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Sci, Volume 3, Issue 1 (March 2021) – 18 articles

Cover Story (view full-size image): Many autochthonic species of fruits still remain in the mountainous regions of Georgia. There are also interesting type pearl species that ripen in late autumn and can be kept under suitable conditions for a year. Khechecuri is one of such pears. It is one of the most historically popular species in Georgia. Traditionally, it has been kept for storage underground in “Churi”, which is a vessel made out of clay. The fruit is very resistant to diseases and has a weak aroma. View this paper.
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Review
The Increase of Soil Organic Matter Reduces Global Warming, Myth or Reality?
Sci 2021, 3(1), 18; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010018 - 08 Mar 2021
Cited by 1 | Viewed by 1285
Abstract
The soil has lost organic matter in the past centuries. Adding organic matter to soils is one of the management practices applied to recover the levels of soil carbon of the past and to improve soil properties. Is it a good practice to [...] Read more.
The soil has lost organic matter in the past centuries. Adding organic matter to soils is one of the management practices applied to recover the levels of soil carbon of the past and to improve soil properties. Is it a good practice to reduce global warming? In fact, one of the practices promoted to combat climate change is increasing soil organic matter. However, the addition of organic residues to the soil could facilitate the liberation of CO2 and wastes could also have no positive effects on soil properties (i.e., pollution). In this sense, what it is important is: (a) to know which is the expected effect of the organic matter added to the soil; (b) how this application alters the soil processes; (c) which are the management practices that should be applied; (d) how much is the real amount of carbon sequester by the soil and; (e) the balance at short and long period after the application of the organic matter. The adequate strategy should be to favour the increment of biologically stabilized soil organic matter considering medium and long time. However, it is necessary to adapt the strategies to the local environmental conditions. Full article
(This article belongs to the Special Issue Feature Papers 2020 Editors' Collection)
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Article
Rainfall and Temperature Trend Analysis by Mann–Kendall Test and Significance for Rainfed Cereal Yields in Northern Togo
Sci 2021, 3(1), 17; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010017 - 06 Mar 2021
Viewed by 1295
Abstract
This study investigates the trend in monthly and annual rainfall, minimum and maximum temperature (Tmin and Tmax) using the Mann–Kendall (MK) test and Sen’s slope (SS) method and evaluates the significance of their variability for maize, sorghum and millet yields [...] Read more.
This study investigates the trend in monthly and annual rainfall, minimum and maximum temperature (Tmin and Tmax) using the Mann–Kendall (MK) test and Sen’s slope (SS) method and evaluates the significance of their variability for maize, sorghum and millet yields in northern Togo employing multiple regression analysis. The historical data of Kara, Niamtougou, Mango and Dapaong weather stations from 1977 to 2012 were used. Four non-parametric methods—Alexandersson’s Standard Normal Homogeneity Test (SNHT), Buishand’s Range Test (BRT), Pettitt’s Test (PT) and Von Neumann’s Ratio Test (VNRT)—were applied to detect homogeneity in the data. For the data which were serially correlated, a modified version of the MK test (pre-whitening) was utilised. Results showed an increasing trend in the annual rainfall in all four locations. However, this trend was only significant at Dapaong (p < 0.1). There was an increasing trend in Tmax at Kara, Mango and Niamtougou, unlike Dapaong where Tmax revealed a significant decreasing trend (p < 0.01). Similarly, there was an increasing trend in Tmin at Kara, Mango and Dapaong, unlike Niamtougou where Tmin showed a non-significant decreasing trend (p > 0.05). Rainfall in Dapaong was found to have increased (7.79 mm/year) more than the other locations such as Kara (2.20 mm/year), Niamtougou (4.57 mm/year) and Mango (0.67 mm). Tmax increased by 0.13, 0.13 and 0.32 °C per decade at Kara, Niamtougou and Mango, respectively, and decreased by 0.20 per decade in Dapaong. Likewise, Tmin increased by 0.07, 0.20 and 0.02 °C per decade at Kara, Mango and Dapaong, respectively, and decreased by 0.01 °C per decade at Niamtougou. Results of multiple regression analysis revealed nonlinear yield responses to changes in rainfall and temperature. Rainfall and temperature variability affects rainfed cereal crops production, but the effects vary across crops. The temperature has a positive effect on maize yield in Kara, Niamtougou and Mango but a negative effect on sorghum in Niamtougou and millet in Dapaong, while rainfall has a negative effect on maize yield in Niamtougou and Dapaong and millet yield in Mango. In all locations, rainfall and temperature variability has a significant effect on the cereal crop yields. There is, therefore, a need to adopt some adaptation strategies for sustainable agricultural production in northern Togo. Full article
(This article belongs to the Special Issue The Impact of Climate Change on All Areas of Knowledge)
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Review
Probable Causes of Alzheimer’s Disease
Sci 2021, 3(1), 16; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010016 - 02 Mar 2021
Viewed by 1195
Abstract
A three-part mechanism is proposed for the induction of Alzheimer’s disease: (1) decreased blood lactic acid; (2) increased blood ceramide and adipokines; (3) decreased blood folic acid. The age-related nature of these mechanisms comes from age-associated decreased muscle mass, increased visceral fat and [...] Read more.
