bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of respiratory symptoms with dual pH monitoring in patients with gastro-oesophageal reflux disease
Authors: Kauer W K H , Stein H J , Möbius C , Siewert J R
Published: April 2004

Background

Gastro-oesophageal reflux disease (GORD) is a commonly underestimated aetiological factor in patients with respiratory symptoms. In this study, acid reflux in healthy volunteers and patients with GORD with and without respiratory symptoms was investigated by dual pH monitoring.

Methods

Thirty healthy volunteers and 43 patients with GORD underwent oesophageal manometry and dual pH monitoring with one probe in the proximal and one in the distal oesophagus. Nineteen of the 43 patients complained of respiratory symptoms.

Results

There were no differences in proximal probe measurements between volunteers and patients without respiratory symptoms. Patients with GORD and respiratory symptoms had a higher prevalence of abnormally high exposure to gastric juice and more reflux episodes in the proximal oesophagus compared with patients with GORD and no respiratory symptoms. Some 17 of 19 patients with GORD and respiratory symptoms showed deteriorated oesophageal body motility.

Conclusion

Dual pH monitoring is feasible and well tolerated, and provides an objective means of evaluating patients with GORD and respiratory symptoms. Prolonged exposure of the proximal oesophagus to gastric juice and disorders of oesophageal body motility seem to be responsible for the development of respiratory symptoms.
Advantages of laparoscopic stented choledochorrhaphy over T-tube placement
Authors: Isla A M , Griniatsos J , Karvounis E , Arbuckle J D
Published: April 2004

Background

Postoperative complications after laparoscopic choledochotomy are mainly related to the T tube. Both laparoscopic endobiliary stent placement with primary closure of the common bile duct (CBD) and primary closure of the CBD without drainage have been proposed as safe and effective alternatives to T-tube placement.

Methods

This was a retrospective analysis of data collected prospectively on 53 consecutive patients suffering from proven choledocholithiasis who underwent laparoscopic CBD exploration through a choledochotomy between January 1999 and January 2003. In the early period a T-tube was placed at the end of the procedure (n = 32). Biliary stent placement and primary CBD closure was performed from June 2001 (n = 21).

Results

There were no significant differences in epidemiological characteristics, preoperative factors or intraoperative findings between the groups. Seven patients developed complications, six in the T-tube group and one in the stent group. Univariate analysis revealed a significantly lower morbidity rate and shorter postoperative hospital stay in the stent group.

Conclusion

Placement of a biliary endoprosthesis after laparoscopic choledochotomy achieves biliary decompression, and avoids the complications of a T tube, leading to a shorter postoperative hospital stay. The method is a safe and effective alternative method of CBD drainage after laparoscopic choledochotomy.
Nosocomial infection
Authors: Leaper D
Published: April 2004

Patient Safety Leading Article Series, 2004. This leading article continues our series on the general topic of patient safety. In the last issue of BJS the dysfunctional professional relationship was highlighted and the way the airlines have tried to counter the associated risks. The present article examines patient risk from an entirely different viewpoint. Nosocomial infection has been with us ever since hospitals were invented but there are problems particular to the modern era. Professor David Leaper comments on today's risks.
DNA‐Computer — Superrechner der Zukunft?: Chemie und Informatik
Authors: Borchard‐Tuch Claudia
Published: April 2004

Seit kurzem wird ein neuer Weg beschritten, sich die Eigenschaften natürlicher Informationssysteme zunutze zu machen. Man hat Computer entwickelt, deren informationsverarbeitende Bauelemente Desoxyribonukleinsäure (DNA) ist. Diese Computer ermöglichen eine dreidimensionale und parallele Verarbeitung von Informationen. Aufgrund der zahlreichen parallelen chemischen Reaktionen kann ein DNA‐Computer Probleme lösen, die elektronische Computer nicht bewältigen können. Welche Möglichkeiten in DNA‐Computern liegen, konnte mittlerweile gezeigt werden: Da ein DNA‐Computer ebenso gut wie eine universelle Turing‐Maschine funktioniert, beweist dies seine grundsätzliche Fähigkeit, jedes Computerprogramm auszuführen.
Funktionelle Lebensmittel: Mehr als ein Trend?
Authors: Kunz Clemens , Schulz Sabine
Published: April 2004

Lebensmittel sind dann funktionell, wenn sie einen über die normale Nährstoffzufuhr hinausgehenden Zusatznutzen aufweisen. Für präventive Maßnahmen scheinen insbesondere Carotinoide, Polyphenole und Phytosterole ein hohes Potential zu haben. Inwieweit hier jedoch isolierte Substanzen eingesetzt werden können, ist noch nicht ausreichend untersucht. Von größerer Bedeutung sind natürliche Lebensmittel, die garantieren, dass auch Inhaltsstoffe aufgenommen werden, von denen möglicherweise biologische Funktionen ausgehen, die wir heute noch gar nicht kennen.
Die Leiden des cand. chem. Donald Duck
Authors: Roth Klaus
Published: April 2004

Was macht einen guten und erfolgreichen Wissenschaftler aus? Talent? Fleiß? Geduld? Glück? Zufall? Geld? Beziehungen? Wie viele von uns, sucht auch der legendäre Donald Duck nach der „Seele der Wissenschaft”︁.
Aufstieg und Niedergang des Galaliths
Authors: Krätz Otto
Published: April 2004

