bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of the Fusarium Mycotoxin Deoxynivalenol on the Health and Performance of Broiler Chickens
Authors: Awad Wageha A. , Hess Michael , Twarużek Magdalena , Grajewski Jan , Kosicki Robert , Böhm Josef , Zentek Jürgen
Published: November 2011

The aim of the present experiment was to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on morphometric indices of jejunum and to follow the passage of deoxynivalenol (DON) through subsequent segments of the digestive tract of broilers. A total of 45 1-d-old broiler chickens (Ross 308 males) were randomly allotted to three dietary treatments (15 birds/treatment): (1) control diet; (2) diet contaminated with 1 mg DON/kg feed; (3) diet contaminated with 5 mg DON/kg feed for five weeks. None of the zootechnical traits (body weight, body weight gain, feed intake, and feed conversion) responded to increased DON levels in the diet. However, DON at both dietary levels (1 mg and 5 mg DON/kg feed) significantly altered the small intestinal morphology. In the jejunum, the villi were significantly (P < 0.01) shorter in both DON treated groups compared with the controls. Furthermore, the dietary inclusion of DON decreased (P < 0.05) the villus surface area in both DON treated groups. The absolute or relative organ weights (liver, heart, proventriculus, gizzard, small intestine, spleen, pancreas, colon, cecum, bursa of Fabricius and thymus) were not altered (P > 0.05) in broilers fed the diet containing DON compared with controls. DON and de-epoxy-DON (DOM-1) were analyzed in serum, bile, liver, feces and digesta from consecutive segments of the digestive tract (gizzard, cecum, and rectum). Concentrations of DON and its metabolite DOM-1 in serum, bile, and liver were lower than the detection limits of the applied liquid chromatography coupled with mass spectrometry (LC-MS/MS) method. Only about 10 to 12% and 6% of the ingested DON was recovered in gizzard and feces, irrespective of the dietary DON-concentration. However, the DON recovery in the cecum as percentage of DON-intake varied between 18 to 22% and was not influenced by dietary DON-concentration. Interestingly, in the present trial, DOM-1 did not appear in the large intestine and in feces. The results indicate that deepoxydation in the present study hardly occurred in the distal segments of the digestive tract, assuming that the complete de-epoxydation occurs in the proximal small intestine where the majority of the parent toxin is absorbed. In conclusion, diets with DON contamination below levels that induce a negative impact on performance could alter small intestinal morphology in broilers. Additionally, the results confirm that the majority of the ingested DON quickly disappears through the gastrointestinal tract.
Protective Effects of Polysaccharides from Soybean Meal Against X-ray Radiation Induced Damage in Mouse Spleen Lymphocytes
Authors: Yao Lei , Wang Zhenyu , Zhao Haitian , Cheng Cuilin , Fu Xiaoyi , Liu Jiaren , Yang Xin
Published: November 2011

The aim of this study was to investigate radioprotective effect of the polysaccharides from soybean meal (SMP) against X-ray radiation-induced damage in mouse spleen lymphocytes. MTT and comet assay were performed to evaluate SMP’s ability to prevent cell death and DNA damage induced by radiation. The results show that, X-ray radiation (30 KV, 10 mA, 8 min (4 Gy)) can significantly increase cell death and DNA fragmentation of mouse spleen lymphocytes. Pretreatment with SMP for 2 h before radiation could increase cell viability, moreover, the SMP can reduce X-ray radiation-induced DNA damage. The percentage of tail DNA and the tail moment of the SMP groups were significantly lower than those of the radiation alone group (p < 0.05). These results suggest SMP may be a good candidate as a radioprotective agent.
The Beneficial Effect of Hydrogen on CO Oxidation over Au Catalysts. A Computational Study
Authors: Hussain Akhtar , Gracia Jose , Niemantsverdriet J. W. , Nieuwenhuys B. E.
Published: November 2011

Density functional theory calculations have been carried out to explore the effect of hydrogen on the oxidation of CO in relation to the preferential oxidation of CO in the presence of excess hydrogen (PROX). A range of gold surfaces have been selected including the (100), stepped (310) surfaces and diatomic rows on the (100) surface. These diatomic rows on Au(100) are very efficient in H-H bond scission. O2 hydrogenation strongly enhances the surface-oxygen interaction and assists in scission of the O–O bond. The activation energy required to make the reaction intermediate hydroperoxy (OOH) from O2 and H is small. However, we postulate its presence on our Au models as the result of diffusion from oxide supports to the gold surfaces. The OOH on Au in turn opens many low energy cost channels to produce H2O and CO2. CO is selectively oxidized in a H2 atmosphere due to the more favorable reaction barriers while the formation of adsorbed hydroperoxy enhances the reaction rate.
Role of Antimicrobial Peptides in Inflammatory Bowel Disease
Authors: Otte Jan-Michel , Vordenbäumen Stefan
Published: November 2011

