bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Gold Nanoparticles Coated with pH-Responsive Polymers and Evaluation of the Cellular Uptake
Authors: Ito Takeo , Kusaka Eriko , Isobe Yu , Nishimoto Sei-ichi 
Published: November 2012

ABSTRACTGold nanorods (AuNRs) show surface plasmon absorption bands in the near-infrared region. This characteristic property has stimulated utilization of gold nanorods as novel nanoprobes for noninvasive bioimaging, such as photoacoustic tomography. Herein, we discuss the synthesis of a series of gold nanorods coated with pH-responsive polymers to investigate the effect of the surface structure and zeta potential of nanoparticles on cellular uptake via a surface charge-mediated endocytic pathway. The surface of the gold nanorods was modified with polyethylene glycol (PEG@AuNR) and tertiary amine derivatives, specifically, diethylaminoethyl ester (1@AuNRs), its amide analog (2@AuNRs), and dimethylaminoethyl ester (3@AuNRs). It was found that the pH-sensitivity of1@AuNRs was relatively high and the surface was positively charged at lower pH. In contrast, the tertiary amino group of1@AuNRs was deprotonated to form an electrostatically neutral surface at higher pH. The pH-responsive gold nanorods were incubated with A549 cells (human lung cancer cells) to quantify the amount of cellular uptake using inductively coupled plasma mass spectrometry. The results indicate that1@AuNRs can be taken up efficiently in the cells, and thereafter, slowly flow out of the cells. Interestingly, only small amounts of the amide analog (2@AuNRs) were taken into the cells, suggesting minor structural changes may affect the interaction between the cell surface and AuNRs. This study highlights a potential application of pH-sensitive nanorods as a probe for bioimaging the acidic environment of tumors.
Demonstration of biocompatibility of single walled carbon nanotubes with blood leukocytes
Authors: Medepalli Krishnakiran , Alphenaar Bruce , Raj Ashok , Sethu Palaniappan 
Published: November 2012

ABSTRACTSingle walled carbon nanotubes (SWNTs) possess unique structural and functional properties. Their ability to be functionalized with different biomolecules makes them excellent candidates for biomedical applications like targeted drug delivery and cancer diagnostics. However, prior to use in therapeutic applications, biocompatibility of SWNTs needs to be thoroughly investigated. Blood is a living tissue and contains cells which can potentially interact with SWNTs during the drug delivery process. The interaction of leukocytes in blood with the SWNTs can provide information regarding the immune response of the host to the nanotubes. Here, we evaluated the acute immune response of leukocytes in blood to SWNTs via (a) direct interaction, due to the presence of SWNTs in circulation and (b) indirect interaction, due to the presentation of SWNTs to leukocytes via antigen presenting cells. These SWNTs were non-covalently functionalized with single stranded DNA (ss-DNA) that acts as a surfactant for suspending SWNTs in aqueous solutions and also serves as a backbone for attaching and transporting different biomolecules. Isolation of cells from blood was done using density gradient centrifugation. Early activation markers were used to study the activation of different leukocyte subpopulations and any activation results in changes of these markers. Flow cytometry was done to analyze the different subpopulations. Results of our study demonstrated that ss-DNA functionalized SWNTs do not elicit an immune response from leukocytes in blood via direct or indirect interaction. This intensive study demonstrates the biocompatibility of single walled carbon nanotubes and paves the way for their safe use in drug delivery and cancer therapeutics without cytotoxicity.
A Multiscale Approach to Assess the Effect of Multilevel Structuring on the Properties of Hierarchical Lattice Materials
Authors: Vigliotti Andrea , Pasini Damiano 
Published: November 2012