Hochschullehrer pflegen gegenüber ihren Studenten mit einem gewissen Ernst stets die eminente Nützlichkeit tiefer theoretisch‐chemischer Kenntnisse zu betonen. Bei historischen Betrachtungen muss man jedoch gelegentlich gestehen, dass die Entdecker eines einstmals wichtigen Produktes keinerlei wie auch immer geartete Kenntnisse chemischer Strukturen und schon gar nicht von Reaktionsmechanismen hatten. Besonders unangenehm ist, dass man als Chemiehistoriker dann auch noch zugeben muss, dass diese Entdecker zwar keine Ahnung hatten, dafür aber beträchtliches Geld verdienten. Offenbar galt zumindest früher in der Praxis: Theorie ist schön, eine gute Idee ist besser!
Edle Schichten für die Brille
Authors: Borchard‐Tuch Claudia
Published: April 2004

Kratzfest, entspiegelt und wasserabweisend — so sollte ein hochwertiges Brillenglas sein. Die moderne Oberflächentechnik macht dies möglich.
Biologische Chemie
Authors: Höfker Uwe
Published: April 2004

Das Internet bietet mannigfaltige Möglichkeiten für multimediale Unterstützung in der Lehre. In diesem Beitrag liegt der Schwerpunkt im Bereich der biologischen Chemie und der Darstellung von großen Biomolekülen wie Proteinen.
Möbius‐Aromaten
Authors: Groß Michael
Published: April 2004

Das Möbius‐Band hat, wie Freunde mathematischer Kopfnüsse bereits wissen, nur eine Oberfläche und eine Kante. Man erhält es, indem man einen langen Papierstreifen zu einem Ring biegt, dann aber eines der Enden um 180 Grad dreht, bevor man beide zusammenklebt. Ähnliche Spielereien mit Papierstreifen brachten den Kieler Chemiker Rainer Herges auf die Idee, wie man ein molekulares Möbiusband herstellen und damit ein Jahrzehnte altes Problem lösen kann [1].
Wie die Stechmücken menschlichen Schweiß orten
Authors: Jacoby Petra
Published: April 2004

Dass Moskitos ihre Opfer mit Hilfe des Geruchssinns aufspüren, ist schon seit längerem bekannt. Jetzt liefert eine Studie Einblicke in den molekularen Mechanismus dieses Phänomens und könnte zur Entwicklung neuer Mittel gegen die Blutsauger beitragen.
Incidence of chemotherapy‐induced nausea and emesis after modern antiemetics
Authors: Grunberg Steven M. , Deuson Robert R. , Mavros Panagiotis , Geling Olga , Hansen Mogens , Cruciani Giorgio , Daniele Bruno , De Pouvourville Gerard , Rubenstein Edward B. , Daugaard Gedske
Published: April 2004

BACKGROUND

The authors determined the incidence of acute and delayed chemotherapy‐induced nausea and emesis (vomiting) (CINV) among patients receiving highly (HEC) or moderately (MEC) emetogenic chemotherapy. They also assessed whether physicians and nurses accurately recognized the incidence of acute and delayed CINV in their own practices.

METHODS

A prospective, observational study of adult patients receiving HEC or MEC for the first time was performed. Before patient enrollment, medical oncologists and oncology nurses estimated the incidence of acute (Day 1) and delayed (Days 2–5) CINV after first administration of HEC and MEC in their own practices. Eligible patients from their practices then completed a 6‐day diary including emetic episodes, nausea assessment, and antiemetic medication use. Observed incidence rates of acute and delayed CINV were compared with physician/nurse predictions.

RESULTS

Twenty‐four physicians and nurses and 298 eligible patients (67 receiving HEC and 231 receiving MEC) were recruited from 14 oncology practices in 6 countries. Greater than 35% of patients overall experienced acute nausea, whereas 13% experienced acute emesis. Delayed nausea and emesis were observed in 60% and 50% of HEC patients, respectively, and in 52% and 28% of MEC patients, respectively. Delayed symptoms appeared without acute symptoms after HEC (emesis, 38%; nausea, 33%) and MEC (emesis, 19%; nausea, 21%). Physicians and nurses accurately predicted the incidence of acute CINV but underestimated the incidence of delayed nausea and emesis after HEC by 21 and 28 percentage points, respectively, and delayed nausea after MEC by 28 percentage points. Greater than 75% of physicians and nurses underestimated the incidence of delayed CINV after both HEC and MEC.

