bluuebunny/crossref_metadata_2025 huggingface dataset:
Engineering Biomaterials for Myocardial Regeneration and Repair
Authors: Ruvinov Emil , Cohen Smadar
Published: October 2013

Augmentation of myocardial tissue regeneration processes in injured hearts represents a major challenge in cardiology as current therapeutic approaches do not regenerate the myocardial tissue. Herein, we describe three emerging biomaterial‐based strategies to treat heart injuries, as stand‐alone therapies or in combination with regeneration‐inducing signals and/or cells. One strategy relies on the injection of acellular biomaterials, at an early stage after myocardial infarction (MI); these materials replace the damaged extracellular matrix, maintain left ventricular (LV) thickness, and prevent the negative LV remodeling and progression to heart failure. This strategy is currently being investigated in advanced clinical trials using a novel alginate‐based biomaterial. The second strategy employs engineered biomaterials, spatially presenting multiple regeneration‐inducing factors, to promote myocardial tissue regeneration in chronic infarcted hearts. The recent attempts to understand the “natural capacity” of the myocardium to heal and the factors involved in these processes are promising to advance this therapy. The third strategy applies biomaterials to promote cardiac tissue engineering and create a pre‐vascularized cardiac patch to replace damaged or missing myocardial tissue. Collectively, this review emphasizes the increasing importance of biomaterials in cardiology, describes the engineering schemes used in their fabrication, and their implementation in various therapeutic strategies aimed at cardiac tissue regeneration and repair. It mainly highlights the contribution of our group in developing these strategies.
Gold‐Catalyzed Cascade Reactions of Alkynes for Construction of Polycyclic Compounds
Authors: Ohno Hiroaki
Published: October 2013

The development of cascade reactions is an area of considerable interest in modern organic chemistry. Efficient cascade reactions realize the economical synthesis of complex target molecules through multiple bond formations in a single operation. Elementary reactions that form fewer waste products are desirable in terms of atom economy and in order to suppress side product formation in sequential processes. Recent advances in homogeneous gold catalysis have opened up further possibilities for cascade reactions. In this review, recent advances in gold‐catalyzed cascade cyclizations of alkynes are summarized. In particular, cascade reactions based on nucleophilic/electrophilic addition, carbene cyclopropanation/insertion, ring expansion, and cycloaddition are highlighted. Notably, many of the cascade reactions shown in this mini‐review feature no theoretical waste products.
Gene Delivery by Liposomes
Authors: Nordling‐David Mirjam M. , Golomb Gershon
Published: October 2013

In gene therapy, genetic materials, such as plasmid DNA, antisense oligonucleotides (asODNs), and small interfering RNA (siRNA), can be used to treat or prevent disease. This includes replacing a mutated gene, inactivating a mutated gene, or introducing a new gene. Although gene therapy is a promising treatment option for a number of diseases (including inherited disorders, some types of cancer, and certain viral infections), successful gene therapy is hampered by the lack of effective delivery systems (viral and nonviral). There are several nonviral gene carriers, such as lipids, polymers, and peptides, that can be used for this purpose. Liposomal delivery of nucleic acids, such as plasmid DNA, asODNs, and siRNAs, represents a very promising nanocarrier system that is relatively safe and effective in delivering genes to targeted locations in the body. Lipoid‐based delivery systems have also been shown to be stable in serum and plasma, have improved biodistribution, prolonged circulation half‐life, and enhanced target tissue selectivity. The most common lipids used in liposomes are cationic lipids, which facilitate binding between their positively charged head group(s) to negatively charged nucleic acids. This review is focused on the most common methods of lipoid‐based nanocarriers of nucleic acids for gene therapy in vivo.
When NHC Ligands Make a Difference in Gold Catalysis
Authors: Gatineau David , Goddard Jean‐Philippe , Mouriès‐Mansuy Virginie , Fensterbank Louis
Published: October 2013

Thanks to their unique electronic and steric properties, carbene ligands offer highly valuable features for catalysis, including homogenous gold catalysis. The use of carbene‐gold complexes has improved existing reactions, either by modifying reactivity modes or by leading to highly asymmetric processes. These topics will be discussed on the basis of selected examples.
Engineering Cardiac Tissues from Pluripotent Stem Cells for Drug Screening and Studies of Cell Maturation
Authors: Miklas Jason W. , Nunes Sara S. , Radisic Milica
Published: October 2013

Using cardiomyocytes derived from human pluripotent stem cells (hPSC‐CMs), it is now possible to develop models of human cardiac diseases and to screen novel pharmaceutical agents on human cardiac cells and tissues. However, since hPSC‐CMs display an immature phenotype, significant focus has turned to cardiac tissue engineering to deliver a means to mature these cells. In this review we discuss the maturation state of currently available hPSC‐CMs and provide an overview of the processes involved in cardiomyocyte maturation. We then explore the differences between pathological and physiological hypertrophy and discuss how tissue engineering techniques that rely on the combined use of biomaterials and bioreactors can be utilized to enhance and study the hypertrophic response.
Induction of Angiogenesis and Vasculogenesis in Cell‐Embedded Biomaterials
Authors: Dado‐Rosenfeld Dekel , Levenberg Shulamit
Published: October 2013

