bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of juvenile hormone on vitellogenin gene expression in the fat body of burying beetles, Nicrophorus orbicollis
Authors: Panaitof S. Carmen , Scott Michelle Pellissier
Published: September 2006

In the burying beetles, Nicrophorus orbicollis, it is not clear the extent to which synthesis of Vitellogenin (Vg) is under hormonal control. Juvenile hormone (JH) and ovarian development increase rapidly upon discovery of a carcass, the necessary reproductive resource, but in its absence, treatment with JH does not accelerate ovarian development. Here we investigated the effect of manipulating JH titers on Vg gene expression in the fat bodies of newly eclosed and sexually mature females. Topical applications of the JH analogue methoprene at doses of 200, 300, and 400 μg of methoprene/g beetle to newly eclosed females resulted in up to a 5‐fold increase in fat body Vg mRNA levels compared to acetone‐treated control females. However, none of these increases were statistically significant. We also measured hemolymph Vg in females subjected to prolonged treatment with an intermediate dose of 300 μg of methoprene/g beetle and found no statistically significant increase in hemolymph Vg following treatment. There was, however, a significantly positive correlation between Vg mRNA and hemolymph Vg. Conversely, although injecting sexually mature females with fluvastatin (an inhibitor of JH biosynthesis in the corpora allata) at a dose of 40 μg/ beetle resulted in significantly decreased JH titers in treated females compared to saline‐injected controls, Vg transcription rates were not affected. We suggest that in burying beetles, JH alone is not sufficient to upregulate the expression of the Vg genes and that other factors may be involved in regulating their vitellogenic cycle as well. Arch. Insect Biochem. Physiol. 63:82–91, 2006. © 2006 Wiley‐Liss, Inc.
Synchrotron radiation small angle scattering studies of thermal stability of xylanase XYNII from Trichoderma longibrachiatum
Authors: Kozak Maciej
Published: September 2006

Xylanase XYNII from Trichoderma longibrachiatum is a small protein of the molecular weight 21 kDa, belonging to the family 11 of glycosyl hydrolases, which catalyses hydrolysis of xylan. This article reports thermal stability study of xylanase XYN II conformation in the temperature range 15–65°C by the small angle synchrotron radiation scattering. The study has been performed at different pH conditions: at pH 4.0 (below the physiological optimum of the enzyme activity) at pH 5.8 close to the optimum for enzymatic activity and at pH 8.0. The radius of gyration and the pair distance distribution function p(r) have been analyzed to characterize the changes of the enzyme conformation on heating. In the environment of the pH close to that of the optimum for the enzymatic activity, xylanase shows the greatest thermal stability and undergoes denaturation only above 55°C. In the acidic and basic environments, the enzyme stability is much lower and denaturation begins at 45°C. On the basis of the SAXS data, the shape of the xylanase molecule in solution in different temperatures has been reconstructed using ab initio method and program DAMMIN. The shape of the xylanase molecule at room temperature is similar to the right hand, which is typically observed for xylanase crystal structure. In higher temperatures (close to the enzyme activity optimum), the conformation of the right hand is loosened and half opened. © 2006 Wiley Periodicals, Inc. Biopolymers 83: 668–674, 2006

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
Comparison of several Nicotiana species as hosts for high‐scale Agrobacterium‐mediated transient expression
Authors: Sheludko Y.V. , Sindarovska Y.R. , Gerasymenko I.M. , Bannikova M.A. , Kuchuk N.V.
Published: September 2006

Agrobacterium‐mediated transient expression may be regarded as a promising method for inexpensive large‐scale production of recombinant proteins. We optimized the protocol of transient expression in Nicotiana benthamiana and compared six Australian species of Nicotiana as hosts for transient expression. The transient expression of GFP under 35S CaMV promoter was observed in all species tested, although the GFP content in leaves of N. benthamiana, N. exigua, and N. excelsior was significantly higher (3.8, 3.7, and 2.0% TSP, respectively). Usage of viral‐based expression system resulted in considerable increase of GFP accumulation in N. excelsior and N. benthamiana (63.5 and 16.2% TSP, respectively). We displayed that N. excelsior has the best characteristics in regard to biomass yield as well as GFP accumulation level for both types of the expression cassettes tested. Biotechnol. Bioeng. 2007;96: 608–614. © 2006 Wiley Periodicals, Inc.
Effect of caffeic acid phenethyl ester on treatment of experimentally induced methicillin‐resi̇stant Staphylococcus epidermidis endophthalmitis in a rabbit model
Authors: Yıldırım Özlem , Yılmaz Ayça , Öz Özay , Vatansever Halil , Cinel Leyla , Aslan Gönül , Tamer Lülüfer , Adıgüzel Ufuk , Arpacı Rabia , Kanık Arzu , Emekdaş Gürol
Published: September 2006

