bluuebunny/crossref_metadata_2025 huggingface dataset:
Epoxidation of 4‐Alkylidenecyclopentenones: A Route to the 1‐Oxaspiro[2.4]hept‐6‐en‐5‐one Framework
Authors: Ahmar Mohammed , Thomé Stéphane , Cazes Bernard
Published: October 2012

Thanks to their lack of polarity, the exocyclic double bonds of 4‐alkylidenecyclopentenones 4 are selectively epoxidized by MCPBA to give spiroepoxycyclopentenones 7, which feature the nonclassical 1‐oxaspiro[2.4]hept‐6‐en‐5‐one framework. Under acidic conditions, compounds 7 undergo ring‐opening to afford 4‐hydroxy‐4‐(1‐hydroxyalkyl)cyclopentenones 10.
The Proton Sponge Effect: Substitution of Quino[7,8‐h]quinoline and the First Structurally Characterised Derivatives
Authors: Shaffer Karl J. , Parr Daniel C. , Wenzel Marco , Rowlands Gareth J. , Plieger Paul G.
Published: October 2012

A new route to unsymmetrical derivatives of quino[7,8‐h]quinoline was developed. Substitutions at the 2,11‐, 4,9‐ and 6,7‐positions of quino[7,8‐h]quinoline were also successfully performed. X‐ray crystal structure determinations of the resulting products revealed the propensity for derivatives of this molecule to exist in either stabilised keto or imino forms as a result of the formation of a strong intramolecular N–H···N hydrogen bond.
Direct and Stereoselective Alkylation of Nitro Derivatives with Activated Alcohols in Trifluoroethanol
Authors: Petruzziello Diego , Gualandi Andrea , Grilli Stefano , Cozzi Pier Giorgio
Published: October 2012

Herein we disclose the simple, effective, and practical alkylation of nitroalkanes that takes place with benzylic, benzhydrylic, and propargylic alcohols in trifluoroethanol. A variety of different nitroalkanes bearing functional groups can be used in this SN1‐type reaction to afford the desired products in quantitative yields. Different chiral nitro derivatives were submitted to this highly diastereoselective alkylation reaction with selected benzhydrols. A new, effective, and chiral pyrrolidine organocatalyst was prepared by using this methodology.
Assessment of Cell Viability Using the Chronoamperometric Method Based on Screen‐Printed Electrodes
Authors: Tsai Hweiyan , Tsai Shang‐heng , Deng Hwei‐wen , Bor Fuh C.
Published: October 2012

This study investigates suitable electrochemical mediators and optimal mediator concentration for breast cancer cells, MDA‐MB‐231. The optimized mediators were 1 mM ferricyanide and 10 µM menadione. The specifications for the chronoamperometric detection of ferrocyanide were a linear range of 0.02–0.36 mM. The detection limit was 5.0 µM and the spiked recovery was 95 %–99 %. The oxidation currents increased linearly with cultured cell density. Cell viabilities determined using electrochemical methods confirmed those determined by MTT assay. The running time can be reduced to less than 30 min. The chronoamperometric method can be used as an alternative method for rapidly assessing the viability of breast cancer cells.
Highly Stable Polymeric Ionic Liquid Modified Electrode to Immobilize Ferricyanide for Electroanalysis of Sulfide
Authors: Chang Jen‐Lin , Wei Guor‐Tzo , Chen Tsu‐Yin , Zen Jyh‐Myng
Published: October 2012

We report here the preparation and application of a highly stable polymeric ionic liquid‐modified electrode to immobilize ferricyanide for sulfide analysis. Good long‐term stability of the modified electrode verifies its potential in sensor applications. The electrocatalytic sulfide oxidation signal at ∼0.0 V vs. Ag/AgCl in pH 7 PBS at the modified electrode was used for sulfide detection by hydrodynamic chronoamperometry and a detection limit of 12.9 nM (S/N=3) was obtained. Practical utility of the system is applied to the determination of sulfide content in hot spring water and ground water.
Carbon Cloth/Carbon Nanotube Electrodes for Biofuel Cells Development
Authors: Haddad Raoudha , Xia Wei , Guschin Dmitrii A. , Pöller Sascha , Shao Minling , Vivekananthan Jeevanthi , Muhler Martin , Schuhmann Wolfgang
Published: October 2012

Carbon nanotubes (CNTs) grown on carbon cloth substantially increased the surface area of the electrodes. Carbon cloths were pretreated with HNO3 vapor before CNTs growth and electrochemically oxidized afterwards. The CNT‐modified carbon cloths were characterized using scanning electron microscopy, Raman spectroscopy, cyclic voltammetry and electrochemical impedance spectroscopy. Biofuel cells based on these CNT‐modified electrode materials using Laccase from Trametes hirsuta and cellobiose dehydrogenase from Myriococcum thermophilium entrapped in specifically designed Os‐complex modified redox polymers showed a power density of 5.87 µW/cm2 which is 125 fold enhanced as compared with electrodes prepared on untreated carbon cloth.
Different strategies for the preconcentration and separation of parabens by capillary electrophoresis
Authors: Maijó Irene , Borrull Francesc , Aguilar Carme , Calull Marta
Published: October 2012

Several strategies, namely, large volume sample stacking (LVSS), field‐amplified sample injection (FASI), sweeping, and in‐line SPE‐CE, were investigated for the simultaneous separation and preconcentration of a group of parabens. A BGE consisting of 20 mM sodium dihydrogenphosphate (pH 2.28) and 150 mM SDS with 15% ACN was used for the separation and preconcentration of the compounds by sweeping, and a BGE consisting of 30 mM sodium borate (pH 9.5) was used for the separation and preconcentration of the compounds by LVSS, FASI, and in‐line SPE‐CE. Several factors affecting the preconcentration process were investigated in order to obtain the maximum enhancement of sensitivity. The LODs obtained for parabens were in the range of 18–27, 3–4, 2, and 0.01–0.02 ng/mL, and the sensitivity evaluated in terms of LODs was improved up to 29‐, 77‐, 120‐, and 18 400‐fold for sweeping, LVSS, FASI, and in‐line SPE‐CE, respectively. These preconcentration techniques showed potential as good strategies for focusing parabens. The four methods were validated with standard samples to show the potential of these techniques for future applications in real samples, such as biological and environmental samples.
Fabrication of a magnet‐assisted alignment device for the amperometric detection of capillary electrophoresis using a carbon nanotube/polypropylene composite electrode
Authors: Xu Junchao , Zhang Luyan , Chen Gang
Published: October 2012

