bluuebunny/crossref_metadata_2025 huggingface dataset:
EXAMINING THE RELATIONSHIP BETWEEN PARENTS' GENDER ROLES AND RESPONSIBILITIES TOWARDS THEIR CHILDREN (A TURKISH EXAMPLE)
Authors: Erkal Sibel , Copur Zeynep , Dogan Nuri , Safak Sukran
Published: April 2009

This study was planned and conducted in order to determine parents' gender roles and their influence on children and their attitudes towards responsibility. The study involved 600 people (405 men, 195 women) selected through a random sampling method from a total of 3536 staff from
Hacettepe University. The instruments used in this study consisted of 4 parts: personal information survey, responsibility and satisfaction surveys, and the adapted Turkish version of the Bem Sex Role Inventory (BSRI). Two-way ANOVA (2 × 4 factorial design) methods were used for the
research questions. According to the results of the study, it is evident that mothers are more involved in childcare than fathers. However, gender roles, classified as “androgynous”, “masculine”, “feminine” and “undifferentiated”, do not seem
to have a significant effect on the amount of time a parent spends with his/her children.
Development of SMS Mobile Technology for M-Learning for Distance Learners
Authors: Ismail Issham Bin , M.Idrus Rozhan
Published: April 2009

The evolution of technologies as well as Internet application has created new ways of communication which gives impact to all regions and sectors including educators and learners in Higher-Education Learning institutions in Malaysia. Virtual learning environments as well as e-learning applications are some of pedagogical mechanisms which may sound easy and quick to be applied but unfortunately they are rarely used. This research attempts to introduce m-Learning as â??Convenience Education
Versatile Structure‐Directing Roles of Deep‐Eutectic Solvents and Their Implication in the Generation of Porosity and Open Metal Sites for Gas Storage
Authors: Zhang Jian , Wu Tao , Chen Shumei , Feng Pingyun , Bu Xianhui
Published: April 2009

Trap it in and burn it out: A deep‐eutectic solvent provides a versatile medium for the creation of highly stable porous frameworks encapsulating neutral coordinating ligand molecules, which can escape intact from the pores upon heating to form crystals directly, leaving behind permanent porosity and coordinatively unsaturated metal sites with potential applications in gas storage and catalysis.

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Superacidity of Boron Acids H2(B12X12) (X=Cl, Br)
Authors: Avelar Amy , Tham Fook S. , Reed Christopher A.
Published: April 2009

Acid remarks: The anhydrous diprotic boron acids H2(B12X12) (X=Cl, Br; see picture, B orange, X green) are the first examples of diprotic superacids and may be the strongest acids yet isolated. Both protons protonate benzene to give benzenium ion salts that are stable at room temperature. These acids owe their existence to the stability of the icosahedral B12 cluster with its dinegative charge buried beneath a layer of halide substituents.

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Negative air ion releasing properties of tourmaline/bamboo charcoal compounds containing ethylene propylene diene terpolymer/polypropylene composites
Authors: Yeh Jen‐Taut , Hsiung Han‐Hsing , Wei Wei , Zhu Ping , Chen Kan‐Nan , Jiang Tao
Published: April 2009

The average concentrations of negative air ions (Cion−) emitted from tourmaline (T), bamboo charcoal (B) particles, and tourmaline/bamboo charcoal (T/B) compounds containing polypropylene (PP) and ethylene propylene diene terpolymer/polypropylene (EPDM/PP) composite specimens under varying testing conditions were investigated in this study. The Cion− values emitted from T or B filled PP and EPDM/PP composite specimens reached a maximum value as their T or B contents approached the 5 and 3 wt % optimum values, respectively. In contrast, the Cion− values of T/B compounds filled PP and EPDM/PP composite specimens were significantly higher than their theoretical Cion− values estimated using the “simple mixing rule,” and reached a maximum value as the weight ratio of T to B reaches an optimum value. At this optimum T/B weight ratio, the Cion− values of T/B compounds filled PP and EPDM/PP composite specimens reached another maximum as their total compound loadings reached the optimum loading of 6 and 4 wt %, respectively. The Cion− values of the PP/T/B and EPDM/PP/T/B specimens increased significantly as they were tested under dynamic mode or by increasing the testing temperatures. The T and/or T/B powders filled PP and EPDM/PP specimens exhibited significantly higher tensile strength (σf) and elongation at break (εf) values than did the B filled PP and EPDM/PP specimens with the same filler loadings, respectively. Energy dispersive X‐rays, particle size, and SEM morphology analysis of the filler particles present in the T, B, and T/B filled composite specimens were performed to understand these interesting negative air ion and tensile properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Suspension polymerization of poly(methyl methacrylate)/clay nanocomposites
Authors: Clarke Nigel , Hutchings Lian R. , Robinson Ian , Elder Judith A. , Collins Stephen A.
Published: April 2009

Polymer/clay nanocomposites (PCNs) of poly(methyl methacrylate) and an organically modified clay, Cloisite 15a, were synthesized in situ with a suspension polymerization technique. The amount of clay present in the PCNs was varied to provide a better understanding of the effect of the clay on the properties of the polymer matrix. However, unexpectedly, we found that the concentration of clay had a dramatic impact on the molecular weight of the polymer matrix, and a relationship between the clay concentration and polymer molecular weight was determined. The PCNs were characterized with size exclusion chromatography (SEC), X‐ray diffraction, transmission electron microscopy, and oscillatory shear rheology. From oscillatory shear rheology, the full master curves for the PCNs were obtained by application of the time–temperature superposition principle. To enable the effect of the clay on the rheology to be quantified, the experimental data was compared to the time‐dependent diffusion model of des Cloizeaux for polydisperse polymer melts, which enabled the polydispersity to be incorporated through the use of the molecular weight distribution obtained via SEC. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Application of Heteropolyacids as Heterogeneous and Recyclable Catalysts for One‐Pot Synthesis of 3‐Cyanopyridine Derivatives
Authors: HERAVI Majid M. , BEHESHTIA Yahya S. , KHORSHIDI Maliheh , BAGHERNEJAD Bita , BAMOHARRAM Fatemeh F.
Published: April 2009