Inflammatory bowel diseases (IBD) are characterized by a chronic relapsing inflammation of the gastrointestinal mucosa. The etiology and pathogenesis of these disorders such as Crohn’s disease and ulcerative colitis are incompletely understood. Recently, antimicrobial peptides, which are expressed by leukocytes and epithelia, have been implicated in the pathogenesis of IBD. Antimicrobial peptides are pivotal for intestinal defense, shaping the composition of the luminal flora and contributing thereby to the maintenance of intestinal homeostasis. Apart from their antimicrobial activity affecting commensal bacteria, immunomodulatory properties of antimicrobial peptides have been identified, which link innate and adaptive immune response. There is increasing evidence that alterations in mucosal levels of these peptides contribute to IBD pathogenensis.
Role of Fungicides, Application of Nozzle Types, and the Resistance Level of Wheat Varieties in the Control of Fusarium Head Blight and Deoxynivalenol
Authors: Mesterházy Ákos , Tóth Beáta , Varga Monika , Bartók Tibor , Szabó-Hevér Ágnes , Farády László , Lehoczki-Krsjak Szabolcs
Published: November 2011

Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000–2004, 2006–2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control on Fusarium Head Blight (FHB) in wheat and to find ways to improve control of the disease and toxin contamination. In a testing system we have used for 20 years, tebuconazole and tebuconazole + prothioconazole fungicides regularly reduced symptoms by about 80% with a correlating reduction in toxin contamination. Averages across the years normally show a correlation of r = 0.90 or higher. The stability differences (measured by the stability index) between the poorest and the best fungicides are about 10 or more times, differing slightly in mycotoxin accumulation, FHB index (severity) and Fusarium damaged kernels (FDK). The weak fungicides, like carbendazim, were effective only when no epidemic occurred or epidemic severity was at a very low level. Similar fungicide effects were seen on wheat cultivars which varied in FHB resistance. In this study, we found three fold differences in susceptibility to FHB between highly susceptible and moderately resistant cultivars when treated with fungicides. In the moderately resistant cultivars, about 50% of the fungicide treatments lowered the DON level below the regulatory limit. In the most susceptible cultivars, all fungicides failed to reduce mycotoxin levels low enough for grain acceptance, in spite of the fact that disease was significantly reduced. The results correlated well with the results of the large-scale field tests of fungicide application at the time of natural infection. The Turbo FloodJet nozzle reduced FHB incidence and DON contamination when compared to the TeeJet XR nozzle. Overall, the data suggest that significant decreases in FHB incidence and deoxynivalenol contamination in field situations are possible with proper fungicide applications. Additionally, small plot tests can be used to evaluate the quality of the field disease and toxin production.
A novel and facile synthesis of 3-(2-benzofuroyl)- and 3,6-bis(2-benzofuroyl)carbazole derivatives
Authors: Gao Wentao , Zheng Meiru , Li Yang
Published: November 2011

A facile synthesis of hitherto unreported 3-(2-benzofuroyl)carbazoles 3a–k, 3,6-bis(2-benzofuroyl)carbazoles 5a–k, and naphtho[2,1-b]furoylcarbazoles 3l and 5l is described. The synthesis mainly relies on the ultrasound-assisted Rap–Stoermer reaction of 3-chloroacetyl- (1) or 3,6-dichloroacetyl-9-ethyl-9H-carbazole (4) with various salicylaldehydes 2a–k as well as 2-hydroxy-1-naphthaldehyde (2l) in CH3CN with the presence of PEG-400 as catalyst. The procedure offers easy access to benzofuroylcarbazoles in short reaction times and the products are obtained in moderate to good yields.
Non-Hodgkin lymphoma of bone in an HIV-infected patient from Argentina
Authors: Sandkovsky Uriel , Martin Pablo Fernando , Bissio Emiliano
Published: November 2011

Introduction: Human immunodeficiency virus (HIV)-infected patients are at higher risk for development of Non-Hodgkin's lymphoma (NHL). The estimated incidence of NHL in patients with acquired immunodeficiency syndrome (AIDS) is much higher when compared to the general population. Most AIDS-associated NHL are of intermediate- or high-grade B-cell type and involve extranodal sites more frequently. The most common sites are the central nervous system (CNS), gastrointestinal tract, liver, bone marrow and soft tissues. Methodology: We describe a 42-year-old male with risk factors for HIV infection who presented with left leg pain and an osteolytic lesion of the left medial tibia. He was subsequently diagnosed with HIV disease and an open biopsy of his left tibia established the diagnosis of NHL. Results: After starting antiretroviral therapy followed by chemotherapy he achieved remission. Conclusion: Bone lymphomas account for 3% of malignant bone tumors and 4-7% of all extranodal sites. NHL of bone has been infrequently described in patients with AIDS. To our knowledge, this is the first report of NHL of the bone in Argentina.
An Introduction to Reinforcement Learning
Authors: Morales Eduardo F. , Zaragoza Julio H.
Published: November 2011

This chapter provides a concise introduction to Reinforcement Learning (RL) from a machine learning perspective. It provides the required background to understand the chapters related to RL in this book. It makes no assumption on previous knowledge in this research area and includes short descriptions of some of the latest trends, which are normally excluded from other introductions or overviews on RL. The chapter provides more emphasis on the general conceptual framework and ideas of RL rather than on presenting a rigorous mathematical discussion that may require a great deal of effort by the reader. The first section provides a general introduction to the area. The following section describes the most common solution techniques. In the third section, some of the most recent techniques proposed to deal with large search spaces are described. Finally, the last section provides some final remarks and current research challenges in RL.
Hardware Trends and Implications for Programming Models
Authors: Jost Gabriele , Koniges Alice E.
Published: November 2011

