bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of biodegradability of industrial wastewaters by chemical oxidation pre‐treatment
Authors: Mantzavinos Dionissios , Psillakis Elefteria
Published: April 2004

Chemical oxidation technologies are often employed for the treatment of complex industrial effluents that are not amenable to conventional biological methods. The role of chemical oxidation depends on the treatment objectives and may vary from partial remediation to complete mineralization. In the case of partial treatment, chemical oxidation aims at the selective removal of the more bioresistant fractions and their conversion to readily biodegradable intermediates that can subsequently be treated biologically. Coupling chemical pre‐oxidation with biological post‐treatment is conceptually beneficial as it can lead to increased overall treatment efficiencies compared with the efficiency of each individual stage. This paper reviews recent developments and highlights some important aspects that need to be addressed when considering such integrated schemes. Copyright © 2004 Society of Chemical Industry
Characterisation of the glass fraction of a selection of European coal fly ashes
Authors: Henry J , Towler MR , Stanton KT , Querol X , Moreno N
Published: April 2004

Fly ash largely consists of the inorganic content of coal that remains after combustion. The crystalline phases present in fly ash may form upon cooling of a molten alumino‐silicate glass. This view is supported by the spherical shape of many fly ash particles, inferring that they have gone through a viscous fluid state. The amorphous content in fly ash is believed to dominate reactivity behaviour, under both alkaline and acid conditions, because glasses have a higher potential energy than the equivalent crystal structure and the variation of bond angles and distances in a glass makes the bond breakage easier. It is the degradation behaviour under alkaline conditions, and the subsequent release of silica from the glass phase, that is important in the use of fly ash for conversion to zeolites and for pozzolanic applications in cement. This research comprehensively studies the composition, quantity and stability of the glass phase in a series of nine fly ashes sourced from Spanish and Italian power plants. The quantitative elemental composition of the glass phase in each fly ash was determined. Samples of the ashes then underwent a series of tests to determine the internal structure of the ash particles. Heat treatment of most of the ashes results in mullite crystallising from the glass phase; this is the crystalline phase that is predicated to form by both the relevant phase diagrams and also by NMR spectroscopy. In the ashes, mullite is present as a spherical shell, tracing the outline of the particle but in some specific cases the mullite skeleton is made up of coarse crystals reach also the internal parts of the particles. The morphology and density of the mullite crystals in these shells varies greatly. This work has supported the view that some crystalline phases present in fly ashes, such as mullite, form upon cooling of the amorphous glass melt as opposed to direct conversion from existing mineral phases in the coal during the combustion process. Copyright © 2004 Society of Chemical Industry
High resistance to aerial oxidation of an amorphous NiB/SiO2 catalyst: TP‐XRD, TPR and related investigations
Authors: Wang Yong‐Zhen , Li Xiang , Li He‐Xing , Wang Wei‐Jiang
Published: April 2004

An amorphous NiB/SiO2 catalyst, prepared by a reductive–impregnation method, was thoroughly studied as to its behavior in air and in benzene hydrogenation in a fixed‐bed reactor at atmospheric pressure. The results showed that the amorphous NiB/SiO2 catalyst possessed long life and excellent resistance to aerial oxidation. Even after calcination at 400 °C, TP‐XRD and TPR measurements revealed that the amorphous NiB/SiO2 catalyst was not oxidized, and could retain its activity in benzene hydrogenation. Copyright © 2004 Society of Chemical Industry
Development of an adenoviral vector system with adenovirus serotype 35 tropism; efficient transient gene transfer into primary malignant hematopoietic cells
Authors: Nilsson Marcus , Ljungberg Johan , Richter Johan , Kiefer Thomas , Magnusson Mattias , Lieber André , Widegren Bengt , Karlsson Stefan , Fan Xiaolong
Published: April 2004

Background

A paucity of coxsackie adenovirus receptor (CAR) hampers the adenovirus serotype 5 (Ad5)‐based vector‐mediated gene transfer into malignant hematopoietic cells. Fiber‐retargeted adenoviral vectors with species B tropism can potentially bypass the CAR requirement and facilitate efficient gene transfer into malignant hematopoietic cells.

Methods

For feasible generation of fiber‐retargeted adenoviral vectors, we have modified the versatile AdEasy system with a chimeric fiber gene encoding the Ad5 fiber tail domain and Ad35 fiber shaft and knob domains. An Ad5‐based vector encoding the green fluorescent protein (GFP) gene under the control of the PGK promoter with Ad35 fiber receptor specificity was generated (Ad5F35‐GFP). The Ad5F35‐GFP vector‐mediated gene transfer efficiency was compared with a fiber non‐modified Ad5‐GFP vector, which also encodes the GFP gene under the control of the PGK promoter.

Results

We demonstrated that a variety of Ad5‐refractory malignant myeloid and B lymphoid cell lines were highly permissive to the Ad5F35‐GFP vector infection. Importantly, primary chronic myeloid leukemic (CML) cells and chronic lymphocytic leukemia (CLL) B cells were superiorly transduced by the Ad5F35‐GFP vector at a multiplicity of infection (MOI) of 100 compared with the Ad5‐GFP vector.

Conclusions

Our study will facilitate the generation of fiber‐retargeted adenoviral vectors and enable transient genetic manipulation of primary malignant hematopoietic cells. Copyright © 2004 John Wiley & Sons, Ltd.
Short‐term culture of myeloid leukemic cells allows efficient transduction by adenoviral vectors
Authors: Vereecque Rodolphe , Saudemont Aurore , Quesnel Bruno
Published: April 2004

Background

Ex vivo gene therapy of acute myeloid leukemia (AML) requires efficient transduction of leukemic cells. Recombinant adenovirus has been reported to be a poorly efficient vector in leukemic cells. We investigated leukemic cell culture as a possible method of improving the efficacy of this vector.

