bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced thermal stability of biomedical thermoplastic polyurethane with the addition of cellulose nanocrystals
Authors: Liu Jen‐Chieh , Martin Darren J. , Moon Robert J. , Youngblood Jeffrey P.
Published: February 2015

Freeze‐dried cellulose nanocrystals (CNCs) were dispersed in the thermoplastic polyurethane [Pellethane 2363‐55D (P55D)] by a solvent casting method to fabricate CNC‐reinforced nanocomposites. This study demonstrated that the addition of small amounts (1–5 wt %) of CNCs to P55D increased the thermal degradation temperature while maintaining a similar stiffness, strength, and elongation of the neat P55D. CNC additions to P55D did not alter the glass‐transition temperature, but the onset decomposition temperature was shifted from 286 to 327°C when 1 wt % CNCs was dispersed in the matrix. The higher onset decomposition temperature was attributed to the formation of hydrogen bonds between the hydroxyl groups on the CNC surface and urethane groups in the hard block of P55D. The ultimate tensile strength and strain to failure (εf) of the nanocomposites were minimally affected by additions up to 5 wt % CNCs, whereas the elastic modulus was increased by about 70%. The observation that εf was unchanged with the addition of up to 5 wt % CNCs suggested that the flow/sliding of the hard blocks and chains were not hindered by the presence of the CNCs during plastic deformation. The ramifications of this study was that CNC additions resulted in wider processing temperatures of P55D for various biomedical devices while maintaining a similar stiffness, strength, and elongation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41970.
Preparation and characterization of Rana chensinensis skin extract/poly(ε‐caprolactone) electrospun membranes as antibacterial fibrous mats
Authors: Zhang Mei , Xu Wen‐Yu , Wang Jia‐Mian , Luan Jia‐Shuang , Dong He‐Nan , Zhang Yu‐Jing , Li Xue‐Qi , Sun Da‐Hui
Published: February 2015

In this study, membranes composed of Rana chensinensis skin extracts (RCSEs) and poly(ε‐caprolactone) (PCL) were fabricated by an electrospinning technique. The RCSEs were prepared by the extraction of R. chensinensis skin with acetic acid solution, and the electrospun membranes were prepared by the mixture of RCSEs and PCL in 1,1,1,3,3,3‐hexafluoro‐2‐propanol before electrospinning. The membranes were characterized by scanning electron microscopy and Fourier transform infrared spectroscopy and were subjected to mechanical tests (tensile and nanoindentation) and antibacterial evaluation. The results indicate that the surface roughness of the fibers clearly decreased with the increase in the amount of PCL in the membranes. The mechanical test indicated that PCL played a dominant role in the mechanical strength of the RCSE/PCL electrospun membranes. As a potential bactericidal packaging material for practical applications, the antibacterial activity results indicate that the membranes had antibacterial effects against Staphylococcus aureus and Escherichia coli. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42030.
Design, Synthesis and In Vitro Study of 5,6‐Diaryl‐1,2,4‐triazine‐3‐ylthioacetate Derivatives as COX‐2 and β‐Amyloid Aggregation Inhibitors
Authors: Dadashpour Sakineh , Tuylu Kucukkilinc Tuba , Unsal Tan Oya , Ozadali Keriman , Irannejad Hamid , Emami Saeed
Published: February 2015

In order to find novel cyclooxygenase (COX)‐2 inhibitors for treating inflammatory‐based diseases such as Alzheimer's disease (AD), an ethyl carboxylate side chain was added to 5‐(4‐chlorophenyl)‐6‐(4‐(methylsulfonyl)phenyl)‐3‐(methylthio)‐1,2,4‐triazine (lead compound II) to maintain residual inhibition of COX‐1 through interacting with Arg120. A preliminary molecular docking study on both the COX‐1/COX‐2 active sites truly confirmed our hypothesis. Accordingly, a series of ethyl 5,6‐diaryl‐1,2,4‐triazine‐3‐ylthioacetate derivatives were synthesized and their chemical structures were confirmed by NMR, IR and MS spectra. Further in vitro COX‐1/COX‐2 evaluations revealed that compound 6c (COX‐2 IC50 = 10.1 μM, COX‐1 IC50 = 88.8 μM) is the most selective COX‐2 inhibitor while maintaining residual inhibition of COX‐1. In order to evaluate their potential use against AD, an in vitro evaluation of β‐amyloid fibril formation was performed. The results indicated that the prototype compounds 6 are effective β‐amyloid destabilizing agents while compound 6c could inhibit 94% of the β‐amyloid fibril formation after 48 h. Finally, the in silico assessment results of their blood–brain barrier permeability were satisfactory.
The effects of pH and surfactants on the absorption and fluorescence properties of ochratoxin A and zearalenone
Authors: Li Taihua , Kim Bo Bae , Ha Tae Hwan , Shin Yong‐Beom , Kim Min‐Gon
Published: February 2015