ABSTRACTNatural materials have often a defined multilevel hierarchy which governs their macroscopic mechanical properties. Cork, sponge and bone are only a few examples. These materials are generally heterogeneous and can exhibit a cellular pattern, i.e. a partition of a solid with voids, at multiple levels of the structural hierarchy. It is well known that the arrangement of the voids plays a major role in the overall performance of the material. Furthermore, it has been demonstrated that the nesting of cellular patterns at different levels confers remarkable mechanical properties to the structure.This paper presents a multiscale approach to the analysis of a hierarchical structure which exhibits nested levels of lattice, i.e. regular periodic patterns of voids occur at different length scales. A number of three-dimensional topologies as well as the effect of lattice geometry parameters have been investigated. The results of the analysis are plotted onto material property charts. The visualization of the properties helps gain insight into the contribution that each hierarchical layer imparts to the overall properties of a component hierarchically structured with lattice materials.
THE THIRD GENERATION OF THE DIRAC CONE AS A PROOF OF STACKED 2D ELECTRON SYSTEMS IN IRON PNICTIDES
Authors: Kusakabe Koichi 
Published: November 2012

ABSTRACTThe nodal SDW order parameter on a cylindrical Fermi surface is thought to create the Dirac cone in the metallic ground state of iron pnictides and iron chalcogenides. Confirming appearance of the Dirac cone in DFT-GGA solutions of FeSe, we discuss origin of the bulk SDW order parameter in the stacked two-dimensional electronic system. In a layered system with vanishingly small inter-layer single-particle hopping processes, the exchange channels derived for the inter-plane magnetic interaction is the super-exchange counterpart of the two-particle Coulomb scattering for the pair-hopping channel in the layered superconductivity. The fluctuation reference method of the multi-reference density functional theory concludes existence of the inter-layer super-exchange interaction by the Coulomb off-diagonal elements among orbitals in the semi-metallic band structure. Thus a proof of 2D nature of the third generation Dirac cone in iron pnictides induced by SDW also promotes understanding of the high-temperature superconductivity.
Structure and Mechanical Performance of Teleost Fish Scales
Authors: Zhu Deju , Szewciw Lawrence , Vernerey Franck , Barthelat Francois 
Published: November 2012

ABSTRACTIn this work, we have studied the structure and mechanics of fish scales from striped bass (Morone saxatilis). This scale is about 200-300 μm thick and consists of a hard outer bony layer supported by a softer cross-ply of collagen fibrils. Puncture tests with a sharp needle indicated that a single fish scale provides a high resistance to penetration which is superior to polystyrene and polycarbonate, two engineering polymers that are typically used for light transparent packaging or protective equipment. Under puncture, the scale undergoes a sequence of two distinct failure events: First, the outer bony layer cracks following a well defined cross-like pattern which generates four “flaps” of bony material. The deflection of the flaps by the needle is resisted by the collagen layer, which in biaxial tension acts as a retaining membrane. Remarkably this second stage of the penetration process is highly stable, so that an additional 50% puncture force is required to eventually penetrate the collagen layer. The combination of a hard layer that can fail in a controlled fashion with a soft and extensible backing layer is the key to the resistance to penetration of individual scales.
Standards & Regulations in the United States: What Went Wrong?
Authors: Ewing Rodney C. 
Published: November 2012

ABSTRACTIn this paper, I discuss the basis for the following recommendations for the development of standards and regulations for the long-term disposal of spent nuclear fuel and high-level nuclear waste in a geologic repository:•The standard and supporting regulations for the licensing of a geologic repository should begeneric- applicable to all potential sites. These standards and regulations should be finalized prior to the site-selection process.•Site-selection should be based on a set of common-sense criteria [1]. If during site characterization process it is discovered that the site does not meet the technical criteria, the site should be abandoned. These criteria should not only consider the characteristics of the site, but should also include careful consideration of the degree to which a site can be analyzed. Unnecessary complexity may jeopardize the confidence in the analysis of a suitable site.•The standard must acknowledge and adapt its structure and standard-of-proof to the fact that there are two time-scales of interest: thehuman time-scalethat extends to some thousands of years and thegeologic time-scalethat extends to many hundreds of thousands of years. Reasonable and robust containment at both time scales is possible, but the type of analysis and standard-of-proof will be different for each.•Because there are two time-scales and because the types of “proof” for each are very different, the total system analysis of performance, reduced to a single numerical estimate of risk at some very distant time, should be abandoned. The standard should not require scientists and engineers to complete an analysis that is at its best opaque and at its worst not believable.
Transparency and Public Participation in Radioactive Waste Management
Authors: Zakrzewska-Trznadel Grazyna , Andersson Kjell 
Published: November 2012

