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Topic Review
Drug Delivery Technologies for mRNA Vaccines
mRNA vaccine molecules are large (104–106 Da) in size and are negatively charged. They are unable to pass through the lipid bilayer of cell membranes. Naked mRNA would be destroyed and degraded by the nucleases present in the bloodstream. In addition, naked mRNA is also attached and engulfed by immune cells in the tissue and the serum. Methods to deliver mRNA molecules into the cells include techniques such as gene gun, electroporation, and ex vivo transfection. The in vivo methods of delivering mRNA involves transfection of immune or non-immune cells using lipids or transfecting agents.
  • 1.9K
  • 13 Feb 2023
Topic Review
Legume Protease Inhibitors as Biopesticides
Legumes can produce many different molecules in response to the attack of insects, nematodes, molds, bacteria, and viruses. Protease inhibitors (PIs) are proteins produced by legumes that inhibit proteolytic enzymes of phytopathogens, which cannot feed on the amino acids of the plant. Legume’s strategy to avoid phytopathogens can be used to produce biopesticides and eliminate or decrease the use of agrochemicals in agriculture.
  • 1.9K
  • 06 Nov 2020
Topic Review
Bioindicators of Heavy Metals Pollution
       There is a wide interest in the air quality due to the constant development of many industries and technologies, as well as an extensive use of transport, ultimately leading to emissions of atmospheric pollutants. The application of ubiquitous organisms to assess air pollution has developed significantly during the last few decades. Such living organisms are successful indicators of the presence and availability of different contaminants over time. Lichens are a very popular and effective tool in bioimonitoring. They are usually applied by transplanting from unpolluted area to a contaminated one and assessing the bioaccumulation of the pollutants in the lichen tallus. On the other hand, spider webs are a quite new tool used in the biomonitoring, although they seem to be an easy, cheap method of bioindication which could work all-year–round. Thus, the comparison between these two tools (lichens and spider webs) is eligible and very important  for efficient monitoring of air quality.  We decided to compare the way of heavy metals accumulation in spider webs from Agelenidae family (Eratigena atrica and Agelena labyrinthica) and lichens Hypogymnia physodes, exposed for two months. 
  • 1.9K
  • 26 Oct 2020
Topic Review
Hepatitis E Virus
Hepatitis E virus (HEV) (family Hepeviridae) is one of the most common human pathogens, causing acute hepatitis and an increasingly recognized etiological agent in chronic hepatitis and extrahepatic manifestations. Not only the members of the species Orthohepevirus A  (HEV-A) pathogenic to humans but a genetically highly divergent rat origin hepevirus (HEV-C1) in species Orthohepevirus C (HEV-C) is also able to cause zoonotic infection and symptomatic disease (hepatitis) in humans.
  • 1.9K
  • 29 Oct 2020
Topic Review
Chitosan Adsorbent
Chitin is mentioned as the second most abundant and important natural biopolymer in worldwide scale. The main sources for the extraction and exploitation of this natural polysaccharide polymer are crabs and shrimps. Chitosan (poly-β-(1 → 4)-2-amino-2-deoxy-d-glucose) is the most important derivative of chitin and can be used in a wide variety of applications including cosmetics, pharmaceutical and biomedical applications, food, etc., giving this substance high value-added applications. Moreover, chitosan has applications in adsorption because it contains amino and hydroxyl groups in its molecules, and can thus contribute to many possible adsorption interactions between chitosan and pollutants (pharmaceuticals/drugs, metals, phenols, pesticides, etc.). However, it must be noted that one of the most important techniques of decontamination is considered to be adsorption because it is simple, low-cost, and fast. 
  • 1.9K
  • 01 Jun 2021
Topic Review
Biodegradable Packaging Materials
Food packaging is used to protect food products from physical, chemical, or biological stresses in their environment, thereby improving their quality and extending their shelf life. A variety of packaging materials have traditionally been used for this purpose, including plastic, glass, metal, paper, wood, and textiles. Some of these materials, particularly plastics, cause considerable environmental damage during their manufacture and after their disposal. For0 this reason, there has been great interest in developing biodegradable forms of packaging materials that are more sustainable to produce, that rapidly decompose after disposal, and that do not cause as much environmental pollution. These packaging materials can be constructed from biodegradable film-forming materials such as proteins, polysaccharides, and lipids. Moreover, their functional performance can be enhanced by incorporating organic or inorganic nanoparticles or nanofibers. For instance, nano-forms of clay, iron oxide (Fe2O3), titanium dioxide (TiO2), silver (Ag) and zinc oxide (ZnO) can be used (inorganic nanoparticles), as well as nano-forms of chitin and cellulose and their derivatives (organic nanoparticles). The resulting nanocomposites often have enhanced technofunctional characteristics such as improved optical, mechanical and barrier properties, as well as some novel functional attributes, such as antimicrobial and antioxidant activities, that can prolong the shelf life of packaged foods. Moreover, it is possible to incorporate sensing materials into biodegradable films to provide information about the quality, freshness, or safety of packaged foods. 
