Experimental Study of LoRa Transmission over Seawater

Low Power Wide Area Networks (LPWANs) are gaining attention in both academia and industry by offering the possibility of connecting a large number of nodes over extended distances. LoRa is one of the technologies used as a physical layer in such networks. This paper investigates the LoRa links over seawater in two typical scenarios: clear Line-of-Sight (LOS) and obstructed path in two different Industrial, Scientific and Medical (ISM) radio bands: 868 MHz and 434 MHz. We used three different LoRa devices in the experiments: the Own Developed LoRa Transceiver (ODT) and two commercial transceivers. Firstly we investigated transceivers’ Receive Signal Strength Indicator (RSSI) and Signal-to-Noise (SNR) measurement chain linearity and provided correction factors for RSSI to correlate it with actual signal levels received at transceivers’ inputs. Next, we carried out field experiments for three different LoRa Spreading Factors, S F ∈ [ 7 , 10 , 12 ] , within a bandwidth of B W = 125 kHz and Coding Rate C R = 4 / 6 . The experiments showed that LoRa links are fully feasible over seawater at distances at least 22 km long, using only low-cost off-the-shelf rubber duck antennas in LOS path condition in both ISM bands. In addition, we showed that LoRa links can be established over 28 km obstructed LOS oversea path in ISM 434 MHz band, but using costly, higher gain antennas. Furthermore, the laboratory experiments revealed that RSSI is linear in a wide range, up to - 50 dBm, whereas the SNR measurement chain goes into saturation for Received Signal Strength (RSS) values higher than - 100 dBm. These findings enabled accurate interpretation of the results obtained in field experiments.

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RSS-Based Localization and Mobility Evaluation Using a Single NB-IoT Cell

Sensors ◽

10.3390/s20216172 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6172

Author(s):

Thomas Janssen ◽

Rafael Berkvens ◽

Maarten Weyn

Keyword(s):

Low Power ◽

Large Scale ◽

Low Cost ◽

Estimation Error ◽

Signal Strength ◽

Location Estimation ◽

Wide Area Networks ◽

Localization Performance ◽

Cell Reselection ◽

Signals Of Opportunity

Low Power Wide Area Networks (LPWAN) have the ability to localize a mobile transmitter using signals of opportunity, as a low power and low cost alternative to satellite-based solutions. In this paper, we evaluate the accuracy of three localization approaches based on the Received Signal Strength (RSS). More specifically, the performance of a proximity, range-based and optimized fingerprint-based algorithm is evaluated in a large-scale urban environment using a public Narrowband Internet of Things (NB-IoT) network. The results show a mean location estimation error of 340, 320 and 204 m, respectively. During the measurement campaign, we discovered a mobility issue in NB-IoT. In contrast to other LPWAN and cellular technologies which use multiple gateways or cells to locate a device, only a single cell antenna can be used for RSS-based localization in NB-IoT. Therefore, we address this limitation in the current NB-IoT hardware and software by studying the mobility of the cellular-based 3GPP standard in a localization context. Experimental results show that the lack of handover support leads to increased cell reselection time and poor cell sector reliability, which in turn results in reduced localization performance.

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Concentration of Impurities during Melting of Snow Made from Secondary Sewage Effluent

Water Science & Technology ◽

10.2166/wst.1986.0024 ◽

1986 ◽

Vol 18 (2) ◽

pp. 151-156 ◽

Cited By ~ 4

Author(s):

R. Zapf-Gilje ◽

S. O. Russell ◽

D. S. Mavinic

Keyword(s):

Potassium Chloride ◽

Chloride Solution ◽

Laboratory Experiments ◽

Field Experiments ◽

Low Cost ◽

Sewage Effluent ◽

Potassium Chloride Solution ◽

Laboratory Results ◽

Solution Field ◽

Concentration Of Impurities

When snow is made from sewage effluent, the impurities become concentrated in the early melt leaving the later runoff relatively pure. This could provide a low cost method of separating nutrients from secondary sewage effluent. Laboratory experiments showed that the degree of concentration was largely independent of the number of melt freeze cycles or initial concentration of impurity in the snow. The first 20% of melt removed with it 65% of the phosphorus and 90% of the nitrogen from snow made from sewage effluent; and over 90% of potassium chloride from snow made from potassium chloride solution. Field experiments with a salt solution confirmed the laboratory results.

