bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetically Encoded Bioluminescent Indicator for ERK2 Dimer in Living Cells
Authors: Kaihara Asami , Umezawa Yoshio 
Published: December 2007

AbstractIn this study, a genetically encoded bioluminescent indicator for ERK2 dimer was developed with the split Renilla luciferase complementation method, in which the formation of ERK2 dimer induces a spontaneous emission of bioluminescence in living cells. In response to extracellular stimuli, such as epidermal growth factor (EGF) or 17β‐estradiol (E2), extracellular signal‐regulated kinase 2 (ERK2) is phosphorylated by its upstream kinase MEK, and also phosphorylates its substrates in various regions of the cell, including the nucleus. Phosphorylated ERK2 is led to form its dimer, thereby transporting itself into the nucleus. We demonstrated with the indicator that stimulation with EGF or E2 induces the formation of ERK2 dimer in living MCF‐7 cells. The dynamics of this dimer formation was examined and discussed.
Induction of Optical Activity in an Oligothiophene Synchronized with pH‐Sensitive Folding of Amylose
Authors: Sanji Takanobu , Kato Nobu , Tanaka Masato 
Published: December 2007

AbstractControl of the helical sense in α‐sexithiophene (6T) through pH‐responsive wrapping with left‐handed‐helical amylose is demonstrated. A change in pH of the medium caused a significant conformational change in amylose as the host polymer, which resulted in either supramolecular complexation with 6T as the guest molecule to induce optical activity or decomplexation leading to loss of optical activity. Furthermore, we observed that chirality reversal in 6T does not require hosts of opposite helical chirality, but can be made possible simply by taking advantage of the pH sensitivity of the amylose folding, which is dependent on the pH history of the aqueous medium. In helical amylose, 6T assumes a clockwise‐twisted conformation when the pH is changed from acidic to neutral, but assumes an anticlockwise‐twisted conformation when the aqueous solution is acidified from very basic conditions.
Central venous catheterization—An anatomical review of a clinical skill, Part 2: Internal jugular vein via the supraclavicular approach
Authors: Boon J.M. , Van Schoor A.N. , Abrahams P.H. , Meiring J.H. , Welch T. 
Published: December 2007

AbstractThe safe and successful performance of a central venous catheterization (CVC) requires a specific knowledge of anatomy in addition to a working knowledge. Misunderstanding the anatomy may result in failure or complications. This review aims to aid understanding of the anatomical framework, pitfalls, and complications of CVC of the internal jugular veins. CVC is common practice amongst surgeons, anesthesiologists, and emergency room physicians during the preparations for major surgical procedures such as open‐heart surgery, as well as for intensive care monitoring and rapid restoration of blood volume. Associated with this technique are certain anatomical pitfalls and complications that can be successfully avoided if one possesses a thorough knowledge of the contraindications, regional anatomy, and rationale of the technique. Clin. Anat. 21:15–22, 2008. © 2007 Wiley‐Liss, Inc.
Evaluation of methods to reduce formaldehyde levels of cadavers in the dissection laboratory
Authors: Whitehead Mark C. , Savoia Maria C. 
Published: December 2007

AbstractDissection of conventionally embalmed cadavers exposes students, staff, and faculty to formaldehyde, a probable carcinogen. Therefore, prudent practices should seek to minimize formaldehyde exposure. In this study, we evaluated two commercially available chemicals, InfuTrace and Perfect Solution, for their effectiveness in reducing ambient formaldehyde levels. Four cadavers embalmed conventionally with formaldehyde and/or with the above agents were compared for their formaldehyde levels under conditions that strictly controlled for air circulation and for locations and methods of testing, and during activities that simulated student dissecting. For InfuTrace, one cadaver was reinfused with InfuTrace after initial standard perfusion with formaldehyde; a second cadaver had InfuTrace injected into the thoracic and abdominal body cavities after formaldehyde perfusion. For Perfect Solution, the product was used for embalming a third cadaver in lieu of formaldehyde. For a control, a fourth cadaver was embalmed with the standard formaldehyde solution. Testing of personal and ambient room air samples and of fluid obtained from the cadavers was performed and analyzed in a blinded fashion. Results indicated that both Perfect Solution, substituted for standard formaldehyde embalming, and InfuTrace infused through the vasculature after formaldehyde embalming, resulted in lower concentrations of formaldehyde than embalming with formaldehyde solution alone or in combination with body cavity injection of InfuTrace. These differences in formaldehyde concentrations are consistent across measuring methods, for example, of room air, of breathing zone air during cadaver handling and dissection, and of liquid samples obtained from the cadavers. Perfect Solution yielded suboptimum fixation and a different texture, color, and smell than the formaldehyde treatments. Clin. Anat. 21:75–81, 2008. © 2007 Wiley‐Liss, Inc.
Arterial supply to the sciatic nerve in the gluteal region
Authors: Georgakis Effrossyni , Soames Roger 
Published: December 2007

