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Current genetic engineering strategies for the production of anti-hypertensive ACEI p...
Carolina Gomes
Diana  Ferreira

Carolina Gomes

and 7 more

January 23, 2020
Hypertension is a major risk factor for cardiovascular diseases, with high prevalence in low- and high-income countries. Among the various antihypertensive therapeutic strategies, synthetic Angiotensin I-converting enzyme inhibitors (ACEI) are one of the most used pharmacological agents. However, their use in hypertension therapy has been linked to various side effects. In recent years considerable research has been performed on the use of food-derived ACEI peptides (ACEIp) as antihypertensive agents. Although promising, the industrial production of these ACEIp through conventional methods, such as chemical synthesis and enzymatic hydrolysis of food proteins, has been proven troublesome and expensive. Limitations to the large-scale production of ACEIp for functional foods and supplements can be overcome by producing the precursors of these peptides in heterologous hosts. Bacterial hosts have been the privileged choice, particularly to test the success of the genetic engineering strategies, but new platforms based on plants and microalgae have also been emerging. This work provides an overview of the state of antihypertensive therapy, focusing on ACEI, illustrates the latest advances on ACEIp research, and describes current genetic engineer-based approaches for the heterologous production of ACEIp for antihypertensive therapy.
A mitophagy-mediated autophagy pathway that triggers apoptotic cell death in non-smal...
jinyan zhu
Baoxia   Li

jinyan zhu

and 7 more

January 22, 2020
Norcantharidin (NCTD) is a traditional Chinese medicine (TCM) that has been used for over 2000 years to treat many diseases. It can inhibit proliferation and induce apoptosis in multiple types of cancer cells. However, the anticancer activities of NCTD in non-small cell lung cancer (NSCLC) cells, and its underlying mechanisms, have not been investigated. In this study, NCTD suppressed the growth and proliferation of A549 non-small cell lung cancer cells in a dose-dependent manner, apparently by reducing the mitochondrial membrane potential and inducing G2/M phase arrest. NCTD induced apoptosis by increasing the ratio of Bax/Bcl-2 and Bax/Mcl-1 and activating caspase-3/9-dependent mitochondrial pathways. Treatment with NCTD induced significant mitophagy and autophagy, as the demonstrated by accumulation of punctate LC3 in the cytoplasm and the characteristic clustering of the mitochondria around the nucleus, increasing the conversion of LC3-I to LC3-II and reducing the protein expression of p62. In addition, we also observed an increase in p-AMPK, p-JNK and p-c-jun and decrease in p-AKT and mTOR. In conclusion, our results demonstrate that NCTD can reduce the mitochondrial membrane potential and subsequently increase cellular autophagy and apoptosis; the AMPK/mTOR/ULK1, JNK and Akt/mTOR signaling pathways were involved in these processes. Thus, the traditional Chinese medicine NCTD could be a novel therapeutic for treating NSCLC cells.
Sustainable Development and Risk Management in Road Construction Industry in Nigeria
Adegboyega Odumade
Mercy Urokor

Adegboyega Odumade

and 2 more

January 22, 2020
Civil Engineering projects which include road construction pose a significant amount of risk due to the several activities involved, its coverage over a wide expanse of land and threat from underground conditions. Risk is defined as the chance of something happening that will have an impact on objectives, and this can be either positive or negative. Risk in road construction stem from the conception till usage and has significant effect on any one of the aspects of a project namely cost, quality, time or scope of the project. In addition, sources of risk can be in terms of payment, security deposit and retention, time of commencement and completion, variation, delay and cost of delay and liquidated damages. Size can be one of the major causes of risk; so can changes in political or commercial planning. Early understanding of the risks involved in a project will help project managers to reduce its impacts and complete the project in a sustainable and more efficient manner. This can be achieved through proper Risk Management. Risk Management entails identification, analysis and application of methods to reduce the identified risk. This study focuses on sustainable risk management for road construction projects, taking South east geopolitical zone of Nigeria as case study. The method involved primary data collection using questionnaire survey and data analysis using statistical models. This study establishes that program evaluation review technique is the most effective risk management practice in Nigeria and conforms to sustainable development practices in addition to analytical hierarchy and probability impact methods. The study would help project managers understand anticipated risks in road projects, better estimate risks prior to the commencement of any project and allows them to develop proper mitigation measures at an early stage of a project.
Co-occurrence is not evidence of ecological interaction
F. Guillaume Blanchet
Kevin Cazelles

