bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobile Phones, Diasporas and Developing Countries
Authors: Johanson Graeme , Denison Tom
Published: October 2010

It is no coincidence that the mobile phone suits the lifestyle and needs of the mobile migrant worker well. Research into the role of mobile or cell phones by Chinese migrant labourers, migrating within and outside China, show that the phones are a survival device, a means to perpetuate an important sense of belonging to a community in virtual form, and a method of transferring resources back to poor parts of the homeland. Mobiles help to cope in a foreign culture and to find work and ethnic solidarity. Above all, they provide connectedness. This chapter summarises the findings of a survey of 74 Chinese migrants living in Prato, Italy, as an example of Chinese migrants in Europe. It was administered in late 2008. Prato as a province has the largest Chinese migrant population in Italy, numbering about 30,000. The research aimed to understand the usefulness of mobile phones to migrant residents who need to keep in touch with their friends and families, in China and Italy, and their other communication needs, and whether mobiles satisfy their expectations. Participants in this study are well-served by mobiles. The typical participant in the study was a recently-arrived young single male from Zhejiang, China, speaking Wenzhouese, but with proficiency in other languages, experiencing the novelty of using a recently-purchased ‘Nokia’ phone, and who, whilst spending more than 10 Euros a month on the phone for keeping in touch with friends in China, was very aware of mobile running costs. More research is planned to flesh out the findings further.
Empowering Faculty Communities for Fostering and Assessing Student Performance in Virtual Landscapes
Authors: Baumgartner Holly Lynn , Ducat Garrick
Published: October 2010

This chapter presents a case study and a narrative of an experimental course, an undergraduate allied health interdisciplinary seminar, and its corresponding faculty learning community exploring how collaborative learning may be fostered in a virtual world. The objectives of the course included enhancing student technology literacy, engendering reflective practice, and creating a student-focused faculty learning community; additionally, the faculty learning community both inspired and was inspired by students, fueling innovative teaching practices which, as a result, have infused the college curriculum. Receiving mentoring from learning community members, students were responsible for the design, development, and implementation of a virtual solution to a student defined, healthcare-based, needs analysis. The last part of this case study provides explication of the RIME model of student and learning community assessment for use in teaching with a multi-user virtual environment (MUVE) which may, by extension, be applied to other emergent technologies and social media. This instrument assesses student learning outcomes in the areas of retention, immersion, motivation, and engagement.
Collaboration and the Use of Three Dimensional Interface within a Virtual Learning Environment
Authors: Burton Brian G. , Martin Barbara , Thomas Doug
Published: October 2010

This chapter’s goal is to examine the experiences and perceptions of undergraduate students using a 3D Virtual Learning Environment. After creating a 3D didactic constructivist virtual environment, student conversations were observed for collaborative elements. Findings revealed that five forms of collaboration amplified the learning process and indeed occured within the virtual learning environments. Results further suggested that the 3D VLE project, though limited in time and scope, successfully created a community of learners.
Using the 3V Model to Explore Virtuality, Veracity and Values in Liminal Spaces
Authors: Atkinson Simon , Burden Kevin
Published: October 2010

Adaptation and adoption of immature emergent technologies for instruction fails to account for the challenge to, and creation of, new concepts of self, identity and community both in real and virtual spaces. New insight is necessary to develop social policy responses, including those of educational systems and institutions, to the consequences of these new conceptualisations. This chapter presents an original theoretical model which aims to assist in the interpretation of existing theory, exploring the interrelated dimensions of values, virtuality and veracity disturbed by the adaptation of emergent technologies. It invites an exploration of existing theoretical and methodological instruments available within the broader Social Sciences to examine emerging notions of identity. The emergent theoretical model visualizes a set of complex assumptions within the concepts of the “real-virtual” interface created by emergent technologies; the 3V model represents one means of explore internal structure to this liminal space and invites further empirical study.
Exploring the Factors to Determine the Competence of Technology Integration for Teacher Candidates
Authors: Park Hae Seong , Gilbreath Joanne , Lawson Daniel , Williams Helen Easterling
Published: October 2010

The purpose of this study is to examine the factors to determine the competence of technology integration for teacher candidates. This study utilized data from a 2006 quick-response survey entitled ‘Educational Technology in Teacher Education Programs for Initial Licensure.’ Only 1,350 institutions that have teacher education programs for initial licensure were selected. The result of a hierarchical regression revealed that the extent of institutional training programs for technology explain most variation (33%) of the competence of technology integration of teacher candidates. In addition, the more variation of technology programs an institution employs in its program, the more confidence the teacher candidates possess. The result supports findings from previous research as well as supporting some emphasis on professional development design considerations that may be of value to those planning the similar technology trainings.
Bringing the Village to the University Classroom
Authors: Stefl-Mabry Joette , Doane William E.J. , Radlick Michael S.
Published: October 2010