  • 1.9K
  • 30 Jun 2021
Topic Review
Alarming Systems for Hazardous Gases and Volatile Chemicals
The leakage of hazardous gases and chemical vapors is considered one of the dangerous accidents that can occur in laboratories, workshops, warehouses, and industrial sites that use or store these substances. The early detection and alarming of hazardous gases and volatile chemicals are significant to keep the safety conditions for the people and life forms who are work in and live around these places.
  • 1.9K
  • 15 Dec 2021
Topic Review
Factors Affecting Pedogenic Carbonate Formation and Recrystallization
As a principal part of the atmosphere–lithosphere interface, soil plays a key role in regulating the atmospheric CO2 concentration and global climate. Comprising two major pools (carbonate in soils and bicarbonate in groundwater), soil inorganic carbon (SIC) is deemed as the primary carbon (C) sink and source in areas with low mean annual rainfall. SIC may originate from soil parent material or from the formation of secondary carbonate when divalent cations from an extraneous source are supplied. The latter may result in pedogenic carbonate (PC) formation, increasing soil C content and sequestering atmospheric carbon. Since the sequestration of atmospheric CO2 through formation of pedogenic carbonate is gaining popularity as a method to support climate change mitigation efforts and to claim carbon credits, the mechanisms influencing the formation and migration of pedogenic carbonate need to be well understood.
  • 1.9K
  • 06 Sep 2022
Topic Review
Electrospun Nanofiber-Based Membranes for Water Treatment
Electrospun nanofiber-based membranes (ENMs), benefitting from characteristics such as a higher specific surface area, higher porosity, lower thickness, and possession of attracted broad attention, has allowed it to evolve into a promising candidate rapidly. According to the roles of electrospun nanofiber layers, NMs can be divided into two categories: (i) nanofiber layer serving as a selective layer, (ii) nanofiber layer serving as supporting substrate.
  • 1.9K
  • 19 Sep 2022
Topic Review
List of Intel Pentium M Microprocessors
The Pentium M brand refers to single-core 32-bit mobile CPUs codenamed Banias and Dothan, and targeted at the consumer market of mobile computers.
  • 1.9K
  • 19 Oct 2022
Topic Review
The Golden Verses of Pythagoras
The Golden Verses of Pythagoras (Greek: Χρύσεα Ἔπη, Chrysea Epê; Latin: Aurea Carmina) are a collection of moral exhortations. They comprise 71 lines written in dactylic hexameter verse and are traditionally attributed to Pythagoras. The exact origins of the Golden Verses are unknown and there are varying opinions regarding their dating. It appears that the verses may have been known as early as the third century BCE but their existence as we know them cannot be confirmed prior to the fifth century CE. The Golden Verses enjoyed great popularity and were widely distributed in late antiquity, being often quoted. Their renown persisted during the medieval ages and into the Renaissance. In 1494 the Neoplatonic Greek scholar Constantine Lascaris published in a famous printed edition of his Grammatica, deliberately, the Golden Verses translated into Latin, thereby bringing them to a widespread audience. The Neoplatonists used the Golden Verses as part of their preparatory program of moral instruction, and a number of Neoplatonic commentaries on the verses are extant. The commentary of the Neoplatonist Hierocles of Alexandria on the Golden Verses was first translated into French by André Dacier (1706) and then into English by Nicholas Rowe (1707); a recent English translation is by Schibli (2002). The most recent scholarly edition of the Golden Verses is by Thom (1994), who supplies a new English translation.