This study investigated the anti‐inflammatory effects of caffeic acid phenethyl ester (CAPE), a natural bee‐produced compound, and compared it with corticosteroids in the treatment of experimentally induced methicillin‐resistant Staphylococcus epidermidis (MRSE) endophthalmitis in addition to intravitreal antibiotics. An experimental endophthalmitis model was produced in 24 New Zealand albino rabbits by unilateral intravitreal injection of 0.1 ml of 4.7 × 104 colony‐forming units (CFU) methicillin‐resistant S. epidermidis. The animals were then divided randomly into three treatment groups and a control group, group 1 (six rabbits), received only intravitreal vancomycin (1.0 mg/0.1 ml); group 2 (six rabbits), received both intravitreal vancomycin (1.0 mg/0.1 ml) and intravitreal dexamethasone (400 µg/0.1 ml) and group 3 (six rabbits), received both intravitreal vancomycin (1.0 mg/0.1 ml) and subtenon CAPE (10 mg/0.3 ml) after 24 h post‐infection. No treatment was given to the control group. Treatment efficacy was assessed by clinical examination, vitreous culture and histopathology. There were no statististically significant differences between clinical scores of all groups in examinations at 24 and 48 h post‐infection (p = 0.915 and p = 0.067 respectively), but in examinations at 72 h post‐infection and after 7 days post‐infection, although the clinical scores of treatment groups were not significantly different from each other, they were significantly lower than the control group (p < 0.05). The culture results of all groups were sterile. As a result, CAPE was found to be as effective as dexamethasone in reducing inflammation in the treatment of experimental MRSE endophthalmitis when used with antibiotics. More studies are needed to determine the optimal administration route and effective dosage of this compound. Copyright © 2006 John Wiley & Sons, Ltd.
Reversal of Regioselectivity and Enhancement of Rates of Nitrile Oxide Cycloadditions through Transient Attachment of Dipolarophiles to Cyclodextrins
Authors: Barr Lorna , Lincoln Stephen F. , Easton Christopher J.
Published: September 2006

The reactions of nitrile oxides with monosubstituted dipolarophiles, such as propiolamide, typically afford proportionally 80 % or more of the 3,5‐disubstituted cycloadducts. By contrast, the reactions of 6A‐deoxy‐6A‐propynamido‐β‐cyclodextrin with 4‐tert‐butylbenzonitrile oxide and 4‐phenylbenzonitrile oxide afford >90 % and approximately 85 % of the corresponding 3,4‐disubstituted isoxazoles, respectively. As well as reversing the regioselectivity, the cyclodextrin increases the rates of these cycloadditions. The extent of the acceleration is up to more than three orders of magnitude for the production of the cycloadduct preferred by the cyclodextrin, but even the rate of reaction to give the less favored regioisomer is increased. With 6A‐deoxy‐6A‐propynamido‐β‐cyclodextrin, the cycloadducts are not easily separated from the cyclodextrin, as the amide bond is not readily cleaved. In comparison, the regioselectivity of the cycloadditions of 4‐tert‐butylbenzonitrile oxide with acrylic acid, methacrylic acid, and crotonic acid is also altered by formation of the corresponding cyclodextrin esters, by factors of 500, >10, and >100, respectively. The rates of cycloaddition are also increased by up to 475 times, and in these cases the products of cycloaddition are readily released from the cyclodextrin through ester hydrolysis. Incorporating these processes into a reaction cycle, acylation of β‐cyclodextrin with p‐nitrophenyl acrylate and subsequent treatment first with 4‐tert‐butylbenzonitrile oxide and then with base, the latter to catalyze ester hydrolysis and regenerate the β‐cyclodextrin, affords proportionally fivefold more of the 3,4‐disubstituted isoxazoline than is produced directly from acrylic acid.
The Solution Structure of Stilbenoid Dendrimers: A Small‐Angle Scattering Study
Authors: Rosenfeldt Sabine , Karpuk Elena , Lehmann Matthias , Meier Herbert , Lindner Peter , Harnau Ludger , Ballauff Matthias
Published: September 2006

The spatial structure of a stilbenoid dendrimer is investigated by small‐angle X‐ray scattering (SAXS) and small‐angle neutron scattering (SANS) in dilute solution. All measurements are performed in toluene. The dendrimer consists of a stilbenoid scaffold with appended hexyloxy chains. SAXS is mainly sensitive to the dendrimer scaffold whereas SANS intensity, measured in fully deuterated toluene, derives from the solute molecules. The resulting SAXS and SANS intensities are analyzed by comparison with various models. It is found that the model of a circular disk gives the best description of the data. SAXS data demonstrate that the stilbenoid scaffold is flat as expected for benzene rings conjugated through vinylene units. Thus, it can be described by a circular disk with a radius of 1.6 nm and a thickness of 0.7 nm. SANS, on the other hand, shows that the hexyloxy chains are not confined in the plane defined by the core. This is derived from modeling the SANS data with a much thicker circular disk (radius: 2.4 nm, thickness: 1.8 nm). The structure factor S(q), describing the interaction of the dendrimers at higher concentrations, is modeled quantitatively with the “polymer reference interaction site model” (PRISM) integral equation formalism for hard plates such as particles. Here the structural data obtained from the analysis of the SANS data are used so that no new adjustable parameter is necessary for this description.
Efficient Delaunay‐based localized routing for wireless sensor networks
Authors: Wang Yu , Li Xiang‐Yang
Published: September 2006