The central role of prevascularization of engineered tissue grafts in postimplantational survival and integration is becoming increasingly appreciated. An in‐depth understanding of the regulating factors and intricacies of generation of three‐dimensional vascular networks in vitro will facilitate effective fabrication of clinically relevant vascularized tissues. In this review we aim to examine the influence of different biomaterials on vasculogenesis and angiogenesis, with particular focus on the impact of various matrix properties, such as composition, stiffness and geometry, on the resulting vasculature. Additionally, the contribution of externally applied mechanical forces, mimicking blood flow patterns, to tissue vascularization efforts is reviewed. We present here pivotal studies focusing on the influence of mechanical forces, such as shear stress and stretching tension, on vascular network formation in biomaterial‐based scaffolds. Comprehensive understanding of the key factors dictating the patterns and functionality of engineered vasculature will facilitate more efficient fabrication of viable tissue grafts, with a broad range of medical applications.
Multifunctional SilkTropoelastin Biomaterial Systems
Authors: Ghezzi Chiara E. , Rnjak‐Kovacina Jelena , Weiss Anthony S. , Kaplan David L.
Published: October 2013

New multifunctional, degradable, polymeric biomaterial systems would provide versatile platforms to address cell and tissue needs in both in vitro and in vivo environments. While protein‐based composites or alloys are the building blocks of biological organisms, similar systems have not been largely exploited, to date, to generate ad hoc biomaterials able to control and direct biological functions by recapitulating their inherent structural and mechanical complexities. Therefore, we have recently proposed silktropoelastin material platforms that are able to conjugate a mechanically robust and durable protein, silk, to a highly flexible and biologically active protein, tropoelastin. This review focuses on the elucidation of the interactions between silk and tropoelastin to control the structure of the material its properties, and ultimately functions. In addition, an approach is provided for novel material designs to provide tools to control biological outcomes through surface roughness, elasticity, and net charge for neuronal and mesenchymal stem‐cell‐based tissue engineering.
Core and Corona Modifications for the Design of Polymeric Micelle Drug‐Delivery Systems
Authors: McLaughlin Christopher K. , Logie Jennifer , Shoichet Molly S.
Published: October 2013

Polymeric nanoparticle micelles are formed from amphiphilic polymers with a hydrophobic core and a hydrophilic corona. Often comprised of a biodegradable, biocompatible polymer core and a poly(ethylene glycol) corona, these nanoparticle micelles encapsulate a hydrophobic drug and enable surface modification with targeting ligands. Strategies to enhance hydrophobic drug encapsulation are described as chemistries that facilitate covalent modification with antibodies using water‐based click chemistry.
The anomalous ionosphere between solar cycles 23 and 24
Authors: Solomon Stanley C. , Qian Liying , Burns Alan G.
Published: October 2013

The solar minimum period during 2008–2009 was characterized by lower thermospheric density than the previous solar minimum and lower than any previously measured. Recent work used the NCAR Thermosphere‐Ionosphere‐Electrodynamics General Circulation Model to show that the primary cause of density changes from 1996 to 2008 was a small reduction in solar extreme ultraviolet (EUV) irradiance, causing a decrease in thermospheric temperature and hence a contracted thermosphere. There are similar effects in the ionosphere, with most measurements showing an F region ionosphere that is unusually low in density, and in peak altitude. This paper addresses the question of whether model simulations previously conducted, and their solar, geomagnetic, and anthropogenic inputs, produce ionospheric changes commensurate with observations. We conducted a 15 year model run and obtained good agreement with observations of the global mean thermospheric density at 400 km throughout the solar cycle, with a reduction of ~30% from the 1996 solar minimum to 2008–2009. We then compared ionosonde measurements of the midday peak density of the ionospheric F region (NmF2) to the model simulations at various locations. Reasonable agreement was obtained between measurements and the model, supporting the validity of the neutral density comparisons. The global average NmF2 was estimated to have declined between the two solar minima by ~15%. In these simulations, a 10% reduction of solar EUV plays the largest role in causing the ionospheric change, with a minor contribution from lower geomagnetic activity and a very small additional effect from anthropogenic increase in CO2.
Interannual fluctuations in the seasonal cycle of nitrous oxide and chlorofluorocarbons due to the Brewer‐Dobson circulation
Authors: Simmonds P. G. , Manning A. J. , Athanassiadou M. , Scaife A. A. , Derwent R. G. , O'Doherty S. , Harth C. M. , Weiss R. F. , Dutton G. S. , Hall B. D. , Sweeney C. , Elkins J. W.
Published: October 2013

The tropospheric seasonal cycles of N2O, CFC‐11 (CCl3F), and CFC‐12 (CCl2F2) are influenced by atmospheric dynamics. The interannually varying summertime minima in mole fractions of these trace gases have been attributed to interannual variations in mixing of stratospheric air (depleted in CFCs and N2O) with tropospheric air with a few months lag. The amount of wave activity that drives the stratospheric circulation and influences the winter stratospheric jet and subsequent mass transport across the tropopause appears to be the primary cause of this interannual variability. We relate the observed seasonal minima of species at three Northern Hemisphere sites (Mace Head, Ireland; Trinidad Head, U.S.; and Barrow, Alaska) with the behavior of the winter stratospheric jet. As a result, a good correlation is obtained between zonal winds in winter at 10 hPa, 58°N–68°N, and the detrended seasonal minima in the stratosphere‐influenced tracers. For these three tracers, individual Pearson correlation coefficients (r) between 0.51 and 0.71 were found, with overall correlations of between 0.67 and 0.77 when “composite species” were considered. Finally, we note that the long‐term observations of CFCs and N2O in the troposphere provide an independent monitoring method complementary to satellite data. Furthermore, they could provide a useful observational measure of the strength of stratosphere‐troposphere exchange and, thus, could be used to monitor any long‐term trend in the Brewer‐Dobson circulation which is predicted by climate models to increase over the coming decades.
Variations in middle atmospheric water vapor from 2004 to 2013
Authors: Nedoluha Gerald E. , Michael Gomez R. , Allen Doug R. , Lambert Alyn , Boone Chris , Stiller Gabriele
Published: October 2013

