Design and Characterization of a New pVII Combinatorial Phage Display Peptide Library for Protease Substrate Mining Using Factor VII Activating Protease (FSAP) as Model

We describe a novel, easy and efficient combinatorial phage display peptide substrate-mining method to map the substrate specificity of proteases. The peptide library is displayed on the pVII capsid of the M13 bacteriophage, which renders pIII necessary for infectivity and efficient retrieval, in an unmodified state. As capture module, the 3XFLAG was chosen due to its very high binding efficiency to anti-FLAG mAbs and its independency of any post-translational modification. This library was tested with Factor-VII activating protease (WT-FSAP) and its single-nucleotide polymorphism variant Marburg-I (MI)-FSAP. The WT-FSAP results confirmed the previously reported Arg/Lys centered FSAP cleavage site consensus as dominant, as well as reinforcing MI-FSAP as a loss-of-function mutant. Surprisingly, rare substrate clones devoid of basic amino acids were also identified. Indeed one of these peptides was cleaved as free peptide, thus suggesting a broader range of WT-FSAP substrates than previously anticipated.     

A probabilistic model for cleavage fracture with a length scale--parameter estimation and predictions of stationary crack experiments

This study presents a large experimental investigation in the transition temperature region on a modified A508 steel. Tests were carried out on single-edge-notch-bend specimens with three different crack depth over specimen width ratios to capture the strong constraint effect on fracture toughness. Three test temperatures were considered, covering a range of 85 °C. All specimens failed by cleavage fracture prior to ductile tearing. A recently proposed probabilistic model for the cumulative failure by cleavage was applied to the comprehensive sets of experimental data. This modified weakest link model incorporates a length scale, which together with a threshold stress reduce the scatter in predicted toughness distributions as well as introduces a fracture toughness threshold value. Model parameters were estimated by a robust procedure, which is crucial in applications of probabilistic models to real structures. The conformity between predicted and experimental toughness distributions, respectively, were notable at all the test temperatures.     

Ab<Emphasis Type="Italic"> initio</Emphasis> investigation of boron diffusion paths in germanium

Boron is observed to diffuse very slowly in germanium, as opposed to its behaviour in silicon where it exhibits Transient Enhanced Diffusion effects in implanted samples. As a result of this slow diffusion, boron is a very stable dopant, allowing devices to be created with very well-defined doping regions. To understand this superior performance, calculations were performed on a variety of boron diffusion paths, within vacancy and interstitial mediated methods. It was found that the vacancy mediated diffusion which is associated with the fast diffusion of many other species in germanium exhibits a total barrier of 5.8 eV. Interstitial-mediated diffusion had a total barrier for migration of 3.4 eV in the neutral and singly negative charge states, 3.2 eV for the positive charge state, but a formation barrier of 4.1 eV. Thus the barrier for interstitial-mediated diffusion is dominated by the formation energy of the self-interstitial.     

Distinction between artefactually shrunken and truly degenerated 'dark' neurons by in situ fixation with microwave irradiation

Dark, shrunken neurons frequently occur as artefacts in immersion fixed tissue. Perfusion fixation will prevent artefacts of this type. However, morphologically identical neurons have been described as truly degenerated cells in perfusion fixed brains in various pathological conditions. Since adequate perfusion is difficult to obtain in some pathological conditions, the question still remains whether the dark neurons found in some of these situations are true in vivo phenomena or artefacts caused by inadequate fixation. In the present study rat brains with cryogenic lesions were fixed in situ by microwave irradiation. With this method no artefactually changed dark neurons were observed in the normal parts of the brains. In the cryogenic lesions, however, a narrow rim of dark, shrunken neurons occurred adjacent to the normal cortex. This zone was identical to that observed in perfusion fixed tissue. Since inadequate fixation due to uneven perfusion of the damaged tissue is prevented with this method, we suggest that the neuronal changes represent true in vivo phenomena. Fixation with microwave irradiation can thus be used to differentiate between artefactually changed and truly degenerated dark neurons in various pathological conditions.     

Psychometric considerations in the dimensional analysis of subjective picture quality

A discussion of the factors involved in the subjective perception of television picture quality is presented. Much of the work in this field is cited, and it is concluded that future work needs to consider a broader range of variables than has been looked at so far.     

Nonlinear black-box modeling in system identification: a unified overview

A nonlinear black-box structure for a dynamical system is a model structure that is prepared to describe virtually any nonlinear dynamics. There has been considerable recent interest in this area, with structures based on neural networks, radial basis networks, wavelet networks and hinging hyperplanes, as well as wavelet-transform-based methods and models based on fuzzy sets and fuzzy rules. This paper describes all these approaches in a common framework, from a user's perspective. It focuses on what are the common features in the different approaches, the choices that have to be made and what considerations are relevant for a successful system-identification application of these techniques. It is pointed out that the nonlinear structures can be seen as a concatenation of a mapping form observed data to a regression vector and a nonlinear mapping from the regressor space to the output space. These mappings are discussed separately. The latter mapping is usually formed as a basis function expansion. The basis functions are typically formed from one simple scalar function, which is modified in terms of scale and location. The expansion from the scalar argument to the regressor space is achieved by a radial- or a ridge-type approach. Basic techniques for estimating the parameters in the structures are criterion minimization, as well as two-step procedures, where first the relevant basis functions are determined, using data, and then a linear least-squares step to determine the coordinates of the function approximation. A particular problem is to deal with the large number of potentially necessary parameters. This is handled by making the number of ‘used’ parameters considerably less than the number of ‘offered’ parameters, by regularization, shrinking, pruning or regressor selection.     

