bluuebunny/crossref_metadata_2025 huggingface dataset:
Consensus analysis of continuous‐time second‐order multi‐agent systems with nonuniform time‐delays and switching topologies
Authors: Zhang Wenguang , Liu Jizhen , Zeng Deliang , Yang Tingting
Published: January 2013

In this study, consensus problems for second‐order multi‐agent systems with nonuniform and switching topologies are investigated. Each agent has a self‐delay, and each delay is independent of the others. As a measure of the disagreement dynamics, a class of positive semi‐definite Lyapunov–Krasovskii functions are introduced. Using algebraic graph theory and these Lyapunov–Krasovskii functions, sufficient conditions are derived by contradiction under which all agents asymptotically reach consensus. Finally, the effectiveness of the obtained theoretical results is demonstrated through numerical simulations.
Curcumin and liver disease
Authors: Vera‐Ramirez Laura , Pérez‐Lopez Patricia , Varela‐Lopez Alfonso , Ramirez‐Tortosa MCarmen , Battino Maurizio , Quiles José L.
Published: January 2013

Liver diseases pose a major medical problem worldwide and a wide variety of herbs have been studied for the management of liver‐related diseases. In this respect, curcumin has long been used in traditional medicine, and in recent years it has been the object of increasing research interest. In combating liver diseases, it seems clear that curcumin exerts a hypolipidic effect, which prevents the fatty acid accumulation in the hepatocytes that may result from metabolic imbalances, and which may cause nonalcoholic steatohepatitis. Another crucial protective activity of curcumin, not only in the context of chronic liver diseases but also regarding carcinogenesis and other age‐related processes, is its potent antioxidant activity, which affects multiple processes and signaling pathways. The effects of curcumin on NF‐κβ are crucial to our understanding of the potent hepatoprotective role of this herb‐derived micronutrient. Because curcumin is a micronutrient that is closely related to cellular redox balance, its properties and activity give rise to a series of molecular reactions that in every case and biological situation affect the mitochondria. © 2013 BioFactors, 39(1):88–100, 2013
Curcumin in various cancers
Authors: Shehzad Adeeb , Lee Jaetae , Lee Young Sup
Published: January 2013

Curcumin (diferuloylmethane), an active constituent of turmeric, is a well‐described phytochemical, which has been used since ancient times for the treatment of various diseases. The dysregulation of cell signaling pathways by the gradual alteration of regulatory proteins is the root cause of cancers. Curcumin modulates regulatory proteins through various molecular mechanisms. Several research studies have provided in‐depth analysis of multiple targets through which curcumin induces protective effects against cancers including gastrointestinal, genitourinary, gynecological, hematological, pulmonary, thymic, brain, breast, and bone. The molecular mechanisms of action of curcumin in treating different types of cancers remain under investigation. The multifaceted role of this dietary agent is mediated through its inhibition of several cell signaling pathways at multiple levels. Curcumin has the ability to inhibit carcinogenicity through the modulation of the cell cycle by binding directly and indirectly to molecular targets including transcription factors (NF‐kB, STAT3, β‐catenin, and AP‐1), growth factors (EGF, PDGF, and VEGF), enzymes (COX‐2, iNOS, and MMPs), kinases (cyclin D1, CDKs, Akt, PKC, and AMPK), inflammatory cytokines (TNF, MCP, IL‐1, and IL‐6), upregulation of proapoptotic (Bax, Bad, and Bak) and downregulation of antiapoptotic proteins (Bcl2 and Bcl‐xL). A variety of animal models and human studies have proven that curcumin is safe and well tolerated even at very high doses. This study elaborates the current understanding of the chemopreventive effects of curcumin through its multiple molecular pathways and highlights its therapeutic value in the treatment and prevention of a wide range of cancers. © 2013 BioFactors, 39(1):56–68, 2013
Facile Synthesis of Thermal‐ and Photostable Titania with Paramagnetic Oxygen Vacancies for Visible‐Light Photocatalysis
Authors: Zou Xiaoxin , Liu Jikai , Su Juan , Zuo Fan , Chen Jiesheng , Feng Pingyun
Published: January 2013

A novel dopant‐free TiO2 photocatalyst (Vo.‐TiO2), which is self‐modified by a large number of paramagnetic (single‐electron‐trapped) oxygen vacancies, was prepared by calcining a mixture of a porous amorphous TiO2 precursor, imidazole, and hydrochloric acid at elevated temperature (450 °C) in air. Control experiments demonstrate that the porous TiO2 precursor, imidazole, and hydrochloric acid are all necessary for the formation of Vo.‐TiO2. Although the synthesis of Vo.‐TiO2 originates from such a multicomponent system, this synthetic approach is facile, controllable, and reproducible. X‐ray diffraction, XPS, and EPR spectroscopy reveal that the Vo.‐TiO2 material with a high crystallinity embodies a mass of paramagnetic oxygen vacancies, and is free of other dopant species such as nitrogen and carbon. UV/Vis diffuse‐reflectance spectroscopy and photoelectrochemical measurement demonstrate that Vo.‐TiO2 is a stable visible‐light‐responsive material with photogenerated charge separation efficiency higher than N‐TiO2 and P25 under visible‐light irradiation. The Vo.‐TiO2 material exhibits not only satisfactory thermal‐ and photostability, but also superior photocatalytic activity for H2 evolution (115 μmol h−1 g−1) from water with methanol as sacrificial reagent under visible light (λ>400 nm) irradiation. Furthermore, the effects of reaction temperature, ratio of starting materials (imidazole:TiO2 precursor) and calcination time on the photocatalytic activity and the microstructure of Vo.‐TiO2 were elucidated.
Magnesium Catalysis of Imine Hydroboration
Authors: Arrowsmith Merle , Hill Michael S. , Kociok‐Köhn Gabriele
Published: January 2013