  • 1.9K
  • 20 Oct 2022
Topic Review
Spaced Retrieval
Spaced retrieval, also known as expanded retrieval, is a learning technique, which requires users to rehearse information to be learned at different and increasing spaced intervals of time. In testing this type of learning, people are instructed to rehearse a given set of information at a certain time, and each new rehearsal is expected to have a longer period of time between itself and the previous rehearsal or an equal amount of time between rehearsals. At the end of every trial period there is a test phase. Landauer and Bjork first studied this technique of learning in 1978. The study required participants to learn names from flash cards. Prior to learning participants were placed into five different rehearsal types: uniform short, uniform moderate, uniform long, expanding, and contracting. These all indicate the amount and spacing of trials between each test. Uniform trials involve a number of trials between each test stage, but the trial numbers are fixed (e.g. 2-test-2-test-2-test). Contracting rehearsals involve larger intervals of time between the first few trials and the test phase, but eventually the trials decrease in number. Expanding involves starting with trials and tests close together, and as they progress the person would have more time between each trial and test (e.g. 1-test-2-test-3-test). The effectiveness of the rehearsal types was measured by seeing how accurately participants responded during a test phase. Expanding was proven to be the most important because it produced the highest amount of recall during the test period. The data behind this initial research indicated that an increasing space between rehearsals (expanding) would yield a greater percentage of accuracy at test points. Spaced retrieval with expanding intervals is believed to be so effective because with each expanded interval of retrieval it becomes more difficult to retrieve the information because of the time elapsed between test periods; this creates a deeper level of processing of the learned info in long term memory at each point. Another reason that the expanding retrieval model is believed to work so effectively is because the first test happens early on in the rehearsal process. The purpose of this is to increase retrieval success. By having a first test that followed initial learning with a successful retrieval, people are more likely to remember this successful retrieval on following tests. Although expanding retrieval is commonly associated with spaced retrieval, a uniform retrieval schedule is also a form of spaced retrieval procedure. Spaced retrieval is typically studied through the use of memorizing facts. Traditionally speaking, it has not been applied to fields that required some manipulation or thought beyond simple factual/semantic information. A more recent study has shown that spaced retrieval can benefit tasks such as solving math problems. In a study conducted by Pashler, Rohrer, Cepeda, and Carpenter, participants had to learn a simple math principle in either a spaced or massed retrieval schedule. The participants given the spaced retrieval learning tasks showed higher scores on a final test distributed after their final practice session. This is unique in the sense that it shows spaced retrieval can be used to not only remember simple facts or contextual data, but it can also be used in fields, such as math, where manipulation and the use of particular principles or formulas (e.g. y = mx + b) is necessary. These researchers also found that it is beneficial for feedback to be applied when administering the tests. When a participant gave a wrong response, they were likely to get it correct on following tests if the researcher gave them the correct answer after a delayed period. Spaced retrieval is a useful tool for learning that is relevant to many domains such as fact learning or mathematics, and many different tasks (expanding or uniform retrieval). Many studies over the years have contributed to the use and implementation of spaced retrieval, and it still remains a subject of interest for many researchers.
  • 1.9K
  • 02 Dec 2022
Topic Review
Illicium verum Hook f. (Star Anise)
Illicium verum Hook f. (star anise) is considered an important species in Traditional Chinese Medicine and is also used in contemporary medicine in East Asian countries. It occurs in natural habitats in southeastern parts of China and Vietnam, and is cultivated in various regions in China. The raw materials—Anisi stellati fructus and Anisi stellati aetheroleum obtained from this species exhibit expectorant and spasmolytic activities. The European Pharmacopoeia (4th edition) indicates that these raw materials have been used in allopathy since 2002. The biological activities of the above-mentioned raw materials are determined by the presence of valuable secondary metabolites such as monoterpenoids, sesquiterpenoids, phenylpropanoids, and flavonoids. Recent pharmacological studies on fruit extracts and the essential oil of this species have confirmed their antibacterial, antifungal, anti-inflammatory, and antioxidant activities and thus their medicinal and cosmetic value.
  • 1.9K
  • 28 Jan 2022
Topic Review
Rheological Behavior of Cement Paste
The rheological behavior of cement paste displays several complexities such as non-linearity, yielding, time-dependence and chemical changes. The most common testing procedures allowing for the characterization of this behavior have been reported. For flow behavior, the most relevant protocol consists of the application of a ramp sweep (shear rate or shear stress) so that the flow curve (shear stress as a function of the shear rate) is at steady state flow. The structural build-up can be characterized by static yield stress measurements or the SAOS protocol for various resting times. The non-linearity of flow behavior corresponds to a shear-thinning/shear-thickening phenomenon that can be represented by the Herschel–Bulkley model. If the shear-thinning phenomenon can be related to the flocculation state, the origins of shear thickening are not clearly elucidated. Theories based on order–disorder transition, particle clustering, or viscous/inertial regime transition have been developed to explain the appearance of shear thickening. 
