bluuebunny/crossref_metadata_2025_split huggingface dataset:
Non‐Invasive High‐Throughput Metrology of Functionalized Graphene Sheets
Authors: Ghazinejad Maziar , Reiber Kyle Jennifer , Guo Shirui , Pleskot Dennis , Bao Duoduo , Vullev Valentine I. , Ozkan Mihrimah , Ozkan Cengiz S. 
Published: July 2012

AbstractThe utilization of fluorescence quenching microscopy (FQM) for quick visualization of chemical functionalization in relatively large regions of graphene, grown via chemical vapor deposition (CVD), is discussed. Through reactive ion plasma etching, patterns of p‐type CVD‐grown graphene functionalized with fluorine are generated. 4‐(dicyanomethylene)‐2‐methyl‐6‐(4‐dimethylaminostyryl)‐4H‐pyran (DCM) is used as the fluorescent agent. The emission of DCM is quenched to a different extent by fluorinated and pristine graphene, which provides the fluorescence‐imaging contrast essential for this metrology. To probe the functionalized surface patterns with DCM, the dye is dispersed in polymethylmethacrylate (PMMA) then the graphene surface is coated, forming a 30‐nm‐thick DCM‐PMMA layer. Fluorescence images of dye‐coated graphene distinctly reveal the difference between the chemically treated and as‐grown regions. The pristine graphene quenches the DCM emission more efficiently than the fluorinated graphene. Therefore, the regions with pristine graphene appear darker on the fluorescence images than the regions with fluorinated graphene, enabling large‐scale mapping of the functionalized regions in CVD grown graphene sheets Due to its simplicity and consistent results, FQM is now poised for widespread adoption by graphene manufacturers as a basis for facile and high throughput metrology of large‐scale graphene sheets.
3D Porous Chitosan–Alginate Scaffolds: A New Matrix for Studying Prostate Cancer Cell–Lymphocyte Interactions In Vitro
Authors: Florczyk Stephen J. , Liu Gang , Kievit Forrest M. , Lewis Allison M. , Wu Jennifer D. , Zhang Miqin 
Published: July 2012

AbstractThe treatment of castration‐resistant prostate cancer (CRPC) remains palliative. Immunotherapy offers a potentially effective therapy for CRPC; however, its advancement into the clinic has been slow, in part because of the lack of representative in vitro tumor models that resemble the in vivo tumor microenvironment for studying interactions of CRPC cells with immune cells and other potential therapeutics. This study evaluates the use of 3D porous chitosan–alginate (CA) scaffolds for culturing human prostate cancer (PCa) cells and studying tumor cell interaction with human peripheral blood lymphocytes (PBLs) ex vivo. CA scaffolds and Matrigel matrix samples support in vitro tumor spheroid formation over 15 d of culture, and CA scaffolds support live‐cell fluorescence imaging with confocal microscopy using stably transfected PCa cells for 55 d. PCa cells grown in Matrigel matrix and CA scaffolds for 15 d are co‐cultured with PBLs for 2 and 6 d in vitro and evaluated with scanning electron microscopy (SEM), immunohistochemistry (IHC), and flow cytometry. Both the Matrigel matrix and CA scaffolds support interaction of PBLs with PCa tumors, with CA scaffolds providing a more robust platform for subsequent analyses. This study demonstrates the use of 3D natural polymer scaffolds as a tissue culture model for supporting long‐term analysis of interaction of prostate cancer tumor cells with immune cells, providing an in vitro platform for rapid immunotherapy development.
Iridium‐Catalyzed Enantioselective Allylic Alkylation of Methyl 2‐(4‐nitrophenylsulfonyl)acetate and Subsequent Transformations
Authors: Xu Qing‐Long , Dai Li‐Xin , You Shu‐Li 
Published: July 2012

AbstractHighly enantioselective allylic alkylation reactions of methyl 2‐(4‐nitrophenylsulfonyl)acetate were carried out in the presence of an iridium catalytic system. The subsequent transformations of the products including reductive desulfonylation and modified Julia olefination led to the allylic alkylation products of methyl acetate or methyl acrylate with good yields and high enantioselectivity.
One‐Pot Tandem Synthesis of 2‐Arylbenzoxazole Derivatives via Copper‐Catalyzed CN and CO Bond Formation
Authors: Kavala Veerababurao , Janreddy Donala , Raihan Mustafa J. , Kuo Chun‐Wei , Ramesh Chintakunta , Yao Ching‐Fa 
Published: July 2012

