bluuebunny/crossref_metadata_2025_split huggingface dataset:
How winner cells cause the demise of loser cells
Authors: Lolo Fidel‐Nicolás , Tintó Sergio Casas , Moreno Eduardo 
Published: February 2013

AbstractRecent results show that, during the process known as cell competition, winner cells identify and kill viable cells from a growing population without requiring engulfment. The engulfment machinery is mainly required in circulating macrophages (hemocytes) after the discrimination between winners and losers is completed and the losers have been killed and extruded from the epithelium. Those new results leave us with the question as to which molecules allow winner cells to recognize and impose cell death on the loser cells during cell competition.
Biochemical characterization of an alcohol dehydrogenase from Ralstonia sp.
Authors: Kulig Justyna , Frese Amina , Kroutil Wolfgang , Pohl Martina , Rother Dörte 
Published: February 2013

AbstractStereoselective reduction towards pharmaceutically potent products with multi‐chiral centers is an ongoing hot topic, but up to now catalysts for reductions of bulky aromatic substrates are rare. The NADPH‐dependent alcohol dehydrogenase from Ralstonia sp. (RADH) is an exception as it prefers sterically demanding substrates. Recent studies with this enzyme indicated outstanding potential for the reduction of various alpha‐hydroxy ketones, but were performed with crude cell extract, which hampered its detailed characterization. We have established a procedure for the purification and storage of RADH and found a significantly stabilizing effect by addition of CaCl2. Detailed analysis of the pH‐dependent activity and stability yielded a broad pH‐optimum (pH 6–9.5) for the reduction reaction and a sharp optimum of pH 10–11.5 for the oxidation reaction. The enzyme exhibits highest stability at pH 5.5–8 and 8–15°C; nevertheless, biotransformations can also be carried out at 25°C (half‐life 80 h). Under optimized reaction parameters a thorough study of the substrate range of RADH including the reduction of different aldehydes and ketones and the oxidation of a broad range of alcohols was conducted. In contrast to most other known alcohol dehydrogenases, RADH clearly prefers aromatic and cyclic aliphatic compounds, which makes this enzyme unique for conversion of space demanding substrates. Further, reductions are catalyzed with extremely high stereoselectivity (>99% enantio‐ and diastereomeric excess). In order to identify appropriate substrate and cofactor concentrations for biotransformations, kinetic parameters were determined for NADP(H) and selected substrates. Among these, we studied the reduction of both enantiomers of 2‐hydroxypropiophenone in more detail. Biotechnol. Bioeng. 2013; 110: 1838–1848. © 2013 Wiley Periodicals, Inc.
Wettstreit um die Polyamidfasern
Authors: Vogler Herbert 
Published: February 2013

AbstractBeginnend in den 1930er Jahren wurde die Textilwelt durch die Erfindung der synthetischen Fasern nachhaltig verändert. Nicht nur das Angebot an textilen Rohstoffen wurde ausgeweitet, sondern mit Hilfe der neuen Fasern entstanden Textilartikel mit bis dahin nicht bekannten Eigenschaften. Ein Blick zurück anlässlich 75 Jahre Polyamidfaser Perlon.
Climate change impacts on potential recruitment in an ecosystem engineer
Authors: Morgan Emer , O' Riordan Ruth M. , Culloty Sarah C. 
Published: February 2013