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Control of Winged Waterprimrose (Jussiaea decurrens) and Northern Jointvetch (Aeschynomene virginica) with Fungal Pathogens

Weed Science ◽

10.1017/s0043174500044477 ◽

1979 ◽

Vol 27 (5) ◽

pp. 497-501 ◽

Cited By ~ 46

Author(s):

C. D. Boyette ◽

G. E. Templeton ◽

R. J. Smith

Keyword(s):

Oryza Sativa ◽

Glycine Max ◽

Fungal Pathogens ◽

Liquid Culture ◽

Field Experiments ◽

Colletotrichum Gloeosporioides ◽

Pathogenic Fungus ◽

Field Tests ◽

Wide Range ◽

Growing Region

An indigenous, host-specific, pathogenic fungus that parasitizes winged waterprimrose [Jussiaea decurrens(Walt.) DC.] is endemic in the rice growing region of Arkansas. The fungus was isolated and identified asColletotrichum gloeosporioides(Penz.) Sacc. f.sp. jussiaeae(CGJ). It is highly specific for parasitism of winged waterprimrose and not parasitic on creeping waterprimrose (J. repensL. var.glabrescensKtze.), rice (Oryza sativaL.), soybeans [Glycine max(L.) Merr.], cotton (Gossypium hirsutumL.), or 4 other crops and 13 other weeds. The fungus was physiologically distinct from C.gloeosporioides(Penz.) Sacc. f. sp.aeschynomene(CGA), an endemic anthracnose pathogen of northern jointvetch[Aeschynomene virginica(L.) B.S.P.], as indicated by cross inoculations of both weeds. Culture in the laboratory and inoculation of winged waterprimrose in greenhouse, growth chamber and field experiments indicated that the pathogen was stable, specific, and virulent in a wide range of environments. The pathogen yielded large quantities of spores in liquid culture. It is suitable for control of winged waterprimrose. Winged waterprimrose and northern jointvetch were controlled in greenhouse and field tests by application of spore mixtures of CGJ and CGA at concentrations of 1 to 2 million spores/ml of each fungus in 94 L/ha of water; the fungi did not damage rice or nontarget crops.

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Information and information resources in COVID-19: Awareness, control, and prevention

Journal of Librarianship and Information Science ◽

10.1177/09610006211016519 ◽

2021 ◽

pp. 096100062110165

Author(s):

Mohammadhiwa Abdekhoda ◽

Fatemeh Ranjbaran ◽

Asghar Sattari

Keyword(s):

Low Cost ◽

Information Resources ◽

Age And Gender ◽

Use Of Resources ◽

Strategic Approach ◽

Wide Range ◽

Data Collection Instrument ◽

Control And Prevention ◽

And Gender ◽

And Control

This study was conducted with the aim of evaluating the role of information and information resources in the awareness, control, and prevention of COVID-19. This study was a descriptive-analytical survey in which 450 participants were selected for the study. The data collection instrument was a researcher-made questionnaire. Descriptive and inferential statistics were used to analyze the data through SPSS. The findings show that a wide range of mass media has become well known as information resources for COVID-19. Other findings indicate a significant statistical difference in the rate of using information resources during COVID-19 based on age and gender; however, this difference is not significant regarding the reliability of information resources with regard to age and gender. Health information has an undisputable role in the prevention and control of pandemic diseases such as COVID-19. Providing accurate, reliable, and evidence-based information in a timely manner for the use of resources and information channels related to COVID-19 can be a fast and low-cost strategic approach in confronting this disease.

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Advanced mycelium materials as potential self-growing biomedical scaffolds

Scientific Reports ◽

10.1038/s41598-021-91572-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Maria Elena Antinori ◽

Marco Contardi ◽

Giulia Suarato ◽

Andrea Armirotti ◽

Rosalia Bertorelli ◽

...

Keyword(s):

Tissue Engineering ◽

Low Cost ◽

Direct Interaction ◽

Dermal Fibroblasts ◽

Engineering Systems ◽

Edible Fungi ◽

Avant Garde ◽

Fibrous Network ◽

Body Tissues ◽

Wide Range

AbstractMycelia, the vegetative part of fungi, are emerging as the avant-garde generation of natural, sustainable, and biodegradable materials for a wide range of applications. They are constituted of a self-growing and interconnected fibrous network of elongated cells, and their chemical and physical properties can be adjusted depending on the conditions of growth and the substrate they are fed upon. So far, only extracts and derivatives from mycelia have been evaluated and tested for biomedical applications. In this study, the entire fibrous structures of mycelia of the edible fungi Pleurotus ostreatus and Ganoderma lucidum are presented as self-growing bio-composites that mimic the extracellular matrix of human body tissues, ideal as tissue engineering bio-scaffolds. To this purpose, the two mycelial strains are inactivated by autoclaving after growth, and their morphology, cell wall chemical composition, and hydrodynamical and mechanical features are studied. Finally, their biocompatibility and direct interaction with primary human dermal fibroblasts are investigated. The findings demonstrate the potentiality of mycelia as all-natural and low-cost bio-scaffolds, alternative to the tissue engineering systems currently in place.

