bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 3,3‐Dimethylglutamic Acid Derivatives as DPP‐IV Inhibitors and Evaluation of Their Chemical Stability
Authors: Hsu Tsu , Tsai Ting‐Yueh , Tseng Ya‐Ju , Chiou Mei‐Chun , Lu Cheng‐Tai , Chao Yu‐Sheng , Jiaang Weir‐Torn 
Published: October 2011

AbstractA novel five‐step synthesis of Boc‐3,3‐dimethylglutamic acid α‐ethyl ester 11 is reported. All the steps are high yielding and simple to carry out. By use of the 3,3‐dimethylglutamic acid building block, we successfully discovered a novel class of DPP‐IV inhibitors, Glu‐Pro‐Nitrile dipeptide mimics 2, with high potency (IC50 < 40 nM). The consequence of 3,3‐dimethyl substituent on the rate of intramolecular cyclization between N‐terminal amine and 5‐position amide bond in different buffer solutions was also evaluated.
Development of a Simple and Inexpensive Optical Absorption One‐Shot Sensor Membrane for Detection and Determination of Cyanide Ions in Water Samples
Authors: Chamjangali Mansour Arab , Soltanpanah Sepideh , Bagherian Ghadamali , Amin Amir Hossein 
Published: October 2011

AbstractA new one‐shot optical cyanide ion sensor is proposed for determination of cyanide ions. The sensor was constructed by immobilizing crystal violet (CV) on triacetylcellulose membrane. The sensing mechanism involves reaction between cyanide ions and the immobilized CV at pH = 5.4, which results in a decrease in absorbance of the membrane at 600 nm. The sensor shows sufficient repeatability, reproducibility, operational lifetime of 3 weeks, and a response of less then 10 min under the optimum conditions and response time of 8 min. Cyanide can be determined in the concentration range of 50.0‐800 μg mL‐1 with a detection limit of 5.0 μg mL‐1. Most ions do not interfere with the determination of cyanide ions. The proposed sensor was successfully applied to the determination of cyanide in spiked water samples.
Microwave‐assisted Friedländer Synthesis of Polysubstituted Quinolines Based on Poly(ethylene glycol) Bound Acetoacetate
Authors: Zhang Xiao‐Liang , Hu Qiao‐Sheng , Sheng Sheng‐Ri , Xiao Chen , Cai Ming‐Zhong 
Published: October 2011

AbstractPolysubstituted quinolines were efficiently prepared on the soluble polyethylene glycol (PEG) by microwave irradiation Friedländer condensation of PEG bound acetoacetate with 2‐aminoarylketones promoted by catalytic amount of polyphosphoric acid, and subsequently cleavage from the PEG with MeONa in MeOH. The polymer‐supported synthesis provided the target compounds in excellent yield and purity with a facile work‐up procedure.
Efficient Synthesis of the C1‐C9 Fragment of 7,8‐O‐Isopropylidene Protected Iriomoteolide 3a Derivative
Authors: Chang Ching‐Yao 
Published: October 2011

AbstractAn efficient and stereoselective synthesis of the C1‐C9 moiety of the 7,8‐O‐isopropylidene protected iriomoteolide 3a derivative has been accomplished. In our strategy, we employed olefin cross‐metathesis of the L‐(+)‐tartaric acid derivative (((4S,5S)‐2,2‐dimethyl‐5‐vinyl‐1,3‐dioxolan‐4‐yl)methoxy)(tert‐butyl)diphenylsilane with a synthesized methyl (S)‐3‐methylhex‐5‐enate to successfully provide the correct olefin geometry of the desired fragment.
Synthesis and Characterization of Two Novel Complexes of Cr(III) with Benzilmonoxime
Authors: Soleimani Esmaiel 
Published: October 2011

AbstractThe reaction of benzilmonoxime (BMOH) with CrCl3.6H2O in methanol gives the mono nuclear Cr(III) complex, [Cr(BMO)33 (1). Reaction of complex 1 with a methanolic solution of KOH at room temperature leads to a di‐nuclear Cr(III)‐Cr(III) complex, [Cr(BMO)2(OH)]2 (2). The complexes were characterized on the basis of their elemental analysis, Mass, IR, 1H and 13C‐NMR and electronic spectra. The IR studies were useful in assigning the coordination mode of the benzilmonoxime ligand to the chromium(III) ion. In addition, the presence of a hydroxo bridge in the dimeric complex 2 is inferred from the IR spectral studies. The electronic spectra of the complexes revealed two bands due to d–d transitions, and one band assignable to an oxygen (pπ)→Cr(eg*) LMCT transition observed in both complexes. An additional charge transfer transition, assignable to μ‐OH(pπ)→Cr(eg*), was only observed for the dimeric complex 2.The splitting energy and Racah parameter were calculated to be 18484 cm‐1 and 560 cm‐1 for [Cr(BMO)3] (1), 17986 cm‐1 and 545 cm‐1 for [Cr(BMO)2(OH)]2 (2) respectively.
Microwave‐Assisted Cross‐Coupling for the Construction of Diaryl Sulfides
Authors: Tan Chen‐Ming , Chen Grace Shiahuy , Chen Chien‐Shu , Chern Ji‐Wang 
Published: October 2011

