bluuebunny/crossref_metadata_2025 huggingface dataset:
Medical and Clinical Pathology Pre-Screening Visit and Enrolment Seasonal Variability in Healthy Volunteers
Authors: Yahya Murad  , Zaher A. Radi
Published: September 2014

In the pharmaceutical industry, selection of healthy volunteers is one of the foundations in phase I clinical trials and is a difficult and costly process. The objectives of this study were to evaluate the seasonal variability in recruiting healthy volunteers and examine the value of utilizing a pre-screen visit for healthy volunteers to generate a database pool that will be used in the routine screening process of phase I clinical research studies. We retrospectively studied a total of 1115 male and female volunteers who were scheduled for a medical and clinical pathology pre-screen visit over a one year period. Written consents were obtained from all individuals who participated in the study. Medical pre-screen visit included a full medical history and examination and electrocardiogram and clinical pathology (clinical chemistry, hematology and urinalysis). There was apparent seasonal variability in the participation of individuals in the pre-screen visit. Increased values of clinical chemistry values such as alanine aminotransferase and aspartate aminotransferase accounted for the majority of the clinically relevant increased values. Increased values of WBC’s and both platelets and mean corpuscular volume accounted for the lowest values. In urinalysis, the most prevalent abnormal values were increased WBC’s and red blood cells. No apparent differences were seen between sexes.Conducting medical and clinical pathology pre-screening visit is important as a source for healthy volunteer database pool to participate in phase I trials.
Coding of stimulus strength via analog calcium signals in Purkinje cell dendrites of awake mice
Authors: Najafi Farzaneh , Giovannucci Andrea , Wang Samuel S-H , Medina Javier F
Published: September 2014

The climbing fiber input to Purkinje cells acts as a teaching signal by triggering a massive influx of dendritic calcium that marks the occurrence of instructive stimuli during cerebellar learning. Here, we challenge the view that these calcium spikes are all-or-none and only signal whether the instructive stimulus has occurred, without providing parametric information about its features. We imaged ensembles of Purkinje cell dendrites in awake mice and measured their calcium responses to periocular airpuffs that serve as instructive stimuli during cerebellar-dependent eyeblink conditioning. Information about airpuff duration and pressure was encoded probabilistically across repeated trials, and in two additional signals in single trials: the synchrony of calcium spikes in the Purkinje cell population, and the amplitude of the calcium spikes, which was modulated by a non-climbing fiber pathway. These results indicate that calcium-based teaching signals in Purkinje cells contain analog information that encodes the strength of instructive stimuli trial-by-trial.
Interaction of Active MMIC with Package/Housing -Theory, Analysis and Measurement
Authors: Sarvaiya A. , Gupta S. , Ghodgaonkar D.
Published: September 2014

This paper presents enclosure effect comprehensive by 3D Electromagnetic modeling, simulation and measurement of active MMIC with Package/housing. When put inside a test box or package with a cavity, MMIC shows significant deviation from it RFOW measurement data. Cavity resonance’s adverse effects are analyzed by Eigen mode solver using CST Microwave Studio and RFOW measurement and in test box data is matched by simulating package/house with the best suited RF absorbers.
Synthesis and Characterization of Benzylidene Acetal–Type Bridged Nucleic Acids (BA‐BNA)
Authors: Kodama Tetsuya , Morihiro Kunihiko , Obika Satoshi
Published: September 2014

Benzylidene acetal‐type bridged nucleic acids (BA‐BNAs) have a bridged structure that cleaves upon exposure to appropriate external stimuli, which induces changes in oligonucleotide properties. In particular, duplex stability and resistance to enzymatic digestion vary depending on the incorporation number and/or position of BA‐BNAs. This unit describes the synthesis of some types of BA‐BNA thymine nucleosides and the corresponding BA‐BNA phosphoramidites, as well as the incorporation of BA‐BNA nucleosides into oligonucleotides. Moreover, typical procedures that induce property changes in each BA‐BNA are described. 6‐Nitroveratrylidene and 2‐nitrobenzylidene acetal type BA‐BNA respond to photoirradiation and subsequent thiol treatment. Benzylidene and 4‐nitrobenzylidene acetal type BA‐BNAs respond to acids and reducing agents, respectively. Every BA‐BNA is derivatized into 4′‐C‐hydroxymethyl RNA by hydrolysis of the acetal‐bridged structure. Curr. Protoc. Nucleic Acid Chem. 58:1.31.1‐1.31.22. © 2014 by John Wiley & Sons, Inc.
Design and Synthesis of Triazolyl‐Donor/Acceptor Unnatural Nucleosides and Oligonucleotide Probes Containing Triazolyl‐Phenanthrene Nucleoside
Authors: Bag Subhendu Sekhar , Talukdar Sangita , Das Suman Kalyan
Published: September 2014

