bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structures of domains I and IV from YbbR are representative of a widely distributed protein family
Authors: Barb Adam W. , Cort John R. , Seetharaman Jayaraman , Lew Scott , Lee Hsiau‐Wei , Acton Thomas , Xiao Rong , Kennedy Michael A. , Tong Liang , Montelione Gaetano T. , Prestegard James H. 
Published: December 2010

AbstractYbbR domains are widespread throughout Eubacteria and are expressed as monomeric units, linked in tandem repeats or cotranslated with other domains. Although the precise role of these domains remains undefined, the location of the multiple YbbR domain‐encoding ybbR gene in the Bacillus subtilis glmM operon and its previous identification as a substrate for a surfactin‐type phosphopantetheinyl transferase suggests a role in cell growth, division, and virulence. To further characterize the YbbR domains, structures of two of the four domains (I and IV) from the YbbR‐like protein of Desulfitobacterium hafniense Y51 were solved by solution nuclear magnetic resonance and X‐ray crystallography. The structures show the domains to have nearly identical topologies despite a low amino acid identity (23%). The topology is dominated by β‐strands, roughly following a “figure 8” pattern with some strands coiling around the domain perimeter and others crossing the center. A similar topology is found in the C‐terminal domain of two stress‐responsive bacterial ribosomal proteins, TL5 and L25. Based on these models, a structurally guided amino acid alignment identifies features of the YbbR domains that are not evident from naïve amino acid sequence alignments. A structurally conserved cis‐proline (cis‐Pro) residue was identified in both domains, though the local structure in the immediate vicinities surrounding this residue differed between the two models. The conservation and location of this cis‐Pro, plus anchoring Val residues, suggest this motif may be significant to protein function.
A new approach for structure analysis of two‐dimensional membrane protein crystals using X‐ray powder diffraction data
Authors: Dilanian R. A. , Darmanin C. , Varghese J. N. , Wilkins S. W. , Oka T. , Yagi N. , Quiney H. M. , Nugent K. A. 
Published: December 2010

AbstractThe application of powder diffraction methods to problems in structural biology is generally regarded as intractable because of the large number of unresolved, overlapping X‐ray reflections. Here, we use information about unit cell lattice parameters, space group transformations, and chemical composition as a priori information in a bootstrap process that resolves the ambiguities associated with overlapping reflections. The measured ratios of reflections that can be resolved experimentally are used to refine the position, the shape, and the orientation of low‐resolution molecular structures within the unit cell, in leading to the resolution of the overlapping reflections. The molecular model is then made progressively more sophisticated as additional diffraction information is included in the analysis. We apply our method to the recovery of the structure of the bacteriorhodopsin molecule (bR) to a resolution of 7 Å using experimental data obtained from two‐dimensional purple membrane crystals. The approach can be used to determine the structure factors directly or to provide reliable low‐resolution phase information that can be refined further by the conventional methods of protein crystallography.
Ultrafast excited state dynamics of monomeric bacteriochlorophyll a
Authors: Kosumi Daisuke , Maruta Satoshi , Fujii Ritsuko , Kanemoto Katsuichi , Sugisaki Mitsuru , Hashimoto Hideki 
Published: December 2010

AbstractUltrafast excited state dynamics of the photosynthetic pigment bacteriochlorophyll a in solution have been investigated by means of steady‐state and time‐resolved spectroscopic techniques. Photo‐induced absorption spectra were observed upon excitation of bacteriochlorophyll a into its Qy or Qx absorption band. We show an incorporation of the Qx state in the ultrafast excited state dynamics of Bchl a in solution based on a comparison of transient absorption, beaching, and stimulated emission kinetics after excitation to the Qx or Qy band. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rabi splitting in CuCl microcavity with DBR consisting of PbCl2/NaF multilayers
Authors: Yoshino S. , Oohata G. , Shim Y. , Ishihara H. , Mizoguchi K. 
Published: December 2010

