bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of (−)‐Pinellic Acid and Its (9R,12S,13S)‐Diastereoisomer
Authors: Sabitha Gowravaram , Bhikshapathi Martha , Reddy Erigala Venkata , Yadav Jhillu S. 
Published: October 2009

AbstractThe total synthesis of (−)‐pinellic acid with (9S,12S,13S)‐configuration and its (9R,12S,13S)‐diastereoisomer was achieved in high overall yields from a common intermediate derived from (+)‐L‐diethyl tartrate.
Synthesis and Crystal Structures of O‐2′,3′‐Cyclic Cyclopentanone and Cyclohexanone Ketals of the Cytostatic 5‐Fluorouridine
Authors: Malecki Edith , Ye Fei , Reuter Hans , Rosemeyer Helmut 
Published: October 2009

AbstractThe synthesis of two O‐2′,3′‐cyclic ketals, i.e., 5 and 6, of the cytostatic 5‐fluorouridine (2), carrying a cyclopentane and/or a cyclohexane ring, respectively, is described. The novel compounds were characterized by 1H‐, 19F‐, and 13C‐NMR, and UV spectroscopy, as well as by elemental analyses. Their crystal structures were determined by X‐ray analysis. Both compounds 5 and 6 show an anti‐conformation at the N‐glycosidic bond which is biased from +ac to +ap compared to the parent nucleoside 2. The sugar puckering is changed from 2′E to 3′E going along with a reduction of the puckering amplitude τm by ca. 10–13° due to the ketalization. The conformation about the sugar exocyclic bond C(4′)C(5′) of 5 and 6 remains unchanged, i.e., g+, compared with compound 2.
Two New Diterpenes from the Twigs of Cinnamomum cassia
Authors: Ngoc Tran Minh , Ha Do Thi , Lee Ik‐Soo , Min Byung‐Sun , Na Min‐Kyun , Jung Hyun‐Ju , Lee Sang‐Myung , Bae Ki‐Hwan 
Published: October 2009

AbstractTwo new diterpene derivatives named cinnacasol (1) and cinnacaside (2) were isolated from the MeOH extract of the twigs of Cinnamomum cassia Blume. Their structures were identified based on physicochemical properties and spectroscopic‐data analyses such as IR, HR‐MS, and 1D‐ and 2D‐NMR, and by comparison with published values.
Synthesis and Crystal Structures of Two 9‐(2‐Bromoethyl)‐Substituted 7‐Deazapurines
Authors: Asaftei Simona , Reichelt Martin , Reuter Hans , Rosemeyer Helmut 
Published: October 2009

AbstractThe 7‐(2‐bromoethyl) derivatives, 2a and 2b, of 4‐chloro‐7H‐pyrrolo[2,3‐d]pyrimidine (1a) and 4‐chloro‐7H‐pyrrolo[2,3‐d]pyrimidin‐2‐amine (1b) were synthesized by nucleobase anion alkylation (NaH, DMF) and crystallized. X‐Ray analyses of both compounds were performed, and they revealed significantly different positioning of the side chain relative to the heterocyclic ring, depending on the substituent (H or NH2) at C(2).
Three New Monoterpene Glucosides from Lamium amplexicaule
Authors: Kikuchi Masao , Onoguchi Rie , Yaoita Yasunori 
Published: October 2009

AbstractThree new monoterpene glucosides, lamiuamplexosides A–C (1–3), along with thirteen known glucosides, were isolated from the whole plant of Lamium amplexicaule L. The structures of 1–3 were elucidated on the basis of spectroscopic, chemical, and physicochemical evidence.
2‐(2,4‐Dinitrobenzyl)pyridine (DNBP): A Potential Light‐Activated Proton Shuttle
Authors: Goeschen Catrin , Herges Rainer , Richter Josef , Tokarczyk Bogdan , Wirz Jakob 
Published: October 2009

