bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Subjective Response and Acquired Tolerance as Predictors of Alcohol Use and Related Problems in a Clinical Sample
Authors: Corbin William R. , Scott Caitlin , Leeman Robert F. , Fucito Lisa M. , Toll Benjamin A. , O'Malley Stephanie S.
Published: January 2013

Background

Previous studies have demonstrated that a low subjective response (SR) to alcohol is a risk factor for alcohol use disorders (AUDs), and a recent study suggests that acquired tolerance can be differentiated from initial SR and is also significantly associated with drinking problems. Because the prior study of SR and tolerance focused on a sample of moderate drinkers, the goal of the current study was to examine relations between early SR, acquired tolerance, alcohol use, and alcohol‐related problems in a sample of young adults with clinically significant alcohol problems.

Methods

The current study examined associations between early SR and acquired tolerance and both drinking behavior and alcohol‐related problems within a sample of 113 heavy drinking young adults (66.1% male) volunteering for a clinical trial of naltrexone in combination with brief motivational counseling.

Results

Consistent with the 1 prior study examining simultaneous effects of early SR and tolerance, both early SR and acquired tolerance were positively associated with typical drinking behavior, although tolerance was a much stronger predictor within this clinical sample. In contrast to the prior study, early SR was inversely associated with risk for alcohol‐related problems, and tolerance was not a significant predictor of problems.

Conclusions

The results suggested that, controlling for weekly drinking, a low early SR protected against acute negative consequences within a sample of heavy drinkers who had acquired significant tolerance to alcohol effects. It is possible that this protective effect may eventually shift to a risk factor by allowing individuals with a low SR to persist in a pattern of hazardous drinking.
The Effect of Transglutaminase on Rheology and Texture of Fermented Milk Products
Authors: Iličić Mirela D. , Milanović Spasenija D. , Carić Marijana Ð. , Vukić Vladimir R. , Kanurić Katarina G. , Ranogajec Marjan I. , Hrnjez Dajana V.
Published: January 2013

The aim of this study was to investigate the effect of transglutaminase (TG) addition on rheological properties, textural characteristics and microstructure of fermented milk products manufactured by different starters (probiotics and kombucha inoculum). Rheological analysis revealed that all manufactured fermented milk products had higher storage modulus than loss modulus and exhibited thixotropic and a typical shear thinning behavior. The addition of TG in milk increased approximately 10.5% hysteresis loop area, 39% firmness and 48% consistency in sample produced with probiotic starter and had more firm and stable gel structure than kombucha fermented milk products. The scanning electron microscopy micrographs showed that casein matrix of fermented milk products containing TG is continuous and uninterrupted except for void spaces occupied by milk serum and starter culture cell.

Practical Applications

Transglutaminase (TG) is a transferase that forms inter‐ and intramolecular isopeptide bounds in and between many proteins by cross‐linking of the amino acid residues of protein‐bound glutamine and lysine. Among the dairy proteins, the casein fraction represents a favorable substrate for TG, mainly due to the highly accessible and flexible open chain structure. Heat treatment prior to cross‐linking is necessary because the reactivity of TG is very low in unheated or pasteurized milk, despite the high reactivity of the casein. In the case of low‐fat products, behavior of milk proteins during the gelation process is of particular importance. Cross‐linking of preheated milk with reduced fat content results in improved gel firmness and reduced syneresis of acid‐induced milk protein gels. Also, TG treatment at optimal technological parameters, pH value and temperature of milk, can solve these problems in kombucha fermented milk products, improving firmness, consistency and viscosity of gel.
Lessons Learned
Authors: Caughie Pamela L.
Published: January 2013

Debates such as the one taken up here on the future of women’s literature in modernist studies define the peculiar temporality of feminism. The temporality of feminism, it seems, is consumed by frequently recurring moments of questioning its current relevance. Detailing various positions on the question of the place of women’s writing in the new modernist studies, these seven essays model again and again strategies for feminist modernist scholarship. Insofar as this cluster of essays provides numerous examples of how feminist work is being carried out in modernist studies today, this debate confirms that the end of feminism seems always to be anticipated too soon.
1,25‐dihydroxyvitamin D3 and its nuclear receptor repress human α1(I) collagen expression and type I collagen formation
Authors: Potter James J. , Liu Xiaopu , Koteish Ayman , Mezey Esteban
Published: January 2013

Background

Vitamin D deficiency is common in chronic liver disease particularly in those with severe liver fibrosis.

Aims

To determine the effect of 1,25‐dihydroxyvitamin D3 (1,25‐(OH)2D3) on the human α1(I) collagen promoter and collagen formation by human stellate LX‐2 cells and the mechanism of the effect of the vitamin D receptor (VDR) on the promoter.

Methods

Type I collagen was assessed by measurements of collagen mRNA and collagen protein and by transfection experiments. Binding of VDR to the α1(I) collagen promoter was determined by EMSA and ChIP assays.

Results

1,25‐(OH)2D3 decreased human α1(I) collagen mRNA and protein and the secretion of type I collagen by stellate cells after exposure to TGFβ1. Furthermore, 1,25‐(OH)2D3 inhibited TGFβ1–induced activation of the α1(I) collagen promoter in transfected LX‐2 cells. The effect of 1,25‐(OH)2D3 is mediated by the VDR, which binds at a proximal Sp1 site and also at a newly identified distal site on the collagen promoter. A VDR expression vector reduced the activities of the collagen promoter in transfected LX‐2 cells.

