bluuebunny/crossref_metadata_2025 huggingface dataset:
Practice‐oriented probabilistic seismic performance assessment of infilled frames with consideration of shear failure of columns
Authors: Celarec Daniel , Dolšek Matjaž
Published: December 2012

The objective of the study presented in this paper is to investigate the effects of masonry infills on the shear demand and failure of columns for the case when reinforced concrete frames with such infills are modeled by means of simplified nonlinear models that are not capable of the direct simulation of these effects. It is shown that an approximate simulation of the shear failure of columns can be achieved through an iterative procedure that involves pushover analysis, post‐processing of the analysis results using limit‐state checks of the components, and model adaptation if shear failure of columns is detected. The fragility parameters and the mean annual frequency of limit‐state exceedance are computed on the basis of nonlinear dynamic analysis by using an equivalent SDOF model. The proposed methodology is demonstrated by means of two examples. It was shown that the strength of the four‐story and seven‐story buildings and their deformation capacity are significantly overestimated if column shear failure due to the effects of masonry infills is neglected, whereas the mean annual frequency of limit‐state exceedance for the analyzed limit states is significantly larger than that estimated for the case if the shear failure of columns is neglected. Copyright © 2012 John Wiley & Sons, Ltd.
Combined toxicity of polycyclic aromatic hydrocarbons and heavy metals to biochemical and antioxidant responses of free and immobilized Selenastrum capricornutum
Authors: Wang Ping , Luo Lijuan , Ke Lin , Luan Tiangang , Tam Nora Fung-Yee
Published: December 2012

The aquatic environment often contains different groups of contaminants, but their combined toxicity on microalgae has seldom been reported. The present study compared the toxic effects of combined mixed polycyclic aromatic hydrocarbons (PAHs) and heavy metals on growth and antioxidant responses of free and immobilized microalga, Selenastrum capricornutum. Five PAHs—phenanthrene, fluorene, fluoranthene, pyrene, and benzo[a]pyrene—and four heavy metals at different concentrations—0.05 to 0.1 µg Cd2+ ml−1, 0.05 to 1 µg Cu2+ ml−1, 0.05 to 1 µg Zn2+ ml−1, and 0.5 to 2.5 µg Ni2+ ml−1—were examined. Results showed that the chlorophyll a content of free and immobilized S. capricornutum was not affected by PAHs but was significantly inhibited by heavy metals. Conversely, the antioxidant parameters, including the content of reduced glutathione (GSH) and the activities of superoxide dismutase and peroxidase, were significantly induced by both PAHs and metals. For the combined toxic effects of PAHs and heavy metals, cell growth and antioxidant responses varied with exposure time and contaminants and differed between free and immobilized cells. The effects of cocontaminants on the GSH content in free cells were mainly synergistic but changed to antagonistic in immobilized cells. The toxic effects of cocontamination on free cells were also more obvious than those on immobilized cells. These findings suggest that immobilization offers some protection to microalgal cells against toxic contaminants causing differences in the interaction and responses to combined toxicants between free and immobilized cells. Immobilized cells might be more suitable for treating wastewater containing toxic contaminants than free cells. Environ. Toxicol. Chem. 2013;32:673–683. © 2012 SETAC
Regional inhibition of cholinesterase in free-ranging western pond turtles (Emys marmorata) occupying California mountain streams
Authors: Meyer Erik , Sparling Donald , Blumenshine Steve
Published: December 2012

The present study investigated the potential effects of cholinesterase (ChE)-inhibiting pesticides on western pond turtles (Emys marmorata) occupying streams in two regions of California, USA. The southern region was suspected of having increased exposure to atmospheric deposition of contaminants originating from Central Valley agriculture. The northern region represented reference ChE activities because this area was located outside of the prominent wind patterns that deposit pesticides into the southern region. Total ChE activity was measured in plasma from a total of 81 turtles from both regions. Cholinesterase activity of turtles was significantly depressed by 31% (p = 0.005) in the southern region after accounting for additional sources of variation in ChE activity. Male turtles had significantly increased ChE activity compared with females (p = 0.054). Cloaca temperature, length, mass, handling time, body condition, and lymph presence were not significant predictors of turtle ChE activity. In the southern region, 6.3% of the turtles were below the diagnostic threshold of two standard deviations less than the reference site mean ChE activity. Another diagnostic threshold determined that 75% of the turtles from the southern region had ChE activities depressed by 20% of the reference mean. The decrease in ChE activity in the southern region suggests sublethal effects of pesticide exposure, potentially altering neurotransmission, which can result in various deleterious behaviors. Environ. Toxicol. Chem. 2013;32:692–698. © 2012 SETAC
Empowering the voice of youth: The role of youth advisory councils in grant making focused on youth
Authors: Richards‐Schuster Katie
Published: December 2012

This article will focus on the potential role for youth evaluation advisory groups within youth grant‐making organizations and networks. The main elements to be discussed include the formation of the network, the training program elements, some specific examples of efforts by young people to create and strengthen evaluation within their YACs (youth advisory councils), and the lessons learned. ©Wiley Periodicals, Inc., and the American Evaluation Association.
Chemical composition of the giant red sea cucumber, Parastichopus californicus, commercially harvested in Alaska
Authors: Bechtel Peter J. , Oliveira Alexandra C. M. , Demir Necla , Smiley Scott
Published: December 2012