A magnet‐assisted alignment device was designed and fabricated for the amperometric detection of CE. It mainly consisted of a magnet‐containing electrode holder, a capillary‐based microdisc detection electrode, a detection cell, and a micrometer adjuster. To demonstrate the feasibility and performance of the alignment device, it was used in combination with a carbon nanotube/polypropylene (CNT/PP) composite electrode for the determination of p‐phenylenediamine, m‐aminophenol, and m‐dihydroxybenzene in commercial hair dye by CE. The CNT‐based electrode was fabricated by packing a melt mixture of CNTs and PP in a piece of fused silica capillary under heat, offering significantly lower operating potentials, substantially enhanced signal‐to‐noise characteristics, and high resistance to surface fouling. Because magnetic force was employed to move the detection electrode, the alignment system was significantly simplified. It is characterized by simple design and fabrication, high alignment reproducibility, reduced alignment time, and low cost. Both the alignment device and the CNT/PP composite electrode should find a wide range of applications in microchip CE, flowing injection analysis, and other microfluidic analysis systems.
A probabilistic performance‐based approach for mitigating the seismic pounding risk between adjacent buildings
Authors: Barbato M. , Tubaldi E.
Published: October 2012

Existing design procedures for determining the separation distance between adjacent buildings subjected to seismic pounding risk are based on approximations of the buildings' peak relative displacement. These procedures are characterized by unknown safety levels and thus are not suitable for use within a performance‐based earthquake engineering framework.

This paper introduces an innovative reliability‐based methodology for the design of the separation distance between adjacent buildings. The proposed methodology, which is naturally integrated into modern performance‐based design procedures, provides the value of the separation distance corresponding to a target probability of pounding during the design life of the buildings. It recasts the inverse reliability problem of the determination of the design separation distance as a zero‐finding problem and involves the use of analytical techniques in order to evaluate the statistics of the dynamic response of the buildings. Both uncertainty in the seismic intensity and record‐to‐record variability are taken into account.

The proposed methodology is applied to several different buildings modeled as linear elastic single‐degree‐of‐freedom (SDOF) and multi‐degree‐of‐freedom (MDOF) systems, as well as SDOF nonlinear hysteretic systems. The design separation distances obtained are compared with the corresponding estimates that are based on several response combination rules suggested in the seismic design codes and in the literature. In contrast to current seismic code design procedures, the newly proposed methodology provides consistent safety levels for different building properties and different seismic hazard conditions. Copyright © 2012 John Wiley & Sons, Ltd.
Design method and behavior factor for steel frames with buckling restrained braces
Authors: Bosco Melina , Marino Edoardo M.
Published: October 2012

Buckling restrained braces (BRBs) are very effective in dissipating energy through stable tension–compression hysteretic cycles and have been successfully experimented in the seismic protection of buildings. Their behavior has been studied extensively in the last decades and today the level of performance guaranteed by these devices and the technological constrains that have to be fulfilled to optimize their behavior are well known. Furthermore, several companies in the world have developed their own BRBs and are now producing them. In spite of this, many seismic codes (for instance, the EuroCode 8) do not stipulate provisions for the design and construction of earthquake‐resistant structures equipped with BRBs. This discourages the structural engineering community from using these devices and seriously limits their use in structural applications. In this paper a procedure for the seismic design of steel frames equipped with BRBs is proposed. Furthermore, the paper presents a numerical investigation aimed at validating this design procedure and proposing the value of the behavior factorqthat should be used for this structural type. To this end, a set of frames with BRBs is first designed by means of several values ofq. Then, the obtained frames are subjected to a set of accelerograms compatible with the elastic response spectrum considered in design. The seismic response of the frames is determined by nonlinear dynamic analysis and represented in terms of the ductility demand of BRBs and the internal force demand of nondissipative members (beams and columns). Finally, the largest value ofqthat leads to acceptable seismic performance of the analyzed frames is assumed as adequate. The value ofqis given in the paper as a continuous function of the assumed ductility capacity of the BRBs. Copyright © 2012 John Wiley & Sons, Ltd.
A simple strategy to identify acute hepatitis C virus infection among newly incarcerated injection drug users
Authors: Kim Arthur Y. , Nagami Ellen H. , Birch Christopher E. , Bowen Melinda J. , Lauer Georg M. , McGovern Barbara H.
Published: October 2012

Acute hepatitis C virus (HCV) infection is underdiagnosed because most patients are asymptomatic. The majority of new infections occur among people who inject drugs (PWID), many of whom have a history of incarceration. In a previous pilot study, we identified symptomatic HCV cases, mainly among Caucasian inmates. We designed a cross-sectional study to evaluate whether risk factor–based screening of newly incarcerated inmates would enhance identification of asymptomatic acute HCV infection and elucidate any demographic shifts in HCV acquisition. From October 2006 to March 2008, 6,342 inmates underwent health assessments and 3,470 inmates (55%) were screened. The racial distribution was as follows: African American, 24.0%; Caucasian, 49.5%; Hispanic, 22.2%. One hundred seventy-one inmates (4.9%) were classified as high-risk. After further evaluation, 35 (20.5%) inmates were diagnosed with acute HCV with a mean age of 29 years; 62.9% were female and 91% were Caucasian. No African Americans were diagnosed with acute HCV. Our case-finding rate was 1.9 patients/month nearly a three-fold increase compared with our historical control period with a higher proportion of asymptomatic cases. We estimate a prevalence of ˜1.0% (95% confidence interval, 0.7%-1.4%) of acute HCV infections among newly incarcerated inmates.