Consider a wireless sensor network consisting ofnwireless sensors randomly distributed in a two‐dimensional plane. In this paper, we show thatwith high probabilitywe can locally find a path for any pair of sensors such that the length of the path is no more than a constant factor of the minimum. By assuming each sensor knows its position, our new routing method decides where to forward the message purely based on the position of current node, its neighbours, and the positions of the source and the target. Our method is based on a novel structure called localized Delaunay triangulation and a geometric routing method that guarantees that the distance travelled by the packets is no more than a small constant factor of the minimum when the Delaunay triangulation of sensor nodes are known. Our experiments show that the delivery rates of existing localized routing protocols are increased when localized Delaunay triangulation is used instead of several previously proposed topologies, and our localized routing protocol based on Delaunay triangulation works well in practice. We also conducted extensive simulations of another localized routing protocol,face routing. The path found by this protocol is also reasonably good compared with previous one although it cannot guarantee a constant approximation on the length of the path travelled theoretically. Copyright © 2006 John Wiley & Sons, Ltd.
Energy optimization for chain‐based data gathering in wireless sensor networks
Authors: Yen Li‐Hsing , Cai Ming‐Zhou , Cheng Yang‐Min , Yang Ping‐Yuan
Published: September 2006

This paper aims to minimize energy expense for chain‐based data gathering schemes, which is essential to prolong the operation lifetime of wireless sensor networks. Energy expense in chain‐based data gathering schemes consists of two parts. One corresponds to inter‐sensor communications and depends on chain structure. The other corresponds to leader‐BS (base station) communications and depends on leader scheduling policy. To optimize inter‐sensor communications, the notion of virtual chain is utilized, where an edge may correspond to a multi‐hop data propagation path to conserve power. In contrast, an edge in previous work can only be a costly direct communication link. To optimize leader‐BS communications, a leader scheduling rule is presented, where the node with the maximum residual power will be selected to be the leader of the chain. In contrast, nodes in previous work act as leaders by turns, resulting in non‐uniform energy consumption among sensors. Simulation results show that our strategies are nearly optimal in terms of power conservation. Copyright © 2006 John Wiley & Sons, Ltd.
Integration of mobility and intrusion detection for wirelessad hocnetworks
Authors: Sun Bo , Wu Kui , Xiao Yang , Wang Ruhai
Published: September 2006

One of the main challenges in building intrusion detection systems (IDSs) for mobilead hocnetworks (MANETs) is to integrate mobility impacts and to adjust the behaviour of IDSs correspondingly. In this paper, we first introduce two different approaches, a Markov chain‐based approach and a Hotelling'sT2test based approach, to construct local IDSs for MANETs. We then demonstrate that nodes' moving speed, a commonly used parameter in tuning IDS performances, is not an effective metric to tune IDS performances under different mobility models. To solve this problem, we further propose anadaptivescheme, in which suitable normal profiles and corresponding proper thresholds can be selectedadaptivelyby each local IDS through periodically measuring its locallink change rate, a proposed unified performance metric. We study the proposed adaptive mechanism at different mobility levels, using different mobility models such as random waypoint model, random drunken model, and obstacle mobility model. Simulation results show that our proposed adaptive scheme is less dependent on the underlying mobility models and can further reduce false positive ratio. Copyright © 2006 John Wiley & Sons, Ltd.
Alk‐2‐ynyl Trimethylsilyl Chalcogenoethers by Nucleophilic Substitution of Propargyl Bromides
Authors: Taher Deeb , Wallbank Andrew I. , Turner Elizabeth A. , Cuthbert Heather L. , Corrigan John F.
Published: September 2006

Lithium (trimethylsilyl)chalcogenolates have been generated and used to prepare a series of alk‐2‐ynyl trimethylsilyl chalcogenoethers from the corresponding propargyl bromides in good yield. The thermal decomposition of the telluroethers has also been studied. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Stereoselective Synthesis of β‐Amino Ketones via Direct Mannich‐Type Reactions, Catalyzed with ZrOCl2·8H2O under Solvent‐Free Conditions
Authors: Eftekhari‐Sis Bagher , Abdollahifar Amir , Hashemi Mohammed M. , Zirak Maryam
Published: September 2006

At room temperature, zirconium oxychloride (ZrOCl2·8H2O) efficiently catalyzes the direct Mannich‐type reaction of a variety of in situ generated aldimines using aldehydes and anilines with ketones in a three‐component reaction under solvent‐free conditions. The reaction proceeds rapidly and affords the corresponding β‐amino ketones in good to high yields with good to excellent stereoselectivities. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of Purines Bearing Functionalized C‐Substituents by the Conjugate Addition of Nucleophiles to 6‐Vinylpurines and 6‐Ethynylpurines
Authors: Kuchař Martin , Pohl Radek , Votruba Ivan , Hocek Michal
Published: September 2006

Purines bearing diverse β‐substituted ethyl or vinyl groups in position 6 were prepared by the conjugate addition of N‐, O‐ and S‐nucleophiles to 6‐vinylpurines or 6‐ethynylpurines. The scope of this methodology was systematically studied. The addition of amines, alcoholates and thiolates to 6‐vinylpurines gave the corresponsing 6‐(2‐aminoethyl)‐, 6‐(2‐alkoxyethyl)‐ and 6‐[2‐(alkylsulfanyl)ethyl]purines. The addition of amines to 6‐ethynylpurines gave 6‐(2‐aminovinyl)purines, while the addition of alcoholates and thiolates gave 6‐(2‐dialkoxyethyl)‐ and 6‐[2‐bis(alkylsulfanyl)ethyl]purines. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Short and Efficient Diastereoselective Synthesis of Enantiopure 1‐Substituted 1H‐2‐Benzopyrans
Authors: Pedrosa Rafael , Sayalero Sonia , Vicente Martina
Published: September 2006

