bluuebunny/crossref_metadata_2025_split huggingface dataset:
Designing a New Class of Bases for Nucleic Acid Quadruplexes and Quadruplex‐Active Ligands
Authors: Bazzi Sophia , Novotný Jan , Yurenko Yevgen P. , Marek Radek 
Published: June 2015

AbstractA new class of quadruplex nucleobases, derived from 3‐deazaguanine, has been designed for various applications as smart quadruplex ligands as well as quadruplex‐based aptamers, receptors, and sensors. An efficient strategy for modifying the guanine quadruplex core has been developed and tested by using quantum chemistry methods. Several potential guanine derivatives modified at the 3‐ or 8‐position or both are analyzed, and the results compared to reference systems containing natural guanine. Analysis of the formation energies (BLYP‐D3(BJ)/def2‐TZVPP level of theory, in combination with the COSMO model for water) in model systems consisting of two and three stacked tetrads with Na+/K+ion(s) inside the internal channel indicates that the formation of structures with 3‐halo‐3‐deazaguanine bases leads to a substantial gain in energy, as compared to the corresponding reference guanine complexes. The results cast light on changes in the noncovalent interactions (hydrogen bonding, stacking, and ion coordination) in a quadruplex stem upon modification of the guanine core. In particular, the enhanced stability of the modified quadruplexes was shown to originate mainly from increased π–π stacking. Our study suggests the 3‐halo‐3‐deazaguanine skeleton as a potential building unit for quadruplex systems and smart G‐quadruplex ligands.
Proton Order–Disorder Phenomena in a Hydrogen‐Bonded Rhodium–η5‐Semiquinone Complex: A Possible Dielectric Response Mechanism
Authors: Mitsumi Minoru , Ezaki Kazunari , Komatsu Yuuki , Toriumi Koshiro , Miyatou Tatsuya , Mizuno Motohiro , Azuma Nobuaki , Miyazaki Yuji , Nakano Motohiro , Kitagawa Yasutaka , Hanashima Takayasu , Kiyanagi Ryoji , Ohhara Takashi , Nakasuji Kazuhiro 
Published: June 2015

AbstractA newly synthesized one‐dimensional (1D) hydrogen‐bonded (H‐bonded) rhodium(II)–η5‐semiquinone complex, [Cp*Rh(η5‐p‐HSQ‐Me4)]PF6 ([1]PF6; Cp*=1,2,3,4,5‐pentamethylcyclopentadienyl; HSQ=semiquinone) exhibits a paraelectric–antiferroelectric second‐order phase transition at 237.1 K. Neutron and X‐ray crystal structure analyses reveal that the H‐bonded proton is disordered over two sites in the room‐temperature (RT) phase. The phase transition would arise from this proton disorder together with rotation or libration of the Cp* ring and PF6− ion. The relative permittivity εb′ along the H‐bonded chains reaches relatively high values (ca., 130) in the RT phase. The temperature dependence of 13C CP/MAS NMR spectra demonstrates that the proton is dynamically disordered in the RT phase and that the proton exchange has already occurred in the low‐temperature (LT) phase. Rate constants for the proton exchange are estimated to be 10−4–10−6 s in the temperature range of 240–270 K. DFT calculations predict that the protonation/deprotonation of [1]+ leads to interesting hapticity changes of the semiquinone ligand accompanied by reduction/oxidation by the π‐bonded rhodium fragment, producing the stable η6‐hydroquinone complex, [Cp*Rh3+(η6‐p‐H2Q‐Me4)]2+ ([2]2+), and η4‐benzoquinone complex, [Cp*Rh+(η4‐p‐BQ‐Me4)] ([3]), respectively. Possible mechanisms leading to the dielectric response are discussed on the basis of the migration of the protonic solitons comprising of [2]2+ and [3], which would be generated in the H‐bonded chain.
[3+2] Redox‐Neutral Cycloaddition of Nitrocyclopropanes with Styrenes by Visible‐Light Photocatalysis
Authors: Wang Chengfeng , Ren Xiang , Xie Hujun , Lu Zhan 
Published: June 2015

AbstractThe first nitro‐group‐initiated redox‐neutral [3+2] cycloaddition of nitrocyclopropanes with alkenes by using visible‐light‐absorbing transition‐metal complexes was reported. High diastereoselectivities were observed for two quaternary carbon centers on the ring and validated by DFT calculations. Spiro‐ or polycyclic structures can be constructed smoothly. Cyclic γ‐amino acid derivatives and polysubstituted cyclic amino alcohols can be obtained easily through reduction of the nitro group.
Octahedral Chiral‐at‐Metal Iridium Catalysts: Versatile Chiral Lewis Acids for Asymmetric Conjugate Additions
Authors: Shen Xiaodong , Huo Haohua , Wang Chuanyong , Zhang Bo , Harms Klaus , Meggers Eric 
Published: June 2015

