patients after prophylactic cranial radiotherapy, but also opens perspective
in finding radioprotectors that can mitigate radiation injury of normal brain
tissue.
The effect of radioprotectors protection ability in pheasants after alimentary radio-contamination with 137Cs
Authors: Vicentijevic Mihajlo , Pantelic Gordana , Vukovic Dubravka , Vukovic Vujadin , Mitrovic Branislava , Zivanov Dragan
Published: July 2013

Considering that previous studies were mainly focused on a protection of
domestic animals from alimentary Cs-contamination, the objective of the
present study was to investigate the possibilities of ammonium - iron (III)
hexacyanoferrate (II) - AFCF and clinoptilolite as radioprotectors. Pheasants
of species Phasianus colchicus were used as trial animals. The total number
of 2 -month old pheasants was 100. The pheasants were divided into five
groups; each group was contaminated with 750 Bq of 137Cs per bird in a single
experiment. The experiment consisted of 5 phases during which the animals
were given AFCF (0.2 g) and clinoptilolite (2 g) either in water solution or
mixed with food, according to the phase. The level of contamination was
determined by gamma - spectrometry in breast meat, leg meat, liver and
gizzard. The results show that the best protection effect was obtained when
AFCF is used in the water solution i. e. 92.7%; while AFCF mixing with food
demonstrated 74.9% of protection; clinoptilolite proved less protective with
69.3% - in the water solution, and 50.5% when mixed with food.
Dental anomaly pattern (DAP): Agenesis of mandibular second premolar, distal angulation of its antimere and delayed tooth formation
Authors: Navarro Joana , Cavaller Maria , Luque Estela , Tobella Maria Luisa , Rivera Alejandro
Published: July 2013

Objective:

To test the null hypotheses that children with unilateral agenesis of the mandibular second premolar (MnP2) do not show (1) greater distal angulation of the unerupted antimere and (2) delayed tooth formation compared with children without agenesis.

Materials and Methods:

Panoramic radiographs of 38 patients with unilateral aplasia of MnP2 were retrospectively examined and compared to a non-agenesic control group of 82 patients. Ages ranged from 8 to 15 years. Contralateral mandibular deciduous second molars were present for all participants. Each unerupted MnP2 was traced, and its developmental stage and angulation were recorded (measured with the distal angle and the premolar-molar angle). Dental age was evaluated using the Haavikko method. Student's t-test was performed to identify significant differences between the compared groups. The significance level for statistical testing was set at P < .05.

Results:

The results indicated a 9.5° decrease in the distal angle and a 13.2° increase in the premolar-molar angle for the unerupted MnP2 in the agenesis sample. This was a highly statistically significant difference (P < .001 and P < .0001, respectively) compared with the MnP2 inclinations in the control sample. The delay in dental age was significantly greater in patients with agenesis (2.1 years) compared with the delay in the control group (1.5 years) (P < .001).

Conclusion:

Both null hypotheses are rejected. The results of this study statistically support the hypothesis that aplasia of MnP2, distally displaced MnP2s, and delayed tooth formation are part of a genetically related pattern of dental anomalies.
Mini-implant stability at the initial healing period: A clinical pilot study
Authors: Nienkemper Manuel , Wilmes Benedict , Pauls Alexander , Drescher Dieter
Published: July 2013

Objective:

To evaluate the changes of mini-implant stability over the initial healing period in humans.

Material and Methods:

A sample of 19 consecutively treated patients (mean age 15.5 ± 7.3 years) was examined. In each patient, a mini-implant of a size of 2 × 9 mm was inserted into the anterior palate. Implant stability was assessed using resonance frequency analysis (RFA) immediately after insertion (T0), 2 weeks later (T1), 4 weeks later (T2), and 6 weeks later (T3). Insertion depth (ID) and the maximum insertion torque (IT) were measured. Data were tested for correlations between RFA, ID, and IT. All RFA values were tested for statistically significant differences between the different times.

Results:

The mean ID was 7.5 ± 0.6 mm, and the mean IT was 16.8 ± 0.6 Ncm. A correlation was found between RFA and ID (r  =  .726, P < .0001), whereas no correlations between RFA and IT or between IT and ID were observed. From T0 to T1, the stability (36.1 ± 6.1 implant stability quotient [ISQ]) decreased nonsignificantly by 4.9 ± 6.1 ISQ values (P > .05). Between T1 and T2, the stability decreased highly significantly (P < .001) by 7.9 ± 5.9 ISQ values. From T2 on, RFA remained nearly unchanged (−1.7 ± 3.5 ISQ; P > .05).