AbstractThe well‐known photochromic tautomerism of 2‐(2,4‐dinitrobenzyl)pyridine (1; CH; Scheme 1) was re‐investigated by flash photolysis in aqueous solution in view of its potential application as a light‐activated proton pump. Irradiation of 1 yields the enamine tautomer NH (λmax=520 nm) that rapidly equilibrates with its conjugate base CNO− (λmax=420 nm). The pH–rate profile for the first‐order decay of NH and CNO− provides a direct determination of the acidity constant of NH, pK$\rm{ {_{a,c}^{NH}}}$=5.94±0.12 (I=0.1M) and serves to clarify the mechanisms of proton transfer prevailing in aqueous solutions. The acidity constant of protonated 1 (CHNH+), pK$\rm{ {_{a,c}^{CHNH}}}$=4.18±0.02, was determined by spectrophotometric titration.
Chemical and Genetic Study of Ligularia cyathiceps in Yunnan Province of China
Authors: Nagano Hajime , Torihata Atsushi , Matsushima Mika , Hanai Ryo , Saito Yoshinori , Baba Makiko , Tanio Yui , Okamoto Yasuko , Takashima Yuriko , Ichihara Mayu , Gong Xun , Kuroda Chiaki , Tori Motoo 
Published: October 2009

AbstractRoot chemicals and evolutionarily neutral DNA regions in L. cyathiceps samples collected in the Zhongdian (Shangrila) County of Yunnan, P. R. China, were examined. Twenty compounds were isolated, including three new ones, 1β,10β‐epoxy‐6β‐(propionyloxy)furanoeremophilan‐9‐one (6), 1β,10β‐epoxy‐8α‐ethoxyeremophila‐6,11‐diene (14), and 11αH‐6β‐isobutyryloxy‐1β,10β,7β,8β‐diepoxyeremophilan‐12,8α‐olide (15). The chemical diversity was found to be limited, with cacalol (1) and 6‐(acyloxy)furanoeremophilan‐9‐ones (4 and/or 5) being major components in all the samples. The nuclear ribosomal RNA gene was also found to harbor little variation, although two distinct sequence types were found for the plastid atpB‐rbcL intergenic region.
The sensitivity of simulated flow and water quality response to spatial heterogeneity on a hillslope in the Tarrawarra catchment, Australia
Authors: Neumann L. N. , Western A. W. , Argent R. M. 
Published: October 2009

AbstractModels are widely used to simulate hydrological response and the generation and transport of constituents such as salt, phosphorus, and nitrogen from catchments to streams. Several models use a spatial representation with catchments divided into subcatchments. Variations in land use and other characteristics within subcatchments are represented by spatially lumped hydrologic response units (HRUs) or functional units instead of using fully distributed models. This approach disregards any spatial interaction between HRUs, including their connectivity to each other and to the stream and the influence of these interactions on water and constituent export. A spatially explicit hydrological model (Thales) was used to simulate a variety of theoretical catchments with soils dominated by combinations of infiltration excess, saturation excess, and subsurface stormflow processes and different soil constituent concentrations that were spatially interacting (i.e. located along a hillslope sequence). The modelling results show that the response of both runoff and concentration is sensitive to varying spatial arrangements due to interactions of runoff, infiltration, and chemical processes between the different soil types in many but not all situations. Results highlight the importance of considering connectivity of pathways when modelling hydrological response and constituents export. This is achieved by comparing pairs of simulations and the corresponding differences in the exported loads. Copyright © 2009 John Wiley & Sons, Ltd.
Multi‐armed poly(L‐glutamic acid)‐graft‐oligoethylenimine copolymers as efficient nonviral gene delivery vectors
Authors: Chen Lei , Tian Huayu , Chen Jie , Chen Xuesi , Huang Yubin , Jing Xiabin 
Published: October 2009