AbstractOctahedral iridium(III) complexes containing two bidentate cyclometalating 5‐tert‐butyl‐2‐phenylbenzoxazole (IrO) or 5‐tert‐butyl‐2‐phenylbenzothiazole (IrS) ligands in addition to two labile acetonitrile ligands are demonstrated to constitute a highly versatile class of asymmetric Lewis acid catalysts. These complexes feature the metal center as the exclusive source of chirality and serve as effective asymmetric catalysts (0.5–5.0 mol % catalyst loading) for a variety of reactions with α,β‐unsaturated carbonyl compounds, namely Friedel–Crafts alkylations (94–99 % ee), Michael additions with CH‐acidic compounds (81–97 % ee), and a variety of cycloadditions (92–99 % ee with high d.r.). Mechanistic investigations and crystal structures of an iridium‐coordinated substrates and iridium‐coordinated products are consistent with a mechanistic picture in which the α,β‐unsaturated carbonyl compounds are activated by two‐point binding (bidentate coordination) to the chiral Lewis acid.
Reversible Doping of a Dithienothiophene‐Based Conjugated Microporous Polymer
Authors: Bildirir Hakan , Osken Ipek , Ozturk Turan , Thomas Arne 
Published: June 2015

AbstractDithienothiophene (DTT) based conjugated microporous polymers (CMPs) were synthesized by bulk and electrochemical oxidative polymerizations. Spectroelectrochemical measurements showed that DTT‐CMP can be reversibly oxidized and reduced, accompanied by a significant change of the absorption properties making the material interesting for electrochromic devices. Reversible doping and dedoping of the bulk polymer network was also observed using iodine and ammonia, respectively. Nitrogen gas sorption measurements of the neutral, doped, and dedoped polymer networks indicated the presence of iodide species within the pores, and the conductivity of the networks is highly increased upon doping with iodine. The introduction of the strong electron donor DTT into a conjugated porous network, and the ability for redox switching, make DTT‐CMPs interesting materials for organo(opto)electronic devices and sensors.
Spatially Controlled Out‐of‐Equilibrium Host–Guest System under Electrochemical Control
Authors: Krabbenborg Sven O. , Veerbeek Janneke , Huskens Jurriaan 
Published: June 2015

AbstractSelf‐assembly to create molecular and nanostructures is typically performed at the thermodynamic minimum. To achieve dynamic functionalities, such as adaptability, internal feedback, and self‐replication, there is a growing focus on out‐of‐equilibrium systems. This report presents the dynamic self‐assembly of an artificial host–guest system at an interface, under control by a dissipative electrochemical process using (electrical) energy, resulting in an out‐of‐equilibrium system exhibiting a supramolecular surface gradient. The gradient, its steepness, rate of formation, and complex surface composition after backfilling, as well as the surface compositions after switching between the different states of the system, are assessed and supported by modelling. Our method shows for the first time an artificial surface‐confined out‐of‐equilibrium system. The electrochemical process parameters provide not only control over the system in time, but also in space.
BF3·Et2O Promoted Sulfuration of Steroidal Sapogenins
Authors: Wang Jun , Wu Jingjing , Tian Weisheng 
Published: June 2015

AbstractA reaction between steroidal sapogenins and hydrogen sulfide promoted by BF3·Et2O is described. The thiodiosgenin and thiotigogenin comprising a sulfur atom on the F ring can be easily afforded in one step under this mild reaction condition. Furthermore, a hypothetical mechanism is also shown.
Hydrogen Storage Materials for Mobile and Stationary Applications: Current State of the Art
Authors: Lai Qiwen , Paskevicius Mark , Sheppard Drew A. , Buckley Craig E. , Thornton Aaron W. , Hill Matthew R. , Gu Qinfen , Mao Jianfeng , Huang Zhenguo , Liu Hua Kun , Guo Zaiping , Banerjee Amitava , Chakraborty Sudip , Ahuja Rajeev , Aguey‐Zinsou Kondo‐Francois 
Published: June 2015

