Prognostic significance of DNA cytometry in cutaneous malignant lymphomas.

The current classification of cutaneous malignant lymphomas (ML) into low-grade and high-grade lymphomas was found to be of limited reproducibility and permitted only a rough prediction about outcome. With this in mind, the relationship between nuclear DNA content and both prognosis and histologic grading according to the Kiel classification was evaluated on Feulgen-stained imprint specimens. In all, 49 cases of malignant non-Hodgkin's lymphoma, primary of the skin or with an involvement of the skin as one of the first symptoms, were studied using a computerized high-resolution image analysis system. The 2c deviation index (2cDI), which reflects the variation of the nuclear DNA values around the normal diploid peak, was found to be the best prognostically relevant criterion. Using the 2cDI, a significant discrimination (P less than 0.001 in the U test) between low-grade and high-grade ML was achieved. The prognostic benefit of the 2cDI was well documented by a significant inverse correlation between the 2cDI and the period of time until the patients progressed at least into one higher stage or died of lymphoma (r equals -0.63, P less than 0.05). In addition, the 2cDI enabled prognosis of the course of disease. In the group with low 2cDI values (2cDI, less than 0.5), no progression of the disease was observed after 1 year. In the groups presenting with a 2cDI between 0.5 and 1.0 and higher than 1.0, a progression was found in 57% and 64% of the cases studied, respectively. In conclusion, these measurements indicate that the determination of DNA distribution patterns in imprint specimens allows a precise and objective prognostic evaluation of cutaneous ML

The competitive NMDA antagonist CPP protects substantia nigra neurons from MPTP-induced degeneration in primates

Degeneration of nigrostriatal dopaminergic neurons is the primary histopathological feature of Parkinson's disease. The neurotoxin MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) induces a neurological syndrome in man and non-human primates very similar to idiopathic Parkinson's disease by selectively destroying dopaminergic nigrostriatal neurons. This gives rise to the hypothesis that Parkinson's disease may be caused by endogenous or environmental toxins. Endogenous excitatory amino acids (EAAs) such as L-glutamate could be involved in neurodegenerative disorders including Parkinson's disease. We report in this study that the competitive NMDA antagonist CPP (3-((+/-)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid) protects nigral tyrosine hydroxylase (TH) positive neurons from degeneration induced by systemic treatment with MPTP in common marmosets. This indicates that EAAs are involved in the pathophysiological cascade of MPTP-induced neuronal cell death and that EAA antagonists may offer a neuroprotective therapy for Parkinson's disease

Near- and Sub-Threshold Design for Ultra-Low-Power Embedded Systems

Ultra-low-power (ULP) software-programmable architectures are gradually replacing dedicated VLSI circuits in many applications, including health care and other critical areas. However, the cost for more flexibility is the less frugal use of energy. This cost can be partially recovered by aggressive supply voltage scaling, often deep into the sub-threshold regime, which, however, raises concerns on performance, standby leakage, and reliability. In this talk, we will discuss some of the issues and possible solutions to ULP computing and embedded systems desigm at scaled voltages. We will discuss architectural choices and circuit level aspects and illustrate them with examples including robust Sub-VT memories, ULP multi-core systems, and Sub-VT application specific processors

Pion photoproduction off the proton in a gauge-invariant chiral unitary framework

We investigate pion photoproduction off the proton in a manifestly gauge-invariant chiral unitary extension of chiral perturbation theory. In a first step, we consider meson-baryon scattering taking into account all next-to-leading order contact interactions. The resulting low-energy constants are determined by a fit to s-wave pion-nucleon scattering and the low-energy data for the reaction pi- p --> eta n. To assess the theoretical uncertainty, we perform two different fit strategies. Having determined the low-energy constants, we then analyse the data on the s-wave multipole amplitudes E0+ of pion and eta photoproduction. These are parameter-free predictions, as the two new low-energy constants are determined by the neutron and proton magnetic moments.Comment: 23 pages, 17 figure

