bluuebunny/crossref_metadata_2025 huggingface dataset:
Catastrophizing and internal pain control as mediators of outcome in the multidisciplinary treatment of chronic low back pain
Authors: Spinhoven Philip , ter Kuile Moniek , Kole‐Snijders Ank M.J , Mansfeld Menno Hutten , den Ouden Dirk‐Jan , Vlaeyen Johan W.S
Published: November 2003

The aim of the present study was to examine (a) whether a cognitive‐behavioral treatment (differentially) affects pain coping and cognition; and (b) whether changes in pain coping and cognition during treatment mediate treatment outcome. Participants in this randomized clinical trial were 148 patients with chronic low back pain attending a multidisciplinary treatment program consisting of operant‐behavioral treatment plus cognitive coping skills training (N=59) or group discussion (N=58) or allocated to a waiting list control condition (N=31). Patients improved with respect to level of depression, pain behavior and activity tolerance at posttreatment and 12‐month follow‐up. Treatment also resulted in a short‐ and long‐term decrease in catastrophizing and an enhancement of internal pain control. Changes in catastrophizing and to a lesser degree in internal pain control mediated the reduction in level of depression and pain behavior following treatment. The use of behavioral and cognitive interventions aimed at decreasing catastrophizing thoughts about the consequences of pain and promoting internal expectations of pain control possibly constitute an important avenue of change irrespective of the type of treatment.
A polymorphic locus in the intron 16 of the human angiotensin‐converting enzyme (ACE) gene is not correlated with complex regional pain syndrome I (CRPS I)
Authors: Hühne K. , Leis S. , Schmelz M. , Rautenstrauss B. , Birklein F.
Published: November 2003

Exaggerated neurogenic inflammation has been recognized to be one reason for many CRPS symptoms. Since angiotensin‐converting enzyme (ACE) is a key enzyme for the termination of neurogenic inflammation, it has been selected as a candidate gene for CRPS predisposition. A previous report of an insertion/deletion (I/D) polymorphism in intron 16 within the ACE gene implicated an increased risk to develop CRPS I associated with the D allele. However, in the present study the D allele frequency was not increased in CRPS I cases (0.51 for D allele, 0.49 for I allele). Furthermore, there was no co‐segregation of any genotype (DD, ID, II) with the CRPS phenotype in 12 selected familial CRPS I cases from six CRPS I families. In conclusion, the results presented herein render this particular ACE gene polymorphism unlikely to be a predisposing factor for CRPS I.
Differential release of neurotransmitters from superficial and deep layers of the dorsal horn in response to acute noxious stimulation and inflammation of the rat paw
Authors: Dmitrieva Natalia , Rodríguez‐Malaver Antonio J , Pérez Jackeline , Hernández Luis
Published: November 2003

Experimental evidence suggests that release of neurotransmitters in response to acute noxious stimulation and inflammation can differ in superficial and deeper dorsal horn (DH) laminae. Using two different microdialysis probes, we studied changes in levels of glutamate, aspartate, arginine and GABA in dialysates collected from the surface of the spinal cord and within the DH induced by pinching the paw or paw inflammation. In penthotal anaesthetized rats, a flexible microdialysis probe was placed on the dorsal surface of the L4–L5 or L6–S2 spinal segments. In other rats, a rigid microdialysis probe was implanted within the DH of the same segments. Samples were collected every minute before, during and after pinching the hind paw (acute pain), and every half an hour after injecting either carrageenan or saline into the same paw (inflammation‐induced pain). Amino acids were measured by capillary zone electrophoresis with laser‐induced fluorescence detection (CZE‐LIFD). Pinching the paw induced a significant but short lasting increase in extracellular glutamate and aspartate in dialysates from the surface of the DH. Carrageenan, but not saline, injected into the paw significantly increased concentrations of glutamate, aspartate and arginine both on the surface and within the DH of L4–L5 and also within the DH of the L6–S2 segments. The GABA level was significantly increased following carrageenan only within the DH. The maximum increase on the surface was detected 60–120 min after the onset of inflammation whereas the response within the DH reached a maximum between 150 and 180 min after carrageenan. These results indicate that unlike acute mechanical noxious stimulation which enhances amino acid neurotransmitters in surface dialysate, inflammation induced neurotransmitter release in all layers of the DH suggesting sensitization of the DH.
Pharmacological consequences of long‐term morphine treatment in patients with cancer and chronic non‐malignant pain
Authors: Andersen Gertrud , Sjøgren Per , Hansen Steen Honoré , Jensen Niels‐Henrik , Christrup Lona
Published: November 2003

Background. In patients with pain of malignant origin morphine may be administered in high and often increasing doses during extended periods of time. In patients with chronic pain of non‐malignant origin morphine may be an important remedy, and in these cases the goal is to keep the morphine dose stable. The pharmacokinetic as well as the pharmacodynamic consequences of long‐term morphine treatment with special reference to the two most important metabolites of morphine morphine‐6‐glucuronide (M‐6‐G) and morphine‐3‐glucuronide (M‐3‐G) remain to be settled.

Methods. Assessments for pain, sedation and other morphine induced side effects were made several times for 19 cancer patients treated with changing doses of oral sustained release (SR) morphine and twice for 17 non‐cancer patients treated with stable doses of SR morphine. Blood samples were obtained simultaneously and analysed for contents of morphine, M‐3‐G and M‐6‐G by high‐performance liquid chromatography (HPLC).

