bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliable change in neuropsychological assessment of breast cancer survivors
Authors: Andreotti Charissa , Root James C. , Schagen Sanne B. , McDonald Brenna C. , Saykin Andrew J. , Atkinson Thomas M. , Li Yuelin , Ahles Tim A.
Published: March 2015

Background

The purpose of this study was to enhance the current understanding and interpretation of longitudinal change on tests of neurocognitive function in individuals with cancer. Scores on standard neuropsychological instruments may be impacted by practice effects and other random forms of error.

Methods

The current study assessed the test–retest reliability of several tests and overarching cognitive domains comprising a neurocognitive battery typical of those used for research and clinical evaluation using relevant time frames. Practice effect‐adjusted reliable change confidence intervals for test–retest difference scores based on a sample of patient‐matched healthy controls are provided.

Results

By applying reliable change confidence intervals to scores from two samples of breast cancer patients at post‐treatment follow‐up assessment, meaningful levels of detectable change in cognitive functioning in breast cancer survivors were ascertained and indicate that standardized neuropsychological instruments may be subject to limitations in detection of subtle cognitive dysfunction over clinically relevant intervals, especially in patient samples with average to above average range baseline functioning.

Conclusions

These results are discussed in relation to reported prevalence of cognitive change in breast cancer patients along with recommendations for study designs that enhance detection of treatment effects. Copyright © 2015 John Wiley & Sons, Ltd.
Observing a Catastrophic Thermokarst Lake Drainage in Northern Alaska
Authors: Jones Benjamin M. , Arp Christopher D.
Published: March 2015

The formation and drainage of thermokarst lakes have reshaped ice‐rich permafrost lowlands in the Arctic throughout the Holocene. North of Teshekpuk Lake, on the Arctic Coastal Plain of northern Alaska, thermokarst lakes presently occupy 22.5% of the landscape, and drained thermokarst lake basins occupy 61.8%. Analysis of remotely sensed imagery indicates that nine lakes (>10 ha) have drained in the 1,750 km2 study area between 1955 and 2014. The most recent lake drainage was observed using in situ data loggers providing information on the duration and magnitude of the event, and a nearby weather station provided information on the environmental conditions preceding the lake drainage. Lake 195 (L195), an 80 ha thermokarst lake with an estimated water volume of ~872,000 m3, catastrophically drained on 05 July 2014. Abundant winter snowfall and heavy early summer precipitation resulted in elevated lake water levels that likely promoted bank overtopping, thermo‐erosion along an ice‐wedge network, and formation of a 9 m wide, 2 m deep, and 70 m long drainage gully. The lake emptied in 36 hours, with 75% of the water volume loss occurring in the first ten hours. The observed peak discharge of the resultant flood was 25 m3/s, which is similar to that in northern Alaska river basins whose areas are more than two orders of magnitude larger. Our findings support the catastrophic nature of sudden lake drainage events and the mechanistic hypotheses developed by J. Ross Mackay. Copyright © 2015 John Wiley & Sons, Ltd.
Arginine: Its pKa value revisited
Authors: Fitch Carolyn A. , Platzer Gerald , Okon Mark , Garcia‐Moreno E. Bertrand , McIntosh Lawrence P.
Published: March 2015

Using complementary approaches of potentiometry and NMR spectroscopy, we have determined that the equilibrium acid dissociation constant (pKa value) of the arginine guanidinium group is 13.8 ± 0.1. This is substantially higher than that of ∼12 often used in structure‐based electrostatics calculations and cited in biochemistry textbooks. The revised intrinsic pKa value helps explains why arginine side chains in proteins are always predominantly charged, even at pH values as great as 10. The high pKa value also reinforces the observation that arginine side chains are invariably protonated under physiological conditions of near neutral pH. This occurs even when the guanidinium moiety is buried in a hydrophobic micro‐environment, such as that inside a protein or a lipid membrane, thought to be incompatible with the presence of a charged group.
Managing the evolution of herbicide resistance
Authors: Evans Jeffrey A , Tranel Patrick J , Hager Aaron G , Schutte Brian , Wu Chenxi , Chatham Laura A , Davis Adam S
Published: March 2015

BACKGROUND

Understanding and managing the evolutionary responses of pests and pathogens to control efforts is essential to human health and survival. Herbicide‐resistant (HR) weeds undermine agricultural sustainability, productivity and profitability, yet the epidemiology of resistance evolution – particularly at landscape scales – is poorly understood. We studied glyphosate resistance in a major agricultural weed, Amaranthus tuberculatus (common waterhemp), using landscape, weed and management data from 105 central Illinois grain farms, including over 500 site‐years of herbicide application records.

RESULTS

Glyphosate‐resistant (GR) A. tuberculatus occurrence was greatest in fields with frequent glyphosate applications, high annual rates of herbicide mechanism of action (MOA) turnover and few MOAs field−1 year−1. Combining herbicide MOAs at the time of application by herbicide mixing reduced the likelihood of GR A. tuberculatus.