Conclusions:

Mini-implant stability is subject to changes during the healing process. During weeks 3 and 4, a significant decrease of the stability was observed. After 4 weeks, the stability did not change significantly.
Polyhydrated Ionogen with MgBr2 Accelerates in vitro Respiratory Epithelial Healing
Authors: DePoortere David , Chen Bei , Cohen Noam A.
Published: July 2013

Background

Remucoslization of the sinonasal cavity after sinus surgery is critical for successful outcomes. Recently, a novel antiprotease and antifibroblast compound, polyhydrated ionogen (PHI) with MgBr2, showed improved wound healing in a rabbit maxillary sinus mucosal wound model. We set out to determine if this effect was reproducible in an in vitro respiratory epithelial culture system.

Methods

Fully differentiated mature murine nasal septal air–liquid interface cultures were injured by creating a full-thickness 400-mM-wide scratch through the monolayer. Cultures were then treated with nothing, saline, or PHI with MgBr2for 1 hour on the apical surface. Twenty-four hours after the injury cultures were fixed and processed for immunofluorescence with type IV beta-tubulin and Hoechst stain.

Results

Initial injury resulted in a wound of 394 micromolar (377–411 micromoler; 95% CI; n = 8). After 24 hours with no intervention the wound closed to 161 micromolar (138–184 micromolar; 95% CI; n = 9) and treatment with saline resulted in a residual gap of 88 micromolar (60–116 micromolar; 95% CI; n = 9; p < 0.05) and treatment with PHI with MgBr2 resulted in a gap of only 30 micromolar (14–46 micromolar; 95% CI; n = 9; p < 0.05).

Conclusion

Poor healing of the sinonasal mucosa after surgery with loss of ciliary function results in adverse clinical outcomes. In an in vitro sinonasal respiratory epithelial injury model, a one-time treatment with PHI with MgBr2 showed significantly improved wound healing compared with saline or nothing. This is a viable model to further investigate the mechanism by which PHI with MgBr2 improves sinonasal remucosolization.
Intestinal Helminthiasis in Bangladesh, the Clinical Features
Authors: Ahmed S
Published: July 2013

Bangladesh Journal of Medical Science Vol.1(4) 1994 pp.20-33
Sustained virological response after treatment in patients with chronic hepatitis C infection - a five year follow up
Authors: Rahman MZ , Ahmed DS , Masud H , Parveen S , Rahman MA , Chowdhury MS , Barua R , Ishaque SM
Published: July 2013

Peginterferon ?-2a and ribavirin combination therapy achieves a sustained virological response (SVR) in patients with chronic hepatitis C. Little is know about long-term durability of hepatitis C virus  Ribonucleic acid (HCV-RNA) negativity in patient treated with pegylated interferon and ribavirin therapy. Aim of this study was to evaluate the durability of virologic response in patients with SVR to anti-viral therapy treated at our centre. A total of 52 patients with chronic hepatitis C virus infection who had obtained SVR after Peginterferon ?-2a and ribavirin combination therapy were followed up to 5 years with annual HCV-RNA testing. During this follow up period, 4 of 52 patients with initial SVR developed late relapse of hepatitis C virus infection. Relapse was more common in patients who has cirrhosis (3/6 [50%]) vs (1/46 [2.17%]) without cirrhosis. In conclusion, SVR is durable in most patients, but some patients do have late relapse; long term follow up may be particularly important in a subset of patients with hepatitis C virus infection who have liver cirrhosis. DOI: http://dx.doi.org/10.3329/bmrcb.v39i1.15791 Bangladesh Med Res Counc Bull 2013; 39: 11-13
Leptin to adiponectin ratio in preeclampsia
Authors: Khosrowbeygi A , Ahmadvand H
Published: July 2013

The aim of the present study was to assess leptin/adiponectin ratio in preeclamptic patients compared with normal pregnant women. A cross-sectional study was designed. The study population consisted of 30 preeclamptic patients and 30 healthy pregnant women. Serum levels of total leptin and adiponectin were assessed using commercially available enzyme-linked immunosorbent assay methods. The oneway ANOVA and Students t tests and Pearsons correlation analysis were used for statistical calculations. Levels of leptin and adiponectin were also adjusted for BMI. A p-value <0.05 was considered statistically significant. The leptin/adiponectin ratio was increased significantly in preeclamptic patients. The leptin/adiponectin ratio was significantly higher in severe preeclamptic patient than in mild preeclampsia. Adjusted leptin/adiponectin ratio was also significantly increased in preeclamptic patients than in normal pregnant women. The findings of the present study suggest that the leptin/adiponectin ratio was increased in preeclamsia and imbalance between the adipocytokines could be involved in the pathogenesis of preeclampsia. DOI: http://dx.doi.org/10.3329/bmrcb.v39i1.15805 Bangladesh Med Res Counc Bull 2013; 39: 18-21
Adverse outcome of methotrexate and mini pulse betamethasone in the treatment of lichen planus
Authors: Hazra SC , Choudhury AM , Asaduzzaman ATM , Paul HK
Published: July 2013

