bluuebunny/crossref_metadata_2025_split huggingface dataset:
Metal‐Free Synthesis of Imido Derivatives by Direct Oxidation of α‐Amido Sulfones
Authors: Martinelli Fabio , Palmieri Alessandro , Petrini Marino 
Published: July 2010

AbstractOxidation of α‐amidoaryl sulfones with m‐chloroperoxybenzoic acid under mild conditions readily provides the corresponding imides in satisfactory yields. The overall process probably involves formation of an N‐acyliminium ion intermediate, which by attack of the peroxyacid anion generates the final imido derivatives.
Quantification of Sub‐Nanomolar Levels of Aluminum by Adsorptive Stripping Voltammetry Using Rubeanic Acid as a Selective Chelating Agent
Authors: Abbasi Shahryar , Bahiraei Atusa , Farmany Abbas 
Published: July 2010

AbstractA novel, sensitive and selective adsorptive stripping procedure for determination of aluminum is presented. The method is based on the adsorptive accumulation of dithiooxamide (Rubeanic acid) complex of aluminum onto a hanging mercury drop electrode, followed by reduction of adsorbed species by voltammetric scan using differential pulse modulation. The influences of control variables on the sensitivity of the proposed method for the determination of aluminum were studied. The optimum analytical conditions were found to be Rubeanic acid (RA) concentration of 8.0×10−5 M, ammonia buffer (NH3NH4Cl) pH of 6.5, and accumulation potential at −50 mV vs. Ag/AgCl with an accumulation time of 60 s. The peak currents are proportional to the concentration of aluminum over the 0.3–70 ng mL−1 ranges with detection limit of 0.012 ng mL−1. The procedure was applied to the determination of aluminum in the Lab. Water, HCl of Merck and potato samples with satisfactory results.
Analysis of E. coli soluble proteins by non‐denaturing micro 2‐DE/3‐DE and MALDI‐MS‐PMF
Authors: Manabe Takashi , Jin Ya 
Published: July 2010

AbstractEscherichia coli (strain K‐12)‐soluble proteins were analyzed by nondenaturing micro 2‐DE and MALDI‐MS‐PMF. The reported conditions of nondenaturing IEF in agarose column gels [Jin, Y., Manabe, T., Electrophoresis 2009, 30, 939–948] were modified to optimize the resolution of cellular soluble proteins. About 300 CBB‐stained spots, the apparent molecular masses of which ranged from ca. 6000 to 10 kDa, were detected. All the spots on two reference 2‐DE gels (one for wide mass range and one for low‐molecular‐mass range) were numbered and subjected to MALDI‐MS‐PMF for the assignment of constituting polypeptides. Most of the spots (310 spots out of 329) provided significant match (p<0.05) with polypeptides in Swiss‐Prot database and totally 228 polypeptide species were assigned. Activity staining of enzymes such as alkaline phosphatase and catalases was performed on the 2‐DE gels and the locations of the activity spots matched well with those of the MS‐assigned polypeptides of the enzymes. Most of the polypeptides with subunit information in Swiss‐Prot (119 polypeptides as homo‐multimers and 25 as hetero‐multimers out of the 228), such as pyruvate dehydrogenase complex which is composed of three enzymatic components, were detected at the apparent mass positions of their polymers, suggesting that the proteins were separated retaining their subunit structures. When a nondenaturing 2‐DE gel was vertically cut into 2 mm strips and one of the strips was subjected to a third‐dimension micro SDS‐PAGE (micro 3‐DE), about 190 CBB‐stained spots were detected. The assignment of the polypeptides separated on the 3‐DE gel would further provide information on protein/polypeptide interactions.
Protective effect of high protein and calcium intake on the risk of hip fracture in the framingham offspring cohort
Authors: Sahni Shivani , Cupples L Adrienne , Mclean Robert R , Tucker Katherine L , Broe Kerry E , Kiel Douglas P , Hannan Marian T 
Published: July 2010