CONCLUSIONS

Physicians and nurses markedly underestimated the incidence of delayed nausea and emesis after both HEC and MEC. Delayed nausea and emesis, which may appear even in the absence of acute nausea and emesis, remain important targets for improved therapeutic intervention. Cancer 2004. © 2004 American Cancer Society.
QoS routing through alternate paths in wirelessad hocnetworks
Authors: Zhang Baoxian , T. Mouftah Hussein
Published: April 2004

Quality of service (QoS) routing plays an important role in QoS provisioning for mobilead hocnetworks. This work studies the issue of route selection subject to QoS constraint(s). Our method searches for alternate routes with satisfied QoS requirement(s) to accommodate each communication request when the shortest path connecting the source–destination pair of the request is not qualified. In order to effectively reduce protocol overhead, a directed search mechanism is designed to limit the breadth of the searching scope, which aims at achieving a graceful tradeoff between the success probability in QoS route acquisition and communication overhead. Efficient hop‐by‐hop routing protocols are designed for route selection subject to delay and bandwidth constraint, respectively. Simulation results show that the designed protocols can achieve high performance in acquiring QoS paths and in efficient resource utilization with low control overhead. Copyright © 2004 John Wiley & Sons, Ltd.
The hopcount to an anycast group
Authors: Mieghem Piet Van
Published: April 2004

The probability density function of the number of hops to the most nearby member of the anycast group consisting of m members (e.g. servers) is analysed. The results are applied to compute a performance measure η of the efficiency of anycast over unicast and to the server placement problem. The server placement problem asks for the number of (replicated) servers m needed such that any user in the network is not more than j hops away from a server of the anycast group with a certain prescribed probability. Two types of shortest path trees are investigated: the regular k‐ary tree and the irregular uniform recursive tree. Since these two types of trees indicate that the performance measure η ≈ 1 − a log m where the real number a depends on the details of the tree, it suggests that for trees in real networks (as the Internet) a same logarithmic law applies. An order calculus on exponentially growing tree further supplies evidence for the conjecture that η ≈ 1 − a log m for small m. Copyright © 2004 John Wiley & Sons, Ltd.
Modelling multi‐dimensional QoS: some fundamental constraints
Authors: Liu Nelson X. , S. Baras John
Published: April 2004

In this paper, we model multi‐dimensional QoS in a unified framework, and study some fundamental constraints from the network and the traffic on realizing multiple QoS goals. Multi‐dimensional QoS requirements are quantitatively represented using a QoS region. Based on the theory of effective bandwidths, the framework connects the throughput, the delay, and the loss rate in a uniform formula. Important traffic and network factors, namely, the burst size and the link speed, are involved. With this framework, it is found that the burst size sets hard limit on the QoS region that can be achieved, and that the matching between the link speed and the node processing power can greatly improve the limit. It is also made clear that while pure load imbalance among links does not affect the QoS region, the heterogeneities of burst size or link speed may severely degrade the QoS performance. Applying the theory to real‐time services in differentiated services architecture, we show it provides a useful tool for QoS prediction and network dimensioning. Copyright © 2004 John Wiley & Sons, Ltd.
Optimal design method for selective nerve stimulation
Authors: Kajimoto Hiroyuki , Kawakami Naoki , Tachi Susumu
Published: April 2004

This paper discusses selective stimulation, which is a problem common to various electrical stimulation techniques. The induction of nerve activity by electrical stimulation is a technique which is widely used in medical and health care. In order to reduce unpleasant feelings during stimulation and to diversify the induced sensations, it is necessary to control the stimulus waveform and to design the electrode in appropriate ways. From the viewpoint of nerve stimulation, the above requirement can be interpreted as a selective stimulation problem in which the target nerve fiber is stimulated and the activities of other nerves are minimized. At the present stage of electrical stimulation, however, there is no means of representing selectivity of stimulation mathematically, although precise modeling of the stimulus site is possible. Consequently, the design for selective stimulation is based on trial and error. The purpose of this paper is to construct a mathematical framework for the design of selective stimulation. The requirement for selective stimulation is formulated as a quadratic programming problem which gives a route to the optimal stimulation technique. Several simple examples are solved, and the usefulness of the proposed method is shown through comparison to selective stimulation techniques that were proposed in the past. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 62–72, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20098
Machine translation method using inductive learning for mobile terminal
Authors: Matsuhara Masafumi , Araki Kenji , Tochinai Koji
Published: April 2004

The authors propose a machine translation technique for a compact terminal such as a mobile telephone. With a compact terminal that emphasizes portability such as a mobile phone, the number of keys that the terminal can be equipped with is necessarily restricted by the limited size of the terminal itself. Therefore, to enable input by using only this small number of keys, the proposed technique assigns multiple characters to a single input key. In addition, to enable rapid input, a single character is entered by a single key‐press. As a result, the number sequence that is the input string to the proposed technique is associated with multiple character strings, and thus there also exist multiple translation candidates for this number sequence, thereby increasing ambiguity. Nevertheless, by using inductive learning, the proposed technique can automatically acquire translation rules that depend on the subject and use these rules for translation. This high level of adaptability enables the proposed technique to eliminate ambiguity as much as possible during the translation process to obtain a correct translation. The authors created a system based on the proposed technique and assigned a small number of word translation rules in advance to perform Japanese‐to‐English machine translation experiments. The results verified the effectiveness of the proposed technique by showing that the final translation precision of approximately 70% and the translation efficiency were high. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 87(9): 33–47, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20100
Space charge distribution for various glass materials under DC stress
Authors: Miyake Hiroaki , Ito Yuuki , Tanaka Yasuhiro , Takada Tatsuo , Hanai Masahiro
Published: April 2004