The pH and surfactant dependencies of the absorption and fluorescence properties of ochratoxin A (OTA) and zearalenone (ZEN), the main mycotoxins found as contaminants in foods and feeds, were evaluated. Three surfactants with different ionic properties were investigated, namely sodium dodecyl sulfate (SDS, anionic), Tween 20 (nonionic) and hexadecyltrimethylammonium bromide (CTAB, cationic). The results show that the effects of pH on the absorption wavelength maxima and fluorescence efficiencies of the mycotoxins, which are a consequence of the presence of acidic phenol and/or carboxyl containing fluorophores, are dependent on the ionic nature of the added surfactants. Specifically, the fluorescence responses to pH changes of OTA and ZEN are similar in the presence or absence of Tween 20 and SDS. By contrast, the pH‐dependent fluorescence properties of these mycotoxins are altered when CTAB is present in the solutions. Moreover, unlike OTA, ZEN in aqueous solution displays almost no fluorescence. However, fluorescence enhancement takes place when surfactants are present in aqueous solutions of this mycotoxin. The results of this study demonstrate that the different microenvironments, present in the organized micellar systems created by the individual surfactants, can be potentially employed to modulate the sensitivities and selectivities of the fluorescence detection of OTA or ZEN. Copyright © 2015 John Wiley & Sons, Ltd.
Identification of a New Diterpene Biosynthetic Gene Cluster that Produces O‐Methylkolavelool in Herpetosiphon aurantiacus
Authors: Nakano Chiaki , Oshima Misaki , Kurashima Nodoka , Hoshino Tsutomu
Published: February 2015

Diterpenoids are usually found in plants and fungi, but are rare in bacteria. We have previously reported new diterpenes, named tuberculosinol and isotuberculosinol, which are generated from the Mycobacterium tuberculosis gene products Rv3377c and Rv3378c. No homologous gene was found at that time, but we recently found highly homologous proteins in the Herpetosiphon aurantiacus ATCC 23779 genome. Haur_2145 was a class II diterpene cyclase responsible for the conversion of geranylgeranyl diphosphate into kolavenyl diphosphate. Haur_2146, homologous to Rv3378c, synthesized (+)‐kolavelool through the nucleophilic addition of a water molecule to the incipient cation formed after the diphosphate moiety was released. Haur_2147 afforded (+)‐O‐methylkolavelool from (+)‐kolavelool, so this enzyme was an O‐methyltransferase. This new diterpene was indeed detected in H. aurantiacus cells. This is the first report of the identification of a (+)‐O‐methylkolavelool biosynthetic gene cluster.
Selective Oxidation of Salicylic Alcohol to Aldehyde with O2/H2 using Au‐Pd on Titanate Nanotubes Catalysts
Authors: Torrente‐Murciano Laura , Villager Thomas , Chadwick David
Published: February 2015

Alcohol oxidation with 100 % selectivity to the aldehyde product (versus acid formation) is achieved at mild conditions by a tandem‐type system where the intermediate species of hydrogen peroxide formation from an O2/H2 mixture are formed and utilised directly over Au‐Pd/Ti‐NT catalysts. In situ reaction of the intermediate species minimises the parallel decomposition of hydrogen peroxide into water, overcoming one of the limitations on the use of hydrogen peroxide as a green oxidant.
Self‐Assembled Discrete Molecules for Sensing Nitroaromatics
Authors: Shanmugaraju Sankarasekaran , Mukherjee Partha Sarathi
Published: February 2015

Efficient sensing of trace amount nitroaromatic (NAC) explosives has become a major research focus in recent time due to concerns over national security as well as their role as environment pollutants. NO2‐containing electron‐deficient aromatic compounds, such as picric acid (PA), trinitrotoluene (TNT), and dinitrotoluene (DNT), are the common constituents of many commercially available chemical explosives. In this article, we have summarized our recent developments on the rational design of electron‐rich self‐assembled discrete molecular sensors and their efficacy in sensing nitroaromatics both in solution as well as in vapor phase. Several π‐electron‐rich fluorescent metallacycles (squares, rectangles, and tweezers/pincers) and metallacages (trigonal and tetragonal prisms) have been synthesized by means of metal–ligand coordination‐bonding interactions, with enough internal space to accommodate electron‐deficient nitroaromatics at the molecular level by multiple supramolecular interactions. Such interactions subsequently result in the detectable fluorescence quenching of sensors even in the presence of trace quantities of nitroaromatics. The fascinating sensing characteristics of molecular architectures discussed in this article may enable future development of improved sensors for nitroaromatic explosives.
Serious Cardiac Complications in Coronary Spasm Provocation Tests Using Acetylcholine or Ergonovine: Analysis of 21 512 Patients From the Diagnosis Procedure Combination Database in Japan
Authors: Isogai Toshiaki , Yasunaga Hideo , Matsui Hiroki , Tanaka Hiroyuki , Ueda Tetsuro , Horiguchi Hiromasa , Fushimi Kiyohide
Published: February 2015

Background

Previous studies on complications with coronary spasm provocation tests were based on small sample sizes or were limited to high‐volume centers. The risk of provocation tests using acetylcholine (ACH) or ergonovine (ER) remains to be fully examined by a large‐scale multicenter study.

Hypothesis

ACH provocation tests are associated with a higher rate of serious cardiac complications than ER tests.

Methods

Using the Diagnosis Procedure Combination database in Japan, we identified patients aged ≥20 years who underwent a pharmacological provocation test during coronary angiography. We assessed the composite outcome of cardiac complications requiring urgent procedures (defibrillation, chest compression, intra‐aortic balloon pumping, or extracorporeal membrane oxygenation) or death on the day of the provocation test, and compared the outcome between ACH and ER tests.