In the context of abasic DNA or DNA duplex stabilization, several unnatural nucleosidic/non‐nucleosidic base surrogates have been reported. Toward this end, we have designed and synthesized triazolyl‐aromatic donor chomophores as unnatural nucleoside analogs. These modifications display markedly higher thermal stabilization of abasic DNA duplex in comparison to the stabilization offered by other nucleoside/non‐nucleoside base surrogates reported in the literature. The same oligonucleotide probe containing triazolylphenanthrene nucleotide also offers very good stability of the self‐pair duplex via π‐π stacking interaction and hetero‐pair duplex via charge transfer interaction when paired against triazolyl acceptor aromatic nucleoside. Moreover, the probe in the reverse sequence containing triazolylphenanthrene nucleotide has shown FRET efficiency in a chimeric DNA duplex. The triazolyl nucleotides would expectedly show stability toward exonuclease activity. This unit describes protocols for chemical synthesis of unnatural triazolyl nucleosides and one oligonucleotide probe. The unit also provides a summary of various thermal and photophysical applications of triazolylphenantherene‐containing oligonucleotides. Curr. Protoc. Nucleic Acid Chem. 58:1.32.1‐1.32.27. © 2014 by John Wiley & Sons, Inc.
BEDTools: The Swiss‐Army Tool for Genome Feature Analysis
Authors: Quinlan Aaron R.
Published: September 2014

Technological advances have enabled the use of DNA sequencing as a flexible tool to characterize genetic variation and to measure the activity of diverse cellular phenomena such as gene isoform expression and transcription factor binding. Extracting biological insight from the experiments enabled by these advances demands the analysis of large, multi‐dimensional datasets. This unit describes the use of the BEDTools toolkit for the exploration of high‐throughput genomics datasets. Several protocols are presented for common genomic analyses, demonstrating how simple BEDTools operations may be combined to create bespoke pipelines addressing complex questions. Curr. Protoc. Bioinform. 47:11.12.1‐11.12.34. © 2014 by John Wiley & Sons, Inc.
Bayesian inference of a lake water quality model by emulating its posterior density
Authors: Dietzel A. , Reichert P.
Published: September 2014

We use a Gaussian stochastic process emulator to interpolate the posterior probability density of a computationally demanding application of the biogeochemical‐ecological lake model BELAMO to accelerate statistical inference of deterministic model and error model parameters. The deterministic model consists of a mechanistic description of key processes influencing the mass balance of nutrients, dissolved oxygen, organic particles, and phytoplankton and zooplankton in the lake. This model is complemented by a Gaussian stochastic process to describe the remaining model bias and by Normal, independent observation errors. A small subsample of the Markov chain representing the posterior of the model parameters is propagated through the full model to get model predictions and uncertainty estimates. We expect this approximation to be more accurate at only slightly higher computational costs compared to using a Normal approximation to the posterior probability density and linear error propagation to the results as we did in an earlier paper. The performance of the two techniques is compared for a didactical example as well as for the lake model. As expected, for the didactical example, the use of the emulator led to posterior marginals of the model parameters that are closer to those calculated by Markov chain simulation using the full model than those based on the Normal approximation. For the lake model, the new technique proved applicable without an excessive increase in computational requirements, but we faced challenges in the choice of the design data set for emulator calibration. As the posterior is a scalar function of the parameters, the suggested technique is an alternative to the emulation of a potentially more complex, structured output of the simulation model that allows for the use of a less case‐specific emulator. This is at the cost that still the full model has to be used for prediction (which can be done with a smaller, approximately independent subsample of the Markov chain).
With or against the tide: The influence of bed form asymmetry on the formation of macroturbulence and suspended sediment patterns
Authors: Kwoll E. , Becker M. , Winter C.
Published: September 2014

This study examines tide‐dependent variations in the formation and dynamics of suspended sediment patterns coupled to mean flow and turbulence above asymmetric bed forms. In the Danish Knudedyb inlet, very large primary bed forms remain ebb‐oriented during a tidal cycle while smaller superimposed bed forms reverse direction with each tidal phase. Hydroacoustic in situ observations reveal pronounced differences in suspended sediment transport patterns between tidal phases caused by the relative orientation of primary bed forms and the mean tidal flow and flow unsteadiness during a single tidal phase. When flow and primary bed form orientation are aligned, water‐depth‐scale macroturbulence develops in the bed form lee‐sides in the presence of flow separation. Macroturbulent flow structures occur at high flow stages and are coupled to increased amounts of sediment in suspension. When flow and bed form orientation are opposed no evidence of flow separation associated with primary bed forms is found. Sediment‐laden macroturbulence at high flow velocities is of a smaller scale and attributed to the superimposed secondary bed forms. The flow structures are advected along the primary bed form stoss‐side (temporary hydraulic lee‐side). The steep primary bed form lee‐side (temporary hydraulic stoss‐side) however, limits transport capabilities beyond the scale of primary bed forms.
Multiobjective optimization of cluster‐scale urban water systems investigating alternative water sources and level of decentralization
Authors: Newman J. P. , Dandy G. C. , Maier H. R.
Published: September 2014

In many regions, conventional water supplies are unable to meet projected consumer demand. Consequently, interest has arisen in integrated urban water systems, which involve the reclamation or harvesting of alternative, localized water sources. However, this makes the planning and design of water infrastructure more difficult, as multiple objectives need to be considered, water sources need to be selected from a number of alternatives, and end uses of these sources need to be specified. In addition, the scale at which each treatment, collection, and distribution network should operate needs to be investigated. In order to deal with this complexity, a framework for planning and designing water infrastructure taking into account integrated urban water management principles is presented in this paper and applied to a rural greenfield development. Various options for water supply, and the scale at which they operate were investigated in order to determine the life‐cycle trade‐offs between water savings, cost, and GHG emissions as calculated from models calibrated using Australian data. The decision space includes the choice of water sources, storage tanks, treatment facilities, and pipes for water conveyance. For each water system analyzed, infrastructure components were sized using multiobjective genetic algorithms. The results indicate that local water sources are competitive in terms of cost and GHG emissions, and can reduce demand on the potable system by as much as 54%. Economies of scale in treatment dominated the diseconomies of scale in collection and distribution of water. Therefore, water systems that connect large clusters of households tend to be more cost efficient and have lower GHG emissions. In addition, water systems that recycle wastewater tended to perform better than systems that captured roof‐runoff. Through these results, the framework was shown to be effective at identifying near optimal trade‐offs between competing objectives, thereby enabling informed decisions to be made when planning water systems for greenfield developments.
Enabling Climate and Energy Literacy: A Shared Effort
Authors: Ledley Tamara Shapiro , Gold Anne U. , Niepold Frank
Published: September 2014