AbstractThe effect of protein on bone is controversial, and calcium intake may modify protein's effect on bone. We evaluated associations of energy-adjusted tertiles of protein intake (ie, total, animal, plant, animal/plant ratio) with incident hip fracture and whether total calcium intake modified these associations in the Framingham Offspring Study. A total of 1752 men and 1972 women completed a baseline food frequency questionnaire (1991–1995 or 1995–1998) and were followed for hip fracture until 2005. Hazard ratios (HRs) were estimated using Cox proportional hazards regression adjusting for confounders. Baseline mean age was 55 years (SD 9.9 years, range 26 to 86 years). Forty-four hip fractures occurred over 12 years of follow-up. Owing to significant interaction between protein (total, animal, animal/plant ratio) and calcium intake (p interaction range = .03 to .04), stratified results are presented. Among those with calcium intakes less than 800 mg/day, the highest tertile (T3) of animal protein intake had 2.8 times the risk of hip fracture [HR = 2.84, 95% confidence interval (CI) 1.20–6.74, p = .02] versus the lowest tertile (T1, p trend = .02). In the 800 mg/day or more group, T3 of animal protein had an 85% reduced hip fracture risk (HR = 0.15, 95% CI 0.02–0.92, p = .04) versus T1 (p trend = .04). Total protein intake and the animal/plant ratio were not significantly associated with hip fracture (p range = .12 to .65). Our results from middle-aged men and women show that higher animal protein intake coupled with calcium intake of 800 mg/day or more may protect against hip fracture, whereas the effect appears reversed for those with lower calcium intake. Calcium intake modifies the association of protein intake and the risk of hip fracture in this cohort and may explain the lack of concordance seen in previous studies. © 2010 American Society for Bone and Mineral Research.
Relativistic effects in HgHe and HgXe CCSD(T) ground state potential curves. Low‐density viscosity simulations of Hg:Xe mixture
Authors: Bučinský Lukáš , Biskupič Stanislav , Ilčin Michal , Lukeš Vladimír , Laurinc Viliam 
Published: July 2010

AbstractThe comparison of coupled cluster with single and double excitations and with perturbative correction of triple excitations [CCSD(T)] ground state potential curves of mercury with rare gases (RG): HgHe and HgXe, at several levels of theory is presented. The scalar relativistic (REL) effects and spin‐orbit coupling effects in the ground state potential curves of these weakly bounded dimers are considered. The CCSD(T) ground state potential curves at the level of the Dirac‐Coulomb Hamiltonian (DCH) are compared with CCSD(T) curves at the level of 4‐component spin‐free modified DCH, the scalar 2nd order Douglas‐Kroll‐Hess (DKH2) and the nonrelativistic (NR‐LL) (Lévy‐Leblond) Hamiltonian. In addition, London‐Drude formula and SCF interaction energy curves are employed in the analysis of different contributions of REL effects in dissociation energies of HgRG and Hg2 dimers. Moreover, the large anharmonicity of the HgHe ground state potential curve is highlighted. The computationally less demanding scalar DKH2 Hamiltonian is employed to calculate the HgXe, Hg2, and Xe2 all electron CCSD(T) ground state potential curves in highly augmented quadruple zeta basis sets. These potential curves are used to simulate the shear viscosity of mercury, xenon, and mercury‐xenon (Hg:Xe) mixture. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011
A convenient one‐pot procedure for the synthesis of 2‐aryl quinazolines using active MnO2 as oxidant
Authors: Peng Yi‐Yuan , Zeng Yuyun , Qiu Ganyinsheng , Cai Lisheng , Pike Victor W. 
Published: July 2010