AbstractWe have investigated exciton‐photon coupling phenomena in bulk CuCl microcavities with distributed Bragg reflectors consisting of PbCl2 and NaF multilayers. The CuCl microcavities, which have the cavity‐length of half‐integer multiples of Z3 exciton wavelength, were fabricated by the vacuum deposition in the consistent process. From angle‐resolved reflectance spectra, the cavity polaritons originating from Z3, Z1,2 excitons and cavity photon were clearly obtained in each sample. We assumed the three polariton modes derived from 3×3 phenomenological Hamiltonian with two vacuum Rabi splitting energies. From the analysis, the obtained Rabi splitting energies for λ‐cavity are 110 and 195 meV for Z3 and Z1,2 excitons, respectively. On the other hand, we have determined the complex refractive indices of PbCl2/NaF layers by spectral ellipsometry. Using these optical constants, the reflectance spectrum of the sample was calculated by nonlocal theory with spatial structures of wavefunction of excitons. The spectrum and Rabi splitting energies estimated by the calculations agree well with the experimental results (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exciton emission in tetrahedral carbon self‐organized and ring‐shaped quantum dots
Authors: Mashchenko V. E. , Puzikov V. M. , Semenov A. V. , Yaminsky I. V. 
Published: December 2010

AbstractAFM topography, TEM data, spectra of radiative annihilation of excitons in tetrahedral nano carbon quantum dots (QDs) and quantum rings (QRs) were studied in detail. Anti‐Stokes exciton emission (ASEE) spectra in 6.3–4.7 eV energy interval at 4.2–200 K were induced via cascade Urbach tail states transitions under femtosecond laser radiation (λ=266 nm) pumping. Near diamond in composition nano carbon layers (nt‐C) on cleaved KCl and polished Si substrates with high density of self‐organized surface QDs, isolated, aggregated QRs and fractal bulk networks were grown using carbon ion beam of low energy and fluence. Regular networks of QDs 3–20 nm in diameter less than 1 nm in height and up to 3×1011 cm‐2density were obtained. In ASEE spectra fine–structured via 5–6 meV narrow and week 6.0596 eV, 6.0557 eV and 6.0032 eV lines have been resolved at low level of excitation.The strong, fine‐structured via 3.0–4.5 meV lines and bands above and below the energy of indirect exciton transition in diamond have been found in two types of nt‐C layers as well. The parameter dependences of lines and bands upon the level of laser pumping were studied. We suppose that above mentioned components of ASEE spectra are originated from radiative annihilation of excitons in surface and bulk QDs and ring‐like quantum networks. At strong excitation level fine‐structured with 3.5–4.0 meV energy period new 4.8394 eV and 4.7925 eV exciton lines were induced and dominated in emission spectra. These lines are result of exciton annihilation in bulk quantum confined fractal features. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Factors structuring macroinvertebrate communities in a headwater stream and its springs in the Upper Austrian Limestone Alps
Authors: Pokorny Nella , Fesl Christian , Schagerl Michael , Waringer Johann 
Published: December 2010

ABSTRACTThe Almbach, a headwater stream in the Upper Austrian foothills of the Alps bordered by mountain pastures was studied to gain insight into the benthic macroinvertebrate community and its habitat. Two springs, one of them fenced in to prevent livestock access, and two more sites of the headwater section were investigated. A discriminant analysis (DA) based on hydrochemistry and phytobenthos revealed three functions with 86% of all samples correctly classified to the four sites. The first function clearly separated the two springs with phosphorus and oxygen as the most important discriminating factors. Spring sites and headwater sites were split up by the second function mainly due to nitrate concentration, but no differences could be detected for the two stream sites. With the exception of the fenced spring, indicator taxa could be assigned to all sites by means of an Indicator Species Analysis (ISA). Polyvalent taxa groups such as Gastropoda and Ostracoda were indicators for the unfenced spring site. This is in accordance to observed low abundances of sensitive plecopteran taxa and suggests a negative impact of livestock trampling on the invertebrate community. Redundancy Analysis explained 99% of the macroinvertebrate‐environment relation. The first axis separated springs from stream sites and was correlated with nitrate, pH, water temperature and phytobenthos eveness. Phosphorus was responsible for splitting the unfenced spring and the downstream station from the fenced spring and the upstream location along the second axis. Ephemeropteran taxa likeHabrophlebiasp. were related to elevated pH, increased water temperature and low nitrate concentrations. In accordance to the ISA, nitrate played an important role for tolerant Gastropoda and Ostracoda at the unfenced spring. Copyright © 2010 John Wiley & Sons, Ltd.
Ecologically sustainable economic development in aquatic ecosystems: from theory to environmental policy
Authors: Mavromati Georgia , Bithas Kostas 
Published: December 2010