Conclusions

1,25‐(OH)2D3 inhibits type I collagen formation in human stellate cells. The effect of 1,25‐(OH)2D3 is mediated by its receptor which binds at a proximal Sp1.1 site and at a newly identified distal site on the collagen promoter. Correction of vitamin D deficiency in patients with chronic liver disease is a potential therapy to inhibit progression of fibrosis.
Whole-Genome Shotgun Sequence of Pseudomonas viridiflava, a Bacterium Species Pathogenic to Arabidopsis thaliana
Authors: Lefort Francois , Calmin Gautier , Crovadore Julien , Osteras Magne , Farinelli Laurent
Published: January 2013

We report here the first whole-genome shotgun sequence of
Pseudomonas viridiflava
strain UASWS38, a bacterium species pathogenic to the biological model plant
Arabidopsis thaliana
but also usable as a biological control agent and thus of great scientific interest for understanding the genetics of plant-microbe interactions.
Successful treatment of resistant SAPHO syndrome with anti-TNF therapy
Authors: Hampton Shayma Lamya , Youssef Hazem
Published: January 2013

A 42-year-old Caucasian woman with SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) refractory to non-steroidal anti-inflammatory drugs, sulfasalzine, methotrexate, bisphosphonates and steroids was successfully treated with antitumour necrosis factor therapy (infliximab). This case was a diagnostic challenge leading to extensive investigations for infection and malignancy and delayed diagnosis for several years. We report the significant improvement in clinical, radiological and laboratory markers of disease activity on infliximab and the steroid sparing effect of such therapy.
Critical incident reporting in emergency medicine: results of the prehospital reports
Authors: Hohenstein Christian , Hempel Dorothea , Schultheis Kerstin , Lotter Oliver , Fleischmann Thomas
Published: January 2013

Background

Medical errors frequently contribute to morbidity and mortality. Prehospital emergency medicine is prone to incidents that can lead to immediate deadly consequences. Critical incident reporting can identify typical problems and be the basis for structured risk management in order to reduce and mitigate these incidents.

Methods

We set up a free access internet website for German-speaking countries, with an anonymous reporting system for emergency medical services personnel. After a 7-year study period, an expert team analysed and classified the incidents into staff related, equipment related, organisation and tactics, or other.

Results

845 reports were entered in the study period. Physicians reported 44% of incidents, paramedics 42%. Most patients were in a life-threatening or potentially life-threatening situation (82%), and only 53% of all incidents had no influence on the outcome of the patient. Staff-related problems were responsible for 56% of the incidents, when it came to harm, 78% of these incidents were staff related.

Conclusions

Incident reporting in prehospital emergency medicine can identify system weaknesses. Most of the incidents were reported during care of patients in life-threatening conditions with a high impact on patient outcome. Staff-related problems contributed to the most frequent and most severe incidents.
Epilepsy in Asia: A Cambodian Experience
Authors: Bhalla Devender , Samleng Chan , Gérard Daniel , Oum Sophal , Druet-Cabanac Michel , Preux Pierre-Marie
Published: January 2013

Epilepsy is particularly challenging for resource-poor countries and in turn for Asia which is likely to have greater challenges in terms of treatment cost and deficit, premature mortality, health transitions, population and poverty size, etc. Here we present an example of working in one of the resource-poor ‘least-talked-about’ populations to demonstrate that finding financial means and achieving cross-country cooperation over a long period of time is possible even in countries with currently limited resources. Conducting such cooperation could be a model for other initiatives. Scientific, capacity-building, and political tools should be employed to generate local representative data and influence government policies. These measures can be of immediate benefit for patients in these countries.
Predicting Age of Onset in Familial Essential Tremor: How Much Does Age of Onset Run in Families
Authors: Louis Elan D. , Hernandez Nora , Rabinowitz Daniel , Ottman Ruth , Clark Lorraine N.
Published: January 2013

Background: The extent to which age of onset of essential tremor (ET) aggregates in families is unknown; hence, it is unclear whether information about the age of onset in one family member can be used to predict the age of onset in others. Methods: ET probands and relatives were enrolled in a genetic study at Columbia University. Results: Data from 26 probands and 52 relatives were analyzed. The probands’ age of onset correlated significantly with their relatives’ age of onset (r = 0.50, p = 0.001). In 57.7% of cases, the relative’s age of onset was within 10 years of the proband’s onset (i.e. a 20-year age range). The proportion of affected relatives with age at onset <20 years was 64.7% in the families of probands with onset younger than 20 years, but only 7.7% in the families of probands with onset ≥20 years (p < 0.001). There was little evidence for genetic anticipation; 9/18 (50.0%) children reported a younger age of onset than the proband. Conclusions: In families containing multiple individuals with ET, the age at onset of probands and relatives was significantly correlated. Age of onset may be most tightly linked in families in which the proband had a young age of onset.
Bursaphelenchus koreanus sp. n. (Nematoda: Parasitaphelenchidae) in packaging wood from South Korea
Authors: Gu Jianfeng , Wang Jiangling , Chen Xianfeng
Published: January 2013

