bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Biologically Relevant Small Molecules Containing Selenium. Part C. Miscellaneous Biological Activities
Authors: Braga Antonio L. , Rafique Jamal 
Published: April 2014

AbstractOrganoselenium compounds are known as antioxidants, antithyroid, antinociceptive, antidepressant, thioredoxin reductase (TrxR) mimetic agents with a variety of protective behaviors (e.g. cardioprotective, neuroprotective and hepatoprotective). In addition. they can be used as virueides, bactericides, fungicides, cytokine inducers and immunomodulators. The chemical and biological activity of organose leniumcompounds is discussed herein.The strategies and methods for the preparation of biologically relevant small molecules containing selenium are reviewed in this chapter. The unique redox properties of selenium confer catalytic activity to organoselenium compounds and influence their biological properties as well as the methods selected for their preparation. The approaches available to obtain organoselenium compounds, including reaction of elemental selenium or diselenides with different types of carbanions or reaction of organic electrophiles with selenolate anions generated by different methods, are disclosed in this chapter.
Heteroatom‐substitued Dioxetanes and their Emerging Biomedical Applications
Authors: NKEPANG GREGORY , YOU YOUNGJAE 
Published: April 2014

AbstractHeteroatom‐substituted dioxetanes are one subclass of dioxetanes that have at least one heteroatom (such as O, S, N) at its two carbons of dioxetane structures. These are readily formed from the [2+2] cycloaddition reaction of heteroatom‐substituted alkenes and singlet oxygen (1O2). Due to their unique characteristics, such as chemiluminescence and spontaneous cleavage, heteroatom‐substituted dioxetanes have been used for a number of biomedical applications, for example biomedical analyses and light‐controlled drug release. A number of review papers and book chapters have been published for the biomedical analyses of chemiluminescence. However, no comprehensive review or book chapter for the applications to light‐controlled drug release have yet been published, although there have been very significant and interesting advances in the field in the last couple of years. In this chapter, we focus mainly on a new and exciting application of dioxetanes for light‐controlled drug release. In the latter part of this section, we also introduce briefly another new interesting application of dioxetane chemistry for hydrogen peroxide (H2O2) imaging.
1,2‐Dioxatrisulfane (thiaperoxide) intermediates in type I and II photooxygenation reactions
Authors: CLENNAN EDWARD L. 
Published: April 2014

AbstractThis review focuses on a discussion of labile metastable sulfur‐based peroxides (persulfoxides‐R2S+OO−; 3‐membered SOO ring thiadioxiranes‐c‐R2SO2; hydroperoxy sulfonium ylides‐R(R′CH)S+OO−; and, peroxy sulfuranes‐R2S(OR′)OOR′′) that have been observed or implicated in Type I and II photooxygenation reactions. Evidence for formation and computational structures of these novel intermediates is presented.
Peroxide Explosives
Authors: Klapötke Thomas M. , Wloka Thomas 
Published: April 2014

AbstractTriacetone triperoxide (TATP) is formed from acetone in sulfuric acid solution when acted upon hydrogen peroxide. Like most other organic peroxides TATP has very high impact, friction and thermal sensitivity. TATP displays the properties of a primary explosive. For this reason and because of its tendency to sublime it is not used in practice (apart from terrorist and suicide bomber activities). Because of the use of TATP by terrorists, a reliable and fast detection of this material is desirable. In addition to conventional analytical methods such as mass spectrometry and UV (ultra violet) spectroscopy specially trained explosive detection dogs (EDD) play an important role in the detection of organic peroxides. Typical organic peroxides, which have or may be used by terrorists, so‐called homemade explosives (HMEs) discussed in this chapter are: TATP (triacetone triperoxide), HMTD (hexamethylene triperoxide diamine), MEKP (methyl ethyl ketone peroxide) and DADP (diacetone diperoxide).
The Use of Hydrogen Peroxide for Disinfection and Sterilization Applications
Authors: McDonnell Gerald 
Published: April 2014

