bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Application of High‐speed Counter‐current Chromatography for Separation and Purification of Bungeiside‐A, Bungeiside‐B and Baishouwubenzophenone from Cynanchum bungei Decne
Authors: Sun Yinshi , Lin Hongmei , Wang Jianhua , Hu Jiangning , Liu Zhengbo , Gao Aidong 
Published: April 2011

ABSTRACTIntroductionCynanchum bungei Decne (Baishouwu in China), is a famous traditional Chinese medicine that has been widely used as a tonic medicine or health food for centuries. Bungeiside‐A, bungeiside‐B and baishouwubenzophenone, as the major bioactive constituents in C. bungei, are challenging to separate and purify since bungeiside‐A and ‐B are present in very low concentrations and have similar structures and high polarity.ObjectiveTo develop a method of isolation and purification of bungeiside‐A and ‐B and baishouwubenzophenone from the Chinese medicinal plant Cynanchum bungei Decne by high‐speed counter‐current chromatography (HSCCC).MethodologyThe roots of C. bungei were extracted with light‐petroleum (60–90 °C) and chloroform to remove the lipid substance. Then the residuals were extracted with methanol. The methanol extract was prepared for the subsequent HSCCC separation. The simple HSCCC method of separation and purification of bungeiside‐A and ‐B and baishouwubenzophenone was established according to the solvent system, which was selected according to the measurement of partition coefficient (K). The purities of target compounds were test by HPLC and the structure was identified by 1H NMR and 13C NMR.ResultsBungeiside‐A (9.4 mg), bungeiside‐B (8.6 mg) and baishouwubenzophenone (5.7 mg) were obtained from 1.5 g of the methanol extract with purities of 93.2, 98.7 and 95.4%, respectively.ConclusionThese results clearly demonstrate that HSCCC is a powerful tool for isolating and purifying components with similar structures, low concentration and high polarity from medicinal plant, such as bungeiside‐A and ‐B and baishouwubenzophenone. Copyright © 2011 John Wiley & Sons, Ltd.
Photovoltaics literature survey (no. 85)
Authors: Shrestha Santosh 
Published: April 2011

AbstractIn order to help keep readers up‐to‐date in the field each issue of Progress in Photovoltaics will contain a list of recently published journal articles most relevant to its aims and scope. This list is drawn from an extremely wide range of journals, including IEEE Transactions on Electron Devices, Journal of Applied Physics, Applied Physics Letters, Progress in Photovoltaics and Solar Energy Materials and Solar Cells. To assist the reader, the list is separated into broad categories, but please note that these classifications are by no means strict. Also note that inclusion in the list is not an endorsement of a paper's quality. If you have any suggestions please email Santosh Shrestha at s.shrestha@unsw.edu.au.
Prevalence and correlates of depressive disorders in outpatients with breast cancer in Lagos, Nigeria
Authors: Popoola Abiodun O. , Adewuya Abiodun O. 
Published: April 2011

AbstractObjectiveWhile the physical complications of breast cancer are often recognized and well managed, the psychological sequelae, especially depression are often unrecognized by healthcare providers and therefore under treated. This study aimed to assess the rate and correlate of depressive disorders in breast cancer survivors in Lagos, Nigeria.MethodsPatients (n = 124) recruited from a breast cancer outpatient clinic were assessed for the DSM‐IV diagnosis of depressive disorders using the Mini International Neuropsychiatric Interview (MINI). The staging of the cancer, length of diagnosis and treatment type were recorded. Also socio‐demographic details and their perceived level of social support were obtained.ResultsTwenty‐one (16.9%) were diagnosed as having Major Depressive Disorder, while 29 (23.4%) had Minor depressive disorder making a total of 50 (40.3%) cases with depression. The independent correlates of depression included being not married (odds ratio (OR) 3.09, 95% CI 1.30–7.42), perceived poor social support (OR 5.38, 95% CI 1.88–16.63) and advanced stage of the cancer (OR 3.22, 95% CI 1.32–8.26).ConclusionOur study suggests a high rate of associated depression among patients with breast cancer in our environment. Clinicians should be encouraged and empowered to probe for symptoms of depression in these patient while larger hypothesis‐driven studies are needed.Copyright © 2011 John Wiley & Sons, Ltd.
Plastic bronchitis: Resolution after heart transplantation
Authors: ElMallah Mai K. , Prabhakaran Sreekala , Chesrown Sarah E. 
Published: April 2011

