bluuebunny/crossref_metadata_2025 huggingface dataset:
Two‐Electron Reductive Carbonylation of Terminal Uranium(V) and Uranium(VI) Nitrides to Cyanate by Carbon Monoxide
Authors: Cleaves Peter A. , King David M. , Kefalidis Christos E. , Maron Laurent , Tuna Floriana , McInnes Eric J. L. , McMaster Jonathan , Lewis William , Blake Alexander J. , Liddle Stephen T.
Published: July 2014

Two‐electron reductive carbonylation of the uranium(VI) nitride [U(TrenTIPS)(N)] (2, TrenTIPS=N(CH2CH2NSiiPr3)3) with CO gave the uranium(IV) cyanate [U(TrenTIPS)(NCO)] (3). KC8 reduction of 3 resulted in cyanate dissociation to give [U(TrenTIPS)] (4) and KNCO, or cyanate retention in [U(TrenTIPS)(NCO)][K(B15C5)2] (5, B15C5=benzo‐15‐crown‐5 ether) with B15C5. Complexes 5 and 4 and KNCO were also prepared from CO and the uranium(V) nitride [{U(TrenTIPS)(N)K}2] (6), with or without B15C5, respectively. Complex 5 can be prepared directly from CO and [U(TrenTIPS)(N)][K(B15C5)2] (7). Notably, 7 reacts with CO much faster than 2. This unprecedented f‐block reactivity was modeled theoretically, revealing nucleophilic attack of the π* orbital of CO by the nitride with activation energy barriers of 24.7 and 11.3 kcal mol−1 for uranium(VI) and uranium(V), respectively. A remarkably simple two‐step, two‐electron cycle for the conversion of azide to nitride to cyanate using 4, NaN3 and CO is presented.
[FeFe] Hydrogenase: Protonation of {2Fe3S} Systems and Formation of Super‐reduced Hydride States
Authors: Jablonskytė Aušra , Wright Joseph A. , Fairhurst Shirley A. , Webster Lee R. , Pickett Christopher J.
Published: July 2014

The synthesis and crystallographic characterization of a complex possessing a well‐defined {2Fe3S(μ‐H)} core gives access to a paramagnetic bridging hydride with retention of the core geometry. Chemistry of this 35‐electron species within the confines of a thin‐layer FTIR spectro‐electrochemistry cell provides evidence for a unprecedented super‐reduced FeI(μ‐H)FeI intermediate.
Induction of Interleukin‐6 Production by Rituximab in Human B Cells
Authors: Jones Jonathan D. , Hamilton B. JoNell , Skopelja Sladjana , Rigby William F. C.
Published: July 2014

Objective

Rituximab (RTX), an anti‐CD20 monoclonal antibody, is highly effective in the treatment of several autoimmune diseases. The mechanism by which RTX treatment improves rheumatoid arthritis and antineutrophil cytoplasmic antibody–associated vasculitis is not easily related to B cell depletion alone. Prior studies have shown that RTX mediates a rapid stripping of CD20 and CD19 from the human B cell through a process known as trogocytosis. The aim of the present study was to investigate whether changes in B cell phenotype resulting from trogocytosis would diminish the ability of B cells to promote autoimmune disease.

Methods

Human peripheral blood mononuclear cells were cultured with RTX under conditions that permitted trogocytosis. Changes in B cell phenotype and cytokine production were measured in the basal state and under conditions of activation with interleukin‐4 (IL‐4)/anti‐CD40. The effects of RTX were characterized in terms of a requirement for interaction with the Fcγ receptor (FcγR) and other Fc‐dependent interactions.

Results

Trogocytosis induced a marked loss of surface CD19, IgD, CD40, and B cell–activating factor receptor, but did not alter induction of CD86 expression on purified B cells following IL‐4/anti‐CD40 treatment. Unexpectedly, RTX‐dependent trogocytosis of normal human B cells in vitro led to a rapid up‐regulation of IL‐6 production, with no effect on the production of tumor necrosis factor α, IL‐1β, interferon‐γ, or IL‐10. This effect was Fc‐dependent and required the presence of an FcγR‐bearing cell. Moreover, this effect involved the release of preformed intracellular IL‐6 protein, as well as marked increases in IL‐6 messenger RNA levels.

Conclusion

RTX‐mediated trogocytosis of B cells in vitro results in acute production and release of IL‐6. The nature of this effect and how it is related to the acute infusion reactions seen with RTX administration remain to be determined.
Clinical Features, Treatment, and Outcome of Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis: A Multinational, Multicenter Study of 362 Patients
Authors: Minoia Francesca , Davì Sergio , Horne AnnaCarin , Demirkaya Erkan , Bovis Francesca , Li Caifeng , Lehmberg Kai , Weitzman Sheila , Insalaco Antonella , Wouters Carine , Shenoi Susan , Espada Graciela , Ozen Seza , Anton Jordi , Khubchandani Raju , Russo Ricardo , Pal Priyankar , Kasapcopur Ozgur , Miettunen Paivi , Maritsi Despoina , Merino Rosa , Shakoory Bita , Alessio Maria , Chasnyk Vyacheslav , Sanner Helga , Gao Yi‐Jin , Huasong Zeng , Kitoh Toshiyuki , Avcin Tadej , Fischbach Michel , Frosch Michael , Grom Alexei , Huber Adam , Jelusic Marija , Sawhney Sujata , Uziel Yosef , Ruperto Nicolino , Martini Alberto , Cron Randy Q. , Ravelli Angelo ,   on behalf of the Pediatric Rheumatology International Trials Organization, the Childhood Arthritis and Rheumatology Research Alliance, the Pediatric Rheumatology Collaborative Study Group, and the Histiocyte Society
Published: July 2014

Objective

To describe the clinical, laboratory, and histopathologic features, current treatment, and outcome of patients with macrophage activation syndrome (MAS) complicating systemic juvenile idiopathic arthritis (JIA).