CONCLUSIONS

These findings illustrate the importance of examining large‐scale evolutionary processes at relevant spatial scales. Although measures such as herbicide mixing may delay GR or other HR weed traits, they are unlikely to prevent them. Long‐term weed management will require truly diversified management practices that minimize selection for herbicide resistance traits. © 2015 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Total chemical synthesis of human interferon alpha‐2b via native chemical ligation
Authors: Li Jing , Lehmann Clara , Chen Xishan , Romerio Fabio , Lu Wuyuan
Published: March 2015

Interferon‐alpha (IFNα) is a cytokine that orchestrates innate and adaptive immune responses and potently inhibits proliferation of normal and tumor cells. These properties have warranted the use of IFNα in clinical practice for the treatment of several viral infections and malignancies. However, overexpression of IFNα leads to immunopathology observed in the context of chronic viral infections and autoimmune conditions. Thus, it is desirable to develop therapeutic approaches that aim at suppressing excessive IFNα production. To that end, artificial evolution of peptides from phage display libraries represents a strategy that seeks to disrupt the interaction between IFNα and its cell surface receptor and thus inhibit the ensuing biological effects. Mirror‐image phage display that screens peptide libraries against the D‐enantiomer is particularly attractive because it allows for identification of proteolysis‐resistant D‐peptide inhibitors. This approach, however, relies on the availability of chemically synthesized D‐IFNα composed entirely of D‐amino acids. Here, we describe the synthesis and biological properties of IFNα2b of 165 amino acid residues produced by native chemical ligation, which represents an important first step toward the discovery of D‐peptide antagonists with potential therapeutic applications. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.
Development of a multi‐parameter sensor chip for the simultaneous detection of organic compounds in biogas processes
Authors: Pilas Johanna , Iken Heiko , Selmer Thorsten , Keusgen Michael , Schöning Michael J.
Published: March 2015

An enzyme‐based multi‐parameter biosensor is developed for monitoring the concentration of formate, d‐lactate, and l‐lactate in biological samples. The sensor is based on the specific dehydrogenation by an oxidized β‐nicotinamide adenine dinucleotide (NAD+)‐dependent dehydrogenase (formate dehydrogenase, d‐lactic dehydrogenase, and l‐lactic dehydrogenase, respectively) in combination with a diaphorase from Clostridium kluyveri (EC 1.8.1.4). The enzymes are immobilized on a platinum working electrode by cross‐linking with glutaraldehyde (GA). The principle of the determination scheme in case of l‐lactate is as follows: l‐lactic dehydrogenase (l‐LDH) converts l‐lactate into pyruvate by reaction with NAD+. In the presence of hexacyanoferrate(III), the resulting reduced β‐nicotinamide adenine dinucleotide (NADH) is then regenerated enzymatically by diaphorase. The electrochemical detection is based on the current generated by oxidation of hexacyanoferrate(II) at an applied potential of +0.3 V vs. an Ag/AgCl reference electrode. The biosensor will be electrochemically characterized in terms of linear working range and sensitivity. Additionally, the successful practical application of the sensor is demonstrated in an extract from maize silage.
Light‐controllable polymeric material based on temperature‐sensitive hydrogels with incorporated graphene oxide
Authors: Breuer L. , Raue M. , Kirschbaum M. , Mang T. , Schöning M. J. , Thoelen R. , Wagner T.
Published: March 2015

Poly(N‐isopropylacrylamide) (PNIPAAm) hydrogel films with incorporated graphene oxide (GO) were developed and tested as light‐stimulated actuators. GO dispersions were synthesized via Hummers method and characterized toward their optical properties and photothermal energy conversion. The hydrogels were prepared by means of photopolymerization. In addition, the influence of GO within the hydrogel network on the lower critical solution temperature (LCST) was investigated by differential scanning calorimetry (DSC). The optical absorbance and the response to illumination were determined as a function of GO concentration for thin hydrogel films. A proof of principle for the stimulation with light was performed.
Hydrostatic pressure, temperature and aluminum concentration effects on the ground state of coupled donors in a GaAs–Ga1−xAlxAs quantum well
Authors: Fulla M. R. , Suaza Y. A. , Marín J. H.
Published: March 2015

The combined effects of hydrostatic pressure, temperature, and aluminum concentration on the binding and total energies of two coupled donors are analyzed using a variational procedure. The effects of changing the nucleus–nucleus relative positions and the quantum well size on the complex binding energy were also analyzed. The results show that an increase in the temperature yields a decrease of the binding energy while an increase in the aluminum concentration or hydrostatic pressure, enhance the binding energy favoring the stability of molecular complex under strong quantum confinement conditions.
Experimental designs for detecting synergy and antagonism between two drugs in a pre‐clinical study
Authors: Sperrin Matthew , Thygesen Helene , Su Ting‐Li , Harbron Chris , Whitehead Anne
Published: March 2015

The identification of synergistic interactions between combinations of drugs is an important area within drug discovery and development. Pre‐clinically, large numbers of screening studies to identify synergistic pairs of compounds can often be ran, necessitating efficient and robust experimental designs. We consider experimental designs for detecting interaction between two drugs in a pre‐clinical in vitro assay in the presence of uncertainty of the monotherapy response. The monotherapies are assumed to follow the Hill equation with common lower and upper asymptotes, and a common variance. The optimality criterion used is the variance of the interaction parameter. We focus on ray designs and investigate two algorithms for selecting the optimum set of dose combinations. The first is a forward algorithm in which design points are added sequentially. This is found to give useful solutions in simple cases but can lack robustness when knowledge about the monotherapy parameters is insufficient. The second algorithm is a more pragmatic approach where the design points are constrained to be distributed log‐normally along the rays and monotherapy doses. We find that the pragmatic algorithm is more stable than the forward algorithm, and even when the forward algorithm has converged, the pragmatic algorithm can still out‐perform it. Practically, we find that good designs for detecting an interaction have equal numbers of points on monotherapies and combination therapies, with those points typically placed in positions where a 50% response is expected. More uncertainty in monotherapy parameters leads to an optimal design with design points that are more spread out. Copyright © 2015 John Wiley & Sons, Ltd.
The Androgenic Alopecia Protective Effects of Forsythiaside‐A and the Molecular Regulation in a Mouse Model
Authors: Shin Heon‐Sub , Park Sang‐Yong , Song Hyun‐Geun , Hwang Eunson , Lee Don‐Gil , Yi Tae‐Hoo
Published: March 2015