AbstractPlastic bronchitis (PB) is a rare cause of obstructive airway disease in patients who have undergone partially corrective surgery for congenital heart disease (CHD). The etiology of plastic bronchitis in such patients is ill‐defined, and treatment is ineffective. We report resolution of PB and severe obstructive airway disease after heart transplantation in a patient with CHD. Pediatr. Pulmonol. 2011; 46:824–825. © 2011 Wiley‐Liss, Inc.
Sinus vein thrombosis as presenting finding in the congenital central hypoventilation syndrome: An insight on the pathophysiology of the association
Authors: Joseph Leon , Goldberg Shmuel , Shahroor Sarit , Gomori Moshe , Mimouni Francis B. , Picard Elie 
Published: April 2011

AbstractCongenital central hypoventilation syndrome (CCHS) is an increasingly recognized diagnosis causing central hypoventilation and may be definitively diagnosed by genetic testing. Previous authors reported the association between CCHS and central sinus venous thrombosis (CSVT) and hypothesized that CCHS could be secondary to CSVT. We report a case of CCHS with the typical PHOX2B mutation who also suffered from CSVT. We assume that effects, secondary to CCHS, upon the central venous system may explain the etiological connection between CSVT and CCHS including dysautoregulation, venous stasis or polycythemia. We believe that CCHS should be included in the differential diagnosis of patients with CSVT accompanied by respiratory abnormalities. Pediatr. Pulmonol. 2011; 46:826–828. © 2011 Wiley‐Liss, Inc.
Mannitol dry powder challenge in comparison with exercise testing in children
Authors: Barben Juerg , Kuehni Claudia E. , Strippoli Marie‐Pierre F. , Schiller Barbara , Hammer Juerg , Trachsel Daniel ,   On behalf of the Swiss Paediatric Respiratory Research Group
Published: April 2011

AbstractRationaleMannitol dry powder (MDP) challenge is an indirect bronchial provocation test, which is well studied in adults but not established for children.ObjectiveWe compared feasibility, validity, and clinical significance of MDP challenge with exercise testing in children in a clinical setting.MethodsChildren aged 6–16 years, referred to two respiratory outpatient clinics for possible asthma diagnosis, underwent standardized exercise testing followed within a week by an MDP challenge (Aridol™, Pharmaxis, Australia). Agreement between the two challenge tests using Cohen's kappa and receiving operating characteristic (ROC) curves was compared.ResultsOne hundred eleven children performed both challenge tests. Twelve children were excluded due to exhaustion or insufficient cooperation (11 at the exercise test, 1 at the MDP challenge), leaving 99 children (mean ± SD age 11.5 ± 2.7 years) for analysis. MDP tests were well accepted, with minor side effects and a shorter duration than exercise tests. The MDP challenge was positive in 29 children (29%), the exercise test in 21 (21%). Both tests were concordant in 83 children (84%), with moderate agreement (κ = 0.58, 95% CI 0.39–0.76). Positive and negative predictive values of the MDP challenge for exercise‐induced bronchoconstriction were 68% and 89%. The overall ability of MDP challenge to separate children with or without positive exercise tests was good (area under the ROC curve 0.83).ConclusionsMDP challenge test is feasible in children and is a suitable alternative for bronchial challenge testing in childhood. Pediatr. Pulmonol. 2011; 46:842–848. © 2011 Wiley‐Liss, Inc.
Assessment of flexible backbone protein design methods for sequence library prediction in the therapeutic antibody Herceptin–HER2 interface
Authors: Babor Mariana , Mandell Daniel J. , Kortemme Tanja 
Published: April 2011

