bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Reactivity of Mononuclear Iron Models of [Fe]‐Hydrogenase that Contain an Acylmethylpyridinol Ligand
Authors: Hu Bowen , Chen Dafa , Hu Xile 
Published: January 2014

Abstract[Fe]‐hydrogenase has a single iron‐containing active site that features an acylmethylpyridinol ligand. This unique ligand environment had yet to be reproduced in synthetic models; however the synthesis and reactivity of a new class of small molecule mimics of [Fe]‐hydrogenase in which a mono‐iron center is ligated by an acylmethylpyridinol ligand has now been achieved. Key to the preparation of these model compounds is the successful CO cleavage of an alkyl ether moiety to form the desired pyridinol ligand. Reaction of solvated complex [(2‐CH2CO‐6‐HOC5H3N)Fe(CO)2(CH3CN)2]+(BF4)− with thiols or thiophenols in the presence of NEt3 yielded 5‐coordinate iron thiolate complexes. Further derivation produced complexes [(2‐CH2CO‐6‐HOC5H3N)Fe(CO)2(SCH2CH2OH)] and [(2‐CH2CO‐6‐HOC5H3N)Fe(CO)2(CH3COO)], which can be regarded as models of FeGP cofactors of [Fe]‐hydrogenase extracted by 2‐mercaptoethanol and acetic acid, respectively. When the derivative complexes were treated with HBF4⋅Et2O, the solvated complex was regenerated by protonation of the thiolate ligands. The reactivity of several models with CO, isocyanide, cyanide, and H2 was also investigated.
Mitochondrial Fragmentation Is an Important Cellular Event Induced by Ruthenium(II) Polypyridyl Complexes in Osteosarcoma Cells
Authors: Du Yanxin , Fu Xiaoyan , Li Hong , Chen Bolai , Guo Yuhai , Su Guoyi , Zhang Hu , Ning Feipeng , Lin Yongpeng , Mei Wenjie , Chen Tianfeng 
Published: January 2014

AbstractA series of ruthenium(II) polypyridyl complexes were synthesized and evaluated for their in vitro anticancer activities. The results showed that ruthenium polypyridyl complexes, especially [Ru(bpy)2(p‐tFPIP)]2+ (2 a; bpy=bipyridine, tFPIP=2‐(2‐trifluoromethane phenyl)imidazole[4,5‐f][1,10]phenanthroline), exhibited novel anticancer activity against human cancer cell lines, but with less toxicity to a human normal cell line. The results of flow cytometry and caspase activities analysis indicated that the 2 a‐induced growth inhibition against MG‐63 osteosarcoma cells was mainly caused by mitochondria‐mediated apoptosis. DNA fragmentation and nuclear condensation as detected by TUNEL–DAPI co‐staining further confirmed 2 a‐induced apoptotic cell death. Further, fluorescence imaging revealed that ruthenium(II) polypyridyl complexes could target mitochondria to induce mitochondrial fragmentation, accompanied by depletion of mitochondrial membrane potential. Taken together, these findings suggest a potential application of theses ruthenium(II) complexes in the treatment of cancers.
Heteronuclear Cross‐Relaxation Effects in the NMR Spectroscopy of Hyperpolarized Targets
Authors: Donovan Kevin J. , Lupulescu Adonis , Frydman Lucio 
Published: January 2014

