bluuebunny/crossref_metadata_2025 huggingface dataset:
Discerning between bulk diffusion and surface crossing in diffusion measurements
Authors: Burshtein Z. , Sinder M.
Published: December 2004

We propose a method for experimentally discerning between impurity bulk diffusion and surface crossing by a systematic study of diffusion in bulk samples of varying dimensions: varying thickness for the case of plane-parallel plates and varying radii for spheres and long cylinders.
Radio-frequency operation of a double-island single-electron transistor
Authors: Brenner R. , Buehler T. M. , Reilly D. J.
Published: December 2004

We present results on a double-island single-electron transistor (DISET) operated at radio frequency (rf) for the fast and highly sensitive detection of charge motion in the solid state. Using an intuitive definition for the charge sensitivity, we compare a DISET to a conventional single-electron transistor (SET). We find that a DISET can be more sensitive than a SET for identical, minimum device resistances in the Coulomb blockade regime. This is of particular importance for rf operation, where ideal impedance matching to 50-Ω transmission lines is only possible for a limited range of device resistances. We report a charge sensitivity of 5.6×10−6e∕Hz for a rf-DISET, together with a demonstration of the single-shot detection of small (⩽0.1e) charge signals on microsecond time scales.
Dissipative solitons driving and bound state control via parameter gradients
Authors: Bortolozzo U. , Ramazza P. L. , Boccaletti S.
Published: December 2004

The effect of phase and intensity gradients on the motion of dissipative solitons in a nonlinear interferometer is investigated. We show how the forces exerted by parameter gradients on the solitons alter their interactions. Consequently, it is possible to tune the spectrum of soliton bound states via the introduction of proper spatial distribution of the system parameters. Furthermore, we show how the use of properly shaped parameter distributions can lead to a relevant reduction of the cross-talk between close by solitons in applications.
A SEMI-LOCALIZED ELASTIC NET FOR SURFACE RECONSTRUCTION OF OBJECTS FROM MULTISLICE IMAGES
Authors: DAMPER ROBERT I. , GILSON STUART J. , MIDDLETON IAN
Published: December 2004

The traveling salesman problem (TSP) is a prototypical problem of combinatorial optimization and, as such, it has received considerable attention from neural-network researchers seeking quick, heuristic solutions. An early stage in many computer vision tasks is the extraction of object shape from an image consisting of noisy candidate edge points. Since the desired shape will often be a closed contour, this problem can be viewed as a version of the TSP in which we wish to link only a subset of the points/cities (i.e. the "noisefree" ones). None of the extant neural techniques for solving the TSP can deal directly with this case. In this paper, we present a simple but effective modification to the (analog) elastic net of Durbin and Willshaw which shifts emphasis from global to local behavior during convergence, so allowing the net to ignore some image points. Unlike the original elastic net, this semi-localized version is shown to tolerate considerable amounts of noise. As an example practical application, we describe the extraction of "pseudo-3D" human lung outlines from multiple preprocessed magnetic resonance images of the torso. An effectiveness measure (ideally zero) quantifies the difference between the extracted shape and some idealized shape exemplar. Our method produces average effectiveness scores of 0.06 for lung shapes extracted from initial semi-automatic segmentations which define the noisefree case. This deteriorates to 0.1 when extraction is from a noisy edge-point image obtained fully-automatically using a feedforward neural network.
A FINITE ELEMENT STRUCTURAL-ACOUSTIC MODEL OF COUPLED MEMBRANES
Authors: MAR-OR ASSAF , GIVOLI DAN
Published: December 2004

A simple model displaying structural-acoustic behavior is considered. The model comprises of two parallel infinitely-long flat membranes lying on elastic foundations and the acoustic medium separating them. The structural-acoustic coupling manifests itself in that a vibrational excitation of one of the membranes triggers vibrations in the other. The governing equations are stated, and the associated finite element formulation is constructed. The model is then analyzed numerically and its vibrational properties are investigated. The proposed model is especially simple, being two-dimensional and involving a small number of parameters, but at the same time it brings to light some important features associated with structural-acoustic coupling. Therefore it may serve as a benchmark for evaluating structural-acoustic numerical schemes and as an educational tool for studying structural-acoustic coupling in a simple context.
ULTRASONIC IMAGING SYSTEM USING A 2D ENVELOPE BEAMFORMING TECHNIQUE: IN-HOMOGENEITIES LOCATION
Authors: MEDINA L. , MORENO E.
Published: December 2004

An algorithm has been developed to implement synthetic aperture focusing technique for B-scan. This is made at a several transmitter/receiver locations to form a map of ultrasonic reflectivity on the insonified region, considering the path travelled by the ultrasonic pulse from the transducer to the target and back again. To reconstruct the image, a time domain beam-former is applied to the envelope of the detected signals. This method minimizes the side-lobe amplitude and the restriction of λ/2 distance between two adjacent transducer positions can be neglected without loosing image resolution.

The present work is focused on the location of the in-homogeneities, caused by the presence of a phantom immersed in a water tank. The results are presented when the distance between two adjacent transducer positions are varied from 0.5λ to 2.5λ showing that the longitudinal resolution is not affected but the lateral resolution becomes poorer when the distance is about 2λ. The error in the longitudinal location of in-homogeneities is within the minimum detectable distance of the system, while the lateral location error is increased when the distance between any two adjacent transducer positions is larger than 1.5λ.
UNUSUAL ELECTRONIC AND PHOTONIC BEHAVIORS OF LINEAR POLY(SILOLYLACETYLENE)S AND HYPERBRANCHED POLY(SILOLYLENEARYLENE)S
Authors: HÄUßLER MATTHIAS , CHEN JUNWU , LAM JACKY W. Y. , TANG BEN ZHONG
Published: December 2004