A simple, clean and environmentally benign route to the synthesis of 3‐cyanopyridines is described via a one‐pot multi‐component reaction of 3,4‐dimethoxyacetophenone, malonitrile or ethylcyanoacetate, aldehyde and ammonium acetate using heteropolyacids as heterogeneous and recyclable catalysts in very good yields.
Dehydration of Oximes to Nitriles Catalyzed by a Green Heteropolyacid Catalyst: Preyssler's Anion, [NaP5W30O110]14−
Authors: HERAVI Majid M. , SADJADI Sodeh , HEKMATSHOAR Rahim , OSKOOIE Hossein A. , BAMOHARRAM Fatemeh F.
Published: April 2009

A mild, simple and high yielding procedure for the direct conversion of oximes to nitriles has been developed using heteropolyacid in acetic acid. Aromatic and aliphatic aldoximes were converted to the corresponding nitriles in the presence of Preyssler type heteropolyacid, which could be reused several times without any appreciable loss of activity.
Characteristics of black treatment seekers for eating disorders
Authors: Fernandes Nisha H. , Crow Scott J. , Thuras Paul , Peterson Carol B.
Published: April 2009

Objective:

This study sought to investigate differences in eating psychopathology between black and white treatment seekers at a specialty eating disorders (EDs) center.

Method:

Participants were drawn from 1680 individuals (n = 32 blacks; n = 1648 whites) who received treatment for an ED at a specialized center between 1979 and 1995, and had completed the EDs Questionnaire. The 32 black participants were matched to 153 white participants for ED diagnosis, year of presentation, and gender.

Results:

The majority of the participants were diagnosed with eating disorder not otherwise specified (EDNOS). No black participants met criteria for anorexia nervosa (AN). Black participants reported more body dissatisfaction and a higher percentage fulfilled the obesity criterion compared to white participants. There were few differences in reported history of previous treatment.

Discussion:

Black and white participants with EDs appeared similar in most respects, but AN was notably absent among black participants. In contrast to previous research, body dissatisfaction was surprisingly higher in black than in white participants. © 2009 by Wiley Periodicals, Inc. Int J Eat Disord 2010
Mercuric ion‐catalyzed hydration of derivatives of 1,4‐dichloro‐2‐butyne. Hydration of 1‐aryloxy‐4‐arylthio‐2‐butynes, 1,4‐bis(arylthio)‐2‐butynes, and 1,4‐bis(arylsulfonyl)‐1‐butynes
Authors: Thyagarajan B. S. , Majumdar K. C. , Bates Dallas K.
Published: April 2009

The mercuric ion‐catalyzed hydration of 1,4‐bis(arylthio)‐2‐butynes and 1‐aryloxy‐4‐arylthio‐2‐butynes was studied. The 1,4‐bis(arylsulfonyl)‐2‐butynes afforded 1,4‐bis(arylsulfonyl)‐2‐butanones (7). The 1,4‐bis(arylthio)‐2‐butynes afforded a variety of products in acetic acid among which were: 1,4‐bis(arylthiomethyl)vinyl acetate (18); 1,4‐bis(arylthio)‐2‐butanone (15); 1‐(arylthio)‐3‐buten‐2‐one (16); and 1‐(arylthio)‐4‐acetoxy‐2‐butanone (17). Ketone 15 eliminates arylthiol in an acidic medium yielding 16 which undergoes Michael addition of solvent to give 17. Treatment of 7 with base in the presence of a nucleophile (ArSH) analogously leads to elimination of arylsulfinic acid, followed by Michael addition of arylthiol. Hydration of 5 in methanol cleanly gave 1‐(arylthio)‐4‐methoxy‐2‐butanones (19). In contrast, 1‐aryloxy‐4‐arylthio‐24)utynes afforded chromenes (8) by intramolecular cyclization. No thiochromenes were formed in any of the examples investigated.
Triazolines VIII. Action of diazoalkanes on heterocyclic substituted schiff bases
Authors: Kadaba Pankaja K.
Published: April 2009

Diazoalkanes have been found to add to heterocyclic substituted Schiff bases (imines), providing a very useful route to the synthesis of the hitherto unknown heterocyclic substituted Δ‐1,2,3‐triazolines. The orientation of the addition as well as the results of synthesis accord with previously reported mechanistic considerations. The direction of dipole orientation and the structure assigned to the adducts are elucidated by nmr spectroscopy.
Cyclization of ylidenemalononitriles. VIII. Synthesis of coumarins from o‐methoxybenzylidenemalonitriles
Authors: Campaigne E. , Mais Dale E.
Published: April 2009

A new synthesis of coumarins, by direct cyclization of α‐cyano‐o‐methoxycinnamates in sulfuric acid, is described. The reaction seems quite general, and alkoxy groups other than the o‐methoxy group involved in lactone formation are not hydrolyzed during the reaction. The 3‐cyano group on the resulting coumarin is not hydrated in concentrated sulfuric acid, but can be converted to the carbamido group in 90% sulfuric acid. In certain cases these conditions do cleave methoxy substituents on the coumarins. Although the sulfuric acid cyclization did not produce the usual indenones when an o‐methoxy group was present, the corresponding indenones could be obtained by cyclizing the ylidenemalononitriles with boron trifluoride‐etherate. Possible reasons for this selectivity are discussed, and new coumarins and indenones characterized.
Tautomerism in malonic ester derivatives of s‐triazine
Authors: Reynolds C. Fredric , Saari Arthur F.
Published: April 2009

