Some reactions of thiohydrazides and related compounds

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Semiconductor optical amplifiers in avionics

RSOAs have been demonstrated to operate within a WDM PON architectures over a >;60nm wavelength range with large path loss capabilities. Two RSOAs enable contiguous operation over the S, C and L bands; results indicate clearly that WDM architectures suitable for avionics with a PLC of >;25dB are possible with only two devices. Performance at extended temperature ranges will be reported later in detai

Intramedullary Nailing of Periarticular Fractures

Plate fixation has historically been the preferred surgical treatment method for periarticular fractures of the lower extremity. This trend has stemmed from difficulties with fracture reduction and concerns of inadequate fixation with intramedullary implants. However, the body of literature on management of periarticular fractures of the lower extremities has expanded in recent years, indicating that intramedullary nailing of distal femur, proximal tibia, and distal tibia fractures may be the preferred method of treatment in some cases. Intramedullary nailing reliably leads to excellent outcomes when performed for appropriate indications and when potential difficulties are recognized and addressed

Symmetry adapted Assur decompositions

Assur graphs are a tool originally developed by mechanical engineers to decompose mechanisms for simpler analysis and synthesis. Recent work has connected these graphs to strongly directed graphs, and decompositions of the pinned rigidity matrix. Many mechanisms have initial configurations which are symmetric, and other recent work has exploited the orbit matrix as a symmetry adapted form of the rigidity matrix. This paper explores how the decomposition and analysis of symmetric frameworks and their symmetric motions can be supported by the new symmetry adapted tools.Comment: 40 pages, 22 figure

Rigidity of frameworks on expanding spheres

A rigidity theory is developed for bar-joint frameworks in $\mathbb{R}^{d+1}$ whose vertices are constrained to lie on concentric $d$-spheres with independently variable radii. In particular, combinatorial characterisations are established for the rigidity of generic frameworks for $d=1$ with an arbitrary number of independently variable radii, and for $d=2$ with at most two variable radii. This includes a characterisation of the rigidity or flexibility of uniformly expanding spherical frameworks in $\mathbb{R}^{3}$. Due to the equivalence of the generic rigidity between Euclidean space and spherical space, these results interpolate between rigidity in 1D and 2D and to some extent between rigidity in 2D and 3D. Symmetry-adapted counts for the detection of symmetry-induced continuous flexibility in frameworks on spheres with variable radii are also provided.Comment: 22 pages, 2 figures, updated reference

Nitroblue tetrazolium: its use in the diagnosis of infection and in the study of leukocytes, lipoproteins and liposomes

A rapid, objective indicator of pyogemc infection would be of great value in the practice of clinical medicine. On the basis of earlier studies it was claimed that the nitroblue tetrazolium ( NBT) test might fulfill such a role. In view of the potential value of this test, it was reassessed m order to determine its diagnostic accuracy and clinical value. The results obtained in this study did not conform with those previously published. Elevated NBT scores were not diagnostic of pyogenic infection, there was a wide overlap of the results of tests performed on patients with pyogenic disease, patients with other diseases and normal subjects. In addition, there was a significant observer error in the interpretation of the slide preparations. The extent of this error was reduced with experience, but was still considerable in the hands of experienced observers. In the NBT test, the dye enters neutrophils by phagocytosis of NBT in particulate form, complexed to heparin and/or '·fibrinogen. The proportion of neutrophils which phagocytose these complexes seems to be related to the severity of illness of the patient. As serum from these patients is capable of enhancing phagocytosis of complexed dye by normal cells, a humeral factor could be responsible for the increased phagocytosis of complexed NBT indicated by a positive test. , Of the compounds tested, man m vitro model system designed to simulate the NBT test, 3 a,l_acid glycoprotein, immunoglobulins and endotoxin, in concentrations that occur in vivo, enhanced NBT reduction. Any one of these compounds, singly or in combination, could be responsible for positive NBT tests