bluuebunny/crossref_metadata_2025 huggingface dataset:
Nanothermometers for Transmission Electron Microscopy – Fabrication and Characterization
Authors: Wang Chiu‐Yen , Chen Lih‐Juann
Published: August 2010

The fabrication and characterization of nanothermometers for use in transmission electron microscopy (TEM) are reviewed. Comparisons of different core–shell nanothermometers in terms of the working temperature range, growth conditions, and thermal expansion coefficients are made. The thermal stability of oxide compounds is discussed
Cyclopenta[a]quinolizine: A Novel Pseudoazulene with a Bridgehead Nitrogen Atom
Authors: Gormay Pavel V. , Rybakov Victor B. , Babaev Eugene V.
Published: August 2010

Cyclopenta[a]quinolizine, a novel tricyclic pseudoazulene, was prepared by reaction of cyclopentadienyllithium with oxazolo[3,2‐a]pyridinium or substituted pyridinium salts. Structural analysis (X‐ray analysis, NMR and UV spectroscopy) and DFT calculations confirm its highly dipolar nature (due to delocalization of the negative charge around the five‐membered ring) combined with partial localization of bonds in both six‐membered rings.
Management of the diffusion of 4‐methylumbelliferone across phases in microdroplet‐based systems for in vitro protein evolution
Authors: Wu Nan , Courtois Fabienne , Zhu Yonggang , Oakeshott John , Easton Chris , Abell Chris
Published: August 2010

Fluorongenic reagents based on 4‐methylumbelliferone (4‐MU) have been widely used for the detection of phosphatase, sulfatase, esterase, lipase and glycosidase activities in conventionally formatted enzyme assay systems. However, the sensitivity of assays based on these substrates is also potentially very useful in the microdroplet formats now being developed for high throughput in vitro evolution experiments. In this article, we report the investigation of diffusion of 4‐MU as a model dye from water‐in‐oil droplets and the internal aqueous phase of water‐in‐oil‐in‐water droplets in microfluidics. The effect of BSA in the aqueous phase on the diffusion of 4‐MU is also discussed. Based on these results, we provided here proof‐of‐concept of the reaction of the enzyme OpdA with the substrate coumaphos in water‐in‐oil‐in‐water droplets. In this double‐emulsion system, the reaction of OpdA and coumaphos was achieved by allowing coumaphos to diffuse from the continuous aqueous phase across the oil phase into the internal aqueous droplets.
Dietary influences on mutagenesis—Where is this field going?
Authors: Ferguson Lynnette R.
Published: August 2010

Early studies on dietary mutagenesis were mostly observational, with large numbers of potential dietary mutagens being identified from every conceivable dietary source. These included known dietary carcinogens such as aflatoxin B1 and benzo[a]pyrene, and hitherto unrecognized dietary mutagens, such as the pyrolysis products formed during the heating of proteinaceous materials (heterocyclic amines). The 1993 evaluation of 2‐amino‐3‐methyl‐3H‐imidazo(4,5‐j)quinoline as a probable human carcinogen by the International Agency for Research on Cancer was a landmark, as this was done in the absence of specific human carcinogenicity data, and strongly influenced by mutagenicity test data. In the 21st century, the field has moved from the identification of more and more mutagens, to molecular epidemiologic approaches that not only show a mutagenic effect but also seek to link it to a dietary (or environmental) cause. Effects of diet in stimulating chronic inflammation may lead to reactive species and thereby mutation as a secondary consequence, while dietary deficiencies and nutrient imbalances may be strong sources of mutagenesis. Recognition of the roles of nutrients in cell signaling processes and control of microRNAs suggest major influences on gene expression, in the absence of permanent DNA changes. Genome‐wide association studies have highlighted new pathways such as JAK/STAT signaling that profoundly influence genomic instability and responses to dietary mutagens. With improved methodologies for DNA sequencing and epigenetic changes, it is time to apply more sophisticated approaches to recognizing and proving the role of diet as a primary modulator of mutagenesis in humans. Environ. Mol. Mutagen., 2010. © 2010 Wiley‐Liss, Inc.
Aeolian sand strip mobility and protodune development on a drying beach: examining surface moisture and surface roughness patterns measured by terrestrial laser scanning
Authors: Nield Joanna M. , Wiggs Giles F.S. , Squirrell Robert S.
Published: August 2010

Ephemeral aeolian sand strips are commonplace on beaches. Their formation during high energy sand transport events often precedes the development of protodunes and their dynamics present interesting feedback mechanisms with surface moisture patterns. However, due to their temporary nature, little is known of their formation, mobility or the specifics of their interaction with beach surface characteristics. Similarly surface moisture has an important influence on sediment availability and transport in aeolian beach systems, yet it is difficult to quantify accurately due to its inherent variability over both short spatial and temporal scales. Whilst soil moisture probes and remote sensing imagery techniques can quantify large changes well, their resolution over mainly dry sand, close to the aeolian transport threshold is not ideal, particularly where moisture gradients close to the surface are large. In this study we employed a terrestrial laser scanner to monitor beach surface moisture variability during a three and a half hour period after a rain event and investigated relationships between bedform development, surface roughness and surface moisture. Our results demonstrate that as the beach surface dries, sand transport increases, with sediment erosion occurring at the wet/dry surface boundary, and deposition further downwind. This dynamic structure, dependent upon changing surface moisture characteristics, results in the formation of a rippled sand strip and ultimately a protodune. Our findings highlight dynamic mobility relationships and confirm the need to consider transient bedforms and surface moisture across a variety of scales when measuring aeolian transport in beach settings. The terrestrial laser scanner provides a suitable apparatus with which to accomplish this. Copyright © 2010 John Wiley & Sons, Ltd.
Trophodynamics of polybrominated diphenyl ethers and methoxylated polybrominated diphenyl ethers in a marine food web
Authors: Zhang Kun , Wan Yi , An Lihui , Hu Jianying
Published: August 2010

