bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation of Alfvénic waves and turbulence in reconnection jets
Authors: Hoshino Masahiro , Higashimori Katsuaki
Published: April 2015

The magnetohydrodynamic linear stability with the localized bulk flow oriented parallel to the neutral sheet is investigated, by including the Hall effect and the guide magnetic field. We observe three different unstable modes: a “streaming tearing” mode at a slow flow speed, a “streaming sausage” mode at a medium flow speed, and a “streaming kink” mode at a fast flow speed. The streaming tearing and sausage modes have a standard tearing mode‐like structure with symmetric density fluctuations in the neutral sheet, while the kink mode has an asymmetric fluctuation. The growth rate of the streaming tearing mode decreases with increasing magnetic Reynolds number, while the growth rates of the sausage and kink modes do not depend strongly on the Reynolds number. The sausage and kink modes can be unstable for not only super‐Alfvénic flow but also sub‐Alfvénic flow when the lobe density is low. The wavelengths of these unstable modes are of the same order of magnitude as the thickness of the plasma sheet. Their maximum growth rates are higher than that of a standard tearing mode, and under a strong guide magnetic field, the growth rates of the sausage and kink modes are enhanced, while under a weak guide magnetic field, they are suppressed. For a thin plasma sheet with the Hall effect, the fluctuations of the streaming modes can exist over the plasma sheet. These unstable modes may be regarded as being one of the processes generating Alfvénic turbulence in the plasma sheet during magnetic reconnection.
A general analytical solution for steady flow in heterogeneous porous media
Authors: Craig J. R.
Published: April 2015

A novel analytical solution approach for problems of steady flow in two‐dimensional heterogeneous porous media is presented, where the hydraulic conductivity may be represented as an arbitrary polynomial in space. The solution approach uses Wirtinger calculus and the Bers‐Vekua theory of elliptical functions. The final form of the solution comprises an arbitrary complex polynomial solution to the Laplace equation and additional nonholomorphic terms which are determined directly from the coefficients of this polynomial. The arbitrary polynomial coefficients may be chosen to satisfy general flow conditions along system boundaries. The approach is also extended to singular flow, such as that induced by pumping wells. The solution is demonstrated to be effectively exact for a number of test cases; the problems are solved to machine precision.
Coral reef metabolism and carbon chemistry dynamics of a coral reef flat
Authors: Albright Rebecca , Benthuysen Jessica , Cantin Neal , Caldeira Ken , Anthony Ken
Published: April 2015

Global carbon emissions continue to acidify the oceans, motivating growing concern for the ability of coral reefs to maintain net positive calcification rates. Efforts to develop robust relationships between coral reef calcification and carbonate parameters such as aragonite saturation state (Ωarag) aim to facilitate meaningful predictions of how reef calcification will change in the face of ocean acidification. Here we investigate natural trends in carbonate chemistry of a coral reef flat over diel cycles and relate these trends to benthic carbon fluxes by quantifying net community calcification and net community production. We find that, despite an apparent dependence of calcification on Ωarag seen in a simple pairwise relationship, if the dependence of net calcification on net photosynthesis is accounted for, knowing Ωarag does not add substantial explanatory value. This suggests that, over short time scales, the control of Ωarag on net calcification is weak relative to factors governing net photosynthesis.
Improved GPS‐based coseismic displacement monitoring using high‐precision oscillators
Authors: Weinbach U. , Schön S.
Published: April 2015

The determination of high‐frequency displacements using Global Navigation Satellite Systems (GNSS) observations with sampling frequencies > 1 Hz has attracted much interest in recent years, e.g., in seismology. We propose a new concept for GPS Precise Point Positioning (PPP) that takes advantage of a highly stable oscillator connected to the GPS receiver by modeling its behavior. We show that the high‐frequency noise of kinematic GPS height estimates can be reduced by a factor of up to 4 to the level of 2–3 mm and the overall standard deviation including systematic long periodic errors by a factor of up to 2 to the 1 cm level. Consequently, valuable small and currently hidden vertical displacements can be detected that are not visible with classical PPP. Using data of the 2010 Chile earthquake, we demonstrate that coseismic vertical displacements with an amplitude of only 5 mm can be recovered using PPP with the proposed clock modeling strategy.
An increase in the rate of global mean sea level rise since 2010
Authors: Yi Shuang , Sun Wenke , Heki Kosuke , Qian An
Published: May 2015

The global mean sea level (GMSL) was reported to have dropped 5 mm due to the 2010/2011 La Niña and have recovered in 1 year. With longer observations, it is shown that the GMSL went further up to a total amount of 11.6 mm by the end of 2012, excluding the 3.0 mm/yr background trend. A reconciled sea level budget, based on observations by Argo project, altimeter, and gravity satellites, reveals that the true GMSL rise has been masked by El Niño–Southern Oscillation‐related fluctuations and its rate has increased since 2010. After extracting the influence of land water storage, it is shown that the GMSL has been rising at a rate of 4.4 ± 0.5 mm/yr for more than 3 years, due to an increase in the rate of both land ice loss and steric change.
Growth of GaN on sapphire via low‐temperature deposited buffer layer and realization of p‐type GaN by Mg doping followed by low‐energy electron beam irradiation (Nobel Lecture)
Authors: Amano Hiroshi
Published: April 2015

This is a personal history of one of the Japanese researchers engaged in developing a method for growing GaN on a sapphire substrate, paving the way for the realization of smart television and display systems using blue LEDs. The most important work was done in the mid to late 1980s. The background to the author's work and the process by which the technology enabling the growth of GaN and the realization of p‐type GaN was established are reviewed.***

