bluuebunny/crossref_metadata_2025_split huggingface dataset:
A functional polysiloxane with benzophenone derivative ultraviolet absorbing side groups: Synthesis, morphology, and its performance on fabrics
Authors: An Qiufeng , Li Linsheng , Lu Dedai , Huang Liangxian 
Published: January 2007

AbstractA novel functional polysiloxane (PSBP) bearing benzophenone derivatives as UV absorbing side groups was synthesized by hydrosilylation of polyhydromethylsiloxane (PHMS) with 2‐hydroxy‐4‐(β‐hydroxy‐γ‐allyloxy)propyloxy benzophenone (HHAPB). The chemical structure, film morphology, and the softening fabric property of the synthesized polysiloxane were characterized and investigated by spectrum analysis, atomic force microscope (AFM), and Kawabata evaluation system. The experiment results indicated that PSBP was not only an excellent polymeric UV‐absorber, which showed intensive ultraviolet absorptions respectively, at wavelengths of 243.2, 288.2, and 325.4 nm, but could exhibit a nonhomogeneous, some rough structure film on silicon wafer substrate. In addition, the functional side group, benzophenone derivative as well as its mass ratio to PSBP has an influence on the performance of the synthesized polysiloxane. As the mass ratio decreased from 31.48 to 12.87%, the molar extinction coefficients εmax (λmax = 288.2 nm) of the PSBP fluids lowered from 3.4564 × 105 to 1.5763 × 105, but while the softening fabric properties of PSBP on cotton fabrics increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 680–687, 2007
Orbital period variation of the eclipsing binary system TT Herculis
Authors: Selam S. O. , Albayrak B. 
Published: February 2007

AbstractNew photoelectric UBV observations were obtained for the eclipsing binary TT Her at the Ankara University Observatory (AUO) and three new times of minima were calculated from these observations. The (O – C) diagram constructed for all available times of minima of TT Her exhibits a cyclic character superimposed on a quadratic variation. The quadratic character yields an orbital period decrease with a rate of dP /dt = –8.83 × 10–8 day yr–1 which can be attributed to the mass exchange/loss mechanism in the system. By assuming the presence of a gravitationally bound third body in the system, the analysis of the cyclic nature in the (O – C) diagram revealed a third body with a mass of 0.21M⊙ orbiting around the eclipsing pair. The possibility of magnetic activity cycle effect as a cause for the observed cyclic variation in the (O – C) diagram was also discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Poly(D,L‐lactide‐co‐glycolide acid) nanoparticles for DNA delivery: Waiving preparation complexity and increasing efficiency
Authors: Koby Gvili , Ofra Benny , Dganit Danino , Marcelle Machluf 
Published: February 2007

AbstractWhen designing a nonviral gene delivery system based on polymeric nanoparticles (NPs), it is important to keep in mind obstacles associated with future clinical applications. Simplifying the procedure of NPs production and taking toxicity into account are the most important issues that need to be addressed. Toxicity concerns in clinical trials may be raised when using additives such as cationic polymers/lipids, buffering reagents, and proteins. Therefore, the aim of this study was to simplify the formulation of poly (lactide‐co‐glycolide) acid NPs by shortening steps such as sonication time and by avoiding the use of additives while preserving its efficiency. NPs (300 nm) were formulated using a modified w/o/w technique with DNA entrapment efficiency of 80%. Once achieving such NPs, formulation parameters such as DNA loading, release kinetics, DNA integrity and bioactivity, uptake by cells, and toxicity were addressed. The NPs were readily taken by several cell lines and were localized mostly in their endo‐lysosomal compartments. The NPs did not affect cells viability. Most importantly, transfection studies in COS‐7 and Cf2th cells resulted with a 250‐fold protein expression levels when compared with the control. These expression levels are higher than ones achieved with more complicated NPs systems, demonstrating the efficiency of our simplified NPs for gene delivery. © 2007 Wiley Periodicals, Inc. Biopolymers 85: 379–391, 2007.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Butanol production from agricultural residues: Impact of degradation products on Clostridium beijerinckii growth and butanol fermentation
Authors: Ezeji Thaddeus , Qureshi Nasib , Blaschek Hans P. 
Published: February 2007