The reaction of homophthaldehyde with (–)‐8‐(benzylamino)menthol is regio‐ and diastereo‐selective, leading to the chiral perhydro‐1,3‐benzoxazine 3 as a single diastereoisomer. The addition of different organometallics to 3 yielded alcohols 4 in excellent yields. Hydrolysis of carbinols, with 2 % HCl in methanol or ethanol, allowed for the synthesis of 1,3‐disubstituted isochromanes, but hydrolysis in toluene led to enantiopure 1‐substituted isochromenes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Restoring identity through outgroup helping: beliefs about international aid in response to the December 2004 tsunami
Authors: van Leeuwen Esther
Published: September 2006

In this paper, the December 2004 tsunami tragedy was used as a background to investigate beliefs about intergroup helping. The general aim of the research was to test the proposal that helping can be used to reaffirm a threatened social identity. Two experiments conducted with Dutch participants (N = 78 and N = 73) tested the hypothesis that a threatened Dutch national identity would result in stronger preferences for help to the victims of the tsunami, but only in a domain that is positively and distinctly related to that national identity (i.e. water management). Results from both studies confirmed this hypothesis. Study 2 also showed a reversal of this effect in a domain negatively related to that identity. Moreover, perceived identity threat in Study 2 reduced over time in the high threat condition but not in the low threat condition, and this reduction was positively associated with the endorsement of water management help. Also, as predicted, in both studies a threatened national identity resulted in stronger beliefs that Dutch relief organisations should stay in control over their aid. Copyright © 2006 John Wiley & Sons, Ltd.
Quantitative‐competitive polymerase chain reaction coupled with slab gel and capillary electrophoresis for the detection of roundup ready soybean and maize
Authors: Dinelli Giovanni , Bonetti Alessandra , Marotti Ilaria , Minelli Maurizio , Navarrete‐Casas Miguel , Segura‐Carretero Antonio , Fernández‐Gutiérrez Alberto
Published: September 2006

The aim of the present study was to develop a quantitative‐competitive PCR (QC‐PCR) method to detect DNA from transgenic herbicide‐resistant (roundup ready, RR) soybean and maize. Since no QC‐PCR system for the quantification of RR maize had been published at the time of writing, a specific competitor DNA for transgenic event was developed. For the QC‐PCR of RR‐soybean, a commercially available competitor was employed. These internal standards were calibrated by coamplifying with mixtures containing RR‐soybean and maize DNAs. The calibrated QC‐PCR systems were applied to certified RR‐soybean and maize flour mixtures in order to demonstrate their suitability not only for the quantification of the glyphosate resistance traits in DNA matrices, but also in practically relevant samples. In addition, a special focus of the present work was to compare the detection of QC‐PCR products by slab gel and CGE with UV detection. CGE permitted the precise detection of transgenic events also below the equivalence points; while in slab gel electrophoresis, due to the low sensitivity the quantification of genetically modified DNA was allowed only at the equivalence point.
Sensitive determination of carbohydrates labelled with p‐nitroaniline by capillary electrophoresis with photometric detection using a 406 nm light‐emitting diode
Authors: Momenbeik Fariborz , Johns Cameron , Breadmore Michael C. , Hilder Emily F. , Macka Miroslav , Haddad Paul R.
Published: September 2006

p‐Nitroaniline was explored as a derivatising reagent for UV absorbance detection of carbohydrates after separation by CE. This derivatising agent has three advantages: first, it has excellent water solubility; second, it has high molar absorptivity; and third, it is possible to obtain sensitive detection using a UV or blue light‐emitting diode (LED) as the light source. The labelling reaction took less than 30 min to complete with high reaction yield. The separation process was modelled and optimised using an artificial neural network. Nine carbohydrates were separated by a CE system within 16 min using a 0.17 M boric acid buffer at pH 9.7. On‐column LED detection at 406 nm allowed the detection of carbohydrates with good detection limits (<1.1 µM or 8.8 fmol) and reproducible quantification in the concentration range of 2.6–200 µM. This method was applied successfully to the determination of component carbohydrates in some food samples.
Adaptive contrast enhancement of two‐dimensional electrophoretic protein gel images facilitates visualization, orientation and alignment
Authors: Van Belle Werner , Sjøholt Gry , Ånensen Nina , Høgda Kjell‐Arild , Gjertsen Bjørn Tore
Published: September 2006

2‐DE is a powerful technique to discriminate post‐translationally modified protein isoforms. However, all steps of 2‐DE preparation and gel‐staining may introduce unwanted artefacts, including inconsistent variation of background intensity over the entire 2‐DE gel image. Background intensity variations limit the accuracy of gel orientation, overlay alignment and spot detection methods. We present a compact and efficient denoising algorithm that adaptively enhances the image contrast and then, through thresholding and median filtering, removes the gray‐scale range covering the background. Applicability of the algorithm is demonstrated on immunoblots, isotope‐labeled gels, and protein‐stained gels. Validation is performed in contexts of (i) automatic gel orientation based on Hough transformation, (ii) overlay alignment based on cross correlation and (iii) spot detection. In gel stains with low background variability, e.g. Sypro Ruby, denoising will lower the spot detection sensitivity. In gel regions with high background levels denoising enhances spot detection. We propose that the denoising algorithm prepares images with high background for further automatic analysis, without requiring manual input on a gel‐to‐gel basis.
Agarose isoelectric focusing can improve resolution of membrane proteins in the two‐dimensional electrophoresis of bacterial proteins
Authors: Altenhofer Pia , Schierhorn Angelika , Fricke Beate
Published: September 2006