Giant red sea cucumbers, Parastichopus californicus, are commercially harvested in the U.S. Pacific Northwest; however, the nutritional and chemical properties of its edible muscle bands and body wall have not been fully elucidated. In particular are the fatty acid profiles of P. californicus tissues, which have not been documented. Sea cucumbers were delivered live and muscle bands and body wall freeze dried, vacuum packed, and stored at −30°C until analyzed. Proximate composition of freeze‐dried tissues varied greatly with muscle bands being composed of 68% protein, 12% ash, 9% carbohydrate, and 5% lipids, while the body wall was composed of 47% protein, 26% ash, 15% carbohydrate, and 8% lipids. The hydroxyproline, proline, and glycine contents of the body wall were much higher than those in muscle bands, consistent with the larger amount of connective tissue. Calcium, magnesium, sodium, and iron contents were higher in the body wall than those in muscle bands, whereas the opposite was observed for zinc content. Total long‐chain n‐3 fatty acid contents were 19% and 32% of total fatty acids in body wall and muscle bands, respectively. Muscle bands had higher content of eicosapentaenoic acid (20:5n‐3) than body wall at 22.6% and 12.3%, respectively. High content of arachidonic acid (20:4n‐6) was recorded in both body wall (7.1%) and muscle bands (9.9%). Overall, the fatty acid profiles of body wall and muscle bands of P. californicus resemble those described for other species; however, the distribution and occurrence of certain fatty acids is unique to P. californicus, being representative of the fatty acid composition of temperate‐polar marine organisms. The chemical characterization of freeze‐dried edible tissues from P. californicus demonstrated that these products have valuable nutritional properties. The body wall, a food product of lower market value than muscle bands, could be better utilized for nutraceutical and pharmaceutical applications.
Cinnamon extract inhibits angiogenesis in zebrafish and human endothelial cells by suppressing VEGFR1, VEGFR2, and PKC‐mediated MAP kinase
Authors: Bansode Rishipal R. , Leung TinChung , Randolph Priscilla , Williams Leonard L. , Ahmedna Mohamed
Published: December 2012

Angiogenesis is a process of new blood vessel generation and under pathological conditions, lead to tumor development, progression, and metastasis. Many bioactive components have been studied for its antiangiogenic properties as a preventive strategy against tumor development. This study is focused on the effects of cinnamon extract in modulating the pathway involved in angiogenesis. Human umbilical vein endothelial cells (HUVEC) were treated with cinnamon extract at a concentration of 25 μg/mL for 1, 3, or 6 h followed by treatment with phorbol ester (TPA) at a concentration of 10 nmol/L to induce mitogen‐activated protein kinase (MAPK) expression. Results show that cinnamon extract inhibited TPA‐induced phosphorylation of MAPK and AKT in a dose‐dependent manner. Gene expression results in HUVEC showed that cinnamon extract treatment inhibited TPA induction of protein kinase C, PKCα and PKCη messenger RNA (mRNA) expression in a dose‐dependent manner along with suppression of vascular endothelial growth factor receptor 1 (VEGFR1/Flt1) and vascular endothelial growth factor receptor 2 (VEGFR2/KDR/Flk1) mRNA expression. Cinnamon extract was administered to zebrafish embryos during gastrulation at 6–8 h post fertilization (hpf). The embryos were observed for changes in morphology, toxicity, and blood vessel development. The intersegmental vessels in the zebrafish embryos were attenuated and underdeveloped at an effective cinnamon extract dose of 250 μg/mL compared with the DMSO‐treated control. Exposure to cinnamon extract for 36 h resulted in gross morphological deformities. The results suggest the effect of cinnamon extract on angiogenesis is mediated by PKC‐dependent phosphorylation of MAPK.
The role of activation functions 1 and 2 of estrogen receptor-α for the effects of estradiol and selective estrogen receptor modulators in male mice
Authors: Börjesson Anna E , Farman Helen H , Engdahl Cecilia , Koskela Antti , Sjögren Klara , Kindblom Jenny M , Stubelius Alexandra , Islander Ulrika , Carlsten Hans , Antal Maria Cristina , Krust Andrée , Chambon Pierre , Tuukkanen Juha , Lagerquist Marie K , Windahl Sara H , Ohlsson Claes
Published: December 2012

Estradiol (E2) is important for male skeletal health and the effect of E2 is mediated via estrogen receptor (ER)-α. This was demonstrated by the findings that men with an inactivating mutation in aromatase or a nonfunctional ERα had osteopenia and continued longitudinal growth after sexual maturation. The aim of the present study was to evaluate the role of different domains of ERα for the effects of E2 and selective estrogen receptor modulators (SERMs) on bone mass in males. Three mouse models lacking either ERαAF-1 (ERαAF-10), ERαAF-2 (ERαAF-20), or the total ERα (ERα−/−) were orchidectomized (orx) and treated with E2 or placebo. E2 treatment increased the trabecular and cortical bone mass and bone strength, whereas it reduced the thymus weight and bone marrow cellularity in orx wild type (WT) mice. These parameters did not respond to E2 treatment in orx ERα−/− or ERαAF-20 mirx ERαAF-10 mice were tissue-dependent, with a clear response in cortical bone parameters and bone marrow cellularity, but no response in trabecular bone. To determine the role of ERαAF-1 for the effects of SERMs, we treated orx WT and ERαAF-10 mice with raloxifene (Ral), lasofoxifene (Las), bazedoxifene (Bza), or vehicle. These SERMs increased total body areal bone mineral density (BMD) and trabecular volumetric BMD to a similar extent in orx WT mice. Furthermore, only Las increased cortical thickness significantly and only Bza increased bone strength significantly. However, all SERMs showed a tendency toward increased cortical bone parameters. Importantly, all SERM effects were absent in the orx ERαAF-10 mice. In conclusion, ERαAF-2 is required for the estrogenic effects on all evaluated parameters, whereas the role of ERαAF-1 is tissue-specific. All evaluated effects of Ral, Las and Bza are dependent on a functional ERαAF-1. Our findings might contribute to the development of bone-specific SERMs in males. © 2013 American Society for Bone and Mineral Research.
Direct Determination of Arsenic in Beet Sugar Molasses Using Nickel as Chemical Modifier by Electrothermal Atomic Absorption Spectrommetry
Authors: Pourhossein Alireza , Shahlaei Mohsen
Published: December 2012