AbstractDuring pretreatment and hydrolysis of fiber‐rich agricultural biomass, compounds such as salts, furfural, hydroxymethyl furfural (HMF), acetic, ferulic, glucuronic, ρ‐coumaric acids, and phenolic compounds are produced. Clostridium beijerinckii BA101 can utilize the individual sugars present in lignocellulosic [e.g., corn fiber, distillers dry grain solubles (DDGS), etc] hydrolysates such as cellobiose, glucose, mannose, arabinose, and xylose. In these studies we investigated the effect of some of the lignocellulosic hydrolysate inhibitors associated with C. beijerinckii BA101 growth and acetone–butanol–ethanol (ABE) production. When 0.3 g/L ρ‐coumaric and ferulic acids were introduced into the fermentation medium, growth and ABE production by C. beijerinckii BA101 decreased significantly. Furfural and HMF are not inhibitory to C. beijerinckii BA101; rather they have stimulatory effect on the growth of the microorganism and ABE production. Biotechnol. Bioeng. 2007;97:1460–1469. © 2007 Wiley Periodicals, Inc.
Photochemical Production of Vitamin D2, Scale‐up and Optimization
Authors: Jike L. , Bei S. Y. , Yun M. J. , Li D. , Fang W. , Wei T. T. 
Published: January 2007

AbstractAn effective low cost method for the photochemical production of vitamin D2 has been studied, including a 200 L batch photoreactor and a continuous reactor. Following optimization of the irradiation time (550 min), initial concentration of ergosterol (1.4 mg/mL) and the number of lamps employed (16) for the batch reactor, the conversion of ergosterol is ca. 50 %, and the selectivity yield of pre‐vitamin D2 is ca. 84 %. The corresponding data for the continuous reactor are 73 % and 62 %, respectively.
Aufbereitung organischer Extraktphasen mittels Ultrafiltration bei der Schwermetallextraktion
Authors: Reinhart R. , Haseneder R. , Härtel G. 
Published: January 2007

AbstractEin Membranverfahren wie die Ultrafiltration ist prinzipiell zur Trennung von beladenem und unbeladenem Extraktionsmittel geeignet. Ferner besteht die Möglichkeit, durch die Kombination aus Laserscanner‐Messstand und Hochdruckmikrowaage Aussagen bezüglich Sorption und Quellung von Ultrafiltrationsmembranen sowohl anhand von gravimetrischen als auch optischen Messungen zu treffen. Aus den Ergebnissen der Permeationsversuche der eingesetzten Modellsubstanzen wird ersichtlich, dass sich das Aufkonzentrierungsverfahren mit Hilfe von Membranen aus regenerierter Cellulose sowohl für zwei‐ als auch dreiwertige Metallsalze eignet.
Modifizierung superabsorbierender Polymere mit hochkomprimiertem CO2
Authors: Schulz B. , Cleve E. , Krekel G. , Knopf K. , Cinquemani C. 
Published: January 2007

AbstractSuperabsorbierende Polymere, die man u. a. in Hygieneprodukten einsetzt, werden aus dem flüssigem und überkritischem CO2‐Zustand von 275 bar durch eine schnelle Expansion gebläht. Dadurch erzielte deutliche Veränderungen in der Oberflächenstruktur können durch rasterelektronenmikroskopische Aufnahmen (REM) erkannt werden. Messtechnisch lassen sich erhebliche Verbesserungen des Quellungsgrades und der Kinetik der Flüssigkeitsaufnahme bestimmen.
Entwicklung eines Thermogravimetrie‐Reaktors zur reaktionstechnischen Untersuchung heterogen katalysierter Reaktionen
Authors: Krautwald J. , Schnitzlein K. 
Published: January 2007

AbstractAls Ersatz für den Standardtiegel in konventionellen Thermowaagen wird ein zwangsdurchströmter Thermogravimetrie‐Reaktor entwickelt, der kinetische Untersuchungen bei eindeutigen Strömungsverhältnissen erlaubt. Hierfür wird eine Kombination von numerischer Strömungssimulation und Experiment verwendet. Der Nachweis der Zwangsdurchströmung erfolgt mittels einer modifizierten Naphthalin‐Sublimationstechnik.
Optische Inline‐Messverfahren zur Zellzahl‐ und Zellgrößenbestimmung in der Bioprozesstechnik
Authors: Rudolph G. , Brückerhoff T. , Bluma A. , Korb G. , Scheper T. 
Published: January 2007

