bluuebunny/crossref_metadata_2025 huggingface dataset:
Postmenopausal estradiol–progestagen therapy and risk for uterine cervical cancer
Authors: Jaakkola Susanna , Pukkala Eero , K.Lyytinen Heli , Ylikorkala Olavi
Published: October 2011

The aim of this study was to evaluate the association of postmenopausal estradiol–progestagen therapy (EPT) with the risk for precancerous lesions, squamous cell carcinoma and adenocarcinoma of the uterine cervix. All Finnish women who had used EPT in 1994–2008 for at least 6 months (n = 243,857) at the age of 50 years or more were identified from the national Medical Reimbursement Registry and linked to the Finnish Cancer Registry. The incidence of cervical precancerous or cancerous lesions among EPT users was compared to that in the background population. There were 210 EPT users with squamous lesions (178 with precancerous and 32 with cancer) and 79 EPT users with glandular lesions (14 precancerous and 65 adenocarcinomas). The ever use of EPT did not associate with the incidence of precancerous lesions, but the risk for squamous cell carcinoma decreased (standardized incidence ratio 0.41; 95% confidence interval 0.28–0.58) and that for adenocarcinoma increased (1.31; 1.01–1.67). After the use of EPT for 5 years, the risk for squamous cell carcinoma decreased (0.34; 0.16–0.65), and the risk for adenocarcinomas increased (1.83; 1.24–2.59). The prolonged use of EPT is associated with the occurrence of cervical malignancies. If the association would be a causal one, the use for 5+ years among 10,000 women followed for 10 years would mean about two to three fewer cases of cervical squamous cell carcinoma but about two extra cases with adenocarcinoma.
What It Is They Do: Differentiating Knowledge and Literacy Practices Across Content Disciplines
Authors: Johnson Holly , Watson Patricia A. , Delahunty Tina , McSwiggen Patrick , Smith Tara
Published: October 2011

This study addresses the gap that exists between literacy educators’ knowledge of content disciplines and the literacy strategies often suggested for use in content classrooms. The authors worked with disciplinary experts in mathematics and geography to understand the differences that exist in their conceptions of the disciplines and what it means to be literate in them. Study results were categorized into themes, which include “major understandings of the field,” “literacy in the discipline,” and “practice of the discipline.” Further subcategories include texts used in the discipline; the types of strategies used to become literate in the discipline, and the types of questions addressed within the discipline. Implications for teachers and teacher candidates are also addressed.
The effect of ascorbic acid on the distribution of soluble Cr and Co ions in the blood and organs of rats
Authors: Afolaranmi Grace A. , Helen Grant M.
Published: October 2011

Metal ions (Cr and Co) are released from metal orthopaedic implants in situ. We investigated tissue dissemination of Cr III, Cr VI and Co II ions in the body, and determined if administration of ascorbic acid (AA) affected their in vivo distribution using rats as a model system. Organs of rats treated with both Cr (VI) and Co (II) have higher metal ion levels when compared with control levels in the organs of rats without metal treatment. The reduced form of chromium, Cr III, is reported to be relatively impermeant to cell membranes in vitro, and in line with this, Cr III did not distribute into the organs of the rats after administration in vivo. Potent in vitro reduction of Cr (VI) to Cr III by AA was observed in this study. Prior intraperitoneal injection of AA lowered tissue uptake of both Cr VI and Co II, and increased faecal excretion, but not to a significant extent. AA may only be effective in increasing elimination of Cr VI at high concentrations when plasma reduction is saturated, and may be of limited therapeutic use in patients with orthopaedic implants. Copyright © 2011 John Wiley & Sons, Ltd.
Prevalence of congenital cytomegalovirus infection in Slovenia: A study on 2,841 newborns
Authors: Paradiž Katarina Rednak , Seme Katja , Puklavec Evelin , Paro‐Panjan Darja , Poljak Mario
Published: October 2011

Human cytomegalovirus (CMV) is the most frequent cause of congenital infection in humans. In the first prevalence study of congenital CMV infection in Eastern and Central Europe, all neonates born in a 22‐month period in two Slovenian maternity units (total of 2,841 newborns) were screened prospectively for congenital CMV infection by a real‐time polymerase chain reaction (PCR) in urine. In all newborns with positive screening results, plasma and dried blood spots (DBS) collected at birth were tested additionally for CMV DNA. Congenital CMV infection was confirmed by virus isolation from a urine sample collected within the first 2 weeks of life. Congenital CMV infection was identified in four out of 2,841 newborns tested (incidence 0.14%; 95% CI, 0.05–0.39%). In four newborns with confirmed congenital infection, the concentration of CMV DNA in urine ranged from 4.68 to 8.18 log10 copies/ml, all four newborns had detectable CMV DNA in plasma taken at birth (1.26–3.34 log10 copies/ml) and two out of four had detectable CMV DNA in DBS collected during newborn metabolic screening. None of the four newborns with confirmed congenital CMV infection was symptomatic. The study showed that the prevalence of congenital CMV infection at birth in Slovenia is among the lowest in the world and that CMV DNA PCR testing of urine is a suitable and affordable real‐time screening strategy for congenital CMV infection. If it is performed in 24 mini‐pools, the cost of screening is 1.4 €/newborn and the cost of detecting a single newborn with congenital CMV infection 1,000 €. J. Med. Virol. 84:109–115, 2011. © 2011 Wiley Periodicals, Inc.
Conductive Polymer for Elevated Temperature Applications Based on Sodium Sulfosuccinate Coupled Poly(ethylene glycol)s
Authors: Zimmerer Cordelia , Nagel Jürgen , Steiner Gerald , Heinrich Gert
Published: October 2011