We show measurements of middle atmospheric water vapor as measured by two ground‐based Water Vapor Millimeter‐wave Spectrometer instruments and three satellite‐based instruments: the Aura Microwave Limb Sounder, the Atmospheric Chemistry Experiment (ACE), and the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). We also show CH4 measurements from the MIPAS and ACE instruments and use these to help interpret the H2O variations. We find that interannual changes in stratospheric H2O of ~0.5 ppmv, observed from Table Mountain, California, at 26 km and 40 km from 2010 to 2012, are caused primarily by dynamically driven changes in CH4 during this period. The interannual variations in H2O observed over Mauna Loa, Hawaii, are shown to be quite similar to the average variations observed over 50°S–50°N in the lower mesosphere; thus, we conclude that a single ground‐based microwave instrument can provide a useful estimate of interannual globally averaged lower mesospheric H2O variations, even when such changes are as small as ~0.2–0.3 ppmv. We find that the increase of ~0.2–0.3 ppmv in H2O in the lower mesosphere since 2006 is qualitatively consistent with an increase in tropical tropopause temperature since around 2001.
A rapid and highly specific method to evaluate the presence of pyrrolizidine alkaloids in Borago officinalis seed oil
Authors: Vacillotto Giulio , Favretto Donata , Seraglia Roberta , Pagiotti Rita , Traldi Pietro , Mattoli Luisa
Published: October 2013

Pyrrolizidine alkaloids (PAs) are complex molecules, present in plants as free bases and N‐oxides. They are known for their hepatotoxicity, and consequently there is a health risk associated with the use of medicinal herbs that contain PAs. Unfortunately, there is no international regulation of PAs in foods, unlike those for herbs and medicines: in particular, for herbal preparation or herbal extracts, the total PA content must not exceed 1 µg/kg or 1 µg/l, respectively. Borago officinalis seed oil is a source of γ‐linolenic acid, and its use is increased in both pharmaceutical and health food industries. Even if studies based on gas chromatography and TLC methods showed that PAs are not co‐extracted with oil, the development of a rapid and sensitive method able to evaluate the presence of PAs in commercially available products is surely of interest. The presence of PAs in a commercially available Borago officinalis seed oil was tested either in the oil sample diluted with tetrahydrofuran/methanol (MeOH)/H2O (85/10/5 v:v:v) or after extraction with MeOH/H2O (50/50 v:v) solution The samples were analysed by electrospray ionization in positive ion mode and in high mass resolution (60 000) conditions. In both cases to evaluate the effectiveness of the method, spiking experiments were performed adding known amount of two PA standards to the borage seed oil. A limit of detection in the order of 200 ppt was determined for these two compounds, strongly analogous to Borago officinalis seed oil PAs. Consequently, if present, PAs level in Borago officinalis seed oil must lower than 200 ppt. Copyright © 2013 John Wiley & Sons, Ltd.
Mapping the glycation sites in the neoglycoconjugate from hexasaccharide antigen of Vibrio cholerae, serotype Ogawa and the recombinant tetanus toxin C‐fragment carrier
Authors: Jahouh Farid , Xu Peng , Vann Willie F. , Kováč Pavol , Banoub Joseph H.
Published: October 2013

We report herein the glycation sites in a vaccine candidate for cholera formed by conjugation of the synthetic hexasaccharide fragment of the O‐specific polysaccharide of Vibrio cholerae, serotype Ogawa, to the recombinant tetanus toxin C‐fragment (rTT–Hc) carrier. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry analysis of the vaccine revealed that it is composed of a mixture of neoglycoconjugates with carbohydrate : protein ratios of 1.9 : 1, 3.0 : 1, 4.0 : 1, 4.9 : 1, 5.9 : 1, 6.9 : 1, 7.9 : 1 and 9.1 : 1. Liquid chromatography tandem mass spectrometry (LC‐MS/MS) analysis of the tryptic and GluC V8 digests allowed identification of 12 glycation sites in the carbohydrate–protein neoglycoconjugate vaccine. The glycation sites are located exclusively on lysine (Lys) residues and are listed as follows: Lys 22, Lys 61, Lys 145, Lys 239, Lys 278, Lys 318, Lys 331, Lys 353, Lys 378, Lys 389, Lys 396 and Lys 437. Based on the 3‐D representation of the rTT–Hc protein, all the glycation sites correspond to lysines located at the outer surface of the protein. Copyright © 2013 John Wiley & Sons, Ltd.
Shotgun‐proteomics‐based clinical testing for diagnosis and classification of amyloidosis
Authors: Theis Jason D. , Dasari Surendra , Vrana Julie A. , Kurtin Paul J. , Dogan Ahmet
Published: October 2013

