bluuebunny/crossref_metadata_2025 huggingface dataset:
Innovative Concept of Designing Primary Explosives by IntroducingPolymers: Preparation and Investigation of {[Ca(CHZ)2](ClO4)2}n (CHZ = carbohydrazide)
Authors: Mi Zhenhao , Chen Sitong , Jing Zhi , Yang Li , Zhang Tonglai
Published: July 2016

A novel alkaline‐earth metal perchlorate coordination polymer {[Ca(CHZ)2](ClO4)2}n (1, CHZ = carbohydrazide) was synthesized and characterized. The X‐ray single‐crystal diffraction results illustrate that the structure of the complex belongs to a tetragonal system, space group I‐42m. Every Ca2+ ion is octa‐coordinated with four CHZ groups. The CHZ group forms a tridentate coordination mode with different Ca2+ ions, leading to a coordination polymer structure. Therefore, the molecule is extended to a super 1D infinite polymer, and the configuration of the Ca2+ ion is a distorted dodecahedron. The DSC results show only one exothermal decomposition process with a peak temperature of 242.2 °C. The TG‐DTG curves demonstrate a 58 % mass loss from 210–290 °C and that finally 18 % of the polymer remains. Experimental data show that the combustion heat is –6.41 MJ kg–1 and the enthalpy of formation is –610.9 kJ mol–1. Non‐isothermal kinetic and thermodynamic parameters are obtained from Kissinger's method as well as Ozawa's method. The critical temperature of thermal explosion, ΔS≠, ΔH≠, and ΔG≠ are calculated as 234.7 °C, 134.1 J K–1 mol–1, 213.8 kJ mol–1, and 147.0 kJ mol–1, respectively. Additionally, the sensitivities towards impact and friction are assessed to be 0.5 J and 28 N from the relevant standard methods.
Reactivity of 1,2‐Diaza‐1,3‐dienes with Azomethine Ylides: [3+4] versus [3+2] Cycloadditions
Authors: Mantenuto Serena , Cayuelas Alberto , Favi Gianfranco , Attanasi Orazio A. , Mantellini Fabio , Nájera Carmen , Sansano José M.
Published: July 2016

The multicomponent 1,3‐dipolar cycloaddition of different 1,2‐diaza‐1,3‐dienes with in‐situ‐generated azomethine ylides produces 1,2,4‐triazepines or pyrrolidines by [3+4] or [3+2] cycloadditions, respectively. The regioselectivity is controlled by the electron‐withdrawing group bound to the azo moiety of the 1,2‐diaza‐1,3‐diene, which promotes exclusively the [3+4] cycloaddition. When the electron‐withdrawing group is replaced with a phenyl group, only a [3+2] cycloaddition occurs.
Enantioselective analysis of proteinogenic amino acids in cerebrospinal fluid by capillary electrophoresis–mass spectrometry
Authors: Prior Amir , Sánchez‐Hernández Laura , Sastre‐Toraño Javier , Marina Maria Luisa , de Jong Gerhardus J. , Somsen Govert W.
Published: July 2016

d‐Amino acids (AAs) are increasingly being recognized as essential molecules in biological systems. Enantioselective analysis of proteinogenic AAs in biological samples was accomplished by CE–MS employing β‐CD as chiral selector and ESI via sheath‐liquid (SL) interfacing. Prior to analysis, AAs were fully derivatized with FMOC, improving AA‐enantiomer separation and ESI efficiency. In order to optimize the separation and MS detection of FMOC‐AAs, the effects of type and concentration of CD in the BGE, the composition of the SL, and MS‐interfacing parameters were evaluated. Using a BGE of 10 mM β‐CD in 50 mM ammonium bicarbonate (pH 8) containing 15% v/v isopropanol, a SL of isopropanol‐water‐1 M ammonium bicarbonate (50:50:1, v/v/v) at a flow rate of 3 μL/min, and a nebulizer gas pressure of 2 psi, 15 proteinogenic AAs could be detected with enantioresolutions up to 3.5 and detection limits down to 0.9 μM (equivalent to less than 3 pg AA injected). The selectivity of the method was demonstrated by the analysis of spiked cerebrospinal fluid, allowing specific detection of d‐AAs. Repeatability and linearity obtained for cerebrospinal fluid were similar to standard solutions, with peak area and migration‐time RSDs (n = 5) below 16.2 and 1.6%, respectively, and a linear response (R2 ≥ 0.977) in the 3–90 μM range.
Thermal properties of polyethylene flame retarded with expandable graphite and intumescent fire retardant additives
Authors: Kruger Hermanus Joachim , Focke Walter Wilhelm , Mhike Washington , Taute Albertus , Roberson Albert
Published: July 2016

Low‐density polyethylene was flame retarded by combinations of expandable graphite with either ethylenediamine phosphate or 3,5‐diaminobenzoic acid phosphate. Cone calorimeter, laser pyrolysis, and open flame exposure tests (supported by video and infrared camera data capture and analysis) were conducted to assess ignition and burn behavior. Cone calorimeter results indicated substantial reductions in the peak heat release rates for all flame‐retarded samples but with reduced ignition times and increased flame out times. Smoke generation was suppressed in the presence of expandable graphite. Infrared and video data from open flame fire tests indicated cohesive bonding of expanded strings and thermal shielding properties in all binary systems. All binary systems delivered fire retardation exceeding any of the single fire retardant compounds. They were also able to withstand higher temperatures before ignition, burn through, or sag occurred. All ethylenediamine phosphate‐containing binary systems prevented sample burn through, maintaining structural integrity of samples until eventual melting of the polymer media occurred. Thermogravimetric analysis laser pyrolysis results confirmed the good thermal shielding imparted by the intumescent additives. Copyright © 2016 John Wiley & Sons, Ltd.
Chiral Separations using Miniaturized Techniques: State of the Art and Perspectives
Authors: Fanali Chiara , Fanali Salvatore
Published: July 2016