The upcoming years bring new challenges in high-performance computing (HPC) technology. Fundamental changes in the building blocks of HPC hardware are forcing corresponding changes in programming models to effectively use these new architectures. The changes in store for HPC will rival the vector to massively parallel transition that scientific and engineering codes and methodologies endured several years ago. We describe some of the upcoming trends in hardware designs, and suggest ways in which software and programming models will advance accordingly.
A Framework for Testing Code in Computational Applications
Authors: Kelly Diane , Hook Daniel , Sanders Rebecca
Published: November 2011

The aim of this chapter is to provide guidance on the challenges and approaches to testing computational applications. Testing in our case is focused on code testing for accuracy as opposed to validating the science models or testing user interfaces. A testing framework is used to present the different challenges. Discussions cover topics such as test oracles and the tolerance problem, testing to address specific goals rather than testing as a process, areas of risk inherent in developing and using computational software, a testing mindset, and the use of technical reviews. Three observational studies are included to illustrate different techniques, problems, and approaches. There is no prescribed way of testing computational code. Instead, an awareness of risks and challenges inherent in computational software can provide the necessary guidance.
Development of an Efficient and Secure Mobile Communication System with New Future Directions
Authors: Yahya Abid , Ghani Farid , Ahmad R. Badlishah , Rahman Mostafijur , Syuhada Aini , Sidek Othman , Salleh M. F. M.
Published: November 2011

This chapter presents performance of a new technique for constructing Quasi-Cyclic Low-Density Parity-Check (QC-LDPC) encrypted codes based on a row division method. The new QC-LDPC encrypted codes are flexible in terms of large girth, multiple code rates, and large block lengths. In the proposed algorithm, the restructuring of the interconnections is developed by splitting the rows into subrows. This row division reduces the load on the processing node and ultimately reduces the hardware complexity. In this method of encrypted code construction, rows are used to form a distance graph. They are then transformed to a parity-check matrix in order to acquire the desired girth. In this work, matrices are divided into small sub-matrices, which result in improved decoding performance and reduce waiting time of the messages to be updated. Matrix sub-division increases the number of sub-matrices to be managed and memory requirement. Moreover, Prototype architecture of the LDPC codes has been implemented by writing Hardware Description Language (VHDL) code and targeted to a Xilinx Spartan-3E XC3S500E FPGA chip.
DQ Based Methods
Authors: Tomasiello Stefania
Published: November 2011

Though relatively unknown, the Differential Quadrature Method (DQM) is a promising numerical technique that produces accurate solutions with less computational effort than other numerical methods such as the Finite Element Method. There are different versions of the former method, so one can refer to a class of methods based on the differential quadrature (DQ) approach. This chapter provides systematic steps to understand DQ based methods: how they work, how to use and develop them, as well as exemplary problems. It is divided into two sections: the first provides fundamentals and theories related to the DQ approach, while the second presents the application of DQ based methods to three significant problems, i.e. free vibrations of a multi-span beam (a typical model for bridge decks and floors), time dependent heat transfer, and vibrations of a rectangular membrane. The main focus is on the application of the method to space-time domains as a whole, an issue not well covered by the current literature.
Science Communication with Dinosaurs
Authors: Manning Phillip L. , Falkingham Peter L.
Published: November 2011

Dinosaurs successfully conjure images of lost worlds and forgotten lives. Our understanding of these iconic, extinct animals now comes from many disciplines, not just the science of palaeontology. In recent years palaeontology has benefited from the application of new and existing techniques from physics, biology, chemistry, engineering, but especially computational science. The application of computers in palaeontology is highlighted in this chapter as a key area of development in studying fossils. The advances in high performance computing (HPC) have greatly aided and abetted multiple disciplines and technologies that are now feeding paleontological research, especially when dealing with large and complex data sets. We also give examples of how such multidisciplinary research can be used to communicate not only specific discoveries in palaeontology, but also the methods and ideas, from interrelated disciplines to wider audiences. Dinosaurs represent a useful vehicle that can help enable wider public engagement, communicating complex science in digestible chunks.
Readiness in Systems Implementation
Authors: Lou Eric , Salleh Hafez
Published: November 2011

Higher education sector is notorious for lagging behind the industrial sector in the application of IT/IS systems and infrastructure. This chapter presents the application of the IT/IS readiness model in a higher education organization. This organisation was established in 1967 and currently has about 2,500 staff and 18,000 students, of which, 3,000 are international students from all over the world. The organization comprises of 14 schools and 13 research institutes and offers programmes various fields, which include virtual reality, magnetic and optics, business, law, genetic algorithms, health-related studies, and building construction. In 1996, Academic Division (AD) identified the need to improve the management of the student database due to the increase of students and programs offered by the organization. AD also identified that the Legacy Student Information System (SIS) was unable to cope with the increasing demand of data administration. This case study presents the overview of issues encountered while assessing the e-readiness of the organisation after most of the systems went live. Post implementation, the system has been able to reduce the redundancies in processes and has been able to provide a more effective support to students and staff. However, still there are several issues and conflicts that need to be resolved, and a radical rethink of the processes supporting the IT system is needed to achieve any further efficiency.
Internet Safety
Authors: Peach Andrea , Bell Susan , Spatariu Alexandru
Published: November 2011