Pmr and uv spectra of tris‐, bis‐ and monomalonic ester derivatives of s‐triazine were studied in chloroform, dioxane, methanol, water, acetonitrile, dimethylsulfoxide, dimethylformamide, and cyclohexylamine. The results indicate that the enaminic structures (I, II and III) predominate in chloroform, dioxane, methanol and water. A small amount of enolate is present in acetonitrile and a larger amount of enolate is present in dimethylsulfoxide, dimethylformamide and cyclohexylamine in the case of the tris‐ and bismalonic ester derivatives of s‐triazine. The conclusion is reached that for these latter compounds in basic solvent, a tautomeric equilibrium exists between the enaminic form and resonance‐stabilized enolate ions.
The synthesis of some substituted tetraarylporphyrins
Authors: Little Robert G. , Anton John A. , Loach Paul A. , Ibers James A.
Published: April 2009

The synthesis of six unsymmetrically substituted tetraarylporphyrins is reported. The compounds prepared are 5‐(R),10,15,20‐tritolylporphyrins, where R = 2‐pyridyl, 3‐pyridyl, 4‐acet‐amido, and 2,3 or 4‐hydroxyphenyl. Four new tetrasubstituted tetraarylporphyrins (5,10,15,20‐tetra‐(R)‐porphyrin) are also reported, where R = 3‐pyridyl, 4‐acetylphenyl, 4‐hydroxyphenyl and 4‐butoxyphenyl. The proton nmr spectra of these porphyrins are presented.
Synthesis of 5,6,7‐trimethylbenz[c]acridine
Authors: Pokorny D. J. , Fischer D. L. , Nielsen L. A. , George A. Denise , Cromwell N. H.
Published: April 2009

A new potential carcinogenic aromatic heterocyclic compound, 5,6,7‐trimethylbenz[c]acridine (1), has been synthesized from the known 5,5‐dimethyl‐6‐keto‐5,6‐dihydrobenz[c]acridine (4) using a series of reactions which includes an interesting new type of 1,4‐conjugate addition cmploying lithium dimethylcopper.
The molecular structure and chemical reactivities of the condensation products of o‐substituted benzylidenacetylacetone with hydrazine dihydrochloride
Authors: Kurihara Takushi , Sugiyama Mariko , Hirano Hiroshi , Tomita Ken‐Ichi , Sakaki Masayoshi
Published: April 2009

Reaction of o‐nitrobenzylideneacetylacetone (1a) with hydrazine dihydrochloride in methanol gave 4‐(α‐methoxy‐o‐nitrobenzyl)‐3,5‐dimethylpyrazole hydrochloride (4a), whose structure was unambigously confirmed by an X‐ray crystallographic analysis, via 4‐(o‐nitrobenzylidene)‐3,5‐dimethylisopyrazole (2a). Compound 2a was synthesized by condensation of 1a with hydrazine dihydrochloride in acetonitrile. Analogously the corresponding o‐chloro derivatives (2b, 4b) were obtained. These were converted to N‐methyl (6b) and N‐acetyl (7a,b) derivatives and the behaviors on bromination and pyrolysis were investigated.
Synthesis of potential antineoplastic agents. XXV. Approaches to the pyridocarbazole system
Authors: Winchester Merrill J. , Popp Frank D.
Published: April 2009

The indolization of cyanomethylphenylhydrazines provides a convenient route to cyanomethylcarbazoles. These cyanomethylcarbazoles provide an important entry to the pyridocarbazole system including ellipticine.
Streptonigrin and related compounds. I. Some 2‐phenyl‐ and 2,2‐pyridylquinoline‐5,8‐diones
Authors: Rao Koppaka V.
Published: April 2009

Methods for the synthesis of 6‐amino‐7‐methoxy‐ and 7‐amino‐6‐methoxy‐2,2‐pyridylquinoline‐ 5,8‐diones and the corresponding 2‐phenylquinoline‐5,8‐diones are described. The 6‐aminoquinone system was generated by direct amination with sodium azide and the 7‐aminoquinone system via the novel 6‐hydroxy‐7‐nitroquinone intermediates. The basic skeleton was derived by the application of the Friedlander quinoline synthesis.
14H‐Naphtho[1′,2′:5,6] pyrano[2,3‐b]quinoline derivatives
Authors: Roma Giorgio , Ermili Aldo , Balbi Alessandro
Published: April 2009

Reaction of (N‐alkyl‐N‐phenyl)ethoxycarbonylacetamides with β‐naphthol in the presence of phosphorus oxychloride afforded 1‐oxo‐3‐(N‐alkyl‐N‐phenyl)amino‐1H‐naphtho[2,1‐b]pyrans. These compounds underwent reaction with N,N‐dimethylformamide‐phosphorus oxychloride at 95° yielding a mixture of 14H‐naphtho[1′,2′:5,6]pyrano[2,3‐b]quinoline derivatives and 1‐oxo‐2‐formyl‐3‐(N‐alkyl‐N‐phenyl)amino‐9‐oxy‐1H‐phenalene. When the same reaction was performed at 140°, only 14‐oxo‐14H‐naphtho[1′,2′:5,6]pyrano[2,3‐b]quinoline was obtained in a very good yield. The structures of such compounds were demonstrated by spectral data and by chemical transformations. On the other hand, the expected formylation in the 2 position was achieved when 1‐oxo‐3‐(N‐alkyl‐N‐benzyl)amino‐1H‐naphtho[2,1‐b]pyrans reacted with N,N‐dimethylformamide‐phosphorus oxychloride.
Phospholes. The aromaticity problem
Authors: Hughes Alan N. , Kleemola Daniel
Published: April 2009