Methods

Leukemic cell lines and primary cultured AML cells were incubated with adenoviral vectors carrying GFP, LacZ, or IL‐12 cDNA. Transduction efficiency was evaluated by measuring adenoviral genome copy number and transgene expression in leukemic cells. The expression of the coxsackie/adenovirus receptor (CAR), CD29, CD49e, and CD51/61 was measured, as was the effect of blocking integrin on adenoviral transduction.

Results

Increasing the multiplicity of infection (MOI) to 300 plaque‐forming units per cell enhanced transduction of leukemic cell lines and to a lesser degree of AML cells. Analysis of adenoviral genome copy per cell showed only a partial correlation between gene transfer efficiency and transgene expression. Culture of AML cells for 3 days prior to adenoviral transduction increased both adenoviral copy number per cell and the percentage of transgene‐expressing cells. CD29, CD49e, and CD51/61 but not CAR expression increased in cultured AML cells between days 0 and 3 and integrin‐blocking experiments showed inhibition of transduction in two of four AML samples tested.

Conclusions

Efficient ex vivo gene transfer in primary cultured AML cells can be achieved by short‐term culture of leukemic cells prior to gene transfer with adenoviral vectors at a high MOI. This effect appears to be at least partially mediated by enhanced integrin expression. Copyright © 2004 John Wiley & Sons, Ltd.
Lipid A components from Pseudomonas aeruginosa PAO1 (serotype O5) and mutant strains investigated by electrospray ionization ion‐trap mass spectrometry
Authors: Bedoux Gilles , Vallée‐Réhel Karine , Kooistra Oliver , Zähringer Ulrich , Haras Dominique
Published: April 2004

The lipid A components of the Pseudomonas aeruginosa strains PAO1 (wild‐type) and derived mutants PAO1 algC::tet and PAO1 PDO100 were isolated after mild acetic acid hydrolysis of LPS. Their structural heterogeneities were characterized using electrospray ionization (ESI) ion‐trap mass spectrometry (MS) with direct infusion in the negative ion mode without prior derivatization. The ESI‐mass spectra revealed monophosphorylated molecules corresponding to known tetra‐, penta‐ and hexaacylated structures of P. aeruginosa lipid A. The MS/MS fragmentation patterns allowed the location of fatty acyl chains on the disaccharide backbone of lipid A. In addition, a hexaacylated lipid A containing a hexadecanoyl chain was detected for the first time in strain P. aeruginosa PAO1. With multiple stages of fragmentation (MSn), the position of this hexadecanoyl chain O‐linked to the decanoyl chain at the C‐3′ position of the glucosamine backbone was determined. This sensitive method is suitable to reveal lipid A heterogeneity, i.e. the nature, number and distribution of acyl chains, without prior lipopolysaccharide purification. The lipid A from mutant strains were also characterized and significant differences were shown in the abundance of monophosphorylated lipid A components between the wild‐type and the mutant strains. Copyright © 2004 John Wiley & Sons, Ltd.
Structural analysis of lipid A from Escherichia coli O157:H7:K− using thin‐layer chromatography and ion‐trap mass spectrometry
Authors: Lee Chang‐Soo , Kim Yun‐Gon , Joo Hwang‐Soo , Kim Byung‐Gee
Published: April 2004

Rapid separation and structural identification of lipid A from Escherichia coli were performed using thin‐layer chromatography (TLC) and mass spectrometry (MS). After the resolved spot of the lipid A had been scraped from TLC plate, the sample was re‐extracted from the removed powder with chloroform–methanol (2 : 1, v/v) and analyzed by matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) and electrospray ionization (ESI) ion‐trap MS. For detailed structural characterization, multiple‐stage mass analysis (MS4) of the major species in ESI‐MS/MS provided important information about the series of fragment ions. The dominant fragment ions in each MS stage were produced from the loss of fatty acyl groups mainly driven by charge‐remote processes, and this information about the fragment ions can be used to deduce the composition or the position of the fatty acid substituent in the lipid A. In contrast, MALDI‐TOFMS indicated that fragmentation resulted from charge‐driven processes. Molecular mass profiling and fragmentation analysis provides essential information for clarifying the detailed structure of the lipid A from E. coli O157:H7:K−. Copyright © 2004 John Wiley & Sons, Ltd.
Bisphenol A causes hyperactivity in the rat concomitantly with impairment of tyrosine hydroxylase immunoreactivity
Authors: Ishido Masami , Masuo Yoshinori , Kunimoto Manabu , Oka Syuichi , Morita Masatoshi
Published: April 2004

We examined the effects of bisphenol A, an endocrine disruptor, on rat behavioral and cellular responses. Single intracisternal administration of bisphenol A (0.2‐20 μg) into 5‐day‐old male Wistar rats caused significant hyperactivity at 4–5 weeks of age. Rats were about 1.6‐fold more active in the nocturnal phase after administration of both 2 and 20 μg of bisphenol A than were control rats. The response was dose‐dependent. Based on DNA macroarray analyses of the midbrain, bisphenol A decreased by more than twofold gene expression levels of the dopamine D4 receptor at 4 weeks of age and the dopamine transporter at 8 weeks of age. Furthermore, bisphenol A decreased by more than twofold gene expression levels of the dopamine D4 receptor at 4 weeks of age and the dopamine transporter at 8 weeks of age. We conclude that bisphenol A affected central dopaminergic system activity, resulting in hyperactivity due most likely to a large reduction of tyrosine hydroxylase activity in the midbrain. © 2004 Wiley‐Liss, Inc.
Synaptotagmin IV overexpression inhibits depolarization‐induced exocytosis in PC12 cells
Authors: Machado Hidevaldo B. , Liu Wei , Vician Linda J. , Herschman Harvey R.
Published: April 2004

