bluuebunny/crossref_metadata_2025 huggingface dataset:
Consumer Response to Decision Conflict From Negatively Correlated Attributes: Down the Primrose Path or Up Against the Wall?
Authors: Hansen David E. , Helgeson James G.
Published: February 2004

In a controlled experiment, information format and prior knowledge of risk‐related decision attributes altered the response to decision conflict produced by negatively correlated attributes (NCA) in choice under uncertainty. When dominated choice alternatives were presented in a format in which the displayed attributes were not negatively correlated, decision makers used a simple choice process based on the displayed information. This allowed them to detect the dominated alternatives, regardless of their prior knowledge. However, when the same alternatives were presented in a format in which the displayed attributes were negatively correlated, the more‐knowledgeable decision makers used a compensatory choice process based on the displayed attributes and, consequently, missed the dominated alternatives. The less‐knowledgeable participants, who were unable to use the displayed attributes because of their lack of expertise, calculated the nondisplayed attributes and detected the dominated alternatives. With NCA, the more‐knowledgeable participants followed a conflict‐resolution strategy using the displayed NCAs, whereas the less‐knowledgeable individuals followed a conflict‐avoidance strategy using the uncorrelated, nondisplayed attributes that inadvertently revealed the dominance structure of the decision. The implications of person factors for the effects of NCA and in other types of decisions with NCA are discussed.
The Long‐Term Predictive Validity of the Consumers’ Need for Uniqueness Scale
Authors: Tian Kelly Tepper , McKenzie Karyn
Published: February 2004

This research examines the long‐term ability of the consumers’ need for uniqueness measure to predict consumers’ valued possessions, shopping behaviors, and experiences. Consumers’ need for uniqueness reflects individual differences in counterconformity motivation (i.e., the pursuit of differentness relative to others) that is manifest in consumer responses. This research reports on 2 longitudinal assessments of the scale's predictive validity using data collected at 4 stages from a consumer mail‐survey sample. One year following initial responses to the trait measure, respondents participated in a second survey in which they photographed and rank ordered their valued possessions. In a third survey, the photographs served as cues to obtain responses to ratings of possession benefits and to questions regarding acquisition of the possession. Overall, the results support a number of hypotheses regarding the relation of consumers’ need for uniqueness to salient possession benefits, types of goods comprising consumers’ valued possessions, and shopping behaviors associated with acquiring valued possessions. Two years following initial responses to the trait measure, members of the consumer mail panel completed a fourth survey, indicating their participation in various uniqueness‐enhancing consumer activities. Results support the stability and predictive validity of the measure over the 2‐year period. Because the design of possessions and endorsed uniqueness‐enhancing activities considered in the consumer mail panel studies varied across individuals, an additional study was conducted that demonstrated the scale's ability to predict individuals’ counterconformity responses to the same choice situation.
The Bone Morphogenetic Protein System In Mammalian Reproduction
Authors: Shimasaki Shunichi , Moore R. Kelly , Otsuka Fumio , Erickson Gregory F.
Published: February 2004

Using molecular, cellular, and genetic approaches, recent studies examining the role of the bone morphogenetic protein (BMP) family of growth factors in the reproductive system have led to significant breakthroughs in our understanding of mammalian reproduction and fertility. Gene expression studies have revealed that key components of the BMP system (ligands, receptors, signaling molecules, and binding proteins) exhibit coordinated spatial and temporal expression patterns in fundamental cell types throughout the reproductive system. Availability of recombinant BMPs has enabled functional studies that have demonstrated important biological activities of BMPs in controlling cellular proliferation, differentiation, and apoptosis in reproductive tissues. The physiological importance of the BMP system for mammalian reproduction has been further highlighted by the elucidation of the aberrant reproductive phenotypes of animals with naturally occurring mutations or targeted deletions of certain BMP family genes. Collectively, these studies have established the concept that the BMP system plays a crucial role in fertility in female and male mammals. The purpose of this article is to review the evidence underpinning the importance of the BMP system in mammalian reproduction.
High Selective Conversion of Poly(ethylene terephthalate) into Oil Using Ca(OH)2
Authors: Yoshioka Toshiaki , Kitagawa Eisaku , Mizoguchi Tadaaki , Okuwaki Akitsugu
Published: February 2004

It is a well known fact that sublimation substances, such as benzoic acid and terephthalic acid, are produced in the thermal decomposition of PET, and this causes problems in plastic recycling plants. However, it is clear that the addition of Ca(OH)2 affects the high selectivity of benzene without producing sublimation substances. The yield of benzene was 35.85 wt % at 700 °C and a 10.0 Ca(OH)2/PET molar ratio. This value means that the selectivity of benzene is 78.8% for liquid products, and 85.1 wt % for aromatic ring in input PET.
Electrochemical Behavior of Methyl- and Butyl- Terminated Si(111) in Aqueous Solution
Authors: Niwa Daisuke , Inoue Tomoyuki , Fukunaga Hiroshi , Akasaka Toru , Yamada Taro , Homma Takayuki , Osaka Tetsuya
Published: February 2004

Formation of the methyl- and n-butyl monolayer on (Cl)–Si(111) surfaces by using the Grignard reaction and their electrochemical behavior was investigated. The modified Si(111) surfaces were indicated to be closely packed with a single moiety species. The methyl-modified Si(111) surface was composed of (1 × 1) adlattice structure. The methyl-modified surface was stable in aqueous solution, and showed essentially good electrical conductive property with p-n junction like behavior.
Novel Ultrasonication-assisted Carbonyl Allylation Mediated by SnCl2 in Water
Authors: Wang Jun , Yuan Gu , Dong Chang-Qing
Published: February 2004

