bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, X‐ray Crystal Structures, and Solid‐State Fluorescence Properties of 5,5‐Dialkyl‐9‐dibutylamino‐5H‐benzo[b]naphtho[1,2‐d]furan‐6‐one and 3,3‐Dialkyl‐9‐dibutylamino‐3H‐benzo[kl]xanthen‐2‐one
Authors: Ooyama Yousuke , Hayashi Akiko , Okamoto Tomohiro , Egawa Haruka , Mamura Toshiki , Yoshida Katsuhira
Published: April 2008

Heterocyclic fluorophores 5,5‐dibutyl‐9‐dibutylamino‐5H‐benzo[b]naphtho[1,2‐d]furan‐6‐one (4) and 3,3‐dibutyl‐9‐dibutylamino‐3H‐benzo[kl]xanthen‐2‐one (7) with dialkyl substituents linked in a nonconjugated fashion to the chromophore skeleton have been derived from quinol‐type compounds 1 and 2, and their photophysical properties were investigated in solution and in the solid state. Fluorophores 4 and 7 exhibit strong fluorescence intensity in the solid‐state relative to that of quinols 1 and 2; however, 1 and 4 or 2 and 7 exhibit similar fluorescence intensities in solution. To elucidate the dramatic effect of the dialkyl substituent on the solid‐state fluorescence excitation and emission spectra, we performed semiempirical molecular orbital calculations (AM1 and INDO/S) and X‐ray crystallographic analysis. On the basis of the results of the calculations and the X‐ray crystal structures, the relation between the solid‐state photophysical properties and the chemical and crystal structures of 4 and 7 were discussed. It was confirmed that introduction of bulky dialkyl substituents to the fluorophore skeleton can efficiently prevent the short π–π contact between the fluorophores in molecular aggregation states and cause a dramatic solid‐state fluorescence enhancement. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Preparation of Alkyl and Aryl Chlorodifluoromethyl Ethers Using BrF3
Authors: Hagooly Youlia , Sasson Revital , Welch Michael J. , Rozen Shlomo
Published: April 2008

Both alkyl and aryl chlorothioformates could readily be obtained from the corresponding alcohols and thiophosgene. These families of compounds were treated with BrF3 to form the corresponding alkyl and aryl chlorodifluoromethyl ethers in 60–85 % yields. The method is suitable for constructing a variety of aliphatic as well as electron‐deficient aromatic chlorodifluoromethyl ethers. The reactions proceed under mild conditions and short reaction times. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
The family of fundamental social categories includes kinship: evidence from the memory confusion paradigm
Authors: Lieberman Debra , Oum Robert , Kurzban Robert
Published: April 2008

Kinship is a fundamental component of human sociality influencing a range of behaviors including altruism, aggression, and mating. Though a central focus in psychology's neighboring disciplines, kinship has been largely neglected within psychology. An illustrative example – and the focus here – is research on social categorization. Researchers investigating the categories into which our mind carves the social world have focused primarily on sex, age, and race. Here we present evidence that kinship belongs in the family of fundamental social categories. In a series of experiments using a memory confusion paradigm, we show that participants implicitly encode the kinship relations of social targets and do so to the same extent as sex and age, two previously established robust dimensions of social categorization. The functional framework applied here provides useful guide‐rails for investigating how the human mind naturally parses the social world, and, more broadly, helps unite psychology with its neighboring disciplines in which kinship is treated as an important conceptual tool. Copyright © 2008 John Wiley & Sons, Ltd.
A novel strategy for avian species identification by cytochromebgene
Authors: Lee James Chun‐I , Tsai Li‐Chin , Huang Mei‐Tzu , Jhuang Jhe‐An , Yao Cheng‐Te , Chin Shih‐Chien , Wang Lih‐Chiann , Linacre Adrian , Hsieh Hsing‐Mei
Published: April 2008

We report a DNA‐based test that can be applied to any avian species so that the amplicon can be used in species identification. The need for the test arose from the requirement to enforce the Wildlife Conservation Act in Taiwan where over 150 avian species are protected. It is difficult to enforce the law if no gross morphology is present and hence there is a requirement to develop a DNA test. This study uses a novel strategy for avian species identification by the cytochromebgene where a series of primer pairs producing amplicons of decreasing size was designed. The test is designed to produce the largest possible amplicon based upon the quality of the DNA in the sample. A total of 331 avian samples were tested representing 40 species. Sequencing of the amplicons revealed limited intraspecies variation and that no DNA sequence was shared by samples from two different avian species. The closest genetic distance among the 40 species was 0.059 which was betweenLonchura punctulataandEstrilda melpodabased upon data from the smallest amplicon. A DNA databank including 138 sequence types from 331 samples tested, representing 40 different species, was constructed in this study. A blind test was used to determine the value for this system for forensic applications that successfully identified the species.
Nasopharyngeal carcinoma—Review of the molecular mechanisms of tumorigenesis
Authors: Chou Josephine , Lin Yu‐Ching , Kim Jae , You Liang , Xu Zhidong , He Biao , Jablons David M.
Published: April 2008

Nasopharyngeal carcinoma (NPC) is a head and neck cancer rare throughout most of the world but common in certain geographic areas, such as southern Asia. While environmental factors and genetic susceptibility play important roles in NPC pathogenesis, the Epstein–Barr virus in particular has been implicated in the molecular abnormalities leading to NPC. There is upregulation of cellular proliferation pathways such as the Akt pathway, mitogen‐activated protein kinases, and the Wnt pathway. Cell adhesion is compromised due to abnormal E‐cadherin and β‐catenin function. Aberrations in cell cycle are due to dysregulation of factors such as p16, cyclin D1, and cyclin E. Anti‐apoptotic mechanisms are also upregulated. There are multiple abnormalities unique to NPC that are potential targets for novel treatments. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Hypopituitarism after radiotherapy for extracranial head and neck cancers
Authors: Bhandare Niranjan , Kennedy Laurence , Malyapa Robert S. , Morris Christopher G. , Mendenhall William M.
Published: April 2008

Background

The purpose of this study was to investigate the incidence of radiotherapy‐induced primary and secondary hypopituitarism.