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Rhodium(III)‐Catalyzed ortho CH Heteroarylation of (Hetero)aromatic Carboxylic Acids: A Rapid and Concise Access to π‐Conjugated Poly‐heterocycles
Authors: Qin Xurong , Li Xiaoyu , Huang Quan , Liu Hu , Wu Di , Guo Qiang , Lan Jingbo , Wang Ruilin , You Jingsong
Published: April 2015

RhIII‐catalyzed oxidative CH/CH cross‐coupling between (hetero)aromatic carboxylic acids and various heteroarenes has been accomplished to construct highly functionalized ortho‐carboxy‐substituted bi(hetero)aryls. The use of a carboxy group as the directing group obviates tedious steps for installation and removal of extra directing groups, and enables a facile one‐step synthesis of ortho‐carboxy bi(hetero)aryls. The method provides opportunities for rapid assembly of a library of important fluorene and coumarin‐type poly‐heterocycles through intramolecular electrophilic substitution or oxidative lactonization. As illustrative examples, the strategy developed herein greatly streamlines accesses to a variety of appealing polyheterocycles such as DTPO (5H‐dithieno[3,2‐b:2′,3′‐d]pyran‐5‐one), CPDTO (cyclopentadithiophen‐4‐one), and indenothiophenes.
Biomonitoring of the Genotoxic and Hepatotoxic Effects and Oxidative Stress Potentials of Itraconazole in Pregnant Rats
Authors: El‐Shershaby Abdel‐Fattah , Dakrory Ahmed I. , El‐Dakdoky Mai H. , Ibrahim Jehane , Kassem Fatma
Published: April 2015

BACKGROUND

Pregnant women are more susceptible to both vaginal colonization and infection by yeast. One hundred million fungal infected patients have been treated worldwide with itraconazole (Caputo, 2003.

METHOD

Itraconazole was administrated orally to pregnant rats at doses of 75, 100, or 150 mg/kg during gestational days (GD) 1 to 7 or GD 8 to 14 or GD 14 to 20. The genotoxicity and hepatotoxicity of the antifungal drug itraconazole were assessed during different periods of pregnancy using different methods.

RESULTS

It was found that itraconazole was a genotoxic drug for both mothers and fetuses. This finding was observed via significant elevation in the estimated comet assay parameters (percentage of fragmented DNA, tail moment, and olive moment), percentage of fragmented DNA measured by diphenylamine assay and mixed smearing and laddering of DNA fragments of liver samples. In addition, itraconazole caused significant elevation in the level of hepatic malondialdehyde and depletion in the catalase activity and glutathione level. Furthermore, itraconazole induced histopathological alterations in the hepatic tissues of both mothers and fetuses.

CONCLUSION

These findings indicate that itraconazole administration at doses of 75, 100, or 150 mg/kg during pregnancy induced maternal and fetal toxicity that could be induced by the genotoxicity and the oxidative damage
Eye movement desensitization and reprocessing (EMDR) therapy in the treatment of depression: a matched pairs study in an inpatient setting
Authors: Hase Michael , Balmaceda Ute Mirian , Hase Adrian , Lehnung Maria , Tumani Visal , Huchzermeier Christian , Hofmann Arne
Published: May 2015

Background

Depression is a severe mental disorder that challenges mental health systems worldwide as the success rates of all established treatments are limited. Eye Movement Desensitization and Reprocessing (EMDR) therapy is a scientifically acknowledged psychotherapeutic treatment for PTSD. Given the recent research indicating that trauma and other adverse life experiences can be the basis of depression, the aim of this study was to determine the effectiveness of EMDR therapy with this disorder.

Method

In this study, we recruited a group of 16 patients with depressive episodes in an inpatient setting. These 16 patients were treated with EMDR therapy by reprocessing of memories related to stressful life events in addition to treatment as usual (TAU). They were compared to a group of 16 controls matched regarding diagnosis, degree of depression, sex, age and time of admission to hospital, which were receiving TAU only.

Results

Sixty‐eight percent of the patients in the EMDR group showed full remission at end of treatment. The EMDR group showed a greater reduction in depressive symptoms as measured by the SCL‐90‐R depression subscale. This difference was significant even when adjusted for duration of treatment. In a follow‐up period of more than 1 year the EMDR group reported less problems related to depression and less relapses than the control group.

Conclusions

EMDR therapy shows promise as an effective treatment for depressive disorders. Larger controlled studies are necessary to replicate our findings.
Prediction of viral filtration performance of monoclonal antibodies based on biophysical properties of feed
Authors: Rayfield William J. , Roush David J. , Chmielowski Rebecca A. , Tugcu Nihal , Barakat Shehab , Cheung Jason K.
Published: April 2015

Controlling viral contamination is an important issue in the process development of monoclonal antibodies (MAbs) produced from mammalian cell lines. Virus filtration (VF) has been demonstrated to be a robust and effective clearance step which can provide ≥4 logs of reduction via size exclusion. The minimization of VF area by increasing flux and filter loading is critical to achieving cost targets as VFs are single use and often represent up to 10% of total purification costs. The research presented in this publication describes a development strategy focused on biophysical attributes of product streams that are directly applicable to VF process performance. This article summarizes a case study where biophysical tools (high‐pressure size exclusion chromatography, dynamic light scattering, and absolute size exclusion chromatography) were applied to a specific MAb program to illustrate how changes in feed composition (pH, sodium chloride concentration, and buffer salt type) can change biophysical properties which correlate with VF performance. The approach was subsequently refined and expanded over the course of development of three MAbs where performance metrics (i.e., loading and flux) were evaluated for two specific virus filters (Viresolve Pro and Planova 20N) during both unspiked control runs and virus clearance experiments. The analyses of feed attributes can be applied to a decision tree to guide the recommendation of a VF filter and operating conditions for use in future MAb program development. The understanding of the biophysical properties of the feed can be correlated to virus filter performance to significantly reduce the mass of product, time, and costs associated with virus filter step development. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:765–774, 2015
Evolution of mitral valve procedural volumes in the advent of endovascular treatment options: Experience at an early‐adopting center in Germany
Authors: Conradi Lenard , Lubos Edith , Treede Hendrik , Pietzsch Jan Benjamin , Weber Simon , Pietzsch Malte , Overlack Karin , Diemert Patrick , Blankenberg Stefan , Reichenspurner Hermann
Published: April 2015