AbstractDissolution dynamic nuclear polarization (DNP) enables high‐sensitivity solution‐phase NMR experiments on long‐lived nuclear spin species such as 15N and 13C. This report explores certain features arising in solution‐state 1H NMR upon polarizing low‐γ nuclear species. Following solid‐state hyperpolarization of both 13C and 1H, solution‐phase 1H NMR experiments on dissolved samples revealed transient effects, whereby peaks arising from protons bonded to the naturally occurring 13C nuclei appeared larger than the typically dominant 12C‐bonded 1H resonances. This enhancement of the satellite peaks was examined in detail with respect to a variety of mechanisms that could potentially explain this observation. Both two‐ and three‐spin phenomena active in the solid state could lead to this kind of effect; still, experimental observations revealed that the enhancement originates from 13C→1H polarization‐transfer processes active in the liquid state. Kinetic equations based on modified heteronuclear cross‐relaxation models were examined, and found to well describe the distinct patterns of growth and decay shown by the 13C‐bound 1H NMR satellite resonances. The dynamics of these novel cross‐relaxation phenomena were determined, and their potential usefulness as tools for investigating hyperpolarized ensembles and for obtaining enhanced‐sensitivity 1H NMR traces was explored.
Phosphatation of Zeolite H‐ZSM‐5: A Combined Microscopy and Spectroscopy Study
Authors: van der Bij Hendrik E. , Aramburo Luis R. , Arstad Bjørnar , Dynes James J. , Wang Jian , Weckhuysen Bert M. 
Published: January 2014

AbstractA variety of phosphated zeolite H‐ZSM‐5 samples are investigated by using a combination of Fourier transfer infrared (FTIR) spectroscopy, single pulse 27Al, 29Si, 31P, 1H‐31P cross polarization (CP), 27Al‐31P CP, and 27Al 3Q magic angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, scanning transmission X‐ray microscopy (STXM) and N2 physisorption. This approach leads to insights into the physicochemical processes that take place during phosphatation. Direct phosphatation of H‐ZSM‐5 promotes zeolite aggregation, as phosphorus does not penetrate deep into the zeolite material and is mostly found on and close to the outer surface of the zeolite, acting as a glue. Phosphatation of pre‐steamed H‐ZSM‐5 gives rise to the formation of a crystalline tridymite AlPO4 phase, which is found in the mesopores of dealuminated H‐ZSM‐5. Framework aluminum species interacting with phosphorus are not affected by hydrothermal treatment. Dealuminated H‐ZSM‐5, containing AlPO4, retains relatively more framework Al atoms and acid sites during hydrothermal treatment than directly phosphated H‐ZSM‐5.
Joint channel assignment and routing in multiradio multichannel wireless mesh networks with directional antennas
Authors: Sadeghianpour Nasrin , Chuah Teong Chee , Tan Su Wei 
Published: January 2014

SummaryThe aggregate capacity of a wireless mesh network (WMN) is severely affected by interflow interference. In this paper, we propose a network architecture that incorporates directional antennas with multiple orthogonal channels to effectively enhance the performance of WMNs. First, a sectored connectivity graph is introduced to model multiradio multichannel WMNs with directional antennas. Next we formulate the topology design, directional interface assignment, channel allocation, and routing mathematically as a mixed integer linear programming problem. This problem is solved using an iterated local search algorithm to obtain optimized network resource allocation. Simulation results indicate that the proposed architecture can achieve higher packet delivery ratio while providing better network fairness. Copyright © 2014 John Wiley & Sons, Ltd.
Microwave‐Assisted Synthesis of Substituted Pyrrolo[2,3‐d]pyrimidines
Authors: Prieur Vanessa , Rubio‐Martínez Jaime , Font‐Bardia Mercè , Guillaumet Gérald , Pujol M. Dolors 
Published: January 2014

AbstractA new synthetic route to triaryl pyrrolo[2,3‐d]pyrimidines from common 4,6‐dichloropyrimidine has been developed. The triarylated compounds are synthesized by three cross‐coupling reactions using three different catalysts. The introduction of a C‐6 aryl group was achieved in a two‐step process under Sonogashira conditions [Pd(dba)2/CuI] followed by intramolecular cyclization, and application of Suzuki–Miyaura conditions [Pd(PPh3)4; PdCl2(PPh3)2] led to C‐4 and C‐5 diarylation. This sequence allows a flexible synthetic approach to highly arylated pyrrolopyrimidines containing different aryl groups.
Organylzinc Chalcogenolate Promoted Michael‐Type Addition of α,β‐Unsaturated Carbonyl Compounds
Authors: Lóren Nunes Vanessa , de Oliveira Ingryd Cristina , Soares do Rêgo Barros Olga 
Published: January 2014