Conclusion
: Within the correctional system, systematic screening based on risk factors successfully identifies acute HCV infection among PWID, including asymptomatic patients. Our data also reflect changing nationwide patterns of injection drug use that vary by age, ethnicity, and race, leading to a marked reduction of acute HCV infections among African Americans compared with non-Hispanic whites. The nationwide implementation of this simple low-cost strategy in prison-based settings could identify more than 7,000 acute HCV infections among PWID, provide insight into changing epidemiologic trends, and facilitate appropriate therapeutic and preventive interventions. (Hepatology 2013)
Isolated human/animal stratum corneum as a partial model for 15 steps in percutaneous absorption: emphasizing decontamination, Part I
Authors: Hui Xiaoying , Lamel Sonia , Qiao Peter , Maibach Howard I.
Published: October 2012

Since the advent of World War II, governments and laboratories have made a concerted effort to improve prophylactic and therapeutic interventions counteracting cutaneously directed chemical warfare agents (CWA), and by inference, common industrial and consumer dermatotoxicants. In vitro percutaneous penetration assays, first utilized by Tregear in the 1940s and presently in various modifications, have been fundamental to this effort. Percutaneous penetration, often considered a simple one‐step diffusion process, consists of at least 15 steps. The first part of this review covers the initial steps related to absorption and excretion kinetics, vehicle characteristics, and tissue disposition. Importantly, the partitioning behavior and stratum corneum (SC) diffusion by a wide physicochemical array of compounds shows that many compounds have similar diffusion coefficients determining their percutaneous absorption in vivo. After accounting for anatomical SC variation, the penetration flux value of a substance depends mainly on its SC/vehicle partition coefficient. Additionally, the SC acts as a ‘reservoir’ for topically applied molecules and application of tape stripping has been found to quantify the chemical remaining in the SC which can predict total molecular penetration in vivo. Decontamination is of particular concern and even expediting standard washing procedures after dermal chemical exposure often fails to remove chemicals. This overview summarizes knowledge of percutaneous penetration extending insights into the complexities of penetration, decontamination and potential newer assays that may be of practical importance. Copyright © 2012 John Wiley & Sons, Ltd.
Establishment of transactivation assay systems using fish, amphibian, reptilian and human thyroid hormone receptors
Authors: Oka Tomohiro , Mitsui‐Watanabe Naoko , Tatarazako Norihisa , Onishi Yuta , Katsu Yoshinao , Miyagawa Shinichi , Ogino Yukiko , Yatsu Ryohei , Kohno Satomi , Takase Minoru , Kawashima Yukio , Ohta Yasuhiko , Aoki Yasunobu , Guillette Louis J. , Iguchi Taisen
Published: October 2012

Thyroid hormones are essential for the regulation of a wide range of biological processes associated with normal development and metabolism in vertebrates. For the screening of chemicals with a potential thyroid hormone and anti‐thyroid hormone activities, we have established transient transactivation assay systems using thyroid hormone receptors (TRα and TRβ) from three frog species (Xenopus laevis, Silurana tropicalis and Rana rugosa), a fish (Oryzias latipes), an alligator (Alligator mississippiensis) and a human (Homo sapiens). In all species examined, similar transcriptional activities were found for triiodothyronine (T3: 10–11 M in TRα and 10–10 M in TRβ) and thyroxine (T4: 10–9 M in TRα and 10–8 M in TRβ). Analogs of thyroid hormone (3,5,3′,‐triiodothyroacetic acid and 3,3′,5,5′‐tetraiodothyroacetic acid) exhibited weaker activity, requiring 10‐fold higher concentrations for induction of activity when compared with T3 and T4. These results provide support for the usefulness of in vitro screening assay systems as part of an approach to test chemicals for potential thyroid hormone receptor activity. In addition, we observed that T3‐stimulated transcriptional activity of the O. latipes TRα was inhibited by 10–5 M tetrabromobisphenol A (TBBPA). In contrast, TR antagonist activities on TRα were not encountered in other species, even with TBBPA concentrations at 10–5 M. In vitro transactivation assay systems using TRs from various species can be used for the screening of chemicals with thyroid‐receptor agonist and antagonist activities. They also can be used for studies that examine evolutionary differences among species in the potency of TR activation. Copyright © 2012 John Wiley & Sons, Ltd.
Involvement of the p38 MAPK signaling pathway in S‐phase cell‐cycle arrest induced by Furazolidone in human hepatoma G2 cells
Authors: Sun Yu , Tang Shusheng , Jin Xi , Zhang Chaoming , Zhao Wenxia , Xiao Xilong
Published: October 2012

Given the previously described essential role for the p38 mitogen‐activation protein kinase (p38 MAPK) signaling pathway in human hepatoma G2 cells (HepG2), we undertook the present study to investigate the role of the p38 MAPK signaling pathway in cell‐cycle arrest induced by Furazolidone (FZD). The aim of this study was to determine the effects of FZD on HepG2 cells by activating and inhibiting the p38 MAPK signaling pathway. The cell cycle and proliferation of HepG2 cells treated with FZD were detected by flow cytometry and MTT assay in the presence or absence of p38 MAPK inhibitors (SB203580), respectively. Cyclin D1, cyclin D3 and CDK6 were detected by quantitative real‐time PCR and western blot analysis. Our data showed that p38 MAPK became phosphorylated after stimulation with FZD. Activation of p38 MAPK could arise S‐phase cell‐cycle arrest and suppress cell proliferation. Simultaneously, inhibition of the p38 MAPK signaling pathway significantly prevented S‐phase cell‐cycle arrest, increased the percentage of cell viability and decreased the expression of cyclin D1, cyclin D3 and CDK6. These results demonstrated that FZD arose S‐phase cell‐cycle arrest via activating the p38 MAPK signaling pathway in HepG2 cells. Cyclin D1, cyclin D3 and CDK6 are target genes functioning at the downstream of p38 MAPK in HepG2 cells induced by FZD. Copyright © 2012 John Wiley & Sons, Ltd.
Conventional and Microwave‐Assisted Synthesis of Benzimidazole Derivatives and Their In Vitro Inhibition of Human Cyclooxygenase
Authors: Secci Daniela , Bolasco Adriana , D'Ascenzio Melissa , della Sala Flavio , Yáñez Matilde , Carradori Simone
Published: October 2012