AbstractThe arterial supply to the sciatic nerve was investigated in 20 human lower limbs (10 right, 10 left) from 20 cadavers (14 females, aged 84 ± 9.6 years, range 66–95 years: 6 males, aged 80 ± 8.2 years, range 70–90 years). In all limbs examined at least 1 sciatic artery could be identified supplying the sciatic nerve in the gluteal region. In total 28 sciatic arteries were identified, of which 14 arose from the medial circumflex femoral artery, 11 from the inferior gluteal artery, 2 from the first perforating artery, and 1 from the internal pudendal artery. In 5 limbs, 2 sciatic arteries were observed, being independent branches from the medial circumflex femoral and inferior gluteal arteries in 4 limbs and separate branches of the medial circumflex femoral artery in 1 limb. In 1 limb, 4 sciatic arteries were observed: 1 from the inferior gluteal artery, 2 from the medial circumflex femoral artery, and 1 from the first perforating artery. In the remaining 14 limbs a single sciatic artery was observed, which in one case arose from the internal pudendal artery, a previously unreported observation. Clin. Anat. 21:62–65, 2008. © 2007 Wiley‐Liss, Inc.
A New Method for Determination of the Adsorption Isotherm of SDS on Polystyrene Latex Particles Using Conductometric Titrations
Authors: Nodehi A. , Moosavian M. A. , Haghighi M. N. , Sadr A. 
Published: December 2007

AbstractMonodisperse polystyrene (PS) latex particles were prepared through a conventional batch emulsion polymerization procedure. After cleaning, the latex was subjected to a surfactant titration by sodium dodecyl sulfate (SDS) and the conductivity was monitored. Using the break point in the conductivity‐concentration curve, the adsorption area of the surfactant molecules at saturation, As, was determined as 46 Å2 per SDS molecule. In order to determine the contribution of the different ionic species to the conductivity, a simple model based on experimental conductivity measurements was developed. The degrees of counterion binding to the micelles and to the surfactant anions adsorbed onto polymer particles were calculated as 0.770 and 0.849, respectively. The Langmuir adsorption isotherm was determined for the adsorption of SDS onto PS latex particles with Γ∞ = 7.257 · 10–10 mol/cm2 and K = 1.208 · 105 cm3/mol.
Oxidation of Benzene to Maleic Anhydride in a Fluidized Bed Reactor
Authors: Uraz C. , Atalay S. 
Published: December 2007

AbstractIn this project, the selective oxidation of benzene to maleic anhydride (MAN) was studied. Gas phase catalytic oxidation of benzene was carried out in a laboratory scale fluidized bed reactor on six different types of catalysts, which have different compositions. Effects of temperature, flow rates of benzene and air and catalyst type on the reaction selectivity were investigated at atmospheric pressure. The experiments were performed over a temperature range of 325 to 400 °C, a space‐time (W/FA0) range from 11.28 × 105 to 31.9 × 105 g s mol–1, and benzene/air mole ratio changes between 0.0109 and 0.0477. It was seen that conversion of benzene to MAN increased with increasing temperature for the catalysts supported by silica gel, aluminum oxide and titanium oxide. From the results it was found that conversion increased with increasing flow rate of air. When the comparison of the catalysts were made, it could be said that catalysts supported by silica gel showed higher MAN conversions. So it can be concluded that catalysts supported by silica gel were more suitable catalysts for benzene oxidation to MAN in a fluidized bed reactor.
Simulation of Barium Sulfate Precipitation using CFD and FM‐PDF Modeling in a Continuous Stirred Tank
Authors: Wang Z. , Zhang Q. H. , Yang C. , Mao Z.‐S. , Shen X. Q. 
Published: December 2007

