bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic sensitivity analysis for timing and amplitude of pressure waves in the arterial system
Authors: Eck V. G. , Feinberg J. , Langtangen H. P. , Hellevik L. R.
Published: February 2015

In the field of computational hemodynamics, sensitivity quantification of pressure and flow wave dynamics has received little attention. This work presents a novel study of the sensitivity of pressure‐wave timing and amplitude in the arterial system with respect to arterial stiffness. Arterial pressure and flow waves were simulated with a one‐dimensional distributed wave propagation model for compliant arterial networks. Sensitivity analysis of this model was based on a generalized polynomial chaos expansion evaluated by a stochastic collocation method. First‐order statistical sensitivity indices were formulated to assess the effect of arterial stiffening on timing and amplitude of the pressure wave and backward‐propagating pressure wave in the ascending aorta, at the maximum pressure and inflection point in the systolic phase. Only the stiffness of aortic arteries was found to significantly influence timing and amplitude of the backward‐propagating pressure wave, whereas other large arteries in the systemic tree showed marginal impact. Furthermore, the ascending aorta, aortic arch, thoracic aorta, and infrarenal abdominal aorta had the largest influence on amplitude, whereas only the thoracic aorta influenced timing. Our results showed that the non‐intrusive polynomial chaos expansion is an efficient method to compute statistical sensitivity measures for wave propagation models. These sensitivities provide new knowledge in the relative importance of arterial stiffness at various locations in the arterial network. Moreover, they will significantly influence clinical data collection and effective composition of the arterial tree for in‐silico clinical studies. Copyright © 2015 John Wiley & Sons, Ltd.
Should the Woodward–Hoffmann Rules be Applied to Mechanochemical Reactions?
Authors: Wollenhaupt Miriam , Krupička Martin , Marx Dominik
Published: February 2015

Since decades, pericyclic reactions have been well‐understood by means of the Woodward–Hoffmann rules and their classification as thermally or photochemically “allowed” or “forbidden”. Recently, stunning results on such reactions subject to mechanochemical activation by external forces instead of heat or light have revealed reaction pathways at sufficiently large forces, which are not expected from the Woodward–Hoffmann rules. This led to the much reiterated idea that the “Woodward–Hoffmann rules are broken in mechanochemistry”. Here, by studying ring‐opening of cyclopropane, we show that the electronic structure underlying the dis‐ and conrotatory pathways, which are greatly distorted upon applying forces to an extent that eventually the “thermally forbidden” process becomes “mechanochemically allowed”, does not change along both pathways. It is rather the mechanical work that lowers the activation barrier of the thermally forbidden conrotatory process relative to the disrotatory one at large forces.
Symbolic factorization methodology for multistage amplifier transfer functions
Authors: Grasso A. D. , Marano D. , Pennisi S. , Vazzana G.
Published: February 2015

In this paper, we discuss a symbolic simplification methodology to derive approximated factorized forms of the transfer function of multistage amplifiers in the complex frequency domain. The developed approach is useful for hand calculation and is also suitable to be implemented in symbolic computer‐aided design tools. Although the proposed methodology is mainly intended for the analysis and design of operational transconductance amplifiers, it can straightforwardly be applied to the small‐signal analysis of any analog linear circuit. Design examples are provided to verify the effectiveness of the proposed approach implemented through a Matlab function. Copyright © 2015 John Wiley & Sons, Ltd.
Limit liability related to students with disabilities in fraternity, sorority houses
Authors: McCarthy Claudine
Published: February 2015

There's much you can do to limit your institution's liability related to providing accommodations and ensuring accessibility for students living in fraternity and sorority housing. That's according to Laura Rothstein, University of Louisville law professor; and Beth Stathos, general counsel for Chi Omega Fraternity in Memphis, Tenn. They spoke at Stetson University's last National Conference on Law & Higher Education.
Deaf student wins preliminary injunction after medical school admits, then rejects him
Authors: Charmatz Marc
Published: February 2015

An institution that accepts a student with a disability, delays in honoring his requests for auxiliary aids, and then withdraws his admission does so at its own peril, as the Pacific Northwest University of Health Sciences found out. The institution admitted and then rejected Zachary Featherstone's application for admission to medical school, and he subsequently sued.
Develop collaborative support model to boost employment opportunities for students on spectrum
Authors: Meeks Lisa , Westlake Garret
Published: February 2015

Individuals with autism spectrum disorder are attending college in record numbers. Unfortunately, completing a college degree does not appear to improve employment outcomes for individuals with ASD, and many find it difficult to both acquire and retain jobs.
Structural Relationship between the Mg‐Containing Nitridosilicates Ca2Mg[Li4Si2N6] and Li2Ca2[Mg2Si2N6]
Authors: Schmiechen Sebastian , Nietschke Frederik , Schnick Wolfgang
Published: February 2015