Newer techniques of phosphole synthesis, particularly those which lead to simple phospholes substituted with active functional groups, are briefly surveyed. A detailed account of chemical, physico‐chemical, spectroscopic and theoretical studies related to the phosphole aromaticity problem is given and the present conflicting position is discussed.
An improved synthesis of norcocaine
Authors: Stenberg V. I. , Narain N. K. , Singh S. P. , Parmar S. S.
Published: April 2009

An improved, high yielding procedure for the preparation of norcocaine from cocaine is described. The synthesis is accomplished by controlling the pH during the potassium permanganate oxidation. A quantitative conversion of N‐benzoylecgonine methyl ester into norcocaine by dry, hydrogen chloride‐dioxane is also included.
Synthesis of indolines from N‐allylarylamines
Authors: Krowicki Krzysztof , Paillous Nicole , Rivière Monique , Lattes Armand
Published: April 2009

A novel method of synthesis of nitrogen heterocycles is described. The acidic rearrangement of N‐allylanilines gives 2‐allylanilines which lead to indolines by photocyclization.
Improved syntheses of 5‐substituted‐4‐amino‐3‐mercapto‐(4H)‐1,2,4‐triazoles
Authors: Reid Jack R. , Heindel Ned D.
Published: April 2009

Two improved methods have been developed for the synthesis of 5‐substiluted‐4‐amino‐3‐mercapto‐(4H)‐1,2,4‐triazoles. One of these involves the direct hydrazinolysis of potassium 3‐aroyldithiocarbazates and the other involves ring‐opening and reclosure of 5‐substituted‐2‐mereapto‐1,3,4‐oxadiazoles to the aminomercaptotriazoles. Both of these methods offer advantages over the classic Hoggarth synthesis.
The sodium borohydrirle reduction of N‐iminopyridinium ylides. I. Synthesis of N‐imino‐1,2,3,6‐tetrahydropyridines
Authors: Knaus E. E. , Redda K.
Published: April 2009

Reaction of arylsulfonyl, pyridylearbonyl and arylalkylhydrazines 2 with 2,4‐dinitrophenyl‐pyridinium chloride 1 affords N‐iminopyridinium ylides 3. The sodium borohydride reduction of ylides 3 to N‐imino‐1,2,3,6‐tetrahydropyridines is described.
Synthesis of fused ring 1,2,4‐triazoles by intramolecular cycloaddition of nitrile imines to the nitrile function
Authors: Garanti Luisa , Scandroglio Angelo , Zecchi Gaetano
Published: April 2009

Treatment of 1‐chlorohydrazones (IIa‐c) with triethylamine gave fused ring 1,2,4‐triazoles arising from an intramolecular cycloaddition of the intermediate nitrile imines (IIIa‐c). This reaction was not observed in the case of one compound (IId) bearing an unactivated nitrile group.
Manganese efficiency and maganese‐uptake kinetics of raya (Brassica juncea), wheat (Triticum aestivum), and oat (Avena sativa) grown in nutrient solution and soil
Authors: Hassan Sayyari‐Zahan Mohammad , Singh Sadana Upkar , Steingrobe Bernd , Claassen Norbert
Published: April 2009

Manganese (Mn) deficiency is reported worldwide and often decreases crop yield. However, plant species differ in their susceptibility to Mn deficiency. Poaceae are often inefficient, whereas Brassicaceae seem to be efficient in Mn uptake. The objective of this paper was to determine the relevance of Mn‐uptake kinetics, root‐system size, and Mn mobilization for differences in Mn efficiency of wheat, oat, and raya. To determine Mn‐uptake kinetics, wheat (Triticum aestivum L. cv. PBW 343), raya (Brassica juncea L. cv. RLM 619), and oat (Avena sativa L. cv. Aragon) were grown in a growth chamber together in complete nutrient solution having an average Mn concentration of 90, 180, 360, 910, and 2270 nmol L–1. For determining Mn efficiency of the three species in soil, the plants were grown for 22 d in pots filled with 3 kg of a loamy soil low in Mn availability (pH (CaCl2) 7.4; DTPA‐extractable Mn: 3.5 mg (kg soil)–1). The soil was fertilized with 0, 1, 2, 4, and 8 mmol Mn (kg soil)–1 resulting in Mn soil‐solution concentrations ranging from 40 to 90 nmol L–1, hence lower than in the solution experiment. In order to determine Mn soil‐solution concentration close to the root surface, the root length density was increased by growing two plants of raya and four plants of wheat in only 250 mL soil columns for 25 d. In solution culture at high concentrations, raya showed a higher Mn uptake compared to wheat and oat. However, at low Mn supply, all three species were comparably Mn‐efficient, i.e., plant growth was similar, and also the uptake was similar. In soil, the highest yield was achieved for raya in the unfertilized treatment whereas the Poaceae needed at least a fertilization of 1 mmol Mn (kg soil)–1. The Poaceae showed a yield reduction of about 40% in the unfertilized treatment. Manganese concentration in the shoot dry weight was always higher in raya than in wheat or oat. This was due to a higher Mn uptake whereas relative shoot‐growth rate and root‐to‐shoot ratio were similar among the species. The higher Mn uptake of raya in soil was in contradiction to the comparable Mn‐uptake kinetics of the three crops at low Mn concentration in solution. This points to plant differences in their ability to affect Mn availability in the rhizosphere. In the bulk soil, all the crops decreased Mn solution concentration, but this effect was somewhat less for raya. But in the rhizosphere, raya increased Mn soil‐solution concentration significantly to 58 nmol L–1, as compared to 37 nmol L–1 of the unplanted control soil. In contrast, wheat showed a Mn solution concentration of 25 nmol L–1 which was not significantly different from the control. The results indicate that differences in Mn efficiency among the crops studied are related to their ability to affect the solubility of Mn in the rhizosphere.
The dynamics of gene products fluctuation during bovine pre‐hatching development
Authors: Gilbert Isabelle , Scantland Sara , Sylvestre Eve‐Lyne , Gravel Catherine , Laflamme Isabelle , Sirard Marc‐André , Robert Claude
Published: April 2009