Climate and energy sciences are rapidly evolving with respect to both knowledge and available technology. At the same time, citizens of all ages need accurate, up‐to‐date information, knowledge of the sciences, and analytical skills to make responsible decisions and long‐term plans regarding these challenging topics.
LEGO® Set Features Women Scientists
Authors: McCarter Tricia
Published: September 2014

Earth and space scientists: You've just been immortalized in LEGO® toys.
Dingwell, Head Receive 2013 N. L. Bowen Award: Response
Authors: Dingwell Donald Bruce
Published: September 2014

Thank you, Kelly!
March for Climate in New York
Authors: McCarter Tricia
Published: September 2014

On Sunday, 21 September, the People's Climate March will be held in New York City to raise awareness about climate change. With world leaders gathering in that city on 23 September for the United Nations Climate Summit, the march aims to mobilize scientists, activists, community leaders, and members of the public who care about climate change and galvanize action about this important issue.
A comparison of the effects of CIR‐ and CME‐induced geomagnetic activity on thermospheric densities and spacecraft orbits: Statistical studies
Authors: Chen Guang‐ming , Xu Jiyao , Wang Wenbin , Burns Alan. G.
Published: September 2014

Enhanced energy input from the magnetosphere to the upper atmosphere during geomagnetic storms has a profound effect on thermospheric density and consequently near‐Earth satellite orbit decay. These geomagnetic storms are caused by two different processes. The first is coronal mass ejections (CMEs) and the second is corotating interaction regions (CIRs). CME‐driven storms are characterized by large maximum energy input but relatively short duration, whereas CIR‐driven storms have relatively small maximum energy input but are of a considerably longer duration. In this paper we carried out a statistical study to assess the relative importance of each kind of storm to satellite orbital decay. The results demonstrate that CIR storms have a slightly larger effect on total orbital decay than CME storms do in a statistical sense. During the declining phase and the minimum years of a solar cycle, CIR storms occur frequently and quasiperiodically. These storms have a large effect on thermospheric densities and satellite orbits because of their relatively long duration. Thus, it is important to fully understand their behavior and impact.
Dynamical effects during compaction band formation affecting their spatial periodicity
Authors: Cecinato Francesco , Gajo Alessandro
Published: September 2014

Compaction bands (CBs) are responsible for significant anisotropy alterations of permeability in geological materials; hence, understanding their formation conditions appears of key importance to all applications involving fluid extraction/injection from/into the ground. While most of the available models to understand CB formation are focused on interpreting the onset of a single CB, little effort has been so far dedicated to understand the documented periodicity of CBs. In this paper, the role of dynamical effects in inducing the post onset evolution of CBs is analyzed by means of a dedicated model for porous media with compressible constituents, with reference to a horizontal layer of sandy, water‐saturated material. Elastic waves are generated as a first CB occurs due to sudden, localized volumetric collapse. If the waves are reflected at the interface with a softer material or with a previously formed CB, they produce significant local effective stress concentrations, which can promote the formation of further CBs in a cascade fashion, according to a regular geometric pattern. The spatial distribution of dynamically generated CBs, as well as the extent of the phenomenon, depends on the geometry of the domain and on the material's permeability. Sensitivity analysis is also performed to assess the key properties that promote dynamical CB in situ formation, identifying as the most influential conditions large stratum stiffness (increasing with depth) and the presence of softer layers. In contrast, the presence of less permeable and/or stiffer layers is not believed to play a major role in the proposed mechanism.
A dynamic watershed model for determining the effects of transient storage on nitrogen export to rivers
Authors: Chen Dingjiang , Hu Minpeng , Dahlgren Randy A.
Published: September 2014

Legacy anthropogenic nitrogen (N) has been suggested as a major cause for increasing riverine N exports despite significant declines in anthropogenic N inputs in many regions. However, little quantitative knowledge exists concerning the contribution of the legacy N pool to riverine N export. This study developed a dynamic watershed N delivery model to address the role of transient storage of anthropogenic N inputs on riverine N flux. Employing simple mass balance and equivalent substitution rules, the model expresses the transient storage of legacy N mass with a term that combines the previous one year's riverine total N (TN) flux, relevant explanatory variables, and unknown parameters, enabling us to inversely calibrate the model parameters from measurable variables using Bayesian statistics. The model efficacy was demonstrated through application to the Yong'an River watershed in eastern China based on a 31 year record (1980–2010) of riverine TN fluxes. The model can quantify annual transient storage of legacy N and its resulting contribution to annual riverine N flux. The model also allows partitioning of the complete long‐term mass balance for the fate (e.g., transient storage, riverine export, and loss/retention by denitrification, biomass uptake and wood product export) of annual anthropogenic N inputs. To further improve the model, various N input‐output processes can be specified and long‐term measurements of N fates are required to further verify the model results. This study demonstrates the need to consider transient storage effects as an improvement to current watershed models and for developing and assessing N pollution control measures.
Quantification of Protein Kinase Enzymatic Activity in Unfractionated Cell Lysates Using CSox‐Based Sensors
Authors: Beck Jon R. , Peterson Laura B. , Imperiali Barbara , Stains Cliff I.
Published: September 2014