F. Guillaume Blanchet

and 2 more

January 22, 2020
There is a rich amount of information in co-occurrence data that could be used to understand community assembly. This proposition first envisioned by Forbes (1907) and then Diamond (1975) prompted the development of numerous modelling approaches (e.g. null model analysis, co-occurrence networks and, more recently, joint species distribution models). Both theory and experimental evidence support the idea that ecological interactions may affect co-occurrence, but it remains unclear to what extent the signal of interaction can be captured in observational data. The time is now ripe to step back from the statistical developments and critically assess whether co-occurrence data really is a proxy for ecological interactions. In this paper we present a series of arguments based on probability, sampling, food web and coexistence theories supporting that significant spatial associations between species (or the lack of) is a poor proxy for ecological interactions. We discuss appropriate interpretations of co-occurrence, along with potential avenues to extract as much information as possible from such data.
Integration of Ion Exchange Resin Materials into Downstream-Processing of an Imine Re...
Lars-Erik Meyer
Henrike Brundiek

Lars-Erik Meyer

and 2 more

January 22, 2020
In this study an ion exchange resin-based downstream-processing approach for imine reductase (IRED)-catalyzed reactions was investigated. As a model reaction, 2 methylpyrroline was converted to its corresponding product (S)-2-methylpyrrolodine with >99% of conversion by the (S)-selective IRED from Paenibacillus elgii B69. Under optimized reaction conditions full conversion was achieved using a substrate concentration of 150 mmol·L-1 and 500 mmol·L-1 of D-glucose. Seven commercially available cation and anion exchange resins were studied with respect to their ability to recover the product from the reaction solution. Without any pre-treatment, cation exchange resins Amberlite IR-120(H), IRN-150, Dowex Monosphere 650C and Dowex Marathon MSC showed high capacities (up to >90%). A 150 mL-preparative-scale reaction was performed yielding ca. 1 g product with >99% purity. Any further purification steps, e.g. by column chromatography or recrystallization, were not required.
Combined Heat and Power Dynamic Economic Dispatch incorporating pumped hydro energy s...
Chitralekha Jena

Chitralekha Jena

January 14, 2022
Owing to increasing penetration of renewable energy sources, it is mandatory to investigate it’s effect on the combined heat and power dynamic economic dispatch. At the same time , adverse effect is there due to highly intermittent nature and higher rate of outages of these sources . This piece of work proposes squirrel search algorithm (SSA) for solving combined heat and power dynamic economic dispatch (CHPDED) incorporating pumped-storage-hydraulic unit captivating uncertainty and outage of renewable energy sources. A lately developed swarm intelligence algorithm SSA, emulates from the dynamic scavenging behavior of squirrel. The competence of the recommended technique is examined on a test system. Simulation outcomes of the proposed technique is harmonized with those acquired by particle swarm optimization (PSO) and grey wolf optimization (GWO). After comparison, a conclusion was made presenting SSA technique conferring with good-quality solution than other techniques.
Many Body Response of Benzene at Monolayer MoS2: Van der Waals interactions and spect...
Alina Umerbekova
Michele Pavanello

Alina Umerbekova

and 1 more

January 22, 2020
Models of surface enhancement of molecular electronic response properties are challenging for two reasons: (1) molecule-surface interactions require the simultaneous solution of the molecular and the surface dynamic response (a daunting task); (2) when solving for the electronic structure of the combined molecule+surface system, it is not trivial to single out the particular physical effects responsible for enhancement. To attack this problem, in this work we apply a formally exact decomposition of the system’s response function into subsystem contributions by employing subsystem DFT which grants access to dynamic polarizabilities and optical spectra. In order to access information about the interactions between the subsystems, we extend a previously developed subsystem-based adiabatic connection fluctuation-dissipation theorem of DFT to separate the additive from the nonadditive correlation energy and identify the nonadditive correlation as the van der Waals interactions. As an example, we choose benzene adsorbed on monolayer MoS2. We isolate the contributions to the benzene’s dynamic response arising from the interaction with the surface and for the first time, we evaluate the enhancements to the effective C6 coefficients as a function of benzene-MoS2 distance and adsorption site. We also quantify the spectral broadening of the benzene’s electronic excited states due to their interaction with the surface. We find that the broadening has a similar decay law with the molecule-surface distance as the leading van der Waals interactions (i.e., R-6) and that the surface enhancement of dispersion interactions between benzene molecules is less than 5\%, but still large enough (0.5 kcal/mol) to likely play a role in the prediction of interface morphologies.
Computational and experimental analysis of highly isolated double side triple band no...
P PRABHU
Malarvizhi S