AbstractClimate variability and the rapid warming of seas undoubtedly have huge ramifications for biological processes such as reproduction. As such, gametogenesis and spawning were investigated at two sites over 200 km apart on the south coast of Ireland in an ecosystem engineer, the common cockle, Cerastoderma edule. Both sites are classed as Special Areas of Conservation (SACs), but are of different water quality. Cerastoderma edule plays a significant biological role by recycling nutrients and affecting sediment structure, with impacts upon assemblage biomass and functional diversity. It plays a key role in food webs, being a common foodstuff for a number of marine birds including the oystercatcher. Both before and during the study (early 2010–mid 2011), Ireland experienced its two coldest winters for 50 years. As the research demonstrated only slight variation in the spawning period between sites, despite site differences in water and environmental quality, temperature and variable climatic conditions were the dominant factor controlling gametogenesis. The most significant finding was that the spawning period in the cockle extended over a greater number of months compared with previous studies and that gametogenesis commenced over winter rather than in spring. Extremely cold winters may impact on the cockle by accelerating and extending the onset and development of gametogenesis. Whether this impact is positive or negative would depend on the associated events occurring on which the cockle depends, that is, presence of primary producers and spring blooms, which would facilitate conversion of this extended gametogenesis into successful recruitment.
Genetic structure of introduced populations: 120‐year‐old DNA footprint of historic introduction in an insular small mammal population
Authors: Simpson Siobhan , Blampied Nick , Peniche Gabriela , Dozières Anne , Blackett Tiffany , Coleman Stephen , Cornish Nina , Groombridge Jim J. 
Published: February 2013

AbstractWildlife populations have been introduced to new areas by people for centuries, but this human‐mediated movement can disrupt natural patterns of genetic structure by altering patterns of gene flow. Insular populations are particularly prone to these influences due to limited opportunities for natural dispersal onto islands. Consequently, understanding how genetic patterns develop in island populations is important, particularly given that islands are frequently havens for protected wildlife. We examined the evolutionary origins and extent of genetic structure within the introduced island population of red squirrels (Sciurus vulgaris) on the Channel Island of Jersey using mitochondrial DNA (mtDNA) control region sequence and nuclear microsatellite genotypes. Our findings reveal two different genetic origins and a genetic architecture reflective of the introductions 120 years ago. Genetic structure is marked within the maternally inherited mtDNA, indicating slow dispersal of female squirrels. However, nuclear markers detected only weak genetic structure, indicating substantially greater male dispersal. Data from both mitochondrial and nuclear markers support historic records that squirrels from England were introduced to the west of the island and those from mainland Europe to the east. Although some level of dispersal and introgression across the island between the two introductions is evident, there has not yet been sufficient gene flow to erase this historic genetic “footprint.” We also investigated if inbreeding has contributed to high observed levels of disease, but found no association. Genetic footprints of introductions can persist for considerable periods of time and beyond traditional timeframes of wildlife management.
Copper(II) Complexes with Schiff Bases Containing a Disiloxane Unit: Synthesis, Structure, Bonding Features and Catalytic Activity for Aerobic Oxidation of Benzyl Alcohol
Authors: Soroceanu Alina , Cazacu Maria , Shova Sergiu , Turta Constantin , Kožíšek Jozef , Gall Marian , Breza Martin , Rapta Peter , Mac Leod Tatiana C. O. , Pombeiro Armando J. L. , Telser Joshua , Dobrov Anatolie A. , Arion Vladimir B. 
Published: February 2013