Space charge accumulation for various glass materials under DC stress was studied by using a pulse electroacoustic (PEA) method. We should make an acoustic matching between the sample and electron on the high‐voltage side when the hetero‐space charge distribution in glass materials is measured. The acoustic pressure wave generated from the induced charge at the high‐voltage side is canceled by the reflected one generated from hetero‐charge accumulated in the sample. Large hetero‐charge is observed in the glass materials containing MgO and CaO compound compared to the quartz glass containing no such compounds. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 19–27, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10260
A study of capacitive current switching capability by flashover characteristics between contacts of circuit breakers
Authors: Toyoda Mitsuru , Aoyagi Hirokuni , Mizoguchi Hitoshi
Published: April 2004

This paper describes the capacitive current interruption capability of circuit breakers from the viewpoint of flashover characteristics between the contacts of breakers. The authors obtained flashover characteristics between the contacts having a short gap between them by comparing the data for new contacts and the data for contacts eroded after having been exposed to three interruptions at T60 according to amended regulations JEC 2300 (1998) and IEC 62271‐100 (2001). Comparison of the flashover characteristics and the electric field calculations obtained by measurements using new and eroded contacts have shown that the deterioration of dielectric strength amounts to 10 to 20%. The authors also conducted flashover tests for the contacts and nozzle after a significant number of interruptions. The total number of interruptions can be considered as the maximum possible number of interruptions according to CIGRE research. The deterioration of dielectric characteristics is 10 to 30%. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 28–37, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10281
Robustness of the multigrid method for edge‐based finite element analysis
Authors: Watanabe Kota , Igarashi Hajime , Honma Toshihisa
Published: April 2004

The dependence of the multigrid finite element method solving three‐dimensional magnetostatic fields on the quality of the finite element mesh is reported. It is shown that the convergence of the multigrid method is strongly influenced by the mesh quality. Moreover, the multigrid method with ICCG smoother is shown to be more robust against mesh distortion than that with Gauss–Seidel and SOR smoothers. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 75–81, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10289
A highly efficient contactless electrical energy transmission system
Authors: Ayano Hideki , Nagase Hiroshi , Inaba Hiromi
Published: April 2004

This paper proposes a new concept for contactless electrical energy transmission system for an elevator and an automated guided vehicle. The system has rechargeable batteries on the car and electrical energy is supplied at a specific place. When electric power is supplied to the car, it runs automatically and approaches the battery charger. Therefore, a comparatively large gap is needed between the primary transformer at the battery charger and the secondary transformer on the car in order to prevent damage which would be caused by a collision. In this case, a drop of the transformer coupling rate due to the large gap must be prevented. In conventional contactless electrical energy transmission technology, since electric power is received by a pickup coil from a power line, a large‐sized transformer is required. When the distance over which the car runs is long, the copper loss of the line also increases. The developed system adopts a high‐frequency inverter using a soft switching method to miniaturize the transformer. The system has a coupling rate of 0.88 for a transformer gap length of 10 mm and can operate at 91% efficiency. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 66–74, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10290
Position control for a linear slider with twin linear drives
Authors: Nakashima Ray , Hao Shuanghui , Honda Hideki , Oguro Ryuichi , Miyakawa Hidekazu , Tsuji Teruo
Published: April 2004

In this paper, position control of a linear slider with twin linear drives is considered. Recently, for high‐speed response, several linear motors have been used for linear slider systems.

In such a linear slider, if the linear drives are controlled individually, their position responses may undergo vibrational disturbance by interaction with the output of the motors. To control this vibration, this paper presents a dynamic model of a linear slider system which consists of two motion systems decoupled by coordinate transformation, and proposes a feedback controller which is designed for these two decoupled systems. The effectiveness of the proposed method is confirmed by experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 68–76, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10291
Effective constitutive parameters of a random medium containing small chiral spheres
Authors: Nanbu Yukihisa , Matsuoka Tsuyoshi , Tateiba Mitsuo
Published: April 2004

We have analyzed the effective constitutive parameters for a random medium containing small chiral spheres embedded in an achiral background medium by using our approach. The approach is based on an unconventional multiple scattering method by which wave scattering can be systematically treated in a medium whose dielectric particles are randomly displaced from a uniformly ordered spatial distribution. We have clarified the characteristics of the effective medium parameters by changing the volume fraction and constitutive parameters of chiral spheres. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 11–18, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10294
Three‐dimensional finite element eddy current analysis by using high‐order vector elements
Authors: Hano Mitsuo , Miyamura Takeshi , Hotta Masashi
Published: April 2004

Sets of high‐order basis functions of a tetrahedral element are systematically constructed and applied to finite element analysis of eddy current problems. A polynomial space is divided into a lot of subspaces assigned on the edges, faces, and a volume of the tetrahedral element. Lagrange‐type vector basis functions of the subspaces are presented. The effect of the high‐order vector elements is investigated by a cubic conductor model located in AC steady‐state magnetic fields. In the calculations using the fundamental and second‐order elements, no convergent value of the eddy current power loss can be obtained in spite of fine meshes because the eddy current shifts to the surface of the conductor. The higher‐order vector elements give the convergent solutions in the coarse meshes. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 60–67, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10306
Performance evaluation of SOFC systems using electrochemical partial oxidation of methane
Authors: Yokoo Masayuki , Take Tetsuo , Ohtsu Satoshi
Published: April 2004