The objectives of this study were to compare the adverse outcome of methotrexate and mini pulse betamethasone therapy in the treatment of lichen planus. It was a clinical trial conducted in the department of Dermatology and Venereology, Bangabandhu Sheikh Mujib Medical University, Dhaka, from January 2009 to December 2010. Forty four patients of lichen planus were included in the study. Patients in Group-A, (n=23) were treated with methotrexate (10 mg) single morning dose and group-B (n=21) were treated with mini pulse betamethasone (5mg) single morning dose on 2 consecutive days during the period of 12 weeks. Adverse outcomes were measured by clinical examination and laboratory investigations during follow up visits. Anemia 3(14.2%) and edema 12(57.1%) developed in group-B but none in group-A. In group-B, dyspepsia 15(71.4%), acne 10(47.6%), mooning face 8(38.1%), striae 8(38.1%) and hypertrichosis 4(19.0%) developed but none in group-A. Intermittent diarrhoea, headache, nausea and fatigue complained in both groups of patients but the percentage of complaints was higher amog group-B compared to group-A. Menstrual abnormality developed in group-B 5(71.4%) but none in group-A. Laboratory investigations showed abnormality in platelet count and SGPT in group-A but none in group-B. The adverse effects of methotrexate on haematological parameter and liver functions were mild and could be prevented by reducing the dose but the adverse effects of betamethasone were unavoidable. The overall adverse effects were less in group-A than group-B. Therefore, methotrexate can be used as an alternative safer option for the treatment of lichen planus. DOI: http://dx.doi.org/10.3329/bmrcb.v39i1.15806 Bangladesh Med Res Counc Bull 2013; 39: 22-27
Deleuzian Dragons: Thinking Chinese Strategic Spatial Planning with Gilles Deleuze
Authors: Hillier Jean , Cao Kang
Published: July 2013

As symbols of adaptability and transformation, together with qualities of vigilance and intelligence, we argue the relevance of dragons for spatial planning in China. We develop a metaphorical concept – the green dragon – for grasping the condition of contemporary Chinese societies and for facilitating the development of theories and practices of spatial planning which are able to face the challenges of rapid change. We ask Chinese scholars and spatial planners to liberate Deleuzian potential for strategic spatial planning in a ‘becoming-between, coming-together’ of concepts which can effectively make a difference in the world. Having outlined what we regard as key transversals or diagonals between our reading of Gilles Deleuze and aspects of Chinese philosophy, we then offer the metaphor of strategic spatial planning as Chinese literati landscape painting. This is a form of painting which rejects the idea of the world being supremely organised from a particular point of view, preferring to paint immanence and transformation. Chinese literati landscape paintings, like philosophy and strategic spatial planning, ‘look only at the movements’. We conclude that connections between what concepts of Chinese philosophy and those of Gilles Deleuze can do, suggest that in China, a conception of strategic spatial planning as metaphorical green dragon may offer academics and planning practitioners a transverse way to relate the legacies of past philosophies and current thinking.
The Role of AKT/mTOR Pathway in Stress Response to UV-Irradiation: Implication in Skin Carcinogenesis by Regulation of Apoptosis, Autophagy and Senescence
Authors: Strozyk Elwira , Kulms Dagmar
Published: July 2013

Induction of DNA damage by UVB and UVA radiation may generate mutations and genomic instability leading to carcinogenesis. Therefore, skin cells being repeatedly exposed to ultraviolet (UV) light have acquired multilayered protective mechanisms to avoid malignant transformation. Besides extensive DNA repair mechanisms, the damaged skin cells can be eliminated by induction of apoptosis, which is mediated through the action of tumor suppressor p53. In order to prevent the excessive loss of skin cells and to maintain the skin barrier function, apoptotic pathways are counteracted by anti-apoptotic signaling including the AKT/mTOR pathway. However, AKT/mTOR not only prevents cell death, but is also active in cell cycle transition and hyper-proliferation, thereby also counteracting p53. In turn, AKT/mTOR is tuned down by the negative regulators being controlled by the p53. This inhibition of AKT/mTOR, in combination with transactivation of damage-regulated autophagy modulators, guides the p53-mediated elimination of damaged cellular components by autophagic clearance. Alternatively, p53 irreversibly blocks cell cycle progression to prevent AKT/mTOR-driven proliferation, thereby inducing premature senescence. Conclusively, AKT/mTOR via an extensive cross talk with p53 influences the UV response in the skin with no black and white scenario deciding over death or survival.
Identification and Phylogenetic Analysis of a CC-NBS-LRR Encoding Gene Assigned on Chromosome 7B of Wheat
Authors: Gong Caiyan , Cao Shuanghe , Fan Renchun , Wei Bo , Chen Guiping , Wang Xianping , Li Yiwen , Zhang Xiangqi
Published: July 2013

