Chaotic oscillator in wavelength: a new setup for investigatingdifferential difference equations describing nonlinear dynamics

A generator of chaos in wavelength is reported. It is formed by a wavelength-tunable laser diode with a time delayed feedback loop in which a wavelength nonlinear-linear device is introduced. The dynamical regime of wavelength emission thus obtained is ruled by a differential difference equation. Experimental results are compared with numerical simulations and with previous theoretical and experimental results     

Discrepancies between thyrotropin (TSH) measurement by four sensitive immunometric assays

A comparison of four different commercial immunometric thyrotropin (TSH) assays (Amerlite R TSH-30 Ultrasensitive assay from Kodak, BeriLux R hTSH from Behring Werke, Delfia R hTSH Ultra from Wallac and IMX R Ultrasensitive hTSH from Abbott) was made by measuring serum TSH in 81 consecutive patients referred to hospital for various reasons with a serum TSH less than 0.8 mlU/l in the IMX assay. The analytical and functional assay sensitivities of each of the assays were analysed. Even though three of the methods had a sensitivity corresponding to third generation assays, we could only demonstrate an overall agreement of serum TSH when comparing two of the kits. The measurements in Delfia Ultra and Berilux showed good agreement (P = 0.7, paired t-test and bias = 0.003 mIU/l), while the comparisons between the other assays showed different measurements (P < 0.00001, paired t-test and bias more than 0.07 mIU/l). Differences in the calibrators used in the assays might explain some of the discrepancy, although all methods were calibrated according to the same international standard. Also, differences in the specificity of the TSH monoclonal antibodies used in the assays might be an evident explanation and further studies of the specificity of the monoclonal antibodies are needed. An international collaborative study to clarify reasons for the differences between the TSH assays and to standardize the measurements is recommended.     

Responses of ligamentous fibroblasts to mechanical stimulation

Mechanical stimulation, as provided by physiotherapy or controlled motion is essentially the only factor able to improve anterior cruciate ligament (ACL) healing. We investigate the cellular effects of such stimulus. Two types of stimulations are applied on canine ACL fibroblasts: repetitive stretch of an elastomeric adhesion substrate and a laminar flow of culture media over the culture surface. Cell orientation, proliferation rate, synthesis and type of collagen as well as proteoglycans (PG) synthesis and hydrodynamic characteristics have been studied. According to our results, the fibroblasts tend to align perpendicularly to the deformation axis of their substrate, and along a laminar flow. The shear stress induced by the laminar flow does not modify significantly proliferation rate nor extracellular matrix synthesis. Substrate stretching however, increases proliferation rate, collagen synthesis, mostly type III, and PG synthesis, principally of small sizes. The characteristics of fibroblasts submitted to repeated deformation match those of fibroblasts from ligament scar tissues. Their orientation perpendicular to substratum deformation differs from the one usually encountered in the undamaged tissue: aligned on the ligament axis.     

Minimum cost design of RC beams using DCOC Part II: Beams with uniform cross-sections

The optimality criteria and numerical algorithms for DCOC are specialized in this part of the two-part paper to multispan structures each span of which is assumed to have a uniform section along its entire length. The steel ratio is allowed to vary freely along the length. Selfweight of the spans is also included in the equilibrium equation of the real system and in the optimality criteria.Section, equation, figure and table numbers continue from Part I.     

A method of calculating the compression deformation modulus of sandy and gravelly soils

A method based on use of Hardin's homogeneous model is proposed for calculation of the deformation modulus of noncohesive soils. Completely satisfactory correspondence between computed and experimental values of the deformation modulus of sands is demonstrated. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 2–5, July–August, 1994.     

Development of the bi-directional ultrasound system for base of tongue imaging

The use of conventional ultrasound systems to image the upper airway has been limited because ultrasound energy is attenuated by the air column. In an attempt to study upper airway geometry, we developed a computer controlled bi-directional ultrasound system which combines two conventional ultrasound devices with computer image processing to yield images of upper airway structures. Human studies and cadaver studies were performed to evaluate the system. Images acquired by the bi-directional ultrasound system were comparable to images from 3D volume rendered CT scans. This system may provide valuable data in the study of upper airway physiology and pathology.     