Sodium sulfosuccinate coupled poly(ethylene glycol) (PEG) (S–PEG–SS) conductive polymers for hot melt adhesives are synthesized from PEG, maleic anhydride, and sodium hydrogen sulphite using a one‐pot three‐step reaction. Infrared spectroscopy and 1H NMR spectroscopy are used to characterize the molecular structure and to determine the yield of esterification. S–PEG150–SS has the highest yield of esterification, whereas S–PEG2000–SS provides the lowest yield of esterification. Gel permeation chromatography and shear viscosity measurements are applied to characterize multiple condensation products and to describe the viscoelastic properties. The results reveal that the viscoelastic properties and the conductivity depend on molar mass of esterified PEG, on the degree of condensation, and on the concentration of ions.
α2‐Agonisten in Anästhesie und Intensivmedizin
Authors: Tonner Peter H. , Paris Andrea
Published: October 2011

α2‐Agonisten spielen heute eine wichtige Rolle in der Anästhesie und Intensivmedizin. Bei sachgemäßem Einsatz sind die Nebenwirkungen substanzspezifisch und vorhersehbar. Die Kombination aus sedierenden und analgetischen Eigenschaften bei gleichzeitig fehlender Atemdepression und Glättung des hämodynamischen Profils durch sympatholytische Eigenschaften machen dies Substanzklasse heute zu einer wichtigen Bereicherung des pharmakologischen Armamentariums in der Anästhesie und Intensivmedizin.
Quality Assessment of Commercial Magnoliae Officinalis Cortex by 1H‐NMR‐based Metabolomics and HPLC Methods
Authors: Jiang Yong , Vaysse Julie , Gilard Véronique , Balayssac Stéphane , Déjean Sébastien , Malet‐Martino Myriam , David Bruno , Fiorini Christel , Barbin Yves
Published: October 2011

Introduction

The quality control of Magnoliae officinalis Cortex, a commonly used traditional Chinese medicine, is currently based on the assay of the two active compounds, honokiol and magnolol, by TLC or HPLC.

Objective

To compare 1H‐NMR‐based metabolomics with the HPLC method for controlling the quality of Magnoliae officinalis Cortex. To identify the metabolites contributing to the differences between the samples and to discriminate different medicinal parts and geographic origins of these samples by 1H‐NMR‐based metabolomics.

Methodology

1H‐NMR and several multivariate analysis techniques were applied to analyse the extracts of 18 batches of Magnoliae officinalis Cortex commercial samples, and the contents of honokiol and magnolol in these samples were determined by HPLC. The correlation analysis between the data from 1H‐NMR and HPLC was performed with the mixOmics software based on an unsupervised method.

Results

Honokiol and magnolol were the main compounds responsible for the discrimination of samples from different batches, thus proving that the choice of these two compounds as markers for quality assessment by HPLC is relevant. The two sources of Magnoliae officinalis Cortex recorded in the Chinese Pharmacopoeia, Magnolia officinalis and Magnolia officinalis var. biloba, could be differentiated from 1H‐NMR data, but the pattern recognition analysis by PLS‐DA was unsuccessful in discriminating samples from various geographical origins.

Conclusion

The combination of 1H‐NMR that gives a comprehensive profile of the metabolites and HPLC that targets two biomarkers is an efficient means for a better quality control of Magnoliae officinalis Cortex. Copyright © 2011 John Wiley & Sons, Ltd.
Tautomerism, dynamic properties and level crossing in 2‐(pyridin‐2‐yl) furan‐3‐ol by density functional theory and natural bond orbital analysis
Authors: Tavakol Hossein
Published: October 2011

2‐(Pyridin‐2‐yl)furan‐3‐ol (PYFO, T1) and (2E)‐2‐(pyridin‐2(1H)‐ylidene)furan‐3(2H)‐one (PYFO, T2) were considered to study their tautomerism interconversions, relative rotations of rings, OH bond rotations, and possibility of crossing between those energy surfaces using density functional theory methods at the Becke, three‐parameter, Lee–Yang–Parr/6‐311++G** level of theory. The optimized structures of both tautomers and the transition state of tautomerism are completely planar. A study of tautomerism in PYFO shows that T1 tautomer is about 24.38 kJ/mol more stable than T2. The rate constants of tautomerism interconversion for converting T1 to T2 is 1.98 × 108 M–1 s–1 and for converting T2 to T1 is 3.70 × 1012 M–1 s–1 at room temperature that show the possibility of this tautomerism with high rate at ambient temperature. Rotation of OH bond in T1 shows two minimum (at 0° (global minimum) and 180° (local minimum)) and a transition state at 110° (and 265°) with 47.10 kJ/mol barrier energy. Relative rotation of rings shows global minimum at 0° for both tautomers and local minimum at 154° and 206° for T1 and 180° for T2. The barrier energy for ring rotation of T1 was observed at 90° and 270° with 63.69 kJ/mol height and for T2 was observed at 120 with 170.86 kJ/mol height. Interestingly, the energy levels of ring rotations for T1 and T2 are the same and crossing between them was observed. Therefore, although these two potentials do not have the same symmetries, because of the crossing between their energy level, crossing is not avoided. Copyright © 2011 John Wiley & Sons, Ltd.
Inactivation of Bacillus subtilis Spores in Water by a Direct‐Current, Cold Atmospheric‐Pressure Air Plasma Microjet
Authors: Sun Peng , Wu Haiyan , Bai Na , Zhou Haixia , Wang Ruixue , Feng Hongqing , Zhu Weidong , Zhang Jue , Fang Jing
Published: October 2011

Bacillus subtilis spores suspended in distilled water was effectively inactivated in 6 min by a direct‐current atmospheric pressure non‐thermal air plasma microjet. Scanning electron microscopic images show clear distortion and debris of spores after plasma treatment. Direct contribution by temperature and pH change of water as well as relatively long lived species in plasma activated water (PAW) is excluded. Short lived species (such as •OH, •O and O2(1Δg)) are detected in the plasma‐water system by electron spin resonance spectroscopy, and are considered to be the most important agents in the inactivation process.