2‐D separation of bacterial membrane proteins is still difficult despite using high‐resolution IPG‐IEF/SDS‐PAGE. We were searching for alternative methods to avoid typical problems such as precipitation, low solubility, and aggregation of membrane proteins in the 1‐D separation with IPG‐IEF. Blue native electrophoresis (BNE) and agarose IEF (A‐IEF) were tested for their separation capacity and their capability of replacing IPG‐IEF in the first dimension. SDS‐PAGE was chosen for the second dimension on account of its outstanding resolution. We could confirm that only A‐IEF was a useful replacement for the IPG‐IEF in the first dimension resulting in 2‐D protein distributions with additional membrane protein spots not being found after IPG‐IEF/SDS‐PAGE. A second interesting result was that the agarose IEF mediates the possibility of separation of membrane proteins in a partially native state in the first dimension. This native A‐IEF resulted in drastically changed spot patterns with an acidic shift of nearly all spots and divergent distribution of proteins compared to non‐native A‐IEF and IPG‐IEF. We found out that native and non‐native A‐IEF are powerful tools to supplement IPG‐IEF/SDS‐PAGE.
Capillary electrophoresis of liposomes functionalized for protein binding
Authors: Bilek Gerhard , Kremser Leopold , Blaas Dieter , Kenndler Ernst
Published: September 2006

CE enabled assessing the attachment of hexa‐histidine‐tagged proteins to functionalized phospholipid liposomes. The liposomes were made of 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine, phosphatidyl‐ethanolamine, cholesterol and distearoyl‐glycero‐3‐phosphoethanolamine‐N‐methoxy(polyethylene glycol) in a molar ratio of 29:26:40:5. The unilamellar vesicles, which had an average diameter of 170 nm, were labelled by inclusion of FITC‐dextran for fluorescence detection. CE was carried out in poly(vinyl alcohol) (PVA)‐coated capillaries at 25°C with a BGE consisting of Tris‐HCl (50 mM, pH 8.0). For conjugation of the liposomes with the proteins (soluble synthetic receptor fragments with molecular mass of 60 and 70 kDa, respectively), Ni2+ was implanted into the vesicle surface by an anchor lipid containing a nitrilotriacetate acid (NTA) group as complexation agent for the metal ions. The difference in surface charge enabled the separation of the different species of interest by CE: plain vesicles, vesicles functionalised with Ni‐NTA, vesicle–protein complexes and the species formed upon removal of the Ni‐ions by complexation with EDTA. Loss of the Ni‐ions resulted in the release of the proteins and the reappearance of the plain Ni‐free NTA‐liposome species in the electropherograms.
An integrated micropump and electrospray emitter system based on porous silica monoliths
Authors: Wang Ping , Chen Zilin , Chang Hsueh‐Chia
Published: September 2006

The work presents the design of an integrated system consisting of a high‐pressure electroosmotic (EO) micropump and a microporous monolithic emitter, which together generate a stable and robust electrospray. Both the micropump and electrospray emitter are fabricated using a sol–gel process. Upon application of an electric potential of sufficient amplitude (>2 kV), the pump delivers fluids with an electroosmotically induced high pressure (>1 atm). The same potential is also harnessed to electrostatically generate a stable electrospray at the porous emitter. Electrokinetic coupling between pump and spray produces spray features different from sprays pressurized by independent mechanical pumps. Four typical spray modes, each with different drop sizes and charge‐to‐mass ratios, are observed and have been characterized. Since the monolith is silica‐based, this integrated device can be used for a variety of fluids, especially organic solvents, without the swelling and shrinking problems that are commonly encountered for polymer monoliths. The maximum pressure generated by a 100 µm id monolithic pump is ˜3 atm at an applied voltage of 5 kV. The flow rate can be adjusted in the range of 100 nL/min to 1 µL/min by changing the voltage. For a given applied voltage across the pump and emitter system, it is seen that there exists one unique flow rate for which flow balance is achieved between the delivery of liquid to the emitter by the pump and the liquid ejection from the emitter. Under such a condition, a stable Taylor cone is obtained. The principles that lead to these results are also discussed.
Electrochromatographic behavior of silica monolithic capillaries of different skeleton sizes synthesized with a simplified and shortened sol–gel procedure
Authors: Puy Guillaume , Demesmay Claire , Rocca Jean‐Louis , Iapichella Julien , Galarneau Anne , Brunel Daniel
Published: September 2006

Silica monolithic capillaries (SMCs) were synthesized by a sol–gel process. First, a simplification of the synthesis was proposed by replacing the calcination and the drying steps which can have tremendous effects on chromatographic and physical properties, by a single water or methanol 2 h washing step. The efficiency of such a washing step was demonstrated and the comparison of the chromatographic and electrochromatographic properties between calcined and washed SMCs has shown that such a modification did not impair retention, efficiency, and stability of the monolith. This simplified procedure was carried out to synthesize SMCs with two different skeleton sizes. These capillaries were evaluated in electrochromatography and present high efficiencies (H = 5 µm) at least equal to the best ones reported in the literature. Furthermore, the influence of the skeleton size on the EOF of the second kind (EOF‐2) was investigated with unmodified SMCs used under various experimental conditions including electrical field strength and buffer concentration. The ionic strength of the mobile phase and the applied electrical field that enable this EOF‐2 were related to the size of the skeleton which was tuned by the synthesis conditions.
A self‐contained polymeric 2‐DE chip system for rapid and easy analysis
Authors: Usui Keisuke , Hiratsuka Atsunori , Shiseki Kisho , Maruo Yuji , Matsushima Toshiyuki , Takahashi Katsuyoshi , Unuma Yutaka , Sakairi Koji , Namatame Ichiji , Ogawa Yasuhiro , Yokoyama Kenji
Published: September 2006