Results. Significant correlations were found between the daily dose of SR morphine and plasma morphine (r=0.469, p<0.01), plasma M‐6‐G (r=0.677, p<0.01) and plasma M‐3‐G (r=0.827, p<0.01) in the cancer patient group, but only between the daily dose of SR morphine and plasma M‐3‐G (0.662, p<0.01) and plasma M‐6‐G (0.571, p<0.01) in the non‐cancer patient group. Normalised M‐3‐G/M and M‐6‐G/M ratios for the cancer patient group were independent of duration of treatment and daily dose of SR morphine. Likewise in the non‐cancer patient group duration of treatment did not influence the metabolite ratios. Correlations between pain score and plasma morphine, M‐6‐G and M‐6‐G/M were weak in the cancer patient as well as in the non‐cancer patient group making it impossible to draw any conclusion regarding the potential contributory analgesic effect of M‐6‐G. Dryness of the mouth was the most frequent adverse effect reported in the non‐cancer as well as the cancer patient group. In the latter group patients complaining of dryness of the mouth had significantly higher plasma morphine and M‐6‐G concentrations than patients who did not suffer from this side effect. This difference persisted (or was close to significance) when excluding patients receiving antidepressants.

Conclusion. In the cancer patient group neither dose nor treatment period seems to influence morphine glucuronidation. Likewise in the non‐cancer patient group receiving stable doses of morphine duration of treatment does not seem to influence morphine glucuronidation. Dryness of the mouth was positively correlated to high plasma concentrations of morphine and M‐6‐G.
Minimal clinically important changes in chronic musculoskeletal pain intensity measured on a numerical rating scale
Authors: Salaffi Fausto , Stancati Andrea , Silvestri Carlo Alberto , Ciapetti Alessandro , Grassi Walter
Published: November 2003

Objectives. To determine the minimal clinically important difference (MCID) of changes in chronic musculoskeletal pain intensity that is most closely associated with improvement on the commonly used and validated measure of the patient's global impression of change (PGIC), and to estimate the dependency of the MCID on the baseline pain scores.

Methods. This was a prospective cohort study assessing patient's pain intensity by the numerical rating scale (NRS) at baseline and at the 3 month follow‐up, and by a PGIC questionnaire. A one unit difference at the lowest end of the PGIC (“slightly better”) was used to define MCID as it reflects the minimum and lowest degree of improvement that could be detected. In addition we also calculated the NRS changes best associated with “much better” (two units). In order to characterize the association between specific NRS change scores (raw or percent) and clinically important improvement, the sensitivity and specificity were calculated by the receiver operating characteristic (ROC) method. PGIC was used as an external criterion to distinguish between improved or non‐improved patients.

Results. 825 patients with chronic musculoskeletal pain (233 with osteoarthritis of the knee, 86 with osteoarthritis of the hip, 133 with osteoarthritis of the hand, 290 with rheumatoid arthritis and 83 with ankylosing spondylitis) were followed up. A consistent relationship between the change in NRS and the PGIC was observed. On average, a reduction of one point or a reduction of 15.0% in the NRS represented a MCID for the patient. A NRS change score of −2.0 and a percent change score of −33.0% were best associated with the concept of “much better” improvement. For this reason these values can be considered as appropriate cut‐off points for this measure. The clinically significant changes in pain are non‐uniform along the entire NRS. Patients with a high baseline level of pain on the NRS (score of >7 cm), who experienced either a slight improvement or a higher level of response, had absolute raw and percent changes greater that did patients in the lower cohort (score of less than 4 cm).

Conclusions. These results are consistent with the recently published findings generated by different methods and support the use of a “much better” improvement on the pain relief as a clinically important outcome. A further confirmation in other patient populations and different chronic pain syndromes will be needed.
Creep dominates tensile fatigue damage of the cement–bone interface
Authors: Kim Do‐Gyoon , Miller Mark A. , Mann Kenneth A.
Published: November 2003

Fatigue damage from activities of daily living has been considered to be a major cause of aseptic loosening in cemented total hip arthroplasty. The cement–bone interface is one region where loosening could occur, but to date the fatigue response of the interface has not been examined. Cement–bone specimens were prepared from fresh frozen human cadaver tissue using simulated in vivo conditions. Tensile fatigue tests to failure were performed in an environmental chamber. Loss of specimen stiffness (stiffness damage) and permanent displacement after unloading (creep damage) were found in all specimens. At failure, creep damage accounted for the majority (79.9 ± 10.6%) of the total strain damage accumulation at failure (apparent strain, ε = 0.0114 ± 0.00488). A power law relationship between strain‐damage rate and time‐to‐failure showed that the strain‐damage rate was an excellent predictor of the fatigue life of the cement–bone interface. The S–N response of the interface was obtained as a function of the applied stress ratio and the initial apparent strain. The total motion between cement and bone (72.2 ± 29.8 μm) prior to incipient failure due to both stiffness and creep fatigue damage may be sufficient to result in fibrous tissue formation and contribute to eventual clinical loosening. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Long‐term effects of local growth factor (IGF‐I and TGF‐β1) treatment on fracture healing. A safety study for using growth factors
Authors: Schmidmaier Gerhard , Wildemann Britt , Ostapowicz Daniel , Kandziora Frank , Stange Richard , Haas Norbert P. , Raschke Michael
Published: November 2003

