bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of predictive hydrological uncertainty using quantile regression: examples from the National Flood Forecasting System (England and Wales)
Authors: Weerts A. H. , Winsemius H. C. , Verkade J. S.
Published: January 2011

Abstract. In this paper, a technique is presented for assessing the predictive uncertainty of rainfall-runoff and hydraulic forecasts. The technique conditions forecast uncertainty on the forecasted value itself, based on retrospective Quantile Regression of hindcasted water level forecasts and forecast errors. To test the robustness of the method, a number of retrospective forecasts for different catchments across England and Wales having different size and hydrological characteristics have been used to derive in a probabilistic sense the relation between simulated values of water levels and matching errors. From this study, we can conclude that using Quantile Regression for estimating forecast errors conditional on the forecasted water levels provides a relatively simple, efficient and robust means for estimation of predictive uncertainty.
Multifractal analysis of oceanic chlorophyll maps remotely sensed from space
Authors: de Montera L. , Jouini M. , Verrier S. , Thiria S. , Crepon M.
Published: January 2011

Abstract. Phytoplankton patchiness has been investigated with multifractal analysis techniques. We analyzed oceanic chlorophyll maps, measured by the SeaWiFS orbiting sensor, which are considered to be good proxies for phytoplankton. Multifractal properties are observed, from the sub-mesoscale up to the mesoscale, and are found to be consistent with the Corssin-Obukhov scale law of passive scalars. This result indicates that, within this scale range, turbulent mixing would be the dominant effect leading to the observed variability of phytoplankton fields. Finally, it is shown that multifractal patchiness can be responsible for significant biases in the nonlinear source and sink terms involved in biogeochemical numerical models.
Nanomechanical Properties of Oligo(ethylene glycol methacrylate) Polymer Brush‐Based Biointerfaces
Authors: Tranchida Davide , Sperotto Elena , Staedler Thorsten , Jiang Xin , Schönherr Holger
Published: January 2011

Protein resistant polymer brushes of poly(diethylene glycol methylether methacrylate) (DEGMA) are synthesized by surface‐initiated polymerization (SIP) on gold and are thoroughly characterized with particular attention to the nanomechanical properties. Compared to the well known brushes of poly(oligoethylene glycol methylether methacrylate) (POEGMA) on gold, PDEGMA brushes grow faster and yield higher final brush heights. In confocal fluorescence microscopy experiments it is shown that both types of brushes possess similar low non‐specific adsorption levels of labeled bovine serum albumin (BSA) from buffer. While the surface stiffness evaluated by depth sensing indentation in the dry state suggests that side chain crystallization imparts high stiffness to the POEGMA brush, PDEGMA brushes behave similar to poly(methyl methacrylate) (PMMA) brushes of comparable thickness. In the wet state PDEGMA brushes are shown to possess an elastic modulus of 800 kPa, as estimated by AFM nanoindentation, which is smaller than that of POEGMA (3 000 kPa). Expanding these brushes to end‐functional polymers with recently developed block copolymer brush approaches, tailored soft biointerfaces can be generated for cell ‐ surface interaction and cell culture studies.
The Tn Antigen—Structural Simplicity and Biological Complexity
Authors: Ju Tongzhong , Otto Vivianne I. , Cummings Richard D.
Published: January 2011

Glycoproteins in animal cells contain a variety of glycan structures that are added co‐ and/or posttranslationally to proteins. Of over 20 different types of sugar–amino acid linkages known, the two major types are N‐glycans (Asn‐linked) and O‐glycans (Ser/Thr‐linked). An abnormal mucin‐type O‐glycan whose expression is associated with cancer and several human disorders is the Tn antigen. It has a relatively simple structure composed of N‐acetyl‐D‐galactosamine with a glycosidic α linkage to serine/threonine residues in glycoproteins (GalNAcα1‐O‐Ser/Thr), and was one of the first glycoconjugates to be chemically synthesized. The Tn antigen is normally modified by a specific galactosyltransferase (T‐synthase) in the Golgi apparatus of cells. Expression of active T‐synthase is uniquely dependent on the molecular chaperone Cosmc, which is encoded by a gene on the X chromosome. Expression of the Tn antigen can arise as a consequence of mutations in the genes for T‐synthase or Cosmc, or genes affecting other steps of O‐glycosylation pathways. Because of the association of the Tn antigen with disease, there is much interest in the development of Tn‐based vaccines and other therapeutic approaches based on Tn expression.
Influence of life‐history variation on demographic responses of three freshwater mussel species (Bivalvia: Unionidae) in the Clinch River, USA
Authors: Jones Jess W. , Neves Richard J.
Published: January 2011

Variation in age, shell growth, and demographic responses of two endangered mussel species, Epioblasma brevidens and Epioblasma capsaeformis, and a third non‐listed species, Lampsilis fasciola, were studied from 2004–2008 in a 32‐km reach of the Clinch River, TN.

Observed maximum age and length of E. brevidens was 28 yr and 71.5 mm for males and 15 yr and 56.6 mm for females; of E. capsaeformis, 12 yr and 54.6 mm for males and 9 yr and 48.6 mm for females; and of L. fasciola, 45 yr and 91.3 mm for males and 24 yr and 79.8 mm for females.

Estimated population size was ∼46 000 individuals for E. brevidens, ∼862 000 individuals for E. capsaeformis, and ∼33 000 individuals for L. fasciola.

Mean recruitment per year of 1 yr‐olds ranged from 12.0% to 24.0% for E. brevidens, 4.2% to 56.6% for E. capsaeformis, and 10.0% to 38.5% for L. fasciola, and mean annual population growth rate was 21.0%, 31.3%, and − 24.3%, respectively.