Bursaphelenchus koreanus sp. n., isolated in Ningbo, P.R. China, from packaging wood made from Pinus sp. imported from South Korea, is described. It is characterised by a slim body (a = 28-35), lateral field with four lines, excretory pore located at level of, or slightly posterior to, median bulb, vulva at 75% of total body length, presence of a distinct vulval flap in lateral view, post-uterine branch extending for ca two-thirds of vulva-anus distance, female tail conical and ventrally bent with slightly pointed, irregular or roughened terminus (c′ = 4.1), spicules large and arcuate (27-34 μm) with pointed rostrum, cucullus visible but sometimes reduced to a small blunt extension. The new species belongs to the xylophilus group and is most similar to B. luxuriosae and B. paraluxuriosae. It is distinguished from other Bursaphelenchus species by morphology, ITS-RFLP patterns and sequencing results.
L'algèbre de Hopf et le groupe de Galois motiviques d'un corps de caractéristique nulle, I
Authors: Ayoub Joseph
Published: January 2013

C'est le premier volet d'une série de deux articles visant
à construire et étudier des groupes de Galois motiviques
dans le cadre des motifs triangulés.
On développe d'abord un formalisme général permettant d'associer à un foncteur monoïdal f, satisfaisant à certaines conditions naturelles, une algèbre de Hopf dans la catégorie monoïdale but de f. Ce formalisme sera ensuite appliqué à la réalisation de Betti des motifs de Morel–Voevodsky sur un corps de base k muni d'un plongement complexe

σ
:
k
↪
ℂ

$\sigma :k\hookrightarrow \mathbb {C}$

. On obtient ainsi une algèbre de Hopf

ℋ

m
o
t

(
k
,
σ
)

$\mathcal {H}_{\textup {mot}}(k,\sigma )$

de la catégorie dérivée des ℚ-espaces vectoriels. En utilisant le théorème de comparaison entre cohomologie singulière et cohomologie de De Rham, on obtient une description explicite de l'algèbre unitaire

ℋ

m
o
t

(
k
,
σ
)

⊗
ℂ

$\mathcal {H}_{\textup {mot}}(k,\sigma )\otimes \mathbb {C}$

montrant en particulier que le complexe

ℋ

m
o
t

(
k
,
σ
)

$\mathcal {H}_{\textup {mot}}(k,\sigma )$

n'a pas d'homologie en degrés strictement négatifs. On en déduit une structure de ℚ-algèbre de Hopf sur le 0-ième groupe d'homologie de

ℋ

m
o
t

(
k
,
σ
)

$\mathcal {H}_{\textup {mot}}(k,\sigma )$

dont le
spectre sera baptisé le groupe de Galois motivique.
Crystal structure of aqua-bis-1,10-phenanthroline-tetrafluorophthlatonickel( II)sesquihydrate, [Ni(C8F4O4)(C12H8N2)2)(H2O)](H2O)1.5, C32H21F4N4NiO6.5
Authors: Liu Yuan-Ying , Guo Jin-Fu , Li Hui-Yun , Zhao Guo-Yan
Published: January 2013

C32H21F4N4NiO6.5, monoclinic, C2/c (no. 15), a = 16.201(3) Å, b = 14.831(3) Å, c = 25.798(5) Å, β = 105.16(3)°, V = 5983.0 Å3, Z = 8, Rgt(F) = 0.0363, wRref(F2) = 0.0891, T = 293 K.
Disruption of the Cereblon Gene Enhances Hepatic AMPK Activity and Prevents High-Fat Diet–Induced Obesity and Insulin Resistance in Mice
Authors: Lee Kwang Min , Yang Seung-Joo , Kim Yong Deuk , Choi Yoo Duk , Nam Jong Hee , Choi Cheol Soo , Choi Hueng-Sik , Park Chul-Seung
Published: January 2013

A nonsense mutation in cereblon (CRBN) causes a mild type of mental retardation in humans. An earlier study showed that CRBN negatively regulates the functional activity of AMP-activated protein kinase (AMPK) in vitro by binding directly to the α1-subunit of the AMPK complex. However, the in vivo role of CRBN was not studied. For elucidation of the physiological functions of Crbn, a mouse strain was generated in which the Crbn gene was deleted throughout the whole body. In Crbn-deficient mice fed a normal diet, AMPK in the liver showed hyperphosphorylation, which indicated the constitutive activation of AMPK. Since Crbn-deficient mice showed significantly less weight gain when fed a high-fat diet and their insulin sensitivity was considerably improved, the functions of Crbn in the liver were primarily investigated. These results provide the first in vivo evidence that Crbn is a negative modulator of AMPK, which suggests that Crbn may be a potential target for metabolic disorders of the liver.
Thrombotic Thrombocytopenic Purpura in a Patient with Interferon Treated Hepatitis C Successfully Treated with Rituximab
Authors: Poddar Nishant , Wang Jen C.
Published: January 2013

Thrombotic thrombocytopenic purpura (TTP) is a life threatening condition associated with formation of platelet thrombi. Deficiency of ADAM TS 13 with presence of inhibitory anti-ADAM TS 13 Immunoglobulin G antibody is seen in patients with acquired TTP. TTP in patients on interferon therapy for chronic hepatitis C has rarely been reported. Furthermore, successful treatment of an initial episode of acute refractory acquired TTP, in a patient of chronic hepatitis C during interferon therapy with Rituximab, has not been previously reported. Here we describe a case of acute refractory acquired TTP associated with pegylated interferon therapy for her chronic hepatitis C infection. Initially refractory to plasmapheresis and steroids, she was successfully treated with Rituximab and plasmaphersis without any evidence of reactivation of hepatitis.
Criminal Defense in Sensitive Cases: Yao Fuxin, Yang Jianli, Jiang Lijun, Du Daobin, Liu Xiaobo, and Others
Authors: Shaoping Mo , Xia Gao , Xi Lü , Zerui Chen
Published: January 2013