Previous studies showed that growth factors dramatically stimulate healing processes in bone. However, the long‐term effect of locally applied growth factors on fracture healing remains unclear. In considering the safety of using growth factors, it is necessary to elucidate that after initial stimulation, the effect stops and the result is a normally healed tissue. Therefore, the purpose of the present study was to investigate the long‐term time course of healing processes during growth factor (GF) stimulated and unstimulated fracture healing in a closed tibial fracture model in rats. A well established local drug delivery system was used. IGF‐I (50 μg) and TGF‐β1 (10 μg) were locally applied using a 10 μm thin polylactide (PDLLA) coating on intramedullary implants. The biomechanical and histomorphometrical results demonstrated a significant stimulation of the fracture healing due to the locally applied growth factors compared to control at days 28 and 42 in agreement with the literature. At the last time point, 84 days after fracture, no differences were measurable in the biomechanical testing and the callus composition between the groups. The callus was consistently in the late phase of remodeling with no remaining cartilage. In conclusion, local growth factor application enhances the healing in the early phase without alteration of the normal healing process. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Sources and paleoclimatic significance of Holocene Bignell Loess, central Great Plains, USA
Authors: Mason Joseph A. , Jacobs Peter M. , Hanson Paul R. , Miao Xiaodong , Goble Ronald J.
Published: November 2003

This paper reexamines the stratigraphy, sources, and paleoclimatic significance of Holocene Bignell Loess in the central Great Plains. A broadly similar sequence of loess depositional units and paleosols was observed in thick Bignell Loess sections up to 300 km apart, suggesting that these sections record major regional changes in the balance between dust deposition and pedogenesis. New optical ages, together with previously reported radiocarbon ages, indicate Bignell Loess deposition began 9000–11,000 yr ago and continued into the late Holocene; some Bignell Loess is <1000 yr old. There is little evidence that Holocene Loess was derived from flood plain sources, as previously proposed. Instead, thick Bignell Loess occurs mainly near the downwind margins of inactive dune fields, particularly atop escarpments facing the dunes. Thus, the immediate loess source was dust produced when the dunes were active. Previous work indicates that widespread episodes of dune activity are likely to have resulted from drier-than-present climatic conditions. The regionally coherent stratigraphy of Bignell Loess can be interpreted as a near-continuous record of climatically driven variation in dune field activity throughout the Holocene.
The last 7500 cal yr B.P. of westerly rainfall in Central Chile inferred from a high-resolution pollen record from Laguna Aculeo (34°S)
Authors: Villa-Martínez Rodrigo , Villagrán Carolina , Jenny Bettina
Published: November 2003

We report multiproxy analyses of a sediment core obtained from Laguna Aculeo that spans the past 7500 years. Laguna Aculeo (33°50′S, 70°55′W) is one of the few natural inland lakes located in the Mediterranean zone of Central Chile, near the northern margin of the influence of the southern westerlies. The record shows elevated pollen counts of halophytes and seasonally drying of the lake basin prior to 5700 cal yr B.P., indicating severe aridity and warmer-than-present conditions. This was followed by the establishment of a fresh-water lake, along with an increase in arboreal and herbaceous plant diversity between 5700 and 3200 cal yr B.P. An intensification of this trend started at 3200 cal yr B.P., along with the abrupt decrease of halophytes until 100 cal yr B.P. Within this humid period, pollen accumulation rates show large-amplitude fluctuations, coeval with numerous turbidite layers, suggesting a highly variable and torrential rainfall pattern. This intense and variable precipitation regime is probably associated with the El Niño–Southern Oscillation (ENSO) phenomenon. We suggest that the modern Mediterranean climate of Central Chile was established at ∼3200 cal yr B.P. Paleovegetation and paleolimnological changes starting at 100 cal yr B.P. correlate with documented human activity surrounding the lake.
Postglacial fire, vegetation, and climate history in the Clearwater Range, Northern Idaho, USA
Authors: Brunelle Andrea , Whitlock Cathy
Published: November 2003

The environmental history of the Northern Rocky Mountains was reconstructed using lake sediments from Burnt Knob Lake, Idaho, and comparing the results with those from other previously published sites in the region to understand how vegetation and fire regimes responded to large-scale climate changes during the Holocene. Vegetation reconstructions indicate parkland or alpine meadow at the end of the glacial period indicating cold-dry conditions. From 14,000 to 12,000 cal yr B.P., abundantPinuspollen suggests warmer, moister conditions than the previous period. Most sites record the development of a forest withPseudotsugaca. 9500 cal yr B.P. indicating warm dry climate coincident with the summer insolation maximum. As the amplification of the seasonal cycle of insolation waned during the middle Holocene,Pseudotsugawas replaced byPinusandAbiessuggesting cool, moist conditions. The fire reconstructions show less synchroneity. In general, the sites west of the continental divide display a fire-frequency maximum around 12,000–8000 cal yr B.P., which coincides with the interval of high summer insolation and stronger-than-present subtropical high. The sites on the east side of the continental divide have the highest fire frequency ca. 6000–3500 cal yr B.P. and may be responding to a decrease in summer precipitation as monsoonal circulation weakened in the middle and late Holocene. This study demonstrated that the fire frequency of the last two decades does not exceed the historical range of variability in that periods of even higher-than-present fire frequency occurred in the past.
A 16,000 14C yr B.P. packrat midden series from the USA–Mexico Borderlands
Authors: Holmgren Camille A. , Peñalba M. Cristina , Rylander Kate Aasen , Betancourt Julio L
Published: November 2003