The current study measured the concentrations of 14 polybrominated diphenyl ethers (PBDEs) and eight methoxylated polybrominated diphenyl ethers (MeO-PBDEs) in a marine food web and estimated their trophic magnification factors (TMFs), to highlight the differences between invertebrates, fish, and seabirds. Concentrations of PBDEs were orders of magnitude greater in seabirds (184.07 ± 161.63 ng/g lipid wt) compared with invertebrates and fish (19.01 ± 14.14 ng/g lipid wt). Although the congener profiles in invertebrates, fish, and juvenile seabirds were dominated by BDE-47, the contributions of BDE-99 and BDE-153 in adult seabirds were also significant. Unlike PBDEs, however, higher average MeO-PBDE concentrations were detected in fish (126.27 ± 189.27 ng/g lipid wt) and bivalves (15.96 ± 11.82 ng/g lipid wt) than in seabirds (2.61 ± 2.87 ng/g lipid wt). Correlations between lipid-normalized PBDE concentrations and trophic levels confirmed that seven PBDE congeners were magnified in the invertebrate-fish-seabird food web and that PBDE concentrations increased at a much greater rate across trophic levels in seabirds than in invertebrates and fish. This result indicates that estimating TMFs of PBDEs separately for seabirds, invertebrates, and fish is preferable. For MeO-PBDEs, no significant relationships were obtained in the invertebrate-fish-seabird food web. Environ. Toxicol. Chem. 2010;29:2792–2799. © 2010 SETAC
Dissolved organic matter modulating the uptake, biotransformation, and elimination rates of pyrene inDaphnia magna
Authors: Ruotsalainen Anna-Maija , Akkanen Jarkko , Kukkonen Jussi V.K.
Published: August 2010

In the current study, the toxicokinetics of pyrene in Daphnia magna was determined in detail, and the role of dissolved organic matter (DOM) in these processes was investigated. Uptake, biotransformation, parent compound and metabolite elimination rates (ku, km, kep, kem), depuration rates, bioconcentration factors (BCFs), and biological half-lives were studied in one natural humic water, in two waters made from DOM isolates, and in DOM-free artificial fresh water. The daphnids were exposed to pyrene for 24 h and depurated for another 24 h. To analyze the data, the two-compartment model was used to obtain toxicokinetic parameters, and the depuration data were analyzed by linear regression. Extensive biotransformation of pyrene resulted in high metabolite concentration in the organisms (83% of total radioactivity) after 24 h exposure. Depuration of the parent compound seemed to be biphasic: at first, depuration was rapid, but after 4 to 10 h in uncontaminated water, the disappearance rate came close to zero. After a 24-h depuration time, 7.8% of the pyrene accumulated remained in the organism. Overall, the elimination of parent compound was faster than the elimination of metabolites, which might imply inefficient excretion of water-soluble biotransformation products from daphnids. The effect of DOM on accumulation of pyrene was seen in a decreased uptake rate, indicating lower bioavailability of the compound in waters that contain high-aromaticity DOM. In the same waters, DOM significantly accelerated pyrene biotransformation and overall elimination. Altogether, DOM appears to be able to affect toxicokinetics through mechanisms that are connected to interaction with the contaminant but also directly through interaction with biotransformation systems. Environ. Toxicol. Chem. 2010;29:2783–2791. © 2010 SETAC
The combined‐jamming model for IEEE 802.11 FH/MFSK networks
Authors: Kirachaiwanich D. , Liang Q.
Published: August 2010

In this paper, the expressions for calculating the bit error rate (BER) performance of noncoherent frequency‐hopped M‐ary frequency‐shift‐keying (NC‐FH/MFSK) receiver, subjected to independent multitone jamming (IMTJ) and partial‐band jamming (PBJ), are derived. We observe that the the jamming tones in IMTJ strategy are, in fact, equivalent to the cochannel interferences in the network of IEEE 802.11 NC‐FH/MFSK devices. Also, the major source of interference from outside of such network (coexisting network interference) is the IEEE 802.11 a/b/g devices whose signal is very similar to that of the jammer in PBJ strategy. Therefore, we combine the expressions for IMTJ and PBJ together and create a new combined‐jamming formula for determining the link performance in IEEE 802.11 NC‐FH/MFSK networks. As an example, we also illustrate the application of the new formula on the channel assignment (CA) problem in multiradio NC‐FH/MFSK wireless mesh networks. Because the combined‐jamming formula can take into account both the cochannel interference and the outside interference, it can predict fairly accurate BERs for determining appropriate channels in the network. Copyright © 2010 John Wiley & Sons, Ltd.
EWSR1‐POU5F1 fusion in soft tissue myoepithelial tumors. A molecular analysis of sixty‐six cases, including soft tissue, bone, and visceral lesions, showing common involvement of the EWSR1 gene
Authors: Antonescu Cristina R. , Zhang Lei , Chang Ning‐En , Pawel Bruce R. , Travis William , Katabi Nora , Edelman Morris , Rosenberg Andrew E. , Petur Nielsen G. , Cin Paola Dal , Fletcher Christopher D.M.
Published: September 2010