AbstractA mixing‐precipitation model combining computational fluid dynamics (CFD), finite‐mode PDF (probability density function) model, population balance and kinetic modeling has been proposed to simulate the barium sulfate precipitation process in a continuous stirred tank agitated by a Rushton turbine. The effect of various operating conditions such as impeller speed, feed concentration, feed position and mean residence time on the barium sulfate precipitation process is clearly demonstrated. It is shown that the mean crystal size increases by increasing the impeller speed and mean residence time. However, when the feed concentration is increased, the mean crystal size decreases. The predictions are in reasonable agreement with the experimental data in the literature.
Determining Cyclone Particle Holdup by Pressure Drop for a CFB Boiler
Authors: Li S. H. , Zhang H. , Yang H. R. , Yang S. , Lu J. F. , Yue G. X. 
Published: December 2007

AbstractAn experimental study was conducted to assess the possibility of determining particle holdup by measuring the pressure drop of a conventional cyclone used in a circulating fluidized bed (CFB) boiler. It was found that within a wide range of inlet solid concentrations, i.e., 0.54–4.42 kg/kg‐gas, the cyclone pressure drop increased linearly with inlet solid concentration at a given gas velocity, while the pressure drop between the dust exit and the vortex finder of the cyclone remained almost constant. Since particle holdup increases virtually linearly with solid flow rate, the particle holdup in the cyclone can be derived from the cyclone pressure drop, and therefore, an equation set was proposed to calculate the particle holdup from the cyclone pressure drop.
Reaction Kinetics of Soybean Oil Transesterification Using Heterogeneous Metal Oxide Catalysts
Authors: Singh A. K. , Fernando S. D. 
Published: December 2007

AbstractHomogeneous acid or base catalysts dissolve fully in the glycerol layer and partially in the fatty acid methyl ester (biodiesel) layer in the triglyceride transesterification process. Heterogeneous (solid) catalysts, on the other hand, can prevent catalyst contamination making product separation much simpler. In the present work, the transesterification kinetics of five different solid catalysts with soybean oil is presented. It is found that heterogeneous catalysts require much higher temperatures and pressures to achieve acceptable conversion levels compared to homogeneous catalysts. Subsequent to preliminary investigations, transesterifications were conducted for selected high performance solid catalysts, i.e., MgO, CaO, BaO, PbO, and MnO2 in a high pressure reactor up to a temperature of 215 °C. The yield of the fatty acid methyl esters and the kinetics (rate constant and order) of the reaction are estimated and are compared for each catalyst.
Radial Gas Mixing in a Fluidized Bed with a Multi‐Horizontal Nozzle Distributor using Response Surface Methodology
Authors: Chyang C.‐S. , Qian F.‐P. , Chiou H.‐Y. 
Published: December 2007

AbstractThe gas mixing in the radial direction within a fluidized bed equipped with a multi‐horizontal nozzle distributor was studied using response surface methodology (RSM), which enables the examination of parameters with a moderate number of experiments. All experiments were carried out in a circular fluidized bed of 0.29 m I.D. cold model fluidized bed. The distributor is placed beside twenty‐two horizontal nozzles that are arranged in three concentric circles with all existing discharge directed clockwise. The tracer gas (CO2) was discharged into the bed as a tracer gas and the analysis was performed with a gas chromatograph. In order to compare the different internal circulations, the tracer gas was discharged in the center area or annular area of the bed. In RSM, the static bed height, superficial velocity and the open area ratio of the distributor are chosen as the research variables, and the standard deviation of the time averaged radial tracer concentration is used as the objection function. A mathematical model for the gas mixing as a function of the operating parameters was empirically proposed. The results show that the standard deviation of time averaged radial tracer concentration is well correlated with the operating and geometry parameters, (U – Umf)/Umf, Hs/D and ψd, and that the tracer gas injected to the center position has a better dispersion than when injected to the annular position. This model can be used for optimizing the design of fluidized bed reactors at a required performance level.
Simulation and Analysis of a Single‐Effect Thermal Vapor‐Compression Desalination System at Variable Operation Conditions
Authors: Ji J. G. , Wang R. Z. , Li L. X. , Ni H. 
Published: December 2007