A new packrat midden chronology from Playas Valley, southwestern New Mexico, is the first installment of an ongoing effort to reconstruct paleovegetation and paleoclimate in the U.S.A.–Mexico Borderlands. Playas Valley and neighboring basins supported pluvial lakes during full and/or late glacial times. Plant macrofossil and pollen assemblages from nine middens in the Playas Valley allow comparisons of two time intervals: 16,000–10,000 and 4000–0 14C yr B.P. Vegetation along pluvial lake margins consisted of open pinyon–juniper communities dominated by Pinus edulis, Juniperus scopulorum, Juniperus cf. coahuilensis, and a rich understory of C4 annuals and grasses. This summer-flowering understory is also characteristic of modern desert grassland in the Borderlands and indicates at least moderate summer precipitation. P. edulis and J. scopulorum disappeared or were rare in the midden record by 10,670 14C yr B.P. The late Holocene is marked by the arrival of Chihuahuan desert scrub elements and few departures as the vegetation gradually became modern in character. Larrea tridentata appears as late as 2190 14C yr B.P. based on macrofossils, but may have been present as early as 4095 14C yr B.P. based on pollen. Fouquieria splendens, one of the dominant desert species present at the site today, makes its first appearance only in the last millennium. The midden pollen assemblages are difficult to interpret; they lack modern analogs in surface pollen assemblages from stock tanks at different elevations in the Borderlands.
1‐Cys peroxiredoxin knock‐out mice express mRNA but not protein for a highly related intronless gene
Authors: Mo Yiqun , Feinstein Sheldon I. , Manevich Yefim , Zhang Qunwei , Lu Lu , Ho Ye-Shih , Fisher Aron B.
Published: November 2003

1‐Cys peroxiredoxin (1‐cysPrx), a member of the peroxiredoxin family with a single conserved cysteine, is a unique antioxidant enzyme. We have generated mice in which the 1‐cysPrx gene has been inactivated; they are viable and fertile. Mice have a highly related intronless gene (1‐cysPrx‐P1, GenBank accession number AF085220) with the same length of open reading frame (224 aa) as 1‐cysPrx but located on a different chromosome. Since the product of this gene possibly could mimic 1‐cysPrx function, we compared expression of 1‐cysPrx and 1‐cysPrx‐P1 in mouse tissues by real‐time polymerase chain reaction and Western blot. 1‐cysPrx mRNA and protein were expressed in all mouse tissues that were examined with the highest expression level in lung. 1‐cysPrx‐P1 mRNA was expressed only in testis. In the 1‐cysPrx ‘knock‐out’ mouse, 1‐cysPrx‐P1 mRNA expression level was similar to the wild type but protein expression was not detected. Thus, mouse 1‐cysPrx‐P1 is an mRNA‐expressed pseudogene that does not result in detectable protein in vivo.
Production of unnatural glucosides of curcumin with drastically enhanced water solubility by cell suspension cultures of Catharanthus roseus
Authors: Kaminaga Yasuhisa , Nagatsu Akito , Akiyama Takumi , Sugimoto Naoki , Yamazaki Takeshi , Maitani Tamio , Mizukami Hajime
Published: November 2003

Catharanthus roseus cell suspension cultures converted exogenously supplied curcumin to a series of glucosides, none of which has been found in nature so far. The efficiency of glucosylation was dependent on culture stage of the cells and medium sucrose concentration. Methyl jasmonate and salicylic acid enhanced the glucoside formation only when they were added to the cultures prior to the addition of curcumin. The glucoside yield was 2.5 μmol/g fresh weight of the cells at an optimal culture condition. The water solubility of curcumin‐4′,4″‐O‐β‐D‐digentiobioside was 0.65 mmol/ml, which was 20 million‐fold higher than that of curcumin.
Selection of novel structural zinc sites from a random peptide library
Authors: Matsubara Teruhiko , Hiura Yuko , Kawahito Osamu , Yasuzawa Mikito , Kawashiro Katsuhiro
Published: November 2003

Zinc ion (Zn2+) can be coordinated with four or three amino acid residues to stabilize a protein's structure or to form a catalytic active center. We used phage display selection of a dodecamer random peptide library with Zn2+ to identify structural zinc sites. The binding specificity for Zn2+ of selected sequences was confirmed using enzyme‐linked immunosorbent and competitive inhibition assays. Circular dichroism spectra indicated that the interaction with Zn2+ induced a change in conformation, which means the peptide acts as a structural zinc site. Furthermore, a search of protein databases revealed that two selected sequences corresponded to parts of natural zinc sites of copper/zinc superoxide dismutase and zinc‐containing ferredoxin. We demonstrated that Zn2+‐binding sequences selected from the random combinatorial library would be candidates for artificial structural zinc sites.
Cyclophilin sensitivity to sanglifehrin A can be correlated to the same specific tryptophan residue as cyclosporin A
Authors: Pemberton Trevor J , Kay John E
Published: November 2003