This study examined the inhibitory effect of forsythiaside‐A, a natural substance derived from Forsythia suspensa (F. suspensa), on entry into catagen induced by dihydrotestosterone (DHT) in an androgenic alopecia mouse model. In vitro experiment comparing finasteride with forsythiaside‐A showed that forsythiaside‐A treatment resulted in a 30% greater inhibition of DHT‐induced apoptosis in human hair dermal papilla cell (HHDPCs) and human keratinocytes (HaCaTs). In vivo experiment showed that mouse hair density and thickness were increased by 50% and 30%, respectively, in the forsythiaside‐A‐treated group when compared to a DHT group. Tissue histological results revealed that the forsythiaside‐A‐treated group had an increase in size and shape of the hair follicles and a 1.5 times increase in the follicle anagen/telogen ratio when compared to the finasteride group. Western blot examination of TGF‐β2 expression related to apoptosis signaling in mouse skin verified that forsythiaside‐A reduced the expression of TGF‐β2 by 75% and suppressed apoptosis by reducing the expression of caspase‐9 by 40%, and caspase‐3 by 53%, which play an roles up‐regulator in the apoptosis signal. The forsythiaside‐A group also showed a 60% increase in the Bcl‐2/Bax ratio, which is a factor related to mitochondrial apoptosis. Our results indicated that forsythiaside‐A prevents apoptosis by similar mechanism with finasteride, but forsythiaside‐A is more effective than finasteride. In summary, forsythiaside‐A controlled the apoptosis of hair cells and retarded the entry into the catagen phase and therefore represents a natural product with much potential for use as a treatment for androgenic alopecia. Copyright © 2015 John Wiley & Sons, Ltd.
Castalagin Exerts Inhibitory Effects on Osteoclastogenesis Through Blocking a Broad Range of Signaling Pathways with Low Cytotoxicity
Authors: Iwatake Mayumi , Okamoto Kuniaki , Tanaka Takashi , Tsukuba Takayuki
Published: March 2015

Castalagin is a rare plant polyphenol that is classified as a hydrolyzable tannin. Although it has antioxidant, antitumorigenic, and leishmanicidal effects, the utility of castalagin against bone diseases remain to be elucidated. Here, we investigated the effects of castalagin on the differentiation of osteoclasts (OCLs), multinucleated bone‐resorbing cells. After stimulation with receptor activator of nuclear factor kappa‐B ligand (RANKL), the formation of OCLs from bone marrow‐derived macrophages was significantly inhibited by castalagin even at 1 μM. However, castalagin displayed little cytotoxicity at a higher concentration of 50 μM. The effects of castalagin on intracellular signaling during OCL differentiation showed that castalagin suppresses RANKL‐stimulated phosphorylation of major signaling pathways including protein kinase B (Akt), extracellular signal‐regulated kinase, Jun N‐terminal kinase, p38 mitogen‐activated protein kinases, and inhibitor of nuclear factor kappa B alpha. Moreover, following castalagin treatment, the protein levels of nuclear factor of activated T‐cells, cytoplasmic 1, a master regulator for OCL differentiation, and NF‐κB were decreased. Thus, castalagin exerts inhibitory effects on osteoclastogenesis through blockage of a broad range of signaling pathways, but has low cytotoxicity. Copyright © 2015 John Wiley & Sons, Ltd.
Monitoring of Time‐Between‐Events with a Generalized Group Runs Control Chart
Authors: Fang Yen Yen , Khoo Michael B. C. , Teh Sin Yin , Xie Min
Published: March 2015

Control charting methods for time between events (TBE) is important in both manufacturing and nonmanufacturing fields. With the aim to enhance the speed for detecting shifts in the mean TBE, this paper proposes a generalized group runs TBE chart to monitor the mean TBE of a homogenous Poisson failure process. The proposed chart combines a TBE subchart and a generalized group conforming run length subchart. The zero‐state and steady‐state performances of the proposed chart were evaluated by applying a Markov chain method. Overall, it is found that the proposed chart outperforms the existing TBE charts, such as the T, Tr, EWMA‐T, Synth‐Tr, and GR‐Tr charts. Copyright © 2015 John Wiley & Sons, Ltd.
Change‐Point Detection for Shifts in Control Charts Using EM Change‐Point Algorithms
Authors: Chang Shao‐Tung , Lu Kang‐Ping
Published: March 2015