In this chapter, Liu Xiaobo's defense team, led by Mo Shaoping, introduce major subversive cases that they have defended over the years. By setting out the prosecution evidence and arguments, the authors invite readers to pass judgment on the legality of the prosecution, and the constitutionality and legitimacy of the “subversion” crime at its core. The authors also offer a concise account of the substantive and procedural legal difficulties they have encountered throughout their defense, as well as an analysis of the political causes of these difficulties.
Breaking through the Obstacles of Political Isolation and Discrimination
Authors: Weiping Cui
Published: January 2013

This chapter is an account of how Cui Weiping collated the first reactions of intellectuals and artists to Liu Xiabo's conviction and eleven-year sentence. Spurred into action by her own outrage and sense of injustice, Cui moved to collect these comments in the form of “Tweets” — short, concise summaries of what people told her over the phone — and later posted them online on her blog. Together, they make for a fascinating testimony to the mood of the intellectual elites in that consequential moment.
Challenging Authoritarianism through Law
Authors: Hualing Fu
Published: January 2013

This chapter provides a historical background discussion of the legal rights-based weiquan movement in China, traces the tension between the supply and demand of rights, and explains an institutional failure in meeting the increasing demand for rights and the social consequences of that failure. Armed with legal rights, citizens of different social and economic backgrounds have started to assert these and engage in a movement of rightful resistance. Gradually, law has become a rallying point for aggrieved people, and lawyers have become organizers of an emerging social movement. However, the brutal social changes and acute conflicts are often beyond the capacity of legal norms and institutions to grasp. As a result, the legal system has failed to serve as a governing tool for the Party-state and to provide remedies for citizens seeking justice — both are giving up on law and resorting to extralegal and illegal measures to settle the score.
Performance of a new split digital phase lock loop in additive wideband Gaussian noise
Authors: Sarkar Surjadeep , Maulik Ujjwal , Biswas Baidyanath
Published: January 2013

This paper proposes a new split digital phase lock loop (DPLL) in the presence of additive wideband Gaussian noise. The proposed new loop incorporates an additional phase modulation input along with its frequency modulation input in the digitally controlled oscillator of the loop. The present loop eliminates the deleterious effects of wideband Gaussian noise. A better output signal‐to‐noise ratio is achieved using the new split‐loop DPLL. In the design of the loop, the interaction between the loop and the radio frequency filters is avoided by using an in‐phase and quadrature‐phase digitally control oscillator. The proposed split‐loop DPLL is simulated using MATLAB (The MathWorks, Natick, MA, USA)/Simulink environment and System Generator, a tool from Xilinx (Xilinx, Inc., San Jose, CA, USA) used for field programmable gate array design, as well as implemented on a Spartan 3E Starter Kit board. The design is implemented on field programmable gate array using the VHDL [Very High Speed Integrated Circuit (VHSIC) Hardware Description Language] language on Xilinx ISE 13.1. The proposed split‐loop DPLL proves to be better than the conventional split‐loop DPLL from the standpoint of the settling time, the peak time, the rise time, and the peak overshoot as well as from the standpoint of the BER performance for a typical binary phase‐shift keying system and validates against the MATLAB/Simulink results. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of antireflective coatings on poly(methyl methacrylate) substrate by different process parameters
Authors: Chiu Wei‐Ming , Zhang Yuan‐Shun , Tsai Peir‐An , Wu Jyh‐Horng
Published: January 2013

The high/low refractive index organic/inorganic antireflective (AR) hybrid polymers were formed using the sol–gel process, in which TiO2/2‐hydroxyethyl methacrylate (2‐HEMA) (high refractive index hybrid polymer) and SiO2/2‐HEMA (low refractive index hybrid polymer) two‐layer thin films were formed on a hard coating deposited poly(methyl methacrylate) (HC‐PMMA) substrate by both spin coating and dip coating. The relationship between the process parameters and the optical properties, thickness, porosity, surface morphology, and adhesion was determined. The results show that the reflectance of the two‐layer thin films on HC‐PMMA substrate is less than 0.21% (λ = 550 nm), with good adhesion (5B) and a hardness of up to 4H. In addition, the thickness, porosity, and roughness of the films affect refractive index and the antireflection properties of the AR two‐layered thin film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The differences between latent topics in abstracts and citation contexts of citing papers
Authors: Liu Shengbo , Chen Chaomei
Published: January 2013

Although it is commonly expected that the citation context of a reference is likely to provide more detailed and direct information about the nature of a citation, few studies in the literature have specifically addressed the extent to which the information in different parts of a scientific publication differs. Do abstracts tend to use conceptually broader terms than sentences in a citation context in the body of a publication? In this article, we propose a method to analyze and compare latent topics in scientific publications, in particular, from abstracts of papers that cited a target reference and from sentences that cited the target reference. We conducted an experiment and applied topical modeling techniques to full‐text papers in eight biomedicine journals. Topics derived from the two sources are compared in terms of their similarities and broad‐narrow relationships defined based on information entropy. The results show that abstracts and citation contexts are characterized by distinct sets of topics with moderate overlaps. Furthermore, the results confirm that topics from abstracts of citing papers have broader terms than topics from citation contexts formed by citing sentences. The method and the findings could be used to enhance and extend the current methodologies for research evaluation and citation evaluation.
CYP261 enzymes from deep sea bacteria: A clue to conformational heterogeneity in cytochromes P450
Authors: Davydov Dmitri R. , Sineva Elena V. , Davydova Nadezhda Y. , Bartlett Douglas H. , Halpert James R.
Published: January 2013