The β‐diketiminato magnesium alkyl complex [LMgnBu] (L=CH{CMe(NDipp)}2, Dipp=diisopropylphenyl) is shown to be a highly effective precatalyst for the hydroboration of alkyl and aryl substituted aldimines and ketimines with pinacol borane (HBpin). Catalysis is proposed to occur through a sequence of MgN/BH metathesis and rate‐determining MgH/NC insertion steps, a proposal strongly supported by stoichiometric studies and kinetic analysis. The reactions are observed to proceed through the intermediacy of well‐defined magnesium amides, two examples of which have been isolated and structurally characterized. Mechanistic investigations suggest that the catalytic rate‐determining process occurs at an isolated magnesium center and requires the presence of two molecules of the imine substrate for effective turnover. This latter observation is rationalized as a requirement for the secondary substrate molecule to displace HBpin from the coordination sphere of the catalytic magnesium center.
Dynamic Electrosorption Analysis as an Effective Means to Characterise the Structure of Bulk Graphene Assemblies
Authors: Zhu Junwu , Cheng Chi , Yang Xiaowei , Wang Yufei , Qiu Ling , Li Dan
Published: January 2013

Restacking of graphene sheets to a graphite‐like structure is a prevailing problem that is known to compromise the performance of individual graphene sheets in an assembled bulk form. To address this common problem efficiently and monitor the structure and quality of graphene products comprehensively, it is highly desirable to develop reliable metrology techniques for characterising graphene‐based materials on a bulk assembly level and in a quantitative manner. Here, by revisiting the physicochemical principle of electrosorption, we propose a simple electrochemical approach, namely dynamic electrosorption analysis (DEA), as an easily accessible and effective technique for evaluation of the self‐stacking behaviour of graphene. Taking multilayered chemically converted graphene films as a model, we demonstrate that the DEA technique can effectively reveal very subtle variation in accessible surface area and pore size of graphene assemblies in the liquid phase and thus can provide useful insights to the experimental design relating to restacking control. This work also reveals the huge effect some routine processing conditions, such as heat treatment and drying, can have on the structure and performance of graphene‐based bulk materials, providing useful guidance for future manufacturing of this class of materials.
Controlled Stacking and Unstacking of Peripheral Chlorophyll Units Drives the Spring‐Like Contraction and Expansion of a Semi‐Artificial Helical Polymer
Authors: Numata Munenori , Kinoshita Daiki , Hirose Naoya , Kozawa Tomohiro , Tamiaki Hitoshi , Kikkawa Yoshihiro , Kanesato Masatoshi
Published: January 2013

Developing new strategies for controlling polymer conformations through precise molecular recognition can potentially generate a machine‐like motion that is dependent on molecular information—an important process for the preparation of new intelligent nanomaterials (e.g., polymer‐based nanomachines) in the field bordering between polymer chemistry and conventional supramolecular sciences. Herein, we propose a strategy to endow a helical polymer chain with dynamic spring‐like (contraction/expansion) motion through the one‐dimensional self‐assembly (aggregation/disaggregation) of peripheral amphiphilic molecules. In this developing system, we employed a semi‐artificial helical polysaccharide presenting peripheral amphiphilic chlorophyll units as a power device that undergoes contractive motion in aqueous media, driven by strong π–π interactions of its chlorophyll units or by cooperative molecular recognition of bipyridyl‐type ligands through pairs of chlorophyll units, thereby converting molecular information into the regulated motion of a spring. In addition, this system also undergoes expansive motion through coordination of pyridine. We anticipate that this strategy will be applicable (when combined with the established wrapping chemistry of the helical polysaccharide) to the development of, for example, drug carriers (e.g., nano‐syringes), actuators (stimuli‐responsive films), and directional transporters (nano‐railways), thereby extending the frontiers of supramolecular science.
Fueling Open‐Source Drug Discovery: 177 Small‐Molecule Leads against Tuberculosis
Authors: Ballell Lluís , Bates Robert H. , Young Rob J. , Alvarez‐Gomez Daniel , Alvarez‐Ruiz Emilio , Barroso Vanessa , Blanco Delia , Crespo Benigno , Escribano Jaime , González Rubén , Lozano Sonia , Huss Sophie , Santos‐Villarejo Angel , Martín‐Plaza José Julio , Mendoza Alfonso , Rebollo‐Lopez María José , Remuiñan‐Blanco Modesto , Lavandera José Luis , Pérez‐Herran Esther , Gamo‐Benito Francisco Javier , García‐Bustos José Francisco , Barros David , Castro Julia P. , Cammack Nicholas
Published: January 2013

With the aim of fuelling open‐source, translational, early‐stage drug discovery activities, the results of the recently completed antimycobacterial phenotypic screening campaign against Mycobacterium bovis BCG with hit confirmation in M. tuberculosis H37Rv were made publicly accessible. A set of 177 potent non‐cytotoxic H37Rv hits was identified and will be made available to maximize the potential impact of the compounds toward a chemical genetics/proteomics exercise, while at the same time providing a plethora of potential starting points for new synthetic lead‐generation activities. Two additional drug‐discovery‐relevant datasets are included: a) a drug‐like property analysis reflecting the latest lead‐like guidelines and b) an early lead‐generation package of the most promising hits within the clusters identified.
Body mass index at diagnosis and survival among colon cancer patients enrolled in clinical trials of adjuvant chemotherapy
Authors: Sinicrope Frank A. , Foster Nathan R. , Yothers Greg , Benson Al , Seitz Jean Francois , Labianca Roberto , Goldberg Richard M. , DeGramont Aimery , O'Connell Michael J. , Sargent Daniel J. ,   for the Adjuvant Colon Cancer Endpoints (ACCENT) Group
Published: January 2013

BACKGROUND:

Although obesity is an established risk factor for developing colon cancer, its prognostic impact and relation to patient sex in colon cancer survivors remains unclear.