Under ultrasonication, it was found that SnCl2 could efficiently mediate the aqueous Barbier reactions between carbonyl compounds and allyl bromide to give the corresponding homoallylic alcohols in high yields without using any Lewis acid catalyst.
Potassium Hydrogen Sulfate-Catalyzed Reactions of Indoles: A Mild, Expedient Synthesis of Bis-indolylmethanes
Authors: Nagarajan Rajagopal , Perumal Paramasivan T
Published: February 2004

Biologically important bis-indolylmethanes and their derivatives were prepared in good yields by the electrophilic substitution of indole with aldehydes catalyzed by potassium hydrogen sulfate.
Water Sorption of CaCl2-Containing Materials as Heat Storage Media
Authors: Liu Chun Yi , Morofuji Kentaro , Tamura Kenji , Aika Ken-ichi
Published: February 2004

The water sorption behavior of CaCl2-containing materials as heat transfer media was studied. Amount of the water sorption on CaCl2-containing materials was higher than those on the zeolites at the higher humidity region. Heat storage capacity of 33 wt % CaCl2/FSM16 (1200 MJ m−3) was 3.5 times as high as Na form Y-zeolite at 18.7 Torr of water vapor.
Palladium-Catalyzed H–D Exchange Reaction under Hydrothermal Condition
Authors: Matsubara Seijiro , Yokota Yutaka , Oshima Koichiro
Published: February 2004

Alkenes and alkanes were converted into fully deuterium labelled ones by treatment with palladium on charcoal and deuterium oxide under hydrothermal condition. The simple method to get fully deuterium labelled compounds is easy to apply to various types of organic compounds.
Partly Nonparametric Approach for Determining the Limit of Detection
Authors: Linnet Kristian , Kondratovich Marina
Published: February 2004

Background: According to recent International Organization for Standardization (ISO) standards, the limit of detection (LoD) of an assay should be estimated taking both type I (α) and II (β) errors into account. The suggested procedure, however, supposes gaussian distributions of both blank and sample measurements and a linear calibration curve. In clinical chemistry, asymmetric, nongaussian blank distributions are common, and the calibration curve may be nonlinear. We present a partly nonparametric procedure that takes these aspects into account.

Methods: Using theoretical distribution models and simulation studies, we developed a LoD estimation procedure suitable for the field of clinical chemistry that is partly based on nonparametric statistics.

Results: For sample size n, the nonparametrically determined 95th percentile of the blank measurements {obtained as the value of the [n(95/100) + 0.5]th ordered observation} defines the limit for results significantly exceeding zero [limit of blank (LoB)]. The LoD is the lowest value that is likely to yield a result exceeding the LoB. LoD is estimated as: LoB + cβ × SDS, where SDS is the analytical SD of a sample with a low concentration; cβ = z1 − β/[1 − 1/(4 × f)]; z1 − β is the standard normal deviate; and f is the number of degrees of freedom for estimation of SDS. cβ is approximately equal to 1.65 for a type II error of 5%. Approaches and needed tabular values for calculation of confidence limits are presented as well as sample size. Worked examples are given to illustrate estimation and verification of the limit of detection. Simulation results are used to document performance.

Conclusion: The proposed procedure appears useful for application in the field of clinical chemistry and promotes a standardized approach for estimating LoDs of clinical chemistry assays.
Inflammation and arterial stiffness in systemic vasculitis: A model of vascular inflammation
Authors: Booth A. D. , Wallace S. , McEniery C. M. , Yasmin  , Brown J. , Jayne D. R. W. , Wilkinson I. B.
Published: February 2004

Objective

Arterial stiffness, an independent determinant of cardiovascular risk, is regulated by both structural and functional factors, including endothelium‐derived nitric oxide. Endothelial dysfunction is associated with acute and chronic systemic inflammation. However, the role of systemic inflammation in arterial stiffening has not been determined. The aim of this study was to investigate the relationship between inflammation and arterial stiffness in patients with antineutrophil cytoplasmic antibody–associated systemic vasculitis (AASV) as a model of systemic inflammation.

Methods

Thirty‐one patients with AASV (15 with active disease) and 32 age‐matched controls were studied. Pulse wave velocity (PWV) and the augmentation index (AIx) were assessed noninvasively and related to serum levels of C‐reactive protein (CRP), interleukin‐6, and tumor necrosis factor α.

Results

In subjects with active disease, the AIx, PWV, and level of CRP were elevated compared with that in controls (mean ± SEM 31 ± 3% versus 22 ± 2% [P = 0.003], 9.2 ± 0.7 versus 7.5 ± 0.3 meters/second [P = 0.03], and 16.0 ± 4.0 versus 1.1 ± 0.1 mg/liter [P < 0.001], respectively). However, PWV and the AIx were not significantly different between patients with disease in remission and controls (8.0 ± 0.5 versus 7.5 ± 0.3 meters/second and 19 ± 3% versus 22 ± 2%, respectively). The CRP level was positively correlated with both PWV and the AIx. Multiple regression analysis indicated that age, mean arterial pressure (MAP), and CRP were independently related to PWV, and that age, MAP, CRP, sex, and heart rate were associated with the AIx.