ABSTRACTEcologically sustainable economic development (ESED) is considered to be a priority axis for policies designed for the preservation of ecosystems. In this context, the ESED concept has been operationally defined through several distinct approaches. Nevertheless, no consensus has been reached between and among approaches as to an operational interpretation and practical application of ESED. The present paper examines and evaluates the operational appeal of certain ESED approaches within the current policy framework regarding aquatic ecosystems. To this purpose, the paper investigates the relationship between representative approaches to ESED and the current policies for aquatic ecosystems in the European Union and the United States of America. These relatively mature policies offer operational grounds on which the operational dimensions of ESED approaches may be evaluated. Analysis focuses on the crucial question of to what extent the current major policies for aquatic ecosystems reflect the rationale and conditions of the prevailing ESED scientific approaches. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Fabrication of the smallest organic nanocolloids by a top‐down method based on laser ablation
Authors: Sugiyama Teruki , Asahi Tsuyoshi 
Published: December 2010

AbstractStable aqueous colloids of 10‐nm sized organic nanoparticles were tailored by laser ablation of microcrystalline quinacridone in water. The nanocolloids were flaky in shape and had the dimension of a width of 13 (±5) nm and a height of 1.4 (±0.5) nm. The formation mechanism is discussed in terms of laser‐induced fragmentation of organic solids and the potential application of aqueous organic nanocolloids free from any additives and chemicals is considered.
Antiapoptotic efficacy of folic acid and vitamin B12 against arsenic‐induced toxicity
Authors: Majumdar Sangita , Maiti Anasuya , Karmakar Subhra , Sekhar Das Asankur , Mukherjee Sandip , Das Dolan , Mitra Chandan 
Published: December 2010

AbstractEarlier, we proposed that the ability of folic acid and vitamin B12 to preserve systemic and mitochondrial function after short‐term exposure to arsenic may prevent further progression to more permanent injury and pathological changes leading to cell death. To elucidate its mechanism, the present study examined the antiapoptotic efficacy of folic acid and vitamin B12 against short‐term arsenic exposure‐induced hepatic mitochondria oxidative stress and dysfunction. Sixteen to eighteen weeks old male albino rats weighing 140–150 × g were divided into five groups: Control (A), Arsenic‐treated (B), Arsenic + folic acid (C), Arsenic +vitamin B12 (D), and Arsenic + folic acid + vitamin B12 (E). Data generated indicated that folic acid and vitamin B12 separately or in combination can give significant protection against alterations in oxidative stress and apoptotic marker parameters and downstream changes in mitochondria, namely pro‐oxidative (NO, TBARS, OH−) and antioxidative defense (SOD, CAT, GSH) markers, iNOS protein expression, mitochondrial swelling, cytochrome c oxidase and Ca2+‐ATPase activity, Ca2+ content, caspase‐3 activity. Additionally, results of hepatic cell DNA fragmentation, arsenic load of blood, hepatic tissue and urine, and histological observations, all strongly support that both these supplements have efficacy in preventing apoptotic changes and cellular damage. As the mechanisms of actions of both of these supplements are methylation related, a combined application was more effective. Results further reveal new molecular targets through which folic acid and vitamin B12 separately or in combination work to alleviate one critical component of arsenic‐induced liver injury: mitochondria dysfunction. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
Biochemical and genotoxic effect of triclosan on earthworms (Eisenia fetida) using contact and soil tests
Authors: Lin Dasong , Xie Xiujie , Zhou Qixing , Liu Yao 
Published: December 2010