Hexaploid wheat displays limited genetic variation. As a direct A and B genome donor of hexaploid wheat, tetraploid wheat represents an important gene pool for cultivated bread wheat. Many disease resistant genes express conserved domains of the nucleotide-binding site and leucine-rich repeats (NBS-LRR). In this study, we isolated a CC-NBS-LRR gene locating on chromosome 7B from durum wheat variety Italy 363, and designated it TdRGA-7Ba. Its open reading frame was 4014 bp, encoding a 1337 amino acid protein with a complete NBS domain and 18 LRR repeats, sharing 44.7% identity with the PM3B protein. TdRGA-7Ba expression was continuously seen at low levels and was highest in leaves. TdRGA-7Ba has another allele TdRGA-7Bb with a 4 bp deletion at position +1892 in other cultivars of tetraploid wheat. In Ae. speltoides, as a B genome progenitor, both TdRGA-7Ba and TdRGA-7Bb were detected. In all six species of hexaploid wheats (AABBDD), only TdRGA-7Bb existed. Phylogenic analysis showed that all TdRGA-7Bb type genes were grouped in one sub-branch. We speculate that TdRGA-7Bb was derived from a TdRGA-7Ba mutation, and it happened in Ae. speltoides. Both types of TdRGA-7B participated in tetraploid wheat formation. However, only the TdRGA-7Bb was retained in hexaploid wheat.
Long Non-Coding RNAs in Haematological Malignancies
Authors: Garitano-Trojaola Andoni , Agirre Xabier , Prósper Felipe , Fortes Puri
Published: July 2013

Long non-coding RNAs (lncRNAs) are functional RNAs longer than 200 nucleotides in length. LncRNAs are as diverse as mRNAs and they normally share the same biosynthetic machinery based on RNA polymerase II, splicing and polyadenylation. However, lncRNAs have low coding potential. Compared to mRNAs, lncRNAs are preferentially nuclear, more tissue specific and expressed at lower levels. Most of the lncRNAs described to date modulate the expression of specific genes by guiding chromatin remodelling factors; inducing chromosomal loopings; affecting transcription, splicing, translation or mRNA stability; or serving as scaffolds for the organization of cellular structures. They can function in cis, cotranscriptionally, or in trans, acting as decoys, scaffolds or guides. These functions seem essential to allow cell differentiation and growth. In fact, many lncRNAs have been shown to exert oncogenic or tumor suppressor properties in several cancers including haematological malignancies. In this review, we summarize what is known about lncRNAs, the mechanisms for their regulation in cancer and their role in leukemogenesis, lymphomagenesis and hematopoiesis. Furthermore, we discuss the potential of lncRNAs in diagnosis, prognosis and therapy in cancer, with special attention to haematological malignancies.
Holographic Quantitative Structure-Activity Relationships of Tryptamine Derivatives at NMDA, 5HT1A and 5HT2A Receptors
Authors: Palangsuntikul Rungtiva , Berner Heinz , Berger Michael , Wolschann Peter
Published: July 2013

Tryptamine derivatives (Ts) were found to inhibit the binding of [3H]MK-801, [3H]ketanserin and [3H]8-OH-DPAT to rat brain membranes. [3H]MK-801 labels the NMDA (N-methyl-D-aspartate) receptor, a ionotropic glutamate receptor which controls synaptic plasticity and memory function in the brain, whereas [3H]ketanserin and [3H]8-OH-DPAT label 5HT2A and 5HT1A receptors, respectively. The inhibitory potencies of 64 Ts (as given by IC50 values) were correlated with their structural properties by using the Holographic QSAR procedure (HQSAR). This method uses structural fragments and connectivities as descriptors which were encoded in a hologram thus avoiding the usual problems with conformation and alignment of the structures. Four correlation equations with high predictive ability and appropriate statistical test values could be established. The results are visualized by generation of maps reflecting the contribution of individual structural parts to the biological activities.
An Advanced Temporal Credential-Based Security Scheme with Mutual Authentication and Key Agreement for Wireless Sensor Networks
Authors: Li Chun-Ta , Weng Chi-Yao , Lee Cheng-Chi
Published: July 2013

Wireless sensor networks (WSNs) can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs). Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.’s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users’ attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.’s authentication scheme are left unchanged.
Cement and concrete porosity measurement
Authors: Lichtner B. , Hundt J.
Published: July 2013

Not available
Cement strength increment by additional ettringite formation
Authors: Simeonov J. , Djabarov N.
Published: July 2013

Not available
Method for the analytical determination of total sulphur sulphates contents in concrete and aggregates; and remarks on the need to separate from the total permissible sulphur the proportion due to sulphates
Authors: Gomá F.
Published: July 2013

No available
Impressions about the Soviet Union research centers in the field of cement technology
Authors: Calleja J.
Published: July 2013

Not available
Conclusions of the 2nd. General Assembly of the Instituto Eduardo Torroja of Construction and Cement
Authors: Editorial Equipo
Published: July 2013