Methods

In this multinational, multicenter study, pediatric rheumatologists and hemato‐oncologists entered patient data collected retrospectively into a web‐based database.

Results

A total of 362 patients, 22% of whom had MAS at the onset of systemic JIA, were included in the study by 95 investigators from 33 countries. The most frequent clinical manifestations were fever (96%), hepatomegaly (70%), and splenomegaly (58%). Central nervous system dysfunction and hemorrhages were recorded in 35% and 20% of the patients, respectively. Platelet count and liver transaminase, ferritin, lactate dehydrogenase, triglyceride, and d‐dimer levels were the sole laboratory biomarkers showing a percentage change of >50% between the pre‐MAS visit and MAS onset. Evidence of macrophage hemophagocytosis was found in 60% of the patients who underwent bone marrow aspiration. MAS occurred most frequently in the setting of active underlying disease, in the absence of a specific trigger. Nearly all patients were given corticosteroids, and 61% received cyclosporine. Biologic medications and etoposide were given to 15% and 12% of the patients, respectively. Approximately one‐third of the patients required admission to the intensive care unit (ICU), and the mortality rate was 8%.

Conclusion

This study provides information on the clinical spectrum and current management of systemic JIA–associated MAS through the analysis of a very large patient sample. MAS remains a serious condition, as a sizeable proportion of patients required admission to the ICU or died.
Robust H∞ Output Tracking Control with Partly Quantized Information
Authors: Ge Yang , Wang Jingcheng , Zhang Langwen , Li Chuang
Published: July 2014

This paper is concerned with the stability and output tracking problems of networked control systems (NCSs) with partly quantized information. Both the remote and local systems are considered. The state variables transported from the remote system experiences time delays and quantization errors, while the local state variables do not. The purpose is to design a state feedback controller which guarantees that the output of the local system tracks the output of the remote system in the H∞ sense. This consideration is widely appeared in remote assistant systems. Based on the Lyapunov–Krasovskii (L‐K) functional approach, sufficient conditions on the existence of a quantized robust H∞ output tracking controller for NCSs are presented in terms of bilinear matrix inequalities (BMIs). Furthermore, a cone complementarity algorithm is used to convert these BMIs into a convex optimization problem. Finally, a simulation example is given to demonstrate the efficiency of the proposed method.
Identification and Compensation of Force Ripple in PMSLM using a JITL Technique
Authors: Lu Shaowu , Tang Xiaoqi , Song Bao , Zheng Shiqi , Zhou FengXing
Published: July 2014

This paper presents an adaptive compensation scheme for reducing the force ripple effects in permanent magnet synchronous linear motor (PMSLM). Firstly, when the velocity of a linear motor is close to zero, based on a fast Fourier transform (FFT) analysis, the dominant displacement periodicity of the force ripple can be obtained for simplifying the ripple model. Next, to enhance the identification accuracy and guarantee the real‐time performance of the linear servo system simultaneously, an improved just‐in‐time learning (JITL) algorithm is proposed to estimate the ripple model parameters. Finally, based on the identification results, an adaptive feedforward controller is implemented in the linear servo system to compensate the force ripple. The main motivation of this paper is the extension of the identification methods to improve the servo control performance in industrial applications. Simulation and experimental results demonstrate the effectiveness of the proposed method, even when compared to a traditional compensation method based on a recursive least squares algorithm.
Pregnancy outcome in women assigned an ICD‐9/ICD‐9‐CM 655.0 code “central nervous system malformation in fetus affecting management of pregnancy”: Can these codes aid in surveillance for central nervous system defects?
Authors: Evans Jane A
Published: July 2014

Background

The difficulty many birth defects registries have in identifying early pregnancy terminations can lead to significant underreporting of certain types of malformations. This study was designed to determine the potential benefit of using maternal ICD‐9 codes relating to management of pregnancy due to fetal anomaly in surveillance of central nervous system (CNS) defects (655.0).

Methods

Women assigned the ICD‐9/ICD‐9‐CM (henceforth termed ICD‐9) code 655.0 between 1990 and 2000 were ascertained from two administrative health databases in Manitoba, Canada, one relating to maternal serum screening and one based on hospital discharges. Information was collected on the type of CNS defect identified and whether it was isolated or associated with other anomalies. The relationship of these variables to pregnancy outcome and its potential impact on surveillance for these types of defects was explored.

Results

Neural tube defects were the most common finding (67%) identified in the fetuses/infants of women assigned code 655.0, followed by hydrocephaly (20%) and Dandy‐Walker anomaly (6%), but the proportion of neural tube defect cases declined after food fortification with folic acid. Termination of pregnancy occurred in ∼50% of neural tube defect cases, 18% before 20 weeks of gestation, but was rare for other CNS defects.

Conclusion

The maternal ICD‐9 code 655.0 had a very high (97%) positive predictive value for identifying fetuses with a CNS defect; 655.00 was particularly effective in identifying neural tube defects pregnancies terminated before 20 weeks gestation that would be difficult to ascertain, especially by passive surveillance systems using infant related data alone. Birth Defects Research (Part A) 100:848–851, 2014. © 2014 Wiley Periodicals, Inc.
Hydranencephaly in a newborn with a FLVCR2 mutation and prenatal exposure to cocaine
Authors: Soster Erica L. , Tucker Megan , Escobar Luis F. , Vance Gail H.
Published: July 2014

Background

Hydranencephaly is a relatively rare but severe structural brain abnormality that often results in perinatal death. Although several factors including infection and multiple births have been reported to be associated with this birth defect, the underlying etiology is not well understood. Recently, FLVCR2 gene mutations have been implicated in a subset of hydranencephaly cases, following an autosomal recessive pattern of inheritance.