Sanglifehrin A (SFA) is a recently discovered immunosuppressant drug that shares its intracellular target with the major immunosuppressant drug cyclosporin A (CsA). Both bind to and inhibit the cyclophilins, a diverse family of proteins found throughout nature that share a conserved catalytic domain. Although they share this common protein target, the mechanism of action of the cyclophilin–SFA complex has been reported as distinct from that of the well‐studied cyclophilin–CsA complex. The X‐ray structure of a macrolide analogue of SFA's cyclic region complexed with cyclophilin A has recently been resolved, but this left the placement of the linear region of SFA unresolved. Using five cyclophilins from the fission yeast Schizosaccharomyces pombe, and a mutant of one of these proteins, SpCyp3‐F128W, we have shown that the sensitivity of cyclophilins to SFA can be correlated to the same specific tryptophan residue that has previously been identified to correlate to CsA sensitivity, and that the tail of SFA may be responsible for mediating this sensitivity.
Essential role of the low density lipoprotein receptor‐related protein in vascular smooth muscle cell migration
Authors: Li Yonghe , Lu Wenyan , Bu Guojun
Published: November 2003

The low density lipoprotein receptor‐related protein (LRP) is a multifunctional cell surface receptor highly expressed in human aortic smooth muscle cells. In the present study, we used the short interfering RNA (siRNA) technique to explore the role of LRP in smooth muscle cell migration. We identified an LRP‐specific siRNA that selective silences LRP expression in human aortic smooth muscle cells. As a consequence, LRP‐mediated ligand degradation was significantly reduced. More important, we found that platelet‐derived growth factor‐dependent cell migration was inhibited in cells transfected with LRP siRNA. These results demonstrate an important role of LRP in smooth muscle cell migration.
Molecular classification of cancer types from microarray data using the combination of genetic algorithms and support vector machines
Authors: Peng Sihua , Xu Qianghua , Ling Xuefeng Bruce , Peng Xiaoning , Du Wei , Chen Liangbiao
Published: November 2003

Simultaneous multiclass classification of tumor types is essential for future clinical implementations of microarray‐based cancer diagnosis. In this study, we have combined genetic algorithms (GAs) and all paired support vector machines (SVMs) for multiclass cancer identification. The predictive features have been selected through iterative SVMs/GAs, and recursive feature elimination post‐processing steps, leading to a very compact cancer‐related predictive gene set. Leave‐one‐out cross‐validations yielded accuracies of 87.93% for the eight‐class and 85.19% for the fourteen‐class cancer classifications, outperforming the results derived from previously published methods.
Polyhalogenated benzo‐ and naphthoquinones are potent inhibitors of plant and bacterial ureases
Authors: Ashiralieva Ainura , Kleiner Diethelm
Published: November 2003

Polyhalogenated benzo‐ and naphthoquinones were found to be potent inhibitors of pure ureases from Bacillus pasteurii and Canavalia ensiformis. They also inhibited ureases in whole cells of Helicobacter pylori, Klebsiella oxytoca and Proteus mirabilis. Inhibition was non‐competitive with K
i values in the micromolar range or below. Inhibition was irreversible as shown by equilibrium dialysis. Inhibitory power decreased considerably when halogens were replaced by –OH, –CN, alkoxy or alkyl groups.
Statins induce suppressor of cytokine signaling‐3 in macrophages
Authors: Huang Kuo-Chin , Chen Ching-Wen , Chen Jui-Ching , Lin Wan-Wan
Published: November 2003

Our previous study has shown that lipophilic 3‐hydroxy‐3‐methyl‐glutaryl coenzyme A reductase inhibitors of statins can inhibit interferon‐γ‐induced inducible nitric oxide synthase gene expression in RAW264.7 macrophages. In this study, we showed that lovastatin and fluvastatin are able to upregulate the mRNA expression of the suppressor of cytokine signaling‐3 (SOCS‐3) gene. This effect is specific for SOCS‐3 and could be blocked by mevalonate, farnesyl pyrophosphate and geranylgeranyl pyrophosphate, while it was not affected by inhibitors of protein kinase C and A, mitogen‐activated protein/extracellular signal‐regulated kinase kinase, p38 mitogen‐activated protein kinase, c‐Jun N‐terminal kinase, Src, Raf and Rho kinase. SOCS‐3 expression results in the inhibition of interferon‐γ‐, interleukin‐6‐ and macrophage colony‐stimulating factor‐elicited signal transducer and activator of transcription phosphorylation, suggesting a novel anti‐inflammatory mechanism of statins to down‐modulate the functions of interferon‐γ‐activated macrophages.
Efficacy and tolerability of the long‐term administration of carvedilol in patients with chronic heart failure with and without concomitant diabetes mellitus
Authors: Nodari Savina , Metra Marco , Dei Cas Alessandra , Dei Cas Livio
Published: November 2003

Background:

Diabetes is frequently associated with heart failure and is an independent risk factor for an increased mortality and morbidity. Beta‐blockers are traditionally regarded as relatively contraindicated in patients with diabetes mellitus.

Aim of the study:

To assess the efficacy and tolerability of carvedilol administration in patients with heart failure and concomitant diabetes.

