bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of timing and rate of marine cloud brightening aerosol injection on albedo changes during the diurnal cycle of marine stratocumulus clouds
Authors: Jenkins A. K. L. , Forster P. M. , Jackson L. S.
Published: September 2012

Abstract. The marine-cloud brightening geoengineering technique has been suggested as a~possible means of counteracting the positive radiative forcing associated with anthropogenic atmospheric CO2 increases. The focus of this study is to quantify the albedo response to aerosols injected into marine stratocumulus cloud from a point source at different times of day. We use a cloud-resolving model to investigate both weakly precipitating and non-precipitating regimes. Injection into both regimes induces a first indirect aerosol effect. Additionally, the weakly precipitating regime shows evidence of the second indirect aerosol effect and leads to cloud changes indicative of a regime change to more persistent cloud. This results in a cloud albedo increase up to six times larger than in the non-precipitating case. These indirect effects show considerable variation with injection at different times in the diurnal cycle. For the weakly precipitating case, aerosol injection results in average increases in cloud albedo of 0.28 and 0.17 in the early and mid morning (03:00:00 local time (LT) and 08:00:00 LT, respectively) and 0.01 in the evening (18:00:00 LT). No cloud develops when injecting into the cloud-free day (13:00:00 LT). However, the all-sky albedo increases (which include both the indirect and direct aerosol effects) are highest for early morning injection (0.11). Mid-morning and daytime injections produce increases of 0.06, with the direct aerosol effect compensating for the lack of cloud albedo perturbation during the cloud-free day. Evening injection results in an increase of 0.04. Penetration and accumulation of aerosols above the cloud top may lead to a reduction of all-sky albedo that tempers the cloud albedo increases. The apparent direct aerosol tempering effect increases with injection rate, although not enough to overcome the increase in all-sky planetary albedo resulting from increases in cloud albedo. For the weakly precipitating case considered, the optimal injection time for planetary albedo response is the early morning. Here, the cloud has more opportunity develop into a more persistent non-precipitating regime prior to the dissipative effects of solar heating. The effectiveness of the sea-spray injection method is highly sensitive to diurnal injection time and the direct aerosol effect of an intense aerosol point source. Studies which ignore these factors could overstate the effectiveness of the marine cloud brightening technique.
The Case for Gold Revisited: A Safe Haven Or A Hedge ?
Authors: Apak Sudi , Akman Vedat , Çankaya Serkan , Sonmezer Sıtkı
Published: September 2012

This paper attempts to analyze the relation among gold prices and other macroeconomic and financial variables and addresses the question whether gold is a safe haven or a hedge for investors. The study investigates the relationship by using an econometric analysis for top gold exporter and importer countries, for a sample period of 11 years from 2000 to 2011. The results are twofold (i) return of silver, USD returns and change in the volatility index influences gold returns positively whereas, Swiss Franc and Canadian Dollar returns influence gold returns negatively regardless of presence of the 2008 crisis. (ii) In times of stress, our findings indicate that Swiss Franc, Norwegian Krone and Canadian Dollar function as haven whereas, on average, Swiss Franc, Canadian Dollar and 10 year US treasuries function as a hedge against gold but the results show no evidence for the US dollar.
Errata
Authors: Akman Vedat
Published: September 2012

Corrections Of articles.
Estimation of Fracture Toughness by Testing Notched Fracture Specimens and Applying the Theory of Critical Distances
Authors: Cicero S. , Madrazo V. , Carrascal I. A.
Published: September 2012

This paper applies a methodology that allows the fracture toughness of a given material to be estimated by testing notched fracture toughness specimens and applying the Theory of Critical Distances, which requires the elastic stress field at the notch tip to be determined by finite elements simulation. This methodology, which is not intended to substitute any standardised fracture characterisation procedure, constitutes an alternative in those situations where pre-cracking processes may be too time-consuming, too expensive or, simply, cannot be performed. It comprises testing two notched specimens with different notch radii, defining the corresponding stress fields at fracture by using finite elements analysis, and applying the Theory of Critical Distances in order to calibrate the material’s critical distance and to apply the corresponding apparent fracture toughness formulation. The methodology has been applied to two different materials, PMMA and Al7075-T651, and the results have proven that, as long as the Theory of Critical Distances has been applied within its validity range, the fracture toughness estimations are highly accurate.
Automated monitoring of behavioural-based animal welfare indicators
Authors: Rushen J , Chapinal N , de Passilé AM
Published: September 2012

On-farm scoring of behavioural indicators of animal welfare is challenging but the increasing availability of low cost technology now makes automated monitoring of animal behaviour feasible. We discuss some of the issues with using automated methods to measure animal behaviour within the context of assessing animal welfare. Automated feeders (eg for dairy calves) can help measure the degree that animals are hungry and have potential to identify sick animals even in group housing. Such equipment is best used for longitudinal studies of individual animals rather than making comparisons between farms. Devices attached to animals (eg accelerometers or GPS devices) can help measure the activity levels of animals with a high degree of accuracy and can easily be transported between farms, making them best suited for welfare assessment at the group level. Automated image analysis has great potential to assess movement within groups of animals, but following individual animals can be difficult. The techniques have been validated against traditional methods (eg direct observation). The accuracy of measures taken automatically varies between methods but can be increased by combining measures. Technological developments have provided us with a variety of tools that can be used to monitor behaviour automatically, and these have great potential to improve our ability to monitor animal welfare indicators on-farm. However, it is important that methods be developed to measure a wider range of behaviour patterns. Animal welfare assessment schemes should not place undue emphasis on behavioural indicators solely on the basis that they can be monitored automatically.
A training programme to ensure high repeatability of injury scoring of dairy cows
Authors: Gibbons J , Vasseur E , Rushen J , de Passillé AM
Published: September 2012

