bluuebunny/crossref_metadata_2025 huggingface dataset:
In silico concurrent multisite pH titration in proteins
Authors: Hu Hao , Shen Lin
Published: June 2014

The concurrent proton binding at multiple sites in macromolecules such as proteins and nucleic acids is an important yet challenging problem in biochemistry. We develop an efficient generalized Hamiltonian approach to attack this issue. Based on the previously developed generalized‐ensemble methods, an effective potential energy is constructed which combines the contributions of all (relevant) protonation states of the molecule. The effective potential preserves important phase regions of all states and, thus, allows efficient sampling of these regions in one simulation. The need for intermediate states in alchemical free energy simulations is greatly reduced. Free energy differences between different protonation states can be determined accurately and enable one to construct the grand canonical partition function. Therefore, the complicated concurrent multisite proton titration process of protein molecules can be satisfactorily simulated. Application of this method to the simulation of the pKa of Glu49, Asp50, and C‐terminus of bovine pancreatic trypsin inhibitor shows reasonably good agreement with published experimental work. This method provides an unprecedented vivid picture of how different protonation states change their relative population upon pH titration. We believe that the method will be very useful in deciphering the molecular mechanism of pH‐dependent biomolecular processes in terms of a detailed atomistic description. © 2014 Wiley Periodicals, Inc.
Homeostasis and secretion of calcium in the oviductal mucosa of toad Rhinella arenarum
Authors: Crespo Claudia A. , Medina Marcela F. , Ramos Inés , Fernández Silvia N.
Published: June 2014

The presence of a calcium pump, calbindin D‐28KD, and calmodulin in the secretory cells (SC) of the oviductal pars convoluta (PC) of Rhinella arenarum was established for the first time in amphibians using immunohistochemical techniques. Marked variations were observed in the localization and degree of expression of these proteins according to the duct segment and the period of the sexual cycle analyzed. During the preovulatory and ovulatory periods the calcium pump colocalized with calbindin D‐28KD can be seen mainly in the apical border of the SC, which are located in the first zones of PC and synthesize and secrete the components of the inner jelly coat layers. These envelopes, which surround the oocytes, contain the molecules indispensable for fertilization, probably inducing the sperm acrosome reaction (AR). Our results suggest that calmodulin, colocalized with the calcium pump at the SC cytoplasmic level, would be involved in the active transport of the cation inside the secretory granules, maintaining adequate levels of intracellular Ca2+. During the postreproductive period, a calcium pump colocalized with calbindin D‐28KD appears for the first time in the cycle in the basal zones of the SC. This system may be related to the replenishing of intracellular Ca2+ stores. In contrast, in R. arenarum the Ca2+ present in the jelly coats that surround the oocytes participates in the AR during fertilization, suggesting that this secretion system of the cation provided by the oviductal mucosa is functionally more active during the reproductive period of this species. J. Exp. Zool. 321A: 432–441, 2014. © 2014 Wiley Periodicals, Inc.
Chemistry of Phosphorus Ylides. Part 40. Synthesis of Pyrazoles by the [3 + 2] Cycloaddition of Diazo Compounds with Wittig Reagents as Antimicrobial Compounds
Authors: Maigali Soher S. , Abd‐El‐Maksoud Mansoura A. , Soliman Fouad M. , Moharam Mysa E.
Published: June 2014

A comparative study between the reactions of active phosphacumulenes and stabilized phosphonium ylides on some diazo compounds have been performed. A number of substituted phosphanylidene spiro pyrazoles have been synthesized from the reaction of the active phosphacumulenes and the diazo derivatives. On the other hand, treatment of the diazo substrates with the stabilized phosphonium ylides led to the formation of the corresponding ylidenes and diazenyl phosphanylidenes. The antimicrobial activities for the new compounds are also reported.
High Power Femtosecond Lasers
Authors: Mans Torsten , Dolkemeyer Jan , Schnitzler Claus
Published: June 2014

The InnoSlab concept was developed at Fraunhofer ILT more than 15 years ago using Nd‐based laser crystals. InnoSlab is a highly efficient amplification setup that allows for an extremely broad range of laser parameters due to its inherently simple setup. Today InnoSlab using Yb‐based laser crystals is the leading amplifier technology for achieving highest output power in the ultrashort pulse regime.
Sapphire Cutting with Pulsed Fiber Lasers
Authors: Rüttimann Christoph
Published: June 2014

Sapphire cutting is currently one of the largest emerging markets in laser materials processing. Sapphire is one of the hardest existing transparent materials. Its mechanical and optical properties made it the ideal and precious choice for various components like cover glasses of watches, displays of mobile devices, protection windows for cameras, or LED carriers. Sapphire cutting with solid state lasers (e. g. lamp‐pumped solid state lasers) is well known since many years and has become a state‐of‐the‐art industrial process. However, achievable process speed and cut quality are limited, and running costs are relatively high. Recent advances in fiber laser, as well as short and ultra‐short pulsed laser technology have brought the sapphire cutting process to a new level of performance. Cutting speed and quality can be significantly improved at lower running costs.
Heterogenization of an Anilinonaphthoquinone‐Chelated Nickel Complex for Ethylene Polymerization Using Silica‐Supported Modified Methylaluminoxane
Authors: Okada Mitsuhiro , Nakayama Yuushou , Shiono Takeshi
Published: June 2014

An anilinonaphthoquinone‐ligated nickel complex [Ni(C10H5O2NC6H3–2,6‐iPr2)(Ph)(PPh3)] (1) activated with silica‐supported modified methylaluminoxane is found to be effective for ethylene polymerization under atmospheric pressure at low Al/Ni ratio. The activity of this system becomes maximal at 60 °C with a steady polymerization rate. The molecular weight of the produced polymer monotonously decreases with raising polymerization temperature, but the high‐molecularweight polymer with the number‐average molecular weight of 119 000 g mol−1 is obtained even at 80 °C. The produced polymer possesses methyl branches, the content of which is increased by raising the polymerization temperature. Consequently, the melting point of the produced polymer decreases from 130 to 120 °C by raising the polymerization temperature from 40 to 80 °C.

