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This paper presents novel adaptive schemes and the pertinent analysis for estimation of the number of targets, their associated radar cross section (RCS) values and Doppler velocities in monostatic MIMO radar systems. These schemes are based on the fast block least mean squares (FBLMS) and fast block recursive least squares (FBRLS) algorithms considering both stationary as well as mobile targets and/or radar platform. For the stationary scenario, schemes are proposed for estimation of RCS coefficients, target number and their angle, range locations. In addition, a procedure is also developed to obtain the 2D-image of the MIMO radar scene in angle-range dimensions. Analysis is presented for the first and second order moments of the observation as well as estimation errors resulting from the proposed FBLMS, FBRLS techniques, along with their global convergence. Both the proposed schemes are shown to converge globally to the optimal Wiener filter, which is lacking in existing schemes. Further, a Bayesian information criterion based selection rule is employed to enhance the estimation and imaging performance of the proposed adaptive frameworks. Cramer-Rao bounds are derived to characterize the mean squared error of the estimated RCS coefficients for stationary scenarios and also for joint RCS, Doppler velocity estimation in mobile MIMO radar scenarios. The FBLMS and FBRLS schemes are shown to have significantly lower computational complexities in comparison to existing MIMO radar schemes. Simulation results demonstrate the improved performance of the proposed schemes and also validate the derived analytical expressions. [ABSTRACT FROM AUTHOR]

BSTRACT: This study determined antioxidant effects and sensory attributes of individual ingredients (black pepper, caraway, cardamom, chili powder, cinnamon, cloves, coriander, cumin, fennel, ginger, nutmeg, salt, star anise) of an Indian spice blend (garam masala) in cooked ground beef. Thiobarbituric acid (TBA) values were measured as an indicator of rancidity for cooked samples on 1-, 8-, or 15-d refrigerated storage. Cooked samples were evaluated by a trained panel ( n= 13) for the intensity of rancid odor/flavor, beef flavor, and spice flavor and correlated with TBA values of same day samples. We also investigated possible additive effects between spice antioxidants and iron binding (type II) antioxidants on lipid oxidation by measuring TBA values. All spices had antioxidant effects on cooked ground beef, compared to controls. Among spices, cloves were the most effective in controlling lipid oxidation, with TBA values of 0.75, after 15-d refrigerated storage. All spices at their recommended levels lowered rancid odor and flavor in cooked ground beef, compared to controls. As expected, most spices also imparted distinctive flavors to cooked ground beef. There was a positive correlation (0.77) between TBA values on 15-d refrigerated storage and rancid odor/flavor. Type II antioxidants (iron-binding phosphate compounds) were more effective than individual type I antioxidants (spices and butylated hydroxytoluene; BHT) for maintenance of low TBA values in cooked ground beef during storage. Additive effects were observed with rosemary + milk mineral or sodium tripolyphosphate (STP) compared to rosemary alone. [ABSTRACT FROM AUTHOR]

BSTRACT This study determined antioxidant and sensory characteristics of cinnamon, cloves, fennel, pepper, and star anise (Chinese 5-spice ingredients) in cooked ground beef. Total aerobic plate counts were also measured. Mean thiobarbituric acid (TBA) values were high (3.4 ppm) for control cooked ground beef samples. With 1% use level, all spice treatments had lower pooled mean TBA values than controls. At the lowest use level of 0.1% of meat weight, all spices except pepper had lower TBA values than controls. Treatments with 0.1% cloves had lower ( P < 0.05) TBA values than 0.1% levels of other individual spices. Star anise, fennel, pepper, and cinnamon samples at 0.5% use level had lower mean TBA values than controls, but not different from 1.0% levels, respectively. Thus, the lowest effective spice level for cloves was 0.1% and 0.5% for the other spices. There was a high correlation ( P < 0.01) between TBA values and panel scores for rancid odor and flavor (0.83 and 0.78, respectively). Spice flavor was inversely correlated ( P < 0.01) with rancid odor and flavor (-0.57 and -0.61, respectively). The 5-spice blends did not affect microbial load of cooked samples compared with controls. In conclusion, all spices and blends had a dual effect, reducing rancid odor/flavor and imparting a distinctive flavor to cooked ground beef. [ABSTRACT FROM AUTHOR]

Human α-synuclein (α-Syn) is a natively unstructured protein whose aggregation into amyloid fibrils is associated with Parkinson disease (PD) pathogenesis. Mutations of α-Syn, E46K, A53T, and A30P, have been linked to the familial form of PD. In vitro aggregation studies suggest that increased propensity to form non-fibrillar oligomers is the shared property of these familial PD-associated mutants. However, the structural basis of the altered aggregation propensities of these PD-associated mutants is not yet clear. To understand this, we studied the site-specific structural dynamics of wild type (WT) α-Syn and its three PD mutants (A53T, E46K, and A30P). Tryptophan (Trp) was substituted at the N terminus, central hydrophobic region, and C terminus of all α-Syns. Using various biophysical techniques including time-resolved fluorescence studies, we show that irrespective of similar secondary structure and early oligomerization propensities, familial PD-associated mutations alter the site-specific microenvironment, solvent exposure, and conformational flexibility of the protein. Our results further show that the common structural feature of the three PD-associated mutants is more compact and rigid sites at their N and C termini compared with WT α-Syn that may facilitate the formation of a partially folded intermediate that eventually leads to their increased oligomerization propensities. [ABSTRACT FROM AUTHOR]

α-Synuclein (α-Syn) oligomerization and amyloid formation are associated with Parkinson's disease (PD) pathogenesis. Studying familial α-Syn mutants associated with early onset PD has therapeutic importance. Here we report the aggregation kinetics and other biophysical properties of a newly discovered PD associated Finnish mutation (A53E). Our in vitro study demonstrated that A53E attenuated α-Syn aggregation and amyloid formation without altering the major secondary structure and initial oligomerization tendency. Further, A53E showed reduced membrane binding affinity compared to A53T and WT. The present study would help to delineate the role of A53E mutation in early onset PD pathogenesis. [ABSTRACT FROM AUTHOR]