Ca2Mg[Li4Si2N6] and Li2Ca2[Mg2Si2N6] were synthesized in sealed tantalum ampules with Li as a fluxing agent. Both compounds crystallize in the monoclinic space group C2/m (no. 12). The crystal structures were solved and refined on the basis of single‐crystal X‐ray diffraction data [Z = 2; Ca2Mg[Li4Si2N6]: a = 5.9059(12), b = 9.817(2), c = 5.6109(11) Å, β = 94.90(3)°, R1 = 0.015, wR2 = 0.049; Li2Ca2[Mg2Si2N6]: a = 5.5472(11), b = 9.844(2), c = 5.9978(12) Å, β = 97.13(3)°, R1 = 0.024, wR2 = 0.053]. Ca2Mg[Li4Si2N6] is isomorphic to Ca3[Li4Si2N6] and its crystal structure is homeotypic to that of Li2Ca2[Mg2Si2N6]. Both structures are built up of edge‐sharing [Si2N6]10– tetrahedra (bow‐tie units). In the nitridolithosilicate Ca2Mg[Li4Si2N6] the bow‐tie units are connected via pairs of LiN4 tetrahedra, whereas in the nitridomagnesosilicate Li2Ca2[Mg2Si2N6] the nitridosilicate substructure is connected by chains of MgN4 tetrahedra. Ca2Mg[Li4Si2N6] is only the second example of fourfold planar rectangular coordinated Mg2+ in a nitridosilicate. Li2Ca2[Mg2Si2N6] is the first nitridosilicate with Li+ in threefold coordination. The crystal structures were confirmed by lattice‐energy calculations (MAPLE), EDX measurements, and powder X‐ray diffraction.
Osmium–Nitrosyl Oxalato‐Bridged Lanthanide‐Centered Pentanuclear Complexes – Synthesis, Crystal Structures and Magnetic Properties
Authors: Gavriluta Anatolie , Claiser Nicolas , Kuhn Paul‐Steffen , Novitchi Ghenadie , Tommasino Jean Bernard , Iasco Olga , Druta Vadim , Arion Vladimir B. , Luneau Dominique
Published: February 2015

A series of pentanuclear heterometallic coordination compounds of the general formula (Bu4N)5[Ln{Os(NO)(μ‐ox)Cl3}4(H2O)n] [Ln = Y (for 2) and Dy (for 3′) when n = 0; Ln = Dy (for 3), Tb (for 4), and Gd (for 5) when n = 1] were synthesized by the reaction of the precursor (Bu4N)2[Os(NO)(ox)Cl3] (1) with the respective lanthanide(III) (Gd, Tb, Dy) or yttrium(III) chloride. For the five new complexes, the coordination numbers eight or nine are found for the central metal ion. The compounds were fully characterized by elemental analysis, IR spectroscopy, single‐crystal X‐ray diffraction analysis, magnetic susceptibility measurements, and ESI mass spectrometry. In addition, compound 1 was studied by UV/Vis spectroscopy and cyclic voltammetry. The X‐ray diffraction analyses revealed that the anionic complexes consist of a lanthanide or yttrium core bridged through oxalato ligands to four octahedral osmium–nitrosyl moieties. This picture, in which the central ion is eight‐coordinate, holds for lanthanide ions with an ionic radius smaller than that of the dysprosium(III) ion. For larger ionic radii, the central metal ion is nine‐coordinate, as the coordination sphere is completed by one molecule of water. Only in the case of dysprosium(III), it was possible to obtain complexes with both coordination numbers 8 and 9. This implies that dysprosium(III) is the tilt limit between the two coordination numbers in this series. The bond length Ln–O decreases from Dy to Gd. The nine‐coordinate complexes are energetically more favored for lanthanide ions with a radius larger than that of the dysprosium(III) ion, and the eight‐coordinate complexes are favored for smaller ions. Magnetic studies of the series of compounds showed that the osmium precursor 1 as well as the yttrium compound 2 are diamagnetic, whereas the magnetism of the gadolinium, terbium, and dysprosium complexes is due to isolated lanthanide ions.
Bar dynamics and bifurcation evolution in a modelled braided sand‐bed river
Authors: Schuurman Filip , Kleinhans Maarten G.
Published: February 2015

Morphodynamics in sand‐bed braided rivers are associated with simultaneous evolution of mid‐channel bars and channels on the braidplain. Bifurcations around mid‐channel bars are key elements that divide discharge and sediment. This, in turn, may control the evolution of connected branches, with effects propagating to both upstream and downstream bifurcations. Recent works on bifurcation stability and development hypothesize major roles of secondary flow and gradient advantage. However, this has not been tested for channel networks within a fully developed dynamic braided river. A reason for this is a lack of detailed measurements with sufficient temporal and spatial length, covering multiple bifurcations. Therefore we used a physics‐based numerical model to generate a dataset of bathymetry, flow and sediment transport of an 80 km river reach with self‐formed braid bars and bifurcations. The study shows that bar dissection due to local transverse water surface gradients is the dominant bifurcation initiation mechanism, although conversion of unit bars into compound bars dominates in the initial stage of a braided river. Several bifurcation closure mechanisms are equally important. Furthermore, the study showed that nodal point relations for bifurcations are unable to predict short‐term bifurcation evolution in a braided river. This is explained by occurrence of nonlinear processes and non‐uniformity within the branches, in particular migrating bars and larger‐scale backwater‐effects, which are not included in the nodal point relations. Planform morphology, on the other hand, has predictive capacity: bifurcation angle asymmetry and bar‐tail limb shape are indicators for near‐future bifurcation evolution. Remote sensing data has predictive value, for which we developed a conceptual model for interactions between bars, bifurcations and channels in the network. We conducted a preliminary test of the conceptual model on satellite images of the Brahmaputra. Copyright © 2015 John Wiley & Sons, Ltd.
Long- and short-term effects of smothering and burial by drill cuttings on calcareous algae in a static-renewal test
Authors: Reynier Márcia V. , Tâmega Frederico T. S. , Daflon Sarah D. A. , Santos Maurício A. B. , Coutinho Ricardo , Figueiredo Marcia A. O.
Published: February 2015

