Studies of malformation syndromes of man XXIX: the Wiedemann-Beckwith syndrome. Clinical, genetic and pathogenetic studies of 12 cases

This report describes 12 patients with the Wiedemann-Beckwith syndrome (WBS), including 6 familial cases from 2 families. The clinical manifestations do not allow for a differentiation between familial and sporadic cases. Consistent morphologic features include organomegaly, cytomegaly and nucleomegaly. The pathogenetic process may involve few or many organs and tissues and may represent a nuclear/mitotic dysfunction. Clinically, the manifestations are hyperplasia, hypoplasia, dysplasia, neoplasia and defects in differentiation. Secondary functional disturbances are at times prominent. The differential diagnosis of the WBS includes 1) the Wilm's tumor (WT)-aniridia syndrome: 2) the "tumor-hypertrophy syndrome" which includes WT, adenocortical tumors or hepatoblastoma; 3) the WT-pseudohermaphroditism syndrome; and 4) the "tumor-nevus syndrome" with or without malformations (particularly duplications) of the urinary tract. The latter two conditions are apparently not associated with hemihypertrophy. Familial occurrence suggests that some cases of the WBS may be due to delayed mutation. Carriers of the premutated allele appear to belong to two classes: those with a high risk of producing affected offspring and those who transmit the premutated allele but have no affected offspring.     

Oxidative oil stability using volatiles methodology

Journal of the American Oil Chemists' Society -     

Impact of dissolved wastewater constituents on peroxidase‐catalyzed treatment of phenol

The impact of dissolved wastewater constituents on the treatment of synthetic phenol solutions using horseradish peroxidase (HRP) and hydrogen peroxide was investigated under a variety of reaction conditions. The constituents studied included various inorganic salts, organic compounds and heavy metals. Higher H₂O₂ doses were required to treat phenol in the presence of sodium sulfite, thiosulfate and sulfide; however, enhanced levels of phenol conversion were achieved once sufficient H₂O₂ was supplied. Sulfide and cyanide inhibited phenol transformation. The inhibition of sulfide was overcome by supplying sufficient H₂O₂ to oxidize the sulfide to sulfur. However, increasing the H₂O₂ dose was ineffective in attempting to overcome the strong inhibiting effect of cyanide. Among the heavy metal ions tested, only Mn(II) substantially inhibited phenol removal when it was present at a concentration of 1 mmol dm^?3. The presence of inorganic salts including NaCl, CaCl₂, MgCl₂, NH₄Cl and (NH₄)₂SO₄ reduced phenol conversion as compared with the treatment in distilled‐deionized water. This can be attributed to the increased ionic strength of the solution. © 2002 Society of Chemical Industry     

Surface texturing of Mo–V–Te–Nb–O x selective oxidation catalysts

The paper concentrates on the study of Mo–V–Te–Nb oxide mixtures by electron microscopy combined with catalytic investigation of these materials in the partial oxidation of propane. Surface texturing of catalyst particles composed of two phases referred to in the literature as M1 and M2 is revealed by high-resolution transmission electron microscopy of high performing catalysts. The chemical composition of the catalyst surface is modified by treatment in water to obtain a significant increment in yield of acrylic acid. A chemical realization of the site isolation concept recurring on a supramolecular arrangement of catalyst and reactant rather than on atomic site isolation is suggested. A complex Mo–V–Te–Nb–O _x precursor phase carries nanoparticles made from a network of oxoclusters active as catalyst for the conversion of propane to acrylic acid. The designed synthesis of the multi-element oxide bulk and of the surface structure with a different composition than the precursor phase improved the performance by a factor of 4.     

Branching and molecular weight distribution of polyethylene SRM 1476

A method of determining the distribution of branching in a polymer is developed employing limiting viscosity numbers (intrinsic viscosity), gel permeation chromatography (GPC), and absolute molecular weight determinations of fractions of the whole polymer. A molecular weight calibration of the GPC column set is first determined empolying these fractions. From the limiting viscosity number measurements of these fractions and their molecular weight distribution determined from the GPC chromatogram, the viscosity–molecular weight relationship is determined by a nonlinear least-squares fitting procedure. For the same molecular weight, the limiting viscosity number of the branched polymer is less than the limiting viscosity number of the linear polymer. From the ratio of the two, the number of branches per unit molecular weight of the branched polymer is calculated. The method was applied to SRM 1476, the standard reference branched polyethylene issued by the National Bureau of Standards. The branching density for the constituents of SRM 1476 rise from zero at molecular weights less than 10,000 to about 6 to 8×10^?5 at molecular weights of 50,000 and above. The branching of SRM 1476 was also determined by the method of Drott and Mendelson, giving a result in fair agreement with the above method.     