AbstractA mathematical model is developed to analyze a single‐effect thermal vapor compression (TVC) desalination system. The effects of the variation of operation conditions such as the intake seawater temperature and the mass flow rate of cooling water on the system performance are investigated for a specific desalination unit. The system performance is found to decrease when the intake seawater temperature is different from the design value. By adjusting the mass flow rate of cooling water, a better system performance can be obtained when the intake seawater temperature differs from the design conditions. Decreasing the cooling water flow rate to values lower than the design value can lead to a better performance when the intake seawater temperature is lower than the design value, and the system performance reaches a peak point when the cooling water flow rate decreases to a definite level. A better performance can also be obtained by increasing the cooling water flow rate to values higher than design value, when the intake seawater temperature is higher than the design value and the system performance also reaches a peak point when the cooling water flow rate increases to a definite level.
A Digital Imaging Technique for the Analysis of Local Inhomogeneities from Agitated Vessels
Authors: Visuri O. , Laakkonen M. , Aittamaa J. 
Published: December 2007

AbstractA novel, cheap and simple technique for the analysis of the mixing properties from a stirred vessel is introduced. The technique is based on a digital imaging technique and the analysis can be undertaken based on the properties of the image. Using this technique, it is easy to analyze mixing inhomogeneities. Test measurements with non‐Newtonian viscous, aqueous xanthan solutions and fluids as well as liquid‐particle suspensions showed that the developed method is a quick and quantitative tool for the analysis of local mixing inhomogeneities, mixing times and particle suspension speeds.
Microstructured Reactors in Heterogenous Catalysis
Authors: Klemm E. , Döring H. , Geisselmann A. , Schirrmeister S. 
Published: December 2007

AbstractA number of heterogeneously catalyzed reactions, mainly gas‐phase reactions, have been performed previously at a laboratory scale and a successful proof of concept was achieved. Since the beginning of this century, there has been a shift in focus on the transfer from laboratory scale to production scale. In particular, this review deals with the technical concepts and economic aspects involved in such a shift. Heterogenously catalyzed gas‐phase and liquid‐phase processes are discussed separately. The preparation of wall catalysts is a key technology in both cases and is described in an additional subsection. Finally, an evaluation of the developmental status is given.
Determination of Mixing Times with Helical Ribbon Impeller for Non‐Newtonian Viscous Fluids Using an Advanced Imaging Method
Authors: Chhabra R. P. , Bouvier L. , Delaplace G. , Cuvelier G. , Domenek S. , André C. 
Published: December 2007

AbstractNew results on mixing times for viscous Newtonian and non‐Newtonian fluids being homogenized with a helical ribbon impeller are presented. In particular, a recently developed technique to determine the macromixing kinetics of an impeller in a transparent vessel was applied to investigate the effects of rheological properties on mixing times. Significant differences were observed in the mixing times for viscous Newtonian and non‐Newtonian fluids. Based on the new data obtained in this work, a correlation incorporating the elastic effects is proposed in terms of a Weissenberg number for predicting the mixing time as a function of the Reynolds number and the system geometry.
Multiperiod Investment Models for the Gradual Reconstruction of Chemical Processes
Authors: Novak‐Pintaric Z. , Kravanja Z. 
Published: December 2007