ABSTRACTSelection of appropriate sites for disposal of radioactive waste, especially high level waste and spent nuclear fuel, is a controversial task, not only from technological but also from societal point of view. A key part of the nuclear facility development is public consultation before the siting, construction and operation of the new repository. All decisions on these issues should be made in clear and transparent manner. The involvement of the local community from the very beginning of planning process may avoid faults and misunderstandings resulting in social objections and organized protests in future. To enhance the public participation in decision-making process several approaches of communication with the society were elaborated in the countries with well-developed nuclear power industry. Special models for communicating with stakeholders to build the acceptance and confidence concerning the radioactive waste management may be also helpful for Poland – the country entering the nuclear energy pathway. An effort to adapt the RISCOM Process developed in Sweden and also implemented in Czech Republic, to Polish conditions will be made in the scope of the EC-FP 7 IPPA project.
Corrosion behavior of spent nuclear fuel in high pH solutions – Effect of hydrogen
Authors: Loida A. , Gens R. , Bube C. , Lemmens K. , Cachoir C. , Mennecart T. , Kienzler B. 
Published: November 2012

ABSTRACTIn accordance with the Belgian “supercontainer design”, spent nuclear fuel (SNF) will be encapsulated in carbon steel canisters, surrounded by a concrete overpack for disposal in poorly-indurated clay. After re-saturation of the barriers by porewater, interactions with the concrete will result in solutions rich in NaOH, KOH and Ca(OH)2. Corrosion studies of SNF in ECW-type solution (Evolved Cement Water) and YCWCa-type solution (Young Cement Water with Ca) were performed under externally applied H2 overpressures over 426 days. Directly after H2 application, Tc concentrations decreased from >10-8 M to concentrations below detection limit. Based on the fractional release of selected fission products, low matrix dissolution rates of ~10-8/day were found in both experiments. U concentrations decreased finally to 1.5•10-9 M (YCWCa) and to 2.1•10-10 M (ECW), respectively. Am, Np and Pu concentrations were found throughout the experiments below their detection limits indicating an effective retention process.
Effects of different bleaching methods on shear bond strengths of orthodontic brackets
Authors: Gungor Ahmet Yalcin , Ozcan Erhan , Alkis Huseyin , Turkkahraman Hakan 
Published: December 2012

ABSTRACT

Objective:
To evaluate the effects of different bleaching methods on the shear bond strength (SBS) of orthodontic brackets.

Materials and Methods:
Forty-five freshly extracted premolars were randomly divided into three groups (n  =  15 per group). In group I, bleaching was performed with the office bleaching method. In group II, bleaching was performed with the home bleaching method. Group III served as the control. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets were tested with a Universal testing machine.

Results:
Analysis of variance indicated a significant difference between groups (P &lt; .001). The highest values for SBS were measured in group III (20.99 ± 2.32 MPa). The SBS was significantly lower in groups I and II than in group III (P &lt; .001). The lowest values for SBS were measured in group II (6.42 ± 0.81 MPa). SBS was significantly higher in group I than in group II (P &lt; .001).

Conclusions:
Both of the bleaching methods significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with the home bleaching method affected SBS more adversely than did bleaching with the office bleaching method.
Land Tenure Change and Sustainable Management of Alpine Grasslands on the Tibetan Plateau: A Case from Hongyuan County, Sichuan Province, China
Authors: Li Jin 
Published: December 2012

