bluuebunny/crossref_metadata_2025 huggingface dataset:
Some Recent Developments in NMR Approaches for Studying Liquid Molecular Dynamics and Their Biological Applications
Authors: Price William S. , Hwang Lian‐Pin
Published: June 2015

Two aspects of NMR relaxation are reviewed and their use in studying molecular dynamics in the liquid state and their application to biological systems are discussed. The first aspect concerns the use of ‘null‐point spectra’ for observing the effects of higher rank multipoles (tensors) in the relaxation of quadrupolar nuclei. The second aspect concerns the effects of cross‐correlation in homo‐ and heteronuclear spin systems. The application of null point spectral analysis to study cross‐correlation in homonuclear spin systems is also discussed. Analysis of the effects of higher rank multipoles and of cross‐correlation effects are shown to provide substantially more structural and motional information about spin systems than that available from traditional relaxation measurements. While similar in information content to multiple quantum techniques, the null point technique is experimentally less demanding. Over the past several years, work in this laboratory has been heavily involved in the theoretical formulation and the application of these techniques to biological systems. Illustrations of the use of these techniques to biological systems are drawn from our recent work.
Imaging Techniques in Experiments on Dynamics
Authors: Chen Kuo‐Mei , Kuo Chen‐Nan
Published: June 2015

Spatial distributions of dynamic systems with resolved translational energy and selected internal states provide indispensable information about the corresponding physical and chemical mechanisms. From an experimental viewpoint, two‐dimensional imaging techniques are well suited to explore dynamic aspects of collisional processes. The advantages of imaging techniques over conventional methods are demonstrated in laser ablation of metal targets and collisionally induced electronic excitation of metal atoms. Approaching the ultimate goal in chemical dynamics, a unique method which combines laser‐induced fluorescing illumination and gated two‐dimensional imaging techniques can directly measure the three‐dimensional distributions of number density, angle and velocity of scattered products from photofragmentation and from inelastic and reactive collisions in the center‐of‐mass frame. The physical principle behind this direct method and its experimental arrangement are outlined.
Dynamics and Kinetics of Metal Atoms in the Gas Phase
Authors: Lin King‐Chuen
Published: June 2015

The review is divided into four sections. We first consider the varied behavior of K n2S and n2D states in their chemical reactivity and physical characterization. We review the effect of orbital alignment of an electronically excited metal atom on the cross section of energy transfer or chemical reaction, and report the technique of a single supersonic jet employed to measure this effect on the Ca spin‐changing collision. We discuss the effects of temperature and isotopic mass on the distribution of rotational quantum number of the product MgH to identify the reaction mechanism of Mg(1P1) + H2. The final concerns are the quantum yield, fine‐structure branching ratio and rate of collisional mixing for the K 2PJ doublets following photodissociation of KI at 193 nm.
New Aspects Concerning Chelating Resins
Authors: Liu Chuen‐Ying
Published: June 2015

Object of the present paper is to provide an up‐to‐date overview the application of chelating resins, a functional polymer of a special kind. Attention has been in particular limited to the field of ligand exchange chromatography, sample handling and trace enrichment, metal‐ion buffers and polymer catalysts with enzyme‐like activities. The fundamental principles in the design and syntheses of chelating resins for usage in these respects are also described.
Chemistry of Heterometallic Cluster Compounds Prepared by Condensation of Group 6 Metal Acetylide and Group 8 Binary Carbonyl Complexes
Authors: Chi Yun
Published: June 2015

The chemistry of trinuclear and tetranuclear heterometallic acetylide complexes, LWOs3(CO)11(CCR) and LWM2(CO)8(CCR), L = Cp and Cp*; M = Os and Ru, is presented. Included in this account are syntheses, characterization and reactivity, with a particular focus on reactions with disubstituted alkyne molecules. The reactivity and fluxionality of these acetylide complexes provides a plausible model for ligand‐mediated metal‐core rearrangement and the transformation of small organic molecules on catalytic metal surfaces.
Syntheses of Iso‐Condensed Heteroaromatic Pyrroles
Authors: Sha Chin‐Kang , Tsou Chiu‐Peng , Tsai Chung‐Yin , Liu Jia‐Ming , Lee Ren‐Sheng , Li Yu‐Chang , Tsai Fu‐Yuan , Way Shiow‐Jye , Young Jenn‐Jong , Chuan Kuang‐Sein , Yeh Ren‐Hwa
Published: June 2015

Three novel reactions for the synthesis of iso‐condensed heteroaromatic pyrroles: (1) tandem intramolecular 1,3‐dipolar cycloaddition and cycloreversion reaction; (2) phosphineimine‐alkylidenemalonate cyclization reaction; (3) retromalonate addition reaction, are described. They can be used in acidic, neutral or basic conditions respectively. Iso‐condensed heteroaromatic pyrroles, such as pyrrolo[3,4‐b]indole 12, pyrrolo[3,4‐b]pyridine 17, pyrrolo[3,4‐c]pyridine 18, thieno[2,3‐c]pyrrole 37, pyrrolo[3,4‐b]pyrrole 40, pyrrolo[3,4‐b]pyrazine 49, benzofuro[2,3‐c]pyrrole 50, 1,2‐bis[5‐thieno[2,3‐c]pyrrolyl]ethane 51, 1,4‐bis[5‐thieno[2,3‐c]pyrrolyl]benzene 52, dipyrrolo[3,4‐b;3′,4′‐d]dipyrroles 55 and 56, benzotripyrroles 62–64, and thieno[3,4‐c]pyrroles 67 and 73 are synthesized efficiently according to these methods.
Chemistry of Sydnone Compounds
Authors: Kuo Chao‐Nan , Wang Shao‐Pin , Yeh Mou‐Yung , Tien Hsien‐Ju
Published: June 2015

