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We implemented neuromorphic artificial touch and emulated the firing behavior of mechanoreceptors by injecting the raw outputs of a biomimetic tactile sensor into an Izhikevich neuronal model. Naturalistic textures were evaluated with a passive touch protocol. The resulting neuromorphic spike trains were able to classify ten naturalistic textures ranging from textiles to glass to BioSkin, with accuracy as high as 97%. Remarkably, rather than on firing rate features calculated over the stimulation window, the highest achieved decoding performance was based on the precise spike timing of the neuromorphic output as captured by Victor Purpura distance. We also systematically varied the sliding velocity and the contact force to investigate the role of sensing conditions in categorizing the stimuli via the artificial sensory system. We found that the decoding performance based on the timing of neuromorphic spike events was robust for a broad range of sensing conditions. Being able to categorize naturalistic textures in different sensing conditions, these neurorobotic results pave the way to the use of neuromorphic tactile sensors in future real-life neuroprosthetic applications.We provide supplemental data to a vibrator array tactile display, as well as additional data for application of the edge stimulation (ES) method proposed in our previous study. By vibrating two surfaces in different phases and touching their boundary, a strong continuous line sensation, not on the vibrators themselves, but along the boundary, is obtained. This vibrotactile edge is suitable for presenting virtual lines, areas, and shapes on a rigid flat surface. We investigated the fundamental performance of the ES method through psychophysical experiments. The effects on the vibrotactile detection thresholds were investigated for three mechanical parameters, i.e., the vibratory frequency, the phase difference between the vibrations, and the gap distance between adjoining vibratory surfaces. Two-line discrimination thresholds for lines presented by the ES method were also determined. We found that the detection thresholds under the ES method was lower than 10 um even at the low frequencies (lower than 50 Hz), which is significantly lower than that under simply touching to a single vibratory surface. A comparison of the perceived widths revealed that the ES method provides a more localized tactile image than a single-pin vibrator or a flat-top vibrator. A 3 X 3 vibrator array display was developed using the ES method based on the properties obtained from the experiments. Seven categories of display patterns were presented with the ES array display and the participants' responses matched at 95 percent.Electrovibration is a type of surface haptics that can modulate lateral forces acting between a fingertip and a touch surface. Electrovibration is fast, consumes little power, and does not involve the use of any mechanical actuators. However, it suffers from problems such as nonuniform perceived intensity due to varying environmental impedances, as well as possible electric shock, which have to be solved for commercialization. In this paper, a current feedback method is proposed to provide uniform intensity of electrovibration, regardless of the varying environmental impedances. The proposed method can also prevent electric shock. To show the effectiveness of the proposed method, a hardware prototype was developed and a user study was conducted. The user study result shows that the proposed current control method can provide significantly more uniform perceived intensity of electrovibration as compared with the conventional voltage control method.This study investigated the environmental quality of the Bizerte Lagoon (Tunisia) through an integrated approach that combined environmental, biogeochemical, and living benthic foraminiferal analyses. Specifically, we analyzed the physicochemical parameters of the water and sediment. The textural, mineralogical, and geochemical characteristics of the sediment, including total organic carbon, total nitrogen, simultaneously extracted metals (SEM), acid volatile sulfides (AVS), chlorophyll a, CaCO3, and changes in bacterial populations and carbon isotopes were measured. The SEM/AVS values indicated the presence of relatively high concentrations of toxic metals in only some areas. Foraminiferal assemblages were dominated by species such as A. parkinsoniana (20-91%), Bolivina striatula ( less then 40%), Hopkinsina atlantica ( less then 17%), and Bolivina ordinaria ( less then 15%) that cannot be considered typical of impacted coastal lagoons both in Mediterranean and northeast Atlantic regions. The results of this work suggest that Bizerte Lagoon is a unique setting. This lagoon is populated by typical marine species that invaded this ecosystem, attracted not only by the prevailing favorable environmental conditions but also by the abundance and quality of food. The results indicate that the metal pollution found in some areas have a negative impact on the assemblages of foraminifera. At present, however, this negative impact is not highly alarming.An efficient total synthesis of the potent V-ATPase inhibitor saliphenylhalamide (SaliPhe), a synthetic variant of the natural product salicylihalamide A (SaliA), has been accomplished aimed at facilitating the development of SaliPhe as an anticancer and antiviral agent. This new approach enabled facile access to derivatives for structure-activity relationship studies, leading to simplified analogs that maintain SaliPhe's biological properties. These studies will provide a solid foundation for the continued evaluation of SaliPhe and analogs as potential anticancer and antiviral agents.Previous work investigating tricyclic pyrrolopyrazines as kinase cores led to the discovery that 