METHODS:

The authors examined the prognostic and predictive impact of the body mass index (BMI) in patients with stage II and III colon carcinoma (N = 25,291) within the Adjuvant Colon Cancer Endpoints (ACCENT) database. BMI was measured at enrollment in randomized trials of 5‐fluorouracil–based adjuvant chemotherapy. Association of BMI with the time to recurrence (TTR), disease‐free survival (DFS), and overall survival (OS) were determined using Cox regression models. Statistical tests were 2‐sided.

RESULTS:

During a median follow‐up of 7.8 years, obese and underweight patients had significantly poorer survival compared with overweight and normal‐weight patients. In a multivariable analysis, the adverse prognostic impact of BMI was observed among men but not among women (Pinteraction= .0129). Men with class 2 and 3 obesity (BMI ≥35.0 kg/m2) had a statistically significant reduction in DFS (hazard ratio [HR], 1.16; 95% confidence interval [CI], 1.01‐1.33;P= .0297) compared with normal‐weight patients. Underweight patients had a significantly shorter TTR and reduced DFS (HR, 1.18; 95% CI, 1.09‐1.28;P< .0001) that was more significant among men (HR, 1.31; 95% CI, 1.15‐1.50;P< .0001) than among women (HR, 1.11; 95% CI, 1.01‐1.23;P= .0362;Pinteraction= .0340). BMI was not predictive of a benefit from adjuvant treatment.

CONCLUSIONS:

Obesity and underweight status were associated independently with inferior outcomes in patients with colon cancer who received treatment in adjuvant chemotherapy trials. Cancer 2013. © 2013 American Cancer Society.
Efficient brain lesion segmentation using multi‐modality tissue‐based feature selection and support vector machines
Authors: Fiot Jean‐Baptiste , Cohen Laurent D. , Raniga Parnesh , Fripp Jurgen
Published: January 2013

Support vector machines (SVM) are machine learning techniques that have been used for segmentation and classification of medical images, including segmentation of white matter hyper‐intensities (WMH). Current approaches using SVM for WMH segmentation extract features from the brain and classify these followed by complex post‐processing steps to remove false positives. The method presented in this paper combines advanced pre‐processing, tissue‐based feature selection and SVM classification to obtain efficient and accurate WMH segmentation. Features from 125 patients, generated from up to four MR modalities [T1‐w, T2‐w, proton‐density and fluid attenuated inversion recovery(FLAIR)], differing neighbourhood sizes and the use of multi‐scale features were compared. We found that although using all four modalities gave the best overall classification (average Dice scores of 0.54  ±  0.12, 0.72  ±  0.06 and 0.82  ±  0.06 respectively for small, moderate and severe lesion loads); this was not significantly different (p = 0.50) from using just T1‐w and FLAIR sequences (Dice scores of 0.52  ±  0.13, 0.71  ±  0.08 and 0.81  ±  0.07). Furthermore, there was a negligible difference between using 5 × 5 × 5 and 3 × 3 × 3 features (p = 0.93). Finally, we show that careful consideration of features and pre‐processing techniques not only saves storage space and computation time but also leads to more efficient classification, which outperforms the one based on all features with post‐processing. Copyright © 2013 John Wiley & Sons, Ltd.
Low‐Temperature Sol‐Gel Synthesis of Nanostructured Polymer/Titania Hybrid Films based on Custom‐Made Poly(3‐Alkoxy Thiophene)
Authors: Niedermeier Martin A. , Rawolle Monika , Lellig Philipp , Körstgens Volker , Herzig Eva M. , Buffet Adeline , Roth Stephan V. , Gutmann Jochen S. , Fröschl Thomas , Hüsing Nicola , Müller‐Buschbaum Peter
Published: January 2013

A low‐temperature route to directly obtain polymer/titania hybrid films is presented. For this, a custom‐made poly(3‐alkoxy thiophene) was synthesized and used in a sol‐gel process together with an ethylene‐glycol‐modified titanate (EGMT) as a suitable titania precursor. The poly(3‐alkoxy thiophene) was designed to act as the structure‐directing agent for titanium dioxide through selective incorporation of the titania precursor. The nanostructured titania network, embedded in the polymer matrix, is examined with atomic force microscopy (AFM) and scanning electron microscopy (SEM) measurements. By means of the scattering technique grazing incidence wide‐angle X‐ray scattering (GIWAXS), a high degree of crystallinity of the polymer as well as successful transformation of the precursor into the rutile phase of titania is verified. UV/Vis measurements reveal an absorption behavior around 500 nm which is similar to poly(3‐hexyl thiophene), a commonly used polymer for photoelectronic applications, and in addition, the typical UV absorption behavior of rutile titania is observed.
Photophysics of Silicon Phthalocyanines in Aqueous Media
Authors: Doane Tennyson L. , Chuang Chi‐Hung , Chomas Andrew , Burda Clemens
Published: January 2013