We have explored the adaptation of the cytochromesP450 (P450) of deep‐sea bacteria to high hydrostatic pressures. Strict conservation of the protein fold and functional importance of protein‐bound water makeP450 a unique subject for the studies of high‐pressure adaptation. Earlier, we expressed and purified a fatty‐acid bindingP450 from the deep‐sea bacteriaPhotobacterium profundumSS9 (CYP261C1). Here, we report purification and initial characterization of its mesophilic ortholog from the shallow‐waterP. profundum3TCK(CYP261C2), as well as another piezophilic enzyme,CYP261D1, from deep‐seaMoritella sp.PE36. Comparison of the three enzymes revealed a striking peculiarity of the piezophilic enzymes. BothCYP261C1 andCYP261D1 possess an apparent pressure‐induced conformational toggle actuated at the pressures commensurate with the physiological pressure of habitation of the host bacteria. Furthermore, in contrast toCYP261C2, the piezophilicCYP261 enzymes may be chromatographically separated into two fractions with different properties, and different thermodynamic parameters of spin equilibrium in particular. According to our concept, the changes in the energy landscape that evolved in pressure‐tolerant enzymes must stabilize the less‐hydrated, closed conformers, which may be transient in the catalytic mechanisms of nonpiezophilic enzymes. The studies of enzymes of piezophiles should help unravel the mechanisms that control water access during the catalytic cycle.
Anti‐inflammatory effects of melatonin in a rat model of caerulein‐induced acute pancreatitis
Authors: Carrasco Cristina , Marchena Ana M. , Holguín‐Arévalo María S. , Martín‐Partido Gervasio , Rodríguez Ana B. , Paredes Sergio D. , Pariente José A.
Published: January 2013

The purpose of our study was to evaluate the protective effect of melatonin in a rat model of caerulein‐induced acute pancreatitis. For the induction of experimental acute pancreatitis, four subcutaneous injections of caerulein (20 µg kg–1 body weight) were given to Wistar rats at 2‐h intervals. Melatonin was injected intraperitoneally (25 mg kg–1 body weight) 30 min before each caerulein injection. After 12 h, rats were sacrificed by decapitation. Blood and pancreas samples were collected and processed for serological and histopathological studies, respectively. Lipase, α‐amylase, corticosterone, total antioxidant power and cytokines interleukin (IL)‐1β, IL‐4 and tumour necrosis factor (TNF)‐α were determined using commercial kits. ANOVA and Tukey tests (P < 0.05) were performed for the statistical analysis of the results. Results showed that the administration of melatonin reduced histological damage induced by caerulein treatment as well as the hyperamylasemia and hyperlipidemia. Corticosterone and antioxidant total power were also reverted to basal activities. Furthermore, melatonin pre‐treatment reduced pro‐inflammatory cytokines IL‐1β and TNF‐α and increased the serum levels of anti‐inflammatory cytokine IL‐4. In conclusion, the findings suggest that the protective effect of melatonin in caerulein‐induced acute pancreatitis is mediated by the anti‐inflammatory ability of this indolamine. Thus, melatonin may have a protective effect against acute pancreatitis. Copyright © 2013 John Wiley & Sons, Ltd.
Progress in the Understanding of the Key Pharmacophoric Features of the Antimalarial Drug Dihydroartemisinin: An Experimental and Theoretical Charge Density Study
Authors: Saleh Gabriele , Soave Raffaella , Lo Presti Leonardo , Destro Riccardo
Published: January 2013

The accurate, experimental charge density distribution,ρ(r), of the potent antimalarial drug dihydroartemisinin (DHA) has been derived for the first time from single‐crystal X‐ray diffraction data atT=100(2) K. Gas‐phase and solid‐state DFT simulations have also been performed to provide a firm basis of comparison with experimental results. The quantum theory of atoms in molecules (QTAIM) has been employed to analyse theρ(r) scalar field, with the aim of classifying and quantifying the key real‐space elements responsible for the known pharmacophoric features of DHA. From the conformational perspective, the bicyclo[3.2.2]nonane system fixes the three‐dimensional arrangement of the 1,2,4‐trioxane bearing the active OO redox centre. This is the most nucleophilic function in DHA and acts as an important CH⋅⋅⋅O acceptor. On the contrary, the rest of the molecular backbone is almost neutral, in accordance with the lipophilic character of the compound. Another remarkable feature is the CO bond length alternation along the O‐C‐O‐C polyether chain, due to correlations between pairs of adjacent CO bonds. These bonding features have been related with possible reactivity routes of the α‐ and β‐DHA epimers, namely 1) the base‐catalysed hemiacetal breakdown and 2) the peroxide reduction. As a general conclusion, the base‐driven proton transfer has significant non‐local effects on the whole polyether chain, whereas DHA reduction is thermodynamically favourable and invariably leads to a significant weakening (or even breaking) of the OO bond. The influence of the hemiacetal stereochemistry on the electronic properties of the system has also been considered. Such findings are discussed in the context of the known chemical reactivity of this class of important antimalarial drugs.
Affinity, Speciation, and Molecular Features of Copper(II) Complexes with a Prion Tetraoctarepeat Domain in Aqueous Solution: Insights into Old and New Results
Authors: Di Natale Giuseppe , Ősz Katalin , Kállay Csilla , Pappalardo Giuseppe , Sanna Daniele , Impellizzeri Giuseppe , Sóvágó Imre , Rizzarelli Enrico
Published: January 2013