AbstractTriclosan (TCS) is a broad‐spectrum bactericide that is used for a variety of antimicrobial functions. TCS is frequently detected in the terrestrial environment due to application of sewage sludge to agricultural land. In the present study, 48‐h paper contact and 28‐day spiked soil tests were conducted to examine the toxic effects of TCS on the antioxidative and genetic indices of earthworms (Eisenia fetida). The activity of antioxidative enzymes (superoxide dismutase, SOD; catalase, CAT) and the content of the lipid peroxidation product (malondialdehyde, MDA) were determined as biomarkers of oxidative stress in E. fetida. Moreover, single cell gel electrophoresis (SCGE) was used as a biomarker of genotoxicity. The results showed that triclosan induced a significant increase (P < 0.05) in antioxidative enzyme activities and MDA content. Of all of the biomarkers examined, CAT activity was most sensitive to TCS, and the CAT activity increased significantly (P < 0.05) at bactericidal concentrations of 7.86 ng cm−2 in the contact test and 10 mg kg−1 in the spiked soil test. The comet assay showed that TCS treatments significantly induced (P < 0.05) DNA damage in E. fetida, and that 78.6 ng cm−2 caused significant genotoxic effects in the acute test (48 h). Clear dose‐dependent DNA damage to E. fetida was observed both in contact and spiked soil tests. These results imply that TCS may have potential biochemical and genetic toxicity toward earthworms (E. fetida). A battery of biomarkers covering multiple molecular targets of acute toxicity can be combined to better understand the impacts of TCS on E. fetida. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012.
ASYMPTOTIC INTEGRATION OF SECOND-ORDER NONLINEAR DIFFERENCE EQUATIONS
Authors: EHRNSTRÖM MATS , TISDELL CHRISTOPHER C. , WAHLÉN ERIK 
Published: December 2010

AbstractIn this work we analyse a nonlinear, second-order difference equation on an unbounded interval. We present new conditions under which the problem admits a unique solution that is of a particular linear asymptotic form. The results concern the general behaviour of solutions to the initial-value problem, as well as solutions with a given asymptote. Our methods involve establishing suitable complete metric spaces and an application of Banach's fixed-point theorem. For the solutions found in our two main theorems—fixed initial data and fixed asymptote, respectively—we establish exact convergence rates to solutions of the differential equation related to our difference equation. It turns out that for the asymptotic case there is uniform convergence for both the solution and its derivative, while in the other case the convergence is somewhat weaker. Two different techniques are utilized, and for each one has to employ ad-hoc methods for the unbounded interval. Of particular importance is the exact form of the operators and metric spaces formulated in the earlier sections.
SYMMETRY BREAKING FOR GROUND-STATE SOLUTIONS OF HÉNON SYSTEMS IN A BALL
Authors: HE HAIYANG 
Published: December 2010

AbstractWe consider in this paper the problem
(1)
where Ω is the unit ball in ℝN centred at the origin, 0 ≤ α < pN,β > 0, N ≥ 3. Suppose qϵ → q as ϵ → 0+ and qϵ, q satisfy, respectively,

we investigate the asymptotic estimates of the ground-state solutions (uϵ, vϵ) of (1) as β → + ∞ with p, qϵ fixed. We also show the symmetry-breaking phenomenon with α, β fixed and qϵ → q as ϵ → 0+. In addition, the ground-state solution is non-radial provided that ϵ > 0 is small or β is large enough.
An audit of rubella IgG antibody status in antenatal women in a NHS Trust over 5 years (2005–2009)
Authors: MATTHEWS L. A. , LAWRANCE L. M. , GRAY D. , GRAY S. 
Published: December 2010

SUMMARYRubella, a vaccine-preventable infection. This study examined the antibody status of 11 987 pregnant women during 2005–2009. Results showed a non-significant decrease in those with antibody levels of <4·0 IU/ml from 29/2312 (1·3%) in 2005 to 21/2447 (0·9%) in 2009 (χ2for linear trend=0·279,P=0·56) but a significant increase in those with levels of <10 IU/ml from 88/2312 (3·8%) in 2005 to 124/2447 (5·1%) in 2009 (χ2for linear trend=10·27,P=0·001). In women born before 1983 (pre-pubertal vaccination) the proportion of first pregnancies with titres <4 IU was 1·1% (21/2002) compared to 3·4% (69/2022) in those born after 1983 (χ2=25·176,P<0·0001) and 2·2% (44/2002) for titres <10 IU compared to 14·0% (282/2022) for those born after 1983 (χ2=171·43,P<0·0001). The potential impact of the increase is difficult to determine, requiring further monitoring. This paper discusses the effect of changing immunization programmes on rubella susceptibility in pregnant women.
Detection rates of congenital heart disease in Guatemala
Authors: Trucco Sara M. , Barnoya Joaquin , Larrazabal Luis Alesandro , Castañeda Aldo , Teitel David F. 
Published: December 2010