Obtaining reliable welfare outcome measures from commercial farms can be challenging. We developed a training programme to train observers to score injuries of the tarsal joint, carpal joint and neck on dairy cows as part of an on-farm study. Twelve trainees were trained using protocols and photographs in a classroom session and on-farm visits. Continued repeatability checking was carried out during a refresher and mid-way assessment. Two trainers were used as the reference standard to which all trainees were compared. The study demonstrated that methods of scoring tarsal joint, carpal joint and neck injury can be learned by trainees from different backgrounds and high repeatability can be achieved and maintained at a very large regional or national level. Successful learning of injury scoring is dependent on protocols with strong definitions and photographs as well as repetitive training sessions. Additionally, continued repeatability checks are essential to ensure the reference standard continues to be met. This training programme can be used as a model to successfully train on-farm assessors.
Farm animal welfare: assessing risks attributable to the prenatal environment
Authors: Rutherford KMD , Donald RD , Arnott G , Rooke JA , Dixon L , Mehers JJM , Turnbull J , Lawrence AB
Published: September 2012

An ever-expanding scientific literature highlights the impact of the prenatal environment on many areas of biology. Across all major farmed species, experimental studies have clearly shown that prenatal experiences can have a substantial impact on outcomes relevant to later health, welfare and productivity. In particular, stress or sub-optimal nutrition experienced by the mother during pregnancy has been shown to have wide-ranging and important effects on how her offspring cope with their social, physical and infectious environment. Variation in the conditions for development provided by the reproductive tract or egg, for instance by altered nutritional supply or hormonal exposure, may therefore explain a large degree of variation in many welfare- and productivity-relevant traits. The scientific literature suggests a number of management practices for pre-birth/hatch individuals that could compromise their later welfare. Such studies may have relevance for the welfare of animals under human care, depending on the extent to which real life conditions involve exposure to these practices. Overall, the findings highlight the importance of extending the focus on animal welfare to include the prenatal period, an aspect which until recently has been largely neglected.
Long-Term Data from Fields Recovering after Sugarcane, Banana, and Pasture Cultivation in Ecuador
Authors: Myster Randall W.
Published: September 2012

I report here on an ongoing permanent plot study in areas recovering from agriculture in Ecuador. These plots were set up in 1995 at Maquipucuna Reserve where the forest is tropical lower montane. The study consists of replicate fields in three past crop types (Sugarcane, Banana, and Pasture) for a total of six fields. Each field was first divided into 25 continuous 2 m × 5 m subplots which together form a 10 m × 25 m plot with the longest side bordering the adjacent forest. Then starting in 1996, and continuing annually every year since, each subplot has been sampled for percent cover of all plants and diameter at breast height (dbh) for all trees whose dbh is greater than or equal to 1 cm. I have used that data in these published studies: (1) species composition and life form, richness, and basal area trends, (2) computation of all positive and negative pairwise species associations, (3) relationships between richness and productivity over time, (4) dominance-diversity curves, and (5) definition and quantification of old field plant communities. Finally with the help of the LTER program in Puerto Rico, this sampling continues, with 2012 marking the sixteenth year of continuous annual sampling.
Formation en intervention interculturelle dans un centre de réadaptation en déficience intellectuelle et trouble envahissant du développement
Authors: Saulnier Geneviève
Published: September 2012

Cet article fait suite à une expérimentation récente de formation continue offerte à des intervenants travaillant au Pavillon du Parc, un centre de réadaptation en déficience intellectuelle et trouble envahissant du développement (CRDITED). Cette expérimentation, qui consiste en une étape exploratoire d’un projet de recherche doctorale, s’inspire des fondements de l’approche interculturelle et des principes de l’apprentissage expérientiel. En revenant d’abord sur les principaux enjeux de l’intervention dans le champ de la santé et des services sociaux en contexte de diversité culturelle, cette contribution présentera le contexte institutionnel et social dans lequel s’est inscrite cette formation ainsi que les fondements à partir desquels elle a été construite. À partir des commentaires des intervenants lors de l’évaluation, la conclusion soulignera les forces et les limites de ce modèle de formation.
Precision Molecular Spectroscopy with Frequency Combs
Authors: Gatti Davide , Sala Tommaso , Marangoni Marco , Galzerano Gianluca , Gianfrani Livio
Published: September 2012

The advent of frequency combs has given tremendous impulse to the fields of high‐resolution molecular spectroscopy and trace sensing of multiple gases. The combs' secret lies in their fine, discrete, stable, reproducible, and controllable spectral structure, readily referable to the primary microwave standard. These features make combs ideal tools to obtain on one side precision as well as absolute frequency calibration in the spectroscopic detection of individual absorption lines and, on the other side, to develop a new class of spectrometers where broadband coupling of combs to passive optical cavities allows extreme sensitivity to be conjugated with spectral resolution, broad spectral coverage, and fast acquisition times.
Jury Comprehension of Expert Evidence
Authors: Wheate Rhonda M. , DesPortes Betty Layne
Published: September 2012