AbstractHydrogen peroxide is a widely used antimicrobial chemical. It is used in both liquid and gas form for preservative, disinfection and sterilization applications. Its advantages include its potent and broad spectrum antimicrobial activity, flexibility in use, and safety profile in comparison to other microbiocides. Hydrogen peroxide has been shown to be effective against all forms of microorganisms, including dormant forms with known high resistance such as bacterial spores and protozoal cysts, and also infectious proteins such as prions depending on the specific use of the chemical. It also has advantages with regard to its toxicity and environmental profile. However, overall, the effective and safe use of hydrogen peroxide depends on the way it is used, in particular the concentration. In aqueous form it is used in solution with water directly as a preservative, in products as a preservative or on the skin, including in wounds, and on inanimate surfaces. Recent technology advances have been made in the formulation of peroxide with other chemicals to enhance the antimicrobial activity at lower target concentrations of the active agent. Hydrogen peroxide gas is also widely used for disinfection and sterilization. The gas form is particularly effective in comparison liquid forms and at lower concentrations. Hydrogen peroxide gas processes have become popular alternatives to other chemical and physical based antimicrobial methods due to its rapid efficacy, low temperature, compatibility with surface materials and limited toxicity concerns. The mechanism of action of hydrogen peroxide is not fully understood and is associated with its oxidation activity. The oxidation of the various molecules that constitute microorganisms will lead to significant disruptions in structure/function and the loss of viability or infectivity. Despite this generalization, liquid preparations, formulations and the gas form of hydrogen peroxide can show remarkable differences in their antimicrobial effects, such as their attack on proteins, nucleic acids, and lipids. The general mechanisms of action of hydrogen peroxide significantly reduce any risk of the development of resistance to the biocide over time, unlike many other types of anti‐infective drugs or biocides. Microbial resistance to peroxide is primarily due to the various natural differences observed in the growth and survival of microorganisms but can be overcome by the right process and application with hydrogen peroxide‐containing products. The many benefits in the use of liquid and gas hydrogen peroxide for antimicrobial applications make it attractive for future and optimal developments with this microbiocide.
Linear Accelerators
Authors: Jameson Robert , Bisognano Joseph , Lapostolle Pierre 
Published: April 2014

AbstractLinear accelerators, in which particles are accelerated along a straight path, are a fundamental tool for a perhaps surprisingly wide variety of practical and research applications that affect our daily lives, as a source of energetic particles in equipment for medical, biological, and industrial applications, including dental X‐rays, industrial irradiation, radiotherapy, medical tool sterilization, food conservation, and baggage inspection, and provide intense beams of neutrons or photons for use in condensed matter, materials, and biological sciences and applications. In the future, LINACs will enable methods to deal with radioactive waste and other societally important applications. The general principles, brief history, and overview of the various types of linear accelerators are outlined in this chapter.
Nuclear Structure
Authors: Jolie Jan 
Published: April 2014

AbstractThe basic properties of atomic nuclei are reviewed. Experimental measurements of nuclear masses give access to the nuclear binding energies and are essential to understand nuclear radioactivity and basic properties of atomic nuclei via the semiempirical mass formula. The presence of charges in the atomic nuclei leads to the possibility to measure the nuclear charge distribution. Emphasis is put on the electromagnetic properties of nuclear excitations allowing the determination of several nuclear moments of states and of electromagnetic transition rates in between these states. Following an overview of the observed properties of excited states in atomic nuclei, four nuclear models used to describe the structure of the atomic nucleus are introduced. They are the spherical and deformed shell models, the collective model, and the interacting boson model.
Exotic Nuclear Beam Facilities
Authors: Geissel Hans , Huyse Mark , Münzenberg Gottfried , Van Duppen Piet 
Published: April 2014

AbstractThe knowledge of exotic nuclei properties is essential for the understanding of the strong interaction and the element synthesis in the cosmos. Exotic nuclides are short lived and therefore, cannot be found on Earth but are still produced in stars. To study such atomic nuclei, one has to produce them with nuclear reactions in the laboratory and to separate them with special tools, from all the inevitable abundant background. The production and separation of these exotic nuclear beams can be performed with in‐flight or isotope separation on line facilities or hybrid systems of these two main scenarios. An exotic nuclear beam facility consists mainly of a combination of the production and the separation part as well as a post‐acceleration unit for the case that the experiment needs beams with kinetic energies and emittances different from that what the separator can provide. The challenge to investigate exotic nuclei is that they are characterized by very low production cross sections and short half‐lives. Different reactions to create exotic nuclei, and the physics and techniques of modern separation methods are discussed. We present the recent progress made in studying exotic nuclei by new accelerator developments, powerful separators combined with high‐resolution spectrometers and storage devices, and efficient detector systems. This chapter ends with the description of some recent discoveries with exotic nuclei and the motivation for the next‐generation facilities.
Superheavy Nuclei
Authors: Hofmann Sigurd 
Published: April 2014