Preschool and young school-aged children use the internet at high rates, and with this access, parents and educators worry about safety issues. Reports of cyberbullying, child predators, inappropriate internet content, and violations of privacy, such as identity theft saturate the media (Dowell, Burgess, & Cavanaugh, 2009). This chapter will explore the roots of cyberbullying, including relational aggression and bullying in early childhood, will examine issues in internet safety that pertain to young children, and will differentiate the issues with young children from those that plague older children. Resources for working with children, parents, and educators will be reviewed, and future safety issues of internet and other mobile technology will be discussed.
A Study of XML Models for Data Mining
Authors: Kutty Sangeetha , Nayak Richi , Tran Tien
Published: November 2011

With the increasing number of XML documents in varied domains, it has become essential to identify ways of finding interesting information from these documents. Data mining techniques can be used to derive this interesting information. However, mining of XML documents is impacted by the data model used in data representation due to the semi-structured nature of these documents. In this chapter, we present an overview of the various models of XML documents representations, how these models are used for mining, and some of the issues and challenges inherent in these models. In addition, this chapter also provides some insights into the future data models of XML documents for effectively capturing its two important features, structure and content, for mining.
Modeling, Querying, and Mining Uncertain XML Data
Authors: Kharlamov Evgeny , Senellart Pierre
Published: November 2011

This chapter deals with data mining in uncertain XML data models, whose uncertainty typically comes from imprecise automatic processes. We first review the literature on modeling uncertain data, starting with well-studied relational models and moving then to their semistructured counterparts. We focus on a specific probabilistic XML model, which allows representing arbitrary finite distributions of XML documents, and has been extended to also allow continuous distributions of data values. We summarize previous work on querying this uncertain data model and show how to apply the corresponding techniques to several data mining tasks, exemplified through use cases on two running examples.
A Framework for Mining and Querying Summarized XML Data through Tree-Based Association Rules
Authors: Mazuran Mirjana , Quintarelli Elisa , Rauseo Angelo , Tanca Letizia
Published: November 2011

In this work we describe the TreeRuler tool, which makes it possible for inexperienced users to access huge XML (or relational) datasets. TreeRuler encompasses two main features: (1) it mines all the frequent association rules from input documents without any a-priori specification of the desired results, and (2) it provides quick, summarized, thus often approximate answers to user’s queries, by using the previously mined knowledge. TreeRuler has been developed in the scenario of the Odyssey EU project dealing with information about crimes, both for the relational and XML data model. In this chapter we mainly focus on the objectives, strategies, and difficulties encountered in the XML context.
XML Mining for Semantic Web
Authors: Berlanga Rafael , Nebot Victoria
Published: November 2011

This chapter describes the convergence of two influential technologies in the last decade, namely data mining (DM) and the Semantic Web (SW). The wide acceptance of new SW formats for describing semantics-aware and semistructured contents have spurred on the massive generation of semantic annotations and large-scale domain ontologies for conceptualizing their concepts. As a result, a huge amount of both knowledge and semantic-annotated data is available in the web. DM methods have been very successful in discovering interesting patterns which are hidden in very large amounts of data. However, DM methods have been largely based on simple and flat data formats which are far from those available in the SW. This chapter reviews and discusses the main DM approaches proposed so far to mine SW data as well as those that have taken into account the SW resources and tools to define semantics-aware methods.
Open Innovation and Organizational Capacities
Authors: Remon Denis
Published: November 2011

Open innovation has gained popularity in recent years. But is the concept new or does it express old realities? The literature review of this case study found that the term “open innovation” is recent and that its development has been facilitated by technological innovations. The case study collected data over a period of eight months from an agrifood SME in Quebec, Canada. The aim was to go beyond the basic model of open innovation and integrate dynamic, absorptive and appropriative capacities into a new working open innovation model. Initial results show that components associated with the basic open innovation model such as intellectual property, joint R&D and co-product development are present as well as certain organizational capacities. The difficulty of applying the concept is due to its interactions rather than its components taken individually. The study concludes that further work is needed to extend the applicability and the foundations of open innovation.
Sources of Innovation and Success in the Food Service Industry
Authors: Juntunen A.T.
Published: November 2011

The purpose of the study in this chapter is to investigate and analyze the sources of innovation and success in food service industry. It also discusses of what kind of network management capabilities were needed in these SME cases. This chapter will demonstrate that the SMEs have a good chance to succeed if they can harness the external knowledge in their start up process. This chapter contributes to the prior strategic management and business networks research by analyzing the selected SME cases in the food service industry.
Dynamic Learning as Entrepreneurial Action in the Context of Open Innovation
Authors: Theodorakopoulos Nicholas , Figueira Catarina , Kakabadse Nada , Kakabadse Andrew
Published: November 2011

