scholarly journals Biopesticide Encapsulation Using Supercritical CO2: A Comprehensive Review and Potential Applications

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4003
Author(s):  
Dário Rodrigues do Nascimento Junior ◽  
Antonio Tabernero ◽  
Elaine Christine de Magalhães Cabral Albuquerque ◽  
Silvio Alexandre Beisl Vieira de Melo
Keyword(s):  
Supercritical Co2 ◽  
Separation Processes ◽  
Nontarget Organisms ◽  
Advantages And Disadvantages ◽  
Supercritical Fluid Technology ◽  
Potential Applications ◽  
Synthetic Pesticides ◽  
Living Organisms ◽  
Carbon Dioxide Co2 ◽  
And Control

As an alternative to synthetic pesticides, natural chemistries from living organisms, are not harmful to nontarget organisms and the environment, can be used as biopesticides, nontarget. However, to reduce the reactivity of active ingredients, avoid undesired reactions, protect from physical stress, and control or lower the release rate, encapsulation processes can be applied to biopesticides. In this review, the advantages and disadvantages of the most common encapsulation processes for biopesticides are discussed. The use of supercritical fluid technology (SFT), mainly carbon dioxide (CO2), to encapsulate biopesticides is highlighted, as they reduce the use of organic solvents, have simpler separation processes, and achieve high-purity particles. This review also presents challenges to be surpassed and the lack of application of SFT for biopesticides in the published literature is discussed to evaluate its potential and prospects.

scholarly journals Extraction of Cecropia Pachystachya Leaves by Supercritical Carbon Dioxide: Kinetics, Phytochemical Characterization, Antibacterial and Antioxidant Activities

2020 ◽  
Vol 8 (4) ◽  
pp. 570
Author(s):  
Jaqueline Hoscheid ◽  
Joice Karina Otenio ◽  
Emerson Luiz Botelho Lourenço ◽  
Elissandro Jair Klein ◽  
Camila Da Silva ◽  
...  
Keyword(s):  
Experimental Data ◽  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Supercritical Co2 ◽  
Antioxidant Activities ◽  
Extraction Yield ◽  
Pharmacological Activities ◽  
Supercritical Fluid Technology ◽  
Carbon Dioxide Co2 ◽  
Supercritical Carbon

Cecropia pachystachya Trécul is popularly known in Brazil as embaúva or embaúba. Pharmacological activities were reported in extant studies including the development of anxiolytic, antidepressant, hypoglycemic, antioxidant, cardiotonic, sedative, anti-inflammatory, antimicrobial and leishmanicidal properties for aqueous and alcoholic extracts prepared by infusion or maceration of C. pachystachya leaves. However, there is a paucity of studies examining extracts of leaves of C. pachystachya obtained by supercritical fluid technology. This study evaluated the extraction of Cecropia pachystachya oil using supercritical carbon dioxide (CO2). Extractions were performed at 35 °C, 45 °C, and 55 °C and 14 MPa, 17 MPa, and 20 MPa. The extraction yield, characteristics of the oil, antioxidant and antibacterial potentials were evaluated. The highest extraction yield obtained from C. pachystachya leaves was 1.48% using supercritical CO2 at 55 °C and 20 MPa. The main identified compounds include terpenoids (ursolic and pomolic acids, squalene and β-sitosterol). The most promising results for antibacterial activity relative to Staphylococcus aureus and antioxidant potentials were observed on the extract obtained at 55 °C and 14 MPa. The mathematical Sovová model satisfactorily represented the experimental data.

Peculiarities of improving interbudgetary relations in conditions of authorities’ decentralization

2020 ◽  
pp. 46-54
Author(s):  
Zenoviy Siryk
Keyword(s):  
Economic Development ◽  
Social Development ◽  
Social Services ◽  
The State ◽  
Major Objective ◽  
Formal Approach ◽  
Advantages And Disadvantages ◽  
Local Areas ◽  
And Control ◽  
Different Levels