Juveniles were detectable but temporally and spatially variable in occurrence, and a significant proportion of the age‐class structure of each species. Recruitment was exceptionally high for E. capsaeformis during years when discharge was low in spring and summer.

Population size, growth, recruitment, and mortality rates of the shorter‐lived E. capsaeformis were correspondingly higher than those of E. brevidens and L. fasciola.

The federal recovery plan for E. brevidens and E. capsaeformis identifies quantification of demographic variables as a critical step toward meeting the recovery needs of each species. The data collected in this study begin to meet these needs and can be used to monitor and evaluate population performance of each species. Published in 2011 by John Wiley & Sons, Ltd.
Logistic model of injury risks in single vehicle crashes in urban neighborhoods
Authors: Rifaat Shakil Mohammad , Tay Richard , de Barros Alexandre G.
Published: January 2011

Road crashes not only claim lives but also impose an economic burden on society due to loss of productivity. Researchers are continuously developing crash models to get a better understanding of the factors affecting crash occurrences and severity. The objective of this study is to explore the influence of neighborhood characteristics on crash injury using the City of Calgary as a case study. A logistic model is estimated using the data for single vehicle crashes for the years 2003–2005. Our results show that limited access street patterns are safer than the traditional grid‐iron pattern but the effect is not significant. Copyright © 2011 John Wiley & Sons, Ltd.
Another place, another timer: Marine species and the rhythms of life
Authors: Tessmar‐Raible Kristin , Raible Florian , Arboleda Enrique
Published: January 2011

The marine ecosystem is governed by a multitude of environmental cycles, all of which are linked to the periodical recurrence of the sun or the moon. In accordance with these cycles, marine species exhibit a variety of biological rhythms, ranging from circadian and circatidal rhythms to circalunar and seasonal rhythms. However, our current molecular understanding of biological rhythms and clocks is largely restricted to solar‐controlled circadian and seasonal rhythms in land model species. Here, we discuss the first molecular data emerging for circalunar and circatidal rhythms and present selected species suitable for further molecular analyses. We argue that a re‐focus on marine species will be crucial to understand the principles, interactions and evolution of rhythms that govern a broad range of eukaryotes, including ourselves.
Single‐chain antibody fragment production in Pichia pastoris: Benefits of prolonged pre‐induction glycerol feeding
Authors: Khatri Narendar K. , Gocke Dörte , Trentmann Oliver , Neubauer Peter , Hoffmann Frank
Published: January 2011

Secretory production of a single‐chain antibody fragment (scFv) by recombinant Pichia pastoris using the methanol inducible AOX1 promoter is limited biochemically by retarded secretion, and economically by the high demand for pure oxygen. To address the problem, the adaptation phase with growth‐limiting feeding of glycerol before the production phase was optimized. In a standard procedure with a short glycerol‐feeding phase before induction, scFv accumulated in the supernatant only after 15 h. Conversely, scFv started to appear immediately in the medium upon methanol induction when the glycerol‐feeding phase was extended to 18 h. Interestingly, despite a significantly lower cell density in the cultivation with extended glycerol feeding, the same amount of functional product of 300 mg/L was obtained about 30 h after the start of glycerol feeding with both methods. mRNA analysis revealed that the higher and faster production of the product was related to longer lasting induction of the scFv mRNA. Additional effects of a better adaptation of the secretion machinery may be suggested by higher expression of unfolded protein response‐related genes KAR2 and PDI. A clear benefit of the longer glycerol‐feeding phase was a 75% reduction of the consumption of both pure oxygen and methanol, and a significantly lower cell density, which would be beneficial for down‐stream purification of the product.
Chromophore Exchange in the Blue Light‐Sensitive Photoreceptor YtvA from Bacillus subtilis
Authors: Mansurova Madina , Scheercousse Pierre , Simon Julian , Kluth Marianne , Gärtner Wolfgang
Published: January 2011

YtvA from Bacillus subtilis was found as the first prokaryotic phototropin‐like blue‐light‐responsive photoreceptor. It is composed of two domains, the photoactive LOV (light, oxygen, voltage) domain, which binds a flavin mononucleotide (FMN) as a chromophore and a STAS (sulfate transporter/anti‐sigma‐factor antagonist) domain, which generates a physiological signal. Here we present a routine chromophore‐exchange protocol that allows chemically synthesized, structurally modified chromophores instead of the naturally present flavin mononucleotide (FMN) chromophore to be introduced. FMN was exchanged for riboflavin (RF), flavin adenine dinucleotide (FAD), 7,8‐didemethyl flavin mononucleotide (DMFMN), and 8‐isopropyl flavin mononucleotide (iprFMN). LOV domains reconstituted with new flavins undergo the same photocycle as native YtvA LOV, consisting of triplet formation and covalent binding of the chromophore followed by a thermal recovery of the parent state, albeit with different kinetics and photophysical properties. Interestingly, the iprFMN chromophore, inducing steric hindrances to the protein, exhibits a very fast light‐to‐dark‐conversion and shows a high fluorescence quantum yield (0.4). Incorporation of FAD causes an increase of its fluorescence quantum yield from 0.04 (H2O) to 0.2.
Left Ventricular Contraction Patterns in Patients With Suspected Acute Coronary Syndrome and Normal Coronary Angiograms: A New Look at the Takotsubo Syndrome
Authors: Paixao Andre R.M. , Balaji Nicholas , Ryzhikov Alex , Ghafourian Kambiz , Collins Sara , Suddath William O. , Satler Lowell F. , Kent Kenneth M. , Pichard Augusto D. , Waksman Ron , Lindsay Joseph
Published: January 2011

Background

Original descriptions of the takotsubo syndrome (TS) included a characteristic left ventricular (LV) contraction pattern, “apical ballooning.” Recently, several reports have associated contraction patterns not strictly conforming to the original description with TS. The specifics of the contraction pattern seem to set TS apart from the much larger population of patients with acute coronary syndrome (ACS) but no obstructive coronary artery disease (OCAD). This study was undertaken to compare patients with midventricular and apical dysfunction with those with other LV contraction patterns.