Recent scholarly discussion on open innovation put forward the notion that an organisation’s ability to internalise external knowledge and learn from various sources in undertaking new product development is crucial to its competitive performance. Nevertheless, little attention has been paid to how growth-oriented small firms identify and exploit entrepreneurial opportunities (i.e. take entrepreneurial action) related to such development, in an open innovation context, from a social learning perspective. This chapter, based on an instrumental case-firm, demonstrates analytically how learning as entrepreneurial action takes place, drawing on situated learning theory. It is argued that such learning is dynamic in nature and is founded on specific organising principles that foster both inter- and intracommunal learning.
Guanylate Binding Protein 4 Negatively Regulates Virus-Induced Type I IFN and Antiviral Response by Targeting IFN Regulatory Factor 7
Authors: Hu Yu , Wang Jie , Yang Bo , Zheng Nuoyan , Qin Meiling , Ji Yongyong , Lin Guomei , Tian Lin , Wu Xiaodong , Wu Li , Sun Bing
Published: November 2011

IRF7 is known as the master regulator in virus-triggered induction of type I IFNs (IFN-I). In this study, we identify GBP4 virus-induced protein interacting with IRF7 as a negative regulator for IFN-I response. Overexpression of GBP4 inhibits virus-triggered activation of IRF7-dependent signaling, but has no effect on NF-κB signaling, whereas the knockdown of GBP4 has opposite effects. Furthermore, the supernatant from Sendai virus-infected cells in which GBP4 have been silenced inhibits the replication of vesicular stomatitis virus more efficiently. Competitive coimmunoprecipitation experiments indicate that overexpression of GBP4 disrupts the interactions between TRAF6 and IRF7, resulting in impaired TRAF6-mediated IRF7 ubiquitination. Our results suggest that GBP4 is a negative regulator of virus-triggered IFN-I production, and it is identified as a novel protein targeting IRF7 and inhibiting its function.
The Tumor Suppressor ARF Regulates Innate Immune Responses in Mice
Authors: Través Paqui G. , López-Fontal Raquel , Luque Alfonso , Hortelano Sonsoles
Published: November 2011

The innate immune system is the first line of defense against invading organisms, and TLRs are the main sensors of microbial components, initiating signaling pathways that induce the production of proinflammatory cytokines and type I IFNs. An antiviral action for the tumor suppressor alternative reading frame (ARF) has been reported; however, the precise role of ARF in innate immunity is unknown. In this study, we show that ARF plays an important role in regulation of inflammatory responses. In peritoneal macrophages and bone marrow-derived macrophages from ARF-deficient animals, the induction of proinflammatory cytokines and chemokines by TLR ligands was severely impaired. The altered responses of ARF−/− cells to TLR ligands result from aberrant activation of intracellular signaling molecules including MAPKs, IκBα degradation, and NF-κB activation. Additionally, animals lacking ARF were resistant to LPS-induced endotoxic shock. This impaired activation of inflammation in ARF−/− mice was not restricted to TLRs, as it was also shown in response to non-TLR signaling pathways. Thus, ARF−/− mice were also unable to trigger a proper inflammatory response in experimental peritonitis or in 12-O-tetradecanoylphorbol-13-acetate–induced edema. Overexpression of ARF, but not its downstream target p53, rescued the ARF-deficient phenotype, increasing TLR4 levels and restoring inflammatory reaction. An increase in the E2F1 protein levels observed in ARF−/− macrophages at basal condition and after LPS stimulation may be involved in the impaired response in this system, as E2F1 has been described as an inflammatory suppressor. These results indicate that tumor suppressor ARF is a new regulator of inflammatory cell signaling.
Micrometer-Sized Titanium Particles Can Induce Potent Th2-Type Responses through TLR4-Independent Pathways
Authors: Mishra Pankaj K. , Wu Wenhui , Rozo Cristina , Hallab Nadim J. , Benevenia Joseph , Gause William C.
Published: November 2011

Wear debris in joint replacements has been suggested as a cause of associated tissue-damaging inflammation. In this study, we examined whether solid titanium microparticles (mTi) of sufficient size to accumulate as wear debris could stimulate innate or adaptive immunity in vivo. mTi, administered in conjunction with OVA, promoted total and Ag-specific elevations in serum IgE and IgG1. Analysis of transferred transgenic OVA-specific naive T cells further showed that mTi acted as an adjuvant to drive Ag-specific Th2 cell differentiation in vivo. Assessment of the innate response indicated that mTi induced rapid recruitment and differentiation of alternatively activated macrophages in vivo, through IL-4– and TLR4-independent pathways. These studies suggest that solid microparticles alone can act as adjuvants to induce potent innate and adaptive Th2-type immune responses and further suggest that wear debris in joint replacements may have Th2-type inflammatory properties.
Redox Remodeling by Dendritic Cells Protects Antigen-Specific T Cells against Oxidative Stress
Authors: Martner Anna , Aurelius Johan , Rydström Anna , Hellstrand Kristoffer , Thorén Fredrik B.
Published: November 2011