Shotgun proteomics technology has matured in the research laboratories and is poised to enter clinical laboratories. However, the road to this transition is sprinkled with major technical unknowns such as long‐term stability of the platform, reproducibility of the technology and clinical utility over traditional antibody‐based platforms. Further, regulatory bodies that oversee the clinical laboratory operations are unfamiliar with this new technology. As a result, diagnostic laboratories have avoided using shotgun proteomics for routine diagnostics. In this perspectives article, we describe the clinical implementation of a shotgun proteomics assay for amyloid subtyping, with a special emphasis on standardizing the platform for better quality control and earning clinical acceptance. This assay is the first shotgun proteomics assay to receive regulatory approval for patient diagnosis. The blueprint of this assay can be utilized to develop novel proteomics assays for detecting numerous other disease pathologies. Copyright © 2013 John Wiley & Sons, Ltd.
N‐alkylpyridinium quaternization for assisting electrospray ionization of sterols in oil by quadrupole‐time of flight mass spectrometry
Authors: Wang Hang , Wang Haoyang , Zhang Li , Zhang Jing , Leng Jiapeng , Cai Tingting , Guo Yinlong
Published: October 2013

Rationale: The illegal cooking oil has become a serious social problem and raised widespread alarm recently. However, an efficient and sensitive technique for identifying the potential illegal cooking oil is still unavailable, especially when mixed with the ordinary ones; there is an urgent need to develop an efficient method for identifying the illegal cooking oil. Sterols in the cooking oil could be used as an indicator to identify the source and quality of oil by detecting the kinds of phytosterols and zoosterols. However, those sterols are difficult to be ionized by electrospray ionization, which resulted in the low sensitivity in electrospray ionization (ESI)‐mass spectrometric (MS) analysis.

Methods: N‐alkylpyridinium isotope quaternization was extended to charge label sterols in different cooking oil and attached N‐cationic pyridinium tag onto the sterols in the presence of trifluoromethanesulfonic anhydride (Tf2O); the kinds of sterols were identified and quantified by comparing d0/d5 pairs and product scan from ESI‐quadrupole‐time of flight (Q‐TOF) MS analysis.

Results: The derivatized sterols were attached with permanent charge, resulting in the significant enhancement of ionization in ESI‐Q‐TOF MS analysis. The detection limits of analytes were improved to 0.02–0.05 ng/mL; different kinds of phytosterol, zoosterol and oxides were identified and quantified by comparing d0/d5 pairs from full scan and product scan. The method was applied in the detection of zoosterol for identifying the potential recycled cooking oil, even when the illegal oil has been blended into the ordinary one. More zoosterol was detected in the recycled oil compared with other cooking oil.

Conclusions: The use of N‐alkylpyridinium isotope quaternization method provided an alternative method for identifying the potential illegal cooking oil. Copyright © 2013 John Wiley & Sons, Ltd.
Universal Approach for Structural Interpretation of QSAR/QSPR Models
Authors: Polishchuk Pavel G. , Kuz'min Victor E. , Artemenko Anatoly G. , Muratov Eugene N.
Published: October 2013

In this paper we offer a novel approach for the structural interpretation of QSAR models. The major advantage of our developed methodology is its universality, i.e., it can be applied to any QSAR/QSPR model irrespective of chemical descriptors and machine learning methods applied. This universality was achieved by using only the information obtained from substructures of the compounds of interest to interpret model outcomes. Reliability of the offered approach was confirmed by the results of three case studies, including end‐points of different types (continuous and binary classification) and nature (solubility, mutagenicity, and inhibition of Transglutaminase 2), various fragment and whole‐molecule descriptors (Simplex and Dragon), and multiple modeling techniques (partial least squares, random forest, and support vector machines). We compared the global contributions of molecular fragments obtained using our methodology with known SAR rules derived experimentally. In all cases high concordance between our interpretation and results published by others was observed. Although the proposed interpretation approach could be easily extended to any type of descriptors, we would recommend using Simplex descriptors to achieve a larger variety of investigated molecular fragments. The developed approach is a good tool for interpretation of such “black box” models like random forest, neural networks, etc. Analysis of fragment global contributions and their deviation across a dataset could be useful for the identification of key fragments and structural alerts. This information could be helpful to maximize the positive influence of structural surroundings on the given fragment and to decrease the negative effects.
AdS black holes with arbitrary scalar coupling
Authors: Caldarelli Marco M. , Charmousis Christos , Hassaïne Mokhtar
Published: October 2013

Abstract

A general class of axionic and electrically charged black holes for a self-interacting scalar field nonminimally coupled to Einstein gravity with a negative cosmological constant is presented. These solutions are the first examples of black holes with an arbitrary nonminimal coupling ξ in four dimensions. Moreover, due to the presence of two three-forms fields, the topology of the horizon of these black holes is planar. We discuss some properties of these solutions electing particular values of the nonminimal coupling parameter. A special case arises when ξ = 1/4, for which the gravitational field is confined in a region close to the event horizon. We also show that these black holes emerge from stealth AdS configurations as the axionic fields are switched on, and that they can be generated through a Kerr-Schild transformation. Finally, in the appendix, we extend these results to arbitrary dimension.
The MSSM Higgs sector at a high MSUSY: reopening the low tan β regime and heavy Higgs searches
Authors: Djouadi Abdelhak , Quevillon Jérémie
Published: October 2013