We simulated the performance of systems using a solid oxide fuel cell (SOFC) stack which generates electricity by electrochemical partial oxidation of methane and a conventional steam‐reforming‐type SOFC (SRSOFC) stack. The net thermal efficiency in an atmospheric partial‐oxidation‐type SOFC (POSOFC)‐SRSOFC system was 8% higher than that in an atmospheric SRSOFC system at system outputs of 35 kW or more. The net thermal efficiency of a pressurized POSOFC‐SRSOFC‐gas turbine (GT) system was slightly higher than that of a pressurized SRSOFC‐GT system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 11–19, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10314
Transient current analysis of induction generators for wind power generating system
Authors: Senjyu Tomonobu , Sueyoshi Norihide , Uezato Katsumi , Fujita Hideki
Published: April 2004

In this paper we present a transient current analysis of induction generators used in a wind power system before and after three‐phase fault conditions. First, the basic equations of an induction generator connected to an infinite bus are developed and then transient current analysis formulas are derived for a three‐phase fault before and after fault clearance. We also determine the initial phase angle for the three‐phase fault or the restoration phase angle of the power supply voltages and the time at which the maximum or minimum transient currents flow in the system. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(1): 38–45, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10319
Enantiomerically Pure Amines as Substrates for the Ti‐Catalyzed Hydroamination of Alkynes
Authors: Pohlki Frauke , Bytschkov Igor , Siebeneicher Holger , Heutling Andreas , König Wilfried A. , Doye Sven
Published: April 2004

For two representative reactions employing enantiomerically pure (S)‐1‐phenylethylamine and (S)‐1‐cyclohexylethylamine it is shown that Ti‐catalyzed hydroamination reactions of alkynes do not generally take place without partial racemization at the chiral center adjacent to the nitrogen atom. However, identified from a selection of nine Ti catalysts, Cp*2TiMe2 and at least two other catalysts can be used for racemization‐free hydroamination reactions of alkynes. Furthermore, the amount of racemization can be reduced significantly by the addition of pyridine to the reaction mixture. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Amphiphilic Amide Derivatives of D‐Glucaric Acid. Synthesis and Complexing Properties Toward Lanthanide(III) Ions
Authors: Aury Sabrina , Rubini Patrice , Gérardin Christine , Selve Claude
Published: April 2004

Hydrophobic derivatives of D‐glucaric acid, HOOC−(CHOH)4−CONHR,where R is an alkyl chain having 3, 8, 10, or 12 carbon atoms, have been synthesized from D‐glucaro‐1,4‐lactone and the corresponding amines. The complexing abilities of these compounds toward trivalent lanthanide cations have been studied, using the water‐soluble propyl compound, and compared to that of gulonic acid, which corresponds to the complexing part of these molecules. The formation constants of the complexes have been determined and their structures discussed. The surfactant properties of the C8, C10 and C12 glucaramides and their extracting ability toward LnIII ions have also been evaluated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Enantioselective Synthesis of the Originally Proposed Usneoidone Structure: Evidence for a Structural Revision
Authors: Danet Michèle , Normand‐Bayle Marie , Mahuteau Jacqueline , d'Angelo Jean , Morgant Georges , Desmaële Didier
Published: April 2004

The enantioselective synthesis of the initially proposed structure of usneoidone has been completed according to a convergent strategy in which the key steps were an enantioselective Michael addition involving chiral imines to set up the C12 quaternary center, and the final assembly of the chiral pyran moiety with the aromatic subunit through a cyanohydrin anion alkylation step. The obtained product displays spectroscopic data that significantly differ from the reported values. A putative revised structure in which the pyran ring is opened is proposed for usneoidones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis of Macrocyclic Carbonates with Musk Odor by Ring‐Closing Olefin Metathesis
Authors: Michrowska Anna , Wawrzyniak Piotr , Grela Karol
Published: April 2004

This study shows the efficiency of modern well‐defined ruthenium catalysts for the formation of musk‐odored macrocyclic carbonates with ring sizes between 15−23 atoms. It also reveals that, in these cases, geometric factors are very important and that smaller ring carbonates are difficult to access by ring closing metathesis, even with highly active second‐generation ruthenium catalysts. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis and NMR Structural Analysis of 2′‐OMe‐Uridin‐3′‐yl (3′,5′)‐5′‐O‐(N‐Isobutyryl‐2′‐OMe‐Cytidine) Methylthiophosphonates
Authors: Olejniczak Sebastian , Potrzebowski Marek J. , Wozniak Lucyna A.
Published: April 2004

Detailed analysis of the molecular structures of both the Fast‐eluted and the Slow‐eluted (the notation Slow and Fast corresponds to the relative mobility properties of compounds in silica gel column chromatography under normal phase conditions, see Exp. Sect. for details) diastereomers of 5′‐OH‐2′‐OMe‐uridin‐3′‐yl (3′,5′)‐5′‐O‐(N‐isobutyryl‐2′‐OMe‐cytidine) methylthiophosphonate (1) was performed with the aid of 1H, 13C, 1D and 2D homo‐ and heteronuclear PFG (Pulse Field Gradient) NMR studies. The absolute configurations [(RP) and (SP)] of the diastereomers of 1 were unambiguously assigned by 1H ROESY experiments. The pseudorotation parameters of the ribose ring were calculated with the aid of the PSEUDOROT program, and compared with data obtained from X‐ray structure analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis of 2,4‐Furanophanes by Palladium‐Catalyzed Macrocyclization Reactions of 1,n‐Diallenyl Diketones
Authors: Hashmi A. Stephen K. , Schwarz Lothar , Bolte Michael
Published: April 2004