AbstractZur Beobachtung und Regelung von Kultivierungsprozessen werden zunehmend optische Sensoren verwendet. Wichtige Parameter für eine Kontrolle von Kultivierungsprozessen sind die Zellzahl, die Zellmorphologie und die Zellgrößenverteilung. Neben Trübungsmessverfahren werden auch bildgebende Verfahren für die Bestimmung dieser Prozessparameter eingesetzt. Ein Nachteil der meisten bisher entwickelten bildgebenden Verfahren ist, dass sie nur offline zur Verfügung stehen und somit Probenahmen erforderlich sind. Verfügbare bildgebende Inline‐Sonden können dagegen bis heute nur eine begrenzte Anzahl an Kultivierungsparametern bestimmen. In diesem Beitrag werden neue optische Verfahren vorgestellt, die für die Inline‐Bestimmung der Zellzahl, Zellgrößenverteilung und weiterer Parameter eingesetzt werden können. Speziell am Beispiel der In‐situ‐Mikroskopie wird ein bildgebendes Verfahren beschrieben, dass die Bestimmung direkter und indirekter Zellparameter in Echtzeit und ohne Probenahme erlaubt.
Berechnung des Druckverlustes in glatten konzentrischen Ringspalten bei ausgebildeter laminarer und turbulenter isothermer Strömung
Authors: Gnielinski V. 
Published: January 2007

AbstractDoppelrohrapparate, die aus zwei ineinander gesteckten Rohren bestehen, werden als einfache Konstruktion u. a. in der Reaktionstechnik zur Wärmeübertragung verwendet. Die im Ringraum auftretende Reibung zwischen dem strömenden Medium und den Wänden führt zu einem Druckverlust des Strömungsmediums. Über den Reibungsbeiwert, der zur Berechnung des Druckverlusts benötigt wird, ist in den einschlägigen Handbüchern wenig zu finden.
Two‐Focus Fluorescence Correlation Spectroscopy: A New Tool for Accurate and Absolute Diffusion Measurements
Authors: Dertinger Thomas , Pacheco Victor , von der Hocht Iris , Hartmann Rudolf , Gregor Ingo , Enderlein Jörg 
Published: February 2007

AbstractWe present a new method to measure absolute diffusion coefficients at nanomolar concentrations with high precision. Based on a modified fluorescence correlation spectroscopy (FCS)‐setup, this method is improved by introducing an external ruler for measuring the diffusion time by generating two laterally shifted and overlapping laser foci at a fixed and known distance. Data fitting is facilitated by a new two‐parameter model to describe the molecule detection function (MDF). We present a recorded MDF and show the excellent agreement with the fitting model. We measure the diffusion coefficient of the red fluorescent dye Atto655 under various conditions and compare these values with a value achieved by gradient pulsed field NMR (GPF NMR). From these measurements we conclude, that the new measurement scheme is robust against optical and photophysical artefacts which are inherent to standard FCS. With two‐focus‐FCS, the diffusion coefficient of 4.26×10−6cm2 s−1for Atto655 in water at 25 °C compares well with the GPF NMR value of 4.28×10−6cm2 s−1.
Pulsed Electrical Discharge in Bubbled Water
Authors: Gershman S. , Mozgina O. , Belkind A. , Becker K. , Kunhardt E. 
Published: February 2007

AbstractElectrical discharges in water are used for generating hydrogen peroxide, ozone, hydroxyl and oxygen radicals, and other chemically active species for disinfection and purification of water. The interest in electrical discharges in bubbled water is motivated by the need to reduce the power consumption for igniting the discharge. Understanding the electrical and optical characteristics of the discharge will help guide the design of future purification systems. Here we report results of investigations that focus on the study of pulsed electrical discharges in a single bubble of oxygen or argon in water. The single‐bubble system consists of a negative needle electrode inside a gas bubble in water and a disk electrode separated from the needle electrode by 5 –10 mm of water. The bubble is stationary and is subjected to repeated 3 – 15 kV, 1 μs long voltage pulses. At these voltage levels, the discharge process is confined to the bubble with the water serving as a dielectric material covering the disk electrode. During a single voltage pulse multiple ∼100 ns long discharges occur in the bubble. These discharges deposit sufficient amount of charge on the surface of the bubble to generate a reverse‐polarity discharge during the voltage shut‐off. Experiments with Ar and O2 bubbles show the same optical emission intensity at 309 ± 5 nm (OH emissions). These results indicate that OH radicals are generated by electron‐driven processes in water vapor present in all bubbles. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A single platform image cytometer for resource‐poor settings to monitor disease progression in HIV infection
Authors: Ymeti Aurel , Li Xiao , Lunter Björn , Breukers Christian , Tibbe Arjan G. J. , Terstappen Leon W. M. M. , Greve Jan 
Published: January 2007