A series of dendritic 2,3,4,5-tetraphenylsiloles (1–8) are prepared. Polymerizations of 4-8 are effected by transition-metal catalysts, giving linear (9-12) and hyperbranched polymers (14) in high yields. Whereas the silole polymers are practically nonluminescent when molecularly dissolved, they become emissive when aggregated in poor solvents or cooled to low temperatures. The light-emitting diodes using linear poly(silolylacetylene)s as active layers emit blue and green lights with current efficiency up to 1.45 cd/A. The hyperbranched poly(silolenearylene)s are nonlinear optically active and strongly attenuate the optical power of intense laser pulses, whose optical limiting performances are superior to that of C 60, a well-known optical limiter.
ENHANCED SHG IN POLYELECTROLYTE COMPLEXED HEMICYANINE DYE LANGMUIR–BLODGETT FILMS
Authors: CHANDRA M. SHARATH , OGATA Y. , KAWAMATA J. , RADHAKRISHNAN T. P.
Published: December 2004

Complexation of ionic amphiphiles at the air–water interface by polyelectrolytes in the subphase has a pronounced effect of stabilization and deaggregation on the amphiphiles. We have effectively utilized the latter in the case of a hemicyanine dye based amphiphile. The aggregation of these amphiphiles is influenced by the rate of equilibration of the Langmuir film and the introduction of polyelectrolytes in the subphase is found to be a convenient method to suppress the aggregation. Langmuir–Blodgett films obtained by transfer of the polyelectrolyte complexed amphiphiles show enhanced second harmonic generation.
MORPHOLOGY AND CHARACTERIZATION OF POLYIMIDE/POLYSILSESQUIOXANE HYBRID FILMS WITH MESO/MACRO DOUBLE POROUS STRUCTURE
Authors: KIM KYUNG-IL , LEE JUN-YOUNG , AN JOON-HYUN , KIM JUNG-HYUN
Published: December 2004

Supercritical CO 2 ( ScCO 2) can dissolve organic materials easily just by changing temperature and pressure. This property of ScCO 2 can be applied to extract some ScCO 2-philic organic molecules from matrix material. The ScCO 2 was used to generate the meso/macro double porous structure of polyimide/polysilsesquioxane (PI/PSSQ) hybrid film. The morphology of the porous structure was measured by scanning electron microscope (SEM). Here, we demonstrate that the ScCO 2 could penetrate into the hybrid thin film and take away the small molecules, which are the by-product ( CO 2) from the imidization reaction of the PI segment and the solvent remained in the PSSQ segment by sol-gel process.
GROWTH AND PLANAR STRUCTURING OF DAST CRYSTALS FOR OPTICAL APPLICATIONS
Authors: MUTTER LUKAS , DITTRICH PHILIPP , JAZBINŠEK MOJCA , GÜNTER PETER
Published: December 2004

The organic salt 4-N, N-dimethylamino-4′-N′-methyl stilbazolium tosylate (DAST) is a nonlinear optical crystal with superior properties for integrated electro-optical applications and THz-devices. High quality DAST single crystals have been grown by the solution growth method. The electro-optical properties were determined in the spectral range between 700 and 1535 nm (r111=47±8 pm / V at λ=1535 nm ). Several planar structuring techniques for integrated optics applications based on DAST have been investigated. The production of single crystal thin films with minimal thicknesses of 10 μm is presented as well as the channel waveguide structuring of DAST surfaces by photobleaching techniques in the depth range of 0.2 up to 2.6 μm and by femtosecond laser ablation.
TIP-ENHANCED NEAR-FIELD CARS MICROSCOPY
Authors: KAWATA SATOSHI , ICHIMURA TARO , HAYAZAWA NORIHIKO , INOUYE YASUSHI , HASHIMOTO MAMORU
Published: December 2004

We apply the field enhancement effect due to plasmon polariton excitation on a metallic nanostructure in order to improve the diffraction limited spatial resolution of coherent anti-Stokes Raman scattering (CARS) microscopy. A cantilever probe tip coated with a 25 nm-thick gold film is utilized as a near-field light source to locally excite the CARS polarizations near the tip. Our CARS microscope has effectively enhanced the CARS signals and realized vibrational imaging of single-wall carbon nanotubes (SWNTs) beyond the spatial resolution of far-field CARS microscopy.
ELECTROLUMINESCENT PROPERTIES OF OLEDS USING 1,2-BBPE DERIVATIVES
Authors: YOUN SUK-WON , RYU GWEON YOUNG , SHIN DONG-MYUNG
Published: December 2004

We fabricated the organic light emitting diodes (OLEDs) using 1,2-BBPE (1,2-bis-biphenyl ethene) derivatives as a blue emitting material, which was synthesized from the 4,4′-dibromo stilbene. The methyl and tert-butyl groups were incorporated at the 4″ and 4‴ positions of 1,2-BBPE: 1,2-bis(4″,4‴-dimethylbiphenyl)ethene (BMBPE) and 1,2-bis(4″,4‴-di-tert-butylbiphenyl)ethene (BTBBPE). Photo-luminescence (PL) maxima were 439 nm for BMBPE and 425 nm for BTBBPE deposited as a film with the thickness of 1000 Å. The single-layer device fabricated with BMBPE exhibited electroluminescent (EL) maxima at 440 and 422 nm. The brightness of the luminescence observed from the device was 50 cd under 19 V. The FWHM (full-width half-maximum) observed from the EL device was 55 m. The luminescence intensity generated from the OLED made with a single BBPE layer emitted low intensity light at 422 and 442 nm and the FWHM was 61 nm. The multi-layer device with NPB , Alq 3, BCP for the hole blocking layer and BTBBPE as emission material showed luminescence intensity over 2000 Cd/m2. We investigated the luminescence property as a function of device structure, such as layer thickness, chemical structure dependence.
TPD-BASED BLUE ORGANIC LASERS
Authors: DÍAZ-GARCÍA MARÍA A. , CALZADO EVA M. , VILLALVILLA JOSÉ M. , BOJ PEDRO G. , QUINTANA JOSÉ A. , KUZYK MARK
Published: December 2004