AbstractThe reaction of 2‐(2‐halophenyl)halobenzamides with a series of nitrogen nucleophiles resulted in the formation of benzoxazole derivatives. This procedure involves copper‐catalyzed one‐pot tandem CN/CO coupling reactions. No ligand was used in the reaction, even in the cases of primary or secondary amides, which were used as N‐nucleophiles. However, L‐proline was used as ligand in the case of N‐aromatic heterocycles like indole, imidazole and pyrazole derivatives.
The Halonium Ion‐Mediated CC Bond Cleavage of Cyclohexene‐Fused Isoxazoline N‐Oxides
Authors: Raihan Mustafa J. , Kavala Veerababurao , Guan Qiao‐Zhi , Kuo Chun‐Wei , Kataria Sunil , Shishodia Shifali , Janreddy Donala , Habib Pateliya Mujjamil , Yao Ching‐Fa 
Published: July 2012

AbstractA protocol for the N‐bromosuccinimide (NBS)‐ and trichloroisocyanuric acid (TCCA)‐mediated cleavage of the CC bond of isoxazoline N‐oxides, fused with a cyclohexene ring, leading to the production of a long‐chain diketo‐halo‐nitrile skeleton is described. The conversion occurs via the formation of a nitric oxide intermediate.
Chondrogenic progenitor cells respond to cartilage injury
Authors: Seol Dongrim , McCabe Daniel J. , Choe Hyeonghun , Zheng Hongjun , Yu Yin , Jang Keewoong , Walter Morgan W. , Lehman Abigail D. , Ding Lei , Buckwalter Joseph A. , Martin James A. 
Published: July 2012

AbstractObjectiveHypocellularity resulting from chondrocyte death in the aftermath of mechanical injury is thought to contribute to posttraumatic osteoarthritis. However, we observed that nonviable areas in cartilage injured by blunt impact were repopulated within 7–14 days by cells that appeared to migrate from the surrounding matrix. The aim of this study was to assess our hypothesis that the migrating cell population included chondrogenic progenitor cells that were drawn to injured cartilage by alarmins.MethodsOsteochondral explants obtained from mature cattle were injured by blunt impact or scratching, resulting in localized chondrocyte death. Injured sites were serially imaged by confocal microscopy, and migrating cells were evaluated for chondrogenic progenitor characteristics. Chemotaxis assays were used to measure the responses to chemokines, injury‐conditioned medium, dead cell debris, and high mobility group box chromosomal protein 1 (HMGB‐1).ResultsMigrating cells were highly clonogenic and multipotent and expressed markers associated with chondrogenic progenitor cells. Compared with chondrocytes, these cells overexpressed genes involved in proliferation and migration and underexpressed cartilage matrix genes. They were more active than chondrocytes in chemotaxis assays and responded to cell lysates, conditioned medium, and HMGB‐1. Glycyrrhizin, a chelator of HMGB‐1 and a blocking antibody to receptor for advanced glycation end products (RAGE), inhibited responses to cell debris and conditioned medium and reduced the numbers of migrating cells on injured explants.ConclusionInjuries that caused chondrocyte death stimulated the emergence and homing of chondrogenic progenitor cells, in part via HMGB‐1 release and RAGE‐mediated chemotaxis. Their repopulation of the matrix could promote the repair of chondral damage that might otherwise contribute to progressive cartilage loss.
Abnormal conformation and impaired degradation of propylthiouracil‐induced neutrophil extracellular traps: Implications of disordered neutrophil extracellular traps in a rat model of myeloperoxidase antineutrophil cytoplasmic antibody–associated vasculitis
Authors: Nakazawa Daigo , Tomaru Utano , Suzuki Akira , Masuda Sakiko , Hasegawa Risa , Kobayashi Toshiaki , Nishio Saori , Kasahara Masanori , Ishizu Akihiro 
Published: July 2012