A review of sydnone chemistry is divided into two major parts, describing methods developed to prepare sydnone derivatives and syntheses starting from sydnones. Spectral studies of the structural characterization of sydnones are summarized in the conclusion.
Chemosystematic Correlations of Taiwanese Hepaticae
Authors: Wu Chia‐Li
Published: June 2015

Significance from the chemotaxonomic viewpoint is discussed on the basis of previous studies and recent findings on the chemical constituents of Taiwanese liverworts.
Chemical Activation of Amides to Their Mutagenic and Carcinogenic Derivatives
Authors: Lin Jen‐Kun
Published: June 2015

Most amides are stable compounds, but they are convertible to extremely reactive metabolites by microsomal enzymes. The amide drugs phenacetin and acetaminophen are converted to the toxic metabolite N‐acetyl‐p‐benzoquinoneimine by a combination of several cytochrome P‐450 systems. The well known hepatocarcinogen 2‐acetylaminofluorene (AAF) is metabolically activated to a highly electrophilic reactant that interacts with DNA, RNA and proteins. There are other alternative pathways which may actviate these amide compounds; nitrosation of these amides yield several directly acting mutagens, teratogens and carcinogens. We have synthesized several new N‐nitroso compounds, namely N‐nitrosophenacetin, N‐nitrosoacetaminophcn and N‐nitroso‐2‐acetylaminofluorene (NO‐AAF). The chemical structures of these compounds were characterized by spectrometric analysis of their naphthol‐coupling derivatives. The new compounds are highly mutagenic to Salmonella tester strains TA 97, TA 98, TA 100 and TA 1538 and require no microsomal metabolic activation. NO‐AAF in TA 98 is more mutagenic than MNNG and N‐acetoxy‐AAF. The teratogenic potentials of NO‐AAF and N‐nitrosophenacetin were studied with white Leghorn chick embryo. A high incidence of flaccid paralysis of the legs and a low incidence of feather, claw and bill malformations were found in the treated group; no such malformed embryos were found in the control group. Both N‐nitrosophenacetin and NO‐AAF are strong electrophiles and react readily with amino acids, nucleosides, nucleic acids and proteins at neutral pH. Our data indicated that NO‐AAF is a directly acting hepatocarcinogen in Sprague‐Dawley rats. NO‐AAF seems to be a directly acting mutagen, teratogen and probably a carcinogen of new prototype.
Kinetic and Structural Approaches to Enzyme Chemistry
Authors: Chang Gu‐Gang
Published: June 2015

In this review I summarize the research conducted in this enzymology laboratory. It includes purification, multiple forms, assay, activity‐staining, specificities, kinetics, modification, structure, mechanism, and regulation of the following enzymes: methionine S‐adenosyltransferase, aminoacyl‐tRNA synthetases, malic enzyme, alkaline phosphatase, acid phosphatase, and taxon‐specific crystallins.
Structural Characterization of Lens Crystallins and the Perspectives on the Evolution and Biosynthetic Applications of Enzymatic Crystallins
Authors: Chiou Shyh‐Horng
Published: June 2015

This account describes work in our laboratory on lens crystallins during the past decade. The major classes of crystallins are reviewed. A systematic and detailed analysis of the kinetic properties of two presumably structural proteins with stable enzymatic activities revealed subtle differences in kinetic mechanisms of these enzyme crystallins and their corresponding cellular enzymes. Bioorganic synthesis based on ϵ‐ and δ‐crystallins isolated from avian and reptilian lenses, two crystallins possessing lactate dehydrogenase and argininosuccinate lyase respectively, provides an efficient and practical tool for enantioselective synthesis of valuable organic intermediates. Understanding the crystallin diversity at the molecular and cellular levels constitutes a major goal of crystallin research, as it provides the framework to unravel the complex process underlying the evolution of lens crystallins in general and may provide insight into their biological significance.
Chemistry of Snake Neurotoxins and Future Perspectives
Authors: Yang C. C.
Published: June 2015

A historical review on the study of snake neurotoxins is presented, with special emphasis on the author's contributions in unraveling the chemistry of one of the most lethal non‐enzymatic protein factors. Cobrotoxin, a postsynaptic neurotoxin isolated in a crystalline state from the venom of Taiwan cobra, binds specifically to the nicotinic acetylcholine receptors on the postsynaptic membrane and thus blocks the neuromuscular transmission. It is a small basic protein consisting of a single peptide chain of 62 aminoacid residues, crosslinked by four disulfide bonds. The disulfide bonds and Tyr‐25 which are buried in the molecule form a central core to maintain and stabilize the active conformation of the toxin. Selective and stepwise chemical modifications of cobrotoxin indicate that at least two cationic groups, an ϵ‐amino group of Lys‐47 and a guanidino group of Arg‐33, both of which are common to all known postsynaptic snake neurotoxins, held at a certain critical distance in the molecule, are functionally important for its neuromuscular blocking activity.