The effectiveness of expert testimony in litigation is limited by a factor independent of the strength of opinion testimony—the level of comprehension of the jurors. If the presentation of the expert testimony is not appropriate to the jurors' ability to understand the testimony and to apply the testimony to the issues in the case, the expert evidence is, at best, useless. Even more concerning is the fact that the inability to comprehend the expert testimony may lead the jurors to misapply the expert testimony, thereby negatively impacting the party's position at trial and thwarting the interests of justice. Research into factors affecting juror comprehension has reinforced some common assumptions about jurors' approaches to expert testimony while disproving other assumptions concerning limitations in complex litigation cases. Using the information from juror studies, several strategies and mechanisms for improving juror comprehension and use of expert testimony have been implemented in courts in the United States and the United Kingdom, but more research is necessary to ensure that jurors are able to effectively process and apply expert testimony in all cases.
Postpartum Psychosis
Authors: Friedman Susan Hatters
Published: September 2012

Postpartum psychosis, though rare, often has a dramatic presentation, usually after hospital discharge. Symptoms such as insomnia, hallucinations, delusions, abnormal mood, and agitation may occur. Potential risks include suicide, child neglect, or infanticide. Mothers usually require psychiatric hospitalization. Those who kill their infants under conditions of postpartum psychosis may qualify for infanticide or insanity defenses.
Shooting Distance: Estimation of
Authors: Zeichner Arie
Published: September 2012

The range from which a weapon has been fired is an important component in the reconstruction of firearm‐related cases.

A review of the methods for shooting distance estimation is provided. This refers to the examination of clothing targets, cadavers, and exhibits that cannot be processed in the laboratory. The methods include visual/microscopic examinations, color tests, and instrumental analysis of the firearm discharge residue (FDRs) deposits around the bullet entrance holes. The review does not cover shooting distance estimation for targets shot by pellet loads from shotguns.
Binary Li4Ti5O12‐Li2Ti3O7 Nanocomposite as an Anode Material for Li‐Ion Batteries
Authors: Zhu Guan‐Nan , Chen Long , Wang Yong‐Gang , Wang Con‐Xiao , Che Ren‐Chao , Xia Yong‐Yao
Published: September 2012

Li4Ti5O12 typically shows a flat charge/discharge curve, which usually leads to difficulty in the voltage‐based state of charge (SOC) estimation. In this study, a facile quench‐assisted solid‐state method is used to prepare a highly crystalline binary Li4Ti5O12‐Li2Ti3O7 nanocomposite. While Li4Ti5O12 exhibits a sudden voltage rise/drop near the end of its charge/discharge curve, this binary nanocomposite has a tunable sloped voltage profile. The nanocomposite exhibits a unique lamellar morphology consisting of interconnected nanograins of ≈20 nm size with a hierarchical nanoporous structure, contributing to an enhanced rate capability with a capacity of 128 mA h g−1 at a high C‐rate of 10 C, and excellent cycling stability.
Role of crystalline ethylene‐propylene copolymer on mechanical properties of impact polypropylene copolymer
Authors: Rungswang Wonchalerm , Saendee Phutsadee , Thitisuk Boonyakeat , Pathaweeisariyakul Thipphaya , Cheevasrirungruang Watcharee
Published: September 2012

Impact polypropylene copolymer (IPC) has been known as a multiphase material in which an ethylene‐propylene (EP) random copolymer, serves as toughening component, is dispersed in the homo‐polypropylene hPP matrix. The crystalline EP copolymer (cEP) is another component whose role and microstructural effect on the IPC properties has not been well understood. This work reveals the relationship between the microstructure of cEP and the mechanical properties, that is, impact and tensile resistance, of IPC. We clarify that IPC comprising high contents of cEP with long homo‐PP segment can extend the elongation at break while cEP with high content of homo‐PE segment contributes to high impact strength. Mechanisms for both of these processes have been proposed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Inflammatory Protein Expression in Adolescent and Adult Offspring of Type 1 Diabetic Mice
Authors: Dowling Daniel , Corrigan Niamh , Downey Paul , McAuliffe Fionnuala M.
Published: September 2012

AIMS

To measure inflammatory markers in offspring of pregestational type 1 diabetic mothers.

METHODS

Type 1 diabetes was induced in female C57BL6/J mice using streptozotocin. Offspring from control C57BL6/J and type 1 diabetic mothers were followed up to adulthood and blood was collected at 6 and 12 weeks of age, representing adolescent and adult stages respectively. Five well‐established inflammatory markers; Matrix metalloproteinase 9, soluble E‐selectin, sICAM‐1, sVCAM‐1, and total plasminogen activator inhibitor‐1 (PAI‐1) were measured on an inflammatory multiplex assay in plasma.

RESULTS

Blood plasma from adolescent offspring from diabetic mothers displayed an increase in all five inflammatory markers when compared to controls, and there was a highly significant increase in sVCAM‐1 (64.56 ± 20.1 vs. 33.8 ± 20.75; p < 0.01) and tPAI‐1 (0.05 ± 0.02 vs. 0.02 ± 0.01; p < 0.01) expression.