AbstractThe construction of diaryl sulfides through the cross‐coupling of aryl iodides and thiols in microwave heating is described. By using this method, a variety of diaryl sulfides can be prepared in a mild condition and in high yields. Deactivated 4‐nitrothiophenol was effective to afford the product in 94% yield. Sterically hindered ortho‐substituted aryl iodides or thiophenols provided diaryl sulfides effectively by this microwave‐assisted coupling reaction.
Chemical composition, antioxidant and cytotoxicity activities of the essential oils of Myristica fragrans and Morinda citrifolia
Authors: Piaru Suthagar Pillai , Mahmud Roziahanim , Abdul Majid Amin Malik Shah , Ismail Sabariah , Man Che Nin 
Published: October 2011

AbstractBACKGROUND: In this study the chemical composition, antioxidant activities and cytotoxic effect of the essential oils of Myristica fragrans (nutmeg) and Morinda citrifolia (mengkudu) were determined.RESULTS: Thirty‐eight compounds in nutmeg oil and six compounds in mengkudu oil were identified by gas chromatography–mass spectrometry. The free radical scavenging activity of nutmeg oil was superior of that mengkudu oil. The MTT assay of nutmeg oil on human colorectal carcinoma (HCT‐116) and human breast carcinoma (MCF‐7) cell lines showed IC50 values of 78.61 and 66.45 µg mL−1, respectively. The mengkudu oil exhibited IC50 values of 91.46 and 78.15 µg mL−1 for HCT‐116 and MCF‐7, respectively.CONCLUSION: The results showed that nutmeg oil can be developed as potent anti‐cancer and antioxidant drugs. Copyright © 2011 Society of Chemical Industry
The effect of interfacial bonding on the elastic property of carbon nanotube‐reinforced composite
Authors: Maghamikia Sh. , Jam J. E. 
Published: October 2011

AbstractA micromechanics model is developed to calculate the effective elastic modulus of composite with aligned straight carbon nanotubes (CNTs). The interfacial bonding between CNTs and polymer matrix gives an important effect on reinforcing specification of CNTs. The nonlinear cohesive law is used to describe the interface debonding. The effect of debonding at CNTs/polymer interface and the van der Waal's (vdw) force between carbon atoms is studied on the mechanical properties of composite reinforced by CNTs. It is also shown that small CNTs have stronger reinforcing effect than larger ones. The debonded nanotubes behave like voids in the matrix and it can significantly reduce the stiffening effect of the nanocomposites. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers
Physical characterization of poly(glycerol sebacate)/Bioglass® composites
Authors: Liang Shuling , Cook Wayne D , Chen Qizhi 
Published: October 2011

AbstractDifferential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and X‐ray diffraction have been used to characterize the structure of a crosslinked polyester (poly(glycerol sebacate), PGS), prepared from a molar ratio of a diacid (sebacic acid) and a triol (glycerol), and their composites formed with an alkaline reactive filler, Bioglass®. The Bioglass reacts with the sebacic acid carboxylate groups during the composite synthesis, resulting in elastomers that are linked by ionic and covalent crosslinks. Due to its relatively low crosslink density, the unfilled PGS polymer can crystallize below room temperature but is an amorphous elastomer at room temperature. The DSC results show that the Bioglass composites are also semicrystalline below room temperature but the crystallinity is disrupted by the ionic linkages. DMTA of the dry PGS and PGS‐Bioglass composites confirms the semicrystalline nature of the materials and comparison with specimens that had been saturated with water vapour shows that the ionic crosslinks are dissociated by hydration by water molecules. Copyright © 2011 Society of Chemical Industry
Structural symmetry breaking of silicon‐containing poly(amide‐imide) oligomers and its relation to electrical conductivity and Raman‐active vibrations
Authors: González Henríquez Carmen M , Tagle Luis H , Terraza Claudio A , Barriga González Andrés , Volkmann Ulrich G , Cabrera Alejandro L , Ramos‐Moore Esteban , Pavez‐Moreno Maximiliano 
Published: October 2011