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Vanadyl Di(5‐t‐butyl‐2‐(aryliminomethyl)quinolin‐8‐olate): Synthesis, Characterization, and Ethylene (Co‐)Polymerization
Authors: Yan Qing , Sun Zelin , Zhang Wenjuan , Nomura Kotohiro , Sun Wen‐Hua
Published: June 2014

A series of vanadyl di(5‐t‐butyl‐2‐(aryliminomethyl)quinolin‐8‐olate) complexes is prepared by the reaction of 5‐t‐butyl‐2‐(aryliminomethyl)quinolin‐8‐ol derivatives with a slight excess of VO(OPr)3 in toluene. All the vanadyl complexes are fully characterized by elemental analysis and FTIR spectroscopy; moreover, the molecular structures of representative complexes C2 and C3 are further confirmed by single‐crystal X‐ray diffraction. On activation with diethyl­aluminum chloride (Et2AlCl) in either the presence or absence of ethyl trichloroacetate (ETA), all the vanadyl complexes exhibit high activities toward ethylene polymerization (up to 1.81 × 107 g mol−1 V h−1), producing polyethylenes with ultrahigh molecular weights (up to 1.51 × 106 g mol−1) and narrow polydispersities. The copolymerizations of ethylene with either norbornene or 1‐hexene are also successfully carried out with high activities.

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Acceleration and Selective Monomer Addition during Aqueous RAFT Copolymerization of Ionic Monomers at 25 °C
Authors: Li Guangxiang , Xu Na , Yu Qiuping , Lu Xinhua , Chen Hong , Cai Yuanli
Published: June 2014

An acceleration effect and selective monomer addition during RAFT copolymerization of the oppositely‐charged ionic monomers in dilute aqueous solution at 25 °C are reported. The reaction is conducted using a non‐ionic water‐soluble polymer as a macromolecular chain transfer agent under visible light irradiation. A fast iterative polymerization can be induced, even in dilute solution, by the favorable ionic interactions and in situ self‐assembly of zwitterionic growing chains. Selelctive monomer addition is achieved in the statistical copolymerization due to the ion‐pairing of the oppositely‐charged monomers, such as precisely the same reaction rates at a 1:1 of monomer ratio, otherwise a faster reaction of the minor monomer component over the major one. These behaviors open up an avenue towards the rapid synthesis of sequence‐controlled zwitterionic polyelectrolytes that can satisfy the demands of emerging biological applications.

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Software eyes for protein post‐translational modifications
Authors: Na Seungjin , Paek Eunok
Published: June 2014

Post‐translational modifications (PTMs) are critical to almost all aspects of complex processes of the cell. Identification of PTMs is one of the biggest challenges for proteomics, and there have been many computational studies for the analysis of PTMs from tandem mass spectrometry (MS/MS). Most early PTM identification studies have been performed by matching MS/MS data to protein databases, using database search tools, but they are prohibitively slow when a large number of PTMs is given as a search parameter. In this article, we present recent developments to search for more types of PTMs and to speed up the search, and discuss many computational issues and solutions in terms of identifying multiply modified peptides or searching for all possible modifications at once in unrestrictive mode. Apart from the most common type of PTMs involving covalent addition of functional groups to proteins, PTMs such as disulfide linkage require dedicated software for the analysis because they may involve cross‐linking between two different parts of proteins. Finally, methods for identification of protein disulfide bonds are presented. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 34: 133–147, 2015.
Mass spectrometric analysis of protein tyrosine nitration in aging and neurodegenerative diseases
Authors: Yeo Woon‐Seok , Kim Young Jun , Kabir Mohammad Humayun , Kang Jeong Won , Kim Kwang Pyo
Published: June 2014

This review highlights the significance of protein tyrosine nitration (PTN) in signal transduction pathways, the progress achieved in analytical methods, and the implication of nitration in the cellular pathophysiology of aging and age‐related neurodegenerative diseases. Although mass spectrometry of nitrated peptides has become a powerful tool for the characterization of nitrated peptides, the low stoichiometry of this modification clearly necessitates the use of affinity chromatography to enrich modified peptides. Analysis of nitropeptides involves identification of endogenous, intact modification as well as chemical conversion of the nitro group to a chemically reactive amine group and further modifications that enable affinity capture and enhance detectability by altering molecular properties. In this review, we focus on the recent progress in chemical derivatization of nitropeptides for enrichment and mass analysis, and for detection and quantification using various analytical tools. PTN participates in physiological processes, such as aging and neurodegenerative diseases. Accumulation of 3‐nitrotyrosine has been found to occur during the aging process; this was identified through mass spectrometry. Further, there are several studies implicating the presence of nitrated tyrosine in age‐related diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 34: 166–183, 2015.
Advanced mass spectrometry‐based multi‐omics technologies for exploring the pathogenesis of hepatocellular carcinoma
Authors: Nie Wenna , Yan Leyu , Lee Yie H. , Guha Chandan , Kurland Irwin J. , Lu Haitao
Published: June 2014