A large series of 1,2‐diaryl‐benzimidazole and 2‐aryl‐1H‐benzimidazole derivatives were synthesized with slight differences using both microwave irradiation and conventional heating methods. Usually higher yields and time reactions reduction were obtained with the former method. All compounds were assayed for their in vitro ability to inhibit human cyclooxygenases, and most of them showed an encouraging inhibitory activity and isoform selectivity in the micromolar range.
Regioselective Synthesis of Natural 6‐Prenylpolyhydroxyisoflavone (Lupisoflavone) and Lupisoflavone Hydrate with Hypervalent Iodine Reagents
Authors: Hossain Mohammad Mamun
Published: October 2012

The Pd(0)‐catalyzed coupling reaction of 6‐iodotetraalkoxyisoflavone, which was obtained from the oxidative rearrangement of 3′‐iodotetraalkoxychalcones, with 2‐methyl‐3‐butyn‐2‐ol in heating condition affords 6‐alkynylisoflavone. Hydrogenation of 6‐iodotetraalkoxyisoflavone followed by acid‐catalyzed dehydration with p‐TsOH·H2O gave lupisoflavone.
Formylation of 4,7‐Dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidines Using Vilsmeier–Haack Conditions
Authors: Lipson Victoria V. , Svetlichnaya Nataliya V. , Borodina Victoria V. , Shirobokova Maria G. , Desenko Sergey M. , Musatov Vladimir I. , Shishkina Svetlana V. , Shishkin Oleg V. , Zubatyuk Roman I.
Published: October 2012

Formylation of 5‐methyl‐7‐phenyl‐4,7‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidine 1a using Vilsmeier–Haack conditions yields 5‐methyl‐7‐phenyl‐4,7‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidin‐6‐ylcarbaldehyde 3a. 5,7‐Diaryl‐4,7‐dihydro‐1,2,4‐triazolo[1,5‐a]pyrimidines 1b, 1c in this reaction apart from formylation undergo recyclization into 5‐aryl‐1,2,4‐triazolo[1,5‐a]pyrimidin‐6‐ylmethane derivatives 4b, 4c, 5b, 5c, and 6. The structure of the synthesized compounds was determined on the basis of NMR, IR, and MS spectroscopic data and confirmed by the X‐ray analysis of the 6‐(ethoxy‐phenyl‐methyl)‐5‐phenyl‐[1,2,4]triazolo[1,5‐a]pyrimidine 6, 5‐phenyl‐6‐(1‐phenyl‐vinyl)‐[1,2,4]triazolo[1,5‐a]pyrimidine 11, and 7‐phenyl‐6‐(1‐phenyl‐vinyl)‐[1,2,4]triazolo[4,3‐a]pyrimidine 12.
Synthesis and Antimicrobial Activity of New Thiazole Derivatives and Their Glucoside and Acyclic Nucleoside Analogs
Authors: Ali Omar M. , El‐Sayed Wael A. , El‐Sayed Heba A. , Abdel‐Rahman Adel A.‐H.
Published: October 2012

New thiazole derivatives were synthesized. The N‐substituted acyclic nucleoside analogs and the substituted glucosides were also prepared. The synthesized compounds were tested for their antimicrobial activity against Candida albicans, Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The obtained results indicated that most of the tested compounds exhibited low to high moderate activities whereas few compounds were found to exhibit little or no activity against the tested microorganisms.
Synthesis and Structure of Novel 4‐Arylamino‐2‐phenyl‐6‐substituted‐quinazoline
Authors: Xing Zhi‐Yong , Fu Ying , Ye Fei
Published: October 2012

A series of quinazoline derivatives were synthesized via the cyclization of N, N′–disubstituted thiourea derivatives in the mixed solvent of acetontrile and aqueous NaOH by ultraviolet light irradiation. All the compounds are characterized by IR, 1HNMR, 13CNMR, MS, and element analysis. The absolute configurations of 3a was determined by X‐ray crystallography.
Solvent‐Free Synthesis of 2‐(Phenylamino)‐4‐(trifluoromethyl)‐1,6‐dihydropyrimidine Derivatives Catalyzed by Sulfamic Acid
Authors: Shen Shide , Yang Weihua , Yu Chenxia , Li Tuanjie , Yao Changsheng
Published: October 2012

A series of 2‐(phenylamino)‐4‐(trifluoromethyl)‐1,6‐dihydropyrimidine derivatives were synthesized efficienly via the reaction of aryl aldehyde, ethyl 4,4,4‐trifluoro‐3‐oxobutanoate and 1‐phenylguanidine carbonate catalyzed by sulfamic acid under solvent‐free conditions. This protocol has the advantages of mild condition, high yields and environmentally benign procedure.
Synthesis and Antimicrobial Activities of New Polyhalogenated Benzimidazoles
Authors: Laudy Agnieszka E. , Moo‐Puc Rosa , Cedillo‐Rivera Roberto , Kazimierczuk Zygmunt , Orzeszko Andrzej
Published: October 2012

A series of new polyhalogenated benzimidazoles has been synthesized and their antibacterial and antiprotozoal activity was evaluated. Several of new substituted halogenobenzimidazoles and their 2′‐deoxynucleosides showed noteworthy antiprotozoal toxicity particularly against Giardia lamblia. The most potent agents against bacteria and fungi were 4,5,6,7‐tetrachlorobenzimidazoles with polyfluoroalkyl chain at position 2 of the heterocyclus.
Synthesis of New Chiral and Racemic 1,3‐Dioxolanes
Authors: Küçük Hatice Başpınar , Yusufoğlu Ayşe
Published: October 2012