Neurotoxins of another type exist in some common cobras or sea snakes. These presynaptic neurotoxins are basic phospholipase A2 (PLA2) per se or contain basic PLA2 as an indispensable part of their structures. Presynaptic PLA2 neurotoxins show both PLA2 activity and presynaptic neurotoxicity. Chemical modification of two highly potent presynaptic neurotoxins β1‐bungarotoxin and notexin was undertaken in the hope of elucidating the molecular features contributing to the biological activities of presynaptic PLA2 neurotoxins. Modification of tyrosine residues differentially influences the enzymatic activity and lethal toxicity of β1‐bungarotoxin and notexin, revealing that these toxins might possess two functional sites, one being responsible for the catalytic activity and the other for their pharmacological properties.
Development of a Novel Urine Alzheimer‐Associated Neuronal Thread Protein ELISA Kit and Its Potential Use in the Diagnosis of Alzheimer's Disease
Authors: Ma Lina , Wang Rong , Han Ying , Sheng Shuli , Zhu Jianan , Ji Zhijuan , Zhao Zhiwei , Cao Ziqing , Wang Peichang
Published: June 2015

Background

Alzheimer's disease (AD) is an age‐related chronic degenerative disease that damages the nervous system. A noninvasive and simple method for early detection of AD is extremely important for the diagnosis and prognosis of AD. Thus, we aimed to develop an enzyme‐linked immunosorbent assay (ELISA) kit to detect urine Alzheimer‐associated neuronal thread protein (AD7C‐NTP), and to evaluate its clinical value for the diagnosis of AD.

Methods

Immunogenic AD7C‐NTP peptide fragments were synthesized by the solid‐phase method and used for immunizing mice or rabbits to generate anti‐AD7C‐NTP antibodies. The urine AD7C‐NTP ELISA kit was then established; the generated mouse anti‐AD7C‐NTP antibody was used as a capture antibody, the biotin‐labeled rabbit anti‐AD7C‐NTP antibody was used as a detection antibody, and avidin labeled by horseradish peroxidase was used as a substrate. The first morning urine specimens of 121 AD patients and 118 age‐matched controls were collected, and the urine AD7C‐NTP levels were detected by the above ELISA kit.

Results

Mouse and rabbit anti‐AD7C‐NTP antibody ELISA titer was found to be 1:8,000 and 1:32,000, respectively. A single band with a relative molecular mass of 41 kDa was found in human brain specimens by Western blot assay, which was identified as AD7C‐NTP antibody. The urine AD7C‐NTP concentration of the AD patients was higher than that of the age‐matched controls, the sensitivity was 89.3% and the specificity was 84.7%.

Conclusions

Our study demonstrated that our newly developed urine AD7C‐NTP ELISA kit has suggested potential for diagnosing AD in a Chinese population, suggesting it may be a useful diagnostic kit for detecting early AD.
Evaluation of disease‐mediated therapeutic protein–drug interactions between an anti–interleukin‐6 monoclonal antibody (sirukumab) and cytochrome P450 activities in a phase 1 study in patients with rheumatoid arthritis using a cocktail approach
Authors: Zhuang Yanli , de Vries Dick E. , Xu Zhenhua , Marciniak Stanley J. , Chen Dion , Leon Francisco , Davis Hugh M. , Zhou Honghui
Published: June 2015

This therapeutic protein–drug interaction study evaluated the disease‐mediated effect of sirukumab (anti‐interleukin 6 [anti‐IL‐6] monoclonal antibody) on the pharmacokinetics of the cytochrome P450 (CYP) probe substrates midazolam (CYP3A), omeprazole (CYP2C19), warfarin (CYP2C9), and caffeine (CYP1A2) in patients with active rheumatoid arthritis (RA). Twelve patients with C‐reactive protein (CRP) ≥ 8.0 mg/L at screening received oral administration of a CYP probe cocktail consisting of 0.03 mg/kg midazolam, 10 mg warfarin + 10 mg vitamin K (equivalent to 5 mg S‐warfarin), 20 mg omeprazole, and 100 mg caffeine 1 week before and 1, 3, and 6 weeks after a single subcutaneous dose of 300 mg sirukumab. The results showed that the pharmacokinetics of midazolam, omeprazole, and S‐warfarin were nonequivalent before and after the administration of a single dose of 300 mg sirukumab. Area under the plasma concentration–time curve (AUC0–∞) for midazolam, omeprazole, and S‐warfarin was reduced by 30%−35%, 37%−45%, and 18%−19%, respectively, after sirukumab administration. Caffeine AUC0–∞ was increased by 20%−34% after sirukumab administration. The effect of sirukumab on CYP substrates was sustained for at least 6 weeks. No new adverse drug reactions related to the administration of sirukumab were observed in this study. These results suggest that sirukumab may reverse IL‐6‐mediated suppression of CYP3A, CYP2C9, and CYP2C19 activities in patients with active RA.
Defect pyrochlore oxides: as photocatalyst materials for environmental and energy applications ‐ a review
Authors: Jitta Raju Reddy , Gundeboina Ravi , Veldurthi Naveen Kumar , Guje Ravinder , Muga Vithal
Published: June 2015