A simple electrothermal atomic absorption spectrometric (ETAAS) method is described for direct determination of arsenic in sugar beet molasses samples. Pyrolytic graphite tubes were used as atomizers. The compression between modifiers such as nickel nitrate, palladium nitrate and the mixture of palladium and magnesium nitrate were performed and nickel nitrate selected as the best chemical modifier. The effects of pyrolysis and atomization temperature were also studied and the pyrolysis temperature of 900 °C and atomization temperature of 2300 °C have been chosen for temperature program. The detection limit of the method was 1 ng/mL As in sugar beet molasses samples. The relative standard deviation for ten determination of a spiked sample with concentration of 50 ng/mL As was 2.4%. The accuracy of the method was confirmed by the analysis of spiked samples. The linear rang of calibration is in the range of 1‐100 ng/mL of arsenic.
Ionic liquids and deep eutectic solvents for biodiesel synthesis: a review
Authors: Zhao Hua , Baker Gary A.
Published: December 2012

During the past decade, ionic liquids (ILs) have gained tremendous attention in nearly every branch of the chemical and physical sciences as designer (task‐driven) and budding ‘green’ solvent alternatives to conventional volatile organics. In particular, with a more in‐depth understanding of their physicochemical properties, the active exploration of ILs as alternative solvents and/or catalysts in the chemical or enzymatic (biocatalytic) production of biodiesel has gained momentum. Most excitingly, very recent developments in the science of deep eutectic solvents (DESs) have initiated potentially more cost‐effective approaches to biodiesel synthesis. At this stage, there is sufficient research completed to provide an important opportunity to stand back and assess the progress in the field, critically examining the strengths and limitations for IL and DES technology in biodiesel synthesis. No such comprehensive evaluation exists. This work, therefore, seeks to bridge this gap by systematically reviewing the reported methods for biodiesel production which make use of ILs, either as (co)solvent components or catalysts, highlighting existing problems and limitations, with an emphasis placed on the future research required to bypass the hurdles to employing ILs in commercial biodiesel production. Copyright © 2012 Society of Chemical Industry
Synthesis and characterization of TiO2 nanotube photoanode and its application in photoelectrocatalytic degradation of model environmental pharmaceuticals
Authors: Nie Xin , Chen Jiangyao , Li Guiying , Shi Huixian , Zhao Huijun , Wong Po‐Keung , An Taicheng
Published: December 2012

BACKGROUND

In this study, highly ordered titanium dioxide (TiO2) nanotube arrays with tunable inner‐diameter and morphology were synthesized by an anodizing method from titanium (Ti) foil by optimizing different preparation parameters, and acyclovir was degraded to test the photoelectrocatalytic activity of prepared nanotubes in a thin layer reactor.

RESULTS

The results indicated that anodization time, the concentrations of NH4F and HAc had significant effect on the surface morphology and inner‐diameter of TiO2 nanotubes. Various morphologies including honeycomb films and nanotube arrays were obtained under given conditions. Photoelectrocatalysis showed higher degradation efficiency than that of photocatalysis or electrolysis due to TiO2 nanotubes regular nanotubular effectively reducing the recombination of photo‐generated electron–hole pairs. The photoelectrochemical responses and degradation efficiencies of acyclovir were well related to the TiO2 crystallinity and morphology of TiO2 nanotube photoanodes. Regular nanotube array photoanodes displayed better crystallinity, higher photoelectrochemical response and higher photoelectrocatalytic activity than those of nanopore photoanodes. The best TiO2 nanotube photoanode was prepared at 30 V for 24 h in the ethylene glycol solution containing 0.20 mol L−1 NH4F and 0.50 mol L−1 HAc.

CONCLUSION

TiO2 nanotube photoelectrocatalysis technology is an effective way to decontaminate organic contaminants in water. © 2012 Society of Chemical Industry
Assessment of hydrogen isotopic compositions of n‐fatty acids as paleoclimate proxies in Lake Biwa sediments
Authors: Seki Osamu , Kawamura Kimitaka , Ishiwatari Ryoshi
Published: December 2012