Microorganisms and microbial products induce the release of reactive oxygen species (ROS) from monocytes and other myeloid cells, which may trigger dysfunction and apoptosis of adjacent lymphocytes. Therefore, T cell-mediated immunity is likely to comprise mechanisms of T cell protection against ROS-inflicted toxicity. The present study aimed to clarify the dynamics of reduced sulfhydryl groups (thiols) in human T cells after presentation of viral and bacterial Ags by dendritic cells (DCs) or B cells. DCs, but not B cells, efficiently triggered intra- and extracellular thiol expression in T cells with corresponding Ag specificity. After interaction with DCs, the Ag-specific T cells acquired the capacity to neutralize exogenous oxygen radicals and resisted ROS-induced apoptosis. Our results imply that DCs provide Ag-specific T cells with antioxidative thiols during Ag presentation, which suggests a novel aspect of DC/T cell cross-talk of relevance to the maintenance of specific immunity in inflamed or infected tissue.
Cellulases from Thermophilic Fungi: Recent Insights and Biotechnological Potential
Authors: Li Duo-Chuan , Li An-Na , Papageorgiou Anastassios C.
Published: November 2011

Thermophilic fungal cellulases are promising enzymes in protein engineering efforts aimed at optimizing industrial processes, such as biomass degradation and biofuel production. The cloning and expression in recent years of new cellulase genes from thermophilic fungi have led to a better understanding of cellulose degradation in these species. Moreover, crystal structures of thermophilic fungal cellulases are now available, providing insights into their function and stability. The present paper is focused on recent progress in cloning, expression, regulation, and structure of thermophilic fungal cellulases and the current research efforts to improve their properties for better use in biotechnological applications.
Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Drop Followed by Gas Chromatography-Electron Capture Detector for Determination of Some Pesticides in Water Samples
Authors: Bashiri Juybari Mostafa , Mehdinia Ali , Jabbari Ali , Yamini Yadollah
Published: November 2011

In this study dispersive liquid-liquid microextraction based on solidification of floating organic drop (DLLME-SFO) followed by gas chromatography-electron capture detection (GC-ECD) was developed for determination of some pesticides in the water samples. Some important parameters, such as type and volumes of extraction and disperser solvent and salt effect on the extraction recovery of analytes from aqueous solution were investigated. Under the optimum conditions (extraction solvent: 1-undecanol, 15.0 μL; disperser solvent: acetone, 1.0 mL, and without salt addition), the preconcentration factors were obtained ranged from 802 to 915 for analytes. The linear ranges were from 0.05 to 100 μg L−1, and detection limits ranged from 0.05 to 0.008 μg L−1. The relative standard deviations (RSDs%, ) were between 3.2% and 6.7%. The proposed method was successfully applied to the determination of target analytes in the tap, sea, and river water samples, and satisfactory recoveries were obtained.
Incorporation of 3-Aminobenzanthrone into 2′-Deoxyoligonucleotides and Its Impact on Duplex Stability
Authors: Lukin Mark , Zaliznyak Tanya , Johnson Francis , de los Santos Carlos R.
Published: November 2011

3-Nitrobenzanthrone (3NBA), an environmental pollutant and potent mutagen, causes DNA damage via the reaction of its metabolically activated form with the exocyclic amino groups of purines and the C-8 position of guanine. The present work describes a synthetic approach to the preparation of oligomeric 2′-deoxyribonucleotides containing a 2-(2′-deoxyguanosin-N2-yl)-3-aminobenzanthrone moiety, one of the major DNA adducts found in tissues of living organisms exposed to 3NBA. The NMR spectra indicate that the damaged oligodeoxyribonucleotide is capable of forming a regular double helical structure with the polyaromatic moiety assuming a single conformation at room temperature; the spectra suggest that the 3ABA moiety resides in the duplex minor groove pointing toward the 5′-end of the modified strand. Thermodynamic studies show that the dG(N2)-3ABA lesion has a stabilizing effect on the damaged duplex, a fact that correlates well with the long persistence of this damage in living organisms.
The ideal of relations for the ring of invariants of $n$ points on the line
Authors: Howard Benjamin , Millson John J. , Snowden Andrew , Vakil Ravi
Published: November 2011

The ring of projective invariants of

n

ordered points on the projective line is one of the most basic and earliest studied examples in Geometric Invariant Theory. It is a remarkable fact and the point of this paper that, unlike its close relative the ring of invariants of n unordered points, this ring can be completely and simply described. In 1894 Kempe found generators for this ring, thereby proving the First Main Theorem for it (in the terminology introduced by Weyl). In this paper we compute the relations among Kempe’s invariants, thereby proving the Second Main Theorem (again in the terminology of Weyl), and completing the description of the ring 115 years later. This paper introduces a number of new tools to the problem, and uses the graphical algebra formalism to intermediate between representation-theoretic arguments (for symmetric and Lie groups), and the symmetry-breaking of the Speyer–Sturmfels degeneration.
Opening gaps in the spectrum of strictly ergodic Schrödinger operators
Authors: Avila Artur , Bochi Jairo , Damanik David
Published: November 2011

We consider Schr¨odinger operators with dynamically defined potentials arising from continuous sampling along orbits of strictly ergodic transformations. The Gap Labeling Theorem states that the possible gaps in the spectrum can be canonically labelled by an at most countable set defined purely in terms of the dynamics. Which labels actually appear depends on the choice of the sampling function; the missing labels are said to correspond to collapsed gaps. Here we show that for any collapsed gap, the sampling function may be continuously deformed so that the gap immediately opens. As a corollary, we conclude that for generic sampling functions, all gaps are open. The proof is based on the analysis of continuous SL(2,