Methods

Three hundred twelve patients treated with radiotherapy for extracranial head and neck tumors between 1964 and 2000 were evaluated. Radiotherapy doses to the hypothalamus and pituitary were estimated by reconstructing treatment plans.

Results

Clinical hypopituitarism was observed in 44 (14.1%) patients after a median interval of 5.6 years. Hypothalamic dysfunction was reported in 14 patients after a median interval of 4.4 years. Neither fractionation nor adjuvant chemotherapy significantly impacted clinical hypopituitarism on multivariate analysis, but total dose to the pituitary was significant (p= .0228). Twenty‐three of 68 (33.8%) patients tested for hypopituitarism demonstrated subclinical hypopituitarism. The 5‐ and 10‐year rates of freedom from clinical hypopituitarism were 93% and 72%. The 5‐ and 10‐year rates of freedom from subclinical hypopituitarism were 85% and 65%.

Conclusion

Clinical and subclinical manifestations of late radiation toxicity were observed in the hypothalamic‐pituitary axis. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Retroesophageal subclavian artery—Esophageal fistula: A rare complication of a salivary bypass tube
Authors: Inman Jared C. , Kim Paul , McHugh Richard
Published: April 2008

Salivary bypass tubes have been used with great success in preventing neck wound contamination from saliva and decreasing the risk of pharyngoesophageal stenosis. However, complications from esophageal tubes and risk factors for these complications should not be overlooked. Complications can be fatal, as demonstrated in this case of esophageal‐subclavian artery fistulization. Retroesophageal subclavian artery (RRESA) is 1 of the most common anatomical variations of the aortic system. Typically producing no symptoms, its discovery is usually coincidental. However, under the right circumstances, this artery can form a fistulous tract. This occurrence has also been documented in cases of long‐term nasogastric tube placement and incorrect use of “esophageal” stents. This unique case describes a 62‐year‐old man who suffered an arterioesophageal fistula during use of a Montgomery salivary bypass tube (MSBT)—a frequently used and exceptionally safe management tool in patients with head and neck cancer. © 2008 Wiley Periodicals, Inc. Head Neck, 2008
Absence of systems consolidation of fear memories after dorsal, ventral, or complete hippocampal damage
Authors: Sutherland Robert J. , O'Brien Jamus , Lehmann Hugo
Published: April 2008

We examined the effects of dorsal, ventral, or complete damage to the hippocampus on long‐term retention of a Pavlovian conditioned fear response to a tone and a context paired with foot shock. Rats received a fear conditioning episode, in which a tone and context or context‐alone were paired with foot shock. Two days or 12 weeks later, they received sham, dorsal, ventral, or complete NMDA‐induced damage of the hippocampus. During a retention test conducted 2 weeks after surgery, the sham control rats exhibited high levels of freezing in the context and in the presence of the tone. Rats with dorsal, ventral, or complete hippocampal damage displayed very little freezing in the context at either learning‐surgery intervals. Partial hippocampal damage tended to cause a smaller but consistent deficit in conditioned responding to context at the shorter (2 day) learning‐surgery interval. Rats with hippocampal damage did not display less severe retrograde amnesia for more remote (12 weeks) memories. A similar pattern of results was observed for freezing to the tone. We find that the severity of retrograde amnesia for fear conditioning is related to the extent of the damage and that there is consistent and severe retrograde amnesia for remote contextual and cued fear memories. These findings support the idea that the hippocampal formation plays an essential and possibly permanent role in fear memories. © 2008 Wiley‐Liss, Inc.
Aberrant dentate gyrus cytoarchitecture and fiber lamination in LIS1 mutant mice
Authors: Wang Yanling , Baraban Scott C.
Published: April 2008

Mutant mice with a heterozygous deletion of LIS1, show varying degrees of hippocampal abnormality and enhanced excitability. To examine how LIS1 affects cytoarchitecture and fiber lamination in dentate gyrus (DG), we performed a series of immunohistochemistry studies. By using different neuronal‐ and glial‐specific antibodies, we found that the majority of hippocampal cell populations were affected by heterozygous mutation of LIS1; some reelin‐positive Cajal‐Retzius cells were left undisturbed. Granule cell dispersion was significant in hippocampal sections from Lis1‐deficient mice. However, the fiber termination of commissural/associational fibers and mossy fibers appeared relatively compact despite obvious granule cell dispersion and CA1‐CA3 pyramidal cell disorganization. vGlut1‐immunoreactive axon terminals were found aberrantly traversing the dispersed granule cell layer. Consistent with previous observations, we also found that immature granule cells in Lis1 mutants, here stained with antibodies to doublecortin (DCX) and Mash‐1, are aberrantly located and bear an abnormal cellular morphology. Our findings suggest that LIS1 mutants exhibit abnormal cell positioning and aberrant hippocampal neurogenesis, but maintain relatively normal fiber termination patterns. The functional consequences of hippocampal granule cell dispersion could offer critical insight to the epileptic and cognitive disorder associated with LIS1 haploinsufficiency. © 2008 Wiley‐Liss, Inc.
Effect of tooth loss on spatial memory and trkB‐mRNA levels in rats
Authors: Yamazaki Kaoruko , Wakabayashi Noriyuki , Kobayashi Takuya , Suzuki Tetsuya
Published: April 2008