Compound specific hydrogen isotopic compositions (δD) of free and bound forms of n‐fatty acids (FA) were measured throughout a 200 m sediment core taken from Lake Biwa to assess application of biomarker δD values to paleoclimate study in this central Japan lake. The results of our study suggest that the sources of the C16 n‐FA in the two forms are different, whereas both free and bound C28 n‐FA originate from terrestrial plants. The δD of combined (free plus bound) C28 n‐FA in the 200 m sediment core shows a large variability, with relatively low and high values during the glacial and interglacial periods, respectively. Based on comparison of our record with other marine and lacustrine paleoclimate data, we found that the sedimentary record of C28 n‐FA δD likely reflects the temperature‐induced change in δD of summer precipitation. This finding suggests that δD values of C28 n‐FA could be used as a proxy for summer paleotemperatures in the sediments of Lake Biwa and other lakes. Copyright © 2012 John Wiley & Sons, Ltd.
Equisetumarvense hydro‐alcoholic extract: phenolic composition and antifungal and antimycotoxigenic effect against Aspergillusflavus and Fusariumverticillioides in stored maize
Authors: Garcia Daiana , Ramos Antonio J. , Sanchis Vicente , Marín Sonia
Published: December 2012

Background

Maize is a very important cereal for human and animal diet, but it can be contaminated by moulds and their mycotoxins. On the other hand, natural plant products with antimicrobial properties could possibly used to control mycotoxigenic fungi in foods and feeds. In this study, Equisetum arvense extract was tested for the efficacy on Aspergillus section Flavi and Fusarium section Liseola growth. Natural contaminated maize was used in this study and extract was added under different water activities (aw) – 0.90 and 0.95 – for Aspergillus section Flavi and Fusarium section Liseola, respectively. Moulds were inoculated in maize and incubated during 30 days.

Results

We confirm that E. arvense extract may be effective for the inhibition of Aspergillus section Flavi in maize with high levels of this mould. Moreover, this extract showed a good inhibition of growth on Fusarium section Liseola levels. Aflatoxin and fumonisin production was not affected by the extract.

Conclusions

E. arvense extract could be an alternative to synthetic fungicides to control maize mycobiota level in moist grain. © 2013 Society of Chemical Industry
Pancreatic lipase–colipase binds strongly to the thylakoid membrane surface
Authors: Emek Sinan Cem , Åkerlund Hans‐Erik , Erlanson‐Albertsson Charlotte , Albertsson Per‐Åke
Published: December 2012

Background

Isolated thylakoid membranes, i.e. the photosynthetic membranes of green leaves, inhibit the activity of pancreatic lipase and colipase during hydrolysis of fat in vitro. This inhibition has been demonstrated to cause reduced food intake and improved hormonal and lipid profile in vivo. One of the reasons suggested for the inhibiting effect is binding of lipase–colipase to the thylakoid membrane surface. This prompted a study of the binding of lipase and colipase to thylakoids.

Results

The results showed that lipase and colipase strongly bind to the thylakoid membrane surface. The dissociation constant was determined at 1.2 × 10−8 mol L−1; binding decreased after treatment of thylakoids with pepsin/trypsin to 1.0 × 10−7 and to 0.6 × 10−7 mol L−1 after treatment with pancreatic juice. Similarly, delipidation of thylakoids caused a decrease in binding, the dissociation constant being 2.0 × 10−7 mol L−1.

Conclusion

The binding of pancreatic lipase–colipase to the thylakoid membrane is strong and may explain the inhibition of lipase–colipase activity by thylakoids. After treatment with proteases to mimic intestinal digestion binding is decreased, but is still high enough to explain the observed metabolic effects of thylakoids in vivo. © 2013 Society of Chemical Industry
Green ultra‐fast high‐performance liquid chromatographic method using a short narrow‐bore column packed with fully porous sub‐2 μm particles for the simultaneous determination of selected pharmaceuticals as surface water and wastewater pollutants
Authors: Shaaban Heba , Górecki Tadeusz
Published: December 2012

Fast separations are very desirable in laboratories that analyze large numbers of samples per day or those needing short turn‐around times. Traditional HPLC methods using conventional stationary phases and standard column dimensions require significant amounts of organic solvents and generate large volumes of waste. With growing awareness about the environment, the development of green technologies has been receiving increasing attention. In this work, a very fast green analytical method based on LC‐UV using a short narrow bore column packed with fully porous sub‐2 μm particles has been developed for simultaneous determination of nine pharmaceuticals in wastewater and surface water. The chromatographic separation was optimized in order to achieve short analysis time and good resolution for all analytes in a single run. All analytes could be separated in 1 min with good resolution. Sample preparation was executed by solid phase extraction using Oasis HLB cartridges. The method developed was validated based on parameters such as linearity, precision, accuracy, detection, and quantification limits. The recovery ranged from 70.9 to 92.5% with SDs not higher than 5.4%, except for acetaminophen and sulphanilamide. LODs ranged from 0.6–2.5 μg/L, while the LOQs were in the range 2–8 μg/L.
Dietary adjustability of grizzly bears and American black bears in Yellowstone National Park
Authors: Fortin Jennifer K. , Schwartz Charles C. , Gunther Kerry A. , Teisberg Justin E. , Haroldson Mark A. , Evans Marc A. , Robbins Charles T.
Published: December 2012