Early embryonic development, spanning fertilization to blastocyst hatching, is a very dynamic developmental window that is characterized, especially in large mammals, by a period of transcriptional incompetence that ends during the maternal to embryonic transition (MET). Prior to the MET, the first cell cycles are supported by stored RNA and proteins pools accumulated during oogenesis. Therefore, RNA and protein content are different between developmental stages. It is also known that the stability of the stored mRNA and the mechanisms for translation recruitment are partly controlled by the length of the poly(A) tail. To date, little is known about RNA and protein content fluctuations during the pre‐hatching period. In this report we present measurements of total RNA, mRNA, poly(A) bearing mRNA and protein contents, as well as estimations of the proportions of both mRNA fractions to total RNA contents within these developmental stages. We found that while the ontogenic profiles of the different transcript contents were expected, their amounts were considerably lower than the reported values. Additionally, low 28S rRNA abundance and a tendency for diminishing protein content prior to the MET, suggest a limited potential for ribosomal turnover and translation. We consider the overall fluctuations in RNA and protein contents to be reference points that are essential for downstream interpretation of gene expression data across stages whether it be through candidates or high throughput approaches. Mol. Reprod. Dev. 76: 762–772, 2009. © 2009 Wiley‐Liss, Inc.
Dual crosslinked pH‐ and temperature‐sensitive hydrogel beads for intestine‐targeted controlled release
Authors: Ma Liwei , Liu Mingzhu , Liu Hongliang , Chen Jun , Gao Chunmei , Cui Dapeng
Published: April 2009

Novel drug‐loaded hydrogel beads for intestine‐targeted controlled release were developed by using pH‐ and temperature‐sensitive carboxymethyl chitosan‐graft‐poly(N,N‐diethylacrylamide) (CMCTS‐g‐PDEA) hydrogel as carriers and vitamin B2 (VB2) as a model drug. The hydrogel beads were prepared based on Ca2+ ionic crosslinking in acidic solution and formed dual crosslinked network structure. The structure of hydrogel and morphology of drug‐loaded beads were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). The study about swelling characteristics of hydrogel beads indicated that the beads had obvious pH‐ and temperature‐sensitivity. In vitro release studies of drug‐loaded beads were carried out in pH 1.2 HCl buffer solution and pH 7.4 phosphate buffer solution at 37°C, respectively. The results indicated that the dual crosslinked method could effectively control the drug release rate under gastrointestinal tract (GIT) conditions, which was superior to traditional single crosslinked beads. In addition, the effects of grafting percentage, pH value, and temperature on the release behavior of the VB2 were investigated. The drug release mechanism of CMCTS‐g‐PDEA drug‐loaded beads was analyzed by Peppa's potential equation. According to this study, the dual crosslinked hydrogel beads based on CMCTS‐g‐PDEA could serve as suitable candidate for drug site‐specific carrier in intestine. Copyright © 2009 John Wiley & Sons, Ltd.
Proteomic and selected metabolite analysis of grape berry tissues under well‐watered and water‐deficit stress conditions
Authors: Grimplet Jérôme , Wheatley Matthew D. , Jouira Hatem Ben , Deluc Laurent G. , Cramer Grant R. , Cushman John C.
Published: April 2009

In order to investigate the unique contribution of individual wine grape (Vitis vinifera) berry tissues and water‐deficit to wine quality traits, a survey of tissue‐specific differences in protein and selected metabolites was conducted using pericarp (skin and pulp) and seeds of berries from vines grown under well‐watered and water‐deficit stress conditions. Of 1047 proteins surveyed from pericarp by 2‐D PAGE, 90 identified proteins showed differential expression between the skin and pulp. Of 695 proteins surveyed from seed tissue, 163 were identified and revealed that the seed and pericarp proteomes were nearly completely distinct from one another. Water‐deficit stress altered the abundance of approximately 7% of pericarp proteins, but had little effect on seed protein expression. Comparison of protein and available mRNA expression patterns showed that 32% pericarp and 69% seed proteins exhibited similar quantitative expression patterns indicating that protein accumulation patterns are strongly influenced by post‐transcriptional processes. About half of the 32 metabolites surveyed showed tissue‐specific differences in abundance with water‐deficit stress affecting the accumulation of seven of these compounds. These results provide novel insights into the likely tissue‐specific origins and the influence of water‐deficit stress on the accumulation of key flavor and aroma compounds in wine.
Proteome mapping of the Drosophila melanogaster male reproductive system
Authors: Takemori Nobuaki , Yamamoto Masa‐Toshi
Published: April 2009

The fruit fly Drosophila melanogaster is an excellent model organism for studying insect reproductive biology. Although the gene expression profiles of both male and female reproductive organs have been studied in detail, their proteomic profiles and functional characteristics largely remained to be clarified. In this study, we conducted proteome mapping of the male internal reproductive organs using 2‐DE. We identified a total of 440 protein components from gels of the male reproductive organs (testis, seminal vesicle, accessory gland, ejaculatory duct, and ejaculatory bulb). A number of proteins associated with odorant/pheromone‐binding, lipid metabolism, proteolysis, and antioxidation were expressed tissue specifically in the male reproductive system. Based on our proteomic data set, we constructed reference proteome maps of the reproductive organs, which will provide valuable information toward a comprehensive understanding of Drosophila reproduction.
Automatic guidance of a four‐wheel‐steering mobile robot for accurate field operations
Authors: Cariou Christophe , Lenain Roland , Thuilot Benoit , Berducat Michel
Published: April 2009