The mechanism by which tooth loss accelerates spatial memory impairment is unknown. The purpose of this study was to test the hypothesis that tooth loss affects trkB‐mRNA levels and leads to an accelerated decrease in the hippocampal cell density in rats. A radial maze was used to evaluate the spatial memory of male Wistar rats that were categorized based on the number of extracted molar teeth. Number of hippocampal pyramidal cells and the trkB‐mRNA expressions in the amygdala, perirhinal cortex, thalamus, and the hippocampal CA1, CA3, and CA4 areas, were evaluated using molecular biological techniques. Seven weeks after tooth extraction, maze performance was significantly lower in each tooth loss group than in the control group, and the number of extracted teeth was inversely proportional to the induction of the trkB‐mRNA and the hippocampal cell density. The average weight of rats increased by controlled feeding throughout the experiment without showing a significant difference between the control and experimental groups. The results indicated that, in rats, the spatial memory‐linked trkB‐mRNA was reduced in association with the tooth loss; this supports the hypothesis and suggests that teeth have a role in the prevention of spatial memory impairment. © 2008 Wiley‐Liss, Inc.
Exendin‐4 induction of Egr‐1 expression in INS‐1 β‐cells: Interaction of SRF, not YY1, with SRE site of rat Egr‐1 promoter
Authors: Kim Myung‐Jun , Kang Jung‐Hoon , Chang Seo‐Yoon , Jang Hyun‐Jong , Ryu Gyeong Ryul , Ko Seung Hyun , Jeong In‐Kyung , Kim Myung‐Suk , Jo Yang‐Hyeok
Published: April 2008

Glucagon‐like peptide‐1 (GLP‐1) induces several immediate early response genes such as c‐fos, c‐jun, and early growth response‐1 (Egr‐1), which are involved in cell proliferation and differentiation. We recently reported that exendin‐4 (EX‐4), a potent GLP‐1 agonist, upregulated Egr‐1 expression via phosphorylation of CREB, a transcription factor in INS‐1 β‐cells. This study was designed to investigate the role of another transcription factors, serum response factor (SRF) and Yin Yang‐1 (YY1), in EX‐4‐induced Egr‐1 expression. EX‐4 significantly increased Egr‐1 mRNA and subsequently its protein level. EX‐4‐induced Egr‐1 expression was inhibited by pretreatment with a PKA inhibitor, H‐89, and an MEK inhibitor, PD 98059. The siRNA‐mediated inhibition of PKA and ERK1 resulted in significant reduction of EX‐4‐induced Egr‐1 expression. Promoter analyses showed that SRE clusters were essential for Egr‐1 transcription, and YY1 overexpression did not affect Egr‐1 promoter activity. EMSA results demonstrated that EX‐4‐induced transient increase in DNA–protein complex on SRE site, and that both SRF and phospho‐SRF were bound to this site. Treatment of either YY1 consensus oligonucleotide or YY1 antibody did not effect the change of density or migration of the DNA–protein complex. Collectively, EX‐4‐induced Egr‐1 expression is largely dependent on cAMP‐mediated extracellular signal‐regulated kinase activation, and EX‐4 induces Egr‐1 transcription via the interaction of SRF and phospho‐SRF to SRE sites. J. Cell. Biochem. 104: 2261–2271, 2008. © 2008 Wiley‐Liss, Inc.
BMP signaling dynamics in embryonic orofacial tissue
Authors: Mukhopadhyay Partha , Webb Cynthia L. , Warner Dennis R. , Greene Robert M. , Pisano M. Michele
Published: April 2008

The bone morphogenetic protein (BMP) family represents a class of signaling molecules, that plays key roles in morphogenesis, cell proliferation, survival and differentiation during normal development. Members of this family are essential for the development of the mammalian orofacial region where they regulate cell proliferation, extracellular matrix synthesis, and cellular differentiation. Perturbation of any of these processes results in orofacial clefting. Embryonic orofacial tissue expresses BMP mRNAs, their cognate proteins, and BMP‐specific receptors in unique temporo‐spatial patterns, suggesting functional roles in orofacial development. However, specific genes that function as downstream mediators of BMP action during orofacial ontogenesis have not been well defined. In the current study, elements of the Smad component of the BMP intracellular signaling system were identified and characterized in embryonic orofacial tissue and functional activation of the Smad pathway by BMP2 and BMP4 was demonstrated. BMP2 and BMP4‐initiated Smad signaling in cells derived from embryonic orofacial tissue was found to result in: (1) phosphorylation of Smads 1 and 5; (2) nuclear translocation of Smads 1, 4, and 5; (3) binding of Smads 1, 4, and 5 to a consensus Smad binding element (SBE)‐containing oligonucleotide; (4) transactivation of transfected reporter constructs, containing BMP‐inducible Smad response elements; and (5) increased expression at transcriptional as well as translational levels of Id3 (endogenous gene containing BMP receptor‐specific Smad response elements). Collectively, these data document the existence of a functional Smad‐mediated BMP signaling system in cells of the developing murine orofacial region. J. Cell. Physiol. 216: 771–779, 2008, © 2008 Wiley‐Liss, Inc.
Two distinct amplification events of the c‐myc locus in a colorectal tumour
Authors: La Farina Mario , Bellavia Maurizio , Tagliavia Marcello , Eterno Vincenzo , Colomba Paolo , Scibetta Angelo , Albanese Ida
Published: April 2008