CONCLUSION

Our findings show that inflammatory markers are increased in offspring of pregestational diabetic mothers. This may represent a mechanism for increased risk of cardiovascular disease evident in these offspring.
Engineering protein filaments with enhanced thermostability for nanomaterials
Authors: Glover Dominic J. , Giger Lars , Kim Jihyun R. , Clark Douglas S.
Published: September 2012

Self‐assembling protein templates have enormous potential as biomaterials for the fabrication of multifunctional nanostructures that require precise positioning of individual molecules in regular patterns over large surface areas. Furthermore, the development of protein templates that are stable under extreme conditions of heat or chemical denaturants will expand processing conditions and end‐use applications for biomaterials that require exceptional stability and robustness. In the present work, we characterized the high thermal stability of a filamentous protein template, the γ‐prefoldin (γPFD) from the hyperthermophile Methanocaldococcus jannaschii, and subsequently used rational design to further enhance the filament's thermal stability for application as a biotemplate in the creation of platinum nanowires. The γPFD assembles into long fibers with lengths that exceed 2 μm, which when heated to various temperatures and examined by transmission electron microscopy, revealed a Tm of 93°C for the quaternary filament structure. Subsequently, we increased the hydrophobicity of the α‐helices of the γPFD's coiled‐coil, which appeared to strengthen the filamentous structure, leading to filaments of greater length at elevated temperatures. These enhanced filaments functioned as templates for the synthesis of platinum nanowires at unprecedented temperatures, and may create new opportunities for other applications of nanoscale biotemplates that require exceptional thermal stability.

See accompanying commentary by Jonathan S. Dordick DOI: 10.1002/biot.201200338
Strategies for biological heart valve replacement: Stentless xenografts fail to evolve into an alternative pulmonary valve substitute in a Ross procedure
Authors: Weimar Timo , Roser Detlef , Liebrich Markus , Horke Alexander , Doll Nicolas , Hemmer Wolfgang B.
Published: September 2012

The Ross operation is a complex procedure for aortic valve replacement in which the pulmonary autograft is replaced by a homograft. However, homograft availability is becoming limited. This report evaluates the performance of porcine stentless prostheses as alternative pulmonary substitutes. Echocardiographic results from two patient cohorts were compared at time of discharge and 1 year after a Ross procedure. Thirty‐three patients (median age 42 years, range 17–62 years, 76% male) received a stentless prosthesis (median size 25.6 mm, range 25–29 mm) for right ventricular outflow tract reconstruction. Clinical data were not significantly different from 106 patients (median age 47 years, range 2–68 years, 75% male) who received cryopreserved homografts (median size 26 mm, range 20–33 mm). At time of discharge, peak pressure gradients (ΔPmax) across the stentless valve (median ΔPmax 13 mmHg, range 2–26 mmHg) were higher compared to homografts (median ΔPmax 7 mmHg, range 1–32 mmHg, p<0.001). At 1 year, gradients increased in both groups, but were significantly higher across stentless valves (median ΔPmax 23 mmHg, range 10–81 mmHg vs. median ΔPmax 13 mmHg, range 2–74 mmHg, p<0.001). Eleven patients (33%) in the stentless‐valve group were classified “at risk” with a ΔPmax of ≥30 mmHg. Four of them (12%) had to be re‐operated. In conclusion, stentless valves showed higher pressure gradients and their performance was inferior to cryopreserved homografts.

See accompanying commentary by Ulrich Stock DOI: 10.1002/biot.201200341
Sterically Hindered o‐Quinone Annulated with Dithiete: A Molecule Comprising Diolate and Dithiolate Coordination Sites
Authors: Cherkasov Vladimir K. , Abakumov Gleb A. , Fukin Georgy K. , Klementyeva Svetlana V. , Kuropatov Viacheslav A.
Published: September 2012

A new stable sterically hindered o‐quinone annelated with a 1,2‐dithiete ring was prepared by using mild conditions. The skeleton of the compound comprises diolate and dithiolate functions that have the potential to bind metals leading to the corresponding complexes. The reactivity of this compound as a ligand with respect to both coordination sites was studied. Reactions with metals indicate that the o‐quinone function is reduced in the first stage to give semiquinonate and catecholate complexes. The dithiolate coordination site was involved in the reaction in a few cases only after diolate was bound. A trinuclear manganese complex with coordination on both sites was obtained and characterized by EPR spectroscopy. The electrochemical study of this quinone fused with dithiete is reported.
Human CD22 cannot fully substitute murine CD22 functions in vivo, as shown in a new knockin mouse model
Authors: Wöhner Miriam , Born Stefanie , Nitschke Lars
Published: September 2012

CD22, an inhibitory co‐receptor of the B‐cell receptor, shows a B‐cell‐specific expression pattern and is expressed on most B‐cell lymphomas. The anti‐CD22 antibody Epratuzumab is in clinical trials for B‐cell non‐Hodgkin lymphoma and systemic lupus erythematosus, but shows a mostly unknown mode of action. We generated a new mouse model that expresses human CD22 instead of murine CD22 (Huki CD22 mice), in which human CD22 can be targeted. Expression of human CD22 on the B cells of Huki CD22 mice does not generally interfere with B‐cell development. However, Huki CD22 mice show a reduction of the population of mature recirculating B cells in the bone marrow and reduced transitional and marginal zone B cells in the spleen, phenotypes resembling that of CD22‐deficient mice. Similarly, enhanced BCR‐induced Ca2+ signalling is observed in Huki CD22 mice, which also mount normal immune responses toward different classes of antigens. Huki CD22 B cells show a normal anti‐hCD22 antibody‐mediated endocytosis. In conclusion, human CD22 cannot fully substitute for murine CD22 functions, possibly due to the changed intracellular tail of the protein or due to lower expression levels. Huki CD22 mice are a valuable new model for both antibody‐ and immunotoxin‐mediated targeting of human CD22.
Preparation of Various Prussian Blue Analogue Hollow Nanocubes with Single Crystalline Shells
Authors: Hu Ming , Torad Nagy L. , Yamauchi Yusuke
Published: September 2012