Hypothesis

If TS can present with a variety of patterns of LV dysfunction, then both those with and those without the pattern should have the clinical components previously assigned to the syndrome.

Methods

We studied LV contraction patterns in consecutive ACS patients referred for consideration of emergent or urgent percutaneous coronary intervention.

Results

Of the 893 patients evaluated in 2008, we excluded 862 on the basis of OCAD, preexisting LV dysfunction, or an obvious alternative cause of symptoms. The remaining 31 (3.5%) also had no OCAD but manifested an LV contraction abnormality. We compared the 15 patients (1.7%) whose ventriculograms met criteria for TS with the 16 patients (1.8%) whose did not. The most common alternative pattern was global hypokinesis, followed by a variety of segmental contraction abnormalities. Patients with the TS pattern were older and had evidence of greater myocardial injury. More than 85% were women.

Conclusions

The TS pattern identifies a distinct subset of ACS patients with a remarkable predominance of postmenopausal women and is therefore fundamental to the definition of this entity. This distinctive facet of the syndrome is likely to be an important clue to its pathogenesis. We did not encounter patients with other patterns of LV dysfunction that could be thought to represent stress‐induced cardiomyopathy. Copyright © 2011 Wiley Periodicals, Inc.

The authors have no funding, ﬁnancial relationships, or conﬂicts of interest to disclose.
Effect of Atenolol vs Metoprolol Succinate on Vascular Function in Patients With Hypertension
Authors: Heffernan Kevin S. , Suryadevara Ramya , Patvardhan Eshan A. , Mooney Paula , Karas Richard H. , Kuvin Jeffrey T.
Published: January 2011

Background

We evaluated the effect of atenolol vs metoprolol succinate on vascular function in patients with essential hypertension.

Hypothesis

Given intrinsic differences between these agents, we hypothesized that atenolol and metoprolol succinate would have disparate effects on vascular function.

Methods

This study included 24 patients with hypertension (age 56 ± 2 years, 8 female, body mass index 28 ± 1) and featured a randomized, double‐blind, crossover design. Each β‐blocker (atenolol or metoprolol succinate) was taken by patients once daily for a 4‐week period. Measures of vascular function included peripheral augmentation index (AIx) and pulse wave amplitude reactive hyperemia index from peripheral arterial tonometry, and brachial artery flow‐mediated dilation from ultrasound.

Results

There were similar reductions in mean arterial pressure following treatment with atenolol and metoprolol succinate. Compared with metoprolol succinate, there was a significant increase in peripheral AIx following atenolol therapy (P < 0.05). There were no changes in brachial artery flow‐mediated dilation or pulse wave amplitude reactive hyperemia index following either drug treatment.

Conclusions

Although atenolol and metoprolol succinate have similar effects on blood‐pressure reduction, they have different effects on vascular function. Compared with metoprolol succinate, atenolol increases peripheral AIx. Neither drug has an effect on vascular endothelial function. These findings may have clinical implications, depending on the indication for treatment in an individual patient. Copyright © 2011 Wiley Periodicals, Inc.

These data are derived from a parent study which was funded, in part, by AstraZeneca, Inc. K. Heffernan was supported by funding from NIH T32 HL069770‐06. The authors have no other funding, financial relationships, or conflicts of interest to disclose.
1‐(3‐Biaryloxy‐2‐oxopropyl)indole‐5‐carboxylic Acids and Related Compounds as Dual Inhibitors of Human Cytosolic Phospholipase A2α and Fatty Acid Amide Hydrolase
Authors: Zahov Stefan , Drews Andreas , Hess Mark , Schulze Elfringhoff Alwine , Lehr Matthias
Published: January 2011

Cytosolic phospholipase A2α (cPLA2α) and fatty acid amide hydrolase (FAAH) are enzymes that have emerged as attractive targets for the development of analgesic and anti‐inflammatory drugs. We recently reported that 1‐[3‐(4‐octylphenoxy)‐2‐ oxopropyl]indole‐5‐carboxylic acid (5) is a dual inhibitor of cPLA2α and FAAH. Structure–activity relationship studies revealed that substituents at the indole 3‐ and 5‐positions and replacement of the indole scaffold of this compound by other heterocycles strongly influences the inhibitory potency against cPLA2α and FAAH, respectively. Herein we report the effect of variation of the 4‐octyl residue of 5 and an exchange of its carboxylic acid moiety by some bioisosteric functional groups. Several of the compounds assayed were favorably active against both enzymes, and could therefore represent agents with improved analgesic and anti‐inflammatory qualities in comparison with selective cPLA2α and FAAH inhibitors.
Synthesis and characterization of manganese sulphide thin films deposited by spray pyrolysis
Authors: Chowdhury M. R. I. , Podder J. , Islam A. B. M. O.
Published: January 2011

Manganese sulphide (MnS) thin films have been deposited onto glass substrate by a low cost spray‐pyrolysis technique at 220 °C. The as‐deposited MnS thin films have been characterized using scanning electron microscopy (SEM), energy dispersive X‐ray (EDX) spectroscopy, atomic force microscopy (AFM), X‐ray diffraction, UV visible spectroscopy and photo electrochemical (PEC) measurement. The SEM and AFM images showed that the MnS thin films were well covered onto the substrate surface. The as‐deposited raw thin film was found to be amorphous in nature and perfectly crystalline phase after annealing the sample. Optical band gap of the MnS thin films was found to vary from 3.1 to 3.21 eV and the band gap decreases with the increase in film thickness. Optical constants such as refractive index, extinction coefficient have been evaluated using reflectance and absorbance data. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and characterization of simonkolleite nanodisks and their conversion into ZnO nanostructures
Authors: Li Yan , Zou Yunling , Hou Yanyan
Published: January 2011