Discharge of drill cuttings into the ocean during drilling of offshore oil wells can impact benthic communities through an increase in the concentrations of suspended particles in the water column and sedimentation of particles on the seafloor around the drilling installation. The present study assessed effects of water-based drill cuttings, barite, bentonite, and natural sediments on shallow- and deep-water calcareous algae in short-term (30 d) and long-term (90 d) experiments, using 2 species from Peregrino's oil field at Campos Basin, Brazil: Mesophyllum engelhartii and Lithothamnion sp. The results were compared with the shallow-water species Lithothamnion crispatum. Smothering and burial exposures were simulated. Oxygen production and fluorescence readings were recorded. Although less productive, M. engelhartii was as sensitive to stress as Lithothamnion sp. Mesophyllum engelhartii was sensitive to smothering by drill cuttings, barite, and bentonite after 60 d of exposure and was similarly affected by natural sediments after 90 d. These results indicate that smothering by sediments caused physical effects that might be attributable to partial light attenuation and partial restriction on gas exchange but did not kill the calcareous algae in the long term. However, 1-mo burial by either natural sediments or drill cuttings was sufficient after 60 d for both species to reduce oxygen production, and the algae were completely dead under both sources of sediments. Environ Toxicol Chem 2015;34:1572–1577. © 2015 SETAC
An HPLC method for hydroperoxides derived from limonene and linalool in citrus oils, using post‐column luminol‐mediated chemiluminescence detection
Authors: Calandra Michael J. , Impellizzeri John , Wang Ying
Published: February 2015

Limonene and linalool are unsaturated terpenes commonly found as major components in many essential oils, and both are easily oxidized by atmospheric oxygen to form hydroperoxides. The hydroperoxides of both limonene and linalool are known to be sensitizers capable of causing allergic contact dermatitis, but with different potency. In addition, positional isomers of limonene hydroperoxide have been demonstrated to have different allergenic potencies. This creates a need for an analytical method that is capable of differentiating hydroperoxides derived from different terpenes, including the various positional isomers. The standard iodometric titration methods [peroxide value (POV) methods] typically used to measure hydroperoxide levels in essential oils provide only a total level of all oxidizing species, including hydroperoxides. These POV methods are not capable of species differentiation and therefore may not reliably correlate well with the skin sensitizing potency of a particular sample. A high‐performance liquid chromatographic (HPLC) method using a post‐column reaction to produce chemiluminescence via luminol oxidation was developed to address the need for a species‐differentiating method. Copyright © 2015 John Wiley & Sons, Ltd.
Should Cost‐Effectiveness Analysis Include the Cost of Consumption Activities? AN Empirical Investigation
Authors: Adarkwah Charles Christian , Sadoghi Amirhossein , Gandjour Afschin
Published: February 2015

There has been a debate on whether cost‐effectiveness analysis should consider the cost of consumption and leisure time activities when using the quality‐adjusted life year as a measure of health outcome under a societal perspective. The purpose of this study was to investigate whether the effects of ill health on consumptive activities are spontaneously considered in a health state valuation exercise and how much this matters.

The survey enrolled patients with inflammatory bowel disease in Germany (n = 104). Patients were randomized to explicit and no explicit instruction for the consideration of consumption and leisure effects in a time trade‐off (TTO) exercise.

Explicit instruction to consider non‐health‐related utility in TTO exercises did not influence TTO scores. However, spontaneous consideration of non‐health‐related utility in patients without explicit instruction (60% of respondents) led to significantly lower TTO scores.

Results suggest an inclusion of consumption costs in the numerator of the cost‐effectiveness ratio, at least for those respondents who spontaneously consider non‐health‐related utility from treatment. Results also suggest that exercises eliciting health valuations from the general public may include a description of the impact of disease on consumptive activities. Copyright © 2015 John Wiley & Sons, Ltd.
Nothing About Us Without Us? A Comparison of Adolescent and Adult Health‐State Values for the Child Health Utility‐9D Using Profile Case Best–Worst Scaling
Authors: Ratcliffe Julie , Huynh Elisabeth , Stevens Katherine , Brazier John , Sawyer Michael , Flynn Terry
Published: February 2015

The main objective of this study was to compare and contrast adolescent and adult values for the Child Health Utility‐9D (CHU9D), a new generic preference‐based measure of health‐related quality of life designed for application in the economic evaluation of treatment and preventive programmes for children and adolescents. Previous studies have indicated that there may be systematic differences in adolescent and adult values for identical health states. An online survey including a series of best–worst scaling discrete choice experiment questions for health states defined by the CHU9D was administered to two general population samples comprising adults and adolescents, respectively. The results highlight potentially important age‐related differences in the values attached to CHU9D dimensions. Adults, in general, placed less weight upon impairments in mental health (worried, sad, annoyed) and more weight upon moderate to severe levels of pain relative to adolescents. The source of values (adults or adolescents) has important implications for economic evaluation and may impact significantly upon healthcare policy. Copyright © 2015 John Wiley & Sons, Ltd.
Toward a standard lexicon for ecosystem services
Authors: Munns Wayne R , Rea Anne W , Mazzotta Marisa J , Wainger Lisa A , Saterson Kathryn
Published: February 2015