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Global impact of asthma on children and adolescents' daily lives: The room to breathe survey
Authors: Wildhaber Johannes , Carroll William D. , Brand Paul L.P.
Published: October 2011

Objective

To establish children and adolescents' perspectives regarding their asthma and its impact upon their daily lives.

Design

A 14‐item questionnaire.

Setting

Canada, Greece, Hungary, The Netherlands, the United Kingdom, and South Africa.

Participants

Children/adolescents (aged 8–15 years) with physician‐diagnosed asthma.

Intervention

Interviews were conducted by telephone (Canada, Greece, Hungary, The Netherlands, and the United Kingdom) or face‐to‐face (South Africa).

Outcome Measures

Asthma symptoms, impact on activities, and quality of life.

Results

Of the 943 children/adolescents interviewed, 60% were male. Most (81%) described their asthma as “not too bad” or “I only get it every now and then,” with only 4% reporting their asthma as being “very bad”; however, 92% experienced asthma‐related coughing and 59% reported nocturnal awakening. Over half (57%) of children/adolescents believed they could predict when their asthma would make them ill; the most common initial symptoms being breathlessness (41%) and bad cough (33%). They considered the worst things about having asthma to be the symptoms of an asthma attack (32%) and not being able to play sport (25%). Almost half (47%) of children/adolescents felt that their asthma affected their ability to play sport or engage in physical activity. One in ten reported they had suffered asthma‐related bullying.

Conclusions

Children/adolescents underestimate the severity of their asthma, and overestimate its control, indicating that they expect their illness to be symptomatic. Asthma has a substantial impact on their daily lives, particularly on physical activity and social functioning. Efforts are required to improve asthma control and expectations of health in children/adolescents. Pediatr Pulmonol. 2012; 47:346–357. © 2011 Wiley Periodicals, Inc.
Prenatal cigarette smoke exposure and postnatal respiratory responses to hypoxia and hypercapnia
Authors: Pendlebury Jonathan D. , Yusuf Kamran , Bano Shehr , Lumb Kathleen J. , Schneider Jennifer M. , Hasan Shabih U.
Published: October 2011

Prenatal cigarette smoke (CS) exposure, in combination with hypoxia and/or hyperthermia can lead to gasping and attenuated recovery from hypoxia in 7 days old rat pups. We studied 95 unanesthetized spontaneously breathing 14 days old rat pups to investigate if the destabilizing effects of increased ambient temperature and prenatal CS exposure on respiratory control observed in 7 days old rats were still evident at day 14. This postnatal age was selected as it is beyond the analogous risk period for SIDS in human. Furthermore, we investigated if the breathing responses to hypercapnia are affected by prenatal CS exposure. Since high ambient (HA) temperature can lead to gasping and aberrant respiratory control, we recorded respiratory patterns at low (24–25°C) and high (29–30°C) ambient temperatures, and under hypoxic or hypercapnic states. No gasping was observed in 14 days old rat pups. During hypoxia, breathing frequency increased in the CS‐exposed group under low and HA temperatures. Rectal temperature decreased only in the sham group in response to low ambient temperature hypoxia. At HA temperature, breathing frequency increased in both sham and CS‐exposed groups during hypercapnia, however, it remained elevated during washout period only in the sham group. We demonstrate that prenatal CS exposure continues to have profound effects on respiratory and thermoregulatory responses to hypoxia and hypercapnia at day 14. The attenuated respiratory and thermoregulatory responses to acute hypoxia and hypercapnia on day 14 demonstrate a strong interaction between CS exposure, respiratory control, and thermoregulation during postnatal maturation. Pediatr Pulmonol. 2012; 47:487–497. © 2011 Wiley Periodicals, Inc.
Evaluating Intrusion‐Tolerant Certification Authority Systems
Authors: Lin Jingqiang , Jing Jiwu , Liu Peng
Published: October 2011

Various intrusion‐tolerant certification authority (CA) systems have been proposed to provide attack resilient certificate signing (or update) services. However, it is difficult to compare them against each other directly, due to the diversity in system organizations, threshold signature schemes, protocols and usage scenarios. We present a framework for intrusion‐tolerant CA system evaluation, which consists of three components, namely, an intrusion‐tolerant CA model, a threat model and a metric for comparative evaluation. The evaluation framework covers system organizations, protocols, usage scenarios, the period of certificate validity, the revocation rate and the mean time to recovery. Based on the framework, four representative systems are evaluated and compared in three typical usage scenarios, producing reasonable and insightful results. The interdependence between usage scenarios and system characteristics is investigated, providing a guideline to design better systems for different usage scenarios. The proposed framework provides an effective and practicable method to evaluate intrusion‐tolerant CA systems quantitatively, and helps customers to choose and configure an intrusion‐tolerant CA system. Moreover, the comparison results offer valuable insights to further improve the attack resilience of intrusion‐tolerant CA systems. Copyright © 2011 John Wiley & Sons, Ltd.
Significance of Remyelination by Neural Stem/Progenitor Cells Transplanted into the Injured Spinal Cord
Authors: Yasuda Akimasa , Tsuji Osahiko , Shibata Shinsuke , Nori Satoshi , Takano Morito , Kobayashi Yoshiomi , Takahashi Yuichiro , Fujiyoshi Kanehiro , Hara Chikako Miyauchi , Miyawaki Atsuhi , Okano Hirotaka James , Toyama Yoshiaki , Nakamura Masaya , Okano Hideyuki
Published: October 2011