The 1,n‐diallenyl diketones 8a−j were prepared and subjected to reactions with the [PdCl2(MeCN)2] catalyst. Upon decreasing the length of the bridge between the allenyl ketone units, first we obtained the (E) isomer 10 as the macrocyclic product and then the (Z) isomer 11 accompanied by the exocyclic double bond isomer 12. In all cases, the open‐chained 1,n‐difuryl alkanes were isolated as side‐products. The analogous preparation and conversion of the diallenyl diketones 19 and 24, which have even longer bridges and ether‐functionalities, delivered the 20‐ to 52‐membered macrocycles 21a, 21b, 26a, and 26b with only the expected (E) configuration of the double bond. The ring closure of a furan derivative, having vinyl groups in its substituents at the 2‐ and 4‐positions, to a related product by Ru‐catalyzed olefin metathesis delivered yields similar to the Pd‐catalyzed macrocyclization, but provided a mixture of both double bond isomers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Design of Strong, Neutral Organic Superacids: DFT‐B3LYP Calculations on Some Isobenzofulvene Derivatives
Authors: Maksić Zvonimir B. , Vianello Robert
Published: April 2004

Isobenzofulvenes heavily substituted by cyano groups provide very good candidates for neutral organic superacids of unprecedented strength. The latter can be additionally enhanced by the anionic corona effect realized by interaction between the propyl−BX2 chain, where X = F, Cl and Br, and the O− atom in the corresponding conjugate bases. The main reason for the highly pronounced acidity is found, however, in the aromatization of the isobenzofulvene moiety upon deprotonation, which, in turn, is assisted by the electron‐withdrawing CN groups. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Desymmetrization of Prochiral Phosphanes Using Derivatives of (−)‐Cytisine
Authors: Johansson Magnus J. , Schwartz Lennart O. , Amedjkouh Mohamed , Kann Nina C.
Published: April 2004

Historically, (−)‐sparteine·sec‐BuLi has been used to desymmetrize prochiral phosphanes. In this report, derivatives of an alkaloid extracted from the seeds of Laburnum anagyroides have been utilized to mimic (+)‐sparteine, which is not readily available. In several cases, the enantioselectivities achieved with the (+)‐sparteine surrogates outperformed (−)‐sparteine itself in the deprotonation of alkyl‐substituted (as well as aryl‐substituted) prochiral phosphane derivatives. In addition, use of these surrogates allows a new methodology for a chiral switch in phosphorus chemistry. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Chiral Configurations of Spirane‐Bridged Cyclotriphosphazenes
Authors: Coles Simon J. , Davies David B. , Eaton Robert J. , Hursthouse Michael B. , Kılıç Adem , Shaw Robert A. , Uslu Aylin
Published: April 2004

The stereogenic properties of carbocyclic spiranes with two interlocking rings are well‐established. Although some cyclophosphazene analogues of dispiranes have been reported, the molecules did not have any centres of chirality because they were symmetrically substituted. Linear tetraspiranes, in which the two inner rings are carbocyclic and symmetrical and the two outer rings are unsymmetrically‐substituted cyclotriphosphazenes, are expected to give rise to chiral molecules. We now report on the synthesis and stereogenic properties of the three structural types of pentaerythritol‐bridged disubstituted cyclophosphazenes, which all have centres of chirality. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Proteomic analysis of differential protein expression in a human hepatoma revertant cell line by using an improved two‐dimensional electrophoresis procedure combined with matrix assisted laser desorption/ionization‐time of flight‐mass spectrometry
Authors: Yuan Quan , An Jie , Liu Ding‐gan , Sun Li , Ge Ying‐zi , Huang Ying‐ling , Xu Gen‐jun , Zhao Fu‐kun
Published: April 2004

The proteomic profiles of a human hepatoma revertant, CL1, and its original cell line, SMMC7721, were compared by using an improved two‐dimensional electrophoresis (2‐DE) procedure, with multi‐IPGstrips gels (length ≤ 13 cm) run simultaneously on one sodium dodecyl sulfate (SDS) gel (shortened MSOG method). Nineteen proteins, showing significant difference in expression (P < 0.01), were selected and identified by matrix assisted laser desorption/ionization‐time of flight‐mass spectrometry (MALDI‐TOF‐MS) and database search. In the revertant CL1 cells, compared to human hepatoma SMMC7721 cells, upregulated expression levels of some proteins related to tumor suppression, like maspin, were found, whereas some proteins related to tumor growth, like cathepsin D, were downregulated. These facts suggest that the phenotypic reversion of the CL1 cells was at least partially due to changes at the translational level of the proteins which favored the reconstruction of the normal phenotype of the cell.
Comprehensive proteome analysis by chromatographic protein prefractionation
Authors: Lescuyer Pierre , Hochstrasser Denis F. , Sanchez Jean‐Charles
Published: April 2004