Conclusion

These data indicate that AASV is associated with increased arterial stiffness, and that stiffness correlates with the degree of active inflammation.
Inhibition of CD95 apoptotic signaling by interferon‐γ in human osteoarthritic chondrocytes is associated with increased expression of FLICE inhibitory protein
Authors: Grassi Francesco , Piacentini Anna , Cristino Sandra , Toneguzzi Stefania , Facchini Andrea , Lisignoli Gina
Published: February 2004

Objective

Cartilage homeostasis dysregulation during osteoarthritis (OA) has been linked to an increased rate of apoptosis of chondrocytes, the only cell type resident in the cartilage. In addition, the CD95–CD95 ligand (the Fas system) has emerged as one of the major pathways of cell death in the cartilage. We undertook the present study to investigate the role of interferon‐γ (IFNγ) in the regulation of the Fas system by analyzing the modulation of intracellular signaling molecules (FLICE inhibitory protein [FLIP] and caspases 3 and 8) in primary cultures of human OA chondrocytes.

Methods

CD95‐induced apoptotic death of human OA chondrocytes was analyzed in the presence or absence of IFNγ using cell death immunoassay for apoptosis, real‐time polymerase chain reaction for FLIP and caspase 8 expression, Western blotting for FLIP, and proteolytic activity for caspases 3 and 8.

Results

CD95‐induced apoptotic death of human OA chondrocytes was strongly counteracted by IFNγ treatment, although the surface expression of CD95 was slightly up‐regulated by this cytokine. The messenger RNA (mRNA) expression of FLIP and caspase 8, mediators involved in CD95 signaling, revealed that FLIP expression in human OA chondrocytes was significantly up‐regulated (2‐fold increase) by IFNγ treatment. Moreover, the FLIP:caspase 8 mRNA ratio increased significantly. FLIP up‐regulation by IFNγ was confirmed at the protein level. Caspase 8 and caspase 3 proteolytic activities, both induced in these cells by stimulation with anti‐CD95, were also significantly down‐modulated by IFNγ.

Conclusion

These findings suggest that IFNγ impairs CD95‐mediated signaling and apoptotic death in human chondrocytes. Its mechanism of action involves down‐regulation of caspase 8 and caspase 3 activities and increased expression of the antiapoptotic protein FLIP, suggesting an interesting mechanism for the inhibition of chondrocyte apoptosis.
How safe is primary knee replacement surgery? Perioperative complication rates in Northern Illinois, 1993–1999
Authors: Feinglass Joe , Amir Hagay , Taylor Patricia , Lurie Ithai , Manheim Larry M. , Chang Rowland W.
Published: February 2004

Objective

To describe inpatient complications for primary total knee replacement (TKR) in a period of rapidly growing orthopedic surgery capacity, declining length of stay, and more frequent discharge to rehabilitation facilities.

Methods

Complication incidence according to published coding algorithms was estimated for 35,531 primary TKR admissions of northern Illinois residents to 65 Illinois hospitals. Complication odds were estimated as a function of patients' clinical and sociodemographic status, hospital volume, residency training, TKR length of stay, International Classification of Diseases, Ninth Revision (ICD‐9) coding intensity, and discharges to skilled nursing or rehabilitation facilities.

Results

Primary TKR admissions increased 36% between 1993 and 1999, length of stay declined 43%, average ICD‐9 code use increased 31%, and rehabilitation discharges increased 68%. Major complication rates declined 44% (12.4% to 6.9%; P < 0.0001) over this period, reflecting a 50% reduction in the adjusted odds of complication between 1993 and 1999. There was no association of procedure volume and outcome.

Conclusion

It is likely that the reduction in complications reflects true safety improvements as well as reduced length of stay.
Concerns of patients actively contemplating total knee replacement: Differences by race and gender
Authors: Chang Huan J. , Mehta Priya S. , Rosenberg Aaron , Scrimshaw Susan C.
Published: February 2004

Objective

To examine differences by race/ethnicity and gender in patients' concerns regarding total knee replacement (TKR).

Methods

Focus groups of patients actively considering TKR were conducted. Discussion included patients' questions and concerns regarding TKR. The software ATLAS.ti was used to tabulate themes by race/ethnicity and gender. Concerns raised by focus group participants were compared with thematic content from patient joint replacement information materials. This comparison used patient literature from 3 high‐volume academic TKR centers, the Arthritis Foundation, and the American Academy of Orthopedic Surgeons.

Results

All groups shared similar concerns. However, some issues were more prevalent among certain gender and racial groups. For instance, concerns regarding anesthesia were more important to white Americans and concerns regarding recovery were more important to women. Some of these concerns were not addressed in the available patient literature.

Conclusions

Different gender and racial subgroups focus on different concerns when considering TKR. These differences may contribute to gender and race/ethnicity disparity seen in TKR use.
Responsiveness and discriminative capacity of the assessments in ankylosing spondylitis disease‐controlling antirheumatic therapy core set and other outcome measures in a trial of etanercept in ankylosing spondylitis
Authors: Wanders Astrid J. B. , Gorman Jennifer D. , Davis John C. , Landewe Robert B. M. , Van Der Heijde Désirée M. F. M.
Published: February 2004

Objective

To investigate the responsiveness and discriminative capacity, and the relationship between both, of instruments selected for the disease‐controlling antirheumatic therapy (DC‐ART) core set by the Assessments in Ankylosing Spondylitis Working Group (ASAS).

Methods

Responsiveness and discriminative capacity of different measures reflecting disease activity and function, either included in the ASAS DC‐ART core set or not, were evaluated in a randomized controlled clinical trial comparing etanercept with placebo in patients with ankylosing spondylitis. Guyatt's method was used as the primary analysis for responsiveness, and Student's t‐test for discriminative capacity.