Previous reports of functional recovery from spinal cord injury (SCI) in rodents and monkeys after the delayed transplantation of neural stem/progenitor cells (NS/PCs) have raised hopes that stem cell therapy could be used to treat SCI in humans. More research is needed, however, to understand the mechanism of functional recovery. Oligodendrocytes derived from grafted NS/PCs remyelinate spared axons in the injured spinal cord. Here, we studied the extent of this remyelination's contribution to functional recovery following contusive SCI in mice. To isolate the effect of remyelination from other possible regenerative benefits of the grafted cells, NS/PCs obtained from myelin-deficient shiverer mutant mice (shi-NS/PCs) were used in this work alongside wild-type NS/PCs (wt-NS/PCs). shi-NS/PCs behaved like wt-NS/PCs in vitro and in vivo, with the exception of their myelinating potential. shi-NS/PC-derived oligodendrocytes did not express myelin basic protein in vitro and formed much thinner myelin sheaths in vivo compared with wt-NS/PC-derived oligodendrocytes. The transplantation of shi-NS/PCs promoted some locomotor and electrophysiological functional recovery but significantly less than that afforded by wt-NS/PCs. These findings establish the biological importance of remyelination by graft-derived cells for functional recovery after the transplantation of NS/PCs into the injured spinal cord. STEM CELLS 2011;29:1983–1994.
Putting the Fun Back Into Fluency Instruction
Authors: Cahill Mary Ann , Gregory Anne E.
Published: October 2011

Based on recent research in fluency instruction, the authors present a scenario in which a teacher focuses her fluency instruction on authentic fluency tasks based in performance. Beginning with establishing a student‐friendly definition of fluency and culminating with student engagement in fun fluency activities, this article explores the possibilities for bringing joy back into repeated reading practice. Directions for creating a fun fluency kit for classroom use are included.
IP3R function in cells of the immune system
Authors: Akimzhanov Askar M. , Boehning Darren
Published: October 2011

Calcium ions regulate almost all cellular processes. Inositol 1,4,5‐trisphosphate receptors (IP3Rs) are ubiquitous calcium channels which mediate calcium release primarily from endoplasmic reticulum stores. IP3Rs are activated by the soluble second messenger inositol 1,4,5‐trisphosphate (IP3), which is produced in response to various stimuli by the action of phospholipase C enzymes. Very soon after the discovery that IP3 is a calcium mobilizing second messenger, it was found that T‐cell receptor signaling is dependent upon IP3R activity. It is now known that cell signaling throughout the immune system is dependent upon IP3R‐dependent calcium release for many critical processes, including cellular activation, proliferation, and death. This channel plays a critical role in orchestrating the immune response in health and disease and thus offers potential as a therapeutic target in immune‐related disorders. WIREs Membr Transp Signal 2012,1:329–339. doi: 10.1002/wmts.27

For further resources related to this article, please visit the WIREs website.
An Update on the Use of Co‐products from the Milling of Rice in Value‐Added Food Products
Authors: Shih Fred F.
Published: October 2011

Because of the large amount of rice produced annually, milled rice co‐products, such as rice flour, rice bran, rice bran oil, wax, and rice hulls are plentiful and readily available. These co‐products are valuable sources of food ingredients, but they are currently under‐utilized. Rice bran and flour contain different levels of protein. When treated with carbohydrate‐hydrolyzing enzymes, high‐protein products can be produced, which are nutritious and used widely in health and baby food formulations. Recently, subcritical water processing has also been studied, in which water is put under high pressure to maintain its liquid state and used as an environmental‐friendly media for the recovery of rice bran proteins. Rice flour contains more than 90% rice starch (RS), and functional properties of RS are normally modified to suit the needs for food applications. For example, the addition of small amounts of phosphorylated RS esters or pregelatinized rice flour to frying batters made of rice flour was found to impart superior sensory characteristics and lower the amount of oil‐uptake. Reductions in oil uptake of up to 50% were observed with the rice based formulations compared with batters made from traditional wheat ingredients. Treatment of RS with octenylsuccinic anhydride produces modified starch products that are useful as an emulsifying agent for the encapsulation of lipophilic compounds. Similarly, other rice‐based products, such as microcrystalline celluloses from rice hulls, edible films formed with rice wax, various components with antioxidant properties, and germinated brown rice flours have also been developed.
Estimation of Oil Content and Fatty Acid Composition in Cottonseed Kernel Powder Using Near Infrared Reflectance Spectroscopy
Authors: Quampah Alfred , Huang Zhuang Rong , Wu Jian Guo , Liu Hai Ying , Li Jin Rong , Zhu Shui Jin , Shi Chun Hai
Published: October 2011