This chapter highlights critical lessons learned during the past six years during the development of a capstone graduate educational technology course, teaching School Library Media (SLMS) pre-service students how to develop learner centered, knowledge centered and assessment centered Web-based learning tools; in short, to enable them to become change agents in their educational communities. A large northeastern University has cultivated educational partnerships that bring together University students with their professional, in-service, PreK-12 counterparts to explore issues of technology in education, pedagogy, theory, curriculum, information literacy, assessment, and evaluation. Unlike traditional courses with prepackaged academic assignments, this course engages school library media specialists with real-world teaching and learning situations that are frequently ill-structured, often chaotic, and collaboratively defined by the learning needs of all participants (PreK-12 through university; in-service and pre-service). The strengths and weaknesses of the course are candidly discussed with recommendations for improvement.
Economic Aspects of Quality of Service for Internet Based IT Services
Authors: Wulf Jochen , Zarnekow Rüdiger
Published: October 2010

In academic research there is a long ongoing and vital discussion on the evolution and design of technologies that enable the management and control of quality of service (QoS) for Internet based IT services. Whereas technological aspects have been extensively discussed, from an industry perspective, there is a strong need for a structured research on economic aspects of QoS. A clear understanding of IT service quality and its dependency on the quality of data transmission is a precondition for an effective design of future service distribution technologies. This work provides an overview on the state of the art in economic QoS research. It discusses economic aspects of QoS on four central economic dimensions: the product dimension, the customer interface dimension, the infrastructure dimension and the financial management dimension. Moreover, this article discusses future QoS prospects and challenges.
Assessing Self-regulation Development through Sharing Feedback in Online Mathematical Problem Solving Discussion
Authors: Kramarski Bracha
Published: October 2010

This study examined the relative efficacies of two different metacognitive teaching methods – problem solving (M_PS) and sharing knowledge (M_SK). Seventy-two Israeli sixth-grade students engaged in online mathematical problem solving and were each supported using one of the two aforementioned methods. M_PS students used a problem-solving and feedback process based on the IMPROVE model (Kramarski & Mevarech, 2003). In contrast, M_SK participants were instructed to reflect and provide feedback on the solution without an explicit model. This study evaluated each method‘s impact on the students’ mathematical online problem solving. It also examined self-regulated learning (SRL) processes by assessing students‘ online feedback using a rubric scheme. Findings indicated that M_PS students outperformed the M_SK students in algebraic knowledge and mathematical reasoning, as well as on various measures of sharing cognitive and metacognitive feedback. The M_SK students outperformed the M_PS students on measures of sharing motivational and social feedback.
Face-to-Face and Web-Forum Interventions Promoting SRL Skills at University
Authors: De Marco Barbara , Businaro Nicoletta , Farina Eleonora , Albanese Ottavia
Published: October 2010

Based on recent findings about Self-Regulated Learning (SRL), we outline three educational interventions aimed at fostering students’ learning competence. Our particular focus is on the interaction between collaborative learning in Technology Enhanced Learning contexts and the development of SRL competencies. Two interventions carried out by our research team involved collaborative activities conducted both face-to-face and in web-based learning environments, aimed at promoting the SRL skills of first year university students. Based on the outcomes of these two projects, a further project for different departments was undertaken. This last intervention was designed to facilitate collaborative reflection on the components and processes of SRL through e-tivities and discussion forums. Our research suggests that collaboration in analyzing and working on the different competencies involved in self-regulated learning is an optimal means of enhancing the self-regulation competencies of university students.
Naive Human T Cells Are Activated and Proliferate in Response to the Heme Oxygenase-1 Inhibitor Tin Mesoporphyrin
Authors: Burt Trevor D. , Seu Lillian , Mold Jeffrey E. , Kappas Attallah , McCune Joseph M.
Published: October 2010

Heme oxygenase-1 (HO-1) and its catabolic by-products have potent anti-inflammatory activity in many models of disease. It is not known, however, if HO-1 also plays a role in the homeostatic control of T cell activation and proliferation. We demonstrate here that the HO-1 inhibitor tin mesoporphyrin (SnMP) induces activation, proliferation, and maturation of naive CD4+ and CD8+ T cells via interactions with CD14+ monocytes in vitro. This response is dependent upon interactions of T cells with MHC class I and II on the surface of CD14+ monocytes. Furthermore, CD4+CD25+FoxP3+ regulatory T cells were able to suppress this proliferation, even though their suppressive activity was itself impaired by SnMP. Given the magnitude of the Ag-independent T cell response induced by SnMP, we speculate that HO-1 plays an important role in dampening nonspecific T cell activation. Based on these findings, we propose a potential role for HO-1 in the control of naive T cell homeostatic proliferation.
LRRK2 Is Involved in the IFN-γ Response and Host Response to Pathogens
Authors: Gardet Agnès , Benita Yair , Li Chun , Sands Bruce E. , Ballester Isabel , Stevens Christine , Korzenik Joshua R. , Rioux John D. , Daly Mark J. , Xavier Ramnik J. , Podolsky Daniel K.
Published: October 2010