The separation and analysis of chiral compounds is an important topic of research, because these analytes are involved in various processes, e.g., biological, pharmacological, human health, etc. Their separation has also been recently obtained utilizing microfluidic techniques, such as capillary electrophoresis (CE), electrochromatography (CEC), and capillary/nano‐liquid chromatography (CLC/nano‐LC). Enantiomeric separation is mainly obtained by applying the direct resolution method, where a chiral selector (CS) is present in the separation system, either added to the mobile phase (MP) or bonded to the stationary phase or to the capillary wall. Among the several CSs used in microfluidic techniques, cyclodextrins, proteins, peptides, glycopeptide antibiotics, and modified polysaccharides are the most employed. Microfluidic techniques can offer several advantages over conventional analytical tools, e.g., high efficiency, high mass sensitivity, and reduced volumes of MP and sample. Optimized methods have been applied in different fields, such as biomedical, food chemistry, environment, pharmaceutical, etc. Excellent results have been achieved in CE and nano‐LC. Although CEC can offer higher efficiency due to the use of a strong electroosmotic flow, its use is less popular than the other. This limitation can be explained with the limited number of the stationary phases (SPs) commercially available.
Generation of Silicone Poly‐HIPEs with Controlled Pore Sizes via Reactive Emulsion Stabilization
Authors: Giustiniani Anaïs , Guégan Philippe , Marchand Manon , Poulard Christophe , Drenckhan Wiebke
Published: July 2016

Macrocellular silicone polymers are obtained after solidification of the continuous phase of a poly(dimethylsiloxane) emulsion, which contains poly(ethylene glycol) drops of sub‐millimetric dimensions. Coalescence of the liquid template emulsion is prohibited by a reactive blending approach. The relationship is investigated in detail between the interfacial properties and the emulsion stability, and micro‐ and millifluidic techniques are used to generate macrocellular polymers with controlled structural properties over a wider range of cell sizes (0.2–2 mm) and volume fractions of the continuous phase (0.1%–40%). This approach could easily be transferred to a wide range of polymeric systems.

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Surface Functionalization of Natural Rubber by UV‐Induced Thiol‐ene Chemistry
Authors: Manhart Jakob , Kramer Rebecca , Schaller Raimund , Holzner Armin , Kern Wolfgang , Schlögl Sandra
Published: July 2016

Natural rubber (NR) surfaces with tailored physicochemical properties and spatially controlled surface topology were prepared by exploiting radical‐mediated thiol‐ene chemistry. Selected functional thiols were immobilized onto NR surfaces by the photo‐induced addition reaction across the unsaturated CC double bonds of the cis‐1,4‐isoprene units. The modified elastomer surfaces are characterized by means of ATR FTIR spectroscopy to follow changes in the chemical surface composition, and by contact angle measurements to study changes in surface polarities. The results evidence the versatility of this photochemical functionalization route since different surface characteristics and surface reactivities were obtained, depending on the chemical nature of the attached thiol. In addition, the influence of the surface functionalization on bulk properties and surface morphology was determined by tensile tests and microscopic techniques, respectively. Results show that both tensile properties and surface morphology are not affected by the photochemical functionalization process. The immobilized thiols were further used as reactive anchor groups for a subsequent immobilization of inorganic silica particles, resulting in a well‐defined change in surface roughness and topology. Spatial control of surface properties was accomplished by photolithographic techniques that enabled a patterned immobilization of inorganic particles onto NR surfaces. Microscopic techniques revealed the selective coupling of the inorganic particles in the illuminated surface areas that were defined by high resolution and clear edges.
Calorimetric Investigations of Oriented Polypropylene Tapes and Self‐Reinforced Composites
Authors: Kościuszko Artur , Sterzyński Tomasz , Piszczek Kazimierz
Published: July 2016

Differential scanning calorimetry (DSC) is a commonly applied method of determining various physical properties of thermoplastic polymers. Analyzing DSC melting and crystallization curves it is possible to verify whether the macromolecules orientation occurs in fibers, films and self‐reinforced polymer composites (SRC). This paper presents the comparison of the results of calorimetric investigations of polypropylene (PP) single polymer composites (SRC) with the investigations of constrained PP tape samples additionally annealed before the measurement. The program of thermal treatment resembled temperature changes in the mold during SRC production by hot compaction method. The results confirmed a substantial influence of compression molding pressure on the melting process of oriented PP reinforcement used in the production of single polymer composites.
Measurement of Beer‐Lambert Attenuation Coefficient and Curing Kinetics Power Order: A Method Based on Rapid‐Scan FTIR During Laser Curing on an ATR
Authors: Li Wenlong , Batteux Florian , Araujo Steven , Delpouve Nicolas , Saiter Jean‐Marc , Tan Li , Negahban Mehrdad
Published: July 2016