A three-part mechanism is proposed for the induction of Alzheimer’s disease: (1) decreased blood lactic acid; (2) increased blood ceramide and adipokines; (3) decreased blood folic acid. The age-related nature of these mechanisms comes from age-associated decreased muscle mass, increased visceral fat and changes in diet. This mechanism also explains why many people do not develop Alzheimer’s disease. Simple changes in lifestyle and diet can prevent Alzheimer’s disease. Alzheimer’s disease is caused by a cascade of events that culminates in damage to the blood–brain barrier and damage to neurons. The blood–brain barrier keeps toxic molecules out of the brain and retains essential molecules in the brain. Lactic acid is a nutrient to the brain and is produced by exercise. Damage to endothelial cells and pericytes by inadequate lactic acid leads to blood–brain barrier damage and brain damage. Inadequate folate intake and oxidative stress induced by activation of transient receptor potential cation channels and endothelial nitric oxide synthase damage the blood–brain barrier. NAD depletion due to inadequate intake of nicotinamide and alterations in the kynurenine pathway damages neurons. Changes in microRNA levels may be the terminal events that cause neuronal death leading to Alzheimer’s disease. A new mechanism of Alzheimer’s disease induction is presented involving lactic acid, ceramide, IL-1β, tumor necrosis factor α, folate, nicotinamide, kynurenine metabolites and microRNA. Full article
(This article belongs to the Special Issue Alternative Mechanisms of Induction of CNS Diseases)
Article
Modeling Regulation of Economic Sustainability in Energy Systems with Diversified Resources
Sci 2021, 3(1), 15; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010015 - 01 Mar 2021
Cited by 2 | Viewed by 1347
Abstract
The imperfection of theoretical and methodological approaches to regulate the jump process transition when combining differentiated energy resources is a pressing issue. The goal of this paper is to develop a theory and a method to regulate the integration-balancing processes of combining diversified [...] Read more.
The imperfection of theoretical and methodological approaches to regulate the jump process transition when combining differentiated energy resources is a pressing issue. The goal of this paper is to develop a theory and a method to regulate the integration-balancing processes of combining diversified resources. The concept of combining integration and balancing models has been substantiated by methods of transforming multidimensional space and approximating generalized functions that represent jump-like processes. Theoretical and operational-regulatory models of economic sustainability have been developed, substantiating new concepts, patterns, properties, dependencies and indicators of the dynamics of the processes of combination; the optimality conditions for the number of approximations of generalized functions, interpreting the effects of control functions of combining resources, are thus determined. New methods for solving problems have been developed: the organization of the energy technology complex of facilities for enhanced resource diversification and the Sustainable Development Center, improving the quality of managing dynamic processes in terms of combining and diversifying resources. Emphasis is placed on four elements: theoretical and methodological approaches to regulate the jump process transition when combining differentiated energy resources is a pressing issue; the goal of this paper is to develop a theory and a method to regulate the integration-balancing processes of combining diversified resources; the concept of combining integration and balancing models has been substantiated by methods of transforming multidimensional space and approximating generalized functions that represent jump-like processes. Full article
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Article
Identification of Long-Term Behavior of Natural Circulation Loops: A Thresholdless Approach from an Initial Response
Sci 2021, 3(1), 14; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010014 - 15 Feb 2021
Viewed by 1318
Abstract
Natural circulation loop (NCL) systems are buoyancy-driven heat exchangers that are used in various industrial applications. The concept of passive heat exchange in NCL systems is attractive, because there is no need for an externally driven equipment (e.g., a pump) to maintain the [...] Read more.
