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Despite the success of responsive neurostimulation (RNS) for epilepsy, clinical outcomes vary significantly and are hard to predict. The ability to forecast clinical response to RNS therapy before device implantation would improve patient selection for RNS surgery and could prevent a costly and ineffective intervention. Determining and validating biomarkers predictive of RNS response is difficult, however, due to the heterogeneity of the RNS patient population and clinical procedures; large, multi-center datasets are needed to quantify patient variability and to account for stereotypy in the treatment paradigm of any one center. Here we use a distributed, cloud-based pipeline to analyze a federated dataset of intracranial EEG recordings, collected prior to RNS surgery, from a retrospective cohort of 30 patients across three major epilepsy centers. Based on recent work modelling the controllability of distributed brain networks, we hypothesize that broader brain network connectivity, beyond the seizure onset zone, can predict RNS response. We demonstrate how intracranial EEG recordings can be leveraged through network analysis to uncover biomarkers that predict response to RNS therapy. Our findings suggest that peri-ictal changes in synchronizability, a global network metric shown to accurately predict outcome from resective epilepsy surgery, can distinguish between good and poor RNS responders under the current RNS therapy guidelines (area under the receiver operating characteristic curve of 0.75). Furthermore, this study also provides a proof-of-concept roadmap for multicenter collaboration where practical considerations impede sharing datasets fully across centers.

In this paper, we have explored Parylene-C (PC) as a sensing material for its unique signature and selectivity for explosive sensing. We have used a bi-layer deposition process to fabricate bottom-gate-top-contact organic field effect transistor (OFET) structures. Opening of dangling bonds on subjecting PC to plasma oxidation (POPC) renders these molecules to be employed as a receptor material in sensing vapors of both explosives and non-explosives, such as Trinitrotoulene (TNT), 1,3,5 trinitro-1,3,5-triazacyclohexane(RDX), PETN, Dinitrobenzene (DNB), Nitrobenzene (NB), Benzoquinone (BQ), and Benzophenone (BP). The change in: 1) the vibrational modes of the molecule by infrared spectroscopy; 2) surface potential of POPC by Kelvin probe force microscopy (KPFM); and 3) electrical characterization by I-V measurements of PC-based OFET on exposing to vapors have been systematically studied. Different signatures for all the analytes have been observed while exact and perfect selectivity for TNT, RDX were found from I-V studies and for PETN by KPFM studies. Thus, the OFET device-based chemical sensors demonstrated here with improved sensitivity and excellent selectivity, stand as promising candidates for explosives detection.

In this paper, we propose a novel technique of realizing discrete-time (D-T) signal amplification using Nano-Electro-Mechanical systems (NEMS). The amplifier uses mechanical switches instead of traditional solid-state devices and acts as an inherent sample and hold amplifier. The proposed NEMS D-T amplifier operates on a wide dynamic range of signals without consuming the dc power. Moreover, the proposed amplifier does not suffer from the leakage current and the nonlinearity associated with the sampling ohmic switch. As a proof of concept, the proposed NEMS D-T amplifier is demonstrated in circuit simulations using the calibrated verilog-A models of the NEMS device. The simulated amplifier achieves a gain of similar to 5, handles the maximum differential input signal of 0.65 V, and consumes only 0.6 mu W of power for a sampling frequency of 100 kHz. The nonidealities present in the proposed amplifier are highlighted and possible ways to overcome them are discussed. Finally, the design considerations required for the NEMS D-T amplifier are described.

This paper presents a new integration scheme to fabricate a Si/Si0.55Ge0.45 heterojunction line tunnel field effect transistor (TFET). The device shows an increase in tunneling current with gate length. The 1-mu m gate length device shows ON current in excess of 20 mu A/mu m at V-GS = V-DS = 1.2 V. Low-temperature measurements, performed to suppress trap-assisted tunneling (TAT), reveal the point subthreshold swing as low as 22 mV/dec at 78 K. Field-induced quantum confinement effects are found to increase the tunneling onset voltage by similar to 0.35 V. Variation of the tunneling onset voltage measured experimentally is correlated to variation in the pocket thickness and its doping concentration. Small geometry devices were found to be more susceptible to microvariations in the pocket thickness and doping concentration.

Local piezoelectric properties of ZnO nanoparticles (NPs) embedded in a photo-epoxy polymer are investigated by piezoresponse force microscopy (PFM). Integrating ZnO NPs into a photosensitive SU-8 polymer matrix not only retains the highly desired piezoelectric properties of the ZnO, but also preserves photosensitivity and optical transparency of the SU-8 polymer. These results have strong implications for simple photolithography based low-cost fabrication of piezoelectric microelectromechanicalsystems (MEMS) and nano-electromechanicalsystems (NEMS) in both sensing and energy harvesting applications. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Organic complementary inverters and ring oscillators are fabricated using a unique combination of inkjet printing and evaporation of organic semiconductors. p-Type poly (3, 3'''-didodecylquaterthiophene) (PQT) is inkjet printed, after which n-type copper hexadecafluorophthalocyanine (F(16)CuPc) is evaporated and patterned by shadow masking. A solution-processable bilayer gate dielectric with superior gate leakage characteristics and a simplified process stack is implemented. The inverters show a high noise margin, good gain characteristics, and a switching point close to V(dd)/2. A five-stage ring oscillator is also demonstrated.

