In vitro studies on antioxidants and free radical scavenging activities in the extracts of Loranthus longiflorus desr. bark samples obtained from two host trees

Antioxidant compounds and their free radical scavenging (FRS) activities in various solvent extracts of Loranthus longiflorus bark samples collected from Casuarina equisetifolia and Ficus religiosa host trees were assessed. The results obtained confirm the presence of total flavonoids, total phenols and total tannins in all extracts at different proportions. Among the extracts tested, ethyl acetate extract shows maximum total phenols (301.25mg/g and 307.27mg/g) and total tannins (11.46mg/g and 204.83mg/g),while chloroform extract favours more amount  of flavonoids (18.92mg/g and 26.13mg/g) in Loranthus bark samples collected from the host Casuarina and Ficus, respectively. Among the extracts of Loranthus bark samples, collected from Casuarina and Ficus, ethanol extract shows maximum scavenging activity on DPPH (4681.8% and 4890.6% at 1500µg), on Hydroxyl (49.37% and 55.58% at 250 µg), ethyl acetate (49.79%) and water extract (48.28%) on Nitric oxide (at 250µg) and ethanol (33.71%) chloroform (34.85%) on Superoxide (at 250 µg), respectively, as compared to other extracts. All the FRS activities, tested, were concentration dependent. The inhibitory concentration (IC50) was determined in ethanol extracts as 5.70µg/ml and 5.32µg/ml for DPPH-FRS activity; as 34.34µg/ml and 38.35 µg/ml for HO-FRS activity, as 108.93µg/ml and 104.32µg/ml for SO-FRS activity and ethyl acetate extract as 188.5µg/ml and 116.1µg/ml for NO-FRS activity of Loranthus bark samples collected from Casuarina and Ficus, respectively, than other extracts, tested. The ferric reducing antioxidant power of Loranthus bark samples, from Casuarina and Ficus hosts, was maximum in ethanol extract (4053.53 and 4199.03mMol Fe (II)/mg extract, respectively) than other extracts tested. These results indicate that the host trees, on which the hemiparasite infested, influence the variations in antioxidant constituents and free radical scavenging activities of L. longiflorus bark extracts

A 0.6V 2.9µW mixed-signal front-end for ECG monitoring

This paper presents a mixed-signal ECG front-end that uses aggressive voltage scaling to maximize power-efficiency and facilitate integration with low-voltage DSPs. 50/60Hz interference is canceled using mixed-signal feedback, enabling ultra-low-voltage operation by reducing dynamic range requirements. Analog circuits are optimized for ultra-low-voltage, and a SAR ADC with a dual-DAC architecture eliminates the need for a power-hungry ADC buffer. Oversampling and ΔΣ-modulation leveraging near-V[subscript T] digital processing are used to achieve ultra-low-power operation without sacrificing noise performance and dynamic range. The fully-integrated front-end is implemented in a 0.18μm CMOS process and consumes 2.9μW from 0.6V.Texas Instruments IncorporatedNatural Sciences and Engineering Research Council of Canada (Fellowship

A 0.6V, 8mW 3D Vision Processor for a Navigation Device for the Visually Impaired

This paper presents an energy-efficient computer vision processor for a navigation device for the visually impaired. Utilizing a shared parallel datapath, out-of-order processing and co-optimization with hardware-oriented algorithms, the processor consumes 8mW at 0.6V while processing 30 fps input data stream in real time. The test chip fabricated in 40nm is demonstrated as a core part of a navigation device based on a ToF camera, which successfully detects safe areas and obstacles.Texas Instruments Incorporate

Computer-Assisted Prototyping of Advanced Microsystems

Contains reports on five research projects.Defense Advanced Research Projects Agency Contract DABT 63-95-C-0088Stanford Universit

Energy extraction from the biologic battery in the inner ear

Endocochlear potential (EP) is a battery-like electrochemical gradient found in and actively maintained by the inner ear [superscript 1, 2]. Here we demonstrate that the mammalian EP can be used as a power source for electronic devices. We achieved this by designing an anatomically sized, ultra-low quiescent-power energy harvester chip integrated with a wireless sensor capable of monitoring the EP itself. Although other forms of in vivo energy harvesting have been described in lower organisms [superscript 3, 4, 5], and thermoelectric [superscript 6], piezoelectric [superscript 7] and biofuel [superscript 8, 9] devices are promising for mammalian applications, there have been few, if any, in vivo demonstrations in the vicinity of the ear, eye and brain. In this work, the chip extracted a minimum of 1.12 nW from the EP of a guinea pig for up to 5 h, enabling a 2.4 GHz radio to transmit measurement of the EP every 40–360 s. With future optimization of electrode design, we envision using the biologic battery in the inner ear to power chemical and molecular sensors, or drug-delivery actuators for diagnosis and therapy of hearing loss and other disorders.Focus Center Research Program. Focus Center for Circuit & System Solutions. Semiconductor Research Corporation. Interconnect Focus CenterNational Institutes of Health (U.S.) (Grant K08 DC010419)National Institutes of Health (U.S.) (Grant T32 DC00038)Bertarelli Foundatio

Custom Integrated Circuits

Contains table of contents for Part III, table of contents for Section 1 and reports on eleven research projects.IBM CorporationMIT School of EngineeringNational Science Foundation Grant MIP 94-23221Defense Advanced Research Projects Agency/U.S. Army Intelligence Center Contract DABT63-94-C-0053Mitsubishi CorporationNational Science Foundation Young Investigator Award Fellowship MIP 92-58376Joint Industry Program on Offshore Structure AnalysisAnalog DevicesDefense Advanced Research Projects AgencyCadence Design SystemsMAFET ConsortiumConsortium for Superconducting ElectronicsNational Defense Science and Engineering Graduate FellowshipDigital Equipment CorporationMIT Lincoln LaboratorySemiconductor Research CorporationMultiuniversity Research IntiativeNational Science Foundatio