Abstract

One of the main implications of the LHC discovery of a Higgs boson with a massMh ≈ 126 GeV is that the scale of supersymmetry-breaking in the Minimal Supersymmetric Standard Model (MSSM) might be rather high,MS ≫ MZ. In this paper, we consider the highMSregime and study the spectrum of the extended Higgs sector of the MSSM, including the LHC constraints on the mass and the rates of the observed lighthstate. In particular, we show that in a simplified model that approximates the important radiative corrections, the unknown scaleMS(and some other leading SUSY parameters) can be traded against the measured value ofMh. One would be then essentially left with only two free parameters to describe the Higgs sector, tanβand the pseudoscalar Higgs massMA, even at higher orders. The main phenomenological consequence of these highMSvalues is to reopen the low tanβregion, tanβ ≲ 3–5, which was for a long time buried under the LEP constraint on the lightesthmass when a low SUSY scale was assumed. We show that, in this case, the heavier MSSM neutralH/Aand chargedH±states can be searched for in a variety of interesting final states such as decays into gauge and lighter Higgs bosons (in pairs on in mixed states) and decays into heavy top quarks. Examples of sensitivity on the [tanβ, MA] parameter space at the LHC in these channels are given.
Lysophosphatidic acid stimulates hyaluronan production by mouse cumulus–oocyte complexes
Authors: Kuwahara Emi , Yamamoto Junpei , Yano Yuya , Omura Midori , Kuwahara Akira , Irahara Minoru , Tokumura Akira
Published: October 2013

Purpose

In mammals, cumulus expansion due to increased synthesis of hyaluronan was suggested to correlate with modification of the gap junction between cumulus cells and the oocyte, leading to cumulus expansion. We examined whether lysophosphatidic acid, a lipid mediator detected in mammalian body fluids, stimulates significant production of hyaluronan and thus affects mouse cumulus expansion in vitro.

Methods

Cumulus–oocyte complexes isolated from the gonadotropin‐treated ovaries of B6C3F1 mice were exposed to lysophosphatidic acid in the presence and absence of 0.3 % fetal bovine serum for measurement of cumulus expansion and released hyaluronan, respectively.

Results

Exogenously added lysophosphatidic acid concentration‐dependently stimulated production of hyaluronan in the cumulus cell–oocyte complex, and the stimulatory effect of lysophosphatidic acid on hyaluronan production was mediated through the signal pathways, including LPA receptor‐Gi coupling, EGF receptor transactivation, and activations of phosphatidylinositol‐specific phospholipase C, protein kinase C and mitogen‐activated protein kinases. LPA increased mRNA expression of tumor necrosis α‐induced protein 6, a hyaluronan‐binding protein, and expansion of cumulus cell–oocyte complex.

Conclusions

Lysophosphatidic acid in follicular fluids may participate in physiological cumulus expansion before ovulation by stimulating production of hyaluronan and proteins that enable the association of hyaluronan with cumulus cells and oocytes.
McDonald's Apology over a Pig Toy: A Cultural Territorial Clash
Authors: Quek Guan Cheng , Ling Peter
Published: October 2013

McDonald's introduced a modified Chinese zodiac promotion to celebrate Chinese New Year in Singapore in 2010. Instead of the traditional 12 zodiac animals – rat, ox, tiger, rabbit, dragon, snake, horse, sheep, monkey, rooster, dog, and pig – McDonald's replaced the pig symbol with a Cupid toy because Valentine's Day fell on the same day as Chinese New Year in 2010 and because the restaurant's Muslim customers do not consume pork. This paper aimed to find out how and why customers of McDonald's rejected the zodiac promotion in Singapore through heated discussions in the media. Following a review of literature on multiculturalism, cultural sensitivity and hybrid cultural theories, a Foucault-based framework of discipline-ethics-performativity guided this qualitative text analysis of 97 documents from forum pages of the Straits Times newspaper and online postings on Asia One and Channel News Asia. Mass media asserted that it was a racial issue related to extreme political correctness that fuelled the controversy but the emerging theory was that there was a cultural territorial clash of discipline structures, ethical moderation, and identity performance. This paper contributes to literature on business in Asia, as there seems to be little research on pig symbolism in Marketing or on the failure of culturally oriented marketing activities. The implication for practice is that the marketing team needs to consider more carefully the fundamental cultural disciplinary structure, ethics responsibility, and identity performativity in a multi-ethnic country. While McDonald's zodiac promotion appeared not to have upset the Muslims in multi-racial Singapore, it would be interesting to research whether there was any online backlash in Malaysia and Indonesia, which have a higher Muslim population.
The X‐ray crystal structure of APR‐B, an atypical adenosine 5′‐phosphosulfate reductase from Physcomitrella patens
Authors: Stevenson Clare E.M. , Hughes Richard K. , McManus Michael T. , Lawson David M. , Kopriva Stanislav
Published: October 2013

Sulfonucleotide reductases catalyse the first reductive step of sulfate assimilation. Their substrate specificities generally correlate with the requirement for a [Fe4S4] cluster, where adenosine 5′‐phosphosulfate (APS) reductases possess a cluster and 3′‐phosphoadenosine 5′‐phosphosulfate reductases do not. The exception is the APR‐B isoform of APS reductase from the moss Physcomitrella patens, which lacks a cluster. The crystal structure of APR‐B, the first for a plant sulfonucleotide reductase, is consistent with a preference for APS. Structural conservation with bacterial APS reductase rules out a structural role for the cluster, but supports the contention that it enhances the activity of conventional APS reductases.
Functional and structural characterisation of a viral cytochrome b5
Authors: Reid Emma L. , Weynberg Karen D. , Love John , Isupov Michail N. , Littlechild Jennifer A. , Wilson William H. , Kelly Steven L. , Lamb David C. , Allen Michael J.
Published: October 2013