Natural circulation loop (NCL) systems are buoyancy-driven heat exchangers that are used in various industrial applications. The concept of passive heat exchange in NCL systems is attractive, because there is no need for an externally driven equipment (e.g., a pump) to maintain the fluid circulation. However, relying on buoyancy as the sole driving force may lead to several potential difficulties, one of which is generation of (possibly) time-varying nonlinearities in the dynamical system, where a difference in the time scales of heat transfer and fluid flow causes the flow to change from a steady-state regime to either an oscillatory regime or a flow-reversal regime, both of which are undesirable. In this paper, an algorithm is developed using tools of symbolic time-series analysis (e.g., probabilistic finite state automata (PFSA)) for the purpose of identifying selected regimes of operation in NCL systems using only data from the early transient operation, where the underlying principle is built upon the concept of pattern classification from measurements of fluid-flow dynamics. The proposed method is shown to be capable of identifying the current regime of operation from the initial time response under a given set of operational parameters. The efficacy of regime classification is demonstrated by testing on two datasets, generated from numerical simulation of a MATLAB SimuLink model that has previously been validated with experimental data. The results of the proposed PFSA-based classification are compared with those of a hidden Markov model (HMM) that serves as the baseline. Full article
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Article
Vascular Adhesion Protein 1 Mediates Gut Microbial Flagellin-Induced Inflammation, Leukocyte Infiltration, and Hepatic Steatosis
Sci 2021, 3(1), 13; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010013 - 02 Feb 2021
Viewed by 1129
Abstract
Toll-like receptor 5 ligand, flagellin, and vascular adhesion protein 1 (VAP-1) are involved in non-alcoholic fatty liver disease. This study aimed to determine whether VAP-1 mediates flagellin-induced hepatic fat accumulation. The effects of flagellin on adipocyte VAP-1 expression were first studied in vitro. [...] Read more.
Toll-like receptor 5 ligand, flagellin, and vascular adhesion protein 1 (VAP-1) are involved in non-alcoholic fatty liver disease. This study aimed to determine whether VAP-1 mediates flagellin-induced hepatic fat accumulation. The effects of flagellin on adipocyte VAP-1 expression were first studied in vitro. Then, flagellin (100 ng/mouse) or saline was intraperitoneally injected into C57BL/6J (WT) and C57BL/6-Aoc3-/- (VAP-1 KO) mice on a high-fat diet twice a week every 2 weeks for 10 weeks. After that, the effects on inflammation, insulin signaling, and metabolism were studied in liver and adipose tissues. Hepatic fat was quantified histologically and biochemically. Because flagellin challenge increased VAP-1 expression in human adipocytes, we used VAP-1 KO mice to determine whether VAP-1 regulates the inflammatory and metabolic effects of flagellin in vivo. In mice, VAP-1 mediated flagellin-induced inflammation, leukocyte infiltration, and lipolysis in visceral adipose tissue. Consequently, an increased release of glycerol led to hepatic steatosis in WT, but not in KO mice. Flagellin-induced hepatic fibrosis was not mediated by VAP-1. VAP-1 KO mice harbored more inflammation-related microbes than WT mice, while flagellin did not affect the gut microbiota. Our results suggest that by acting on visceral adipose tissue, flagellin increased leukocyte infiltration that induced lipolysis. Further, the released glycerol participated in hepatic fat accumulation. In conclusion, the results describe that gut microbial flagellin through VAP-1 induced hepatic steatosis. Full article
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Review
Role of Peripheral Immune Cells in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis
Sci 2021, 3(1), 12; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010012 - 01 Feb 2021
Viewed by 1364
Abstract
Multiple sclerosis (MS) is a chronic autoimmune disease that affects the myelination of the neurons present in the central nervous system (CNS). The exact etiology of MS development is unclear, but various environmental and genetic factors might play a role in initiating the [...] Read more.
