bluuebunny/crossref_metadata_2025 huggingface dataset:
Total HCV core antigen assay: A new marker of hepatitis C viremia for monitoring the progress of therapy
Authors: Zanetti Alessandro R. , Romanò Luisa , Brunetto Maurizia , Colombo Massimo , Bellati Giorgio , Tackney Charles
Published: March 2003

The ability of the total hepatitis C virus (HCV) core antigen assay was evaluated for monitoring the therapeutic responses of HCV‐infected patients treated with interferon. The ability to detect and quantitate an independent structural protein component of HCV, in the presence of circulating antibodies, makes this assay a valuable new tool in diagnosis and treatment monitoring. Measurement of total core antigen showed a strong dynamic correlation with HCV RNA data and may serve as an alternative direct marker of viral infection. In addition, with the advent of additional treatment protocols, a rapid, reliable assay for changes in HCV load may permit more frequent patient assessment and tailoring of the therapeutic regimen. J. Med. Virol. 70: 27–30, 2003. © 2003 Wiley‐Liss, Inc.
Assessment of iatrogenic transmission of HCV in southern italy: Was the cause the salk polio vaccination?
Authors: Montella Maurizio , Crispo Anna , Grimaldi Maria , Tridente Vincenzo , Fusco Mario
Published: March 2003

Since the first studies on hepatitis C virus (HCV) prevalence were published, it has been evident that southern Italy is an area of hyperendemicity. A recent study conducted in southern Italy suggested that the high prevalence of HCV infection might be the result of past iatrogenic transmission. Polio vaccination with the parenteral Salk vaccine between 1956 and 1965 by multiple use of unsafe glass syringes may have been one of the major causes of the spread of HCV infection among southern Italian adults who are now older than 40 years of age. Persons born between the 1940s and early 1960s have a nearly 3‐fold increased risk of HCV seropositivity than the younger age group. The findings are consistent with a cohort effect of exposure to the Salk parenteral vaccination. J. Med. Virol. 70: 49–50, 2003. © 2003 Wiley‐Liss, Inc.
Evidence for a mid‐Pleistocene shift of ice‐drift pattern in the Nordic seas
Authors: Helmke Jan P. , Bauch Henning A. , Mazaud Alain
Published: March 2003

Sediment proxy records from a continuous, 1.5 million year long deep‐sea sediment core from a site in the western Norwegian Sea were used to obtain new insights into the nature of palaeoceanographic change in the northern North Atlantic (Nordic seas) during the climatic shift of the Mid‐Pleistocene Revolution (MPR). Red‐green sediment colour and magnetic susceptibility records both reveal significant differences in their mean values when comparing the intervals older than 700 000 yr (700 ka) with those from the past 500 kyr. The timing and duration of these changes indicates that the MPR in the Nordic seas is characterised by a gradual transition lasting about 200 kyr. Together with further sedimentological evidence this suggests that the mid‐Pleistocene climate shift was accompanied by a general change in ice‐drift pattern. It is further proposed that prior to the onset of the major late Pleistocene glaciations in the Northern Hemisphere a significant proportion of the ice in the eastern Nordic seas originated from a southern provenance, whereas later it dominantly came from the surrounding landmasses. Copyright © 2003 John Wiley & Sons, Ltd.
Ultraviolet and visible Raman spectroscopic investigations of nanocrystalline carbon thin films grown by bias‐assisted hot‐filament chemical vapor deposition
Authors: Gupta S. , Weiner B. R. , Nelson W. H. , Morell G.
Published: March 2003

The structural bonding in a series of nanocrystalline carbon thin films grown under different substrate biasing conditions was analyzed using Raman spectroscopy in both the visible and ultraviolet (uv) regimes of the spectrum. The nanocrystalline carbon thin films studied were deposited by the hot‐filament chemical vapor deposition (HFCVD) technique using a 2% concentration of methane in hydrogen. The films were deposited on molybdenum substrates under various substrate biasing conditions. A positive bias (forward) produced a continuous flow of electrons from the filament on to the substrate, whereas a negative bias (negative) caused the substrate to be bombarded with positive ions. Films were also grown under no bias, for comparison. Differences in the Raman spectra obtained with visible (λL = 514.5 nm) and uv (λL = 244.0 nm) excitation sources were investigated. Apart from the basic features consisting of D and G bands at around 1360 and 1580 cm−1 in the case of visible Raman spectra, an extra feature at around 1060 cm−1, denoted a T band, appeared in the uv Raman spectra only. Hence, uv Raman scattering measurements clearly revealed the presence of sp3‐bonded carbon atoms. The position and its intensity ratio with respect to the G peak [(I(T)/I(G)] were used to provide a reliable means to measure the sp3 C bonding fraction, which is both semi‐quantitative and non‐destructive. The sp3 content estimated within the microstructure of n‐C thin films was found to be around 60–80%. Further, probing the samples with two different photons (visible and uv) allowed us to estimate qualitatively the amount and clustering of sp2 sites. This technique provided a fast and reliable microstructural characterization of disordered carbons. The dispersion in the Raman features is specific to each carbon system and, therefore, can be used as a fingerprint. These findings point at the similarities of bias‐assisted HFCVD nanocrystalline carbon (n‐C) materials and the tetrahedrally bonded amorphous carbon (ta‐C) materials grown by ion‐beam assisted deposition (IBAD). Copyright © 2003 John Wiley & Sons, Ltd.
Koebnerization of reactive perforating collagenosis induced by laser hair removal
Authors: Doshi Seema N. , Levy Moise L. , Markus Ramsey
Published: March 2003