Not available
Study of transformations of hydrated high alumina cement by means of ray diffraction, infrared spectroscopy and thermal analysis. Influence of carbon anhydride, temperature, humidity and the addition of powdered limestone (continuation)
Authors: Vázquez T. , Triviño F. , Ruiz de Gauna A.
Published: July 2013

Not available
Testing procedure to determine the water absorption capacity of bricks (H2T 2/75c)
Authors: García Verduch Antonio
Published: July 2013

Not available
Use of «Melment» in plants making prefabricated units
Authors: Nitsche J . W.
Published: July 2013

Not available
Silicon gel as puzzolane standard: its energetic activity and limitations.
Authors: De Luxán M. Pilar , Vázquez Tomás
Published: July 2013

Not available
Contribución al estudio de los reacciones de hidratación del cemento portland, por espectroscopio infrarroja Estudio de las fases sintetizadas del clínker de cemento portland
Authors: Vázquez Moreno Tomás , Gaspar Tebar Demetrio
Published: July 2013

Not available
Determinación del contenido de escorias en los cementos siderúrgicos
Authors: Gaspar-Tébar Demetrio
Published: July 2013

Not available
Relaciones entre lo carbonatación del cemento portland, el grado de cocción del clínker y algunos fenómenos expansivos en el ensayo de autoclave
Authors: Ruiz de Gauna A.
Published: July 2013

Not avialble
Insights from Experimental Research on Distributed Channel Assignment in Wireless Testbeds
Authors: Juraschek Felix , Günes Mesut , Philipp Matthias , Blywis Bastian
Published: July 2013

This article presents the DES-Chan framework for experimental research on distributed channel assignment algorithms in wireless mesh testbeds. The implementation process of channel assignment algorithms is a difficult task for the researcher since common operating systems do not support channel assignment algorithms. DES-Chan provides a set of common services required by distributed channel assignment algorithms and eases the implementation effort. The results of experiments to measure the channel characteristics in terms of intra-path and inter-path interference according to the channel distance on the DES-Testbed are also presented. The DES-Testbed is a multi-radio WMN with more than 100 nodes located on the campus of the Freie Universität Berlin. These measurements are an important input to validate common assumptions of WMNs and derive more realistic, measurement-based interference models in contrast to simplified heuristics.
BER Fairness and PAPR Study of Interleaved OFDMA System
Authors: Ahmed Sabbir , Kawai Makoto
Published: July 2013

For an OFDMA system, the role of interleavers is analyzed to ensure fairness of BER performance among the active users and investigate their respective PAPR properties. In this paper, the authors consider a generic system and show that for a slowly changing multipath channel, individual user’s BER performance can vary, implying that the propagation channel effect is unfairly distributed on the users. Applying different types of frequency interleaving mechanisms, the authors demonstrate that random interleaving can ensure BER fairness on an individual user basis but the associated system overhead for de-interleaving is very high. In this context, the authors introduce the application of cyclically shifted random interleaver and demonstrate its effectiveness in achieving BER fairness (dispersion in individual users BER reduced by 94% compared to no interleaving at 20dB SNR) with little system overhead. The authors also explore the comparative performance of different interleavers for scenarios with varying number of total subcarriers and subcarriers per user. Based on the scenario specific results, the authors conclude that for a heavily loaded system, i.e., relatively low number of subcarriers per user, cyclically shifted random interleavers can effectively ensure uniform performance among active users with reduced system complexity and manageable PAPR.
Lifetime Maximization in Wireless Sensor Networks
Authors: Katiyar Vivek , Chand Narottam , Soni Surender
Published: July 2013

One of the fundamental requirements in wireless sensor networks (WSNs) is to prolong the lifetime of sensor nodes by minimizing the energy consumption. The information about the energy status of sensor nodes can be used to notify the base station about energy depletion in any part of the network. An energy map of WSN can be constructed with available remaining energy at sensor nodes. The energy map can increase the lifetime of sensor networks by adaptive clustering, energy centric routing, data aggregation, and so forth. In this paper, the authors describe use of energy map techniques for WSNs and summarize the applications in routing, aggregation, clustering, data dissemination, and so forth. The authors also present an energy map construction algorithm that is based on prediction.
Doubly Cognitive Architecture Based Cognitive Wireless Sensor Networks
Authors: Kumar Sumit , Singhal Deepti , Murthy Garimella Rama
Published: July 2013

Scarcity of spectrum is increasing not only in cellular communication but also in wireless sensor networks. Adding cognition to the existing wireless sensor network (WSN) infrastructure has helped. As sensor nodes in WSN are limited with constraints like power, efforts are required to increase the lifetime and other performance measures of the network. In this article, the authors propose Doubly Cognitive WSN, which works by progressively allocating the sensing resources only to the most promising areas of the spectrum and is based on pattern analysis and learning. As the load of sensing resource is reduced significantly, this approach saves the energy of the nodes and reduces the sensing time dramatically. The proposed method can be enhanced by periodic pattern analysis to review the strategy of sensing. Finally the ongoing research work and contribution on cognitive wireless sensor networks in Communication Research Centre (IIIT-H) is discussed.
Mobile WiMAX Bandwidth Reservation Thresholds
Authors: Khemiri Sondes , Boussetta Khaled , Achir Nadjib , Pujolle Guy
Published: July 2013