The diagnosis of myoepithelial (ME) tumors outside salivary glands remains challenging, especially in unusual clinical presentations, such as bone or visceral locations. A few reports have indicated EWSR1 gene rearrangement in soft tissue ME tumors, and, in one case each, the fusion partner was identified as either PBX1 or ZNF444. However, larger studies to investigate whether these genetic abnormalities are recurrent or restricted to tumors in soft tissue locations are lacking. Sixty‐six ME tumors mainly from soft tissue (71%), but also from skin, bone, and visceral locations, characterized by classic morphological features and supporting immunoprofile were studied. Gene rearrangements in EWSR1, FUS, PBX1, and ZNF444 were investigated by fluorescence in situ hybridization. EWSR1 gene rearrangement was detected in 45% of the cases. A EWSR1‐POU5F1 fusion was identified in a pediatric soft tissue tumor by 3′Rapid Amplification of cDNA Euds (RACE) and subsequently confirmed in four additional soft tissue tumors in children and young adults. An EWSR1‐PBX1 fusion was seen in five cases, whereas EWSR1‐ZNF444 and FUS gene rearrangement was noted in one pulmonary tumor each. In conclusion, EWSR1 gene rearrangement is a common event in ME tumors arising outside salivary glands, irrespective of anatomical location. EWSR1‐negative tumors were more often benign, superficially located, and showed ductal differentiation, suggesting the possibility of genetically distinct groups. A subset of soft tissue ME tumors with clear cell morphology harbor an EWSR1‐POU5F1 fusion, which can be used as a molecular diagnostic test in difficult cases. These findings do not support a pathogenetic relationship between soft tissue ME tumors and their salivary gland counterparts. © 2010 Wiley‐Liss, Inc.
BMI and fracture risk in older men: The osteoporotic fractures in men study (MrOS)
Authors: Nielson Carrie M , Marshall Lynn M , Adams Annette L , LeBlanc Erin S , Cawthon Peggy M , Ensrud Kristine , Stefanick Marcia L , Barrett-Connor Elizabeth , Orwoll Eric S ,   for the Osteoporotic Fractures in Men Study (MrOS) Research Group
Published: September 2010

Low body mass index (BMI) is a risk factor for fracture, but little is known about the association between high BMI and fracture risk. We evaluated the association between BMI and fracture in the Osteoporotic Fractures in Men Study (MrOS), a cohort of 5995 US men 65 years of age and older. Standardized measures included weight, height, and hip bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA); medical history; lifestyle; and physical performance. Only 6 men (0.1%) were underweight (<18.5 kg/m2); therefore, men in this category were excluded. Also, 27% of men had normal BMI (18.5 to 24.9 kg/m2), 52% were overweight (25 to 29.9 kg/m2), 18% were obese I (30 to 34.9 kg/m2), and 3% were obese II (35 to 39.9 kg/m2). Overall, nonspine fracture incidence was 16.1 per 1000 person-years, and hip fracture incidence was 3.1 per 1000 person-years. In age-, race-, and BMD-adjusted models, compared with normal weight, the hazard ratio (HR) for nonspine fracture was 1.04 [95% confidence interval (CI) 0.87–1.25] for overweight, 1.29 (95% CI 1.00–1.67) for obese I, and 1.94 (95% CI 1.25–3.02) for obese II. Associations were weaker and not statistically significant after adjustment for mobility limitations and walking pace (HR = 1.02, 95% CI 0.84–1.23, for overweight; HR = 1.12, 95% CI 0.86–1.46, for obese I, and HR = 1.44, 95% CI 0.90–2.28, for obese II). Obesity is common among older men, and when BMD is held constant, it is associated with an increased risk of fracture. This association is at least partially explained by worse physical function in obese men. © 2011 American Society for Bone and Mineral Research.
Performance of 3D‐space‐based atoms‐in‐molecules methods for electronic delocalization aromaticity indices
Authors: Heyndrickx Wouter , Salvador Pedro , Bultinck Patrick , Solà Miquel , Matito Eduard
Published: August 2010

Several definitions of an atom in a molecule (AIM) in three‐dimensional (3D) space, including both fuzzy and disjoint domains, are used to calculate electron sharing indices (ESI) and related electronic aromaticity measures, namely,Iringand multicenter indices (MCI), for a wide set of cyclic planar aromatic and nonaromatic molecules of different ring size. The results obtained using the recent iterative Hirshfeld scheme are compared with those derived from the classical Hirshfeld method and from Bader's quantum theory of atoms in molecules. For bonded atoms, all methods yield ESI values in very good agreement, especially for C–C interactions. In the case of nonbonded interactions, there are relevant deviations, particularly between fuzzy and QTAIM schemes. These discrepancies directly translate into significant differences in the values and the trends of the aromaticity indices. In particular, the chemically expected trends are more consistently found when using disjoint domains. Careful examination of the underlying effects reveals the different reasons why the aromaticity indices investigated give the expected results for binary divisions of 3D space. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011.
Synthesis and pharmacological properties of N‐substituted‐N′‐(4,6‐dimethylpyrimidin‐2‐yl)‐thiourea derivatives and related fused heterocyclic compounds
Authors: Saeed Sohail , Rashid Naghmana , Jones Peter G. , Tahir Arifa
Published: September 2010

A series of new N‐Substituted‐N′‐(4,6‐dimethylpyrimidin‐2‐yl)‐thiourea derivatives (3a, 3b, 3c, 3d) and related fused heterocyclic compounds (4a, 4b, 4c, 4d) were synthesized using tetrabutylammonium bromide as phase transfer catalyst (PTC). N‐[(2E)‐5,7‐dimethyl‐2H‐[1,2,4] thiadiazolo [2,3‐a] pyrimidin‐2‐ylidene] derivatives (4a, 4b, 4c, 4d) were prepared by oxidative cyclization of 3a, 3b, 3c, 3d. The structures of these novel compounds were characterized by IR, 1H NMR, 13C NMR, mass spectrometry, and the elemental analysis. The crystal structures were determined from single crystal X‐ray diffraction data. The results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms and showed higher activity against fungi than bacteria. Compounds 3d and 3a exhibited the greatest antimicrobial activity. J. Heterocyclic Chem., 2011.
A facile synthesis of novel thiazolo[4,5‐d]pyrimidin‐7‐ones
Authors: Liang Ying , He Hong‐Wu , Yang Zi‐Wen
Published: September 2010