Results

At day 28 of therapy, almost all measures indicated moderate to large responsiveness in the etanercept group (Guyatt 0.60–3.11). Some scales of the Short Form 36 (general health, mental component summary, and role emotional), the modified Schober's test, and the Fatigue Severity Scale were not responsive. The results were similar if analyzed at day 112 of therapy. Peripheral joint counts, joint scores, and occiput‐to‐wall distance could not be evaluated due to a floor effect. In general, the relation between responsiveness and discriminative capacity was strong: Measures that demonstrated high responsiveness also showed high between‐group t values.

Conclusion

Measures included in the ASAS DC‐ART core set, except modified Schober's test, have good responsiveness and good discriminatory capacity. Some measures could not be evaluated due to a floor effect.
Measuring systemic lupus erythematosus activity during pregnancy: Validation of the lupus activity index in pregnancy scale
Authors: Ruiz‐Irastorza G. , Khamashta M. A. , Gordon C. , Lockshin M. D. , Johns K. R. , Sammaritano L. , Hughes G. R. V.
Published: February 2004

Objective

To validate the Lupus Activity Index in Pregnancy (LAI‐P) scale as a diagnostic tool for lupus flares during pregnancy and the puerperium.

Methods

The LAI‐P is a modified activity scale specific for pregnancy. Thirty‐eight pregnant women with systemic lupus erythematosus (SLE) were prospectively followed in 3 clinics specific for lupus in pregnancy. On each visit, LAI‐P was calculated. A modified physician global assessment (m‐PGA) scale was used as gold standard (0 = no activity, 1 = mild‐moderate activity, 2 = severe activity). A change ≥ 0.25 in LAI‐P was predefined as a flare according to previous studies in nonpregnant patients. For the purposes of the study, each visit was considered as an independent case.

Results

During the study period, 158 visits took place for a total 621 patient‐weeks. Sensitivity to change was high (standardized response mean for LAI‐P = 1.6). We found a significant association between LAI‐P and m‐PGA (P < 0.002 in all regression models performed). Sensitivity, specificity, and positive and negative predictive values were 0.93, 0.98, 0.88, and 0.99. Positive and negative likelihood ratios were 49 and 0.07, respectively.

Conclusions

LAI‐P has a high sensitivity to changes in lupus activity, a significant correlation with m‐PGA, and high sensitivity, specificity, predictive values, and likelihood ratios for diagnosing SLE flares during pregnancy and the puerperium.
Assessing risk for violence among male and female civil psychiatric patients: the HCR‐20, PCL:SV, and VSC
Authors: Nicholls Tonia L. , Ogloff James R. P. , Douglas Kevin S.
Published: February 2004

This study evaluated the predictive validity of violence risk assessments conducted using the HCR‐20, the Psychopathy Checklist: Screening Version (PCL:SV), and by the Violence Screening Checklist (VSC) in a sample of 268 involuntarily hospitalized male and female psychiatric patients. Information pertaining to violence and crime was coded from medical charts and correctional records. The HCR‐20/PCL:SV evidenced modest non‐significant associations in postdictive assessments of inpatient violence among men. Moderate to strong significant associations were found between the HCR‐20/PCL:SV and inpatient violence among women. Pseudo‐prospective assessments using the HCR‐20 and PCL:SV resulted in moderate to large relationships with violence and crime in men and women following community discharge. It is concluded that the VSC is a promising tool for assessing acute inpatient violence risk with men. Findings offer preliminary validation of the predictive validity of the HCR‐20 and PCL:SV with female civil psychiatric patients. Copyright © 2004 John Wiley & Sons, Ltd.
Baby rape in South Africa
Authors: Richter Linda M.
Published: February 2004

There is historical evidence of the rape of infants and toddlers, and contemporary ‘baby rapes’ have been reported in a number of countries. In South Africa, the rape of infants and toddlers occurs at a low but consistent level. The acute public recognition of the rape of infants and toddlers in South Africa was occasioned by the case of a particularly shocking, widely reported rape in late 2001, followed in rapid succession by the rape of several other infants. Attempts to explain the rape of infants and toddlers include the socialization inﬂuences on men of the country's violent apartheid past, as well as virgin cleansing myths which have arisen in the context of the country's rampant HIV/AIDS epidemic. Added to this is an uneven child rights environment and a poorly functioning police and justice system. Even under the concerted inﬂuence of environmental pressures, the rape of an infant or a toddler is an extremely brutal act which requires both psychological and social explanation. Copyright © 2003 John Wiley & Sons, Ltd.
Modeling of Radial Flow Reactors of Oxidative Reheat Process for Production of Styrene Monomer
Authors: Ahari J.S. , Kakavand M. , Farshi A.
Published: February 2004

Styrene plays an important role in industrial production plants due to its increasing use in the production of various products. Thus, availability of a simulating program for styrene monomer reactors is of major importance in reducing the problems of a styrene unit. In oxidative reheat technology, styrene monomer is produced from ethylbenzene dehydrogenation in radial flow reactors in the presence of the generated heat from hydrogen oxidation reaction. In this article mass, energy and momentum equations on radial direction are developed for styrene monomer reactors. Required kinetic rates and parameters have been adopted from the literature [1,2]. Then, by means of experimental data from industrial reactors and sequential quadratic programming (SQP) methods, suitable kinetic parameters are obtained. Comparison of simulator prediction data with industrial ones show that the simulation has been achieved adequately.
An Integrated Process of H2O2 Production through Isopropanol Oxidation and Cyclohexanone Ammoximation
Authors: Liang X. , Mi Z. , Wang Y. , Wang L. , Zhang X. , Liu T.
Published: February 2004