Results

Of 21 512 eligible patients in 602 hospitals, 10 628 (49.4%) underwent an ACH test and 10 884 (50.6%) underwent an ER test. The composite outcome occurred in 141 (0.7%) patients. The ACH group was significantly more likely to have the composite outcome than the ER group (0.9% vs 0.4%, P < 0.001). The propensity‐score analyses showed consistent results (propensity score–matched, 0.9% vs 0.4%, P = 0.003; inverse probability–weighted, 0.8% vs 0.4%, P < 0.001). In a multivariable logistic regression analysis, ACH tests were significantly associated with a higher rate of the composite outcome than ER tests (odds ratio: 1.75, 95% confidence interval: 1.13‐2.69, P = 0.011).

Conclusions

This retrospective cohort study suggested that ACH tests were associated with a higher rate of cardiac complications than ER tests.
Toward interchangeable biologics
Authors: McCamish M , Pakulski J , Sattler C , Woollett G
Published: February 2015

A biosimilar is designed to match the reference product – to be as close to the reference as the reference is to itself considering batch‐to‐batch variability and manufacturing changes over its lifetime.1 Interchangeability will require additional data, however, the interchangeable biologic itself will be the same as that approved for biosimilarity.
A New Initiative With Multiple Sponsors to Help Prepare Medical Students to Be Safe and Effective Prescribers
Authors: Nierenberg D , Cannon E
Published: February 2015

Most medical schools in the US, and in other countries as well, continue to struggle to teach their medical students to be safe and effective prescribers before they graduate and set off for their residency programs. We describe a new initiative supported by several national organizations to help medical schools address this need by producing and making available online learning modules that can be used by medical students at any US medical school.
A novel energy‐efficient cross‐application‐layer platform with QoS‐security support
Authors: Adibi Sasan
Published: February 2015

Security provisioning is an essential part in the design of any communication systems, which becomes more critical for wireless systems. Devising a quality of service (QoS) mechanism to coexist security algorithms is a daunting, yet inevitable task. The aim of this novel research article is to present a novel energy efficient, cross‐layer‐based application‐layer wireless system with simultaneous security and QoS supports, which revolves around the practical and low‐cost implementation of Suite‐B cryptographic algorithms (promulgated by the National Security Agency) and detailed analyses of the associated complexities. The focus of this article is on the novel cross‐layer mechanism and its effectiveness to handle QoS‐enabled treatment while offering security enhancements. Copyright © 2015 John Wiley & Sons, Ltd.
Post‐harvest treatment with pure (+)‐methyl jasmonate minimizes lipid oxidation in boiled potato (Solanum tuberosum L.)
Authors: Flores Gema , de la Peña Moreno Fernando , Blanch Gracia Patricia , Ruiz del Castillo María Luisa
Published: February 2015

Linoleic and linolenic acids are health‐promoting compounds having a number of biological properties. In the present study, oxidative degradation of these fatty acids into off‐flavor compounds in boiled potato was intended to be reduced. To that end, raw potatoes were treated by applying: (i) the commercial mixture (±)‐methyl jasmonate, (ii) pure (+)‐methyl jasmonate, and (iii) pure (−)‐methyl jasmonate, respectively. Four cultivars (i.e., Cara, Inca Sun, Mayan Gold, and Maris Piper) were included in the study. As a result, the post‐harvest application of (±)‐methyl jasmonate and (+)‐methyl jasmonate to raw potatoes during storage resulted in a significant decrease of lipid‐derived volatile compounds in boiled potato. This suggests an inhibitory effect of both the commercial enantiomeric mixture and the pure (+)‐methyl jasmonate on the lipoxygenase pathway. Stabilization of linoleic and linolenic acids against autoxidation is achieved by treatment with the enantiomeric mixture and pure (+)‐methyl jasmonate. (−)‐Methyl jasmonate however exhibited the opposite effect since it did not reduce lipid oxidation in boiled potato. The results found in the present work support earlier evidence on different effects of methyl jasmonate enantiomers on plant food composition. From a practical point of view, post‐harvest treatments with (+)‐methyl jasmonate can be used by the potato industry to obtain healthier and more pleasant products.

Practical application The results found in the present study demonstrate that the practical applications of methyl jasmonate treatments minimize lipid oxidation in boiled potato. That allows us to obtain, on the one hand, tubers containing higher contents of linolenic and linoleic acids and, on the other, more pleasant flavor after boiling.

The exogenous application of (+)‐MJ to raw potato during storage enabled lipid oxidation in boiled potato to be reduced. Therefore, (+)‐MJ treatment might be used by the potato industry to obtain a healthier and more pleasant product.
A DAP12‐Dependent signal promotes pro‐inflammatory polarization in microglia following nerve injury and exacerbates degeneration of injured neurons
Authors: Kobayashi Masaaki , Konishi Hiroyuki , Takai Toshiyuki , Kiyama Hiroshi
Published: February 2015