\mathbb R

) cocycles, for which we obtain dynamical results of independent interest.
Expansion in $SL_d(\mathcal{O}_K/I)$, $I$ square-free
Authors: Varjú Péter P.
Published: November 2011

Let

S

be a fixed symmetric finite subset of

SL_d(\mathcal{O}_K)

that generates a Zariski dense subgroup of

SL_d(\mathcal{O}_K)

when we consider it as an algebraic group over

\mathbb Q

by restriction of scalars. We prove that the Cayley graphs of

SL_d(\mathcal{O}_K/I)

with respect to the projections of

S

is an expander family if

I

ranges over square-free ideals of

\mathcal{O}_K

if

d=2

and

K

is an arbitrary numberfield, or if

d=3

and

K=\mathbb Q

.
A note on $n$-gerbes and transgressions
Authors: Spera Mauro
Published: November 2011

In this note we provide an explicit interpretation of a class of

(q-1)

-gerbes with multi-layered connections in terms of transgression of a fibrewise closed

q

-form on a fibration to a closed

(q+1)

-form on the base manifold, with the basic example of the Euler class of an oriented vector bundle in mind (

q \geq 0

). Picken's and Ferreira–Gothen’s

n

-gerbopoles are discussed from this point of view. Furthermore, string structures (à la Cocquereaux–Pilch and à la Spera–Wurzbacher) are briefly addressed and recast within the proposed framework.
Two results on the rank partition of a matroid
Authors: Berget Andrew
Published: November 2011

The rank partition of a matroid M is the maximum dominance ordered partition

\rho

such that the ground set of M can be partitioned into independent sets of sizes

\rho_1

,

\rho_2

, …. We prove two structural results on this partition, both motivated by representation theory of the general linear group. The first result characterizes the rank partition in terms of standard Young tableaux with a certain matroidal property. The second result says that the rank partition interacts nicely with certain polytopal decompositions of the matroid polytope of M. We also describe the representation theoretical motivation of these results.
Assessing the Walkability of the Workplace: A New Audit Tool
Authors: Dannenberg Andrew L. , Cramer Todd W. , Gibson Christopher J.
Published: November 2011

Purpose.

Walking can be incorporated into most people's daily routines if the process is made convenient by a well-designed built environment. Walkability rarely is assessed in the workplace, where adults spend much of their time.

Methods.

From existing tools, we developed an instrument to audit walkability at a single government agency's facilities, which were located in multiple states. We used a five-point scale to evaluate nine elements of walkability: pedestrian facilities, pedestrian-vehicle conflicts, crosswalks, route maintenance, walkway width, roadway buffer, universal accessibility, aesthetics, and shade. Weighted scores ranged from 20 to 39 (poor), to 40 to 69 (fair), to 70 to 100 (good).

Results.

Of 79 walking route segments surveyed on 10 agency campuses, 34% were rated poor, 32% fair, and 34% good. Repeat assessment of 20 walking route segments by three independent observers yielded similar scores.

Conclusion.

Facility planners may find this walkability instrument useful in identifying and eliminating barriers to convenient walking opportunities in workplaces such as office parks and university campuses.
Empowering Youth for Tobacco Control
Authors: Dunn Caroline L. , Pirie Phyllis L.
Published: November 2011

Purpose.

To investigate common youth group activities and how they relate to young people's attitudes of empowerment around tobacco control.

Design.

A mailed survey was administered to 940 Minnesota youth involved in locally organized tobacco prevention groups. By multivariate linear regression, participation in eight tobacco-related activities and selected personal characteristics were examined in relation to youths' perceived influence on youth smoking.

Results.

Two activities–developing materials with antismoking messages and taking action to change school smoking policies—were associated with significantly higher perceived influence scores for the youth involved (p < .05). Youth in groups who had worked to raise awareness of how the tobacco industry targets teens also had significantly higher influence scores (p < .001). Associated personal factors included high involvement in extracurricular activities (p < .001), having never experimented with smoking (p < .01), leadership experience (p < .001), and being white (p < .01).

Discussion.

Some youth group activities and strategies may be particularly effective at instilling attitudes of empowerment for tobacco control among youth.
Suitability of Commuting by Bicycle to Arizona Elementary Schools
Authors: Sisson Susan B. , Lee Sarah M. , Burns Elizabeth K. , Tudor-Locke Catrine
Published: November 2011

Purpose.

To determine the biking suitability (i.e., bikeability) of and prevalence of biking in 14 elementary schools representing two extremes of bused students (2.4% vs. 53.6%).

Methods.

Street segments (within 0.25-mile radius of school) were scored for bikeability. Bikes in racks per school student population established biking prevalence. Mann-Whitney U-test compared bikeability and prevalence of biking between groups.

Results.

A total of 12.5 ±2.2 streets per school were assessed. Thirteen schools scored very good (<3.0) and one scored fair (4.0–4.9). Median bikeability score was 0.69 for the low-busing schools and 0.53 for the high-busing schools (nonsignificant). Median biking prevalence was 3.1% in the low-busing schools and 1.3% in the high-busing schools (p < .05).

Conclusion.