Objectives

Our objectives were to assess the evolution of surgical and endovascular mitral valve procedural volumes and to study utilization and reimbursement effects of transcatheter mitral valve repair (TMVR) at our center and to put these in perspective with the corresponding data at the national level.

Background

TMVR using the MitraClip system has been available in Germany since 2008 as a complementary treatment option for high‐risk or inoperable patients.

Methods

Relevant procedure codes were identified for 2006–2012 and yearly utilization volumes obtained from our center's databases and from the national statistics office. Volumes were analyzed in total, and stratified by treatment approach. Procedure reimbursement at our center was determined for years 2007–2012.

Results

At our center, 378 MitraClip procedures were performed from 2008 to 2012. During this period, surgical volumes grew at an average of 10.6% annually (2008: 262; 2012: 392; 49.6% total growth rate). Total surgical and TMVR reimbursement increased from EUR 3.8 million (2007) to EUR 7.9 million (2012). By comparison, mitral valve procedural volumes grew by 56.1% from 2006 to 2012 at the national level, with TMVR constituting 9.1% of 20,328 procedures in 2012. Since the introduction of MitraClip, nationwide surgical procedural volumes grew at an average of 6.3% annually (2008: 14,477; 2012: 18,478; 27.6% total growth rate).

Conclusions

Growth in procedural volumes during 2006–2012 reflects an increasing supply and subsequent demand for mitral valve procedures. The introduction of TMVR has contributed to overall growth, and has not reduced continued growth in surgical volumes. Our center‐specific analysis suggests a “halo effect” of an integrated approach to mitral valve disease contributing to additional growth in surgical and overall reimbursement volumes. © 2015 Wiley Periodicals, Inc.
Substituent Effects on the Photochromic Properties of Benzothiophene‐Based Derivatives
Authors: Galangau Olivier , Nakashima Takuyama , Maurel François , Kawai Tsuyoshi
Published: April 2015

Five diarylethene photochromic derivatives, the structures of which incorporate a central benzothiophene unit, a left‐hand thiazole group, and a right‐hand benzothiophene group, have been prepared. The compound with a thiazole unit with no substituent on the reaction‐center carbon atom reveals an unprecedented transformation upon light irradiation. When the 4‐position of thiazole is protected by a methyl group, the compounds show high photosensitivity and photochromic properties. In this case, light irradiation affords new compounds with [5]helicene structures featuring the highest redshifted absorption maxima reported to date.
Is mastectomy undertreatment for low‐risk breast cancers eligible for breast‐conserving therapy?
Authors: Bagaria Sanjay P. , Wasif Nabil , Rawal Bhupendra , McLaughlin Sarah A. , Giuliano Armando E.
Published: April 2015

BACKGROUND

Biomarkers are routinely used to predict responses to systemic therapies, but their utility for predicting responses to local therapy for breast cancer is not known. This study determined whether biomarkers could predict responses to breast‐conserving therapy (BCT) and mastectomy.

METHODS

A review of the Surveillance, Epidemiology, and End Results database identified women diagnosed with early‐stage invasive ductal breast cancer and treated with BCT or mastectomy from 1998 to 2008. The estrogen receptor (ER) status and the histologic grade were used to construct 3 biomarker profiles: low risk (ER‐positive, low/intermediate grade), intermediate risk (ER‐positive, high grade), and high risk (ER‐negative, any grade). The primary measured outcome was disease‐specific survival (DSS).

RESULTS

BCT and mastectomy were performed in 114,486 patients (59.2%) and 79,035 patients (40.8%), respectively. There were 122,420 low‐risk patients (63.3%), 34,341 intermediate‐risk patients (17.7%), and 36,760 high‐risk patients (19.0%). Multivariate analyses were performed separately for patients with low‐, intermediate‐, and high‐risk tumors. The adjusted hazard ratios for DSS for patients who underwent mastectomy versus BCT for low‐, intermediate‐, and high‐risk tumors were 1.66 (95% confidence interval [CI], 1.54‐1.79; P < .001), 1.40 (95% CI, 1.29‐1.53; P < .001), and 1.27 (95% CI, 1.19‐1.35; P < .001), respectively.