We report the preparation of monocrystalline Prussian blue (PB) analogue hollow nanocubes by applying a controlled chemical etching method with assistance of polyvinylpyrrolidone (PVP). The hollow particles obtained possess the original single‐crystalline structures, with retention of the high surface areas. Our synthetic route based on chemical etching is quite simple, and it can be scaled up for mass production.
Synthesis and Crystallochemical Characterisation of the Intermetallic Phases La(AgxMg1–x)12 (0.11 ≤ x ≤ 0.21), LaAg4+xMg2–x (–0.15 ≤ x ≤ 1.05) and LaAg2+xMg2–x (0 < x ≤ 0.45)
Authors: Solokha Pavlo , De Negri Serena , Pavlyuk Volodymyr , Saccone Adriana , Fadda Giuseppe
Published: September 2012

The crystal structures of three new La–Ag–Mg ternary phases were solved and refined from X‐ray diffraction data recorded on single crystals. All the studied phases show wide homogeneity regions extending at a constant La concentration. The Mg‐rich compound La(AgxMg1–x)12 (0.11 ≤ x ≤ 0.21) crystallises with a large tetragonal unit cell [I, I41/amd, tI208, own str. type, Z = 16, a = 10.1686(10), c = 46.539(5) Å, R1 = 0.013, wR2 = 0.025, x = 0.12]. The Ag‐rich phase LaAg4+xMg2–x (–0.15 ≤ x ≤ 1.05) shows two structural modifications: body‐centred tetragonal for an Ag content lower than ca. 70 at.‐% [II, I4/mmm, tI14, YbAl4Mo2‐type, Z = 2, a = 7.1995(3), c = 5.5996(2) Å, R1 = 0.031, wR2 = 0.081, x = 0.4] and primitive tetragonal for a higher Ag‐content [III, P4/nmm, tP14, own str. type, Z = 2, a = 7.2227(4), c = 5.4433(9) Å, R1 = 0.013, wR2 = 0.030, x = 0.9]. These two structural models are group‐subgroup related (LaAg5Mg is the k2 subgroup of LaAg4Mg2) as usual for second‐order transformations. The LaAg2+xMg2–x phase (0 < x ≤ 0.45) crystallises with an orthorhombic unit cell [IV, Cmcm, oS20, own str. type, Z = 4, a = 4.805(1), b = 17.258(4), c = 5.527(1) Å, R1 = 0.029, wR2 = 0.081, x = 0.25]. In order to gain insights into their bonding peculiarities, calculations of the electronic structures (LMTO approach) were performed on idealised stoichiometric models of the studied compounds representing a chemical modelling of mixed occupations. We also computed the structural parameters of the Ag‐rich phases and the vibrational properties of LaAg4+xMg2–x within the pseudopotential approach in generalised‐gradient approximation (GGA).
Steric Effect of a Phosphane Ligand on the Equilibrium of Ge–Ge Bond Formation at a Platinum Center
Authors: Arii Hidekazu , Watanabe Nakako , Mochida Kunio , Kawashima Takayuki
Published: September 2012

Reactions of zero‐valent platinum complexes having a diphosphane ligand with arylgermanes ArGeH3 [Ar = 2,4,6‐trimethylphenyl (Mes); 2,4,6‐triethylphenyl (TEP)] in a 1:2 molar ratio yield several bis(germyl)platinum complexes. The complex containing a five‐membered chelate ligand (dppe) is thermally stable even at 80 °C. Analogues bearing a six‐membered chelate ligand (dppp) were converted into the digermylplatinum complex through a 1,2‐germyl migration, and an equilibrium between the bis(germyl) and digermyl complexes was observed. In a comparison of the crystal structures, the bite angle of dppp is significantly larger than that of dppe, causing a reduction of the phosphane–germyl ligand distance. The 1,2‐germyl migration of the platinum center to the other germanium atom contributes to the decrease in steric repulsion between the phosphane and germyl ligands.
Hydrogen‐Bonding Thiourea Organocatalysts: The Privileged 3,5‐Bis(trifluoromethyl)phenyl Group
Authors: Lippert Katharina M. , Hof Kira , Gerbig Dennis , Ley David , Hausmann Heike , Guenther Sabine , Schreiner Peter R.
Published: September 2012

We present evidence that the privileged use of the 3,5‐bis(trifluoromethyl)phenyl group in thiourea organocatalysis is due to the involvement of the ortho‐CH bond in the binding event with Lewis‐basic sites. We utilized a combination of low‐temperature IR spectroscopy, 2D NMR spectroscopy, nano‐MS (ESI) investigations, as well as density functional theory computations [M06/6‐31+G(d,p), including solvent corrections as well as natural bond orbital and atoms‐in‐molecules analyses] to support our conclusions that bear implications for catalyst design.
Evidence of exposure to aristolochic acid in patients with urothelial cancer from a Balkan endemic nephropathy region of Romania
Authors: Schmeiser Heinz H. , Kucab Jill E. , Arlt Volker M. , Phillips David H. , Hollstein Monica , Gluhovschi Gheorghe , Gluhovschi Cristina , Modilca Mirela , Daminescu Liviu , Petrica Ligia , Velciov Silvia
Published: September 2012