Laser hair removal, due to demonstrated efficacy and safety, has become a commonly performed office procedure. We report an unusual occurrence after laser hair removal with the 800 nm diode laser that previously has never been described. After laser hair removal treatment to the ventral surface of the ears, a patient developed lesions of previously diagnosed reactive perforating collagenosis. Interestingly, the lesions appeared on the dorsal surface of the ears. Perhaps the koebner phenomenon was invoked as the laser energy penetrated to the untreated dorsal surface, which was not protected by epidermal contact cooling. Lasers Surg. Med. 32:177–179, 2003. © 2003 Wiley‐Liss, Inc.
Effective embeddings into strong degree structures
Authors: McNicholl Timothy H.
Published: March 2003

We show that any partial order with a Σ3 enumeration can be effectively embedded into any partial order obtained by imposing a strong reducibility such as ≤tt on the c. e. sets. As a consequence, we obtain that the partial orders that result from imposing a strong reducibility on the sets in a level of the Ershov hiearchy below ω + 1 are co‐embeddable.
Novel Aliphatic Polyesters Based on Functional Cyclic (Di)Esters
Authors: Lou Xudong , Detrembleur Christophe , Jérôme Robert
Published: March 2003

Recent progress in the chemical synthesis of novel aliphatic polyesters via ring‐opening polymerization of functional cyclic (di)esters are reviewed in this article. Syntheses of these functional aliphatic polyesters are being classified into three groups according to the structure of the cyclic monomers: (i) cyclic diesters, (ii) morpholine‐2,5‐dione derivatives, and (iii) cyclic esters. Progress in the synthesis and polymerization of monomers in each category is reported with an emphasis on controlled synthesis. The recent achievements have enabled the synthesis of a variety of novel aliphatic polyesters, including hydrophilic, halogenated, and unsaturated polyesters.

Structure of the most common R‐functionalized cyclic precursors of aliphatic polyesters.

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Structure of the most common R‐functionalized cyclic precursors of aliphatic polyesters.
Inhibition of cell‐cycle effectors of proliferation in bladder tumor epithelial cells by the p75NTR tumor suppressor
Authors: Khwaja Fatima , Djakiew Daniel
Published: March 2003

The neurotrophin (NTR) receptor (p75NTR) is a cell‐surface glycoprotein that binds to the neurotrophin family of growth factors, of which the prototypic member is nerve growth factor (NGF). This receptor was previously shown to retard cell‐cycle progression by inducing accumulation of cells in G1 with a concomitant reduction of cells in the S phase of the cell cycle. Furthermore, p75NTR was shown to be an effective tumor suppressor of bladder cancer cell growth in vivo. In order to investigate the mechanism of p75NTR‐dependent suppression of cell‐cycle progression, we utilized transgenic clones of bladder tumor cells that express p75NTR in increasing concentrations to demonstrate an effect of p75NTR on the levels of cell‐cycle regulatory proteins that modulate proliferation of tumor cells. A rank‐order (dose‐dependent) increase in p75NTR protein expression was associated with a decrease in cell proliferation. This p75NTR‐dependent suppression of proliferation was rescued with NGF. In the absence of ligand, a dose‐dependent increase in p75NTR protein expression was associated with reduced expression of cyclin D1, cyclin E, and cyclin‐dependent kinase 2 (cdk2) as well as decreased cdk2 activity. There was also a decrease in the expression of hyper‐phosphorylated retinoblastoma protein, the transcription factor E2F1, and proliferating cell nuclear antigen, and there was an increase in expression of hypophosphorylated Rb and the cdk inhibitor p16Ink4a with increasing p75NTR expression. Treatment of tumor cells with NGF ameliorated these p75NTR‐dependent changes in the levels of cell‐cycle regulatory proteins and rescued the tumor cells from p75NTR‐dependent inhibition of proliferation. Hence, it can be concluded that p75NTR inhibits proliferation by altering the expression of cell‐cycle regulatory proteins and that NGF ameliorates this effect. © 2003 Wiley‐Liss, Inc.
EDFA gain flattening using phase‐shifted long‐period grating
Authors: Zhu Yinian , Shum Ping , Lu Chao , Lacquet Beatrys M. , Swart Pieter L. , Spammer Stephanus J.
Published: March 2003

A novel device using a phase‐shifted long‐period grating cascaded with one normal long‐period grating is designed to flatten the gain spectrum of EDFAs with all of three gain peaks. The experimental results show that the 3‐dB bandwidth of flattened EDFA is 46 nm, and gain peak‐to‐peak is approximately 0.9 dB. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 153–157, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10853
Real‐time changes of the local vasoactive peptide systems (angiotensin, endothelin) in the bovine corpus luteum after induced luteal regression
Authors: Schams Dieter , Berisha Bajram , Neuvians Tanja , Amselgruber Werner , Kraetzl Wolf‐Dieter
Published: March 2003