The possibility of the integration of the processes of H2O2 production through isopropanol partial oxidation and the direct ammoximation of cyclohexanone with H2O2 and NH3 catalyzed by TS‐1 was investigated. The results of isopropanol partial oxidation showed that around 7.5 % yield of H2O2 was obtained at 110 °C, 10 atm, 2 h, and after fractionation, a H2O2 solution with the typical composition 25.2 wt.‐% H2O2, 10.3 wt.‐% isopropanol, 0.29 wt.‐% acetone, 0.45 wt.‐% phosphoric acid and 0.43 wt.‐% acetic acid was obtained. The presence of these impurities up to the above levels did not appreciably influence the ammoximation of cyclohexanone in terms of the conversion of cyclohexanone and the selectivity to cyclohexanone oxime. The results indicate that the processes of H2O2 production through isopropanol partial oxidation and the ammoximation of cyclohexanone can be integrated.
Microglial major histocompatibility complex glycoprotein‐1 in the axotomized facial motor nucleus: Regulation and role of tumor necrosis factor receptors 1 and 2
Authors: Bohatschek M. , Kloss C.U.A. , Hristova M. , Pfeffer K. , Raivich G.
Published: February 2004

Presentation of antigen is key to the development of the immune response, mediated by association of antigen with major histocompatibility complex glycoproteins abbreviated as MHC1 and MHC2. In the current study, we examined the regulation of MHC1 in the brain after facial axotomy. The normal facial motor nucleus showed no immunoreactivity for MHC1 (MHC1‐IR). Transection of the facial nerve led to a strong and selective up‐regulation of MHC1‐IR on the microglia in the affected nucleus, beginning at day 2 and reaching a maximum 14 days after axotomy, coinciding with a peak influx of the T lymphocytes that express CD8, the lymphocyte coreceptor for MHC1. Specificity of the MHC1 staining was confirmed in β2‐microglobulin‐deficient mice, which lack normal cell surface MHC1‐IR. MHC1‐IR was particularly strong on phagocytic microglia, induced by delayed neuronal cell death, and correlated with the induction of mRNA for tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, and interferon‐γ and the influx of T lymphocytes. Mice with severe combined immunodeficiency (scid), lacking T and B cells, showed an increase in the number of MHC1‐positive nodules but no significant effect on overall MHC1‐IR. Transgenic deletion of the IL1 receptor type I, or the interferon‐γ receptor type 1 subunit, did not affect the microglial MHC1‐IR. However, a combined deletion of TNF receptors 1 and 2 (TNFR1&2‐KO) led to a decrease in microglial MHC1‐IR and to a striking absence of the phagocytic microglial nodules. Deletion of TNFR2 (p75) did not have an effect; deletion of TNFR1 (p55) reduced the diffuse microglial staining for MHC1‐IR but did not abolish the MHC1+ microglial nodules. In summary, neural injury leads to the induction of MHC1‐IR on the activated, phagocytic microglia. This induction of MHC1 precedes the interaction with the immune system, at least in the facial motor nucleus model. Finally, the impaired induction of these molecules, up to now, only in the TNFR‐deficient mice underscores the central role of TNF in the immune activation of the injured nervous system. J. Comp. Neurol. 470:382–399, 2004. © 2004 Wiley‐Liss, Inc.
Cell Shape Normalization, Dendrite Orientation, and Melanin Production of Normal and Genetically Altered (Haploinsufficient NF1)‐Melanocytes by Microstructured Substrate Interactions
Authors: Jungbauer Simon , Kemkemer Ralf , Gruler Hans , Kaufmann Dieter , Spatz Joachim P.
Published: February 2004

Little is known about how functional regulation failure in genetically altered cells is influenced by topographical confinement of cells, a situation often present in tissues in vivo. We used cultured melanocytes derived from human skin samples as a model system for such investigations. Normal melanocytes have a very well defined shape consisting of a cell body and two dendrites arranged 180° relative to each other. In contrast, neurofibromin 1‐melanocytes (NF1‐melanocytes) have up to a 50 % reduction of neurofibromin 1, which results in an altered morphology that can be easily measured. NF1‐melanocytes deviate from the defined structure of normal melanocytes by forming more than two dendrites per cell. We show that morphology consequences of genetically altered melanocytes can be canceled if cells interact with substrates microstructured by stripes that apply mechanophysical signals in the form of physical topography. The strength of the mechanophysical signal was varied systematically by increasing the height of the microstructures. Melanocytes respond to surface topographical features that are larger than 50 nm and have lateral confinements smaller 4 μm. The response of normal and NF1‐melanocytes to different topographies was analyzed quantitatively by determining density distributions for the number of dendrites per cell, the angles between dendrites, and the orientation imprinted in the substrate. The synthesis of melanin, a pigment produced by melanocytes, differs in the case of genetically altered NF1‐ and normal melanocytes. In both cases, the interaction with microstripes enhanced melanin production significantly. This enhanced melanin production is speculated to be caused by the mechanical stabilization of the dendrites by substrate guidance.
Frequency‐Switched Single‐Transition Cross‐Polarization: A Tool for Selective Experiments in Biomolecular NMR
Authors: Ferrage Fabien , Eykyn Thomas R. , Bodenhausen Geoffrey
Published: February 2004