The existence of nuclei at the limits of stability is determined by nuclear structure. The nuclear shell model, which effectively describes nuclear properties and the underlying shell structure all over the chart of nuclei, predicts the next closed shells or subshells beyond the double magic

208
Pb

at proton numbers

Z

= 114, 120, or 126, and at neutron number

N

= 184. Although the strength of the shells is difficult to calculate, an increased stability is expected for nuclei having these numbers of protons and neutrons. Experiments performed at various major laboratories were aiming to produce these “superheavy nuclei.” Described are the results of these experiments covering reaction studies and measurements of the decay properties of the nuclei produced. A comparison of the data with predictions of theoretical models reveals an increased stability for deformed nuclei at

Z

= 108 and

N

= 162, and for spherical nuclei having proton numbers

Z

= 114–118 and neutron numbers approaching

N

= 184. It is shown that, in general, the theoretical predictions are confirmed by experiments, although details of the structure of the island of superheavy nuclei remain to be explored.
The Proton
Authors: Caldwell Allen 
Published: April 2014

Abstract
This chapter describes the historical development and current state of knowledge concerning the proton. The understanding of the proton has gone through several revolutions in the last 100 years, and we start with a short review of this history. The central part of the text then describes the proton in terms of its constituents and the current state of knowledge on this structure is outlined. Although we have acquired a wealth of knowledge concerning the proton, many fascinating research questions remain. As shown at the end of the chapter, very different pictures of the basic physics arise depending on the frame of reference one chooses to describe the physics.
Fool Me Twice: The Consequences of Reading (and Rereading) Inaccurate Information
Authors: Jacovina Matthew E. , Hinze Scott R. , Rapp David N. 
Published: April 2014

SummaryReaders frequently encounter inaccuracies in texts that contradict what they should know to be true. The current project examined readers' moment‐by‐moment processing of inaccuracies and whether any difficulty with such material is reduced when readers are already familiar with accurate versions of that content. In two experiments, participants read stories that either accurately or inaccurately described the outcome of a well‐known historic event. Preceding story contexts supported accurate outcomes or introduced suspense to create uncertainty about outcome likelihoods. During initial readings, participants took longer to read inaccurate than accurate outcomes. But this difficulty was substantially reduced when suspenseful contexts called into question the likelihood of well‐known outcomes. Similar reading patterns emerged when participants read the exact same material after week‐long and 5‐minute delays. These results indicate that biasing contexts can influence readers' processing of inaccuracies for even familiar events. Rereading proves insufficient for encouraging reliance on accurate prior knowledge. Copyright © 2014 John Wiley & Sons, Ltd.
A Molecular Approach to Self‐Supported Cobalt‐Substituted ZnO Materials as Remarkably Stable Electrocatalysts for Water Oxidation
Authors: Pfrommer Johannes , Lublow Michael , Azarpira Anahita , Göbel Caren , Lücke Marcel , Steigert Alexander , Pogrzeba Martin , Menezes Prashanth W. , Fischer Anna , Schedel‐Niedrig Thomas , Driess Matthias 
Published: April 2014

AbstractIn regard to earth‐abundant cobalt water oxidation catalysts, very recent findings show the reorganization of the materials to amorphous active phases under catalytic conditions. To further understand this concept, a unique cobalt‐substituted crystalline zinc oxide (Co:ZnO) precatalyst has been synthesized by low‐temperature solvolysis of molecular heterobimetallic Co4−xZnxO4 (x=1–3) precursors in benzylamine. Its electrophoretic deposition onto fluorinated tin oxide electrodes leads after oxidative conditioning to an amorphous self‐supported water‐oxidation electrocatalyst, which was observed by HR‐TEM on FIB lamellas of the EPD layers. The Co‐rich hydroxide‐oxidic electrocatalyst performs at very low overpotentials (512 mV at pH 7; 330 mV at pH 12), while chronoamperometry shows a stable catalytic current over several hours.
Formation of High‐Valent Iron–Oxo Species in Superoxide Reductase: Characterization by Resonance Raman Spectroscopy
Authors: Bonnot Florence , Tremey Emilie , von Stetten David , Rat Stéphanie , Duval Simon , Carpentier Philippe , Clemancey Martin , Desbois Alain , Nivière Vincent 
Published: April 2014