Under pathological conditions, activated microglia play paradoxical roles and could have neurotoxic or neuroprotective effects. However, the signal determining how activated microglia affects the fate of neuronal cells remains largely unknown. Here we demonstrate that DNAX‐activating protein of 12 kDa (DAP12), a transmembrane adaptor protein that contains an immunoreceptor tyrosine‐based activation motif, is a critical regulator of microglial function after nerve injury. In a model of mouse hypoglossal nerve injury, the duration of microglial increase after nerve injury became shorter in mice lacking DAP12, although microglial morphology and total cell numbers were not significantly affected during early phase after nerve injury. Intriguingly, expressions of M1‐phenotype markers including pro‐inflammatory cytokines were suppressed in DAP12‐deficient microglia. Furthermore, axotomy‐induced motor neuron death was markedly prevented in DAP12‐deficient mice. Collectively, DAP12‐mediated microglial activation following axotomy promotes pro‐inflammatory responses, and thereby accelerates nerve injury‐induced neuron death, suggesting that DAP12 is a potential therapeutic target for the protection of neuronal degeneration caused by microglial activation. GLIA 2015;63:1073–1082
Aryl hydrocarbon receptor mediates both proinflammatory and anti‐inflammatory effects in lipopolysaccharide‐activated microglia
Authors: Lee Yi‐Hsuan , Lin Chun‐Hua , Hsu Pei‐Chien , Sun Yu‐Yo , Huang Yu‐Jie , Zhuo Jiun‐Horng , Wang Chen‐Yu , Gan Yu‐Ling , Hung Chia‐Chi , Kuan Chia‐Yi , Shie Feng‐Shiun
Published: February 2015

The aryl hydrocarbon receptor (AhR) regulates peripheral immunity; but its role in microglia‐mediated neuroinflammation in the brain remains unknown. Here, we demonstrate that AhR mediates both anti‐inflammatory and proinflammatory effects in lipopolysaccharide (LPS)‐activated microglia. Activation of AhR by its ligands, formylindolo[3,2‐b]carbazole (FICZ) or 3‐methylcholanthrene (3MC), attenuated LPS‐induced microglial immune responses. AhR also showed proinflammatory effects, as evidenced by the findings that genetic silence of AhR ameliorated the LPS‐induced microglial immune responses and LPS‐activated microglia‐mediated neurotoxicity. Similarly, LPS‐induced expressions of tumor necrosis factor α (TNFα) and inducible nitric oxide synthase (iNOS) were reduced in the cerebral cortex of AhR‐deficient mice. Intriguingly, LPS upregulated and activated AhR in the absence of AhR ligands via the MEK1/2 signaling pathway, which effects were associated with a transient inhibition of cytochrome P450 1A1 (CYP1A1). Although AhR ligands synergistically enhance LPS‐induced AhR activation, leading to suppression of LPS‐induced microglial immune responses, they cannot do so on their own in microglia. Chromatin immunoprecipitation results further revealed that LPS‐FICZ co‐treatment, but not LPS alone, not only resulted in co‐recruitment of both AhR and NFκB onto the κB site of TNFα gene promoter but also reduced LPS‐induced AhR binding to the DRE site of iNOS gene promoter. Together, we provide evidence showing that microglial AhR, which can be activated by LPS, exerts bi‐directional effects on the regulation of LPS‐induced neuroinflammation, depending on the availability of external AhR ligands. These findings confer further insights into the potential link between environmental factors and the inflammatory brain disorders. GLIA 2015;63:1138–1154
Solvatochromic shifts of Br2 and I2 in water cages of type 512, 51262, 51263, and 51264
Authors: Middendorf Nils , Krause Katharina , Höfener Sebastian
Published: February 2015

Despite the relatively small size of molecular bromine and iodine, the physicochemical behavior in different solvents is not yet fully understood, in particular when excited‐state properties are sought. In this work, we investigate isolated halogen molecules trapped in clathrate hydrate cages. Relativistic supermolecular calculations reveal that the environment shift to the excitation energies of the (nondegenerate) states
and
lie within a spread of 0.05 eV, respectively, suggesting that environment shifts can be estimated with scalar‐relativistic treatments. As even scalar‐relativistic calculations are problematic for excited‐state calculations for clathrates with growing size and basis sets, we have applied the subsystem‐based scheme frozen‐density embedding, which avoids a supermolecular treatment. This allows for the calculation of excited states for extended clusters with coupled‐cluster methods and basis sets of triple‐zeta quality with additional diffuse functions mandatory for excited‐state properties, as well as a facile treatment at scalar‐relativistic exact two‐component level of theory for the heavy atoms bromine and iodine. This simple approach yields scalar‐relativistic estimates for solvatochromic shifts introduced by the clathrate cages. © 2015 Wiley Periodicals, Inc.
Endoscopy of gastropods: A novel view of the mantle cavities and gills of the keyhole limpet Diodora aspera and the abalone Haliotis rufescens
Authors: Voltzow Janice
Published: February 2015

The gills, or ctenidia, of marine gastropods serve as the sites for respiratory gas exchange. Cilia on the surface provide the pump that moves water through the mantle cavity and enhance diffusion. Because the gills are housed inside the shell, it is difficult to view them while they are functioning. Published images of gills show contracted, fragile structures that are distorted by the processes of dissection and preservation. Members of the families Fissurellidae (keyhole limpets) and Haliotidae (abalone) have openings in their shells through which water enters and/or exits. I inserted an endoscope connected to a video camera into the openings of the shells of living, non‐anaesthetized individuals of the fissurellid Diodora aspera and the haliotid Haliotis rufescens. In both species, the dorsal afferent branchial vessel of the afferent gill axis appeared large and inflated, as did the leaflets that extended from either side of the axis. In D. aspera, the leaflets appeared to fill the mantle cavity and responded to touch, particles, and dye in the water by contracting quickly and slowly re‐extending. In contrast, the gills of H. rufescens did not noticeably respond to disturbance. On the other hand, these gills showed a regular pattern of pleats that had not been described in the extensive anatomical literature of these common and economically significant animals. These results provide a novel view of the gastropod mantle cavity as a dynamic space filled by the gills, which divide the mantle cavity into distinct incurrent and excurrent chambers and produce a laminar flow of water through the cavity. J. Morphol. 276:787–796, 2015. © 2015 Wiley Periodicals, Inc.
Dehydration of Na‐jarosite, ferricopiapite, and rhomboclase at temperatures of 50 and 95 °C: implications for Martian ferric sulfates
Authors: Liu Yang , Wang Alian
Published: February 2015

