Philadelphia positive acute lymphoblastic leukemia 16 years after the apparent cure of acute lymphoblastic leukemia. New leukemia or late relapse?

A Philadelphia-positive ALL in an adult occurring 21 years after the initial diagnosis is reported here. This case raises the question as to whether or not this event is a relapse or a new leukemia. A possible role of interferon-alpha previously administered to the patient for a chronic viral hepatitis is discussed too.     

Methane biodegradation in a two‐phase partition internal loop airlift reactor with gas recirculation

BACKGROUND: The potential of organic liquid solvents and solid polymers to enhance CH₄ mass transfer was studied in a two‐phase partition internal loop airlift reactor operated with gas recirculation under biotic and abiotic conditions. A preliminary screening of the most common liquid solvents (silicone oil 20 cSt, silicone oil 200 cSt and 2,2,4,4,6,8,8‐heptametilnonane) and solid polymers (Kraton® G6157, Desmopan® DP9370A and Elvax® 880) resulted in the selection of silicone oil 200 cSt (S200) and Desmopan DP9370A (D9370) for further investigation based on their high affinity for CH₄, biocompatibility and nonbiodegradability. RESULTS: Under abiotic conditions, the increase in gas recirculation from 0 to 1 vvm in the absence of a transfer vector increased the overall mass transfer coefficient for oxygen (k_La) by 195%. The presence of S200 and D9370 at 10% (v/v) under operation at 1 vvm of gas recirculation rate mediated an increase in k_La of 100% and 136%, respectively. Likewise, the increase in gas recirculation from 0 to 1 vvm in the absence of a transfer vector and in the presence of S200 during the continuous biodegradation of methane at 3% (v/v) and 7.3 min empty bed residence time resulted in increases in CH₄ removal and CO₂ production rates of 47% and 36%, respectively. Nevertheless, no significant enhancement in CH₄ removal due to the presence of 10% of Desmopan or silicone oil was recorded under operation at 1 vvm. CONCLUSIONS: These results suggest that microbial activity rather than mass transport could be the limiting step in biological CH₄ abatement in this system, contrary to that observed in previous studies with stirred tank reactors, where the organic phase addition increased methane biodegradation. Copyright © 2010 Society of Chemical Industry     

Model-based techniques for the testing and diagnosis of micro-manufacturing devices and machines

One of the main difficulties in developing a testing-and-diagnosis system for micro-manufacturing devices and machines is that the measurement process can require a high number of sensors, and is often too complex, in order to avoid external disturbances under normal working conditions, and the sensors are also not easy to allocate due to the minimal space available. At the present time, modern techniques of control-system engineering can be applied to propose a model-based testing and diagnosis methodology that reduces the number of the required sensors, due to a priori knowledge of the system expressed in terms of mathematical relationships between the physical variables. The Mechatronic Variable Estimation Library was created as a tool to estimate the value of “unknown” variables and parameters of the micro-device or machine using only a few sensors, reducing in this way the cost of the testing system and making the product of interest for industrial applications.     

Vanadium Oxide Thin Films Alloyed with Ti, Zr, Nb, and Mo for Uncooled Infrared Imaging Applications

Microbolometer-grade vanadium oxide (VO _x ) thin films with 1.3 < x < 2.0 were prepared by pulsed direct-current (DC) sputtering using substrate bias in a controlled oxygen and argon environment. These films were systematically alloyed with Ti, Nb, Mo, and Zr using a second gun and radiofrequency (RF) reactive co-sputtering to probe the effects of the transition metals on the film charge transport characteristics. The results reveal that the temperature coefficient of resistance (TCR) and resistivity are unexpectedly similar for alloyed and unalloyed films up to alloy compositions in the ～20 at.% range. Analysis of the film structures for the case of the 17% Nb-alloyed film by glancing-angle x-ray diffraction and transmission electron microscopy shows that the microstructure remains even with the addition of high concentrations of alloy metal, demonstrating the robust character of the VO _x films to maintain favorable electrical transport properties for bolometer applications. Postdeposition thermal annealing of the alloyed VO _x films further reveals improvement of electrical properties compared with unalloyed films, indicating a direction for further improvements in the materials.     