The complex, widely dispersed, and cumulative environmental challenges currently facing society require holistic, transdisciplinary approaches to resolve. The concept of ecosystem services (ES) has become more widely accepted as a framework that fosters a broader systems perspective of sustainability and can make science more responsive to the needs of decision makers and the public. Successful transdisciplinary approaches require a common language and understanding of key concepts. Our primary objective is to encourage the ES research and policy communities to standardize terminology and definitions, to facilitate mutual understanding by multidisciplinary researchers and policy makers. As an important step toward standardization, we present a lexicon developed to inform ES research conducted by the US Environmental Protection Agency and its partners. We describe a straightforward conceptualization of the relationships among environmental decisions, their effects on ecological systems and the services they provide, and human well-being. This provides a framework for common understanding and use of ES terminology. We encourage challenges to these definitions and attempts to advance standardization of a lexicon in ways that might be more meaningful to our ultimate objective: informing environmental decisions in ways that promote the sustainability of the environment upon which we all depend. Integr Environ Assess Manag 2015;9999:XX–XX. Published 2015 SETAC. This article is a US Government work and, as such, is in the public domain in the USA.

Key Points

Issues of sustainability require holistic, transdisciplinary approaches to resolve. The ecosystem services concept-characterized by a broader systems perspective of sustainability-can help science to inform decision making. Lack of standard terminology hinders scientific progress and its policy application. We offer a standard lexicon of ecosystem service terminology, which can promote scientific advancement and application to policy and management.
TSLP is differentially regulated by vitamin D3 and cytokines in human skin
Authors: Landheer Janneke , Giovannone Barbara , Sadekova Svetlana , Tjabringa Sandra , Hofstra Claudia , Dechering Koen , Bruijnzeel‐Koomen Carla , Chang Charlie , Ying Yu , de Waal Malefyt Rene , Hijnen DirkJan , Knol Edward
Published: February 2015

Thymic stromal lymphopoietin (TSLP) plays an important role in allergic diseases and is highly expressed in keratinocytes in human lesional atopic dermatitis (AD) skin. In nonlesional AD skin TSLP expression can be induced by applying house dust mite allergen onto the skin in the atopy patch test. Several studies have demonstrated that the induction of TSLP expression in mouse skin does not only lead to AD‐like inflammation of the skin, but also predisposes to severe inflammation of the airways. In mice, TSLP expression can be induced by application of the 1,25‐dihydroxyvitamin D3 (VD3) analogue calcipotriol and results in the development of eczema‐like lesions. The objective is to investigate the effect of VD3 (calcitriol) or calcipotriol on TSLP expression in normal human skin and skin from AD patients. Using multiple ex vivo experimental setups, the effects of calci(po)triol on TSLP expression by normal human skin, and skin from AD patients were investigated and compared to effects of calcipotriol on mouse and non‐human primates (NHP) skin. No induction of TSLP expression (mRNA or protein) was observed in human keratinocytes, normal human skin, nonlesional AD skin, or NHP skin samples after stimulation with calcipotriol or topical application of calcitriol. The biological activity of calci(po)triol in human skin samples was demonstrated by the increased expression of the VD3‐responsive Cyp24a1 gene. TSLP expression was induced by cytokines (IL‐4, IL‐13, and TNF‐α) in skin samples from all three species. In contrast to the findings in human and NHP, a consistent increase in TSLP expression was confirmed in mouse skin biopsies after stimulation with calcipotriol. VD3 failed to induce expression of TSLP in human or monkey skin in contrast to mouse, implicating careful extrapolation of this often‐used mouse model to AD patients.
Intravascular magnetomotive optical coherence tomography of targeted early‐stage atherosclerotic changes in ex vivo hyperlipidemic rabbit aortas
Authors: Kim Jongsik , Ahmad Adeel , Li Joanne , Marjanovic Marina , Chaney Eric J. , Suslick Kenneth S. , Boppart Stephen A.
Published: February 2015

We report the development of an intravascular magnetomotive optical coherence tomography (IV‐MM‐OCT) system used with targeted protein microspheres to detect early‐stage atherosclerotic fatty streaks/plaques. Magnetic microspheres (MSs) were injected in vivo in rabbits, and after 30 minutes of in vivo circulation, excised ex vivo rabbit aorta samples specimens were then imaged ex vivo with our prototype IV‐MM‐OCT system. The alternating magnetic field gradient was provided by a unique pair of external custom‐built electromagnetic coils that modulated the targeted magnetic MSs. The results showed a statistically significant MM‐OCT signal from the aorta samples specimens injected with targeted MSs.

Representative magnetomotive signal (green) using targeted and non‐targeted magnetomotive microspheres in atherosclerotic diseased rabbit aortas.

magnified image

Representative magnetomotive signal (green) using targeted and non‐targeted magnetomotive microspheres in atherosclerotic diseased rabbit aortas.
Deformation of single‐walled carbon nanotubes by interaction with graphene: A first‐principles study
Authors: Wang Xiao , Yang Juan , Li Ruoming , Jiang Hong , Li Yan
Published: February 2015

The interaction between single‐walled carbon nanotubes (SWNTs) and graphene were studied with first‐principles calculations. Both SWNTs and single‐layer graphene (SLG) or double‐layer graphene (DLG) display more remarkable deformations with the increase of SWNT diameter, which implies a stronger interaction between SWNTs and graphene. Besides, in DLG, deformation of the upper‐layer graphene is less than in SLG. Zigzag SWNTs show stronger interactions with SLG than armchair SWNTs, whereas the order is reversed for DLG, which can be interpreted by the mechanical properties of SWNTs and graphene. Density of states and band structures were also studied, and it was found that the interaction between a SWNT and graphene is not strong enough to bring about obvious influence on the electronic structures of SWNTs. © 2015 Wiley Periodicals, Inc.
Biotherapy of pancreatic neuroendocrine tumors using somatostatin analogs
Authors: Igarashi Hisato , Hijioka Masayuki , Lee Lingaku , Ito Tetsuhide
Published: February 2015