Laser action at 420 nm is observed in photopumped polymer films of polystyrene (PS) doped with the hole-transporting organic molecule N,N′-bis(3-methylphenyl)-N,N′-dyphenylbenzidine (TPD). Measurements of the dependence of signal on the length of the pump stripe show that the mechanism responsible for the observed spectral collapse is amplified spontaneous emission (ASE). By fitting the evolution of the output intensity at 420 nm with the excitation length, gain coefficients up to 16 cm-1 are measured.
STUDY OF INTRAMOLECULAR HYDROGEN BONDING IN ORTHO-SUBSTITUTED ACETANILIDE COMPOUNDS USING COMPUTATIONAL METHODS
Authors: JALILI SEIFOLLAH , AKHAVAN MOJDEH
Published: December 2004

The intramolecular hydrogen bonding formation in ortho-substituted compounds of Acetanilide, ortho-hydroxy Acetanilide and ortho-nitro Acetanilide, was investigated using Density Functional Theory (DFT), Møller-Plesset second-order (MP2) method and "Atoms in Molecules (AIM)" theory. It was found that in each case, the cis isomer is more stable than the trans isomer and ortho-nitro Acetanilide forms a stronger hydrogen bond than ortho-hydroxy Acetanilide. The effects of hydrogen bonding on structural parameters of the considered systems were studied using Becke's functional (B3LYP) and at the ab initio MP2 level in conjunction with different basis sets and suitable structural factors. The results are in agreement with the results of AIM theory.
SOLVENT REORGANIZATION ENERGY WITH DIELECTRIC GREEN FUNCTIONAL AND ITS APPLICATION TO RETURN ELECTRON TRANSFER IN TETRACYANOETHYLENE-HEXAMETHYLBENZENE SYSTEM
Authors: ZHU QUAN , FU KE-XIANG , LI XIANG-YUAN , LIU JI-FENG
Published: December 2004

Based on classical electrodynamics, the proper integral formula for general cases is adopted to estimate the electrostatic free energy difference between two given states, e.g. equilibrium and non-equilibrium states in the charging process of solute molecule in solution. With adequate consideration of the change of dielectric property in establishing the non-equilibrium state, the electrostatic free energy for this state can be obtained in a form differing from the traditional theories. The general formula of the solvent reorganization energy is derived according to the definition of the free energy difference between the non-equilibrium and equilibrium states due to the same electronic state of the solute molecule. Applying it to the two-sphere model and single-sphere model, we obtain the new expressions of the solvent reorganization energy, which are convenient to be used in practice. In the investigation of the return electron transfer of tetracyanoethylene-hexmethylbenzene system, good results can be obtained by using our expression when they are compared with those from the experiment.
MECHANISTIC STUDY OF HIV-1 REVERSE TRANSCRIPTASE AT THE ACTIVE SITE BASED ON QM/MM METHOD
Authors: RUNGROTMONGKOL THANYADA , HANNONGBUA SUPA , MULHOLLAND ADRIAN
Published: December 2004

HIV-1 RT catalyses the reverse transcription of viral genetic material (RNA) into double-stranded DNA, and is an important target of antiviral therapy in the treatment of AIDS. Better understanding of the structure, mechanism and functional role of residues involved in the resistance of HIV-1 RT against nucleoside-analog drugs may assist in the development of improved inhibitors, and also in understanding the effects of genetic variation on RT specificity and activity. In this study, firstly, molecular dynamics simulations (with CHARMM27) have been used to investigate binding interactions at the active site and the conformational behavior of the enzyme, then, mechanisms of deprotonation and DNA polymerization reactions have been modelled by the QM/MM method. A combined quantum mechanical and molecular mechanical (QM/MM) method (AM1/CHARMM) has been used to study the triphosphate substrate and the active site of HIV-1 reverse transcriptase complex structure, a virally-encoded enzyme. Free energy profiles for the reaction are also calculated. The obtained results provide important insight into the mechanistic activity of HIV-1 RT.
Serum Antibodies to Retinal Antigens in Lung Cancer and Sarcoidosis
Authors: Jankowska R. , Witkowska D. , Porębska I. , Kuropatwa M. , Kurowska E. , Gorczyca W.A.
Published: December 2004

Objective: Autoantibodies to various neuronal proteins frequently accompany lung cancer and their appearance may precede cancer symptoms. In this study we examined which retinal antigens (RAs) are recognized by sera of patients with lung cancer and whether the occurrence of serum antibodies to particular RAs is characteristic for cancer in comparison with a noncancer lung disease. Methods: Sera of 72 patients with non-small-cell lung cancer (NSCLC), 29 with small-cell lung cancer (SCLC), 27 with sarcoidosis (S), and sera of 32 healthy donors were examined in immunoblotting using retinal extracts and purified RAs as antigens. Results: 69.0% of SCLC, 45.8% of NSCLC, and 44.4% of S sera displayed anti-RAs reactivity. Significantly less (p < 0.05; χ2 test) percent of healthy control sera reacted with RAs. Lung cancer sera recognized mainly 46-, 56-, and 36-kD and to a smaller extent also 96-, 72-, 43-, and 26-kD proteins. Most of them were recognized with about 2-fold lower frequencies by S and control sera. Only lung cancer sera contained very high-titer antibodies to 46- and 26-kD RAs, identified as α-enolase and recoverin, respectively. Conclusion: Antibodies to RAs occur more frequently and in higher titers in lung cancer (especially SCLC) than in sarcoidosis or control sera. Although antibodies to retinal α-enolase, recoverin and other RAs are present mainly or exclusively in lung cancer sera, none of them seems to be a specific marker of a particular disease.
Quantification of Blood-Aqueous Barrier Breakdown after Phacoemulsification in Fuchs’ Heterochromic Uveitis
Authors: Nguyen Nhung X. , Küchle Michael , Naumann Gottfried O.H.
Published: December 2004