Sixteen 5‐alkylamino‐3,6‐diaryl‐2‐thioxo‐2,3,6,7‐tetrahydrothiazolo[4,5‐d]pyrimidin‐7‐ones 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i, 4j, 4k, 4l, 4m, 4n, 4o, 4p were designed and easily synthesized via a tandem aza‐Wittig reaction. The iminophosphorane 2, obtained from reaction of 1 with triphenylphosphine, hexachloroethane and Et3N, reacted with aromatic isocyanate to give carbodiimide 3. carbodiimide 3 reacted with alkylamines to provide the title compounds in 45–61% isolated yields in presence of catalytic amount of ethoxide. The structures of compounds 4 were confirmed by 1H NMR, IR, MS, and elemental analysis. J. Heterocyclic Chem., 2011.
The evolution of volatile compounds profile of “Toscano” dry‐cured ham during ripening as revealed by SPME‐GC‐MS approach
Authors: Pugliese C. , Sirtori F. , Calamai L. , Franci O.
Published: August 2010

The volatile compounds profile is an important feature for the characterization of dry‐cured hams. Some minor typical Italian products, such as ‘Toscano’ ham, have been poorly studied in regards to their composition of volatile compounds. In this article, we studied the evolution of the aromatic profile of ‘Toscano’ dry‐cured ham by solid‐phase microextraction‐gas chromatographic‐mass spectrometry (SPME‐GC‐MS) with ripening. Ten right thighs were cured according to the ‘Toscano’ PDO protocol, sampled at 0, 1, 3, 6 and 12 months and submitted to volatile compounds analysis by SPME with a Divinylbenzene (DVB)/Carboxen/Polydimethylsiloxane (PDMS) 75‐µ Stable Flex fibre. An Agilent 5975C mass selective detector (MSD) spectrometer with electron ionization (EI) source operating in scan mode within the m/z 29–350 range was used for data collection. Seven internal standards, either deuterium labeled or absent in the specimens and chosen to represent low or high boiling esters, alcohols, acids or phenols, were added to the homogenized samples and used to normalize the SPME fibre response to account for response changes upon wearing. Linear calibrations were obtained in this way for selected representative compounds. Over 60 compounds belonging to esters, aldehydes, organic acids, ketones and alcohols were identified by comparison with spectral libraries and Kovats indices. Aldehydes were the most represented chemical family, followed by organic acids, alcohols, ketones and esters. The aldehydes and ketones increased during the first 3 months, when the larger formation of volatiles occurred. For other families, the evolution over time was less evident. The principal component and discriminant analyses of the aromatic profile were effective in classifying the hams at 0, 6 or 12 months of ripening while for 1 and 3 months' samples a partial overlapping was shown. These results represent the first characterization of ‘Toscano’ ham and may constitute the basis to identify the best ripening time and define an analytical quality standard for this typical ham. Copyright © 2010 John Wiley & Sons, Ltd.
Spatial and temporal temperature trends on the Yunnan Plateau (Southwest China) during 1961–2004
Authors: Fan Ze‐Xin , Bräuning Achim , Thomas Axel , Li Jin‐Bao , Cao Kun‐Fang
Published: August 2010

Monthly mean (TEM), maximum (Tmax) and minimum (Tmin) surface air temperatures at 119 meteorological stations on the Yunnan Plateau (YP, Southwest China) were analysed for temporal trends and spatial variation patterns during the period 1961–2004. Linear trend analyses revealed that annual temperature over the YP increased at a rate of 0.3 °C/decade during the period 1961–2004, while warming trend of 0.33 °C/decade and 0.26 °C/decade was observed for winter and summer temperatures, respectively. Warming trends of nighttime minimum temperature are more pronounced than those of daytime maximum temperature, especially during winter season. Consequently, a decreasing trend of diurnal temperature ranges (DTR = Tmax − Tmin) was observed. Five spatial patterns of temperature variability were objectively defined by rotated empirical orthogonal function (EOF) analysis, which are associated with distinct temporal temperature variations and geographical area over the YP. Annual temperature increases were found to be most pronounced in the southern and northwestern (high‐elevation) parts of the YP, whereas the hot‐dry valleys along the Yangtze and Red River basins experienced cooling during the past four decades. Copyright © 2010 Royal Meteorological Society
The effects of bevacizumab on postoperative complications in patients undergoing colorectal and pancreatic cancer resection
Authors: Cheon E.C. , Small W. , Strouch M.J. , Krantz S.B. , Rademaker A. , Mulcahy M.F. , Benson A.B. , Bentrem D.J. , Talamonti M.S.
Published: September 2010

Bevacizumab (Avastin™; rhuMab VEGF), a monoclonal antibody targeting vascular endothelial growth factor (VEGF), has seen increased use in the perioperative treatment of colorectal and pancreatic cancer. Little is known, however, regarding its impact on surgical outcomes in patients undergoing resection. The objective of this review was to examine if the addition of bevacizumab to existing neoadjuvant regimens increases morbidity after cancer resection. J. Surg. Oncol. 2010;102:539–542. © 2010 Wiley‐Liss, Inc.
Deterrents to tourism development in Iran
Authors: Morakabati Yeganeh
Published: September 2010