Basically, pancreatic neuroendocrine tumor (PNET) should be treated surgically; however, in unresectable cases, a treatment that aims to improve the prognosis by inhibiting the growth of the tumor and control the clinical symptoms becomes necessary. In the case of functional tumors, the quality of life of patients is decreased by not only the symptoms with tumor invasion and/or metastasis but also by the symptoms of hormone excess. The efficacy of somatostatin analogs against the latter has been previously reported, and their sustained release formulations have been developed. Somatostatin analogs are recommended to treat the endocrine symptoms of functional PNET; however, in case they can cause hypoglycemia in patients with insulinoma. On the other hand, results from the PROMID study demonstrated a tumor‐stabilizing effect when octreotide LAR (long acting repeatable) was used to treat patients with advanced midgut NET; however, there has been no consensus regarding its antitumor effect for PNET. Additionally, a recent result from the CLARINET study suggests that lanreotide autogel has an antitumor effect against nonfunctional NET including PNET. Further clinical study results are awaited.
Synthesis and Biological Activity of Ethyl 4‐Alkyl‐2‐(2‐(substituted phenoxy)acetamido)thiazole‐5‐carboxylate
Authors: Mo Wenyan , Shi Yanxia , He Junbo , Li Baoju , Peng Hao , He Hongwu
Published: February 2015

A series of novel ethyl 4‐(methyl or trifluoromethyl)‐2‐(2‐(substituted phenoxy)acetamido)thiazole‐5‐carboxylates 7a, 7b, 7c, 7d, 7e and 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n, 8o, 8p, 8q, 8r were synthesized, and their structures were confirmed by IR, 1H‐NMR, MS spectra and elemental analysis. The results of preliminary bioassays show that some of the title compounds exhibit moderate to good herbicidal activities. Compared with the fluorine free compounds 7a, 7b, and 7e, the compounds bearing fluorine 8g, 8j, and 8q showed higher herbicidal activities with 70–100% inhibition against Capsella bursa‐pastoris, Amaranthus restroflexus, and Eclipta prostrata at the dosage of 150 g/ha, which indicated that the trifluoromethyl on the thiazole ring was beneficial for the herbicidal activity. Furthermore, compounds 8f, 8g, 8h, 8i, 8j, 8k, 8l, 8m, 8n, 8o, 8p, 8q, 8r were tested for fungicidal activity against Pseudoperonospora cubensis at 500 µg/mL. Compounds 8f and 8q showed the best fungicidal activity with more than 80% inhibition.
MR evaluation of vessel size imaging of human gliomas: Validation by histopathology
Authors: Kellner Elias , Breyer Tobias , Gall Peter , Müller Klaus , Trippel Michael , Staszewski Ori , Stein Florian , Saborowski Olaf , Dyakova Olga , Urbach Horst , Kiselev Valerij G , Mader Irina
Published: February 2015

Purpose

To compare the vessel size and the cerebral blood volume in human gliomas with histopathology. Vessel size imaging (VSI) is a dynamic susceptibility contrast method for the assessment of the vessel size in normal and pathological tissue. Previous publications in rodents showed a satisfactory conformity with the vessel size derived from histopathology. To assess the clinical value, further, the progression‐free interval was determined and correlated.

Materials and Methods

Twenty‐five gliomas (WHO grade °II [n = 10], °III [n = 3], °IV [n = 12]) were prospectively included and received a stereotaxic biopsy after VSI. The vessel size and the cerebral blood volume (CBV) were calculated in regions of interest at the tumor edge and correlated with the vessel size measured by histopathology.

Results

Both VSI and CBV showed a good correlation with the vessel size in histopathology (up to r = 0.84, P < 0.001, and r = 0.62, P < 0.001, respectively). Slope and offset of the linear regression (y = 0.77x + 0.36 μm) suggest that the size of normal capillaries is overestimated with VSI, while for grossly enlarged vessels an underestimation occurs. Both VSI and CBV were negatively correlated with the progression‐free interval (r = –0.57, P = 0.008, and r = –0.50, P = 0.025, respectively).

Conclusion

The correlation between VSI and vessel size from histopathology is in good accordance with the animal studies. The overestimation of small capillary sizes is also known from the animal trials. Vessel size and CBV showed similar results, both for the correlation with the histopathological vessel size and the progression‐free interval. J. Magn. Reson. Imaging 2015;42:1117–1125.
Purification, characterization, and gene cloning of a chitinase from Stenotrophomonas maltophilia N4
Authors: Jankiewicz Urszula , Brzezinska Maria Swiontek
Published: February 2015