Purpose: To quantify the breakdown of the blood-aqueous barrier (BAB) following phacoemulsification with posterior chamber lens implantation in eyes with Fuchs’ heterochromic uveitis (FHU). Patients and Methods: In this retrospective study, 19 eyes of 19 patients with FHU (mean age 38 ± 14 years) and 35 eyes of 35 patients with senile cataracts (mean age 63 ± 9 years) underwent phacoemulsification with one-piece PMMA posterior chamber lens implantation. Aqueous flare was quantified using the laser flare-cell meter (LFCM, Kowa FC-1000) following medical pupillary dilation preoperatively and 1, 3, and 5 days, then 1 and 6 weeks and 6 months postoperatively. Results: Mean preoperative aqueous flare (in photon counts per millisecond) in FHU vs. controls was 11.7 ± 3.5 vs. 5.8 ± 1.7. Following cataract surgery, mean aqueous flare increased to 27.8 ± 4.4 vs. 16.0 ± 4.5 on day 1, decreased to 23.6 ± 4.0 vs. 11.8 ± 3.5 on day 3, and to 18.0 ± 3.0 vs. 9.5 ± 1.7 on day 5. In FHU eyes, it was 13.9 ± 2.7 after 1 week, and had returned to preoperative levels after 6 weeks (10.9 ± 2.5) and remained stable for up to 6 months (mean 10.3 ± 2.2). Pre- and postoperatively, aqueous flare values were 2–3 times higher in FHU eyes than in control eyes with senile cataract (p = 0.01). No postoperative complications such as fibrin formation, synechiae, macrophages on the intraocular lens optic or endophthalmitis were observed in any of the patients. Conclusions: BAB breakdown following phacoemulsification with posterior chamber lens implantation is relatively mild in eyes with FHU and the BAB appears to be fully reestablished to preoperative levels 6 weeks postoperatively, explaining the usually good outcome of cataract surgery in this condition.
Renal Advances in Ultrasound Elasticity Imaging: Measuring the Compliance of Arteries and Kidneys in End-Stage Renal Disease
Authors: Weitzel W.F. , Kim K. , Rubin J.M. , Xie H. , O’Donnell M.
Published: December 2004

Background/Aims: Ultrasound elasticity imaging visually represents tissue hardness measurements using high-resolution ultrasound speckle-tracking algorithms. This method has recently been applied in the renal setting to measure arterial compliance in end-stage renal disease (ESRD) and the mechanical properties of transplant kidneys in vivo. Methods: Ultrasound radio-frequency signal measurements were made of the brachial artery in 5 ESRD subjects and 5 healthy controls and renal transplant measurements in 2 subjects, 1 with chronic allograft nephropathy (CAN) and 1 with normal graft function. Results: Maximal brachial artery percent strain measurements for healthy controls were 32.9 ± 10.2% (mean ± SD) and for ESRD subjects maximal percent strains were 4.9 ± 1.8%. Transplant renal cortical strain for the subject with CAN was approximately one third that of the healthy transplant recipient. Conclusion: Ultrasound elasticity imaging offers the potential to noninvasively measure the mechanical properties of structures within the body.
Access Monitoring Does Not Really Improve Outcomes
Authors: Paulson William D.
Published: December 2004

It is widely accepted that hemodialysis access monitoring combined with preemptive percutaneous transluminal angioplasty (PTA) improves outcomes. The many studies that have evaluated monitoring during the last decade provide an opportunity to examine whether this hypothesis is valid. Because synthetic grafts are more likely than autogenous arteriovenous fistulas to benefit from monitoring, this review is restricted to grafts. Recent studies show that monitoring does not accurately predict graft thrombosis or failure, nor does it prolong graft life. However, monitoring can reduce thrombosis, and thereby reduce access-related hospitalizations and use of central venous dialysis catheters. Because preemptive PTA is expensive, however, monitoring does not reduce the cost of access-related care. The limited benefit that monitoring provides emphasizes the urgent need to develop better approaches to solving the problem of graft thrombosis and failure.
Effect of Daily Hemodialysis on Monocytes Apoptosis
Authors: Andrikos Emilio , Buoncristiani Emanuela , D’Intini Vincenzo , Bordoni Valeria , Bonello Monica , Levin Nathan , Buoncristiani Umberto , Pappas Michail , Ronco Claudio
Published: December 2004

Uremia is associated with a state of immune dysfunction with increased susceptibility to infection and malignancy possibly related to dysregulation of immune system cell apoptosis. Peritoneal dialysis can restore plasma apoptosis activity on monocytes compared to intermittent hemodialysis. Whether the continuous modality or diverse clearance mechanisms involved are responsible is unknown. Apoptosis rates correlate with phagocytic function highlighting the benefit of efficient toxin clearance. The plasma of 16 patients on daily hemodialysis (D-HD) was incubated with U937 monocytes and compared to 18 hemodialysis (HD) patients, 5 chronic renal failure (CRF) subjects and 5 healthy volunteers (controls). Apoptosis was evaluated by immunofluorescence microscopy dyes (Hoechst 33342, propidium iodide) and annexin V cytoflowmetry at 96 h. Plasma-induced U937 apoptosis (mean values) was significantly enhanced in D-HD (18.8 ± 4.1), HD (19.67 ± 5.5) and CRF patients (20.8 ± 4.7) compared to controls (9.6 ± 3.6; p < 0.05 for CRF vs. controls, HD vs. controls and D-HD vs. controls). No significant differences were observed between D-HD, HD and CRF sera on apoptosis rate, caspase-3 activity and phagocytic capacity of U937 monocytes. This study demonstrates that the plasma of various HD schedules was unable to reduce monocyte apoptosis induced by uremia.
Well-Being Therapy of Generalized Anxiety Disorder
Authors: Fava Giovanni A. , Ruini Chiara , Rafanelli Chiara , Finos Livio , Salmaso Luigi , Mangelli Lara , Sirigatti Saulo
Published: December 2004