Phthalocyanines have been used as photodynamic therapy (PDT) agents because of their uniquely favorable optical properties and high photostability. They have been shown to be highly successful for the treatment of cancer through efficient singlet‐oxygen (1O2) production. However, due to their hydrophobic properties, the considerations of solubility and cellular location have made understanding their photophysics in vitro and in vivo difficult. Indeed, many quantitative assessments of PDT reagents are undertaken in purely organic solvents, presenting challenges for interpreting observations during practical application in vivo. With steady‐state and time‐resolved laser spectroscopy, we show that for axial ligated silicon phthalocyanines in aqueous media, both the water:lipophile ratio and the pH have drastic effects on their photophysics, and ultimately dictate their functionality as PDT drugs. We suggest that considering the presented photophysics for PDT drugs in aqueous solutions leads to guidelines for a next generation of even more potent PDT agents.
Understanding Electronic Ligand Perturbation over Successive Metal‐Based Redox Potentials in Mononuclear Ruthenium–Aqua Complexes
Authors: Vaquer Lydia , Miró Pere , Sala Xavier , Bozoglian Fernando , Masllorens Ester , Benet‐Buchholz Jordi , Fontrodona Xavier , Parella Teodor , Romero Isabel , Roglans Anna , Rodríguez Montserrat , Bo Carles , Llobet Antoni
Published: January 2013

A family of new ruthenium complexes containing a combination of polypyridyl and carbene ligands has been prepared and characterized from structural, spectroscopic, and redox viewpoints both experimentally and computationally. Interestingly, a correlation between ΔE1/2, defined as the difference between E1/2(RuIV/III) and E1/2(RuIII/II), and the activity and selectivity of some catalytic oxidation processes has been clearly established. A density functional theory study on the synthesized species has been carried out revealing a correlation between the number of carbene ligands and ΔE1/2, and consequently with the RuIII disproportionation. The reactivity of these complexes has been tested with regard to the electrocatalytic oxidation of benzyl alcohol.
Comparison of the clinical effectiveness of different off‐loading devices for the treatment of neuropathic foot ulcers in patients with diabetes: a systematic review and meta‐analysis
Authors: Morona Judy K. , Buckley Elizabeth S. , Jones Sara , Reddin Edith A. , Merlin Tracy L.
Published: January 2013

Effective off‐loading is considered to be an important part of the successful clinical management of diabetic foot ulcers. The aim of this systematic review is to investigate the safety and effectiveness of different off‐loading devices for the treatment of diabetic foot ulcers. The medical literature was extensively searched from January 1966 to May 2012. Systematic reviews and controlled studies that compared the use of different off‐loading devices formed the evidence base. Studies were critically appraised to determine their risk of methodological bias, and data were extracted. Results were pooled using random effects meta‐analysis and tested for heterogeneity. When compared with removable devices, non‐removable off‐loading devices were found, on average, to be more effective at promoting the healing of diabetic foot ulcers (RRp = 1.43; 95% CI 1.11, 1.84;I2 = 66.9%;p = 0.001;k = 10). Analysis, stratified by type of removable device, did not detect a statistically significant difference between non‐removable off‐loading devices and removable cast walkers; however, on average non‐removable off‐loading devices performed better than therapeutic shoes at promoting the healing of diabetic foot ulcers (RRp = 1.68; 95% CI 1.09, 2.58;I2 = 71.5%;p = 0.004;k = 6). The two types of non‐removable off‐loading devices i.e. total contact casts and instant total contact casts (removable cast walker rendered irremovable by securing with bandage or lace), were found to be equally effective (RRp = 1.06; 95% CI 0.88, 1.27;I2 = 3.3%;p = 0.31;k = 2). In conclusion, non‐removable off‐loading devices regardless of type, are more likely to result in ulcer healing than removable off‐loading devices, presumably because patient compliance with off‐loading is facilitated. Copyright © 2013 John Wiley & Sons, Ltd.
Carbon isotope ratio mass spectrometry for detection of endogenous steroid use: A testing strategy
Authors: Ahrens Brian D. , Butch Anthony W.
Published: January 2013

Isotope ratio mass spectrometry (IRMS) testing is performed to determine if an atypical steroid profile is due to administration of an endogenous steroid. Androsterone (Andro) and etiocholanolone (Etio), and/or the androstanediols (5α‐ and 5β‐androstane‐3α,17β‐diol) are typically analyzed by IRMS to determine the13C/12C ratio. The ratios of these target compounds are compared to the13C/12C ratio of an endogenous reference compound (ERC) such as 5β‐pregnane‐3α,20α‐diol (Pdiol). Concentrations of Andro and Etio are high so13C/12C ratios can easily be measured in most urine samples. Despite the potentially improved sensitivity of the androstanediols for detecting the use of some testosterone formulations, additional processing steps are often required that increase labour costs and turnaround times. Since this can be problematic when performing large numbers of IRMS measurements, we established thresholds for Andro and Etio that can be used to determine the need for additional androstanediol testing. Using these criteria, 105 out of 2639 urine samples exceeded the Andro and/or Etio thresholds, with 52 of these samples being positive based on Andro and Etio IRMS testing alone. The remaining 53 urine samples had androstanediol IRMS testing performed and 3 samples were positive based on the androstanediol results. A similar strategy was used to establish a threshold for Pdiol to identify athletes with relatively13C‐depleted values so that an alternative ERC can be used to confirm or establish a true endogenous reference value. Adoption of a similar strategy by other laboratories can significantly reduce IRMS sample processing and analysis times, thereby increasing testing capacity. Copyright © 2013 John Wiley & Sons, Ltd.
Solvent‐Controlled Synthesis and Luminescence Properties of Uniform Eu:YVO4 Nanophosphors with Different Morphologies
Authors: Nuñez Nuria , Sabek Jad , García‐Sevillano Jorge , Cantelar Eugenio , Escudero Alberto , Ocaña Manuel
Published: January 2013