This paper addresses the issue of wireless bandwidth partitioning of a Mobile WiMAX cell. The authors consider a Complete Partitioning strategy, where the wireless bandwidth capacity of a cell is divided into trunks. Each partition is strictly reserved to a particular type of connection. Four IEEE 802.16e 2005 service classes are distinguished: UGS, rtPS, nrtPS, and ErtPS. The authors consider mobility and differentiate new call request from handoffs. In addition, the authors take into consideration the Adaptive Modulation and Coding (AMC) scheme, through the partition of the cell into different areas associated to a particular modulation and coding scheme. The purpose of the paper is to determine, using an analytical model and a heuristic approach, the nearly optimal sizes of the partition sizes dedicated to each type of connection, which is characterized by its service class, type of request and modulation, and coding scheme.
IP Paging for Mobile Hosts in Distributed and Fixed Hierarchical Mobile IP
Authors: Upadhyay Paramesh C. , Tiwari Sudarshan
Published: July 2013

The concept of Paging has been found useful in existing cellular networks for mobile users with low call-to-mobility ratio (CMR). It is necessary for fast mobility users to minimize the signaling burden on the network. Reduced signaling, also, conserves scarce wireless resources and provides power savings at user terminals. However, Mobile IP (MIP), a base protocol for IP mobility, does not support paging concept in its original form. Several paging schemes and micro-mobility protocols, centralized and distributed, have been proposed in literature to alleviate the inherent limitations of Mobile IP. In this paper, the authors propose three paging schemes for Distributed and Fixed Hierarchical Mobile IP (DFHMIP) and develop analytical models for them. Performance evaluations of these schemes have been carried out and results have been compared with DFHMIP without paging and with Dynamic Hierarchical Mobile IP (DHMIP) for low CMR values.
A Framework for External Interference-Aware Distributed Channel Assignment
Authors: Juraschek Felix , Günes Mesut , Blywis Bastian
Published: July 2013

DES-Chan is a framework for experimentally driven research on distributed channel assignment algorithms in wireless mesh networks. DES-Chan eases the development process by providing a set of common services required by distributed channel assignment algorithms. A new challenge for channel assignment algorithms are sources of external interferences. With the increasing number of wireless devices in the unlicensed radio spectrum, co-located devices that share the same radio channel may have a severe impact on the network performance. DES-Chan provides a sensing component to detect such external devices and predict their future activity. As a proof of concept, the authors present a reference implementation of a distributed greedy channel assignment algorithm. The authors evaluate its performance in the DES-Testbed, a multi-transceiver wireless mesh network with 128 nodes at the Freie Universität Berlin.
E-Government Success
Authors: Cordella Antonio
Published: July 2013

E-government is a complex undertaking, which encompasses technological, organizational, and institutional elements. Much research in the field has looked at ICT as a valid solution to make public administration more successful. This chapter offers a richer account of the role played by ICT in transforming public sector organizations, discussing the effects ICTs have in the rationalization of administrative procedures and public sector institutional transformations. The notion of techno-institutional assemblages is introduced to offer a new theoretical ground to frame the notion of success in e-government projects. It is argued here that successful e-government policies are the one that deliver the outcomes, which have led their initiation. Accordingly, the need for new indicators of success is identified.
The Digital Divide vs. the E-Government Divide
Authors: Niehaves Bjoern , Gorbacheva Elena , Plattfaut Ralf
Published: July 2013

E-government is beneficial for both citizens and public administrations. However, there are great differences in citizens’ e-government usage and, thus, there exists a gap between adopters and non-adopters of e-government services. Most related studies explore e-government acceptance on the basis of the entire population, while investigation of onliners rarely takes place. However, being online is a necessary pre-requisite for consuming Internet-based e-government services. Against the background that the number of Internet users is increasing steadily, the authors identify the need to differentiate general Internet adoption (digital divide) effects and e-government-specific divide effects. In the study, they develop a research framework, where the cumulative effect of e-government adoption (among all people) is split into (1) the digital divide effect and (2) the e-government divide effect (among Internet users). The authors derive three corresponding research models and examine the influence of socio-demographic factors: age, gender, income, and education. They test the research framework using comprehensive survey data (n = 1930). Analysis of the results justifies the separation of the e-government divide effect from the cumulative effect of e-government adoption, because the factors influencing e-government usage among the entire population and among onliners are proved to be different. Implications for theory and recommendations for practice are discussed. The findings reveal two important success factors for e-government: citizens’ Internet literacy and e-government services targeted at lesser-educated citizens.
Sustainability of E-Government Success
Authors: Klischewski Ralf , Lessa Lemma
Published: July 2013