AbstractOne of the limitations to the widespread use of hydrogen as an energy carrier is its storage in a safe and compact form. Herein, recent developments in effective high‐capacity hydrogen storage materials are reviewed, with a special emphasis on light compounds, including those based on organic porous structures, boron, nitrogen, and aluminum. These elements and their related compounds hold the promise of high, reversible, and practical hydrogen storage capacity for mobile applications, including vehicles and portable power equipment, but also for the large scale and distributed storage of energy for stationary applications. Current understanding of the fundamental principles that govern the interaction of hydrogen with these light compounds is summarized, as well as basic strategies to meet practical targets of hydrogen uptake and release. The limitation of these strategies and current understanding is also discussed and new directions proposed.
Soluble flagellin coimmunization attenuates Th1 priming to Salmonella and clearance by modulating dendritic cell activation and cytokine production
Authors: Flores‐Langarica Adriana , Bobat Saeeda , Marshall Jennifer L. , Yam‐Puc Juan Carlos , Cook Charlotte N. , Serre Karine , Kingsley Robert A. , Flores‐Romo Leopoldo , Uematsu Satoshi , Akira Shizuo , Henderson Ian R. , Toellner Kai M. , Cunningham Adam F. 
Published: June 2015

Soluble flagellin (sFliC) from Salmonella Typhimurium (STm) can induce a Th2 response to itself and coadministered antigens through ligation of TLR5. These properties suggest that sFliC could potentially modulate responses to Th1 antigens like live STm if both antigens are given concurrently. After coimmunization of mice with sFliC and STm there was a reduction in Th1 T cells (T‐bet+IFN‐γ+ CD4 T cells) compared to STm alone and there was impaired clearance of STm. In contrast, there was no significant defect in the early extrafollicular B‐cell response to STm. These effects are dependent upon TLR5 and flagellin expression by STm. The mechanism for these effects is not related to IL‐4 induced to sFliC but rather to the effects of sFliC coimmunization on DCs. After coimmunization with STm and sFliC, splenic DCs had a lower expression of costimulatory molecules and profoundly altered kinetics of IL‐12 and TNFα expression. Ex vivo experiments using in vivo conditioned DCs confirmed the effects of sFliC were due to altered DC function during a critical window in the coordinated interplay between DCs and naïve T cells. This has marked implications for understanding how limits in Th1 priming can be achieved during infection‐induced, Th1‐mediated inflammation.
Transforming ecosystems: When, where, and how to restore contaminated sites
Authors: Rohr Jason R , Farag Aïda M , Cadotte Marc W , Clements William H , Smith James R , Ulrich Cheryl P , Woods Richard 
Published: June 2015

Abstract
Chemical contamination has impaired ecosystems, reducing biodiversity and the provisioning of functions and services. This has spurred a movement to restore contaminated ecosystems and develop and implement national and international regulations that require it. Nevertheless, ecological restoration remains a young and rapidly growing discipline and its intersection with toxicology is even more nascent and underdeveloped. Consequently, we provide guidance to scientists and practitioners on when, where, and how to restore contaminated ecosystems. Although restoration has many benefits, it also can be expensive, and in many cases systems can recover without human intervention. Hence, the first question we address is: “When should we restore contaminated ecosystems?” Second, we provide suggestions on what to restore—biodiversity, functions, services, all 3, or something else—and where to restore given expected changes to habitats driven by global climate change. Finally, we provide guidance on how to restore contaminated ecosystems. To do this, we analyze critical aspects of the literature dealing with the ecology of restoring contaminated ecosystems. Additionally, we review approaches for translating the science of restoration to on-the-ground actions, which includes discussions of market incentives and the finances of restoration, stakeholder outreach and governance models for ecosystem restoration, and working with contractors to implement restoration plans. By explicitly considering the mechanisms and strategies that maximize the success of the restoration of contaminated sites, we hope that our synthesis serves to increase and improve collaborations between restoration ecologists and ecotoxicologists and set a roadmap for the restoration of contaminated ecosystems. Integr Environ Assess Manag 2016;12:273–283. © 2015 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of SETAC
Key Points
We merge insights from ecological and economic theory and on-the-ground restoration activities to provide guidance on what endpoints should be targeted for restoration in contaminated ecosystems and when, where, and how to restore ecosystems degraded by contaminants. We encourage practitioners to consider restoration as early as possible (i.e., before injury or before remediation) and to restore both structural and functional endpoints. We also promote consideration of broader landscape and seascape contexts and new ideas and approaches that can overcome the scientific and financial limitations of restoration. We urge more reciprocal transfer of knowledge among theorist and practitioners and academics, industry, government, tribal organizations, NGOs and the public to improve the science of restoration.
Non‐clinical safety evaluation of repeated intramuscular administration of the AS15 immunostimulant combined with various antigens in rabbits and cynomolgus monkeys
Authors: Garçon N. , Silvano J. , Kuper C. F. , Baudson N. , Gérard C. , Forster R. , Segal L. 
Published: June 2015