Successful pregnancies in the presence of spinal muscular atrophy: two case reports

We report two cases of successful pregnancy in women with chronic, infantile onset, or type II spinal muscular atrophy, both of whom delivered healthy, unaffected babies. The patients required concurrent management by a physiatrist, pulmonologist, and perinatologist throughout the pregnancy. Complications included recurrent urinary tract infections, dyspnea and worsening of pulmonary function, wheelchair seating and positioning problems, and musculoskeletal and low back pain. These problems resolved postpartum. One woman had vaginal delivery, the other had caesarean section, both of which were well-tolerated. Because of severe musculoskeletal deformity, pelvic assessment is necessary to determine the mode of delivery. The uterus has normal contractility and effective labor patterns can be established. Spinal/epidural anesthesia may be contraindicated because of spine deformity. The pregnancies had no deleterious effect on the progression of the disease in our patients, both of whom reported a positive experience with great personal fulfillment.     

A cdc2-like kinase associated with commitment to division in Paramecium tetraurelia

Cell division in higher eukaryotes is mainly controlled by p34cdc2 or related kinases and by other components of these kinase complexes. We present evidence that cdc2-like kinases also occur in Paramecium. Two polypeptides reacted with an antibody directed against the perfectly conserved PSTAIR region found in cdc2 kinases in other eukaryotes. Only the less abundant peptide bound to p13suc1 from Schizosaccharomyces pombe. Using centrifugal elutriation to select cells on the basis of size, we isolated highly synchronous Paramecium G1 cells. With this procedure, we demonstrated that the p13suc1-associated cdc2-like histone H1 kinase was activated before cell division at the point of commitment to division in Paramecium. Further, we show that Paramecium cdc2-like proteins occurred principally as monomers and that these monomers were active as histone H1 kinases in vitro.     

Automatic generation of IDEF0 models

This paper looks into a new area for knowledge-based system application, that of manufacturing modelling. Manual generation of IDEF0 models of manufacturing systems is time-consuming and inconsistent. However, the process can be automated to improve timeliness and consistency. In this paper, a knowledge-based manufacturing modelling system for the automatic generation of IDEF0 models is proposed. The system will not only greatly reduce the IDEF0 modelling time but will also eliminate the inconsistency problem of conventional IDEF0 modelling systems. The paper explains the knowledge-based approach and identifies the kinds of domain knowledge that are required for the construction of the knowledge-based manufacturing modelling system.     

A broadly cross-protective monoclonal antibody binding to Escherichia coli and Salmonella lipopolysaccharides

During the last decade, episodes of sepsis have increased and Escherichia coli has remained the most frequent clinical isolate. Lipopolysaccharides (LPS; endotoxin) are the major toxic and antigenic components of gram-negative bacteria and qualify as targets for therapeutic interventions. Molecules that neutralize the toxic effects of LPS are actively investigated. In this paper, we describe a murine monoclonal antibody (MAb; WN1 222-5), broadly cross-reactive and cross-protective for smooth (S)-form and rough (R)-form LPS. As shown in enzyme-linked immunosorbent assay and the passive hemolysis assay, WN1 222-5 binds to the five known E. coli core chemotypes, to Salmonella core, and to S-form LPS having these core structures. In immunoblots, it is shown to react with both the nonsubstituted core LPS and with LPS carrying O-side chains, indicating the exposure of the epitope in both S-form and R-form LPS. This MAb of the immunoglobulin G2a class is not lipid A reactive but binds to E. coli J5, an RcP+ mutant which carries an inner core structure common to many members of the family Enterobacteriaceae. Phosphate groups present in the inner core contribute to the epitope but are not essential for the binding of WN1 222-5 to complete core LPS. Cross-reactivity for clinical bacterial isolates is broad. WN1 222-5 binds to all E. coli clinical isolates tested so far (79 blood isolates, 80 urinary isolates, and 21 fecal isolates) and to some Citrobacter, Enterobacter, and Klebsiella isolates. This pattern of reactivity indicates that its binding epitope is widespread among members of the Enterobacteriaceae. WN1 222-5 exhibits biologically relevant activities. In vitro, it inhibits the Limulus amoebocyte lysate assay activity of S-form and R-form LPS in a dose-dependent manner and it neutralizes the LPS-induced release of clinically relevant monokines (interleukin 6 and tumor necrosis factor). In vivo, WN1 222-5 blocks endotoxin-induced pyrogenicity in rabbits and lethality in galactosamine-sensitized mice. The discovery of WN1 222-5 settles the long-lasting controversy over the existence of anti-core LPS MAbs with both cross-reactive and cross-protective activity, opening new possibilities for the immunotherapy of sepsis caused by gram-negative bacteria.