We developed a polymeric 2‐DE chip system. The chip consisted of an IEF region, an SDS‐PAGE region, a valveless connection port, and a sample introduction port. A “junction structure” as a valveless connection port, which allowed separating and connecting the first‐ and second‐dimensional gels, was fabricated between their regions. A “solution inlet” as a sample introduction port was fabricated to perform the liquid and sample introductions without solution leakage. Simultaneous sample monitoring was performed using the on‐chip detection system. The performances of the system were demonstrated using commercially available proteins as a standard specimen and tissue‐extracted proteins as the real samples. All procedures were employed without any movement of relocation part. This new 2‐D separation system realized improved labor‐intensive operations and a reduced experimental time.
Carbon nanotube‐enhanced separation of DNA fragments by a portable capillary electrophoresis system with contactless conductivity detection
Authors: Xu Yan , Li Sam Fong Yau
Published: September 2006

It was demonstrated that separation of DNA fragments by a CE‐contactless conductivity detection system (CE‐CCD) could be enhanced with multiple‐wall carbon nanotubes (MWCNs) as buffer additive. For HaeIII digest of ΦX174 DNA, optimized MWCN concentration was obtained when the MWCN was above its threshold concentration, at which MWCN could form a network in the buffer as pseudostationary phase to provide additional interaction sites. In the case of larger DNA, MWCN near or below its threshold concentration was enough to provide great improvement of the resolution, which was shown by the separation of the 2‐Log DNA ladder. Furthermore, the buffer containing MWCN could provide a more stable baseline in the CE‐CCD system, owing to less fluctuation of its conductivity. Compared with CE‐UV, CE‐CCD with MWCN could provide lower LODs as well as better resolution.
Improved estimation for temporally clustered extremes
Authors: Fawcett Lee , Walshaw David
Published: September 2006

In this paper, we investigate the effects ofdeclusteringapplied to sequences of extreme observations. Through a simulation study, we demonstrate that the common practice of analysingpeaks over thresholds(POT) is liable to incur serious bias in the estimation of parameters, as well as thereturn levelsused as design specifications when building to withstand extremes of wind or rain, or river or sea level. We demonstrate that a much simpler approach, the direct analysis ofallexceedances of a high threshold, can reduce this bias to negligible levels. This approach has, until now, been unpopular, because the data being analysed are not independent. The effect of this is to cause the standard errors associated with parameter estimates to underestimate the uncertainty attached to these estimates. We employ existing but little‐used methodology to inflate these standard errors, and we demonstrate that the adjusted values are very good representations of the true uncertainty associated with maximum likelihood estimates. The overall approach has thus achieved the effect of eliminating the bias in estimation, while accounting for any undesirable effects caused by dependent data.

We apply our approach to a sequence of sea‐surge data from southwest England, and illustrate the discrepancies between this and a POT approach, which are consistent with the POT approach underestimating long‐period return levels. We also pay considerable attention to checking the robustness of our results, demonstrating that the problems of bias caused by the POT approach apply systematically over all of the declustering schemes we consider, as well as over the entire range of tail behaviours. When the primary interest is in return‐level estimation, we recommend that our procedure will generally prove to be much more effective and reliable than the POT approach. Should there be a deeper interest in the serial dependence itself, then we recommend that this dependence is explicitlymodelled, and we refer the reader to an earlier paper by the authors, published in this journal. Copyright © 2006 John Wiley & Sons, Ltd.
Fire losses in selected property classifications of non‐residential, commercial and residential wood buildings. Part 1: hotels/motels and care homes for aged
Authors: Richardson Leslie R.
Published: September 2006

In an attempt to evaluate the adequacy of building code requirements for selected classifications of non‐residential, commercial and residential wood buildings, researchers at Forintek Canada Corp. have examined Canadian and American fire loss statistics and compared fire losses for the selected classifications of wood buildings with those for similar buildings of non‐combustible construction. They have also examined causal factors associated with fires in those structures, extent of flame and smoke spread, ability of sprinkler systems and building construction to minimize fire losses, and outcomes of fire events. Because of the volume of information that was analysed, the results are being reported through three separate papers. This, the first, presents the ‘big picture’ with respect to fire losses in the selected classifications of non‐residential, commercial and residential structures, and discusses in detail fire losses for hotel/motel properties and care homes for the aged. Copyright © 2006 John Wiley & Sons, Ltd.
The feasibility of a GP led screening intervention for depression among nursing home residents
Authors: Davidson Sandra , Koritsas Stella , O'Connnor Daniel W. , Clarke David
Published: September 2006

Aim

To examine the feasibility of a brief intervention training general practitioners (GPs) in the administration of a depression screening instrument for use among nursing home residents.

Intervention

GPs attended a single education session on late‐life depression and were trained in the use of the Cornell Scale for Depression in Dementia. Following the intervention GPs reviewed their patients for depression.

Outcome measures

Diagnosis of depression pre and post intervention; changes in antidepressant medications post intervention.