Abstract
The Chinese government has introduced a grassland Household-Contracted Responsibility System (HCRS) to contract out pasture use rights to households. This aims to strengthen exclusive use and to achieve sustainable management through privatization of user rights. The author undertook a case-study in the alpine grasslands of Hongyuan County on the Qinghai-Tibetan Plateau to document the initiation and impact of these changes. Herders in this location have traditionally utilized complex user-right arrangements to manage their grassland common pool resources. Analysis of changes brought about through the HCRS process indicate that sustainable management of alpine grasslands aims at the establishment and maintenance of cooperative management institutions and mechanisms that can (a) negotiate between the Tibetan communities and the state, and (b) recognize and support the existing, traditional, management capacity of these communities.
Swinging between Nomadism and Sedentarism: A Case Study of Social and Environmental Change in the Nomadic Society of the Altay Steppes, Xinjiang
Authors: Tsui Yenhu 
Published: December 2012

Abstract
The Altay Steppes are part of the vast Eurasian grasslands where nomadic peoples have lived for thousands of years. Mobile pastoral production is still practised in these steppes. In recent years, however, dramatic changes have occurred in the rangeland society and production system. These have mainly resulted from modernization policies at both state and Xinjiang Uyghur Autonomous Region level. Mobile pastoral production is shrinking and herders are switching between subsistence farming and other livelihood alternatives, at times managing to follow specialized livestock production strategies involving seasonal livestock migrations along transhumance routes. This paper uses original ethnographic data in the form of two case studies to describe this flux in a southern Altay Steppe community. Its Kazakh and Altay Uranghay Mongol herders alternate between sedentary subsistence farming and nomadic pastoralism. The paper looks first at the ways people negotiate these swings between different lifestyles and livelihood options. Second, it considers the environmental changes that result from this uncertainty, and particularly the changing patterns of grassland management in the area. Special attention is given to discussion of the complex impact of the national and regional development strategies and of the ways in which those strategies affect the economic and cultural responses of the local community. Study findings suggest a correlation between cultural fragmentation, which undermines grassland management institutions, and grassland fragmentation and pasture degradation.
Resettlement as Development and Progress? Eight Years On: Review of Emerging Social and Development Impacts of an 'Ecological Resettlement' Project in Tibet Autonomous Region, China
Authors: Tashi Gongbo , Foggin Marc 
Published: December 2012

Abstract
The relocation of rural people away from marginal or fragile lands is an increasingly common approach used in China to achieve environmental protection and development objectives. However at present few studies have been made of the social impacts of such resettlement projects in China. Several key social dimensions of a significant resettlement project in the Tibet Autonomous Region are therefore analysed and discussed in this paper. It was specifically posited that the research findings presented here would (1) provide useful guidance for local government offices and government staff workers who are engaged in poverty reduction and agricultural development work; and (2) help to give residents of the community under consideration more voice and opportunity to interact with the outside world. A field survey was designed and led by the lead author in June 2009, with semi-structured interviews and a questionnaire, to ascertain the present situation in the target village and thus help to provide a useful basis for future policy recommendations.
Coordination fiscale dans l'Union Économique et Monétaire Ouest Africaine
Authors: Mansour Mario , Rota-Graziosi Grégoire 
Published: December 2012

Résumé L’Union Économique et Monétaire Ouest Africaine (UEMOA) est l’une des régions du monde où la coordination fiscale entre États souverains est la plus avancée, de jure du moins. Depuis la fin des années 1990, plusieurs directives communautaires ont encadré la fiscalité directe et indirecte des États membres. Cette coordination vise notamment à créer un cadre fiscal propice à l’intégration économique régionale, à assurer la transition fiscale en substituant les recettes de la fiscalité intérieure à celles douanières compromises par la libéralisation des échanges internationaux et à mobiliser les recettes fiscales. L’objet principal de cet article est de présenter l’état actuel de cette coordination fiscale. Nous examinons les directives et règlements pertinents, la coordination de jure , et leur état d’application dans les pays membres, la coordination de facto . Une brève appréciation des recettes fiscales complète cette analyse qui se conclut par quelques observations sur les enjeux principaux de la coordination fiscale dans la région et les leçons apprises. Classification JEL : O1, H2, H7
Réforme et modernisation des douanes en Afrique subsaharienne francophone, 1995-2010
Authors: Montagnat-Rentier Gilles , Parent Gilles 
Published: December 2012