AbstractMononuclear copper(II) salen‐type Schiff base complexes, CuIIL1–5[H2L1to H2L5= tetradentateN,N,O,Oligands derived from 2‐hydroxybenzaldehyde, 2,4‐dihydroxybenzaldehyde, 3,5‐dibromo‐2‐hydroxybenzaldehyde, 2‐hydroxy‐5‐nitrobenzaldehyde, 5‐chloro‐2‐hydroxybenzaldehyde and 1,3‐bis(3‐aminopropyl)tetramethyldisiloxane, respectively] were prepared in situ in the presence of a copper(II) salt or by direct complexation between a copper(II) salt and a presynthesised Schiff base. The compounds {CuL1, CuL1·0.5Py, CuL2·0.375CH2Cl2, (CuL3)[Cu(4‐Me‐Py)4Cl]Cl·2H2O, CuL4, CuL4·CHCl3and CuL5, as well as the isolated ligand H2L3} were characterised by elemental analysis, spectroscopic methods (IR, UV/Vis,1H NMR, EPR) and X‐ray crystallography. The formation of a 12‐membered central chelate ring in these complexes is effected by the tetramethyldisiloxane unit, which separates the aliphatic chains, thus significantly reducing the mechanical strain in such a chelate ring. We dub this a “shoulder yoke effect” by analogy with the load‐spreading ability of such an ancient device. The coordination geometry of copper(II) in CuIIL1–5can be described as tetrahedrally distorted square‐planar. Maximum tetrahedral distortion of the coordination geometry expressed by the parameterτ4was observed for CuL1(0.460), while distortion was minimal for the two crystallographically independent molecules of CuL2(0.219 and 0.284). The Si–O–Si bond angle varies markedly between 169.75(2)° for CuL1and 154.2(3)° for CuL4·CHCl3. Charge‐density and DFT calculations on CuL1indicate high ionic character of the Si–O bonds in the tetramethyldisiloxane fragment. The new copper(II) complexes bearing the disiloxane moiety have been shown to act as catalyst precursors for the aerobic oxidation of benzyl alcohol to benzaldehyde mediated by the TEMPO radical, reaching yields and TONs up to 99 % and 990, respectively, under mild and environmentally friendly conditions (50 °C; MeCN/H2O, 1:1).
Imido‐Supported Borohydrides of Titanium, Vanadium and Molybdenum
Authors: Khalimon Andrey Y. , Peterson Erik , Lorber Christian , Kuzmina Lyudmila G. , Howard Judith A. K. , van der Est Art , Nikonov Georgii I. 
Published: February 2013

AbstractNew imido bis(borohydride) complexes [(RN=)M(PMe3)2(η2‐BH4)2] [R = Ar, M = Ti (3); R = Ar, M = V (5); R = Ar, M = Mo (6); R = Ar′, M = Mo (7); Ar = 2,6‐iPr2C6H3, Ar′ = 2,6‐Me2C6H3] were prepared by the reaction of dichlorides [(RN=)MCl2(PMe3)n] (M = Ti, n = 2; M = V, n = 2, M = Mo, n = 3) with LiBH4 (2 equiv) in THF. Compounds 3, 5, 6 and 7 were studied by IR spectroscopy and X‐ray diffraction, and an EPR spectroscopy study was performed for paramagnetic compound 5. In 3, the two borohydride units are orthogonal to each other as a result of the overlap of an antiphase combination of B–H orbitals with the empty dxy orbital of Ti. In contrast, the dxy orbital of the metal atom is singly occupied in 5 and fully occupied in 6 and 7, and both borohydride ligands are oriented in the same way, with the B(μ‐H2)M moieties orthogonal to the P–M–P vector.
Three Polymeric Polyoxometalate Compounds Based on Twisted Poly‐Keggin Chains
Authors: Ren Yuan‐hang , Hu Yi‐chen , Kong Zu‐ping , Gu Min , Yue Bin , He He‐yong 
Published: February 2013

AbstractThree polymeric polyoxometalate (POM) compounds, [PMoVI10MoV2O39](C2N4H4)2[(CH3)4N]3·H2O (1), [PW11CuO39]2·[Cu(en)2H2O]4·[(CH3)4N]2·6H2O (en = ethenediamine) (2), and [SiW11CuO39]2·[Cu(en)2]4·[Cu(en)2H2O]2·10H2O (3) were isolated under hydrothermal conditions. Compound 1 contains one‐dimensional twisted poly‐Keggin chains that consist of two‐electron‐reduced Keggin units through MoV–Ot–MoV bridges. Compounds 2 and 3 contain one‐dimensional twisted poly‐Keggin chains that consist of Cu‐monosubstituted Keggin units through W–Ot–Cu bridges. Twisted chains are formed due to the different orientations of the Keggin units during polymerization. The compounds were characterized by single‐crystal X‐ray diffraction, elemental analysis, IR, X‐ray photoelectron spectroscopy (XPS), thermogravimetry (TG), and cyclic voltammetry. The driving force for polymerization by the sharing of a terminal oxygen atom per POM unit likely arises from the existence of a low‐valence metal (MoV or CuII), which reduces the charge density of each POM unit.
Hydrogen Peroxide Activation over TiIV: What Have We Learned from Studies on Ti‐Containing Polyoxometalates?
Authors: Kholdeeva Oxana A. 
Published: February 2013