The long-term success of e-government initiatives is of paramount importance, especially for developing countries, which face challenges such as limited budget, donor dependence, transfer of technology, short-term involvement of non-local agents, and relatively unstable political and economic environment. Although e-government success and sustainability are both relevant concepts to assess IT-enabled administrative processes in practice, e-government research has not yet elaborated the two concepts in an integrated fashion. Depending on review of the extant literature, this chapter (1) clarifies the concepts of e-government success and sustainability, (2) provides a conceptualization, which unfolds for both concepts the most used sub-concepts and constructs in terms of enablers and evaluation criteria, and (3) proposes an integrated research agenda for studying the interrelation of both concepts in detail.
Empowering Citizens
Authors: Griffiths Mary
Published: July 2013

The federal government of Australia has established an innovative although uneven record in shared governance initiatives in a climate of political stability and broad social inclusion policies. The participatory reform agenda has the potential to increase citizen empowerment, improve government transparency and accountability, and develop the capacities of the administrative arm. Changes to Australian Public Service (APS) practice are now aimed at better support for citizen-centric policy formation and, in some examples, shared governance. Nevertheless, policy consultations remain at the high-risk/high gain end of citizen-government-APS relations. This chapter scopes the concept and contexts of policy co-production both as a technique of engagement and a desirable outcome in shared governance for representative democracies. It assesses policy engagement from the perspective of citizens as agents, not targets. Using a constructivist approach, the chapter assesses the impact of contextual factors, the new participatory reform agenda, and the design features on two consultations conducted in 2011: Clean Energy Legislation, and Digital Culture Public Sphere. Major factors impacting on policy coproduction are found to be context-specific and issue-specific, and outside the direct control of public service agencies. Theoretically, the constructivist approach combines the literature on modes of e-government research, on e-government success factors and participatory media, with evidence of institutional reform agendas and the evidence provided by the case studies. Methodologically, the data is drawn from public domain materials.
Methodology for Risk Assessment and Costs Associated with Risk Occurrence in E-Government Projects
Authors: Vrcek Neven , Peharda Petra , Mundar Dušan
Published: July 2013

The main purpose of this chapter is to emphasize the problem of e-government project risks and to introduce a methodology for risk assessment and calculation of costs associated with risk occurrence in e-government projects based on Bayesian networks. The proposed methodology presents a new approach to the assessment of risks and costs related to e-government project risks. As such, it facilitates the holistic decision making procedure for project managers. The application of Bayesian networks in the context of risks and risk related costs reduces the level of uncertainty in e-government projects and provides a graphical structure of risks and corresponding costs. Finally, the sensitivity analysis has also been integrated into the methodology and its results can have a significant impact on the overall project management quality.
Customer Involvement through Online Communities
Authors: Sasinovskaya Olga , Anderson Helén
Published: July 2013

New online collaborative technologies provide businesses with new opportunities to interact with customers and get them involved more actively in product or service development processes. Different types of online communities provide access to global customers: their ideas and opinions. This chapter presents a review of three types of online communities which might be valuable for businesses, namely marketing activities and new product development. Online communities can assist companies in benefitting from the “wisdom of crowds”, creating customer-oriented image, boosting product portfolio with new ideas and handling negative online publicity. While some types of communities are more effective for solving sharply defined tasks, others can help with creative views due to members’ ability to think “outside of the box”.
Supporting Mathematical Communication through Technology
Authors: Orrill Chandra Hawley , Polly Drew
Published: July 2013

Technology has the potential to support the creation and use of mathematical representations for exploring, reasoning about, and modeling cognitively demanding mathematical tasks. In this chapter, the authors argue that one of the key affordances of these dynamic representations is the synergistic relationship they can play with communication in the mathematics classroom. The authors highlight the ways in which technology-based representations can support mathematical communication in the classroom through a series of vignettes. They conclude with a discussion of the development of teachers’ Technological Pedagogical and Content Knowledge (TPACK) for supporting the implementation of dynamic representations.
A Framework for TPACK Action Research
Authors: Taylor P. Mark
Published: July 2013

In the implementation of the Common Core State Standards, teacher educators have an unprecedented opportunity. Both preservice and inservice teachers are aware that they have much to learn about the effective implementation of the standards. This is especially true in light of the standards inclusion of technology on the list of tools, which students should be selecting and properly using. Action research can be an effective pedagogical tool for teacher educators to employ as we support teachers’ learning about these technology tools for learning mathematics. Four levels of TPACK action research are suggested as a framework for teacher educators to use as they take advantage of this opportunity.
The Incorporation of Geometer’s Sketchpad in a High School Geometry Curriculum
Authors: Ames Lisa , An Heejung , Alon Sandra
Published: July 2013