There is evidence that angiotensin II (Ang II) and endothelin‐1 (ET‐1) may interact in an additive or synergistic way during luteal regression. The aim of the study was to investigate real time changes in luteal tissue of angiotensin and endothelin system members in mRNA expression, tissue concentrations, tissue localization, and ACE (angiotensin converting enzyme) antagonist application after prostaglandin F2α (PG) induced (days 8–12) luteal regression in cow. Corpora lutea (CL) were collected by transvaginal ovaryectomy before and 2, 4, 12, 24, 48, and 64 hr (n = 5/time point) after PG injection. ACE mRNA expression (RT‐PCR) increased continuously and peaked at 12, 24 hr; ECE‐1 (endothelin converting enzyme) peaked at 12 hr, and both peptides in tissue (Ang II and ET‐1) increased significantly and peaked at 24 hr. The expression of receptors for Ang II (AT1R and AT2R) did not change in contrast to ET receptors (ETR‐A and ETR‐B), which were up‐regulated. Localization in tissue revealed very weak staining for Ang II and ET‐1 before PG application followed by a clear increase of staining predominantly in large luteal cells, but also in endothelial cells. In two experiments, the attempt was made to block ACE by the antagonist captopril with two different doses. In both experiments with captopril, progesterone levels were not significantly different from controls. Ang II alone seems to be not essential for functional luteolysis in bovine system. In conclusion, the results suggest that both Ang II and ET‐1 are in parallel up‐regulated during luteal regression and may act as vasoconstrictors during functional luteolysis, but also as apoptosis inducer during functional/structural luteolysis. Mol. Reprod. Dev. 65: 57–66, 2003. © 2003 Wiley‐Liss, Inc.
Coactivator CBP in the regulation of conceptus IFNτ gene transcription
Authors: Xu Ningchun , Takahashi Yuji , Matsuda Fuko , Sakai Senkiti , Christenson Ronald K. , Imakawa Kazuhiko
Published: March 2003

Studies of ovine interferon‐tau (oIFNτ) gene regulation, an anti‐luteolytic factor produced by conceptuses of the ruminant ungulates, have been carried out, but a definitive mechanism for its spatial‐temporal transcription has not been elucidated. Recently, specific binding regions for transcription factors AP‐1 and Ets‐2 on the oIFNτ gene were identified; however, a molecular mechanism by which these factors regulate oIFNτ gene transcription has not been characterized. In the present study, we investigated the potential relationship between AP‐1 and Ets‐2, and their association with a coactivator, cAMP‐response element binding protein‐binding protein (CBP), on oIFNτ gene transcription in a transient transfection system using human choriocarcinoma JEG3 cells. The oIFNτ gene promoter/enhancer (−654 to + 1 bases, wild type)‐luciferase reporter construct (pGL3‐654) or its mutant at the AP‐1 or Ets‐2 site was cotransfected with CBP (pRc/RSV‐CBP) construct along with c‐jun, c‐fos, and/or Ets‐2 expression plasmid. CBP enhanced transcription of the wild type oIFNτ‐reporter construct; however, this coactivator had no effect on the oIFNτ‐reporter construct with mutated AP‐1 or Ets‐2 site. Cotransfection of CBP with c‐jun and/or Ets‐2, but not with c‐fos, further increased oIFNτ gene transactivation although amounts of c‐jun and c‐fos expression, resulting from expression vectors, were similar. In addition, CBP inhibitor adenovirus 12S E1A (E1A), but not the mutant of E1A without CBP binding domain (Δ2‐36), suppressed oIFNτ gene transcription. These observations suggest that c‐jun and Ets‐2 are the most probable binding partners for CBP in the potentiation of oIFNτ gene transcription. Mol. Reprod. Dev. 65: 23–29, 2003. © 2003 Wiley‐Liss, Inc.
Inflammatory myopathies: Clinical, diagnostic and therapeutic aspects
Authors: Mastaglia Frank L. , Garlepp Michael J. , Phillips Beverley A. , Zilko Paul J.
Published: March 2003

The three major forms of immune‐mediated inflammatory myopathy are dermatomyositis (DM), polymyositis (PM), and inclusion‐body myositis (IBM). They each have distinctive clinical and histopathologic features that allow the clinician to reach a specific diagnosis in most cases. Magnetic resonance imaging is sometimes helpful, particularly if the diagnosis of IBM is suspected but has not been formally evaluated. Myositis‐specific antibodies are not helpful diagnostically but may be of prognostic value; most antibodies have low sensitivity. Muscle biopsy is mandatory to confirm the diagnosis of an inflammatory myopathy and to allow unusual varieties such as eosinophilic, granulomatous, and parasitic myositis, and macrophagic myofasciitis, to be recognized. The treatment of the inflammatory myopathies remains largely empirical and relies upon the use of corticosteroids, immunosuppressive agents, and intravenous immunoglobulin, all of which have nonselective effects on the immune system. Further controlled clinical trials are required to evaluate the relative efficacy of the available therapeutic modalities particularly in combinations, and of newer immunosuppressive agents (mycophenolate mofetil and tacrolimus) and cytokine‐based therapies for the treatment of resistant cases of DM, PM, and IBM. Improved understanding of the molecular mechanisms of muscle injury in the inflammatory myopathies should lead to the development of more specific forms of immunotherapy for these conditions. Muscle Nerve 27:407–425, 2003
Dysmyelinating sensory‐motor neuropathy in merosin‐deficient congenital muscular dystrophy
Authors: Di Muzio A. , De Angelis M.V. , Di Fulvio P. , Ratti A. , Pizzuti A. , Stuppia L. , Gambi D. , Uncini A.
Published: March 2003

A 20‐year‐old man with mild myopathy, external ophthalmoparesis, epilepsy, and diffuse white matter hyperintensity in the brain on magnetic resonance imaging had partial merosin deficiency in muscle and absent merosin in the endoneurium. Motor and sensory nerve conduction velocities were slow. Nerve biopsy showed reduction of large myelinated fibers, short internodes, enlarged nodes, excessive variability of myelin thickness, tomacula, and uncompacted myelin, but no evidence of segmental demyelination, naked axons, or onion bulbs. Thus, in congenital muscular dystrophy, merosin expression may be dissociated in different tissues, and the neuropathy is sensory‐motor and due to abnormal myelinogenesis. Muscle Nerve 27:
500–506, 2003
Dysfunction at the motor end‐plate and axon membrane in Guillain–Barré syndrome: A single‐fiber EMG study
Authors: Spaans Frank , Vredeveld Jan‐Willem , Morré Humphrey H.E. , Jacobs Bart C. , De Baets Marc H.
Published: March 2003