Agglomeration and breakage of nanoparticles in stirred media mills—a comparison of different methods and models

The increasing industrial demand for nanoparticles challenges the application of stirred media mills to grind in the sub-micron size range. It was shown recently [Mende et al., 2003. Mechanical production and stabilization of submicron particles in stirred media mills. Powder Technology 132, 64-73] that the grinding behavior of particles in the sub-micron size range in stirred media mills and the minimum achievable particle size is strongly influenced by the suspension stability and thus the agglomeration behavior of the suspension. Therefore, an appropriate modeling of the process must include a superposition of the two opposing processes in the mill i.e., breakage and agglomeration which can be done by means of population balance models. Modeling must now include the influence of colloidal surface forces and hydrodynamic forces on particle aggregation and breakup. The superposition of the population balance models for agglomeration and grinding with the appropriate kernels leads to a system of partial differential equations, which can be solved in various ways numerically. Here a modified h-p Galerkin algorithm which is implemented in the commercially available software package PARSIVAL developed by CiT (CiT GmbH, Rastede, Germany) and the moment methodology according to [Diemer and Olsen, 2002a. A moment methodology for coagulation and breakage problems: Part I—analytical solution of the steady-state population balance. Chemical Engineering Science 57 (12), 2193-2209; Diemer and Olsen, 2002b. A moment methodology for coagulation and breakage problems: Part II—moment models and distribution reconstruction. Chemical Engineering Science 57 (12), 2211-2288] are used and compared to explicit data on alumina. This includes a comparison of the derived particle size distributions, moments and its accuracy depending on the starting particle size distribution and the used agglomeration and breakage kernels. Finally, the computational effort of both methods in comparison to the prior mentioned parameters is evaluated in terms of practical application.     

Simulation of microstructure development in injection molding of engineering plastics

Mathematical models were developed to predict the various microstructural properties, including birefringece, residual stress, and density distributions, in the freely quenched compression molded samples as well as in the injection molded samples. To model the birefringence distribution in the injection molded samples, the BKZ type integral constitutive equation was employed to account for the nonisothermal stress relaxation, which takes place during the cooling stage of the molding cycle. The predicted birefringence agreed well with the experimental data near the mold walls. The residual stress distribution was modeled by the existing thermoelastic theory. The residual thermal stress distribution in the freely quenched samples was predicted very well by the model. However, the predicted residual thermal stresses in the injection molded samples were much larger than the measured ones. A phenomenological model to predict the density distribution in injection molded sample is proposed by including the effects of both cooling rate and the pressure on the density development. The predicted results agreed well with the experimental data.     

Orthogonal Graph Drawing with Flexibility Constraints

Traditionally, the quality of orthogonal planar drawings is quantified by either the total number of bends, or the maximum number of bends per edge. However, this neglects that in typical applications, edges have varying importance. In this work, we investigate an approach that allows to specify the maximum number of bends for each edge individually, depending on its importance. We consider a new problem called FlexDraw that is defined as follows. Given a planar graph G=(V,E) on n vertices with maximum degree 4 and a function $\operatorname{flex}: E \longrightarrow\mathbb{N}_{0}$ that assigns a flexibility to each edge, does G admit a planar embedding on the grid such that each edge e has at most $\operatorname{flex}(e)$ bends? Note that in our setting the combinatorial embedding of G is not fixed. FlexDraw directly extends the problem β-embeddability asking whether G can be embedded with at most β bends per edge. We give an algorithm with running-time O(n ²) solving FlexDraw when the flexibility of each edge is positive. This includes 1-embeddability as a special case and thus closes the complexity gap between 0-embeddability, which is $\mathcal{NP}$ -hard to decide, and 2-embeddability, which is efficiently solvable since every planar graph with maximum degree 4 admits a 2-embedding except for the octahedron. In addition to the polynomial-time algorithm we show that FlexDraw is $\mathcal{NP}$ -hard even if the edges with flexibility 0 induce a tree or a union of disjoint stars.