As world population growth requires an increasing level of farm production at the same time that environmental preservation is a priority, the development of new agricultural tools and methods is required. In this framework, the development of robotic devices can provide an attractive solution, particularly in the field of autonomous vehicles. Accurate automatic guidance of mobile robots in farming constitutes a challenging problem for researchers, mainly due to the low grip conditions usually found in such a context. From assisted‐steering systems to agricultural robotics, numerous control algorithms have been studied to achieve high‐precision path tracking and have reached an accuracy within ±10 cm, whatever the ground configuration and the path to be followed. However, most existing approaches consider classical two‐wheel‐steering vehicles. Unfortunately, by using such a steering system, only the lateral deviation with respect to the path to be followed can be satisfactorily controlled. Indeed, the heading of the vehicle remains dependent on the grip conditions, and crabwise motions, for example, are systematically observed on a slippery slope, leading to inaccurate field operations. To tackle this drawback, a four‐wheel‐steering (4WS) mobile robot is considered, enabling servo of both lateral and angular deviations with respect to a desired trajectory. The path tracking control is designed using an extended kinematic representation, allowing account to be taken online of wheel skidding, while a backstepping approach permits management of the 4WS structure. The result is an approach taking advantage of both rear and front steering actuations to fully compensate for sliding effects during path tracking. Moreover, a predictive algorithm is developed in order to address delays induced by steering actuators, compensating for transient overshoots in curves. Experimental results demonstrate that despite sliding phenomena, the mobile robot is able to automatically and accurately achieve a desired path, with lateral and angular errors, respectively, within ±10 cm and ±2 deg, whatever its shape and whatever the terrain conditions. This constitutes a promising result in efforts to define efficient tools with which to tackle tomorrow's agriculture challenge. © 2009 Wiley Periodicals, Inc.
Surgical Diseases of the Womb According to Aetius of Amida (6th Century a.d.)
Authors: Lazaris Dimitrios P. , Laskaratos Faidon J. , Lascaratos Gerassimos J.
Published: April 2009

Background

In the interest of presenting historical background for modern‐day medicine and surgery, the authors comment on the concepts of the eminent Byzantine physician Aetius of Amida (sixth century a.d.) in surgical treatment of diseases of the womb.

Study design

The 16th book of Aetius’ work Tetrabiblus, in the original Greek language, a treatise on gynecology and obstetrics of his era, was investigated. Comparison was then made of the relative knowledge among ancient and Byzantine physicians.

Discussion

Aetius analytically describes many surgical diseases of the womb (prolapse, abscesses, phimosis, atresia, hemorrhoids, stones, thymos, chaps) and gives a detailed symptomatology and conservative and surgical treatment. His work followed Hippocratic, Roman, and early Byzantine physicians, especially Soranus, the “Father of ancient gynecology and obstetrics” and influenced later physicians of his era and beyond.

Conclusions

Aetius of Amida gives significant information about surgical approaches to diseases of the womb, the most detailed of any medical writer of his epoch. His descriptions, following the Hippocratic and mainly the Hellenistic and Roman traditions, influenced Islamic and European medicine, and through them the rest of the world, constituting the roots of the specialty of gynecology.
Solution structure of DnaE intein from Nostoc punctiforme: Structural basis for the design of a new split intein suitable for site‐specific chemical modification
Authors: Oeemig Jesper S. , Aranko A. Sesilja , Djupsjöbacka Janica , Heinämäki Kimmo , Iwaï Hideo
Published: April 2009

Naturally split DnaE intein from Nostoc punctiforme (Npu) has robust protein trans‐splicing activity and high tolerance of sequence variations at the splicing junctions. We determined the solution structure of a single chain variant of NpuDnaE intein by NMR spectroscopy. Based on the NMR structure and the backbone dynamics of the single chain NpuDnaE intein, we designed a functional split variant of the NpuDnaE intein having a short C‐terminal half (C‐intein) composed of six residues. In vivo and in vitro protein ligation of model proteins by the newly designed split intein were demonstrated.
Prospective, sequential, longitudinal study of coagulation changes during pregnancy in Chinese women
Authors: Liu Xing‐hui , Jiang Yong‐mei , Shi Hua , Yue Xin‐ai , Wang Yue‐fang , Yang Hui
Published: April 2009

Objective

To investigate changes and establish reference values for coagulation variables during normal pregnancy and after delivery in Chinese women.

Methods

A prospective, sequential, longitudinal study with strict inclusion and exclusion criteria was performed with 232 Chinese women.

Results

Prothrombin time, international normalized ratio, activated partial thromboplastin time, and activated partial thromboplastin time ratio were shorter, and platelet count decreased gradually during pregnancy, with no change in mean platelet volume; conversely, plasma concentration of both fibrinogen and fibrin/fibrinogen degradation product increased. All these variables were normalized during the postpartum. Reference values by gestational week were established for platelet count, fibrinogen concentration, and fibrin/fibrinogen degradation product concentration.