Background: There is increasing awareness that the goal of treatment in generalized anxiety disorder (GAD) should not simply be a response, but restoration of normal function. The aim of this study was to apply a novel psychotherapeutic approach for increasing the level of remission in GAD. Methods: Twenty patients with DSM-IV GAD devoid of comorbid conditions were randomly assigned to 8 sessions of cognitive behavioral therapy (CBT) or the sequential administration of 4 sessions of CBT followed by other 4 sessions of well-being therapy (WBT). Assessment methods included the Anxiety and Depression Scales of Paykel’s Clinical Interview for Depression, Ryff’s Psychological Well-being Scales and Kellner’s Symptom Questionnaire. A one-year follow-up was undertaken. Results: Significant advantages of the CBT-WBT sequential combination over CBT only were observed with both observer and self-rated methods after treatment. Such gains were maintained at follow-up. Conclusions: These preliminary results suggest the feasibility and clinical advantages of adding WBT to the treatment of GAD. They lend support to a sequential use of treatment components for achieving a more sustained recovery.
Molecular Analysis of NPHS2 and ACTN4 Genes in a Series of 33 Italian Patients Affected by Adult-Onset Nonfamilial Focal Segmental Glomerulosclerosis
Authors: Aucella Filippo , De Bonis Patrizia , Gatta Giuseppe , Muscarella Lucia Anna , Vigilante Mimmo , di Giorgio Giuseppe , D’Errico Michele , Zelante Leopoldo , Stallone Carmine , Bisceglia Luigi
Published: December 2004

Background: Mutations in the NPHS2 gene, encoding podocin, and in the ACTN4 gene, encoding α-actinin-4, have been identified in familial childhood-onset forms of focal and segmental glomerulosclerosis (FSGS). NPHS2 may be also responsible for some sporadic cases. The role of NPHS2 and ACTN4 in the adult sporadic form of the disease is being clarifying. Methods: Thirty-three adult subjects affected by sporadic FSGS were studied at molecular level. At biopsy, 12 patients had nephrotic syndrome, 5 patients had isolated proteinuria and 16 patients showed proteinuria and hematuria. Glomerular filtration rate (GFR) was in the normal range in 19 subjects and 14 patients had a variable degree of renal failure. Multiplex families presenting with a clear familial inheritance for proteinuria or other congenital nephrotic syndrome were excluded. The whole coding region, all intron/exon boundaries and flanking intronic regions of NPHS2 gene and the exon 8, i.e. hot-spot mutations of the ACTN4 gene, were analyzed in all patients by denaturing high-performance liquid chromatography (DHPLC) to search disease-causing defects. Results: The analysis identified four already described and two new polymorphisms, IVS3–21C>T and IVS3–46C>T, on the NPHS2 gene. Moreover, the R229Q allele was identified in 3/33 patients and in 7/124 controls, accounting for an allelic frequency of 0.045 and 0.028, respectively. The new intronic polymorphism IVS7–54C>T was also found in the exon 8 of the ACTN4 gene. Conclusions: In this study, we exhaustively analyzed the NPHS2 and the exon 8 of the ACTN4 genes in a series of sporadic ‘adult-onset’ FSGS patients. No causative mutations were found while the R229Q allele was identified in 3 patients confirming its possible role as a ‘disease-associated NPHS2 allele’ although its pathogenetic involvement needs to be further clarified. Moreover, the description of new intronic polymorphisms in both genes is reported.
Association Analysis of Apolipoprotein E Genotype and Risk of Depressive Symptoms in Alzheimer’s Disease
Authors: Craig David , Hart Dominic J. , McIlroy Stephen P. , Passmore A. Peter
Published: December 2004

Objectives: Behavioural and psychological symptoms of dementia (BPSD) are potent predictors of carer distress and admission to institutional care. In Alzheimer’s disease (AD), depressive symptoms are one of the most common complaints affecting around 50% of all patients. There is speculation these symptoms result from known genetic risk factors for AD, therefore we investigated the role of apolipoprotein E Ε4 in the aetiology of depression in AD. Methods: In this well-characterised cohort (n = 404) from the relatively genetically homogeneous Northern Ireland population, we tested the hypothesis that genetic variants of apolipoprotein E influence the risk for depressive symptoms in AD patients using the Neuropsychiatric Inventory (NPI-D) to determine the presence of depressive symptoms during the dementing illness. Results: A total of 55% of patients exhibited a history of depression/dysphoria during the course of the illness as gathered by the NPI-D questionnaire. Forty-six percent were suffering from depression/dysphoria when the analysis was restricted to the month prior to interview. No statistically significant association between genotypes or alleles of apolipoprotein E and depression/dysphoria in AD was observed, nor was any association noted between the presence of severe symptoms and genotypes/alleles of apolipoprotein E. Conclusions: These results suggest apolipoprotein E genotype creates no additional risk for depressive symptoms in AD.
Nonassociation of Interleukin 4 Intron 3 and 590 Promoter Polymorphisms with Bronchopulmonary Dysplasia for Ventilated Preterm Infants
Authors: Lin Hung-Chih , Su Bai-Horng , Chang Jeng-Sheng , Hsu Chin-Moo , Tsai Chang-Hai , Tsai Fuu-Jen
Published: December 2004

