Juvenile hyaline fibromatosis

BACKGROUND: Juvenile hyaline fibromatosis (JHF) is rare disease of autosomal recessive inheritance. CASE REPORT: A 14-year old boy, born to consanguineous parents was admitted because he suffered from multiple tumors since the age of 5 years. These tumors were mobile, painful varying in size, located mainly on the head, the back, and extremities; they were associated with gingival overgrowth. Bone X-rays showed osteolytic lesions. The cognitive development was normal. Biopsy of tumors showed cords of spindle-shaped cells embedded in homogeneous eosinophilic matrix. The child was progressively disabled due to articular changes. Two of his brothers presented the same features. CONCLUSION: This new case of JHF confirms the severity of prognosis of such a fibromatosis presently considered as a hereditary disorder of collagen metabolism.     

CHARGE association: new associated anomalies

The extraction of impacted foreign bodies from the oesophagus is frequently performed using forceps under endoscopic guidance. We report the case of a 23-year-old prisoner who ingested a lump of cannabis resin which could not be removed from the upper oesophagus with forceps alone. We recommend the use of a Fogarty balloon catheter in conjunction with toothed forceps in such cases.     

Design-Operation of Multi-Hydropower Reservoirs: HBMO Approach

To illustrate and test the applicability and performance of the innovative honey-bee mating optimization (HBMO) algorithm in highly non-convex hydropower system design and operation, two problems are considered: single reservoir and multi-reservoir. Both hydropower problems are formulated to minimize the total present net cost of the system, while achieving the maximum possible ratio for generated power to installed capacity. The single hydropower reservoir problem is approached by the developed algorithm in 10 different runs. The first feasible solution was generated initially and later improved significantly and solutions converged to a near optimal solution very rapidly. In the application of the proposed algorithm to a five-reservoir hydropower system with 48 periods and a total of 230 decision variables, in early mating flights, the first feasible solution was identified and the results converged to a near optimal solution in later mating flights. In the case of the multi-reservoir problem, an efficient gradient-based nonlinear-programming solver (LINGO 8.0) failed to find a feasible solution and for the single hydropower reservoir design problem it performed much worse than the proposed algorithm.     

Error bounds in the averaging of hybrid systems

The authors analyze the error introduced by the averaging of hybrid systems. These systems involve linear systems which can take a number of different realizations based on the state of an underlying finite state process. The averaging technique (based on a formula from Lie algebras known as the Backer-Campbell-Hausdorff (BCH) formula) provides a single system matrix as an approximation to the hybrid system. The two errors discussed are: (1) the error induced by the truncation of the BCH series expansion and (2) the error between the actual hybrid system and its average. A simple sufficient stability test is proposed to check the asymptotic behavior of this error. In addition, conditions are derived that allow the use of state feedback instead of averaging to arrive at a time-invariant system matrix     

Determination of Sensory Thresholds of Selected Calcium Salts and Formulation of Calcium-fortified Pocket-type Flat Bread

Pita bread loaves were prepared from flours fortified with calcium carbonate, calcium sulfate, and tricalcium dicitrate at 8 ascending levels to provide ranges of 800 to 2500, 700 to 1500, and 400 to 2000 mg of added Ca/100 g flour, respectively. The detection thresholds of calcium salts in pita bread were determined by the 3‐alter‐native forced choice (3‐AFC) test and construction of dose‐response curves. Detection thresholds determined by calculating geometric mean of individual best estimate thresholds, using criterion of 50%‐above‐chance and probit analysis of 3‐AFC data, were in the middle region of calcium concentrations. Analysis of dose‐response curves yielded values for thresholds outside the range of surveyed calcium concentrations. The detection threshold of CaSO₄ (2724 mg/100 g) in pita bread was significantly higher (P < 0.01) than those of calcium carbonate (1984 mg/100 g) and tricalcium dicitrate (2132 mg/100 g). Calcium‐fortified pita bread was similar (P < 0.01) to its regular counterpart when formulated to contain 1254.6, 1772.5, or 1155 mg/100 g of CaCO₃, CaSO₄, or tricalcium dicitrate, respectively. At the indicated levels of fortification, calcium‐fortified pita bread is expected to provide between 61% and 126.5% of the recommended daily intake for calcium for Middle Eastern populations.     