Southern hybridisation of genomic DNA extracted from a human primary colorectal carcinoma revealed amplification of a fragment containing the wild‐type c‐myc locus. Two additional rearranged DNA fragments, lying upstream of c‐myc, fused to distant non‐contiguous sequences from the same chromosome, with an opposite configuration (head to head vs. head to tail), were also found to be amplified. Sequences analysis suggested that these rearrangements resulted from illegitimate recombination at two distinct points within the DNA sequence just upstream of the c‐myc ORF and further that these events triggered two different amplification mechanisms, only one of which, involving a strand invasion event following DNA double strand breaks, increased the copy number of the c‐myc ORF. J. Cell. Physiol. 217: 34–39, 2008. © 2008 Wiley‐Liss, Inc.
Biomolecular characterization of human glioblastoma cells in primary cultures: Differentiating and antiangiogenic effects of natural and synthetic PPARγ agonists
Authors: Benedetti E. , Galzio R. , Cinque B. , Biordi L. , D'Amico M.A. , D'Angelo B. , Laurenti G. , Ricci A. , Festuccia C. , Cifone M.G. , Lombardi D. , Cimini A.
Published: April 2008

Gliomas are the most commonly diagnosed malignant brain primary tumors. Prognosis of patients with high‐grade gliomas is poor and scarcely affected by radiotherapy and chemotherapy. Several studies have reported antiproliferative and/or differentiating activities of some lipophylic molecules on glioblastoma cells. Some of these activities in cell signaling are mediated by a class of transcriptional factors referred to as peroxisome proliferator‐activated receptors (PPARs). PPARγ has been identified in transformed neural cells of human origin and it has been demonstrated that PPARγ agonists decrease cell proliferation, stimulate apoptosis and induce morphological changes and expression of markers typical of a more differentiated phenotype in glioblastoma and astrocytoma cell lines. These findings arise from studies mainly performed on long‐term cultured transformed cell lines. Such experimental models do not exactly reproduce the in vivo environment since long‐term culture often results in the accumulation of further molecular alterations in the cells. To be as close as possible to the in vivo condition, in the present work we investigated the effects of PPARγ natural and synthetic ligands on the biomolecular features of primary cultures of human glioblastoma cells derived from surgical specimens. We provide evidence that PPARγ agonists may interfere with glioblastoma growth and malignancy and might be taken in account as novel antitumoral drugs. J. Cell. Physiol. 217: 93–102, 2008. © 2008 Wiley‐Liss, Inc.
Fuel cell power generation from marine sediments: Investigation of cathode materials
Authors: Scott K , Cotlarciuc I , Head I , Katuri K P , Hall D , Lakeman J B , Browning D
Published: April 2008

BACKGROUND: Marine sediment microbial fuel cells (MFC) utilise oxidisable carbon compounds and other components present in sediments on ocean floors and similar environments to produce power in conjunction with, principally, oxygen reduction at the cathode in the overlying water. The aim of the work was to investigate a range of cathode materials for sediment MFC, to achieve relatively high levels of power.

RESULTS: Cell potential and power density performance data are reported for sediment MFC using cathodes of: carbon sponge, cloth and paper, graphite and reticulated vitreous carbon (RVC), Co and Fe‐Co tetramethoxyphenyl porphyrin (FeCoTMPP) and platinised carbon and titanium. The anode was graphite cloth. After a period of stabilisation, open circuit voltages of 700 mV and maximum power densities of 62 mW m−2 were obtained, using FeCoTMPP. Relatively low cost carbon cathodes gave power densities of around 30 mW m−2.

CONCLUSIONS: The study has shown that low level power can be produced from marine sediments using MFC without separators between the fuel and seawater containing dissolved oxygen. Cathode performance was an important factor determining the power output. Electrocatalyst at the cathode improved performance: FeCoTMMP gave power densities of 60 mW m−2 which was twice that achieved with the best un‐modified carbon. Copyright © 2008 Society of Chemical Industry
One‐step production of 2,3‐butanediol from starch by secretory over‐expression of amylase in Klebsiella pneumoniae
Authors: Zheng Yu , Zhang Haiyi , Zhao Li , Wei Liujing , Ma Xingyuan , Wei Dongzhi
Published: April 2008

BACKGROUND: 2,3‐Butanediol (2,3‐BD) is a valuable chemical that can be biosynthesized from many kinds of substrates. For commercial biological production of 2,3‐BD, it is desirable to use cheap substrate without pretreatment, such as starch. However, there have been few reports on the production of 2,3‐BD directly from starch.

RESULTS: In this work, gene malS coding for α‐amylase (EC 3.2.1.1) precursor was inserted into plasmid pUC18K, and secretory over‐expression of α‐amylase was achieved by engineered Klebsiella pneumoniae. The extracellular recombinant amylase accelerated the hydrolyzation of starch, and one‐step production of 2,3‐BD from starch was carried out by engineered K. pneumoniae. A 2,3‐BD concentration of 3.8 g L−1 and yield of 0.19 g 2,3‐BD g−1 starch were obtained after 24 h fermentation.

CONCLUSION: The one‐step production of 2,3‐BD from starch was achieved by secretory over‐expression of amylase in K. pneumoniae. This would simplify the process and reduce the production cost considerably by enabling use of starch with minimal pretreatment. Copyright © 2008 Society of Chemical Industry
An unusual case of a glomus tumor developing in a subcutaneous vein of the wrist
Authors: Koibuchi Harumi , Fujii Yasutomo , Taniguchi Nobuyuki
Published: April 2008

Glomus tumors are benign tumors that originate in a neuromyoarterial glomus body and most commonly occur in the subungual regions. We present an unusual case of a glomus tumor in a subcutaneous vein of the dorsum of the wrist in a 65‐year‐old man and describe its gray‐scale and power Doppler sonographic appearance, with a brief discussion of the clinical and histologic findings. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Evidence for a cross‐linking mechanism underlying glucose‐induced contraction of phenylboronate hydrogel
Authors: Pan Xiaohan , Yang Xiaoping , Lowe Christopher R.
Published: April 2008