  • 1.9K
  • 17 Aug 2023
Topic Review Peer Reviewed
Formative Assessment and Educational Benefits
Evaluation in education is a complex and multifaceted process, linked to teaching and planning. It represents a powerful tool for regulating behaviors, refining actions, and adapting educational interventions to the specific context in which they are implemented. In this evaluation framework, the work aims to highlight the educational value of assessment, considered a moment in which both the teacher and the student are involved in the teaching-learning process. In particular, formative assessment allows you to find essential information to understand the progress of the actions implemented, highlighting strengths and weaknesses to intervene in educational planning. In this sense, it becomes a valid support for both teachers and students as it allows them to monitor the progress of the teaching/learning process. The work is divided into two parts: the first is theoretical, in which the transition from the assessment of learning (summative) to the assessment for learning (formative) is presented; the second is focused on formative assessment and feedback practices. From a methodological perspective, the literature review emphasizes the potential of assessment that involves students both as recipients and active participants through peer assessment. The paper highlights potential and challenges aimed at improving and experimenting with ways to enhance evaluation competence, which prepares students for professional life.
  • 1.9K
  • 22 May 2025
Topic Review
Tannins
There are diverse challenges in the poultry production industry that decrease the productivity and efficiency of poultry production, impair animal welfare, and pose issues to public health. Furthermore, the use of antibiotic growth promoters (AGP) in feed, which have been used to improve the growth performance and gut health of chickens, has been restricted in many countries. Tannins, polyphenolic compounds that precipitate proteins, are considered as alternatives for AGP in feed and provide solutions to mitigate challenges in poultry production due to their antimicrobial, antioxidant, anti-inflammatory and gut health promoting effects. However, because high dosages of tannins have antinutritional effects when fed to poultry, determining appropriate dosages of supplemental tannins is critical for their potential implementation as a solution for the challenges faced in poultry production.
  • 1.9K
  • 11 Jan 2021
Topic Review
Anaerobic Phototrophic Sulfur Bacteria
Phototrophic purple and green sulfur bacteria have been known for a long time. These microorganisms are characterized by using reduced sulfur (S) compounds as electron donors in the process of anoxygenic photosynthesis and are classified into different families based on their morphology, physiological and biochemical characteristics. Representatives of the largest family, the Chromatiaceae—members of which may be observed in nature as a light red coloration of the anaerobic layer of water—were first described in the second half of the 19th century. In contrast, the less numerous Chlorobiaceae family—also referred to as green sulfur bacteria—were isolated later in the second half of the 20th century.
  • 1.9K
  • 24 Jun 2021
Topic Review
False Data Injection Attacks
False data injection attacks (FDIAs), as a covert cyber-attack method, pose a huge challenge to the safe and stable operation of smart grids by illegally hacking into power systems to tamper with measurement data and thus undermine data integrity.
  • 1.9K
  • 06 Apr 2022
Topic Review
Management of Andean Lupin Anthracnose
The lupin (Lupinus mutabilis Sweet) is a legume domesticated and cultivated for more than 4000 years by the pre-Hispanic cultures of the Andean zone. Due to its good taste and protein content, the lupin seed contributes significantly to the food and nutritional security of the Andean population. However, lupin is susceptible to diseases, and of these, anthracnose is the most devastating as it affects the whole crop, including leaves, stems, pods, and seeds. Seed treatment with fungicides reduces transmission from seed to seedling, but it does not eradicate anthracnose. Attention is given to alternative strategies from sowing to harvest to limit this seed borne pathogen as well as to enhance plant resistance and to promote plant growth. For anthracnose management in the field, integrated practices that encompass control of volunteer plants, lupin ontogenetic resistance, and rotation of biocontrol with chemical fungicides at susceptible phenological stages are considered.  
  • 1.9K
  • 12 Apr 2022
Topic Review
Medium-Chain-Length Polyhydroxyalkanoates Production
Polyhydroxyalkanoates (PHAs) are a type of biopolymer developed as intracellular carbon/energy storage materials which have a wide range of material characteristics. PHAs are identified as granular inclusion bodies after extraction from cells, these are becoming popular as prospective replacements for traditional plastics in various applications, including food packaging industries, cultivational fields, scaffold preparation, and biomaterial implants.
  • 1.9K
  • 27 May 2022
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