CONCLUSIONS

Patients with ER‐positive, low‐grade breast cancers who underwent mastectomy had a 66% increase in disease‐specific mortality versus those who underwent BCT. Biomarker profiles defined by the ER status and grade may improve the selection of local therapy for breast cancer. Cancer 2015;121:2705‐2712. © 2015 American Cancer Society
Selective Formation of Indene through the Reaction of Benzyl Radicals with Acetylene
Authors: Parker Dorian S. N. , Kaiser Ralf. I. , Kostko Oleg , Ahmed Musahid
Published: April 2015

The combustion of fossil fuels forms polycyclic aromatic hydrocarbons (PAHs) composed of five‐ and six‐ membered aromatic rings, such as indene (C9H8), which are carcinogenic, mutagenic, and deleterious to the environment. Indene, the simplest PAH with single five‐ and six‐membered rings, has been predicted theoretically to be formed through the reaction of benzyl radicals with acetylene. Benzyl radicals are found in significant concentrations in combustion flames, owing to their highly stable aromatic and resonantly stabilized free‐radical character. We provide compelling experimental evidence that indene is synthesized through the reaction of the benzyl radical (C7H7) with acetylene (C2H2) under combustion‐like conditions at 600 K. The mechanism involves an initial addition step followed by cyclization and aromatization through atomic hydrogen loss. This reaction was found to form the indene isomer exclusively, which, in conjunction with the high concentrations of benzyl and acetylene in combustion environments, indicates that this pathway is the predominant route to synthesize the prototypical five‐ and six‐membered PAH.
Melanin‐Inspired Organic Electronics: Electroluminescence in Asymmetric Triazatruxenes
Authors: Manini Paola , Criscuolo Valeria , Ricciotti Laura , Pezzella Alessandro , Barra Mario , Cassinese Antonio , Crescenzi Orlando , Maglione Maria Grazia , Tassini Paolo , Minarini Carla , Barone Vincenzo , d'Ischia Marco
Published: May 2015

Invited for this month’s cover is the group of Dr. Paola Manini from the University of Naples Federico II. The cover picture shows the concept underlying the design of a melanin‐inspired electroluminescent material for OLED devices. This article is part of a well‐structured research project aimed at imitating Nature’s most enigmatic and fascinating functional pigments for the design and synthesis of innovative biomaterials for organic electronics applications. Read the full text of the article at 10.1002/cplu.201402444.
Highly Efficient Oxygen‐Storage Material with Intrinsic Coke Resistance for Chemical Looping Combustion‐Based CO2 Capture
Authors: Imtiaz Qasim , Kurlov Alexey , Rupp Jennifer Lilia Marguerite , Müller Christoph Rüdiger
Published: April 2015

Chemical looping combustion (CLC) and chemical looping with oxygen uncoupling (CLOU) are emerging thermochemical CO2 capture cycles that allow the capture of CO2 with a small energy penalty. Here, the development of suitable oxygen carrier materials is a key aspect to transfer these promising concepts to practical installations. CuO is an attractive material for CLC and CLOU because of its high oxygen‐storage capacity (20 wt %), fast reaction kinetics, and high equilibrium partial pressure of oxygen at typical operating temperatures (850–1000 °C). However, despite its promising characteristics, its low Tammann temperature requires the development of new strategies to phase‐stabilize CuO‐based oxygen carriers. In this work, we report a strategy based on stabilization by co‐precipitated ceria (CeO2−x), which allowed us to increase the oxygen capacity, coke resistance, and redox stability of CuO‐based oxygen carriers substantially. The performance of the new oxygen carriers was evaluated in detail and compared to the current state‐of‐the‐art materials, that is, Al2O3‐stabilized CuO with similar CuO loadings. We also demonstrate that the higher intrinsic oxygen uptake, release, and mobility in CeO2−x‐stabilized CuO leads to a three times higher carbon deposition resistance compared to that of Al2O3‐stabilized CuO. Moreover, we report a high cyclic stability without phase intermixing for CeO2−x‐supported CuO. This was accompanied by a lower reduction temperature compared to state‐of‐the‐art Al2O3‐supported CuO. As a result of its high resistance towards carbon deposition and fast oxygen uncoupling kinetics, CeO2−x‐stabilized CuO is identified as a very promising material for CLC‐ and CLOU‐based CO2 capture architectures.
Soft‐fault diagnostic method based on locus circle of steady‐state node‐voltage vector
Authors: Li Zhihua , Li Liuchang
Published: April 2015

This study describes a relationship between an element parameter and a fault feature steady‐state node‐voltage vector (SSNVV). The locus of the SSNVV endpoints is proposed and proven to be an arc of circle under certain conditions, whereas the element parameter varies from small to large within a certain range. The arc of circle is called locus circle of SSNVV (LCoSSNVV). An LCoSSNVV‐based soft‐fault diagnostic method is also proposed. The method utilizes three discrete SSNVV endpoints to draw an LCoSSNVV for each element and collects all LCoSSNVVs to produce an LCoSSNVV set for fault diagnosis. In the following diagnostic process, the method measures a fault feature SSNVV of actual faulty circuit and judges which element is faulty on the basis of the relationship between the measured fault feature SSNVV and the LCoSSNVVs in an LCoSSNVV set. Subsequently, the fault can be further subdivided into different types of soft faults on the basis of the relative position of the SSNVV on the LCoSSNVV. A range of the faulty element parameter value can be estimated. Several examples illustrate the method. A measurement solution of SSNVV and a solution of a programming strategy are described. The new LCoSSNVV‐based method would effectively improve the soft‐fault diagnosis process of a linear time‐invariant circuit network. Copyright © 2015 John Wiley & Sons, Ltd.
Towards New Disaster Governance: Subsidiarity as a Critical Tool
Authors: Melo Zurita Maria de Lourdes , Cook Brian , Harms Louise , March Alan
Published: May 2015