AbstractObjectivesIn developing countries, congenital heart disease is often unrecognised, leading to serious morbidity and mortality. Guatemala is one of the few developing countries where expert paediatric cardiac treatment is available and affordable, and therefore early detection could significantly improve outcome. We assessed regional congenital heart disease detection rates in Guatemala, and determined whether they correlated with the regional human development index.MethodsWe retrospectively reviewed all new cardiac referrals made in 2006 to the Unidad de Cirugia Cardiovascular Pediatrica, the only paediatric cardiac centre in Guatemala. We calculated regional detection rates by comparing the number of congenital heart disease referrals with the expected incidence using the National Ministry of Health birth data. We then compared the regional detection rates with the human development index data published in the United Nations 2006 Development Program Report using Spearman’s rank correlation.ResultsAn estimated 3935 infants with cardiac defects were born in Guatemala in 2006, an expected 1380 (35%) of whom had severe forms. Overall, only 533 children (14%) with cardiac defects were referred. Of these, 62% had simple shunt lesions, 13% had cyanotic lesions, and 10% had left-sided obstructive lesions. Only 11.5% of referred patients were neonates. Regional detection rates, ranged 3.2–34%, correlated with the regional human development index (r = 0.75, p < 0.0001).ConclusionsCurrent detection of congenital heart disease in Guatemala is low and correlates with the regional human development index. Those detected are older and have less severe forms, suggesting a high mortality rate among Guatemalan neonates with complex cardiac defects.
Extended applications of the Amplatzer vascular plug IV in infants
Authors: Adelmann Roland , Windfuhr Alfred , Bennink Gerardus , Emmel Mathias , Sreeram Narayanswami 
Published: December 2010

AbstractObjectiveA variety of devices are available for transcatheter closure of unwanted shunts. We describe our experience with the use of the Amplatzer vascular plug IV in a consecutive series of infants.MethodsA total of eight consecutive infants – all born preterm at gestational ages ranging from 24 to 35 weeks – undergoing transcatheter closure of unwanted shunts – persistently patent arterial duct in five patients, an aorta to right atrium fistula in one, multiple aortopulmonary collateral vessels in one, and an azygos vein to left atrium connection in one – are described. Their age, from birth, ranged between 3 and 11 months, and weight between 2.6 and 11.3 kilograms. All devices were delivered using percutaneous arterial or venous vascular access via a large lumen (0.038 inch) 4-French delivery catheter.ResultsAll lesions could be successfully occluded using one or more devices. Device diameters ranged between 4 and 8 millimetres, and exceeded the minimum diameter of the target vessel by 1 to 2 millimetres. Successful occlusion was confirmed either directly at angiography or on follow-up echocardiography. Of the infants who were mechanically ventilated prior to the procedure, three could be successfully weaned following closure of the shunt. There were no procedure-related complications.ConclusionsThe new vascular plug IV is cheap and efficacious in closing a variety of shunts in young infants, and warrants further extended clinical application.
A workplace feasibility study of the effect of a minimal fruit intervention on fruit intake
Authors: Alinia Sevil , Lassen Anne D , Krogholm Kirstine S , Christensen Tue , Hels Ole H , Tetens Inge 
Published: December 2010

AbstractObjectiveThe main purpose of the study was to investigate the feasibility of using workplaces to increase the fruit consumption of participants by increasing fruit availability and accessibility by a minimal fruit programme. Furthermore, it was investigated whether a potential increase in fruit intake would affect vegetable, total energy and nutrient intake.DesignA 5-month, controlled, workplace study where workplaces were divided into an intervention group (IG) and a control group (CG). At least one piece of free fruit was available per person per day in the IG. Total fruit and dietary intake was assessed, using two 24 h dietary recalls at baseline and at endpoint.SettingEight Danish workplaces were enrolled in the study. Five workplaces were in the IG and three were in the CG.SubjectsOne hundred and twenty-four (IG, n 68; CG, n 56) healthy, mainly normal-weight participants were recruited.ResultsMean daily fruit intake increased significantly from baseline to endpoint only in the IG by 112(se 35) g. In the IG, mean daily intake of added sugar decreased significantly by 10·7(se 4·4) g, whereas mean daily intake of dietary fibre increased significantly by 3·0(se 1·1) g. Vegetable, total energy and macronutrient intake remained unchanged through the intervention period for both groups.ConclusionsThe present study showed that it is feasible to increase the average fruit intake at workplaces by simply increasing fruit availability and accessibility. Increased fruit intake possibly substituted intake of foods containing added sugar. In this study population the increased fruit intake did not affect total energy intake.