Photocatalytic technology utilizing abundant solar light holds great promise to tackle many challenging environmental and energy issues. In recent years, various types of photocatalysts have been developed that are active for environmental purification and hydrogen production. Papers reporting preparation, characterization and photocatalytic testing of binary, ternary and quaternary compounds have been reviewed. The present review focuses on photocatalyst materials which adopt a defect pyrochlore structure. Starting with a brief introduction to semiconductor‐based photocatalysts for environmental clean‐up and hydrogen generation from water splitting, the development of high‐efficiency UV and visible light driven photocatalysts belonging to the defect pyrochlore family is reviewed. The review covers all the defect pyrochlore photocatalysts studied so far, and provides guidance to researchers in this area for further investigation of these materials. © 2015 Society of Chemical Industry
Synthesis and Chemical Reactivity of a 6‐Me‐3,2‐Hydroxypyridinone Dithiazolide with Primary Amines: A route to New Hexadentate Chelators for Hard Metal(III) Ions
Authors: Pailloux Sylvie L. , Nguyen Sean , Zhou Stephanie , Hom Marisa E. , Keyser Michelle N. , Smiles Danil , Raymond Kenneth N.
Published: June 2015

A hydroxypyridinone building block, bifunctionalized with thiazoline, has been prepared from orthogonally protected 2‐(3‐(benzyloxy)‐4‐(ethoxycarbonyl)‐6‐methyl‐2‐oxopyridin‐1(2H)‐yl) acetic acid. The reactivity of the dithiazolide has been explored with two primary amines, leading to the synthesis and characterization of four new hexadentate ligands. Their complexes with selected hard trivalent ions pertinent to potential molecular imaging applications have been surveyed.
A Practical and Scalable Synthesis of GTx‐134, an IGF‐1R Inhibitor
Authors: Liu Yahu A. , Gregor Vlad E.
Published: June 2015

A practical and scalable synthesis of GTx‐134, a novel small‐molecule inhibitor of insulin‐like growth factor 1 receptor showing antitumor activity in preclinical models of multiple myeloma, is reported.
Oncologic outcome after local recurrence of chondrosarcoma: Analysis of prognostic factors
Authors: Kim Han‐Soo , Bindiganavile Srimanth S. , Han Ilkyu
Published: June 2015

Background

Literature on outcome after local recurrence (LR) in chondrosarcoma is scarce and better appreciation of prognostic factors is needed.

Objectives

(1) To evaluate post‐LR oncologic outcomes of disease‐specific survival and subsequent LR and (2) to identify prognostic factors for post‐LR oncologic outcomes.

Patients and Methods

Review of 28 patients with locally recurrent chondrosarcoma from the original cohort of 150 patients, who were treated surgically with or without adjuvants between 1982 and 2011, was performed. Mean age was 46 years (range, 21–73) which included 20 males and 8 females with mean follow up of 8.4 ± 7.5 years (range, 1.2–31.0).

Results

Post‐LR survival at 5 years was 58.6 ± 10.3%. Age greater than 50 years (P = 0.011) and LR occurring within 1 year of primary surgery (P = 0.011) independently predicted poor survival. Seven patients suffered subsequent LR, which was significantly affected by surgical margin for LR (P = 0.038).

Conclusion

Long‐term survival of locally recurrent chondrosarcoma is achievable in a substantial number of patients. Older age at onset of LR and shorter interval from primary surgery to LR identifies high risk patients for poor post‐LR survival while, wide surgical margins at LR surgery reduces the risk of subsequent LR. J. Surg. Oncol. 2015 111:957–961. © 2015 Wiley Periodicals, Inc.
Prognostic factors and follow‐up strategy for superficial soft‐tissue sarcomas: Analysis of 622 surgically treated patients from the scandinavian sarcoma group register
Authors: Tsagozis Panagiotis , Bauer Henrik C. , Styring Emelie , Trovik Clement S. , Zaikova Olga , Brosjö Otte
Published: June 2015

Background and Objectives

Our study aimed to describe the clinical outcome of patients with superficial soft‐tissue sarcomas (SSTS), define prognostic factors and provide evidence for a rational surveillance scheme.

Methods

Data for 622 consecutive, surgically treated SSTS patients were retrieved from the Scandinavian Sarcoma Group Register. We assessed the rates of local recurrence (LR) and metastasis (M), as well as overall survival (OS), local recurrence free‐survival (LRFS) and metastasis‐free survival (MFS) of the cohort.

Results

The incidence of LR and M was 9% and 12%, respectively. OS at 5 years was 79%, LRFS was 74% and MFS 76%. Factors that affected OS, LRFS, and MFS were tumor size and patient age. Additionally, tumor grade was an independent prognostic factor for LRFS. The majority of LR and M events were observed the first 2 years of follow‐up. Clear surgical margins were correlated to lower risk for LR. Selected patients benefited from adjuvant radiotherapy.

Conclusions

SSTS have a favourable prognosis, which is mainly determined by tumour‐associated factors. Adequate surgical margins are important for local control, whereas radiotherapy has a secondary role. The data support current surveillance schemes, with a closer follow‐up the first 2 years after surgery. J. Surg. Oncol. 2015 111:951–956. © 2015 Wiley Periodicals, Inc.
Multi‐temporal Forest Cover Change and Forest Density Trend Detection in a Mediterranean Environment
Authors: Symeonakis Elias , Caccetta Peter A. , Wallace Jeremy F. , Arnau‐Rosalen Eva , Calvo‐Cases Adolfo , Koukoulas Sotirios
Published: June 2015