Recently, chronic Aristolochia poisoning was found responsible for the aetiology of Balkan endemic nephropathy (BEN) in Croatia, Serbia, and Bosnia, and diet was the likely route of exposure to aristolochic acid (AA). BEN, often associated with an increased incidence of upper urinary tract carcinoma (UUC), also affects residents of certain rural villages in Romania. AA is a nephrotoxin and human carcinogen that forms DNA adducts after metabolic activation, which induce characteristic TP53 mutations in urothelial tumours. Here we present the first evidence linking AA exposure to UUC in residents of an endemic region in the Romanian Mehedinti County. DNA was extracted from kidney and tumour tissue of seven patients who underwent nephroureterectomy for UUC and resided in BEN villages (endemic group). Five patients with UUC from nonendemic villages served as controls. AA‐DNA adducts (7‐(deoxyadenosin‐N6‐yl)‐aristolactam I), established biomarkers of AA exposure, were identified by 32P‐postlabelling in renal DNA of six patients from the endemic group and in one of the nonendemic group (adduct levels ranged from 0.3 to 6.5 adducts per 108 nucleotides). Additionally, an A to T transversion in TP53, a base substitution characteristic of AA mutagenic activity was found in urothelial tumour DNA of one patient from the endemic group. Our results provide a molecular link to the cause of urothelial tumours in BEN regions of Romania indicating that AA is the common aetiological agent for BEN across its numerous geographical foci. Environ. Mol. Mutagen., 2012. © 2012 Wiley Periodicals, Inc.
Probabilistic Multiobjective Operation Management of MicroGrids With Hydrogen Storage and Polymer Exchange Fuel Cell Power Plants
Authors: Niknam T. , Golestaneh F.
Published: September 2012

This paper models and solves the operation management problem of MicroGrids (MGs) including cost and emissions minimization under uncertain environment. The proposed model emphasizes on fuel cells (FCs) as a prime mover of combined heat and power (CHP) systems. An electro‐chemical model of the proton exchange membrane fuel cell (PEMFC) is used and linked to the daily operating cost and emissions of the MGs. A reformer is considered to produce hydrogen for PEMFCs. Moreover, in high thermal load intervals, in order to make the MG more efficient, a part of produced hydrogen is stored in a hydrogen tank. The stored hydrogen can be reused by PEMFCs to generate electricity or be sold to other hydrogen consumers. A probabilistic optimization algorithm is devised which consists of 2m + 1 point estimate method to handle the uncertainty in input random variables (IRVs) and a multi‐objective Self‐adaptive Bee Swarm Optimization (SBSO) algorithm to minimize the cost and emissions simultaneously. Several techniques are proposed in the SBSO algorithm to make it a powerful black‐box optimization tool. The efficiency of the proposed approach is verified on a typical grid‐connected MG with several distributed energy sources.
Regulation of microglia activation and deactivation by nuclear receptors
Authors: Saijo Kaoru , Crotti Andrea , Glass Christopher K.
Published: September 2012

Microglia cells function as sentinels for innate immunity in the central nervous system (CNS). To perform this function, microglia express a diverse set of pattern recognition receptors (PRRs) for pathogen‐associated molecular patterns (PAMPs) that include Toll‐like receptors (TLRs) and inflammasomes. Several members of the TLR and inflammasome family also recognize endogenously derived molecules that are generated as a consequence of tissue injury or other pathological processes. Recognition of PAMPs or endogenous ligands by PRRs in microglia induces the robust activation of innate immune responses leading to the production of proinflammatory mediators and the activation of adaptive immunity. Activation of microglia is essential for clearance of infection and repair of tissue injury. However, uncontrolled inflammatory responses of microglia are also thought to contribute to the severity of many neurodegenerative diseases. Thus, activation of microglia must be properly and tightly regulated to maintain normal tissue homeostasis. Several mechanisms have been identified that appear to function in the active maintenance of quiescence under normal conditions and/or re‐establish this state following resolution of infection or injury. These mechanisms involve communication with neurons and other glia through secreted molecules or surface expressing receptors as well as actions of members of the nuclear receptor (NR) superfamily of transcription factors. Here, we review recent advances in our understanding of the regulation of microglia activation and deactivation with a focus on counter‐regulation of microglia activation by nuclear receptors. © 2012 Wiley Periodicals, Inc.
Using HPV prevalence to predict cervical cancer incidence
Authors: Sharma Monisha , Bruni Laia , Diaz Mireia , Castellsagué Xavier , Sanjosé Silvia de , Bosch F. Xavier , Kim Jane J.
Published: September 2012