In nine patients with Guillain‐Barré syndrome (GBS), stimulation single‐fiber electromyography (SFEMG) and serological studies were performed in the acute stage of the illness. Increased jitter and intermittent blocking of muscle fiber action potentials occurred to a varying degree in all patients. Five patients had elevated titers of antiganglioside antibodies. The most remarkable EMG phenomenon was the occurrence in all patients of impulse blocking at normal or slightly increased jitter. The assumption that this phenomenon was due to an axolemmal dysfunction was confirmed by the occurrence in two patients of concomitant blocking of two muscle fiber action potentials at strictly normal jitter values. In one patient this sign of axonal dysfunction was demonstrated with SFEMG at voluntary activation. In another patient, concomitant blocking was associated with greatly increased but completely independent jitter of both components. The results of this study show that both a disorder of neuromuscular transmission and an axolemmal dysfunction play a role in the pathophysiology of GBS. Muscle Nerve 27: 426–434, 2003
IgG from patients with Guillain–Barré syndrome interact with nicotinic acetylcholine receptor channels
Authors: Krampfl K. , Mohammadi B. , Buchwald B. , Jahn K. , Dengler R. , Toyka K.V. , Bufler J.
Published: March 2003

In Guillain–Barré syndrome (GBS), immunoglobulin G (IgG) antibodies block neuromuscular transmission pre‐ and postsynaptically and thus are of potential pathogenic relevance. We investigated whether IgG from GBS patients has a direct interaction with nicotinic acetylcholine receptor (nAChR) channels. Purified IgG fractions from six GBS patients that blocked neuromuscular transmission in a previous study were analyzed by the patch‐clamp technique in combination with an ultrafast system for solution exchange. Sera from three patients with other inflammatory neurological disorders were used as controls. Mouse myotubes expressing native embryonic‐type nAChR channels and human embryonic kidney (HEK) 293 cells transiently transfected with recombinant adult‐type nAChR channels were used. Repeated 20‐ms pulses of acetylcholine (ACh) were applied to outside‐out patches in the presence of GBS‐IgG. IgG of the patients had a significant reversible blocking action on embryonic‐ and adult‐type nAChR channels with some variability in the magnitude of the block. Activation and desensitization kinetics were not affected when GBS‐IgG was applied. None of the control sera blocked the AChR channels. The observed postsynaptic block effect fulfills the criteria of a channel‐blocking IgG antibody similar to those seen in autoimmune myasthenia and may contribute to muscle weakness during the acute phase of GBS. Muscle Nerve 27:435–441, 2003
Chronic inflammatory demyelinating polyradiculoneuropathy in diabetic patients
Authors: Haq Rizwan U. , Pendlebury William W. , Fries Timothy J. , Tandan Rup
Published: March 2003

This retrospective analysis was undertaken to determine whether a subset of diabetic patients with demyelinating polyneuropathy were similar to patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Ten patients meeting the clinical criteria for idiopathic CIDP were compared to nine patients with diabetes and demyelinating polyneuropathy. The diabetic patients with demyelinating polyneuropathy displayed clinical, electrophysiologic, and histologic features that were similar to those in CIDP patients. All six patients with diabetes and demyelinating polyneuropathy who were treated with immunomodulatory therapy showed a favorable response. Our study highlights the importance of investigating diabetic patients with polyneuropathy in an attempt to identify patients with demyelinating polyneuropathy, because of the likelihood of benefit in these patients from immunomodulatory treatment. Muscle Nerve 27: 465–470, 2003
Modelling of a snowpack in interaction with a flexible structure using a coupled Lagrangian‐discrete approach
Authors: Nicot François , Gagliardini Olivier , Boutillier Benoît
Published: March 2003

The search to improve protective techniques against natural phenomena such as snow avalanches continues to use classic methods to calculate flexible structures. This paper deals with a new method for designing avalanche protection nets; this method is based on a coupled analysis of both the net structure and the snow mantel using a coupled Lagrangian‐discrete approach. This has led to the development of computational software so that avalanche nets can be easily designed. This tool provides for the evolving forces acting on several parts of the net as a function of the snow situation. Copyright © 2003 John Wiley & Sons, Ltd.
Solving linear initial value problems by Faber polynomials
Authors: Novati P.
Published: March 2003

In this paper we use the theory of Faber polynomials for solving N‐dimensional linear initial value problems. In particular, we use Faber polynomials to approximate the evolution operator creating the so‐called exponential integrators. We also provide a consistence and convergence analysis. Some tests where we compare our methods with some Krylov exponential integrators are finally shown. Copyright © 2002 John Wiley & Sons, Ltd.
An algorithm to simulate surface creation without element deletion or remeshing
Authors: Gerken J. M. , Bennett J. G. , Smith F. W.
Published: March 2003

One of the major obstacles to modelling discrete fracture and fragmentation of materials within the finite element (FE) framework is the inability to easily model the resulting geometry changes. This paper presents an algorithm for three‐dimensional element cohesion and separation implemented in the explicit FE code DYNA3D. The algorithm handles mesh definition and solution difficulties necessary for general element separation with minimal additional effort required of the user.