When photo curing a polymer system, one immediately becomes concerned with the depth of penetration of light into the system and how it affects the uniformity of the curing process. The attenuation of light is related to the Beer‐Lambert law of light penetration into the system, and its influence on the curing depends on the role of light intensity on the curing kinetics. The attenuation coefficient of the Beer‐Lambert law can be measured by direct light power measurements for light passing through different thicknesses of the material. In this article we show how the curing kinetics measured by following changes in the infrared light spectra obtained from rapid‐scan FTIR can be used to obtain both the Beer‐Lambert attenuation coefficient and the power factor, indicating the nonlinear influence of the light power on the curing process. The method is demonstrated for the photo curing of an acrylate cross‐linker, and verified using direct power measurement.
MRI artifact correction using sparse + low‐rank decomposition of annihilating filter‐based hankel matrix
Authors: Jin Kyong Hwan , Um Ji‐Yong , Lee Dongwook , Lee Juyoung , Park Sung‐Hong , Ye Jong Chul
Published: July 2016

Purpose

Magnetic resonance imaging (MRI) artifacts are originated from various sources including instability of an magnetic resonance (MR) system, patient motion, inhomogeneities of gradient fields, and so on. Such MRI artifacts are usually considered as irreversible, so additional artifact‐free scan or navigator scan is necessary. To overcome these limitations, this article proposes a novel compressed sensing‐based approach for removal of various MRI artifacts.

Theory

Recently, the annihilating filter based low‐rank Hankel matrix approach was proposed. The annihilating filter based low‐rank Hankel matrix exploits the duality between the low‐rankness of weighted Hankel structured matrix and the sparsity of signal in a transform domain. Because MR artifacts usually appeared as sparse k‐space components, the low‐rank Hankel matrix from underlying artifact‐free k‐space data can be exploited to decompose the sparse outliers.

Methods

The sparse + low‐rank decomposition framework using Hankel matrix was proposed for removal of MRI artifacts. Alternating direction method of multipliers algorithm was employed for the minimization of associated cost function with the initialized matrices from a factorization‐based matrix completion.

Results

Experimental results demonstrated that the proposed algorithm can correct MR artifacts including herringbone (crisscross), motion, and zipper artifacts without image distortion.

Conclusion

The proposed method may be a robust correction solution for various MRI artifacts that can be represented as sparse outliers. Magn Reson Med 78:327–340, 2017. © 2016 International Society for Magnetic Resonance in Medicine
The influence of prolonged vibration on motor unit behavior
Authors: Mosier Eric M. , Herda Trent J. , Trevino Michael A. , Miller Jonathan D.
Published: July 2016

Introduction: The purpose of this study was to determine the effects of vibration (VIB) on motor unit (MU) behavior of the vastus lateralis (VL) muscle during a 40% maximal voluntary contraction (MVC). Methods: Eleven healthy (age 21.3 ± 2.6 years) individuals participated in the study. Surface electromyography (EMG) data were recorded from the VL during isometric trapezoidal muscle contractions at 40% MVC. Firing events of single MUs and EMG amplitude were reported for the first, middle, and final seconds of a 12‐second steady force segment at 40% MVC. VIB was applied at 55 Hz to the patellar tendon for 15 minutes before and continued throughout the remainder of testing (VIB) or remained off (CON). Results: There were significant increases in MU firing rates during VIB in comparison to CON and no differences in EMG amplitude between VIB and CON. Conclusion: The VIB‐mediated reduction in muscle spindle function altered MU behavior at 40% MVC. Muscle Nerve 55: 500–507, 2017
ReversePTP: A clock synchronization scheme for software‐defined networks
Authors: Mizrahi Tal , Moses Yoram
Published: July 2016

We introduce REVERSEPTP, a clock synchronization scheme for software‐defined networks (SDNs). REVERSEPTP is based on the Precision Time Protocol (PTP), but is conceptually reversed; in REVERSEPTP, all nodes (switches) in the network distribute timing information to a single software‐based central node (the SDN controller), which tracks the state of all the clocks in the network. Hence, all computations and bookkeeping are performed by the central node, whereas the ‘dumb’ switches are only required to periodically send it their current time. In accordance with the SDN paradigm, the ‘brain’ is implemented in software, making REVERSEPTP flexible and programmable from an SDN programmer's perspective. We present the REVERSEPTP architecture and discuss how it can be used in typical SDN architectures. Our experimental evaluation of a network with 34 REVERSEPTP‐enabled nodes demonstrates the effectiveness and scalability of using REVERSEPTP. Copyright © 2016 John Wiley & Sons, Ltd.
Physical activity, mental health, and weight gain in a longitudinal observational cohort of nonobese young adults
Authors: Staiano Amanda E. , Marker Arwen M. , Martin Corby K. , Katzmarzyk Peter T.
Published: July 2016

Objective

To investigate the relationship among moderate‐to‐vigorous physical activity (MVPA), mental health symptoms, and weight gain in young adults.

Methods

Fifty‐nine healthy men and women (age 26.8 ± 4.7 years, body mass index [BMI] 22.4 ± 2.3 kg/m2) were assessed at baseline and year 2. Weight, BMI, fat mass by dual‐energy X‐ray absorptiometry, anxiety and depression by the SCL‐90, and MVPA by accelerometry were assessed. Sex‐stratified linear regression models were used to examine associations between baseline anxiety/depression and body composition change, then repeated controlling for baseline MVPA.

Results

Overall, weight, BMI, fat mass, and subcutaneous adiposity significantly increased at year 2 (P < 0.05). For women, a higher depression and anxiety score predicted increased weight, BMI, fat mass, and subcutaneous adiposity (P < 0.05). Controlling for MVPA attenuated these associations to nonsignificance. For men, MVPA did not alter the associations between anxiety and increased weight, BMI, fat mass, and subcutaneous adiposity (P < 0.05) or the associations between depression and decreased weight, BMI, fat mass, and subcutaneous adiposity (P < 0.05).