Hepatocellular carcinoma (HCC) is one of the primary hepatic malignancies and is the third most common cause of cancer related death worldwide. Although a wealth of knowledge has been gained concerning the initiation and progression of HCC over the last half century, efforts to improve our understanding of its pathogenesis at a molecular level are still greatly needed, to enable clinicians to enhance the standards of the current diagnosis and treatment of HCC. In the post‐genome era, advanced mass spectrometry driven multi‐omics technologies (e.g., profiling of DNA damage adducts, RNA modification profiling, proteomics, and metabolomics) stand at the interface between chemistry and biology, and have yielded valuable outcomes from the study of a diversity of complicated diseases. Particularly, these technologies are being broadly used to dissect various biological aspects of HCC with the purpose of biomarker discovery, interrogating pathogenesis as well as for therapeutic discovery. This proof of knowledge‐based critical review aims at exploring the selected applications of those defined omics technologies in the HCC niche with an emphasis on translational applications driven by advanced mass spectrometry, toward the specific clinical use for HCC patients. This approach will enable the biomedical community, through both basic research and the clinical sciences, to enhance the applicability of mass spectrometry‐based omics technologies in dissecting the pathogenesis of HCC and could lead to novel therapeutic discoveries for HCC. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 35:331–349, 2016.
Models for Self‐Avoiding Polymer Chains on the Tetrahedral Lattice
Authors: Dietschreit Johannes , Diestler Dennis J. , Knapp Ernst‐Walter
Published: June 2014

A hierarchy of models for self‐avoiding polymer chains on the tetrahedral lattice is introduced. The chain comprises a concatenation of identical atoms. The models (SAWn), are characterized by the degree of self‐avoidance (specified by the integer n), which is controlled by systematic variation of the closest distance allowed between atom pairs that are not covalently bonded. SAW1, possessing the lowest degree of self‐avoidance, is the simple self‐avoidance model (i.e., no two atoms of the chain occupy the same site) that has been routinely employed in studies of fundamental phenomena. The results of Monte Carlo calculations are presented that show the influence of n on such properties of the chain as Flory radius, distribution of dihedral angles, and entropy loss due to self avoidance. Algorithms are developed that allow the efficient generation of large ensembles of chain conformations, which are necessary especially for a reliable calculation of the entropy loss induced by self‐avoidance.
Genomovar assignment of Pseudomonas stutzeri populations inhabiting produced oil reservoirs
Authors: Zhang Fan , She Yue‐Hui , Banat Ibrahim M. , Chai Lu‐Jun , Huang Liu‐Qin , Yi Shao‐Jin , Wang Zheng‐Liang , Dong Hai‐Liang , Hou Du‐Jie
Published: June 2014

Oil reservoirs are specific habitats for the survival and growth of microorganisms in general. Pseudomonas stutzeri which is believed to be an exogenous organism inoculated into oil reservoirs during the process of oil production was detected frequently in samples from oil reservoirs. Very little is known, however, about the distribution and genetic structure of P. stutzeri in the special environment of oil reservoirs. In this study, we collected 59 P. stutzeri 16S rRNA gene sequences that were identified in 42 samples from 25 different oil reservoirs and we isolated 11 cultured strains from two representative oil reservoirs aiming to analyze the diversity and genomovar assignment of the species in oil reservoirs. High diversity of P. stutzeri was observed, which was exemplified in the detection of sequences assigned to four known genomovars 1, 2, 3, 20 and eight unknown genomic groups of P. stutzeri. The frequent detection and predominance of strains belonging to genomovar 1 in most of the oil reservoirs under study indicated an association of genomovars of P. stutzeri with the oil field environments.
Is Sodium Valproate, an HDAC inhibitor, associated with reduced risk of stroke and myocardial infarction? A nested case–control study
Authors: Dregan Alex , Charlton Judith , Wolfe Charles D. A. , Gulliford Martin C. , Markus Hugh S.
Published: June 2014

Background

This study aimed to evaluate whether treatment with sodium valproate (SV) was associated with reduced risk of stroke or myocardial infarction (MI).

Methods

Electronic health records data were extracted from Clinical Practice Research Database for participants ever diagnosed with epilepsy and prescribed antiepileptic drugs. A nested case–control study was implemented with cases diagnosed with incident non‐haemorrhagic stroke and controls matched for sex, year of birth, and study start date (ratio of 1:6). A second nested study was implemented with MI as outcome. The main exposure variable was SV therapy assessed as: ever prescribed, pre‐stroke year treatment, number of SV prescriptions, and cumulative time on SV drug therapy. Odds ratios were estimated using conditional logistic regression.

Results

Data were analysed for 2002 stroke cases and 13 098 controls. MI analyses included 1153 cases and 7109 controls. Pre‐year stroke SV treatment (28%) was associated with increased stroke risk (odds ratio 1.22, 95% confidence interval (CI): 1.09 to 1.38, p < 0.001). No association was observed between ever being prescribed SV with ischemic stroke (OR = 1.01, 95% CI: 0.91 to 1.12, p = 0.875). A significant association was observed between ever being prescribed SV with MI (OR = 0.78, 95% CI: 0.67 to 0.90, p < 0.001). Patients in the highest quarter of SV treatment duration had lower odds of ischemic stroke (OR = 0.57, 95% CI: 0.44 to 0.72, p < 0.001) and MI (OR = 0.29, 95% CI: 0.20 to 0.44, p < 0.001).