Conclusions

These reference values may be used in the health assessment of pregnant women with a similar socioeconomic and ethnic background.
Global estimations of the inventory and mitigation potential of methane emissions from rice cultivation conducted using the 2006 Intergovernmental Panel on Climate Change Guidelines
Authors: Yan Xiaoyuan , Akiyama Hiroko , Yagi Kazuyuki , Akimoto Hajime
Published: April 2009

The Intergovernmental Panel on Climate Change (IPCC) regularly publishes guidelines for national greenhouse gas inventories and methane emission (CH4) from rice paddies has been an important component of these guidelines. While there have been many estimates of global CH4 emissions from rice fields, none of them have been obtained using the IPCC guidelines. Therefore, we used the Tier 1 method described in the 2006 IPCC guidelines to estimate the global CH4 emissions from rice fields. To accomplish this, we used country‐specific statistical data regarding rice harvest areas and expert estimates of relevant agricultural activities. The estimated global emission for 2000 was 25.6 Tg a−1, which is at the lower end of earlier estimates and close to the total emission summarized by individual national communications. Monte Carlo simulation revealed a 95% uncertainty range of 14.8–41.7 Tg a−1; however, the estimation uncertainty was found to depend on the reliability of the information available regarding the amount of organic amendments and the area of rice fields that were under continuous flooding. We estimated that if all of the continuously flooded rice fields were drained at least once during the growing season, the CH4 emissions would be reduced by 4.1 Tg a−1. Furthermore, we estimated that applying rice straw off season wherever and whenever possible would result in a further reduction in emissions of 4.1 Tg a−1 globally. Finally, if both of these mitigation options were adopted, the global CH4 emission from rice paddies could be reduced by 7.6 Tg a−1. Although draining continuously flooded rice fields may lead to an increase in nitrous oxide (N2O) emission, the global warming potential resulting from this increase is negligible when compared to the reduction in global warming potential that would result from the CH4 reduction associated with draining the fields.
Investigating Arctic Ocean History: From Speculation to Reality: A Workshop to Prepare for Arctic Ocean Scientific Drilling; Bremerhaven, Germany, 3–5 November 2008
Authors: Coakley Bernard , Stein Ruediger
Published: April 2009

The modern Arctic Ocean appears to be changing faster than any other region. To understand the potential extent of high‐latitude climate change, it is necessary to sample the history stored in the sediments filling the basins and covering the ridges of the Arctic Ocean. These sediments have been imaged with seismic reflection data, but except for the superficial record, which has been piston cored, they have been sampled only in a few locations. In November 2008 a meeting was held at the Alfred Wegener Institute, in Germany, to plan the future of scientific drilling in the Arctic Ocean.
Regions associated with electron physics in asymmetric magnetic field reconnection
Authors: Mozer F. S. , Pritchett P. L.
Published: April 2009

Spatial relationships between regions containing signatures of electron physics in asymmetric reconnection with a guide field are examined using simulations and space observations that are in excellent agreement. These electron physics regions do not completely overlap, are not confined to sizes ∼electron skin depth, and do not surround the X‐line. The electron ideal Ohm's law, E + Ue × B = 0, is violated over many ion inertia lengths in the outflow direction. Thus, pressure terms and, to a lesser extent, inertia terms in the Generalized Ohm's Law are important in producing electron physics on ion scales. Parallel electric fields that are necessary but not sufficient for reconnection are found in the simulation and in space on ion scales in the outflow direction. They account for ∼10% of j · E, averaged over the current sheet. The electron exhaust jet exists over a shorter length for asymmetric reconnection than it does for symmetric reconnection.
Influence of perpendicular magnetic anisotropy on spin-transfer switching current in CoFeB∕MgO∕CoFeB magnetic tunnel junctions
Authors: Yakata S. , Kubota H. , Suzuki Y. , Yakushiji K. , Fukushima A. , Yuasa S. , Ando K.
Published: April 2009

We investigated the spin-torque diode effect in submicron-scale Co60Fe20B20∕MgO∕(CoxFe1−x)80B20 (0⩽x⩽0.9) magnetic tunnel junctions (MTJs) under perpendicular magnetic fields Hext up to 10kOe. A single peak was clearly observed in every spin-torque diode spectrum and the dependence of resonant frequency fres on Hext was well explained by using Kittel’s formula. It was found that effective demagnetizing fields in the perpendicular-to-plane direction of the Fe-rich CoFeB free layers obtained from the spectra were considerably smaller than those expected from the magnetizations of the free layers. This suggested that the Fe-rich CoFeB free layers exhibited a perpendicular magnetic anisotropy, which agreed well with the reduced switching current density in the MTJs.
Spin-polarized transport in the manganite La0.85Ag0.15MnO3
Authors: Gamzatov A. G. , Batdalov A. B. , Melnikov O. V. , Gorbenko O. Yu.
Published: April 2009

The low-temperature minimum of the resistivity of La0.85Ag0.15MnO3 is investigated in detail. Analysis of the experimental data shows that the observed low-temperature minimum of the zero-field resistivity and the large magnetoresistive effect, which increases with decreasing temperature, can be explained in a model of spin-polarized tunneling of charge carriers through grain boundaries.
Substrate temperature effects on laser crystallized NiTi thin films
Authors: Birnbaum A. J. , Chung Ui-Jin , Huang X. , Im James S. , Ramirez A. G. , Yao Y. L.
Published: April 2009

Amorphous sputter-deposited NiTi thin films were subjected to pulsed, melt-mediated laser crystallization techniques to engineer their microstructure. The effects of laser processing of preheated films are examined. Laser processing of films at an elevated substrate temperature has a significant effect on the rate with which solidification occurs. It is observed that the preheating temperature at which processing is carried out has significant implications for the resulting phase and microstructure, and therefore mechanical properties. Furthermore, the microstructural effects of varying incident laser energy density are examined via atomic force microscopy, scanning electron microscopy, and x-ray diffraction, and mechanical/shape memory properties are characterized via nanoindentation.
Maximizing the electron field emission performance of carbon nanotube arrays
Authors: Smith R. C. , Silva S. R. P.
Published: April 2009