The glucose‐dependent cross‐linking of phenylboronate gels was investigated in order to understand the principle underlying glucose‐induced hydrogel contraction. Glucose conformation upon binding to phenylboronates in aqueous solution was also examined and a 1:2 glucofuranose: boronate model was suggested by the results obtained. Copyright © 2008 John Wiley & Sons, Ltd.
Well width‐dependent electron Raman scattering in ZnS/CdSe cylindrical quantum dot quantum well
Authors: Zhong Qing‐Hu , Liu Cui‐Hong
Published: April 2008

Electron Raman scattering (ERS) is investigated in ZnS/CdSe cylindrical quantum dot quantum well (QDQW). The differential cross section (DCS) is calculated as a function of the scattering frequency and the sizes of QDQW. Single parabolic conduction and valence bands are assumed. Different scattering configurations are discussed and the selection rules for the processes are also studied. Singularities in the spectrum are found and interpreted. The ERS studied here can be used to provide direct information about the electron band structure of these systems. Copyright © 2008 John Wiley & Sons, Ltd.
The effect of irrigation level and harvest mechanization on virgin olive oil quality in a traditional rain‐fed ‘Souri’ olive orchard converted to irrigation
Authors: Dag Arnon , Ben‐Gal Alon , Yermiyahu Uri , Basheer Loai , Nir Yogev , Kerem Zohar
Published: April 2008

BACKGROUND: Olive trees are generally grown under rain‐fed conditions. Since yield response to application of water in the growing season may be considerable, irrigation is increasingly introduced to existing, mature orchards. An additional feature of modernization of olive cultivation is mechanical harvesting. To investigate the effect of irrigation level on the quality of virgin olive oil (VOO) produced from cv. Souri, six regimes, ranging from deficit to excess, were applied to trees in a mature, traditional orchard as it was converted to irrigation. Furthermore, in order to investigate the effect of damage incurred during harvest, oil quality of hand‐picked fruit was compared to that of mechanically harvested olives.

RESULTS: Data were collected from two consecutive growing seasons. Increased irrigation quantity increased the free acidity level of the oil and decreased the total phenol content of VOO, while the peroxide level of the oil was not affected. Oil of hand‐picked fruits had lower free acidity, higher polyphenol content and slightly lower peroxide level compared to the oil of mechanically harvested olives.

CONCLUSION: Fruits from irrigated trees demonstrated an apparent sensitivity to mechanical wounding that subsequently led to increased free acidity, increased peroxide level and decreased total phenol content in oil. Management of irrigated orchards including method and timing of harvest and oil extraction techniques should consider these results in order to optimize production of high‐quality oil. Copyright © 2008 Society of Chemical Industry
Investigation of interaction between human hemoglobin A0 and platinum anticancer drugs by capillary isoelectric focusing with whole column imaging detection
Authors: Lemma Tibebe , Mandal Rupasri , Li Xing‐Fang , Pawliszyn Janusz
Published: April 2008

CIEF with whole column imaging detection (WCID) was used to investigate the interaction of platinum‐based anticancer drugs, cis‐platinum(II) diamine dichloride (cisplatin) and [SP‐4‐2‐{1R‐trans)]‐(1,2‐cyclohexanediamine‐N,N′)[ethanedioata(2–)‐O,O′]platinum (oxaliplatin), with human hemoglobin A0 (Hb). This technique facilitates the investigation and characterization of the formation of adducts between drugs and proteins. Cisplatin and oxaliplatin were mixed with the target protein at different concentrations (0:1, 1:1, 1:10, 1:50, and 1:100), and the reaction mixtures were incubated for 0, 0.5, 1, 12, 24, 48, and 72 h at 37°C in a water‐bath. The focused Hb–drug adduct profiles were imaged by WCID. At higher drug to protein molar ratios (for both oxaliplatin and cisplatin), the results exhibit significant changes in the peak shapes and heights, which may indicate the destabilization of the protein. However, the conformational change was less evident at lower molar ratios. In addition, a major pI shift was observed for the oxaliplatin reaction mixtures (for 1:10, 1:50, and 1:100 ratios). In comparison with previously reported findings obtained by other analytical methods, conclusions were drawn about the validity of CIEF as a simple and convenient method for the investigation of protein–drug interactions. These results may provide useful information for further understanding the activity and toxicity of these chemotherapeutic drugs and improving their clinical performance.
A Novel Route for Polystyrene Grafted Single‐Walled Carbon Nanotubes and their Characterization
Authors: Nayak Rati Ranjan , Shanmugharaj Andikkadu M. , Ryu Sung Hun
Published: April 2008

A novel route to graft polystyrene from the surface of single walled carbon nanotubes has been discussed. Grafting of one styrene unit onto SWCNT sidewalls was successfully done by Friedel Craft acylation reaction using cheap and reusable ZnO catalyst. FT‐IR and Raman spectra and TGA show the effective grafting of styrene onto the SWCNT. End‐grafted polystyrene polymer was synthesized on the SWCNT surface by free radical polymerization. It is found that optimum monomer concentration, reaction temperature and time exist. NMR and FT‐IR spectroscopy confirm the grafting of polystyrene from the SWCNT surface. Little change in the nature of SWCNT is observed from Raman spectroscopy. Nanocomposite films prepared using polystyrene and functionalized carbon nanotubes exhibits low volume resistivity.