Simonkolleite (Zn5(OH)8Cl2·2H2O) nanodisks with a width of 40 nm have been successfully synthesized via a hydrothermal method using zinc chloride and ammonia as the starting materials. The conversion mechanisms from simonkolleite nanodisks to ZnO spindles under hydrothermal condition and to ZnO nanotablets under solid phase transformation were discussed respectively. The simonkolleite nanodisks obviously occur in hydrothermal system with the combination of a lower alkalinity, lower temperature (<363 K), a higher NH4+ ions concentration and in existence of Cl‐ anion. The morphologies, crystal phases and photoluminescence properties of as‐synthesized samples were investigated by field emission scanning electron microscopy, powder X‐ray diffractometer and fluorescence spectrophotometer. The photocatalytic activities of these as‐synthesized samples in the degradation of methyl orange have been demonstrated. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compact Metal–Organic Frameworks for Anti‐Corrosion Applications: New Binary Linear Saturated Carboxylates of Zinc
Authors: Mesbah Adel , Jacques Sophie , Rocca Emmanuel , François Michel , Steinmetz Jean
Published: January 2011

Zinc‐based metal–organic frameworks (MOFs), binary zinc carboxylates ZnCnCn′ with Cn and Cn′ = CH3(CH2)n – 2COO–, have been synthesised and characterised for anti‐corrosion applications. The crystallographic structures of ZnC10C14 and ZnC10C16 were determied from synchrotron powder diffraction data and refined by the Rietveld method. Protective coatings on electrogalvanised steel composed of ZnC12C16 have been developed by formulating a particular “carboxylating” bath. The ZnC12C16 coating exhibits better anti‐corrosion behaviour than the pure Zn(C16)2 and Zn(C12)2 coatings, according to electrochemical and non‐electrochemical measurements. The crystallographic results and corrosion measurements demonstrate the great flexibility of the zinc carboxylate lamellar structures in modifying the insolubility and hydrophobicity of the protective coatings. In addition, the conditions for the ZnC12C16 coating process fulfil the specifications for the surface treatment of zinc. Finally, these new compounds, which can be easily synthesised in water, provide a new and environmentally friendly anti‐corrosion treatment for metals.
Predictability of saccadic behaviors is modified by transcranial magnetic stimulation over human posterior parietal cortex
Authors: Chao Chang‐Mao , Tseng Philip , Hsu Tzu‐Yu , Su Jia‐Han , Tzeng Ovid J.L. , Hung Daisy L. , Muggleton Neil G. , Juan Chi‐Hung
Published: January 2011

Predictability in the visual environment provides a powerful cue for efficient processing of scenes and objects. Recently, studies have suggested that the directionality and magnitude of saccade curvature can be informative as to how the visual system processes predictive information. The present study investigated the role of the right posterior parietal cortex (rPPC) in shaping saccade curvatures in the context of predictive and non‐predictive visual cues. We used an orienting paradigm that incorporated manipulation of target location predictability and delivered transcranial magnetic stimulation (TMS) over rPPC. Participants were presented with either an informative or uninformative cue to upcoming target locations. Our results showed that rPPC TMS generally increased saccade latency and saccade error rates. Intriguingly, rPPC TMS increased curvatures away from the distractor only when the target location was unpredictable and decreased saccadic errors towards the distractor. These effects on curvature and accuracy were not present when the target location was predictable. These results dissociate the strong contingency between saccade latency and saccade curvature and also indicate that rPPC plays an important role in allocating and suppressing attention to distractors when the target demands visual disambiguation. Furthermore, the present study suggests that, like the frontal eye fields, rPPC is critically involved in determining saccade curvature and the generation of saccadic behaviors under conditions of differing target predictability. Hum Brain Mapp, 2011. © 2011 Wiley‐Liss, Inc.
Genetic variation of the α2b‐adrenoceptor affects neural correlates of successful emotional memory formation
Authors: Urner Maren , van Wingen Guido , Franke Barbara , Rijpkema Mark , Fernández Guillén , Tendolkar Indira
Published: January 2011

Objective: Enhanced memory for emotionally charged events helps us to remember potentially vital information. There are large interindividual differences in emotional‐memory enhancement, but little is known about their neurobiological basis. Recently, a functional deletion variant of the gene that codes for the α2b‐adrenoceptor (ADRA2B) has been shown to affect memory for emotional experiences. Initial neuroimaging evidence linked this behavioral effect to increased amygdala activity, but its influence on successful memory processing remains unknown. Therefore, the aim of this study was to investigate the effect of the common deletion in the ADRA2B gene on neural activity related to specific mnemonic processing, successful memory formation, and retrieval. Methods: Twenty‐three noncarriers (10 males) and 28 deletion carriers (13 males) with a mean age of 24 years were investigated while performing an emotional‐learning task with sad and happy scenes. Functional magnetic resonance imaging was acquired both during memory formation and retrieval. Results: Although there were no differences in memory performance between groups, the common deletion variant of ADRA2B was related to enhanced activity in the amygdala and inferior frontal gyrus during successful emotional memory formation, but not retrieval. Deletion carriers showed a larger differential response in these brain regions between later‐remembered and later‐forgotten stimuli than nondeletion carriers did. Conclusion: Our results demonstrate that the ADRA2B polymorphism influences emotional memory formation but not memory retrieval in the amygdala and left inferior frontal gyrus. Hum Brain Mapp, 2011. © 2011 Wiley Periodicals, Inc.
N‐(2‐hydroxyaryl)benzamide synthesis from 2‐nitroaryl benzoates via an indium‐mediated reduction‐migration reaction
Authors: Lee Hyejeong , Kim Minki , Jun Young Moo , Kim Byeong Hyo , Lee Byung Min
Published: January 2011