The loss of forests along with the various types of shrubs in the Mediterranean region is seen as an important driver of climate change and has been repeatedly related with the observed land degradation and desertification in the region. Nevertheless, the extent of woody perennial vegetation cover (WPVC) and its density remain largely unclear. Here, we apply a series of algorithms and methods operationally used in Australia for large‐scale WPVC mapping and monitoring and demonstrate their applicability in the Mediterranean region using a Spanish area as the trial site. Five Landsat TM and ETM+ images from various dates spanning 14 years are used to map changes in the extent of WPVC and to identify areas with a declining, stabilising or recovering trend. Results show that the applied methodology, which incorporates (i) pre‐processing of the Landsat imagery, (ii) a canonical variate analysis to spectrally discriminate between woody and non‐woody land cover types, (iii) a conditional probability network and (iv) spectral indices for mapping woody cover and density trend, is highly successful and well suited for use in Mediterranean environments. A rigorous accuracy assessment is undertaken producing overall accuracies above 97% for both woody and non‐woody cover types and all dates. Results also show that in the area of study, the majority of WPVC disturbances were due to forest fires, which represent the region's most frequent natural and anthropogenic disturbance. This raises significant concerns about the future of the area's WPVC. Regeneration compensated to some degree for the high disturbance rates. Copyright © 2015 John Wiley & Sons, Ltd.
On the Cauchy problem for Wigner–Poisson–BGK equation in the Wiener algebra
Authors: Li Bin , Shen Jieqiong
Published: June 2015

In this paper, we prove the existence and uniqueness of the local mild solution to the Cauchy problem of the n‐dimensional (n≥3) Wigner–Poisson–BGK equation in the space of some integrable functions whose inverse Fourier transform are integrable. The main difficulties in establishing mild solution are to derive the boundedness and locally Lipschitz properties of the appropriate nonlinear terms in the Wiener algebra. Copyright © 2015 John Wiley & Sons, Ltd.
Global properties of a discrete viral infection model with general incidence rate
Authors: Hattaf Khalid , Yousfi Noura
Published: June 2015

In this paper, we propose a discrete viral infection model with a general incidence rate. The discrete model is derived from a continuous case by using a 'mixed' Euler method, which is a mixture of both forward and backward Euler methods. We prove that the mixed Euler method preserves the qualitative properties of the corresponding continuous system, such as positivity, boundedness, and global behaviors of solutions. Furthermore, the model and mathematical results presented in another previous study are extended and generalized. Copyright © 2015 John Wiley & Sons, Ltd.
Mit Sonnenlicht zum Wasserstoff
Authors: Marschall Roland
Published: June 2015

Die Wirkungsgrade von Halbleiteroxiden für die heterogene photokatalytische Wasserspaltung sind oft noch sehr niedrig. Neue Ansätze der Materialforschung sollen dieses Problem lösen.
Development of a discontinuous approach for modeling fluid flow in heterogeneous media using the numerical manifold method
Authors: Hu Mengsu , Wang Yuan , Rutqvist Jonny
Published: June 2015

In the numerical modeling of fluid flow in heterogeneous geological media, large material contrasts associated with complexly intersected material interfaces are challenging, not only related to mesh discretization but also for the accurate realization of the corresponding boundary constraints. To address these challenges, we developed a discontinuous approach for modeling fluid flow in heterogeneous media using the numerical manifold method (NMM) and the Lagrange multiplier method (LMM) for modeling boundary constraints. The advantages of NMM include meshing efficiency with fixed mathematical grids (covers), the convenience of increasing the approximation precision, and the high integration precision provided by simplex integration. In this discontinuous approach, the elements intersected by material interfaces are divided into different elements and linked together using the LMM. We derive and compare different forms of LMMs and arrive at a new LMM that is efficient in terms of not requiring additional Lagrange multiplier topology, yet stringently derived by physical principles, and accurate in numerical performance. To demonstrate the accuracy and efficiency of the NMM with the developed LMM for boundary constraints, we simulate a number of verification and demonstration examples, involving a Dirichlet boundary condition and dense and intersected material interfaces. Last, we applied the developed model for modeling fluid flow in heterogeneous media with several material zones containing a fault and an opening. We show that the developed discontinuous approach is very suitable for modeling fluid flow in strongly heterogeneous media with good accuracy for large material contrasts, complex Dirichlet boundary conditions, or complexly intersected material interfaces. Copyright © 2015 John Wiley & Sons, Ltd.
A stability criterion for elasto‐viscoplastic constitutive relationships
Authors: Pisanò F. , Prisco C. di
Published: June 2015

In this paper, the onset of mechanical instability in time‐sensitive elasto‐viscoplastic solids is theoretically analyzed at the constitutive level and associated with the occurrence of ‘spontaneous accelerations’ under stationary external perturbations. For this purpose, a second‐order form of Perzyna's constitutive equations is first derived by time differentiation, and a sufficient stability condition is identified for general mixed loading programs. These loading conditions are in fact the most general in both laboratory tests and real boundary value problems, where a combination of certain stress and strain components is known/prescribed.

The theoretical analysis leads to find precise stability limits in terms of material hardening modulus. In the case of constitutive relationships with isotropic strain‐hardening, no instabilities are possible while the hardening modulus is larger than the so‐called ‘controllability modulus’ defined for (inviscid) elasto‐plastic materials. It is also shown that the current stress/strain rate may also directly influence the occurrence of elasto‐viscoplastic instability, which is at variance with elasto‐plastic inviscid media. Copyright © 2015 John Wiley & Sons, Ltd.
3D finite element modeling of sand particle fracture based on in situ X‐Ray synchrotron imaging
Authors: Druckrey Andrew M. , Alshibli Khalid A.
Published: June 2015