Ferric sulfates with various hydration degrees were found on Mars by surface exploration and orbital remote sensing. The processes that they experienced during their formation and alteration relate to Martian hydrologic history and thus have been important topics for laboratory investigations. This study reports three sets of dehydration experiments conducted on Na‐jarosite, ferricopiapite, and rhomboclase under two relative humidity conditions (5–6% RH and 10–11% RH) at two temperatures (50 and 95 °C), for which laser Raman spectroscopy and gravimetric measurements were the only two techniques used, in situ and non‐invasively, to monitor the progress of these experiments. Our dehydration experiments show that OH‐bearing Na‐jarosite is relatively stable at 95 °C and RH < 11%, while H2O/OH‐bearing ferricopiapite and rhomboclase have converted almost entirely into anhydrous phases. These results have important applications on uncovering the mystery of rarely detected Martian ferric sulfates and on interpreting Mars remote sensing data. Copyright © 2015 John Wiley & Sons, Ltd.
Gels Based on Anion Recognition Between Triurea Receptor and Phosphate Anion
Authors: Yang Cuiling , Wu Biao , Chen Yongming , Zhang Ke
Published: February 2015

Anion recognition between the triurea receptor and phosphate anion is demonstrated as the cross‐linkage to build supramolecular polymer gels for the first time. A novel multi‐block copolymer (3) is designed to have functional triurea groups as cross‐linking units along the polymer main chain. By virtue of anion coordination between the triurea receptor and phosphate anion with a binding mode of 2:1, supramolecular polymer gels are then prepared based on anion recognition using 3 as the building block.

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Experimental characterization and numerical assessment of fatigue crack growth under thermo‐mechanical conditions
Authors: Schlitzer T. , Bauerbach K. , Beier H. T. , Fischaleck M. , Langschwager K. , Oechsner M. , Rudolph J. , Scholz A. , Vormwald M. , Willuweit A.
Published: February 2015

The fatigue behavior of the austenitic stainless steel X6CrNiNb18‐10 (1.4550, AISI 347) is investigated. Experimental data are generated at room temperature, at elevated temperatures and further under thermo‐mechanical conditions. Research is focused on generating data for parameter identification, especially for the improvement of material models. The influence of temperature on the stress‐strain behavior and the fatigue life is presented.

Finite element simulations are used to describe fatigue crack growth under thermo‐cyclic loading conditions. Using the example of a thick‐walled tube, the essential parameter for the crack growth rate, the effective cyclic J‐integral, is determined for eight temperature transients (defined by fluid temperature, heat transfer coefficient and inner pressure). An approximation of the effective cyclic J‐integral allows modeling without consideration of the crack geometry in the model.
A fatigue design concept for metal injection molded components of 100Cr6
Authors: Lindel H. , Hahn M. , Bacher‐Höchst M. , Issler S. , Eifler D. , Klein M.
Published: February 2015

The fatigue behavior of rolled and machined high‐strength steel parts shows dependency on the size of material defects. In this work, the fatigue behavior of high‐strength steel specimens manufactured by Metal Injection Molding (MIM) process is investigated. Herein prealloyed 100Cr6 powder is used as base material and is sintered to 98.7% and to 95.2% relative density respectively. In order to avoid burrs resulting from the mold parting, an unconventional metal injection molding‐specific specimen shape is designed to perform experiments at notched and unmachined specimens, especially to assess the behavior of this material in component‐near conditions. Fatigue tests under axial loading with a load ratio of R = 0.1 were conducted with such specimens in martensitic condition. SEM analyses reveal that cracks originate from metal injection molding‐specific material discontinuities which can be seen as defects to this high strength steel. It was observed that irregularities at the surface, like surface roughness, open pores and locally melted surface areas lead to early fracture whereas defects in the volume, like non‐metallic inclusions lead to late fracture. Fracture mechanic analyses reveal that Murakami's short crack model is applicable to the 100Cr6 metal injection molding materials and therefore allows estimating the fatigue strength at N = 107 cycles of the metal injection molding‐material. Considering a weakest‐link approach, the fatigue strength at N = 107 cycles of the notched specimens can be well estimated using finite element modeling and the size distributions of the crack originating defects.
Tensile and fatigue behaviors of polymers for automotive applications
Authors: Mortazavian S. , Fatemi A.
Published: February 2015

An experimental study was conducted on tensile and fatigue behaviors of two unreinforced polymers and two short glass fiber reinforced polymer composites. A number of effects including anisotropy, strain rate and temperature on tensile behavior was investigated. Fatigue behavior was evaluated with respect to effects of mold flow direction, temperature, mean stress, and stress concentration. Effect of mold flow direction on both tensile and fatigue behaviors of unreinforced materials was found to be negligible, while it was significant for reinforced materials. Tsai‐Hill criterion commonly used for continuous fiber composites was used to predict the off‐axis fatigue strengths of short fiber reinforced materials. Effect of strain rate on tensile properties was found to be significant for all materials. Test temperature also influenced tensile and fatigue behaviors of both unreinforced and reinforced materials. Mathematical equations were developed to represent variations of tensile properties with both temperature and strain rate. Walker equation with a mean stress correction parameter is proposed to correct for the effect of mean stress. Effect of stress concentration combined with mold flow direction and mean stress was also investigated and Neuber's rule resulted in accurate estimation of fatigue life.
Fast Hankel tensor–vector product and its application to exponential data fitting
Authors: Ding Weiyang , Qi Liqun , Wei Yimin
Published: February 2015