AbstractOptically active poly(amide‐imide) oligomers were synthesized by direct polycondensation between an aromatic diamine and a dicarboxylic acid both containing a diphenylsilylene unit. The reaction was carried out using triphenyl phosphite/pyridine in the presence of CaCl2 and N‐methyl‐2‐pyrrolidone as solvent. Oligomers were obtained in good yields and showed high solubility in common aprotic polar solvents. The precursors, monomers and poly(amide‐imide) oligomers were characterized using elemental analysis and Fourier transform infrared and NMR (1H, 13C, 29Si) spectroscopy. Additionally, the main vibrations of the functional groups (CO, CC or NH) in the oligomers with respect to temperature were characterized using Raman spectroscopy. The glass transition temperature was determined by studying the Raman spectra and corroborated using differential scanning calorimetry. The thermal stability was studied using thermogravimetric analysis. The molecular mass of the compounds was obtained from matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry and their optical properties were analyzed using UV‐visible diode array spectrophotometry. The electronic properties of the oligomers as well as the delocalization of charge carriers within their structures were analyzed using conductance‐voltage curves, which showed that these materials are excellent candidates for integrated optoelectronic applications. Copyright © 2011 Society of Chemical Industry
Water and sediment dynamics of penoxsulam and molinate in paddy fields: field and lysimeter studies
Authors: Kogan Marcelo , Araya Manuel , Alister Claudio 
Published: October 2011

AbstractBACKGROUND: In Chile, rice is cultivated under water‐seeded and continuously flooded conditions. Because herbicide dynamics in paddy fields and non‐flooded fields is different, 3 year experiments were performed to study the dissipation of molinate and penoxsulam in water and sediment.RESULTS: In field experiments, both herbicides dissipated by 45–55% from the initial applied amounts during the first 6 h after application in all crop seasons; in lysimeter experiments, dissipation amounts were approximately 10% for penoxsulam and 16% for molinate. Penoxsulam field water DT50 values varied from 1.28 to 1.96 days during the three study seasons, and DT90 values from 4.07 to 6.22 days. Molinate field water DT50 values varied from 0.89 to 1.73 days, and DT90 values from 2.82 to 5.48 days. Sediment residues were determined 2 days after herbicide application into the paddy water, and maximum concentrations were found 4–8 days after application. In sediment, DT50 values varied from 20.20 to 27.66 days for penoxsulam and from 15.02 to 29.83 days for molinate.CONCLUSIONS: Results showed that penoxsulam and molinate losses under paddy conditions are dissipated rapidly from the water and then dissipate slowly from the sediment. Penoxsulam and molinate field water dissipation was facilitated by paddy water motion created by the wind. Sediment adsorption and degradation are considered to have a secondary effect on the dissipation of both herbicides in paddy fields. Copyright © 2011 Society of Chemical Industry
Magnetism and magnetotransport in sputtered Co‐doped FeSi films
Authors: Morley Sophie A. , Porter Nicholas A. , Marrows Christopher H. 
Published: October 2011

AbstractFeSi is a non‐magnetic narrow‐gap semiconductor that can be doped n‐type by Co, which also gives rise to magnetic order. Here we report on the growth of sputtered thin films of Fe0.8Co0.2Si, which are predominantly ε ‐phase (B20 lattice structure), and possess that phase's characteristic magnetotransport properties. The ordinary Hall coefficient shows that each Co atom donates roughly one electron, whilst the magnetometry suggests that each gives rise to close to one Bohr magneton of moment. These results indicate that a highly spin‐polarised electron gas persists despite the inevitable disorder in these thin films, suitable for spintronic devices. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A vision guided hybrid robotic prototype system for stereotactic surgery
Authors: Wei Jun , Wang Tianmiao , Liu Da 
Published: October 2011