A MODEL FOR SHORT FATIGUE CRACK PROPAGATION WITH AN INTERPRETATION OF THE SHORT-LONG CRACK TRANSITION

The behaviour of short cracks approaching growth barriers (e.g. grain boundaries) is considered. The crack model of Bilby, Cottrell and Swinden is applied to simulate the blocking of the plastic zone at the grain boundary and to obtain the stress concentration ahead of the crack as it approaches the barrier. The idea of the Hall-Petch type relationship that the transmission of slip across grain boundaries needs the previous achievement of a critical stress has been used. By making the crack growth rate proportional to the plastic displacement at the root of the crack the deceleration behaviour of short cracks and the existence of non-propagating cracks may be explained. The fatigue limit is related to the stress below which a crack growing in a single grain is unable to promote slip in the neighbouring grain. The different behaviour in the so-called long crack period has been rationalized in terms of the plastic zone exceeding the grain size. For this case, and in the grain completely included within the plastic zone, the Hall-Petch analysis must be applied. Hence the maximum back-stress sustained by this grain cannot exceed the yield stress. After this point the Bilby et al. model is used with uy as a friction stress (i.e. the Dugdale model). Finally use is made of Fracture Mechanics to correlate the results in the long crack phase.     

In defense of Piaget's theory: A reply to 10 common criticisms.

The developmental theory of Jean Piaget has been criticized on the grounds that it is conceptually limited, empirically false, or philosophically and epistemologically untenable. This study attempts to rebut these criticisms by showing that most of them (a) derive from widespread misinterpretations of the work of Piaget; (b) fail to appreciate the 2 central issues of his thinking—how new forms of thinking emerge during ontogenesis and how they become psychologically necessary; (c) incorrectly assume that many controversies concerning his theory can be settled empirically or methodologically before they are clarified conceptually; (d) ignore various modifications of Piagetian theory, particularly those advanced after 1970; and (e) forget the dialectical, constructivist, and developmental nature of Piaget's unique approach to human development. Although the authors do not claim there is a "true" Piaget to be discovered, or that the problems with his theory vanish when it is better understood, they do claim that important aspects of Piaget's work have not been assimilated by developmental psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Multidimensional scaling as a method to correlate sensory and instrumental data of orange juice aromas

Changes of orange juice aromas due to storage time and temperature were studied through sensory detection of differences between samples, and by gas chromatographic analysis of 38 volatile constituents. Multidimensional scaling was applied to sensory and instrumental data prior to correlation analysis. Absolute concentrations of volatile constituents were not correlated with sensory data but higher correlations were observed with normalised analytical data. Thus, correlation coefficients were respectively 0.47 and 0.74 when considering (i) relative concentrations of all volatiles, by expressing the concentration of each constituent in a sample as a proportion of the maximum observed concentration of this constituent; and (ii) relative concentrations of only those constituents showing significant (95% level) changes due to storage length or temperature.     

Large-signal characteristics of InP-based heterojunction bipolartransistors and optoelectronic cascode transimpedance amplifiers

A large-signal model for InP/InGaAs-based single HBTs incorporating soft-breakdown effects to the LIBRA Gummel-Poon (GP) model is developed and its validity is established from DC to microwave frequencies and over a wide range of input excitation levels. The large-signal characteristics of a cascode InP-based transimpedance optoelectronic preamplifier employing such devices are studied. Gain compression for the preamplifier was found to take place at an input power level of -20 dBm. Input power excitation varying from -65 to -5 dBm results in a degradation of the amplifier transimpedance gain of the order of 3 dBn. Experimental and theoretical characteristics are presented for the InP-based HBTs and transimpedance amplifier. Self-biasing effects are suggested as possible origin of the transimpedance variations with input power