The Stenotrophomonas maltophilia synthesises high‐activity chitinase in response to chitin or chitosan induction. The enzyme was purified 8.5 fold and subjected to characterisation. The optimum hydrolysis conditions for this enzyme when using colloidal chitin as substrate were pH 5.6 and temperature of 45 °C. The enzyme demonstrated high thermal stability at 45 °C within 2 h. The studied chitinase exhibited high activity towards colloidal chitin, glycol chitin and chitosan, while it did not hydrolyse glycosidic bonds in carboxymethylcellulose. The enzyme exhibited the highest activity, equalling 90 U/ml, towards Nitrophenyl β‐D‐N,N′,N″‐triacetylchitotriose and activity of 37 U/ml towards 4‐Nitrophenyl N,N′‐diacetyl‐β‐D‐chitobioside. The Km value in the presence of the two former substrates was:1.2 and 3.9 mM, respectively, which classifies the studied enzyme as an endochitinase. Cysteine and 2‐mercaptoethanol stimulated to a small degree the activity of the chitinase which may indicate the involvement of cysteine residues in the catalysis mechanism. The full length of the nucleotide sequence of this chitinase gene is 2106 bp, which amounts to 702 amino acids.
Characterization of the native form and the carboxy‐terminally truncated halotolerant form of α‐amylases from Bacillus subtilis strain FP‐133
Authors: Takenaka Shinji , Miyatake Ayaka , Tanaka Kosei , Kuntiya Ampin , Techapun Charin , Leksawasdi Noppol , Seesuriyachan Phisit , Chaiyaso Thanongsak , Watanabe Masanori , Yoshida Ken‐ichi
Published: February 2015

Two amylases, amylase I and amylase II from Bacillus subtilis strain FP‐133, were purified to homogeneity and characterized. Their stabilities toward temperature, pH, and organic solvents, and their substrate specificities toward polysaccharides and oligosaccharides were similar. Under moderately high salt conditions, both amylases were more stable than commercial B. licheniformis amylase, and amylase I retained higher amylase activity than amylase II. The N‐terminal amino acid sequence, genomic southern blot analysis, and MALDI‐TOFF‐MS analysis indicated that the halotolerant amylase I was produced by limited carboxy‐terminal truncation of the amylase II peptide. The deduced amino acid sequence of amylase II was >95% identical to that of previously reported B. subtilis α‐amylases, but their carboxy‐terminal truncation points differed. Three recombinant amylases — full‐length amylase corresponding to amylase II, an artificially truncated amylase corresponding to amylase I, and an amylase with a larger artificial C‐terminal truncation — were expressed in B. subtilis. The artificially truncated recombinant amylases had the same high amylase activity as amylase I under moderately high salt conditions. Sequence comparisons indicated that an increased ratio of Asp/Glu residues in the enzyme may be one factor responsible for increasing halotolerance.
Mycotoxins – prevention and decontamination by yeasts
Authors: Pfliegler Walter P. , Pusztahelyi Tünde , Pócsi István
Published: February 2015

The application of yeasts has great potential in reducing the economic damage caused by toxigenic fungi in the agriculture. Some yeasts may act as biocontrol agents inhibiting the growth of filamentous fungi. These species may also gain importance in the preservation of agricultural products and in the reduction of their mycotoxin contamination, yet the extent of mycotoxin production in the presence of biocontrol agents is relatively less understood. The application of yeasts in various technological processes may have a direct inhibitory effect on the toxin production of certain molds, which is independent of their growth suppressing effect. Furthermore, several yeast species are capable of accumulating mycotoxins from agricultural products, thereby effectively decontaminating them. Probiotic yeasts or products containing yeast cell wall are also applied to counteract mycotoxicosis in livestock. Several yeast strains are also able to degrade toxins to less‐toxic or even non‐toxic substances. This intensively researched field would greatly benefit from a deeper knowledge on the genetic and molecular basis of toxin degradation. Moreover, yeasts and their biotechnologically important enzymes may exhibit sensitivity to certain mycotoxins, thereby mounting a considerable problem for the biotechnological industry. It is noted that yeasts are generally regarded as safe; however, there are reports of toxin degrading species that may cause human fungal infections. The aspects of yeast–mycotoxin relations with a brief consideration of strain improvement strategies and genetic modification for improved detoxifying properties and/or mycotoxin resistance are reviewed here.
Influence of the November Arctic Oscillation on the subsequent tropical Pacific sea surface temperature
Authors: Chen Shangfeng , Wu Renguang , Chen Wen , Yu Bin
Published: February 2015

Previous studies suggested that the variability of boreal spring Arctic Oscillation (AO) can exert a significant influence on the sea surface temperature (SST) anomalies in the Niño‐3.4 region during the following winter. This study further reveals that AO in November can have a pronounced influence on the tropical central‐eastern Pacific SST anomalies during the following spring and summer. When the November AO is in its positive (negative) phase, SST anomalies tend to be positive (negative) during the following spring and summer in the tropical central‐eastern Pacific. The influence of the AO is accomplished by atmospheric circulation anomalies over the subtropical North Pacific through an interaction between the synoptic‐scale eddy and the low‐frequency mean flow. In the positive November AO years, pronounced cyclonic circulation and atmospheric heating anomalies are observed over the subtropical North Pacific. The atmospheric heating anomalies sustain westerly wind anomalies over the tropical western North Pacific through a Gill‐like atmospheric response. The westerly wind anomalies extend eastward subsequently through positive air–sea feedback mechanism, and result in SST warming during the following spring and summer in the tropical central‐eastern Pacific. Results of this study imply that the November AO index can be used as an effective predictor of SST anomalies in the Niño‐3.4 region during the following spring and summer.
Research on the characteristics of urban rainstorm pattern in the humid area of Southern China: a case study of Guangzhou City
Authors: Chen Zhihe , Yin Lei , Chen Xiaohong , Wei Shuai , Zhu Zhihua
Published: February 2015