A series of chiral 1,3‐dioxolanes, 3–12, with >99% ee values, have been synthesized. This is the first study of chiral ketalization reaction starting from ketones with aryl, monosubstituted aryl, and long alkyl chains (C11—AC13). Their ee values were determined by chiral high‐performance liquid chromatography (HPLC) on Chiralcel OD column, using their racemic 1,3‐dioxolanes rac‐3–12, which were also synthesized for the first time. These chiral and racemic 1,3‐dioxolanes were characterizated by infrared, NMR (1H, 13C), mass spectrometry, elemental analysis, optical rotation, and chiral HPLC.
A Simple and Convenient Synthesis of 4‐Ylidene‐5(4H)oxazolone Derivatives: Oxazolone Ring Transformation Leading to Other Heterocyclic Structures
Authors: Abdel‐Motaleb Ramadan M. , Bakeer Hadeer M. , Tamam Gammal H. , Arafa Wael A. A.
Published: October 2012

Simple, effective, and high yield synthetic procedure for the synthesis of 4‐ylidene‐5(4H)‐oxazolones 2a–m from arylidene‐malononitriles under solvent‐free conditions is described. The scope of this reaction was investigated, and it was found that the presence of anhydrous sodium acetate gave the corresponding oxazolones in excellent yields. The newly generated oxazolone derivative 2m underwent ring transformation into pyrroles, imidazoles, pyridazine, and triazines.
Synthesis of Some Series of 1,3‐Thiazolidin‐4‐ones and Indoles Incorporating Furoxan Moiety Starting with Anethole Isolated from Star Anise Oil
Authors: Dinh Nguyen Huu , Trung Nguyen Quang , Dat Nguyen Dang , Hien Nguyen
Published: October 2012

Some series of 1,3‐thiazolidin‐4‐ones and indoles incorporating furoxan moiety were synthesized from anethole, a main component of star anise oil. The structure of these compounds and the intermediates was examined by elemental and spectral data. Ten compounds were screened against some bacteria and fungi.
Synthesis of Indeno[2′,1′:5,6]pyrido[2,3‐d]pyrimidine Derivatives and Their Recognition Properties as New Type Anion Receptors
Authors: Shi Da‐Qing , Li Yan , Wang Hai‐Ying
Published: October 2012

A new type anion receptors containing indeno[2′,1′:5,6]pyrido[2,3‐d]pyrimidine have been synthesized via three‐component reaction of aldehyde, 6‐aminopyrimidine‐2,4‐dione, and 1,3‐indanedione in aqueous media. The binding properties of the receptors with anions such as F−, Cl−, Br−, AcO−, HSO4−, and H2PO4− have been investigated by UV–vis spectroscopy methods. The results have shown that receptors have good selectivity to F− and AcO−, and a 1:1 stoichiometry complex has been formed between compounds and anions.
Reaction with Hydrazonoyl Halides 64: Synthesis of Some New Triazolino[4,3‐a]pyrimidines, 1,3,4‐Thiadiazoles, and 5‐Arylazothiazoles
Authors: Abdelhamid Abdou O. , Fahmi Abdelgawad A. , Baaui Basma S.
Published: October 2012

2,3‐Dihydro‐1,3,4‐thiadiazoles, 2,3‐dihydro‐1,3,4‐selenadiazoles, and triazolino[4,3‐a]pyrimidines containing benzofuran moiety were prepared from the reaction of 2‐(2‐phenylhydrazono)‐1‐(5‐bromobenzofuran‐2‐yl)‐2‐chloroethanone with each of potassium thiocyanate, potassium selenocyanate, alkyl carbodithioate, and pyrmidine‐2‐thione derivatives. All the newly synthesized compounds were confirmed by elemental analysis, spectral data, and alternative route synthesis whenever possible.
Syntheses, Crystal Structures, and Spectral Characterization of Three New Asymmetrical Substituted Triaryltriazoles
Authors: Zhao Jian , Shen Guo‐Ping , Zhang Yu , Shen Xuan , Zhu Dun‐Ru
Published: October 2012

Triaryltriazoles are of interest in iron(II) complexes designed to study spin‐crossover properties. In this study, three new asymmetrical substituted triaryltriazoles, 3‐(p‐R‐phenyl)‐4‐(p‐chlorophenyl)‐5‐(2‐pyridyl)‐1,2,4‐triazoles (R = OCH3, 5a; Cl, 5b; Br, 5c), were successfully synthesized from 2‐picolinic acid by a three‐step reaction through an intermediate N‐(p‐R‐phenylcarbonyl)‐N′‐(2‐pyridylcarbonyl)hydrazine (4a–4c). Yield of 5a–5c is in the range from 74 to 87%. The compounds 5a–5c were characterized by UV, FTIR, 1H‐NMR, electrospray ionization mass spectrum spectra, and elemental analysis. Additionally, the absolute configurations of 5a–5c were determined by single crystal X‐ray crystallography.
One‐Pot Microwave‐Assisted Synthesis of Novel Substituted N‐Dichloroacetyl‐4,5‐dimethyl‐1,3‐oxazolidines
Authors: Fu Ying , Yang Lei , Ye Fei , Gao Shuang
Published: October 2012

A one‐pot and efficient synthesis of substituted N‐dichloroacetyl‐4,5‐dimethyl‐1,3‐oxazolidines utilizing the reaction of alkamine with aldehyde or ketone in refluxing benzene under microwave irradiation was described. The N‐acylation was followed with dichloroacetyl chloride and NaOH acting as the attaching acid agent. All compounds were characterized by IR, 1H NMR, 13C NMR, and element analysis. Additionally, the absolute configuration of 4a was determined by X‐ray crystallography. All the compounds were tested for their herbicide safeners activity of protecting the maize from the injury of acetochlor.
An Efficient Method for the Synthesis of 3‐Aryl‐4,7‐phenanthroline Derivatives Catalyzed by Iodine
Authors: Yin Ming‐Yue , Zhang Mei‐Mei , Wang Wei , Li Yu‐Ling , Wang Xiang‐Shan
Published: October 2012