Grizzly bears (Ursus arctos) and American black bears (U. americanus) are sympatric in much of Yellowstone National Park. Three primary bear foods, cutthroat trout (Oncorhynchus clarki), whitebark pine (Pinus albicaulis) nuts, and elk (Cervus elaphus), have declined in recent years. Because park managers and the public are concerned about the impact created by reductions in these foods, we quantified bear diets to determine how bears living near Yellowstone Lake are adjusting. We estimated diets using: 1) stable isotope and mercury analyses of hair samples collected from captured bears and from hair collection sites established along cutthroat trout spawning streams and 2) visits to recent locations occupied by bears wearing Global Positioning System collars to identify signs of feeding behavior and to collect scats for macroscopic identification of residues. Approximately 45 ± 22% (${\bar {x}}$ ± SD) of the assimilated nitrogen consumed by male grizzly bears, 38 ± 20% by female grizzly bears, and 23 ± 7% by male and female black bears came from animal matter. These assimilated dietary proportions for female grizzly bears were the same as 10 years earlier in the Lake area and 30 years earlier in the Greater Yellowstone Ecosystem. However, the proportion of meat in the assimilated diet of male grizzly bears decreased over both time frames. The estimated biomass of cutthroat trout consumed by grizzly bears and black bears declined 70% and 95%, respectively, in the decade between 1997–2000 and 2007–2009. Grizzly bears killed an elk calf every 4.3 ± 2.7 days and black bears every 8.0 ± 4.0 days during June. Elk accounted for 84% of all ungulates consumed by both bear species. Whitebark pine nuts continue to be a primary food source for both grizzly bears and black bears when abundant, but are replaced by false‐truffles (Rhizopogon spp.) in the diets of female grizzly bears and black bears when nut crops are minimal. Thus, both grizzly bears and black bears continue to adjust to changing resources, with larger grizzly bears continuing to occupy a more carnivorous niche than the smaller, more herbivorous black bear. © 2012 The Wildlife Society.
Robust and Adhesive Hydrogels from Cross‐Linked Poly(ethylene glycol) and Silicate for Biomedical Use
Authors: Wu Chia‐Jung , Wilker Jonathan J. , Schmidt Gudrun
Published: December 2012

A systematic approach to develop robust and adhesive hydrogels by photopolymerizing poly(ethylene glycol) (PEG)‐diacrylate and methoxy‐PEG‐acrylate in the presence of charged silicate nanoparticles (Laponite) is presented. PEG‐diacrylate and silicate are used for covalent and physical cross‐linking, thus providing the hydrogel with mechanical and adhesive strengths. Methoxy‐PEG‐acrylate is used as a softening agent. The resulting hydrogels can be extensively elongated and the hydrogels readily adhere to tissue even in the elongated state. These hydrogels may aid the development of adhesive tissue engineering matrixes, wound dressings, sealants, and the adhesive components of biomedical devices.

magnified image
Utility of respiratory‐navigator‐rejected k‐space lines for improved signal‐to‐noise ratio in three‐dimensional cardiac MR
Authors: Akçakaya Mehmet , Shaw Jaime L. , Hauser Thomas H. , Nezafat Reza
Published: December 2012

Purpose

To develop and evaluate a technique that uses the k‐space lines rejected by prospective respiratory navigator (NAV) to improve the signal‐to‐noise ratio (SNR) without increasing the scan time.

Methods

In conventional image reconstruction, the motion‐corrupted k‐space lines rejected by the NAV are not used. In this study, a set of translational motion parameters for the NAV‐rejected lines and a phase‐corrected average for the k‐space line are estimated jointly using a maximum‐likelihood approach and the information from the corresponding accepted k‐space lines. Left coronary artery images were acquired in 10 healthy adult subjects, and the proposed approach incorporating the NAV‐rejected lines was compared with the conventional dataset with NAV‐accepted lines only, as well as a simple average of all k‐space lines, in terms of SNR, normalized vessel sharpness and qualitative image scores on a four‐point scale (1 = poor, 4 = excellent). Late gadolinium enhancement images of the left atrium were also acquired in 21 patients with atrial fibrillation pre‐ or post‐pulmonary vein isolation. Images reconstructed with the proposed, conventional, and simple averaging methods were compared in terms of SNR, and subjective image quality on a four‐point scale.

Results

For coronary MRI, there was a significant improvement in SNR with the proposed technique, but no significant difference in normalized vessel sharpness or qualitative image scores were observed with respect to the conventional method. Simple averaging resulted in an SNR gain, but significant loss in vessel sharpness and image quality. For late gadolinium enhancement, there was a significant increase in SNR, but no significant differences were observed in subjective image quality scores between the proposed and conventional methods. There was an SNR gain, but image quality loss for simple averaging, when compared with the conventional technique. In both coronary MRI and late gadolinium enhancement, the SNR gain of the proposed method was not significantly different than the maximum theoretical SNR gain.

Conclusion

The proposed technique improves SNR using the additional information from NAV‐rejected k‐space lines, while providing similar image quality to standard reconstruction using motion‐free k‐space data only, with no increase in scan time. Magn Reson Med 70:1332–1339, 2013. © 2012 Wiley Periodicals, Inc.
Voxel spread function method for correction of magnetic field inhomogeneity effects in quantitative gradient‐echo‐based MRI
Authors: Yablonskiy Dmitriy A. , Sukstanskii Alexander L. , Luo Jie , Wang Xiaoqi
Published: December 2012

Purpose

Macroscopic magnetic field inhomogeneities adversely affect different aspects of MRI images. In quantitative MRI when the goal is to quantify biological tissue parameters, they bias and often corrupt such measurements. The goal of this article is to develop a method for correction of macroscopic field inhomogeneities that can be applied to a variety of quantitative gradient‐echo‐based MRI techniques.