Conclusion

Sodium valproate exposure was associated with the risk of MI, but not ischemic stroke. However, longer exposure to SV was associated with lower odds of stroke, but this might be explained by survivor bias. © 2014 The Authors. Pharmacoepidemiology and Drug Safety published by John Wiley & Sons, Ltd.
Assessment of photovoltaic junction position using combined focused ion beam and electron beam‐induced current analysis of close space sublimation deposited CdTe solar cells
Authors: Major Jonathan Douglas , Bowen Leon , Treharne Robert , Durose Ken
Published: June 2014

A major limitation of the cross‐section electron beam‐induced current method—the use of roughly fractured surfaces to provide the cross‐section—has been overcome with the use of focused ion beam microscope sample preparation. Using this method, it was possible to undertake a study of the relation between junction position and the corresponding external quantum efficiency (EQE) curves. For the case of cadmium telluride (CdTe) cells, it was demonstrated that the EQE curve shape that indicates a buried CdTe homojunction only arises if the junction is buried by more than 0.9 µm from the heterointerface. This highlights the limitations of interpreting EQE curve shape to determine junction position. It was also shown that extended postgrowth annealing degrades the cadmium sulfide by Kirkendall voiding, and this leads to efficiency loss. © 2014 The Authors. Progress in Photovoltaics: Research and Applications published by John Wiley & Sons, Ltd.
Intolerance of uncertainty, cognitive complaints, and cancer‐related distress in prostate cancer survivors
Authors: Eisenberg Stacy A. , Kurita Keiko , Taylor‐Ford Megan , Agus David B. , Gross Mitchell E. , Meyerowitz Beth E.
Published: June 2014

Objective

Prostate cancer survivors have reported cognitive complaints following treatment, and these difficulties may be associated with survivors' ongoing cancer‐related distress. Intolerance of uncertainty may exacerbate this hypothesized relationship by predisposing individuals to approach uncertain situations such as cancer survivorship in an inflexible and negative manner.

We investigated whether greater cognitive complaints and higher intolerance of uncertainty would interact in their relation to more cancer‐related distress symptoms.

Methods

This cross‐sectional, questionnaire‐based study included 67 prostate cancer survivors who were 3 to 5 years post treatment. Hierarchical multiple regression analyses tested the extent to which intolerance of uncertainty, cognitive complaints, and their interaction were associated with cancer‐related distress (measured with the Impact of Event Scale‐Revised; IES‐R) after adjusting for age, education, physical symptoms, and fear of cancer recurrence.

Results

Intolerance of uncertainty was positively associated with the IES‐R avoidance and hyperarousal subscales. More cognitive complaints were associated with higher scores on the IES‐R hyperarousal subscale. The interaction of intolerance of uncertainty and cognitive complaints was significantly associated with IES‐R intrusion, such that greater cognitive complaints were associated with greater intrusive thoughts in survivors high in intolerance of uncertainty but not those low in it.

Conclusions

Prostate cancer survivors who report cognitive difficulties or who find uncertainty uncomfortable and unacceptable may be at greater risk for cancer‐related distress, even 3 to 5 years after completing treatment. It may be beneficial to address both cognitive complaints and intolerance of uncertainty in psychosocial interventions. Copyright © 2014 John Wiley & Sons, Ltd.
Management based on exhaled nitric oxide levels adjusted for atopy reduces asthma exacerbations in children: A dual centre randomized controlled trial
Authors: Petsky Helen L. , Li Albert M. , Au Chun T. , Kynaston Jennifer A. , Turner Catherine , Chang Anne B.
Published: June 2014

While several randomized control trials (RCTs) have evaluated the use of fractional exhaled nitric oxide (FeNO) to improve asthma outcomes, none used FeNO cut‐offs adjusted for atopy, a determinant of FeNO levels. In a dual center RCT, we assessed whether a treatment strategy based on FeNO levels, adjusted for atopy, reduces asthma exacerbations compared with the symptoms‐based management (controls). Children with asthma from hospital clinics of two hospitals were randomly allocated to receive an a‐priori determined treatment hierarchy based on symptoms or FeNO levels. There was a 2‐week run‐in period and they were then reviewed 10 times over 12‐months. The primary outcome was the number of children with exacerbations over 12‐months. Sixty‐three children were randomized (FeNO = 31, controls = 32); 55 (86%) completed the study. Although we did achieve our planned sample size, significantly fewer children in the FeNO group (6 of 27) had an asthma exacerbation compared to controls (15 of 28), P = 0.021; number to treat for benefit = 4 (95% CI 3–24). There was no difference between groups for any secondary outcomes (quality of life, symptoms, FEV1). The final daily inhaled corticosteroids (ICS) dose was significantly (P = 0.037) higher in the FeNO group (median 400 µg, IQR 250–600) compared to the controls (200, IQR100–400). Taking atopy into account when using FeNO to tailor asthma medications is likely beneficial in reducing the number of children with severe exacerbations at the expense of increased ICS use. However, the strategy is unlikely beneficial for improving asthma control. A larger study is required to confirm or refute our findings. Pediatr Pulmonol. 2015; 50:535–543. © 2014 Wiley Periodicals, Inc.
Recent developments in the type IIB matrix model
Authors: Nishimura J.
Published: June 2014