A one‐pot reduction‐triggered N‐(2‐hydroxyaryl)benzamide synthesis from 2‐nitroaryl benzoate substrates was investigated. In the presence of indium/AcOH in THF/H2O, 2‐nitroaryl benzoates produced reasonable yields of the benzo group migrated N‐(2‐hydroxyaryl)benzamides at room temperature within 1 h. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:158–167, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20669
The reaction of red phosphorus with 1‐bromonaphthalene in the KOH–DMSO system: Synthesis of tri(1‐naphthyl)phosphane
Authors: Kuimov Vladimir A. , Malysheva Svetlana F. , Gusarova Nina K. , Vakul'skaya Tamara I. , Khutsishvili Spartak S. , Trofimov Boris A.
Published: January 2011

Red phosphorus reacts with 1‐bromonaphthalene in the KOH–DMSO system upon heating (47–70°C, 3 h) to give tri(1‐naphthyl)phosphane in 10% yield. Microwave activation (600 W, 6 min) of the reaction affords the above‐mentioned phosphane in 25% yield. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:198–203, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20671
New Phenylphenalene Derivatives from Water Hyacinth (Eichhornia crassipes)
Authors: Wang Ming‐Zhong , Cai Xiang‐Hai , Luo Xiao‐Dong
Published: January 2011

Water hyacinth (Eichhornia crassipes) is a cause of great concern in terms of environmental and agricultural impacts in many parts of the world. Phytochemical investigation of water hyacinth led to the isolation of six new phenylphenalenes, 2,3‐dihydro‐3,9‐dihydroxy‐5‐methoxy‐4‐phenyl‐1H‐phenalen‐1‐one (1), 2,3‐dihydro‐8‐methoxy‐9‐phenyl‐1H‐phenalene‐1,4‐diol (2), 2,3‐dihydro‐4,8‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐ol (3), 2,3‐dihydro‐9‐(4‐hydroxyphenyl)‐8‐methoxy‐1H‐phenalene‐1,4‐diol (4), 2,6‐dimethoxy‐9‐phenyl‐1H‐phenalen‐1‐one (5), and 7‐(4‐hydroxyphenyl)‐5,6‐dimethoxy‐1H‐phenalen‐1‐one (6), together with the four known compounds 7–10. Their structures were elucidated by spectrometric methods including 1D‐ and 2D‐NMR, and MS analysis. These compounds may be involved in allelopathic interactions of water hyacinth with neighboring plants.
A New Synthesis of Fused Oxa‐ and Thiacrown Ethers–Thiophene/Furan Oligomers
Authors: Garzino Frédéric , Méou Alain , Brun Pierre
Published: January 2011

We have developed a two‐step sequence for preparing a series of macrocyclic oxa‐ and thiacrown ethers affixed to a thiophene/furan oligomer. The sequence involves the intramolecular MnIII‐promoted cyclization of linear diester precursors into 2,3‐dihydrofurans, whose dehydrogenation furnishes the title compounds. A preliminary NMR study has shown that one of them seems to specifically chelate Pb2+ cations.
Synthesis of Diheteroarylamine Ligands by Palladium‐Catalyzed Mono‐ and Diamination of Dichlorohetero­arenes with Heteroarenamines
Authors: Samson Daniel , Daltrozzo Ewald
Published: January 2011

The syntheses of bidentate (see 6 and 12), bis‐bidentate (7, 10, and 13) up to oligo‐bidentate (see 11 and 14) diheteroarylamine‐based N,N‐ligands are reported (Tables 2, 4, and 5). In the course of investigations on heteroaromatic (CN)‐bond formations, a protocol for the Pd‐catalyzed mono‐ and diamination of 2,6‐dichloropyridine (1) and 4,6‐dichloropyrimidines 5 with heteroaren‐2‐amines 2 and pyrimidine‐4,6‐diamines 8 is developed. The results are applied to the syntheses of the ‘pentamers’ 11a–11d and the ‘heptamer’ 14 based on 4,6‐disubstituted 2‐alkylpyrimidines 5 and 8, respectively.
Eremophilenolide‐Type Sesquiterpenes from Hertia intermedia
Authors: Malik Abdul , Afza Nighat , Yasmeen Shazia , Aijaz Anwer Mohammad , Irfan Ali Muhammad , Bakhsh Tareen Rasool
Published: January 2011

Hertidins A–E (1–5, resp.), new eremophilenolide‐type sesquiterpenes, have been isolated from the AcOEt‐soluble fraction of Hertia intermedia. Structures of 1–5 were elucidated on the basis of extensive spectroscopic studies.
Preparation of the β2‐Homoselenocysteine Derivatives Fmoc‐(S)‐β2hSec(PMB)‐OH and Boc‐(S)‐β2hSec(PMB)‐OH for Solution and Solid‐Phase Peptide Synthesis
Authors: Patora‐Komisarska Krystyna , Jadwiga Podwysocka Dominika , Seebach Dieter
Published: January 2011

Fmoc‐β2hSer(tBu)‐OH was converted to Fmoc‐β2hSec(PMB)‐OH in five steps. To avoid elimination of HSeR, the selenyl group was introduced in the second last step (Fmoc‐β2hSer(Ts)‐OAll→Fmoc‐β2hSec(PMB)‐OAll). In a similar way, the N‐Boc‐protected compound was prepared. With the β2hSe‐derivatives, 21 β2‐amino‐acid building blocks with proteinogenic side chains are now available for peptide synthesis.
Inverse heat conduction problems by using particular solutions
Authors: Wen P.H. , Hon Y.C. , Xu Y.G.
Published: January 2011