AbstractWe present the chemo‐, regio‐, and stereoselective synthesis of vinyl chalcogenide compounds promoted by organylzinc chalcogenolates. In this protocol, reductive cleavage of diorganyl dichalcogenide bonds by the Zn/NH4OH system led to organylzinc chalcogenolates. The reaction was performed with propiolic acids and esters and afforded β‐organochalcogenacrylic acids and esters under mild basic conditions. The stereochemistry corresponded to anti‐Markovnikov addition of the organyl chalcogenolate constituents across the triple bond.
N‐Benzoyl‐L‐Threonine‐Isopropyl‐Ester‐Mediated Crystallization‐Induced Dynamic Resolution of α‐Bromo Arylacetates for the Asymmetric Synthesis of α‐Thio and α‐Oxy Arylacetates
Authors: Park Kon Ji , Kim Yelim , Lee Myung‐su , Park Yong Sun 
Published: January 2014

AbstractN‐Benzoyl‐L‐threonine‐isopropyl‐ester‐mediated crystallization‐induced dynamic resolution (CIDR) of configurationally labile α‐bromo arylacetates has been investigated. The CIDR was successfully used for the asymmetric preparation of these compounds with up to 98:2 dr, under solution and solvent‐free conditions. Subsequent nucleophilic substitution reactions with sulfur and oxygen nulceophiles gave α‐thio and α‐oxy arylacetates with up to 98:2 dr. The method was further developed for the preparation of highly enantioenriched 2‐phenylthio‐2‐arylethanols with up to 97:3 er, and 1,4‐benzoxazin‐3‐ones with up to 94:6 er.
Tuberculosis drug discovery in the post‐post‐genomic era
Authors: Lechartier Benoit , Rybniker Jan , Zumla Alimuddin , Cole Stewart T 
Published: January 2014

AbstractThe expectation that genomics would result in new therapeutic interventions for infectious diseases remains unfulfilled. In the post‐genomic era, the decade immediately following the availability of the genome sequence of Mycobacterium tuberculosis, tuberculosis (TB) drug discovery relied heavily on the target‐based approach but this proved unsuccessful leading to a return to whole cell screening. Genomics underpinned screening by providing knowledge and many enabling technologies, most importantly whole genome resequencing to find resistance mutations and targets, and this resulted in a selection of leads and new TB drug candidates that are reviewed here. Unexpectedly, many new targets were found to be ‘promiscuous’ as they were inhibited by a variety of different compounds. In the post‐post‐genomics era, more advanced technologies have been implemented and these include high‐content screening, screening for inhibitors of latency, the use of conditional knock‐down mutants for validated targets and siRNA screens. In addition, immunomodulation and pharmacological manipulation of host functions are being explored in an attempt to widen our therapeutic options.
HOW IS DISASTER AID ALLOCATED WITHIN POOR COMMUNITIES? RISK SHARING AND SOCIAL HIERARCHY
Authors: Takasaki Yoshito 
Published: January 2014

AbstractHow disaster aid is allocated within poor communities is little understood. Using original post‐disaster survey data in rural Fiji that capture household‐level traditional kin status, cyclone damage and aid allocations over post‐disaster phases, this paper demonstrates that allocations are driven by informal risk‐sharing institutions and social hierarchies. On one hand, in response to a disaster with moderate severity, private risk sharing can strongly make up limited aid, making targeting aid on damage appear weak as a result. On the other hand, local elites can dominate not only aid allocation for given damage but also the targeting on damage. Copyright © 2014 John Wiley & Sons, Ltd.
Die deutsche Braunkohlenindustrie im Jahr 2012
Authors: Maaßen Uwe , Schiffer Hans‐Wilhelm 
Published: January 2014