There are parts of the Middle East that can be regarded as being among the least preferred tourism destinations in the world. Research shows that travellers' perceptions of the region, as a whole, have been damaged and that, for some nations, the situation has gone from bad to worse. The combination of a hard‐line attitude towards religion, oil and water shortages have led to the onset of war and conflict, either among countries within the region, or have resulted in countries from within the region having conflicts with countries located outside of the region. This paper looks at the Middle East in general and Iran in particular in order to review its tourism potential and explains how the process of its development as a tourism destination has been hampered. This research also attempts to discover why, in spite of several attempts by the Iranian government, tourism has failed to develop to its true potential. The research is informed by a questionnaire survey of travellers together with a Mini‐Delphi Study of tourism academics. Copyright © 2010 John Wiley & Sons, Ltd.
Stabilisation of hydrogen bonding in polypropylene glycol at EHL contact region
Authors: Takiwatari Koji , Nanao Hidetaka , Suzuki Eiichi , Mori Shigeyuki
Published: August 2010

In the present work, the stabilisation of hydrogen bonding of polypropylene glycol at elastohydrodynamic lubrication (EHL) contact was investigated by in situ observation with a micro‐Fourier transform infrared spectrometer, and the effect of hydrostatic pressure on infrared (IR) spectra was confirmed using a diamond anvil cell. Polypropylene glycols with different molecular weights were used as sample oils. Polypropylene glycol molecules interact with themselves by hydrogen bonding with their hydroxyl groups. Stability of the hydrogen bonding is observed by IR peak shift of the O–H stretching mode (3400–3700 cm−1). In the case of the dynamic condition under EHL, the C–H stretching mode shifted to a higher wavenumber, whereas the O–H stretching mode shifted to a lower wavenumber at the Hertzian contact region. This result means that the hydrogen bonding of polypropylene glycol was stabilised under high pressure, and the stabilisation of hydrogen bonding by pressure was dependent on the molecular weight of polypropylene glycol. Copyright © 2010 John Wiley & Sons, Ltd.
Fabrication of Bioactive Composite Scaffolds by Electrospinning for Bone Regeneration
Authors: Nandakumar Anandkumar , Fernandes Hugo , de Boer Jan , Moroni Lorenzo , Habibovic Pamela , van Blitterswijk Clemens A.
Published: August 2010

Electrospun scaffolds are widely used for various biomedical applications. In this study, we prepared electrospun bioactive composite scaffolds combining hydroxyapatite, collagen (Col) and a synthetic polymer—PolyActive™—to mimic naturally occurring extracellular matrix for in situ bone regeneration. Human mesenchymal stem cells (hMSCs) adhered and proliferated on these scaffolds. Cells on all scaffold types showed an increased metabolic activity with time. On day 4, the metabolic activity of cells cultured on PolyActive™ (PA)–hydroxyapatite (HA)–Col in 1,1,1,3,3,3‐hexafluoro‐2‐propanolhexafluoro‐2‐propanol (HFIP) was significantly higher than that of cells grown on PA–Col samples. Furthermore, on day 6, cells on PA–HA–Col in HFIP showed significantly higher metabolic activity than those on PA and PA–Col scaffolds. Quantitative PCR analysis for a panel of osteogenic genes showed statistically significant differences between scaffolds. Cells cultured on PA–HA scaffolds had a significantly higher osteonectin and RunX2 expression compared to those on PA–HA–Col scaffolds. Cells on PA–HA–Col in HFIP scaffolds had significantly higher expression of alkaline phosphatase (ALP) and Col 1 compared to PA and PA–Col scaffolds respectively. The bone morphogenetic protein‐2 and S100A4 expression of PA–Col and PA–HA–Col constructs was significantly lower than the basal level expression of cells on PA scaffolds. Although not statistically significant in all cases, cells cultured on PA–HA–Col in HFIP and PA–HA scaffolds had the highest expression for most of the genes analysed. The results of the study demonstrate that bioactive composite scaffolds prepared by electrospinning could find potential use in bone regeneration applications.

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Root‐mean‐square‐deviation‐based rapid backbone resonance assignments in proteins
Authors: Rout Ashok K. , Barnwal Ravi P. , Agarwal Geetika , Chary Kandala V. R.
Published: August 2010

We have shown that the methodology based on the estimation of root‐mean‐square deviation (RMSD) between two sets of chemical shifts is very useful to rapidly assign the spectral signatures of 1HN, 13Cα, 13Cβ, 13C′, 1Hα and 15N spins of a given protein in one state from the knowledge of its resonance assignments in a different state, without resorting to routine established procedures (manual and automated). We demonstrate the utility of this methodology to rapidly assign the 3D spectra of a metal‐binding protein in its holo‐state from the knowledge of its assignments in apo‐state, the spectra of a protein in its paramagnetic state from the knowledge of its assignments in diamagnetic state and, finally, the spectra of a mutant protein from the knowledge of the chemical shifts of the corresponding wild‐type protein. The underlying assumption of this methodology is that, it is impossible for any two amino acid residues in a given protein to have all the six chemical shifts degenerate and that the protein under consideration does not undergo large conformational changes in going from one conformational state to another. The methodology has been tested using experimental data on three proteins, M‐crystallin (8.5 kDa, predominantly β‐sheet, for apo‐ to holo‐state), Calbindin (7.5 kDa, predominantly α‐helical, for diamagnetic to paramagnetic state and apo to holo) and EhCaBP1 (14.3 kDa, α‐helical, the wild‐type protein with one of its mutant). In all the cases, the extent of assignment is found to be greater than 85%. Copyright © 2010 John Wiley & Sons, Ltd.
Structure elucidation of new acacic acid‐type saponins from Albizia coriaria
Authors: Noté Olivier Placide , Chabert Philippe , Pegnyemb Dieudonné Emmanuel , Weniger Bernard , Lacaille‐Dubois Marie‐Aleth , Lobstein Annelise
Published: August 2010