Results

Ten GPs and 38 patients completed all components of the study. GPs identified that 24% of their patients had Cornell Scores indicative of probable major depression that was either unrecognised or inadequately treated. 88% of these patients had been previously diagnosed with depression. A further 32% of patients exhibited depression symptoms, half (50%) of whom had a previous diagnosis of depression. Reviewing patients had an effect on antidepressant prescribing for patients with probable major depression, with GPs making changes to the antidepressant medication of 29% of patients.

Conclusions

The high rate of residents presenting with probable major depression despite being prescribed antidepressants indicate that depression symptoms are inadequately recognised and treated in nursing homes. This study demonstrated that a single education session on late‐life depression was feasible and was associated with an improvement in GPs' recognition of depression among nursing home patients. Copyright © 2006 John Wiley & Sons, Ltd.
Sandwich compounds with central hypercoordinate carbon, nitrogen, and oxygen: A quantum‐chemical study
Authors: Minyaev Ruslan M. , Minkin Vladimir I. , Gribanova Tatyana N. , Starikov Andrey G.
Published: September 2006

Ab initio (MP2(fu)/6‐311+G**) and DFT (B3LYP/6‐311+G**) calculations predict stable structures of sandwich compounds with the central carbon, nitrogen, and oxygen atoms surrounding lithium counterions between three‐membered (BH)3rings. The lithium counterions play a crucial role in the stabilization of these systems. The topological Bader analysis performed for these sandwich systems demonstrates that the central atom is linked to the ligands by nine‐bond paths and, consequently, should be regarded as a nine‐coordinated atom. Such a coordination number of carbon is the highest for all known main group organoelement compounds. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:464–474, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20268
Organotins‐promoted peroxidation of unsaturated fatty acids: A new antioxidative scavenger for promoters
Authors: Milaeva Elena R. , Tyurin Vladimir Yu. , Shpakovsky Dmitry B. , Gerasimova Olga A. , Jingwei Zhang , Gracheva Yulia A.
Published: September 2006

The organotin compounds RnSnX4‐n are promoters of lipids peroxidation. The influence of (CH3)2SnCl2, (C2H5)2SnCl2, and SnCl2 upon the radical chain oxidation of oleic acid as model substrate R′H for lipid peroxidation in the simultaneous presence of porphyrins (free bases of meso‐tetrakis(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)porphyrin (R″4PH2) and of meso‐tetraphenylporphyrin (TPPH2)) has been studied. The monitoring of the unsaturated acid peroxidation level has been performed by the determination of the total concentration of isomeric hydroperoxides as well as of the thiobarbituric acid reactive substances, as markers of carbonyl compounds formation following the hydroperoxides decomposition. The organotin compounds demonstrate prooxidative activity. The promoting effect of these compounds decreases in the presence of TPPH2. The free‐base porphyrin R″4PH2, containing the antioxidative phenolic moieties (2,6‐di‐tert‐butylphenol), demonstrates the acute inhibitory effect upon the acid's peroxidation. The analogous results have been achieved when compared with the influence of CH3HgI and HgCl2 upon the acids peroxidation of oleic acid in the presence of porphyrins. This fact points out that meso‐tetrakis(3,5‐di‐tert‐butyl‐4‐hydroxyphenyl)porphyrin shows the activities of both the antioxidant and of the scavenger for metals and might be used as a new antioxidative scavenger preventing lipids peroxidation. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:475–480, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20269
The Reaction of 3,6‐di‐tert‐butyl‐o‐benzoquinone with tin amalgam: Synthesis and structure of tin catecholato complexes
Authors: Piskunov Alexandr V. , Lado Aryna V. , Fukin Georgy K. , Baranov Evgeny V. , Abakumova Ludmila G. , Cherkasov Vladimir K. , Abakumov Gleb A.
Published: September 2006

The reduction of 3,6‐di‐tert‐butyl‐o‐benzoquinone with tin amalgam gives the different tin catecholate complexes. The use of polar solvents for this reaction leads to the formation of Cat2Sn · L2 species (where Cat—dianion of 3,6‐di‐tert‐butylcatechol, L = Et2O, THF, Py). The reaction carried out in toluene produces the mixture of dicatecholate tin(IV) and catecholate tin(II) derivatives. The complex Cat2Sn · (Et2O)2 was shown to be a good starting reagent for the preparation of different tin(IV) catecholate complexes of the type Cat2Sn ·  L′ (L′ = 1,2‐dimethoxyethane, 1,4‐di‐tert‐butyldiazadiene‐1,3, o‐phenantrolyne, α,α′‐dipyridyl) using ligand exchange reactions. Compounds Cat2Sn · (Et2O)2, Cat2Sn · (THF)2, Cat2Sn · (ButNCHCHNBut), and (CatSn)3 have been crystallographically characterized. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:481–490, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20271
Phosphonoallenes for building organophosphorus derivatives
Authors: Brel Valery K.
Published: September 2006

This review article deals with new approaches to polyfunctional phosphonoallenes as well as synthetically useful reactions of this class of organophosphorus compounds for design of various heterocyclic phosphonates, new phosphonolipids, and phosphononucleotides. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:547–556, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20275
The synthesis and reactions of betaines formed in reactions of tertiary phosphines with unsaturated carboxylic acids and their derivatives
Authors: Galkin V. I. , Bakhtiyarova Yu. V. , Sagdieva R. I. , Galkina I. V. , Cherkasov R. A.
Published: September 2006