Abstract185,4 Mill. t Braunkohle hat die deutsche Braunkohlenindustrie hat im Jahr 2012 gefördert. Dies entspricht einem Energiegehalt von 56,1 Mill. t SKE. Die Braunkohlenförderung deckt damit rund 12 % des gesamten inländischen Energiebedarfs. Der vorliegende Beitrag gibt einen Überblick über den Braunkohlenbergbau sowie die Verwendung von Braunkohle und fasst die aktuellen Entwicklungen auf den Gebieten der Braunkohlenverstromung und stofflichen Verwertung zusammen.The German lignite industry in 2012185.4 mill. t of lignite were extracted by the German lignite industry in 2012. This corresponds to an energy content of 56.1 mill. t SKE (coal units). Lignite extraction thus covers about 12 % of total German energy demand. The current article gives an overview of the mining and applications of lignite and summarises current developments in the areas of electricity generation and other applications of lignite.
125 Jahre Staatlicher Geologischer Dienst in Baden
Authors: Watzel Ralph 
Published: January 2014

AbstractAm 21. Dezember 2013 jährt sich die formale Gründung der Großherzoglich badischen geologischen Landesanstalt durch Großherzog Friedrich I. von Baden zum 125. Mal. Sie war der erste Staatliche Geologische Dienst auf der Fläche des heutigen Bundeslands Baden‐Württemberg. Am 7. August 1903 folgte der Gründungserlass der Geologischen Abteilung beim Statistischen Landesamt des Königreichs Württemberg.
Molecular and genetic diversity in the metastatic process of melanoma
Authors: Harbst Katja , Lauss Martin , Cirenajwis Helena , Winter Christof , Howlin Jillian , Törngren Therese , Kvist Anders , Nodin Björn , Olsson Eleonor , Häkkinen Jari , Jirström Karin , Staaf Johan , Lundgren Lotta , Olsson Håkan , Ingvar Christian , Gruvberger‐Saal Sofia K , Saal Lao H , Jönsson Göran 
Published: January 2014

AbstractDiversity between metastatic melanoma tumours in individual patients is known; however, the molecular and genetic differences remain unclear. To examine the molecular and genetic differences between metastatic tumours, we performed gene‐expression profiling of 63 melanoma tumours obtained from 28 patients (two or three tumours/patient), followed by analysis of their mutational landscape, using targeted deep sequencing of 1697 cancer genes and DNA copy number analysis. Gene‐expression signatures revealed discordant phenotypes between tumour lesions within a patient in 50% of the cases. In 18 of 22 patients (where matched normal tissue was available), we found that the multiple lesions within a patient were genetically divergent, with one or more melanoma tumours harbouring 'private' somatic mutations. In one case, the distant subcutaneous metastasis of one patient occurring 3 months after an earlier regional lymph node metastasis had acquired 37 new coding sequence mutations, including mutations in PTEN and CDH1. However, BRAF and NRAS mutations, when present in the first metastasis, were always preserved in subsequent metastases. The patterns of nucleotide substitutions found in this study indicate an influence of UV radiation but possibly also DNA alkylating agents. Our results clearly demonstrate that metastatic melanoma is a molecularly highly heterogeneous disease that continues to progress throughout its clinical course. The private aberrations observed on a background of shared aberrations within a patient provide evidence of continued evolution of individual tumours following divergence from a common parental clone, and might have implications for personalized medicine strategies in melanoma treatment. Published by John Wiley & Sons, Ltd. www.pathsoc.org.uk
Lower Extremity Muscle Activation During Functional Exercises in Patients With and Without Chronic Ankle Instability
Authors: Feger Mark A. , Donovan Luke , Hart Joseph M. , Hertel Jay 
Published: January 2014