Defining perturbations in protein kinase activity within biological samples can provide insight into disease mechanisms as well as potential targets for drug development. In this article, we present a method that utilizes a phosphorylation‐sensitive amino acid, termed CSox, to afford kinase‐selective biosensors capable of reporting on enzymatic activity directly in biological samples. These sensors produce an increase in fluorescence in response to phosphorylation of an amino acid residue adjacent to CSox. Probes can be designed for either serine/threonine or tyrosine kinases, and analysis can be performed using standard fluorescence equipment. The procedures provided herein represent our optimized protocols for the design, validation, and application of CSox‐based protein kinase activity sensors. Curr. Protoc. Chem. Biol. 6:135‐156 © 2014 by John Wiley & Sons, Inc.
Tandem Synthesis of Polysubstituted Pyridines via the Indium(III)‐Triflate‐Catalyzed Cycloaddition/Oxidative Aromatization of Blaise Reaction Intermediates with α,β‐Unsaturated Ketones
Authors: Xuan Zi , Rathwell Kris , Lee Sang‐gi
Published: September 2014

A tandem one‐pot method for the construction of polysubstituted pyridines with complete control of the substitution pattern has been developed. The zinc bromide β‐enamino ester intermediates of the Blaise reaction of simple nitriles with a Reformatsky reagent undergo Michael addition with conjugated ketones in the presence of a catalytic amount of In(OTf)3. Final intramolecular cyclization and oxidative aromatization yields polysubstituted pyridines in this tandem one‐pot cascade.
Lumineszenzsteigerung bei Lanthanoid‐dotierten aufkonvertierenden Nanopartikeln
Authors: Han Sanyang , Deng Renren , Xie Xiaoji , Liu Xiaogang
Published: September 2014

Es gibt ein großes Interesse an der Erforschung von Lanthanoid‐dotierten aufkonvertierenden Nanopartikeln aufgrund ihrer optischen Eigenschaften und ihrem breitgefächerten Anwendungspotential von der biologischen Bildgebung bis hin zur photodynamischen Therapie. Trotz der beachtlichen Fortschritte, die im letzten Jahrzehnt erzielt wurden, wird das Gebiet durch erhebliche experimentelle Probleme im Zusammenhang mit geringen Umwandlungswirkungsgraden der Aufkonversion behindert. Neuere experimentelle und theoretische Studien zu aufkonvertierenden Nanopartikeln führten jedoch zur Entwicklung mehrerer wirksamer Methoden zur Steigerung der Aufkonversionslumineszenz, die tiefgreifende Auswirkungen auf eine Reihe von Anwendungen haben könnten. In diesem Kurzaufsatz beschreiben wir die zugrundeliegenden Prinzipien der Steuerung der Energieübertragung über die Dotierung mit Lanthanoid, geben einen Überblick über die wesentlichen Fortschritte und die Hauptherausforderungen bei der Verbesserung der Aufkonversionslumineszenz und betrachten die voraussichtlichen Ausrichtungen der zukünftigen Forschung auf dem Gebiet.
X‐Ray Emission Spectroscopy: A Spectroscopic Measure for the Determination of NO Oxidation States in Fe–NO Complexes
Authors: Lu Tsai‐Te , Weng Tsu‐Chien , Liaw Wen‐Feng
Published: September 2014

Extensive study of the electronic structure of Fe‐NO complexes using a variety of spectroscopic methods was attempted to understand how iron controls the binding and release of nitric oxide. The comparable energy levels of NO π* orbitals and Fe 3d orbitals complicate the bonding interaction within FeNO complexes and puzzle the quantitative assignment of NO oxidation state. Enemark–Feltham notation, {Fe(NO)x}n, was devised to circumvent this puzzle. This 40‐year puzzle is revisited using valence‐to‐core X‐ray emission spectroscopy (V2C XES) in combination with computational study. DFT calculation establishes a linear relationship between ΔEσ2s*‐σ2p of NO and its oxidation state. V2C Fe XES study of FeNO complexes reveals the ΔEσ2s*‐σ2p of NO derived from NO σ2s*/σ2p→Fe1s transitions and determines NO oxidation state in FeNO complexes. Quantitative assignment of NO oxidation state will correlate the feasible redox process of nitric oxide and Fe‐nitrosylation biology.
Advances in Anion Supramolecular Chemistry: From Recognition to Chemical Applications
Authors: Evans Nicholas H. , Beer Paul D.
Published: September 2014

Since the start of this millennium, remarkable progress in the binding and sensing of anions has been taking place, driven in part by discoveries in the use of hydrogen bonding, as well as the previously under‐exploited anion–π interactions and halogen bonding. However, anion supramolecular chemistry has developed substantially beyond anion recognition, and now encompasses a diverse range of disciplines. Dramatic advance has been made in the anion‐templated synthesis of macrocycles and interlocked molecular architectures, while the study of transmembrane anion transporters has flourished from almost nothing into a rapidly maturing field of research. The supramolecular chemistry of anions has also found real practical use in a variety of applications such as catalysis, ion extraction, and the use of anions as stimuli for responsive chemical systems.
Palladium‐Catalyzed Annulation of Diarylamines with Olefins through CH Activation: Direct Access to N‐Arylindoles
Authors: Sharma Upendra , Kancherla Rajesh , Naveen Togati , Agasti Soumitra , Maiti Debabrata
Published: September 2014