Knowing the time of changes in mean and variance in a process is crucial for engineers to identify the special cause quickly and correctly. Because assignable causes may give rise to changes in mean and variance at the same time, monitoring the mean and variance simultaneously is required. In this paper, a mixture likelihood approach is proposed to detect shifts in mean and variance simultaneously in a normal process. We first transfer the change point model formulation into a mixture model and then employ the expectation and maximization algorithm to estimate the time of shifts in mean and variance simultaneously. The proposed method called EMCP (expectation and maximization change point) can be used in both phase I and II applications without the knowledge of in‐control process parameters. Moreover, EMCP can detect the time of multiple shifts and simultaneously produce the estimates of shifts in each individual segment. Numerical data and real datasets are employed to compare EMCP with the direct statistical maximum likelihood method without the use of mixture models. The experimental results show the superiority and effectiveness of the proposed EMCP. The outperformance of EMCP in detecting the time of small shifts is particularly important and beneficial for engineers to identify assignable causes rapidly and accurately in phase II applications in which small shifts occur more often and hence lead to a large average run length. Copyright © 2015 John Wiley & Sons, Ltd.
First‐principles approaches for strongly correlated materials: A theoretical chemistry perspective
Authors: Jiang Hong
Published: March 2015

First‐principles treatment of strongly correlated systems is currently regarded as one of greatest challenges in theoretical chemistry and condensed matter physics. While great efforts have been invested to extend current electronic structure theories to treat strong correlation, there is also increasing interest in combining first‐principles approaches with model Hamiltonians to take advantage of the best of the two theoretical frameworks. This short review aims at giving an overview of first‐principles approaches that are currently used for strongly correlated materials, and remarking on their underlying physical ideas and theoretical limitations. © 2015 Wiley Periodicals, Inc.
Determination of low concentrations of iron, arsenic, selenium, cadmium, and other trace elements in natural samples using an octopole collision/reaction cell equipped quadrupole‐inductively coupled plasma mass spectrometer
Authors: Dial Angela R. , Misra Sambuddha , Landing William M.
Published: March 2015

Rationale

Accurate determination of trace metals has many applications in environmental and life sciences, such as constraining the cycling of essential micronutrients in biological production and employing trace metals as tracers for anthropogenic pollution. Analysis of elements such as Fe, As, Se, and Cd is challenged by the formation of polyatomic mass spectrometric interferences, which are overcome in this study.

Methods

We utilized an Octopole Collision/Reaction Cell (CRC)‐equipped Quadrupole‐Inductively Coupled Plasma Mass Spectrometer for the rapid analysis of small volume samples (~250 μL) in a variety of matrices containing HNO3 and/or HCl. Efficient elimination of polyatomic interferences was demonstrated by the use of the CRC in Reaction Mode (RM; H2 gas) and in Collision‐Reaction Mode (CRM; H2 and He gas), in addition to hot plasma (RF power 1500 W) and cool plasma (600 W) conditions.

Results

It was found that cool plasma conditions with RM achieved the greatest signal sensitivity while maintaining low detection limits (i.e. 56Fe in 0.44 M HNO3 has a sensitivity of 160,000 counts per second (cps)‐per‐1 µg L–1 and a limit of detection (LoD) of 0.86 ng L–1). The average external precision was ≤ ~10% for minor (≤10 µg L–1) elements measured in a 1:100 dilution of NIST 1643e and for iron in rainwater samples under all instrumental operating conditions.

Conclusions

An improved method has been demonstrated for the rapid multi‐element analysis of trace metals that are challenged by polyatomic mass spectrometric interferences, with a focus on 56Fe, 75As, 78Se and 111Cd. This method can contribute to aqueous environmental geochemistry and chemical oceanography, as well as other fields such as forensic chemistry, agriculture, food chemistry, and pharmaceutical sciences. Copyright © 2015 John Wiley & Sons, Ltd.
Chronic granulomatous disease presenting as refractory pneumonia in late adulthood
Authors: Sarwar Ghulam , de Malmanche Theo , Rassam Loui , Grainge Christopher , Williams Andrew , Arnold David
Published: March 2015

We present a case of refractory pneumonia in an adult patient with underlying chronic granulomatous disease (CGD). Her lobectomy tissue grew Burkholderia cepacia and histopathology revealed diffuse severe pneumonic consolidation with suppurative/necrotizing granulomata. An initial attempt to find an underlying immune deficiency was unsuccessful. Following recurrent invasive infections, repeat immunological assessment revealed reduced neutrophil function, demonstrating skewed carrier status (lyonization) for X‐linked CGD (only 3% normal cells). A pathogenic mutation in the CYBB gene was found on sequencing. CYBB gene encodes the gp91phox, a catalytic subunit of nicotinamide adenine dinucleotide phosphate‐oxidase that produces reactive oxygen species in phagocytes. Lyonization increases with age, explaining the delayed clinical CGD. CGD is a rare neutrophil disorder that usually presents in early life with recurrent infections due to bacteria and fungi primarily involving lungs and skin. It is secondary to a defective NADPH oxidase system needed to kill intracellular organisms and activate the formation of neutrophil extracellular traps.
Adaptive sliding mode control for a general nonlinear multicompartment lung model with input pressure and rate saturation constraints
Authors: Hou Saing Paul , Meskin Nader , Haddad Wassim M.
Published: March 2015

In this article, we develop an output feedback adaptive sliding mode controller for a general multicompartment lung mechanics model with nonlinear resistance and compliance respiratory parameters. Specifically, for a given clinically plausible reference volume pattern, we develop an adaptive sliding mode controller that accounts for input pressure and rate saturation constraints to automatically adjust the applied input pressure by the mechanical ventilator so that the total lung volume tracks the given reference pattern. The pressure due to lung muscle activity is also considered in the controller design. A Lyapunov‐based approach is presented to show convergence of the closed‐loop system, and the proposed control framework is applied to a two‐compartment lung model to show the efficacy of the proposed control method. Copyright © 2015 John Wiley & Sons, Ltd.
Sustainable Development in EU Countries: Concept and Rating of Levels of Development
Authors: Grzebyk Mariola , Stec Małgorzata
Published: March 2015