Cytochrome b5 is a ubiquitous electron transport protein. The sequenced viral OtV‐2 genome, which infects Ostreococcus tauri, was predicted to encode a putative cytochrome b5 enzyme. Using purified OtV‐2 cytochrome b5 we confirm this protein has identical spectral properties to purified human cytochrome b5 and additionally that the viral enzyme can substitute for yeast cytochrome b5 in yeast cytochrome P450 51 mediated sterol 14α‐demethylation. The crystal structure of the OtV‐2 cytochrome b5 enzyme reveals a single domain, comprising four β sheets, four α helices and a haem moiety, which is similar to that found in larger eukaryotic cytochrome proteins. As a product of a horizontal gene transfer event involving a subdomain of the host fumarate reductase‐like protein, OtV‐2 cytochrome b5 appears to have diverged in function and is likely to have evolved an entirely new role for the virus during infection. Indeed, lacking a hydrophobic C‐terminal anchor, OtV‐2 encodes the first cytosolic cytochrome b5 characterised. The lack of requirement for membrane attachment (in contrast to all other microsomal cytochrome b5s) may be a reflection of the small size of the host cell, further emphasizes the unique nature of this virus gene product and draws attention to the potential importance of cytochrome b5 metabolic activity at the extremes of cellular scale.
Induced Pluripotent Stem Cells Are Sensitive to DNA Damage
Authors: Zhang Minjie , Yang Caiyun , Liu Huixian , Sun Yingli
Published: October 2013

Induced pluripotent stem cells (iPSCs) resemble embryonic stem cells (ESCs) in morphology, gene expression and in vitro differentiation, raising new hope for personalized clinical therapy. While many efforts have been made to improve reprogramming efficiency, significant problems such as genomic instability of iPSCs need to be addressed before clinical therapy. In this study, we try to figure out the real genomic state of iPSCs and their DNA damage response to ionizing radiation (IR). We found that iPSC line 3FB4-1 had lower DNA damage repair ability than mouse embryonic fibroblast (MEF) cells, from which 3FB4-1line was derived. After the introduction of DNA damage by IR, the number of γ-H2AX foci in 3FB4-1 increased modestly compared to a large increase seen in MEF, albeit both significantly (P  < 0.01). In addition, whole-genome sequencing analysis showed that after IR, 3FB4-1 possessed more point mutations than MEF and the point mutations spread all over chromosomes. These observations provide evidence that iPSCs are more sensitive to ionizing radiation and their relatively low DNA damage repair capacity may account for their high radiosensitivity. The compromised DNA damage repair capacity of iPSCs should be considered when used in clinical therapy.
Landscape evolution of the Ulan Buh Desert in northern China during the late Quaternary
Authors: Chen Fahu , Li Guoqiang , Zhao Hui , Jin Ming , Chen Xuemei , Fan Yuxin , Liu Xiaokang , Wu Duo , Madsen David
Published: October 2013

The evolution of arid environments in northern China was a major environmental change during the Quaternary. Here we present the dating and environmental proxy results from a 35 m long core (A-WL10ZK-1) collected from the Ulan Buh Desert (UBD), along with supplemental data from four other cores. The UBD is one of the main desert dune fields in China and our results indicate the UBD has undergone complex evolution during the late Quaternary. Most of the present UBD was covered by a Jilantai-Hetao Mega-paleolake lasting until ~ 90 ka ago. A sandy desert environment prevailed throughout the UBD during the last glacial period and early Holocene. A wetland environment characterized by the formation of numerous interdunal ponds in the northern UBD occurred at ~ 8–7 ka, although a dune field persisted in the southern UBD. The modern UBD landscape formed after these wetlands dried up. During the last 2000 years, eolian sand from the Badain Jaran Desert has invaded the northern UBD, while farming and overgrazing resulted in the formation of the eastern UBD. We suggest that the formation of UBD landforms is related to the disintegration of the megalake Jilantai-Hetao and to summer monsoon changes during the last glaciation and Holocene.
Hepatologische Scores
Authors: Tonko Sebastian , Dufour Jean-François
Published: October 2013

Die folgenden hepatologischen Scores sind hilfreich dabei den Schweregrad für Lebererkrankungen einschätzen zu können, manche helfen bei der Diagnosestellung, andere können sogar dazu verwendet werden um eine Prognose für die weitere Entwicklung zu zeigen. Wir entschieden uns für 5 Scores welche im klinischen Alltag sehr nützlich sind: Child-Pugh-Turcotte-Score(CTP); MELD-Score, Score zur Diagnose einer Autoimmunhepatitis, den Mayo-Score für primär biliäre Zirrhose und den Lille-Score für alkoholische Hepatitis. In allen Scores werden klinische Merkmale und laborchemische Parameter verwendet um diese Aussagen treffen zu können.
Wichtige Stadieneinteilungen und Scores in der Kardiologie
Authors: Bonetti Piero O.
Published: October 2013