P PRABHU

and 1 more

January 22, 2020
In this article, we present a double side highly isolated triple band-notched UWB MIMO antenna for short-range wireless communication applications. The proposed MIMO antenna design provides a UWB band with the notched band at the IEEE INSAT C band satellite communication and WLAN band (4.6–5.9 GHz), the X band uplink and downlink satellite communication (7.70–8.43) and (10.3-10.98 GHz). It has double side placement of polygon-shaped radiating elements, and an inverted L-shaped stub to obtain high isolation between radiating elements. The proposed antenna has a size of 18 × 28 mm2, which operates from 3 to 12 GHz. The antenna characteristics such as isolation between radiating elements, S11/S22, gain, and radiation characteristics are studied. The proposed MIMO antenna has isolation of >19 dB, 0-7.5 dBi peak gain and almost radiation pattern over the entire operating frequency band with pattern diversity. Furthermore, MIMO diversity performance was investigated using an ECC, diversity gain, multiplexing efficiency, TARC, and CCL. The proposed UWB MIMO antenna has very low ECC of 0.0025, and DG of >9.9, over the entire operating band (3-12 GHz). Also, the real-time indoor short-range communication capability of the proposed MIMO antenna demonstrated by using the NI 802.1 framework
Integrated GRACE and GLDAS for Estimating Groundwater Storage potential in Bankura Di...
Srinivas  Bankuru
Sandeep Samantaray

Srinivas Bankuru

and 4 more

January 22, 2020
Groundwater is a significant resource for water uses. Groundwater depletion is becoming a global issue for water sustainability. Many places of Globe are suffering to decrement of groundwater. India is overexploiting this resource for irrigation, urbanization and industrialization. In this study evaluation of groundwater storage potential is taken into consideration for Bankura district, West Bengal. Periodical data observed from November 2007 to January 2017 is perceived for study purposes. Broadly remote sense method is used in this study. In the present work Gravity Recovery and Climate Experiment (GRACE) technique is applied for predicting groundwater changes. With the inclusion of Global Land Data Assimilation Systems (GLDAS), performance predictor implies good results. Estimation shows groundwater depletion is amounting to be an average rate of 0.35cm/year. September 2011 experienced maximum positive groundwater changes with equivalent thickness of 17.6722 cm, whereas in June 2013 the substantial change of depletion is found to be -24.16828 cm. Both observed and estimated groundwater changes are compared and have established the value of correlation coefficient as 0.827.
Study of mechanical behaviour of concrete triple blended with steel fibers, fly ash a...
Mavoori kumar
NIHAR RANJAN MOHANTA

Mavoori kumar

and 3 more

January 22, 2020
Latest advancements has been seen in every industry and there has always been a strong competition in the market amongst industries in term of economy, profits, shares etc. one such industry is construction industry where concrete is the key building substance which is in limelight. Since past, we have seen much advancement in concrete because of the research which is in progress on concrete to come out with a product which should be economical and strong enough to resist all kind of loads. In this research, fly ash and silica fume are used as a replacement for cement and a small percentage of steel fibers were included by volume of concrete. Here, fly ash is replaced by 0%, 15%, 30% and silica fume is replaced by 0%, 6%, 12% and 18% for cement. Initially, a set of concrete specimens were casted with 0%, 15%, 30% fly ash and 0%, 6%, 12% and 18% silica fume with 0% inclusion of steel fibers and experiments were conducted for compressive, flexural and split tensile strength. Secondly, another set of concrete specimens were casted with 0%, 15%, 30% fly ash and 0%, 6%, 12% and 18% silica fume with 0.5% inclusion of steel fibers and tested for the same. Similarly, another set of samples were casted 0%, 15%, 30% fly ash and 0%, 6%, 12% and 18% silica fume with 1% addition of steel fibers and tested to determine the strength parameters of concrete. And it was witnessed that at 15% fly ash and 12% silica fume with 1% steel fiber, compressive strength, split tensile strength and flexural strength were shown a peak value.
Analysis of the Effect Environmental Temperature Change has on the magnetic field Str...
George  Nevard