Sustainable development is indeed a complex phenomena, thus making the comparison and valuation of advances of EU‐member states in the implementation of its objectives specifically difficult. The authors attempted to establish a synthetic measure of the level of sustainable development taking into account simultaneously three components: economic, social and environmental. It was aimed to compare particular countries by the mentioned measure and then grouping them. Relying on basis of content aspects the basics of research were “headline indicators” of sustainable development, sourced from the 2005–2012 research period formed the premise of the study. The study results demonstrate ongoing gradual advances being made in the implementation of concepts of sustainable development in EU‐member states. Although there can be visible a gradual convergence of EU‐member states in respect of their levels of sustainable development, nonetheless majority of countries still post indicators of sustainable development below the EU average, especially those which recently became members of the European Union. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment
Carbon‐Based Sorbents with Three‐Dimensional Architectures for Water Remediation
Authors: Chen Bo , Ma Qinglang , Tan Chaoliang , Lim Teik‐Thye , Huang Ling , Zhang Hua
Published: March 2015

Over the past decade, carbon‐based 3D architectures have received increasing attention in science and technology due to their fascinating properties, such as a large surface area, macroscopic bulky shape, and interconnected porous structures, enabling them to be one of the most promising materials for water remediation. This review summarizes the recent development in design, preparation, and applications of carbon‐based 3D architectures derived from carbon nanotubes, graphene, biomass, or synthetic polymers for water treatment. After a brief introduction of these materials and their synthetic strategies, their applications in water treatment, such as the removal of oils/organics, ions, and dyes, are summarized. Finally, future perspective directions for this promising field are also discussed.
The toughness and morphology of (chlorinated poly[vinyl chloride])/(methyl methacrylate‐butadiene‐styrene) blends
Authors: Ren Liang , Zhang Shenwei , Zhang Mingyao , Chen Dan , Zhu Fupeng
Published: March 2015

A series of methyl methacrylate‐butadiene‐styrene (MBS) graft copolymers were synthesized via seeded emulsion polymerization techniques by grafting styrene and methyl methacrylate on poly(butadiene‐co‐styrene) (SBR) particles. The chlorinated poly(vinyl chloride) (CPVC)/MBS blends were obtained by melting MBS graft copolymers with CPVC resin, and the effect of the core/shell ratio of MBS graft copolymer and SBR content of CPVC/MBS blends on the mechanical properties and morphology of CPVC/MBS blends was studied. The results showed that, with the increase in the core/shell ratio, the impact strength of the blend increased and then decreased. It was found that, when the core/shell ratio was 50/50, the impact strength was about 155 J/m, and the tensile strength evidently increased. The toughness of the CPVC/MBS blend was closely related to the SBR content of the blend, and with the increasing of SBR content of blend, the impact strength of the blend increased. The morphology of CPVC/MBS blends was observed via scanning electron microscopy. Scanning electron microscopy indicated that the toughness of CPVC/MBS blend was consistence with the dispersion of MBS graft copolymers in the CPVC matrix. J. VINYL ADDIT. TECHNOL., 22:501–505, 2016. © 2015 Society of Plastics Engineers
Interfacial adhesion evaluation in (low‐density polyethylene)/elastomer blends
Authors: Formela Krzysztof , Piszczyk Łukasz , Haponiuk Józef , Bajer Krzysztof , Formela Magdalena
Published: March 2015

Low‐density polyethylene (LDPE) with different elastomers at a ratio of 50/50 wt% blends was prepared by using a co‐rotating twin‐screw extruder. Three kinds of elastomers were used: ground tire rubber (GTR), partially crosslinked butyl rubber (Kalar®), and styrene‐butadiene‐rubber block copolymer (SBS; Kraton®). For better characterization of interaction between polyethylene and elastomer, influence of the type of elastomer on the properties of compositions LDPE/elastomer was determined. In the studies, two types of partially crosslinked butyl rubber (differing over filler content and Mooney viscosity) and two types of SBS (differing over structure: linear/branched) were used. The influence of kind and type of elastomer on static mechanical properties (tensile strength, elongation at break, hardness), dynamic mechanical properties, thermal properties, and morphology of obtained compositions were characterized. LDPE/linear SBS copolymer blend had the best mechanical properties, as a result of better compatibility in comparison with other investigated blends. The reason for improved compatibility was an increase of mobility of chain segments in the amorphous phase of polyethylene associated with their partial plasticization by flexible polybutadiene blocks present in SBS copolymer. J. VINYL ADDIT. TECHNOL., 22:492–500, 2016. © 2015 Society of Plastics Engineers
Computational estimation of pKa values
Authors: Seybold Paul G. , Shields George C.
Published: March 2015

The pKa of a compound is one of its most important properties as it defines the specific molecular forms that will prevail under different pH conditions. Accordingly, accurate means for computational estimation of this property are of particular interest. Two main techniques for this purpose have emerged: (1) a first principles approach that relies on basic physical concepts and requires high computational resources, but is independent of experimental input and (2) a linear free energy or quantitative structure–activity relationship (QSAR) approach that combines molecular structural and energetic descriptors with available experimental pKa data to reduce computational demand and yield good accuracy. In this overview, these methods are described and their advantages and limitations are noted. WIREs Comput Mol Sci 2015, 5:290–297. doi: 10.1002/wcms.1218

This article is categorized under:

Structure and Mechanism > Molecular Structures

Structure and Mechanism > Computational Biochemistry and Biophysics

Computer and Information Science > Chemoinformatics
Future energy system development depends on past learning opportunities
Authors: Wene Clas‐Otto
Published: March 2015

Learning curves pervade all levels of industry and suggest deployment programs to buy down the cost of presently too expensive environment‐friendly technologies. However, the legitimate role of learning curves in a low‐carbon strategy depends on the validity of extrapolations and forecasts of the curves. Moving toward a technology‐led strategy for a low‐carbon energy system requires understanding of the learning mechanisms and their stability. The first part of this review provides examples of pervasive learning and a brief literature survey of recent learning curve measurements for energy technologies and the use of learning curves for scenario and policy analysis. The second part reviews how authors from two different perspectives understand the learning curves and come to different conclusions about their stability and legitimate role in scenario analysis and policy making.WIREs Energy Environ2016, 5:16–32. doi: 10.1002/wene.172

This article is categorized under:

Energy Systems Economics > Economics and Policy

Energy and Climate > Economics and Policy

Energy Policy and Planning > Economics and Policy

Energy Research & Innovation > Economics and Policy
X‐ray fluorescence of archived bone samples: are raised Pb levels a chance finding or an association with Paget's disease?
Authors: Egden Lesley M , Nguyen Khanh , Chettle David R , Butler Richard , Inskip Michael J , Webber Colin E
Published: March 2015

The K‐shell X‐ray fluorescence technique that was developed for measurement of lead in bone in living human subjects was applied to measurement of lead in archived human bone samples. The skull from a person who had suffered from Paget's disease was found to have lead concentrations of 97.5±3.6–532.2±3.2 µg Pb/g bone mineral. A femur sample from a different person, who had also suffered from Paget's disease, had a lead concentration of 18–43.5 with uncertainties between 1.6 and 2.0 µg Pb/g bone mineral. The skull lead concentrations were highly raised compared with findings from in vivo bone Pb measurements, whereas the femur lead concentrations were somewhat raised.

In the past, the hypothesis has been put forward that lead can be involved in the etiology of Paget's disease; however, other reports in the literature have not supported that hypothesis. The current findings, while intriguing, are too few to be in any way conclusive but merit further study. Copyright © 2015 John Wiley & Sons, Ltd.
Effect of Dicarboxylato Ligands on the Self‐Assembly of Two Cadmium(II) Coordination Polymers Containing Multidentate N‐donor Ligands
Authors: Kan Wei‐Qiu , Wen Shi‐Zheng , Hu Hua‐You , An Li‐Tao , Kan Yu‐He
Published: March 2015

Two CdII‐containing coordination polymers based on a multidentate N‐donor ligand and two structure‐related dicarboxylate ions, namely, [Cd2(3,4′‐tmbpt)(o‐bdc)2]·2H2O (1) and [Cd2(3,4′‐tmbpt)2(p‐bdc)2]·6.5H2O (2) [3,4′‐tmbpt = 1‐((1H‐1,2,4‐triazol‐1‐yl)methyl)‐3‐(4‐pyridyl)‐5‐(3‐pyridyl)‐1,2,4‐triazole, o‐H2bdc = 1,2‐benzenedicarboxylic acid, and p‐H2bdc = 1,4‐benzenedicarboxylic acid], were prepared under hydrothermal conditions. The structures of the two compounds were determined by single‐crystal X‐ray diffraction analysis and further characterized by infrared spectra (IR) and elemental analysis. Compound 1 is a 3D framework containing infinite Cd–O chains. Compound 2 displays a 2D → 2D interdigitated architecture. The effect of the dicarboxylate ions on the structures of the compounds was discussed. Moreover, the optical bandgaps and photoluminescent properties of the compounds were investigated.
Ammonothermal Synthesis and Characterization of Li4[Zn(NH2)4](NH2)2
Authors: Richter Theresia M. M. , Alt Nicolas S. A. , Schlücker Eberhard , Niewa Rainer
Published: March 2015

Single crystals of Li4[Zn(NH2)4](NH2)2 were obtained from Li and Zn under ammonothermal conditions (723 K and 1.58 kbar). Li4[Zn(NH2)4](NH2)2 (C2221, a = 5.0005(3) Å, b = 15.5410(8) Å, c = 10.0712(5) Å, Z = 4) represents a new possible intermediate in a conceivable ammonothermal synthesis of the semiconductor Zn3N2. Single crystal X‐ray diffraction results, thermal analysis, Raman and IR spectra of tetralithium tetraamido zincate diamide are provided and discussed. Crystal structure data justify a description as CaF2 superstructure variant. Large distances in the crystal structure as well as the intensity and half‐width of the bands in Raman and IR spectra indicate the absence of significant hydrogen bonds. Upon heating Li4[Zn(NH2)4](NH2)2 decomposes via intermediate formation of LiZnN, LiNH2 and Li2(NH) to finally provide pure Zn.
The effective solution of two‐dimensional integro‐differential equations and their applications in the theory of viscoelasticity
Authors: Shavlakadze Nugzar
Published: March 2015

The effective solutions for integro‐differential equations related to problems of interaction of an elastic thin finite inclusion with a plate, when the inclusion and plate materials possess the creep property are constructed. If the geometric parameter of the inclusion is measured along its length according to the parabolic and linear law we have managed to investigate the obtained boundary value problems of the theory of analytic functions and to get exact solutions and establish behavior of unknown contact stresses at the ends of an elastic inclusion.
Major Esophageal Dilation After Laparoscopic Adjustable Gastric Banding in Symptomatic Patients: Does It Prevent Effective Weight Loss and How Should It be Treated?
Authors: Ulmer Tom Florian , Ambe Peter , Alizai H. P. , Lambertz A. , Rheinwald K. , Plamper A. , Son M. , Tuerler A. , Gärtner D. , Neumann U.
Published: March 2015

Introduction

Esophageal dilation (ED) has been described as a long‐term complication following laparoscopic adjustable gastric banding (LAGB) with an incidence of 0.5–50 %. The purpose of this study was to evaluate the effect of major ED on weight loss and find methods to diagnose ED and possible treatment strategies based on a classification.