AbstractBackgroundRobot‐assisted surgery (RAS) systems help surgeons performing accurate operations, but a number of drawbacks render them not yet suitable for clinical theaters and procedures. In this paper, a novel vision guided robotic system is proposed to facilitate navigation procedures.MethodsA vision guided hybrid robotic system is designed, consisting of a passive serial arm and an active parallel frame. Navigation is accomplished in three steps: approaching, aiming and insertion. First, the target is safely approached with the passive arm. Second, the trajectory is automatically aligned using the parallel frame. And then the target is reached by manual insertion. A stereo camera is used to position fiducials, the robot and the surgical tool. It also provides working area images for professional surgeons at a remote site.ResultsThe prototype system accomplished phantom and animal trials with satisfactory accuracy. The robot can easily be adjusted to avoid obstacles and quickly set up on an optimal ‘approaching’ place. The surgical tool is automatically aligned with the trajectory. The system can withdraw from the working area and restore the aiming posture freely. With the help of the working area images, some important navigation steps can be handled remotely.ConclusionsA novel vision guided robotic system is proposed and validated. It enables surgeons to fit the system to the clinical theater. System safety and feasibility are enhanced by multi‐step navigation procedures and remote image monitoring. The system can be operated easily by general clinical staff. Copyright © 2011 John Wiley & Sons, Ltd.
Remote controlled robot assisted cardiac navigation: feasibility assessment and validation in a porcine model
Authors: Ganji Yusof , Janabi‐Sharifi Farrokh , Cheema Asim N. 
Published: October 2011

AbstractBackgroundDespite the recent advances in catheter design and technology, intra‐cardiac navigation during electrophysiology procedures remains challenging. Incorporation of imaging along with magnetic or robotic guidance may improve navigation accuracy and procedural safety. In the present study, the in vivo performance of a novel remote controlled Robot Assisted Cardiac Navigation System (RACN) was evaluated in a porcine model.MethodsThe navigation catheter and target sensor were advanced to the right atrium using fluoroscopic and intra‐cardiac echo guidance. The target sensor was positioned at three target locations in the right atrium (RA) and the navigation task was completed by an experienced physician using both manual and RACN guidance. The navigation time, final distance between the catheter tip and target sensor, and variability in final catheter tip position were determined and compared for manual and RACN guided navigation.ResultsThe experiments were completed in three animals and five measurements recorded for each target location. The mean distance (mm) between catheter tip and target sensor at the end of the navigation task was significantly less using RACN guidance compared with manual navigation (5.02 ± 0.31 vs. 9.66 ± 2.88, p = 0.050 for high RA, 9.19 ± 1.13 vs. 13.0 ± 1.00, p = 0.011 for low RA and 6.77 ± 0.59 vs. 15.66 ± 2.51, p = 0.003 for tricuspid valve annulus). The average time (s) needed to complete the navigation task was significantly longer by RACN guided navigation compared with manual navigation (43.31 ± 18.19 vs. 13.54 ± 1.36, p = 0.047 for high RA, 43.71 ± 11.93 vs. 22.71 ± 3.79, p = 0.043 for low RA and 37.84 ± 3.71 vs. 16.13 ± 4.92, p = 0.003 for tricuspid valve annulus. RACN guided navigation resulted in greater consistency in performance compared with manual navigation as evidenced by lower variability in final distance measurements (0.41 vs. 0.99 mm, p = 0.04).ConclusionThis study demonstrated the safety and feasibility of the RACN system for cardiac navigation. The results demonstrated that RACN performed comparably with manual navigation, with improved precision and consistency for targets located in and near the right atrial chamber. Copyright © 2011 John Wiley & Sons, Ltd.
Next‐generation treatment strategies for human papillomavirus‐related head and neck squamous cell carcinoma: where do we go?
Authors: Olthof Nadine C. , Straetmans Jos M.J.A.A. , Snoeck Robert , Ramaekers Frans C.S. , Kremer Bernd , Speel Ernst‐Jan M. 
Published: October 2011

SUMMARYOncogenic human papillomavirus (HPV) is currently recognised as a major risk factor for the development of head and neck squamous cell carcinomas (HNSCC). HPV is mostly detected in tumours arising from the oropharynx and more specifically from the tonsil. HPV‐related tumours display clinical and molecular characteristics that are distinct from HPV‐unrelated tumours, which are generally induced by alcohol and tobacco abuse. Detection of biologically active HPV in HNSCC has prognostic relevance, which warrants the separate classification of HPV‐induced tumours and is a prerequisite for further optimisation of treatment protocols for this distinct group. Current guidelines for the treatment of oropharyngeal squamous cell carcinoma (OPSCC) have not incorporated specific treatment modalities for HPV‐related tumours. The development of such treatment options is still in a preclinical phase or in early clinical trials. Recent data on treatment response of OPSCC have been obtained by retrospectively analysing HPV‐status and indicate that patients with HPV‐related tumours show a favourable prognosis, independent of the type of treatment. These patients may benefit from de‐intensified treatment, which should be assessed in prospective clinical trials. The development and future use of new antiviral and immunomodulatory therapeutics may be instrumental in this approach to improve survival rates and decrease disease‐and‐treatment‐related morbidity. In this review we will focus on present therapeutic HPV‐targeting strategies and discuss future directions for de‐intensified treatment of HPV‐positive HNSCC. Copyright © 2011 John Wiley & Sons, Ltd.
An RFID system yoking‐proof protocol conforming to EPCglobal C1G2 standards
Authors: Chen Chin‐Ling , Wu Chun‐Yi 
Published: October 2011