Case

We report a male infant with hydranencephaly found to have a previously unreported six amino acid deletion in one copy of the FLVCR2 gene following a pregnancy complicated by poor prenatal care and maternal cocaine use. Although our patient currently presents with developmental delays, he is showing progress and gaining some skills.

Conclusion

We discuss the possibility of a synergistic effect between the FLVCR2 genetic mutation and environmental cocaine exposure, creating a susceptible brain, as an explanation for this infant's phenotype. This case demonstrates the potential clinical utility of testing for mutations in FLVCR2 for patients with hydranencephaly after other possible etiologies, such as congenital infection, have been reasonably eliminated. Current literature on FLVCR2 is relatively sparse; identifying additional patients with similar mutations will aid in defining the clinical significance of a gene mutation and the contribution to the etiology of hydranencephaly. Birth Defects Research (Part A) 103:45–50, 2015. © 2014 Wiley Periodicals, Inc.
Understanding and modeling alternating tangential flow filtration for perfusion cell culture
Authors: Kelly William , Scully Jennifer , Zhang Di , Feng Gang , Lavengood Mathew , Condon Jason , Knighton John , Bhatia Ravinder
Published: July 2014

Alternating tangential flow (ATF) filtration has been used with success in the Biopharmaceutical industry as a lower shear technology for cell retention with perfusion cultures. The ATF system is different than tangential flow filtration; however, in that reverse flow is used once per cycle as a means to minimize fouling. Few studies have been reported in the literature that evaluates ATF and how key system variables affect the rate at which ATF filters foul. In this study, an experimental setup was devised that allowed for determination of the time it took for fouling to occur for given mammalian (PER.C6) cell culture cell densities and viabilities as permeate flow rate and antifoam concentration was varied. The experimental results indicate, in accordance with D'Arcy's law, that the average resistance to permeate flow (across a cycle of operation) increases as biological material deposits on the membrane. Scanning electron microscope images of the post‐run filtration surface indicated that both cells and antifoam micelles deposit on the membrane. A unique mathematical model, based on the assumption that fouling was due to pore blockage from the cells and micelles in combination, was devised that allowed for estimation of sticking factors for the cells and the micelles on the membrane. This model was then used to accurately predict the increase in transmembane pressure during constant flux operation for an ATF cartridge used for perfusion cell culture. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1291–1300, 2014
Nanotubular structures developed from whey‐based α‐lactalbumin fractions for food applications
Authors: Tarhan Özgür , Harsa Şebnem
Published: July 2014

Whey proteins have high nutritional value providing use in dietary purposes and improvement of technological properties in processed foods. Functionality of the whey‐based α‐lactalbumin (α‐La) may be increased when assembled in the form of nanotubes, promising novel potential applications subject to investigation. The purpose of this study was to extract highly pure α‐La from whey protein isolate (WPI) and whey powder (WP) and to construct protein nanotubes from them for industrial applications. For protein fractionation, WPI was directly fed to chromatography, however, WP was first subjected to membrane filtration and the retentate fraction, whey protein concentrate (WPC), was obtained and then used for chromatographic separation. α‐La and, additionally β‐Lg, were purified at the same batches with the purities in the range of 95%–99%. After enzymatic hydrolysis, WPI‐based α‐La produced chain‐like and long nanotubules with ∼20 nm width while WPC‐based α‐La produced thinner, miscellaneous, and fibril‐like nanostructures by self‐assembly. Raman and FT‐IR spectroscopies revealed that α‐La fractions, obtained from both sources and the nanostructures, developed using both fractions have some structural differences due to conformation of secondary structure elements. Nanotube formation induced gelation and nanotubular gel network entrapped a colorant uniformly with a transparent appearance. Dairy‐based α‐La protein nanotubules could be served as alternative gelling agents and the carriers of natural colorants in various food processes. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1301–1310, 2014
Svelte integrated delivery system performance examined through diagnostic catheter delivery: The SPEED registry
Authors: Khattab Ahmed A. , Nijhoff Freek , Schofer Joachim , Berland Jacques , Meier Bernhard , Nietlispach Fabian , Agostoni Pierfrancesco , Brucks Steffen , Stella Pieter
Published: July 2014

Aims

The multi‐center SPEED registry evaluated the procedural success and in‐hospital clinical outcomes of direct stenting with the Svelte ‘all‐in‐one’ coronary stent Integrated Delivery System (IDS) through diagnostic catheters to identify the clinical indications for which this approach is appropriately suited.

Methods & results

Forty‐eight (48) patients with 54 lesions of lengths ≤20 mm and RVD 2.5–3.5 mm were targeted for direct stenting through diagnostic catheters (4–6F) via radial or femoral approach. Procedural characteristics early in an investigator's experience (28 lesions) were compared with outcomes following experience (26 lesions). Procedure, device and strategy success were realized in 54 (100%), 50 (93%) and 46 (85%) lesions, respectively, with strategy success significantly related to RVD (P = 0.05), lesion location (P = 0.01), and diagnostic catheter size (P = 0.05). Significant improvement in crossing and intervention time and trends toward improvement in device and strategy success, reductions in procedure and radiation time and contrast use were observed.