Conclusions

Anxiety and depression were related to body composition change for young adults. In women, MVPA attenuated these associations to nonsignificance. MVPA may buffer the adverse effects of depression and anxiety symptoms on young women's weight gain.
A simple intrinsic measure for rapid crack propagation in bimodal polyethylene pipe grades validated by elastic–plastic fracture mechanics analysis of data from instrumented Charpy impact test
Authors: Deblieck Rudy A.C. , van Beek D.J.M. (Linda) , McCarthy Mary , Mindermann Petra , Remerie Klaas , Langer Beate , Lach Ralf , Grellmann Wolfgang
Published: July 2016

Conventional test procedures, such as the S4 test to analyze the resistance against rapid crack propagation (RCP) of plastic pipe materials are characterized by usage of a lot of material, are far from saving of time and they are‐in need of special experimental set‐ups. Therefore, in the last decade, small‐scale accelerated reliable tests (SMART) are developed ‐ worldwide to overcome the disadvantage of such conventional tests. In this article, fracture mechanics based analysis of instrumented Charpy impact test data for a set of bimodal high‐density polyethylene pipe grades are compared with data of the conventional Charpy impact test. From this comparison the Charpy impact strength at −30°C comes forth as a robust reproducible measure of the resistance to RCP and it is therefore proposed as a SMART method to rank materials with respect to RCP resistance. POLYM. ENG. SCI., 57:13–21, 2017. © 2016 Society of Plastics Engineers
Randomized controlled trial of the Valencia model of waking hypnosis plus CBT for pain, fatigue, and sleep management in patients with cancer and cancer survivors
Authors: Mendoza M.E. , Capafons A. , Gralow J.R. , Syrjala K.L. , Suárez‐Rodríguez J.M. , Fann J.R. , Jensen M.P.
Published: July 2016

Background

This study evaluated the efficacy of an intervention combining the Valencia model of waking hypnosis with cognitive‐behavioral therapy (VMWH‐CBT) in managing cancer‐related pain, fatigue, and sleep problems in individuals with active cancer or who were post‐treatment survivors. We hypothesized that four sessions of VMWH‐CBT would result in greater improvement in participants' symptoms than four sessions of an education control intervention. Additionally, we examined the effects on several secondary outcome domains that are associated with increases in these symptoms (depression, pain interference, pain catastrophizing, and cancer treatment distress).

Methods

The study design was a randomized controlled crossover clinical trial comparing the VMWH‐CBT intervention with education control. Participants (N = 44) received four sessions of both treatments, in a counterbalanced order (n = 22 per order condition).

Results

Participants were 89% female (N = 39) with mean age of 61 years (SD = 12.2). They reported significantly greater improvement after receiving the active treatment relative to the control condition in all the outcome measures. Treatment gains were maintained at 3‐month follow‐up.

Conclusions

This study supports the beneficial effects of the VMWH‐CBT intervention relative to a control condition and that treatment gains remain stable. VMWH‐CBT–trained clinicians should be accessible for managing symptoms both during and after cancer treatment, though the findings need to be replicated in larger samples of cancer survivors.
Production of bulk NV centre arrays by shallow implantation and diamond CVD overgrowth
Authors: Lesik Margarita , Raatz Nicole , Tallaire Alexandre , Spinicelli Piernicola , John Roger , Achard Jocelyn , Gicquel Alix , Jacques Vincent , Roch Jean‐François , Meijer Jan , Pezzagna Sébastien
Published: July 2016

The nanometer‐scale engineering of single nitrogen‐vacancy (NV) centres in diamond can be obtained by low‐energy (keV) nitrogen implantation with limited straggling. However, shallow NV centres (a few nanometres deep) generally have inferior overall properties than deeply implanted or deep native NV centres, due to the surface proximity. It has already been shown that the spin coherence time of shallow NVs is improved by overgrowth of a thin diamond layer. However the influence of the overgrowth on the survival, the optical properties and the charge state of the centres has not been studied in detail. In this article, we have overgrown three diamond samples (containing NV centres implanted at different depths) using different procedures. We show the successful overgrowth of a pattern of very shallow (2 nm) implanted NV centres using an optimised overgrowth process. Furthermore, the charge state of ensembles and single NV centres was found to be shifted from NV0 to NV− and stabilised in the negative charge state after overgrowth. The combination of low‐energy high‐resolution ion implantation and high‐purity chemical vapour deposition (CVD) overgrowth procedures opens the way towards the fabrication of scalable and efficient quantum devices based on single defects in diamond.

Left: implanted pattern of very shallow NV centres (depth ∼2 nm) using a pierced AFM tip. Right: same pattern after CVD overgrowth of a 4 μm‐thick diamond layer.
People Pillars: Re‐structuring the Toyota Production System (TPS) House Based on Inadequacies Revealed During the Automotive Recall Crisis
Authors: Kehr Thomas W. , Proctor Michael D.
Published: July 2016

Toyota has long been recognized as a leader in lean manufacturing and production quality through a dedicated practice of continuous process improvements and waste elimination techniques hallmarked within their Toyota Production System (TPS) and the ‘Toyota Way’ principles. Toyota's long list of successes and quality achievements has inspired companies within all industry sectors, not just automotive, to seek application of the coveted TPS into their process models in hopes of achieving the rewards that lean production promises. However, a recent series of automotive recall announcements associated with Toyota quality control have led many industry experts and students to reflect on possible inadequacies of the TPS House model. This article seeks to identify potential structural shortcomings and possible deficiencies of the TPS House in light of the root causes of recall crisis and suggest potential re‐structuring to better achieve continuous improvement. Copyright © 2016 John Wiley & Sons, Ltd.
Quantitation of α‐hydroxy acids in complex prebiotic mixtures via liquid chromatography/tandem mass spectrometry
Authors: Parker Eric T. , Cleaves H. James , Bada Jeffrey L. , Fernández Facundo M.
Published: July 2016