AbstractBackgroundFor resource‐poor countries, affordable methods are required for enumeration of CD4+ T lymphocytes of HIV‐positive patients. For infants, additional determination of CD4/CD8 ratio is needed.MethodsWe determine the CD4+ and CD8+ T lymphocytes as the CD3+CD4+ and CD3+CD8+ population of blood cells. Target cells are CD3‐immunomagnetically separated from the whole blood, and CD4‐Phycoerythrin and CD8‐PerCP immunofluorescently labeled. A point‐of‐care single platform image cytometer was developed to enumerate the target CD3+CD4+ and CD3+CD8+ populations. It has light‐emitting diodes illumination, is fully computer‐controlled, operates from a 12 V battery, and was designed to be cheap and easy‐to‐handle. Target cells are imaged on a CCD camera and enumerated by an image analysis algorithm. The cytometer outputs the absolute number of CD4+ and CD8+ T lymphocytes/μl and CD4/CD8 ratio.ResultsThe quality of the cell images obtained with the cytometer is sufficient for a reliable enumeration of target cells. The image cytometer achieves an accuracy of better than 10% in the range of 50–1700 cells/μl. Analysis of blood samples from HIV patients yields a good agreement with the TruCount method for CD4 and CD8 count and CD4/CD8 ratio.ConclusionsThe image cytometer is affordable (component costs $3,000), compact (25 × 25 × 20 cm3), and uses disposable test materials, making it a good candidate to monitor progression of immunodeficiency disease in resource‐poor settings. © 2007 International Society for Analytical Cytology.
Expression of inhibitory receptor ILT3 on neoplastic B cells is associated with lymphoid tissue involvement in chronic lymphocytic leukemia
Authors: Colovai Adriana I. , Tsao Lawrence , Wang Su , Lin Hana , Wang Chuan , Seki Tetsunori , Fisher Julie G. , Menes Manuel , Bhagat Govind , Alobeid Bachir , Suciu‐Foca Nicole 
Published: February 2007

AbstractT cell responses against leukemia‐associated antigens have been reported in chronic lymphocytic leukemia (CLL). However, the relentless accumulation of CLL B cells in some patients indicates that anti‐tumor immune responses are inefficient. Inhibitory receptors from the Ig‐like transcript (ILT) family, such as ILT3 and ILT4, are crucial to the tolerogenic activity of antigen presenting cells. In this study, we examined the expression of ILT3 on CD5+ B cells obtained from 47 patients with CLL. Using flow cytometry and RT‐PCR, we found that B CLL cells from 23 of 47 patients expressed ILT3 protein and mature ILT3 mRNA. ILT3 protein and mRNA were not found in normal B cells obtained from donors without CLL. Expression of ILT4 in normal and B CLL cells showed a pattern similar to ILT3. The frequency of ILT3 positive CLL B cells was higher in patients with lymphoid tissue involvement, suggesting that ILT3 may have prognostic value in CLL. Our findings indicate that expression of ILT3 and ILT4 on CLL B cells represents a phenotypic abnormality that may play a role in tolerization of tumor‐specific T cells. © 2007 Clinical Cytometry Society
Effects of high‐dose vitamin E supplementation on oxidative stress and microalbuminuria in young adult patients with childhood onset type 1 diabetes mellitus
Authors: Giannini C. , Lombardo F. , Currò F. , Pomilio M. , Bucciarelli T. , Chiarelli F. , Mohn A. 
Published: February 2007

AbstractIntroductionThe aim of this study was to evaluate the effects of high‐dose vitamin E supplementation (1200 mg/day) on reducing both microalbuminuria (MA) and oxidative stress in patients with type 1 diabetes mellitus (T1DM) and persistent MA.MethodsWe performed a 12‐month, randomized, placebo‐controlled, double‐blind cross‐over trial in ten Caucasian young adults (7m/3f; mean age 18.87 ± 2.91 years) with T1DM and persistent MA.At baseline and at end of the treatment period, determination of albumin excretion rate (AER) and HbA1c and evaluation of the oxidant/antioxidant status were performed.ResultsAt the beginning of the study, AER and HbA1c were not significantly different between the vitamin E and placebo group. No differences in terms of oxidant and antioxidant status were found between the two groups. This was associated with no significantly different urinary VEGF and TGF‐β levels. After 6 months, no significant differences in AER were observed between the two groups (p = 0.59). However, plasma and LDL‐vitamin E content were significantly higher in the vitamin E group compared to the placebo group (p = 0.0001 and p = 0.004, respectively). This was associated with a significantly longer lag phase (p = 0.002) and lower MDA (p = 0.049). However, no statistically significant differences were detected in terms of VEGF and TGF‐β urinary levels.ConclusionThese data demonstrate that high‐dose vitamin E supplementation reduces markers of oxidative stress and improves antioxidant defence in young patients with T1DM. However, although it positively affects the oxidant/antioxidant status, vitamin E supplementation does not reduce AER in patients with T1DM and persistent MA. Copyright © 2007 John Wiley & Sons, Ltd.
Ubiquitous and uniform in vivo fluorescence in ROSA26‐EGFP BAC transgenic mice
Authors: Giel‐Moloney Maryann , Krause Daniela S. , Chen Gang , Van Etten Richard A. , Leiter Andrew B. 
Published: February 2007