Conclusions

Direct stenting through diagnostic catheters via radial or femoral approach using the Svelte IDS is feasible and associated with good in‐hospital outcomes. This approach offers the attractive option of assessing lesions via diagnostic catheter and, depending upon vessel anatomy and lesion morphology, continuing with ad‐hoc interventional treatment using the same diagnostic catheter. Improvements in strategy success and procedural efficiencies, based on operator experience, facilitate catheter downsizing and reduce intervention time, ancillary product use and overall procedure costs. © 2014 Wiley Periodicals, Inc.
Dysautonomic responses during percutaneous carotid intervention
Authors: Bujak Marcin , Stilp Erik , Meller Stephanie M. , Cal Nicolas , Litsky Jason , Setaro John F. , Mena Carlos
Published: July 2014

Percutaneous carotid artery stenting (CAS) has emerged as a less invasive alternative to carotid endarterectomy for the treatment of carotid atherosclerotic disease. The main risk of CAS is the occurrence of neuro‐vascular complications; however, carotid artery stenting‐related dysautonomia (CAS‐D) (hypertension, hypotension, and bradycardia) is the most frequently reported problem occurring in the periprocedural period. Alterations in autonomic homeostasis result from baroreceptor stimulation, which occurs particularly at the time of balloon inflation in the region of the carotid sinus. The response can be profound enough to induce asystole or even complete cessation of postganglionic sympathetic nerve activity. Frequency and factors predisposing a patient to CAS‐D have been investigated in several studies; however, there are significant discrepancies in results among reports. Lack of consistent findings may arise from using different methods and definitions, as well as other factors discussed in detail in this review. Furthermore, a correlation of CAS‐D with short and long‐term outcomes has been investigated only in small and mostly retrospective studies, explaining why its prognostic significance remains uncertain. In this manuscript, we have focused on risk factors, pathophysiology and management of periprocedural autonomic dysfunction. As there is no standardized approach to the treatment of CAS‐D, we present an algorithm for the periprocedural management of patients undergoing CAS. The proposed algorithm was developed based on our procedural experience as well as data from the available literature. The Yale Algorithm was successfully implemented at our institution and we are currently collecting data for short‐ and long‐term safety. © 2014 Wiley Periodicals, Inc.
Iatrogenic right coronary artery stenosis resulting from surgical tricuspid valve replacement
Authors: Morrissy Stephen J. , Atkins Broadus Zane , Rogers Jason H.
Published: July 2014

Iatrogenic injury to the right coronary artery (RCA) is a rare complication of tricuspid valve surgery. We herein describe the first‐ever report of RCA injury related to tricuspid valve replacement surgery. A 38‐year‐old man with recurrent tricuspid endocarditis underwent redo tricuspid valve replacement by means of a minimally invasive right thoracotomy with a 32‐mm St. Jude bioprosthetic valve. His post‐operative course was complicated by pulseless ventricular tachycardia requiring CPR and defibrillation. Cardiac catheterization revealed a “kinked” stenotic distal RCA. The lesion was noted to be flow limiting by fractional flow reserve and was treated with two everolimus‐eluting stents. The RCA runs in the atrioventricular groove and is susceptible to injury especially in the region of the posterior leaflet of the tricuspid valve, where the relationship of the tricuspid annulus to the RCA is most intimate. Repair of surgically induced coronary stenosis can be accomplished with percutaneous intervention. © 2014 Wiley Periodicals, Inc.
Copper in Photocatalysis
Authors: Paria Suva , Reiser Oliver
Published: July 2014

Light‐induced electron transfer (CuI to CuII), oxidative addition (CuI to CuIII), or the activation of copper alkene or alkyne complexes are possible key steps that offer unique possibilities for organic synthesis, including [2+2]‐cycloadditions, cross‐coupling reactions or atom transfer radical additions. This Minireview provides an overview on the photophysical properties of photocatalysts based on copper and on synthetic transformations mediated by them.
Bubble Volume and Aspect Ratio Generated in Non‐Newtonian Fluids
Authors: Fan Wenyuan , Sun Yawei , Chen Hui
Published: July 2014

Bubble formation from an orifice submerged in quiescent polyacrylamide aqueous solution was investigated numerically with a sharp‐interface coupled level‐set/volume‐of‐fluid method based on the rheological characteristics of the fluid. In both non‐Newtonian fluids and Newtonian fluids, the numerical approach was able to capture accurately the deformation of the bubble surface, validated by comparison with experimental results. The effects of orifice diameter, solution mass concentration, and gas flow rate on bubble volume and aspect ratio were evaluated. Both the instantaneous and detached volume decrease with the orifice diameter but increase with mass concentration and gas flow rate. The aspect ratio at the departing point tends to rise with the orifice diameter and mass concentration and falls with the gas flow rate.
A mathematical model of measurement uncertainty of single substrate enzyme assays
Authors: Ramamohan Varun , Abbott James T. , Yih Yuehwern
Published: July 2014

Clinical laboratory tests provide critical information at every stage of the medical decision‐making process, and measurement of the activity levels of enzymes such as alkaline phosphatase, lactate dehydrogenase, etc. provide information regarding various body functions such as the liver and gastrointestinal tract. The uncertainty associated with these enzyme measurement processes describes the quality of the measurement process, and therefore methods to improve the quality of the measurement process require minimizing the measurement uncertainty of the enzyme assay. In this study, we develop a mathematical model of the lactate dehydrogenase measurement process, with uncertainty introduced into its parameters that represent the sources of variation in the different components and stages of the measurement process. The Monte Carlo method is then utilized to estimate the uncertainty associated with the model, and therefore the measurement process. An empirical function used to generate estimates of uncertainty for patient samples with unknown activity levels is constructed using the model. The model is then used to quantify the contributions of the individual sources of uncertainty to the net measurement uncertainty and also quantify the effect of uncertainty within the calibration process on the distribution of the measurement result. Copyright © 2014 John Wiley & Sons, Ltd.
High Resolution Scanning Tunneling Microscopy of a 1D Coordination Polymer with Imidazole‐Based N,N,O Ligands on HOPG
Authors: Fischer Nina V. , Mitra Utpal , Warnick Karl‐Georg , Dremov Viacheslav , Stocker Michael , Wölfle Thorsten , Hieringer Wolfgang , Heinemann Frank W. , Burzlaff Nicolai , Görling Andreas , Müller Paul
Published: July 2014