A palladium‐catalyzed dehydrogenative coupling between diarylamines and olefins has been discovered for the synthesis of substituted indoles. This intermolecular annulation approach incorporates readily available olefins for the first time and obviates the need of any additional directing group. An ortho palladation, olefin coordination, and β‐migratory insertion sequence has been proposed for the generation of olefinated intermediate, which is found to produce the expected indole moiety.
Solid‐State Structure of a Li/F Carbenoid: Pentafluoroethyllithium
Authors: Waerder Benedikt , Steinhauer Simon , Neumann Beate , Stammler Hans‐Georg , Mix Andreas , Vishnevskiy Yury V. , Hoge Berthold , Mitzel Norbert W.
Published: September 2014

Lithium carbenoids are versatile compounds for synthesis owing to their intriguing ambiphilic behavior. Although this class of compounds has been known for several years, few solid‐state structures exist because of their high reactivity and often low thermal stability. Using cryo X‐ray techniques, we were now able to elucidate the first solid‐state structure of a Li/F alkyl carbenoid, pentafluoroethyllithium (LiC2F5), finally yielding a prototype for investigating structure—reactivity relationships for this class of molecules. The compound forms a diethyl ether‐solvated dimer bridged by a rare C–F–Li link. Complementary NMR spectroscopy studies in solution show dynamic processes and indicate rapid exchange of starting material and product. Theoretical investigations help to understand the formation of the observed unusual structural motif.
Efficient Access to Substituted Silafluorenes by Nickel‐Catalyzed Reactions of Biphenylenes with Et2SiH2
Authors: Breunig Jens Michael , Gupta Puneet , Das Animesh , Tussupbayev Samat , Diefenbach Martin , Bolte Michael , Wagner Matthias , Holthausen Max C. , Lerner Hans‐Wolfram
Published: September 2014

The reaction of biphenylene (1) with Et2SiH2 in the presence of [Ni(PPhMe2)4] results in the formation of a mixture of 2‐diethylhydrosilylbiphenyl [2(Et2HSi)] and 9,9,‐diethyl‐9‐silafluorene (3). Silafluorene 3 was isolated in 37.5 % and 2(Et2HSi) in 36.9 % yield. The underlying reaction mechanism was elucidated by DFT calculations. 4‐Methyl‐9,9‐diethyl‐9‐silafluorene (7) was obtained selectively from the [Ni(PPhMe2)4]‐catalyzed reaction of Et2SiH2 and 1‐methylbiphenylene. By contrast, no selectivity could be found in the Ni‐catalyzed reaction between Et2SiH2 and the biphenylene derivative that bears tBu substituents in the 2‐ and 7‐positions. Therefore, two pairs of isomers of tBu‐substituted silafluorenes and of the related diethylhydrosilylbiphenyls were formed in this reaction. However, a subsequent dehydrogenation of the diethylhydrosilylbiphenyls with Wilkinson’s catalyst yielded a mixture of 2,7‐di‐tert‐butyl‐9,9‐diethyl‐9‐silafluorene (8) and 3,6‐di‐tert‐butyl‐9,9‐diethyl‐9‐silafluorene (9). Silafluorenes 8 and 9 were separated by column chromatography.
Explicit and Iterative Methods for Solving the Matrix Equation AV + BW = EVF + C
Authors: Ramadan Mohamed A. , Bayoumi Ahmed M. E.
Published: September 2014

In this paper, we consider explicit and iterative methods for solving the Generalized Sylvester matrix equation AV + BW = EVF + C. Based on the use of Kronecker map and Sylvester sum some lemmas and theorems are stated and proved where explicit and iterative solutions are obtained. The proposed methods are illustrated by numerical example. The obtained results show that the methods are very neat and efficient.
Perfusion culture‐induced template‐assisted assembling of cell‐laden microcarriers is a promising route for fabricating macrotissues
Authors: Wang Xiu , Jiao Qingling , Zhang Songjie , Ye Zhaoyang , Zhou Yan , Tan Wen‐Song
Published: September 2014

Mass transfer limitation in conventional top‐down tissue engineering makes it impossible to fabricate large size viable tissue replacements. In the present study, we aimed at performing a systemic investigation of the assembling process in perfusion culture for fabricating centimeter‐scale macrotissues from cell‐laden microcarriers following a bottom‐up modular approach. Cells (human fibroblasts, human mesenchymal stem cells, or HepG2 cells) were seeded onto microcarriers (Cytopore‐2 or CultiSpher S) in spinner flasks and cultured for 14 days and subsequently transferred to a perfusion chamber for assembling. It was found that growth of different cells on different microcarriers varied and aggregation of cell‐laden microcarriers was favored with CultiSpher S. After perfusion culture for 14 days, while all microtissues could assemble into integral macrotissues, macrotissues of HepG2 cells were structurally most inferior and the assembling of cell‐laden CultiSpher S led to a significant shrinkage. By designing perfusion chamber and using agar‐based templates, tubular, disc, and alphabetic letter‐shaped macrotissues could be easily fabricated, suggesting template‐assisted assembling. Importantly, it was revealed that there existed both optimal perfusion culture time (21 days) and packing condition (1/4 compression) for the assembling of microtissues. This study lays a solid foundation for future applications of this microtissue assembling technique in tissue engineering.
Effect of laparoscopic splenectomy on portal haemodynamics in patients with liver cirrhosis and portal hypertension
Authors: Kawanaka H , Akahoshi T , Kinjo N , Iguchi T , Ninomiya M , Yamashita Y-I , Ikegami T , Yoshizumi T , Shirabe K , Maehara Y
Published: September 2014

Background

The effect of splenomegaly in patients with liver cirrhosis and portal hypertension is not fully understood. This study was designed to determine the effect of laparoscopic splenectomy on portal haemodynamics in these patients.