LRRK2 was previously identified as a defective gene in Parkinson’s disease, and it is also located in a risk region for Crohn’s disease. In this study, we aim to determine whether LRRK2 could be involved in immune responses. We show that LRRK2 expression is enriched in human immune cells. LRRK2 is an IFN-γ target gene, and its expression increased in intestinal tissues upon Crohn’s disease inflammation. In inflamed intestinal tissues, LRRK2 is detected in the lamina propria macrophages, B-lymphocytes, and CD103-positive dendritic cells. Furthermore, LRRK2 expression enhances NF-κB–dependent transcription, suggesting its role in immune response signaling. Endogenous LRRK2 rapidly translocates near bacterial membranes, and knockdown of LRRK2 interferes with reactive oxygen species production during phagocytosis and bacterial killing. These observations indicate that LRRK2 is an IFN-γ target gene, and it might be involved in signaling pathways relevant to Crohn’s disease pathogenesis.
Genetic Susceptibility to the Delayed Sequelae of Neonatal Respiratory Syncytial Virus Infection Is MHC Dependent
Authors: Tregoning John S. , Yamaguchi Yuko , Wang Belinda , Mihm Dagmar , Harker James A. , Bushell Ellen S. C. , Zheng Ming , Liao Guochun , Peltz Gary , Openshaw Peter J. M.
Published: October 2010

Respiratory syncytial virus (RSV) is a major cause of respiratory morbidity, resulting in hospitalization for bronchiolitis in some infected infants that is associated with wheeze in later life. Genetic factors are known to affect the severity of the sequelae after RSV infection, but the complexity of the temporal and genetic effects makes it difficult to analyze this response in studies in man. Therefore, we developed a murine genetic model to analyze the sequelae occurring after RSV infection in early life. Haplotype-based genetic analysis of interstrain differences in severity identified the MHC as an important genetic determinant. This was confirmed by analysis of responses in congenic mice with different MHC haplotypes. We also found that susceptible strains had high CD8 levels during secondary infection. Analysis of first filial generation, second filial generation, and back-cross progeny produced by intercrossing resistant (H-2k, C3H/HeN) and sensitive (H-2b, BALB/c) strains indicated that susceptibility to sequelae after RSV infection was dominantly inherited but also segregated in a non-MHC–dependent manner. Thus, MHC haplotype and its effect on CD8 cell response is an important determinant of the outcome of neonatal RSV infection.
Identification of an Autophagy Defect in Smokers’ Alveolar Macrophages
Authors: Monick Martha M. , Powers Linda S. , Walters Katherine , Lovan Nina , Zhang Michael , Gerke Alicia , Hansdottir Sif , Hunninghake Gary W.
Published: October 2010

Alveolar macrophages are essential for clearing bacteria from the alveolar surface and preventing microbe-induced infections. It is well documented that smokers have an increased incidence of infections, in particular lung infections. Alveolar macrophages accumulate in smokers’ lungs, but they have a functional immune deficit. In this study, we identify an autophagy defect in smokers’ alveolar macrophages. Smokers’ alveolar macrophages accumulate both autophagosomes and p62, a marker of autophagic flux. The decrease in the process of autophagy leads to impaired protein aggregate clearance, dysfunctional mitochondria, and defective delivery of bacteria to lysosomes. This study identifies the autophagy pathway as a potential target for interventions designed to decrease infection rates in smokers and possibly in individuals with high environmental particulate exposure.
Vitamin D and Multiple Sclerosis: Correlation, Causality, and Controversy
Authors: Smolders Joost
Published: October 2010

The last years, many studies reported associations between correlates of vitamin D exposure and several correlates of multiple sclerosis (MS) disease activity. This review discusses studies on vitamin D status, Expanded Disability Status Scale (EDSS) score, and relapse activity of MS. Furthermore, several considerations for intervention studies on vitamin D supplementation in MS are provided.
Information seeking habits of information and knowledge management students: A University of Johannesburg case study
Authors: Niemand Cornelius J.P.
Published: October 2010

According to Uçak (2007:697), ‘it is important to explore the information behaviours of the students who are being educated in the field of information management since the role they are going to play in establishing connections between information sources and users is crucial’. This study focuses on the identification of the information seeking behaviour of students in the department of Information and Knowledge Management at the University of Johannesburg, South Africa. The research is based on research conducted at the Hacettep University in Ankara, Turkey.
Investigation Protocol for Sensorineural Hearing Loss
Authors: Bhattacharyya Abir K , Thaj Jabin
Published: October 2010

The etiology of sensorineural hearing loss is multifactorial which makes the diagnosis a challenging exercise and often an unsolved mystery. Whilst pure tone audiometry is a mandatory investigation, others such as laboratory and radiology are based on clinical evaluation. This paper puts forward a protocol for the investigation for sensorineural hearing loss.
Carbon monoxide mixing ratios over Oklahoma between 2002 and 2009 retrieved from Atmospheric Emitted Radiance Interferometer spectra
Authors: Yurganov L. , McMillan W. , Wilson C. , Fischer M. , Biraud S. , Sweeney C.
Published: October 2010