1-cyclohexyl-6H-pyrrolo[2,3-e][1,2,4]triazolo[4,3-a]pyrazine (12) had Jak inhibitory activity. Herein we describe our initial efforts to develop orally bioavailable analogs of 12 with improved selectivity of Jak1 over Jak2.Pentafluorosulfanyl-containing analogs of flufenamic acid have been synthesized in high yields. Computationally, pKa, LogP and LogD values have been determined. Initial bioactivity studies reveal effects as ion channel modulators and inhibitory activities on aldo-keto reductase 1C3 (AKR1C3) as well as COX-1 and COX-2.A new family of CaaX competitive inhibitors of human farnesyltransferase based on phenothiazine and carbazole skeleton bearing a l-cysteine, l-methionine, l-serine or l-valine moiety was designed, synthesized and biologically evaluated. Phenothiazine derivatives proved to be more active than carbazole-based compounds. Phenothiazine 1b with cysteine residue was the most promising inhibitor of human farnesyltransferase in the current study.We report the design, synthesis, biological activity and docking studies of series of novel pyrazolo[3,4-d]pyrimidinones as DPP-IV inhibitors in diabetes. Molecules were synthesized and evaluated for their DPP-IV inhibition activity. Compounds 5e, 5k, 5o and 6a were found to be potent inhibitors of DPP-IV enzyme. Amongst all the synthesized compounds, 6-methyl-5-(4-methylpyridin-2-yl)-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-one (5k) was found to be the most active based on in vitro DPP-IV studies and also exhibited promising in vivo blood glucose lowering activity in male Wistar rats.The sampling of the bacterial signal transduction is investigated for molecular communication (MC). Ulixertinib order It is assumed that the finite-duration amplitude modulated, i.e., pulse-amplitude modulated (PAM), concentration of a certain type of molecule is used for information transmission. The bacterial signaling pathway is modified to transduce the input molecules to the output signal, i.e., produce green fluorescent protein (GFP). The bacterial signal transduction is composed of a set of biochemical reactions which impose randomness on the response. Therefore, the input-output relation, the timing issues, and the noise effects for the bacteria response are characterized based on both analytical and experimental observations. Sampling schemes for the raw bacteria response are proposed based on the total response duration, the peak value, the ramp-up slope, and the ramp-down slope. Each sampling scheme is shown to be providing a one-to-one and monotonic function of the input. The sampling based on the ramp-up slope is shown to be statistically favorable for the detection of PAM molecular signals. Accordingly, the time interval selection and non-coherent sampling are studied for the efficient calculation of the ramp-up slope from the raw bacteria response. This work provides a basis for the sampling of the raw bacteria response and enables accurate detection of PAM molecular signals via bacterial response for MC and sensing applications.We review the field of synthetic biology from an analog circuits and analog computation perspective, focusing on circuits that have been built in living cells. This perspective is well suited to pictorially, symbolically, and quantitatively representing the nonlinear, dynamic, and stochastic (noisy) ordinary and partial differential equations that rigorously describe the molecular circuits of synthetic biology. This perspective enables us to construct a canonical analog circuit schematic that helps unify and review the operation of many fundamental circuits that have been built in synthetic biology at the DNA, RNA, protein, and small-molecule levels over nearly two decades. We review 17 circuits in the literature as particular examples of feedforward and feedback analog circuits that arise from special topological cases of the canonical analog circuit schematic. Digital circuit operation of these circuits represents a special case of saturated analog circuit behavior and is automatically incorporated as well. Many issues that have prevented synthetic biology from scaling are naturally represented in analog circuit schematics. Furthermore, the deep similarity between the Boltzmann thermodynamic equations that describe noisy electronic current flow in subthreshold transistors and noisy molecular flux in biochemical reactions has helped map analog circuit motifs in electronics to analog circuit motifs in cells and vice versa via a `cytomorphic' approach. Thus, a body of knowledge in analog electronic circuit design, analysis, simulation, and implementation may also be useful in the robust and efficient design of molecular circuits in synthetic biology, helping it to scale to more complex circuits in the future.Intracellular protein copy numbers show significant cell-to-cell variability within an isogenic population due to the random nature of biological reactions. Here we show how the variability in copy number can be controlled by perturbing gene expression. Depending on the genetic network and host, different perturbations can be applied to control variability. To understand more fully how noise propagates and behaves in biochemical networks we developed stochastic control analysis (SCA) which is a sensitivity-based analysis framework for the study of noise control. Here we apply SCA to synthetic gene expression systems encoded on plasmids that are transformed into Escherichia coli. We show that (1) dual control of transcription and translation efficiencies provides the most efficient way of noise-versus-mean control. (2) The expressed proteins follow the gamma distribution function as found in chromosomal proteins. (3) One of the major sources of noise, leading to the cell-to-cell variability in protein copy numbers, is related to bursty translation.

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