AbstractComputational protein design methods can complement experimental screening and selection techniques by predicting libraries of low‐energy sequences compatible with a desired structure and function. Incorporating backbone flexibility in computational design allows conformational adjustments that should broaden the range of predicted low‐energy sequences. Here, we evaluate computational predictions of sequence libraries from different protocols for modeling backbone flexibility using the complex between the therapeutic antibody Herceptin and its target human epidermal growth factor receptor 2 (HER2) as a model system. Within the program RosettaDesign, three methods are compared: The first two use ensembles of structures generated by Monte Carlo protocols for near‐native conformational sampling: kinematic closure (KIC) and backrub, and the third method uses snapshots from molecular dynamics (MD) simulations. KIC or backrub methods were better able to identify the amino acid residues experimentally observed by phage display in the Herceptin–HER2 interface than MD snapshots, which generated much larger conformational and sequence diversity. KIC and backrub, as well as fixed backbone simulations, captured the key mutation Asp98Trp in Herceptin, which leads to a further threefold affinity improvement of the already subnanomolar parental Herceptin‐HER2 interface. Modeling subtle backbone conformational changes may assist in the design of sequence libraries for improving the affinity of antibody–antigen interfaces and could be suitable for other protein complexes for which structural information is available.
Structural and functional characterization of Schistosoma mansoni Thioredoxin
Authors: Boumis Giovanna , Angelucci Francesco , Bellelli Andrea , Brunori Maurizio , Dimastrogiovanni Daniela , Miele Adriana E. 
Published: April 2011

AbstractSchistosomiasis, the human parasitosis caused by various species of the blood‐fluke Schistosoma, is a debilitating disease affecting 200 million people in tropical areas. The massive administration of the only effective drug, praziquantel, leads to the appearance of less sensitive parasite strains, thus, making urgent the search for new therapeutic approaches and new suitable targets. The thiol‐mediated detoxification pathway has been identified as a promising target, being essential during all the parasite developmental stages and sufficiently different from the host counterpart. As a part of a project aimed at the structural characterization of all the proteins involved in this pathway, we describe hereby the high‐resolution crystal structure of Schistosoma mansoni Thioredoxin (SmTrx) in three states, namely: the wild‐type oxidized adult enzyme and the oxidized and reduced forms of a juvenile isoform, carrying an N‐terminal extension. SmTrx shows a typical thioredoxin fold, highly similar to the other components of the superfamily. Although probably unlikely to be a reasonable drug target given its high similarity with the human counterpart, SmTrx completes the characterization of the whole set of thiol‐mediated detoxification pathway components. Moreover, it can reduce oxidized glutathione and is one of the few defence proteins expressed in mature eggs and in the hatch fluid, thus confirming an important role in the parasite. We believe its crystal structure may provide clues for the formation of granulomas and the pathogenesis of the chronic disease.
Polymer‐based cell‐free expression of ligand‐binding family B G‐protein coupled receptors without detergents
Authors: Klammt Christian , Perrin Marilyn H. , Maslennikov Innokentiy , Renault Ludovic , Krupa Martin , Kwiatkowski Witek , Stahlberg Henning , Vale Wylie , Choe Senyon 
Published: April 2011

AbstractG‐protein coupled receptors (GPCRs) constitute the largest family of intercellular signaling molecules and are estimated to be the target of more than 50% of all modern drugs. As with most integral membrane proteins (IMPs), a major bottleneck in the structural and biochemical analysis of GPCRs is their expression by conventional expression systems. Cell‐free (CF) expression provides a relatively new and powerful tool for obtaining preparative amounts of IMPs. However, in the case of GPCRs, insufficient homogeneity of the targeted protein is a problem as the in vitro expression is mainly done with detergents, in which aggregation and solubilization difficulties, as well as problems with proper folding of hydrophilic domains, are common. Here, we report that using CF expression with the help of a fructose‐based polymer, NV10 polymer (NVoy), we obtained preparative amounts of homogeneous GPCRs from the three GPCR families. We demonstrate that two GPCR B family members, corticotrophin‐releasing factor receptors 1 and 2β are not only solubilized in NVoy but also have functional ligand‐binding characteristics with different agonists and antagonists in a detergent‐free environment as well. Our findings open new possibilities for functional and structural studies of GPCRs and IMPs in general.
Non‐intrusive Measurements of Headspace Gas Composition in Liquid Food Packages Made of Translucent Materials
Authors: Lewander M. , Lundin P. , Svensson T. , Svanberg S. , Olsson A. 
Published: April 2011