Streets surrounding schools were adequate for biking. Biking prevalence was significantly higher in low-busing schools but was relatively low in both low- and high-busing schools. Other factors, including intraindividual, social, school, and community, likely contribute to choice of biking to school.
Couples' Reports of Support for Smoking Cessation Predicting Women's Late Pregnancy Cessation
Authors: Pollak Kathryn I. , Baucom Donald H. , Palmer Carleton A. , Peterson Bercedis L. , Østbye Truls , Stanton Susan
Published: November 2011

Purpose.

Although social support has been linked to smoking cessation, no studies have examined whether social support predicts women's late pregnancy cessation. Further, few have included reports from both support recipients and providers.

Design.

Longitudinal.

Subjects.

Pregnant couples (n = 394) reported support for cessation in early (13–20 weeks) and late (28 weeks) pregnancy.

Measures.

Different measures of couples' support were tested for predicting women's late pregnancy cessation. Measures of couples' support that were calculated included: summative (added women's and male partners' support scores, possible range 2–10), difference (subtracted the lower score from the higher, possible range 0–4), strong link (used higher positive or lower negative score, possible range 1–5), weak link (lower positive or higher negative score, possible range 1–5), and female and male reports alone (possible ranges 1–5). Covariate-adjusted odds ratios for the association of these various measures of couples' support with women's late pregnancy cessation were calculated.

Results.

Of the 12 scores (6 positive, 6 negative), only summative (p = .03) and weak link (p = .05) for positive support predicted women's quitting.

Conclusion.

Neither women's nor male partners' reports alone predicted women's cessation; only when both scores were considered, either by adding the scores or by taking the lower score, was the positive support score predictive. Future studies of social support should include support recipients' and providers' perspectives.
Impediment Profiling for Smoking Cessation: Application in the Worksite
Authors: O'Connell Meghan , Comerford Beth Patton , Wall Hilary K. , Yanchou-Njike Valentine , Faridi Zubaida , Katz David L.
Published: November 2011

Purpose.

To replicate results of a pilot smoking cessation study and demonstrate applicability to a worksite setting.

Methods.

Smokers employed by a community hospital participated in an onsite smoking cessation program. Participants used an “impediment profiling” instrument to rate personal barriers to cessation and were assigned to between one and seven interventions. Cessation was defined as carbon monoxide concentration in expired air of ≤ 10 ppm.

Results.

Fifty-one employees participated. Subjects lost to follow-up were assumed to be smoking, resulting in a 39.2% 1-year quit rate; 47.5% of program completers (n = 40) were smoke-free at 1 year. Self-reported quit rate at 2.5 years was 25.5% (17 lost to attrition assumed to be smoking) with 38.2% of program completers smoke-free.

Discussion.

This study suggests that impediment profiling holds promise for smoking cessation and demonstrates feasibility in a worksite setting. Further evaluation of this intervention in the context of randomized controlled trials is warranted.
Prenatal Smoking Cessation among Black and White Women in Eastern North Carolina
Authors: Orr Suezanne T. , Newton Edward R. , Weismiller David G.
Published: November 2011

Purpose.

Limited information is available about Black: White disparities in prenatal smoking cessation, and the results of prior research are inconsistent. We analyzed smoking cessation and factors associated with cessation (attitudes, environment, and nicotine addiction) in a sample of pregnant Black and White women.

Methods.

Women were interviewed at the first prenatal visit at two hospital-based clinics.

Results.

Among former and current smokers, there were no significant differences in the percentage of former smokers between Black (46.8%) and White (43.3%) pregnant women, or in the percentage of “spontaneous quitters” (i.e., those who quit after learning that they were pregnant) for Blacks (36%) and Whites (28%). Both Black and White spontaneous quitters had evidence of occasional relapses to smoking. For Black and White women, smoking more than a pack a day prior to pregnancy was associated with smoking during pregnancy.

Discussion.

Among current and former smokers, spontaneous cessation was about the same for Black and White women, and about two thirds of women who were smokers when they learned of the pregnancy continued to smoke during pregnancy. Nicotine addiction contributed to continued smoking.
Diel changes in bulk and single‐cell bacterial heterotrophic activity in winter surface waters of the northwestern Mediterranean Sea
Authors: Ruiz-González Clara , Lefort Thomas , Massana Ramon , Simó Rafel , Gasol Josep M.
Published: November 2011

Two diel cycle studies were conducted to determine the effect of day—night light changes on winter bacterial activity in the coastal Mediterranean (Blanes Bay Microbial Observatory). Bacterial abundances, bacterial heterotrophic activity, and flagellate grazing counts were determined at 4‐h intervals during two 3‐d periods separated by 2 d. Twice a day, the single‐cell activity of major bacterial groups was further analyzed by applying microautoradiography combined with catalyzed reporter deposition—fluorescence in situ hybridization. During the first cycle, all the measured parameters (including the number of active cells in most groups) varied synchronously, with higher values at night and lower during the day. An episode of strong winds between the two studied periods disrupted this periodicity at the onset of the second cycle. The bulk incorporation of 3H‐leucine recovered the diel pattern after 2 d, mostly driven by the activity of Gammaproteobacteria. Among the possibilities considered, the observed nighttime increases in the grazing activity of heterotrophic nanoflagellates appeared to partially drive the activity of all bacterial taxa through potential periodic release of dissolved organic matter.