AbstractObjectiveNeutrophil extracellular traps (NETs) are composed of DNA and antimicrobial proteins, including myeloperoxidase (MPO). Recent studies have demonstrated that impaired regulation of NETs could trigger an autoimmune response. Propylthiouracil (PTU), an antithyroid drug, is associated with a risk of MPO antineutrophil cytoplasmic antibody (ANCA) production and MPO ANCA–associated vasculitis (MPO AAV). This study was undertaken to clarify the mechanism of MPO ANCA production, using the PTU‐induced model of MPO AAV.MethodsNETs were induced by treating human neutrophils with phorbol myristate acetate (PMA) in vitro. We examined whether the addition of PTU influenced the NET formation induced by PMA and the degradation of NETs by DNase I, which is regarded as a regulator of NETs. Furthermore, we examined whether NETs generated by the combination of PMA and PTU induced MPO ANCA and MPO AAV in vivo in rats.ResultsWhen NETs were induced by PMA with PTU using human neutrophils in vitro, abnormal conformation of NETs was observed. Interestingly, the abnormal NETs were hardly digested by DNase I. Moreover, rats immunized with the abnormal NETs, which had been induced by PMA with PTU using rat neutrophils, produced MPO ANCA and developed pulmonary capillaritis. When rats were given oral PTU with intraperitoneal injection of PMA, pauci‐immune glomerulonephritis and pulmonary capillaritis occurred with MPO ANCA production in the serum.ConclusionOur findings indicate that abnormal conformation and impaired degradation of NETs induced by PTU are involved in the pathogenesis of PTU‐induced MPO ANCA production and MPO AAV. These findings suggest that disordered NETs can be critically implicated in the pathogenesis of MPO AAV.
Evidence-based decisions for local and systemic wound care
Authors: Brölmann F E , Ubbink D T , Nelson E A , Munte K , van der Horst C M A M , Vermeulen H 
Published: July 2012

Abstract

Background
Decisions on local and systemic wound treatment vary among surgeons and are frequently based on expert opinion. The aim of this meta-review was to compile best available evidence from systematic reviews in order to formulate conclusions to support evidence-based decisions in clinical practice.

Methods
All Cochrane systematic reviews (CSRs), published by the Cochrane Wounds and Peripheral Vascular Diseases Groups, and that investigated therapeutic and preventive interventions, were searched in the Cochrane Database up to June 2011. Two investigators independently categorized each intervention into five levels of evidence of effect, based on size and homogeneity, and the effect size of the outcomes.

Results
After screening 149 CSRs, 44 relevant reviews were included. These contained 109 evidence-based conclusions: 30 on venous ulcers, 30 on acute wounds, 15 on pressure ulcers, 14 on diabetic ulcers, 12 on arterial ulcers and eight on miscellaneous chronic wounds. Strong conclusions could be drawn regarding the effectiveness of: therapeutic ultrasonography, mattresses, cleansing methods, closure of surgical wounds, honey, antibiotic prophylaxis, compression, lidocaine–prilocaine cream, skin grafting, antiseptics, pentoxifylline, debridement, hyperbaric oxygen therapy, granulocyte colony-stimulating factors, prostanoids and spinal cord stimulation.

Conclusion
For some wound care interventions, robust evidence exists upon which clinical decisions should be based.
19F MRI Monitoring of Gene Expression in Living Cells through Cell‐Surface β‐Lactamase Activity
Authors: Matsushita Hisashi , Mizukami Shin , Mori Yuki , Sugihara Fuminori , Shirakawa Masashiro , Yoshioka Yoshichika , Kikuchi Kazuya 
Published: July 2012

AbstractMagnetic resonance imaging provides important intravital information on deep tissues that cannot be visualized by other methods. Although we had previously developed an off/on switching 19F MRI probe to monitor reporter enzyme activity on the basis of the paramagnetic relaxation enhancement effect, it was difficult to monitor biological events in living cells because the 19F MRI probe did not permeate living cell membrane. In this study, we have developed a new 19F MRI system for monitoring gene expression in living cells by exploiting cell‐surface‐displayed β‐lactamase and the specifically designed 19F MRI probe. By using this system, cellular gene expression was successfully detected by 19F MRI without cell fixation. This imaging strategy shows promise for monitoring in vivo gene expression, and therefore it could lead to useful technologies for the diagnosis and therapy of various diseases.
An improved LQG benchmark for MPC economic performance assessment and optimisation in process industry
Authors: Liu Zhe , Gu Yong , Xie Lei 
Published: July 2012

AbstractPerformance assessment and optimisation for MPC have attracted much research interest. As a typical performance assessment benchmark, the LQG benchmark is regressed from asymmetrical points, leading to unnecessary computation and unsatisfactory regression results. To tackle this problem, an equigrid LQG benchmark was proposed for the two‐layer MPC assessment and optimisation, and the optimal setpoint for MPC was calculated to replace the experiential one. Then the LQG benchmark for sensitivity analysis was introduced. Economic performance assessment of the control system in a delayed coking furnace shows the effectiveness of the proposed approach. © 2012 Canadian Society for Chemical Engineering
Natural gas viscosity estimation using density based models
Authors: Heidaryan Ehsan , Jarrahian Azad 
Published: July 2012