Characterization of the copper(II) complexes formed with the tetraoctarepeat peptide at low and high metal‐to‐ligand ratios and in a large pH range, would provide a breakthrough in the interpretation of biological relevance of the different metal complexes of copper(II)‐tetraoctarepeat system. In the present work, the potentiometric, UV/Vis, circular dichroism (CD), and electron paramagnetic resonance (EPR) studies were carried out on copper(II) complexes with a PEG‐ylated derivative of the tetraoctarepeats peptide sequence (Ac‐PEG27‐(PHGGGWGQ)4‐NH2) and the peptide Ac‐(PHGGGWGQ)2‐NH2. Conjugation of tetraoctarepeat peptide sequence with polyethyleneglycol improved the solubility of the copper(II) complexes. The results enable a straightforward explanation of the conflicting results originated from the underestimation of all metal–ligand equilibria and the ensuing speciation. A complete and reliable speciation is therefore obtained with the released affinity and binding details of the main complexes species formed in aqueous solution. The results contribute to clarify the discrepancies of several studies in which the authors ascribe the redox activity of copper(II)‐tetraoctarepeat system considering only the average effects of several coexisting species with very different stoichiometries and binding modes.
A group‐choose algorithm supporting virtual organization creation for workflow deployment in cloud environment
Authors: Pan Maolin , Li MiaoMiao , Yu Yang
Published: January 2013

Virtual organization (VO) is a main organizational paradigm for enterprises to collaborate in the rapidly changing environment. However, finding partners for VO creation has great challenges on Internet, because a VO initiator is blinded without enough partners' information. The problem of VO creation in cloud environment is discussed. A VO creating algorithm (called Group‐Choose) based on reputation system is presented to help initiator minimize the operating risk on Internet. In the algorithm, a VO initiator aggregates partners' trust evaluations of candidates to select new partners for VO, instead of evaluating candidate's trust only by itself. The third‐party assessment and Time Slide Window are used in peer‐to‐peer trust evaluation to make the model more adaptive in the dynamic environment. The proposed method focuses on the reputation data, without taking other factors into consideration. Compared with PathTrust and PeerTrust, the Group‐Choose algorithm for VO creation has better performance in resisting conspiracy attack and periodic attack. Copyright © 2013 John Wiley & Sons, Ltd.
A concurrent van Emde Boas array as a fast and simple concurrent dynamic set alternative
Authors: Kułakowski Konrad
Published: January 2013

Increasing demand for computationally efficient algorithms and processors has turned the attention of researchers toward parallel and concurrent solutions. Because the frequency of contemporary processors cannot be tweaked infinitely, the only hopes for squeezing more performance from computers are parallel processing and parallel computation. The important part of every parallel solution is concurrent data structures, which allow multithread programming environments to be taken advantage of. In this article, a new concurrent dynamic set structure is proposed. It is based on the van Emde Boas trees concept, where on every node of a tree, an array of the node's children is stored. The structure is equipped with a simple but effective locking algorithm, which allows it to be used concurrently by any number of threads. The presented algorithm idea is accompanied by an experimental implementation written in JAVA 6. Preliminary tests prove that, especially for moderately larger data sets with a predominance of read operations, the concurrent van Emde Boas array proposed in this article may be a viable alternative for other structures providing a similar functionality. Copyright © 2013 John Wiley & Sons, Ltd.
Polar paradox revisited: analogous pairs of hydrophilic and lipophilic antioxidants in linoleic acid emulsion containing Cu(II)
Authors: Bakır Temelkan , Sönmezoğlu İnci , İmer Filiz , Apak Reşat
Published: January 2013

Background

Literature data are scarce on the activities of analogous pairs of hydrophilic and lipophilic antioxidants related to the ‘polar paradox’ distinguishing antioxidants based on their partitioning between lipids and water. The peroxidation of linoleic acid (LA) in the presence of either Cu(II) ions alone or Cu(II) ions combined with Trolox (TR), ascorbic acid (AA), hydroquinone (HQ) and gallic acid (GA), as hydrophilic antioxidants, or with α‐tocopherol (TocH), ascorbyl palmitate (AP), tert‐butyl hydroquinone (TBHQ) and propyl gallate (PG), as their respective lipophilic analogues, was investigated in aerated and incubated emulsions at 37 °C and pH 7.

Results

LA peroxidation induced by Cu(II) followed pseudo‐first‐order kinetics with respect to the formation of primary (hydroperoxides) and secondary (aldehyde‐ and ketone‐like) oxidation products, which were determined by ferric thiocyanate (Fe(III)‐SCN) and thiobarbituric acid‐reactive substances (TBARS) methods respectively. With the exception of TocH at certain concentrations, the tested compounds showed antioxidant behaviour depending on their polarities. The results were evaluated in the light of structure–activity relationships and the polar paradox.