Ukraine is a unitary state, yet historically various regions, oblasts, districts, and local areas have different levels of economic development. To secure sustainable economic and social development and provide social services guaranteed by the state for each citizen according to the Constitution, the mechanism of redistribution between revenues and expenditures of oblasts, regions, and territories through the budgets of a higher level is used. The paper aims to research the peculiarities of improving interbudgetary relations in conditions of authorities’ decentralization. The paper defines the nature of interbudgetary relations. The basic and reverse subsidies to Ukraine and Lvivska oblast are analyzed. The advantages and disadvantages the communities face at changing approaches to balancing local budgets are determined. Regulative documents that cover the interbudgetary relations in Ukraine are analyzed. Special attention is paid to the problem of local finances reforming, including the development of interbudgetary relations. The scheme of the economic interbudgetary relations system in Ukraine is developed. The ways to improve the system of interbudgetary relations in Ukraine are suggested. The negative and positive aspects, advantages, and disadvantages of the system of interbudgetary relations in Ukraine require the following improvements. 1. It is necessary to avoid the complete budget alignment in the process of budgets balancing by interbudgetary transfers as the major objective. 2. The interbudgetary transfers should be distributed based on a formal approach. 3. The changes have to be introduced to the calculation of medical and educational subsidies in terms of financial standard of budget provision to avoid the money deficit for coverage of necessary expenditures. 4. There is a need to improve interbudgetary relations at the levels of districts, villages, towns, and cities of district subordination. 5. Improvement of the mechanism of targeted benefits provision, their real evaluation, and control for the use of funds.

Short Review and opinion: New matter properties and applications based on Hybrids Graphene based Metamaterials

2020 ◽  
Vol 04 ◽  
Author(s):  
A. Guillermo Bracamonte
Keyword(s):  
Short Review ◽  
New Materials ◽  
Design And Synthesis ◽  
Chemical Structures ◽  
Current State ◽  
Potential Applications ◽  
Fundamental Research ◽  
Miniaturized Instrumentation ◽  
And Control ◽  
Conductive Properties

: Graphene as Organic material showed special attention due to their electronic and conductive properties. Moreover, its highly conjugated chemical structures and relative easy modification permitted varied design and control of targeted properties and applications. In addition, this Nanomaterial accompanied with pseudo Electromagnetic fields permitted photonics, electronics and Quantum interactions with their surrounding that generated new materials properties. In this context, this short Review, intends to discuss many of these studies related with new materials based on graphene for light and electronic interactions, conductions, and new modes of non-classical light generation. It should be highlighted that these new materials and metamaterials are currently in progress. For this reason it was showed and discussed some representative examples from Fundamental Research with Potential Applications as well as for their incorporations to real Advanced devices and miniaturized instrumentation. In this way, it was proposed this Special issue entitled “Design and synthesis of Hybrids Graphene based Metamaterials”, in order to open and share the knowledge of the Current State of the Art in this Multidisciplinary field.

scholarly journals Hydrodynamic Boundary Layers at Solid Wall—A Tool for Separation of Fine Solids

2021 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Ljubomir Nikolov
Keyword(s):  
Relative Density ◽  
Hydrodynamic Interaction ◽  
Theoretical Study ◽  
Solid Wall ◽  
Separation Processes ◽  
Starting Point ◽  
Potential Applications ◽  
Neutrally Buoyant ◽  
Solid Walls ◽  
Solid Spheres

A theoretical study is performed about the hydrodynamic interaction of fine species entrapped in the boundary layer (BL) at solid wall (plate). The key starting point is the analysis of the disturbance introduced by solid spheres in the background fluid flow. For a neutrally buoyant entity, the type of interaction is determined by the size of the spheres as compared to the thickness of the BL region. The result is granulometric separation of the solids inside the BL domain at the wall. The most important result in view of potential applications concerns the so-called small particles Rp < L/ReL5/4 (ReL is the Reynolds number of the background flow and Rp is the radius of the entrapped sphere). In the case of non-neutrally buoyant particles, gravity interferes with the separation effect. Important factor in this case is the relative density of the solid species as compared to this of the fluid. In view of further practical uses, particles within the range of Δρ/ρ < Fr2/ReL1/2 (Fr is Froude number and Δρ/ρ is the relative density of the entrapped solids) are systematically studied. The trajectories inside the BL region of the captured species are calculated. The obtained data show that there are preferred regions along the wall where the fine solids are detained. The results are important for the assessment of the general efficiency of entrapment and segregation of fine species in the vicinity of solid walls and have high potential for further design of industrial separation processes.

Preparation of Ultra-Fine Powder Using Supercritical Fluids: A Review

2011 ◽  
Vol 148-149 ◽  
pp. 509-515
Author(s):  
De Dong Hu ◽  
Wei Qiang Wang ◽  
Zhi Quan Zhao ◽  
Gui Min Zhang ◽  
Wen Qin Bai ◽  
...  
Keyword(s):  
Ultrafine Particles ◽  
Surface Effect ◽  
Quantum Effect ◽  
Fine Powder ◽  
Control Measures ◽  
Powder Materials ◽  
Supercritical Fluid Technology ◽  
Particle Preparation ◽  
And Control ◽  
Near Future