AbstractThis short review paper summarizes recent findings in the field of H2O2 activation over TiIV centers on the basis of model studies of Ti‐containing polyoxometalates (Ti‐POM) that used both experimental and computational techniques. Alkene epoxidation with H2O2 mediated by two different POMs, the Ti‐monosubstituted Keggin‐type POM, [PTi(OH)W11O39]4– (1), and the Ti‐disubstituted sandwich‐type POM, [Ti2(OH)2As2W19O67(H2O)]8– (2), which contain well‐defined six‐ and five‐coordinate titanium atoms, respectively, as well as some other Ti‐POMs, has been explored to elucidate the role of the TiIV coordination environment in this reaction. The effect of the Ti‐POM protonation state on the mechanism of H2O2 activation has been analyzed in the context of its relevance to alkene epoxidation. The crucial factors that favor the heterolytic oxidation mechanism that leads to the selective formation of epoxides have been disclosed.
Effectiveness of modified zeolites as adsorbent materials for frying oils
Authors: Dülger Alper , Yılmaz Emin 
Published: February 2013

AbstractNatural zeolite was modified by four different techniques namely using Tween80, β‐cyclodextrine and olive mill waste water at RT and hydrochloric acid at 110°C, and then modified zeolites were used as adsorbent materials in six consecutive days dough frying with refined hazelnut oil. Some parameters in the oil samples of control and experimental groups were measured and the ranges were determined as following; total polar materials (TPM)‐chromatography (4.09–70.22%), free acidity (0.16–1.19%), smoke point (221.50–184.00°C), conjugated dienoic acids (0.36–2.19%), L value (35.65–52.15), a* value (−0.18–5.98), b* value (−3.73–10.40), turbidity (0.70–10.40 NTU), viscosity (67.67–825.50 cP), and oil absorbed by the dough (5.10–8.85%). The results of this study have shown that both natural zeolite and modified zeolites have different level of activities as frying oil adsorbent materials. The best results were achieved with Tween80 modified zeolite for the TPMs, free acidity, instrumental color values, smoke point, and conjugated dienoic acid measurements. Similarly better result for turbidity was with olive mill waste water modified zeolite and for viscosity was with hydrochloric acid modified zeolite. It was determined that adsorbent treatment did not affect fat absorption level of fried dough.Practical applications: The results of this study have shown that natural zeolite modification with different techniques can improve its adsorption capacity significantly. In this respect, utilization of modified zeolite for frying oil recovery applications can be an industrially sound practice since natural zeolite is a very cheap and easily found material.
Association of Thymbra capitata essential oil and chitosan (TCCH hydrogel): a putative therapeutic tool for the treatment of vulvovaginal candidosis
Authors: de‐Oliveira A. Palmeira‐ , de‐Oliveira R. Palmeira‐ , Gaspar C. , Salgueiro L. , Cavaleiro C. , de‐Oliveira J. Martinez‐ , Queiroz J.A. , Rodrigues A.G. 
Published: February 2013