The algorithm modifies the standard mesh definition so that element separation does not require remeshing. The original continuity of the structure is maintained by averaging the nodal accelerations for each coincident node set then applying this average acceleration to each of the nodes in the set. When specified failure criteria for an interface are met, averaging is no longer performed, thereby allowing the coincident nodes to separate and create new surface. The new surface can be automatically incorporated in the contact definition so that the contact of these new surfaces is modelled using the same contact considerations of the original FE model.

Following a discussion of historical and current FE fracture/fragmentation models, the general framework of the algorithm is presented. Also, results are presented which show that the algorithm simulates surface creation in a variety of simulations. Published in 2003 by John Wiley & Sons, Ltd.
Comparison between 2‐day and 10‐day MPTP treatment modalities in the mouse model of Parkinson's disease
Authors: Kim Kisok , Kim Chang Ok , Huh Youngbuhm , Ahn Byeongwoo , Han Beom Seok , Choi Kwang Sik
Published: March 2003

We employed a novel regimen of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) treatment to produce a Parkinson's disease (PD) animal model demonstrating typical Parkinsonian symptoms. In order to compare the effects of the different durations of MPTP treatment (daily intraperitoneal injections of 30 mg/kg MPTP for 2 or 10 days), the numbers and distribution patterns of tyrosine hydroxylase‐immunoreactive (TH‐ir) neurons and fibers were examined in the substantia nigral and stiatal brain regions of C57/B16 mice. The mean numbers of TH‐ir neurons in the substantia nigra were significantly lower (57.3% and 48.1%) than the numbers in the saline‐treated controls after 2 and 10 days of MPTP treatment, respectively. Furthermore, the optical density of the TH‐ir fibers in the striatum was reduced by 9.8% and 14.1% after 2‐ and 10‐day treatments, respectively. However, the reduction in numbers of TH‐ir neurons in the substantia nigra and striatum was not significantly different between the 2‐day and 10‐day treatment groups. Yet, it seems that only the 10‐day treatment regimen exceeded the threshold of motor deficits. Thus, chronic MPTP treatment appears to be required to mirror the pathophysiological characteristics of Parkinsonism.
Numerical density of pyramidal neurons in the hippocampus of 4 and 20 week old male and female rats
Authors: Kaplan S. , Rağbetli M. Ç. , Canan S. , Sahin B. , Marangoz C.
Published: March 2003

A study designed to investigate how the cellular laterality in rosto‐caudal direction changes due to age and sex was presented. It is a well‐known fact that asymmetry is an important issue in understanding brain functions. Frontal sections of 5 µm thickness with 200 µm intervals were taken from both dorsal hippocampi of 4‐ and 20‐week‐old male and female rats. Sections were stained with hematoxylin‐eosin and the levels of sections were determined according to a stereotaxic atlas. In each level, numerical density of pyramidal cells of the right and left area CA1, CA3 and CA4 of dorsal hippocampi were estimated by means of counting pyramidal cells under 10 × 40 magnification. Numerical cell density obtained from the right and left dorsal hippocampi of male and female rats were compared. Results are as follows: 1) Numerical cell density in the left and right dorsal hippocampi of 20‐week female rats was not high than 4‐week female dorsal hippocampi (p>0.05). 2) Difference between 4‐week old female and male dorsal hippocampi of right and left CA1, CA3 and CA4 areas were not raised a significant level (p>0.05). Differences between 20‐week‐old group of male and female rats with the exception of female CA4 area were not also significant. 3) Right and left dorsal hippocampi CA4 areas of the 20‐week‐old group showed a higher numerical density than the same area of the 4‐week‐old group (p<0.007). This difference may show a postnatal neurogenesis in area CA4. The results, which are summarized above, may be helpful in understanding the mechanisms of human brains.
Wirkstoffe und Wirkprinzipien: Angriffspunkt Ergosterolbiosynthese
Authors: Bracher Franz
Published: March 2003

Die Ergosterolbiosynthese ist die „Achillesferse”︁ von Pilzen und Hefen. Drei wichtige Klassen von Antimykotika sind Inhibitoren unterschiedlicher Enzyme der Ergosterolbiosynthese: Die Azole als Inhibitoren der Lanosterol‐14α‐demethylase sind die größte und umsatzstärkste Klasse. Diese Breitspektrum‐Antimykotika haben jedoch auf Grund ihrer Interaktion mit Häm‐abhängigen Enzymen bei systemischer Gabe ein hohes Interaktionspotenzial. Die Allylamine hemmen selektiv die Squalenepoxidase von Pilzen, das Morpholin Amorolfin hemmt mit der Δ14‐Reduktase und der Δ8, Δ7‐Isomerase zwei verschiedene Enzyme der Ergosterolbiosynthese.

Durch Analyse des Sterolmusters eines Modellkeims nach Inkubation mit Inhibitoren lassen sich die Zielenzyme eindeutig identifizieren.
Neue Antimykotika: Ein Silberstreif am Horizont
Authors: Schäfer‐Korting Monika , Holzgrabe Ulrike
Published: March 2003

In der nahen bzw. mittleren Zukunft ist die Zulassung weiterer Azole der 2. Generation sowie von weiteren Glucansynthase‐Inhibitoren zu erwarten. Auch Inhibitoren der Chitinsynthese sind Gegenstand der aktuellen Antimykotikaentwicklung.
Congenital limb deficiencies in newborn infants: prevalence, characteristics and prenatal diagnosis
Authors: Makhoul I. R. , Goldstein I. , Smolkin T. , Avrahami R. , Sujov Polo
Published: March 2003