Extreme precipitation occurs frequently because of hydrological variability, resulting in humid cities facing serious waterlogging problems. Previous studies about rainstorms had emphasized on spatial–temporal distribution characteristics, but rarely on rainfall pattern (RP). With a typical humid city in southern China, such as Guangzhou City in Guangdong Province as the research object, hourly precipitation data from January 2009 to October 2014 are collected from five meteorological stations in Guangzhou. The data are counted and classified by fuzzy mode recognition method according to seven typical rainfall patterns (STRP) and the Huff rainfall pattern (Huff RP). Subsequently, the distributive characteristics of urban rainstorm pattern (RSP) are analyzed. The main results obtained are as follows: (1) annual rainstorm days have high positive correlation with rainfall days, and the annual amount of rainstorm contributes to 7.5–50.5% of the annual total rainfall in Guangzhou, (2) large‐scale rainfall is highly possible to occur in Guangzhou, (3) most rainstorms in Guangzhou are unimodal, of which the frontal peak is more than 70%, and (4) STRP are appropriate for RSP division in Guangzhou City.
Electrochemical properties of corrosion products formed on Zn‐Mg, Zn‐Al and Zn‐Al‐Mg coatings in model atmospheric conditions
Authors: Stoulil J. , Prosek T. , Nazarov A. , Oswald J. , Kriz P. , Thierry D.
Published: February 2015

The electrochemical properties of corrosion products formed under sodium chloride deposits on zinc coatings alloyed with aluminium and magnesium have been studied using impedance spectroscopy (EIS), scanning Kelvin probe (SKP) and photoluminescence (PL) techniques. The low‐energy band gap identified in corrosion products on hot‐dip galvanized steel was associated with their higher electric conductivity and efficiency of the rate‐controlling oxygen reduction reaction. It was attributed to the presence of ZnO, zincite. The formation of ZnO was hindered by the alloying. The alloyed coatings were covered by more compact layers of corrosion products with lower electric conductivity and better barrier properties.
Effects of copper on the microstructure and properties of Mg‐17Al‐3Zn alloys
Authors: Chen L. , Wu Z. , Xiao D.‐H. , Geng Z.‐W. , Zhou P.‐F.
Published: February 2015

In order to find good candidate materials for degradable fracturing ball applications, the microstructure, mechanical behavior and corrosion properties of as‐cast Mg‐17Al‐3Zn‐xCu alloys were investigated using optical microscope, scanning electronic microscope equipped with energy dispersive spectroscope, compression tests, electrochemical measurements, and immersion tests. The results show that Cu addition affects not only the amount but also the morphology and distribution of T‐phases. The distribution of Al also has a large dependence on Cu concentration. These modifications of the microstructures accordingly affect the mechanical and corrosion properties of the investigated alloys. Mg‐17Al‐3Zn‐5Cu alloy can be used as degradable fracturing ball.
Totally non‐immune sets
Authors: Tzouvaras Athanassios
Published: February 2015

Let be a countable first‐order language and be an ‐structure. “Definable set” means a subset of M which is ‐definable in with parameters. A set is said to be immune if it is infinite and does not contain any infinite definable subset. X is said to be partially immune if for some definable A, is immune. X is said to be totally non‐immune if for every definable A, and are not immune. Clearly every definable set is totally non‐immune. Here we ask whether the converse is true and prove that it is false for every countable structure whose class of definable sets satisfies a mild condition. We investigate further the possibility of an alternative construction of totally non‐immune non‐definable sets with the help of a subclass of immune sets, the class of cohesive sets, as well as with the help of a generalization of definable sets, the semi‐definable ones (the latter being naturally defined in models of arithmetic). Finally connections are found between totally non‐immune sets and generic classes in nonstandard models of arithmetic.
Synthesis of Bottlebrush Polystyrenes with Uniform, Alternating, and Gradient Distributions of Brushes Via Living Anionic Polymerization and Hydrosilylation
Authors: Ma Hongwei , Wang Qiuyun , Sang Wei , Han Li , Liu Pibo , Chen Jun , Li Yang , Wang Yurong
Published: February 2015

By combining living anionic polymerization and hydrosilylation, densely grafted bottlebrush polymers with controlled spacing of branch points are prepared. Dimethyl(4‐vinylphenyl)silane and dimethyl(4‐(1‐phenylvinyl)phenyl)silane are anionically (co)polymerized to synthesize uniform, alternating, and gradient in‐chain silyl–hydride (Si–H) functionalized backbones. The spacing of branch points is controlled effectively by regulating the distribution of Si–H groups along the backbones. Three backbones with a similar number of Si–H groups but variable distributions are used to synthesize corresponding bottlebrush polymers via hydrosilylation between the backbones and chain‐end vinyl functionalized polystyrene. The uniformly grafted bottlebrush exhibits the highest hydrodynamic radius (Rh) of 5.6 nm and the lowest Tg of 79 °C which may be attributed to its compact grafted structure. This methodology exhibits high efficiency and convenience for the construction of bottlebrushes with controlled distribution of brushes.