The size of ultrafine particles ranges between 1~1000nm, including metal, non-metallic, organic, inorganic and biological powder materials. Because of its inherent surface effect, small size effect and quantum effect, it has special optical properties, thermal properties, magnetic properties and mechanical properties which had been widely used in various industrial fields. Supercritical fluid technology has been used to obtain ultra-fine powder of several kind of materials. This work is focused on the systematic production of ultra-fine powder using RESS and SAS process. A systematic summary is made and different measures adopted according to the related circumstances are presented. We also summarize the effect of the process parameters of RESS and SAS process. The ongoing and more extensive research on mechanism and control measures of size, morphology and size distribution of particle should provide a better understanding of particle formation mechanism and achieve the goal of integrated use of different measures to control particle preparation process in the near future.

scholarly journals Mechanisms Applied by Protein Inhibitors to Inhibit Cysteine Proteases

2021 ◽  
Vol 22 (3) ◽  
pp. 997
Author(s):  
Livija Tušar ◽  
Aleksandra Usenik ◽  
Boris Turk ◽  
Dušan Turk
Keyword(s):  
Binding Site ◽  
Structural Information ◽  
General Rule ◽  
Structural Data ◽  
Cysteine Proteases ◽  
Protein Inhibitors ◽  
Active Site Cleft ◽  
Living Organisms ◽  
And Control ◽  
Binding Mechanisms

Protein inhibitors of proteases are an important tool of nature to regulate and control proteolysis in living organisms under physiological and pathological conditions. In this review, we analyzed the mechanisms of inhibition of cysteine proteases on the basis of structural information and compiled kinetic data. The gathered structural data indicate that the protein fold is not a major obstacle for the evolution of a protease inhibitor. It appears that nature can convert almost any starting fold into an inhibitor of a protease. In addition, there appears to be no general rule governing the inhibitory mechanism. The structural data make it clear that the “lock and key” mechanism is a historical concept with limited validity. However, the analysis suggests that the shape of the active site cleft of proteases imposes some restraints. When the S1 binding site is shaped as a pocket buried in the structure of protease, inhibitors can apply substrate-like binding mechanisms. In contrast, when the S1 binding site is in part exposed to solvent, the substrate-like inhibition cannot be employed. It appears that all proteases, with the exception of papain-like proteases, belong to the first group of proteases. Finally, we show a number of examples and provide hints on how to engineer protein inhibitors.

scholarly journals Foaming of rhamnolipids fermentation: impact factors and fermentation strategies

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Zhijin Gong ◽  
Ge Yang ◽  
Chengchuan Che ◽  
Jinfeng Liu ◽  
Meiru Si ◽  
...  
Keyword(s):  
Production Process ◽  
Large Scale ◽  
Commercial Production ◽  
Impact Factors ◽  
Scale Production ◽  
Large Scale Production ◽  
Foaming Behavior ◽  
Production Strategies ◽  
Potential Applications ◽  
And Control

AbstractRhamnolipids have recently attracted considerable attentions because of their excellent biosurfactant performance and potential applications in agriculture, environment, biomedicine, etc., but severe foaming causes the high cost of production, restraining their commercial production and applications. To reduce or eliminate the foaming, numerous explorations have been focused on foaming factors and fermentation strategies, but a systematic summary and discussion are still lacking. Additionally, although these studies have not broken through the bottleneck of foaming, they are conducive to understanding the foaming mechanism and developing more effective rhamnolipids production strategies. Therefore, this review focuses on the effects of fermentation components and control conditions on foaming behavior and fermentation strategies responded to the severe foaming in rhamnolipids fermentation and systematically summarizes 6 impact factors and 9 fermentation strategies. Furthermore, the potentialities of 9 fermentation strategies for large-scale production are discussed and some further strategies are suggested. We hope this review can further facilitate the understanding of foaming factors and fermentation strategies as well as conducive to developing the more effective large-scale production strategies to accelerate the commercial production process of rhamnolipids.

Measuring complex for monitoring carbon dioxide in air

2021 ◽  
pp. 68-71
Author(s):  
Igor M. Ageev ◽  
Yuri M. Rybin
Keyword(s):  
Carbon Dioxide ◽  
High Selectivity ◽  
Distilled Water ◽  
Measuring Systems ◽  
Advantages And Disadvantages ◽  
Measuring Complex ◽  
Co2 Level ◽  
Carbon Dioxide Co2 ◽  
Term Monitoring