Novel κ3‐N,N,O ligands tend to form 1D coordination polymer strands. Deposition of 1D structures on highly oriented pyrolytic graphite (HOPG) was achieved from diluted solutions and polymer strands have been studied on HOPG by AFM/STM. Single strands were mapped by STM and their electronic properties were subsequently characterized by current imaging tunneling spectroscopy (CITS). Periodic density functional calculations simulating a polymer strand deposited on a HOPG surface are in agreement with the zig‐zag structure indicated by experimental findings. Both the observed periodicity and the Zn–Zn distances can be reproduced in the simulations. Van der Waals interactions were found to play a major role for the geometry of the isolated polymer strand, for the adsorption geometry on HOPG, as well as for the adsorption energy.
Multistep Flow Synthesis of 5‐Amino‐2‐aryl‐2H‐[1,2,3]‐triazole‐4‐carbonitriles
Authors: Jacq Jérôme , Pasau Patrick
Published: July 2014

1,2,3‐Triazole has become one of the most important heterocycles in contemporary medicinal chemistry. The development of the copper‐catalyzed Huisgen cycloaddition has allowed the efficient synthesis of 1‐substituted 1,2,3‐triazoles. However, only a few methods are available for the selective preparation of 2‐substituted 1,2,3‐triazole isomers. In this context, we decided to develop an efficient flow synthesis for the preparation of various 2‐aryl‐1,2,3‐triazoles. Our strategy involves a three‐step synthesis under continuous‐flow conditions that starts from the diazotization of anilines and subsequent reaction with malononitrile, followed by nucleophilic addition of amines, and finally employs a catalytic copper(II) cyclization. Potential safety hazards associated with the formation of reactive diazonium species have been addressed by inline quenching. The use of flow equipment allows reliable scale up processes with precise control of the reaction conditions. Synthesis of 2‐substituted 1,2,3‐triazoles has been achieved in good yields with excellent selectivities, thus providing a wide range of 1,2,3‐triazoles.
Benzimidazole Derivatives: Synthesis, Physical Properties, and n‐Type Semiconducting Properties
Authors: Mamada Masashi , Pérez‐Bolívar César , Kumaki Daisuke , Esipenko Nina A. , Tokito Shizuo , Anzenbacher Pavel
Published: July 2014

A series of new benzimidazole derivatives were synthesized by the solid‐state condensation and direct sublimation (SSC‐DS) method and their physical properties were investigated. The reaction yields and product stability were significantly affected by the identity of the diamine and anhydride substituents. On the other hand, the substituents of the benzimidazole ring allowed fine tuning of the emission maxima, fluorescence quantum yields, and redox potentials. The HOMO–LUMO levels were estimated by cyclic voltammetry in film on indium tin oxide (ITO) and compared with values obtained by other methods. The described benzimidazoles showed high crystallinity, which is attributed to a high planarity and interactions between carbon and heteroatoms. These compounds showed n‐type semiconducting behavior in organic field‐effect transistors (OFETs). Optimized devices for fluorinated NTCBI (naphthalene tetracarboxylic bisbenzimidazole) showed respectable electron mobilities of ∼10−2 cm2 V−1 s−1.
Gold(I)‐Catalyzed Furan‐yne Cyclizations Involving 1,2‐Rearrangement: Efficient Synthesis of Functionalized 1‐Naphthols and Its Application to the Synthesis of Wailupemycin G
Authors: Chen Yifeng , Wang Lu , Sun Ning , Xie Xin , Zhou Xiaobo , Chen Haoyi , Li Yuxue , Liu Yuanhong
Published: July 2014

Gold‐catalyzed cascade cyclization/1,2‐rearrangement of 1‐(2‐furanyl)phenyl propargyl alcohols has been developed, which provides a rapid and efficient access to multisubstituted 1‐naphthols bearing an enal or enone moiety with high stereoselectivity. The (Z)‐ or (E)‐stereochemistry can be easily controlled by choosing protected‐ or non‐protected substrates. The utility of the methodology has been illustrated in the first total synthesis of wailupemycin G.
Phosphaketenes as Building Blocks for the Synthesis of Triphospha Heterocycles
Authors: Heift Dominikus , Benkő Zoltán , Grützmacher Hansjörg
Published: July 2014

Unsaturated phosphorus compounds, such as phosphaalkenes and phosphaalkynes, show a versatile reactivity in cycloadditions. Although phosphaketenes (RPCO) have been known for three decades, their chemistry has remained limited. Herein, we show that heteroatom‐substituted phosphaketenes, R3EPCO (E=Si, Sn), are building blocks for silyl‐ and stannyl‐substituted five‐membered heterocycles containing three phosphorous atoms. The structure of the heterocyclic anion depends on the nature of the tetrel atom involved. Although the silyl analogue [P3C2(OSiR3)2]− is an aromatic 1,2,4‐triphospholide, the stannyl compound [P(CO)2(PSnR3)2]− is a 1,2,4‐triphosphacyclopenta‐3,5‐dionate with a delocalized OCPCO fragment. Because of their anionic character, these compounds can easily be used as building blocks, for example, in the preparation of a silyl‐functionalized hexaphosphaferrocene or the parent 1,2,4‐triphosphacyclopenta‐3,5‐dionate [P(CO)2(PH)2]−. NMR spectroscopic investigations and computations have shown that the heterocycle‐formation reactions presented herein are remarkably complex.
Multifunctional Inorganic Nanocontainers for DNA and Drug Delivery into Living Cells
Authors: Lülf Henning , Bertucci Alessandro , Septiadi Dedy , Corradini Roberto , De Cola Luisa
Published: July 2014