Recycling of metals and alloys is important for conservation of natural mineral resources, reduction in energy consumption and minimization of environmental pollution. Light scrap of reactive metals and alloys containing reactive elements is diffifult to recyle by conventional methods of melting. At the Defence Metallurgical Research Laboratory (DMRL), Hyderabad, electroslag melting technologies have been developed for recycling light scrap of valuable metals and alloys such as superalloys and oxygen free high conductivity (OFHC) copper. Conventionally, electroslag melting processes use consumable electrodes. Because of the difficulty in compaction of scrap into a consumable electrode of satisfactory quality, non-consumable electrodes such as graphite and water-cooled copper have been designed. Electroslag remelting using water-cooled non-consumable electrode was used to melt scrap of a nickel base superalloy. Sound ingots with smooth surface finish and properties comparable to vacuum melted superalloys could be obtained from scrap using this process. OFHC copper scrap was melted by a modified electroslag crucible melting process using graphite crucible and graphite electrode. Process parameters including slag composition were optimised to produce copper ingots with oxygen less than 10 ppm and electrical conductivity approximate to 100% IACS. The same process was also utilised to produce copper-chromium (Cu-Cr) ingots starting from copper scrap and pure chromium metal. The alloy exhibited superior room temperature tensile properties and high temperature ductility. Alternatively, Cu-Cr could also be produced by in-situ reduction of chromium oxide by aluminium during electroslag crucible melting.

The electron velocity overshoot phenomenon in the inversion layer is experimentally investigated using a novel thin-film silicon-on-insulator (SOI) test structure with channel lengths down to 0.08 mu m, The uniformity of the carrier density and tangential field is realized by employing a lateral asymmetric channel (LAC) profile. The electron drift velocity observed in this work is 9.5 x 10(6) cm/s for a device with L(eff) = 0.08 mu m at 300 K. The upward trend in electron velocity can be clearly noticed for decreasing channel lengths.

The electroslag crucible melting process (ESCM), developed on the well established principles of electroslag refining was used to cast age hardening Cu-0.5%Cr alloys using copper scrap. The alloys exhibited superior room temperature tensile strength and ductility compared with conventional wrought material. An important aspect of the ESCM process is that there is considerable chemical refinement of the alloy with respect to both oxygen and sulphur due to reactions inherent in the process. This results in improved hot ductility (to the extent of similar to 45%) of the ESCM alloy compared with the material produced by the vacuum melting process. (C) 1997 The Institute of Materials.

The electroslag crucible melting process, developed on the well established principles of electroslag refining, has been used to cast age hardening Cu-0.5Cr alloys using copper scrap. Initial trials have demonstrated the viability of electroslag crucible melting for producing cast alloys with low impurity content and superior tensile properties. The castings produced by electroslag crucible melting are of high quality in terms of surface finish and casting defects. The cast alloy could be successfully dt awn into wire of diameter 3 mm.

Electroslag remelting (ESR) has been used to process an ordered Fe-28 at.-%Al intermetallic alloy. A commercial calcium fluoride based slag was used in the process. Oxygen, sulphur, and non-metallic inclusion levels were significantly reduced during ESR. The ingots exhibited a defect and segregation free structure with good surface finish. The mechanical properties of the ESR material, in the as cast condition, compared well with those reported for high purity wrought alloy of similar composition. The improved structure resulted in isotropic properties in the ESR processed material.

A case of human infection with Physaloptera causing an abscess in the neck of a patient in Hyderabad is recorded. The structure of one of the worms recovered, a female, is described and compared with that of other species recorded from mammals in India, but in the absence of the male it is not possible to determine the species.

Nitrogen fixation by Spirillum sp. obtained from the roots of rice plants grown at different levels of combined nitrogen was studied. The roots of rice plants exposed to low levels of combined nitrogen (20--40 kg N/ha) harboured Spirillum sp. possessing higher nitrogen-fixing efficiency as compared to the cultures from plants receiving 60--100 kg N/ha. Moreover, the nitrogen-fixing efficiency of these Spirillum spp. varied with age of the plant, irrespective of the dosage of combined nitrogen.

With the change in methods over time it seems appropriate to provide another case study of the precision of Ratio Correlation and to compare its accuracy with some of the more complex techniques of estimation. Detailed descriptions of the various methods employed in this report are available in several papers. This test compares 1960 population estimates of the 83 Michigan counties for each of four methods with the 1960 Census totals. All of the methods examined here use symptomatic indicators to estimate population. (excerpt)