In der Kardiologie werden diverse Einteilungen zur Quantifizierung von Symptomen und zur Gradierung von Krankheitsstadien eingesetzt. Ebenso spielen spezielle Scores bei der Risikoabschätzung verschiedenster kardiologischer Krankheitsbilder eine große Rolle und stellen in vielen Fällen einen entscheidenden Faktor bei der therapeutischen Entscheidungsfindung dar. Im Folgenden soll auf einige der im klinischen Alltag am häufigsten verwendeten, kardiologischen Stadieneinteilungen und Scores näher eingegangen werden. Die NYHA-Klassifikation zur Gradierung des Schweregrades der Symptomatik von Patienten mit Herzerkrankungen ist wohl eine der bekanntesten medizinischen Stadieneinteilungen überhaupt. Ebenfalls häufig angewendet wird die CCS-Klassifikation, die der Einteilung des Schweregrades pektanginöser Beschwerden bei Patienten mit stabiler koronarer Herzkrankheit dient. Etwas in Vergessenheit geraten ist die Killip-Klassifikation, welche ein einfaches, klinisches Instrument zur Abschätzung des Mortalitätsrisikos von Patienten mit akutem Koronarsyndrom darstellt. Während bei Patienten mit akutem ST-Hebungsinfarkt (STEMI) das therapeutische Vorgehen – d. h. die notfallmäßige Koronarreperfusion mittels Thrombolyse oder besser mittels primärer perkutaner Koronarintervention – in der Regel unbestritten ist, richtet sich das diagnostische und therapeutische Vorgehen bei Patienten mit akutem Koronarsyndrom ohne ST-Hebung (NSTE-ACS) nach deren individuellem Risiko. Um das Risiko von Patienten mit NSTE-ACS möglichst frühzeitig abschätzen zu können, stehen diverse Scores zur Verfügung, wobei der TIMI risk score und der GRACE score die derzeit am gebräuchlichsten sind. Bei Patienten mit Vorhofflimmern – der häufigsten klinisch relevanten Rhythmusstörung – kommt der Prävention thromboembolischer Ereignisse besondere Bedeutung zu. Auch hier helfen Scores wie der CHA2DS2-VASc-Score und der HAS-BLED-Score bei der Beurteilung des Thromboembolierisikos resp. bei der Abschätzung des unter einer Antikoagulation zu erwartenden Blutungsrisikos, was eine optimale Indikationsstellung zur Einleitung einer Antikoagulation erlaubt und so zur Verbesserung der Prognose betroffener Patienten beiträgt.
Scores und Stadien in der Neurologie
Authors: Beer Serafin
Published: October 2013

Neurologische Scores und Stadieneinteilungen erlauben uns, Funktionsdefizite standardisiert zu quantifizieren und Krankheitsverläufe zu beschreiben. Diese Assessment-Instrumente können als Entscheidungsgrundlage dienen für rationale diagnostische oder therapeutische Entscheidungen sowie zur Evaluation alter oder neuer Therapieverfahren. Leider entsprechen auch in der Neurologie die am häufigsten eingesetzten Scores oft nicht den geforderten Gütekriterien bezüglich Reliabilität, Validität sowie Sensitivität/Spezifität. Andererseits sind weiterentwickelte, validere Messinstrumente aufgrund ihrer Komplexität und des hohen Zeitaufwandes kaum praxistauglich. Auch können in der Regel durch komplexe Scores und Stadienbeschreibungen nur einige Aspekte eines Störungsbildes wiedergegeben werden. Die präzise Beschreibung klinischer Phänomene und Krankheitsbilder bleibt somit auch in der Neurologie ein zentraler Aspekt zur umfassenden Erfassung und Darstellung neurologischer Störungen.
Solving the Schroedinger equation using Smolyak interpolants
Authors: Avila Gustavo , Carrington Tucker
Published: October 2013

In this paper, we present a new collocation method for solving the Schroedinger equation. Collocation has the advantage that it obviates integrals. All previous collocation methods have, however, the crucial disadvantage that they require solving a generalized eigenvalue problem. By combining Lagrange-like functions with a Smolyak interpolant, we device a collocation method that does not require solving a generalized eigenvalue problem. We exploit the structure of the grid to develop an efficient algorithm for evaluating the matrix-vector products required to compute energy levels and wavefunctions. Energies systematically converge as the number of points and basis functions are increased.
Bias free magnetomechanical coupling on magnetic microwires for sensing applications
Authors: Herrero-Gómez C. , Marín P. , Hernando A.
Published: October 2013

In the present paper, we report a systematic study of the magnetoelastic resonance of amorphous magnetic microwires of composition Fe73Si11B13Nb3. The study was performed for samples annealed at different temperatures. It was observed that such microwires present the key feature of performing magnetoelastic resonance in the absence of applied field. This fact, in addition to their small size, gives the microwires unique advantages over the widespreaded ribbons, currently in use as magnetoelastic sensors. Beyond the study of the resonance, magnetic properties of the samples were studied by means of Vibrating Sample Magnetometer (VSM) measurement in order to find an explanation to their bias-free resonance property. Finally, we show two possible applications of microwire based magnetoelastic sensors, a fluid density sensor and a mass-loading sensor.
Secondary relaxations in a series of organic phosphate glasses revealed by dielectric spectroscopy
Authors: Kahlau R. , Dörfler T. , Rössler E. A.
Published: October 2013

Dielectric susceptibility spectra of six chemically similar organic phosphate glass formers are analyzed in order to elucidate the spectral evolution of a multitude of secondary (β) relaxation processes dominating the dielectric loss below the glass transition temperature Tg. By doing the spectral analysis we forgo any data fitting procedure and apply a model independent scaling approach instead. This approach assumes a constant distribution of activation energies g(E) underlying a plurality of thermally activated processes, which determine the β-relaxation. The scaling reveals temperature independent, asymmetric distributions g(E) for temperatures well below Tg. Simultaneously, the temperature dependence of the relaxation strength of the β-processes Δɛβ(T) is yielded, being nearly constant well in the glassy state. Already somewhat below Tg the spectral scaling fails and reveals an apparent increase of the mean activation energy, leading to a weaker temperature dependence of the mean relaxation times τβ(T). In the same temperature regime Δɛβ(T) starts to increase drastically, i.e., the softening of the glass near Tg is reflected directly in the loss of temperature independence of g(E) and Δɛβ(T). Comparing the different glasses made from phosphate molecules with increasing number of internal degrees of freedom we do not see systematic changes in the spectral evolution. In some cases even identical distributions g(E) are found.
Alternative separation of exchange and correlation energies in multi-configuration range-separated density-functional theory
Authors: Stoyanova Alexandrina , Teale Andrew M. , Toulouse Julien , Helgaker Trygve , Fromager Emmanuel
Published: October 2013