On the basis of our systematic investigations, the main trends concerning synthesis, structure, and reactivity of carboxylate phosphabetaines—phosphorus analogs of organic aminoacids—are considered and analyzed. A wide series of phosphabetaines has been obtained in reactions of tertiary phosphines with unsaturated mono‐ and dicarboxylic acids, and also with their derivatives—esters and amides. By a plethora of experimental and theoretical methods, it has been shown that the thermodynamic stability of carboxylate phosphabetaines essentially depends on the structure of the initial phosphine and carboxylic acid. In some cases, the reaction between them is equilibrated. On the other hand, for a number of synthesized betaines, it is reliably established that these exist in equilibrium with isomeric phosphoranes. The extremely important condition for stabilization of phosphabetaine structures is the presence of proton‐donating reagents, which are included in their crystal lattice. In the series of symmetrically substituted derivatives, the interesting phenomenon of phosphorotropy of the phosphonium group is established. The reactivity of phosphabetaines in reactions with electrophilic reagents (haloid alkyls and acyls, isocyanates, corbodiimides) has been investigated. The majority of key structures have been confirmed by the direct X‐ray method. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:557–566, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20276
Solvent‐free alkali and alkaline earth metal complexes of di‐imine ligands
Authors: Fedushkin Igor L. , Chudakova Valentina A. , Skatova Aleksandra A. , Fukin Georgii K.
Published: September 2006

Compound [(dph‐BIAN)Mg(THF)]2(2) was prepared by reacting magnesium metal with 1,2‐ bis[(2‐biphenyl)imino]acenaphthene (dph‐BIAN) in THF, followed by crystallization from toluene. Reac‐ tion of CaI2 with (dpp‐BIAN)Li2 in toluene afforded [(dpp‐BIAN)Li]2Ca (3) (dpp‐BIAN = 1,2‐bis[(2,6‐diisopropylphenyl)imino]acenaphthene). Both complexes 2 and 3 were characterized by single crystal X‐ray diffraction. The 1H NMR spectroscopic data obtained for complex 3 in toluene solution indicated an agostic interaction between the methyl groups of the ligand and lithium atoms. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:663–670, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20277
Pentacoordinate organosilicon compounds— molecular structure and stereodynamic behavior of (trifluorosilylmethyl)succinimide and (trifluorosilylmethyl)glutarimide
Authors: Voronkov M. G. , Trofimova O. M. , Chernov N. F. , Bolgova Yu. I. , Albanov A. I. , Chipanina N. N. , Zelbst E. A.
Published: September 2006

The synthesis of pentacoordinate organosilicon compounds, N‐(trifluorosilylmethyl)succinimide (1) and N‐(trifluorosilylmethyl)glutarimide (2) is described. The X‐ray crystal analysis of compound 1 shows a slightly distorted trigonal‐bipyramidal coordination at silicon. Dynamic 19F, 13C, and 29Si NMR studies confirm the existence of an O → Si intramolecular hypervalent bond in solution. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:567–20278, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20278
Delivery of molecular versus particulate water in spontaneously breathing tracheotomized patients
Authors: Rozsasi Ajnacska , Dürr Jochen , Leiacker Richard , Keck Tilman
Published: September 2006

Background

Adequate humidification of inspired gas with active or passive humidifiers is a standard of care for tracheotomized patients. In this study, a comparison is made between the tracheal climate after tracheobronchial humidification either with molecular water (via a vaporizing humidifier) or particulate water (via spray) in spontaneously breathing tracheotomized patients.

Methods

We performed a randomized, 2‐way crossover study on 10 tracheotomized patients. Tracheal humidity and temperature were measured prior to and after use of a vaporizing humidifier and aerosol spray, respectively.

Results

After use of both the vaporizing humidifier and the aerosol spray, the end‐inspiratory total water content and water gradient in the upper trachea increased significantly, compared with baseline values before application. After end of use of the vaporizing humidifier, the total water content and the water gradient decreased significantly faster than after application of the aerosol spray.

Conclusions

Delivery of both molecular and particulate water significantly increases the tracheal climate and conditioning in the tracheal airways. Because the tracheal humidity remained on a higher level after aerosol spray, we speculate that particulate water may be efficient on tracheal humidification for longer. However, the positive effect on tracheal humidity after prolonged application of the aerosol spray remains to be proven. © 2006 Wiley Periodicals, Inc. Head Neck, 2006
Thyroid carcinoma associated with squamous cell carcinoma of the head and neck: Which policy?
Authors: Guzzo Marco , Quattrone Pasquale , Seregni Ettore , Bianchi Roberto , Mattavelli Franco
Published: September 2006

Background

Thyroid carcinoma occurring as a second primary associated with head and neck squamous cell carcinoma (HNSCC) is unusual. The clinical management of thyroid cancer in such cases has been debated.

Methods

Between 1975 and 2004, we collected 33 cases. The associated thyroid carcinoma was diagnosed either during or as a consequence of surgery planned as head and neck cancer treatment.

Results

The associated thyroid carcinoma was never seen to recur. Five‐year overall survival was 41%. Disease‐free survival after 40 and 66 months was 11.1% and 5.6%, respectively.

Conclusions

We consider the treatment of thyroid cancer to be complete when the thyroid gland, either with or without lymph nodes, has been included in the specimen obtained during surgery for HNSCC. In the group of cases in which associated thyroid carcinoma was only found within the neck lymph nodes and the thyroid gland has not been treated, we discourage further surgical treatment or radioactive iodine therapy. © 2006 Wiley Periodicals, Inc. Head Neck, 2006