George Nevard

January 22, 2020
This paper aims to establish the exact relationship between Gauss Level and Temperature for a permanent magnet assembly. Magnetrons require a magnetic field to constrain the thermo-electrons emitted from the cathode to form a space charge cloud. The thermo-electrons would simply dissipate at the earth plane rather than form a space charge cloud without this magnetic field. Hence, to ensure optimum performance and consistency of the magnetron, the magnetic field must be calibrated. To calibrate the magnetic field, electromagnets are commonly used as they are highly flexible but they create additional variables such as cost and complexity. After thorough checks to ensure they have the right magnetic field strength, alternative approach is to use permanent magnets. There is some difficulty is measuring field strength accurately using permanent magnets as they are subject to environmental factors such as temperature which affect their magnetic properties. There is the need to compensate for these environmental factors during measurement to ensure accuracy and therefore correct running of a magnetron. Test data was generated through an experiment which was carried out on a permanent magnet sample cycled in temperature while the magnetic field was measured at periodic intervals. A mathematical model generated from test data can then be used for compensation. The Gauss probe used to measure magnetic field was temperature cycled independently to determine the measurement error and a calibration magnet was cycled to validate the data collected in the first experiment.
Design and Simulation of Phased Array Antenna for 40o Beam Steering at 2.4 GHz
seyed mohsen Mirhosseini

seyed mohsen Mirhosseini

January 22, 2020
In this paper a 1x4 array patch antenna designed for (2.4 GHz) frequency. The microstrip line feed technique was used for feeding antenna and a four-way Wilkinson Power Divider designed and simulated for splitting signals to radiating elements. Phase shifter based on switched line technique applied to steer beam to 40 degree. The substrate that used in this paper as dielectric was FR4 of dielectric constant 4.6 and thickness 1.6mm. Design and simulation process were done by Advanced Design System software (ADS 2017).
It’s all connected: Parasite communities of a wild house mouse population exist in a...
Jonathan Fenn
Andrew Wolfenden

Jonathan Fenn

and 7 more

January 22, 2020
1. Wild animal populations typically harbour multiple parasite species, which can interact in various ways depending on the species involved and the state of the host upon infection. While many pairwise parasite interactions and within-guild parasite communities have been characterised, understanding how an interaction network spanning multiple parasite groups might be mediated has been less commonly explored. 2. We aimed to characterise parasites associations across guilds in a wild population of a model species, allowing for comparisons with existing laboratory-based research, and better understanding of how any observed associations might manifest within the host. 3. We used cross-sectional data from an island population of the house mouse, Mus musculus domesticus, to identify associations between a broad range of parasite species, including blood-borne microparasites, arthropod ectoparasites, and gastrointestinal and hepatic helminths. 4. Every recorded species was found to exist within a framework of positive and negative associations, involving multiple between-guild associations, and with the under-studied helminth species Calodium hepaticum playing a central role. 5. This study highlights the need to account for as many infections as possible when studying naturally infected populations, due to the prevalence of inter-species associations. Various potential mechanisms, including immunological and ecological, are suggested to explain how these associations might occur. Comparisons with analogous laboratory research from the same species are explored. A need for longitudinal study to determine causality of interactions is highlighted.
Novel prostanoid syntons from 5,5-dimethoxytetrachlorocyclopentadiene
Сохраб Исмаилов

Sokhrab Ismailov

January 21, 2020
Novel synthons, based on available 5,5-dimetoxytetrachlorocyclopentadiene, were prepared for cyclopentanoids
 Ideological Bases for Peace, Non-Violence, Tolerance and Human Rights in the Writing...
KANZULIMAN FOUNDATION
ghlmghaus