Methods

We have reanalyzed a basic theory of gradient echo MRI signal formation in the presence of background field inhomogeneities and derived equations that allow for correction of magnetic field inhomogeneity effects based on the phase and magnitude of gradient echo data. We verified our theory by mapping effective transverse relaxation rate in computer simulated, phantom, and in vivo human data collected with multigradient echo sequences.

Results

The proposed technique takes into account voxel spread function effects and allowed obtaining virtually free from artifacts effective transverse relaxation rate maps for all simulated, phantom and in vivo data except of the edge areas with very steep field gradients.

Conclusion

The voxel spread function method, allowing quantification of tissue specific effective transverse relaxation rate‐related tissue properties, has a potential to breed new MRI biomarkers serving as surrogates for tissue biological properties similar to longitudinal and transverse relaxation rate constants widely used in clinical and research MRI. Magn Reson Med 70:1283–1292, 2013. © 2012 Wiley Periodicals, Inc.
Holographic recording characteristics and physical mechanism of zinc methacrylate/nitroaniline‐co‐doped poly(methyl methacrylate)/9,10‐phenanthrenequinone photopolymers
Authors: Ko Cheng‐Jung , Chen Po‐Lin , Hsiao Yi‐Nan , Lin Shiuan‐Huei , Whang Wha‐Tzong , Hsu Ken Y. , Huang Kuo‐Jung , Chen Chun‐Chao , Tseng I‐Hsiang , Tsai Mei‐Hui
Published: December 2012

In this study we developed an approach to improve the characteristics of photopolymers for holographic data storage. Through codoping different compounds, N,N‐dimethyl‐4‐nitroaniline (DMNA) and zinc methylacrylate (Zn(MA)2), into 9,10‐phenanthrenequinone (PQ) doped poly(methyl methacrylate) (PMMA), the diffraction efficiency and the value of dynamic range (M#) have been progressed. We enhanced the diffraction efficiency (from 36.1 to 86.2%) and the dynamic range (M#, from 2.9 to 10.7) of PQ‐doped PMMA through codoping with DMNA and Zn(MA)2. Using mass spectrometry and X‐ray photoelectron spectroscopy, we investigated the mechanism behind the improvements in optical storage induced by the presence of Zn(MA)2 and DMNA in PMMA/PQ. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
A New Method to Determine the Upper Boundary Condition for a Permafrost Thermal Model: An Example from the Qinghai‐Tibet Plateau
Authors: Zhang Mingyi , Min Ki‐Hong , Wu Qingbai , Zhang Jianming , Harbor Jon
Published: December 2012

Assessing possible permafrost degradation related to engineering projects, climate change and land use change is of critical importance for protecting the environment and in developing sustainable designs for vital infrastructure in cold regions. A major challenge in modelling the future degradation of permafrost is finding ways to constrain changes in the upper thermal boundary condition over time and space at appropriate scales. Here, we report on an approach designed to predict time series of air, ground surface and shallow ground temperatures at a spatial scale on the order of 102 m2 for engineering design of a railway or highway project. The approach uses a regional‐scale atmospheric model to downscale global climate model output, and then stepwise multiple regression to develop an equation that provides a best‐fit prediction of site‐specific observational data using bilinearly interpolated output from the atmospheric model. This approach bridges the scale difference between atmospheric climate models and permafrost thermal models, and allows for a wider range of factors to be used in predicting the thermal boundary condition. For a research site located in Beiluhe, China, close to the Qinghai‐Tibet Railway, a comparison of model predictions with observational data not used in the construction of the model shows that this method can be used with a high degree of accuracy to determine the upper boundary condition for a permafrost thermal model. Once a model is constructed, it can be used to predict future changes in boundary condition parameters under different greenhouse emission scenarios for climate change. Copyright © 2012 John Wiley & Sons, Ltd.
Electrons on dislocations
Authors: Reiche Manfred , Kittler Martin , Krause Michael , Übensee Hartmut
Published: December 2012

The electrical behaviour of only a few dislocations was analysed. Such small numbers of defined dislocations were produced by hydrophobic semiconductor wafer direct bonding. The dislocation networks were placed in the channel of SOI MOSFETs where the source and drain regions of these devices act as contacts. Varying the channel width allows one to control the number of dislocations measured. Analyses of nMOSFETs proved an increase of the drain current caused by dislocations by more than one order of magnitude, while a decrease of the current is obtained for pMOSFETs. This indicates that electrons are present on the dislocation core in p‐type material. The concentration of electrons on dislocations was estimated to be about 200 electrons per micrometer dislocation length, corresponding to a distance of about 5 nm between free electrons. This distance agrees with the space between Coulomb islands proved by low‐temperature measurements. The investigations refer to a metallic‐like conductance along dislocations caused by a two‐dimensional carrier confinement. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultra‐High Optical Absorption Efficiency from the Ultraviolet to the Infrared Using Multi‐Walled Carbon Nanotube Ensembles
Authors: Kaul Anupama B. , Coles James B. , Eastwood Michael , Green Robert O. , Bandaru Prabhakar R.
Published: December 2012