Congenital limb deficiency (CLD) occurs in 0.54 to 0.59/1000 live‐born infants and varies according to its anatomic location, type and cause. Our aim was to present a fetus with a prenatal ultrasonographic diagnosis of CLD (transverse reduction deficiency of the left upper limb), and to determine the prevalence and clinical characteristics of CLD at a tertiary medical centre in Israel. Among 78 500 live‐born infants, there were 24 cases of CLD (0.31/1000): 45.8% of the CLD cases with affected upper limbs, 45.8% with affected lower limbs, and 8.4% with both limbs affected; 88.4% of the limb deficiencies were longitudinal and 11.6% were transverse; and, 33.3% (8/24) of the affected newborn infants had additional congenital anomalies. We conclude that CLD is not an infrequent finding in live‐born infants. Comprehensive ultrasonography of the fetus allows early prenatal diagnosis of CLD and provides the parents with important information and helps them in their decision regarding the fate of the pregnancy. Copyright © 2003 John Wiley & Sons, Ltd.
Bose‐Einstein‐Kondensation mit Cäsium
Authors: Weber Tino , Herbig Jens , Mark Michael , Nägerl Hanns‐Christoph
Published: March 2003

Seit der ersten Erzeugung eines Bose‐Einstein‐Kondensates (BEC) vor einigen Jahren konnten nur wenige weitere atomare Spezies in diesen Materiezustand versetzt werden. Physikern an der Universität Innsbruck ist dies nun erstmals mit Cäsium gelungen [1]. Cäsium zeigt ein exotisches Wechselwirkungsverhalten, das neuartige Experimente in Kondensaten ermöglicht.
Coole Eisenräder
Authors: Waldmann Oliver
Published: March 2003

Kühlen durch adiabatisches Entmagnetisieren ist eine klassische Methode, um Temperaturen von wenigen Millikelvin zu erreichen. In kleinen, ringförmigen magnetischen Molekülen, so genannten Eisenrädern, beobachteten Physiker an der Universität Erlangen‐Nürnberg auch den umgekehrten Effekt: Abkühlung durch Erhöhen des Magnetfeldes. Dies ermöglicht neue Einblicke in die Physik molekularer Nanomagnete [1].
Antike Gläser und versteinertes Elfenbein: Röntgenanalyse in der Kunst
Authors: Reiche Ina , Radtke Martin , Brouder Christian
Published: March 2003

Physikalische Methoden der Archäometrie liefern den Kunsthistorikern und Archäologen wichtige Informationen. Materialspezifische Größen geben Aufschluss über Alter, Authentizität, Herkunft und Herstellungstechniken sowie Alterserscheinungen von Gegenständen. Insbesondere die Röntgenanalyse hat in jüngster Zeit wertvolle Beiträge hierzu geliefert. Dabei spannt sich ein weiter Bogen von den Mysterien ägyptischer Augenschminke über die Herstellungstechnik römischer Gläser bis zur Authentizitätsuntersuchung mittelalterlicher Silberstiftzeichnungen.
On the theory of radical depolymerization: A rigorous solution
Authors: Yashin V. V. , Isayev A. I.
Published: March 2003

A rigorous solution to a model of radical depolymerization is presented. The model includes random chain scission, depropagation, radical transfer, and first‐order radical termination. The evolution of the molecular weight distribution in the course of depolymerization has been determined under the condition that the initial polymer is characterized by Flory's distribution. The kinetic equations consider the presence of chains with two radicalized ends, which are usually neglected. The commonly used simplifying assumption of the steady‐state radical concentration is not employed, and this makes the obtained results valid at any ratios between the rate constants. The predictions of the steady‐state approximation are compared to those of the rigorous approach in the case of depolymerization accompanied by volatilization of monomeric species. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 965–982, 2003
Quantitative theory of living free‐radical polymerization. III. Calculation of copolymerization products' spinodal
Authors: Zharnikov Timur , Yakovlev Alexander , Kuchanov Semion
Published: March 2003

The problem of finding conditions of the loss of thermodynamic stability by the reaction system was solved on the basis of the developed theory of living free‐radical copolymerization. The spinodal's calculations were carried out for a significant number of systems differing in the values of kinetic, stoichiometric, and thermodynamic parameters. Analysis of the results of such calculations revealed some regularities in the spinodal curves' behavior and permitted us to classify their possible topological types. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 892–902, 2003
Combinatorial investigations of interfacial failure
Authors: Crosby Alfred J. , Karim Alamgir , Amis Eric J.
Published: March 2003

Conventional measurements of interfacial strength focus on a single variable, whereas many variables couple nontrivially and simultaneously to define this property. We present a combinatorial methodology that allows the effects of multivariable environments on interfacial strength to be investigated in a high‐throughput, parallel, and quantitative manner. This technique is largely based on the theory of Johnson, Kendall, and Roberts that quantifies adhesion through the contact and separation of a spherical lens and flat substrate. For our experiments, we fabricated a combinatorial library consisting of a two‐dimensional array of spherical caps and a complementary substrate. The array of spherical caps was brought into contact and subsequently separated from the substrate, whereas the relative displacement and contact area of the individual lenses were recorded. With gradient library‐fabrication methods, two adhesion‐controlling parameters can be continuously varied along the orthogonal axes of the array. In this manner, each lens quantifies the interfacial strength at a unique point in parameter space. We demonstrate this multilens contact‐adhesion test by measuring the effect of temperature and coating thickness on the self‐adhesion of polystyrene thin films. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 883–891, 2003
The periglacial record of Holocene environmental change, subantarctic Marion Island
Authors: Holness S. D.
Published: March 2003