Depolarization‐induced vesicle exocytosis is a complex mechanism involving a number of proteins. In this process, synaptotagmins work as members of the Ca2+‐sensing system that triggers the fusion of the synaptic vesicle with the plasma membrane. Synaptotagmin IV (SytIV), an immediate‐early gene induced by depolarization in PC12 pheochromocytoma cells and in the hippocampus, has been suggested to work as a negative regulator of neurotransmitter release. Unlike other synaptotagmins, SytIV has an evolutionarily conserved substitution of an aspartate to a serine in the Ca2+ coordination site of its C2A domain, preventing SytIV from binding anionic lipids in a Ca2+‐dependent fashion. We used the secretion of human growth hormone (hGH) as a reporter system with which to examine the effects of overexpressing SytIV and other depolarization‐induced immediate‐early genes (the protein kinases KID‐1, SIK, and PIM‐1 and the transcription factors rTLE3 and Nurr1) on depolarization‐induced vesicle exocytosis in PC12 cells. SytIV overexpression resulted in decreased depolarization‐induced hGH release. However, conversion of the unique serine in SytIV to an aspartate eliminated this inhibitory activity. In addition, rTLE3 overexpression produced only a modest increase in spontaneous vesicle exocytosis, whereas KID‐1, SIK, PIM‐1, and Nurr1 overexpression had no effect on depolarization‐induced exocytosis. © 2004 Wiley‐Liss, Inc.
Estradiol alters transcription factor gene expression in primate prefrontal cortex
Authors: Wang J. , Cheng C.M. , Zhou J. , Smith A. , Weickert C. Shannon , Perlman W.R. , Becker K.G. , Powell D. , Bondy C.A.
Published: April 2004

Estrogen protects neurons from a variety of experimental insults in vitro, and is thought to protect from acute and chronic neurodegenerative processes in vivo. Estrogen also enhances higher‐level cognitive functions that are centered in the dorsolateral prefrontal cortex (DLPFC) in human and non‐human primates. To investigate genomic mechanisms involved in estrogenic effects on the primate brain in vivo, we compared transcription factor mRNA and protein expression in the DLPFC of ovariectomized rhesus monkeys treated with either vehicle or estradiol (E2). c‐FOS, E2F1, and general transcription factor IIB (TFIIB) mRNA and protein expression were altered significantly by short‐term E2 treatment, as shown by DNA array, in situ hybridization, and immunohistochemical and immunoblot evaluations. C‐FOS expression was increased significantly whereas E2F1 and TFIIB levels were decreased in the DLPFC of E2‐treated animals. These transcription factors were concentrated in cortical pyramids, as were estrogen receptors α and β. These data indicate that estrogen may have direct as well as indirect effects on neuronal gene expression in the primate prefrontal cortex. © 2004 Wiley‐Liss, Inc.
Cytidine‐5′‐diphosphocholine affects CTP‐phosphocholine cytidylyltransferase and lyso‐phosphatidylcholine after transient brain ischemia
Authors: Adibhatla Rao Muralikrishna , Hatcher James F. , Dempsey Robert J.
Published: April 2004

Cytidine‐5′‐diphosphocholine (CDP‐choline, also referred as citicoline), the key intermediate in phosphatidylcholine (PtdCho) synthesis, provided significant benefit in experimental central nervous system (CNS) injury including cerebral ischemia. CDP‐choline is synthesized by CTP:phosphocholine cytidylyltransferase (CCT), the key rate‐limiting enzyme in PtdCho synthesis. Phospholipase A2 (PLA2) hydrolyzes PtdCho to produce free fatty acids and lyso‐PtdCho, an inhibitor of CCT. We investigated the status of CCT and lyso‐PtdCho after 10‐min transient brain ischemia in gerbils with reperfusion up to 2 days. Ischemia with no reperfusion resulted in loss of CCT activity in cytosol (408 ± 8 pmol/min/mg protein compared to sham 695 ± 45; P < 0.01) and membrane (383 ± 61 compared to sham 532 ± 54; P < 0.05). CCT activity remained low over 24‐hr reperfusion, and returned to sham levels at Day 2 in membrane but remained low in cytosol. CDP‐choline significantly increased CCT activity in cytosol at 1 hr reperfusion (saline, 339 ± 35 compared to CDP‐choline, 430 ± 70; P < 0.05) and in membrane at 6 hr (saline, 381 ± 32 compared to CDP‐choline, 489 ± 50; P < 0.01) and 24 hr (saline, 417 ± 24 compared to CDP‐choline, 594 ± 45; P < 0.01), but had no effect on CCT activity at Day 2. Lyso‐PtdCho increased at 1‐hr reperfusion (219 ± 5 nmol/g tissue compared to sham, 92 ± 8; P < 0.01), and remained elevated over 2 days. CDP‐choline attenuated lyso‐PtdCho levels at 1‐hr reperfusion (162 ± 21, P < 0.01 compared to saline). These data indicate that PtdCho synthesis is impaired after brain ischemia, and CDP‐choline may increase PtdCho levels by attenuating the loss of CCT activity and lyso‐PtdCho formation. © 2004 Wiley‐Liss, Inc.
Effect of cell density on intracellular levels of the Alzheimer's amyloid precursor protein
Authors: Rebelo Sandra , Henriques Ana Gabriela , da Cruz e Silva Edgar F. , da Cruz e Silva Odete A.B.
Published: April 2004