Conclusion

The results of this study partly confirm the hypothesis that the polar paradox experiences limitations in oil‐in‐water emulsions and that its validity is also dependent on the concentrations of the antioxidants employed. © 2013 Society of Chemical Industry
Determination of bisphenol A in thermal printing papers treated by alkaline aqueous solution using the combination of single‐drop microextraction and HPLC
Authors: Gao Leihong , Zou Jing , Liu Haihong , Zeng Jingbin , Wang Yiru , Chen Xi
Published: January 2013

A method for the quantitative determination of bisphenol A in thermal printing paper was developed and validated. Bisphenol A was extracted from the paper samples using 2% NaOH solution, then the extracted analyte was enriched using single‐drop microextraction followed by HPLC analysis. Several parameters relating to the single‐drop microextraction efficiency including extraction solvent, extraction temperature and time, stirring rate, and pH of donor phase were studied and optimized. Spiked recovery of bisphenol A at 20 and 5 mg/g was found to be 95.8 and 108%, and the method detection limit and method quantification limit was 0.03 and 0.01 mg/g, respectively. Under the optimized conditions, the proposed method was applied to the determination of bisphenol A in seven types of thermal printing paper samples, and the concentration of bisphenol A was found in the range of 0.53–20.9 mg/g. The considerably minimum usage of organic solvents (5 μL 1‐octanol) and high enrichment factor (189–197) in the sample preparation are the two highlighted advantages in comparison with previously published works.
Challenge of joining and surface technologies for light weight constructions in automobile applications
Authors: Reinhold B. , Blücher D. , Korte M.
Published: January 2013

Zur Senkung des Fahrzeuggewichtes sollen zukünftig warmgewalzte Magnesium‐Blech‐Legierungen wie auch CFK‐Bauteile in die Karosseriestruktur integriert werden. Beide Leichtbaumaterialien sind mit verzinkten Stählen sowie mit Aluminium ohne aufwendige Korrosionsschutzmaßnahmen nicht kombinierbar. Aus elektrochemischen Untersuchungen wird bezüglich der Vorbehandlung von Magnesium eine oxidkeramische Oberflächenausbildung durch plasmachemische Oxydation als aussichtsreich eingeschätzt. Nach dem mechanischen Fügen mit Aluminium können derartige porenbehaftete Substrate mittels KTL in hoher Qualität lackiert werden, bevor der weitere Lackaufbau erfolgt. CFK‐Bauteile indessen haben – im Gegensatz zu Magnesium – elektrochemisch ein sehr edles Verhalten und verursachen starke Kontaktkorrosion an metallischen Anbauteilen, wenn die C‐Fasern durch den Bauteil‐Beschnitt frei liegen. Für das mechanische Fügen von CFK mittels Schraub‐ und Niettechnik eignen sich daher nur Verbindungselemente aus austenitischen Stählen oder aus Titan‐Legierungen (z.B. TiAl6V4). Aus Sicht der Materialverträglichkeit von CFK mit anderen Blech‐Materialien, vorzugsweise mit Aluminium, ist die Verklebung mit zusätzlicher Abdichtung entsprechender Flansche zwingend erforderlich.
New practical tools for the implementation and use of ultrafast 2D NMR experiments
Authors: Pathan Meerakhan , Charrier Benoît , Tea Illa , Akoka Serge , Giraudeau Patrick
Published: January 2013

Ultrafast (UF) 2D NMR is a very promising methodology enabling the acquisition of 2D spectra in a single scan. In the last few years, the analytical performance of UF 2D NMR has been highly increased, consequently maximizing its range of applications. However, its implementation and use by non‐specialists are far from being straightforward, because of the specific acquisition and processing procedures and parameters characterizing UF NMR. To make this methodology implementable and applicable by non‐specialists, we developed a simple routine capable of translating conventional parameters (spectral widths and transmitter frequencies) into specific UF parameters (gradient and chirp pulse parameters). This macro was subsequently implemented in a Web page, which is available for external users. Although the algorithm was designed for two widely used 2D experiments, COSY and HSQC, it can easily be extended to any other pulse sequence. The robustness of this routine was verified successfully on a variety of small molecules. We believe that this tool will eliminate much of the technical difficulties related to UF 2D NMR and will make the technique accessible to a wider audience of organic and analytical chemists. Copyright © 2013 John Wiley & Sons, Ltd.
Professional Confidence: Conceptions Held by Novice Occupational Therapists in South Africa
Authors: Holland Kathlyn Elena , Middleton Lyn , Uys Leana
Published: January 2013

This study aimed to explore how novice occupational therapists conceptualized professional confidence. Professional confidence is a dynamic personal belief that matures over time. It is closely linked to both competence and professional identity ensuring fitness for practice. Although professional confidence has been defined and a number of its attributes have been identified, how practitioners understand or conceptualize the phenomenon is not clearly understood. Eight novice occupational therapists undertaking their community service year in South Africa during 2011 participated in the study. Data, collected during semi‐structured interviews, were analyzed using phenomenographic methodology. From the participant's descriptions, three qualitatively different ways of understanding professional confidence emerged from the data, namely knowing as an occupational therapist, believing you are an occupational therapist and being an occupational therapist. The outcome space was also described. The study did not purport to gauge whether the novice therapists were in fact confident. As professional confidence is a maturing self‐belief, the findings are limited to novice occupational therapists. The findings contribute to a growing understanding of professional confidence in occupational therapy. Further research is needed in terms of what informs the conceptions held by novice therapists and how professional confidence can be assessed in graduates on completion of their educational programme. Copyright © 2013 John Wiley & Sons, Ltd.
Vigilant Self–regulation and Costly Punishment in Public Goods Situations
Authors: Pfattheicher Stefan , Keller Johannes
Published: January 2013