Compressive loading of granular materials causes inter‐particle forces to develop and evolve into force chains that propagate through the granular body. At high‐applied compressive stresses, inter‐particle forces will be large enough to cause particle fracture, affecting the constitutive behavior of granular materials. The first step to modeling particle fracture within force chains in granular mass is to understand and model the fracture of a single particle using actual three‐dimensional (3D) particle shape. In this paper, the fracture mode of individual silica sand particles was captured using 3D x‐ray radiography and Synchrotron Micro‐computed Tomography (SMT) during in situ compression experiments. The SMT images were used to reconstruct particle surfaces through image processing techniques. Particle surface was then imported into Abaqus finite element (FE) software where the experimental loading setup was modeled using the extended finite element method (XFEM) where particle fracture was compared to experimental fracture mode viewed in radiograph images that were acquired during experimental loading. Load‐displacement relationships of the FE analysis were also compared with experimental measurements. 3D FE modeling of particle fracture offers an excellent tool to map stress distribution and monitors crack initiation and propagation within individual sand particles. Copyright © 2015 John Wiley & Sons, Ltd.
Occupational Deprivation or Occupational Adaptation of Mexican Americans on Renal Dialysis
Authors: Wells Shirley A.
Published: June 2015

The aim of this study was to explore the occupational changes and perceptions experienced by Mexican Americans with end‐stage renal disease (ESRD) and their families living with dialysis. In‐depth interviews were conducted with 17 Mexican Americans with ESRD and 17 family members. The participants with ESRD described altered or lost activity patterns, capacities and freedoms. With a heightened awareness of death, the family members made altered occupational choices, which were consistent with their cultural values. Changes in the physical body, adhering to the dialysis regimen and environmental restrictions created barriers to occupational participation. These findings suggest that living with dialysis facilitate occupational deprivation among individuals with ESRD and adaption among the family members within cultural alignments. This phenomenon could affect the design of occupational therapy intervention and call for research on the role of occupation therapy services with this population. Copyright © 2015 John Wiley & Sons, Ltd.
Preparation, health benefits and applications of resistant starch—a review
Authors: Ashwar Bilal Ahmad , Gani Adil , Shah Asima , Wani Idrees Ahmed , Masoodi Farooq Ahmad
Published: June 2015

Resistant starch (RS) encompasses those forms of starch, which are not accessible to human digestive enzymes and are fermented in the colon producing short chain fatty acids. Because of its unique physicochemical and functional properties resistant starch finds use in wide range of food products and yields high quality products. It has recently gained substantial importance due to its positive impact on health. Among the health benefits include improvement of colonic health and microflora, management of diabetes, lower glycemic index and blood cholesterol levels, reduced bilestone formation, increased mineral absorption, and potential to modify fat oxidation. Technically RS can be produced by different physical, enzymatic and chemical modifications. This article reviews about types of resistant starch, sources, preparation, health benefits, and applications of resistant starch.
Efficient performance‐based design using parallel and cloud computing
Authors: Ventura Carlos E. , Bebamzadeh Armin , Fairhurst Michael
Published: June 2015

Performance‐based design offers a more direct, non‐prescriptive and rational approach over more traditional approaches used for the design of buildings and other structures. However, performance‐based design requires the use of extensive nonlinear analyses on three‐dimensional building models and typically requires significant computational capabilities and/or time to conduct such analyses. A practical way to overcome these limitations is to utilize recent advantages in parallel computing using cloud‐based servers to conduct the necessary analyses. This approach can be used as a cost‐effective way to conduct structural analyses in a fraction of the time compared with traditional computational methods. This paper explores the use of parallel and cloud computing in the performance‐based design and analysis of tall buildings. Two case studies are presented that highlight the application of high‐performance computing for the nonlinear dynamic analysis of a detailed 52‐story building model. These case studies highlight both the cost and time benefits provided by high‐performance computing for performance‐based earthquake engineering. Copyright © 2015 John Wiley & Sons, Ltd.
Facilitating Meaningful Discussion Groups in the Primary Grades
Authors: Moses Lindsey , Ogden Meridith , Beth Kelly Laura
Published: June 2015

This Teaching Tips describes a yearlong process of facilitating meaningful discussion groups about literature with first‐grade students in an urban Title I school. At the beginning of the year, the teacher provided explicit instruction in speaking and listening skills to support students with the social skills needed for thoughtful discussion. She established whole‐group discussions as a forum for sharing thinking and new knowledge, engaging in dialog about books, and recommending books to friends. Building on this foundation, the class moved to small‐group discussions. The article details three different types of discussion groups: informational texts and sharing learning; Mo Willems author study and sharing responses to humor; and Jon Klassen author study and sharing inferences supported by textual evidence. This article shares how first grade students took up discussion opportunities to engage in critical thinking and dialog about books.
An energy‐efficient asynchronous wake‐up scheme for underwater acoustic sensor networks
Authors: Su Ruoyu , Venkatesan Ramachandran , Li Cheng
Published: June 2015

In addition to the requirements of the terrestrial sensor network where performance metrics such as throughput and packet delivery delay are often emphasized, energy efficiency becomes an even more significant and challenging issue in underwater acoustic sensor networks, especially when long‐term deployment is required. In this paper, we tackle the problem of energy conservation in underwater acoustic sensor networks for long‐term marine monitoring applications. We propose an asynchronous wake‐up scheme based on combinatorial designs to minimize the working duty cycle of sensor nodes. We prove that network connectivity can be properly maintained using such a design even with a reduced duty cycle. We study the utilization ratio of the sink node and the scalability of the network using multiple sink nodes. Simulation results show that the proposed asynchronous wake‐up scheme can effectively reduce the energy consumption for idle listening and can outperform other cyclic difference set‐based wake‐up schemes. More significantly, high performance is achieved without sacrificing network connectivity. Copyright © 2015 John Wiley & Sons, Ltd.
The first description of population density and habitat use of the mainland clouded leopard Neofelis nebulosa within a logged‐primary forest in South East Asia
Authors: Mohamad Shariff Wan , Rayan D. Mark , Christopher Wong Chai Thiam , Hamirul Muhamad , Mohamed Azlan , Lau Ching Fong , Siwan Elangkumaran Sagtia
Published: June 2015