Rationale

Spark discharge experiments, like those performed by Stanley Miller in the 1950s, generate complex, analytically challenging mixtures that contain biopolymer building blocks. Recently, α‐amino acids and α‐hydroxy acids (AHAs) were subjected to environmental cycling to form simple depsipeptides (peptides with both amide and ester linkages). The synthesis of AHAs under possible primordial environments must be examined to better understand this chemistry.

Methods

We report a direct, quantitative method for AHAs using ultrahigh‐performance liquid chromatography and triple quadrupole mass spectrometry. Hexylamine ion‐pairing chromatography and selected reaction monitoring detection were combined for the rapid analysis of ten AHAs in a single run. Additionally, prebiotic simulation experiments, including the first‐ever reproduction of Miller's 1958 cyanamide spark discharge experiment, were performed to evaluate AHA synthesis over a wide range of possible primitive terrestrial environments.

Results

The quantitating transition for each of the AHAs targeted in this study produced a limit of detection in the nanomolar concentration range. For most species, a linear response over a range spanning two orders of magnitude was found. The AHAs glycolic acid, lactic acid, malic acid, and α‐hydroxyglutaric acid were detected in electric discharge experiments in the low micromolar concentration range.

Conclusions

The results of this work suggest that the most abundant building blocks available for prebiotic depsipeptide synthesis would have been glycolic, lactic, malic, and α‐hydroxyglutaric acids, and their corresponding amino acids, glycine, alanine, and aspartic and glutamic acids. Copyright © 2016 John Wiley & Sons, Ltd.
A small molecule inhibitor of mutant IDH2 rescues cardiomyopathy in a D‐2‐hydroxyglutaric aciduria type II mouse model
Authors: Wang Fang , Travins Jeremy , Lin Zhizhong , Si Yaguang , Chen Yue , Powe Josh , Murray Stuart , Zhu Dongwei , Artin Erin , Gross Stefan , Santiago Stephanie , Steadman Mya , Kernytsky Andrew , Straley Kimberly , Lu Chenming , Pop Ana , Struys Eduard A. , Jansen Erwin E. W. , Salomons Gajja S. , David Muriel D. , Quivoron Cyril , Penard‐Lacronique Virginie , Regan Karen S. , Liu Wei , Dang Lenny , Yang Hua , Silverman Lee , Agresta Samuel , Dorsch Marion , Biller Scott , Yen Katharine , Cang Yong , Su Shin‐San Michael , Jin Shengfang
Published: July 2016

D‐2‐hydroxyglutaric aciduria (D2HGA) type II is a rare neurometabolic disorder caused by germline gain‐of‐function mutations in isocitrate dehydrogenase 2 (IDH2), resulting in accumulation of D‐2‐hydroxyglutarate (D2HG). Patients exhibit a wide spectrum of symptoms including cardiomyopathy, epilepsy, developmental delay and limited life span. Currently, there are no effective therapeutic interventions. We generated a D2HGA type II mouse model by introducing the Idh2R140Q mutation at the native chromosomal locus. Idh2R140Q mice displayed significantly elevated 2HG levels and recapitulated multiple defects seen in patients. AGI‐026, a potent, selective inhibitor of the human IDH2R140Q‐mutant enzyme, suppressed 2HG production, rescued cardiomyopathy, and provided a survival benefit in Idh2R140Q mice; treatment withdrawal resulted in deterioration of cardiac function. We observed differential expression of multiple genes and metabolites that are associated with cardiomyopathy, which were largely reversed by AGI‐026. These findings demonstrate the potential therapeutic benefit of an IDH2R140Q inhibitor in patients with D2HGA type II.
Cholic acid therapy in Zellweger spectrum disorders
Authors: Berendse Kevin , Klouwer Femke C. C. , Koot Bart G. P. , Kemper Elles M. , Ferdinandusse Sacha , Koelfat Kiran V. K. , Lenicek Martin , Schaap Frank G. , Waterham Hans R. , Vaz Frédéric M. , Engelen Marc , Jansen Peter L. M. , Wanders Ronald J. A. , Poll‐The Bwee Tien
Published: July 2016

Introduction

Zellweger spectrum disorders (ZSDs) are characterized by a failure in peroxisome formation, caused by autosomal recessive mutations in different PEX genes. At least some of the progressive and irreversible clinical abnormalities in patients with a ZSD, particularly liver dysfunction, are likely caused by the accumulation of toxic bile acid intermediates. We investigated whether cholic acid supplementation can suppress bile acid synthesis, reduce accumulation of toxic bile acid intermediates and improve liver function in these patients.

Methods

An open label, pretest‐posttest design study was conducted including 19 patients with a ZSD. Participants were followed longitudinally during a period of 2.5 years prior to the start of the intervention. Subsequently, all patients received oral cholic acid and were followed during 9 months of treatment. Bile acids, peroxisomal metabolites, liver function and liver stiffness were measured at baseline and 4, 12 and 36 weeks after start of cholic acid treatment.