Based on the method of fundamental solutions, we develop in this paper a new computational method to solve two‐dimensional transient heat conduction inverse problems. The main idea is to use particular solutions as radial basis functions (PSRBF) for approximation of the solutions to the inverse heat conduction problems. The heat conduction equations are first analyzed in the Laplace transformed domain and the Durbin inversion method is then used to determine the solutions in the time domain. Least‐square and singular value decomposition (SVD) techniques are adopted to solve the ill‐conditioned linear system of algebraic equations obtained from the proposed PSRBF method. To demonstrate the effectiveness and simplicity of this approach, several numerical examples are given with satisfactory accuracy and stability. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/htj.20335
Eco‐friendly synthesis of quinoxaline derivatives by grinding under solvent‐free conditions
Authors: Li Jun , Jiang Dan‐Na , Chen Jiu‐Xi , Liu Miao‐Chang , Ding Jin‐Chang , Wu Hua‐Yue
Published: January 2011

An efficient and facile synthesis of quinoxaline derivatives in excellent isolated yields by the condensation of 1,2‐diamines and 1,2‐diketones on grinding under solvent‐free conditions at ambient temperature has been developed. The important features of this method are that it is reasonably fast, very clean, high yielding, simple workup, and environmentally benign. J. Heterocyclic Chem., 00, 00 (2011).
Synthesis of an isomer of the renieramycin skeleton from L‐tyrosine
Authors: Liu Wei , Dong Wen Fang , Liao Xiang Wei , Guan Bao He , Liu Zhan Zhu
Published: January 2011

A new approach that tried to obviate the use of bromine protection groups was studied to synthesize (−)‐renieramycin G from L‐tyrosine. It was found that the first intermolecular Pictet–Spengler reaction proceeded successfully to give the correct tetrahydroisoquinoline precursor 6. However, the second intramolecular Pictet–Spengler cyclization step failed to give the desired product, and an isomer of the skeleton of the renieramycins was obtained via 12 steps starting from L‐tyrosine. J. Heterocyclic Chem., (2011).
An alternative total synthesis of pentosidine
Authors: Liu Yahua , Zhang Weihan , Sayre Lawrence M.
Published: January 2011

Pentosidine, a fluorescent advanced glycation endproduct that serves as a biomarker of diabetic complications, kidney dysfunction, oxidative stress, and aging and age‐related diseases, was synthesized from 2,3‐diaminopyridine and benzyloxycarbonyl (Cbz) protected chiral amino acidsNα‐Cbz‐lysine andNδ‐Cbz‐ornithine. Regioselective alkylation of 2‐(methylthio)imidazo[4,5‐b]pyridine, chlorination of methylthio group, and amination of 2‐chloro‐imidazo[4,5‐b]pyridine are the key steps. Hydantoin protection of amino acids was used and the deprotection under acidic condition was achieved in the presence of glycine. J. Heterocyclic Chem., (2011).
Morphology of hamstring torque‐time curves following acl injury and reconstruction: mechanisms and implications
Authors: Bryant Adam L. , Clark Ross A. , Pua Yong‐Hao
Published: January 2011

The purposes of this study were (i) to examine the effects of anterior cruciate ligament (ACL) status on hamstring force steadiness, peak hamstring strength, quadriceps (antagonist) activation, and physical performance, and (ii) to evaluate the associations of physical performance with hamstring steadiness and hamstring strength. Thirteen subjects with unilateral deficiency of the ACL (ACLD), 39 matched subjects with unilateral reconstructed ACL (ACLR; n = 25 with bone‐patella tendon‐bone (ACLR‐PT) graft and n = 14 with combined semitendinosus and gracilis tendon (ACLR‐STGT) graft) and 33 control subjects participated. Each subject performed maximal‐effort isokinetic knee flexion repetitions at 180° s−1 with electromyography (EMG) electrodes attached to their medial and lateral quadriceps muscles. Physical performance was assessed using the single‐limb long hop for distance. Wavelet‐derived mean instantaneous frequency (Mif) of flexor torque‐time curves was significantly (p < 0.05) higher (i.e., less smooth) in ACLR‐STGT subjects compared to the ACLD, ACLR‐PT and control subjects. No significant differences existed for peak hamstrings strength (i.e., peak torque produced) or quadriceps antagonist EMG activity. Positive correlations were identified between hamstrings force steadiness and quadriceps antagonist activity for ACLD (r = 0.797), ACLR‐PT (r = 0.467), and ACLR‐STGT (r = 0.628) subjects. For ACLR‐STGT subjects, reduced hamstrings force steadiness associated with poorer long‐hop performance (r = −0.695). Reduced steadiness amongst ACLR‐STGT subjects may reflect motor output variability of the antagonist (i.e., quadriceps dyskinesia) and/or agonist musculature—a maladaptive feature which potentially contributes to poorer single‐limb hop performance. Measures of hamstring force steadiness in combination with traditional measures of peak hamstring strength provide valuable clinical information regarding knee joint function following ACL injury/ACLR. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:907–914
Exercise enhances angiogenesis during bone defect healing in mice
Authors: Holstein Joerg H. , Becker Steven C. , Fiedler Martin , Scheuer Claudia , Garcia Patric , Histing Tina , Klein Moritz , Pohlemann Tim , Menger Michael D.
Published: January 2011