Abstract
magnified image A variety of 2‐aryl quinazolines were synthesized from the condensation of 2‐aminobenzylamines and aryl aldehydes to form 2‐aryl‐1,2,3,4‐tetrahydroquinazolines and subsequent oxidation of the intermediates with MnO2. J. Heterocyclic Chem., (2010).
Soil amendment with agro‐industrial byproducts: molecular‐chemical compositions and effects on soil biochemical activities and phosphorus fractions
Authors: Negassa Wakene , Baum Christel , Leinweber Peter 
Published: July 2010

AbstractEnvironmental pollution by agro‐industrial byproducts in developing countries can be alleviated by recycling into soils. However, little is known about their chemical composition and impact on soil fertility. Therefore, the objectives of the present study were (1) to characterize the molecular‐chemical composition of dry (COD) and wet (COW) coffee, sisal (SIS), barley malt of brewery (BEB), and sugarcane processing (FIC) byproducts, and filter cakes of linseed (LIC) and niger seed (NIC) and (2) to evaluate their effects on respiration, pH, enzyme activities, and P fractions of a tropical soil. The agro‐industrial byproducts significantly differed in their concentrations of plant nutrients and organic‐matter compositions. The highest proportions of lipids, phenols + lignin monomers, and alkylaromatics were observed in COD, N‐containing compounds in COW, sterols in FIC, peptides in LIC, suberin in SIS, and fatty acid in COW and FIC. The application of the byproducts at the rate of 40 kg P ha–1 (1.1 to 13.2 g C [kg soil]–1) significantly (p < 0.05) increased the rate and cumulative soil respiration, soil pH, acid phosphatase and urease activities, and labile inorganic P over the control treatment. Ranking the qualities of the agro‐industrial byproducts for soil amendment based on their composition and effects on soil properties revealed the order NIC > LIC > BEB > COW > SIS > FIC > COD.
Carotenoid content impacts flavor acceptability in tomato (Solanum lycopersicum)
Authors: Vogel Jonathan T , Tieman Denise M , Sims Charles A , Odabasi Asli Z , Clark David G , Klee Harry J 
Published: July 2010

AbstractBACKGROUND: Tomatoes contain high levels of several carotenoids including lycopene and β‐carotene. Beyond their functions as colorants and nutrients, carotenoids are precursors for important volatile flavor compounds. In order to assess the importance of apocarotenoid volatiles in flavor perception and acceptability, we conducted sensory evaluations of near‐isogenic carotenoid biosynthetic mutants and their parent, Ailsa Craig.RESULTS: The carotenoid contents of these tomatoes were extremely low in the r mutant, increased in lycopene in old gold, and higher in tetra‐cis‐lycopene and ζ‐carotene in tangerine. The volatiles derived from these carotenoids (β‐ionone, geranylacetone and 6‐methyl‐5‐hepten‐2‐one) were proportionally altered relative to their precursors. Fruits were also analyzed for soluble solids, sugars, acids and flavor volatiles. Consumer panels rated the r mutant lowest for all sensory attributes, while Ailsa Craig was generally rated highest. Old gold and tangerine were rated intermediate in two of the three harvests.CONCLUSIONS: Several chemicals were negatively correlated with at least one of the hedonic scores while several others were positively correlated with tomato flavor acceptability. The results permitted identification of positive and negative interactions of volatiles with tomato flavor. Copyright © 2010 Society of Chemical Industry
The influence of monoacylglycerol and L‐glutamic acid on the viscoelastic properties of wheat flour dough and sensory characteristics of French loaf product
Authors: Pečivová Pavlína , Burešová Iva , Bílková Hana 
Published: July 2010