This paper examines the evidence for cold‐climate conditions on Marion Island, both present and past, and discusses the palaeoenvironmental implications. Under present conditions frost penetration, except in the highest‐altitude areas, is limited to the upper 0.05–0.3 m of the soil. Relict periglacial features include large stone‐banked lobes and terraces, vegetation‐banked features and blockstreams. It is suggested that these features are the result of deep seasonal frost. Copyright © 2003 John Wiley & Sons, Ltd.
The impact of solar radiation upon rock weathering at low temperature: a laboratory study
Authors: Zhu Li‐ping , Wang Jia‐cheng , Li Bing‐yuan
Published: March 2003

The impact of solar radiation heating upon rock temperatures in a cold environment was investigated by an experimental simulation. Different rock samples, collected from the central part of the Tibet Plateau, were pre‐treated and put in a low‐temperature box. Temperatures in the box changed by a radiation heat source that simulated solar insolation. Results show that the temperature‐increase rate of samples saturated by water is similar to that saturated by salt solution, but the decrease rate of the former is higher than the latter. The temperature rebound derived from the potential heat release of the rock‐interstitial water transition at −4° C occurred more frequently on samples saturated by water than upon those saturated by salt solution. Salt content is a possible agent that inhibits the freeze‐thaw process. Insolation heating induces faster temperature variations on the rock surface than in the interior. This is more closely related to rock mineral composition than to pore size and pore density. This implies that fast temperature variations may lead to the continuous expanding and contraction of the rock minerals. This may result in rock fatigue and may dominate the weathering process. These results, applied to different rocks saturated by water or salt solution, are also supported by measuring changes in ultrasonic‐wave‐transmitting rates. Copyright © 2003 John Wiley & Sons, Ltd.
Quantum measurement and information
Authors: Hradil Z. , Řeháček J.
Published: March 2003

The operationally defined invariant information introduced by Brukner and Zeilinger is related to the problem of estimation of quantum states. It quantifies how the estimated states differ in average from the true states in the sense of Hilbert‐Schmidt norm. This information evaluates the quality of the measurement and data treatment adopted. Its ultimate limitation is given by the trace of inverse of Fisher information matrix.
Stability of quantum spins in a magnetic field
Authors: Burić N.
Published: March 2003

Continuous representations of the dynamical $SU(2)$ group, and the corresponding generalized coherent states, are used to conjugate dynamics of a system of quantum spins to that of a classical Hamiltonian system. Stability of the Hamiltonian system obtained are studied, using linear stability analyses and results from the perturbation theory. Quantum evolution of any of the compound‐spins components is described exactly by classical Hamilton's equations. No semiclassical asymptotics in the analyses or explicit time‐dependence has been involved.
Application of the multicomponent Falicov–Kimball model to intermediate‐valence materials: YbInCu4 and EuNi2(Si1–xGex)2
Authors: Freericks J. K. , Zlatić V.
Published: March 2003

We develop a formalism to solve the multicomponent Falicov–Kimball model with dynamical mean‐field theory, allowing for all possible crystal‐field couplings (including spin‐orbit coupling). We apply these techniques to solve models of the intermediate‐valence transition [as seen in YbInCu4 and EuNi2(Si1–xGex)2] in the simple limit of no crystal field or spin‐orbit coupling. We show results for the uniform spin susceptibility, the average localized electron concentration, and transport properties. We also investigate the metamagnetic transition.
Ab initio theory of exchange interactions in itinerant magnets
Authors: Turek I. , Kudrnovský J. , Drchal V. , Bruno P. , Blügel S.
Published: March 2003

The paper reviews an ab initio two‐step procedure to determine thermodynamic properties of itinerant magnets. In the first step, the selfconsistent electronic structure of a system is calculated using the tight‐binding linear muffin‐tin orbital method combined with Green function techniques. In the second step, the parameters of the effective classical Heisenberg Hamiltonian are determined using the magnetic force theorem and they are employed in subsequent evaluation of magnon spectra, the spin‐wave stiffness constants and the Curie/Néel temperatures. Applicability of the developed scheme is illustrated by investigations of selected properties of 3d metals Fe, Co, and Ni, diluted magnetic semiconductors (Ga,Mn)As, and 4f metals Gd and Eu.
Competition between superconductivity and the pseudogap phase in the t–J model
Authors: Zeyher R. , Greco A.
Published: March 2003

The t–J model in the large N limit (N denotes the number of spin components) yields a pseudogap phase in the underdoped region which is related to a d‐wave charge density wave (d‐CDW). We present results for the doping dependence of the superconducting and d‐CDW order parameters as well as for collective excitations in the presence of these two order parameters. We argue that the electronic Raman spectrum with B1g symmetry probes the amplitude fluctuations of the d‐CDW at zero momentum.
Coherent electronic transport through magnetic junction
Authors: Lipiński S. , Bułka B. R. , Babiaczyk W.
Published: March 2003

A quantum dot with a single energy level coupled to ferromagnetic electrodes is considered within the slave boson approach. Magnetic polarisation of the leads induces the spin accumulation at the dot. Its maximum occurs in the mixed valence range and decreases to zero in the Kondo regime. We have calculated the conductance for parallel and antiparallel orientations of polarisation of electrodes. Magnetoresistance takes the largest values in the empty state regime, considerably decreases in mixed valence range and reaches the smallest values in the Kondo regime, where in some cases even negative magnetoresistance can occur.
Separation of quadrupole and magnetic mechanismsof 209Bi nuclear spin–lattice relaxation in Bi4Ge3O12
Authors: Morozova E. N. , Gippius A. A. , Khozeev D. F. , Orlov V. G. , Shlikov M. P. , Baenitz M.
Published: March 2003