AbstractCombination of tumor antigens with immunostimulants is a promising approach in cancer immunotherapy. We assessed animal model toxicity of AS15 combined with various tumor antigens: WT1 (rabbits), or p501, dHER2 and recPRAME (cynomolgus monkeys), administered in seven or 20 dose regimens versus a saline control. Clinical and ophthalmological examinations, followed by extensive post‐mortem pathological examinations, were performed on all animals. Blood hematology and biochemistry parameters were also assessed. Antigen‐specific antibody titers were determined by enzyme‐linked immunosorbent assay. Additional assessments in monkeys included electrocardiography and immunohistochemical evaluations of the p501 expression pattern. Transient increases in body temperature were observed 4 h or 24 h after injections of recPRAME + AS15 and dHER2 + AS15. Edema and erythema were observed up to 1 week after most injections of recPRAME + AS15 and all injections of dHER2 + AS15. No treatment‐related effects were observed for electrocardiography parameters. Mean fibrinogen levels were significantly higher in all treated groups compared to controls, but no differences could be observed at the end of the treatment‐free period. Transient but significant differences in biochemistry parameters were observed post‐injection: lower albumin/globulin ratios (p501 + AS15), and higher bilirubin, urea and creatinine (dHER2 + AS15). Pathology examinations revealed significant increases in axillary lymph node mean weights (recPRAME + AS15) compared to controls. A 100% seroconversion rate was observed in all treated groups, but not in controls. p501 protein expression was observed in prostates of all monkeys from studies assessing p501 + AS15. These results suggest a favorable safety profile of the AS15‐containing candidate vaccines, supporting the use of AS15 for clinical development of potential anticancer vaccines. Copyright © 2015 The Authors. Journal of Applied Toxicology Published by John Wiley & Sons Ltd.
Ultrastructure of male reproductive system of Eurydema ventrale Kolenati 1846 (Heteroptera: Pentatomidae)
Authors: Özyurt Nurcan , Candan Selami , Suludere Zekiye 
Published: June 2015

ABSTRACTThe male reproductive system of Eurydema ventrale Kolenati 1846 is studied morphologically and histologically by using light, scanning and transmission electron microscopes. The reproductive system of the male E.ventrale consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands, a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The testicular follicles have three different development zones (growth zone, maturation zone, and differentiation zone). The testes are connected to the seminal vesicles by the vas deferens that is a specialized in sperm storage. Sperm have an elongated head and a tail (flagellum) with an axonema and two mitochondrial derivatives. Vas deferens and seminal vesicles are fine, long, and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius, which is balloon shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which is connected to the aedeagus. Microsc. Res. Tech. 78:643–653, 2015. © 2015 Wiley Periodicals, Inc.
Systematic study of cell isolation from bovine nucleus pulposus: Improving cell yield and experiment reliability
Authors: Lee Juliana T. Y. , Cheung Kenneth M. C. , Leung Victor Y. L. 
Published: June 2015

ABSTRACTDifferences in matrix compositions in human nucleus pulposus (NP) clinical samples demand different cell isolation protocols for optimal results but there is no clear guide about this to date. Sub‐optimal protocols may result in low cell yield, limited reliability of results or even failure of experiments. Cell yield, viability and attachment of cells isolated from bovine NP tissue with different protocols were estimated by cell counting, Trypan blue staining and cell culturing respectively. RNA was extracted from isolated cells and quantified by Nanodrop spectrometry and RT‐qPCR. Higher collagenase concentration, longer digestion duration and pronase pre‐treatment increased the cell yield. Cell viability remained high (<5% dead cells) even after 0.2% collagenase treatment for overnight. NP cells remained to have high ACAN, COL2A1, CDH2, KRT18, and KRT19 expression compared to muscle cells for different cell isolation conditions tested. Digestion by collagenase alone without the use of pronase could isolate cells from human degenerated NP tissue but clusters of cells were observed. We suggest the use of the disappearance of tissue as an indirect measure of cells released. This study provides a guide for researchers to decide the parameters involved in NP cell isolation for optimal outcome. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1743–1755, 2015.
Effects of Tillage Methods on Soil Carbon and Wind Erosion
Authors: Gao Yong , Dang Xiaohong , Yu Yi , Li Yubao , Liu Yang , Wang Ji 
Published: June 2015