ABSTRACTIn this study we tested the anti‐Candida effect of Thymbra capitata essential oil (EO) plus chitosan and developed a new therapeutic tool. The classical check‐board methodology was used to determine the anti‐Candida activity that results from product association. The incorporation of T. capitata EO in a chitosan hydrogel, using lactic acid as the solvent, resulted in the TCCH hydrogel. Its anti‐Candida activity was studied by using 18 Candida strains, according to the CLSI M27‐A3 micromethod and the lethal effect according to the protocol proposed by Canton et al. The TCCH activity in acidic conditions corresponding to a healthy vaginal pH (4.5) was also tested. Its anti‐Candida activity upon pre‐formed biofilm metabolism and biomass was tested using the semi‐quantitative XTT reduction assay and the crystal violet staining assay, respectively. The hydrogel interaction with the yeast surface was shown by confocal microscopy. TCCH hydrogel presented an acidic nature, compatible with the vaginal pH. The association of both natural products revealed an additive effect upon Candida and TCCH hydrogel showed to be active upon both Candida planktonic and biofilms. No cell invasion was observed. Being a new product with an acidic nature compatible with the vaginal environment and presenting a potent effect upon Candida planktonic and biofilm cells, TCCH hydrogel could represent a valuable tool for the treatment of vulvovaginal candidosis. Copyright © 2013 John Wiley & Sons, Ltd.
A hybrid DSMC/Navier–Stokes frame to solve mixed rarefied/nonrarefied hypersonic flows over nano‐plate and micro‐cylinder
Authors: Darbandi Masoud , Roohi Ehsan 
Published: February 2013

SUMMARYWe extend a hybrid DSMC/Navier–Stokes (NS) approach to unify the DSMC and the NS simulators in one framework capable of solving the mixed non‐equilibrium and near‐equilibrium flow regions efficiently. Furthermore, we use a one‐way state‐based coupling (Dirichlet–Dirichlet boundary‐condition coupling) to transfer the required information from the continuum region to the rarefied one. The current hybrid DSMC–NS frame is applied to the hypersonic flows over nanoflat plate and microcylinder cases. The achieved solutions are compared with the pure DSMC and NS solutions. The results show that the current hybrid approach predicts the surface heat transfer rate and shear stress magnitudes very accurately. Some important conclusions can be drawn from this study. For example, although the shock wave region would be a non‐equilibrium region, it is not necessary to use a pure DSMC simulator to solve it entirely. This is important when the researchers wish to predict the surface properties such as velocity slip, temperature jump, wall heat flux rate, and friction drag magnitudes accurately. Our investigation showed that our hybrid solution time would be at least 40% (for the flat plate) and 35% (for the cylinder) of the time that must be spent by a pure DSMC solver to attain the same accuracy.Copyright © 2013 John Wiley & Sons, Ltd.
Superficial musculoaponeurotic system flap in partial parotidectomy and clinical and subclinical Frey's syndrome. Cosmesis and quality of life
Authors: Barberá Rafael , Castillo Felipe , D'Oleo Claudio , Benítez Susana , Cobeta Ignacio 
Published: February 2013

BackgroundFrey's syndrome (FS), facial depression, and noticeable scar may have an impact on patient's quality of life after a parotidectomy. The superficial musculoaponeurotic system (SMAS) flap has been used to ameliorate those effects.MethodsForty‐seven consecutive parotidectomies were analyzed; SMAS flap was performed in 26 of them. We investigated clinical FS, subclinical FS, and cosmetic satisfaction, and compared SMAS flap versus cases where this was not done.ResultsBy performing the SMAS flap, the occurrence of clinical FS was reduced; however, there was no significant difference. Nonetheless, there was a significant difference in the perspiration intensity in favor of the group with SMAS flaps. In the cases we studied, the cosmetic satisfaction was high, even though facial contour‐filling techniques were not used.ConclusionsProvided that the intensity of sweating is the main factor affecting the quality of life after surgery in patients, performing a SMAS flap renders the intervention worthwhile. © 2013 Wiley Periodicals, Inc. Head Neck 36: 130–136, 2014
Cellular and animal models for mitochondrial complex I deficiency: A focus on the NDUFS4 subunit
Authors: Breuer Megan E. , Willems Peter H.G.M. , Smeitink Jan A.M. , Koopman Werner J.H. , Nooteboom Marco 
Published: February 2013