Knowledge of a country's cervical cancer (CC) burden is critical to informing decisions about resource allocation to combat the disease; however, many countries lack cancer registries to provide such data. We developed a prognostic model to estimate CC incidence rates in countries without cancer registries, leveraging information on human papilloma virus (HPV) prevalence, screening, and other country‐level factors. We used multivariate linear regression models to identify predictors of CC incidence in 40 countries. We extracted age‐specific HPV prevalence (10‐year age groups) by country from a meta‐analysis in women with normal cytology (N = 40) and matched to most recent CC incidence rates from Cancer Incidence in Five Continents when available (N = 36), or Globocan 2008 (N = 4). We evaluated country‐level behavioral, economic, and public health indicators. CC incidence was significantly associated with age‐specific HPV prevalence in women aged 35–64 (adjusted R‐squared 0.41) (“base model”). Adding geographic region to the base model increased the adjusted R‐squared to 0.77, but the further addition of screening was not statistically significant. Similarly, country‐level macro‐indicators did not improve predictive validity. Age‐specific HPV prevalence at older ages was found to be a better predictor of CC incidence than prevalence in women under 35. However, HPV prevalence could not explain the entire CC burden as many factors modify women's risk of progression to cancer. Geographic region seemed to serve as a proxy for these country‐level indicators. Our analysis supports the assertion that conducting a population‐based HPV survey targeting women over age 35 can be valuable in approximating the CC risk in a given country.
Does acupuncture activate endogenous analgesia in chronic whiplash‐associated disorders? A randomized crossover trial
Authors: Tobbackx Y. , Meeus M. , Wauters L. , De Vilder P. , Roose J. , Tom Verhaeghe J. , Nijs
Published: September 2012

Background

Many patients with chronic pain, including those with chronic whiplash‐associated disorders (WAD), show features of central sensitization. Randomized trials examining whether treatments are able to influence the process of central sensitization in patients with chronic WAD are emerging. Therefore, the present study aimed at examining whether acupuncture results in activation of endogenous analgesia and relief in symptoms in patients with chronic WAD.

Methods

In this randomized crossover pilot trial with blinded assessors, each patient (n = 39) received two treatment sessions of identical duration, with acupuncture and relaxation therapy randomly crossed over in visit 2. Primary outcome measurement included immediate activation of endogenous analgesia i.e., pressure pain sensitivity and conditioned pain modulation. Secondary outcome measurements included pain relief and reduced disability level.

Results

Local pressure pain sensitivity at baseline and during conditioned pain modulation decreased significantly more following acupuncture compared with relaxation (time × group interactions: p < 0.001), both in the neck and at a site distinct from the painful region. When comparing the effects of acupuncture versus relaxation, no differences were observed on conditioned pain modulation, temporal summation of pressure pain, neck disability or symptom severity (all p‐values >0.05).

Conclusion

It was shown that one session of acupuncture treatment results in acute improvements in pressure pain sensitivity in the neck and calf of patients with chronic WAD. Acupuncture had no effect on conditioned pain modulation or temporal summation of pressure pain. Both acupuncture and relaxation appear to be well‐tolerated treatments for people with chronic WAD. These findings suggest that acupuncture treatment activates endogenous analgesia in patients with chronic WAD.
Neocellularization and neovascularization of nanosized bioactive glass‐coated decellularized trabecular bone scaffolds
Authors: Gerhardt L.‐C. , Widdows K. L. , Erol M. M. , Nandakumar A. , Roqan I. S. , Ansari T. , Boccaccini A.R.
Published: September 2012

In this study, the in vivo recellularization and neovascularization of nanosized bioactive glass (n‐BG)‐coated decellularized trabecular bone scaffolds were studied in a rat model and quantified using stereological analyses. Based on the highest amount of vascular endothelial growth factor (VEGF) secreted by human fibroblasts grown on n‐BG coatings (0–1.245 mg/cm2), decellularized trabecular bone samples (porosity: 43–81%) were coated with n‐BG particles. Grown on n‐BG particles at a coating density of 0.263 mg/cm2, human fibroblasts produced 4.3 times more VEGF than on uncoated controls. After 8 weeks of implantation in Sprague–Dawley rats, both uncoated and n‐BG‐coated samples were well infiltrated with newly formed tissue (47–48%) and blood vessels (3–4%). No significant differences were found in cellularization and vascularization between uncoated bone scaffolds and n‐BG‐coated scaffolds. This finding indicates that the decellularized bone itself may exhibit growth‐promoting properties induced by the highly interconnected pore microarchitecture and/or proteins left behind on decellularized scaffolds. Even if we did not find proangiogenic effects in n‐BG‐coated bone scaffolds, a bioactive coating is considered to be beneficial to impart osteoinductive and osteoconductive properties to decellularized bone. n‐BG‐coated bone grafts have thus high clinical potential for the regeneration of complex tissue defects given their ability for recellularization and neovascularization. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 827–841, 2013.
An analytical method for computing atomic contact areas in biomolecules
Authors: Mach Paul , Koehl Patrice
Published: September 2012

We propose a new analytical method for detecting and computing contacts between atoms in biomolecules. It is based on the alpha shape theory and proceeds in three steps. First, we compute the weighted Delaunay triangulation of the union of spheres representing the molecule. In the second step, the Delaunay complex is filtered to derive the dual complex. Finally, contacts between spheres are collected. In this approach, two atoms i and j are defined to be in contact if their centers are connected by an edge in the dual complex. The contact areas between atom i and its neighbors are computed based on the caps formed by these neighbors on the surface of i; the total area of all these caps is partitioned according to their spherical Laguerre Voronoi diagram on the surface of i. This method is analytical and its implementation in a new program BallContact is fast and robust. We have used BallContact to study contacts in a database of 1551 high resolution protein structures. We show that with this new definition of atomic contacts, we generate realistic representations of the environments of atoms and residues within a protein. In particular, we establish the importance of nonpolar contact areas that complement the information represented by the accessible surface areas. This new method bears similarity to the tessellation methods used to quantify atomic volumes and contacts, with the advantage that it does not require the presence of explicit solvent molecules if the surface of the protein is to be considered. © 2012 Wiley Periodicals, Inc.
Declining liver utilization for transplantation in the United States and the impact of donation after cardiac death
Authors: Orman Eric S. , Barritt Sidney A. , Wheeler Stephanie B. , Hayashi Paul H.
Published: September 2012