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Self‐Assembly of Amphiphilic Block Copolymer‐Tethered Nanoparticles: a New Approach to Nanoscale Design of Functional Materials
Authors: Liu Yi , Liu Yijing , Yin Jun‐Jie , Nie Zhihong
Published: February 2015

Colloidal molecules constructed from polymers and nanoparticles (NPs) have recently emerged as a novel class of building blocks for assembling functional hybrid materials. Particularly, self‐assembly of amphiphilic block copolymer (BCP)‐tethered NPs (BNPs) has shown great promise in the nanoscale design of functional hybrid materials. On the one hand, structurally the BNPs can be considered as molecular equivalents that are capable of self‐assembly at multiple hierarchical levels. On the other hand, the assembly of BNPs shows significant differences from molecular assembly due to their large dimension, complex geometry, and multi‐scale interactions involved in the assembly process. The manipulation of BCPs localized near the surface of the NPs offers an effective tool for engineering the interactions between NPs and hence the complexity of NP assembly. In this Feature Article, recent progresses on the self‐assembly of BNPs into functional materials are summarized. First, major strategies for assembling amphiphilic BNPs are highlighted. Secondly, the application of hybrid nanostructures (e.g., vesicles) assembled from BNPs in the field of biomedical imaging and delivery is discussed. Finally, current challenges and perspectives at this frontier are outlined.

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Fatigue improvement of welded steel joints by high frequency mechanical impact treatment
Authors: Marquis G. B. , Yıldırım H. C.
Published: February 2015

The International Institute of Welding (IIW) technical working units provide unique forums for knowledge exchange to experts and professionals from industry, research institutes and world‐leading universities. Developing science‐based and industrially‐relevant best practice guidelines is a key objective of these units.

In the past decade, high frequency mechanical impact (HFMI) has significantly developed as a reliable, effective and user‐friendly method for post‐weld fatigue strength improvement technique for welded steel structures. The development of a new guideline for the design of structures improved using high frequency mechanical impact is presented. The extra fatigue strength benefit for high frequency mechanical impact treated high strength steels is also presented. Important issues like high frequency mechanical impact equipment, proper treatment procedures, operator safety, training, quality control measures and documentation are briefly discussed. Aspects of this guideline and the unique international nature of the IIW which has made it possible are described.
Navier–Stokes equations with Navier boundary condition
Authors: Amrouche Chérif , Rejaiba Ahmed
Published: February 2015

In this paper, we study the Navier–Stokes equations with Navier boundary conditions in a bounded domain of
. We prove the existence of weak solution in W1,p(Ω) × Lp(Ω) for
by using fixed point theorem for the case
. Copyright © 2015 John Wiley & Sons, Ltd.
Exact controllability for Bresse system with variable coefficients
Authors: Soriano J. A. , Schulz R. A.
Published: February 2015

This paper is concerned with the internal exact controllability of a generalized Bresse system with variable coefficients, which the controls functions acts in an arbitrarily small subinterval (l1,l2) of (0,L). Our computation suggests a minimal time control and a region where the controls are more effective. The variable coefficients can be viewed as a generalization of Laplacian operator. The main result is obtained by applying Hilbert Uniqueness Method proposed by Lions, without using the Holmgren's uniqueness theorem or the hypothesis of equal‐speed waves of propagation. Copyright © 2015 John Wiley & Sons, Ltd.
Infinitely many homoclinic orbits for a class of second‐order damped differential equations
Authors: Zhang Chuanfang , Han Zhiqing
Published: February 2015

We investigate the existence and multiplicity of homoclinic orbits for the second‐order damped differential equations For Equation 1 where L(t) and W(t,u) are neither autonomous nor periodic in t. Under certain assumptions on g, L, and W, we get infinitely many homoclinic orbits for superquadratic, subquadratic and concave–convex nonlinearities cases by using fountain theorem and dual fountain theorem in critical point theory. These results generalize and improve some existing results in the literature. Copyright © 2015 JohnWiley & Sons, Ltd.
Arterial spin labeled carotid MR angiography: A phantom study examining the impact of technical and hemodynamic factors
Authors: Koktzoglou Ioannis , Giri Shivraman , Piccini Davide , Grodzki David M. , Flanagan Oisin , Murphy Ian G. , Gupta NavYash , Collins Jeremy D. , Edelman Robert R.
Published: February 2015

Purpose

To quantify the accuracy of three‐dimensional (3D) radial arterial spin labeled (ASL) magnetic resonance angiography (MRA) using vascular models of carotid stenosis.

Methods

Eight vascular models were imaged at 1.5 Tesla using pulsatile flow waveforms at rates found in the internal carotid arteries (100–400 mL/min). The impacts of the 3D ASL imaging readout (fast low angle shot (FLASH) versus balanced steady‐state free precession (bSSFP)), ultrashort echo time imaging using a pointwise encoding time reduction with radial acquisition (PETRA), and model stenosis severity on the accuracy of vascular model display at the location of stenosis were quantified. Accuracy was computed vis‐à‐vis a reference bSSFP volume acquired under no flow. Comparisons were made with standard‐of‐care contrast‐enhanced MRA (CEMRA) and Cartesian time‐of‐flight (TOF) MRA protocols.

Results

For 50% and 70% stenoses, CEMRA was most accurate (respective accuracies of 81.7% and 78.6%), followed by ASL FLASH (75.7% and 71.8%), ASL PETRA (69.6% and 70.6%), 3D TOF (66.6% and 57.1%), ASL bSSFP (68.7% and 51.2%), and 2D TOF (65.1% and 50.6%).

Conclusion

Flow phantom imaging studies show that ASL MRA can improve the display of hemodynamically significant carotid arterial stenosis compared with TOF MRA, with FLASH and ultrashort echo time readouts being most accurate. Magn Reson Med 75:295–301, 2016. © 2015 Wiley Periodicals, Inc.