ABSTRACTAs radio‐frequency identification (RFID) can quickly identify an object without requiring physical contact, it provides efficient identification for the verification of individual objects. There are currently numerous practical applications for RFID systems in various domains. For example, RFID mechanisms can be used to check whether large quantities of goods are present within a supply‐chain system. Similarly, information about a product can be acquired in a supermarket without asking the clerks for help. The aforementioned applications are limited with regard to authentication between a single tag and a server, but other applications focus on authenticating the relationships among the tags. For example: a passenger carries a package while boarding an airplane. An airline agent has to check whether or not the package and the boarding card are correct and if the package corresponds to the boarding card. In this paper, we use a yoking‐proof mechanism conforming to EPCglobal Class 1 Generation 2 standards to solve this double problem. In addition, the proposed scheme can provide a convenient, low‐cost, and improved security mechanism for identifying the simultaneous presence of tags. Copyright © 2011 John Wiley & Sons, Ltd.
Patient aspects: A review of fifty-eight Danish HTA reports
Authors: Hansen Helle Ploug , Lee Anne , van Randwijk Christian Balslev 
Published: October 2011

Objectives: The objective of this study is to describe how patient aspects are assessed in Danish HTA reports, thereby contributing to the ongoing international debates concerning patient aspects in HTAs.Methods: Fifty-eight Danish HTA reports published from 1999 to 2010 were read systematically, focusing on the inclusion of patient aspects, the methods used to generate data, and if and how clinical recommendations concerning patient aspects were drawn.Results: Most of the fifty-eight HTA reports had a separate chapter about patient aspects. All reports included literature reviews for patient aspects. There was, however, much variation in the ways in which the authors presented and discussed their review methods. The most frequently used databases for the literature search were medical and HTA databases. More than half of the reports included primary research, either quantitative or qualitative methods, a few used both kinds of methods. Whereas some mentioned the importance of including patient aspects in daily clinical practice, others provided ideas on how to improve patient information or recommended changes in healthcare practices.Conclusions: Danish HTA reports do, to a large extent, include patient aspects in the assessment and in the final conclusions of the reports. If health policy and decision making is to be patient-focused, it is important that HTAs in the future integrate patient aspects in recommendations of HTA. Further improvement in assessments of patient aspects, in relation to use and description of methodologies and theoretical considerations, will assist producing the relevant evidence for these recommendations.
Counting Certain Pairings in Arbitrary Groups
Authors: HAMIDOUNE Y. O. 
Published: October 2011

In this paper, we study certain pairings which are defined as follows: if A and B are finite subsets of an arbitrary group, a Wakeford–Fan–Losonczy pairing from B onto A is a bijection φ : B → A such that bφ(b) ∉ A, for every b ∈ B. The number of such pairings is denoted by μ(B, A).We investigate the quantity μ(B, A) for A and B, two finite subsets of an arbitrary group satisfying 1 ∉ B, |A| = |B|, and the fact that the order of every element of B is ≥ |B| + 1. Extending earlier results, we show that in this case, μ(B, A) is never equal to 0. Furthermore we prove an explicit lower bound on μ(B, A) in terms of |B| and the cardinality of the group generated by B, which is valid unless A and B have a special form explicitly described. In the case A = B, our bound holds unless B is a translate of a progression.
Who's mind is it anyway?
Authors: Bowis John 
Published: October 2011

SummaryAs UK Health Minister John Bowis knew the challenges, the progress and the disasters of mental health provision and policy. He learned from service users, carers and practitioners that reality was usually different from theory. He came to believe a new structure was necessary to give patients a one-stop shop of care and treatment, that patients should be more involved in decisions that affect them and that stigma must be tackled by education and by wider understanding of services and crisis management. He now campaigns in the European Parliament and in many parts of the world for mental health to be higher on national agendas and to be based on effective and humane policies that ensure the appropriate treatment is provided and provided with dignity”Declaration of Interest: none