AbstractTransplantation studies and cell lineage analyses require the ability to explicitly distinguish morphologically identical cells that have an identifiable marker indicating their origin in vivo. Several reporter mouse strains have been generated for such studies, but pancellular detection of the marker in all tissues has not been achieved. In this report, we describe the generation of transgenic mice that express enhanced green fluorescent protein (EGFP) under control of a 187 kb bacterial artificial chromosome (BAC) containing the murine ROSA26 locus, and show several advantages over existing EGFP reporter lines. It is demonstrated that EGFP is ubiquitously and reproducibly expressed from the murine BAC transgene in all organs and tissues analyzed, including the hematolymphoid compartment. Using this new reporter strain in hematopoietic cell transplantation studies, it is demonstrated that leukocytes in recipients maintain uniform transgene expression and are easily distinguished by flow cytometric analysis of live cells. The results suggest that the ROSA26 BAC is an efficient strategy for expressing complex transgene cassettes in vivo. genesis 45:83–89, 2007. Published 2007 Wiley‐Liss, Inc.
Automated ultrasound‐assisted method for the determination of the oxidative stability of virgin olive oil
Authors: Platero‐López José , García‐Mesa José A. 
Published: January 2007

AbstractA fast and automated method is proposed for determining the oxidative stability of virgin olive oil by using ultrasound. The ultrasound microprobe (3 mm in diameter) was directly immersed into the olive oil sample contained in a test tube. The most influential variables in the oxidation process, namely pulse amplitude, duty cycle, irradiation time, and sample amount, were optimized. The oil absorbance at 270 nm was continuously monitored by oil recirculation through a 0.1‐mm path length flow cell connected to a fiber optic microspectrometer. This short path length allowed the direct monitoring of absorbance without needing any sample dilution. The ultrasound energy was applied during 35 min, and the resulting increase in absorbance was continuously monitored. The difference between the final and the initial absorbance at 270 nm of a set of virgin olive oil samples was closely correlated with their oxidative stability calculated by the Rancimat method (R2 = 0.9915). The resulting equation enabled the prediction of the oxidative stability of virgin olive oil in a short period of time (35 min), by using a simple, inexpensive, automatic and easy‐to‐use system.
Electrochemical Synthesis and Characterization of 1,2‐Naphthaquinone‐4‐Sulfonic Acid Doped Polypyrrole
Authors: Akinyeye Richard Odunayo , Michira Immaculate , Sekota Mantoa , Ahmed Amir Al , Tito Duarte , Baker Priscilla Gloria Lorraine , Brett Christopher Michael Ashton , Kalaji Maher , Iwuoha Emmanuel 
Published: February 2007

AbstractPolypyrrole thin film microelectrodes prepared from an aqueous solution of the sodium salt of 1, 2‐napthaquinone‐4‐sulfonic acid and pyrrole in hydrochloric acid as the supporting electrolyte was characterized electrochemically for the first time and found to exhibit good electronic and spectroscopic properties. Voltammetric investigations showed that the polymer exhibited quasireversible kinetics in a potential window of −400 mV to 700 mV, with a formal potential of 322 mV vs. Ag/AgCl. The diffusion coefficient was calculated to be 1.02×10−6 cm2 s−1 for a thin film with a surface concentration of 1.83×10−7 mol cm−2 having a rate constant of 2.20×10−3 cm s−1 at 5 mV s−1. Electrochemical impedance spectroscopy provided quantitative information about the conductivity changes within the modified polymer and support for the quasireversible kinetics suggested by voltammetry. The changes in electrical properties of the polymer during electrochemical p‐doping and n‐doping were quantified by equivalent electrical circuit fitting and assisted in the identification of the suggested kinetic mechanism. SNIFTIRS confirmed the incorporation of the surfactant into the polypyrrole film and for the first time structural changes within the polymer were observed that could be related to the observed electrochemistry of the polymer.