Methods

Patients with liver cirrhosis and portal hypertension who underwent laparoscopic splenectomy in Kyushu University Hospital from January 2006 to March 2009 were evaluated retrospectively. Correlations between splenic size and portal haemodynamics, and changes in portal haemodynamics and in levels of the vasoactive agents endothelin (ET) 1 and nitric oxide metabolites (NOx) before and 7–10 days after laparoscopic splenectomy were analysed.

Results

Portal venous (PV) blood flow, PV cross-sectional area and PV congestion index correlated significantly with splenic size (P < 0·050). All three were significantly reduced following splenectomy in 59 patients. The hepatic venous pressure gradient, measured in 18 patients, decreased by 25 per cent after splenectomy (P < 0·001). Portal vascular resistance was also reduced, by 21 per cent (P = 0·009). The peripheral blood concentration of ET-1 decreased from 2·95 to 2·11 pg/ml (P < 0·001), and that of NOx tended to decrease (from 29·2 to 25·0 pg/ml; P = 0·068). In hepatic venous blood, the level of ET-1 decreased from 2·37 to 1·83 pg/ml (P = 0·006), whereas NOx concentration tended to increase (from 24·5 to 30·9 pg/ml; P = 0·067).

Conclusion

In patients with liver cirrhosis and portal hypertension, splenectomy reduced portal venous pressure. A decrease in splanchnic blood flow, by eliminating splenic blood flow, and reduction in intrahepatic vascular resistance, by normalizing hepatic concentrations of ET-1 and NOx, may both have contributed.
Impact of mechanical bowel preparation on survival after colonic cancer resection
Authors: Collin Å , Jung B , Nilsson E , Påhlman L , Folkesson J
Published: September 2014

Background

A randomized study in 1999–2005 of mechanical bowel preparation (MBP) preceding colonic resection found no decrease in postoperative complications. The aim of the present study was to evaluate the long-term effect of MBP regarding cancer recurrence and survival after colonic resections.

Methods

The cohort of patients with colonic cancer in the MBP study was followed up for 10 years. Data were collected from registers run by the National Board of Health and Welfare. Register data were validated against information in patient charts. Cox proportional hazards model was used for multivariable analysis of factors predictive of cancer-specific survival.

Results

Register analysis showed significantly fewer recurrences, and better cancer-specific and overall survival in the MBP group. After validation, 839 of 1343 patients remained for analysis (448 MBP, 391 no MBP). Eighty (17·9 per cent) of 448 patients in the MBP group and 88 (22·5 per cent) of 391 in the no-MBP group developed a cancer recurrence (P = 0·093). The 10-year cancer-specific survival rate was 84·1 per cent in the MBP group and 78·0 per cent in the no-MBP group (P = 0·019). Overall survival rates were 58·8 and 56·0 per cent respectively (P = 0·186).

Conclusion

Patients receiving MBP before elective colonic cancer surgery had significantly better cancer-specific survival after 10 years.
Intramolecular Thioether Crosslinking of Therapeutic Proteins to Increase Proteolytic Stability
Authors: Lindgren Joel , Eriksson Karlström Amelie
Published: September 2014

Protein‐based pharmaceuticals typically display high selectivity and low toxicity, but are also characterized by low oral availability, mainly because of enzymatic degradation in the gastrointestinal tract and poor permeability across the intestinal wall. One way to increase the proteolytic stability of peptides and proteins is by intramolecular crosslinking, such as the introduction of disulfide bridges. However, disulfide bridges are at risk of thiol‐disulfide exchange or reduction during production, purification, and/or therapeutic use, whereas thioether bridges are expected to be stable under the same conditions. In this study, thioether crosslinking was investigated for a 46 aa albumin‐binding domain (ABD) derived from streptococcal protein G. ABD binds with high affinity to human serum albumin (HSA) and has been proposed as a fusion partner to increase the in vivo half‐lives of therapeutic proteins. In the study, five ABD variants with single or double intramolecular thioether bridges were designed and synthesized. The binding affinity, secondary structure, and thermal stability of each protein was investigated by SPR‐based biosensor analysis and CD spectroscopy. The proteolytic stability in the presence of the major intestinal proteases pepsin (found in the stomach) and trypsin in combination with chymotrypsin (found in pancreatin secreted to the duodenum by the pancreas) was also investigated. The most promising crosslinked variant, ABD_CL1, showed high thermal stability, retained high affinity in binding to HSA, and showed dramatically increased stability in the presence of pepsin and trypsin/chymotrypsin, compared to the ABD reference protein. This suggests that the intramolecular thioether crosslinking strategy can be used to increase the stability towards gastrointestinal enzymes.
The Evolutionary Enhancement of Genotype–Phenotype Linkages in the Presence of Multiple Copies of Genetic Material
Authors: Uno Keisuke , Sunami Takeshi , Ichihashi Norikazu , Kazuta Yasuaki , Matsuura Tomoaki , Yomo Tetsuya
Published: September 2014