AbstractBACKGROUND: The influence of monoacylglycerol Rimulsoft Super(V) and L‐glutamic acid added to wheat flour dough was studied. Properties of the doughs were evaluated on the basis of chemical analysis and rheological measurements on a farinograph. Bakery products made from these doughs were subsequently subjected to sensory analyses.RESULTS: It was found that L‐glutamic acid influenced the water absorption in dough more (50.0 g kg−1; water absorption 56.6%) than monoacylglycerol Rimulsoft Super(V) (50.0 g kg−1; water absorption 55.0%). Farinograph measurements showed that doughs with the addition of L‐glutamic acid resembled flour containing high‐quality gluten, but dough with the addition of monoacylglycerol Rimulsoft Super(V) corresponded to ‘weak’ flour.Sensory analyses revealed that, in comparison with the control sample of French loaf, the saliva‐absorbing capacity increased in the French loaf with the highest addition of L‐glutamic acid (30.0 g kg−1). Deterioration in quality and texture in French loaf with addition of L‐glutamic acid (8.0 g kg−1, 30.0 g kg−1) was noted. No other statistically significant differences were found.CONCLUSION: It is acceptable to add both additives to dough in order to modify its rheological properties. Copyright © 2010 Society of Chemical Industry
The influence of organic/integrated production on the content of phenolic compounds in apple leaves and fruits in four different varieties over a 2‐year period
Authors: Petkovsek Maja Mikulic , Slatnar Ana , Stampar Franci , Veberic Robert 
Published: July 2010

AbstractBACKGROUND: Phenolics in fruit may be influenced by the fruit type, cultivation conditions of a plant, climatic conditions, growing season, storage conditions, and industrial processing. The aim of this study was to compare single phenolic compounds, total phenolics and antioxidant capacity of four varieties of apple grown under organic and integrated conditions over a 2‐year period.RESULTS: Several different phenolic compounds belonging to the groups of hydroxycinnamic acids, flavanols, dihydrochalcones, flavonols and anthocyanins were quantified. The levels of all analysed groups of phenolics were higher (not always significantly) in the organically grown apple leaves and fruit than in the leaves or apples from integrated production. Leaves from organic trees had 10–20% higher content levels of total phenols than the leaves from trees in the integrated growing system. In both years, organic production affected the increase in the antioxidant activity of apple peel. Organic apples have higher total phenolic content than the integrated grown ones.CONCLUSION: Cultivation type had an important influence on the polyphenolic level and antioxidant capacity of the apple fruits and leaves. Apples from organic production showed a higher content of hydroxycinnamic acids, flavanols, dihydrochalcones, quercetins and total phenolics than apples from integrated cultivation. Copyright © 2010 Society of Chemical Industry
Changes in phenolic compounds and Rancimat stability of olive oils from varieties of olives at different stages of ripeness
Authors: Nieto Leopoldo Martínez , Hodaifa Gassan , Lozano Peña Juan Luis 
Published: July 2010

AbstractBACKGROUND: Recently, diets rich in natural foods and food‐derived components, such as phenolic compounds, have received a great deal of attention because they are perceived as ‘safe’ and ‘non‐medicinal’. In fact, some are known to function as chemopreventive agents against oxidative damage, cerebrovascular disease, and aging.RESULTS: Phenolic compounds, natural antioxidants present in virgin olive oil, play an important role in oil quality by contributing significantly to protecting oil stability against oxidation. In addition, polyphenols are the main contributors to olive oil bitterness, astringency and pungency. The data were fit by linear regression, giving Rancimat stability (h) = 0.18× Total polyphenols (mg L−1) in the virgin olive oil.CONCLUSIONS: The practice of harvesting ripe olives as soon as possible to produce oils of high phenolic contents and thus high oxidative stability implies bitter and piquant oils, this being admissible for oils of some varieties but detrimental to others appreciated in the market for being more fruity and sweeter. Copyright © 2010 Society of Chemical Industry
ADMET‐Polymerization of Dienes based on Sustainable Chemicals
Authors: Günther Stefan , Lamprecht Patrick , Luinstra Gerrit A. 
Published: July 2010

