Shape optimization for tumor location

In non-invasive thermal diagnostics, accurate correlations between the thermal image at skin surface and interior human physiology are desired. In this work, an estimation methodology to determine unknown geometrical parameters of an embedded tumor is proposed. We define a functional that represents the mismatch between a measured experimental temperature profile, which may be obtained by infrared thermography on the skin surface, and the solution of an appropriate boundary problem. This functional is related to the geometrical parameters through the solution of the boundary problem, in such a way that finding the minimum of this functional form also means finding the unknown geometrical parameters of the embedded tumor. Sensitivity analysis techniques coupled with the adjoint method were considered to compute the shape derivative of the functional. Then, a nonmonotone spectral projected gradient method was implemented to solve the optimization problem of finding the optimal geometric parameters.     

Production of anti-erythrocyte antibodies by leukemic and nonleukemic B cells in chronic lymphocytic leukemia patients

We have assessed the specificity of antibodies from the leukemic B cells of five patients with both chronic lymphocytic leukemia and autoimmune hemolytic anemia (CLL-AHA). Leukemic cells from one patient displayed surface immunoglobulin with heavy and light chain isotypes identical to that of the patient's anti-red blood cell (RBC) antibodies, and the leukemic cells secreted antibodies in vitro with anti-RBC activity. However, in the remaining patients, the leukemic cells displayed surface immunoglobulin with light chain isotypes different from that of the patient's anti-RBC antibodies and secreted antibodies in vitro with no detectable anti-RBC activity. Thus, there are two distinct classes of CLL-AHA patients, differentiated by the presence or absence of an anti-RBC antibody-producing leukemic B cell clone. The apparent heterogeneity in the source of pathogenic anti-RBC antibodies may impact the treatment response of the two classes of CLL-AHA patients.     

Statistical discriminant analysis of arrhythmias using intracardialelectrograms

The problem of classifying ventricular arrhythmias from intracardial electrograms is considered. Standard statistical discrimination procedures are applied using a simple parametric model for the shape of the pulse near its peak. This approach makes simultaneous use of the model parameters, has well known statistical properties, and involves computations that can be carried out efficiently. Preliminary analyses of real data sets, using both linear and quadratic discrimination functions, yield promising results     

Nonblocking multirate distribution networks

Results for nonblocking distribution networks are generalized for the multirate environment in which different user connections share a switch's internal data paths for arbitrary fractions of the total capacity. Conditions under which network proposed by Y.P. Ofman (1965), C.D. Thompson (1978), and N. Pippenger (1973) lead to multirate distribution networks are derived. The results include both rearrangement and wide-sense nonblocking networks. The complexity of the rearrangement multirate network exceeds that of the corresponding space-division network by a log log factor, while the complexity of the wide-sense nonblocking network is within a factor of two of the corresponding space-division network     

A Catalytic and Positively Thermosensitive Molecularly Imprinted Polymer

A catalytic and positively thermosensitive molecularly imprinted polymer is reported. This unique imprinted polymer was composed of 4‐nitrophenyl phosphate‐imprinted networks that exhibited a thermosensitive interpolymer interaction between poly(2‐trifluoromethylacrylic acid) (PTFMA) and poly(1‐vinylimidazole) (PVI), which contains catalytically active sites. At a relatively low temperature (such as 20 °C), this imprinted polymer did not demonstrate significant catalytic activity for the hydrolysis of 4‐nitrophenyl acetate due to the interpolymer complexation between PVI and PTFMA, which blocked access to the active sites of PVI and caused shrinking of the polymer. Conversely, at higher temperatures (such as 40 °C), this polymer showed significant catalytic activity resulting from the dissociation of the interpolymer complexes between PVI and PTFMA, which facilitated access to the active sites of PVI and inflated the polymer. Unlike previously reported poly(N‐isopropylacrylamide)‐based molecularly imprinted polymers, which demonstrated decreased molecular recognition and catalytic activity with increased temperatures, i.e., negatively thermosensitive molecular recognition and catalysis abilities, this imprinted polymer exploits the unique interpolymer interaction between PVI and PTFMA, enabling the reversed thermal responsiveness.     

A Zipper‐Like On/Off‐Switchable Molecularly Imprinted Polymer

A zipper‐like on/off‐switchable molecularly imprinted polymer is reported. This unique imprinted polymer was composed of template‐imprinted polymeric networks that incorporate zipper‐like interactions between poly(acrylamide) (PAAm) and poly(2‐acrylamide‐2‐methyl propanesulfonic acid) (PAMPS). This polymer showed marginal recognition ability towards the imprint species under low temperature conditions, due to the interpolymer interaction between PAAm and PAMPS, which inhibited access to the imprinted networks. In contrast, at relatively high temperatures (such as 40 °C), the polymer demonstrated significant molecular recognition ability towards the imprint species resulting from the dissociation of the interpolymer complexes of PAAm and PAMPS, which enabled access to the imprint networks. Unlike previously reported PNIPAm‐based imprinted polymers, which demonstrate alterable molecular recognition simply because of the thermosensitive hydrophilicity/hydrophobicity of PNIPAm, this polymer employed a zipper‐like supramolecular architecture between PAAm and PAMPS, thereby enabling switchable molecular recognition.     

High-power high-efficiency quasi-CW Sb-based mid-IR lasers using1.9-μm laser diode pumping

Power efficiency is a critical issue for mid-infrared (mid-IR) semiconductor lasers. Previously, the highest power and efficiency 4-μm laser was pumped with 0.98-μm laser diode. This letter used 1.9-μm diode pumping for better quantum defect ratio and heat flow geometry. A 3.7-μm InAsSb-AlAsSb laser yielded a pump-power-limited 1.25-W single-ended output in 1-ms-long pulse with 6.5% net optical-to-optical efficiency, in contrast with a 0.67-W thermally limited output and 2.7% efficiency with 0.98-μm diode pumping, at 70 K. The results are believed to represent the highest quasi-continuous-wave power from a single device, highest efficiency, and, scaled to the emitting aperture, highest power density for any 3-4-μm semiconductor laser for 1-ms pulse and ⩾70 K     

GaInAsSb-AlGaAsSb tapered lasers emitting at 2.05 μm with 0.6-Wdiffraction-limited power

Tapered lasers fabricated from a GaInAsSb-AlGaAsSb single-quantum-well structure are reported. The laser structure, grown by molecular beam epitaxy, has broad-stripe pulsed threshold current densities as low as 50 A/cm² at room temperature. Tapered lasers have exhibited diffraction-limited continuous-wave output power up to 600 mW