The Common Core State Mathematics Standards (CCSSM) recommend that technology should be integrated into teaching and learning Mathematics. This chapter addresses how the Geometer’s Sketchpad computer program can support students’ thinking skills and learning outcomes in a high school geometry class, in particular for more effectively addressing the High School Geometry Standards (CCSSM: G.CO.10, G.CO. 11, and G.CO. 12). The findings from the study presented in this chapter indicate that this tool can help high school students increase their learning of geometry in terms of inductive reasoning and conceptual knowledge, but may not help improve students’ motivation to learn geometry.
Do Technologies Support the Implementation of the Common Core State Standards in Mathematics of High School Probability and Statistics?
Authors: Lim Woong , Kim Dong-Gook
Published: July 2013

This chapter reviews the roles of technology in statistics education and introduces technologies available for classroom use. A few concrete examples of how select technologies support the teaching of probability and statistics guided by the Common Core State Standards in Mathematics of high school Probability and Statistics (CCSSM-PS) are presented. The reality of the implementation of the CCSSM poses a rather exciting opportunity for all of us in mathematics education. It presents an opportunity to plan and create mathematics lessons based on good teaching strongly tied with technology. As the efficacy of the CCSSM-PS hinges on how teachers draw upon their content knowledge to facilitate student learning through technology, it is significant to provide professional development programs that help teachers infuse technology with the teaching of probability and statistics.
Two Classroom Portraits Demonstrating the Interplay of Secondary Mathematics Teachers’ TPACK on their Integration of the Mathematical Practices
Authors: Ivy Jessica Taylor , Franz Dana Pomykal
Published: July 2013

This chapter examines the practices and beliefs of two secondary mathematics teachers with similar demographic backgrounds. The influence of their practices and beliefs on teaching and student learning is considered through the lens of the TPACK Development Model and through evidence of student engagement in the Mathematical Practices. Even though they face common barriers to instructional technology integration, both teachers speak to their successes and positive impacts on student learning. Rich descriptions of conversations, classroom observations, and self-report survey data highlight critical contrasts between the practices of the two teachers. These differences represent the unique challenges faced by instructional technology researchers and other educational stakeholders. The purpose of this chapter is to highlight these subtle, yet far-reaching, areas of distinction in which the teachers unknowingly provide different levels of opportunity for teaching and learning in the mathematics classroom.
Supporting the Common Core State Standards in Mathematics through Mathematics Journals
Authors: Martin Christie , Polly Drew
Published: July 2013

The Common Core State Standards in Mathematics and English/Language Arts necessitate that teachers provide opportunities for their students to write about mathematical concepts in ways that extend beyond simply a summary of how students solve mathematical tasks. This study examined how mathematics journals in a fourth grade classroom supported students’ mathematical experiences and reflected their understanding of concepts. Implications for the use of technology to support mathematics journals are also discussed.
Using the iPad to Develop Preservice Teachers’ Understanding of the Common Core State Standards for Mathematical Practice
Authors: Grassetti Mary , Brookby Silvy
Published: July 2013

The Standards for Mathematical Practice as delineated in the Common Core State Standards for Mathematics describe the processes, proficiencies, and habits of mind that students are expected to develop through their engagement with mathematics (Dacey & Polly, 2012). The purpose of this chapter is to discuss, anecdotally, how the iPad, a tablet computer designed by Apple ™, can be used to develop preservice teachers’ understanding and implementation of the Standards for Mathematical Practice, most specifically Mathematical Practice Standard 3: Construct viable arguments and critique the reasoning of others. Under examination are the authors’ experiences using the iPad as an observational tool during student teaching and as a teaching tool in their mathematics methods courses. The chapter concludes with suggestions for additional uses of the iPad to support preservice teachers as they work to develop their understanding of the Standards for Mathematical Practice.
User Segmentation Based on Twitter Data Using Fuzzy Clustering
Authors: Öztaysi Basar , Onar Sezi Çevik
Published: July 2013

Social Networking Sites, which create platform for social interactions and sharing are the mostly used internet websites, thus are very important in today’s world. The vast usage of social networking sites (SNSs) has effected the business world, new business models are proposed, business process are renewed and companies try to create benefit form these sites. Besides the functional usage of SNSs such as marketing and customer relations, companies can create value by analyzing and mining the data on SNSs. In this paper, a new segmentation approach, using Text Mining and Fuzzy Clustering techniques. Text mining is process of extracting knowledge from large amounts of unstructured data source such as content generated by the SNSs users. Fuzzy clustering is an algorithm for cluster analysis in which the allocation of data points to clusters is fuzzy. In the proposed approach, users self description text are used as an input to the Text Mining process, and Fuzzy Clustering is used to extract knowledge from data. Using the proposed approach, companies can segment their customers based on their comments, ideas or any kind of other unstructered data on SNSs.