Multiple sclerosis (MS) is a chronic autoimmune disease that affects the myelination of the neurons present in the central nervous system (CNS). The exact etiology of MS development is unclear, but various environmental and genetic factors might play a role in initiating the disease. Experimental autoimmune encephalomyelitis (EAE) is a mouse model that is used to study the pathophysiology of MS disease as well as the effects of possible therapeutic agents. In addition, autoreactive immune cells trigger an inflammatory process upon the recognition of CNS antigens, which leads to destruction of the neurons. These include innate immune cells such as macrophages, dendritic cells, and natural killer cells. Additionally, the activation and extravasation of adaptive immune cells such as CD4+ T cells into the CNS may lead to further exacerbation of the disease. However, many studies revealed that immune cells could have either a protective or pathological role in MS. In this review, we highlight the roles of innate and adaptive immune cellular and soluble players that contribute to the pathogenesis of MS and EAE, which may be used as potential targets for therapy. Full article
(This article belongs to the Special Issue Novel Therapeutic Modalities for Multiple Sclerosis)
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Review
Endocrine Disrupting Compounds Removal Methods from Wastewater in the United Kingdom: A Review
Sci 2021, 3(1), 11; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010011 - 01 Feb 2021
Cited by 1 | Viewed by 1244
Abstract
Endocrine disrupting compounds (EDCs) are contaminants with estrogenic or androgenic activity that negatively impact human and animal communities. These compounds have become one of the most significant concerns for wastewater treatment in recent decades. Several studies have evaluated EDC removal methods from wastewater [...] Read more.
Endocrine disrupting compounds (EDCs) are contaminants with estrogenic or androgenic activity that negatively impact human and animal communities. These compounds have become one of the most significant concerns for wastewater treatment in recent decades. Several studies have evaluated EDC removal methods from wastewater across the globe, including the United Kingdom (UK). Accordingly, the current study reviews EDC removal methods from municipal/domestic wastewater in the United Kingdom (UK) for the period of 2010–2017. The current study analysed original research articles (250), review articles (52), short communication (43), and other associated documents via the ScienceDirect.com database. A total of 25 published articles, which covered EDC removal methods from UK wastewaters, were reviewed rigorously. The research highlights that despite the relative efficacy of existing chemical and physical methods for removing certain EDCs from wastewater, there is emerging evidence supporting the need for more widespread application of nature-based and biological approaches, particularly the use of biofilms. The analysis reveals that there have been relatively few research studies on EDC removal methods carried out in the UK in the 2010–2017 period. Only four papers addressed the removal of specific endocrine disrupting compounds from UK municipal wastewater, and none of the studies addressed EDC removal by using direct biofilms. Finally, this review suggests that more research is needed to remove EDCs, particularly through the application of biofilms, from municipal wastewater in current scenarios. Full article
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Article
Antioxidant Properties of the Native Khechechuri Pear from Western Georgia
Sci 2021, 3(1), 10; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010010 - 01 Feb 2021
Cited by 1 | Viewed by 1230
Abstract
Khechechuri is an endemic species of a pear spread over one region of Western Georgia, called Adjara. Pears are a dietary source of bioactive components such as polyphenols and triterpenic acid. In addition to highlighting its gastronomic value, the aim of the article [...] Read more.
Khechechuri is an endemic species of a pear spread over one region of Western Georgia, called Adjara. Pears are a dietary source of bioactive components such as polyphenols and triterpenic acid. In addition to highlighting its gastronomic value, the aim of the article was to examine and compare phenolic compounds, flavonoids, catechins, phenolic acids, and antioxidant activities in Khechechuri collected from various villages in the Adjara region, namely Adjaristskali, Merisi, Dandalo, Shuakhevi, and Khulo. Five parts of the fruit, the skin, edible pulp, whole pear (skin + pulp), juice, and pomace, were analyzed and the results compared. Our study indicated that the highest total phenolic content was found in the skin of West Georgian pear types (4650 mg/kg.) Moreover, the pomace showed significant amounts of total phenolic content in each of the Khechechuri samples analyzed. Flavonoids were found in each part of the Khechechuri pears, with the notable exception of the fruit juice. A positive correlation between the total phenolic content and the geographical altitude of where the fruits were collected was observed. Full article
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Editorial
Acknowledgment to Reviewers of Sci in 2020
Sci 2021, 3(1), 9; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010009 - 27 Jan 2021
Cited by 1 | Viewed by 1100
Abstract
Peer review is the driving force of journal development, and reviewers are gatekeepers who ensure that Sci maintains its standards for the high quality of its published papers [...] Full article
Article
Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance
Sci 2021, 3(1), 8; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010008 - 08 Jan 2021
Cited by 1 | Viewed by 1173
Abstract
The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic [...] Read more.