Results

During cholic acid treatment, bile acid synthesis decreased in the majority of patients. Reduced levels of bile acid intermediates were found in plasma and excretion of bile acid intermediates in urine was diminished. In patients with advanced liver disease (n = 4), cholic acid treatment resulted in increased levels of plasma transaminases, bilirubin and cholic acid with only a minor reduction in bile acid intermediates.

Conclusions

Oral cholic acid therapy can be used in the majority of patients with a ZSD, leading to at least partial suppression of bile acid synthesis. However, caution is needed in patients with advanced liver disease due to possible hepatotoxic effects.
Spatiotemporal characteristics of atrial fibrillation electrograms: A novel marker for arrhythmia stability and termination
Authors: Thanigaimani Shivshankar , Brooks Anthony G. , Kuklik Pawel , Twomey Darragh J. , Franklin Samantha , Noschka Erik , Chapman Darius , Pathak Rajeev K. , Mahajan Rajiv , Sanders Prashanthan , Lau Dennis H.
Published: July 2016

Background

Sequentially mapped complex fractionated atrial electrograms (CFAE) and dominant frequency (DF) sites have been targeted during catheter ablation for atrial fibrillation (AF). However, these strategies have yielded variable success and have not been shown to correlate consistently with AF dynamics. Here, we evaluated whether the spatiotemporal stability of CFAE and DF may be a better marker of AF sustenance and termination.

Methods

Eighteen sheep with 12 weeks of “one‐kidney, one‐clip” hypertension underwent open‐chest studies. A total of 42 self‐terminating (28–100 s) and 6 sustained (>15 min) AF episodes were mapped using a custom epicardial plaque and analyzed in 4‐s epochs for CFAE, using the NavX CFE‐m algorithm, and DF, using a Fast Fourier Transform. The spatiotemporal stability index (STSI) was calculated using the intraclass correlation coefficient of consecutive AF epochs.

Results

A total of 67,733 AF epochs were analyzed. During AF initiation, mean CFE‐m and the STSI of CFE‐m/DF were similar between sustained and self‐terminating episodes, although median DF was higher in sustained AF (p=0.001). During sustained AF, the STSI of CFE‐m increased significantly (p=0.02), whereas mean CFE‐m (p=0.5), median DF (p=0.07), and the STSI of DF remained unchanged (p=0.5). Prior to AF termination, the STSI of CFE‐m was significantly lower (p<0.001), with a physiologically non‐significant decrease in median DF (−0.3 Hz, p=0.006) and no significant changes in mean CFE‐m (p=0.14) or the STSI of DF (p=0.06).

Conclusions

Spatiotemporal stabilization of CFAE favors AF sustenance and its destabilization heralds AF termination. The STSI of CFE‐m is more representative of AF dynamics than are the STSI of DF, sequential mean CFE‐m, or median DF.
A multicenter study of the need of additional freezing for cryoballoon ablation in patients with atrial fibrillation: The AD‐Balloon study
Authors: Miyamoto Koji , Doi Atsushi , Amaya Naoki , Morita Yoshiaki , Noda Takashi , Asakura Masanori , Hamasaki Toshimitsu , Tada Hiroshi , Takagi Masahiko , Yasuda Satoshi , Kusano Kengo
Published: July 2016

Background

Pulmonary vein isolation (PVI) is a cornerstone of catheter ablation in patients with paroxysmal atrial fibrillation (PAF), and balloon‐based ablation has been recently performed worldwide. Ablation using the second‐generation cryoballoon (CB2) (Arctic Front AdvanceTM, Medtronic, MN, USA) is useful for PVI; however, there is some debate concerning the optimal freezing time and number of cycles after PVI is achieved.

Methods

The AD‐Balloon study was designed as a prospective, multicenter, randomized clinical trial to evaluate the optimal strategy (freezing cycles) of CB2 ablation (UMIN Clinical Trials Registry UMIN000020130). The main objective of this study is to investigate the need for an additional freezing cycle after PVI in patients treated with CB2 ablation. Patients will be randomly assigned in a 1:1 ratio to treatment with additional freezing (AD group) or without additional freezing (non‐AD group). In the AD group, 3 min of additional freezing time will be applied in all pulmonary veins after PVI is confirmed at the previous freezing cycle. In the non‐AD group, no additional freezing will be applied in all pulmonary veins after PVI is confirmed. The primary endpoint of this study is the occurrence of atrial tachyarrhythmias within a 1‐year follow‐up period. We will enroll 110 consecutive patients with PAF. We will also investigate the usefulness of delayed‐enhancement magnetic resonance imaging to assess the ablation lesions caused by CB2 ablation.

Results

The results of this study are currently under investigation.

Conclusion

The AD‐Balloon study would assess the need for an additional freezing cycle after PVI is achieved. Our findings may contribute to further improvement of the CB2 ablation procedure.
L’incidence de l’hypotension post-intubation endotrachéale chez des patients en salle de réanimation: impact des définitions
Authors: Lévesque Marie-Claire , Le Sage Natalie , Berthelot Simon , Boucher Valérie , Mercier Éric , Émond Marcel
Published: July 2016

Objectif

Notre objectif primaire est de mesurer l’incidence d’HPI selon quatre définitions différentes retrouvées dans la littérature. Notre principal objectif secondaire est d’évaluer l’impact de la présence d’instabilité hémodynamique avant l’intubation sur l’incidence d’HPI. Le deuxième objectif secondaire consiste à déterminer l’incidence de l’HPI en fonction de l’intervalle de temps durant lequel la première hypotension survient.