We review recent developments in the type IIB matrix model, which was conjectured to be a nonperturbative formulation of superstring theory. In the first part we review the recent results for the Euclidean model, which suggest that SO(10) symmetry is spontaneously broken. In the second part we review the recent results for the Lorentzian model. In particular, we discuss Monte Carlo results, which suggest that (3+1)‐dimensional expanding universe emerges dynamically. We also discuss some results suggesting the emergence of exponential expansion and the power‐law expansion at later times. The behaviors at much later times are studied by the classical equation of motion. We discuss a solution representing 3d expanding space, which suggests a possible solution to the cosmological constant problem.
Are human polyomaviruses co‐factors for cancers induced by other oncoviruses?
Authors: Moens Ugo , Van Ghelue Marijke , Ehlers Bernhard
Published: June 2014

Presently, 12 human polyomaviruses are known: BK polyomavirus (BKPyV), JCPyV, KIPyV, WUPyV, Merkel cell polyomavirus (MCPyV), HPyV6, HPyV7, Trichodysplasia spinulosa‐associated polyomavirus, HPyV9, HPyV10, STLPyV and HPyV12. In addition, the non‐human primate polyomavirus simian virus 40 (SV40) seems to circulate in the human population. MCPyV was first described in 2008 and is now accepted to be an etiological factor in about 80% of the rare but aggressive skin cancer Merkel cell carcinoma. SV40, BKPyV and JCPyV or part of their genomes can transform cells, including human cells, and induce tumours in animal models. Moreover, DNA and RNA sequences and proteins of these three viruses have been discovered in tumour tissue. Despite these observations, their role in cancer remains controversial. So far, an association between cancer and the other human polyomaviruses is lacking. Because human polyomavirus DNA has been found in a broad spectrum of cell types, simultaneous dwelling with other oncogenic viruses is possible. Co‐infecting human polyomaviruses may therefore act as a co‐factor in the development of cancer, including those induced by other oncoviruses. Reviewing studies that report co‐infection with human polyomaviruses and other tumour viruses in cancer tissue fail to detect a clear link between co‐infection and cancer. Directions for future studies to elaborate on a possible auxiliary role of human polyomaviruses in cancer are suggested, and the mechanisms by which human polyomaviruses may synergize with other viruses in oncogenic transformation are discussed. Copyright © 2014 John Wiley & Sons, Ltd.
Finite‐time stability of fractional order impulsive switched systems
Authors: Yang Ying , Chen Guopei
Published: June 2014

This paper considers the finite‐time stability of fractional order impulsive switched systems. First, by using the fractional order Lyapunov function, Mittag–Leffler function, and Gronwall–Bellman lemma, two sufficient conditions are given to verify the finite‐time stability of fractional order nonlinear systems. Then, the concept of finite‐time stability is extended to fractional order impulsive switched systems. A sufficient condition is given to verify the finite‐time stability of fractional order impulsive switched systems by combining the method of average dwell time with fractional order Lyapunov function. Finally, two numerical examples are provided to illustrate the theoretical results. Copyright © 2014 John Wiley & Sons, Ltd.
A new asymmetric Pseudo‐Voigt function for more efficient fitting of XPS lines
Authors: Schmid Martin , Steinrück Hans‐Peter , Gottfried J. Michael
Published: June 2014

Asymmetric peak profiles for the application in spectroscopy can be obtained in a simple way by substituting the usually constant full width at half maximum parameter in Pseudo‐Voigt functions with an energy‐dependent expression, for instance of sigmoidal shape. While this approach has been successfully applied to vibrational spectra, we find that the resulting curves are less suitable for least‐squares fits of X‐ray photoelectron spectroscopy (XPS) data. However, if one additionally allows a variable displacement of the sigmoidal step relative to the peak, excellent fitting results can be obtained. We demonstrate the applicability of our extended approach on several inherently asymmetric XPS lines, i.e. the C 1s signal of graphite and C2H2/Pd(100), the 3d5/2–3d3/2 doublet of palladium, and the 4f7/2–4f5/2 doublet of platinum. Comparison of the corresponding fit results with the results obtained by the application of more elaborate, theory‐based line profiles (Doniach‐Šunjić and Mahan functions) shows that the modified Pseudo‐Voigt function gives practically identical results in terms of peak shape and area, while requiring much less computational effort since no convolution procedures are required for its calculation. Thus, this function is most suitable for application in one of the following situations: (i) the peak shape of a given signal is known but cannot be calculated with ease, and (ii) the theoretical peak shape is not (yet) known, however, one wants to perform a first quantitative screening of the data at issue. Copyright © 2014 John Wiley & Sons, Ltd.
Identification of nano clay in composite polymers
Authors: Tentschert Jutta , Jungnickel Harald , Reichardt Philipp , Leube Peter , Kretzschmar Bernd , Taubert A. , Luch A.
Published: June 2014