ObjectiveTo determine whether individuals with chronic ankle instability (CAI) exhibit altered neuromuscular control as demonstrated by surface electromyography (EMG) amplitudes compared with healthy controls during single‐limb eyes‐closed balance, Star Excursion Balance Test, forward lunge, and lateral hop exercises.DesignA cross‐sectional laboratory study.SettingA research laboratory.ParticipantsFifteen young adults with CAI and 15 healthy controls.InterventionsThe subjects performed functional exercises while surface EMG signals were recorded from the tibialis anterior, peroneus longus, lateral gastrocnemius, rectus femoris, biceps femoris, and gluteus medius.Main Outcome MeasurementsSurface EMG amplitudes (root mean square area) for each muscle, muscles of the shank (distal 3 muscles), muscles of the thigh (proximal 3 muscles), and total muscle activity (all 6 muscles) of the lower extremity were analyzed and compared between the groups.ResultsIndividuals with CAI demonstrated significantly less EMG activity in the muscles of the lower extremity during all 4 functional exercises. Effect sizes for significant differences between groups ranged from −0.75 to −1.08, none of which had 95% confidence intervals that crossed zero, which indicates moderate to large decreases in muscle activity in patients with CAI compared with healthy controls.ConclusionsPatients with CAI demonstrated decreased muscle activity of ankle, knee, and hip musculature during common functional rehabilitative tasks. Clinicians may benefit from implementing functional exercises for patients with CAI that target both distal and proximal muscles of the lower extremity.
Dust grain surface potential in a non-Maxwellian dusty plasma with negative ions
Authors: ABID A. A. , ALI S. , MUHAMMAD R. 
Published: January 2014

AbstractDust charging processes involving the collection of electrons and positive/negative ions in a non-equilibrium dusty plasma are revisited by employing the power-law kappa (κ)-distribution function. In this context, the current balance equation is solved to obtain dust grain surface potential in the presence of negative ions. Numerically, it is found that plasma parameters, such as the κ spectral index, the negative ion-to-electron temperature ratio (γ), the negative–positive ion number density ratio (α), and the negative ion streaming speed (U0) significantly modify the dust grain potential profiles. In particular, for large kappa values, the dust grain surface potential reduces to the Maxwellian case, and at lower kappa values the magnitude of the negative dust surface potential increases. An increase in γ and U0 leads to the enhancement of the magnitude of the dust grain surface potential, while α leads to an opposite effect. The relevance of present results to low-temperature laboratory plasmas is discussed.
Novel inhibitors of the Plasmodium falciparum electron transport chain
Authors: STOCKS P. A. , BARTON V. , ANTOINE T. , BIAGINI G. A. , WARD S. A. , O'NEILL P. M. 
Published: January 2014

SUMMARYDue to an increased need for new antimalarial chemotherapies that show potency against Plasmodium falciparum, researchers are targeting new processes within the parasite in an effort to circumvent or delay the onset of drug resistance. One such promising area for antimalarial drug development has been the parasite mitochondrial electron transport chain (ETC). Efforts have been focused on targeting key processes along the parasite ETC specifically the dihydroorotate dehydrogenase (DHOD) enzyme, the cytochrome bc1 enzyme and the NADH type II oxidoreductase (PfNDH2) pathway. This review summarizes the most recent efforts in antimalarial drug development reported in the literature and describes the evolution of these compounds.
A Multiscale Model of Interleukin‐6–Mediated Immune Regulation in Crohn's Disease and Its Application in Drug Discovery and Development
Authors: Dwivedi G , Fitz L , Hegen M , Martin SW , Harrold J , Heatherington A , Li C 
Published: January 2014