Oil content and fatty acid composition in 444 ground cottonseed kernel samples were analyzed using near infrared reflectance spectroscopy (NIRS). Calibration equations were developed for oil and fatty acid contents with the modified partial least squares (MPLS) regression method. The correlations between NIRS and reference values in external validation were in agreement with the predictions in calibration. Each equation was assessed based on the relative prediction determinant for external validation (RPDv). Equations corresponding to total oil content (RPDv = 11.495) and linoleic acid (RPDv = 5.026) showed high accuracy. For palmitic acid (RPDv = 1.914), myristic acid (RPDv = 1.724) and oleic acid (RPDv = 1.999), the equations were predicted with relatively high accuracy while those for palmitoleic acid (RPDv = 0.686), stearic acid (RPDv = 0.792), linolenic acid (RPDv = 0.475) and 1‐eicosenoic acid (RPDv = 0.619) were poorly predicted. The equations for traits with RPDv > 1.5 could be reliably used in screening samples for breeding programs.
Biochemistry of Citric Acid Production from Rapeseed Oil by Yarrowia lipolytica Yeast
Authors: Kamzolova Svetlana V. , Lunina Julia N. , Morgunov Igor G.
Published: October 2011

The growth of wild type strain Yarrowia lipolytica VKM Y‐2373 and its mutant Y. lipolytica NG40/UV7 as well as the biosynthesis of citric and isocitric acid on rapeseed oil were studied. It was indicated that the initial step of assimilation of rapeseed oil in the yeast Y. lipolytica is its hydrolysis by extracellular lipases with the formation of glycerol and fatty acids, which appear in the medium in the phase of active growth. The concentrations of these metabolites were changed insignificantly upon further cultivation. Lipase and the key enzymes of glycerol metabolism (glycerol kinase) and the glyoxylate cycle responsible for the metabolism of fatty acids (isocitrate lyase and malate synthase) are induced just at the beginning of the growth phase and remain active in the course of further cultivation. These results, taken together, suggest that glycerol and fatty acids available in the medium do not suppress the metabolism of each other. Citric acid production and a ratio between citric and isocitric acids depended on the strain used. It was revealed that the wild strain produced almost equal amounts of citric and isocitric acids while the mutant produced only citric acid (175 g/L) with a yield of 1.5 g of CA per g of oil.
Antioxidant Activities and Oxidative Stabilities of Some Unconventional Oilseeds
Authors: Uluata Sibel , Özdemir Nurhayat
Published: October 2011

The oils of some unconventional oilseeds (hemp, radish, terebinth, stinging nettle, laurel) were obtained by a cold‐press method in which the total oil content, fatty acids, tocopherol isomers, some metal contents (Ca, Mg, Fe, Cu), antioxidant activity and oxidative stability were determined. The total oil content was determined ranging between 30.68 and 43.12%, and the oil samples had large amounts of unsaturated fatty acids, with oleic acid and linoleic acid. Of all the oils, terebinth seed oil had the highest α‐tocopherol content (102.21 ± 1.01 mg/kg oil). Laurel oilseed had the highest antiradical activity in both the DPPH and ABTS assays. The peroxide value of the non‐oxidized oils ranged between 0.51 and 3.73 mequiv O2/kg oil. The TBARS value of the non‐oxidized oils ranged between 0.68 ± 0.02 and 6.43 ± 0.48 mmol MA equiv/g oil. At 110 °C, the Rancimat induction period of the oils ranged between 1.32 and 43.44 h. The infrared spectra of the samples were recorded by FTIR spectroscopy. The absorbance values of the spectrum bands were observed and it was determined that some of the chemical groups of oxidized oils caused changes in absorbance. As a result of the present research, the analyzed oils could be evaluated as an alternative to traditionally consumed vegetable oils or as additives to them.
Focal adhesion kinase inhibitors are potent anti‐angiogenic agents
Authors: Cabrita Miguel A. , Jones Laura M. , Quizi Jennifer L. , Sabourin Luc A. , McKay Bruce C. , Addison Christina L.
Published: October 2011

Focal adhesion kinase (FAK), a cytoplasmic tyrosine kinase and scaffold protein localized to focal adhesions, is uniquely positioned at the convergence point of integrin and receptor tyrosine kinase signal transduction pathways. FAK is overexpressed in many tumor cells, hence various inhibitors targeting its activity have been tested for anti‐tumor activity. However, the direct effects of these pharmacologic agents on the endothelial cells of the vasculature have not been examined. Using primary human umbilical vein endothelial cells (HUVEC), we characterized the effects of two FAK inhibitors, PF‐573,228 and FAK Inhibitor 14 on essential processes for angiogenesis, such as migration, proliferation, viability and endothelial cell tube formation. We observed that treatment with either FAK Inhibitor 14 or PF‐573,228 resulted in reduced HUVEC viability, migration and tube formation in response to vascular endothelial growth factor (VEGF). Furthermore, we found that PF‐573,228 had the added ability to induce apoptosis of endothelial cells within 36 h post‐drug administration even in the continued presence of VEGF stimulation. FAK inhibitors also resulted in modification of the actin cytoskeleton within HUVEC, with observed increased stress fiber formation in the presence of drug. Given that endothelial cells were sensitive to FAK inhibitors at concentrations well below those reported to inhibit tumor cell migration, we confirmed their ability to inhibit endothelial‐derived FAK autophosphorylation and FAK‐mediated phosphorylation of recombinant paxillin at these doses. Taken together, our data indicate that small molecule inhibitors of FAK are potent anti‐angiogenic agents and suggest their utility in combinatorial therapeutic approaches targeting tumor angiogenesis.
Summer–winter transitions in Antarctic ponds: III. Chemical changes
Authors: Webster-Brown Jenny , Hawes Ian , Safi Karl , Sorrell Brian , Wilson Nathaniel
Published: October 2011