Materials and methods

We performed a retrospective analysis of all patients undergoing LAGB between 2004 and 2008 in three community‐based hospitals. ED was classified in four stages of dilation using gastrografin swallow. We report body mass index (BMI), failure rates and reoperations among these patients, with a mean follow‐up period of 6.7 years.

Results

Nineteen (18.4 %) of 103 patients who underwent LAGB presented with esophageal dilation. Band deflation failed for all nine patients (8.7 %) with major ED. The mean BMI at LAGB (BMI 1), revision (BMI 2), and 1 year after conversion (BMI 3) were 45.9 ± 3.2, 42.8 ± 4.9 and 30.3 ± 5.5 kg/m2, respectively. No significant difference was found comparing BMI 1 and BMI 2 (p = 0,065, EWL1: 14.2 ± 21.7 kg/m2). In contrast, the weight loss after the revision surgery was significant (p = 0.001, EWL2: 67.1 ± 30 kg/m2). No significant difference was found concerning age, gender, ASA, preoperative (LAGB) weight, and mean interval between LAGB and revision comparing patients with major ED (IV) to patients with milder forms (ED I‐III).

Conclusion

ED is a serious long‐term complication after LAGB and seems to prevent effective weight loss in stage IV. Furthermore, untreated dilation could cause long‐term damage to the esophagus. Therefore, we suggest routine radiographic follow‐up after LAGB even in asymptomatic patients and a treatment based on a classification with an early surgical revision for major ED.
Visceral Fat Content Correlates with Retroperitoneal Soft Tissue Sarcoma (STS) Local Recurrence and Survival
Authors: Papoulas Michail , Weiser Roi , Rosen Galia , Gerstenhaber Fabian , Merimsky Ofer , Lubezky Nir , Klausner Joseph M. , Lahat Guy
Published: March 2015

Background

Our aim was to evaluate the association between visceral fat content with soft tissue sarcoma (STS) local recurrence and survival.

Methods

One hundred and one computed tomography imaging studies of primary STS patients who had complete macroscopic resection at our institution between 2002 and 2012 were reviewed, and retroperitoneal and circumferential fat contents were measured. Correlations between imaging findings and clinical data were analyzed.

Results

Fifty‐seven STS tumors (56.4 %) were retroperitoneal; of them, 65 % were high grade, median size was 15 cm (range 3–49), and the most common histological subtype was high grade liposarcoma (31.6 %). Median follow‐up length for the entire cohort was 64 months (range 6–95). High visceral fat (VF) content ≥15 versus <15 mm was identified as a risk factor for retroperitoneal STS local recurrence; 65.1 versus 26.7 %, respectively (p = 0.04); VF content did not correlate with distant metastasis. Median overall survival (OS) length of patients with VF ≥15 versus <15 mm was 57 months (range 2–144) versus not reached, respectively (p = 0.007). Multivariable analysis identified VF ≥15 mm as an independent risk factor for decreased OS (HR: 4.2, 95 % CI 1.07–16.67). In contrast, circumferential fat content did not correlate with retroperitoneal STS patient outcomes.

Conclusion

High VF content is an independent adverse prognosticator associated with significantly higher rates of retroperitoneal STS local recurrence and decreased patients survival. Local tumor biology may be affected by the presence of adipose cells. Further clinical and molecular research is needed to establish this premise.
The Wonderful Century
Authors: Wallace Alfred Russel
Published: March 2015

The British naturalist and explorer Alfred Russel Wallace (1823–1913) was one of the leading evolutionary thinkers of the nineteenth century. He is best known for working in parallel with Darwin on evolution and natural selection. A social reformer and a prolific writer, he criticised the social and economic system in nineteenth-century Britain, and raised concerns over the environmental impact of human activity. First published in 1898, this book looks back over the history of the nineteenth century, and describes its material and intellectual achievements with the aim 'to show how fundamental is the change they have effected in our life and civilization'. The book surveys technological inventions such as the railway, the telegraph and telephone, as well as photography. But it also analyses the century's 'failures', and discusses the issues of poverty, greed and militarism.
GARY BECKER’S LEGACY ON INTERGENERATIONAL MOBILITY
Authors: Guner Nezih
Published: March 2015

How well do parents’ education, earnings, income, and wealth predict the same outcomes for their children? Scientists have been trying to answer this question for a long time. Francis Galton (1822–1911) was the first to apply statistical methods to tackle this question. Centuries earlier, the great Arab scholar Ibn Khaldun (1332–1406) famously observed that the prestige lasted at best four generations in one lineage.
Should the smiling curve frown during an economic downturn to enhance firm performance?
Authors: Luan Chin-jung , Tien Chengli
Published: March 2015