Three new acacic acid derivatives, named coriariosides C, D, and E (1–3) were isolated from the roots of Albizia coriaria. Their structures were elucidated on the basis of extensive 1D‐ and 2D‐NMR studies and mass spectrometry as 3‐O‐[β‐D‐xylopyranosyl‐(1 → 2)‐β‐D‐fucopyranosyl‐(1 → 6)‐2‐(acetamido)‐2‐deoxy‐β‐D‐glucopyranosyl]‐21‐O‐{(2E,6S)‐6‐O‐{4‐O‐[(2E,6S)‐2,6‐dimethyl‐ 6‐O‐(β‐D‐quinovopyranosyl)octa‐2,7‐dienoyl]‐4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐O‐(β‐D‐quinovopyranosyl)octa‐2,7‐dienoyl]‐β‐D‐quinovopyranosyl}‐2,6‐dimethylocta‐2,7‐dienoyl}acacic acid 28‐O‐β‐D‐xylopyranosyl‐(1 → 4)‐α‐L‐rhamnopyranosyl‐(1 → 2)‐β‐D‐glucopyranosyl ester (1), 3‐O‐{β‐D‐fucopyranosyl‐(1 → 6)‐[β‐D‐glucopyranosyl‐(1 → 2)]‐β‐D‐glucopyranosyl}‐21‐O‐{(2E,6S)‐6‐O‐{4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐O‐(β‐D‐quinovopyranosyl)octa‐2,7‐dienoyl]‐4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐O‐(β‐D‐quinovopyranosyl)octa‐2,7‐dienoyl]‐β‐D‐quinovopyranosyl}‐2,6‐dimethylocta‐2,7‐dienoyl}acacic acid 28‐O‐α‐L‐rhamno pyranosyl‐(1 → 2)‐β‐D‐glucopyranosyl ester (2), and 3‐O‐[β‐D‐fucopyranosyl‐(1 → 6)‐β‐D‐glucopyranosyl]‐21‐O‐{(2E,6S)‐6‐O‐{4‐O‐[(2E,6S)‐2,6‐dimethyl‐6‐O‐(β‐D‐quinovopyranosyl)octa‐2,7‐dienoyl)‐β‐D‐quinovopyranosyl]octa‐2,7‐dienoyl}acacic acid 28‐O‐β‐D‐glucopyranosyl ester (3). Copyright © 2010 John Wiley & Sons, Ltd.
Cohesive‐frictional model for bond and splitting action of prestressing wire
Authors: Gálvez J. C. , Benítez J. M. , Casati M. J. , Tork B. S. , Cendón D. A.
Published: September 2010

This paper presents a numerical procedure for bond between indented wires and concrete, and the coupled splitting process of the surrounding concrete. The bond model is an interface, non‐associative, plasticity model. It is coupled with a cohesive fracture model for concrete to take into account the splitting of such concrete. Bond between steel and concrete is fundamental for the transmission of stresses between both materials in precast prestressed concrete. Indented wires are used to improve the bond in these structural elements. The radial component of the prestressing force, increased by Poisson's effect, may split the surrounding concrete, decreasing the wire confinement and diminishing the bonding. The combined action of the bond and the splitting is studied with the proposed model. The results of the numerical model are compared with the results of a series of tests, such as those which showed splitting induced by the bond between wire and concrete. Tests with different steel indentation depths were performed. The numerical procedure accurately reproduces the experimental records and improves knowledge of this complex process. Copyright © 2010 John Wiley & Sons, Ltd.
SNMP‐based enterprise IP network topology discovery
Authors: Pandey Suman , Choi Mi‐Jung , Won Young J. , Won‐Ki Hong James
Published: August 2010

Precise network topology information is required to perform management activities such as fault detection, root cause analysis, performance monitoring, and load balancing in enterprise networks. To accomplish these management tasks, both network discovery and connectivity information are essential. This paper examines various problems with the existing topology discovery mechanisms and proposes an SNMP‐based approach to discover physical as well as logical topology. We present algorithms for identifying network device types and discovering connectivity among them. The connectivity of end host and management information base (MIB)‐enabled devices with switches and routers is discussed and evaluated. We also present an algorithm for discovering logical topology, such as VLAN and subnet connectivity. Finally, we present a combination of graph and tree layouts, to visualize connectivity information. Copyright © 2010 John Wiley & Sons, Ltd.
Bone reactions on a pliocene cetacean rib indicate short‐term survival of predation event
Authors: Kallal R. J. , Godfrey S. J. , Ortner D. J.
Published: August 2010

There is little osteological evidence of non‐lethal predation events in the archaeological or vertebrate paleontological record. A small section of Pliocene cetacean rib collected from the Yorktown Formation within the PCS Phosphate Mine (formerly Lee Creek Mine), Aurora, North Carolina, U.S.A., shows evidence of this kind of trophic interaction. In this case study, we offer a diagnosis of bone traumatic pathology in which three bone‐forming lesions on the partial rib are interpreted as the reaction to a bite inflicted by a macro‐predator, the first such report from a marine environment. In addition to the three well‐defined lesions, a thin layer of woven bone covers much of the remaining cortical bone. The combination of the three bone‐forming lesions and the thin layer of woven bone suggest the presence of an inflammatory process almost certainly caused by infection secondary to the trauma. Survival following the traumatic event was probably less than 6 weeks. The Neogene chondrichthyan fauna from this locality preserves several large predators, includingCarcharocles megalodon,Carcharodon carcharias,Isurus xiphidonandParotodus benedeni, which were all capable, at least in terms of their size, of having bitten the cetacean. Although most of the odontocetes known from the Yorktown Formation were too small to have inflicted this wound, some of the physeterids may have been large enough to have caused the lesions on the partial rib. This evidence of predation in Pliocene whale bone raises the possibility of similar lesions being found in whale bone recovered from archaeological sites. Copyright © 2010 John Wiley & Sons, Ltd.
LQ control of rectangular descriptor systems: Numerical algorithm and existence results
Authors: Stefanovski Jovan
Published: August 2010