Observations were made of water column chemistry in four Na-Cl dominated ponds on the McMurdo Ice Shelf from the end of January to early April in 2008. During that time the ponds went from ice-free to predominantly frozen, with only a small volume of residual hypoxic, saline liquid trapped at the base of each pond. Changes in the concentrations of inorganic solutes with time distinguished Na, Cl, Mg, K, SO4, As, U and Mn as ions and trace elements that behave mainly conservatively during freezing, from those which are affected by biological processes (removing HCO3) and the precipitation of mineral phases such as calcite (removing Ca and more HCO3). Dissolved Fe, Mo, Cu and Zn also show evidence of precipitation from the water column during freezing; geochemical speciation modelling predicts the formation of stable insoluble mineral phases such as Fe oxides and oxyhydroxides while conditions are oxic, and Fe-, Cu-, Mo- and Zn-sulphide minerals in the presence of H2S. Consequently, under winter conditions, residual liquid beneath the ice in such ponds is anticipated to be an anoxic Na-Cl brine with the capacity to develop high concentrations of toxic trace elements such as As and U.
Alters- und geschlechtspezifische Neunormierung der Fragen zur Lebenszufriedenheit (FLZM) für die Altersspanne von 14 bis 64 Jahre
Authors: Daig Isolde , Spangenberg Lena , Henrich Gerhard , Herschbach Peter , Kienast Thorsten , Brähler Elmar
Published: October 2011

Zusammenfassung. Theoretischer Hintergrund: Der FLZM-Fragebogen (Fragen zur Lebenszufriedenheit) ist ein ökonomisches, reliables Verfahren zur Erfassung der allgemeinen Lebenszufriedenheit. Fragestellung: Die vorhandenen Normwerte sind über 10 Jahre alt, zudem fehlen bislang Angaben über Prozentränge. Methode: Die vorliegende Studie stellt eine alters- und geschlechtsspezifische Neunormierung anhand einer bevölkerungsrepräsentativen Stichprobe aus Deutschland für den Altersbereich 14 bis 64 Jahre vor (N = 3877). Ergebnisse: Mittelwerte, Standardabweichungen, Trennschärfeindices und Prozentränge werden für Alter und Geschlecht getrennt berichtet. Die Ergebnisse zeigen gute interne Konsistenzen für die gewichtete (Cronbachs Alpha = 0,83) wie auch für die ungewichtete Lebenszufriedenheit (Cronbachs Alpha = 0,82). Schlussfolgerungen: Für die FLZM liegen aktualisierte Normdaten vor. Für einen Einsatz des Messinstruments können nun aktuelle Vergleichsdaten der gesamtdeutschen Bevölkerung zwischen 14–64 Jahren herangezogen werden.
Fluorescence enhancement of light-harvesting complex 2 from purple bacteria coupled to spherical gold nanoparticles
Authors: Bujak Ł. , Czechowski N. , Piatkowski D. , Litvin R. , Mackowski S. , Brotosudarmo T. H. P. , Cogdell R. J. , Pichler S. , Heiss W.
Published: October 2011

The influence of plasmon excitations in spherical gold nanoparticles on the optical properties of a light-harvesting complex 2 (LH2) from the purple bacteria Rhodopseudomonas palustris has been studied. Systematic analysis is facilitated by controlling the thickness of a silica layer between Au nanoparticles and LH2 complexes. Fluorescence of LH2 complexes features substantial increase when these complexes are separated by 12 nm from the gold nanoparticles. At shorter distances, non-radiative quenching leads to a decrease of fluorescence emission. The enhancement of fluorescence originates predominantly from an increase of absorption of pigments comprising the LH2 complex.
An empirical pseudopotential approach to surface and line-edge roughness scattering in nanostructures: Application to Si thin films and nanowires and to graphene nanoribbons
Authors: Fischetti Massimo V. , Narayanan Sudarshan
Published: October 2011

We present a method to treat scattering of electrons with atomic roughness at interfaces, surfaces, and edges on nanometer-scale structures based on local empirical pseudopotentials. This approach merges the computational advantages of macroscopic models based on the shift of a phenomenological “barrier potential,” with the physical accuracy of models based on modifications of the atomic configuration at the interface/surface/edge. We illustrate the method by considering the dependence of the scattering matrix element on the confinement (inversion) field in free-standing H-terminated Si inversion layers, on the thickness in similarly H-terminated thin-Si bodies, on the diameter of free-standing [100] cylindrical Si nanowires, and on the width of armchair-edge graphene nanoribbons. For these latter structures, we find extremely large scattering rates, whose magnitude — ultimately due to the chirality dependence of the bandgap — renders perturbation theory invalid and prevents us from drawing quantitative conclusions about transport properties. Yet, they show clearly the dominant role played by line-edge roughness in controlling electronic transport in these structures, in agreement with suggestions that transport in narrow and rough ribbons does not occur via extended Bloch states.
Electron-beam direct processing on living cell membrane
Authors: Hoshino Takayuki , Morishima Keisuke
Published: October 2011

We demonstrated a direct processing on a living Hep G2 cell membrane in conventional cultivation conditions using an electron beam. Electron beam-induced deposition from liquid precursor 3,4-ethylenedioxythiophene and ablation was performed on the living cells. The 2.5-10 keV electron beam which was irradiated through a 100-nm-thick SiN nanomembrane could induce a deposition pattern and a ablation on a living cell membrane. This electron beam direct processing can provide simple in-situ cell surface modification for an analytical method of living cell membrane dynamic.
Stability of heterophase nanostructure and field induced response of epitaxial ferroelectric films
Authors: Roytburd Alexander L. , Ouyang Jun , Boyerinas Brad M. , Bruck Hugh A.
Published: October 2011