AbstractBackgroundThe application of polyethylenimine (PEI) in gene delivery has been severely limited by significant cytotoxicity that results from a nondegradable methylene backbone and high cationic charge density. It is therefore necessary to develop novel biodegradable PEI derivates for low‐toxic, highly efficient gene delivery.MethodsA series of novel cationic copolymers with various charge density were designed and synthesized by grafting different kinds of oligoethylenimine (OEI) onto a determinate multi‐armed poly(L‐glutamic acid) backbone. The molecular structures of multi‐armed poly(L‐glutamic acid)‐graft‐OEI (MP‐g‐OEI) copolymers were characterized using nuclear magnetic resonance, viscosimetry and gel permeation chromatography. Moreover, the MP‐g‐OEI/DNA complexes were measured by a gel retardation assay, dynamic light scattering and atomic force microscopy to determine DNA binding ability, particle size, zeta potential, complex formation and shape, respectively. MP‐g‐OEI copolymers were also evaluated in Chinese hamster ovary and human embryonic kidney‐293 cells for their cytotoxicity and transfection efficiency.ResultsThe particle sizes of MP‐g‐OEI/DNA complexes were in a range of 109.6–182.6 nm and the zeta potentials were in a range of 29.2–44.5 mV above the N/P ratio of 5. All the MP‐g‐OEI copolymers exhibited lower cytotoxicity and higher gene transfection efficiency than PEI25k in the absence and presence of serum with different cell lines. Importantly, the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay revealed that the cytotoxicity of MP‐g‐OEI copolymers varied with their molecular weight and charge density, and two of MP‐g‐OEI copolymers (OEI600‐MP and OEI1800‐MP) could achieve optimal transfection efficiency at a similar low N/P ratio as that for PEI25k.ConclusionsMP‐g‐OEI copolymers demonstrated considerable potential as nonviral vectors for gene therapy. Copyright © 2009 John Wiley & Sons, Ltd.
Evaluation of Raman and SERS analytical protocols in the analysis of Cape Jasmine dye (Gardenia augustaL.)
Authors: Cañamares M. V. , Leona M. , Bouchard M. , Grzywacz C. M. , Wouters J. , Trentelman K. 
Published: October 2009

AbstractThe identification of organic colorants in works of art (such as dyes on textiles or organic pigments) by Raman spectroscopy is generally limited by the presence of a strong fluorescence background. In this paper, the effectiveness of minimizing fluorescence in the analysis of Cape Jasmine (Gardenia augustaL.) by dispersive Raman spectroscopy at three different excitation wavelengths (633, 785 and 1064 nm) and by surface‐enhanced Raman spectroscopy (SERS) with and without acid hydrolysis is evaluated and compared. It is shown that these vibrational techniques offer an alternative analytical approach, when, as is particularly the case of Cape Jasmine, sample preparation procedures that are routinely applied for natural organic dyes and pigments cause alterations that lead to low sensitivity in the more classical high‐performance liquid chromatography‐photodiode array (HPLC‐PDA) analytical protocols. Samples of the yellow dyeG. augustaL. in the following forms were analyzed: dyed on alum mordanted wool, dyed on nonmordanted and alum mordanted silk, pigment precipitated on hydrated aluminum oxide, extract mixed with a protein binder and painted on glass, and as a water‐based glaze applied on a mock‐up of a typical Chinese wall‐painting. Raman bands at 1537, 1209 and 1165 cm−1are identified as discriminating markers for the carotenoid colorant components crocetin and crocin. Copyright © 2009 John Wiley & Sons, Ltd.
Improved surface‐enhanced Raman scattering properties of TiO2 nanoparticles by Zn dopant
Authors: Yang Libin , Zhang Yu , Ruan Weidong , Zhao Bing , Xu Weiqing , Lombardi John R. 
Published: October 2009