A mild and efficient method for the synthesis of 3‐aryl‐4,7‐phenanthroline derivativesviathree‐component reaction of aromatic aldehyde, quinolin‐6‐amine, andn‐butylvinyl ether is described using iodine as catalyst. The features of this procedure are mild reaction conditions, good to high yields, and operational simplicity.
Synthesis and Anti‐Avian Influenza Virus (H5N1) Evaluation of Some Novel Nicotinonitriles and Their N‐Acylic Nucleosides
Authors: Rashad Aymn E. , Shamroukh Ahmed H. , El‐Hashash Maher A. , El‐Farargy Ahmed F. , Yousif Nabil M. , Salama Mowafia A. , Mostafa Ahmed , El‐Shahat Mahmoud
Published: October 2012

Pyridine and fused pyridines derivatives are interesting compounds with diverse chemical properties and pharmacological activities. Herein, the synthesis and antiviral evaluation of some new pyridines are described.
Synthesis and Insecticidal Activities of Chlorothiazolyl Analogs of Nitromethylene Neonicotinoids with Tetrahydropyridine Fixed cis‐Configuration
Authors: Shao Xusheng , Huang Xinglong , Shi Qian , Li Zhong , Tao Liming , Song Gonghua
Published: October 2012

The chlorothiazolyl moiety was an effective bioisoster of chloropyridyl in pesticide molecular design. Replacement of chloropyridyl in cis‐nitromethylene neonicotinoids with chlorothiazolyl generated the chlorothiazolyl counterpart of nitromethylene neonicotinoids with tetrahydropyridine fixed cis‐configuration. Bioassay against cowpea aphis (Aphis craccivora) indicated that the chlorothiazolyl analogs could maintain the high insecticidal activity.
High Yield One‐Pot Synthesis of Some Novel N‐Methyl Isoxazolidine Derivatives Using N‐Methyl‐α‐chloro Nitrone in Water
Authors: Chakraborty Bhaskar , Sharma Prawin Kumar , Chhetri Manjit Singh
Published: October 2012

A simple one pot and high yield efficient method is described in water for the diastereo and regioselective synthesis of some novel isoxazolidine derivatives at room temperature in a short reaction time.
Chlorotrimethylsilane‐Promoted Condensation of Ketones and Aminoazoles
Authors: Ryabukhin Sergey V. , Naumchik Vasiliy S. , Grygorenko Oleksandr O. , Tolmachev Andrey A.
Published: October 2012

Chlorotrimethylsilane‐promoted reaction of ketones and aminoazoles (i.e., 3‐amino‐1,2,4‐triazoles, 5‐aminotetrazole) at 2 : 1 ratio resulted in the formation of 4,5‐dihydroazolo[1,5‐a]pyrimidine derivatives as the single regioisomers in 35 – 71% yields. In the case of tert‐butylmethylketone and 5‐aminotetrazole as the starting materials, the solvent (dimethylformamide) entered the reaction instead of the second ketone molecule.
2‐Arylimino(diferrocenyl)‐ and (di‐p‐anisyl)dihydropyrimidines: Novel Synthesis, Structures, and Electrochemistry
Authors: Klimova Elena I. , Vázquez López Eduardo A. , Alamo Marcos Flores , Ortiz‐Frade Luis A. , Hernández‐Sánchez Gerardo , Sotelo Domínguez Victor H. , García Marcos Martínez
Published: October 2012

2,3‐Differocenyl‐ and 2,3‐dianisyl‐1‐methylsulfanylcyclopropenilium iodides react with 1,3‐diphenyl‐ and 1,3‐di‐o‐tolylguanidine to give 1‐aryl‐2‐arylimino‐5,6‐ (5a,5b) and ‐4,5‐diferrocenyl‐1,2‐dihydropyrimidines (6a,6b) (∼ 2:1) and, respectively, 5,6‐ and 4,5‐dianisyl‐3‐phenyl‐2‐phenylimino‐1,2‐dihydropyrimidines (∼ 2:1). Their structures were established based on the spectroscopic data and X‐ray diffraction analysis of 5,6‐diferrocenyl‐1‐(o‐tolyl)‐2‐(o‐tolyl)imino‐ and 4,5‐diferrocenyl‐1‐phenyl‐2‐phenylimino‐1,2‐dihydropyrimidines (5b and 6a, respectively). Electrochemical behavior of compounds 5b, 6b, and 5a+6a were investigated using experiments of cyclic voltammetry and chronoamperometry. For all the compounds, two electrochemical processes (I, II), attributed to the oxidations of the ferrocenes moieties were observed. The values of ΔE0′ (II‐I) and comproportionation constant Kcom are also reported. Additionally, an electrochemical oxidation with a fast coupled chemical reaction related to the pyrimide ring was also detected.
Statistical testing of a new testate amoeba‐based transfer function for water‐table depth reconstruction on ombrotrophic peatlands in north‐eastern Canada and Maine, United States
Authors: Amesbury Matthew J. , Mallon Gunnar , Charman Dan J. , Hughes Paul D. M. , Booth Robert K. , Daley Timothy J. , Garneau Michelle
Published: October 2012