The concept of elastic domains is extended to heterophase ferroelectric epitaxial films undergoing phase transformation. Equilibrium nanostructure of ferroelectric phases forming heterophase polydomains, including their relative domain fraction, the distortion of phases, and the orientation of domain interfaces, is determined. The enhanced field induced response of polydomain nanostructures to external field due to domain interface movement is estimated. As an example, rhombohedral-tetragonal polydomain nanostructures in ferroelectric BiFeO3 film are considered.
Linear relations among holomorphic quadratic differentials and induced Siegel's metric on $\mathcal {M}_g$Mg
Authors: Matone Marco , Volpato Roberto
Published: October 2011

We find the explicit form of the volume form on the moduli space of non-hyperelliptic Riemann surfaces induced by the Siegel metric, a long-standing question in string theory. This question is related to the explicit form of the (g−2)(g−3)/2 linearly independent relations among the 2-fold products of holomorphic abelian differentials, that are provided in the case of canonical curves of genus g ⩾ 4. Such relations can be completely expressed in terms of determinants of the standard normalized holomorphic abelian differentials. Remarkably, it turns out that the induced volume form is the Kodaira-Spencer map of the square of the Bergman reproducing kernel.
A correlated electron diffraction, in situ neutron diffraction and dielectric properties investigation of poled (1-x)Bi0.5Na0.5TiO3-xBaTiO3 ceramics
Authors: Wang Jian , Liu Yun , Withers Ray L. , Studer Andrew , Li Qian , Norén Lasse , Guo Yiping
Published: October 2011

A correlated electron diffraction, temperature-dependent in situ neutron diffraction, and temperature-dependent dielectric properties investigation of poled (1-x)Bi0.5Na0.5TiO3-xBaTiO3 (BNTBT100x) (x = 0.04, 0.07, and 0.12) samples has been carried out. The results show that the depolarization temperature, Td, of the rhombohedral BNTBT 4 sample is associated with the disappearance of G ± ½ [111]*p satellite reflections and a-a-a- octahedral tilting while that of the BNTBT 12 sample is associated with a metrically tetragonal to metrically cubic or pseudo-cubic symmetry. In the case of the poled BNTBT 7 sample in the MPB region, the dielectric properties show a quite distinct two stage transition from a room temperature clearly metrically tetragonal phase again to a metrically cubic or pseudo-cubic symmetry above 150 °C. There is no apparent change in its average structure in vicinity of Td in BNTBT 7. Electron diffraction shows the presence of considerable octahedral tilt twin disorder in all three samples.
Polarization dependent study of gain anisotropy in semipolar InGaN lasers
Authors: Rass Jens , Wernicke Tim , Ploch Simon , Brendel Moritz , Kruse Andreas , Hangleiter Andreas , Scheibenzuber Wolfgang , Schwarz Ulrich T. , Weyers Markus , Kneissl Michael
Published: October 2011

The optical gain of single quantum well laser structures on semipolar (112¯2)-GaN in dependence of the optical polarization and the resonator orientation has been studied by variable stripe length method. The c′-[1123¯] resonator shows maximum gain in TE mode, followed by the m-[11¯00]-resonator with extraordinary polarization. The anisotropic gain behaviour is explained by valence sub-band ordering and birefringence of the wurtzite crystal, resulting in a modification of the transition matrix element for stimulated emission. Measurements are accompanied by 6 × 6 k · p band structure calculations and gain analysis.
Performance analysis of carbon nanotube contacted phase change memory by finite element method
Authors: Chen Wenchao , Guo Jing
Published: October 2011

Carbon nanotube (CNT) contacted phase change memory (CCPCM) has been experimentally demonstrated recently. In this work, a simplified two-dimensional (2D) model which is mapped from the three-dimensional (3D) structure of CNT-contacted phase change memory (CCPCM) is proposed and validated. In addition to two to three orders lower programming current and power, a transient analysis shows that CCPCM has much quicker response time to programming current pulse showing potential for lower programming time. We also find there is an optimum design for the gap size between CNT contacts, but the relatively small resistivity and gap size may affect the detection of amorphous state and crystalline state. Scaling analysis shows that scaling down the CNT diameter plays the most important role on improving device performance, and a set/reset power as low as 1 μW/1.5 μW is achievable with a CNT diameter of 1 nm.
Maintaining Existing Zoning Systems Using Automated Zone-Design Techniques: Methods for Creating the 2011 Census Output Geographies for England and Wales
Authors: Cockings Samantha , Harfoot Andrew , Martin David , Hornby Duncan
Published: October 2011

Automated zone-design methods are increasingly being used to create zoning systems for a range of purposes, such as the release of census statistics or the investigation of neighbourhood effects on health. Inevitably, the characteristics originally underpinning the design of a zoning system (eg, population size or homogeneity of the built environment) change through time. Rather than designing a completely new system every time substantive change occurs, or retaining an existing system which will become increasingly unfit for purpose, an alternative is to modify the existing system such that zones which still meet the design criteria are retained, but those which are no longer fit for purpose are split or merged. This paper defines the first generic methodology for the automated maintenance of existing zoning systems. Using bespoke, publicly available, software (AZTool), the methodology is employed to modify the 2001 Census output geographies within six local authority districts in England and Wales in order to make them suitable for the release of contemporary population-related data. Automated maintenance of an existing system is found to be a more iterative and constrained problem than designing a completely new system; design constraints frequently have to be relaxed and manual intervention is occasionally required. Nonetheless, existing zone-design techniques can be successfully adapted and implemented to automatically maintain an existing system. The findings of this paper are of direct relevance both to the Office for National Statistics in their design of the 2011 Census output geographies for England and Wales and to any other countries or organisations seeking to maintain an existing zoning system.
Constraints on the recovery of invertebrate assemblages in a regulated snowmelt river during a tributary-sourced environmental flow regime
Authors: Brooks Andrew J. , Russell Matthew , Bevitt Robyn , Dasey Matthew
Published: October 2011