A facile solvothermal route has been developed for the preparation of tetragonal europium‐doped yttrium orthovanadate nanoparticles (Eu:YVO4) and is based on a homogeneous precipitation reaction at 120 °C from solutions of rare earth precursors (yttrium acetylacetonate and europium nitrate) and sodium orthovanadate in ethylene glycol or ethylene glycol/water mixtures. The nature of the solvent has a dramatic effect on the morphology and crystallinity of the resulting nanoparticles. Polycrystalline nanoellipsoids (130 × 60 nm) were obtained in pure ethylene glycol, whereas quasispherical nanoparticles (100 nm) with monocrystalline character precipitated in ethylene glycol/water (7:3 by volume) mixtures. To explain these different morphological and structural features, the mechanism of particles formation was investigated. The effects of the doping level on the luminescence properties (emission spectra and luminescence lifetime) were also evaluated to find the optimum nanophosphors. Finally, it is shown that the luminescent efficiency of the quasispherical nanoparticles was higher than that of the nanoellipsoids; this can be related to differences in crystallinity and in impurity content.
From Magnetic to Nonlinear Optical Switches in Spin‐Crossover Complexes
Authors: Lacroix Pascal G. , Malfant Isabelle , Real Jose‐Antonio , Rodriguez Vincent
Published: January 2013

Various attempts to combine magnetic and nonlinear optical (NLO) properties in a molecule are reviewed, with a special focus on the possibility of interplay between the magnetic component and the quadratic ([prop] E2) NLO response. This multidisciplinary research leads to the idea of spin‐crossover‐induced (SCO‐induced) NLO switching and is evaluated at the synthetic level, with insights provided by computational chemistry. The need for nontraditional experimental setups to record NLO properties in the solid state is discussed.
N‐Methyl‐4,4′‐bipyridinium and N‐Methyl‐N′‐oxide‐4,4′‐bipyridinium Bismuth Complexes – Photochromism and Photoluminescence in the Solid State
Authors: Toma Oksana , Mercier Nicolas , Botta Chiara
Published: January 2013

Three bismuth complexes based on N‐methyl‐4,4′‐bipyridinium (hMV+), (hMV)[Bi(hMV)Cl5] (1), and N‐methyl‐N′‐oxide‐4,4′‐bipyridinium (MVO+), [Bi(MVO)X4(dmso)]·dmso [X = Cl (2), Br (3)], are reported. All three compounds show luminescence in the solid state with maxima at 545 nm (yellow for 1) and 560 nm (orange for 2 and 3) with quantum yields up to 10 %. Upon UV irradiation, 1 undergoes a color change from white to blue accompanied by a reduction of the photoluminescence intensity. The analysis of the crystal structure of the three complexes points to a photoinduced charge‐transfer (PICT) process at the origin of the photochromism in 1.
The Effects of Ring Expansion and N‐Methylation on the Complexation Behaviour of Macrodinucleating Hexaaza‐Dithiophenolate Macrocycles: Destabilization of the CoIII Oxidation Level and Lowering of the Coordination Number
Authors: Lehmann Ulrike , Lach Jochen , Schleife Frederik , Jeremies Alexander , Kersting Berthold
Published: January 2013

The preparation and characterization of 30‐membered hexaza‐dithiophenolate macrocycles H2L4–H2L6 with different degrees and patterns of N‐alkylation and their complexation properties towards cobalt are reported. Three dinuclear {[CoIII2(L4)(µ‐OH)]3+ (3), [CoIIICoII(L5)(µ‐OH)]2+ (4), [CoII2H2(L6)Cl2]2+ (5)} and one mononuclear complex {[CoII(L6)]2+ (6)} were obtained, isolated as ClO4– or BPh4– salts, and characterized by CHN analysis, ESI mass spetrometry, IR, UV/Vis, and NMR spectroscopy, cyclic voltammetry, magnetic susceptibility measurements (for 4–6), and X‐ray crystallography (3–6). In contrast to parent N6S2 macrocycles with diethylenetriamine linkers, which support only face‐sharing bioctahedral [Co2L(L′)]n+ complexes (L′ = bridging coligand), the new macrocycles show greater structural diversity enabling the formation of triply bridged complexes with octahedral CoIII,IIN3S2O (3, 4), non‐bridged dinuclear complexes with tetrahedral CoIIN2SCl (5), and mononuclear complexes with square‐pyramidal CoIIN3S2 (6) coordination environments. The increasing stability of the CoII oxidation level across this series of complexes is a consequence of the increasing degree of N‐alkylation coupled with a decreasing ligand‐field strength of the tertiary amine functions, as demonstrated by significant anodic shifts in the cyclic voltammograms of 3 and 4. The effective magnetic moments of the CoII ions in 4, 5, and 6 (4.67–5.23 µB) are significantly higher than the expected spin‐only value of 3.87 µB, indicative of an orbital contribution to the magnetic moment.
A Concise and Efficient Synthesis of Spiroketals – Application to the Synthesis of SPIKET‐P and a Spiroketal from Bactrocera Species
Authors: Tomas Loic , Bourdon Benjamin , Caille Jean Claude , Gueyrard David , Goekjian Peter G.
Published: January 2013

We report the synthesis of spiroketals by sequence of enol ether synthesis and cyclization. The enol ethers were prepared from lactones by a Julia olefination reaction, and the starting chiral lactone was prepared from an industrial intermediate. This route is a concise and efficient way to synthesize naturally occurring and biologically interesting spiroketals. We used this sequence for the preparation of SPIKET‐P and a spiroketal from Bactrocera species.
Study of Bare and Mercury‐Coated Vibrated Carbon, Gold and Silver Microwire Electrodes for the Determination of Lead and Cadmium in Seawater by Anodic Stripping Voltammetry
Authors: Bi Zhaoshun , Salaün Pascal , van den Berg Constant M. G.
Published: January 2013