Platyphylloside: Metabolism and digestibility reductionin vitro

The metabolism of platyphylloside [(5S)-5-hydroxy-1,7-bis-(4-hydroxyphenyl)-3-heptanone-5-O--d-glucopyranosidel]—known to reduce digestibility—was studiedin vitro in sheep rumen liquor. Platyphylloside is hydrolyzed to 5-hydroxy-3-platyphyllone [(5S)-5-hydroxy-1,7-bis-(4-hydroxyphenyl)-3-heptanone], which is reduced to centrolobol [1,7-bis-(4-hydroxyphenyl)-3-heptanol], via 3-platyphyllone [7-bis-(4-hydroxyphenyl)-3-heptanone]. The digestibility-reducing effect was shown to be correlated with the concentration of centrolobol.     

The content and composition of sterols and sterol esters in low erucic acid rapeseed (Brassica napus)

The low temperature crystallization technique for the enrichment of “minor” components, such as sterols and sterol esters, from vegetable oils was applied to low erucic acid rapeseed oils. The recovery of free sterols and sterol esters was estimated by use of¹⁴C-cholesterol and¹⁴C-cholesterol oleate. 80% of the free sterols and 45% of the sterol esters were recovered in the liquid fraction, while in two studies total recoveries were 95% and 99%, respectively. This technique showed some selectivity toward the sterol bound fatty acids when compared to direct preparative thin layer chromatography (TLC) of the crude oil. Gas liquid chromatography (GLC) analysis of the free and esterified sterols as TMS-derivatives showed very little selectivity in the enrichment procedure. The fatty acid patterns of the sterol esters demonstrated, however, a preference in the liquid fraction for those sterol esters which have a high linoleic and linolenic acid content. The content of free sterols was 0.3–0.4% and that of sterol esters 0.7–1.2% of the rapeseed oils in both winter and summer types of low erucic acid rapeseed (Brassica napus) when the lipid classes were isolated by direct preparative TLC of the oils. The free sterols in the seven cultivars or breeding lines analyzed were composed of 44–55% sitosterol, 27–36% campesterol, 17–21% brassicasterol, and a trace of cholesterol. The esterified sterols were 47–57% sitosterol, 36–44% campesterol, 6–9% brassicasterol, and traces of cholesterol and Δ5-avenasterol. The fatty acid patterns of these esters were characterized by ca. 30% oleic acid and ca. 50% linoleic acid, whereas these acids constitute 60% and 20%, respectively, of the total fatty acids in the oil. Little or no variation in sterol and sterol ester patterns with locality within Sweden was observed for the one cultivar of summer rapeseed investigated by the low temperature crystallization technique.     

An empirical study of control logic specifications for programmable logic controllers

This paper presents an empirical study of control logic specifications used to document industrial control logic code in manufacturing applications. More than one hundred input/output related property specifications from ten different reusable function blocks were investigated. The main purpose of the study was to provide understanding of how the specifications are expressed by industrial practitioners, in order to develop new tools and methods for specifying control logic software, as well as for evaluating existing ones. In this paper, the studied specifications are used to evaluate linear temporal logic in general and the specification language ST-LTL, tailored for functions blocks, in particular. The study shows that most specifications are expressed as implications, that should always be fulfilled, between input and output conditions. Many of these implications are complex since the input and output conditions may be mixed and involve sequences, timer issues and non-boolean variables. Using ST-LTL it was possible to represent all implications of this study. The few non-implication specifications could be specified in ST-LTL as well after being altered to suit the specification language. The paper demonstrates some advantages of ST-LTL compared to standard linear temporal logic and discusses possible improvements such as support for automatic rewrite of complex specifications.     

Variations in the composition of sterols,tocopherols and lignans in seed oils from fourSesamum species

Seeds from different collections of cultivatedSesamum indicum Linn and three related wild species [specifically,S. alatum Thonn.,S. radiatum Schum & Thonn. andS. angustifolium (Oliv.) Engl.] were studied for their oil contents and fatty acid composition of the total lipids. The oils from wild seeds were characterized by higher percentages of unsaponifiables (4.9, 2.6 and 3.7%, respectively) compared toS. indicum (1.4–1.8%), mainly due to their high contents of lignans. Total sterols accounted forca. 40, 22, 20 and 16% of the unsaponifiables of the four species, respectively. The four species were different in the relative percentages of the three sterol fractions (the desmethyl, monomethyl and dimethyl sterols) and in the percentage composition of each fraction. Campesterol, stigmasterol, sitosterol and Δ⁵-avenasterol were the major desmethyl sterols, whereas obtusifoliol, gramisterol, cycloeucalenol and citrostandienol were the major monomethyl sterols, and α-amyrin, β-amyrin, cycloartenol and 24-methylene cycloartanol were the main dimethyl sterols in all species. Differences were also observed among the four species in sterol patterns of the free sterols compared to the sterol esters.Sesamum alatum contained less tocopherols (210–320 mg/kg oil), andS. radiatum andS. angustifolium contained more tocopherols (ca. 750 and 800 mg/kg oil, respectively) than didS. indicum (490–680 mg/kg oil). The four species were comparable in tocopherol composition, with γ-tocopherol representing 96–99% of the total tocopherols. The four species varied widely in the identity and levels of the different lignans. The percentages of these lignans in the oils ofS. indicum were sesamin (0.55%) and sesamolin (0.50%).Sesamum alatum showed 1.37% of 2-episesalatin and minor amounts of sesamin and sesamolin (0.01% each).Sesamum radiatum was rich in sesamin (2.40%) and contained minor amounts of sesamolin (0.02%), whereS. angustifolium was rich in sesangolin (3.15%) and also contained considerable amounts of sesamin (0.32%) and sesamolin (0.16%).