Methods and results:

One hundred ninety‐three patients (68 diabetics, 125 non‐diabetics) with chronic heart failure were assessed by radionuclide ventriculography, cardiopulmonary exercise testing and right heart catheterization before and after 12 months of maintenance carvedilol treatment (mean dose, 40±19 mg daily). Diabetic patients were older and with a lower peak VO2, compared with non‐diabetics. Long‐term carvedilol administration was associated with an improvement in left ventricular function, clinical symptoms, resting and exercise hemodynamic parameters compared to baseline, with no significant difference between the diabetic and the non‐diabetic patients. The incidence of adverse effects was also similar between the two groups. Diabetics had higher all‐cause mortality with a similar mortality and hospitalization rate, compared to non‐diabetics during 33±20 months of follow‐up.

Conclusion:

Concomitant diabetes does not influence the efficacy and tolerability of carvedilol administration in patients with chronic heart failure.
Attitudes toward HIV-positives in dependence on their sexual orientation * Footnote. The author wishes to thank Margit E. Oswald and two anonymous reviewers for their helpful comments on an earlier draft of this paper.
Authors: Hergovich Andreas , Ratky Elisabeth , Stollreiter Marc
Published: November 2003

Homosexual HIV-positives suffer under a double stigma. Moreover, many heterosexuals still associate HIV/AIDS with homosexuality ( Herek & Capitanio, 1999 ). This study examined the connection between belief in a just world, sexual morality and values on the one hand and attitudes towards HIV-positives on the other. Hundred and ninety-nine subjects evaluated an HIV-positive target (homosexual for half of the subjects, heterosexual for the other half) by means of a semantic differential. Results: in general, homosexual HIV-positives were evaluated more negatively than heterosexual HIV-positives. A moderated regression analysis showed a significant effect of values on the rating of the target.
The self and schizophrenia: a cognitive approach
Authors: Nieznanski Marek
Published: November 2003

The aim of the study was to explore the basic features of self-schema in persons with schizophrenia. Thirty two schizophrenic patients and 32 normal controls were asked to select personality trait words from a check-list that described themselves, themselves as they were five years ago, and what most people are like. Compared with the control group, participants from the experimental group chose significantly more adjectives that were common to descriptions of self and others, and significantly less that were common to self and past-self descriptions. These results suggest that schizophrenic patients experience their personality as changing over time much more than do healthy subjects. Moreover, their self-representation seems to be less differentiated from others-representation and less clearly defined than in normal subjects.
The heritability of mental traits in humans: A proposal for a more coherent discussion
Authors: Velden Manfred
Published: November 2003

It is proposed to simplify the debate about the heritability of mental traits in humans by concentrating on two crucial issues: Population specificity of heritability estimates and the relation of these estimates to the malleability of the trait to which they refer. It is demonstrated that due to vast differences between the environmental variations of populations there would have to be a heritability estimate for every imaginable population, and that a heritability estimate allows no predictions whatsoever about the malleability of the trait in question. It is therefore concluded that this field of research should be abandoned.
Electrical conduction mechanism and phase transition studies using dielectric properties and Raman spectroscopy in ferroelectric Pb0.76Ca0.24TiO3 thin films
Authors: Pontes F. M. , Pontes D. S. L. , Leite E. R. , Longo E. , Chiquito A. J. , Pizani P. S. , Varela J. A.
Published: November 2003

We have studied the phase transition behavior of Pb0.76Ca0.24TiO3 thin films using Raman scattering and dielectric measurement techniques. We also have studied the leakage current conduction mechanism as a function of temperature for these thin films on platinized silicon substrates. A Pb0.76Ca0.24TiO3 thin film was prepared using a soft chemical process, called the polymeric precursor method. The results showed that the dependence of the dielectric constant upon the frequency does not reveal any relaxor behavior. However, a diffuse character-type phase transition was observed upon transformation from a cubic paraelectric phase to a tetragonal ferroelectric phase. The temperature dependency of Raman scattering spectra was investigated through the ferroelectric phase transition. The soft mode showed a marked dependence on temperature and its disappearance at about 598 K. On the other hand, Raman modes persist above the tetragonal to cubic phase transition temperature, although all optical modes should be Raman inactive above the phase transition temperature. The origin of these modes must be interpreted in terms of a local breakdown of cubic symmetry by some kind of disorder. The lack of a well-defined transition temperature suggested a diffuse-type phase transition. This result corroborate the dielectric constant versus temperature data, which showed a broad ferroelectric phase transition in the thin film. The leakage current density of the PCT24 thin film was studied at elevated temperatures, and the data were well fitted by the Schottky emission model. The Schottky barrier height of the PCT24 thin film was estimated to be 1.49 eV.
Computing granular avalanches and landslides
Authors: Pitman E. Bruce , Nichita C. Camil , Patra Abani , Bauer Andy , Sheridan Michael , Bursik Marcus
Published: November 2003