AbstractSummary: Eugenol and isoeugenol were used as natural based starting materials to prepare unsaturated polyethers and polycarbonates. The polymerization was achieved in a two step procedure exploiting the orthogonal phenol and ene functionalities. Thus diene terminated ethers and organic carbonates were obtained from eugenol and isoeugenol, and subjected to ADMET polymerisation using Grubbs 2nd generation catalyst1. The obtained unsaturated polymers have molecular weights ranging from 2.700 to 32.000 g/mol. Molecular weight build up was partly restricted by the low solubility of the products.
Ring Closing Metathesis Using Chiral Template Consisting of Hard and Soft Parts
Authors: Siddiki Hakim S. M. A. , Sugimura Takashi 
Published: July 2010

AbstractSummary: Macrocyclic compounds having 18‐, 19‐, 22‐, and 23‐membered rings were prepared quantitatively by ring closing metathesis of diene substrates consisting of a rigid o‐ or m‐phthalate group and flexible but geometrically regulated 2,4‐pentanediol tethers. From the p‐phthalate analogues, the ring closing metathesis and the cyclic dimmer formation were observed to give 24‐membered ring (70% yield) and 40‐membered ring (65% yield) respectively.
Mesoporous Molecular Sieves as Advanced Supports for Olefin Metathesis Catalysts
Authors: Balcar Hynek , Čejka Jiří 
Published: July 2010

AbstractSummary: Siliceous mesoporous molecular sieves MCM‐41, MCM‐48 and SBA‐15 and organised mesoporous alumina represent progressive supports for new heterogeneous catalysts for olefin metathesis and metathesis polymerization. In combination with Mo and Re oxides they provide catalysts of considerably higher activity in comparison with those based on conventional silica and alumina. Immobilization of Mo and Ru alkylidenes on these materials led to the highly active and selective catalysts with negligible leaching of transition metal.
Imidazol(in)ium‐2‐Carboxylates as N‐Heterocyclic Carbene Ligand Precursors for Ruthenium Metathesis Initiators
Authors: Sauvage Xavier , Demonceau Albert , Delaude Lionel 
Published: July 2010

AbstractSummary: Imidazol(in)ium‐2‐carboxylates were used as N‐heterocyclic carbene (NHC) ligand precursors to convert the [RuCl2(p‐cymene)]2 dimer into three ruthenium‐arene complexes of the [RuCl2(p‐cymene)(NHC)] type. The decarboxylation of NHC · CO2 betaines also provided a convenient synthetic path to prepare five well‐known ruthenium‐NHC catalysts for olefin metathesis and related reactions, including the second generation Grubbs and Hoveyda–Grubbs catalysts, via ligand exchange with phosphine‐containing, first generation ruthenium‐benzylidene or indenylidene complexes. Both procedures are particularly attractive from a practical point of view, because NHC · CO2 adducts are stable zwitterionic compounds that can be stored and handled with no particular precautions.
Ring‐Opening Metathesis Polymerization of Cyclooctyne Employing Well‐Defined Tungsten Alkylidyne Complexes
Authors: Lysenko Sergej , Haberlag Birte , Wu Xian , Tamm Matthias 
Published: July 2010

AbstractSummary: The ring‐opening metathesis polymerization of cyclooctyne was studied was studied in the presence of catalytic amounts of the tungsten alkylidyne complexes [RCW(NImtBu){OCMe(CF3)2}2] (1a: R = CMe3, 1b: R = Ph). The resulting polymers show relatively narrow polydispersities with the PDI ranging from 1.2 to 2.4. Treatment of 1b with cyclooctyne in dilute toluene or hexane solution afforded only low molecular weight oligomers. The mass spectra of these oligomers indicate the existence of macrocycles of the formula [C(CH2)6C]n (n = 3–9). In contrast, reactions at high substrate concentration led to mixtures of cyclic oligomers and linear polymers, which is probably a result of ring‐chain equilibria, established in agreement with the Jacobson‐Stockmayer theory of macrocyclization. In contrast, treatment of neat cyclooctyne with a catalytic amount of the catalyst produced medium molecular weight polymers in good yields.
Decomposition of mixtures' spectra by multivariate curve resolution of rapidly acquired TOCSY experiments
Authors: Castellanos Eddy Rocío Rey , Wist Julien 
Published: July 2010