Méthode

Une cohorte prospective a été constituée par les patients intubés en salle de réanimation à l’hôpital de l’Enfant-Jésus entre le 28/06/2011 et le 12/07/2012. L’HPI était globalement définie comme ≥1 mesure de tension artérielle systolique <90 mmHg suivant l’intubation. Les différentes définitions étudiées faisaient varier le temps de mesure de la tension artérielle (TA) après l’intubation, soit 1) jusqu’à 5 minutes, 2) jusqu’à 15 minutes, 3) jusqu’à 30 minutes et 4) en tout temps lors du séjour en salle de réanimation.

Résultat

Au cours de la période à l’étude, 155 patients ont été intubés sur place dont 81 patients qui répondaient aux critères d’inclusion. L’incidence de l’HPI pour chaque définition est respectivement de 9.9%, 18.5%, 24.7% et 28.4%. La comparaison entre chacune de ces incidences révèle une différence statistiquement significative (p<0.05), à l’exception des deux dernières. L’incidence cumulative d’HPI à tout moment suivant l’intubation chez les patients présentant une hypotension pré-intubation est de 62.5% (IC 95% 28.5-87.5) en opposition aux patients hémodynamiquement stables en pré-intubation qui présentaient une incidence d’HPI de 24.7% (IC 95% 16.1-35.8).

Conclusion

L’hypotension post-intubation est un effet indésirable fréquent chez les patients au département d’urgence et son incidence varie de façon significative en fonction de la définition temporelle utilisée au sein d’une même cohorte de patients.
South Africa's Strategic Vulnerabilities: The ‘Citadel Assumption’
Authors: Baker Pauline H.
Published: July 2016

In assessing the patterns of conflict in southern Africa, it is commonplace to stress the theme of South Africa's overwhelming strengths against the threat of black nationalist forces. Most observers support this thesis of South African invulnerability by citing the country's enormous mineral resources, impressive military capabilities, continuing strategic importance and economic links with the west. Leonard Thompson (in Thompson and Butler, 1975: 408) ably summarized this popular view, citing other noteworthy domestic and international variables to buttress the point:

In resisting “terrorists” South Africa's government has the ardent support of four million Whites who consider their very survival is at stake. South Africa has a far more powerful industrial base and far more formidable military equipment than any government that has been overthrown by guerrilla forces. It has the capacity to produce atomic weapons; the terrain in the vicinity of its borders is treeless or sparsely wooded savanna, which affords guerrillas scant opportunity for concealment. Moreover, the South African revolutionaries in exile are divided into rival factions; the capacity of Black African states to launch military expeditions against the Republic is limited by domestic economic and political weaknesses, interstate rivalries, and serious logistic problems; and neither the Soviet Union nor the People's Republic of China seems prepared to make a major commitment in southern Africa in the near future. Consequently, although guerrilla groups launched across South Africa's land frontiers may become a continual irritant to the regime, they do not seem likely to be able to overthrow it.
Challenges Facing African Universities: Selected Issues
Authors: Sawyerr Akilagpa
Published: July 2016

With notable exceptions, modern university education in Africa is a phenomenon of the last half century. Universities were established either immediately before or within a decade after political independence in most African countries. Since then, both the number of institutions and enrollment have expanded rapidly and continuously across the continent. The coverage of university education, nevertheless, remains inadequate for the needs of the knowledge society. With the relative decline of state support during the severe economic crisis of the 1980s, Africa's universities suffered substantial deterioration: overcrowding, infrastructure deficiencies, and inadequate access to international knowledge resources. These deficiencies led to problems of access, equity, quality, and relevance, and to an aging faculty. At the same time, higher education systems were complicated by the diversification of categories of student, types of institutions, and the kinds of knowledge demanded. In the resulting situation of institutional complexity and policy dynamism, Africa's universities were compelled to develop strategies for coping and innovation. The result has been a halt in the decline in many instances, and revival and growth in several others. Accompanying these positive results, however, have been new forms of social exclusion as well as a loss of focus on the public purpose of universities as institutions concentrate mainly on increasing institutional incomes and producing graduates for the labor market. To address these and other problems, it is necessary to insist on the irreducible responsibility of the state for the maintenance of the higher education system and the need for a proper focus on the public purposes of higher education. Systems-level policy frameworks need to be negotiated and established to guide the strategic choices that have to be made by all players in the education sector.
The Promise of Partnership and Continuities of Dependence: External Support to Higher Education in Africa
Authors: Samoff Joel , Carrol Bidemi
Published: July 2016

After a period of conscious neglect and dramatic deterioration, higher education in Africa is again attracting external attention, with an emphasis now on “partnerships” rather than “aid.” This report is based on an extensive survey of links between African institutions of higher education and foreign governments, foundations, and universities, with particular emphasis on links with the United States. In it, we explore the evolution, characteristics, promise, and problems of external support. Earlier, most African universities were linked to European institutions. With independence, they asserted their sovereignty and autonomy. By the 1980s, however, resources were inadequate nearly everywhere. Today, renewed attention may bring new funds, yet it also may bring new problems. Academic partnerships are often one-sided, and external support commonly carries conditions. By framing, organizing, and orienting the academic enterprise and thus ways of knowing and validating knowledge, partnerships threaten to reintroduce, in both explicit and subtle ways, the external direction of the earlier era. A consideration of these and other issues is followed by several appendixes, which contain a thorough cataloging of this material and may be used as a resource for future research.
Juju and Justice at the Movies: Vigilantes in Nigerian Popular Videos
Authors: McCall John C.
Published: July 2016