Geophysical mass flows—debris flows, volcanic avalanches, landslides—are often initiated by volcanic activity. These flows can contain O(106–107) m3 or more of material, typically soil and rock fragments that might range from centimeters to meters in size, are typically O(10 m) deep, and can run out over distances of tens of kilometers. This vast range of scales, the rheology of the geological material under consideration, and the presence of interstitial fluid in the moving mass, all make for a complicated modeling and computing problem. Although we lack a full understanding of how mass flows are initiated, there is a growing body of computational and modeling research whose goal is to understand the flow processes, once the motion of a geologic mass of material is initiated. This paper describes one effort to develop a tool set for simulations of geophysical mass flows. We present a computing environment that incorporates topographical data in order to generate a numerical grid on which a parallel, adaptive mesh Godunov solver can simulate model systems of equations that contain no interstitial fluid. The computational solver is flexible, and can be changed to allow for more complex material models, as warranted.
Stability of a sheared particle suspension
Authors: Kumaran V.
Published: November 2003

A stability analysis is carried out for a gas–particle suspension in which the energy dissipation occurs due to the viscous drag force exerted on the particles. The flow is driven by two types of energy sources, an imposed mean shear and fluid velocity fluctuations, in the limit where the time between collisions τc is small compared to the viscous relaxation time τv, so that the dissipation of energy between collisions is small compared to the energy of a particle. Constitutive relations from the kinetic theory of dense gases are used when the flow is driven by the mean shear. The effect of fluid velocity fluctuations is incorporated using an additional diffusive term in the Boltzmann equation for the particle velocity distribution, and this leads to an additional “diffusion” stress. For a suspension driven by fluid velocity fluctuations, it is found that perturbations are always stable. For a suspension driven by mean shear, the viscous relaxation time is large compared to the collision time for Ḡτv≫1, where Ḡ is the mean strain rate. The rate of diffusion of energy is small compared to the rate of dissipation for k*≪(Ḡτv)−1, where k* is the wave number scaled by the mean free path. In this regime, it is found that density perturbations are unstable in all three directions in the limit of low volume fraction, but become stable when the volume fraction is increased beyond a critical value. For k*≫(Ḡτv)−1, the rate of diffusion of energy is large compared to the rate of dissipation, and it is found that perturbations are always stable. The transition between these two regimes is obtained numerically in the dilute limit, and the neutral stability curves for the density perturbations are obtained. It is found that in the gradient-vorticity plane, the transition wave number is proportional to (Ḡτv)−1 in the limit (Ḡτv)≫1.
Suppressed pinning field of a trapped domain wall due to direct current injection
Authors: Kimura T. , Otani Y. , Yagi I. , Tsukagoshi K. , Aoyagi Y.
Published: November 2003

We investigate the influence of the dc current injection on trapped domain walls in magnetic nanostructures designed for high precision anisotropy magnetoresistance measurements. The results obtained for a simple strip with no trapped domain wall are compared with those for the strip with the trapped domain wall. The depinning field of the domain wall decreases significantly when the electron current is applied along the direction of the domain wall propagation. On the other hand, the switching field only shows a small reduction when the electron current is opposed to the domain wall propagation. The origin of this behavior can be explained by considering Joule heat as well as an additional pressure exerted on the domain wall due to the transfer of the spin angular momentum from the spin-polarized current to the local magnetic moment.
Effect of collisions on the dispersed phase fluctuation in a dilute tube flow: Experimental and theoretical analysis
Authors: Caraman N. , Borée J. , Simonin O.
Published: November 2003

Measurements of particle fluctuation in a fully developed pipe flow at moderate Reynolds number is performed in this study. The present data are obtained by using a two-component phase Doppler anemometer. The radial profiles are measured at a distance of 0.2 diameter downstream the exit of the tube. At this location, the core flow still carries all the properties of the tube turbulence. A low mass loading of partly responsive particles is considered. The Stokes number of these partly responsive particles is of order 3 when the integral turbulent time scale on the axis of the tube flow is used. The velocity statistics are analyzed up to the third-order moments and we show that the radial turbulent transport of fluctuating kinetic energy is much higher for the particles than for the fluid. Radial balances of longitudinal and radial kinetic stresses of the particles are examined. Particle–particle collisions have a negligible direct effect on the evolution of the longitudinal fluctuating velocity. However, even at this low mass loading, we prove that particle–particle collisions and redistribution from the very large streamwise velocity variance to the radial velocity variance in the near wall region strongly influence the radial fluctuation of the particles. In the core region, a quadrant analysis enables the detection of low streamwise velocities focusing toward the axis and the corresponding quadrants are strongly dominant for the glass beads. We expect that the partly responsive particles, because of their inertia, keep some memory of the lower streamwise velocity existing in the near wall region while they fly across the tube. The collisions in the near wall region are, therefore, expected to have a strong indirect influence on the whole kinetic-energy balance in the tube by partly driving the radial transport of the fluctuating kinetic energy of the particles. This effect should be particularly strong in this circular geometry because events from any azimuthal directions converge in the central region.
Electrical properties and electric field-induced antiferroelectric–ferroelectric phase transition in Nd3+-doped lead strontium zirconate titanate ceramics
Authors: Yu Yongjian , Singh Raj N.
Published: November 2003

Undoped and 1–3 at. % Nd3+-doped lead strontium zirconate titanate ceramics, which were located near the tetragonal antiferroelectric (AFE) and rhombohedral ferroelectric (FE) phase boundary, were prepared by tape casting and sintering. The influence of the electric field-induced AFE to FE phase transition on the piezoelectric and strain behavior was studied. Attempts were made to increase the field-induced strain by Nd3+ doping and its effect on the dielectric properties. Room temperature resistivity was also measured and explained by the defects produced. An in situ x-ray diffraction technique was developed for direct observation of the unit cell dimensions associated with the field-induced AFE to FE phase transition. The results indicated that a change in unit cell volume was responsible for the large field-induced strain associated with the AFE–FE phase transition.
Global destabilization of flow over a backward-facing step
Authors: Kaiktsis Lambros , Monkewitz Peter A.
Published: November 2003