Interleukin 4 (IL-4) stimulates and amplifies the inflammatory response, stimulates collagen synthesis in fibroblasts, promotes the progression to fibrosis and has been shown to inhibit the production of several inflammatory cytokines in the development of bronchopulmonary dysplasia (BPD) and airway hyperreactivity. We aimed to investigate whether IL-4 polymorphisms in ventilated preterm infants were associated with BPD. BPD was defined as infants who remained dependent on active respiratory support or oxygen supplementation at 36 weeks postconceptional age. A case-control study of 224 preterm infants (<30 weeks) who had respiratory distress syndrome and needed intermittent mandatory ventilation (IMV) were undertaken between January 1999 and December 2003. The typing of each genetic polymorphism was performed by polymerase-chain-reaction-based restriction analysis. Genotype distribution and allelic frequencies were compared between ventilated preterm infants who developed BPD and those who did not and the duration of IMV. The demography of these ventilated BPD and non-BPD preterm infants was not different. We observed no significant differences in genotype distribution or allelic frequency of the IL-4 intron 3 or IL-4 promoter polymorphisms between ventilated preterm infants who developed BPD and who did not. There was no significant association of the genotype or allelic frequency of IL-4 polymorphism with duration of IMV. We conclude that neither IL-4 intron 3 nor the 590 promoter polymorphism is a useful marker for predicting the susceptibility to BPD in ventilated Taiwanese preterm infants.
Protective Effects of Antioxidant Raxofelast in Alcohol-Induced Liver Disease in Mice
Authors: Altavilla Domenica , Marini Herbert , Seminara Paolo , Squadrito Giovanni , Minutoli Letteria , Passaniti Maria , Bitto Alessandra , Calapai Gioacchino , Calò Margherita , Caputi Achille P. , Squadrito Francesco
Published: December 2004

We investigated the effect of raxofelast on lipid peroxidation inhibition in mice exposed to chronic ethanol. Female C57BL/6 mice were fed a modified Lieber-DeCarli liquid ethanol (ETOH) or control diet (sham ETOH) for up to 14 days. Animals were assigned to receive either raxofelast (20 mg/kg/day i.p.) or its vehicle (DMSO:NaCl 0.9% 1:1, v:v; 1 ml/kg i.p.). Serum alanine aminotransferase (ALT), plasma and liver triglyceride levels, hepatic malondialdehyde (MDA), reduced glutathione (GSH) concentrations, liver gene expression of Toll-like receptor-4 (TLR-4), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) were studied at the end of the study. A histological evaluation of liver damage was also carried out. Raxofelast, an analog of vitamin E, blunted the increased hepatic nuclear factor-ĸB activity, reduced serum ALT, plasma and liver triglycerides, lowered hepatic MDA levels, prevented liver GSH depletion and decreased TLR-4, TNF-α, IL-6 and ICAM-1 hepatic gene expression. Furthermore raxofelast ameliorated liver damage. Our results suggest that raxofelast blunts the inflammatory cascade and organ damage during chronic ethanol exposure.
Angiotensin II-Mediated Constriction of Afferent and Efferent Arterioles Involves T-Type Ca2+ Channel Activation
Authors: Feng Ming-Guo , Navar L. Gabriel
Published: December 2004

Background/Aims: Previous studies have shown that L-type Ca2+ channel (LCC) blockers prevent the afferent arteriolar (AA) vasoconstriction elicited by angiotensin II (Ang II), but do not influence its vasoconstrictor effect on efferent arterioles (EA). The present study tested the hypothesis that Ang II-mediated constriction of AA and EA involves T-type Ca2+ channel (TCC) activation, which may mediate Ca2+ entry responsible for Ang II-induced EA and possibly AA constriction. Methods: Video-microscopic measurements of vascular dimensions were performed on isolated blood-perfused juxtamedullary nephrons from Sprague-Dawley rats. Single AA or EA were visualized and superfused with solutions containing Ang II alone or with a TCC blocker, pimozide, or a LCC blocker, diltiazem. Results: Pimozide at 10 µmol/l significantly dilated EA (19.7 ± 1.4%) as well as AA (24.8 ± 3.6%). In response to superfusion with Ang II at concentrations of 0.1, 1.0 and 10.0 nmol/l, AA diameter decreased significantly by 15.2 ± 1.7, 23.3 ± 3.2 and 36.1 ± 3.4% and EA diameter also decreased significantly by 11.9 ± 1.7, 19.6 ± 2.8 and 31.0 ± 2.6%, respectively. Pimozide (10 µmol/l) markedly blunted AA (4.6 ± 1.2, 7.5 ± 0.6 and 7.9 ± 1.2%) and EA (2.2 ± 0.6, 5.4 ± 1.5 and 7.7 ± 1.3%) diameter responses to Ang II. Diltiazem (10 µmol/l) significantly dilated AA (26.8 ± 2.2%), and prevented Ang II-mediated constriction of AA. In contrast, diltiazem did not dilate EA (3.3 ± 0.6%) and failed to inhibit the Ang II-induced EA vasoconstriction; however, the vasoconstriction was reversed by the subsequent addition of pimozide (5 µmol/l). Conclusion: This study provides further functional evidence for TCC channels in the regulation of AA and EA indicating that Ang II-mediated arteriolar constriction may involve activation of TCC in both AA and EA. TCC may play an important role in mediating Ca2+ entry responsible for Ang-induced EA and AA constriction. The role of TCC in mediating Ang II-constrictor actions on EA may be of particular significance because LCC are not normally functional in these vessels.
Exploration of the Basolateral Chloride Channels in the Renal Tubule using
Authors: Teulon Jacques , Lourdel Stéphane , Nissant Antoine , Paulais Marc , Guinamard Romain , Marvao Pedro , Imbert-Teboul Martine
Published: December 2004