The aim of the present study was to investigate the effect of exercise on angiogenesis during bone defect healing in mice. We evaluated angiogenesis during cranial bone defect healing by intravital fluorescence microscopy (IVM) at days 0–21. To characterize the type of bone repair, we performed additional histomorphometric analyses at days 3–15. IVM was conducted in mice, which were housed in cages supplied with running wheels (exercise group; n = 7) and compared to IVM results of mice, which were housed in cages without running wheels (controls; n = 7). In the exercise group, we additionally performed correlation analyses between results of the IVM and the running distance. IVM showed an accelerated decrease of bone defect area in the exercise group compared to the control group. This was associated with a significantly higher blood vessel diameter in animals undergoing exercise at days 9 and 12 and a significant correlation between running distance and blood vessel density at day 9 (r = 0.74). Histomorphometry showed osseous bridging of the defect at day 9. The newly woven bone was covered by a neo‐periosteum containing those blood vessels, which were visible by IVM. We conclude that exercise accelerates bone defect healing and stimulates angiogenesis during bore repair. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1086–1092, 2011
Separation and purification of ergosterol and stigmasterol in Anoectochilus roxburghii (wall) Lindl by high‐speed counter‐current chromatography
Authors: Huang Liying , Cao Yangyuan , Xu Hui , Chen Guonan
Published: January 2011

Ergosterol and stigmasterol are the most common phytosterols in the traditional Chinese medicine. They are two major sterol compounds in Anoectochilus roxburghii (wall) Lindl (A. roxburghii) and have been proved to have many important biological activities. A method by using high‐speed counter‐current chromatography (HSCCC) has been successfully developed for separation and purification of ergosterol and stigmasterol in A. roxburghii simultaneously in this paper. The optimum conditions used in this method were as follows: The two‐phase solvent system consisted of n‐hexane–ethylacetate–butanol–methanol–water (3.5:0.3:0.5:2.5:0.3, v/v); the rotation speed was 900 rpm; the flow rate of the lower phase was 1.5 mL/min. About 36.5 mg of ergosterol and 43.6 mg of stigmasterol were obtained from 100 g of A. roxburghii. The purity of ergosterol and stigmasterol was examined to be 92.0 and 95.5%, respectively, by using HPLC. The chemical structures of these components were identified by UV spectra, FT‐IR, MS, 1H‐NMR and 13C‐NMR. The results demonstrated that high‐speed counter‐current chromatography was a feasible method to separate and purify ergosterol and stigmasterol from the herb. This separation and purification method was more effective than many other conventional techniques.
Low Thrombogenicity Coating of Nonwoven PET Fiber Structures for Vascular Grafts
Authors: Dimitrievska Sashka , Maire Marion , Diaz‐Quijada Gerardo A. , Robitaille Lucie , Ajji Abdellah , Yahia L'Hocine , Moreno Maria , Merhi Yahye , Bureau Martin N.
Published: January 2011

Vascular PET grafts (Dacron) have shown good performance in large vessels (≥6 mm) applications. To address the urgent unmet need for small‐diameter (2–6 mm) vascular grafts, proprietary high‐compliance nonwoven PET fiber structures were modified with various PEG concentrations using PVA as a cross‐linking agent, to fabricate non‐thrombogenic mechanically compliant vascular grafts. The blood compatibility assays measured through platelet adhesion (SEM and mepacrine dye) and platelet activation (morphological changes, P‐selectin secretion, and TXB2 production) demonstrate that functionalization using a 10% PEG solution was sufficient to significantly reduce platelet adhesion/activation close to optimal literature‐reported levels observed on carbon‐coated ePTFE.

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Isoconversional Glass Transition Kinetics and Fragility Determination of Poly[(ethylene 2,6‐naphthalate)‐co‐(butylene 2,6‐naphthalate)] Random Copolymers
Authors: Papageorgiou George Z. , Achilias Dimitris S. , Karayannidis George P.
Published: January 2011

Isoconversional methods were applied to DSC data to determine the effective activation energy, ΔE, for the glass transition in a series of PEBN random copolymers. It was revealed that ΔE varies rather significantly throughout the process, decreasing with temperature as well as with the amount of BN units in the copolymer chain. Moreover, the dynamic fragility, m, of PEBN copolymers was evaluated. Employing the scanning rate dependency of Tg it was found that as the amount of BN units in the copolymer increases, m gets lower values denoting more strong materials, while the inverse was concluded by applying the extrapolation of configurational entropy to zero method. Results of the later method were verified by tensile mechanical property measurements of the copolymers.

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Macromolecular Recognition: Discrimination between Human and Bovine Serum Albumins by Cyclodextrins
Authors: Oi Wataru , Isobe Mio , Hashidzume Akihito , Harada Akira
Published: January 2011

The interactions of cyclodextrins (CDs) with human serum albumin (HSA) and bovine serum albumin (BSA) were investigated by two‐dimensional nuclear Overhauser effect spectroscopy (2D NOESY), steady state fluorescence, isothermal titration calorimetry, and circular dichroism spectroscopy. 2D NOESY indicates that α‐CD and β‐CD, but not γ‐CD, interact with the aromatic amino acid residues on HSA. On the other hand, the 2D NOESY signals between CDs and BSA are not significantly correlated. Hence, CDs can discriminate the subtle protein structural differences of HSA and BSA.

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A Lipase‐Responsive Vehicle Using Amphipathic Polymer Synthesized with the Lipase as Catalyst
Authors: Ge Jun , Lu Diannan , Yang Cheng , Liu Zheng
Published: January 2011

We describe an enzyme‐responsive polymeric vehicle, which is of great interest in controlled drug delivery, biosensing, and other related areas. The polymer synthesized using lipase as catalyst in DMSO has a favorable molecular structure that is quickly hydrolyzed by lipase in aqueous phase, and allows a fast release of encapsulated molecules.