The field emission screening effect is one of great importance when aiming to design efficient and powerful cathodes. It has long been assumed that the degrading effect is at a minimum when neighboring emitters are at least twice their height from each other. In this work, we show that the screening effect is underestimated and diminishes at far greater separations of five times the height of the emitter. We further observe that to achieve maximum emission efficiency in an array, one requires a trade off between screening and emitter number, resulting in a separation of three times their height.
Vibrational dynamics of hydrogen on Ge surfaces
Authors: Han Xu , Balgar Thorsten , Hasselbrink Eckart
Published: April 2009

The vibrational dynamics of the H stretch excitation on the Ge(100)−(2×1) and Ge(111)−(1×1) surfaces has been studied using picosecond IR pump–SFG probe spectroscopy. Moreover, the temperature dependence and an isotope mixture effect are reported. The symmetric stretching mode at 1994 cm−1 on the Ge(100)−(2×1):H surface shows a single-exponential relaxation with a decay constant of 4.8±0.6 ns at 100 K with a strong temperature dependence, while the Ge–H stretch at 1975 cm−1 on the Ge(111)−(1×1):H surface relaxes four times faster with a 1.3±0.2 ns lifetime also exhibiting a weaker temperature dependence. The lifetime decreases with increasing temperature to 1.6 and 0.74 ns at 400 K on Ge(100) and Ge(111), respectively. We find that the decay rate increases by a factor of 3–6 depending on sample temperature when the Ge(100) surface dimers are saturated with an isotope mixture of H and D. Such an effect upon isotope mixing is not observed for the Ge(111) surface. The results suggest for the Ge(100)−(2×1):H system that a decay into three bending mode quanta requires the creation of two-optical phonons to satisfy energy conservation, whereas the decay into four bending quanta requires the annihilation of only one phonon. The three bending quanta process is hence the slower one. However, the decay into four bending quanta shows a strong temperature dependence. For an isotope mixture covered surface a larger number of combinations of low-frequency adsorbate modes exist facilitating a faster decay of the stretching excitation.
Room-temperature dislocation climb in metallic interfaces
Authors: Wang Jian , Hoagland Richard G. , Misra Amit
Published: April 2009

Using atomistic simulations, we show that dislocations efficiently climb in metallic interfaces, such as Cu–Nb, through absorption and emission of vacancies and a counter diffusion of Cu atoms in the interfacial plane. The efficiency of dislocation climb is ascribed to the high vacancy concentration of 0.05 in the interfacial plane, the low formation energy of 0.12 eV with respect to removal or insertion of Cu atoms, and the low kinetic barrier of 0.10 eV for vacancy migration. Dislocation climb facilitates reactions of interfacial dislocations and enables interfaces to be in the equilibrium state with respect to concentrations of point defects.
The physical origin of random telegraph noise after dielectric breakdown
Authors: Li X. , Tung C. H. , Pey K. L. , Lo V. L.
Published: April 2009

Our results show that the physical origin of the digital telegraph noise observed in the early stage of the progressive breakdown is originated from the defective oxide with low oxygen concentrations. The outer shells of the percolation path contribute significantly to the random switching of current levels as a result of the ON/OFF state of percolation path. The formation of a nanosize conductive Si path in the inner shell of the percolation path pushes the oxide to a high leakage state and suppresses the visibility of the digital noise.
Membrane orientation of the FMO antenna protein from
Chlorobaculum tepidum
as determined by mass spectrometry-based footprinting
Authors: Wen Jianzhong , Zhang Hao , Gross Michael L. , Blankenship Robert E.
Published: April 2009

The high excitation energy-transfer efficiency demanded in photosynthetic organisms relies on the optimal pigment-protein binding orientation in the individual protein complexes and also on the overall architecture of the photosystem. In green sulfur bacteria, the membrane-attached Fenna-Matthews-Olson (FMO) antenna protein functions as a “wire” to connect the large peripheral chlorosome antenna complex with the reaction center (RC), which is embedded in the cytoplasmic membrane (CM). Energy collected by the chlorosome is funneled through the FMO to the RC. Although there has been considerable effort to understand the relationships between structure and function of the individual isolated complexes, the specific architecture for in vivo interactions of the FMO protein, the CM, and the chlorosome, ensuring highly efficient energy transfer, is still not established experimentally. Here, we describe a mass spectrometry-based method that probes solvent-exposed surfaces of the FMO by labeling solvent-exposed aspartic and glutamic acid residues. The locations and extents of labeling of FMO on the native membrane in comparison with it alone and on a chlorosome-depleted membrane reveal the orientation. The large differences in the modification of certain peptides show that the Bchl
a
#3 side of the FMO trimer interacts with the CM, which is consistent with recent theoretical predictions. Moreover, the results also provide direct experimental evidence to confirm the overall architecture of the photosystem from
Chlorobaculum tepidum
(
C. tepidum
) and give information on the packing of the FMO protein in its native environment.
Polymeric micelles from poly(ethylene glycol)–poly(amino acid) block copolymer for drug and gene delivery
Authors: Osada Kensuke , Christie R. James , Kataoka Kazunori
Published: April 2009

Dramatic advances in biological research have revealed the mechanisms underlying many diseases at the molecular level. However, conventional techniques may be inadequate for direct application of this new knowledge to medical treatments. Nanobiotechnology, which integrates biology with the rapidly growing field of nanotechnology, has great potential to overcome many technical problems and lead to the development of effective therapies. The use of nanobiotechnology in drug delivery systems (DDS) is attractive for advanced treatment of conditions such as cancer and genetic diseases. In this review paper for a special issue on biomaterial research in Japan, we discuss the development of DDS based on polymeric micelles mainly in our group for anti-cancer drug and gene delivery, and also address our challenges associated with developing polymeric micelles as super-functionalized nanodevices with intelligent performance.