AbstractAccurate value determination of natural gas viscosity plays a key role in its management as it is one of the most important parameters in natural gas engineering calculations. In this study, a comprehensive model is suggested for prediction of natural gas viscosity in a wide range of pressures, temperatures, densities and compositions. The new model can be applicable for gases containing heptane plus and non‐hydrocarbon components. It is validated by the 2011 viscosity data from 18 different gas mixtures. Compared to existing similar models and correlations, its results are quite satisfactory. © 2012 Canadian Society for Chemical Engineering
A measurement‐based study on user management in private BitTorrent communities
Authors: Jiang Honglei , Jin Hai , Guo Song , Liao Xiaofei 
Published: July 2012

SUMMARYBeyond the traditional BitTorrent, a new genre of peer‐to‐peer communications protocol for worldwide file sharing is rapidly evolving towards private BitTorrent (PT). In recent years, a proliferation of PT communities have emerged. To enhance the user experience, account‐based share‐ratio enforcement (SRE) has been developed and widely adopted. Whereas existing studies mainly take SRE as an incentive, we discover that it also plays a critical role in selecting and filtering users. In addition to SRE, a rich set of user management rules, such as registration management, banning policies, and user caste system, are also studied in this paper. This includes to explore their effects on user behavior, download performance, content availability, and system scalability. The measurement results presented in this paper are based on large‐scale experiments conducted over six representative PT sites for over a year. We find that the stricter registration will lead to fewer new users, resulting in a scalability problem, which is critical for the PT communities because the download performance and content availability depend on not only the contribution of users but also the population of the community. Our measurement and analysis pose a direction for the design of new incentive mechanisms that take the difficulty of enrollment into the consideration.Copyright © 2012 John Wiley & Sons, Ltd.
Modified 6‐Aza Uridines: Highly Emissive pH‐Sensitive Fluorescent Nucleosides
Authors: Sinkeldam Renatus W. , Hopkins Patrycja A. , Tor Yitzhak 
Published: July 2012

AbstractOptimized facile syntheses and highly desirable spectroscopic properties of two isomorphic fluorescent pyrimidines, comprising a 1,2,4‐triazine motif conjugated to a thiophene (1 a) or a furan (1 b), are described. Although structurally related to their 5‐modified uridine counterparts, these modified 6‐aza‐uridines reveal dramatically improved fluorescence properties and a remarkable sensitivity to polarity and pH changes. The thiophene derivative 1 a has an absorption maximum around 335 nm, which upon excitation yields visible emission with a polarity‐sensitive maximum and fluorescence quantum yield ranging from 415 nm (Φ=0.8) to 455 nm (Φ=0.2) in dioxane and water, respectively. Nucleoside 1 a also displays susceptibility to acidity. Correlating emission intensity and solution pH yields a pKa value of 6.7–6.9, reasonably close to physiological pH values. The results illustrate that highly sought‐after fluorescence features (brightness and responsiveness) are not necessarily the trait of large fluorophores alone, but can be observed with probes that meet stringent isomorphic design criteria.
Fructose Dehydration to 5‐Hydroxymethylfurfural over Solid Acid Catalysts in a Biphasic System
Authors: Ordomsky Vitaly V. , van der Schaaf John , Schouten Jaap C. , Nijhuis T. Alexander 
Published: July 2012

AbstractDifferent acidic heterogeneous catalysts like alumina, aluminosilicate, zirconium phosphate, niobic acid, ion‐exchange resin Amberlyst‐15, and zeolite MOR have been studied in fructose dehydration to 5‐hydroxymethylfurfural (HMF). The acidity of these materials was characterized using temperature‐programmed desorption of NH3 and IR spectroscopy of adsorbed pyridine. The nature and strength of acid sites was shown to play a crucial role in the selectivity towards HMF. Brønsted acid sites in the case of zeolites and ion‐exchange resin led to high selectivities in the dehydration of fructose with an increase in selectivity with the addition of an organic phase. Lewis acidity in the case of phosphate and oxides resulted in the intensive production of humins from fructose at the initial stages of the process, whereas organic phase addition did not affect selectivity.
Ethanol influences on bax associations with mitochondrial membrane proteins in neonatal rat cerebellum
Authors: Heaton Marieta Barrow , Siler‐Marsiglio Kendra , Paiva Michael , Kotler Alexandra , Rogozinski Jonathan , Kubovec Stacey , Coursen Mary , Madorsky Vladimir 
Published: July 2012