We present a structure‐preserving numerical algorithm, based on using orthogonal matrices, and sufficient conditions for LQ control of rectangular descriptor systems. The sufficient conditions are quite general: stabilizability, impulse controllability, generalizations of detectability and impulse observability. The solution in the case of wide descriptor system differs from the solution of tall descriptor system. Copyright © 2010 John Wiley & Sons, Ltd.
An hp‐adaptive pseudospectral method for solving optimal control problems
Authors: Darby Christopher L. , Hager William W. , Rao Anil V.
Published: August 2010

An hp‐adaptive pseudospectral method is presented for numerically solving optimal control problems. The method presented in this paper iteratively determines the number of segments, the width of each segment, and the polynomial degree required in each segment in order to obtain a solution to a user‐specified accuracy. Starting with a global pseudospectral approximation for the state, on each iteration the method determines locations for the segment breaks and the polynomial degree in each segment for use on the next iteration. The number of segments and the degree of the polynomial on each segment continue to be updated until a user‐specified tolerance is met. The terminology ‘ hp’ is used because the segment widths (denoted h) and the polynomial degree (denoted p) in each segment are determined simultaneously. It is found that the method developed in this paper leads to higher accuracy solutions with less computational effort and memory than is required in a global pseudospectral method. Consequently, the method makes it possible to solve complex optimal control problems using pseudospectral methods in cases where a global pseudospectral method would be computationally intractable. Finally, the utility of the method is demonstrated on a variety of problems of varying complexity. Copyright © 2010 John Wiley & Sons, Ltd.
Public–private partnerships and developing‐country agriculture: Evidence from the international agricultural research system
Authors: Spielman David J , Hartwich Frank , Grebmer Klaus
Published: August 2010

This study examines the role of public–private partnerships (PPPs) in promoting pro‐poor productivity‐enhancing technological innovation in the international agricultural research system. The study examines the extent to which PPPs are being used to overcome market and institutional failures that otherwise inhibit the development and dissemination of technologies targeted specifically to small‐scale, resource‐poor farmers in developing countries. Drawing on a survey of 75 PPP projects in the international system, findings suggest that while PPPs are changing the way the system manages its research agenda, few partnerships lead to joint innovation processes with the private sector. This indicates the need for closer examination of organizational practices, cultures, and incentives in the international agricultural research system. Copyright © 2010 John Wiley & Sons, Ltd.
Non‐surfactant template‐directed synthesis of SiO2‐polyimide hybrid self‐standing films with ordered mesoporous structure
Authors: Dai Xin , Geng Lei , Fu Yuqin , Liu Dan , Lü Changli
Published: August 2010

The silica‐PI hybrid self‐standing films with ordered mesoporous structure have been prepared by using dibenzoyl‐L‐tartaric acid (L‐DBTA) as non‐surfactant template under mild sol–gel route. Polyimide matrix was obtained from polyamic acid (PAA) via thermal imidization process and the template was removed in this process. The PI‐based hybrid film with 20 wt% SiO2 obtained from DBTA presented the ordered mesoporous channels with average pore size of about 2.0 nm and BET surface area of 1167 m2/g. FTIR and SEM studies indicated that the hydrogen bond interaction between the carboxylic groups of DBTA and benzamide bonds of PAA made the PAA possibly participate in the assembly process of the aggregates of the non‐surfactant template molecules. The mechanical, thermal and some physical properties of these hybrid films materials were also characterized. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation and characterization of nano‐platelet‐like hydroxyapatite/gelatin nanocomposites
Authors: Wan Yizao , Zuo Guifu , Liu Chao , Li Xiaolei , He Fang , Ren Kaijing , Luo Honglin
Published: August 2010

Nature has succeeded in creating numerous bionanocomposites such as bones and teeth consisting of nano‐platelets and biopolymers. Understanding of the mechanisms of formation and of the relation between structure and properties is vital for development of new materials for biomedical and engineering applications. In this work, varying contents of nano‐platelet‐like hydroxyapatite (HAp) has been used to reinforce gelatin (Gel) to produce nanocomposites. The prepared HAp/Gel nanocomposites were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric (TG/DTG) analyses. XRD, TEM, and FTIR results confirm the synthesis of intercalated and exfoliated nanostructures depending on the amount of gelatin. TG results reveal that the intercalated HAp/gelatin nanocomposites show improved thermal properties as compared to pristine gelatin. The results reported here can be expanded to other HAp–polymer systems, thus paving a new way of designing and fabricating biomemitic nanocomposites for future engineering and particularly for biomedical applications. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation, characterization, and properties of poly(thioether ether ketone imide)s from isomeric bis(chlorophthalimide)s
Authors: Wei Haibing , Wu Xueshi , Hu Benlin , Fang Xingzhong
Published: August 2010

A series of novel poly(thioether ether ketone imide)s (PTEKIs) bearing the thioether and ketone groups with high molecular weights (Mw: 87,800–150,100 g/mol) were synthesized by aromatic nucleophilic substitution reaction. The polymers were characterized by Fourier transform infrared spectra (FT‐IR), 1H NMR, GPC, and elemental analysis. The composition of the copolymers varied systematically in order to study its relation with polymer properties. Increase in the content of 3‐substituted phthalimide moiety in the polymer backbone improves the solubility in tested solvents, and increases the glass transition temperature (Tg), whereas copolymers with high content of 3‐substituted phthalimide demonstrated to be inferior thermal stability. The PTEKI films also exhibited good optical transparency, including the cutoff wavelengths lower than 400 nm and transmittances higher than 77% at 450 nm. Copyright © 2010 John Wiley & Sons, Ltd.
Comparative study of the optical, electrochemical, electrolumiscent, and photovoltaic properties of dendritic pendants modified poly(p‐phenylene vinylene)s
Authors: Tan Zhanao , Zhang Wenqing , Qian Deping , Zheng Hua , Xiao Shengqiang , Li Yongfang , Tang Rupei , Xi Fu
Published: August 2010