Applying regulatory focus theory to the context of social dilemma situations, the present research demonstrates that individual differences in vigilant, prevention–focused self–regulation predict the tendency to invest private resources to punish uncooperative interaction partners (costly punishment), a behaviour that typically has strong positive effects on the collective level of cooperation. Analyses further support the distinctiveness of the vigilance system proposed in regulatory focus theory (prevention focus) in comparison with general defensive inhibitory tendencies (measured with Carver and White's Behavioral Inhibition System scale). Results document that individual differences in prevention–focused self–regulation but not differences in general defensive inhibitory tendencies are positively related to costly punishment. In sum, the findings indicate that vigilant, prevention–focused self–regulation plays a crucial role in the context of sanctions that enforce cooperation. Copyright © 2013 John Wiley & Sons, Ltd.
Deterministic algorithms for matrix completion
Authors: Heiman Eyal , Schechtman Gideon , Shraibman Adi
Published: January 2013

The goal of the matrix completion problem is to retrieve an unknown real matrix from a small subset of its entries. This problem comes up in many application areas, and has received a great deal of attention in the context of the Netflix challenge. This setup usually represents our partial knowledge of some information domain. Unknown entries may be due to the unavailability of some relevant experimental data.

One approach to this problem starts by selecting a complexity measure of matrices, such as rank or trace norm. The corresponding algorithm outputs a matrix of lowest possible complexity that agrees with the partially specified matrix. The performance of the above algorithm under the assumption that the revealed entries are sampled randomly has received considerable attention (e.g., Refs. Srebro et al., 2005; COLT, 2005; Foygel and Srebro, 2011; Candes and Tao, 2010; Recht, 2009; Keshavan et al., 2010; Koltchinskii et al., 2010). Here we ask what can be said if the observed entries are chosen deterministically. We prove generalization error bounds for such deterministic algorithms, that resemble the results of Refs. Srebro et al. (2005); COLT (2005); Foygel and Srebro (2011) for the randomized algorithms.

We still do not understand which sets of entries in a given matrix can be used to properly reconstruct it. Our hope is that the present work sheds some light on this problem. © 2013 Wiley Periodicals, Inc. Random Struct. Alg., 45, 306–317, 2014
When does combining markers improve classification performance and what are implications for practice?
Authors: Bansal Aasthaa , Sullivan Pepe Margaret
Published: January 2013

When an existing standard marker does not have sufficient classification accuracy on its own, new markers are sought with the goal of yielding a combination with better performance. The primary criterion for selecting new markers is that they have good performance on their own and preferably be uncorrelated with the standard. Most often linear combinations are considered. In this paper, we investigate the increment in performance that is possible by combining a novel continuous marker with a moderately performing standard continuous marker under a variety of biologically motivated models for their joint distribution. We find that an uncorrelated continuous marker with moderate performance on its own usually yields only minimally improved performance. We identify other settings that lead to large improvements, including a novel marker that has very poor performance on its own but is highly correlated with the standard and a novel marker with poor to moderate performance that is highly correlated with the standard but only in one class category. These results suggest changing current strategies for identifying markers to be included in panels for possible combination. Using simulated and real datasets, we examine the merits of a broadened strategy that selects panels of markers as candidates on the basis of their joint performance with existing markers, compared with the standard strategy that selects markers on the basis of their marginal performance. We find that a broadened strategy can be fruitful but necessitates using studies with large numbers of subjects. Copyright © 2013 John Wiley & Sons, Ltd.
Vertical integration, innovation, and alliance portfolio size: Implications for firm performance
Authors: Lahiri Nandini , Narayanan Sriram
Published: January 2013

We examine the consequences of alliance portfolio configuration by focusing on contingencies that affect the impact of alliance portfolio size on innovation and financial performance. While increasing alliance portfolio size is expected to positively impact innovation and financial performance, we propose that, at high levels of innovation of the focal firm, increasing alliance portfolio size dampens financial performance. We also propose that firm boundaries moderate the impact of alliance portfolio size on innovation and financial performance differently. Specifically, vertically integrated firms benefit less (more) than their vertically specialized counterparts in leveraging higher innovation (financial) performance with increasing alliance portfolio size. Our analysis suggests that both vertical scope and innovation levels of the firm play an important role in understanding how alliance portfolios impact performance. Copyright © 2013 John Wiley & Sons, Ltd.
A theoretical and empirical investigation of property rights sharing in outsourced research, development, and engineering relationships
Authors: Carson Stephen J. , John George
Published: January 2013

This article considers the use of property rights to structure ex post bargaining positions in client‐sponsoredRD&E. By focusing on the positive externality created by uses of the technology not targeted by the client, the theory produces a novel set of predictions that diverge from standard transaction cost and property rights reasoning; that is, greater contractor property rights are associated with more transaction‐specific investments by the client. Contractor property rights are also predicted to increase as environmental uncertainty increases and as more applications of the technology fall outside the client's intended fields of use. Contract‐level data from 147RD&Eagreements in technology‐intensive settings provide support for these predictions. A secondary examination shows that clients who share property rights with their contractors face reduced opportunism during project execution. Copyright © 2013 John Wiley & Sons, Ltd.