Carbon, gold and silver microwires are revisited under vibrated conditions for detection of trace lead and cadmium in seawater. The Pb and Cd peaks fully overlapped on the bare gold and carbon electrodes and partially on the silver electrode. The sensitivity of all three was insufficient for detection in uncontaminated waters. Peak separation was obtained after coating with mercury (Hg). Only the Hg‐coated silver electrode is suitable when preplated. Limits of detection for Pb using the Hg/C and Hg/Ag electrodes (20–40 pM), and Cd (70 pM), are sufficiently low for Pb and Cd detection in seawater.
Voltammetric Determination of Boric Acid Using the Ternary Complexation System with Salicylaldehyde and H‐Acid
Authors: Takehara Kô , Fujimori Takao , Inagi Kei , Kajiwara Mari , Harata Yoshikazu , Yoshimura Kazuhisa
Published: January 2013

A square‐wave voltammetric method for the determination of boric acid in water has been described based on the new understanding of the electrochemical behavior of boric acid‐Azomethine H complexation. Salicylaldehyde and H‐acid were used as the starting materials of boric acid‐Azomethine H complex and their concentrations were optimized for boric acid determination in water. A glassy carbon electrode, instead of a conventional mercury electrode, was used in the measurement. The detection limit of the proposed method was 0.10 mg B dm−3. The proposed method was successfully used for boric acid determination in the water from a seawater desalination RO plant.
Effects of SiO2/Na2O molar ratio on properties of TFT‐LCD waste glass‐metakaolin‐based geopolymers
Authors: Lin Kae‐Long , Shiu Hau‐Shing , Hwang Chao‐Lung , Cheng An , Cheng Ta‐Wui
Published: January 2013

Only 69% of thin‐film transistor liquid crystal display (TFT‐LCD) waste glass is reused in Taiwan. More reuse methods must be developed to increase this percentage. TFT‐LCD waste glass mostly contains SiO2 and Al2O3, which are raw materials used in the production of geopolymer. This study examines the effect of the SiO2/Na2O ratio (0.8–2.0) and the replacement of 0–40% TFT‐LCD waste glass on the properties of waste glass‐metakaolin‐based geopolymer. The samples underwent a series of tests to determine their quality, including their setting time, compressive strength, and thermal conductivity. The results showed that the compressive strength increased with curing time, and that the products of geopolymerization filled the pores, causing the thermal conductivity to increase with curing time. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 205–212, 2014
Certificate‐based verifiably encrypted RSA signatures
Authors: Shao Zuhua , Gao Yipeng
Published: January 2013

The RSA signature scheme is one of the most popular signature schemes to date. This paper proposes a certificate‐based verifiably encrypted RSA signature scheme that is the first to accomplish optimistic fair exchange of the standard RSA signatures. The main characteristic of this scheme is that the signer can unilaterally choose a certificate authority as his/her adjudicator in fair exchange. Then a certificate, or generally, a signature, acts not only as the binding of the public key and its holder but also as the certificate authority's guarantee against partiality in adjudication. We introduce a strong security model, in which there are three types of inside adversaries with more power than outside adversaries in previous verifiably encrypted RSA signature schemes. We then show that the proposed scheme is existentially unforgeable under the Discrete Logarithm (DL) assumption, the Computational Diffile‐Dellman (CDH) assumption, and the RSA assumption in the random oracle model. Because the proposed scheme can be directly used in the current Public‐Key Infrastructure (PKI) environment, it is more practical and trustworthy than the previous schemes in the real world. Copyright © 2013 John Wiley & Sons, Ltd.
Effects of temperature on type approval testing of ballast water treatment systems
Authors: Drillet Guillaume , Schmoker Claire , Trottet Aurore , Mahjoub Mohamed-Sofiane , Duchemin Matthieu , Andersen Martin
Published: January 2013

To limit the risk associated with invasion of habitats by exogenous species, the International Convention for the Control and Management of the Ships' Ballast Water and Sediments was adopted in February 2004 and may soon enter into force. The International Maritime Organization (IMO) has produced guidelines to assess the efficacy and reliability of Ballast Water Treatment Systems (BWTS), but no guidance on how to take temperature into account during test cycles has been provided yet. Temperature is one of the main factors influencing the distribution and ecology of organisms along latitudes. Its increase results in higher grazing, growth, and reproduction rates of zooplankton. Under dark conditions, phytoplankton loss is also increased due to faster natural decay as well as enhanced top down control from zooplankton. Increased temperatures also improve the efficacy of chemical treatment, whereas the decay rates of disinfectants and their byproducts are potentially accelerated. The IMO guidelines for the type approval of BWTS should be amended to include recommendations on how to take temperature into account. Failing to ensure comparability and reliability between tests may pose a threat to the environment and may create problems for those attempting to apply BWTS. We propose to use a fixed Q10 value and a temperature of reference to adjust the retention time in ballast water tanks during testing. Integr Environ Assess Manag 2013; 9: 192–195. © 2013 SETAC
Effects of the Early Prevention Program “Keiner FÄllt Durchs Netz” (“Nobody Slips Through the Net”) on Child, Mother, and Their Relationship: A Controlled Study
Authors: Sidor Anna , Kunz Elisabeth , Eickhorst Andreas , Cierpka Manfred
Published: January 2013