Worsening donor liver quality resulting in decreased organ utilization may be contributing to the recent decline in liver transplants nationally. We sought to examine trends in donor liver utilization and the relationship between donor characteristics and nonuse. We used the United Network for Organ Sharing database to review all deceased adult organ donors in the United States from whom at least 1 solid organ was transplanted into a recipient. Trends in donor characteristics were examined. Multivariate logistic regression was used to evaluate the association between donor characteristics and liver nonuse between 2004 and 2010. Population attributable risk proportions were determined for donor factors associated with nonuse. We analyzed 107,259 organ donors. The number of unused livers decreased steadily from 1958 (66% of donors) in 1988 to 841 (15%) in 2004 but then gradually increased to 1345 (21%) in 2010. The donor age, the body mass index (BMI), and the prevalence of diabetes and donation after cardiac death (DCD) all increased over time, and all 4 factors were independently associated with liver nonuse. DCD had the highest adjusted odds ratio (OR) for nonuse, and the odds increased nearly 4-fold between 2004 [OR = 5.53, 95% confidence interval (CI) = 4.57-6.70] and 2010 (OR = 21.31, 95% CI = 18.30-24.81). The proportion of nonuse attributable to DCD increased from 9% in 2004 to 28% in 2010. In conclusion, the proportion of donor livers not used has increased since 2004. Older donor age, greater BMI, diabetes, and DCD are all independently associated with nonuse and are on the rise nationally. Current trends may lead to significant declines in liver transplant availability. Liver Transpl 19:59–68, 2013. © 2012 AASLD.
Synthesis of Novel Core Cross‐Linked Star‐Based Polyrotaxane End‐Capped via “CuAAC” Click Chemistry
Authors: Fu Qiang , Ren Jing M. , Tan Shereen , Xu Jiangtao , Qiao Greg G.
Published: September 2012

The first example of core cross‐linked star (CCS) polyrotaxane was prepared using the poly(ϵ‐caprolactone) (PCL) CCS three‐dimensional (3D) scaffold. The 3D CCS polymer was firstly prepared through the “arm‐first” approach. Then, the “arms” of the resultant PCL CCS polymer were threaded with α‐cyclodextrins (α‐CDs). The threaded α‐CDs were permanently locked by the “click” reaction of terminal alkyne functionalities of the star polymers with the azide‐functionalized end caps to afford the CCS polyrotaxanes. All analytical results confirm the formation of the CCS polyrotaxanes and reveal their characteristics, including fluorescence under UV, a channel‐type crystalline structure, a two‐step thermal decomposition, and a unique core‐shell structure in great contrast to the polymer precursors.
Two Tikhonov‐type regularization methods for inverse source problem on the Poisson equation
Authors: Zhao Jingjun , Liu Songshu , Liu Tao
Published: September 2012

In this paper, we investigate a problem of the identification of an unknown source on Poisson equation from some fixed location. A conditional stability estimate for an inverse heat source problem is proved. We show that such a problem is mildly ill‐posed and further present two Tikhonov‐type regularization methods (a generalized Tikhonov regularization method and a simplified generalized Tikhonov regularization method) to deal with this problem. Convergence estimates are presented under the a priori choice of the regularization parameter. Numerical results are presented to illustrate the accuracy and efficiency of our methods. Copyright © 2012 John Wiley & Sons, Ltd.
Flavone potently stimulates an apical transporter for flavonoids in human intestinal Caco‐2 cells
Authors: Lies Barbara , Martens Stefan , Schmidt Sabine , Boll Michael , Wenzel Uwe
Published: September 2012

Scope

Based on the studies suggesting that active transport mechanisms contribute to the absorption of flavonoids into human intestinal Caco‐2 cells, we here used the structurally similar fluorescent rhodamine 123 to test a possible influence of flavonoids on its uptake.

Methods and results

Rhodamine absorption displayed saturation kinetics with a Km of 1.1 μM and a pH‐optimum of 8.5 and was stimulated by flavone four‐fold in its Vmax. Ring C of the other 16 flavonoids tested turned out to be of special importance in order to act as potent inhibitors for rhodamine transport, with a positive charge there, as present in the anthocyanidins, or a 2,3 double bond together with an aromatic ring fused to position 2, as present in flavones and flavonols, being essential structural requirements. Flavone‐stimulated rhodamine uptake was unaffected by classical substrates of organic cation transporters or inhibitors of adenosine triphosphate (ATP)‐dependent efflux pumps. Also, inhibitors of mitogen‐activated protein kinases or tyrosine kinases did not influence the transport, whose stimulation, however, was essentially dependent on the simultaneous presence of flavone. The existence of a flavone‐activated apical flavonoid transporter in Caco‐2 cells was finally associated with the potently diminished transepithelial apical to basolateral fluxes of 14C‐kaempferol in the presence of competing unlabeled flavonoid substrates.

Conclusion

In conclusion, flavone activates an as yet unidentified transporter for flavonoids in the apical membrane of Caco‐2 cells.