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Rate region analysis of multi-terminal neuronal nanoscale molecular communication channel
© 2017 IEEE. In this paper, we investigate the communication channel capacity among hippocampal pyramidal neurons. To this aim, we study the processes included in this communication and model them with realistic communication system components based on the existing reports in the physiology literature. We consider the communication between two neurons and reveal the effects of the existence of multiple terminals between these neurons on the achievable rate per spike. To this objective, we derive the power spectral density (PSD) of the signal in the output neuron and utilize it to calculate the rate region of the channel. Moreover, we evaluate the impacts of vesicle availability on the achievable rate by deriving the expected number of available vesicles in input neuron using a realistic vesicle release model. Simulation results show that number of available vesicles for release does not affect the achievable rate of neuro-spike communication with univesicular release model. However, in neurons that multiple vesicles can release from each synaptic terminal, achievable rate is significantly affected by depletion of vesicles. Moreover, we show that increasing the number of synaptic terminals between two neurons makes the synaptic connection stronger. Hence, it is an important factor in learning and memory, which occur in the hippocampal region of the brain based on the synaptic connectivity
Internet of Hybrid Energy Harvesting Things
© 2017 IEEE. Internet of Things (IoT) is a perfect candidate to realize efficient observation and management for Smart City concept. This requires deployment of large number of wireless devices. However, replenishing batteries of thousands, maybe millions of devices may be hard or even impossible. In order to solve this problem, Internet of Energy Harvesting Things (IoEHT) is proposed. Although the first studies on IoEHT focused on energy harvesting (EH) as an auxiliary power provisioning method, now completely battery-free and self-sufficient systems are envisioned. Taking advantage of diverse sources that the concept of Smart City offers helps us to fully appreciate the capacity of EH. In this way, we address the primary shortcomings of IoEHT; availability, unreliability, and insufficiency by the Internet of Hybrid EH Things (IoHEHT). In this paper, we survey the various EH opportunities, propose an hybrid EH system, and discuss energy and data management issues for battery-free operation. We mathematically prove advantages of hybrid EH compared to single source harvesting as well. We also point out to hardware requirements and present the open research directions for different network layers specific to IoHEHT for Smart City concept
In silico identification, characterization and expression analysis of miRNAs in Cannabis sativa L.
AbstractCannabis sativa L. is an annual herb and economically important as a source of fiber, oil, food and for its medicinal and intoxicating properties. MicroRNAs are a class of short (~21nt), non-coding regulatory RNAs that play a major role in post-transcriptional gene silencing. By in silico analysis of the publically available Transcript Sequence Assemblies (TSA) and Expressed Sequence Tags (ESTs) of C. sativa, a total of 18 conserved miRNAs belonging to 9 independent families were identified. To validate the predicted miRNAs, SYBR green based assay of qPCR was applied to detect the tissue-specific (young and mature leaf) expression of 6 putative miRNAs (csa-miR156, csa-miR159a, csa-miR171b, csa-miR172a, csa-miR5021a, csa-miR6034) in C. sativa. A total of 80 target genes were also recognized for the newly identified miRNAs, and subsequently assigned to three broad functional categories: biological processes, cellular components and molecular functions as defined for the Arabidopsis proteome. The potential target genes consist of transcription factors (33.75%), transporters (5%), kinase and other enzymes (20%) as well as signaling and other functional proteins (32.50%). The findings in this study on C. sativa miRNA precursors, mature miRNAs, and miRNA targets will be helpful for future research on miRNA-mediated gene regulation in this important plant species
Determination of Levels of Regulated and Emerging Trihalomethanes (THMs) Disinfection By-Products (DBPs) in a Community Drinking Water Supply
Ahmadu Bello University (ABU) drinking water treatment plant (ABUDWTP) uses calcium hypochlorite to
supply chlorine in disinfecting drinking water supply to the university community. Between 2008 and 2010, 252
water samples were taken in duplicates along the treatment and distribution systems of ABUDWTP with
ammonium chloride as de-chlorinating agent in accordance with United States Environmental Protection Agency
(USEPA) Method 551.1. This was aimed at determining the concentrations of trihalomethanes (THMs)
disinfection by-products (THM-DBPs) and the degree of wholesomeness of the drinking water supplied. The
THM concentrations in the samples were analysed using Agilent Gas Chromatograph after preliminary
extraction with methyl tert-butyl ether (MTBE). Samplesâ analyses identified six THMs - two additional to the
regulated four. These are Dichlorobromomethane and 1,2-Dibromomethane here classified as emerging THM
disinfection by-products (EmerTHM-DBPs). Measured total mean concentration of the regulated THMs
(TRegTHM-DBPs) at house level was 1.0601E-02±1.6625E-05 mg/L as against 9.9704E-02±6.4706E-05 mg/L
for total mean emerging THM-DBPs (TEmergTHM-DBPs). This TRegTHMs concentration indicates house
level water is within acceptable limits of international standards despite being above the national permissible
limit of 0.001 mg/L. Though not considered under exiting drinking water quality index TEmergTHM-DBPs
were found to account for over 90% of gross THM-DBPs (GTTHM-DBPs) at each sampling stage. These
TEmergTHM-DBPs could create health complications on consumers as they are either suspected carcinogens or
recognised to increase the risk of carcinogenicity and mutagenicity in humans. Both are irritants of several body
tissues and are implicated in several health abnormalities including reproductive and fertility disorders as well as
liver and kidney damage. In view of these likely supplementary health burdens, this paper advocates additional
stricter monitoring and control of these emerging THM-DBPs as they will most probably compound and increase