Abstract. CO mixing ratios for the lowermost 2-km atmospheric layer were retrieved from downwelling infrared (IR) radiance spectra of the clear sky measured between 2002 and 2009 by a zenith-viewing Atmospheric Emitted Radiance Interferometer (AERI) deployed at the Southern Great Plains (SGP) observatory of the Atmospheric Radiation Measurements (ARM) Program near Lamont, Oklahoma. A version of a published earlier retrieval algorithm was improved and validated. Archived temperature and water vapor profiles retrieved from the same AERI spectra through automated ARM processing were used as input data for the CO retrievals. We found the archived water vapor profiles required additional constraint using SGP Microwave Radiometer retrievals of total precipitable water vapor. A correction for scattered solar light was developed as well. The retrieved CO was validated using simultaneous independently measured CO profiles from an aircraft. These tropospheric CO profiles were measured from the surface to altitudes of 4572 m a.s.l. once or twice a week between March 2006 and December 2008. The aircraft measurements were supplemented with ground-based CO measurements using a non-dispersive infrared gas correlation instrument at the SGP and retrievals from the Atmospheric IR Sounder (AIRS) above 5 km to create full tropospheric CO profiles. Comparison of the profiles convolved with averaging kernels to the AERI CO retrievals found a squared correlation coefficient of 0.57, a standard deviation of ±11.7 ppbv, a bias of -16 ppbv, and a slope of 0.92. Averaged seasonal and diurnal cycles measured by the AERI are compared with those measured continuously in situ at the SGP in the boundary layer. Monthly mean CO values measured by the AERI between 2002 and 2009 are compared with those measured by the AIRS over North America, the Northern Hemisphere mid-latitudes, and over the tropics.
The Hydrological response to climate change of the Lesse and the Vesdre catchments (Wallonia, Belgium)
Authors: Bauwens A. , Sohier C. , Degré A.
Published: October 2010

Abstract. The Meuse is an important rain-fed river in North-Western Europe. Nine millions of people live in its catchment splited over five countries. Projected changes in precipitation and temperature characteristics due to climate change would have significant impact on the Meuse River and its tributaries. In this study, we focus on two tributaries of the Meuse in Belgium the Lesse and the Vesdre catchments. The physically based, distributed model EPICGrid, a model which reflects water-soil-plant continuum, is driven by four sets of meteorological information. Two time slices (2020–2050 and 2070–2100) and two scenarios (wet and dry) were studied. The meteorological scenarios are produced by the CCI-HYDR Perturbation Tool, a tool specially designed for the Belgian climate and taking into account a broad range of models. Water balance, high-flows and low-flows are calculated. It highlights that towards the end of the century, plants may suffer from water shortage and excess. This may lead to a decrease in evapotranspiration and clear changes in water balances. The seasoning contrast in river discharge may be strongly accentuated.
Effect of Pregnancy and Childbirth on Sexuality of Women in Ibadan, Nigeria
Authors: Bello Folasade Adenike , Olayemi Oladapo , Aimakhu Christopher O. , Adekunle Adeyemi O.
Published: October 2010

A study of 375 antenatal attendees to assess women's views and experience in sexual matters during pregnancy and following childbirth. Explanatory variables included the perception women had of sex during pregnancy and after childbirth. Outcome variables were frequency and satisfaction of sexual activity. The commonest reasons for having coitus in pregnancy were marital harmony and facilitation of delivery. Libido rose throughout pregnancy but orgasms were less often experienced. The man-on-top position became less practised. Vaginal intercourse remained the commonest type. Masturbation and anal intercourse increased, while oral sex declined throughout. Marriage (OR 9.0, 95% CI 1.0–79.5) and current cohabitation (OR 13.6, 95% CI 1.6–113.4) were predictors of sex in pregnancy. Dyspareunia and partners' extramarital affairs were deterrent. Vaginal delivery and episiotomy were not significant predictors of postnatal sex. The respondents and their partners seem able to adapt to pregnancy changes and enhance their marital bonds. Anticipatory guidance and informed counselling may encourage this.
Ionic‐Liquid‐Assisted Preparation of Carbon Nanotube‐Supported Uniform Noble Metal Nanoparticles and Their Enhanced Catalytic Performance
Authors: Chu Haibin , Shen Yihong , Lin Liang , Qin Xiaojun , Feng Ge , Lin Ziyin , Wang Jinyong , Liu Haichao , Li Yan
Published: October 2010

An ionic‐liquid‐assisted method is developed for the preparation of noble metal nanoparticles supported on multi‐walled carbon nanotubes (MWCNTs). The addition of a small amount of ionic liquids to the reaction solution leads to a production of well‐crystallized metallic nanoparticles with tunable diameter and narrow size distribution, uniformly dispersed on MWCNTs. The obtained Pt nanoparticles supported on MWCNTs show superior catalytic performance. Both the catalytic activity and stability for the electrochemical oxidation of methanol is remarkably improved. The uniform size of Pt nanoparticles in the composites makes it possible to study the size dependence of the catalytic performance in the selective oxidation of glycerol. The turnover frequency (TOF) has the maximum value at the size of ≈4 nm and the selectivity to glyceraldehyde increases with the particle size.
Nanosheets of Oxides and Hydroxides: Ultimate 2D Charge‐Bearing Functional Crystallites
Authors: Ma Renzhi , Sasaki Takayoshi
Published: October 2010