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Fabrication of Light‐Guiding Core/Sheath Fibers by Coaxial Electrospinning
Authors: Kwak Giseop , Lee Ga Hyoung , Shim Shang‐hun , Yoon Keun‐Byoung
Published: April 2008

Light‐guiding core/sheath fibers are fabricated from two different refractive index (RI) polymers by coaxial electrospinning. The morphology and fiber diameter are analyzed with scanning electron and fluorescence microscopies. It is found that the diameter of the core and the thickness of the sheath could be varied from 100 to 400 nm by changing the concentration of the outer solution. The incorporation of a chromophore into the inner material confirmed the uniformity of the core/sheath structure in long segments of the fibers. The boundary is clearly seen: the core diameter and the thickness of the sheath are constant along the fiber axis in fluorescence images. The ejected beam is circular and light‐guided along the fiber axis as in an optical fiber.

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Preconditioned gradient flows for nonlinear eigenvalue problems and application to the Hartree‐Fock functional
Authors: Alouges François , Audouze Christophe
Published: April 2008

In this article, we propose to solve numerically the problem of finding the smallest eigenvalues of a Hermitian operator (and the space spanned by the corresponding eigenvectors) by a gradient flow technique. This method is then applied to the Hartree‐Fock problem. Improvements are also proposed in two directions: preconditioning of the dynamical system and development of a specific flow that enables to compute directly the eigenvectors. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Effects of organic modifications of clay on the ultraviolet‐curing behavior and structure of a polyester‐acrylate/clay nanocomposite system
Authors: Kim Yong Hoon , Kim Dae Su
Published: April 2008

A pristine clay (Na+‐montmorillonite (MMT) and three different organoclays (20A‐MMT, vinylbenzyl dimethyldodecyl ammonium (VDA)‐MMT, and siloxane diamine ammonium (SDA)‐MMT) that originated from the pristine clay were used to prepare polyester‐acrylate (PEA)/clay nanocomposites by in situ ultraviolet (UV)‐curing. Except for the commercial organoclay (20A‐MMT), VDA‐MMT, and SDA‐MMT were prepared in this study by ion exchange method. The effects of organic modifications of the pristine clay on the UV‐curing behavior and structure of the nanocomposite system were investigated. The organic modifications of the clay affected considerably the UV‐curing behavior and structure of the nanocomposite system. Copyright © 2008 John Wiley & Sons, Ltd.
Polylactide (PLA) designed with desired end‐use properties: 1. PLA compositions with low molecular weight ester‐like plasticizers and related performances
Authors: Murariu Marius , Da Silva Ferreira Amália , Alexandre Michaël , Dubois Philippe
Published: April 2008

Polylactide (PLA) is an attractive candidate for replacing petrochemical polymers because it is biodegradable and produced from annually renewable resources. Characterized by high tensile strength, unfortunately the brittleness and rigidity of PLA limit its applicability. For a great number of applications such as packaging, fibers, films, etc., it is of high interest to formulate new grades with improved flexibility and better impact properties. In this objective, a specific PLA grade (L/D isomer ratio of 96:4, high molecular weight) was melt‐mixed with selected plasticizers: bis(2‐ethylhexyl) adipate (DOA), glyceryl triacetate (GTA), and tributyl O‐acetylcitrate (TBAC). Their effect on the molecular, thermal, and mechanical properties of PLA was investigated for content up to 20 wt% plasticizer and the results were correlated with a particular attention to the relationship between property and application. Using the solubility and interaction parameters, a tentative evaluation of the product that could act as the most effective plasticizer for PLA has been performed and the obtained results have been corroborated with the materials physical properties. Excellent mechanical performances were obtained using the plasticizer having the lowest molecular mass (GTA) and the best interaction parameter. In relation to plasticizer amount/nature, the glass transition temperature of PLA (62°C) is decreased by plasticizing by more than 30°C, whereas better impact properties and lower stiffness are measured. The optimal formulations targeted to the final applications are clearly characterized by specific end‐use properties: improved crystallization rates (PLA‐DOA); high elongation at break and tensile strength (PLA‐GTA, PLA‐TBAC), medium to high impact properties (PLA‐DOA, PLA‐GTA) compositions. Copyright © 2008 John Wiley & Sons, Ltd.
Luftverkehr und Klima. Atmosphärenforschung
Authors: Schumann, Ulrich
Published: April 2008

Der globale Luftverkehr hat zum bisherigen Klimawandel nicht nur durch Ausstoß von Kohlendioxid, sondern auch durch Zusatzeffekte aus Stickoxiden, Kondensstreifen und Veränderungen der Bewölkung beigetragen. An der Gesamtheit der von Menschen verursachten Klimaänderung ist der Luftverkehr bisher mit etwa 3 % (2 bis 8 %) beteiligt. Der Anteil der Zusatzeffekte hängt vom Wachstum des Flugverkehrs und der betrachten Zeitspanne in der Zukunft ab und kann nicht mit einem konstanten Faktor bewertet werden. Bei raschem Verkehrswachstum sind die Zusatzeffekte groß, bei langsamerem Wachstum und über lange Zeiträume dominiert das ausgestoßene Kohlendioxid die Klimawirkung des Luftverkehrs.
Solarzellen nach biologischem Vorbild?
Authors: Wörmke Stephan , Mackowski Sebastian , Scheer Hugo , Bräuchle Christoph
Published: April 2008

Forscher der LMU München haben gezeigt, dass sich mit Hilfe von Silbernanoteilchen die Effizienz von Lichtsammelkomplexen enorm steigern lässt. Da es sich hierbei um die zentralen Funktionsträger für das Einsammeln von Licht bei der Photosynthese handelt, könnte diese Entdeckung bedeutsam für die Entwicklung neuartiger Hybrid‐Solarzellen sein.
Teilchenbeschuss aus dem All
Authors: Heering Peter
Published: April 2008