the frontline of health challenges from chlorine disinfected ABU drinking water supply to its consumer
Phenology, Morphology and Physiology Responses of Deficit Irrigated âKoroneikiâ Olive Trees as Affected by Environmental Conditions and Alternate Bearing
Climate change is affecting water resources in the Mediterranean region. In olive orchards, irrigation water use efficiency could be increased by accounting for treesâ alternate bearing behaviour and growth-stage sensitivity to drought. The main objective of this study is to examine olive tree phenology, morphology and physiology in âonâ and âoffâ productive years for the improvement of irrigation scheduling. A regulated (RDI) and a sustained (SDI) deficit irrigation treatment were applied in a âKoroneikiâ olive orchard in Cyprus. Flowering occurred on 11 May 2019 and on 27 April 2021, which was caused by the lower temperatures in 2019. The Kc for the irrigation season, computed from daily water balance observations, was 0.37 in 2019 (38% canopy cover) and 0.41 in 2021 (62% canopy cover). Irrigation treatments did not significantly affect plant morphology and stem water potentials. In âonâ years, shoot elongation ceased early in the season and stem water potential towards the end of September (â4.0 MPa) was lower than in the âoffâ year. Stem water potential recovery in the September of the âoffâ year indicated that irrigation could be less than 35% ETc in early fall. Water savings in RDI were 24â32% in âonâ and 48% in âoffâ years relative to SDI, with no statistically significant effects on olive yield
Performance analysis for capacitive electrical neural interfaces
Neural interfaces will pave the way for novel treatment methods for neural disorders, which are due to communication problems in nervous system. Such disorders include spinal cord injuries, Alzheimer's and Multiple Sclerosis. In this work, we present a novel neural stimulator, which will act as the transmitter part of a neural interface. We perform in detail physical analysis of such a device for the first time, considering the electrostatic and capacitive effects. We also establish the stimulation requirements of the post-synaptic neuron and support our findings with COMSOL simulations. This work will pave the way to the design of more efficient neural stimulators.This work was supported in part by the ERC project MINERVA (ERC-2013-CoG #616922), and the ERC Project MINERGRACE (ERC-2018-PoC #780645)
Hydrodynamic Analysis of a Wave Energy Converter (WEC)
Honorable Mention Winner
The UNF CREW competing in the U.S. Department of Energy 2021 Marine Energy Collegiate Competition developed a Wave Energy Converter (WEC) for quick deployment in disaster relief areas. When natural disasters disable coastal power grids, a WEC can be easily deployed close to shore and serve as a source of electricity. The ocean waves move magnets through a coil wired within the WEC to generate electricity. To initiate the design process, ANSYS AQWA software simulated both the oceanic environment and the deviceâs response in the WECâs testing conditions. AQWA allows the user to change device dimensions easily and optimize the design ahead of physical construction. The resulting WEC proof of concept minimized prototype manufacturing waste and cost by eliminating poor designs in advance. The simulated geometry neglected hollow sections and used unidirectional, regular waves to account for software limitations. The software simulated the WEC for 20 seconds in an oceanic environment with a 40-meter depth and a 0.25-meter amplitude regular wave. Simulations produced graphs and animations describing the forces acting on the WEC as well as the WECâs movement. The animation proved that the WEC reacts well in similar physical testing conditions. Based on the simulation results, the team constructed a 3D model for small-scale testing. Future investigations will involve more complex designs. Research conducted onward will focus on mass-damper systems and contact surfaces provided in the software
Optimization of Power Performance of a Wave Energy Converter
With climate change on the rise, unprecedented dependence on electricity, and an increased incidence of extreme weather, the UNF team participating in the U.S. Department of Energy 2021 Marine Energy Collegiate Competition: Powering the Blue Economy wants to give an alternative solution to provide renewable energy in areas that lose electricity as a result of a natural disaster, or that due to their isolated location cannot use traditional renewable energy sources. This led to the creation of the Osprey C.R.E.W (Cheap Reliable Energy from Waves). The Osprey C.R.E.W. is a wave energy converter that uses the vertical motion of the ocean waves to generate electricity. The principle of energy conversion is Faradayâs Law of Electromagnetic Induction, which states that a magnetic field moving past a conductor will generate electricity. The UNF team has developed a numerical simulation to test how different parameters influence the output and has built three small-scale prototypes that have been tested in a wave tank. A medium-sized prototype and a wave pool are being constructed, with the expectation that the size will also increase the output
Follow-up observations of pulsating subdwarf B stars: Multisite campaigns on PG 1618+563B and PG 0048+091
We present follow-up observations of pulsating subdwarf B (sdB) stars as part
of our efforts to resolve the pulsation spectra for use in asteroseismological
analyses. This paper reports on multisite campaigns of the pulsating sdB stars
PG 1618+563B and PG 0048+091. Data were obtained from observatories placed
around the globe for coverage from all longitudes. For PG 1618+563B, our
five-site campaign uncovered a dichotomy of pulsation states: Early during the
campaign the amplitudes and phases (and perhaps frequencies) were quite
variable while data obtained late in the campaign were able to fully resolve
five stable pulsation frequencies. For PG 0048+091, our five-site campaign
uncovered a plethora of frequencies with short pulsation lifetimes. We find
them to have observed properties consistent with stochastically excited
oscillations, an unexpected result for subdwarf B stars. We discuss our
findings and their impact on subdwarf B asteroseismology.Comment: 50 pages including 17 figures and 10 tables. Accepted for publication
in the Astrophysical Journa
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