The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a noninvasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects. Full article
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Article
Co-Processing of [Fe(NH2trz)3](2ns)2 and UHMWPE into Materials Combining Spin Crossover and High Mechanical Strength
Sci 2021, 3(1), 7; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010007 - 07 Jan 2021
Viewed by 1033
Abstract
The coordination polymer [Fe(NH2trz)3](2ns)2 (NH2trz = 4-amino-1,2,4-triazole and 2ns = counterion 2-naphthalene sulfonate) exhibits the rare phenomenon of spin crossover in an attractive temperature range, i.e., somewhat above room temperature. Spin crossover in [Fe(NH2 [...] Read more.
The coordination polymer [Fe(NH2trz)3](2ns)2 (NH2trz = 4-amino-1,2,4-triazole and 2ns = counterion 2-naphthalene sulfonate) exhibits the rare phenomenon of spin crossover in an attractive temperature range, i.e., somewhat above room temperature. Spin crossover in [Fe(NH2trz)3](2ns)2 is manifested by thermochromism, which is accompanied by a magnetic transition from diamagnetism to paramagnetism. However, [Fe(NH2trz)3](2ns)2 is brittle and difficult to process, which limits its use. In this study, we show that [Fe(NH2trz)3](2ns)2 can be co-processed with ultrahigh molecular weight polyethylene (UHMWPE), which possesses outstanding mechanical properties, particularly when tensile-drawn. Therefore, [Fe(NH2trz)3](2ns)2–UHMWPE blends were gel-processed by extrusion, employing a relatively poor solvent, which has recently been shown to offer advantages compared to good solvents. Uniform and flexible films, ribbons and fibers with [Fe(NH2trz)3](2ns)2 fractions as high as 33.3% m/m were obtained that could be readily drawn. Spin crossover in the coordination polymer is retained in these materials, as evident from their thermochromism. The tensile strength and Young’s modulus of the blends exceed those of typical commodity polymers. Thus, the films, ribbons and fibers constitute a special class of multifunctional materials that combine the flexibility and excellent mechanical properties of drawn UHMWPE with the spin crossover behavior of [Fe(NH2trz)3](2ns)2. Full article
(This article belongs to the Special Issue Feature Papers 2020 Editors' Collection)
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Review
LC–NMR for Natural Product Analysis: A Journey from an Academic Curiosity to a Robust Analytical Tool
Sci 2021, 3(1), 6; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010006 - 06 Jan 2021
Cited by 3 | Viewed by 2393
Abstract
Liquid chromatography (LC)–nuclear magnetic resonance (NMR) combines the advantage of the outstanding separation power of liquid chromatography (LC) and the superior structural elucidating capability of nuclear magnetic resonance (NMR). NMR has proved that it is a standout detector for LC by providing maximum [...] Read more.
Liquid chromatography (LC)–nuclear magnetic resonance (NMR) combines the advantage of the outstanding separation power of liquid chromatography (LC) and the superior structural elucidating capability of nuclear magnetic resonance (NMR). NMR has proved that it is a standout detector for LC by providing maximum structural information about plant originated extracts, particularly on the isolating ability of isomeric (same molecular formula) and/or isobaric (same molecular weight) compounds as compared to other detectors. The present review provides an overview of the developmental trends and application of LC–NMR in natural product analysis. The different LC–NMR operational modes are described, and how technical improvements assist in establishing this powerful technique as an important analytical tool in the analysis of complex plant-derived compounds is also highlighted. On-flow, stop-flow and loop-storage modes, as well as the new offline mode LC–solid phase extraction (SPE)–NMR and capillary LC (capLC)–NMR configurations which avoid the ingestion of expensive deuterated solvents throughout the experiment, are mentioned. Utilization of cryogenic probe and microprobe technologies, which are the other important promising approaches for guaranteeing sensitivity, are also described. Concluding remarks and future outlooks are also discussed. Full article
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Review
New Energy Technologies: Microalgae, Photolysis and Airborne Wind Turbines
Sci 2021, 3(1), 5; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010005 - 06 Jan 2021
Viewed by 1099
Abstract
Because of the near-term risk of extreme weather events and other adverse consequences from climate change and, at least in the longer term, global fossil fuel depletion, there is worldwide interest in shifting to noncarbon energy sources, especially renewable energy (RE). Because of [...] Read more.