Invited for the cover of this issue is the group of Luisa De Cola at the University of Strasbourg, ISIS, (France) and her collaborator, Roberto Corradini from Università degli Studi di Parma (Italy). Their study demonstrates the use of multifunctional zeolite L nanoparticles for the simultaneous delivery of foreign DNA and organic molecules into living cells. The fate and the kinetics of the different labeled components have been followed by confocal microscopy. Read the full text of the article at 10.1002/chem.201403232.
Micropetrographic Classification of Solid Residues from Lignite Upgrading with the Reflected Light Microscope
Authors: Hamann Henny , Volkmann Norbert , Vogt Kristin , Burkhardt Saskia
Published: July 2014

Für die Kohleveredlung mittels Pyrolyse bzw. Hydrierung ist eine Vorhersage des komplexen Prozessverhaltens einer Kohle von besonderer Bedeutung. Einen Ansatz hierfür bildet die systematische mikropetrographische Untersuchung der festen Prozessrückstände. Dabei wurde eine dreigeteilte Klassifikation erstellt, welche die Residualkomponenten in originäre Kohlenmacerale, verkokte Anteile und den anorganischen Rückstand gliedert. Neben einer allgemeingültigen Nomenklatur werden die Komponenten als Indikatoren für den Prozessablauf angesehen und mögliche Hinweise zur Prozessoptimierung gegeben.
Experimental Investigation of Primary Fragmentation of Coal Particles in a Drop‐DSC
Authors: Friedemann Jan , Baitalow Felix , Ceia Tiago F. , Rußig Sascha , Meyer Bernd
Published: July 2014

In der vorliegenden Arbeit wurde das Partikelzerfallsverhalten von 18 Kohlen unter Hochtemperaturbedingungen in einem Drop‐Kalorimeter untersucht. Dabei zeigt sich, dass das Fragmentierungsverhalten stark von der eingesetzten Kohle abhängt, aber tendenziell mit zunehmendem Inkohlungsgrad ansteigt. Weiterhin wurde festgestellt, dass der Fragmentierungsfaktor mit steigender Temperatur und Partikelgröße stark zunimmt. Voraussetzung dafür ist jedoch, dass ein kritischer Wert der Temperatur und der Partikelgröße überschritten wird.
Experimental investigation of simultaneous water and CO2 (SWACO2) injection for oil recovery in immiscible and near‐miscible conditions: A comparative study
Authors: Seyyedsar Seyyed Mehdi , Ghazanfari Mohammad Hossein , Taghikhani Vahid
Published: July 2014

A simultaneous water and CO2 injection to a dead crude oil has been performed on sandstone cores to evaluate oil recovery under secondary immiscible, secondary near‐miscible, tertiary immiscible, and tertiary near‐miscible injection modes. It is demonstrated that secondary SWACO2 injection as well as tertiary flood is an effective method for oil/residual oil recovery from oil‐saturated/water flooded porous media. In near‐miscible condition, oil recovery is higher than in immiscible condition because there is another active pore‐scale production mechanism in near‐miscible injection besides volumetric displacement mechanism. In secondary near‐miscible SWACO2 injection, the ultimate oil recovery increases by increasing SWAG ratio from 0.2 to 0.4 but due to some limits, e.g., topological effects, prohibiting contact of injected gas with residual oil in pores, altering SWAG ratio from 0.4 to 0.6 showed no essential effect on ultimate oil recovery. Secondary SWACO2 injection can recover higher fraction of oil than tertiary SWACO2 injection. This higher oil recovery results from the oil being more accessible by injected gas due to less water‐shielding effects. The results of this work can be helpful to better recognition and selection of gas‐based oil recovery methods to be implemented in depleted reservoirs.
Precise Recovery of the Earth's Gravitational Field by Grace Follow‐On Satellite Gravity Gradiometry Method
Authors: Wei ZHENG , Hou‐Tse HSU , Min ZHONG , Mei‐Juan YUN
Published: July 2014

Because the twin GRACE Follow‐On satellites are equivalent to the one‐dimensional horizontal gravity gradiometer with a baseline length of the intersatellite range, the feasibility demonstrations on precisely and rapidly recovering the next‐generation Earth's gravitational field by the GRACE Follow‐On satellite gravity gradiometry method (GFO‐SGGM) are carried out in this study. The research results are as follows: Firstly, based on the GRACE Follow‐On satellite gravity gradiometry method, using the orbital parameters of the satellite (e.g. orbital altitude of 250 km, intersatellite range of 50 km, orbital inclination of 89° and orbital eccentricity of 0.001), the measurement precisions of key payloads (e.g. 10−6 m in intersatellite range, 10−7 m·s−1 in intersatellite range‐ rate and 10−10 m·s−2 in intersatellite range‐acceleration by the interferometric laser ranging system, 10−3 m in orbital position and 10−6 m·s−1 in orbital velocity by the GPS receiver, and 10−11 m·s−2 in non‐conservative force by the accelerometer), a 30‐day observation time and a sampling interval of 10 s, the Earth's gravitational field complete up to degree and order 120 is accurately recovered, and the cumulative geoid height error is 9.331×10−4 m at degree 120. Secondly, in 120 degrees, the accuracy of the gravity recovery from the future twin GRACE Follow‐On satellites is averagely improved by about 61 times than that from the current twin GRACE satellites. Therefore, the GRACE Follow‐On satellite gravity gradiometry method promisingly becomes a preferred approach for further improving the determination accuracy of the next‐generation Earth gravity field model. Finally, the advantages of the next‐generation GRACE Follow‐On mission as compared with the present GRACE mission principally consist of the lower orbital altitude of the satellite between 200 km and 300 km, the higher measurement accuracy of the space‐borne instruments between 10−7 m·s−1 and 10−9 m·s−1 and the shorter intersatellite range between 50 km and 100 km.
Effect of Deposition Rate on Geothermal Field in the Bozhong Depression, Bohai Bay Basin
Authors: Wen‐Zheng LI , Ya‐Xian JIAO , Yin‐Hui ZUO , Xin‐Ying SONG , Nan‐Sheng QIU
Published: July 2014