AbstractTo allow the rational design of effective treatment strategies for human mitochondrial disorders, a proper understanding of their biochemical and pathophysiological aspects is required. The development and evaluation of these strategies require suitable model systems. In humans, inherited complex I (CI) deficiency is one of the most common deficiencies of the mitochondrial oxidative phosphorylation system. During the last decade, various cellular and animal models of CI deficiency have been presented involving mutations and/or deletion of the Ndufs4 gene, which encodes the NDUFS4 subunit of CI. In this review, we discuss these models and their validity for studying human CI deficiency. © 2013 IUBMB Life, 65(3):202–208, 2013
Microscopy of single FoF1‐ATP synthases— The unraveling of motors, gears, and controls
Authors: Börsch Michael 
Published: February 2013

AbstractOptical microscopy of single F1‐ATPase and FoF1‐ATP synthases started 15 years ago. Direct demonstration of ATP‐driven subunit rotation by videomicroscopy became the new exciting tool to analyze the conformational changes of this enzyme during catalysis. Stimulated by these experiments, technical improvements for higher time resolution, better angular resolution, and reduced viscous drag were developed rapidly. Optics and single‐molecule enzymology were entangled to benefit both biochemists and microscopists. Today, several single‐molecule microscopy methods are established including controls for the precise nanomanipulation of individual enzymes in vitro. Förster resonance energy transfer, which has been used for simultaneous monitoring of conformational changes of different parts of this rotary motor, is one of them and may become the tool for the analysis of single FoF1‐ATP synthases in membranes of living cells. Here, breakthrough experiments are critically reviewed and challenges are discussed for the future microscopy of single ATP synthesizing enzymes at work. © 2013 IUBMB Life, 65(3):227–237, 2013
The More the Merrier? Working Towards Multidisciplinary Management of Obstructive Sleep Apnea and Comorbid Insomnia
Authors: Ong Jason C. , Crisostomo M. Isabel 
Published: February 2013

ObjectivesThe goal of this article was to provide an overview of the diagnostic considerations, clinical features, pathophysiology, and treatment approaches for patients with obstructive sleep apnea (OSA) and comorbid insomnia.MethodWe begin with a review of the literature on OSA and comorbid insomnia. We then present a multidisciplinary approach using pulmonary and behavioral sleep medicine treatments.ResultsOSA and insomnia co‐occur at a high rate and such patients have distinct clinical features. Empirically supported treatments are available for OSA and insomnia independently but there are no standards or guidelines for how to implement these treatments for patients who suffer from both disorders.ConclusionsMultidisciplinary treatment holds promise for patients with comorbid sleep disorders. Further research should be aimed at optimizing treatments and developing standards of practice for this population.
Changes in Early Maladaptive Schemas After Residential Treatment for Substance Use
Authors: Shorey Ryan C. , Stuart Gregory L. , Anderson Scott , Strong David R. 
Published: February 2013

ObjectivesEarly maladaptive schemas are cognitive and behavioral patterns that cause considerable distress and are theorized to underlie mental health problems. Research suggests that early maladaptive schemas may underlie substance abuse and that the intensity of early maladaptive schemas may decrease after brief periods of abstinence. The current study examined changes in early maladaptive schemas after a 4‐week residential substance use treatment program.MethodPreexisting records of a sample of male alcohol‐ and opioid‐dependent treatment seeking adults (N = 97; mean age = 42.55) were reviewed for the current study.ResultsPre‐post analyses demonstrated that 8 of the early maladaptive schemas significantly decreased by the end of the 4‐week treatment.ConclusionsFindings indicate that early maladaptive schemas can be modified during brief substance use treatment and may be an important component of substance use intervention programs. Implications of these findings for substance use treatment are discussed.