The precise function of APP (Alzheimer's amyloid precursor protein) remains to be fully elucidated, but various lines of evidence suggest that it may be involved in cell adhesion processes. Because APP is a transmembrane glycoprotein, variations in its expression level may have direct bearing on its putative role in cell adhesion. Our results revealed that although APP levels did not change markedly with increasing cell density (ICD), there was a small but reproducible increase in APP expression at subconfluent conditions. Higher expression APP levels led to corresponding increases in the amount of APP processed and secreted APP (sAPP) released into the cell media. Given that phorbol esters stimulate the non‐amyloidogenic pathway at the expense of reducing production of Aβ (the peptide found deposited as neuritic plaques in the brains of patients with Alzheimer's disease), thus providing an interesting therapeutic focus, we tested the effect of the phorbol 12‐myristate 13‐acetate (PMA) on APP processing at ICD. PMA not only stimulated sAPP release at all densities tested, but also produced a corresponding decrease in the intracellular levels of APP. Further experimentation revealed that increased APP expression with ICD was dependent on factors present in conditioned medium. Interestingly, exposing cells to the Aβ peptide itself could mimic these results, thus providing evidence for a potential positive feedback mechanism between Aβ production and intracellular APP levels. © 2004 Wiley‐Liss, Inc.
Antipsychotics increase microtubule‐associated protein 2 mRNA but not spinophilin mRNA in rat hippocampus and cortex
Authors: Law Amanda J. , Hutchinson Louise J. , Burnet Philip W.J. , Harrison Paul J.
Published: April 2004

Antipsychotic (neuroleptic) drugs induce structural alterations in synaptic terminals and changes in the expression of presynaptic protein genes. Whether there are also changes in corresponding postsynaptic (dendritic) markers has not been determined. We describe the effect of 14‐day treatment with typical (haloperidol, chlorpromazine) or atypical (clozapine, olanzapine, risperidone) antipsychotics on the expression of two dendritic protein genes, microtubule‐associated protein 2 (MAP2) and spinophilin, using in situ hybridization, in the rat hippocampus, retrosplenial, and occipitoparietal cortices. MAP2 mRNA was increased modestly in the dentate gyrus and retrosplenial cortex by chlorpromazine, risperidone, and olanzapine and in the occipitoparietal cortex by chlorpromazine, haloperidol, and risperidone. None of the antipsychotics affected spinophilin mRNA in any area. Overall, these results show a modulation of MAP2 gene expression, likely reflecting functional or structural changes in the dendritic tree in response to some typical and atypical antipsychotics. The lack of change in spinophilin mRNA suggests that dendritic spines are not affected selectively by the drugs. The data provide further evidence that antipsychotics regulate genes involved in synaptic structure and function. Such actions may underlie their long‐term effects on neural plasticity in areas of the brain implicated in the pathology of schizophrenia. © 2004 Wiley‐Liss, Inc.
Impact of Labrador sea‐ice extent on the North Atlantic oscillation
Authors: Kvamstø Nils Gunnar , Skeie Paul , Stephenson David B.
Published: April 2004

The wintertime atmospheric response to imposed sea‐surface temperature and sea‐ice extent changes in the Labrador Sea has been investigated by means of ensemble simulations with an atmospheric general circulation model. Low temperatures and heavy ice conditions in the Labrador Sea produce a statistically significant (at 95% confidence) negative North Atlantic oscillation–Arctic oscillation (NAO–AO) response. Conversely, reduced sea‐ice extent in the Labrador Sea produces a positive NAO–AO response. The two simulations with opposite sea‐ice conditions in the Labrador Sea exhibit a maximum mean wintertime difference of 4–5 hPa in sea‐level pressure corresponding to a substantial and statistically significant change in the NAO–AO index of 0.7 standard deviations. The large‐scale response to a local perturbation of sea‐ice conditions is associated with marked changes in the transient eddies (synoptic storms). Changes in the sea‐ice cover cause changes in low‐level baroclinicity that perturb the travelling baroclinic disturbances, which then bring the signal downstream to manifest a non‐local Atlantic‐wide response. The atmospheric response suggests that the sea ice in the Labrador Sea is able to provide an important negative feedback on long‐term NAO–AO variations. Copyright © 2004 Royal Meteorological Society
Differential scanning calorimetric and Raman studies of a phase transition in [C3H7NH3]2SiF6
Authors: Jeghnou H. , Ouasri A. , Elyoubi M. , Rhandour A. , Dhamelincourt M.‐C. , Dhamelincourt P. , Mazzah A.
Published: April 2004

A new structural phase transition was detected at low temperatures in [C3H7NH3]2SiF6 by means of differential scanning calorimetry; the basic thermodynamic data were determined for this transition. The Raman spectra of this compound were recorded from ambient temperature through the phase transition at 223 K. The observed phase transition may be of the order–disorder type and probably of first‐order character. Copyright © 2004 John Wiley & Sons, Ltd.
Lattice dynamics of Ca4GdO(BO3)3
Authors: Ma̧czka M. , Hanuza J. , Paja̧czkowska A. , Morioka Y. , van der Maas J. H.
Published: April 2004

Polarized Raman and IR spectra were obtained for Ca4GdO(BO3)3 crystal at ambient temperature. The assignment of the observed bands to the respective internal and external phonons is proposed on the basis of lattice dynamics calculations. This study also shows that significant LO–TO splitting exists for some internal modes. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of pigments and gemstones on the Tours Gospel: the early 9th century Carolingian palette
Authors: Clark Robin J. H. , van der Weerd Jaap
Published: April 2004