Chloride channels located on the basolateral membrane are known to be involved in chloride absorption in several parts of the renal tubule, and particularly in the thick ascending limb and distal convoluted tubule. The data available suggest that the ClC-K channels play the major role in this process. We provide here a description of the electrophysiological properties of these channels, still very incomplete at this stage, and we attempt to compare ClC-Ks to three chloride channels that we have identified in the basolateral membrane of microdissected fragments of the mouse renal tubule using the patch-clamp technique. Based on anion selectivity and dependence on external pH and calcium shown by the ClC-Ks, we propose candidate ClC-K1 and ClC-K2 in native tissue. We also discuss the possibility that chloride channels that do not belong to the ClC family may also be involved in the absorption of chloride across the cortical thick ascending limb.
The Effect of Adult Hemoglobin on Red Blood Cell Nitric Oxide Levels during Fetal Development
Authors: Bard Harry , English Ann M. , Gagnon Carmen , Bellemin Karine
Published: December 2004

Objective: To compare the levels of S-nitrosohemoglobin (HbSNO) at different gestational ages in newborn infants and correlate the levels of HbSNO with HbA and HbF. Method: Cord blood samples of 22 newborn infants of different gestational ages (25–41 weeks) were analyzed. The levels of HbF and HbA were determined by HPLC and of HbSNO by chemiluminescence. Results: The level of HbSNO varied from 28.1 to 145.3 nM. There was a significant correlation with gestational age (r2 = 0.5469, p < 0.0001) and with the relative amount of HbA (r2 = 0.8144, p < 0.0001). Conclusion: The increases in HbSNO in fetal red cells is directly related to the relative amount of HbA.
Folate Deficiency Increases Postischemic Brain Injury
Authors: Endres Matthias , Ahmadi Michael , Kruman Inna , Biniszkiewicz Detlev , Meisel Andreas , Gertz Karen
Published: December 2004

Background and Purpose—

Folate deficiency and resultant hyperhomocysteinemia impair vascular function and increase stroke risk. We tested the hypothesis that folate deficiency and high homocysteine levels promote DNA damage and increase brain injury after cerebral ischemia/reperfusion.

Methods—

129/Sv mice, uracil-DNA glycosylase–deficient (
Ung
−/−
) mice, and
Ung
+/+
littermate mice were exposed to a folate-deficient diet for 3 months and then subjected to 30-minute middle cerebral artery (MCA) occlusion and reperfusion. Plasma homocysteine levels and physiological parameters were measured in selected animals. Outcome measures were neurological sensorimotor deficits, infarct size measured by computer-assisted volumetry, and oxidative DNA damage measured by a colorimetric assay.

Results—

Exposure to a folate-deficient diet for 3 months conferred ≈6- to 10-fold higher plasma homocysteine levels than those associated with a normal diet. Cerebral lesion volumes and neurological deficits after MCA occlusion and 72-hour reperfusion were significantly 2.1-fold increased in folate-deficient 129/SV wild-type mice compared with those associated with a normal diet, which could not be explained by obvious differences in physiological parameters. Abasic sites, hallmarks of oxidative DNA damage, were significantly increased in DNA from the ischemic brain of folate-deficient animals at early time points after MCA occlusion. Folate deficiency further increased brain lesion size in animals lacking uracil-DNA glycosylase compared with wild-type littermate mice.

Conclusions—

Folate deficiency and resultant hyperhomocysteinemia are not only associated with increased stroke risk but increase oxidative DNA damage and ischemic lesion size after MCA occlusion/reperfusion.
The Relation between the North Atlantic Oscillation and SSTs in the North Atlantic Basin
Authors: Wang Weile , Anderson Bruce T. , Kaufmann Robert K. , Myneni Ranga B.
Published: December 2004

The authors use the notion of Granger causality to investigate the relationship between the North Atlantic Oscillation (NAO) index and the sea surface temperatures (SSTs) over the Northern Hemisphere. The Granger causality analysis ensures that any apparent oceanic influence upon the atmosphere (as measured by the NAO) is provided by the ocean and is not related to preexisting conditions within the NAO itself (and vice versa when looking at the atmospheric influence upon the ocean). Although this statistical technique does not imply physical forcing of one field on the other, it is generally more reliable compared to the simple lead/lagged correlation. Using this technique, the authors find that on seasonal time scales, the preceding NAO anomalies' influence on the wintertime SST field is rather restricted. Conversely, preceding SST anomalies have a statistically significant causal effect on the wintertime NAO. However, the causal relation between preceding SSTs and the wintertime NAO is limited to the Gulf Stream extension; in contrast to the canonical tripole SST pattern typically associated with the NAO, the authors do not find that SST anomalies in either the Greenland or subtropical regions have a significant causal effect on the NAO. These results suggest that the Gulf Stream SSTs have an important influence in initiating disturbances of the atmospheric circulation over the wintertime North Atlantic.
Downward Coupling between the Stratosphere and Troposphere: The Relative Roles of Wave and Zonal Mean Processes*
Authors: Perlwitz Judith , Harnik Nili
Published: December 2004

Wave and zonal mean features of the downward dynamic coupling between the stratosphere and troposphere are compared by applying a time-lagged singular value decomposition analysis to Northern Hemisphere height fields decomposed into zonal mean and its deviations. It is found that both zonal and wave components contribute to the downward interaction, with zonal wave 1 (due to reflection) dominating on the short time scale (up to 12 days) and the zonal mean (due to wave–mean-flow interaction) dominating on the longer time scale. It is further shown that the two processes dominate during different years, depending on the state of the stratosphere. Winters characterized by a basic state that is reflective for wave 1 show a strong relationship between stratospheric and tropospheric wave-1 fields when the stratosphere is leading and show no significant correlations in the zonal mean fields. On the other hand, winters characterized by a stratospheric state that does not reflect waves show a strong relationship only between stratospheric and tropospheric zonal mean fields. This study suggests that there are two types of stratospheric winter states, characterized by different downward dynamic interaction. In one state, most of the wave activity gets deposited in the stratosphere, resulting in strong wave–mean-flow interaction, while in the other state, wave activity is reflected back down to the troposphere, primarily affecting the structure of tropospheric planetary waves.
Study of direct oxygen transfer in a submerged culture
Authors: Sobotka M. , Votruba J. , Prokop A.
Published: December 2004