Anfang des 20. Jahrhunderts wies der österreichische Physiker Victor Hess die von ihm so genannte Höhenstrahlung nach. Allerdings waren seine Ergebnisse zunächst umstritten. Erst mit den Untersuchungen der Forschungsgruppe Robert Millikans, der für diese Strahlung den Begriff cosmic rays etablierte, wurde dieses Phänomen allgemein akzeptiert. Bis heute spielt die Untersuchung der Höhenstrahlung eine wesentliche Rolle in der physikalischen Grundlagenforschung.
Enzymatischer Proteinleim
Authors: Vilgis Thomas
Published: April 2008

“Zu schade zum Wegwerfen” ist der Leitsatz in vielen Küchen und Lebensmittelunternehmen. Das gilt beispielsweise für hochwertige Fleischabschnitte, die in Würsten oder Pasteten verarbeitet werden. Derartige Fleischtrümmer können mit biologischer Klebetechnik wieder in Form gebracht werden. Das Enzym Transglutaminase leistet dabei katalytische Dienste und verklebt Fleischstücke, indem es deren Proteine permanent vernetzt. Wie funktioniert und was nützt uns das?
Identification of peptidases in Nicotiana tabacum leaf intercellular fluid
Authors: Delannoy Mélanie , Alves Georges , Vertommen Didier , Ma Julian , Boutry Marc , Navarre Catherine
Published: April 2008

Peptidases in the extracellular space might affect the integrity of recombinant proteins expressed in, and secreted from, plant cells. To identify extracellular peptidases, we recovered the leaf intercellular fluid from Nicotiana tabacum plants by an infiltration–centrifugation method. The activity of various peptidases was detected by an in vitro assay in the presence of specific inhibitors, using BSA and human serum γ‐globulin as substrates. Peptidases were detected by 1‐ and 2‐D zymography in a polyacrylamide gel containing gelatin as substrate. Proteolytic activity was observed over a wide range of molecular masses equal to, or higher than, 45 kDa. To identify the peptidases, the extracellular proteins were digested with trypsin and analyzed by LC and MS. Seventeen peptides showing identity or similarity to predicted plant aspartic, cysteine, and serine peptidases have been identified. The extracellular localization of a cysteine peptidase aleurain homolog was also shown.
Novel approaches to predict the retention of histidine‐containing peptides in immobilized metal‐affinity chromatography
Authors: Du Hongying , Zhang Xiaoyun , Wang Jie , Yao Xiaojun , Hu Zhide
Published: April 2008

The new method lazy learning method–local lazy regression (LLR) was first used to model the quantitative structure–retention relationship (QSRR) for predicting and explaining the retention behaviors of peptides in the nickel column in immobilized metal‐affinity chromatography (IMAC). The best multilinear regression (BMLR) method implemented in the CODESSA was used to select the most appropriate molecular descriptors from a large set and build a linear regression model. Based on the selected five descriptors, another two approaches, projection pursuit regression (PPR) and LLR were used to build more accurate QSRR models. The coefficients of determination (R2) of the best model developed based on LLR were 0.9446 and 0.9252 for the training set and the test set, respectively. By comparison, it was proved that the novel local learning method LLR was a very promising tool for QSRR modeling with excellent predictive capability for the prediction of imidazole concentration (IMC) values of histidine‐containing peptides in IMAC. It could be used in other chromatography research fields and that should facilitate the design and purification of peptides and proteins.
Déjà vu in proteomics. A hit parade of repeatedly identified differentially expressed proteins
Authors: Petrak Jiri , Ivanek Robert , Toman Ondrej , Cmejla Radek , Cmejlova Jana , Vyoral Daniel , Zivny Jan , Vulpe Christopher D.
Published: April 2008

After reading many 2‐DE‐based articles featuring lists of the differentially expressed proteins, one starts experiencing a disturbing déjà vu. The same proteins seem to predominate regardless of the experiment, tissue or species. To quantify the occurrence of individual differentially expressed proteins in 2‐DE experiment reports, we compiled the identities of differentially expressed proteins identified in human, mouse, and rat tissues published in three recent volumes of Proteomics and calculated the appearance of the most predominant proteins in the dataset. The most frequently identified protein is a highly abundant glycolytic enzyme enolase 1, differentially expressed in nearly every third experiment on both human and rodent tissues. Heat‐shock protein 27 (HSP27) and heat‐shock protein 60 (HSP60) were differentially expressed in about 30 percent of human and rodent samples, respectively. Considering protein families as units, keratins and peroxiredoxins are the most frequently identified molecules, with at least one member of the group being differentially expressed in about 40 percent of all experiments. We suggest that the frequent identification of these proteins must be considered in the interpretation of any 2‐DE studies. We consider if these commonly observed changes represent common cellular stress responses or are a reflection of the technical limitations of 2‐DE.
Phosphorylation of measles virus nucleoprotein upregulates the transcriptional activity of minigenomic RNA
Authors: Hagiwara Kyoji , Sato Hiroki , Inoue Yoshihisa , Watanabe Akira , Yoneda Misako , Ikeda Fusako , Fujita Kentaro , Fukuda Hiroyuki , Takamura Chizuko , Kozuka‐Hata Hiroko , Oyama Masaaki , Sugano Sumio , Ohmi Shinobu , Kai Chieko
Published: April 2008