The optical absorption efficiencies of vertically aligned multi‐walled (MW)‐carbon nanotube (CNT) ensembles are characterized in the 350−7000 nm wavelength range where CNT site densities > 1 × 1011/cm2 are achieved directly on metallic substrates. The site density directly impacts the optical absorption characteristics, and while high‐density arrays of CNTs on electrically insulating and non‐metallic substrates have been commonly reported, achieving high site‐densities on metals has been challenging and remains an area of active research. These absorber ensembles are ultra‐thin (<10 μm) and yet they still exhibit a reflectance as low as ∼0.02%, which is 100 times lower than the reference; these characteristics make them potentially attractive for high‐sensitivity and high‐speed thermal detectors. In addition, the use of a plasma‐enhanced chemical vapor deposition process for the synthesis of the absorbers increases the portfolio of materials that can be integrated with such absorbers due to the potential for reduced synthesis temperatures. The remarkable ruggedness of the absorbers is also demonstrated as they are exposed to high temperatures in an oxidizing ambient environment, making them well‐suited for extreme thermal environments encountered in the field, potentially for solar cell applications. Finally, a phenomenological model enables the determinatiom of the extinction coefficients in these nanostructures and the results compare well with experiment.
V1+xNb1–xIrB2 (x ≈ 0.1), The First Quaternary Metal‐Rich ­Boride Adopting The Mo2IrB2‐Type Structure: Synthesis, Crystal and Electronic Structure and Bonding Analysis
Authors: Goerens Christian , Fokwa Boniface P. T.
Published: December 2012

Polycrystalline samples and single crystals of the new metal‐rich boride V1+xNb1–xIrB2 (x ≈ 0.1), were synthesized by arc‐melting the elements in a water‐cooled copper crucible under an argon atmosphere and characterized by X‐ray diffraction and EDX measurements. The crystal structure was refined on the basis of single crystal data. The new phase adopts the Mo2IrB2‐type structure (space group Pnnm, no. 58) with the lattice parameters a = 7.301(7) Å, b = 9.388(9) Å and c = 3.206(5) Å. It is the first quaternary representative of Mo2IrB2‐type structure. The structure contains zigzag B4‐fragments with boron–boron distances of 1.83–1.85 Å. The electronic density of states and crystal orbital Hamilton population (for bonding analysis) were calculated, using the linear muffin‐tin orbital atomic sphere approximation (LMTO‐ASA) method. According to these calculations, this metal‐rich compound should be metallic, as expected. Furthermore, very strong boron–boron interactions are observed in the zigzag B4‐fragment and two significantly different Ir–B interactions are observed in the new phase and the prototype Mo2IrB2.
First Glimpses at Higgs’ face
Authors: Espinosa J. R. , Grojean C. , Mühlleitner M. , Trott M.
Published: December 2012

Abstract

The 8 TeV LHC Higgs search data just released indicates the existence of a scalar resonance with mass ~ 125 GeV. We examine the implications of the data reported by ATLAS, CMS and the Tevatron collaborations on understanding the properties of this scalar by performing joint fits on its couplings to other Standard Model (SM) particles. We discuss and characterize to what degree this resonance has the properties of the SM Higgs, and consider what implications can be extracted for New Physics in a (mostly) model-independent fashion. We find that, if the Higgs couplings to fermions and weak vector bosons are allowed to differ from their standard values, the SM is ~ 2σ from the best fit point to the current data. Fitting to a possible invisible decay branching ratio, we find BRinv ≃ 0.05 ± 0.32 (95% C.L.). We also discuss and develop some ways of using the data in order to bound or rule out models which modify significantly the properties of this scalar resonance, and apply these techniques to the current global dataset.
The Carnegie Curve
Authors: Harrison R. Giles
Published: December 2012

The Earth’s fair weather atmospheric electric field shows, in clean air, an average daily variation which follows universal time, globally independent of the measurement position. This single diurnal cycle variation (maximum around 19UT and minimum around 03UT) is widely known as the Carnegie curve, after the geophysical survey vessel of the Carnegie Institution of Washington on which the original measurement campaigns demonstrating the universal time variation were undertaken. The Carnegie curve’s enduring importance is in providing a reference variation against which atmospheric electricity measurements are still compared; it is believed to originate from regular daily variations in atmospheric electrification associated with the different global disturbed weather regions. Details of the instrumentation, measurement principles and data obtained on the Carnegie’s seventh and final cruise are reviewed here, also deriving new harmonic coefficients allowing calculation of the Carnegie curve for different seasons. The additional harmonic analysis now identifies changes in the phasing of the maximum and minimum in the Carnegie curve, which shows a systematic seasonal variation, linked to the solstices and equinoxes, respectively.
Ethical Issues in Presymptomatic Genetic Testing for Minors: A dilemma in Li‐Fraumeni Syndrome
Authors: Fresneau Brice , Brugières Laurence , Caron Olivier , Moutel Grégoire
Published: December 2012

In 2001, a French expert panel recommended that presymptomatic tests should not be carried out on minors in families affected by Li‐Fraumeni syndrome (LFS), flying in the face of possible parental demands for such testing. We decided to investigate the legitimacy of such a recommendation. We conducted a national multicenter survey using self‐administered questionnaires mailed to French oncogeneticists in 33 regional centers in France. We aimed to (1) determine the extent to which these doctors were confronted with parental requests for TP53 testing, (2) study how they responded to these requests and the arguments used and (3) assess the attitude of oncogeneticists concerning the normative framework regulating the prescription of tests for minors. Twenty oncogeneticists stated that they had managed at least one LFS family. Eleven of these doctors had been confronted with parental requests for testing and three had prescribed such tests on at least one occasion. The oncogeneticists gave balanced medical, psychological and ethical arguments, highlighting the dilemma they face in the decision‐making process. This dilemma is due to the lack of a consensus concerning this recommendation, which aims to protect the minor by limiting presymptomatic tests to cases in which a clear medical benefit can be demonstrated but which prevents the unique situation of particular families from being taken into account. In conclusion, the recommendation has a normative status but first, from a clinical stance, it is difficult to dissociate it from the evaluation of individual family situations, and second, the benefit of a specific medical follow‐up for TP53 mutation carriers is currently being investigated.
Assessing road effects on bats: the role of landscape, road features, and bat activity on road‐kills
Authors: Medinas Denis , Marques J. Tiago , Mira António
Published: December 2012