Twelve gemstones set into the cover of an elaborately decorated leather‐bound manuscript, the Tours Gospel, ‘Evangelia Quatuor’, held in the British Library (Add. MS. 11848), were identified by Raman microscopy to be composed of silica, amethyst, emerald (probable, 3), iron garnet (3) and sapphire (3), one not being identified. The brilliant illuminations within the manuscript (ca 825 AD) were established by Raman studies at 215 locations on 13 folios to have been painted with a restricted palette, which included carbon black, indigo, lead white, minium, orpiment and vermilion, together with certain mixtures of the above pigments. Gold was also used but, notably, not lazurite. The palette was compared with those found for the earlier Lindisfarne Gospels (ca 715 AD), part of a later Anglo‐Saxon manuscript (ca 920 AD), a Paris Bible (1267 AD) and certain Gutenberg Bibles (1455 AD). Copyright © 2004 John Wiley & Sons, Ltd.
Raman spectroscopic study of organo‐montmorillonites
Authors: He Hongping , Frost Ray L. , Xi Yune fi , Zhu Jianxi
Published: April 2004

A Raman spectroscopic study on the organo‐montmorillonites prepared at different concentrations provided detailed observations about the ordering conformation of HDTMA+ ions confined within the montmorillonite interlayer. The ordering conformation shows a strong dependence on the concentration of the confined amine. Both the wavenumber and bandwidth of antisymmetric and symmetric stretching modes are sensitive to the ordering conformation of the inserted organic cation. Furthermore, the wavenumber of the antisymmetric stretching mode is more sensitive than that of the symmetric stretching mode to the mobility of the tail of the amine chain. At room temperature, the conformational ordering is more easily affected by the packing density in the lateral model than in the paraffin‐type model. However, at liquid nitrogen temperature, both the positions of antisymmetric and symmetric stretching modes are independent of the amine concentration, and the bandwidth of symmetric stretching mode is sensitive to the organic ordering conformation. Upon heating the organo‐montmorillonites, the positions of both the antisymmetric and symmetric stretching bands shift to higher wavenumbers, indicating a decrease of conformational ordering. Copyright © 2004 John Wiley & Sons, Ltd.
New additional cooling effect of diffusion
cooled sealed-off CO2 lasers excited by dielectric barrier
discharges at about 1 MHz with an all-solid-state generator
Authors: Wieneke S , Uhrlandt C , Viöl W
Published: April 2004

Diffusion cooled sealed-off CO2 lasers excited by a
dielectric barrier discharge with a developed all-solid-state
generator. A homogeneous discharge of hf excitation at average
electrical power density of up to 25 Wcm-3 is obtained
without applying any stabilization techniques on the discharge at
a discharge gap of d = 6 mm for the first time. A discharge gap
of d = 6 mm is used to ensure a free propagation of the laser
beam without any waveguide losses. A maximal output laser power of
70 W is attained with a laser efficiency of 8 % at an electrical
power density of 20 Wcm-3. A laser efficiency of 12.5 % is
reached at an electrical input power of 10 Wcm-3. Emission
spectroscopy is used to measure the spatially resolved electron
energy in the discharge gap at excitation frequencies between 0.4
and 2.4 MHz. It shows, that the mean electron energy lies in an
efficient range to excite CO2 lasers. An optical fibre
thermometer is used to measure the gas temperature porfile inside
the discharge gap. The measured gas temperature is 150 K below the
theoretically calculated value. A additionally cooling effect is
responsible for the low gas temperature.
Properties of Er – doped layers grown from Er: YAG (YAP) crystalline
targets by sub-picosecond laser deposition
Authors: Jelinek M , Klini A , Oswald J , Studnička V , Fotakis C , Macková A
Published: April 2004

Thin YAG
(Y3Al5O12) and YAP (YAlO3) films doped with Er content were
grown by sub-picosecond (450 fs) KrF laser deposition from
crystalline Er: YAG and Er: YAP laser rods. The influence of laser
power density, substrate temperature, target- substrate distance
and deposition ambient atmosphere (vacuum or oxygen) was studied.
Results of morphological, compositional, structural and
luminescence analysis are presented. Crystalline films have been
obtained even for low substrate temperature. Luminescence
corresponding to Er+3 ions was observed for all
the samples.
Microstructure-fiber frequency converters
Authors: Zheltikov A M
Published: April 2004

Microstructure fibers with multiple micron and
submicron fused silica waveguide channels are shown to be ideally
suited for highly efficient anti-Stokes frequency conversion.
These fibers are capable of generating ultrashort pulses of
frequency-tunable radiation with controlled chirp, allowing the
creation of new sources of tunable radiation for applications in
spectroscopy, photochemistry, optical metrology, photobiology, and
biomedicine.
Generation of radially polarized beams in Nd:YAG lasers with polarization
selective mirrors
Authors: Moser T , Ahmed M A , Pigeon F , Parriaux O , Wyss E , Graf Th
Published: April 2004

Radially polarized Nd:YAG laser emission is
demonstrated by means of a dielectric multilayer resonator mirror
that comprises a resonant corrugation grating.
Two-photon mapping of molecular orientations in hexaphenyl microrings
Authors: Beermann J , Marquart C , Bozhevolnyi S I
Published: April 2004