Thermal anomalies can be caused by fast and intensive tectonism in sedimentary basins. So such thermal anomalies should be eliminated when the thermal history is used to reveal the geodynamic process at depth. In this work, based on the dynamic‐instantaneous heat conduction theory, geothermal correction of 3 typical wells in the Bozhong Depression was carried out. The results indicate that the Paleogene rapid subsidence in the Bozhong depression leads to the present geothermal disequilibrium, where average heat flow at present is about 60.9 mW·m−2, but a higher heat flow 67.4 mW·m−2 is yielded after correction of the low thermal anomalies. The average thermal lithosphere thickness in the Bozhong depression is about 70 km, calculated by using the corrected heat flow, which is 13∼28 km thinner than before correction (82∼100 km), consistent with that from geophysical and xenoliths analyses.
Are 1,4‐ and 1,5‐Disubstituted 1,2,3‐Triazoles Good Pharmacophoric Groups?
Authors: Massarotti Alberto , Aprile Silvio , Mercalli Valentina , Del Grosso Erika , Grosa Giorgio , Sorba Giovanni , Tron Gian Cesare
Published: July 2014

Over the last decade, 1,2,3‐triazoles have received increasing attention in medicinal chemistry thanks to the discovery of the highly useful and widely applicable 1,3‐dipolar cycloaddition reaction between azides and alkynes (click chemistry) catalyzed by copper salts and ruthenium complexes. After a decade of medicinal chemistry research on 1,2,3‐triazoles, we feel that the time is ripe to demonstrate the real ability of this heterocycle to participate in important and pivotal binding interactions with biological targets while maintaining a good pharmacokinetic profile. In this study, we retrieved and analyzed X‐ray crystal structures of complexes between 1,2,3‐triazoles and either proteins or DNA to understand the pharmacophoric role of the triazole. Furthermore, the metabolic stability, the capacity to inhibit cytochromes, and the contribution of 1,2,3‐triazoles to the overall aqueous solubility of compounds containing them have been analyzed. This information should furnish fresh insight for medicinal chemists in the design of novel bioactive molecules that contain the triazole nucleus.
Double GC:GC Mismatch in dsDNA Enhances Local Dynamics Retaining the DNA Footprint: A High‐Resolution NMR Study
Authors: Ghosh Anirban , Kar Rajiv Kumar , Krishnamoorthy Janarthanan , Chatterjee Subhrangsu , Bhunia Anirban
Published: July 2014

Mutations in the genome are responsible for several fatal genetic disorders. The default DNA repair mechanism restores the malfunction of the gene caused by mutation to maintain functional regularity and sequential integrity of the cell. Here, we have elucidated the NMR structure and the dynamics of GC mismatched DNA (PDB code: 2MJX) and found that the mismatched DNA still retains the typical B‐type helical form, but in the process introduces backbone distortion resulting from frame‐shifted base pairs.
Determination of liver‐specific r2* of a highly monodisperse USPIO by 59Fe iron core‐labeling in mice at 3 T MRI
Authors: Raabe Nina , Forberich Evelyn , Freund Barbara , Bruns Oliver T. , Heine Markus , Kaul Michael G. , Tromsdorf Ulrich , Herich Lena , Nielsen Peter , Reimer Rudolph , Hohenberg Heinrich , Weller Horst , Schumacher U. , Adam Gerhard , Ittrich Harald
Published: July 2014

Accurate determination of tissue concentration of ultrasmall superparamagnetic iron oxide nanoparticles (USPIO) using T2* MR relaxometry is still challenging. We present a reliable quantification method for local USPIO amount with the estimation of the liver specific relaxivity r2* using monodisperse 59Fe‐core‐labeled USPIO (59FeUSPIO). Dynamic and relaxometric in vivo characteristics of unlabeled monodisperse USPIO were determined in MRI at 3 T. The in vivo MR studies were performed for liver tissue with 59FeUSPIO using iron dosages of 9 (n = 3), 18 (n = 2) and 27 (n = 3) µmol Fe kg−1 body weight. The R2* of the liver before and after USPIO injection (∆R2*) was measured and correlated with 59Fe activity measurements of excised organs by a whole body radioactivity counter (HAMCO) to define the dependency of ∆R2* and 59FeUSPIO liver concentration and calculate the r2* of 59FeUSPIO for the liver. Ultrastructural analysis of liver uptake was performed by histology and transmission electron microscopy. ∆R2* of the liver revealed a dosage‐dependent accumulation of 59FeUSPIO with a percentage uptake of 70–88% of the injection dose. Hepatic ∆R2* showed a dose‐dependent linear correlation to 59FeUSPIO activity measurements (r = 0.92) and an r2* in the liver of 481 ± 74.9 mm−1 s−1 in comparison to an in vitro r2* of 60.5 ± 3.3 mm−1 s−1. Our results indicate that core‐labeled 59FeUSPIO can be used to quantify the local amount of USPIO and to estimate the liver‐specific relaxivity r2*. Copyright © 2014 John Wiley & Sons, Ltd.
Non‐clairvoyant reduction algorithms for heterogeneous platforms
Authors: Benoit A. , Canon L.‐C. , Marchal L.
Published: July 2014