SUMMARYThe increase in chilled food consumption requires enhanced food safety and quality assurance. Food deteriorating processes are affected by the presence of oxygen, combined with factors such as time and temperature. To slow down deterioration processes and prolong shelf life, traditional packaging methods are being replaced by modified atmosphere packaging, for example. Oxygen, which is naturally present in the headspace of most food packages, is then reduced and controlled. Many sensing techniques for food quality assurance have been developed; however, almost all are intrusive, increasing the complication level and causing sample waste. The purpose of this paper is to introduce a non‐intrusive technique [gas in scattering media absorption spectroscopy (GASMAS)] for measuring gas composition in the headspace of liquid food packages. The GASMAS method uses diode laser absorption spectroscopy combined with diffuse light propagation to analyse gas located inside solids and liquids. By illuminating the package from the outside and analysing the scattered light that emerges, the absorption from the gas inside the headspace can be studied.The GASMAS technique was evaluated on a series of carton packages with a high‐quality orange juice and a nitrogen headspace. A clear variation in oxygen content was measured for samples with different storage times. The results demonstrate the possibility of using the GASMAS method for non‐intrusive quality measurements in food products and packaging. They also indicate the potential for the non‐intrusive quality assurance applications without waste of samples. A further development of the technique could include ‘in‐line’ quality control of packed food items throughout the food packaging supply chain. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of cage size on the third‐order optical properties of endohedral metallofullerenes Sc3N@C2n (2n = 68, 70, 78, and 80): A theoretical study
Authors: Wang Jin‐Yun , Lin Chen‐Sheng , Zhang Min‐Yi , Chai Guo‐Liang , Cheng Wen‐Dan 
Published: April 2011

AbstractGeometrical structures of the investigated endohedral metallofullerenes Sc3N@C2n (2n = 68, 70, 78, and 80) were optimized at the B3LYP/6‐31G* level. The analyses of electronic structures display that the contribution of fullerene cage to the lowest unoccupied molecular orbital decreases as the cage size increases. Based on the optimized structures, the time‐dependent density functional theory combined with the sum‐over‐states method was used to investigate their nonlinear optical properties. Calculated third‐order polarizabilities γ and two‐photon absorption (TPA) cross‐section δ do not present the monotone variation with the size of fullerene cage, with largest γ of 0.48 × 10−34 esu for Sc3N@C78 in static state, and largest δ of 12.374 GM for Sc3N@C70 in the wavelength of 902.5 nm. However, the obtained TPA resonant peaks shift red with the size of fullerene cage. By analyzing the electronic origin of the third‐order optical properties, it is found that the charge transfers from the fullerene cage to the encapsulated Sc3N cluster make important contributions to the studied properties. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Structural properties and nonlinear optical responses of superatom compounds BF4‐M (M = Li, FLi2, OLi3, NLi4)
Authors: Yang Hui , Li Ying , Wu Di , Li Zhi‐ru 
Published: April 2011

AbstractA new type of superhalogen‐(super)alkali compound, BF4‐M (M = Li, FLi2, OLi3, NLi4), is theoretically characterized at the MP2/6‐311+G(3df) level. The interaction between superhalogen BF4 and different shaped (super)alkali M is found to be strong and ionic in nature. Bond energies of these BF4‐M species are in the range of 200.0–226.7 kcal/mol at the CCSD(T)/6‐311+G(3df) level, which are much larger than the traditional ionic bond energy of 130.1 kcal/mol of FLi. In addition, different from the alkali halides, the BF4‐M compounds prefer to dissociate into ions rather than neutral fragments. The energetic properties of BF4‐M are found to be closely related to the size of the M subunit. The different effects of superalkali and superhalogen subunits on the nonlinear optical (NLO) properties of such superatom compounds are also revealed. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Second‐order nonlinear optical responses switching of N∧N∧N ruthenium carboxylate complexes with proton‐electron transfer
Authors: Liu Yan , Yang Guo‐Chun , Liu Chun‐Guang , Sun Shi‐Ling , Qiu Yong‐Qing 
Published: April 2011

AbstractIn this article, the nonlinear optical (NLO) switching action of Ru(III/II) carboxylate complexes was investigated by density functional theory (DFT). Among the studied complexed, Ru(III)PhCOO− has the largest β value of 4972 × 10−30 esu. Through the proton transfer (PT) process, the COOH group of Ru(III)PhCOOH and Ru(III)COOH complexes can form the COO− group. Then, COO− group acts as a strong donor and Ru(III) acts as an acceptor, which may be the most favorably used in the development of metal complexes NLO material. The redox NLO switching and PT NLO switching of Ru(III)PhCOO−, Ru(III)PhCOOH, Ru(II)PhCOO−, and Ru(II)PhCOOH complexes have been studied. The β value of Ru(III)PhCOO− complex is ∼36 and ∼48 times larger than those of reduced Ru(II)PhCOO− and Ru(II)PhCOOH, respectively. Note that the β value of deprotonated Ru(III)PhCOO− is ∼215 times larger than that of Ru(III)PhCOOH. The molecular electrostatic potential analysis also confirms that Ru(III)PhCOOH may have poor performance in the second‐order NLO response. In addition, the TDDFT calculations show that the ligand to metal charge transfer transition lead to the largest β value of the Ru(III)PhCOO− complex. This investigation provides important insight into the remarkably large NLO properties and NLO switching of Ru(III/II) carboxylate complexes. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 000: 000–000, 2011
Dynamic monte carlo simulations of NO decomposition on Pt(100): Temperature‐programmed desorption spectra
Authors: Álvarez‐Falcón Leny , Vicente Luis 
Published: April 2011