Global destabilization of two-dimensional flow over a backward-facing step embedded in a channel, i.e., flow in a plane channel with a sudden expansion, is investigated by numerical simulations using a spectral element method. In the low Reynolds number regime where the two-dimensional flow is steady without manipulation, self-excited oscillations of the entire flow are induced by appropriate simultaneous suction at the step face and blowing at the wall adjacent to the step. The boundary between steady and time-dependent (destabilized) flow is determined as a function of the streamwise extent of the blowing region and its position relative to the step, for an expansion ratio of approximately two, a Reynolds number fixed at Re=1000, and equal suction and blowing mass flow rates. The computed periodic, globally synchronized flow regimes are characterized using instantaneous streamline patterns, time traces of physical quantities, and proper orthogonal decomposition of the velocity fields. The global flow behavior is also related to the absolute instability properties of the local streamwise velocity profiles. Preliminary three-dimensional simulations finally suggest that the 2-D unsteady flows obtained in the present study are, in general, susceptible to three-dimensional secondary instabilities. Nevertheless, the first experiments suggest that the 2-D analysis provides a qualitatively correct description of the flow transitions and that practical applications of this wall-blowing and -suction scheme, such as mixing enhancement, may be feasible.
Oscillations of low-density barium photoplasma in electric field
Authors: Majumder A. , Mago V. K. , Kathar P. T. , Das A. K.
Published: November 2003

A low-density barium photoplasma has been generated by two-step photoionization in an atomic beam. The transition from independent particle nature to collective effects has been observed in a V-shaped potential well. The potential is produced by a plate–grid–plate geometry in which the grid is negatively biased while the plates are grounded. Analytical expressions for the ion currents on the plates and grid have been deduced for a charge particle moving in the potential well and compared with experiments. The results are in good agreement and gave a method to estimate the ion transmission factor for the grid.
Oscillatory instability in multilayer systems
Authors: Simanovskii I. , Georis P. , Nepomnyashchy A. , Legros J.-C.
Published: November 2003

The paper presents the space experimental results on Marangoni–Benard instability in a real symmetric three-layer system with close values of thermal diffusivities of fluids. For the first time a pure thermocapillary phenomenon has been experimentally observed under microgravity conditions where buoyancy forces can be neglected. The experimental results confirm the existence of theoretically predicted oscillatory instability, essentially connected with the interaction of the interfaces. Nonlinear regimes of the oscillatory convection are investigated by means of the finite-difference method.
Vortex-accelerated secondary baroclinic vorticity deposition and late-intermediate time dynamics of a two-dimensional Richtmyer–Meshkov interface
Authors: Peng Gaozhu , Zabusky Norman J. , Zhang Shuang
Published: November 2003

We study the vortex-accelerated secondary baroclinic vorticity deposition (VAVD) at late-intermediate times, and dynamics of sinusoidal single-mode Richtmyer–Meshkov interfaces in two dimensions. Euler simulations using a piecewise parabolic method are conducted for three post-shock Atwood numbers (A*), 0.2, 0.635, and 0.9, with Mach number (M) of 1.3. We initialize the sinusoidal interface with a slightly “diffuse” or small-but-finite thickness interfacial transition layer to facilitate comparison with experiment and avoid ill-posed phenomena associated with evolutions of an inviscid vortex sheet. The thickness of the interface is chosen so that there are no secondary structures along the interface prior to the multivalue time tM, which is defined as the time when the extracted medial axis of an interfacial layer first becomes multivalued. For an interval of 11tM beyond tM, the simulations reveal nearly monotonic strong growth of both positive and negative baroclinic circulation in a vortex bilayer pattern inside the complex roll-up region. The circulations grow and secondary baroclinic circulation dominates at intermediate times, especially for higher A*. This vorticity deposition is due to misalignment of density gradient across the interface and vortex-centripetal acceleration (secondary baroclinic), and enhanced by the intensification of interfacial density gradient arising from the vortex-induced strain. Our simulation results for A*=0.635 agree with the recent air–sulfur hexafluoride (SF6) experiment of Jacobs and Krivets [Proceedings of the 23rd International Symposium on Shock Waves, Fort Worth, Texas, (2001)], including several large-scale features of the evolving mushroom structure: The usual interface spike-bubble amplitude growth rate ȧ and the dimensions of the spike roll-up cavity. VAVD plays an important role in the intermediate time dynamics of the interfaces. Our amplitude growth rate ȧ disagrees with the O(t−1) result of Sadot et al. [Phys. Rev. Lett. 80, 1654 (1998)]. Instead, it approaches a constant which increases with A*(⩽0.9). An adjusting periodic single point vortex model which uses the calculated net circulation magnitude and its location, gives excellent results for the amplitude growth rates to late-intermediate times at low Atwood numbers (A*=0.2,0.635). The evolution of enstrophy, vorticity skewness, and flatness are quantified for the entire run duration, and one-dimensional averaged kinetic-energy spectra are presented at several times.