We revisit the classical problem of the reduction collective operation in a heterogeneous environment. We discuss and evaluate four algorithms that are non‐clairvoyant, that is, they do not know in advance the computation and communication costs. On the one hand, Binomial‐stat and Fibonacci‐stat are static algorithms that decide in advance which operations will be reduced, without adapting to the environment; they were originally defined for homogeneous settings. On the other hand, Tree‐dyn and Non‐Commut‐Tree‐dyn are fully dynamic algorithms, for commutative or non‐commutative reductions. We show that these algorithms are approximation algorithms with constant or asymptotic ratios. We assess the relative performance of all four non‐clairvoyant algorithms with heterogeneous costs through a set of simulations. Our conclusions hold for a variety of distributions. Copyright © 2014 John Wiley & Sons, Ltd.
Electrochemical Characterization of Gel Electrolytes for Aqueous Lithium‐Ion Batteries
Authors: Stojadinović Jelena , Dushina Anastasiya , Trócoli Rafael , La Mantia Fabio
Published: July 2014

The augmentation of the operating voltage span of water‐based electrolytes would render aqueous lithium‐ion batteries nearer to real application, as a substitute for high‐power lithium‐ion batteries. The possibility for improving the electrochemical stability window of the water‐based solutions 2 M Li2SO4 and 4 M LiClO4 by adding different gelling agents is investigated here by addressing the cathodic and anodic domains of the stability window separately. The conductivity of all electrolytes and the corresponding activity of water are determined using electrochemical impedance spectroscopy and mass spectrometry, respectively. The stability window is assessed by alternating high (±100 μA cm−2) and low (±10 μA cm−2) current densities in a chronopotentiometric mode, thereby simulating the self‐discharge performance of batteries under operating conditions. In the case of Li2SO4‐based solutions, the addition of gelling agents (carboxymethyl cellulose and agar) results in the enlargement of the stability window and in the reduction of the electrolyte ionic conductivity.
In situ studies of the spiral growth of zinc thiourea sulphate crystals with ethylene diamine tetraacetic acid doped by atomic force microscopy
Authors: Song Jie , Li Mingwei , Cheng Min , Hu Zhitao , Cao Yachao
Published: July 2014

Investigation of crystal growth under screw dislocation mechanisms on the (100) face of zinc tris (thiourea) sulphate (ZTS) crystals doped ethylene diamine tetraacetic acid (EDTA) has been carried out in a fluid cell by in situ atomic force microscopy (AFM). The generation of a dislocation spiral during the step advancing was observed. Through the measurement of the critical length of four sides of a rectangular spiral with a complete growth period, the advancement velocities, step edge free energies and kinetic coefficients of steps have been obtained. The changes in the step velocity with time have been studied. It was found that the relationship between the step velocity and step length is inconsistent with the previous report. The emergent points of dislocations do not disappear even though they are covered by either several elementary steps or macro‐steps. It is also shown that the interchange of two spirals whose emergent points of dislocations are adjacent will lead to a distortion of two contiguous steps and affect the growth rates of spirals. The obviously asymmetric growth of spirals of opposite sign in real time was observed. The coexistence and competition of dislocation spirals under different conditions was emphasized considering the activity of dislocation.
The growth and dislocation characterization of Yb0.005Y0.848Lu0.147VO4 mixed laser crystal
Authors: Shi‐ming Zhang , Bing Teng , De‐gao Zhong , Bing‐tao Zhang , Chao Wang , Yu‐yi Li , Li‐Ting Yang , Peng You
Published: July 2014

A new mixed laser crystal, Yb0.005Y0.848Lu0.147VO4, has been successfully grown using the Czochralski method. An ICP‐OES was used to measure the concentrations of elements (Yb, Y, Lu, V) in the crystal, and the chemical formula was determined. X‐ray powder diffraction analysis shows that the crystal has ZrSiO4 structure. A pair of edge dislocations with certain orientation was observed by the HREM, and the orientation was confirmed by the calibration of the diffraction spots. The formation mechanism of this type dislocation was given by analysis on structure and thermal expansion of crystal. The suggestion to avoid these dislocations was also given.
Possibility of analytical finding of glycerol caused by self‐catheterization in doping control
Authors: Okano Masato , Nishitani Yasunori , Kageyama Shinji
Published: July 2014

Glycerol is listed on the World Anti‐Doping Agency (WADA) prohibited list as a masking agent principally because the administration of glycerol increases plasma volume and decreases the concentration of haemoglobin and the value of haematocrit in blood. Glycerol is a naturally occurring substance; therefore, the threshold is set as 1.0 mg/mL in the WADA technical document (WADA TD2013DL). In a WADA‐accredited doping control laboratory, three doping control urine specimens collected from impaired athletes were determined to contain a high concentration of glycerol (>1.0 mg/mL); two of these specimens were considered adverse analytical findings (AAFs). Self‐catheterization is necessary for athletes with neurological disorders such as neurogenic bladder dysfunction. We conducted a simple simulation of self‐catheterization as an experimental test using urethral catheters with an antiseptic agent containing glycerol to confirm the influence of this antiseptic agent on the quantitative value of glycerol in doping control analysis. Some users employ a catheter with glycerol solution (ca. 1 mL) to avoid pain during use. The urine sample passed through such a catheter exhibited a glycerol concentration (4.94 mg/mL) greater than the threshold level. In September 2014, the threshold for glycerol will change from 1.0 to 4.3 mg/mL (WADA TD2014DL); however, a possibility exists for the quantitative value of glycerol in doping control analysis to exceed the threshold because of the use of an antiseptic agent containing glycerol for self‐catheterization. The AAF for glycerol for impaired athletes, particularly those who participate in Paralympic sports, should account for the use of a catheter with glycerol. Copyright © 2014 John Wiley & Sons, Ltd.