Dynamic properties of calcareous and siliceous sands under isotropic and anisotropic stress conditions

The strain-dependent dynamic properties of sand are generally described by their relative density and mean effective stress, while the contribution of other factors, like soil origin, mineralogy, grain morphology, and initial stress anisotropy, have not been fully recognized. This paper presents the results of an experimental study on the shear modulus and damping ratio of calcareous and siliceous sands of different origins and their identical grain size distribution and stress-density states. Resonant column and cyclic triaxial tests were conducted on reconstituted samples of these two sands obtained from coastal areas. The significance of the initial effective confining pressure and stress anisotropy on the dynamic properties of the sands is evaluated and compared. It is demonstrated that the small-strain shear modulus of the calcareous sand is more affected by an increase in mean effective confining pressure than the siliceous sand. However, the effect of the initial shear on the secant shear modulus of the sands is unique. Based on the test data, a rigorous correction factor is proposed to account for the influence of the initial stress anisotropy on the small-strain shear modulus of the sands. A comparison between the strain-dependent dynamic properties of the calcareous and siliceous sands reveals that the calcareous sand has a higher secant shear modulus, lower damping ratio, and higher linear and volumetric threshold strain. Since the stress-density states and grain size distribution of the two sands were identical in the experiments, the discrepancy in the dynamic properties can be attributed to other factors, including sand origin, grain angularity, mineralogy, and formation processes, which are not commonly taken into account in the current practice.     

Simple N‐Heterocyclic Carbenes as Ligands in Ullmann‐Type Ether and Thioether Formations

A simple N‐heterocyclic carbene (NHC) derived from 1‐methyl‐3‐ethylimidazolium tetrafluoroborate was found to be an efficient ligand for a range of copper‐catalyzed cross‐coupling reactions, leading to the formation of aromatic ethers and thioethers.

     

The mystery of clustering in macromolecular media

Clustering occurs in most polar media such as water-soluble macromolecules. The true origin of clustering has been elusive despite a great deal of research effort. This paper uses the simplest water-soluble polymer, poly(ethylene oxide), dissolved in deuterated water to investigate the cause of clustering. The small-angle neutron scattering technique is used to separate out solvation effects from clustering effects and back out the various interaction parameters. It is found that clustering is related to attractive inter-chain interactions between hydrophobic groups which create physical crosslinks thereby causing clustering.     

Repair of heat-damaged reinforced concrete slabs using fibrous composite materials

Sixteen under-reinforced high strength concrete one-way slabs were cast, heated at 600 °C for 2 h, repaired, and then tested under four-point loading to investigate the coupling effect of water recuring and repairing with advance composite materials on increasing the flexural capacity of heat-damaged slabs. The composites used included high strength fiber reinforced concrete layers; and carbon and glass fiber reinforced polymer (CFRP and GFRP) sheets. Upon heating then cooling, the reinforced concrete (RC) slabs experienced extensive map cracking, and upward cambering without spalling. Recuring the heat-damaged slabs for 28 days allowed recovering the original stiffness without achieving the original load carrying capacity. Other slabs, recured then repaired with steel fiber reinforced concrete (SFRC) layers, regained from 79% to 84% of the original load capacity with a corresponding increase in stiffness from 382% to 503%, whereas those recured then repaired with CFRP and GFRP sheets, regained up to 158% and 125% of the original load capacity with a corresponding increase in stiffness of up to 319% and 197%, respectively. Control, heat-damaged, and water recured slabs showed a typical flexural failure mode with very fine and well distributed hairline cracks, propagated from the repair layers to concrete compression zone. RC slabs repaired with SFRC layers failed in flexural through a single crack, propagated throughout the compression zone, whereas those repaired with CFRP and GFRP experience yielding failure of steel prior to the composites failure.