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Rheology and Water Absorption Properties of Alginate–Soy Protein Composites

Polymers ◽

10.3390/polym13111807 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1807

Author(s):

Estefanía Álvarez-Castillo ◽

José Manuel Aguilar ◽

Carlos Bengoechea ◽

María Luisa López-Castejón ◽

Antonio Guerrero

Keyword(s):

Soy Protein ◽

Water Solubility ◽

Divalent Cations ◽

Low Cost ◽

Soy Protein Isolate ◽

Protein Isolate ◽

Guluronic Acid ◽

Wide Range ◽

Anionic Polysaccharides ◽

Porous Matrices

Composite materials based on proteins and carbohydrates normally offer improved water solubility, biodegradability, and biocompatibility, which make them attractive for a wide range of applications. Soy protein isolate (SPI) has shown superabsorbent properties that are useful in fields such as agriculture. Alginate salts (ALG) are linear anionic polysaccharides obtained at a low cost from brown algae, displaying a good enough biocompatibility to be considered for medical applications. As alginates are quite hydrophilic, the exchange of ions from guluronic acid present in its molecular structure with divalent cations, particularly Ca2+, may induce its gelation, which would inhibit its solubilization in water. Both biopolymers SPI and ALG were used to produce composites through injection moulding using glycerol (Gly) as a plasticizer. Different biopolymer/plasticizer ratios were employed, and the SPI/ALG ratio within the biopolymer fraction was also varied. Furthermore, composites were immersed in different CaCl2 solutions to inhibit the amount of soluble matter loss and to enhance the mechanical properties of the resulting porous matrices. The main goal of the present work was the development and characterization of green porous matrices with inhibited solubility thanks to the gelation of alginate.

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Optically transparent and very thin structure against electromagnetic pulse (EMP) using metal mesh and saltwater for shielding windows

Scientific Reports ◽

10.1038/s41598-021-80969-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Duy Tung Phan ◽

Chang Won Jung

Keyword(s):

Electromagnetic Pulse ◽

Low Cost ◽

High Energy ◽

Metal Plate ◽

Optical Transparency ◽

Shielding Effectiveness ◽

Concrete Wall ◽

Metal Mesh ◽

Wide Range ◽

Optically Transparent

AbstractAn electromagnetic pulse (EMP) with high energy can damage electronic equipment instantly within a wide range of thousands of kilometers. Generally, a metal plate placed inside a thick concrete wall is used against an EMP, but it is not suitable for an EMP shielding window, which requires not only strong shielding effectiveness (SE) but also optical transparency (OT). In this paper, we propose a very thin and optically transparent structure with excellent SE for EMP shielding window application. The proposed structure consists of a saltwater layer held between two glass substrates and two metal mesh layers on the outside of the glass, with a total thickness of less than 1.5 cm. The SE and OT of the structure are above 80 dB and 45%, respectively, which not only meet the requirement of EMP shielding for military purposes but also retain the procedure of good observation. Moreover, the OT of the structure can be significantly improved using only one metal mesh film (MMF) layer, while the SE is still maintained high to satisfy the required SE for home applicants. With the major advantages of low cost, optical transparency, strong SE, and flexible performance, the proposed structure can be considered a good solution for transparent EMP shielding windows.

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Photocatalytic three-component asymmetric sulfonylation via direct C(sp3)-H functionalization

Nature Communications ◽

10.1038/s41467-021-22690-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shi Cao ◽

Wei Hong ◽

Ziqi Ye ◽

Lei Gong

Keyword(s):