AbstractSuperoxide reductase (SOR), a non‐heme mononuclear iron protein that is involved in superoxide detoxification in microorganisms, can be used as an unprecedented model to study the mechanisms of O2 activation and of the formation of high‐valent iron–oxo species in metalloenzymes. By using resonance Raman spectroscopy, it was shown that the mutation of two residues in the second coordination sphere of the SOR iron active site, K48 and I118, led to the formation of a high‐valent iron–oxo species when the mutant proteins were reacted with H2O2. These data demonstrate that these residues in the second coordination sphere tightly control the evolution and the cleavage of the OO bond of the ferric iron hydroperoxide intermediate that is formed in the SOR active site.
Enzyme‐Mediated Site‐Specific Bioconjugation of Metal Complexes to Proteins: Sortase‐Mediated Coupling of Copper‐64 to a Single‐Chain Antibody
Authors: Paterson Brett M. , Alt Karen , Jeffery Charmaine M. , Price Roger I. , Jagdale Shweta , Rigby Sheena , Williams Charlotte C. , Peter Karlheinz , Hagemeyer Christoph E. , Donnelly Paul S. 
Published: April 2014

AbstractThe enzyme‐mediated site‐specific bioconjugation of a radioactive metal complex to a single‐chain antibody using the transpeptidase sortase A is reported. Cage amine sarcophagine ligands that were designed to function as substrates for the sortase A mediated bioconjugation to antibodies were synthesized and enzymatically conjugated to a single‐chain variable fragment. The antibody fragment scFvanti‐LIBS targets ligand‐induced binding sites (LIBS) on the glycoprotein receptor GPIIb/IIIa, which is present on activated platelets. The immunoconjugates were radiolabeled with the positron‐emitting isotope 64Cu. The new radiolabeled conjugates were shown to bind selectively to activated platelets. The diagnostic potential of the most promising conjugate was demonstrated in an in vivo model of carotid artery thrombosis using positron emission tomography. This approach gives homogeneous products through site‐specific enzyme‐mediated conjugation and should be broadly applicable to other metal complexes and proteins.
Synthesis and characterization of inherently flame‐retardant and anti‐dripping thermoplastic poly(imides‐urethane)s
Authors: Tang Qiheng , Song Yun , He Jiyu , Yang Rongjie 
Published: April 2014

AbstractA series of thermoplastic poly(imide‐urethane)s (TPIUs), based on 4,4′‐diphenylmethane diisocyanate (MDI) and pyromellitic anhydride (PMDA) as hard segments and poly(tetrahydrofuran) (PTMG) as soft segments, has been prepared by a two‐step polymerization process. The objective of this study is to prepare a type of intrinsically flame‐retardant polyurethane by incorporating PMDA as a flame retardant in the main chains. The thermal behavior and flame retardancies of the TPIUs have been characterized by thermal gravimetric (TG) analysis and limiting oxygen index (LOI), UL‐94 vertical burning, cone calorimeter tests. The results indicate that the TPIUs display outstanding performance. The temperature at 5% mass loss (T5%) and LOI value increase with the hard‐segment contents, while the total heat released (THR) and peak heat release rate (p‐HRR) show the opposite trend. Furthermore, the T5% of TPIU211 (molar ratio: MDI : PTMG : PMDA = 2 : 1 : 1) is 33.2°C higher than that of the conventional thermoplastic polyurethane TPU211 (molar ratio: MDI : PTMG : 1,4‐butanediol = 2 : 1 : 1), and the THR and p‐HRR of TPIU211 are 14.62% and 64.02% lower than the respective parameters of TPU211. In addition, UL‐94 vertical burning tests show that the TPIUs exhibit excellent antidripping effects. The ultimate tensile strengths of the TPIUs reached 23.1−37.6 MPa with increasing hard segment contents, which meets the requirement of mechanical properties with regard to practical use. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40801.
High dielectric constant polyimide derived from 5,5′‐bis[(4‐amino) phenoxy]‐2,2′‐bipyrimidine
Authors: Peng Xinwen , Wu Qiong , Jiang Shaohua , Hanif Muddasir , Chen Shuiliang , Hou Haoqing 
Published: April 2014