A wide variety of cation‐exchangeable layered transition metal oxides and their relatively rare counterparts, anion‐exchangeable layered hydroxides, have been exfoliated into individual host layers, i.e., nanosheets. Exfoliation is generally achieved via a high degree of swelling, typically driven either by intercalation of bulky organic ions (quaternary ammonium cations, propylammonium cations, etc.) for the layered oxides or by solvation with organic solvents (formamide, butanol, etc.) for the hydroxides. Ultimate two‐dimensional (2D) anisotropy for the nanosheets, with thickness of around one nanometer versus lateral size ranging from submicrometer to several tens of micrometers, allows them to serve either as an ideal quantum system for fundamental study or as a basic building block for functional assembly. The charge‐bearing inorganic macromolecule‐like nanosheets can be assembled or organized through various solution‐based processing techniques (e.g., flocculation, electrostatic sequential deposition, or the Langmuir–Blodgett method) to produce a range of nanocomposites, multilayer nanofilms, and core–shell nanoarchitectures, which have great potential for electronic, magnetic, optical, photochemical, and catalytic applications.
Primate life histories and dietary adaptations: A comparison of Asian colobines and Macaques
Authors: Borries Carola , Lu Amy , Ossi‐Lupo Kerry , Larney Eileen , Koenig Andreas
Published: October 2010

Primate life histories are strongly influenced by both body and brain mass and are mediated by food availability and perhaps dietary adaptations. It has been suggested that folivorous primates mature and reproduce more slowly than frugivores due to lower basal metabolic rates as well as to greater degrees of arboreality, which can lower mortality and thus fecundity. However, the opposite has also been proposed: faster life histories in folivores due to a diet of abundant, protein‐rich leaves. We compared two primate taxa often found in sympatry: Asian colobines (folivores, 11 species) and Asian macaques (frugivores, 12 species). We first described new data for a little‐known colobine (Phayre's leaf monkeys,Trachypithecus phayrei crepusculus) from Phu Khieo Wildlife Sanctuary, Thailand. We then compared gestation periods, ages at first birth, and interbirth intervals in colobines and macaques. We predicted that heavier species would have slower life histories, provisioned populations would have faster life histories, and folivores would have slower life histories than frugivores. We calculated general regression models using log body mass, nutritional regime, and taxon as predictor variables. Body mass and nutritional regime had the predicted effects for all three traits. We found taxonomic differences only for gestation, which was significantly longer in colobines, supporting the idea of slower fetal growth (lower maternal energy) compared to macaques and/or advanced dental or gut development. Ages at first birth and interbirth intervals were similar between taxa, perhaps due to additional factors (e.g., allomothering, dispersal). Our results emphasize the need for additional data from wild populations and for establishing whether growth data for provisioned animals (folivores in particular) are representative of wild ones. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.
Design, Synthesis, and Molecular‐modeling Study of Aminothienopyridine Analogues of Tacrine for Alzheimer's Disease
Authors: Badran Mohga M. , Hakeem Maha Abdel , Abuel‐Maaty Suzan M. , El‐Malah Afaf , Salam Rania M. Abdel
Published: October 2010

2‐Amino‐3‐cyanothiophenes were successfully condensed with a number of cycloalkanones to afford tacrine analogues in a one‐step reaction mediated with Lewis acid. The newly synthesized compounds have been tested for their ability to inhibit acetylcholine esterase (AChE) activity using tacrine as standard drug. Some of the tested compounds showed moderate inhibitory activity in comparison with tacrine, especially compounds 6a which displayed the highest inhibitory activity. Furthermore, molecular‐modeling studies were performed in order to rationalize the obtained biological results.
Kinetics of MMA and VAc Miniemulsion Polymerizations Using Miglyol and Castor Oil as Hydrophobe and Liquid Core
Authors: Steinmacher F. R. , Bernardy N. , Moretto J. B. , Barcelos E. I. , Araújo P. H. H. , Sayer C.
Published: October 2010

Miniemulsion polymerization reactions of methyl methacrylate (MMA) and vinyl acetate (VAc) for the synthesis of biocompatible polymeric nanoparticles were comparatively studied. 2,2'‐Azo‐bis(isobutyronitrile) was used as initiator, lecithin as surfactant, and Miglyol 812 or castor oil as costabilizers. Despite the propagation coefficient of VAc being ten times higher than that of MMA, the reaction rates of the VAc polymerizations were much lower. In VAc polymerizations a higher amount of low‐molar‐mass polymer was formed which may be attributed to transfer reactions to low‐molar‐mass species. Polymerizations with a high Miglyol 812/VAc ratio were slower and resulted in the formation of a higher amount of low‐molar‐mass polymer compared to polymerizations with a low Miglyol 812/VAc ratio or VAc miniemulsion polymerizations with hexadecane as costabilizer. In reactions with high Miglyol 812/VAc ratios the peak area of the GPC trace corresponding to the polymer was substantially higher than the theoretical polymer content.
Trichostatin A restores Apaf‐1 function in chemoresistant ovarian cancer cells
Authors: Tan Lijun , Kwok Roland P. , Shukla Abhishek , Kshirsagar Malti , Zhao Lili , Opipari Anthony W. , Liu J. Rebecca
Published: October 2010

BACKGROUND:

Chemoresistance is the major factor limiting long‐term treatment success in patients with epithelial ovarian cancers. Most cytotoxic drugs kill cells through apoptosis; therefore, defective execution of apoptotic pathways results in a drug‐resistant phenotype in many tumor types.