Proxy reconstructions of climatic parameters developed using transfer functions are central to the testing of many palaeoclimatic hypotheses on Holocene timescales. However, recent work shows that the mathematical models underpinning many existing transfer functions are susceptible to spatial autocorrelation, clustered training set design and the uneven sampling of environmental gradients. This may result in over‐optimistic performance statistics or, in extreme cases, a lack of predictive power. A new testate amoeba‐based transfer function is presented that fully incorporates the new recommended statistical tests to address these issues. Leave‐one‐out cross‐validation, the most commonly applied method in recent studies to assess model performance, produced over‐optimistic performance statistics for all models tested. However, the preferred model, developed using weighted averaging with tolerance downweighting, retained a predictive capacity equivalent to other published models even when less optimistic performance statistics were chosen. Application of the new statistical tests in the development of transfer functions provides a more thorough assessment of performance and greater confidence in reconstructions based on them. Only when the wider research community have sufficient confidence in transfer function‐based proxy reconstructions will they be commonly used in data comparison and palaeoclimate modelling studies of broader scientific relevance. Copyright © 2012 John Wiley & Sons, Ltd.
Application of monoliths for bioparticle isolation
Authors: Podgornik Aleš , Krajnc Nika Lendero
Published: October 2012

Monoliths are today probably the most studied chromatographic supports. There are plethora of publications dealing with different aspects of their preparation, characterization, and applications. The reason for this interest is their inherent properties related to their particular structure, like ease of preparation in various volumes, fast analytics at low pressure and room temperature, and high productivity as a consequence of flow‐unaffected properties, especially important for isolation of large biological molecules. Because of that, structure of several monoliths was optimized for analytics and purification of biologic nanoparticles like viruses, virus‐like particles (VLPs), cells structures, or even intact cells. In this review, some recent applications of monoliths in the field of bioparticle isolation are described and results are discussed in terms of particular monolith properties.
Development of a fast sample treatment for the analysis of free and bonded sterols in human serum by LC‐MS
Authors: Mendiara Isabel , Domeño Celia , Nerín Cristina
Published: October 2012

The analysis of sterols in biological fluids allows the clinical study of cholesterol related diseases. This research is focused on reducing the sample processing time of the determination of free and bonded sterols in human serum. Ten sterols were studied: cholesterol precursors (desmosterol, lanosterol, and cholestanol); phytosterols (stigmasterol, campesterol, sitosterol, and sitostanol) and oxysterols (7‐α‐hydroxy‐4‐cholesten‐3‐one, 24‐hydroxycholesterol, and 27‐hydroxycholesterol). Ultrasound assistance was used to diminish the reaction time during the alkaline hydrolysis for determining total sterols. Different retention mechanisms of solid‐phase extraction were compared, two reversed‐phase sorbents DSC‐18 and polymeric Oasis‐HLB and a novel zirconia‐coated silica phase. DSC‐18 and zirconia‐coated silica were the most suitable sorbents to analyze these metabolites. The resulting extracts were analyzed by liquid chromatography coupled to mass spectrometry. The analytical parameters were determined and better values were observed with DSC‐18 cartridges for most sterols. LOQ were in the low ng/mL level. Recoveries were in the range 85–99%. Average intermediate precision was 15%. Accuracy for both cartridges was more than 92%. Zirconia‐coated silica showed better performance for the oxysterols, with recoveries around 90%. The procedure allows the determination of free and bonded sterol precursors, phytosterols, and oxysterols in human serum.
Releasing Control: Parents on Vacation
Authors: Ram Yael , Uriely Natan , Malach‐Pines Ayala
Published: October 2012

The paper examines the family vacation phenomenon by comparing parents on vacation (n = 203) with parents during daily life (n = 246) in terms of two psychological constructs: regulatory focus and parenting style. Results revealed that parents in both samples were similar in their ‘regulatory focus of promotion’ (need for challenges) and ‘parenting styles’ (permissive and authoritarian), but parents on vacation scored lower on both need for security (‘regulatory focus of prevention’) and authoritative ‘parenting style’. The findings suggest that parents, especially mothers, view family vacation as an opportunity to relax and release parental control. The findings' theoretical and practical implications are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Temperature Evolution During Processing of Thick‐Walled Anionic Polyamide 6 Composites: Experiment and Simulation
Authors: Teuwen Julie J. E. , van Geenen Ab A. , Bersee Harald E. N.
Published: October 2012

A 1‐D through‐the‐thickness transient heat transfer model is built to simulate the curing process of thick‐walled glass‐fibre‐reinforced anionic polyamide‐6 (APA‐6) composites. The temperature and the degree of polymerisation through the thickness of the composite are calculated and compared to the experimentally obtained results. The kinetic models describing the polymerisation behaviour of APA‐6 are implemented in the model. The kinetic model not taking into account the convection in the polymerisation process shows the best results. It is found that the predicted temperature profiles agree well with the experimental data.

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Living Radical Polymerization and Molecular Imprinting: Improving Polymer Morphology in Imprinted Polymers
Authors: Salian Vishal D. , Byrne Mark E.
Published: October 2012

Living radical polymerization (LRP) techniques and their ability to improve the morphology of crosslinked polymer networks by controlling polymer chain growth are reviewed. Recent successes in the creation of improved molecularly imprinted polymer networks are also discussed. LRP offers the ability to control molecular weight, polydispersity, and tacticity while reducing microgel formation in polymers created via free‐radical polymerization (FRP). The improved network architecture of polymers created via LRP has great potential, especially when considering imprinted networks which have traditionally been plagued by heterogeneity in network morphology and binding affinities. Using LRP can considerably improve template recognition and further delay template transport in imprinted polymers.