AbstractIn this paper, pure and Zn‐doped TiO2 nanoparticles (NPs) with various content of Zn were prepared by a sol–hydrothermal method and were employed as active substrates for surface‐enhanced Raman scattering (SERS). On the 3% Zn‐doped TiO2 substrate, 4‐mercaptobenzoic acid(4‐MBA) molecules exhibit a higher SERS intensity by a factor of 6, as compared with the native enhancement of 4‐MBA adsorbed on undoped TiO2 NPs. Moreover, the higher SERS activity was still observed on the 3% Zn‐doped TiO2 NPs at temperature even up to 125 °C. These results indicate that an appropriate amount of Zn doping can improve the SERS performances of TiO2 SERS‐active substrates. The introduction of Zn dopant can enrich the surface states (defects) of TiO2 and improve the separation efficiency of photo‐generated charge carriers (electrons and holes) in TiO2, according to measurements of X‐ray diffraction, UV‐visible diffuse reflectance spectroscopy, and photoluminescence, which are responsible for the influence of Zn dopant on the improved SERS performances of TiO2 NPs. Copyright © 2009 John Wiley & Sons, Ltd.
Extensive lymphadenectomy in colorectal cancer with isolated para‐aortic lymph node metastasis below the level of renal vessels
Authors: Choi Pyong Wha , Kim Hee Cheol , Kim Ah Young , Jung Sang Hun , Yu Chang Sik , Kim Jin Cheon 
Published: October 2009

AbstractBackground and objectivesThe effects of isolated metastatic node dissection in the para‐aortic region have not been established in colorectal cancer (CRC). The authors undertook to evaluate the role of para‐aortic lymph node (PALN) dissection in CRC with isolated PALN metastasis.MethodsBetween January 1993 and March 2006, 24 patients underwent PALN dissection for isolated PALN metastasis from CRC. Patients with distant metastases other than to PALNs, or with nodal metastasis above the celiac axis were excluded. The control group was composed of 53 patients with isolated PALN metastasis below the level of the renal hilum that was not surgically removed.ResultsMedian disease‐free interval after PALN dissection was 14 months. The postoperative complication rate was 27.8%, which was not significantly different from that of the control group. Median survivals in the PALN dissection and control groups were 64 (range, 17–111) and 33 (range, 24–42) months, respectively. The overall 5‐year survival rate was 53.4% in the PALN dissection group, versus 12.0% in the control group (P = 0.045).ConclusionsThe findings of this study suggest that PALN dissection increases the survival of patients with isolated PALN metastasis from CRC, and that it has a tolerable morbidity rate. J. Surg. Oncol. 2010;101:66–71. © 2009 Wiley‐Liss, Inc.
Characterization and quantitation of short‐chain fructooligosaccharides and inulooligosaccharides in fermented milks by high‐performance anion‐exchange chromatography with pulsed amperometric detection
Authors: Borromei Chiara , Cavazza Antonella , Merusi Cristiana , Corradini Claudio 
Published: October 2009

AbstractWith the increased interest in the possible link between fructooligosaccharides (FOS) intake from functional foods and health, the need for reliable data on the individual FOS content of those foods has become very important. In this study a new high‐performance anion‐exchange chromatography coupled to pulsed amperometric detection (HPAEC‐PAD) method is described for the selective determination of short‐chain FOS and inulooligosaccharides (IOS) present in the investigated prebiotic food ingredients. Response factor of PAD was investigated in relationship with degree of polymerization and isomers. The developed HPAEC‐PAD method has been applied to characterize short‐chain oligosaccharides of the inulin series with DP ranging from DP3 to DP7 and IOS from DP2 to DP7. Their quantification in commercial water‐soluble fibers of relevant importance as prebiotic food ingredient added in fermented milks has been performed. In order to evaluate the reliability of the proposed method, results have been compared with those obtained by the official enzymatic method. Furthermore, this new HPAEC‐PAD method may contribute to clarify the real importance, prebiotic effectiveness and biological role of these carbohydrates.
Quantitative determination of 16 polycyclic aromatic hydrocarbons in soil samples using solid‐phase microextraction
Authors: Wang Yonghua , Zhang Juan , Ding Youchao , Zhou Jia , Ni Lixiao , Sun Cheng 
Published: October 2009