KANZULIMAN FOUNDATION

and 1 more

June 10, 2020
A document by KANZULIMAN FOUNDATION. Click on the document to view its contents.
Movement behavioral plasticity of benthic diatoms driven by optimal foraging
We-Si  Hu
Mingji Huang

We-Si Hu

and 5 more

January 21, 2020
Adaptive locomotion of living organisms contributes to their competitive abilities and helps maintain their fitness in diverse environments. To date, however, our understanding of searching behavior and its ultimate cause remains poorly understood in ecology and biology. Here, we investigate motion patterns of biofilm-inhabiting marine raphid diatom Navicula arenaria var. rostellata in two-dimensional space. We report that individual Navicula cells display a “circular run-and-reversal” movement behavior at different concentrations of dissolved silicic acid (dSi). We show that gliding motions of cells can be predicted accurately with a universal Langevin model. Our experimental results are consistent with an optimal foraging strategy and a maximized diffusivity of the theoretical outcomes in which both circular-run and reversal behaviors are important ingredients. Our theoretical results suggest that the evolving movement behaviors of diatoms may be driven by optimization of searching behavioral strategy, and predicted behavioral parameters coincide with the experimental observations. These optimized movement behaviors are an evolutionarily stable strategy to cope with environmental complexity.
Electric Field Energy Harvesting from Variable Frequency Voltage Sources for Battery-...
Oswaldo Menendez
Loreto Romero

Oswaldo Menendez

and 2 more

January 21, 2020
Internet of Things (IoT) aims to bring connectivity and integration of power system assets, focusing on active management. To ensure the reliability standards of smart cities, IoT requires a wide range of distributed network of wireless sensor nodes. However, energizing these vast networks is highly complex. This work presents a low-power system for electric field energy harvesting, focusing on smart-city applications (Urban IoTs). In particular, we examined design aspects that maximize energy harvesting efficiency according to mains frequency. Experimental findings disclose that a harvester that works at 5 MHz can deliver up to 11 mJ, in approximately 5 minutes. Since the leakage current of diodes is higher than harvester’s current, we introduce a new management circuit, called serial switch-only rectifier (SSOR). The proposed approach is simulated and experimentally evaluated. Empirical results show that a harvester based on SSOR circuit out-performs a harvester based on a full-bridge rectifier and voltage doubler by collecting more charge, approximately 40%.
Characteristics of a nozzle spray in relation to its application to aeroponics
Tejas Narasegowda
Navneet Kumar

Tejas Narasegowda

and 1 more

January 21, 2020
Aeroponics or Soil-less agriculture is a relatively new and recent type of practice, where plants are grown without soil while nutrient-rich water is provided via an atomized spray system to the suspended roots. Spray nozzles are easy-to-use in supplying water (and fertilizers) to (mainly) the roots and root hairs of the desired crop (or plant) for production. We characterize a spray nozzle delivering water vertically above against the gravity by measuring, experimentally, its (a) spray drift, (b) spray height, (c) maximum spray angle, (d) spray width, and (e) droplets sizes. Experiments were carried out at different inlet pressures and a majority of the above mentioned parameters were obtained by processing the images captured using digital (or high speed) camera, sometimes along a plane lighted by a high-power laser source. We also studied the spray (or jet) behaviour at different vertical heights and different horizontal planes using a unique polythene sponge method. We studied the mass flow rate, the mass of water absorbed, and droplet size dynamics (as a function of time and pressure) using this method. A mathematical model is proposed to understand such flows, whose results matched reasonably well with the experimental values. We believe that this study can be extrapolated to other nozzles (or sprays) to obtain similar characteristic parameters. A study was conducted on the characterization of “Plant-water uptake”. This study hence is critical in selecting the desired spray system for a given canopy. The research conducted here would be crucial in designing an Aeroponic system in a controlled agricultural environment.
Fuzzy control for capacitor voltage balancing in a three-level boost converter using...
mohamadreza samadi
seyed mehdi rakhtala