Industrialized food production is in urgent search for alternative packaging materials, which can serve the requirements of a globalized world in terms of longer product shelf lives, reduced freight weight to decrease transport costs, and better barrier functionality to preserve its freshness. Polymer materials containing organically modified nano clay particles as additives are one example for a new generation of packaging materials with specific barrier functionality to actually hit the market. Clay types used for these applications are aluminosilicates, which belong to the mineral group of phyllosilicates. These consist of nano‐scaled thin platelets, which are organically modified with quaternary ammonium compounds acting as spacers between the different clay layers, thereby increasing the hydrophobicity of the mineral additive. A variety of different organically modified clays are already available, and the use as additive for food packaging materials is one important application. To ensure valid risk assessments of emerging nano composite polymers used in the food packaging industry, exact analytical characterization of the organically modified clay within the polymer matrix is of paramount importance. Time‐of‐flight SIMS in combination with multivariate statistical analysis was used to differentiate modified clay reference materials from another. Time‐of‐flight SIMS spectra of a reference polymer plate, which contained one specific nano clay composite, were acquired. For each modified clay additive, a set of characteristic diagnostic ions could be identified, which then was used to successfully assign unknown clay additives to the corresponding reference material. Thus, the described methodology could be used to define and characterize nano clay within polymer matrices. Copyright © 2014 John Wiley & Sons, Ltd.
Historical, Philosophical, and Practical Issues in Providing Global Learning Opportunities Through Study Abroad
Authors: Rhodes Gary , Loberg Lisa , Hubbard Ann
Published: June 2014

This chapter provides a historical and practical background on the evolution and responsibilities of administering study abroad programs for U.S. college and university students.
Empowering Faculty to Develop and Share Global Knowledge
Authors: Harrison David
Published: June 2014

As colleges seek to increase global knowledge within its students, it is important that faculty members are also offered opportunities to increase their own knowledge of global issues. This chapter discusses faculty development models for seminars abroad and how these seminars encourage the development of unique global study programs.
The Impact of International Internships and Short‐Term Immersion Programs
Authors: Gates Lisa
Published: June 2014

For students in U.S. higher education institutions, global learning through study abroad has become a powerful force in student cultural competence. This chapter explores the impact of international internships and other short‐term immersion experiences in further developing student learning, especially with respect to their understanding of the importance of global issues for their academic trajectories and future careers.
Predeparture Services for Students Studying Abroad
Authors: Highum Ann
Published: June 2014

This chapter discusses aspects of preparation for students who will study abroad, suggests topics that should be covered, and speaks to issues involved with cultural immersion.
The Role of the Dean of Students in Study Abroad
Authors: Rader Matthew S.
Published: June 2014

This chapter provides an overview of key concepts a senior student affairs officer should take into account with students studying overseas. The importance of partnerships with on‐campus offices is also discussed.
Outcomes of Global Education: External and Internal Change Associated With Study Abroad
Authors: Miller‐Perrin Cindy , Thompson Don
Published: June 2014

This chapter provides an overview of external and internal changes associated with collegiate study abroad experiences. A brief review of the research literature is included along with recent research that sheds light on potential mechanisms associated with study abroad–related change. Recommendations for enhancing outcomes associated with study abroad are also provided.
The Defective Armchair: A Reply to Tye
Authors: Block Ned ,   Philosophy Documentation Center
Published: June 2014

Michael Tye’s response to my “Grain” (Block 2012) and “Windows” (Block 2013) raises general metaphilosophical issues about the value of intuitions and judgments about one’s perceptions and the relations of those intuitions and judgments to empirical research, as well as specific philosophical issues about the relation between seeing, attention and de re thought. I will argue that Tye’s appeal to what is (§. 2) “intuitively obvious, once we reflect upon these cases” (“intuition”) is problematic. I will also argue that first person judgments can be problematic when used on their own as Tye does but can be valuable when integrated with empirical results.
Controlled ocular drug delivery with nanomicelles
Authors: Vaishya Ravi D. , Khurana Varun , Patel Sulabh , Mitra Ashim K.
Published: June 2014

Many vision threatening ocular diseases such as age‐related macular degeneration (AMD), diabetic retinopathy, glaucoma, and proliferative vitreoretinopathy may result in blindness. Ocular drug delivery specifically to the intraocular tissues remains a challenging task due to the presence of various physiological barriers. Nonetheless, recent advancements in the field of nanomicelle‐based novel drug delivery system could fulfil these unmet needs. Nanomicelles consists of amphiphilic molecules that self‐assemble in aqueous media to form organized supramolecular structures. Micelles can be prepared in various sizes (10–1000 nm) and shapes depending on the molecular weights of the core and corona forming blocks. Nanomicelles have been an attractive carrier for their potential to solubilize hydrophobic molecules in aqueous solution. In addition, small size in nanometer range and highly modifiable surface properties have been reported to be advantageous in ocular drug delivery. In this review, various factors influencing rationale design of nanomicelles formulation and disposition are discussed along with case studies. Despite the progress in the field, influence of various properties of nanomicelles such as size, shape, surface charge, rigidity of structure on ocular disposition need to be studied in further details to develop an efficient nanocarrier system.