The mainland clouded leopard (Neofelis nebulosa) is classified as vulnerable under the IUCN Red List, meaning that it faces a high risk of extinction in the wild. However, hardly any ecological research has been published on this species apart from several radiotelemetry studies in Thailand and Nepal, and one camera‐trapping study in India. Here we present findings on the clouded leopard from a camera‐trapping study conducted in Temengor forest reserve (a logged‐over forest) and Royal Belum State Park (a primary forest) within Peninsular Malaysia. Using the spatially‐explicit capture‐recapture method, the density from Temengor forest reserve and Royal Belum State Park was estimated at 3.46 ± SE 1.00 and 1.83 ± SE 0.61, respectively. Clouded leopard habitat use was found to be highly influenced by the availability of small and medium prey species and therefore intrinsically highlights the potential conservation importance of species such as pig‐tailed macaques, porcupine, mouse deer and small carnivores. These findings provide the first estimates of density and habitat use of this species in a logged‐primary forest from both Peninsular Malaysia and South East Asia. Our study provides important baseline information on clouded leopards and contributes to filling up the knowledge gap that exists in understanding the population ecology of this species, not only within Peninsular Malaysia, but also on a regional level.
Computed Tomography's Influence on the Classifications and Treatment of the Distal Radius Fractures
Authors: Nascimento Valdênia das Graças , da Costa Antonio Carlos , Falcochio Diego Figueira , Lanzarin Leonardo Depiere , Checchia Sérgio Luiz , Chakkour Ivan
Published: June 2015

Introduction

Distal radius fractures are common in emergency centers. The radiographic routine includes at least two radiographic projections used for diagnosing most of these fractures. Computed tomography (CT) is indicated for evaluating complex fractures that affect the articular surface, as well as the fragments' size and position. There are not enough comparative studies on choosing classification and treatment by means of the four radiographic projections and computed tomography (CT) and the association of these with the levels of expertise.

Methods

We conducted a randomized cross-sectional study by observing images from 61 patients with distal radius fractures organized in two phases: the first phase comprising radiographic images alone and the second one with those same images associated with tomograms. Seventeen evaluators with different levels of training and expertise classified the fractures according to the AO and Universal classification systems and proposed treatment guidelines.

Results

The agreement between the AO and Universal classification ratings was poor (worse for the former), with smaller Fleiss' kappa resulting from data obtained by orthopedics residents and non-specialist orthopedists. CT influenced the classification choice, with a higher change frequency for more complex patterns in the AO classification system and intra-articular and irreducible fractures in the Universal classification system, especially in the group comprised of orthopedic residents and orthopedic physicians. CT did not influence the treatment choice made by the group comprised of hand surgery residents and hand surgeons.

Conclusion

The less experienced in hand surgery the observer was, the more important computed tomography was for determining the fracture pattern.
Salt‐Induced Modulation of the Krafft Temperature and Critical Micelle Concentration of Benzyldimethylhexadecylammonium Chloride
Authors: nazrul Islam Md. , Sharker Komol Kanta , Sarker Khokan Chandra
Published: June 2015

In this work, the effect of some sodium salts on the Krafft temperature (TK) and critical micelle concentration (CMC) of benzyldimethylhexadecylammonium chloride (C16Cl) in aqueous solution has been studied. It was observed that the TK can be modulated to lower and higher values and the CMC can be depressed significantly upon the addition of the electrolytes. More chaotropic Br− and I− raise the TK with an increase of the concentration of the ions. On the other hand, less chaotropic NO3− initially lowers and then raises the TK. Kosmotropic F−, SO42− and CO32− gradually lower the TK with increasing concentration of the electrolytes. The more chaotropic ions form contact ion pairs with the surfactant and decrease the solubility with a consequent increase in the TK. On the other hand, kosmotropic ions, being extensively hydrated in the bulk, remain separated from the surfactant by hydrated layers of water molecules. As a result, a significant electrostatic repulsion exists between the charged headgroups of the surfactant, resulting in a decrease in the TK. The CMC of the surfactant decreases significantly in the presence of these ions. The surface tension at the CMC (γCMC) also decreases in the presence of all the salts except for F−. The electrostatic repulsion between the charged headgroups is significantly reduced because of screening of the surface charge of both micelles and adsorbed monolayers by the associated counterions, resulting in a decrease in both the CMC and γCMC.
Giant intracardiac blood cyst: assessing the relationship between its formation and previous cardiac surgery
Authors: Halim J. , van Schaagen F.R.N. , Riezebos R.K. , Lalezari S.
Published: June 2015