The alternative separation of exchange and correlation energies proposed by Toulouse et al. [Theor. Chem. Acc. 114, 305 (2005)] is explored in the context of multi-configuration range-separated density-functional theory. The new decomposition of the short-range exchange–correlation energy relies on the auxiliary long-range interacting wavefunction rather than the Kohn–Sham (KS) determinant. The advantage, relative to the traditional KS decomposition, is that the wavefunction part of the energy is now computed with the regular (fully interacting) Hamiltonian. One potential drawback is that, because of double counting, the wavefunction used to compute the energy cannot be obtained by minimizing the energy expression with respect to the wavefunction parameters. The problem is overcome by using short-range optimized effective potentials (OEPs). The resulting combination of OEP techniques with wavefunction theory has been investigated in this work, at the Hartree-Fock (HF) and multi-configuration self-consistent-field (MCSCF) levels. In the HF case, an analytical expression for the energy gradient has been derived and implemented. Calculations have been performed within the short-range local density approximation on H2, N2, Li2, and H2O. Significant improvements in binding energies are obtained with the new decomposition of the short-range energy. The importance of optimizing the short-range OEP at the MCSCF level when static correlation becomes significant has also been demonstrated for H2, using a finite-difference gradient. The implementation of the analytical gradient for MCSCF wavefunctions is currently in progress.
Current-voltage characteristics of coupled photodiode-electrocatalyst devices
Authors: Shaner Matthew R. , Fountaine Katherine T. , Lewerenz Hans-Joachim
Published: October 2013

Analytical expressions for the illuminated current-voltage characteristics of coupled photodiode-electrocatalyst fuel forming devices are derived. The approach is based on combining solid-state diode behavior with metal electrochemistry via the diode equation and the Butler-Volmer equation (charge transfer coefficients: αA = αC = α) or the Tafel equation (|η|≥118mVne), respectively. The analytical expression for the current-voltage behavior of the coupled photodiode-electrocatalyst device (αA = αC = 0.5) and an isolated photodiode is plotted, compared, and augmented with band diagrams at equilibrium, open circuit, short circuit, and the maximum power point to illustrate the effect of coupling an electrocatalyst to a photodiode. The applicability of the derived equations is then demonstrated by comparing with a recently reported high efficiency, thin film InP/InOxPy/Rh photoelectrosynthetic hydrogen evolution device.
Design and performance of an ultra-high vacuum scanning tunneling microscope operating at dilution refrigerator temperatures and high magnetic fields
Authors: Misra S. , Zhou B. B. , Drozdov I. K. , Seo J. , Urban L. , Gyenis A. , Kingsley S. C. J. , Jones H. , Yazdani A.
Published: October 2013

We describe the construction and performance of a scanning tunneling microscope capable of taking maps of the tunneling density of states with sub-atomic spatial resolution at dilution refrigerator temperatures and high (14 T) magnetic fields. The fully ultra-high vacuum system features visual access to a two-sample microscope stage at the end of a bottom-loading dilution refrigerator, which facilitates the transfer of in situ prepared tips and samples. The two-sample stage enables location of the best area of the sample under study and extends the experiment lifetime. The successful thermal anchoring of the microscope, described in detail, is confirmed through a base temperature reading of 20 mK, along with a measured electron temperature of 250 mK. Atomically resolved images, along with complementary vibration measurements, are presented to confirm the effectiveness of the vibration isolation scheme in this instrument. Finally, we demonstrate that the microscope is capable of the same level of performance as typical machines with more modest refrigeration by measuring spectroscopic maps at base temperature both at zero field and in an applied magnetic field.
Challenges to the concept of an intermediate band in InAs/GaAs quantum dot solar cells
Authors: Li Tian , Bartolo Robert E. , Dagenais Mario
Published: October 2013

An InAs/GaAs quantum dot (QD) solar cell was compared to a similar bulk GaAs p-i-n structure. A 5% increase of the photocurrent was measured in the QD solar cell under Global Air Mass 1.5 condition, accompanied by a smaller value of the open circuit voltage (0.765 V) as compared with the reference GaAs device (0.922 V). The enhanced Urbach tail absorption in QD device greatly contributes to the photocurrent measured below the bandgap. This tail extension also explains the decrease in open circuit voltage in the device and makes it difficult to realize the concept of intermediate band solar cell at room temperature.
Research Updates: The three M's (materials, metrology, and modeling) together pave the path to future nanoelectronic technologies
Authors: King Sean W. , Simka Harsono , Herr Dan , Akinaga Hiro , Garner Mike
Published: October 2013

Recent discussions concerning the continuation of Moore's law have focused on announcements by several major corporations to transition from traditional 2D planar to new 3D multi-gate field effect transistor devices. However, the growth and progression of the semiconductor microelectronics industry over the previous 4 decades has been largely driven by combined advances in new materials, lithography, and materials related process technologies. Looking forward, it is therefore anticipated that new materials and materials technologies will continue to play a significant role in both the pursuit of Moore's law and the evolution of the industry. In this research update, we discuss and illustrate some of the required and anticipated materials innovations that could potentially lead to the continuation of Moore's law for another decade (or more). We focus primarily on the innovations needed to achieve single digit nanometer technologies and illustrate how at these dimensions not only new materials but new metrologies and computational modeling will be needed.