The study investigated the effects of a German family‐supporting prevention program “Keiner fällt durchs Netz” (KfdN; “Nobody Slips Through the Net”) after the child's first year in the sample of 152 psychosocially stressed mothers and children who took part in this program and 150 mothers and children from comparison‐group families. The improved level of development posited in the children after intervention as compared to children from the comparison group was confirmed in the social development area (d = .35). In addition, mothers in the KfdN group judged their 1‐year‐old children to be less “difficult” compared to the assessments of the mothers in the comparison group (d = .24). Due to the intervention, the dysfunctionality of the mother–child interaction was reduced (mothers’ self‐assessment, d = .27). No intervention effects were found in for degree of maternal stress. The expected intervention effects in maternal sensitivity were not empirically confirmed. The results suggest that the KfdN intervention exerted a direct positive influence on childhood traits such as social development and temperamental “difficulty” and also positively influenced the mothers’ perceptions or attitudes toward their children's conduct.
Sleep and Attachment in Preterm Infants
Authors: Schwichtenberg A.J. , Shah Prachi E. , Poehlmann Julie
Published: January 2013

Infants born preterm are at elevated risk for socioemotional difficulties; however, factors contributing to this risk are largely understudied. Within the present study, we explored infant sleep as a biosocial factor that may play a role in infant socioemotional development. Within a prospective longitudinal design, we examined parent‐reported sleep patterns and observed parenting quality as predictors of infant–mother attachment in 171 infants born preterm. Using structural equation modeling, we examined main effect and moderator models linking infant sleep patterns and parenting with attachment security. Sleep patterns characterized by more daytime sleep and positive/responsive parenting predicted infant attachment security. Parent‐reported nighttime sleep patterns were unrelated to attachment in this sample of infants born preterm. These results indicate that daytime sleep and parenting quality may be important for emerging attachment relationships in infants born preterm.
Satisfaction and Stressors in a Religious Minority: A National Study of Orthodox Jewish Marriage
Authors: Schnall Eliezer , Pelcovitz David , Fox Debbie
Published: January 2013

The paucity of mental health studies with Orthodox Jews makes culturally competent counseling care unlikely. In this large‐scale investigation of marriage among Orthodox Jews, most respondents reported satisfaction with marriage and spouse, although satisfaction was highest among recently married couples. The most significant stressors were finances, communication, physical intimacy/sexuality, time pressures, and in‐law conflicts. Counseling interventions are discussed.

La escasez de estudios sobre salud mental en poblaciones de judíos ortodoxos limita la posibilidad de ofrecer un cuidado de consejería culturalmente competente. En esta investigación a gran escala sobre el matrimonio entre judíos ortodoxos, la mayoría de los participantes indicaron satisfacción con su matrimonio y esposo/a, aunque la satisfacción fue mayor entre las parejas recién casadas. Los elementos estresantes más significativos fueron las finanzas, la comunicación, el contacto íntimo/sexualidad, la falta de tiempo, y los conflictos con la familia política. Se discuten intervenciones para la consejería.
Feasibility of capillary velocity assessment by statistical means using dual‐beam spectral‐domain Optical Coherence Tomography: a preliminary study
Authors: Daly Susan M. , Silien Christophe , Leahy Martin J.
Published: January 2013

The assessment of vascular dynamics has been shown to yield both qualitative and quantitative metrics and thus play a pivotal role in the diagnosis and prognosis of various diseases, which may manifest as microcirculatory irregularities. Optical Coherence Tomography (OCT) is an established imaging modality which utilises the principle of optical interferometry to distinguish between spatial changes in refractive index and thus formulate a multi‐dimensional representation of a specimen in vivo. Nonetheless, difficulties remain in obtaining accurate data (morphological and/or transient) in an environment which is subject to such large biological variability. In an effort to address the issue of angular dependence as with Doppler based analysis, a dual‐beam Spectral‐domain OCT system for quasi‐simultaneous specimen scanning is described. A statistical based method of phase correlation is outlined which is capable of quantifying velocity values in addition to the ability to discern bidirectionality, without the necessity of angular computation. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Assessing Depression in Rural Communities
Authors: Brossart Daniel F. , Wendel Monica L. , Elliott Timothy R. , Cook Helene E. , Castillo Linda G. , Burdine James N.
Published: January 2013

Objectives

Examined the severity of depressive symptoms and the rates of probable depression assessed by different instruments that were included in two separate surveys of residents in a predominately rural region of the United States.

Method

Surveys of the Brazos Valley region in south central Texas were conducted and responses to the short form of the Center for Epidemiological Studies‐Depression scale (in the 2006 survey) and the Patient Health Questionnaire‐9 (in the 2010 survey) were analyzed.

Results

Regardless of instrument used, results indicate that women and African Americans are at greater risk for depression in this underserved region, but no unique effects were found for rural residency.

Implications

Implications for research, assessment, program planning, and policy are discussed.
Photooxidation of glycated and non‐glycated phosphatidylethanolamines monitored by mass spectrometry
Authors: Melo Tânia , Silva Eduarda M. P. , Simões Cláudia , Domingues Pedro , Domingues M. Rosário M.
Published: January 2013