Frequency‐switched single‐transition cross‐polarization (FS‐ST‐CP) provides a versatile tool for selective coherence transfer in heteronuclear NMR of biomolecules such as proteins and nucleic acids. This type of coherence transfer is spin‐state‐selective and can therefore benefit from the extension of the life‐times of selected coherences due to partial cancellation of interfering relaxation mechanisms. The limits of the selectivity of the transfer are discussed by theory and illustrated by experiment. The methods are particularly efficient to obtain quantitative structural and dynamic information for selected residues in medium‐sized nitrogen‐15 or carbon‐13 labeled macromolecules.
Cluster Assembled Nanostructures: Designing Interface Properties
Authors: Kaiser Bernhard , Stegemann Bert
Published: February 2004

Overlayer structures can be formed on surfaces by the deposition of preformed clusters from the gas phase containing from only a few up to a few hundred atoms. By this method, nanostructures with novel chemical and physical properties can be stabilized. This article presents the results obtained using the simple molecular cluster Sb4 as the precursor for deposition and nanoparticle assembly on various surfaces, and under various conditions. A rich variety of phenomena is observed and discussed.
Crystal growth and investigation of CuAlxGa1−xTe2 solid solutions
Authors: Bodnar I. V. , Victorov I. A. , Dabranski V. M.
Published: February 2004

Alloys of the CuGaTe2‐CuAlTe2 system have been synthesized by the one‐temperature method and homogenized by annealing. It was established for the first time by X‐ray and DTA methods that a continuous row of solid solutions is formed in the system. Large block crystals of CuAlxGa1−xTe2 solid solutions have been grown by the Bridgman method (horizontal version). Measurements of density, microhardness and thermal expansion have been carried out on the grown crystals. It has been established, that the density and thermal expansion coefficients are changed linearly with composition, microhardness has a maximum at x = 0.6. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Broadband consumer electronics networking and automation
Authors: Zahariadis Th. , Pramataris K.
Published: February 2004

Although a critical mass of households worldwide have access to the information superhighway, the broadband consumer networking and automation market is still evolving very slowly. Two reasons may be identified for this delay. The first one is related to the lack of broadband home data networks. Consumer electronics networks either do not exist at all or they are not able to support multimedia communications. The second reason is the large variety of ad hoc consortia or (un‐)authorized standardization bodies that have been defining independent, in many cases non‐interoperable specifications for residential networks. In this paper, we analyse and compare some of the most widely accepted, foreseen or advanced current and future broadband consumer electronics networking technologies able to support home automation and multimedia in‐home appliances. Technologies and standards are categorized in three groups based on their physical medium requirements. Moreover, we discuss technologies that are independent of the lower layers, and aim to provide convergence between multiple in‐home and access networks. Copyright © 2004 John Wiley & Sons, Ltd.
Ant based probabilistic routing with pheromone and antipheromone mechanisms
Authors: Sandalidis Harilaos G. , Mavromoustakis Constandinos X. , Stavroulakis Peter
Published: February 2004

Using the idea of probabilistic routing, calls in an ant based decentralized scheme are not routed according to the largest probabilities in the pheromone tables but randomly according to these probabilities. This principle can be particularly helpful in order to further minimize possible node congestion problems. An additional incorporation of the antipheromone mechanism in the operation of artificial ants helps in better biasing the network. This paper examines the behaviour of such a routing scheme using a proper set of suitable metrics. Copyright © 2004 John Wiley & Sons, Ltd.
Limiter discriminator detection of narrow‐band duobinary FSK in a land mobile channel
Authors: Hasan Omar M. , Hiasat Ahmad
Published: February 2004

Error rates (BER) for narrow‐band duobinary FM with discriminator detection and integrate and dump (LDI) post‐detection filtering in land mobile channel characterized by fading and Doppler frequency shift are obtained. The fading process is assumed to be much slower than data rate, allowing the fading process to be analysed in a quasistatic manner as it passes through the narrow‐band filter. A simulation model was constructed using the signal processing simulator, and the simulated error rate results are shown to agree well with the calculated error rate results. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of Titanium in Water Solutions
Authors: Mlakar Marina
Published: February 2004

Titanium(IV) dissolved in water solution can be successfully determined using adsorptive cathodic stripping square‐wave voltammetry in the presence of the mixed ligand system acetylacetone – lumazin (2,4‐dihydoxypteridin) maintaining pH at about 6. The method is additionally very sensitive due to the possibility of variation of square‐wave voltammetric parameters such as frequency and/or amplitude. The reduction peak of the titanium mixed ligand complex was detected at the potential of −1.49 V (vs. Ag/AgCl) and a limit of detection was found to be 0.4 nM with the accumulation time of 20 minutes at the potential of −1.2 V in the UV‐irradiated artificial seawater. Interferences of other trace metal ions and surface‐active substances were investigated as well.
Formation of Levan from Raffinose by Levansucrase of Zymomonas mobilis
Authors: Andersone I. , Auzina L. , Vigants A. , Mutere O. , Zikmanis P.
Published: February 2004