Major natural disasters are events where day‐to‐day governance activities are disrupted and a large range of different actors – governmental and non‐governmental – are required to (re)act. Given the inherently chaotic nature of disaster events, and the diverse groups responding to their attendant impacts, clarity about how authority and responsibility are allocated across key disaster management actors is essential. This raises numerous pertinent questions: Are there areas of shared competence between different disaster management actors? Is there a need for them to act in common? Is credible cooperation feasible? Can responsibilities be allocated in a clear and effective manner? In this paper, drawing upon the subsidiarity principle, we provide a review of the academic literature using the role of different actors in disaster management in Australia as the case. The objective of the paper is to synthesise what is known and to, thereby, provoke greater conversation and research of responsibilities during disaster events in Australia and beyond. The ultimate contribution is to help understand how the roles of different disaster management actors can be better reconciled to ensure more effective and efficient outcomes. Copyright © 2015 John Wiley & Sons, Ltd and ERP Environment
Bioremediation of contaminated water with unnatural dye using blue‐green alga spirulina platensis
Authors: Deniz Fatih , Kepekci Remziye Aysun
Published: April 2015

Blue‐green alga Spirulina platensis as a cheap biosorbent was tested for its ability to remove a common azo dye, C.I. Basic Red 46 (C.I. BR 46), from contaminated water. Dye biosorption was a quick process and biosorption reaction reached equilibrium within 60 min. The pseudo‐first‐order, pseudo‐second‐order, logistic, and intraparticle diffusion models were used for the kinetic evaluation. The logistic model presented the best fit to the experimental data. The biosorption data were analyzed using Freundlich, Langmuir, and Dubinin‐Radushkevich isotherm models. Langmuir model fitted better to the equilibrium data than Freundlich model. The maximum dye biosorption capacity was obtained as 25.46 mg g−1 for the biosorbent. Dubinin‐Radushkevich model showed that the predominant mechanism of the dye biosorption was likely physical biosorption. This study suggests promising biosorption potential of S. platensis for C.I. BR 46 removal from contaminated effluents. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 1414–1419, 2015
Chaim Weizmann as a Scientist – From Berlin to the End of His Manchester Period
Authors: Rappoport Zvi
Published: April 2015

After finishing high school in Pinsk, Russia, Chaim Weizmann studied two semesters in the Technical University of Darmstadt, returned home for a year, and in 1895 registered as a chemistry student at the Charlottenburg Technical University at Berlin. He studied and worked in the research group of A. Bistrzycki on synthetic dyestuffs and received a patent in the field. He graduated after 3 years and followed Bistrzycki to Freiburg, Switzerland, where he received in January 1899 a Ph.D. degree with a grade of Magna cum laude. He became a Privatdocent at the University of Geneva, worked in Prof. C. Graebe’s group, published papers and patents and sold patents. In 1904, he moved to the University of Manchester in the UK and collaborated with Prof. William Henry Perkin Jr. in research on synthetic dyestuffs and natural products, and started to work with him on the synthesis of acetone by fermentation. He failed to be nominated to Perkin’s chair when Perkin left in 1913, but became a Reader and head of the biochemistry laboratory. After a conflict with Perkin, he continued alone with the acetone synthesis project, found a bacterium that fermented the starch of corn, potatoes, and chestnuts to acetone and butyl alcohol, which was more efficient than a bacterium found by Perkin and co‐workers. The urgent need for acetone in World War One for military purpose and the high yield of his bacterium in acetone‐producing fermentation, compared with the bacterium of his competitors, made Weizmann’s process the favored one by the British military during the war. Weizmann scaled up acetone production and increased its yield by increasing the sophistication of the process by using a high degree of sterilization. For his contributions he is regarded as the father of industrial biotechnology. His contribution to the war effort opened the door to the British leadership in his Zionistic activity. However, this activity and his scientific activity at later periods are not covered in this article.
Borrowing Constraints and Credit Demand in a Developing Economy
Authors: Ruiz‐Tagle Jaime , Vella Francis
Published: May 2015

This paper investigates the determinants of credit demand in the presence of borrowing constraints in a developing economy. We model the determinants of observed debt for Chilean households while accounting for selection bias and the endogeneity of their income and specific household assets. Using a novel Chilean dataset, we estimate the relationship between household characteristics and consumer and mortgage debt. We find substantial differences in the nature of these relationships across the types of debt. For example, we find that the income elasticity for consumer debt is greater than 1 whereas for mortgage debt it is not. The results suggest the increased availability of credit, combined with the aging of the Chilean population, is likely to drastically change the distribution and level of Chilean debt. These findings are particularly relevant for other developing economies currently experiencing rapid income and debt growth. Copyright © 2015 John Wiley & Sons, Ltd.
Fabrication of silk fibroin film using centrifugal casting technique for corneal tissue engineering
Authors: Lee Min Chae , Kim Dong‐Kyu , Lee Ok Joo , Kim Jung‐Ho , Ju Hyung Woo , Lee Jung Min , Moon Bo Mi , Park Hyun Jung , Kim Dong Wook , Kim Su Hyeon , Park Chan Hum
Published: May 2015

Films prepared from silk fibroin have shown potential as biomaterials in tissue engineering applications for the eye. Here, we present a novel process for fabrication of silk fibroin films for corneal application. In this work, fabrication of silk fibroin films was simply achieved by centrifugal force. In contrast to the conventional dry casting method, we carried out the new process in a centrifuge with a rotating speed of 4000 rpm, where centrifugal force was imposed on an aluminum tube containing silk fibroin solution. In the present study, we also compared the surface roughness, mechanical properties, transparency, and cell proliferation between centrifugal and dry casting method. In terms of surface morphology, films fabricated by the centrifugal casting have less surface roughness than those by the dry casting. For elasticity and transparency, silk fibroin films obtained from the centrifugal casting had favorable results compared with those prepared by dry casting. Furthermore, primary human corneal keratocytes grew better in films prepared by the centrifugal casting. Therefore, our results suggest that this new fabrication process for silk fibroin films offers important potential benefits for corneal tissue regeneration. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 508–514, 2016.
Arctigenin, a Natural Lignan Compound, Induces Apoptotic Death of Hepatocellular Carcinoma Cells via Suppression of PI3‐K/Akt Signaling
Authors: Jiang Xiaoxin , Zeng Leping , Huang Jufang , Zhou Hui , Liu Yubin
Published: April 2015