Because of the near-term risk of extreme weather events and other adverse consequences from climate change and, at least in the longer term, global fossil fuel depletion, there is worldwide interest in shifting to noncarbon energy sources, especially renewable energy (RE). Because of possible limitations on conventional renewable energy sources, researchers have looked for ways of overcoming these shortcomings by introducing radically new energy technologies. The largest RE source today is bioenergy, while solar energy and wind energy are regarded as having by far the largest technical potential. This paper reviews the literature on proposed new technologies for each of these three RE sources: microalgae for bioenergy, photolysis and airborne wind turbines. The main finding is that their proponents have often underestimated the difficulties they face and the time taken for their introduction on a very large scale. Full article
(This article belongs to the Special Issue Power Systems Optimization and Renewable Energies Integration)
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Article
Lasers for Satellite Uplinks and Downlinks
Sci 2021, 3(1), 4; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010004 - 04 Jan 2021
Viewed by 1662
Abstract
The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, and even lasers as weapons (e.g., Airborne Laser). Lasers in the support of [...] Read more.
The use of Light Amplification by Stimulated Emission of Radiation (i.e., LASERs or lasers) by the U.S. Department of Defense is not new and includes laser weapons guidance, laser-aided measurements, and even lasers as weapons (e.g., Airborne Laser). Lasers in the support of telecommunications is also not new. The use of laser light in fiber optics has shattered thoughts on communications bandwidth and throughput. Even the use of lasers in space is no longer new. Lasers are being used for satellite-to-satellite crosslinking. Laser communication can transmit orders-of-magnitude more data using orders-of-magnitude less power and can do so with minimal risk of exposure to the sending and receiving terminals. What is new is using lasers as the uplink and downlink between the terrestrial segment and the space segment of satellite systems. More so, the use of lasers to transmit and receive data between moving terrestrial segments (e.g., ships at sea, airplanes in flight) and geosynchronous satellites is burgeoning. This manuscript examines the technological maturation of employing lasers as the signal carrier for satellite communications linking terrestrial and space systems. The purpose of the manuscript is to develop key performance parameters (KPPs) to inform the U.S. Department of Defense initial capabilities documents (ICDs) for near-future satellite acquisition and development. By appreciating the history and technological challenges of employing lasers, rather than traditional radio frequency sources for satellite uplink and downlink signal carriers, this manuscript recommends ways for the U.S. Department of Defense to employ lasers to transmit and receive high bandwidth, and large-throughput data from moving platforms that need to retain low probabilities of detection, intercept, and exploit (e.g., carrier battle group transiting to a hostile area of operations, unmanned aerial vehicle collecting over adversary areas). The manuscript also intends to identify commercial sector early-adopter fields and those fields likely to adapt to laser employment for transmission and receipt. Full article
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Article
How to Achieve Compliance with GDPR Article 17 in a Hybrid Cloud Environment
Sci 2021, 3(1), 3; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010003 - 04 Jan 2021
Viewed by 1296
Abstract
On 25 May 2018, the General Data Protection Regulation (GDPR) Article 17, the Right to Erasure (“Right to be Forgotten”) came into force, making it vital for organisations to identify, locate and delete all Personally Identifiable Information (PII) where a valid request is [...] Read more.