This paper is contributed to a fast algorithm for Hankel tensor–vector products. First, we explain the necessity of fast algorithms for Hankel and block Hankel tensor–vector products by sketching the algorithm for both one‐dimensional and multi‐dimensional exponential data fitting. For proposing the fast algorithm, we define and investigate a special class of Hankel tensors that can be diagonalized by the Fourier matrices, which is called anti‐circulant tensors. Then, we obtain a fast algorithm for Hankel tensor–vector products by embedding a Hankel tensor into a larger anti‐circulant tensor. The computational complexity is about for a square Hankel tensor of order m and dimension n, and the numerical examples also show the efficiency of this scheme. Moreover, the block version for multi‐level block Hankel tensors is discussed. Copyright © 2015 John Wiley & Sons, Ltd.
Reversible Mechanical Switching of Magnetic Interactions in a Molecular Shuttle
Authors: Bleve Valentina , Schäfer Christian , Franchi Paola , Silvi Serena , Mezzina Elisabetta , Credi Alberto , Lucarini Marco
Published: February 2015

Invited for this months cover are the groups of Professors Marco Lucarini and Alberto Credi at the University of Bologna. The cover picture shows coupled and uncoupled states of a [2]rotaxane incorporating stable nitroxide radical units in both the ring and dumbbell components. Interaction between nitroxide radicals could be switched between noncoupled (three‐line electron paramagnetic resonance (EPR) spectrum) and coupled (five‐line EPR spectrum) upon deprotonation of the rotaxane NH2+ centers that effects a quantitative displacement of a dibenzocrown macroring to a 4,4’‐bipyridinium recognition site. The complete base‐ and acid‐induced switching cycle of the EPR pattern was repeated several times without an appreciable loss of signal, highlighting the reversibility of the process. Hence, this molecular machine is capable of switching on/off magnetic interactions by chemically driven reversible mechanical effects. For more details, see the Communication on p. 18 ff.
Implications of low breakdown voltage of component subcells on external quantum efficiency measurements of multijunction solar cells
Authors: Barrigón Enrique , Espinet‐González Pilar , Contreras Yedileth , Rey‐Stolle Ignacio
Published: February 2015

The electrical and optical coupling between subcells in a multijunction solar cell affects its external quantum efficiency (EQE) measurement. In this study, we show how a low breakdown voltage of a component subcell impacts the EQE determination of a multijunction solar cell and demands the use of a finely adjusted external voltage bias. The optimum voltage bias for the EQE measurement of a Ge subcell in two different GaInP/GaInAs/Ge triple‐junction solar cells is determined both by sweeping the external voltage bias and by tracing the I–V curve under the same light bias conditions applied during the EQE measurement. It is shown that the I–V curve gives rapid and valuable information about the adequate light and voltage bias needed, and also helps to detect problems associated with non‐ideal I–V curves that might affect the EQE measurement. The results also show that, if a non‐optimum voltage bias is applied, a measurement artifact can result. Only when the problems associated with a non‐ideal I–V curve and/or a low breakdown voltage have been discarded, the measurement artifacts, if any, can be attributed to other effects such as luminescent coupling between subcells. Copyright © 2015 John Wiley & Sons, Ltd.
Is Science for Us? Black Students’ and Parents’ Views of Science and Science Careers
Authors: ARCHER LOUISE , DEWITT JENNIFER , OSBORNE JONATHAN
Published: February 2015

There are widespread policy concerns to improve (widen and increase) science, technology, engineering, and mathematics participation, which remains stratified by ethnicity, gender, and social class. Despite being interested in and highly valuing science, Black students tend to express limited aspirations to careers in science and remain underrepresented in post‐16 science courses and careers, a pattern which is not solely explained by attainment. This paper draws on survey data from nationally representative student cohorts and longitudinal interview data collected over 4 years from 10 Black African/Caribbean students and their parents, who were tracked from age 10–14 (Y6–Y9), as part of a larger study on children's science and career aspirations. The paper uses an intersectional analysis of the qualitative data to examine why science careers are less “thinkable” for Black students. A case study is also presented of two young Black women who “bucked the trend” and aspired to science careers. The paper concludes with implications for science education policy and practice.
Construction of resilient Boolean functions with high nonlinearity and good algebraic degree
Authors: Li Lu‐Yang , Zhang Wei‐Guo
Published: February 2015

Resilient Boolean functions with high nonlinearity and good algebraic properties play an important role in designing certain stream cipher schemes. In this paper, two construction methods are proposed to obtain such functions. It is shown that a class of resilient functions with high algebraic degree and currently best known nonlinearity can be constructed by using our technique. The algebraic immunity of the constructed functions is also analyzed. Copyright © 2015 John Wiley & Sons, Ltd.
Adipogenic Differentiation of hMSCs is Mediated by Recruitment of IGF-1r Onto the Primary Cilium Associated With Cilia Elongation
Authors: Dalbay Melis T. , Thorpe Stephen D. , Connelly John T. , Chapple J. Paul , Knight Martin M.
Published: February 2015