AbstractCurrent interest in soil‐conserving tillage in China has developed from the concern that Chinese agricultural land loses 73·8 Mg C annually. Previous research has shown that changing from conventional tillage to conservation tillage field management increases soil C sequestration. The aim of this study is to determine if no tillage with stubble retention can reduce soil carbon loss and erosion compared with conventional tillage for a cornfield in northern China. We found that soil organic C storage (kg m−2) under conservation tillage in the form of no post‐harvest tillage with stubble retention increased from 28% to 62% in the soil depths of 0–30 cm (p < 0·01) compared with the conventional tillage. Retaining post‐harvest stubble with a height of 30 cm and incorporating the stubble into the soil before seeding the next spring increased soil organic carbon the most. Carbon storage (kg ha−1) in aboveground and belowground biomass of the corn plants in seedling and harvest stages was significantly greater (p < 0·01) with stubble retention treatments than with conventional tillage. Carbon content in root biomass in all treatments with stubble retention was significantly greater than that with conventional tillage. Soil erosion estimates in the study area under conservation tillage with stubble retention was significantly lower than that under conventional tillage during the monitoring period. Given the complexities of agricultural systems, it is unlikely that one ideal farming practice is suitable to all soils or different climate conditions, but stubble retention during harvesting and incorporation of the stubble into soil in the next spring appears to be the best choice in the dry northern China where farmlands suffer serious wind erosion. Copyright © 2015 John Wiley & Sons, Ltd.
Biomimetic Mussel Adhesive Inspired Anchor to Design ZnO@Poly(3‐Hexylthiophene) Hybrid Core@Corona Nanoparticles
Authors: Awada Hussein , Mezzasalma Leila , Blanc Sylvie , Flahaut Delphine , Dagron‐Lartigau Christine , Lyskawa Joël , Woisel Patrice , Bousquet Antoine , Billon Laurent 
Published: June 2015

The functionalization of zinc oxide (ZnO) nanoparticles by poly(3‐hexylthiophene) (P3HT) brush is completed by the combination of a mussel inspired biomimetic anchoring group and Huisgen cyclo‐addition “click chemistry.” Herein, the direct coupling of an azide modified catechol derivative with an alkyne end‐functionalized P3HT is described. This macromolecular binding agent is used to access core@corona ZnO@P3HT with a stable and homogeneous conjugated organic corona. Preliminary photoluminescence measurement proves an efficient electron transfer from the donor P3HT to the acceptor ZnO nanoparticles upon grafting, thus demonstrating the potential of such a combination in organic electronics.
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Detrimental effects of electron beam irradiation on the cowpea bruchid Callosobruchus maculatus
Authors: Sang Wen , Speakmon Mickey , Zhou Lan , Wang Yu , Lei Chaoliang , Pillai Suresh D , Zhu‐Salzman Keyan 
Published: June 2015

AbstractBACKGROUNDElectron beam (eBeam) irradiation technology is an environmentally friendly, chemical‐free alternative for disinfesting insect pests of stored grains. The underlying hypothesis is that specific doses of eBeam will have defined detrimental effects on the different life stages. We evaluated the effects of eBeam exposure in a range of doses (0.03–0.12 kGy) on the development of the cowpea bruchid (Callosobruchus maculatus) at various stages of its life cycle.RESULTSDifferential radiosensitivity was detected during egg development. Early and intermediate stages of eggs never hatched after exposure to a dose of 0.03 kGy, whereas a substantial portion of black‐headed (i.e. late) eggs survived irradiation even at 0.12 kGy. However, further development of the hatched larvae was inhibited. Although midgut protein digestion remained intact, irradiated larvae (0.06 kGy or higher) failed to develop into normal living adults; rather, they died as pupae or abnormally eclosed adults, suggesting a detrimental effect of eBeam on metamorphosis. Emerged irradiated pupae had shorter longevity and were unable to produce any eggs at 0.06 kGy or higher. At this dose range, eggs laid by irradiated adults were not viable. eBeam treatment shortened adult longevity in a dose‐dependent manner. Reciprocal crosses indicated that females were more sensitive to eBeam exposure than their male counterparts. Dissection of the female reproductive system revealed that eBeam treatment prevented formation of oocytes.CONCLUSIONeBeam irradiation has very defined effects on cowpea bruchid development and reproduction. A dose of 0.06 kGy could successfully impede cowpea burchid population expansion. This information can be exploited for post‐harvest insect control of stored grains. © 2015 Society of Chemical Industry