On 25 May 2018, the General Data Protection Regulation (GDPR) Article 17, the Right to Erasure (“Right to be Forgotten”) came into force, making it vital for organisations to identify, locate and delete all Personally Identifiable Information (PII) where a valid request is received from a data subject to erase their PII and the contractual period has expired. This must be done without undue delay and the organisation must be able to demonstrate that reasonable measures were taken. Failure to comply may incur significant fines, not to mention impact to reputation. Many organisations do not understand their data, and the complexity of a hybrid cloud infrastructure means they do not have the resources to undertake this task. The variety of available tools are quite often unsuitable as they involve restructuring so there is one centralised data repository. This research aims to demonstrate that compliance with GDPR’s Article 17 Right to Erasure (“Right to be Forgotten”) is achievable in a hybrid cloud environment by following a list of recommendations. However, full retrieval, all of the time will not be possible, but we show that small organisations running an ad-hoc hybrid cloud environment can demonstrate that reasonable measures were taken to be Right to Erasure (“Right to be Forgotten”) compliant. Full article
(This article belongs to the Special Issue Feature Papers 2020 Editors' Collection)
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Hypothesis
Are Scientific Models of Life Testable? A Lesson from Simpson’s Paradox
Sci 2021, 3(1), 2; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010002 - 22 Dec 2020
Viewed by 1145
Abstract
We address the need for a model by considering two competing theories regarding the origin of life: (i) the Metabolism First theory, and (ii) the RNA World theory. We discuss two interrelated points, namely: (i) Models are valuable tools for understanding both the [...] Read more.
We address the need for a model by considering two competing theories regarding the origin of life: (i) the Metabolism First theory, and (ii) the RNA World theory. We discuss two interrelated points, namely: (i) Models are valuable tools for understanding both the processes and intricacies of origin-of-life issues, and (ii) Insights from models also help us to evaluate the core objection to origin-of-life theories, called “the inefficiency objection”, which is commonly raised by proponents of both the Metabolism First theory and the RNA World theory against each other. We use Simpson’s Paradox (SP) as a tool for challenging this objection. We will use models in various senses, ranging from taking them as representations of reality to treating them as theories/accounts that provide heuristics for probing reality. In this paper, we will frequently use models and theories interchangeably. Additionally, we investigate Conway’s Game of Life and contrast it with our SP-based approach to emergence-of-life issues. Finally, we discuss some of the consequences of our view. A scientific model is testable in three senses: (i) a logical sense, (ii) a nomological sense, and (iii) a current technological sense. The SP-based model is testable in the first two senses but it is not feasible to test it using current technology. Full article
(This article belongs to the Special Issue Molecules to Microbes)
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Article
Trend Analysis of Temperature Data for the Narayani River Basin, Nepal
Sci 2021, 3(1), 1; https://0-doi-org.brum.beds.ac.uk/10.3390/sci3010001 - 22 Dec 2020
Cited by 1 | Viewed by 1197
Abstract
The study of spatiotemporal variation in temperature is vital to assess changes in climate, especially in the Himalayan region, where the livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, [...] Read more.
The study of spatiotemporal variation in temperature is vital to assess changes in climate, especially in the Himalayan region, where the livelihoods of billions of people living downstream depends on water coming from the melting of snow and glacier ice. To this end, temperature trend analysis is carried out in the Narayani River basin, a major river basin of Nepal, characterized by three climatic regions: tropical, subtropical and alpine. Temperature data from six stations located within the basin were analyzed. The elevation of these stations ranges from 460 to 3800 m a.s.l. and the time period of available temperature data ranges from 1960–2015. Multiple regression and empirical mode decomposition (EMD) methods were applied to fill in missing data and to detect trends. Annual as well as seasonal trends were analyzed and a Mann–Kendall test was employed to test the statistical significance of detected trends. The results indicate significant cooling trends before 1970s, and warming trends after 1970s in the majority of the stations. The warming trends range from 0.028 to 0.035 °C year1 with a mean increasing trend of 0.03 °C year1 after 1971. Seasonal trends show the highest warming trends in the monsoon season, followed by winter and the premonsoon and postmonsoon season. However, the difference in warming rates between different seasons was not significant. An average temperature lapse rate of −0.006 °C m1 with the steepest value (−0.0064 °C m1) in the premonsoon season and the least negative (−0.0052 °C m1) in the winter season was observed for this basin. A comparative analysis of the gap-filled data with freely available global climate dataset show reasonable correlation, thus confirming the suitability of the gap filling methods. Full article
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