Genetic evolutionary mechanisms employed by protolife developed without accompanying regulatory mechanisms for the amounts of genetic material in protocells. When many copies of genetic material are present, inactive copies generated by mutations are not effectively excluded through phenotypic selection. We demonstrate a model of gene evolution initiated with different amounts of DNA inside artificial protocells. We adopted transcription‐ and translation‐coupled RNA replication and liposome‐based in vitro compartmentalization. Despite the fact that the average number of DNA copies in each liposome was 6.4, DNA encoding active genes was maintained until the 16th selection round. Our experimental and theoretical results indicated that gene evolution can occur in the presence of multiple DNA copies. Most genetic material became junk code through gene mutations, and consequently the linkage between genotype and phenotype was enhanced through the associated decreases in active genetic material.
A Persulfide Analogue of the Nitrosothiol SNAP: Formation, Characterization and Reactivity
Authors: Artaud Isabelle , Galardon Erwan
Published: September 2014

The proposal of the post‐translational modification “S‐sulfhydration” as a major pathway for H2S‐induced signaling has recently shed light on persulfides. However, the study of these species is hampered by their instability under biologically relevant conditions; this requires generating them in situ immediately prior to use. The current methods to prepare persulfides in aqueous solution suffer from several drawbacks. In particular, their formation requires (or generates) hydrogen sulfide, thus resulting in difficulties in distinguishing polysulfide reactivity from that of H2S. Here we report the H2S‐free formation, characterization, and some biologically relevant reactions of a water‐soluble persulfide analogue of the nitrosothiol SNAP, a widely used nitric oxide donor.
A Site‐Isolated Organoruthenium‐/Organopalladium‐Bifunctionalized Periodic Mesoporous Organosilica Catalyzes Cascade Asymmetric Transfer Hydrogenation and Suzuki Cross‐Coupling
Authors: Zhang Dacheng , Xu Jianyou , Zhao Qiankun , Cheng Tanyu , Liu Guohua
Published: September 2014

An important challenge in asymmetric cascade reactions is solving the intrinsic incompatibility of two types of distinct organometallic complexes that participate in a one‐pot reaction. Herein, we develop an organoruthenium‐/organopalladium‐bifunctionalized periodic mesoporous organosilica and realize one‐pot cascade reactions of Ru‐catalyzed asymmetric transfer hydrogenation and Pd‐relay‐catalyzed cross‐coupling of haloacetophenones and arylboronic acids to various chiral biaryl alcohols, with quantitative conversions and up to 98 % enantioselectivity in an aqueous medium. This characteristics is attributed to the site‐isolated, uniformly distributed, well‐defined single‐site palladium and ruthenium active species. Furthermore, the heterogeneous catalyst is conveniently recovered and reused repeatedly for eight times without loss of its catalytic activity, showing particular attractiveness for practicing organic transformation.
Enriched‐Air Gasification of Refuse‐Derived Fuel in a Fluidized Bed: Effect of Gasifying Conditions and Bed Materials
Authors: Niu Miaomiao , Huang Yaji , Jin Baosheng , Sun Yu , Wang Xinye
Published: September 2014

Enriched‐air gasification of refuse‐derived fuel (RDF) was carried out in a fluidized bed, investigating the effects of temperature, equivalence ratio (ER), oxygen percentage of enriched air (OP), and bed materials. For the bed material effect, calcined dolomite proved to be more effective for tar decomposition and resulted in higher CO and H2 contents. In a bed of high‐alumina bauxite, an increased ER tended to cause a greater decrease in syngas quality. For both bed materials, a higher temperature and OP favored the production of combustible gas and led to higher cold gas efficiency. Increasing the ER resulted in higher gas yields and carbon conversion but lowered the concentration of the combustible component. The ash content of the char increased with temperature and OP, while the volatile and fixed carbon contents were decreased. The optimum conditions suggested in this study were an ER of 0.22 and an OP of 44.7 % at 750–800 °C in a bed of calcined dolomite.
Energy Minimization in Cryogenic Packed Beds during Purification of Natural Gas with High CO2 Content
Authors: Ali Abulhassan , Maqsood Khuram , Syahera Nor , Shariff Azmi B. M. , Ganguly Saibal
Published: September 2014

Minimization of energy consumption was explored for countercurrent switched cryogenic packed beds in which separation of CO2 and other components of natural gas can be achieved based on differences in freezing or desublimation points. Highly pure CO2 and methane were obtained after separation. An experimental setup for CO2 removal from natural gas was constructed and a detailed experimental study was conducted by changing different operating parameters. Compared to other cocurrent or jacket‐cooled constant‐temperature configurations, countercurrent switched beds provided optimal separation and energy efficiencies. The effects of important process parameters like initial temperature profiles of the cryogenic bed, feed composition, and feed flow rate on energy requirement, bed saturation, bed pressure, and cycling times were investigated. The energy requirement for cryogenic packed beds was compared with the conventional cryogenic distillation process.
Chemometric and trend analysis of water quality of the South Chennai lakes: an integrated environmental study
Authors: Loganathan Giridharan , Krishnaraj Suresh , Muthumanickam Jayaprakash , K Ravichandran
Published: September 2014