METHODS:

A panel of ovarian cancer cell lines was screened for expression and function of the apoptosome components Apaf‐1 and caspase‐9. Expression levels were analyzed by immunohistochemistry and immunoblotting; Apaf‐1 function was determined by assessing the ability of endogenous Apaf‐1 to cleave caspase‐9 in the presence or absence of cytochrome c. The effect of the histone deacetylase inhibitor trichostatin A on Apaf‐1 expression and function was evaluated.

RESULTS:

The authors report here that the resistance of ovarian cancer cells to the proapoptotic effects of chemotherapy is due in part to deficient Apaf‐1 activity. Although Apaf‐1 is expressed in most ovarian cancers, the functional activity is impaired, as Apaf‐1 has a diminished ability to recruit and activate caspase‐9. Treatment of ovarian cancer cells with trichostatin A results in restoration of Apaf‐1 function independent of alterations in Apaf‐1 expression. Furthermore, treating chemoresistant cells with sublethal doses of trichostatin A restores Apaf‐1 function and sensitizes cells to cisplatin‐induced apoptosis.

CONCLUSIONS:

Targeting intrinsic pathway defects for therapeutic intervention may result in sensitizing tumors to standard chemotherapy or triggering apoptosis in the absence of other apoptotic signals. The identification of drugs that can use Apaf‐1 when it is present, yet can overcome its functional inactivation, may be an important clinical advance. Cancer 2011. © 2010 American Cancer Society.
Structural, optical and dielectric studies on K1‐x(NH4)xH2PO4 mixed crystals grown from z‐cut seeds
Authors: De‐Gao Zhong , Bing Teng , Zheng‐He Yu , Xiao‐Hui Ge , Fei You , Hui Xu , Shi‐Ming Zhang , Yue‐Juan Yu , Jiangtao Ma
Published: October 2010

Mixed crystals of K1‐x(NH4)xH2PO4(KADP) were grown from KDP (KH2PO4) dominated mixed solutions with varying molar proportion of ADP (NH4H2PO4) addition. It was found that, as the increase of ADP molar concentration, the growth rate along z‐axis of KADP crystal decreased rapidly. The structure of KADP crystals was investigated by powder XRD and the lattice parameter was calculated. The results showed that the lattice parameter c of KADP crystal increased with the molar concentration of ADP. The optical homogeneity of grown KADP crystals was determined with a differential phase‐shifting interferometry. Frequency dependences of the dielectric constant and dielectric loss of KADP crystals were measured at room temperature (290 K). The dielectric constants of KADP crystals were almost invariant with the increase of frequency. In the region of 102∼104Hz, the values of the dielectric loss reduced with the increase of frequency. The piezo‐resonance coupling effect still exists in KADP crystals at room temperature, but shifted to low frequency band. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of acceptor‐doped Ba‐Ce‐Zr‐O perovskites
Authors: Gdula‐Kasica K. , Mielewczyk‐Gryn A. , Lendze T. , Molin S. , Kusz B. , Gazda M.
Published: October 2010

In this paper the role of the preparation route on the sintering temperature, microstructure and transport properties of BaCe0.8Y0.1Zr0.1O3‐δsolid solution has been studied. In particular, the samples were synthesized by means of the solid‐state and molten salt synthesis method. The sample properties were investigated by means of X‐ray diffraction, scanning electron microscopy and impedance spectroscopy. It was found that a good sintering of the samples could be achieved at 1500 °C for MSS preparation method. The ceramic route, even at higher temperatures, does not lead to better conductivity. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EGR4 displays both a cell‐ and intracellular‐specific localization pattern in the developing murine testis
Authors: Hogarth Cathryn A. , Mitchell Debra , Small Christopher , Griswold Michael
Published: October 2010

Spermatogenesis is an intricately regulated process of cellular differentiation transforming spermatogonial stem cells to spermatozoa. Elimination of the transcription factor EGR4 generates subfertile male mice yet the expression and function of EGR4 in the mammalian testis has yet to be fully investigated. We performed in situ hybridization and immunofluorescence to identifyEgr4transcript and protein localization in the developing murine testis. EGR4 was detected in both germ and somatic cells in the neonatal testis but was specific to germ cells inside the seminiferous epithelium from juvenile development onward. EGR4 also displayed distinct intracellular localization patterns within specific cell populations of the testis. In addition,Egr4‐deficient testis tubules regress from relatively normal to Sertoli cell and undifferentiated spermatogonia only over time. Taken together, these data suggest thatEgr4may regulate spermatogenesis at multiple steps, with roles in the dividing Sertoli cells, peritubular myoid cells, and the meiotic and elongating haploid germ cell populations. Developmental Dynamics 239:3106–3114, 2010. © 2010 Wiley‐Liss, Inc.
SWAP‐70 controls formation of the splenic marginal zone through regulating T1B‐cell differentiation
Authors: Chopin Michaël , Quemeneur Laurence , Ripich Tatsiana , Jessberger Rolf
Published: October 2010