Using a far-field second harmonic scanning
optical microscope with a tightly focused beam being incident
perpendicular to the surface, we have observed two-photon
luminescence from microrings consisting of organic hexaphenyl
molecules that form ringlike (diameter ≈ 5 μm),
≈ 500-nm-high and very thin (100-200 nm) structures, i.e.
form rings of nanoneedles. The molecular orientation in these rings
is determined from the ratio of two-photon induced luminescence
signals for mutually perpendicular polarized excitations. We find
that, in general, the molecular orientation follows the orientation
of a nanoneedle, so that the local angle between the molecule axis
and that of the nanoneedle is kept within some limits. Our modeling
indicate that the observed deviations can be related to the
influence of a limited spatial resolution of the microscope and
fluctuations in the nanoneedle orientation with respect to an ideal
ring structure.
Laser cartilage reshaping in an in vivo rabbit model using a 1.54 μm Er:Glass laser
Authors: Mordon Serge , Wang Tao , Fleurisse Laurence , Creusy Colette
Published: April 2004

Background and Objectives

The potential applications for facial laser cartilage reshaping (LCR) have generated increasing clinical interest. This study aimed to evaluate in vivo LCR of the rabbit ear using a 1.54 µm Er:Glass laser in combination with contact cooling.

Study Design/Materials and Methods

LCR was performed in vivo on 12 rabbit ears using a 1.54 µm Er:Glass laser (Aramis, Quantel Medical, Clermont Ferrand, France) connected to a 4 mm chilled (+5°C) handpiece placed in contact to the skin. Ear curvature was predetermined using a perforated cylindrical guide also used to standardize laser beam delivery. The treatment consisted of 15 spots (3 millisecond, 7 pulses, 12 J/cm2, 2 Hz, 84/cm2 cumulative fluence) applied on 10 contiguous parallel rows along the ear. After irradiation, the aluminum jig was replaced by a holder (10 mm diameter plastic tube) maintaining the curvature. This holder was secured with sutures and covered by an adhesive gauze bandage dressing to keep new form during 7 days. In order to assess thermal damage, biopsies were taken on irradiated areas and 1 week, 3 weeks and 6 weeks and studied using haematoxylin‐erythrosin‐safran (HES) and orcein staining and PCNA to detect cells in cycle.

Results

Using the laser with the parameters given above, no immediate visible effects were observed on the skin (no swelling, no bleaching). There were also no late visible side effects like crusting, or blistering. The laser treatment produced changes in the shape of every ear after the dressing was removed. A slight tendency to recover its initial shape was observed for each ear. However, the curvature was stabilized after 10 days and the average shape retention was 64±4% at 6 weeks, with a curvature radius of 7.25±0.75 mm, instead of 5 mm initially. Histological examination of the laser irradiated side at 1 week showed an intact epidermis. A reduced inflammation process was seen in the dermis. A modification of half of the layer of cartilage was observed at the opposite side where the laser irradiation was applied and proliferative cells were detected inside. At 3 weeks, an important chondroblastic proliferation was observed around the area of contracted cartilage. At 6 weeks, significant thickening of the cartilage layer was observed (from 300 to 490 µm) and new chondrocytes were clearly seen.

Conclusions

Rabbit ear cartilage can be reshaped with an Er:Glass laser. This technique could offer exciting possibilities that may help patients whose cartilage‐lined joints have been affected by disease or trauma. This technique could be certainly utilized to correct alar cartilage deformities and septum deviation of cleft lips. Lasers Surg. Med. 34:315–322, 2004. © 2004 Wiley‐Liss, Inc.
Passive mass deposition control of cryogen sprays through the use of wire meshes
Authors: Vu Henry , Aguilar Guillermo , Stuart Nelson J.
Published: April 2004

Background and Objectives

Cryogen spray cooling (CSC) is used for epidermal protection during laser dermatologic surgery. However, further research is necessary to optimize the use of CSC for many applications, particularly in patients with darker skin types, and in procedures with deep‐targeted chromophores.

Study Design/Materials and Methods

With the objective to enhance cryogen spray atomization and introduce a passive mass deposition control, stainless steel wire meshes of various sizes were positioned in the spray path of two nozzles of different diameters (0.7 and 1.4 mm). A temperature sensor placed at a fixed distance below the nozzle tips measured variations in temperature as a function of time. Calculations for heat flux (q), and overall heat extraction (Q) were done through an inverse heat conduction problem (IHCP) algorithm.

Results

The use of wire meshes reduced maximum q and thus cooling efficiency for both nozzles. However, for the larger diameter nozzle (1.4 mm), cooling duration was prolonged significantly when compared to the case without mesh, which led to an increase in Q.

Conclusions

Wire meshes, within the range of wire diameters used, are not desirable for use with the smaller diameter nozzle because they reduce cooling efficiency. For the larger diameter nozzle, however, the prolonged cooling duration and increase in Q may be beneficial for laser dermatological procedures directed towards deeper targeted chromophores, such as hair removal. Lasers Surg. Med. 34:329–334, 2004. © 2004 Wiley‐Liss, Inc.
Inferior turbinate reduction in children using Holmium YAG laser—a clinical and histological study
Authors: Rejali S.D. , Upile T. , McLellan D. , Bingham B.J.G.
Published: April 2004

Background and Objectives

To compare the efficacy and safety of inferior turbinate reduction in children using Holmium:YAG (Ho:Yag) laser and diathermy. Histological effects of these treatments on turbinate tissue are also studied.

Study Design/Materials and Methods

A retrospective review and structured telephone interview of paediatric cases treated with Ho:Yag laser and diathermy to inferior turbinates. The complications, morbidity and efficacy were quantified. Histological sections of inferior turbinates treated with diathermy (surface and submucosal) and laser were compared.