In this study, we explored the cytotoxic effects of arctigenin, a natural lignan compound, on human hepatocellular carcinoma (HCC) cells and check the involvement of phosphatidylinositol 3‐kinase (PI3‐K)/Akt signaling. HCC cells were treated with different concentrations of arctigenin and cell viability and apoptosis were assessed. Manipulating Akt signaling was used to determine its role in the action of arctigenin. Arctigenin significantly inhibited the viability of HCC cells in a concentration‐dependent manner. Arctigenin induced apoptosis and activation of caspase‐9 and ‐3. Overexpression of a constitutively active Akt mutant blocked arctigenin‐induced apoptosis. Combinational treatment with arctigenin and the PI3‐K inhibitor LY294002 significantly enhanced apoptosis. Arctigenin reduced the expression of Bcl‐xL, Mcl‐1, and survivin and the phosphorylation of mTOR and S6K, which were significantly reversed by overexpression of constitutively active Akt. This is the first report about the anticancer activity of arctigenin in HCC cells, which is mediated by inactivation of PI3‐K/Akt signaling.
The Camptothecins: A Reborn Family of Antitumor Agents
Authors: Curran Dennis P.
Published: May 2015

A brief overview of the medicinal chemistry of the camptothecin family of antitumor agents is followed by a summary of a new synthetic approach to this class of compounds. This approach features a new 4 + 1 radical annulation.
Synthesis and Cyclization of Sulfur‐Substituted Azido Dienes to Pyrrolizidine and Indolizidine Moieties
Authors: Chou Shang‐Shing P. , Tsao Hung‐Juan , Lee Chien‐Ming , Sun Chung‐Ming
Published: May 2015

Sulfur‐substituted azido dienes 1 and 11, conveniently prepared from the corresponding 3‐sulfolenes 5 and 10, were thermolyzed to give pyrrolizidine and indolizidine products, 6, 7 and 14.
Additional Alkaloids from Phoebe Formosana
Authors: Lee Shoei‐Sheng , Tsai Fang‐Yeh , Chen Ih‐Sheng , Liu Karin C. S.
Published: May 2015

Four additional phenolic bases ‐ laurotetanine (2), asimilobine (3), norjuziphine (4) and juziphine (5) ‐ were isolated during the reinvestigation of the roots of P. formosana by combination of centrifugal partition chromatography and common separation methods. The latter two bases are first isolated from Lauraceous plants. Their structures were elucidated mainly by NMR spectral analysis.
Electrochemical Reduction of Substituted Anthracenes
Authors: Cheng Ellen , Sun Ta‐Chien , Oliver Su Y.
Published: May 2015

A systematic investigation of the electrochemical reduction of substituted anthracenes in N,N‐dimethylformamidc has unveiled the reductive properties of the aromatic compounds. For the anthracenes with a reversible first reduction, the redox potential exhibits linearity vs a value of the Hammett equation. For anthracenes with an irreversible first reduction, the electron transfer and chemical reaction occur via either a sequential or a concerted pathway. When the irreversible first reduction occurs at a potential more negative than E1/2 calculated from the σ value, the reaction occurs via a sequential pathway, such as for 9‐chloroanthracene. When the irreversible first reduction occurs at a potential more positive than the expected E1/2, the reaction occurs via a concerted mechanism of electron transfer and bond breaking, such as for 9‐chloromethylanthracenc. The displacement of the halide results in the parent polyaromatic hydrocarbons, as in dicated by the spectroelectrochemical method.
OPSAES: Organic Pollutants Sampling and Analysis Expert System
Authors: Chen Chi‐Ping , Ling Yong‐Chien
Published: May 2015

Sampling and analyses using standard methods has been the most efficient means to obtain reliable results. Standard method selection has relied heavily on the analyst's heuristic and algorithmic capabilities. An integrated expert‐database system, OPSAES, was developed to stimulate this expertise that would assist the user to select methods to sample and analyze organic pollutants via specification of analytical descriptors. The merits of improvements in environmental analytical data generation process through the use of OPSAES are demonstrated.
Phospholipase A2‐Catalyzed Hydrolysis of 1,2‐DimyristoyI‐sn‐Glycero‐3‐Phosphocholine in Organic Solvents
Authors: Wu Fang‐Chen , Lin Gialih
Published: May 2015

The phospholipase A2‐catalyzed hydrolysis of phosphatidylcholine in organic solvents is described. The effects of various sources of enzymes are discussed; among five phospholipases A2, bee venom enzyme has the greatest activity, Naja naja venom and Naja mocambique enzymes have moderate activities, and pancreatic enzymes have the least activities. The effects of adducts such as alcohols, ether, and bovine serum albumin in chloroform on this catalysis are discussed; adducts, such as ether or alcohol, in small proportions increased the hydrolysis rate, but in large proportions inhibited hydrolysis. Bovine serum albumin increased slightly the phospholipase A2 catalysis rate. From the effect of temperature on this catalysis in chloroform, the substrate conformation at the α‐memylcne region of acyl chains is a major factor for activation of phospholipases A2, confirming our previous conclusion that the substrate conformation is an important factor in the activation of phospholipase A2.
Kinetic Methods of Analysis: How Do They Rate?
Authors: Crouch Stanley R.
Published: May 2015