Asymmetric Catalysis ◽

Organic Synthesis ◽

Photochemical Reaction ◽

Low Cost ◽

Bioactive Molecules ◽

Atom Economy ◽

Mild Conditions ◽

Wide Range ◽

Unsaturated Carbonyl Compound ◽

Direct Functionalization

AbstractThe direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is a highly useful process in organic synthesis owing to the low-cost starting materials, the high step and atom economy. Its application to asymmetric catalysis, however, has been scarcely explored. Herein, we disclose our effort toward this goal by incorporation of dual asymmetric photocatalysis by a chiral nickel catalyst and a commercially available organophotocatalyst with a radical relay strategy through sulfur dioxide insertion. Such design leads to the development of three-component asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers. The photochemical reaction of a C(sp3)-H precursor, a SO2 surrogate and a common α,β-unsaturated carbonyl compound proceeds smoothly under mild conditions, delivering a wide range of biologically interesting α-C chiral sulfones with high regio- and enantioselectivity (>50 examples, up to >50:1 rr and 95% ee). This method is applicable to late-stage functionalization of bioactive molecules, and provides an appealing access to enantioenriched compounds starting from the abundant hydrocarbon compounds.

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Glycans in scaffold design in tissue reconstruction

Journal of Bioactive and Compatible Polymers ◽

10.1177/0883911521997847 ◽

2021 ◽

pp. 088391152199784

Author(s):

Nipun Jain ◽

Shashi Singh

Keyword(s):

Cell Attachment ◽

Low Cost ◽

Growth Conditions ◽

Downstream Signaling ◽

Cell Carrier ◽

Wide Range ◽

Proliferation And Differentiation ◽

Different Types ◽

Tissue Reconstruction ◽

A Cell

Development of an artificial tissue by tissue engineering is witnessed to be one of the long lasting clarified solutions for the damaged tissue function restoration. To accomplish this, a scaffold is designed as a cell carrier in which the extracellular matrix (ECM) performs a prominent task of controlling the inoculated cell’s destiny. ECM composition, topography and mechanical properties lead to different types of interactions between cells and ECM components that trigger an assortment of cellular reactions via diverse sensing mechanisms and downstream signaling pathways. The polysaccharides in the form of proteoglycans and glycoproteins yield better outcomes when included in the designed matrices. Glycosaminoglycan (GAG) chains present on proteoglycans show a wide range of operations such as sequestering of critical effector morphogens which encourage proficient nutrient contribution toward the growing stem cells for their development and endurance. In this review we discuss how the glycosylation aspects are of considerable importance in everyday housekeeping functions of a cell especially when placed in a controlled environment under ideal growth conditions. Hydrogels made from these GAG chains have been used extensively as a resorbable material that mimics the natural ECM functions for an efficient control over cell attachment, permeability, viability, proliferation, and differentiation processes. Also the incorporation of non-mammalian polysaccharides can elicit specific receptor responses which authorize the creation of numerous vigorous frameworks while prolonging the low cost and immunogenicity of the substance.

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Burkholderia thailandensis E264 as a promising safe rhamnolipids’ producer towards a sustainable valorization of grape marcs and olive mill pomace

Applied Microbiology and Biotechnology ◽

10.1007/s00253-021-11292-0 ◽

2021 ◽

Author(s):

Alif Chebbi ◽

Massimiliano Tazzari ◽

Cristiana Rizzi ◽

Franco Hernan Gomez Tovar ◽

Sara Villa ◽

...

Keyword(s):

Energy Source ◽

Olive Oil ◽

Low Cost ◽

Carbon Sources ◽

Burkholderia Thailandensis ◽

Rhamnolipid Production ◽

Key Points ◽

Wide Range ◽

Long Chain ◽

Olive Mill

Abstract Within the circular economy framework, our study aims to assess the rhamnolipid production from winery and olive oil residues as low-cost carbon sources by nonpathogenic strains. After evaluating various agricultural residues from those two sectors, Burkholderia thailandensis E264 was found to use the raw soluble fraction of nonfermented (white) grape marcs (NF), as the sole carbon and energy source, and simultaneously, reducing the surface tension to around 35 mN/m. Interestingly, this strain showed a rhamnolipid production up to 1070 mg/L (13.37 mg/g of NF), with a higher purity, on those grape marcs, predominately Rha-Rha C14-C14, in MSM medium. On olive oil residues, the rhamnolipid yield of using olive mill pomace (OMP) at 2% (w/v) was around 300 mg/L (15 mg/g of OMP) with a similar CMC of 500 mg/L. To the best of our knowledge, our study indicated for the first time that a nonpathogenic bacterium is able to produce long-chain rhamnolipids in MSM medium supplemented with winery residues, as sole carbon and energy source. Key points • Winery and olive oil residues are used for producing long-chain rhamnolipids (RLs). • Both higher RL yields and purity were obtained on nonfermented grape marcs as substrates. • Long-chain RLs revealed stabilities over a wide range of pH, temperatures, and salinities

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