Results

Efficacy in the laser (n = 8) and diathermy group (n = 11) was similar. The complication/morbidity score was lower in the laser group, 1.92 versus 3.48, (P = 0.04, CI: 0.01, 2). Long‐term benefit was 50 and 36% in the laser and diathermy group respectively. Histology showed very limited tissue damage in all methods of treatment.

Conclusions

Ho:Yag laser treatment is equally efficacious, but causes less complications and morbidity compared to surface diathermy. Both treatment methods have poor long‐term efficacy, which may be related to limited tissue damage. Lasers Surg. Med. 34:310–314, 2004. © 2004 Wiley‐Liss, Inc.
A Synthetic Approach to Star‐Like Polymers of Styrene and Butyl Acrylate by Linking Reactions using Functionalized Methacrylates
Authors: Böhme Karsten , Schmidt‐Naake Gudrun
Published: April 2004

Summary: Coupling reactions between terminal functionalized polymer chains were chosen for the synthesis of star‐like polymers consisting of polystyrene and polystyrene‐block‐poly[styrene‐co‐(butyl acrylate)] arms. For the preparation of terminal functionalized polymer chains a side reaction of the 2,2,6,6‐tetramethylpiperidine‐N‐oxyl (TEMPO) mediated free radical polymerization of methacrylates could be used successfully to convert TEMPO terminated polymers into end functionalized polymers. The number of functionalized monomer units attached to the polymer chain is directly related to the TEMPO concentration during this reaction. Different polystyrenes and polystyrene‐block‐poly[styrene‐co‐(butyl acrylate)] block copolymers were functionalized with a variable number of epoxide and alcohol groups at the chain end. For the determination of the optimal reaction parameters for the coupling reactions between these polymer chains, epoxy functionalized polystyrenes were converted with hydroxy functionalized polystyrenes under basic and acidic conditions. By activation with sodium hydride or boron trifluoride star‐like polymers were synthesized under mild conditions. The transfer of the reaction conditions to coupling reactions between end functionalized polystyrene‐block‐poly[styrene‐co‐(butyl acrylate)] copolymers showed that star‐like polymers with more than 12 arms were formed using boron trifluoride as activating agent.

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EVA‐Montmorillonite Nanocomposites: Effect of Processing Conditions
Authors: Gianelli Walter , Camino Giovanni , Dintcheva Nadka Tzankova , Verso Stella Lo , Mantia Francesco Paolo La
Published: April 2004

Summary: The aim of this study is to examine the effect of the compounding apparatus and of processing conditions on the properties of an organoclay‐poly[ethylene‐co‐(vinyl acetate)] (EVA) nanocomposite. The filled materials were prepared using either a discontinuous batch mixer, a single screw extruder, a counter rotating intermeshing twin‐screw compounder or a corotating intermeshing twin‐screw extruder. The characterization of the obtained nanocomposites was performed by XRD, thermogravimetry, mechanical and rheological measurements. The study has shown the possibility of producing nanocomposites based on EVA and a commercial organoclay (Cloisite 15A) by several mixing equipments. In fact all the prepared composite materials exhibit a larger interlayer clay spacing in comparison with the pristine organoclay. Moreover their elastic modulus is significantly increased from 50 to 100% depending on the processing conditions.

X‐ray diffraction of the master (Sample A) and the clay used for its preparation (Cloisite 15A).

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X‐ray diffraction of the master (Sample A) and the clay used for its preparation (Cloisite 15A).
Linear ion traps in mass spectrometry
Authors: Douglas Donald J. , Frank Aaron J. , Mao Dunmin
Published: April 2004

I.
Introduction
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 II.
Linear Multipoles
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A.  Multipole Fields
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    1.  Multipole Potentials
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    2.  Ion Motion in 2D Multipole Fields
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    3.  Ion Motion in Quadrupole Fields
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    4.  Ion Motion in Higher Multipole Fields
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    5.  Linear Ion Guides, Collision Cells, and Traps
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    6.  Collisional Cooling
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    7.  Ion Excitation in the Presence of a Collision Gas
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    8.  Ion Isolation
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    9.  Trap Capacity
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A.  Mass Discrimination Effects
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  III.
Linear Traps Combined with Other Mass Analyzers
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A.  Linear Traps Combined with 3D Paul Traps
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B.  Linear Ion Traps Combined with TOF Mass Analyzers
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C.  Linear Traps Combined with FTICR
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 IV.
Linear Traps as Mass Spectrometers
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A.  Fourier Transform Mass Spectrometry in a Linear Quadrupole Ion Trap
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B.  Linear Quadrupole Ion Trap Mass Spectrometer with Radial Ion Ejection
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C.  Linear Quadrupole Ion Trap Mass Spectrometer with Axial Ejection
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  V.
Summary and Outlook
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Acknowledgments
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List of Symbols
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References
000

Linear ion traps are finding new applications in many areas of mass spectrometry. In a linear ion trap, ions are confined radially by a two‐dimensional (2D) radio frequency (RF) field, and axially by stopping potentials applied to end electrodes. This review focuses on linear ion trap instrumentation. Potentials and ion motion in linear multipole fields and methods of ion trapping, cooling, excitation, and isolation are described. This is followed by a description of various mass discrimination effects that have been reported with linear ion traps. Linear ion traps combined in various ways with three‐dimensional (3D) traps, time‐of‐flight (TOF) mass analyzers, and Fourier transform ion cyclotron resonance mass spectrometers are then given. Linear ion traps can be used as stand alone mass analyzers, and their use for mass analysis by Fourier transforming image currents, by mass selective radial ejection, and by mass selective axial ejection are reviewed. © 2004 Wiley Periodicals, Inc., Mass Spec Rev
Multi‐criteria decision support in the liberalized energy market
Authors: Makkonen Simo , Lahdelma Risto , Asell Anna‐Maria , Jokinen Antti
Published: April 2004