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies
Expression and evaluation of enzymes required for the hydrolysis of galactomannan
Authors: Malherbe A R , Rose S H , Viljoen-Bloom M , van Zyl W H
Published: June 2014

The cost-effective production of bioethanol from lignocellulose requires the complete conversion of plant biomass, which contains up to 30 % mannan. To ensure utilisation of galactomannan during consolidated bioprocessing, heterologous production of mannan-degrading enzymes in fungal hosts was explored. The Aspergillus aculeatus endo-β-mannanase (Man1) and Talaromyces emersonii α-galactosidase (Agal) genes were expressed in Saccharomyces cerevisiae Y294, and the Aspergillus niger β-mannosidase (cMndA) and synthetic Cellvibrio mixtus β-mannosidase (Man5A) genes in A. niger. Maximum enzyme activity for Man1 (374 nkat ml−1, pH 5.47), Agal (135 nkat ml−1, pH 2.37), cMndA (12 nkat ml−1, pH 3.40) and Man5A (8 nkat ml−1, pH 3.40) was observed between 60 and 70 °C. Co-expression of the Man1 and Agal genes in S. cerevisiae Y294[Agal-Man1] reduced the extracellular activity relative to individual expression of the respective genes. However, the combined action of crude Man1, Agal and Man5A enzyme preparations significantly decreased the viscosity of galactomannan in locust bean gum, confirming hydrolysis thereof. Furthermore, when complemented with exogenous Man5A, S. cerevisiae Y294[Agal-Man1] produced 56 % of the theoretical ethanol yield, corresponding to a 66 % carbohydrate conversion, on 5 g l−1 mannose and 10 g l−1 locust bean gum.
Aging in the Context of Cohort Evolution and Mortality Selection
Authors: Zheng Hui
Published: June 2014

This study examines historical patterns of aging through the perspectives of cohort evolution and mortality selection, where the former emphasizes the correlation across cohorts in the age dependence of mortality rates, and the latter emphasizes cohort change in the acceleration of mortality over the life course. In the analysis of historical cohort mortality data, I find support for both perspectives. The rate of demographic aging, or the rate at which mortality accelerates past age 70, is not fixed across cohorts; rather, it is affected by the extent of mortality selection at young and late ages. This causes later cohorts to have higher rates of demographic aging than earlier cohorts. The rate of biological aging, approximating the rate of the senescence process, significantly declined between the mid- and late-nineteenth century birth cohorts and stabilized afterward. Unlike the rate of demographic aging, the rate of biological aging is not affected by mortality selection earlier in the life course but rather by cross-cohort changes in young-age mortality, which cause lower rates of biological aging in old age among later cohorts. These findings enrich theories of cohort evolution and have implications for the study of limits on the human lifespan and evolution of aging.
Structural and degradative aspects of ornithine decarboxylase antizyme inhibitor 2
Authors: Ramos-Molina Bruno , Lambertos Ana , Lopez-Contreras Andrés J. , Kasprzak Joanna M. , Czerwoniec Anna , Bujnicki Janusz M. , Cremades Asunción , Peñafiel Rafael
Published: June 2014

Ornithine decarboxylase (ODC) is the key enzyme in the polyamine biosynthetic pathway. ODC levels are controlled by polyamines through the induction of antizymes (AZs), small proteins that inhibit ODC and target it to proteasomal degradation without ubiquitination. Antizyme inhibitors (AZIN1 and AZIN2) are proteins homologous to ODC that bind to AZs and counteract their negative effect on ODC. Whereas ODC and AZIN1 are well‐characterized proteins, little is known on the structure and stability of AZIN2, the lastly discovered member of this regulatory circuit. In this work we first analyzed structural aspects of AZIN2 by combining biochemical and computational approaches. We demonstrated that AZIN2, in contrast to ODC, does not form homodimers, although the predicted tertiary structure of the AZIN2 monomer was similar to that of ODC. Furthermore, we identified conserved residues in the antizyme‐binding element, whose substitution drastically affected the capacity of AZIN2 to bind AZ1. On the other hand, we also found that AZIN2 is much more labile than ODC, but it is highly stabilized by its binding to AZs. Interestingly, the administration of the proteasome inhibitor MG132 caused differential effects on the three AZ‐binding proteins, having no effect on ODC, preventing the degradation of AZIN1, but unexpectedly increasing the degradation of AZIN2. Inhibitors of the lysosomal function partially prevented the effect of MG132 on AZIN2. These results suggest that the degradation of AZIN2 could be also mediated by an alternative route to that of proteasome. These findings provide new relevant information on this unique regulatory mechanism of polyamine metabolism.
An Association Study of CASQ1 Gene Polymorphisms and Heat Stroke
Authors: Li Ying , Wang Yu , Ma Lin
Published: June 2014

Although molecular mechanisms of heat stroke under physiological and pathological conditions have not yet been elucidated, a novel disease-associated gene encoding a calcium-binding protein, calsequestrin-1 (CASQ1), was suggested relevant based on results from a transgenic murine model. Here, we show the association between single nucleotide polymorphisms (SNPs) of CASQ1 and physiological parameters for heat stroke from a study involving 150 patients. Pooled DNA from heat stroke patients were subjected to sequencing and 3 SNPs were identified. Genotypes were assigned for all patients according to g. 175A>G, one SNP which leads to a nonsynonymous substitution (N59D) in the first exon of human CASQ1 gene. We analyzed the genotypic data with a linear model based on significance scores between SNP (175A>G) and heat stroke parameters. As a result, we found a significant association between SNP A175G and heat stroke (P  < 0.05). Further bioinformatics analysis of the 1-Mb flanking sequence revealed the presence of two genes that encode DDB1 and CUL4 associated factor 8 (DCAF8), and peroxisomal biogenesis factor 19 (PEX19), respectively, which might be functionally related to CASQ1. Our results showed that the blood calcium of patients with allele D increased significantly, compared to patients with allele N (P  < 0.05), which may result from the decreased calcium in muscle, suggesting that N59D in CASQ1 might account for the dysfunction of CASQ1 in calcium regulation during heat stroke.
Mouse strain and brain region‐specific expression of the glutaminyl cyclases QC and isoQC
Authors: Höfling Corinna , Indrischek Henrike , Höpcke Theodor , Waniek Alexander , Cynis Holger , Koch Birgit , Schilling Stephan , Morawski Markus , Demuth Hans‐Ulrich , Roßner Steffen , Hartlage‐Rübsamen Maike
Published: June 2014