T1 and T2 transitional B cells are precursors for marginal zone B cells (MZB), which surround splenic follicles. MZB are essential for marginal zone formation, are central to the innate immune response, and contribute to adaptive immunity. Differentiation, migration, and homing of MZB and their precursors remain to be fully understood. We show that SWAP‐70, a RhoGTPase‐interacting and F‐actin‐binding protein with functions in cell polarization, migration, and adhesion regulates MZB development and marginal zone formation. The percentage of MZB in spleen of Swap70−/− mice was reduced to about one‐third of that found in WT mice. Swap70−/− T1 cells accumulated in integrin ligandhigh regions of the splenic red pulp and failed to efficiently develop into T2 cells. Adoptive transfer and mixed BM chimera experiments demonstrated this to be a B‐cell intrinsic phenotype. T‐cell‐independent antibody production was not impaired, however, and thus suggests that this process does not require correct homing of MZB precursors. B‐cell adhesion through αLβ2 and α4β1 integrins was hyper‐activated in vitro and on tissue sections, and S1P‐stimulated chemokinesis of MZB was reduced in the absence of SWAP‐70. Thus, SWAP‐70 acts as a regulator of the adhesion process, particularly important for differentiation control of B‐cell precursors and their contribution to splenic tissue formation.
Constant TCR triggering suggests that the TCR expressed on intestinal intraepithelial γδ T cells is functional in vivo
Authors: Malinarich Frano H. , Grabski Elena , Worbs Tim , Chennupati Vijaykumar , Haas Jan D. , Schmitz Susanne , Candia Enzo , Quera Rodrigo , Malissen Bernard , Förster Reinhold , Hermoso Marcela , Prinz Immo
Published: October 2010

Intestinal intraepithelial lymphocytes carrying the γδ TCR (γδ iIEL) are involved in the maintenance of epithelial integrity. γδ iIEL have an activated phenotype, characterized by CD69 expression and increased cell size compared with systemic T lymphocytes. As an additional activation marker, the majority of γδ iIEL express the CD8αα homodimer. However, our knowledge about cognate ligands for most γδ TCR remains fragmentary and recent advances show that γδ T cells including iIEL may be directly activated by cytokines or through NK‐receptors, TLR and other pattern recognition receptors. We therefore asked whether the TCR of γδ iIEL was functional beyond its role during thymic selection. Using TcrdH2BeGFP (Tcrd, T‐cell receptor δ locus; H2B, histone 2B) reporter mice to identify γδ T cells, we measured their intracellular free calcium concentration in response to TCR‐crosslinking. In contrast to systemic γδ T cells, CD8αα+ γδ iIEL showed high basal calcium levels and were refractory to TCR‐dependent calcium‐flux induction; however, they readily produced CC chemokine ligand 4 (CCL4) and IFN‐γ upon TCR triggering in vitro. Notably, in vivo blocking of the γδ TCR with specific mAb led to a decrease of basal calcium levels in CD8αα+ γδ iIEL. This suggests that the γδ TCR of CD8αα+ γδ iIEL is constantly being triggered and therefore functional in vivo.
Targeting SIRP‐α protects from type 2‐driven allergic airway inflammation
Authors: Raymond Marianne , Quang Van Vu , Rubio Manuel , Welzenbach Karl , Sarfati Marika
Published: October 2010

The interplay between innate and adaptive immune responses is essential for the establishment of allergic diseases. CD47 and its receptor, signal regulatory protein α (SIRP‐α), govern innate cell trafficking. We previously reported that administration of CD47+/+ but not CD47−/− SIRP‐α+ BM‐derived DC (BMDC) induced airway inflammation and Th2 responses in otherwise resistant CD47‐deficient mice. We show here that early administration of a CD47‐Fc fusion molecule suppressed the accumulation of SIRP‐α+ DC in mediastinal LN, the development of systemic and local Th2 responses as well as airway inflammation in sensitized and challenged BALB/c mice. Mechanistic studies highlighted that SIRP‐α ligation by CD47‐Fc on BMDC did not impair Ag uptake, Ag presentation and Ag‐specific DO11.10 Tg Th2 priming and effector function in vitro, whereas in vivo administration of CD47‐Fc or CD47‐Fc‐pretreated BMDC inhibited Tg T‐cell proliferation, pinpointing that altered DC trafficking accounts for defective Th priming. We conclude that the CD47/SIRP‐α axis may be harnessed in vivo to suppress airway SIRP‐α+ DC homing to mediastinal LN, Th2 responses and allergic airway inflammation.
Diels–Alder Cycloaddition in Protein Chemistry
Authors: Palomo Jose M.
Published: October 2010

The Diels–Alder reaction is probably, together with aldol condensation, the most commonly used reaction in chemistry. The Diels–Alder approach, which involves a diene and a dienophile not present in any biomolecule, allows a chemoselective reaction without the need of protecting groups. Moreover, water has an extraordinary rate‐accelerating effect on the reaction process. Thus, this chemical approach has been recognized as a promising procedure for protein bioconjugation. In this review some of the most recent advances in the application of the Diels–Alder reaction in selective surface modification, immobilization and biocatalysis will be discussed.
Investigation of the pH gradient formation and cathodic drift in microchip isoelectric focusing with imaged UV detection
Authors: Xu Zhongqi , Okabe Noboru , Arai Akihiro , Hirokawa Takeshi
Published: October 2010