Résumé Cet article expose les grandes lignes des réformes de modernisation des douanes réalisées dans les pays francophones d’Afrique subsaharienne depuis le milieu des années 1990. Il met également en évidence les problèmes non encore résolus de ce processus. Des progrès sont enregistrés en matière d’automatisation des opérations et de procédures, avec des efforts importants et constants pour mobiliser les recettes douanières et améliorer la facilitation du commerce dans un certain nombre de pays. Cependant, le rythme et l’étendue de la modernisation restent insuffisants, particulièrement en ce qui concerne le développement des contrôles douaniers et la capacité de lutte contre la fraude, le renforcement des ressources opérationnelles, et l’amélioration de la gestion et de l’encadrement des services. Les constats suggèrent qu’un fort engagement des autorités dans la réforme, des transformations dans l’organisation et la gestion, une assistance technique et une gestion de projet adéquates, ainsi que la mise en œuvre effective des normes douanières modernes sont essentiels à l’accélération de la modernisation des douanes en Afrique subsaharienne francophone. Classification JEL : H29, O57
Previous exposure to other males leads to prolonged copulation by a predatory true bug (Hemiptera: Heteroptera: Anthocoridae)
Authors: Horton David R. 
Published: November 2012

AbstractMating pairs ofAnthocoris whiteiReuter (Hemiptera: Heteroptera: Anthocoridae) irregularly exhibit copulations exceeding five hours in duration. In other Heteroptera, male-biased sex ratios or high densities of male conspecifics may lead to prolonged copulation. I tested whether exposure to conspecific males preceding access to females led to prolonged copulations byA. whitei. Copulations in which the male had been exposed to other males were significantly longer (by 60+ minutes) than copulations in which the male had not been exposed to other males. Durations exceeded five hours in several pairings following exposure to other males. Almost 75% of copulations in which males had not been exposed to other males were <100 minutes in duration, whereas only 22%–29% of copulations involving males that had been exposed to other males were <100 minutes in duration. Atypically long copulations by this species may be a form of postinsemination mate guarding to prevent insemination of a guarded female by other males.
Complete Dependence on IRAK4 Kinase Activity in TLR2, but Not TLR4, Signaling Pathways Underlies Decreased Cytokine Production and Increased Susceptibility to Streptococcus pneumoniae Infection in IRAK4 Kinase–Inactive Mice
Authors: Pennini Meghan E. , Perkins Darren J. , Salazar Andres M. , Lipsky Michael , Vogel Stefanie N. 
Published: December 2012

Abstract
IRAK4 is critical for MyD88-dependent TLR signaling, and patients with Irak4 mutations are extremely susceptible to recurrent bacterial infections. In these studies, mice homozygous for a mutant IRAK4 that lacks kinase activity (IRAK4KDKI) were used to address the role of IRAK4 in response to TLR agonists or bacterial infection. IRAK4KDKI macrophages exhibited diminished responsiveness to the TLR4 agonist LPS and little to no response to the TLR2 agonist Pam3Cys compared with wild-type macrophages as measured by cytokine mRNA, cytokine protein expression, and MAPK activation. Importantly, we identified two kinases downstream of the MAPKs, MNK1 and MSK1, whose phosphorylation is deficient in IRAK4KDKI macrophages stimulated through either TLR2 or TLR4, suggesting that IRAK4 contributes to TLR signaling beyond the initial phosphorylation of MAPKs. Additionally, IRAK4KDKI macrophages produced minimal cytokine mRNA expression in response to the Gram-positive bacteria Streptococcus pneumoniae and Staphylococcus aureus compared with WT cells, and IRAK4KDKI mice exhibited increased susceptibility and decreased cytokine production in vivo upon S. pneumoniae infection. Treatment of infected mice with a complex of polyinosinic-polycytidylic acid with poly-L-lysine and carboxymethyl cellulose (Hiltonol), a potent TLR3 agonist, significantly improved survival of both WT and IRAK4KDKI mice, thereby providing a potential treatment strategy in both normal and immunocompromised patients.