In this study, the optical, electrochemical, electrolumiscent, and photovoltaic properties of a series of poly(p‐phenylene vinylene) (PPV) derivatives bearing different dendritic pendants, poly{2‐[3′,5′‐bis(2″‐ethylhexyloxy)benzyloxy]‐1,4‐phenylenevinylene} (BE‐PPV), poly{2‐[2′,5′‐bis(3″,7″‐dimethyl)octyloxy]‐1,4‐phenylenevinylene} (BD‐PPV), poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylenevinylene] (MEH‐PPV), poly{2‐[3′,5′‐bis(2″‐ethylhexyloxy)benzyloxy]‐1,4‐phenylenevinylene}‐co‐poly[2‐methoxy‐5‐(2′‐ethylhexyloxy)‐1,4‐phenylenevinylene] (BE‐co‐MEH‐PPV), and poly{2‐[2′,5′‐bis(3″,7″‐dimethyl)octyloxy]‐1,4‐phenylenevinylene}‐co‐poly[2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐1,4‐phenylenevinylene] (BD‐co‐MDMO‐PPV), were investigated. The steric pendants strongly affect the absorption spectra, photoluminescence (PL) sepctra, the onset oxidation/reduction potentials, and further affect the electrolumiscent and photovoltaic properties. Copolymerization can reduce the steric effect and improve the electrolumiscent and photovoltaic properties. The brightness of light‐emitting diodes base on copolymer BE‐co‐MEH‐PPV and BD‐co‐MDMO‐PPV reached 3988 and 3864 cd/m2, respectively, much higher than that based on homopolymer BE‐PPV (523 cd/m2) and BD‐PPV (333 cd/m2), also higher than that based on MEH‐PPV (3788 cd/m2). The power conversion efficiency (PCE) of solar cells based on BE‐co‐MEH‐PPV and BD‐co‐MDMO‐PPV reached 1.41, 0.76%, respectively, much higher than that based on BE‐PPV (0.24%) and BD‐PPV (0.14%). Copyright © 2010 John Wiley & Sons, Ltd.
Simultaneous analysis of diosgenin and sarsasapogenin in Asparagus officinalis byproduct by thin‐layer chromatography
Authors: Wang Liwei , Wang Xiaodong , Yuan Xiaofan , Zhao Bing
Published: August 2010

Introduction – Asparagus officinalis L. has several biological activities including antifungal, antiviral and antitumoral activities due to the steroidal saponins. Normally diosgenin and sarsasapogenin are analysed separately by thin‐layer chromatography or high‐performance liquid chromatography (HPLC‐UV or HPLC‐ELSD), which is time‐consuming and expensive, so we need to find a rapid solution to this problem.

Objective – To develop a sensitive, rapid and validated TLC method for simultaneous detection and quantification of diosgenin and sarsasapogenin.

Methodology – Samples were prepared by extraction of A. officinalis with 70% aqueous ethanol to get steroidal saponins, and then hydrolysed using 36 mL 2 m hydrochloric acid for 3 h. The hydrolysis product was extracted with chloroform, and then analysed by TLC, the results of which were verified by HPLC and HPLC‐MS.

Results – The retention factor (Rf) of diosgenin and sarsasapogenin on TLC plate were 0.49 and 0.6, respectively. After calculation from the regression equation of the standard curve, the contents of diosgenin and sarsasapogenin in the A. officinalis extract were 0.27–0.46 and 0.11–0.32%, respectively.

Conclusion – The study showed that thin‐layer chromatography can be applied for the determination of diosgenin and sarsasapogenin in the oldest tissue of A. officinalis, and also can be conducted for screening of sapogenin in other plant or extracts. Copyright © 2010 John Wiley & Sons, Ltd.
Determination and comparative analysis of major iridoids in different parts and cultivation sources of Morinda citrifolia
Authors: Deng Shixin , West Brett J. , Palu 'Afa K. , Jensen C. Jarakae
Published: August 2010

Introduction – Noni is a medicinal plant with a long history of use as a folk remedy in many tropical areas, and is attracting more attention worldwide. A comprehensive study on the major phytochemicals in different plant parts (fruit, leaf, seed, root and flower) and sources is of great value for fully understanding their diverse medicinal benefits.

Objective – To quantitatively determine the major iridoid components in different parts of noni plants, and compare iridoids in noni fruits collected from different tropical areas worldwide.

Methodology – The optimal chromatographic conditions were achieved on a C18 column with gradient elution using 0.1% formic acid aqueous formic acid and acetonitrile at 235 nm. The selective HPLC method was validated for precision, linearity, limit of detection, limit of quantitation and accuracy.

Results – Deacetylasperulosidic acid (DAA) was found to be the major iridoid in noni fruit. In order of predominance, DAA concentrations in different parts of the noni plant were dried noni fruit > fruit juice > seed > flower > leaf > root. The order of predominance for asperulosidic acid (AA) concentration was dried noni fruit > leaf > flower > root > fruit juice > seed. DAA and AA contents of methanolic extracts of noni fruits collected from different tropical regions were 13.8–42.9 and 0.7–8.9 mg/g, respectively, with French Polynesia containing the highest total iridoids and the Dominican Republic containing the lowest.

Conclusion – Iridoids DAA and AA are found to be present in leaf, root, seed and flower of noni plants, and were identified as the major components in noni fruit. Given the great variation of iridoid contents in noni fruit grown in different tropical areas worldwide, geographical factors appear to have significant effects on fruit composition. The iridoids in noni fruit were stable at the temperatures used during pasteurisation and, therefore, may be useful marker compounds for identity and quality testing of commercial noni products. Copyright © 2010 John Wiley & Sons, Ltd.