Glutaminyl cyclases (QCs) catalyze the formation of pyroglutamate (pGlu) from glutamine precursors at the N‐terminus of a number of peptide hormones, neuropeptides and chemokines. This post‐translational modification stabilizes these peptides, protects them from proteolytical degradation or is important for their biological activity. However, QC is also involved in a pathogenic pGlu modification of peptides accumulating in protein aggregation disorders such as Alzheimer's disease and familial Danish and familial British dementia. Its isoenzyme (isoQC) was shown to contribute to aspects of inflammation by pGlu‐modifying and thereby stabilizing the monocyte chemoattractant protein CCL2. For the generation of respective animal models and for pharmacological treatment studies the characterization of the mouse strain and brain region‐specific expression of QC and isoQC is indispensible.

In order to address this issue, we used enzymatic activity assays and specific antibodies to detect both QC variants by immunohistochemistry in nine different mouse strains. Comparing different brain regions, the highest enzymatic QC/isoQC activity was detected in ventral brain, followed by cortex and hippocampus. Immunohistochemical stainings revealed that QC/isoQC activity in cortex mostly arises from isoQC expression. For most brain regions, the highest QC/isoQC activity was detected in C3H and FVB mice, whereas low QC/isoQC activity was present in CD1, SJL and C57 mice. Quantification of QC‐ and isoQC‐immunoreactive cells by unbiased stereology revealed a higher abundance of isoQC‐ than of QC‐immunoreactive neurons in Edinger–Westphal nucleus and in substantia nigra. In the locus coeruleus, however, there were comparable densities of QC‐ and of isoQC‐immunoreactive neurons.

These observations are of considerable importance with regard to the selection of appropriate mouse strains for the study of QC/isoQC relevance in mouse models of neurodegeneration and neuroinflammation and for the testing of therapeutical interventions in these models.
Environmental conditions of accumulation of Cambrian carbonaceous rocks in the Siberian Platform
Authors: Staroseltsev V.S. , Shishkin B.B.
Published: June 2014

Based on results of deep drilling and the CDP-2D seismic profiling, the relations between the Early and Middle Cambrian carbonaceous rocks and the underlying, overlying, and synchronously formed deposits in the Siberian Platform are analyzed, and the lithologo-paleogeographic, paleotectonic, and tectonic conditions of their formation are considered. It is shown that these carbonaceous rocks are intimately related to the Cambrian organogenic structures, up to their mutual transitions.
Formation mechanisms of ultradeep sedimentary basins: the North Barents basin. Petroleum potential implications
Authors: Artyushkov E.V. , Belyaev I.V. , Kazanin G.S. , Pavlov S.P. , Chekhovich P.A. , Shkarubo S.I.
Published: June 2014

Consolidated crust in the North Barents basin with sediments 16–18 km thick is attenuated approximately by two times. The normal faults in the basin basement ensure only 10–15% stretching, which caused the deposition of 2–3 km sediments during the early evolution of the basin. The overlying 16 km of sediments have accumulated since the Late Devonian. Judging by the undisturbed reflectors to a depth of 8 s, crustal subsidence was not accompanied by any significant stretching throughout that time. Dramatic subsidence under such conditions required considerable contraction of lithospheric rocks. The contraction was mainly due to high-grade metamorphism in mafic rocks in the lower crust. The metamorphism was favored by increasing pressure and temperature in the lower crust with the accumulation of a thick layer of sediments. According to gravity data, the Moho in the basin is underlain by large masses of high-velocity eclogites, which are denser than mantle peridotites. The same is typical of some other ultradeep basins: North Caspian, South Caspian, North Chukchi, and Gulf of Mexico basins. From Late Devonian to Late Jurassic, several episodes of rapid crustal subsidence took place in the North Barents basin, which is typical of large petroleum basins. The subsidence was due to metamorphism in the lower crust, when it was infiltrated by mantle-source fluids in several episodes. The metamorphic contraction in the lower crust gave rise to deep-water basins with sediments with a high content of unoxidized organic matter. Along with numerous structural and nonstructural traps in the cover of the North Barents basin, this is strong evidence that the North Barents basin is a large hydrocarbon basin.
Formation history of large anticlinal trap structures for unique gas pools in northern West Siberia (by the example of the Medvezh’e field)
Authors: Kontorovich V.A. , Kontorovich D.V. , Surikova E.S.
Published: June 2014

We consider the formation history of high-amplitude anticlinal trap structures for unique Cenomanian gas pools using the example of the Medvezh’e field. Analysis shows that the Turonian–Cenozoic was the most crucial stage of formation of the world’s largest gas-bearing province in northern West Siberia. This stage was marked by (1) the formation of large anticlinal traps—petroleum-promising objects; (2) the highest intensity of gas formation, which caused the filling of these traps; and (3) the formation of the Kuznetsov seal, which shields the giant Cenomanian gas pools.