Bi4Ge3O12 belongs to the class of complex Bi‐oxides (α‐Bi2O3, Bi3O4Br) which exhibits unusual magnetic properties. Local magnetic fields of about 30 G were revealed in the Bi4Ge3O12 single crystal by 209Bi NQR experiments. In the present paper the nuclear spin–lattice relaxation was studied in the Bi4Ge3O12 single crystal by 209Bi NQR spin–echo technique. The experimental relaxation curves were described by the single effective spin–lattice relaxation time T1. The temperature dependence of 1/T1 was close to Tn law with n = 2.4 – 2.7. The nuclear spin–lattice relaxation in the multi‐level system was theoretically calculated for the case of single‐axial crystalline electric field. Both quadrupole and magnetic mechanisms of relaxation were taken into account. We conclude that the magnetic mechanism contributes noticeably to the spin–lattice relaxation in Bi4Ge3O12 at T ≤ 50 K.
Oxygen‐isotope effect on the magnetic properties of Pr0.7Ca0.3MnO3 under strong pulsed magnetic fields
Authors: Fedorov G. E. , Babushkina N. A. , Inyushkin A. V. , Taldenkov A. N.
Published: March 2003

Magnetization and susceptibility measurements have been performed on oxygen‐isotope substituted (16O and 18O) samples of Pr0.7Ca0.3MnO3 under pulsed magnetic fields up to 35 T. Experiments were carried out within the temperature range 78 to 300 K. Magnetic‐field‐induced phase transition into ferromagnetic state has been obtained in both samples at temperatures up to 200 K. Isotope substitution has been proved to have a significant impact on the temperature and field of this transition. Phase diagrams of the samples obtained from magnetization measurements are presented.
Dielectric breakdown strength in magnetic fluids
Authors: Kopčanský P. , Tomčo L. , Marton K. , Koneracká M. , Potočová I. , Timko M. , Jadzyn J. , Czechowski G.
Published: March 2003

The application of an external magnetic field on the magnetic fluids induces needle like structuralization of magnetic particles. The influence of this aggregation of magnetic particles in an external magnetic field H on the magneto‐dielectric behaviour and dielectric breakdown strength of a transformer oil based magnetic fluids was measured. The observed decrease of dielectric breakdown strength (for H = 0 and H ⟂ E vs. distance between electrodes is found to be in agreement with a theory of semi‐classical bond percolation for a non‐linear composite material. In situation when E ‖ H oscillations of dielectric breakdown strength were observed that are associated with a size effect probably.
The ground state for Ising model ±J on the tube
Authors: Błaszyk M.
Published: March 2003

The Ising model with exchange integrals ±J for a square lattice spanned over infinite length tubes of the width of 2, 3, or 4 bonds is considered. The paper gives a short description of a method of linear equations allowing a reduction of a physical problem of determination of e.g. energy, entropy, magnetisation for systems with frozen disorder, to a solution of a system of linear equations. The results for energy, entropy and magnetisation possible for a short presentation are given.
Dynamical CPA theory of magnetism – harmonic approximation
Authors: Kakehashi Y.
Published: March 2003

We have developed the dynamical coherent potential approximation (CPA) to the correlated electron system on the basis of the functional integral method and the harmonic approximation. The theory becomes exact in the high temperature limit, reproduces the results of the second order perturbation theory for small Coulomb interaction, and takes into account the terms to describe the strong correlation limit. The numerical calculations show that the theory describes the Curie–Weiss susceptibility, a large reduction of the Curie temperature due to the dynamical effects, and a many‐body satellite peak as well as a band narrowing in the density of states.
The correlated Kondo‐lattice model
Authors: Kienert J. , Santos C. , Nolting W.
Published: March 2003

We investigate the ferromagnetic Kondo‐lattice model (FKLM) with a correlated conduction band. A moment conserving approach is proposed to determine the electronic self‐energy. Mapping the interaction onto an effective Heisenberg model we calculate the ordering of the localized spin system self‐consistently. Quasiparticle densities of states (QDOS) and the Curie temperature TC are calculated. The band interaction leads to an upper Hubbard peak and modifies the magnetic stability of the FKLM.
Effect of local environment on the magnetic properties of the (Cu1–xCox)2MnSn alloy
Authors: Pugaczowa‐Michalska M.
Published: March 2003

The electronic structure and the ground state properties of the quaternary Heusler alloy (Cu1–xCox)2MnSn have been studied using the TB‐LMTO method. The self‐consistent band structure calculations were performed for experimental lattice parameter. The (Cu1–xCox)2MnSn system has been calculated for the supercell structure and for the following value of the parameter x: 0, 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875, 1.0. The magnetic properties are in agreement with experimental data. In particular the observed increase of total magnetic moment with concentration of Co is reproduced by our calculations. We present the value of local magnetic moment of the Co and Cu atoms for various possible configurations. The dependence of magnetic moment on the local environment has been studied for all concentrations.
Transparent interface between classical molecular dynamics and first‐principles molecular dynamics
Authors: Du Mao‐Hua , Cheng Hai‐Ping
Published: March 2003

A distinctive approach that combines first‐principles Born–Oppenheimer local spin density molecular dynamics (BO‐LSD‐MD) with classical molecular dynamics is formulated, developed, and implemented to study silicon dioxide. Compared with previous hybrid schemes, our Hamiltonian is constructed to optimize the description of local chemistry in the center of the quantum region and mechanical properties at the quantum–classical boundary. With this method, the interface between the quantum and classical regions reflects faithfully the interatomic forces derived from quantum and classical descriptions, respectively. Ground‐state structures obtained using our hybrid approach are compared with those calculated via quantum and classical methods. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003