Primary cilia are single non-motile organelles that provide a highly regulated compartment into which specific proteins are trafficked as a critical part of various signaling pathways. The absence of primary cilia has been shown to prevent differentiation of human mesenchymal stem cells (hMSCs). Changes in primary cilia length are crucial for regulating signaling events; however it is not known how alterations in cilia structure relate to differentiation. This study tested the hypothesis that changes in primary cilia structure are required for stem cell differentiation. hMSCs expressed primary cilia that were labeled with acetylated alpha tubulin and visualized by confocal microscopy. Chemically induced differentiation resulted in lineage specific changes in cilia length and prevalence which were independent of cell cycle. In particular, adipogenic differentiation resulted in cilia elongation associated with the presence of dexamethasone, while insulin had an inhibitory effect on cilia length. Over a 7-day time course, adipogenic differentiation media resulted in cilia elongation within 2 days followed by increased nuclear PPARγ levels; an early marker of adipogenesis. Cilia elongation was associated with increased trafficking of insulin-like growth factor-1 receptor β (IGF-1Rβ) into the cilium. This was reversed on inhibition of elongation by IFT-88 siRNA transfection, which also decreased nuclear PPARγ. This is the first study to show that adipogenic differentiation requires primary cilia elongation associated with the recruitment of IGF-1Rβ onto the cilium. This study may lead to the development of cilia-targeted therapies for controlling adipogenic differentiation and associated conditions such as obesity. Stem Cells  2015;33:1952–1961
Effect of small axial force on flexural ductility design of high‐strength concrete beams
Authors: Bai Z. Z. , Au F. T. K. , Chen X. C.
Published: February 2015

Small axial forces may appear in beams in a reinforced concrete (RC) structure. The presence of compressive axial force, even at a low level, has an adverse effect on the flexural ductility of RC beams, which is a key attribute for seismic design. For example, Eurocode EN1998‐1 explicitly specifies such minimum flexural ductility, whereas Chinese code GB50011 limits the depth of equivalent rectangular stress block at peak resisting moment to achieve indirectly a certain nominal flexural ductility. Therefore, ignoring the presence of compressive axial force may be risky. In this study, the effect of small compressive axial force on the flexural ductility performance of both normal‐strength and high‐strength concrete beams is evaluated on the basis of a rigorous full‐range moment–curvature analysis. An effective strategy for flexural ductility design of RC beams with small compressive axial force is identified so that various flexural ductility requirements can be satisfied. The essential control parameter proposed is the maximum difference of tension and compression reinforcement ratios. Empirical formulae and tables are developed for convenient implementation. Copyright © 2015 John Wiley & Sons, Ltd.
Insight into conformational modification of alpha‐synuclein in the presence of neuronal whole cells and of their isolated membranes
Authors: Smaldone Giovanni , Diana Donatella , Pollegioni Loredano , Di Gaetano Sonia , Fattorusso Roberto , Pedone Emilia
Published: February 2015

A change in the conformational plasticity of α‐Synuclein (α‐Syn) is hypothesised to be a key step in the pathogenic mechanism of Parkinson's disease (PD). Here, we report the study of extracellular α‐Syn interaction with whole cells and membranes isolated from the neuronal SH‐SY5Y cells, exploiting NMR and CD spectroscopies. In addition, the crosslinking agent DSG was used to freeze the conformational and oligomeric state of α‐Syn in the presence of cells. These data, in a quasi‐physiological environment, confirm the protein monomeric state with a propensity to adopt a transient alpha helical following interaction with biological membranes.
Central Venous Catheter Securement: Using the Healthcare and Technology Synergy Model to Take a Closer Look
Authors: Macklin Denise , Blackburn Paul L.
Published: February 2015

Proper securement provides a safe vascular access device environment for both patients and health care providers. Successful securement protects central venous catheters from several sources of failure until the end of therapy by preventing central venous catheter movement during all phases of care. Movement causes vein trauma, bacterial migration, distal tip location variation, loss of dressing integrity, and even total dislodgement. Any of these events can have serious consequences, including catheter-related bloodstream infection, thrombosis, delay of treatment, catheter replacement, and potential hemorrhage, all of which can be life-threatening events, and increase costs. We review patient issues, practice issues, and the types of securement currently used in clinical settings.
Ultrasound-Guided Arm Ports: Indications, Techniques, and Management
Authors: Marcy Pierre Yves , Lacout Alexis , Thariat Juliette , Figl Andrea , Merckx Jacques
Published: February 2015

Purpose: Various venous access devices are available, including peripheral venous lines, peripherally inserted central catheters lines, and subcutaneous port catheters. The latter provides medium-to long-term venous access and includes medical devices that can be inserted either on the chest (chest ports) or in the arm (arm ports). We report the techniques, dedicated indications, and main complications of arm port insertion using the ultrasonography (US) guidance method.

Methods: Tips and tricks of percutaneous real-time US-guided vein access technique in the arm are reviewed, and a brief literature review is reported.

Results: Technical feasibility is almost 99%. US guidance allows depiction of anatomic variants, reduces the number of failed attempts, and increases the technical access rate compared with venography-guided access. Comparison of arm ports to chest ports reveals a higher global complication rate. We also report typical (mechanical) complications and dedicated indications, including contraindications to chest port insertion and selected patients for whom chest ports are not possible (eg, those with breast, head, and neck cancer; obesity; cosmesis; and requiring upright position).