The impacts of river regulation on aquatic biota have been extensively studied, but long-term assessments of the restoration of biota by environmental flows and the principal mechanisms of recovery have rarely occurred. We assessed whether the provision of an environmental flow regime (EFR) via the decommissioning of an aqueduct on a tributary stream altered downstream macroinvertebrate assemblages in the highly regulated Snowy River, Australia. Macroinvertebrate assemblages of the Snowy River, reference and control sites remained distinct despite the provision of environmental flows. Invertebrate assemblages detrimentally affected by regulation probably remained impaired due to either constraints on colonisation from the tributary stream (dispersal constraints) or unsuitable local environmental conditions in the Snowy River caused by flow regulation (e.g. high levels of fine sediments, elevated temperature regime) suppressing new colonists or recovery of extant populations. Our study showed that restoration may be ineffective if EFRs are too small to ameliorate local environmental factors constraining the recovery of affected biota. Other barriers to recovery, such as dispersal constraints, also need to be overcome. Successful restoration of regulated rivers using environmental flows requires an understanding of the mechanisms and pathways of recovery, together with identification and amelioration of any potential barriers to recovery.
Post-fire soil fluxes of CO2, CH4 and N2O along the Colorado Front Range
Authors: Gathany Mark A. , Burke Ingrid C.
Published: October 2011

Wildfires affect Rocky Mountain ecosystems across a wide range of spatial and temporal scales. Many of the resulting changes are greatest for environmental factors, such as substrate and microclimate that control exchanges of greenhouse gases. We investigated this link to understand how time since fire influences the cycling of these gases through ponderosa pine forests. We measured and compared trace gas flux rates between recently burned sites and topographical aspects (north- and south-facing slopes). We calculated the ability of five factors (soil temperature, soil moisture, fire severity, aspect and time since fire) to describe the variability in the flux rates. Our study revealed that carbon dioxide (CO2) fluxes were significantly different between sites; however, methane (CH4) uptake was not different between sites or aspects. Nitrous oxide (N2O) fluxes had a significant interaction between site and aspect. Using a likelihood approach, we determined the strength of support in the data for model combinations of five variables. Of these, the single variable models soil moisture, time since fire and severity best described the CO2, CH4, and N2O flux data respectively. Our data show that following a forest fire in the Colorado Front Range, >98% of the global warming potential of the measured soil–atmosphere fluxes is contributed by the soil CO2 flux.
Long-term effects of fire and three firefighting chemicals on a soil - plant system
Authors: Couto-Vázquez A. , García-Marco S. , González-Prieto S. J.
Published: October 2011

The effects of fire and firefighting chemicals on soil properties and the soil–plant system were evaluated 5 years after treatment application. Unburnt soils were compared with burnt soils treated with water alone (BS) or with foaming agent (BS+Fo), Firesorb polymer (BS+Fi), or ammonium polyphosphate (BS+Ap). Soils (0–2 cm depth) and foliar material (Ulex micranthus, Pterospartum tridentatum, Erica umbellata and Pinus pinaster) were analysed for total C, total N, δ15N, nutrients (soil-available; plant total), pH and inorganic-N (soils) and vegetation cover and height. No long-term effects of firefighting chemicals on soil properties were found except for pH (BS+Fo > BS+Ap), inorganic-N and P (BS+Ap > other treatments). BS+Ap plants usually showed higher values of δ15N, N, P and Na, but less K. Soil coverage by Pterospartum and Ulex was higher in BS+Ap than in other treatments, whereas the opposite was observed for Erica; shrubs were always taller in BS+Ap. After 3 years of growth, the size of pine seedlings followed the order BS+Ap > unburnt soil > other treatments. Foliar N and P, scrub regeneration and growth of pines showed the long-term fertilising effect of ammonium polyphosphate, although the second highest pine mortality was found in the BS+Ap treatment. The foaming agent did not affect vegetation cover, and Firesorb had no noticeable effect on shrubs but the highest pine mortality.
Short-term effects of prescribed burning on radial growth of Douglas-fir trees in south central British Columbia
Authors: Feller M. C. , Klenner W.
Published: October 2011

Radial increment of Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) trees in uncut and partially cut and grazed and ungrazed dry cool Interior Douglas-fir forests near Isobel Lake in southern central British Columbia was measured for 2-year periods before and after prescribed burning in burned and unburned (control) areas. Parameters thought to influence the effects of prescribed burning on tree growth – characteristics of the tree and its immediate environment, adjacent surface and ladder fuels, and fire effects – were also measured. Burning caused a decrease in tree radial growth. The proportional change in radial tree growth was not related to degree of cutting or the presence of cattle grazing, but was negatively correlated with preburn radial growth, tree size, and also with some fire effect variables, particularly char height, suggesting that an increasing proportional decline in radial growth was associated with increasing tree size and with increasing fire severity. Soil nutrient (N, S, P, K, Mg or Ca) level was not a significant determinant of tree growth. The best prediction model could only explain 23% of the variation in the change in radial growth. Our results show that the effects of fire on Douglas-fir radial growth are complex and difficult to predict with the variables measured.