mohamadreza samadi

and 1 more

January 21, 2020
In this paper, MPPT control in PV systems is used by the FPI method which is an intelligent method. Further, the use of a TLBC as an interface converter instead of a conventional boost converter is examined in the PV system and a new transfer function of TLBC in terms of the mode of switching is verified. The main purpose of this paper is to balance voltage capacitors of TLBC by an intelligent fuzzy method. The rules of this controller are adjusted such that, in case of any disturbance in daylight and solar radiation, it can adjust the duty cycle TLBC, where voltage capacitors become well-adapted by being combined with MPPT controller. The simulation results verify the good performance of the proposed controller. Uncertainty parameters include the surrounding temperature, solar radiation, and output electric charge. The first two cannot be controlled by humans and may suddenly change by atmospheric conditions, while the third may suddenly change by the user and can be controlled by the proposed controller under any conditions. A dramatic change in the resistance electric charge is considered in this paper, where the voltage of capacitors does not have any overshoot or fluctuation. The simulation results verify that the capacitor voltage balance in the region is acceptable.
Modelling and simulation for optimization of a Jatropha oil extraction process line f...
dominic Onimowo

dominic Onimowo

January 21, 2020
Inefficiency in operations management cause wastage of resources and funds. This paper will define and properly describe the supply chain problem, build a representative simulation model, validate it using witness and then find a solution to the problem. The process line was optimised, and the efficiency increased to about 95%.
Experimental and Numerical Analysis of Rheological Properties of Invert Emulsion Mud...
dominic Onimowo

dominic Onimowo

January 21, 2020
Emulsion muds are water based drilling fluids, which contain dispersed oil or synthetic hydrocarbon as an internal phase. Drilling muds are very multifaceted liquids mostly made of up clay suspensions and other materials used as circulatory fluids during well drilling. The ability of drilling fluids, in particular invert emulsion muds to perform their functions, such as removal and transportation of cuttings from the well, lubrication and cooling of drill bits and parts, well wall support and formation fluid containment is all dependent on the rheological properties such as their elasticity, plasticity, viscosity and how they flow and distort. The objective of this paper is to carry out an experimental study on oil based drilling fluid; invert emulsion mud, study its rheological properties, its formulation and how they affect well construction and stability. The mud mixture would also be simulated using Drill Bench.
NUMERICAL ANALYSIS OF A CANTILEVER BEAM AND VALIDATION USING THEORETICAL METHODS WITH...
dominic Onimowo
Emmanuel Onimowo

dominic Onimowo

and 1 more

January 21, 2020
This paper investigates the deflection and bending stress in a cantilever beam of uniform rectangular cross section with a point load using a 3D Finite Element (FE) model. The results are validated using the Bernoulli-Euler’s elastic curve theory equations. The research aims to study and analyse the static analysis of a rectangular beam considered to be isotropic. During this analysis, the displacement is assumed to be small, the material exhibits a linear stress strain relationship i.e.: obeys Hooke’s law, there is no change of magnitude, orientation or distribution of the load applied and the effect of gravity are negligible hence with of the beam is not accounted for in this analysis. The simulation is carried out in the Autodesk Inventor stress analysis environment and validated using theoretical methods after which the effects of point loads on structural integrity and mechanical properties are studied.
TDMA Based Numerical Approach on Modeling of Charge Carrier Transport and Ion Vacancy...
Daniyal Khosh Maram

Daniyal Khosh Maram

January 21, 2020
Drift-diffusion models that account for the motion of both electronic and ionic charges are important tools for explaining the hysteretic behaviour. Furnishing numerical solutions to such models for realistic operating conditions is challenging owing to the extreme values of some of the parameters. We present a finite difference scheme with time step that provides second order accuracy in the mesh spacing. The method is able to use realistic parameters values whilst providing high accuracy. Also, three diagonal matrix approximation (TDMA) method is exploit due to matrix solve simplification. This method is robust and fast way to solve. Ion vacancy density, electron concentration, and hole concentration profiles are calculated in transient time-scale. In following, built-in potential is varied and profiles are illustrated. This approach paves the way to have a better insight of device physics and its related phenomena such as ionic motion, hysteresis.
Neural Network as a Cost Function for EPSO Algorithm in Perovskite Solar Cell Simulat...

Daniyal Khosh Maram

and 1 more

January 21, 2020
A document by Daniyal Khosh Maram. Click on the document to view its contents.
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