Suspended microchannel resonators for biomolecular detection

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (leaves 115-124).Microfabricated transducers enable the label-free detection of biological molecules in nanoliter sized samples. Integrating microfluidic detection and sample-preparation can greatly leverage experimental efforts in systems biology and pharmaceutical research by increasing analysis throughput while dramatically reducing reagent cost. Microfabricated resonant mass sensors are among the most sensitive devices for chemical detection, but degradation of the sensitivity in liquid has so far hindered their successful application in biology. This thesis introduces a type of resonant transducer that overcomes this limitation by a new device design: Adsorption of molecules to the inside walls of a suspended microfluidic channel is detected by measuring the change in mechanical resonance frequency of the channel. In contrast to resonant mass sensors submersed in water, the sensitivity and frequency resolution of the suspended microchannel resonator is not degraded by the presence of the fluid. Our device differs from a vibrating tube densitometer in that the channel is very thin, and only molecules that bind to the walls can build up enough mass to be detected; this provides a path to specificity via molecular recognition by immobilized receptors.(cont.) Suspended silicon nitride channels have been fabricated through a sacrificial polysilicon process and bulk micromachining, and the packaging and microfluidic interfacing of the resonant sensors has been addressed. Device characterization at 30 mTorr ambient pressure reveals a quality factor of more than 10,000 for water filled resonators; this is two orders of magnitude higher than previously demonstrated Q-values of resonant mass sensors for biological measurements. Calculation of the noise and the sensitivity of suspended microchannel resonators indicate a physical limit for mass resolution of approximately 0.01 ng/cm2 (1 Hz bandwidth). A resolution of -0.1 ng/cm2 has been experimentally demonstrated in this work. This resolution constitutes a tenfold improvement over commercial quartz crystal microbalance based instruments. The ability to detect adsorbing biomolecules by resonance frequency has been validated through binding experiments with avidin and various biotinylated proteins.by Thomas P. Burg.Ph.D

Dynamic SCL Decoder with Path-Flipping for 5G Polar Codes

Since polar were ratified as part of the 5G standard, low-complexity polar decoders with close-to-optimum error-rate performance have received significant attention. Compared to successive cancellation (SC) decoding, both SC list and SC flip decoding can improve the error rate performance by increasing the number of considered candidate solutions. The combination of both strategies leads to SC list flip (SCLF) decoding, which can provide a tradeoff between error rate performance and area as well as energy. In this letter, we derive a new flip metric for the SCLF decoding process, based on which we propose the dynamic SCLF (D-SCLF) decoding algorithm. Moreover, we exploit the distributed CRC defined in the 5G standard to further optimize the D-SCLF decoding. Numerical results show that for the downlink control channel, our D-SCLF decoder with a list size of only four and only three additional attempts can achieve the performance of a regular list decoder with a list size of eight, leading to an overall memory and average complexity (energy) reduction.</p

Petrology and Mineral Chemistry of Lower Crustal Intrusions: the Chilas Complex, Kohistan (NW Pakistan)

Mineral major and trace element data are presented for the main rock units of the Chilas Complex, a series of lower crustal intrusions emplaced during initial rifting within the Mesozoic Kohistan (paleo)-island arc (NW Pakistan). Detailed field observations and petrological analysis, together with geochemical data, indicate that the two principal units, ultramafic rocks and gabbronorite sequences, originate from a common parental magma, but evolved along different mineral fractionation trends. Phase petrology and mineral trace element data indicate that the fractionation sequence of the ultramafic rocks is dominated by the crystallization of olivine and clinopyroxene prior to plagioclase, whereas plagioclase precedes clinopyroxene in the gabbronorites. Clinopyroxene in the ultramafic rocks (with Mg-number [Mg/(Fetot + Mg] up to 0·95) displays increasing Al2O3 with decreasing Mg-number. The light rare earth element depleted trace element pattern (CeN/GdN ∼0·5-0·3) of primitive clinopyroxenes displays no Eu anomaly. In contrast, clinopyroxenes from the gabbronorites contain plagioclase inclusions, and the trace element pattern shows pronounced negative anomalies for Sr, Pb and Eu. Trace element modeling indicates that in situ crystallization may account for major and trace element variations in the gabbronorite sequence, whereas the olivine-dominated ultramafic rocks show covariations between olivine Mg-number and Ni and Mn contents, pointing to the importance of crystal fractionation during their formation. A modeled parental liquid for the Chilas Complex is explained in terms of mantle- and slab-derived components, where the latter component accounts for 99% of the highly incompatible elements and between 30 and 80% of the middle rare earth elements. The geochemical characteristics of this component are similar to those of a low percentage melt or supercritical liquid derived from subducted mafic crust. However, elevated Pb/Ce ratios are best explained by additional involvement of hydrous fluids. In accordance with the crystallization sequence, the subsolidus metamorphic reactions indicate pressures of 0·5-0·7 GPa. Our data support a model of combined flux and decompression melting in the back-ar