Protein copy number is distributed from 7 to 8 orders of magnitude in cells and probably up to 12 orders of magnitude in plasma. Classical silver‐stained two‐dimensional electrophoresis (2‐DE) can only display up to four orders of magnitude. This is a major drawback since it is assumed that most of the regulatory proteins are low‐abundance gene products. It is thus clear that the separation of low copy number proteins in amounts sufficient for postseparation analysis is an important issue in proteome studies to complete the comprehensive description of the proteome of any given cell type. The visualization of a polypeptide on a 2‐DE gel will depend on the copy number, on the quantity loaded onto the gel and on the method of detection. As the amount of protein that can be loaded onto a gel is limited, one efficient solution is to fractionate the sample prior to 2‐DE analysis. Several approaches exist including subcellular fractionation, affinity purification and chromatographic and electrophoretic protein prefractionation. The chromatographic step adds a new dimension in the protein separation using specific protein properties. It allows proteins to be adsorbed to a surface and eluted differentially under certain conditions. This review article presents studies combining chromatography‐based methods to 2‐DE analysis and draws general conclusions on this strategy.
Determination of creatinine in human serum by short‐end injection capillary zone electrophoresis
Authors: Zinellu Angelo , Carru Ciriaco , Usai Maria F. , Sotgia Salvatore , Deiana Luca
Published: April 2004

A new ultra‐rapid free‐solution capillary zone electrophoresis method to measure serum creatinine is presented. Procedural parameters such as injection mode, concentration and pH of phosphate running buffer and acidic deproteinization of serum samples were investigated. Short‐end injection permits a decrease of the analysis time by injecting samples at the outlet end of a silica capillary closest to the detection window, so reducing the migration distance. Thus, when a capillary with an effective length of 10.2 cm and a 40 mmol/L sodium phosphate buffer pH 2.35 was used, the obtained migration time of the creatinine peak was the shortest never described before, about 1.1 min. These conditions give a good reproducibility of the migration times (coefficient of variation, CV% < 0.5) and the peak areas (CV% < 2.8). Intra‐ and interassay CV were 3.06 and 6.26%, respectively, and analytical recovery was 99.4%. We compared our proposed method to Jaffé colorimetric assay, by measuring serum creatinine in 128 normal subjects. The obtained data were analyzed by the Passing and Bablok regression and Bland‐Altman test. Creatinine concentration in healthy subjects was also used to investigate on its relationships with plasma thiols levels.
Chiral capillary electrophoretic resolution of baclofen, gabaergic ligand, using highly sulfated cyclodextrins
Authors: Vaccher Marie‐Pierre , Lipka Emmanuelle , Bonte Jean‐Paul , Vaccher Claude
Published: April 2004

Using cyclodextrin‐capillary zone electrophoresis (CD‐CZE), baseline separation of baclofen, a potent GABAB agonist; was achieved. A method for the enantioresolution of this γ‐aminobutyric acid (GABA) and determination of enantiomeric purity was developed using CDs (highly sulfated‐CD or highly S‐CD) as chiral selectors and capillaries dynamically coated with polyethylene oxide (PEO). Operational parameters, such as the nature and concentration of the chiral selectors, buffer concentration, organic modifiers, and applied voltage, were investigated. The use of charged CDs provides a driving force in the opposite direction of the positively charged baclofen in the running buffer and enantiomeric resolution by inclusion of compounds in the CD cavity. Highly S‐β‐CD was found to be the most effective complexing agent, allowing good enantiomeric resolution. The complete resolution was obtained using 25 mM phosphate buffer, pH 2.5, containing 3% w/v highly S‐β‐CD at 25°C with aN applied field of 0.40 kV/cm. The apparent association constants of the inclusion complexes were calculated. This optimized method was validated in terms of repeatability and limits of detection (0.13 μg·mL−1) and quantification. The migration order was determined.
Discontinuous buffer systems operative at pH 2.5 – 11.0, 0°C and 25°C, available on the Internet
Authors: Wheeler David , Chrambach Andreas , Ashburn Patricia , Jovin Thomas M.
Published: April 2004

This communication is an announcement of the availability on the Internet of a computer output of discontinuous buffer systems operative at pH 2.5–11.0, 0°C and 25°C, generated by the theory and program of T. M. Jovin. The output and instructions for its use can be accessed under http://www.buffers.nichd.nih.gov.
Determination of different forms of human interferon‐γ in single natural killer cells by capillary electrophoresis with on‐capillary immunoreaction and laser‐induced fluorescence detection
Authors: Zhang Hua , Jin Wenrui
Published: April 2004

A novel method for determining different forms of human interferon‐γ (IFN‐γ) in single natural killer cells was developed by capillary electrophoresis (CE) with on‐capillary immunoreaction and laser‐induced fluorescence (LIF) detection. Cells were perforated with digitonin and one single cell was electrokinatically introduced into the front end of a separation capillary. The monoclonal antibody labeled with fluorescein isothiocyanate of IFN‐γ was hydrodynamically injected into the front end of the capillary around the cell introduced. After the cell was lysed by ultrasonication, the front end of the capillary was used as a microreactor to allow different forms of IFN‐γ to process the immunoreaction with their labeled antibody. Finally, the complexes of different forms of IFN‐γ with their labeled antibody were separated and detected by CE with LIF detection with a limit of detection of zeptomoles (10−21 mol).
Capillary electrophoresis using immobilized whole cells with overexpressed endothelin receptor for specific ligand screening
Authors: Yu Hui‐Ming , Tseng Min‐Jen , Fang Jim‐Min , Phutrakul Suree , Chen Shui‐Tein
Published: April 2004