The European energy market has faced a radical change during the last 10 years and the evolution will probably continue for several years. Liberalization of the electricity market, unbundling of vertically integrated businesses, scarcity of natural resources, and increasing emphasis on the environmental effects of the energy sector have created a new business environment, where complex, interacting decision problems must be solved in co‐ordination. These decision problems involve a large number of variables, multiple criteria, and they are stochastic by nature. Efficient simulation and optimization methods are required to solve these problems. It is also important that the results on the different analyses can be presented to the decision‐makers in a format that they can understand. In this paper, we focus on the strategic decision making of an electricity retailer operating in the liberalized market. We develop a decision support system based on stochastic simulation, optimization and multi‐criteria analysis. We demonstrate the use of the system through a realistic case. Copyright © 2004 John Wiley & Sons, Ltd.
Evaluation of water supply augmentation and water demand management options for the City of Cape Town
Authors: Joubert Alison , Stewart Theodor J. , Eberhard Rolfe
Published: April 2004

This paper discusses an application of MCDA to integrated water resource planning for the City of Cape Town. As a result of rapid growth in recent years, there has been increasing pressures on limited water resources, leading by the end of 2000 to severe restrictions having to be imposed on consumers. Planners needed thus to develop and to evaluate options both for water supply augmentation and for water demand management. The role of structuring these problems in MCDA terms, in order to facilitate a common understanding between a number of interest groups, is first discussed. Thereafter, the use of simple multiattribute value functions to score the various supply and demand management options in a group setting is described. One advantage of this approach was that when additional alternatives were proposed at a later date, their evaluation could easily be incorporated with the earlier results. The intention during this study was to identify high priority interventions (which may need to be implemented quickly), as well as options that are probably not worth implementing in the short term. It is recognized that at a later stage, the high priority items may need to be ‘packaged’ into a number of alternative policy scenarios, which will be evaluated in more holistic terms. At the time of writing, the results of the analysis described here had been presented as a single proposal to the city council, and have led to more detailed design studies for implementation. Copyright © 2004 John Wiley & Sons, Ltd.
Measurements of transcallosally mediated cortical inhibition for differentiating parkinsonian syndromes
Authors: Wolters Alexander , Classen Joseph , Kunesch Erwin , Grossmann Annette , Benecke Reiner
Published: April 2004

Clinicopathologic evidence suggests differential involvement of cortex and corpus callosum (CC) in various disorders presenting with a parkinsonian syndrome. We tested the hypothesis of whether neurophysiologic and morphometric assessments of CC as surrogate parameters of cortical involvement could be helpful in differential diagnosis of parkinsonian disorders. The integrity of CC was assessed neurophysiologically by measuring the ipsilateral silent period (iSP) evoked by transcranial magnetic stimulation (TMS) in a total of 25 patients with idiopathic parkinsonian syndromes (IPS), corticobasal ganglionic degeneration (CBD), progressive supranuclear palsy (PSP), or multiple system atrophy (MSA). Additionally, morphometric analyses of magnetic resonance imaging (MRI) measurements of CC was carried out in all patients. iSP was abnormal in all 5 CBD and all 5 PSP patients, whereas it was intact in all 10 IPS patients and all 5 MSA patients. Among various MRI parameters of CC, testing between different groups revealed a significant difference only for measurements of the middle part of the truncus. CBD and PSP patients exhibited a significant atrophy as compared with control subjects. These data suggest impairment of callosal integrity in patients with CBD and PSP. iSP measurements may be a useful clinical neurophysiologic test in differential diagnosis of patients with parkinsonian syndromes. © 2004 Movement Disorder Society
Modulation of two oscillatory networks in the peripheral olfactory system by γ‐aminobutyric acid, glutamate, and acetylcholine in the terrestrial slug Limax marginatus
Authors: Ito Iori , Kimura Tetsuya , Watanabe Satoshi , Kirino Yutaka , Ito Etsuro
Published: April 2004

The digit‐like extensions (the digits) of the tentacular ganglion of the terrestrial slug Limax marginatus are the cell body rich region in the primary olfactory system, and they contain primary olfactory neurons and projection neurons that send their axons to the olfactory center via the tentacular nerves. Two cell clusters (the cell masses) at the bases of the digits form the other cell body rich regions. Although the spontaneous slow oscillations and odor responses in the tentacular nerve have been studied, the origin of the oscillatory activity is unknown. In the present study, we examined the contribution of the neurons in the digits and cell masses to generation of the tentacular nerve oscillations by surgical removal from the whole tentacle preparations. Both structures contributed to the tentacular oscillations, and surgical isolation of the digits from the whole tentacle preparations still showed spontaneous oscillations. To analyze the dynamics of odor‐processing circuits in the digits and tentacular ganglia, we studied the effects of γ‐aminobutyric acid, glutamate, and acetylcholine on the circuit dynamics of the oscillatory network(s) in the peripheral olfactory system. Bath or local puff application of γ‐aminobutyric acid to the cell masses decreased the tentacular nerve oscillations, whereas the bath or local puff application of glutamate and acetylcholine to the digits increased the digits' oscillations. Our results suggest the existence of two intrinsic oscillatory circuits that respond differentially to endogenous neurotransmitters in the primary olfactory system of slugs. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 304–318, 2004