AbstractA method is presented that allows for retrieving 1D spectra of the individual components of a mixture from a sparsely acquired 2D‐TOCSY spectrum. The decomposition of the 2D‐TOCSY data into pure 1D traces is achieved using a non‐negative matrix factorization algorithm, also known as multivariate curve resolution analysis. Here, we show that the algorithm can be applied to data processed in the direct dimension only. Thus, our method can be applied to non‐linearly sampled experiments or data acquired with few indirect points. An example is shown for the spectra of a mixture of six amino acids, acquired in 15 min. Copyright © 2010 John Wiley & Sons, Ltd.
Fast multidimensional localized parallel NMR spectroscopy for the analysis of samples
Authors: Vega‐Vazquez Marino , Cobas Juan Carlos , Martin‐Pastor Manuel 
Published: July 2010

AbstractA parallel localized spectroscopy (PALSY) method is presented to speed up the acquisition of multidimensional NMR (nD) spectra. The sample is virtually divided into a discrete number of nonoverlapping slices that relax independently during consecutive scans of the experiment, affording a substantial reduction in the interscan relaxation delay and the total experiment time. PALSY was tested for the acquisition of three experiments 2D COSY, 2D DQF‐COSY and 2D TQF‐COSY in parallel, affording a time‐saving factor of 3–4. Some unique advantages are that the achievable resolution in any dimension is not compromised in any way: it uses conventional NMR data processing, it is not prone to generate spectral artifacts, and once calibrated, it can be used routinely with these and other combinations of NMR spectra. Copyright © 2010 John Wiley & Sons, Ltd.
Wenn Wissensträger in den Ruhestand gehen
Authors: Riese Christian 
Published: July 2010

AbstractDer demografische Wandel macht vor der chemischen Industrie nicht halt: In den nächsten Jahren werden die über 50‐jährigen die größte Gruppe in vielen Unternehmen sein, und wenn sie in Ruhestand gehen, geht Know‐how verloren.
Systematic evaluation of the miRNA‐ome and its downstream effects on mRNA expression identifies gastric cancer progression
Authors: Tchernitsa Oleg , Kasajima Atsuko , Schäfer Reinhold , Kuban Ralf‐Jürgen , Ungethüm Ute , Györffy Balazs , Neumann Ulf , Simon Eva , Weichert Wilko , Ebert Matthias PA , Röcken Christoph 
Published: July 2010

AbstractWe investigated the differential expression of Dicer and Drosha, as well as that of microRNA (miRNA), in adjacent normal and tumour samples of patients with gastric cancer. The expression of Dicer and Drosha was studied by immunohistochemistry in 332 gastric cancers and correlated with clinico‐pathological patient characteristics. Differential expression of miRNAs was studied using the Invitrogen NCode™ Multi‐Species miRNA Microarray Probe Set containing 857 mammalian probes in a test set of six primary gastric cancers (three with and three without lymph node metastases). Differential expression was validated by RT‐PCR on an independent validation set of 20 patients with gastric cancer. Dicer and Drosha were differentially expressed in non‐neoplastic and neoplastic gastric tissue. The expression of Drosha correlated with local tumour growth and was a significant independent prognosticator of patient survival. Twenty miRNAs were up‐ and two down‐regulated in gastric carcinoma compared with non‐neoplastic tissue. Six of these miRNAs separated node‐positive from node‐negative gastric cancers, ie miR‐103, miR‐21, miR‐145, miR‐106b, miR‐146a, and miR‐148a. Five miRNAs expressed differentially in node‐positive cancers had conserved binding sites for mRNAs differentially expressed in the same set of tumour samples. Gastric cancer shows a complex derangement of the miRNA‐ome, including Dicer and Drosha. These changes correlate independently with patient prognosis and probably influence local tumour growth and nodal spread. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.