A new capillary electrophoresis method using immobilized cells as the stationary phase has been developed. The power of this method is demonstrated by the separation and identification of endothelin antagonists on a capillary column coated by the transfected Chinese hamster ovary (CHO) cells with overexpressing endothelin receptors. The screening results are validated by functional assays suppressing the increase of intracellular calcium concentration induced by endothelin‐1. Instead of making efforts in isolating protein receptors, the easily prepared whole‐cell capillary column provides a superior tool on the basis of ligand/receptor affinity for a rapid screening of potent drug candidates from compound libraries.
Capillary zone electrophoresis of metal‐binding proteins in formic acid with UV‐ and mass spectrometric detection using cationic transient capillary isotachophoresis for preconcentration
Authors: Stutz Hanno , Bordin Guy , Rodriguez Adela Rosa
Published: April 2004

A capillary zone electrophoresis (CZE) method with preceding cationic transient capillary isotachophoresis (tCITP‐CZE) was developed for uncoated fused‐silica capillaries to analyze metal‐binding proteins (MBPs) of clinical relevance. UV detection was followed by mass spectrometry (MS). Optimization was done with model proteins of properties similar to relevant human MBPs. Using 1.0 mol·L−1 formic acid (pH 1.78) as electrolyte resulted in up to 165 000 plates m−1 in CZE and 230 000 plates m−1 in combination with tCITP and analysis time was less than 5 min in uncoupled mode. Cationic tCITP with 125 mmol·L−1 ammonium formate, buffered to pH 4.00, as leading electrolyte improved sample loadability considerably in comparison with sample stacking without impairing resolution. Following systematic optimization of the electrospray ionization process (ESI) the coupled system ((tCITP)‐CZE‐UV‐ESI‐MS) was tested with protein model mixtures and human MBPs. Repeatability of migration times was < 0.64% in pure CZE mode and in tCITP‐CZE mode and < 0.83% in CZE‐ESI‐MS coupled mode. Mass accuracy was < 0.015%. Limits of detection were found to be in the range 50–160 fmol.
Hybrid seismic protection of cable‐stayed bridges
Authors: Jung H.‐J. , Park K.‐S. , Spencer B. F. , Lee I.‐W.
Published: April 2004

This paper proposes a hybrid control strategy combining passive and semi‐active control systems for seismic protection of cable‐stayed bridges. The efficacy of this control strategy is verified by examining the ASCE first‐generation benchmark problem for a seismically excited cable‐stayed bridge, which employs a three‐dimensional linearized evaluation bridge model as a testbed structure. Herein, conventional lead–rubber bearings are introduced as base isolation devices, and semi‐active dampers (e.g., variable orifice damper, controllable fluid damper, etc.) are considered as supplemental damping devices. For the semi‐active dampers, a clipped‐optimal control algorithm, shown to perform well in previous studies involving controllable dampers, is considered. Because the semi‐active damper is a controllable energy‐dissipation device that cannot add mechanical energy to the structural system, the proposed hybrid control strategy is fail‐safe in that the bounded‐input, bounded‐output stability of the controlled structure is guaranteed. Numerical simulation results show that the performance of the proposed hybrid control strategy is quite effective in protecting seismically excited cable‐stayed bridges. Copyright © 2004 John Wiley & Sons, Ltd.
Managing Cold War historic structures: Mitigating impacts to a satellite‐tracking antenna at New Boston Air Force Station, New Hampshire
Authors: O'Rourke Daniel J. , Najjar Stephen J. , Elliott Joseph E. B.
Published: April 2004

It is the responsibility of all federal facilities to be the caretakers of any historic properties under their jurisdiction. When a significant historic structure will be adversely affected by a federal project, that impact must be mitigated. Such mitigation is generally achieved through documentation of the structure so that a written and visual record of the existing structure is saved for posterity. Argonne National Laboratory personnel recently documented a historically significant Cold War‐era satellite‐tracking antenna for the New Boston Air Force Station in New Hampshire. This antenna was slated for demolition. The procedure followed for identification of the property, the planning of the demolition, and the development of the documentation provides an example of how management of historic properties can be addressed without interfering with the mission activities. © 2004 Wiley Periodicals, Inc.
Life‐cycle cost in a highly uncertain economic environment: The case of managing the U.S. Department of Energy's nuclear waste legacy
Authors: Greenberg Michael , Mayer Henry , Lewis David
Published: April 2004

The U.S. Department of Energy (DOE) faces an unusually difficult challenge in estimating life‐cycle costs at former weapons sites because of the uncertainties of technology, stewardship, future land use, laws and regulations, and value and availability of money. Further, it is difficult to forecast local and international events for the indefinite period of time over which DOE will be responsible for many sites. We view the challenge as requiring an approach that accepts some variables as under DOE's control and others not under the Department's control. We suggest being as explicit as possible about the full set of cost elements and viewing life‐cycle cost estimation as a stochastic process that will require both detailed data analysis and interviews with experts to provide the basis upon which to produce plausible estimates. © 2004 Wiley Periodicals, Inc.