This case report discusses a 23-year-old male patient who presented with shortness of breath during exercise. Echocardiography revealed an intracardiac mass located on the mitral valve. His medical history included surgical closure of an atrial septal defect type 2 at the age of 2 years. After being discussed within a multidisciplinary heart team, the intracardiac mass was surgically removed. Histopathological examination revealed a blood cyst. This case report emphasises that the presence of an acquired intracardiac cyst is a rare entity and that a pathophysiological association between the formation of a blood cyst and previous cardiac surgery has not been proven yet.
GEOMETRISATION OF FIRST-ORDER LOGIC
Authors: DYCKHOFF ROY , NEGRI SARA
Published: June 2015

That every first-order theory has a coherent conservative extension is regarded by some as obvious, even trivial, and by others as not at all obvious, but instead remarkable and valuable; the result is in any case neither sufficiently well-known nor easily found in the literature. Various approaches to the result are presented and discussed in detail, including one inspired by a problem in the proof theory of intermediate logics that led us to the proof of the present paper. It can be seen as a modification of Skolem’s argument from 1920 for his “Normal Form” theorem. “Geometric” being the infinitary version of “coherent”, it is further shown that every infinitary first-order theory, suitably restricted, has a geometric conservative extension, hence the title. The results are applied to simplify methods used in reasoning in and about modal and intermediate logics. We include also a new algorithm to generate special coherent implications from an axiom, designed to preserve the structure of formulae with relatively little use of normal forms.
Recurrence pattern of surgically-resected skull base versus superficial meningiomas, signs of divergent pattern
Authors: Taslimi S , Klironomos G , Mansouri A , kilian A , Gentili F , Zadeh G
Published: June 2015

Background: To identify differences in the recurrence pattern of surgically-resected skull base meningiomas compared with superficial intra-cranial meningiomas Methods: A retrospective hospital-based study of all patients referred to our institution from 1990 to 2014 for surgical resection of meningiomas was conducted (both primary and recurrent cases). Survival analysis was performed using IBM SPSS v22.0. Results: Overal, 398 intra-cranial meningiomas –129 (32%) skull base - were reviewed. Skull base tumors had a lower MIB-1 index (p = 0.001) and were more likely to be WHO I (p = 0.003). Meningiomas in all locations demonstrated a recurrence rate of 30% at 100 months of follow-up. Afterwards, the recurrence of skull base meningiomas plateaued (longest follow-up: 250 months) whereas superficial lesions had a recurrence rate of 80% at 230 months (p = 0.02). In multivariable analysis, patients with a first-time diagnosis (p = 0.02), those with WHO I or II tumors (p= 0.02 and 0.05), and those with a total resection (p < 0.01) were less likely to experience a recurrence. Conclusions: Skull base meningiomas are less aggressive than superficial lesions and may not need to be followed beyond 100 months. The WHO grade, complete resection, and prior recurrence are predictive factors of recurrence.
Surgical and seizure outcome in children with DNETs who underwent epilepsy surgery
Authors: Bueckert AM , Pugh J , Snyder T , Wheatley M , Jacob F , Sinclair B
Published: June 2015

Background: Dysembryoblastic neuroepithelial tumors (DNETs) are benign tumors of the cerebral cortex that most commonly occur in children or young adults. Seizures are a frequent presenting feature, with an incidence of 80-100%, and are often an indication for surgical resection. Methods: We performed a retrospective chart review of children with DNETs who underwent epilepsy surgery between 1998 and 2014. Results: A total of 12 subjects were identified (6 males, 6 females), all of whom had seizures prior to surgical resection. Of these patients, 1 had infantile spasms, 2 had simple partial seizures and 10 had complex partial seizures. Tumors were located in the temporal (n=7), frontal (n=3) or parietal (n=2) cortex. These patients went on to have surgery on average 15 months after seizure onset, 3 had incomplete resections. At an average follow up of 6 years 4 months, all patients were class 1 on Engel’s Classification. All but one subject with rare non-disabling seizures were seizure free, with only 6 on medication. Follow up MR imaging revealed tumor recurrence in 1 subject. Conclusions: Despite differing seizure seminology and tumor location, surgical resection of these low-grade tumors resulted in excellent seizure outcome even in the setting of incomplete tumor resection.
Utilization of transition care management plans to facilitate transition of adolescents with epilepsy into the adult healthcare system
Authors: Hrazdil C , Datta A , Michoulas A , Morgan S , Peinhof S , Selby K , Straatman L , Rabinovitz S , Chapman A , Evans D , Lachar J , Paone M , Sayao A , Whitehouse S , Woodfield W , Connolly M
Published: June 2015

Background: For adolescents with epilepsy, there is often a poor system in place to meet their individualized transition needs. Our objectives were 1) to develop epilepsy-specific transition care management plans (TCMPs) to ensure access, and attachment to adult healthcare providers, and 2) to identify strategies for providing support during the transition period, including through the development of physician and patient (or caregiver) navigated web-based tools, resources and recommendations for health system improvements. Methods: Physicians and nurses with expertise in areas including adult and pediatric epilepsy, family medicine, psychiatry, and varied allied health professionals were engaged to generate epilepsy-related TCMPs. Results: Through an iterative process spanning the course of over a year, TCMPs were developed to cover areas including: treatment responsive and resistant epilepsy, ketogenic diet, epilepsy surgery, women’s issues, mental health, and psychosocial aspects of epilepsy. The TCMPs referenced established guidelines and best practices in the literature wherever possible. Caregiver roles and responsibilities were outlined, remaining cognoscent of available provincial resources. Conclusions: Epilepsy specific TCMPs can be developed through a collaborative approach between pediatric and adult healthcare providers, easing the patient experience, creating educated accountability, and providing a forum to identify and address gaps of care in adolescents with epilepsy.