Conclusions: Arm port insertion under US guidance is safe and effective, and has dedicated indications.
Nicolae Ceauşescu and the origins of Eurocommunism
Authors: Stanciu Cezar
Published: February 2015

After the Sino-Soviet dispute had considerably weakened Moscow’s supremacy in world communism, Soviet leader Leonid Brezhnev was keen on restoring control and unity. But he soon discovered that his meaning of unity did not exactly coincide with what others had in mind. West European communists were striving to accommodate social principles to domestic conditions so, as to be able to accede to government. They advocated for each party’s right to make their own decisions independently and also for an enlargement of world communism beyond its initial sectarianism. Their cause was vulnerable though as internationalism was still an important part of their political identity, apart from the fact that Moscow did subsidize most of them. In the second half of the 1960s though, a new voice joined those asking for reform in world communism: Nicolae Ceauşescu, a leader of the Romanian Communist Party. Interested to promote his country’s autonomy in the Soviet bloc, Ceauşescu had no reason to support Moscow’s efforts to regain control. Instead, Ceauşescu developed close relations with West European Communist parties and assumed some of their ideological tenets, trying to fend off Soviet domination. This way, although he never was a Eurocommunist, Ceauşescu did play an important part in the ideological debates that were later to produce Eurocommunism, defendingWest European arguments in front of Moscow.
Kraichnan–Leith–Batchelor similarity theory and two-dimensional inverse cascades
Authors: Burgess B. H. , Scott R. K. , Shepherd T. G.
Published: February 2015

We study the scaling properties and Kraichnan–Leith–Batchelor (KLB) theory of forced inverse cascades in generalized two-dimensional (2D) fluids (${\it\alpha}$-turbulence models) simulated at resolution $8192^{2}$. We consider ${\it\alpha}=1$ (surface quasigeostrophic flow), ${\it\alpha}=2$ (2D Euler flow) and ${\it\alpha}=3$. The forcing scale is well resolved, a direct cascade is present and there is no large-scale dissipation. Coherent vortices spanning a range of sizes, most larger than the forcing scale, are present for both ${\it\alpha}=1$ and ${\it\alpha}=2$. The active scalar field for ${\it\alpha}=3$ contains comparatively few and small vortices. The energy spectral slopes in the inverse cascade are steeper than the KLB prediction $-(7-{\it\alpha})/3$ in all three systems. Since we stop the simulations well before the cascades have reached the domain scale, vortex formation and spectral steepening are not due to condensation effects; nor are they caused by large-scale dissipation, which is absent. One- and two-point p.d.f.s, hyperflatness factors and structure functions indicate that the inverse cascades are intermittent and non-Gaussian over much of the inertial range for ${\it\alpha}=1$ and ${\it\alpha}=2$, while the ${\it\alpha}=3$ inverse cascade is much closer to Gaussian and non-intermittent. For ${\it\alpha}=3$ the steep spectrum is close to that associated with enstrophy equipartition. Continuous wavelet analysis shows approximate KLB scaling $\mathscr{E}(k)\propto k^{-2}~({\it\alpha}=1)$ and $\mathscr{E}(k)\propto k^{-5/3}~({\it\alpha}=2)$ in the interstitial regions between the coherent vortices. Our results demonstrate that coherent vortex formation (${\it\alpha}=1$ and ${\it\alpha}=2$) and non-realizability (${\it\alpha}=3$) cause 2D inverse cascades to deviate from the KLB predictions, but that the flow between the vortices exhibits KLB scaling and non-intermittent statistics for ${\it\alpha}=1$ and ${\it\alpha}=2$.
Effect of feeding butoxybutyl alcohol on the growth performance and status of skeletal muscle proteolysis in broiler chickens
Authors: KAMIZONO T. , SAPUTRA D. , MIURA I. , KIKUSATO M. , HAYASHI K. , TOYOMIZU M.
Published: February 2015

Butoxybutyl alcohol (BBA) is a possible growth promoter contained in the fermentation and distillation by-products of a traditional Japanese spirit, shochu. In the present study, BBA was synthesized and its chemical structure was confirmed by gas chromatography mass spectrometry and nuclear magnetic resonance. Then, two studies were conducted to investigate the effects of feeding the synthesized BBA on the growth and skeletal muscle proteolysis of broiler chickens. Ross male broiler chickens were divided into two groups, control (basal diet: 219 g crude protein/kg and 12·66 MJ metabolizable energy/kg) and BBA diet (30 mg BBA/kg basal diet), with the experimental diets being provided from 15 to 27 days and 0 to 27 days of age, for Studies 1 and 2, respectively. Butoxybutyl alcohol supplementation increased final body weight in both studies, whereas feed intake was unchanged, thereby indicating significantly increased feed efficiency. Furthermore, the synthesized BBA increased the weights of the pectoralis superficialis and profundus muscles, and the leg. The BBA decreased theNτ-methylhistidine concentration in the excrement and plasma, which are indices of the rate of skeletal muscle protein degradation. It also decreased the mRNA levels of μ-calpain large subunit, atrogin-1/muscle atrophy F-box (MAFbx), ubiquitin and 20S proteasome C2 subunit. These suggest that growth promotion due to the feeding of synthesized BBA is caused by the suppression of skeletal muscle protein degradation, which is related to a decrease in gene expression in the calpain and ubiquitin–proteasome systems.