Levansucrase (EC 2.4.1.10.) of Zymomonas mobilis 113S can perform the polymerisation of fructose moiety from raffinose to levan concomitantly with a release of non‐catabolised melibiose into the medium. The kinetic parameters of the levansucrase‐catalysed reaction provide even higher reaction velocities on raffinose as compared to sucrose, particularly at low substrate concentrations. A decreased value in the number of the average molecular mass (Mn = 1693 kDa), an increased intrinsic viscosity (η = 49.47 cm3/g), and a diminished Huggin's constant (K' = 0.67) are intrinsic to the levan synthesis from raffinose, indicating certain structural peculiarities compared to a polysaccharide obtained from sucrose (Mn = 1851 kDa, [η] = 42.47 cm3/g, K' = 1.21).
Effects of Plant Growth Promoting Rhizobacteria (PGPRs) on the Biological Nitrogen Fixation, Nodulation, and Growth of Lupinus albus l. cv. Multolupa
Authors: Lucas García J. A. , Probanza A. , Ramos B. , Colón Flores J.J. , Gutiérrez Mañero F.J.
Published: February 2004

The effects of five plant growth promoting rhizobacteria on the biological nitrogen fixation (BNF), nodulation, and growth promotion of plants of Lupinus albus cv. Multolupa were investigated. The plants were selected for their capacity to use 1‐aminocyclopropane‐1‐carboxylic acid (ACC) as the sole source of nitrogen. Four strains belonged to the genus Pseudomonas (Luc 1, Luc 2, Luc 3, and Luc 4) and one (Luc 5) belonged to the genus Bacillus. Three patterns of inoculation were examined. In the first pattern, PGPRs were inoculated seven days before being inoculated with B. japonicum. In the second pattern, PGPRs and B. japonicum were co‐inoculated, and in the last pattern, PGPRs were inoculated seven days after being inoculated with B. japonicum. The plants were sampled 30 and 45 days after being inoculated with B. japonicum (T1 and T2). In the first pattern of inoculation, Luc 5 significantly increased the biological nitrogen fixation compared to the control at the first sampling time, as did Luc 1 and Luc 4 at the second sampling time. In the second pattern of inoculation, Luc 5 negatively effected the biological nitrogen fixation at both sampling times. In the third pattern of inoculation, all PGPRs caused a decrease in the nitrogen content of the plants compared to the control. The results obtained according to the patterns of inoculation showed that the mechanisms of action of the effects and routes used by Gram‐negative and Gram‐positive strains were clearly different. Competition between PGPRs and B. japonicum, competition for the niches in the rhizoplane, production of auxins, and induction of systemic resistance (ISR) by the production of siderophores or by lipopolysaccharides present in the outer membrane (LPS) are discussed as probable reasons for the effects observed.
Growth on Phenol at Chemostress Levels Amplifies the Expression of the Phenol Degradation Pathway in Acinetobacter calcoaceticus
Authors: Benndorf D. , Loffhagen N. , Härtig C. , Babel W.
Published: February 2004

Bacteria often use pollutants as sole carbon and energy sources. However, if they are toxic and the concentrations are high these compounds inhibit growth, and eventually poison the biocatalysts. In order to identify mechanisms contributing to stability, the protein patterns of Acinetobacter calcoaceticus during growth on potentially toxic phenol were analysed using two‐dimensional gel electrophoresis. Enzymes involved in the catabolism or assimilation of phenol, such as phenol monooxygenase and catechol 1,2‐dioxygenase, were induced at a more than twofold level in response to long‐term exposure to high concentrations of the compound serving as the sole carbon and energy source. This would have clear adaptive benefits, since increased rates of consumption of phenol would reduce the susceptibility of Acinetobacter calcoaceticus to phenol poisoning. In contrast, transient induction of only one heat shock protein and one oxidative stress protein was detected during long‐term exposure to high concentrations of phenol.
A new header compression scheme for TCP streams in IP based wireless networks
Authors: Boggia Gennaro , Camarda Pietro , Petrizzelli Sandro , Squeo Vito G.
Published: February 2004

The current trend in the telecommunication world is the proposal of a universal telecommunication system deriving from the convergence between mobile telephony and data transmission. To achieve such a convergence in an efficient way, it is presumably necessary to utilize a network platform totally based on TCP/IP architecture (an ‘All‐IP Network’). However, the encapsulation process of TCP/IP wastes a substantial part of the radio channel bandwidth for the transmission of control information (header) that does not have any specific function at radio level. Since this bandwidth is generally the most expensive and limited resource for wireless networks, it is necessary to adopt a header compression scheme that can reduce the protocol overhead while working efficiently and robustly under noisy links with time‐variant BER conditions. In this paper, a new header compression scheme for TCP streams as a specific header compression profile within the IETF ROHC (robust header compression) framework is proposed and analyzed through simulations exploiting network simulator (ns‐2). The proposed scheme, compliant with IETF requirements for TCP/IP header compression, is based on the distinct management of data and acknowledgment (ACK) streams associated with the TCP connection and exploits a robust header encoding technique for reducing the effect of error propagation. The results obtained, in terms of throughput, overhead and goodput, are reported as a function of bandwidth and BER. A comparison with the results obtained without compression allows us to evaluate the performance of the proposed compression scheme in a realistic and dynamic environment. Copyright © 2004 AEI
Impact of transmitter and receiver filtering on the phase and error floor of MSK signal indoor transmission
Authors: Lipovac Vlatko
Published: February 2004

In this paper, the impact of the transmitter/receiver filtering (in tandem with multipath propagation) on the phase‐shift of the minimum shift keying (MSK) signal transmitted over a mobile radio channel with small time dispersion has been modeled in order to analytically investigate the validity of the closed‐form general expression for the error floor—for various filter bandwidths of interest (e.g. DECT). Theoretical conclusions are supported by computer simulation results. Copyright © 2004 AEI
Expression of a member of tumor necrosis factor receptor superfamily, TROY, in the developing olfactory system
Authors: Hisaoka Tomoko , Morikawa Yoshihiro , Kitamura Toshio , Senba Emiko
Published: February 2004