During the past few years there has been a resurgence of interest in kinetic aspects of analytical chemistry and in kinetic methods of analysis. The increased activity is a result of advances that have been made in instrumentation and in data processing techniques. Still, the kinetic approach is not widely applied by practicing analytical chemists. Why is this true? Why are kinetic methods not among the most common methods in use by analytical chemistry? This paper discusses the advantages and limitations of kinetic methods and addresses the probable reasons that they are not widely used. Several new principles have cmerged that are guiding the development of new kinetic‐based determinations. These developments have made it possible to compensate for errors that result from changes in reaction conditions and to determine accurately multiple components in mixtures. With these advances kinetic methods are approaching the reliability of traditional equilibrium‐based determinations and should be re‐evaluated by analytical chemists.
Applications of Macrocyclic Polyethers in Analytical Sensors and Ion Separation
Authors: Shih Jeng‐Shong
Published: May 2015

Artificial macrocyclic polyethers were synthesized and applied as neutral carriers for ion‐selective PVC membrane electrodes, ion‐chromatographic packing materials, extractants and adsorbents for ion separation, coating materials for piezoeletrical membrane sensors for organic species, and ion‐transport carriers through liquid membranes. Ion‐selective electrodes such as those for K+ Na+, UO22+, Cs+, Pb2+, Fe3+, Hg2+ and Ag+ ions based on crown ether‐phosphotungstic acid (PW) precipitates and dithio crown ethers respectively were prepared and showed good sensitivity and selectivity. Crown ether‐PW precipitates were applied as adsorbents of rare‐earth ions and some common heavy‐metal ions. Some rare‐earth ions were easily extracted with crown ethers, especially 15‐crown‐5. Poly(stytene/divinyl benzene) cryptand‐22 resin was synthesized and applied as a bifunctional stationary phase of ion chromatography to separate bom cations and anions, even some organic carboxylate geometric isomers. Crown ethers such as mono‐benzo‐15‐crown‐5 was successfully applied as a coating material on piezoelectric quartz membrane sensors for some organic species. The oscillation frequency of the crown‐ether quartz‐membrane sensor was sensitive to organic vapours such as amines and alcohols. Upon adsorption of organic species on the crown‐ether quartz membrane, the oscillation frequency of the sensor decreased obviously. Special crown ether such as dibenzo‐16‐crown‐5‐oxyacetic acid, decyl‐cryptand‐22 and 1, 4‐dihydro‐pyridine‐18‐crown‐5 were synthesized and successfully applied as ion‐transport carriers (ionophores) for transport of Na+ K+ and Mg2+ ions through liquid membranes.
Comparison of Triple Quadrupole and Double Focusing Mass Spectrometers to Investigate Collision‐Induced Dissociation and Metastable Ions of Glycoconjugates
Authors: Ju Dar‐Der , Li Ding‐Tzai , Wei Guor‐Jien , Her Guor‐Rong
Published: May 2015

Glycoconjugates, such as chromophore‐labeled disaccharides and permethylated glycosphingolipids (GSL) were used for comparison of triple quadrupole and double focusing mass spectrometers in analysis of product ions. A profound effect of collision energy was observed in the product ion spectra of ceramide ions (fragment ions of permethylated GSL): more product ions were observed from a double focusing mass spectrometer. Besides collision energy, the structure of the analyte had a significant effect on the formation of product ions. Despite the fact that masses of protonated molecular ions (MH+) of permethylated GSL are significantly larger than their ceramide fragments, the low‐energy and high‐energy product ion spectra of MH+ are, in general, similar. In a double focusing mass spectrometer of reversed geometry, more metastable ions were observed in the first field free region (FFR) than in the second FFR. The metastable ions observed in the second FFR were similar to those observed in low‐energy collision‐induced dissociation (CID). Although a double focusing mass spectrometer is superior to triple quadrupole instrument for detection of product ions, the poor resolution in either the selection of precursor ion or in the product ion spectra can be a serious problem in analysis of a mixture with similar masses.
Lipid and Protein Thermotropic Transition of Porcine Stratum Corneum by Microscopic Calorimetry and Infrared Spectroscopy
Authors: Lin Shan‐Yang , Liang Run‐Chu , Lin Tsung‐Chien
Published: May 2015

Microscopic differential scanning calorimetry and Fourier transform infrared spectrometry (DSC‐FTIR) were combined to investigate the thermal response and IR spectra of lipid and protein in the process of a phase transition in porcine stratum corneum (SC) by KBr disc method. The alterations of bands associated with the CH2 stretching vibrations near 2850 and 2920 cnv−1 were used to determine the phase transformation of lipid with temperature. The peaks of amide I and II of protein were used to investigate the thermal conversion of protein. A reheating process was performed. The results indicate that the bands of lipid near 2900 cm−1 shifted to greater wavenumber with increased temperature, but reversibly. The band due to deformation mode of the lipid altered from shoulder to smooth with increased temperature. During heating, α‐keratin of the protein transformed gradually to p‐keratin, but irreversibly. Thermal transitions that occurred near 78 °C and 115 °C for the sample on first heating were associated with phase transition of the lipid‐protein complex and the protein in porcine SC, respectively. After reheating, this phase transitional temperature of the lipid‐protein complex in porcine SC decreased from 78 to 68 °C, and the transition of protein near 115 °C almost disappeared. This behaviour indicates that porcine SC after heating might alter its structure. The thermally altered proportion of lipid was 43.98% and the thermally induced proportion of protein was 41.48% during the first heating process, but the restoration of lipid during the cycle of heating, cooling and reheating was 37.64%. The variation is attributed to the denaturation of protein to alter the structure of lipid‐protein complex after first heating. This technique was simple, precise and reproducible for simple determination of stratum corneum or biological samples in a brief period.
A Multifractal Approach to Heterogeneous Reactions over Fractal Surfaces
Authors: Lee Chung‐Kung , Liang Wen‐Hau , Lee Shyi‐Long
Published: May 2015