AbstractThe decomposition of absorbed NO on a Pt(100) surface is studied by using a dynamic Monte Carlo method on a square lattice at low pressure conditions. The N2 temperature‐programmed desorption spectra were simulated considering the presence or absence of lateral interactions. Moreover, the effect on NO dissociation rate, the limiting step in the whole reaction, is inhibited by coadsorbed NO, N, and O molecules. The dissociation rate for NO and N2 desorption are enhanced by the presence of adsorbed atoms as nearest neighbors. In these simulations, values of experimental parameters, such as adsorption, desorption, and diffusion of the reactants, are included. The phenomenon is studied varying the temperature in the range of 300–550 K. Our simulations are positively compared with experimental spectra and calculated mean field models. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem 112:1803–1809, 2012
Theoretical investigation of half‐metallicity in Co/Ni substituted AlN
Authors: Arif Suneela , Ahmad Iftikhar , Amin Bin 
Published: April 2011

AbstractResults of Co and Ni substituted AlN in the zinc blende phase are presented. For spin up states, the hybridized N‐2p and Co/Ni‐3d states form the valance bands with a bandgap around the Fermi level for both materials, while in the case of the spin down states, the hybridized states cross the Fermi level and hence show metallic nature. It is found that, Al0.75Co0.25N and Al0.75Ni0.25N are ferromagnetic materials with magnetic moments of 4 μB and 3 μB, respectively. The integer magnetic moments and the full spin polarization at the Fermi level make these compounds half‐metallic semiconductors. Furthermore it is also found that the interaction with the N‐2p state splits the 5‐fold degenerate Co/Ni‐3d states into t2g and eg states. The t2g states are located at higher energies than the eg states caused by the tetrahedral symmetry of these compounds. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
A stepwise mechanism for the uncatalyzed michael addition of acetylacetone to methyl vinyl ketone
Authors: Deuri Sanjib , Phukan Prodeep 
Published: April 2011

AbstractA stepwise mechanism for the uncatalyzed Michael addition of acetylacetone (AcAc) to methyl vinyl ketone (MVK) has been studied by ab initio calculations at the MP2/6‐31+G (d, p)// B3LYP/6‐31+G (d, p) level of theory. This stepwise mechanism is initiated by a Diels–Alder‐type attack of MVK on the double bond of thecis‐enol of AcAc followed by cleavage of the cycloadduct and proton transfer leading to the formal Michael adduct. Nature of interaction between AcAc and MVK has been probed using reactivity descriptors defined within the context of conceptual DFT. This stepwise mechanism is found to have a low barrier than the concerted mechanism proposed earlier. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Calculation of the H2+ rovibrational energies and spectroscopic constants in the 2pπ, 3dσ, 4dσ, 4fπ, 4fσ, 5gσ, and 6iσ electronic states
Authors: Vila Henrique Vieira Rivera , Leal Luciano Almeida , Fonseca A. L. A. , Gargano Ricardo 
Published: April 2011

AbstractStarting with the Hamilton‐Jacobi equation, Campos et al. have applied Hylleraas' method along with the series obtained by Wind‐Jaffe to several molecular ions, among which the H2+ system, to determine their electronic energies in different states. In this work, we have fitted the potential energy curves for the 2pπ, 3dσ, 4dσ, 4fπ, 4fσ, 5gσ, and 6iσ electronic states of the H2+ ion employing the Rydberg generalized function. From these fittings, the spectroscopic constants and the rovibrational energies have been determined by two distinct methods: Dunham's and the discrete variable representation. The theoretically obtained results are in a satisfactory agreement and are expected to provide a comparison source to future works in the experimental field. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011