This paper reports the protein analysis by using microchip IEF carried on an automated chip system. We herein focused on two important topics of microchip IEF, the pH gradient and cathodic drift. The computer simulation clarified that the EOF could delay the establishment of pH gradient and move the carrier ampholytes (CAs) to cathode, which probably caused a cathodic drift to happen. After focusing, the peak positions of components in a calibration kit with broad pI were plotted against their pI values to know the actual pH gradient in a microchannel varying time. It was found that the formed pH gradient was stable, not decayed after readily steady state, and migrated to cathode at a rate of 10.0 μm/s that determined by the experimental conditions such as chip material, internal surface coating and field strength. The theoretical pH gradient was parallel with the actual pH gradient, which was demonstrated in two types of microchip with different channel lengths. No compression of pH gradient was observed when 2% w/v hydroxypropyl methyl cellulose was added in sample and electrolytes. The effect of CAs concentration on current and cathodic drift was also explored. With the current automatic chip system, the calculated peak capacity was 23–48, and the minimal pI difference was 0.20–0.42 for the used single channel microchip with the effective length of 40.5 mm. The LOD for the analysis of CA‐I and CA‐II was around 0.32 μg/mL by using normal imaged UV detection, the detected amount is ca. 0.07 ng.
Wenn Vernetzte sich vernetzen
Authors: Wagner Dorothea
Published: October 2010

Ein Erfolgsmodell wird zwanzig: Die Graduiertenkollegs der DFG haben eine neue Kultur des Promovierens in Deutschland begründet. Weitere Impulse könnten sie durch einen intensiveren Austausch untereinander erhalten, wie das Beispiel der Informatik zeigt.
Reliable protein structure refinement using a physical energy function
Authors: Lin Matthew S. , Head‐Gordon Teresa
Published: October 2010

In the past decade, significant progress has been made in protein structure prediction. However, refining models to a level of resolution that is comparable with experimental results and can be used in studies like enzymatic activity still remains a major challenge. We have previously demonstrated that our modular protein–solvent energy function, uniquely involving a potential of mean force description for hydrophobic solvation, works well in protein globular structure prediction and loop modeling. In this work, we couple protein–solvent energy function with our global optimization method stochastic perturbation with soft constraints and use them to refine a collection of template models from submitted predictions to recent Critical Assessment of Techniques for Protein Structure Prediction blind prediction contests. A prediction protocol based on a selection of structures with the lowest energy is able to successfully refine all of the test proteins, and, more importantly, our energy function does not show degradation in prediction when sampling is exhausted. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
Exploratory MCDA for handling deep uncertainties: the case of intelligent speed adaptation implementation
Authors: van der Pas J. W. G. M. , Walker W. E. , Marchau V. A. W. J. , Van Wee G. P. , Agusdinata D. B.
Published: October 2010

Sometimes experts, decisionmakers, and analysts are confronted with policy problems that involve deep uncertainty. Such policy problems occur when (1) the future is not known well enough to predict future changes to the system, (2) there is not enough knowledge regarding the appropriate model to use to estimate the outcomes, and/or (3) there is not enough knowledge regarding the weights stakeholders currently assign to the various criteria or will assign in the future. This paper presents an MCDA approach developed to deal with conditions of deep uncertainty, which is called Exploratory Multi‐Criteria Decision Analysis (EMCDA). EMCDA is based on exploratory modelling, which is a modelling approach that allows policy analysts to explore multiple hypotheses about the future world (using different consequence models, different scenarios, and different weights). An example of a policy problem that can benefit from this methodology is decision making on innovations for improving traffic safety. In order to improve traffic safety, much is expected from Intelligent Speed Adaptation (ISA), an in‐vehicle system that supports the driver in keeping an appropriate speed. However, different MCDA studies on ISA give different results in terms of the estimates of real‐world safety benefits of ISA and the willingness of stakeholders (e.g. the automotive industry) to supply ISA. The application of EMCDA to the implementation of ISA shows that it is possible to perform an MCDA in situations of deep uncertainty. A full analysis taking into account the complete uncertainty space shows that the best policy is to make mandatory an ISA system for young drivers (less than 24 years of age) that restricts them from driving faster than the speed limit. Based on different assumptions, the analysis also shows that ISA policies should not target older drivers. Copyright © 2010 John Wiley & Sons, Ltd.
Abdominal wall malformations in a 15‐year fetopathological study: accuracy of prenatal ultrasonography diagnosis
Authors: Joó József Gábor , Csatlós Éva , Rigó János
Published: October 2010

Objective

The aim of this study was to evaluate the characteristics and diagnostic accuracy of prenatal ultrasonography in the diagnosis of abdominal wall malformations.

Method

The characteristics of 113 pregnancies terminated due to abdominal wall malformations were analyzed.

Results

In cases of gastroschisis and omphalocele, similar female dominance was observed. Among the associated malformations, those affecting the cardiovascular system and the extremities were especially common. Regarding the diagnostic accuracy of prenatal sonography, autopsy confirmed sonographic diagnoses in 91% of omphalocele cases and 79% of gastroschisis.

Conclusion

Prenatal sonographic diagnosis is more accurate in omphaloceles than in gastroschisis. Copyright © 2010 John Wiley & Sons, Ltd.