Monte‐carlo simulations of modified Eley‐Rideal mechanisms (ER) possessing decay and enhanced sticking probability and a three‐step catalytic reaction (TCR) over fractal surfaces were performed to examine the morphological effect on these surface reactions. Effects of decay and enhancing profiles on the reaction probability distribution (RPD) for the ER reaction and effects of varying probability of reaction steps and cluster sizes on the normalized selectivity distribution (NSD) for TCR were men analyzed with multifractal scaling techniques. For the ER mechanism, RPD tends to be uniform for rapid decay and relatively concentrated at greater enhancing rate. For TCR, increased cluster size is found to decrease the position sensitivity of NSD. A large ratio of dimerization to isomerization increases the position distinction among active sites when the adsorption probability equals to unity. At small p1, i.e., adsorption probability « 1, the ratio of dimerization to isomerization causes no effect on the NSD.
Preparation and Characterization of Chemically Bound Tartrate‐Sillca Gel as Sorbent for Ligand Exchange Chromatography
Authors: Chyueh Sun‐Dsong , Liu Chuen‐Ying
Published: May 2015

Tartrate‐based sorbents of two kinds for ligand‐exchange chromatography were prepared by covalent bonding of functional groups to silica gel through an amide bond. The structure and conversion of functional groups of the resin were confirmed with IR spectral and elemental analysis. The influence of pH on adsorption of metal ions to the resin was examined. The coordination behaviour of the sorbent was investigated by means of IR, EPR and electronic absorption spectroscopy. The results indicate that the affinity of metal ions toward the synthesized resins decreased in the order Cu(II) > Zn(II) > Cd(II). The conformation of the copper(II)‐sorbent complexes may be distorted tetragonal, whereas those of zinc(II) and cadmium(II) may be tetrahedral. These complexes between metal ion and sorbent were investigated as a stationary phase for enantiomeric separation of underivatized amino acids. Factors affecting the retention and the sample selectivity were examined. The interactions between sorbent metal complexes and analytes in this ternary system were also investigated.
A Novel Reaction of Ruthenium Carbonyl and Tetrafluorodisila‐3,5‐cyclohexadlene
Authors: Cheng W. S. , Huang C. Y. , Liu C. S. , Lec C. Y.
Published: May 2015

In hexane solution, the decomposition of (1,1,6,6‐tetrafluoro‐3,4‐di‐t‐butyl‐1, 6‐disila‐2,4‐hexadiene)ruthenium (II) tetracarbonyl 2, led to formation of compound (η4‐1,1‐difluoro‐3,4‐di‐t‐butyl‐sila‐2,4‐cyclopentadiene)ruthenium(O)tricarbonyl 3 and monomeric SiF2 that added to cyclic diene compound 1,1,2,2‐tetrafluoro‐4,5‐di‐t‐butyl‐disila‐3, 5‐cyclohexadiene 1, to form bicyclic compound 4. SiF2 was for the first time generated at such a low temperature and trapped with a conjugated diene.
Crystal Structure Refinement of Gaivinoxyl Radical, C29H41O2, Based on Synchrotron X‐ray Powder Diffraction and Rietveld Method
Authors: Sbeu Hwo‐Shuenn , Lee Chih‐Hao , Wang Yu , Chiang Long Y.
Published: May 2015

High‐resolution X‐ray powder diffraction with synchrotron radiation coupled with Rietveld analysis has been used recently as one of the best way to obtain structural information from a powder specimen. Molecular and crystal structures of Che gaivinoxyl radical (C29H41O2) were studied by means of powder diffraction using NSLS (National Synchrotron Light Source) with λ = 1.5855 A and a rotating anode with Cu Kα radiation. The space group of the crystal is C 2/c with refined lattice parameters a = 23.786(1), b = 10.8611(4), c= 10.6766(4) Å, β = 106.634(3)° Z = 4. The peak shape was fitted with a pseudo‐Voigt profile function. The preferred orientation is along the >011< direction of the needle‐like crystals. Final refinements were converged to give agreement indices Rp 0.08 and 0.17 respectively for synchrotron radiation and rotating anode data. The fitting of the peak profile and refined parameters from the synchrotron radiation data are significantly better than those from rotating anode data. No significant differences are found between single crystal results and those in this work. This work provides evidence that powder diffraction, especially with synchrotron radiation, could be used as one means of structural analysis even for such a weakly scattering organic material.
Formation of Pyrrole Derivatives from Heteroatom‐Substituted Acetonitriles
Authors: Jeng Huey‐Jiuan , Fang Jim‐Min
Published: May 2015

Aminomalononilrile reacted with conjugated carbonyl compounds to give 3H‐pyrrolines. Treatment of 2‐cbloro‐2‐phenyllhioacetonitrile with alkenes in the presence of potassium t‐butoxide afforded 1‐pnenylthiocyclopropanecarbonitriles, which reacted with nucleophiles in 1,2‐, 1,4‐ or 1,6‐addition modes. The 1,2‐adducts (cyclopropylimines) rearranged in situ to give substituted pyrroles.