This article examines the rise of vigilantism in southeastern Nigeria. Two opposing discourses on Nigerian vigilantism are examined. The first is characterized by the valorization of vigilantes as heroes in popular Nigerian video movies. The second is represented by a recent Human Rights Watch (HRW) report denouncing die vigilantes as criminals. My research utilizes ethnographic research to contextualize the video movies as a means toward understanding the ideological gap between these discourses. A close analysis of theIssakabavideo series reveals a subtle treatment of the vigilante phenomenon designed to appeal to an indigenous perspective that is cognizant of the inherent risks of vigilante justice but also aware of the limitations of reform strategies such as those proposed by the HRW report.
Media Accountability and Democracy in Nigeria, 1999–2003
Authors: Olukoyun Ayo
Published: July 2016

This article discusses the role of the media in Nigeria's Fourth Republic between 1999 and 2003. Employing a case study approach, it highlights as well as analyzes the media's role in insisting on accountability and decency in Nigeria's notoriously corrupt public life. The media's crusade ran against the country's geopolitical divisions and revived the debate on the national question as well as the media's own morality. The article draws on both primary and secondary data to examine the media's role in an emergent democracy.
Documentation on the Afro-American: Familiar and Less Familiar Sources
Authors: Porter Dorothy
Published: July 2016

On the evening of March 20, 1828, a group of free men of color organized a society that had as its purpose “the mental improvement of the people of color in the neighborhood of Philadelphia.” This organization was to be known as the “Reading Room Society.” Immediately a library was established and the librarian instructed to lend books to members for no longer than a week. Books were to be withdrawn or returned at the society's weekly meeting. Freedoms Journal, the earliest Negro newspaper, the first issue of which appeared in March, 1827, and Lundy's Genius of Universal Emancipation, an antislavery publication, were among the first works circulated. In May, 1833, the Philadelphia Library Company of Colored Persons appealed for “such books and other donations as will facilitate the object of this institution.” By 1838, this library had 600 volumes. Since Negroes could not enjoy the same privileges as whites in libraries, they established for themselves some 45 literary societies between 1828 and 1846 in several large cities, mainly in the East, most of which maintained reading rooms and circulating libraries.

As a consequence of these activities many Negroes were stimulated to assemble private libraries. In 1838, in Philadelphia and nearby cities, there were 8333 volumes in private libraries. In New York City, David Ruggles, a Negro abolitionist, pamphleteer, and printer, was probably the first Negro book collector. He maintained a circulating library and made antislavery and colonization publications available to many readers. He charged a fee of less than twenty-five cents a month for renting books relating to the Negro and slavery.
New African Studies Centers: A UCLA/Hew Pilot Program
Authors: Povey John F.
Published: July 2016

There has been considerable discussion recently in recognition of the need to develop African studies in this country on a far wider basis than at present, where it is concentrated too narrowly in a few major centers of great academic strength. Such discussion has been exacerbated by the demands of Afro-Americans whose concern for African studies is not less significant for the debatable academic basis upon which it is posited.

The problem with all previous programs to inaugurate new African programs has been that they focused totally upon the training of faculty. There have been a series of summer courses, many of which have in themselves been of high quality and substantially imaginative. Yet they did little to innovate new programs on the campus, owing to the sluggishness of the administrative machinery or the relative indifference to the new faculty interest. The program which the African Studies Center at the University of California at Los Angeles planned for the summers of 1968 and 1969 attempted to remedy this deficiency. The project was financed by the Department of Health, Education and Welfare under National Defense Education Act funds and was organized and administered by Michael F. Lofchie and John F. Povey, themselves joint assistant directors of the UCLA African Studies Center.
Further Additions to Materials for West African History in the Archives of Belgium and Holland by Patricia Carson
Authors: Feinberg H. M.
Published: July 2016

This article is a supplement to a previous article on the same subject published in the African Studies Bulletin. Before I list further citations omitted from Materials for West African History in the Archives of Belgium and Holland, I will discuss, in some detail, the nature of the archival material deposited in the Algemeen Rijksarchief, The Hague. I will attempt to enhance the brief discussions of Miss Carson while avoiding repetition of statements which seem clear and/or are adequately discussed in her book.

The General State Archives, The Hague, includes two major collections of interest to the West African historian: the Archives of the West India Companies and the Archives of the Netherlands Settlements on the Guinea Coast. Initially, one must realize that most of the seventeenth-century papers of both collections have been lost or destroyed, and that as a consequence there are many gaps among the existing manuscripts. For example, volume 81 (1658-1709) of the Archives of the Netherlands Settlements on the Guinea Coast includes only manuscripts for the following times: December 25, 1658-June 12, 1660; August, 1693; and October 12-December 31, 1709. Also, most of the seventeenth-century material is written in script, whereas the eighteenth-century manuscripts, with some exceptions, are in more conventional hand-writings.
Theses on Africa Accepted by Howard University Washington, D.C.
Authors: Garlick Peter C.
Published: July 2016

The following is a list of all known theses on African subjects accepted by Howard University up to and including June 1968. The earliest is dated 1936. The main sources of information were Howard University Library, whose lists are incomplete, and individual departments, most of which have inadequate records. There may, therefore, be omissions and inaccuracies. The arrangement here follows as closely as possible that in United States and Canadian Publications on Africa in 1965, Hoover Institution, Bibliographical Series, XXXIV, Stanford University, 1967. Theses are listed in alphabetical order by country, and, under each country, in alphabetical order of the writers'names.

It is hoped that other African Studies Centers will follow the lead of this article and make available lists of theses produced by their graduate students.