In order to bring out the nature of the factors influencing lake water composition, multivariate statistical analysis and trend analysis were performed based on the hydrochemical data of the study area, namely, South Chennai. Change in land use pattern and settlements along the banks of the lakes alters the quality and quantity of the surface water. In the present study, the R‐mode factor analysis and cluster analysis were applied to the geochemical parameters of the water to identify the factors affecting the chemical composition of the lake water. Dendograms of both the seasons give three major clusters, reflecting the groups of unpolluted to moderately polluted, polluted, and heavily polluted stations. The movement of stations from one cluster to another clearly brings out the seasonal variation in the chemical composition of the lake water. The complex hydrochemical data of the surface water were interpreted by condensing them into three major factors. Factor score analysis was used successfully to delineate the stations under study and the role of the contributing factors, and the nature of factors responsible for the variation in chemical composition of the water has been clearly brought out. Results of trend analysis using ArcGIS clearly indicate that the trend in water quality is deteriorating at a faster rate in the eastern part of the study area. It is understood that although natural shifts probably can account for some of the variation, it is most likely that human activities play a major role in affecting the water quality on a regional scale. Copyright © 2014 John Wiley & Sons, Ltd.
Modular Molecules: Site‐Selective Metal Substitution, Photoreduction, and Chirality in Polyoxometalate Hybrids
Authors: Vonci Michele , Akhlaghi Bagherjeri Fateme , Hall Peter D. , Gable Robert W. , Zavras Athanasios , O'Hair Richard A. J. , Liu Yuping , Zhang Jie , Field Matthew R. , Taylor Matthew B. , Du Plessis Johan , Bryant Gary , Riley Mark , Sorace Lorenzo , Aparicio Pablo A. , López Xavier , Poblet Josep M. , Ritchie Chris , Boskovic Colette
Published: September 2014

The first members of a promising new family of hybrid amino acid–polyoxometalates have emerged from a search for modular functional molecules. Incorporation of glycine (Gly) or norleucine (Nle) ligands into an yttrium‐tungstoarsenate structural backbone, followed by crystallization with p‐methylbenzylammonium (p‐MeBzNH3+) cations, affords (p‐MeBzNH3)6K2(GlyH)[AsIII4(YIIIWVI3)WVI44YIII4O159(Gly)8‐ (H2O)14]⋅47 H2O (1) and enantiomorphs (p‐MeBzNH3)15(NleH)3 [AsIII4(MoV2MoVI2)WVI44YIII4O160(Nle)9(H2O)11][AsIII4(MoVI2WVI2)‐ WVI44YIII4O160(Nle)9(H2O)11] (generically designated 2: L‐Nle, 2 a; D‐Nle, 2 b). An intensive structural, spectroscopic, electrochemical, magnetochemical and theoretical investigation has allowed the elucidation of site‐selective metal substitution and photoreduction of the tetranuclear core of the hybrid polyanions. In the solid state, markedly different crystal packing is evident for the compounds, which indicates the role of noncovalent interactions involving the amino acid ligands. In solution, mass spectrometric and small‐angle X‐ray scattering studies confirm maintenance of the structure of the polyanions of 2, while circular dichroism demonstrates that the chirality is also maintained. The combination of all of these features in a single modular family emphasizes the potential of such hybrid polyoxometalates to provide nanoscale molecular materials with tunable properties.
New Classes of Ferromagnetic Materials with Exclusively End‐on Azido Bridges: From Single‐Molecule Magnets to 2 D Molecule‐Based Magnets
Authors: Alexandropoulos Dimitris I. , Cunha‐Silva Luís , Escuer Albert , Stamatatos Theocharis C.
Published: September 2014

A new, flexible synthetic route, which does not require the co‐presence of any organic chelating/bridging ligand but only the “key” precursor Me3SiN3, has been discovered and led to a new class of inorganic materials containing exclusively end‐on azido bridges; the reported 3d‐metal clusters and coordination polymers exhibit ferromagnetic, single‐molecule magnet, and long‐range magnetic ordering properties.
Discovery of the Last Remaining Binary Platinum‐Group Pernitride RuN2
Authors: Niwa Ken , Suzuki Kentaro , Muto Shunsuke , Tatsumi Kazuyoshi , Soda Kazuo , Kikegawa Takumi , Hasegawa Masashi
Published: September 2014

The last remaining marcasite‐type RuN2 was successfully synthesized by direct chemical reaction between ruthenium and molecular nitrogen above the pressure of 32 GPa. For the first time, we found that Ru 4d is weakly hybridized with N 2p in the structure by using transmission electron microscopy equipped with electron‐energy‐loss spectroscopy. Our finding give important knowledge about the platinum‐group pernitride with respect to the chemical bonding between platinum‐group element and nitrogen.
Total Synthesis of (R,R,R)‐γ‐Tocopherol through Cu‐Catalyzed Asymmetric 1,2‐Addition
Authors: Wu Zhongtao , Harutyunyan Syuzanna R. , Minnaard Adriaan J.
Published: September 2014

Based on the asymmetric copper‐catalyzed 1,2‐addition of Grignard reagents to ketones, (R,R,R)‐γ‐tocopherol has been synthesized in 36 % yield over 12 steps (longest linear sequence). The chiral center in the chroman ring was constructed with 73 % ee by the 1,2‐addition of a phytol‐derived Grignard reagent to an α‐bromo enone prepared from 2,3‐dimethylquinone.