Recent studies suggest that roads can significantly impact bat populations. Though bats are one of the most threatened groups of European vertebrates, studies aiming to quantify bat mortality and determine the main factors driving it remain scarce. Between March 16 and October 31 of 2009, we surveyed road‐killed bats daily along a 51‐km‐long transect that incorporates different types of roads in southern Portugal. We found 154 road‐killed bats of 11 species. The two most common species in the study area, Pipistrellus kuhlii and P. pygmaeus, were also the most commonly identified road‐kill, representing 72 % of the total specimens collected. About two‐thirds of the total mortality occurred between mid July and late September, peaking in the second half of August. We also recorded casualties of threatened and rare species, including Miniopterus schreibersii, Rhinolophus ferrumequinum, R. hipposideros, Barbastella barbastellus, and Nyctalus leisleri. These species were found mostly in early autumn, corresponding to the mating and swarming periods. Landscape features were the most important variable subset for explaining bat casualties. Road stretches crossing or in the vicinity of high‐quality habitats for bats—including dense Mediterranean woodland (“montado”) areas, water courses with riparian gallery, and water reservoirs—yielded a significantly higher number of casualties. Additionally, more road‐killed bats were recorded on high‐traffic road stretches with viaducts, in areas of higher bat activity and near known roosts.
Economic Development
Authors: Nafziger E. Wayne
Published: December 2012

Nafziger explains the reasons for the recent fast growth of India, Poland, Brazil, China, and other Pacific Rim countries, and the slow, yet essential, growth for a turnaround of sub-Saharan Africa. The book is suitable for those with a background in economics principles. The fifth edition of the text, written by a scholar of developing countries, is replete with real-world examples and up-to-date information. Nafziger discusses poverty, income inequality, hunger, unemployment, the environment and carbon-dioxide emissions, and the widening gap between rich (including middle-income) and poor countries. Other new components include the rise and fall of models based on Russia, Japan, China/Taiwan/Korea and North America; randomized experiments to assess aid; an exploration of whether information technology and mobile phones can provide poor countries with a shortcut to prosperity; and a discussion of how worldwide financial crises, debt, and trade and capital markets affect developing countries.
The Fern Garden
Authors: Hibberd Shirley
Published: December 2012

James Shirley Hibberd (1825–90) was a journalist and writer on gardening, whose popular works had great influence on middle-class taste. Although not a trained horticulturalist, his many books were based on practical experience. He developed a succession of gardens in north London concentrating on particular types of plants, and his books reflected this work, with the Rose Book (1864) and the Fern Garden (1869) being particularly successful. He also wrote on garden design, flower arrangement, garden furniture and architecture, and his Rustic Adornments of 1856, also published in this series, is an important work of social and fashion history. He edited the magazine Floral World until 1875 and later the Gardener's Magazine, and was even consulted by the government about potato blight. His engaging and very personal style made him a popular forerunner of modern celebrity gardeners, and set a fashion for highly decorative and ornamental gardens.
Linnaeus
Authors: Fries Theodor Magnus
Published: December 2012

This biography of Swedish botanist Carl Linnaeus (1707–78) was originally published in 1903 by another Swedish botanist, Theodor Magnus Fries (1832–1913). This English version, published in 1923, was translated and edited by British botanist Benjamin Daydon Jackson (1846–1927). Jackson is best known for founding (with J. D. Hooker) the Index Kewensis, the register of all botanical names of seed plants; he also acted as Secretary of the Linnean Society for twenty-two years, becoming its General Secretary in 1902. This biography covers the early life of Linnaeus (including some family history), his student years at Uppsala, his travels, his years as a teacher, notes on his personality and his relationship with the wider scientific community. Jackson provides further information in the appendices, enhancing Fries' work with Linnaeus' genealogy, a list of his pupils, his private notes on 'Divine Punishment' and a brief history of Sweden during Linnaeus' lifetime.
Paxton's Flower Garden
Authors: Paxton Joseph , Lindley John
Published: December 2012

Best remembered today for his technically innovative design for the Crystal Palace of 1851, Joseph Paxton (1803–65) was head gardener to the Duke of Devonshire at Chatsworth by the age of twenty-three, and remained involved in gardening throughout his life. Tapping in to the burgeoning interest in gardening amongst the Victorians, in 1841 he founded the periodical The Gardener's Chronicle with the botanist John Lindley (1799–1865), with whom he had worked on a Government report on Kew Gardens. Paxton's Flower Garden appeared between 1850 and 1853, following a series of plant-collecting expeditions. Only three of the planned ten volumes were published, but with hand-coloured plates (which can be viewed online alongside this reissue) and over 500 woodcuts, the work is lavish. Further colour plates of orchids are to be found in Volume 2, clearly a reflection of Lindley's interest, but also of the wider fascination for these flowers.