We report the first identification of phosphorylation sites of the nucleoprotein (N) of the family Paramyxoviridae. The N protein is known to be the most abundant protein in infected cells; it constructs the N–RNA complex (nucleocapsid) and supports transcription and replication of viral genomic RNA. To determine the role of phosphorylation of the N protein, we expressed the N protein of the HL strain of measles virus (MV) in mammalian cells and purified the nucleocapsid. After separation of the C‐terminal region from the core region, phosphorylated amino acids were assayed using MALDI‐TOF/TOF and ESI‐Q‐TOF MS analyses. Two amino acids, S479 and S510, were shown to be phosphorylated by both methods of analysis. Metabolic labeling of the N protein with 32P demonstrated that these two sites are the major phosphorylated sites within the MV‐N protein. In transcriptional analysis using negative‐strand minigenomic RNA containing the ORF of the luciferase gene, mutants of each phosphorylation site showed approximately 80% reduction in luciferase activity compared with the wild‐type N, suggesting that the phosphorylation of N protein is important in the activation of the transcription of viral mRNA and/or replication of the genome in vivo.
Spectroscopic study of mono‐ and bis(styryl) dyes of the pyridinium series containing azathiacrown ether residue
Authors: Tulyakova E. V. , Fedorova O. A. , Fedorov Yu. V. , Jonusauskas G. , Anisimov A. V.
Published: April 2008

Phenylazathiacrown ether monostyryl and bis(styryl) dyes were synthesized and their complex forming ability was evaluated in acetonitrile by absorption and fluorescence spectroscopy. It was found that dyes are sensitive to the presence of H+ and Hg2+, Ag+, Cu2+ cations. The most stable complexes were formed with mercury. Stability constants and UV–Vis spectra of complexes defined stoichiometry were determined with the use of HYPERQUAD program. Evidence was given for the occurrence of two stoichiometries: LM and LM2. The pronounced optical response on complex formation was found both in absorption and emission spectra that could be used for optical detection of cations. Copyright © 2008 John Wiley & Sons, Ltd.
An exploratory study to investigate possible simple descriptors in order to predict relative activity of antiepileptic enaminones
Authors: Martinez J. C. Garro , Andrada M. F. , Estrada M. R. , Castro E. A. , Zamarbide G. N. , Mucsi Z. , Csizmadia I. G.
Published: April 2008

A general structure, substituent and activity relationship of the following type has been fitted to the available ED50 values of cyclic enaminone antiepileptic compounds: ${\rm ED}_{50} = f\left[ {{\rm structure,}\;{\rm substituent}} \right] = f[d, \sigma]$. In this relationship ‘structure’ was quantified by d, the distance measured between the carbonyl oxygen and the first atom of the aromatic ring. The ‘substituent’ was quantified by Hammett substituent constant: (σ). With the aid of the above function of two independent variables, a new molecular structure was predicted by extrapolation that has shown about two orders of magnitude greater activity than the most active molecule in the original set with measured ED50 values. Copyright © 2008 John Wiley & Sons, Ltd.
Quantitative approach to evaluate the intramolecular interaction of the appointed and unlinked groups or nonhydrogen atoms within organic compounds
Authors: Zhang Chaoyang
Published: April 2008

This paper reported a new approach to quantitatively evaluate the interaction of the appointed and indirectly linked groups or nonhydrogen atoms in molecules by designing unique isodesmic reactions, calculating their energy changes, and getting so‐called interaction energy (Ei). The consistency of the sign and amount of Ei with the common qualitative descriptions on some intramolecular effects confirmed the validity of the new method. Two applications of this method to halogenated methane and ethane, and nitro compounds showed: (1) for any group of molecules with the same skeleton, Ei of all substitution groups or nonhydrogen atoms can be used to compare their molecular stabilities; (2) for the appointed groups in different molecules, Ei of them can reveal the nature (attraction or repulsion) and the strength of their interaction. All these indicated that Ei is a useful tool to reflect the intramolecular interaction of appointed and unlinked groups or nonhydrogen atoms. Copyright © 2008 John Wiley & Sons, Ltd.
Charge transport and single‐electron effects in nanoscale systems
Authors: Thijssen J. M. , Van der Zant H. S. J.
Published: April 2008

In this review, we consider single‐electron effects in transport through nanoscale devices. These effects are ubiquitous in quantum dot physics, but in recent years their occurrence in molecular transport has triggered important new research efforts. In this case, the experimental results show a rich variety of features which make it possible to extract a wealth of information about the physics of these structures. We shall show that most of this information can be extracted in the case where the coupling of the active region to the leads is weak. However, between the strong and weak coupling regimes, that is, at intermediate coupling, we can observe the richest behaviour. We shall very briefly outline the physics of different transport processes through three‐terminal devices and then focus on the single‐electron effects. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical spectroscopy of single‐walledcarbon nanotubes: From excitonic effects towards control of the radiative lifetime
Authors: Pomraenke Robert , Vasa Parinda , Lienau Christoph
Published: April 2008

We have recently studied excitonic effects on the optical properties of single‐walled carbon nanotubes by means of two‐photon spectroscopy and time‐resolved photoluminescence spectroscopy. For nanotubes with diameters between 6.8 Å and 9.0 Å, the two‐photon spectra give evidence for large binding energies between 300 meV to 400 meV. Theoretical simulations of these spectra indicate that the lowest energy exciton state in nanotubes is an optically dark exciton, which has profound implications on the luminescence yield and exciton dynamics in single‐walled nanotubes. Indeed, time‐resolved photoluminescence measurements of individual nanotubes reveal low quantum yields and rather short exciton lifetimes ranging from 10 ps to 200 ps, which are affected by exciton relaxation between bright and dark states and non‐radiative exciton recombination. These results suggest that a control of the radiative lifetime of nanotube excitons may be a viable strategy for enhancing their luminescence yield. Here, we propose that exciton‐coupling to surface plasmon polaritons in metallic nanostructures may result in a substantial enhancement of the radiative exciton decay rate. Two‐photon luminescence excitation spectra of single‐walled carbon nanotubes. The luminescence intensity is plotted as a function of excitation and detection wavelength. The various two‐photon resonances are assigned to nanotube species with different chiral indices (n,m), as indicated in the figure. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)