Auf der Basis der Flotationstheorie der festen Partikel wurde in der Submerskultur der Mechanismus des direkten Sauerstoffübergangs in die Zelle unter den Bedingungen gegenseitiger Beeinflussung des Mikroorganismus mit der gasförmigen und der flüssigen Phase quantifiziert.
Bestimmung der Methanol‐Konzentration im stationären Zustand mit einer biologischen Methode
Authors: Nyeste L. , Kirchknopf L. , Báthory J. , Holló J.
Published: December 2004

On the base of measuring the respiration rate (HARRISON) a biological measuring method for determination of methanol concentration in stationary range was worked out. The method allows the determination of methanol concentrations up to 0.3 mg l−1 and is applicable for such cases, when microorganisms consume this substrate quickly (within a few minutes). If the methanol concentration in stationary range is known, it is possible to calculate the kinetic constants of the system.
Improved brewing of millet beer – (OYOKPO) and production of single cell proteins from the spent grain
Authors: Nkanga E. I. , Uraih N.
Published: December 2004

The improved method for preparing Oyokpo a Nigerian fermented beverage from millet, and the preparation of single cell proteins from the spent grain is described. Improvement of the brew was made by controlled malting, mashing and brewing with a pure culture of Saccharomyces cerevisiae. It had a reducing sugar content of 19.73 g/100 ml before fermentation and after fermentation 5.56% alcohol, 0.58 g/100 ml titratable acidity as acetic acid, a final pH of 4.2 and consisted of a yellowish clear liquid, slightly sour. The native brew had a reducing sugar content of 7.37 g/100 ml before fermentation and after fermentation, 2.40% alcohol, 0.43 g/100 ml titratable acidity, a final pH of 3.8 and consisted of a creamy yellowish liquid with a very sour taste. Fermented spent grain gave a higher protein yield compared to unfermented or ground millet. The lipids, proteins and crude fibre were 4.94%, 11.20% and 4.33% respectively for ground millet, 12,79%, 23.77% and 19.46% respectively for unfermented spent grain and 19.61%, 47.28% and 32.09% respectively for fermented spent grain. The high protein and fibre content of the fermented spent grain points to its potential as a feed supplement for ruminants.
Das Autoselect‐System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. V. Achtfach‐Pipettierautomat
Authors: Steininger H. , Schicht G. , Peissker M. , Knöll H.
Published: December 2004

An automatic eightfold‐pipetter has been developed with the same basic unit as the diluter of the Autoselect‐system. The pipetter is fitted with eight pipettes on a bridge over the basic unit. By means of the pipettes a volume of 0.05 ml from eight tubes is exhauseted and delivered in the holes of a test plate. Both the test plate and a cassette with 64 tubes are located on a moving carriage. the test plate on the first floor and the cassette on the ground floor. If the pipettes transfer the samples from the tubes to the holes the distance between the pipettes must be changed by a special device from 20 to 30 mm, because the distance between the holes on the test plate differs from that of the tubes.

For the transfer of 64 samples 2 minutes only are needed.
Das Autoselect‐System – ein Automatensystem zur Selektion von Antibiotikaproduzenten. VI. Achtfach‐Stanzautomat
Authors: Schicht G. , Steininger H. , Grosse P. , Knöll H.
Published: December 2004

An eightfold punch belonging to the Aùtoselect‐system is described. It is provided for the preparation of bioassay plates. From the agar of large quadratic test plates moving automatically on a carriage of the machine, 64 holes are made by eight punches. The punches arranged in a row over the test plate are lowered, if the carriage stops, and so they cut out and exhaust agar discs in a pattern of 8 × 8.
The role of mechanical shear and cavitation on the behaviour of molds
Authors: Placek J. , Ujcová E. , Musílková M. , Seichert L. , Fencl Z.
Published: December 2004

The morphology of filamentous microorganisms does essentially affect the production of metabolites. Agitating conditions may affect the morphology and for this reason the production of metabolites too.

The following parameters it was found to have an influence:

Reynolds mixing number

impeller blade tips velocity

mean shear stress close to the impeller

impeller power consumption per unit volume

cavitation pressure drop

It were presumed three mechanisms for the mechanical effect on the microorganisms:

the direct impact of the impeller blades on the microorganisms‐collision

the shear stress in the liquid phase

a sharp pressure decrease behind the impeller blades‐cavitation

Mathematical relationships are developed for the different mechanisms.Using Aspergillus niger it is shown what morphological and physiological states of this microorganism are caused by mechanical straining and the conditions for the maximal production of citric acid are studied.

Requirements for scale‐up are discussed.
Ethanol production from non‐grain feedstocks
Authors: Michaels St. L. , Blanch H. W.
Published: December 2004

A general view of the possibilities of producing ethanol from sugar, starch and cellulose feedstocks is given.

For the 3 variants net energy analysis of ethanol production and evaluation of costs are presented. With the exception of the case using molasses as feedstock the net energy balances are positive.

The greatest possible net energy yield can be expected with sugar cane followed by sugar beets, wood and paper waste. Based on feedstock availability, net energy utilization and production costs, the most promising processes for producing ethanol from non‐grain feedstocks over the next 20 years will be those processes using fermentable sugars available from nongrain starchy materials, cellulosics and whey.

The feedstock prices for cellulosics are low and if the developments in cellulose hydrolysis will lead to improve the ethanol yields from cellulose fermentation to nearer 90 percent of the theoretical value, cellulosic materials can become a good feedstock for ethanol production.