TROY is a recently identified member of the tumor necrosis factor (TNF) receptor superfamily. We have previously reported that TROY induces the activation of nuclear factor κB via TNF receptor‐associated factor 2, 5, and 6, and is strongly expressed in the developing central nervous system, including the olfactory bulb. In this study, we investigated the detailed cellular characterization of TROY‐expressing cells in the developing olfactory system of mice using in situ hybridization and immunohistochemistry. Both mRNA and protein of TROY were first detected in the olfactory nerve layer (ONL) of the olfactory bulb at embryonic day 13.5. During late embryogenesis, TROY expression was most intense in the inner ONL (ONL‐i). In the postnatal olfactory bulb, TROY‐expressing cells were also detected in the glomerular layer (GL), in addition to the ONL‐i. The double‐immunofluorescence method demonstrated that TROY was expressed in olfactory ensheathing cells (OECs) of the ONL‐i, which were positive for neuropeptide Y (NPY), but neither S‐100 nor p75 low‐affinity nerve growth factor receptor. Some TROY‐expressing cells in the ONL‐i were observed with the astrocyte‐like phenotype (GFAP+/NPY−). In addition, TROY was also detected in GFAP+ glial cells of the GL. Thus, TROY was expressed in some specific subsets of glial cells in the olfactory bulb, including OECs, suggesting that TROY may play some roles in the developing and adult olfactory system. © 2004 Wiley‐Liss, Inc.
Divergent consequences arise from metallothionein overexpression in astrocytes: Zinc buffering and oxidant‐induced zinc release
Authors: Malaiyandi Latha M. , Dineley Kirk E. , Reynolds Ian J.
Published: February 2004

Excessive accumulation of the heavy metal zinc is cytotoxic. As a consequence, cellular vulnerability to zinc‐induced injury may be regulated by the abundance of proteins that maintain intracellular free zinc concentrations ([Zn2+]i). In this study, we overexpressed the zinc‐binding protein metallothionein‐II (MT) in astrocytes to assess its impact as (1) an acute zinc buffering mechanism, and (2) an oxidant‐releasable zinc pool. Overexpression of MT in primary astrocyte cultures was accomplished using an adenoviral vector. Using the zinc‐sensitive fluorescent indicator mag‐fura‐2, we monitored [Zn2+]i after stimulating zinc influx or oxidant treatment. With MT overexpression, we observed an acute buffering effect manifested as a dampening of stimulus‐induced increases in [Zn2+]i. In contrast, we also saw enhanced zinc release with application of the sulfhydryl oxidizing agent 2,2′‐dithiodipyridine. These results indicate that overexpression of a zinc‐binding protein can quickly diminish [Zn2+]i following zinc influx, but elevate [Zn2+]i under conditions of oxidative stress, providing protective yet potentially endangering effects. © 2003 Wiley‐Liss, Inc.
Electrophysiological and molecular evidence of L‐(Cav1), N‐ (Cav2.2), and R‐ (Cav2.3) type Ca2+ channels in rat cortical astrocytes
Authors: D'Ascenzo Marcello , Vairano Mauro , Andreassi Catia , Navarra Pierluigi , Azzena Gian Battista , Grassi Claudio
Published: February 2004

Changes in intracellular Ca2+ levels are an important signal underlying neuron‐glia cross‐talk, but little is known about the possible role of voltage‐gated Ca2+ channels (VGCCs) in controlling glial cell Ca2+ influx. We investigated the pharmacological and biophysical features of VGCCs in cultured rat cortical astrocytes. In whole‐cell patch‐clamp experiments, L‐channel blockade (5 μM nifedipine) reduced Ba2+ current amplitude by 28% of controls, and further decrease (32%) was produced by N‐channel blockade (3 μM ω‐conotoxin‐GVIA). No significant additional changes were observed after P/Q channel blockade (3 μM ω‐conotoxin‐MVIIC). Residual current (36% of controls) amounted to roughly the same percentage (34%) that was abolished by R‐channel blockade (100 nM SNX‐482). Electrophysiological evidence of L‐, N‐, and R‐channels was associated with RT‐PCR detection of mRNA transcripts for VGCC subunits α1C (L‐type), α1B (N‐type), and α1E (R‐type). In cell‐attached recordings, single‐channel properties (L‐currents: amplitude, −1.21 ± 0.02 pA at 10 mV; slope conductance, 22.0 ± 1.1 pS; mean open time, 5.95 ± 0.24 ms; N‐currents: amplitude, −1.09 ± 0.02 pA at 10 mV; slope conductance, 18.0 ± 1.1 pS; mean open time, 1.14 ± 0.02 ms; R‐currents: amplitude, −0.81 ± 0.01 pA at 20 mV; slope conductance, 10.5 ± 0.3 pS; mean open time, 0.88 ± 0.02 ms) resembled those of corresponding VGCCs in neurons. These novel findings indicate that VGCC expression by cortical astrocytes may be more varied than previously thought, suggesting that these channels may indeed play substantial roles in the regulation of astrocyte Ca2+ influx, which influences neuron‐glia cross‐talk and numerous other calcium‐mediated glial‐cell functions. © 2003 Wiley‐Liss, Inc.