AbstractA method for the determination of polycyclic aromatic hydrocarbons (PAHs) in soil samples using ultrasonic‐assisted extraction with internal surrogates combined with solid‐phase microextraction and GC‐MS has been developed. Five kinds of commercial solid‐phase microextraction fibers, 100 μm PDMS, 30 μm PDMS, 65 μm PDMS/DVB, 50 μm DVB/CAR/PDMS and 85 μm PA, were compared to choose the optimal SPME fiber for extraction of PAHs. One hundred micrometers of PDMS fiber was found to be more suitable for the determination of PAHs due to its wider linear range, better repeatability, lower detection and more satisfactory efficacy than the other fibers. Under the recommended conditions, 100 μm PDMS fiber could provide low nanogram level detection limits with correlation coefficient greater than 0.98. The method was also applied to determine PAHs in a spiked soil sample, obtaining recoveries higher than 79.3%. A field study with naturally contaminated samples from local contaminated sites was carried out. The proposed method was found to be a reliable, inexpensive and simple preparation method for quantitative determination of 16 PAHs in soil samples.
CE‐ECL detection of gatifloxacin in biological fluid after clean‐up using SPE
Authors: Fu Zhifeng , Wang Lin , Li Cuifang , Liu Ying , Zhou Xueting , Wei Wei 
Published: October 2009

AbstractA simple, rapid and sensitive CE method has been proposed for the determination of gatifloxacin in biological fluid. This method is based on the ECL reaction of gatifloxacin and tris(2,2'‐bipyridyl)ruthenium(II) occurred in the end‐column detection cell. Under the optimal conditions, gatifloxacin can be assayed within 10 min over the concentration range of 5.0×10−8−5.0×10−6 g/mL with the theoretical plate numbers of 18 000. The intra‐day and inter‐day precision of the signal intensity and the migration time shows acceptable reproducibility for the analysis of gatifloxacin. The presented method has been successfully applied to determine the concentrations of gatifloxacin in urine and blood samples after clean‐up using C18 SPE column.
The impact of killing in war on mental health symptoms and related functioning
Authors: Maguen Shira , Metzler Thomas J. , Litz Brett T. , Seal Karen H. , Knight Sara J. , Marmar Charles R. 
Published: October 2009

AbstractThis study examined the mental health and functional consequences associated with killing combatants and noncombatants. Using the National Vietnam Veterans Readjustment Study (NVVRS) survey data, the authors reported the percentage of male Vietnam theater veterans (N = 1200) who killed an enemy combatant, civilian, and/or prisoner of war. They next examined the relationship between killing in war and a number of mental health and functional outcomes using the clinical interview subsample of the NVVRS (n = 259). Controlling for demographic variables and exposure to general combat experiences, the authors found that killing was associated with posttraumatic stress disorder symptoms, dissociation, functional impairment, and violent behaviors. Experiences of killing in war are important to address in the evaluation and treatment of veterans.
Studies on Preparation and Fluorescent Properties of a Novel Photo‐Sensitive Nanoparticle Composed of Europium Ion and Cinnamic Acid Derivative
Authors: Shi Dongjian , Liu Xiaoya , Xiang Fei , Chen Mingqing , Yang Cheng , Akashi Mitsuru 
Published: October 2009