Phosphatidylethanolamines (PE) are one of the major components of cells membranes, namely in skin and in retina, that are continuously exposed to solar UV radiation being major targets of photooxidation damage. In addition, due to the presence of the free amine group, PE can also undergo glycation, in hyperglycemic conditions which may increase the susceptibility to oxidation. The aim of this study is to develop a model, based on mass spectrometry (MS) analysis, to identify photooxidative degradation of selected PE (POPE: PE 16:0/18:1, PLPE: PE 16:0/18:2, PAPE: PE 16:0/20:4) and glycated PEs due to UV irradiation. Photooxidation products were analysed by electrospray ionization MS (ESI‐MS) and tandem MS (ESI‐MS/MS) in positive and negative mode. Emphasis is placed in the influence of glycation in the generation of distinct photooxidation products. ESI‐MS spectra of PE after UV photo‐irradiation showed mainly hydroperoxy derivatives, due to oxidation of unsaturated fatty acyl chains. Glycated PE gave rise to several new photooxidation products formed due to oxidative cleavages of the glucose moiety, namely between C1 and C2, C2 and C3, and C5 and C6 of this sugar unit. These new products were identified by ESI‐MS/MS in positive mode showing distinct neutral loss depending on the different structure of the polar head group. These new identified advanced glycated photooxidation products may have a deleterious role in the etiology of diabetic retinopathy and in diabetic retinal microvascular complications. Copyright © 2013 John Wiley & Sons, Ltd.
When mentors feel supported: Relationships with mentoring functions and protégés' perceived organizational support
Authors: Hu Changya , Wang Sheng , Yang Chun‐Chi , Wu Tsung‐yu
Published: January 2013

We surveyed full‐time employees of ongoing mentoring relationships to investigate relationships among mentors' perceived organizational support (POS), the extent of mentoring functions protégés received, and protégés' POS. Moreover, we examined the moderating role of mentors' altruistic personality in the relationship between mentors' POS and mentoring functions received. Results showed that mentors' POS was positively related to the extent of mentoring protégés reported receiving, which was then related positively to protégés' POS. Furthermore, the extent of mentoring received partially mediated the relationship between mentors' POS and protégés' POS. We also found that mentors' altruistic personality moderated the positive relationship between mentors' POS and the extent of mentoring received such that this relationship was stronger for low altruistic mentors. Theoretical and practical implications of the findings are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of adsorption mode of new B2 bradykinin receptor antagonists onto colloidal Ag substrate
Authors: Sobolewski Dariusz , Proniewicz Edyta , Skołuba Dominika , Prahl Adam , Ozaki Yukihiro , Kim Younkyoo , Proniewicz Leonard M.
Published: January 2013

In this paper, the surface‐enhanced Raman scattering (SERS) spectra of the potent B2 bradykinin receptor antagonists, [D‐Arg0,Hyp3,Thi5,8,L‐Pip7]BK, Aaa[D‐Arg0,Hyp3,Thi5,8,L‐Pip7]BK, [D‐Arg0,Hyp3,Thi5,D‐Phe7,L‐Pip8]BK, and Aaa[D‐Arg0,Hyp3,Thi5,D‐Phe7,L‐Pip8]BK, were measured when immobilized onto a colloidal assembly of apparently randomly adhering Ag spheres with diameters of approximately 20 – 25 nm. The observed SERS bands corresponding to different vibrational modes of the molecule, attached to or near Ag, and the variations in these bands resulting from competitive interactions of the functional groups of the peptides with the SERS‐active Ag surfaces were analyzed in this study. Briefly, it was shown that Pip, in generally in vertical orientation, and Thi, in the edge‐on position, relative to the colloidal Ag surface interacted with this surface through their lone electron pairs on the nitrogen and sulfur atoms, respectively. The imide bond of the X‐Pro peptide linkage and the guanidine group of Arg were involved in the adsorption process. In addition, it was demonstrated that the specific differences in the amino acid sequences slightly influenced the mode of adsorption. For example, Aaa in Aaa[D‐Arg0,Hyp3,Thi5,8,L‐Pip7]BK and Aaa[D‐Arg0,Hyp3,Thi5,D‐Phe7,L‐Pip8]BK and D‐Phe (vertical with respect to the colloidal Ag surface) in [D‐Arg0,Hyp3,Thi5,D‐Phe7,L‐Pip8]BK, and Aaa[D‐Arg0,Hyp3,Thi5,D‐Phe7,L‐Pip8]BK assisted in the adsorption of these peptides onto the colloidal Ag particles. To discuss these spectral alterations due to the different surface adsorption mechanisms of these peptides, the spectral changes were analyzed according to the adsorption process and Fourier‐transform‐Raman spectra. Copyright © 2013 John Wiley & Sons, Ltd.
Perennial peanut (Arachisglabrata Benth.) contains polyphenol oxidase (PPO) and PPO substrates that can reduce post‐harvest proteolysis
Authors: Sullivan Michael L , Foster Jamie L
Published: January 2013

Background

Studies of perennial peanut (Arachis glabrata Benth.) suggest its hay and haylage have greater levels of rumen undegraded protein (RUP) than other legume forages such as alfalfa (Medicago sativa L.). Greater RUP can result in more efficient nitrogen utilization by ruminant animals with positive economic and environmental effects. We sought to determine whether, like red clover (Trifolium pretense L.), perennial peanut contains polyphenol oxidase (PPO) and PPO substrates that might be responsible for increased RUP.

Results

Perennial peanut extracts contain immunologically detectible PPO protein and high levels of PPO activity (>100 nkatal mg−1 protein). Addition of caffeic acid (PPO substrate) to perennial peanut extracts depleted of endogenous substrates reduced proteolysis by 90%. Addition of phenolics prepared from perennial peanut leaves to extracts of either transgenic PPO‐expressing or control (non‐expressing) alfalfa showed peanut phenolics could reduce proteolysis >70% in a PPO‐dependent manner. Two abundant likely PPO substrates are present in perennial peanut leaves including caftaric acid.

Conclusions

Perennial peanut contains PPO and PPO substrates that together are capable of inhibiting post‐harvest proteolysis, suggesting a possible mechanism for increased RUP in this forage. Research related to optimizing the PPO system in other forage crops will likely be applicable to perennial peanut. Published 2013. This article is a U.S. Government work and is in the public domain in the USA