The advantages and disadvantages of infrared and electrochemical gas analyzers for carbon dioxide CO2 are described. The possibility of using conductometric sensors with distilled water for monitoring the CO2 content in the air has been investigated. Two identical measuring systems were manufactured, each containing two open-type conductometric cells, a matching device and a personal computer. With the help of these complexes, experiments were carried out on the simultaneous measurement of the CO2 content in the air in two places (a laboratory room and a building in a forest, located at a distance of 15 km from each other) with deliberately different daily dynamics of the CO2 level change. A special experiment was carried out, which made it possible to obtain an estimate of the inertia of conductometric cells and a conversion factor for the values of CO2 content into standard units of measurement. It is shown that the daily dynamics of changes in the electrical conductivity of distilled water in open cells corresponds to the expected dynamics of changes in the CO2 content in the rooms where the measurements were carried out. The operability of the measuring complex and the possibility of creating on its basis a device for long-term monitoring of the CO2 content in the air mixture of gases has been confirmed. The principal high selectivity of the measuring complex to CO2 in relation to other gases of the atmosphere has been established.

EXAMINING EFFECT OF ANIMATION APPLICATIONS ON STUDENT ACHIEVEMENT IN SCIENCE AND TECHNOLOGY COURSE

2015 ◽  
Author(s):  
Sedat Yüksel ◽  
◽  
Mestan Boyaci ◽  
Keyword(s):  
Academic Achievement ◽  
Student Achievement ◽  
Science And Technology ◽  
Control Group ◽  
Constructivist Approach ◽  
8Th Grade ◽  
Living Organisms ◽  
And Control ◽  
Experimental Group ◽  
Technology Course

The aim of this study was to determine whether or not animation applications affect student achievement in science and technology course. For this purpose, effect of constructive approach supported by animations in the instruction of the unit “Living Organisms and Energy” to the 8th grade students on their academic achievement was investigated. This unit was taught to the experimental group using a constructivist approach supported by animations and to the control group using a constructivist approach without animations. For data collection, an achievement was developed and administered to experimental and control groups as pre-tests and post-tests. Collected data was analyzed using t-test and MANOVA. As a result of the research, it was revealed that supporting the constructivist approach with animations was more effective in increasing academic achievement. Key wordThe aim of this study was to determine whether or not animation applications affect student achievement in science and technology course. For this purpose, effect of constructive approach supported by animations in the instruction of the unit “Living Organisms and Energy” to the 8th grade students on their academic achievement was investigated. This unit was taught to the experimental group using a constructivist approach supported by animations and to the control group using a constructivist approach without animations. For data collection, an achievement was developed and administered to experimental and control groups as pre-tests and post-tests. Collected data was analyzed using t-test and MANOVA. As a result of the research, it was revealed that supporting the constructivist approach with animations was more effective in increasing academic achievement. Key words: animation, constructivist science education, teaching supported by computer. s: animation, constructivist science education, teaching supported by computer.

scholarly journals The Potential Use of Isothermal Amplification Assays for In-Field Diagnostics of Plant Pathogens

Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2424
Author(s):  
Aleksandr V. Ivanov ◽  
Irina V. Safenkova ◽  
Anatoly V. Zherdev ◽  
Boris B. Dzantiev
Keyword(s):  
Molecular Diagnostics ◽  
Fungal Pathogens ◽  
Plant Pathogens ◽  
Isothermal Amplification ◽  
Detection Methods ◽  
Nucleic Acid Detection ◽  
Advantages And Disadvantages ◽  
Fungal Phytopathogens ◽  
Highly Sensitive Detection ◽  
And Control

Rapid, sensitive, and timely diagnostics are essential for protecting plants from pathogens. Commonly, PCR techniques are used in laboratories for highly sensitive detection of DNA/RNA from viral, viroid, bacterial, and fungal pathogens of plants. However, using PCR-based methods for in-field diagnostics is a challenge and sometimes nearly impossible. With the advent of isothermal amplification methods, which provide amplification of nucleic acids at a certain temperature and do not require thermocyclic equipment, going beyond the laboratory has become a reality for molecular diagnostics. The amplification stage ceases to be limited by time and instruments. Challenges to solve involve finding suitable approaches for rapid and user-friendly plant preparation and detection of amplicons after amplification. Here, we summarize approaches for in-field diagnostics of phytopathogens based on different types of isothermal amplification and discuss their advantages and disadvantages. In this review, we consider a combination of isothermal amplification methods with extraction and detection methods compatible with in-field phytodiagnostics. Molecular diagnostics in out-of-lab conditions are of particular importance for protecting against viral, bacterial, and fungal phytopathogens in order to quickly prevent and control the spread of disease. We believe that the development of rapid, sensitive, and equipment-free nucleic acid detection methods is the future of phytodiagnostics, and its benefits are already visible.

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