AbstractA multiperiod mixed‐integer nonlinear programming (MINLP) model is presented for the planning of an optimal investment policy for the gradual retrofit of chemical plants over a specified time frame. This approach can be applied when the available funds are insufficient to perform the optimal reconstruction in one step. Through gradual improvements, the process progressively approaches its optimum with considerably lower requirements for new capital, while still exhibiting an attractive increase in economic performance. In the proposed multiperiod problem for gradual retrofit, certain amounts of capital enter into the time periods for the gradual increase of equipment in order to improve the performance of the process, e.g., to lead to an increase in conversion or energy recovery. This capital may arise from internal sources within the company or can be borrowed. The financial benefits resulting from the improvements at the end of the time period can be reinvested for the additional reconstruction over the next development phases. In this way, self‐sustained capital generation for future reconstruction is achieved, and any additional funds required are minimized. The objective function of the proposed problem is formulated as the net present worth of the gradually retrofitted system. This enables several techno‐economic analyses to be performed. The proposed multiperiod investment strategies are illustrated by an investment planning example for the retrofit of a heat‐exchanger network.
Precursor Approach to Lanthanide Dioxo Monocarbodiimides Ln2O2CN2 (Ln=Y, Ho, Er, Yb) by Insertion of CO2 into Organometallic Ln–N Compounds
Authors: Zeuner Martin , Pagano Sandro , Schnick Wolfgang 
Published: December 2007

AbstractWe present two organometallic precursor approaches leading to the hitherto‐unknown dioxo monocarbodiimides (Ln2O2CN2) of the late lanthanides Ho, Er, and Yb as well as yttrium. One involves insertion of CO2, and the other one is a straightforward route using a molecular single‐source precursor. To this end the reactivity of the activated amido lanthanide compound [(Cp2ErNH2)2] towards carbon dioxide absorption under supercritical conditions was studied. Selective insertion of CO2 into the amido complex yielded the single‐source precursor [Er2(O2CN2H4)Cp4], which was characterized by vibrational spectroscopy and thermal and elemental analyses. Ammonolysis of this amorphous compound at 700 °C affords Er2O2CN2. To gain deeper insight into the structural characteristics of the amorphous precursor, a similar molecular carbamato complex was synthesized and fully characterized. X‐ray structure analysis of the dimeric complex [Cp4Ho2{μ‐η1:η2‐OC(OtBu)NH}] shows an unusual bonding mode of the tert‐butylcarbamate ligand, which acts as both a bridging and side‐on chelating group. Ammonolysis of this compound also yielded dioxo monocarbodiimides, and therefore the crystalline carbamato complex turned out to be an alternative precursor for the straightforward synthesis of Ln2O2CN2. Analogously, the dioxo monocarbodiimides of Y, Ho, Er, and Yb were synthesized by this route. The crystal structures were determined from X‐ray powder diffraction data and refined by the Rietveld method (Ln=Ho, Er). Further spectroscopic characterization and elemental analysis evidenced the existence of phase‐pure products. The dioxo monocarbodiimides of holmium and erbium crystallize in the trigonal space group P$\bar 3$m1. According to X‐ray powder diffraction, they adopt the Ln2O2CN2 (Ln=Ce–Gd) structure type.
Zn[BPO4(OH)2]: A Zinc Borophosphate with the Rare Moganite‐Type Topology
Authors: Huang Ya‐Xi , Prots Yurii , Kniep Rüdiger 
Published: December 2007

AbstractA novel zinc borophosphate Zn[BPO4(OH)2] with moganite‐type topology (a rare polymorph of silica) has been prepared from a mixture of ZnO, B2O3, and P2O5 by hydrothermal treatment at 443 K. The crystal structure was determined from single‐crystal X‐ray data (orthorhombic, Pbcn (no. 60), a=915.07(3), b=897.22(3), c=1059.19(3) pm, V=869.62(5)×106 pm3, Z=8, R1=0.028, wR2=0.075). The crystal structure comprises unbranched vierer‐single borophosphate chains running along [010] and interconnected via ZnO2(OH)2‐tetrahedra by sharing common vertices. The resulting topology of the three‐dimensional tetrahedral framework structure is described by the Schläfli symbol (42.62.82)(4.64.8)2. Although showing Zn in a tetrahedral coordination, the title compound does not belong to the group of zincoborophosphates but is a special case of a borophosphate containing vierer single rings of tetrahedra with the sequence Zn‐B‐Zn‐P.
The Local Crystal Chemistry and Dielectric Properties of the Cubic Pyrochlore Phase in the Bi2O3—M2+O—Nb2O5 (M2+: Ni2+ and Mg2+) Systems.
Authors: Nguyen Binh , Liu Yun , Withers Ray L. 
Published: December 2007

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