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Orientability of the Minor Director of Homeotropically Aligned Smectic‐A Elastomers in External Mechanical Fields
Authors: Brömmel Felicitas , Kramer Dominic , Brown Benjamin P. , Finkelmann Heino , Hoffmann Anke
Published: October 2012

We present studies on bulk smectic‐A copolymer networks with end‐on attached homeotropically oriented mesogens that show spontaneous optical biaxiality at room temperature. Orthoscopic and conoscopic investigations under uniaxial extension in the layer planes give first evidence of the orientability of the minor director in mechanical fields yielding biaxial monodomains with 3‐d orientational long‐range order of all three principle axes. This is an important step towards the synthesis of permanently oriented biaxial monodomain elastomers for which highly interesting mechanical and optical properties are expected.
Kinetic Analysis of A2 + AB2 Polymerization Approach
Authors: Zhou Zhiping , Wang Jingjing , Yan Deyue
Published: October 2012

The kinetic model of the co‐polycondensation with A2 and AB2 type monomers is developed and the analytical expressions of the various molecular parameters of the products are derived rigorously. The monomer feed ratio (α) of A2 to AB2 significantly affects the molecular parameters and the critical condition of gelation. Gelation can be avoided if α is >$1 + \sqrt {3} /2$. At the critical state, the degree of branching decreases firstly and reaches its minimum value at about α≈0.22. Then, it increases with increasing α‐value. In comparison with experimental results, non‐equal reactivity of the active groups should be considered.

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Survival of enterohemorrhagic Escherichia coli in the presence of Acanthamoeba castellanii and its dependence on Pho regulon
Authors: Chekabab Samuel Mohammed , Daigle France , Charette Steve J. , Dozois Charles M. , Harel Josée
Published: October 2012

Enterohemorrhagic Escherichia coli (EHEC) are involved in outbreaks of food‐borne illness and transmitted to humans through bovine products or water contaminated by cattle feces. Microbial interaction is one of the strategies used by pathogenic bacteria to survive in the environment. Among protozoa, the free‐living amoebae are known to host and protect several water‐borne pathogens. In this study, the interaction between EHEC and the predacious protozoa Acanthamoeba castellanii was investigated. Using monoculture and cocultures, growth of both organisms was estimated for 3 weeks by total and viable cell counts. The numbers of EHEC were significantly higher when cultured with amoebae than without, and less EHEC shifted into a viable but nonculturable state in the presence of amoebae. Using several mutants, we observed that the Pho regulon is required for EHEC growth when cocultured with amoebae. In contrast, the Shiga toxins (Stx) were not involved in this association phenotype. Cocultures monitored by electron microscopy revealed a loss of the regular rod shape of EHEC and the secretion of multilamellar vesicles by the amoebae, which did not contain bacteria. As the interaction between A. castellanii and EHEC appears beneficial for bacterial growth, this supports a potential role for protozoa in promoting the persistence of EHEC in the environment.
Theoretical Analysis of Fas Ligand‐Induced Apoptosis with an Ordinary Differential Equation Model
Authors: Shi Zhimin , Li Yan , Liu Zhihai , Mi Jun , Wang Renxiao
Published: October 2012

Upon the treatment of Fas ligand, different types of cells exhibit different apoptotic mechanisms, which are determined by a complex network of biological pathways. In order to derive a quantitative interpretation of the cell sensitivity and apoptosis pathways, we have developed an ordinary differential equation model. Our model is intended to include all of the known major components in apoptosis pathways mediated by Fas receptor. It is composed of 29 equations using a total of 49 rate constants and 13 protein concentrations. All parameters used in our model were derived through nonlinear fitting to experimentally measured concentrations of four selected proteins in Jurkat T‐cells, including caspase‐3, caspase‐8, caspase‐9, and Bid. Our model is able to correctly interpret the role of kinetic parameters and protein concentrations in cell sensitivity to FasL. It reveals the possible reasons for the transition between type‐I and type‐II pathways and also provides some interesting predictions, such as the more decisive role of Fas over Bax in apoptosis pathway and a possible feedback mechanism between type‐I and type‐II pathways. But our model failed in predicting FasL‐induced apoptotic mechanism of NCI‐60 cells from their gene‐expression levels. Limitations in our model are also discussed.
Emulsion Polymerization of Styrene Mediated by TEMPO at Low Temperature
Authors: Montezuma German G. C. , Contant Sheila , Lona Liliane Maria Ferrareso
Published: October 2012

NMRP is a controlled polymerization technique with the ability to produce polymers with a highly controlled microstructure. The properties of the thus obtained polymers make it desirable to scale this technique to an industrial level, but there are still some challenges to be faced, e.g., to develop emulsion NMRP at low temperatures (lower than about 100 °C) with inexpensive, commercially available nitroxides such as TEMPO. Here, the emulsion NMRP of styrene using TEMPO at temperatures lower than 100 °C is described. An optimal control of molecular weights and polydispersities and a fast polymerization rate are obtained.

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Do time restrictions on alcohol advertising reduce youth exposure?
Authors: Ross Craig S. , de Bruijn Avalon , Jernigan David
Published: October 2012

Regulators may attempt to reduce youth exposure to alcohol advertising by restricting times during which alcohol ads may be aired on television or radio. The Netherlands introduced such a policy and found that teenage advertising exposure increased following the time restrictions. This study uses simulation analysis and a comprehensive database of television alcohol advertising to demonstrate that time restrictions are likely to reduce advertising exposure to the youngest viewers while increasing exposure for the high‐risk teenage population. Copyright © 2012 John Wiley & Sons, Ltd.
Rheological and electrical analysis in carbon nanofiber reinforced polypropylene composites
Authors: Paleo Antonio J. , Silva J. , van Hattum F. W. J. , Lanceros‐Méndez Senentxu , Ares A. I.
Published: October 2012

Two different types of carbon nanofibers (CNF) were incorporated in the same polypropylene (PP) matrix by twin‐screw extrusion. The electrical characterization of both CNFs/PP composites as a function of volume fraction show different electrical performance: conducting and nonconducting. The objective of this work is to study the rheological behavior of both composites with the aim of relating it to the electrical behavior. The results indicate that the rheological behaviors are different, suggesting that rheology differentiates the microstructural variations responsible for the electrical performance. Furthermore, the main rheological parameters were correlated to the electrical conductivity. The results show that G′/G″ and G′ are the most sensitive parameters when compared with the onset of electrical percolation. Finally, in spite of the intrinsic measuring differences between electrical and rheological analysis, the two calculated thresholds are very similar: ∼0.5 for the rheological and ∼0.4 for the electrical. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013