In this study, we have developed a multiscale systems model of interleukin (IL)‐6–mediated immune regulation in Crohn's disease, by integrating intracellular signaling with organ‐level dynamics of pharmacological markers underlying the disease. This model was linked to a general pharmacokinetic model for therapeutic monoclonal antibodies and used to comparatively study various biotherapeutic strategies targeting IL‐6–mediated signaling in Crohn's disease. Our work illustrates techniques to develop mechanistic models of disease biology to study drug–system interaction. Despite a sparse training data set, predictions of the model were qualitatively validated by clinical biomarker data from a pilot trial with tocilizumab. Model‐based analysis suggests that strategies targeting IL‐6, IL‐6Rα, or the IL‐6/sIL‐6Rα complex are less effective at suppressing pharmacological markers of Crohn's than dual targeting the IL‐6/sIL‐6Rα complex in addition to IL‐6 or IL‐6Rα. The potential value of multiscale system pharmacology modeling in drug discovery and development is also discussed.CPT Pharmacometrics Syst. Pharmacol. (2014) 3, e89; doi:10.1038/psp.2013.64; advance online publication 8 January 2014
In situ environment rather than substrate type dictates microbial community structure of biofilms in a cold seep system
Authors: Lee On On , Wang Yong , Tian Renmao , Zhang Weipeng , Shek Chun Shum , Bougouffa Salim , Al-Suwailem Abdulaziz , Batang Zenon B. , Xu Wei , Wang Guang Chao , Zhang Xixiang , Lafi Feras F. , Bajic Vladmir B. , Qian Pei-Yuan 
Published: January 2014

AbstractUsing microscopic and molecular techniques combined with computational analysis, this study examined the structure and composition of microbial communities in biofilms that formed on different artificial substrates in a brine pool and on a seep vent of a cold seep in the Red Sea to test our hypothesis that initiation of the biofilm formation and spreading mode of microbial structures differs between the cold seep and the other aquatic environments. Biofilms on different substrates at two deployment sites differed morphologically, with the vent biofilms having higher microbial abundance and better structural features than the pool biofilms. Microbes in the pool biofilms were more taxonomically diverse and mainly composed of various sulfate-reducing bacteria whereas the vent biofilms were exclusively dominated by sulfur-oxidizing Thiomicrospira. These results suggest that the redox environments at the deployment sites might have exerted a strong selection on microbes in the biofilms at two sites whereas the types of substrates had limited effects on the biofilm development.
Comparable Stability of Hoogsteen and Watson–Crick Base Pairs in Ionic Liquid Choline Dihydrogen Phosphate
Authors: Tateishi-Karimata Hisae , Nakano Miki , Sugimoto Naoki 
Published: January 2014

AbstractThe instability of Hoogsteen base pairs relative to Watson–Crick base pairs has limited biological applications of triplex-forming oligonucleotides. Hydrated ionic liquids (ILs) provide favourable environments for a wide range of chemical reactions and are known to impact the stabilities of Watson–Crick base pairs. We found that DNA triplex formation was significantly stabilized in hydrated choline dihydrogen phosphate as compared with an aqueous buffer at neutral pH. Interestingly, the stability of Hoogsteen base pairs was found to be comparable with that of Watson–Crick base pairs in the hydrated IL. Molecular dynamics simulations of a DNA triplex in the presence of choline ions revealed that the DNA triplex was stabilized because of the binding of choline ion around the third strand in the grooves. Our finding will facilitate the development of new DNA materials. Our data also indicate that triplex formation may be stabilized inside cells where choline ions and their derivatives are abundant in vivo.
Prediction of 1P Rydberg energy levels of beryllium based on calculations with explicitly correlated Gaussians
Authors: Bubin Sergiy , Adamowicz Ludwik 
Published: January 2014

Benchmark variational calculations are performed for the seven lowest 1s22s np (1P), n = 2…8, states of the beryllium atom. The calculations explicitly include the effect of finite mass of 9Be nucleus and account perturbatively for the mass-velocity, Darwin, and spin-spin relativistic corrections. The wave functions of the states are expanded in terms of all-electron explicitly correlated Gaussian functions. Basis sets of up to 12 500 optimized Gaussians are used. The maximum discrepancy between the calculated nonrelativistic and experimental energies of 1s22s np (1P) →1s22s2 (1S) transition is about 12 cm−1. The inclusion of the relativistic corrections reduces the discrepancy to bellow 0.8 cm−1.