AbstractThese studies investigated interactions taking place at the mitochondrial membrane in neonatal rat cerebellum following ethanol exposure and focused on interactions between proapoptotic Bax and proteins of the permeability transition pore (PTP), voltage‐dependent anion channel (VDAC) and adenine nucleotide translocator (ANT) of the outer and inner mitochondrial membranes, respectively. Cultured cerebellar granule cells were used to assess the role of these interactions in ethanol neurotoxicity. Analyses were made at the age of maximal cerebellar ethanol vulnerability (P4), compared to the later age of relative resistance (P7), to determine whether differential ethanol sensitivity was mirrored by differences in these molecular interactions. We found that, following ethanol exposure, Bax proapoptotic associations with both VDAC and ANT were increased, particularly at the age of greater ethanol sensitivity, and these interactions were sustained at this age for at least 2 h postexposure. Since Bax:VDAC interactions disrupt protective VDAC interactions with mitochondrial hexokinase (HXK), we also assessed VDAC:HXK associations following ethanol treatment and found such interactions were altered by ethanol treatment, but only at 2 h postexposure and only in the P4, ethanol‐sensitive cerebellum. Ethanol neurotoxicity in cultured neuronal preparations was abolished by pharmacological inhibition of both VDAC and ANT interactions with Bax but not by a Bax channel blocker. Therefore, we conclude that, at this age, within the constraints of our experimental model, a primary mode of Bax‐induced initiation of the apoptosis cascade following ethanol insult involves interactions with proteins of the PTP complex and not channel formation independent of PTP constituents. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013
Cell‐Compatible Fluorescent Chemosensor for Zn2+ Based on a 3,8‐Extended 1,10‐Phenanthroline Derivative
Authors: Zhang Bo , Cao Kou‐Sen , Xu Ze‐An , Yang Zhe‐Qin , Chen Hao‐Wen , Huang Wei , Yin Gui , You Xiao‐Zeng 
Published: July 2012

AbstractA new 1,10‐phenanthroline (Phen) derivative, 3,8‐bis(5‐methylthiophen‐2‐yl)‐1,10‐phenanthroline (PHT1), has been synthesized and fully characterized including by single‐crystal X‐ray structure analysis. The electron‐donating effects of the two 5‐methylthiophene groups lead to distinctive fluorescence emission enhancement on complexation with Zn2+ compared with non‐emissive Phen. However, PHT1 shows stronger Zn2+‐sensing ability than 3,8‐bis(thiophen‐2‐yl)‐1,10‐phenanthroline (PHT0) or 3,8‐bis(3‐methylthiophen‐2‐yl)‐1,10‐phenanthroline (PHT2) and longer‐wavelength fluorescence emission (λem = 461 nm), which is vital for studies of living systems, mainly because of the lower steric hindrance and the electron‐donating effects of the 5‐methyl groups on the thiophene rings. More interestingly, PHT1 displays high selectivity towards Zn2+ over a broad range of pH and has an extremely low detection limit (5 ppb). An approximately 51‐fold Zn2+‐selective CHEF response has been attributed to the formation of a 1:2 metal–ligand complex, and the association equilibrium constant (Kass0) of [Zn(PHT1)2](ClO4)2 was determined to be 3.4 × 1012. Anionic effects and variations in the 1H NMR spectra before and after zinc(II) ion complextion were observed. Moreover, the ability of probe PHT1 to sense Zn2+ within living HL‐60, yeast, and HepG‐2 cells has been explored, and the Zn2+‐probing process in living cells was found to be reversible with a zinc chelator solution of N,N,N′,N′‐tetrakis(2‐pyridylmethyl)ethylenediamine (TPEN).
An Insight into the Reversible Dissociation and Chemical Reactivity of a Sterically Encumbered Diphosphane
Authors: Förster Daniela , Dilger Herbert , Ehret Fabian , Nieger Martin , Gudat Dietrich 
Published: July 2012

AbstractThe known 1,1′,3,3′‐tetrahydro‐2,2′‐bi‐1,3,2‐diazaphosphole 4a was for the first time synthesized on a preparative scale and characterized by spectroscopy. Equilibrium constants for the dissociation 4a [rlarr2] 2 5a were determined from quantitative variable‐temperature electron paramagnetic resonance(VT‐EPR) studies and were used to obtain thermochemical data for the P–P bond homolysis. The calculated bond dissociation energy of 79(1) kJ mol–1 is substantially lower than the gas‐phase dissociation energies of small diphosphanes. Modeling of the molecular structure of 4a by DFT calculations was feasible if dispersion effects were included, but the calculations still failed to give a reasonable account of the energetics of the dissociation process. Chemical reactions of 4a with alkynes proceeded, depending on substrate structure, either as a radical‐induced diphosphanation of the triple bond or by a nonradical reaction to give an unprecedented ring metathesis.