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Direct visualization of Parkinson's disease by in vivo human brain imaging using 7.0T magnetic resonance imaging
Authors: Cho Zang‐Hee , Oh Se‐Hong , Kim Jong‐Min , Park Sung‐Yeon , Kwon Dae‐Hyuk , Jeong Hye‐Jin , Kim Young‐Bo , Chi Je‐Geun , Park Chan‐Woong , Huston John , Lee Kendall H. , Jeon Beom S.
Published: January 2011

Parkinson's disease (PD) is a neurodegenerative disorder resulting from progressive loss of dopaminergic neurons in the substantia nigra (SN) pars compacta. Therefore, imaging of the SN has been regarded to hold greatest potential for use in the diagnosis of PD. At the 7.0T magnetic resonance imaging (MRI), it is now possible to delineate clearly the shapes and boundaries of the SN. We scanned eight early and two advanced PD patients, along with nine age‐matched control subjects, using a 7.0T MRI in an attempt to directly visualize the SN and quantify the differences in shape and boundaries of SN between PD subjects in comparison with the normal control subjects. In the normal controls, the boundaries between the SN and crus cerebri appear smooth, and clean “arch” shapes that stretch ventrally from posterior to anterior. In contrast, these smooth and clean arch‐like boundaries were lost in PD subjects. The measured correlation analyses show that, in PD patients, there is age‐dependent correlation and substantially stronger UPDRS motor score‐dependent correlation. These results suggest that, by using 7.0T MRI, it appears possible to use these visible and distinctive changes in morphology as a diagnostic marker of PD. © 2011 Movement Disorder Society
A significant wind shear event leading to aircraft diversion at the Hong Kong international airport
Authors: Chan P. W.
Published: January 2011

A significant wind shear event occurred in the early morning of 27 December 2009 at the Hong Kong International Airport (HKIA), leading to the diversion of three aircraft to the airport of Shenzhen (about 39 km to the north‐northwest of HKIA). This paper documents the meteorological observations and predictions for the event. The significant wind shear arose from disruption of the prevailing easterly to southeasterly flow by the complex terrain to the south of the airport. It was well captured by the Doppler Light Detection and Ranging (LIDAR) systems at HKIA and, as such, the aircraft were given sufficient warning about the occurrence of significant wind shear. The headwind changes along the glide paths as measured by the LIDAR were consistent with the aircraft measurements. The observations of the remote‐sensing instruments during the event, including the LIDAR, are described in the paper. Moreover, this paper discusses the possibility of including wind shear forecast information for flight planning purpose for this particular case. The forecast wind field near HKIA based on a high‐resolution numerical weather prediction (NWP) model is described. For the present wind shear event, it appears that the occurrence of terrain‐disrupted airflow near HKIA may be forecast about 6 h ahead. The timing of significant wind shear is, however, not reproduced well in the NWP forecast. Copyright © 2011 Royal Meteorological Society
Clinical Services in Environmental Pediatrics
Authors: Paulson Jerome A. , Gordon Lauren
Published: January 2011

Pediatric healthcare providers are confronted with environmental health problems frequently: the child with asthma exacerbated by the odor of paint in school or mouse antigen at home, the family who wants to know the risks and benefits of using different types of sunblock, or the community that asks the provider for advice on the potential health impacts of building the new elementary school next to the on‐ramp to the interstate highway. Pediatric providers have not been well trained to deal with these questions in medical or nursing schools, residency training, or continuing‐education settings. This article provides guidance on history taking, the physical examination, laboratory evaluations of patients and the environment, and making an assessment about and managing environmental health problems. Pediatric Environmental Health Specialty Units are discussed as a source of consultation and referral. The identification and utilization of evidence‐based resources are stressed and clinicians are cautioned about non–evidence‐based assessments such as clinical ecology and hair analysis and non–evidence‐based management strategies such as chelation for autism. Mt Sinai J Med 78:11–21, 2011. © 2011 Mount Sinai School of Medicine
A dual algorithm for shakedown analysis of plate bending
Authors: Tran Thanh Ngoc
Published: January 2011

In this paper, the duality between the lower and the upper bound shakedown analyses of plate bending is presented. Based on the duality theory, the shakedown load multiplier formulated by static theorem is proved actually to be the dual form of the shakedown load multiplier formulated by kinematic theorem. A dual algorithm based upon the von Mises yield criterion and a non‐linear optimization procedure is then developed to compute simultaneously both the upper and lower bounds of the plastic collapse limit and the shakedown limit. The DKQ plate bending element is used to discrete the problem field. Numerical examples are presented to show the excellent convergence and accuracy of solutions obtained by the present method. Copyright © 2011 John Wiley & Sons, Ltd.
A stabilized co‐rotational curved quadrilateral composite shell element
Authors: Li Z. X. , Liu Y. F. , Izzuddin B. A. , Vu‐Quoc L.
Published: January 2011

A new curved quadrilateral composite shell element using vectorial rotational variables is presented. An advanced co‐rotational framework defined by the two vectors generated by the four corner nodes is employed to extract pure element deformation from large displacement/rotation problems, and thus an element‐independent formulation is obtained. The present line of formulation differs from other co‐rotational formulations in that (i) all nodal variables are additive in an incremental solution procedure, (ii) the resulting element tangent stiffness is symmetric, and (iii) is updated using the total values of the nodal variables, making solving dynamic problems highly efficient. To overcome locking problems, uniformly reduced integration is used to compute the internal force vector and the element tangent stiffness matrix. A stabilized assumed strain procedure is employed to avoid spurious zero‐energy modes. Several examples involving composite plates and shells with large displacements and large rotations are presented to testify to the reliability, computational efficiency, and accuracy of the present formulation. Copyright © 2011 John Wiley & Sons, Ltd.