ABSTRACTPolyimides (PIs) are highly desirable materials due to their excellent physical, chemical properties, and widespread applications. In this article, a new PI containing bipyrimidine units was prepared from a newly synthesized 5,5′‐bis[(4‐amino) phenoxy]‐2,2′‐bipyrimidine and 3‚3′‚4‚4′‐biphenyltetracarboxylic dianhydride via a two‐step method. The as‐synthesized PI not only showed high thermal stability and excellent mechanical properties, but also possessed high dielectric constant (7.1, 100 Hz) and low dielectric loss (below 0.04) in a wide frequency range from 100 Hz to 105 Hz. The obtained PI promises potential applications in electronic products. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40828.
Nonisothermal crystallization kinetics of poly(butylene terephthalate)/multiwalled carbon nanotubes nanocomposites prepared by in situ polymerization
Authors: Fang Hui , Wu Fangjuan 
Published: April 2014

ABSTRACTPoly(butylene terephthalate)/multiwalled carbon nanotubes (PBT/MWNT) nanocomposites were prepared by in situ ring‐opening polymerization of cyclic butylene terephthalate oligomers (CBT). The nonisothermal crystallization behavior of the neat PBT and the PBT/MWNT nanocomposites was analyzed quantitatively. The results reveal that the combined Avrami/Ozawa equation exhibits great advantages in describing the nonisothermal crystallization of PBT and its nanocomposites. The presence of MWNTs has the nucleation effect promoting crystallization rate for the nanocomposites, and the maximum one is observed in the nanocomposite having 0.75 wt % MWNT content. On the other hand, the addition of MWNTs has the impeding effect reducing the chain mobility and retarding crystallization, which is confirmed by the crystallization activation energies. However, the nucleation effect of MWNTs plays the dominant role in the crystallization of PBT/MWNT nanocomposites, in other words, the incorporation of MWNTs is increasing the crystallization rate of the nanocomposites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40849.
Incidental catch of marine turtles by Spanish bottom trawlers in the western Mediterranean
Authors: Domènech Francesc , Álvarez de Quevedo Irene , Merchán Manuel , Revuelta Ohiana , Vélez‐Rubio Gabriela , Bitón Sebastián , Cardona Luis , Tomás Jesús 
Published: April 2014

Abstract

A questionnaire‐based survey of fishermen was conducted in the Valencia region (eastern Spain) to assess the levels of marine turtle bycatch. Interviews covered 41.3% of the bottom trawling fleet in the region and included 111 fishermen (one per boat). Results were combined with those from previous studies conducted in neighbouring regions using the same methodology to assess the global impact of bottom trawling on the western Mediterranean stock of the loggerhead turtle (Caretta caretta).
Estimated turtle catch per unit effort (CPUE) is 0.09 turtles per vessel per month, according to the information reported by fishermen. As a consequence, the whole fleet of bottom trawlers operating off the Valencia region was involved annually in 238 turtle bycatch events (95%, CI: 173–304).
Ivlev's electivity index revealed that bottom trawling bycatch was higher than expected according to fishing effort in the northern part of the study area, where the continental shelf widens.
The fishermen's perception was that the local stock of loggerhead turtles is declining, and that drifting longlines and bottom trawling are, at least in part, responsible for this trend.
According to previous studies as well as the current results, bottom trawlers operating off mainland Spain capture mainly loggerhead turtles from the rookeries in the eastern Mediterranean, with only a low percentage of turtles of Atlantic origin.
Loggerhead turtle bycatch by bottom trawling deserves more attention in the Valencia region, particularly in its northern part. Conservation measures in the area are discussed.
Copyright © 2014 John Wiley & Sons, Ltd.