AbstractA novel fluorescent and photo‐sensitive nanoparticle was self‐assembled from an europium‐based random copolymer, europium coordinated poly(methylacrylic acid)‐co‐poly(cinnamyl acrylate) (PMCFA‐Eu3+), which was synthesized from methylacrylic acid (MAA), and Eu3+‐cinnamyl acrylate derivative (CFA) by radical polymerization. DLS and TEM results indicated the formation of spherical nanoparticles with 120 nm in diameter. The PMCFA‐Eu3+ complex showed stronger fluorescence than Eu3+, indicating the effective energy transferred from the ligand to Eu3+. Moreover, the photo‐crosslinking of the cinnamate groups induced a decrease in the diameter and an increase in the fluorescent properties of the PMCFA‐Eu3+ nanoparticles. This functional nanoparticle might be useful as a carrier and a fluorescence probe in biomedical and fluorescent fields.magnified image
The balanced billing cycle vehicle routing problem
Authors: Groër Chris , Golden Bruce , Wasil Edward 
Published: October 2009

AbstractUtility companies typically send their meter readers out each day of the billing cycle in order to determine each customer's usage for the period. Customer churn requires the utility company to periodically remove some customer locations from its meter‐reading routes. On the other hand, the addition of new customers and locations requires the utility company to add new stops to the existing routes. A utility that does not adjust its meter‐reading routes over time can find itself with inefficient routes and, subsequently, higher meter‐reading costs. Furthermore, the utility can end up with certain billing days that require substantially larger meter‐reading resources than others. However, remedying this problem is not as simple as it may initially seem. Certain regulatory and customer service considerations can prevent the utility from shifting a customer's billing day by more than a few days in either direction. Thus, the problem of reducing the meter‐reading costs and balancing the workload can become quite difficult. We describe this Balanced Billing Cycle Vehicle Routing Problem in more detail and develop an algorithm for providing solutions to a slightly simplified version of the problem. Our algorithm uses a combination of heuristics and integer programming via a three‐stage algorithm. We discuss the performance of our procedure on a real‐world data set. © 2009 Wiley Periodicals, Inc. NETWORKS, 2009
Fixed routes with backup vehicles for stochastic vehicle routing problems with time constraints
Authors: Erera Alan L. , Savelsbergh Martin , Uyar Emrah 
Published: October 2009

AbstractWe propose a practical and flexible fixed routing system that preserves many of the benefits of traditional fixed routes but can be deployed in settings with medium to high variability and delivery time window constraints. The key ideas are the introduction of a new recourse strategy, in which customers are assigned to two planned routes, a primary and a backup, and recourse decisions can move customers to backup routes to regain feasibility or improve costs, and the use of sampling‐based techniques to handle the presence of delivery time windows during the construction of primary and backup routes. A computational study based on real‐life data demonstrates the efficacy of the proposed fixed routing system and the route construction techniques. © 2009 Wiley Periodicals, Inc. NETWORKS, 2009
Complexity of some inverse shortest path lengths problems
Authors: Cui Tingting , Hochbaum Dorit S. 
Published: October 2009

AbstractThe input to an inverse shortest path lengths problem (ISPL) consists of a graph G with arc weights, and a collection of source‐sink pairs with prescribed distances that do not necessarily conform to the shortest path lengths in G. The goal is to modify the arc weights, subject to a penalty on the deviation from the given weights, so that the shortest path lengths are equal to the prescribed values. We show that although ISPL is an NP‐hard problem, several ISPL classes are polynomially solvable. These cases include ISPL where the collection of the pairs share a single source and all other nodes as destinations (the single‐source all‐sink problem SAISPL). For the case where the collection contains a single node pair (the single‐source single‐sink problem SSISPL), we identify conditions on the uniformity of the penalty functions and on the original arc weights, which make SSISPL polynomially solvable. These results cannot be strengthened significantly as the general single‐source ISPL is NP‐hard and the all‐sink case, with more than one source, is also NP‐hard. We further provide a convex programming formulation for a relaxation of ISPL in which the shortest path lengths are only required to be no less than the given values (LBISPL). It is demonstrated how this compact formulation leads to efficient algorithms for ISPL. © 2009 Wiley Periodicals, Inc. NETWORKS, 2010