This study examines the efficacy of the smiling curve, and clarifies the relationship between downsizing strategies (advertising, marketing, and research and development, respectively) and firm performance specifically in an economic downturn. This study tests hypotheses using 1996–2010 data from the Taiwan Economic Journal on 436 listed Taiwanese companies. The results indicate that the benefits for firms to follow the smiling curve may not occur in the short term and that downsizing strategies may not always be the appropriate strategy to improve firm performance. During an economic downturn, downsizing strategies do not appear to enhance firm performance, that is, the smiling curve should not frown during an economic downturn to enhance firm performance.
An Early Upper Palaeolithic decorated bone tubular rod from Pod Hradem Cave, Czech Republic
Authors: Wright Duncan , Nejman Ladislav , d'Errico Francesco , Králík Miroslav , Wood Rachel , Ivanov Martin , Hladilová Šárka
Published: March 2015

Personal ornaments are a notable feature of the Early Upper Palaeolithic in Europe and an important expression of modern human identity. The tubular bone rod from Pod Hradem Cave in the Czech Republic is the first example of its kind from Central Europe. Laboratory examination reveals the techniques used in its manufacture and underlines the skill of its maker. AMS dates and Bayesian modelling suggest a cultural association with the Early Aurignacian period. It illustrates the cultural links across large areas of Europe at this time, although it is unique in its specific combination of size, raw material and decorative features.
Immortals in a foreign land: the Kargaly diadem
Authors: Linduff Katheryn M.
Published: March 2015

Spectacular objects may carry powerful messages about cultural affinities and legitimation. Such is the case set out here for the Kargaly diadem, supposedly a headpiece, of gold and semi-precious stones buried in a pit on the southern edge of the steppe in the northern foothills of the Tianshan mountains some 2000 years ago. This was a period when the Han Empire of China was seeking to increase its hold over the western borderlands and it is in that context, and the fluctuating rivalries of local polities, that the Kargaly diadem is to be understood. Chinese iconography figures prominently on the diadem which may have been a diplomatic gift from the Han imperial court, but technological details suggest that it was produced within the western borderlands beyond China itself. The combination of Chinese and other elements testify to the fluidity of cultural interaction around the borders of the expanding Han Empire and the imitation and incorporation of symbols of power by contending local elites.
The difficulties of dating olive wood
Authors: Kuniholm Peter Ian
Published: March 2015

Olive wood is difficult to date for a variety of reasons, the most important of which is that one cannot tell visually what is an annual growth increment (usually referred to as a ‘ring’) and what is a sub-annual growth flush of which there may be any number in one growing season. (I have been able to count a dozen or more flushes in olive wood where the end of the growing season was somewhat more clearly marked than usual.) If one cannot determine the ring boundaries with certainty, one cannot do tree-ring dating, period. For Egyptologists reading this note, acacia is just as bad, and for the same reason. For 25 years I had a couple of sections of olive wood in my dendrochronology lab. Every term I would challenge students to tell me how many rings there were on them. No two students ever came up with the same answer and neither could I. An inspection of two different radii on the same piece also yielded widely varying results. (A side issue, not relevant here, is that the size of the ring in an olive tree does not necessarily reflect climatic conditions but rather the energies of the farmer or gardener who brings water to it. Thus olive is useless for purely dendrochronological cross-dating purposes.
Identifying ceramic production and exchange in the Valley of Puebla, Mexico: a multifaceted approach
Authors: Castanzo Ronald A.
Published: March 2015

Pottery production in Formative Period Mesoamerica appears to have been organised at the household level, but its distribution also provides evidence of political or economic boundaries. One distinctive ware from the Valley of Puebla, Tlaquexpa Red, used for the manufacture of sub-hemispherical bowls, was analysed by instrumental neutron activation analysis. The results indicated that many of these vessels were being made by families at Tlaquexpa itself, but that some of their products were being traded to other communities, including the nearby civic-ceremonial centre of Xochiltenango. The study gives new insight into the role of pottery production in pre-Hispanic households.
From the Iron Age to Angkor: new light on the origins of a state
Authors: Higham Charles
Published: March 2015

Excavations at four Iron Age moated sites in the Mun Valley in Thailand have identified seminal innovations, defined as emergent properties, that illuminate the origins of the kingdom of Angkor. Combined with recent research at Angkor itself, they present a compelling case for re-examining fundamental cultural changes that took place over a period of little more than four centuries, from AD 400–800. They compare with similarly rapid developments in Mesoamerica and Mesopotamia; fundamental parallels are evident in the role of charismatic agents for change, an ideology conferring god-like status on leaders, a new and highly productive economic base, an expanded interaction sphere for the exchange of prestige goods, and endemic warfare.
The arboreal origins of human bipedalism
Authors: Thorpe Susannah K.S. , McClymont Juliet M. , Crompton Robin H.
Published: March 2015

Almost a century and a half ago, Charles Darwin inThe Descent of Man(1871: 141) highlighted the evolution of bipedalism as one of the key features of the human lineage, freeing the hands for carrying and for using and making tools. But how did it arise? The famous footprints from Laetoli in Tanzania show that hominin ancestors were walking upright by at least 3.65 million years ago. Recent work, however, suggests a much earlier origin for bipedalism, in a Miocene primate ancestor that was still predominantly tree-dwelling. Here Susannah Thorpe, Juliet McClymont and Robin Crompton set out the evidence for that hypothesis and reject the notion that the common ancestor of great apes and humans was a knuckle-walking terrestrial species, as are gorillas and chimpanzees today. The article is followed by a series of comments, rounded off by a reply from the authors.