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Topic Review
Silvicultural Site Preparation Techniques
Silvicultural site preparation techniques are planned anthropogenic disturbances that are designed to aid in the regeneration and establishment of a new stand of trees.
  • 4.6K
  • 09 Dec 2020
Topic Review
Sustainable Housing in Rwanda
Baked clay bricks (Impunyu) is the dominant wall construction material in Rwanda. Clay deposits in the country’s lowlands are utilized for baked clay bricks. Despite the ongoing campaign, the use of wood by some local brick producers is unfriendly to the environment. Recent research has called for alternative methods in order to reduce the cost and impact on the environment. Earlier efforts with compressed earth blocks were saddled with weight and a substantial use of cement for good surface texture and adequate resistance against surface erosion. This research explored the potentials of using an appropriate dose of clay (from Muhanzi), volcanic light aggregate (Amakoro, (from Musanze)), and cement to produce unbaked shelled compressed earth blocks (SCEB). SCEB is a compressed earth block with an outer shell and inner core of different cement content or materials, compressed into a unit block. The result is a masonry unit with a higher surface resistance, durability, and desirable architectural effect produced with a 60% reduction in cement content. A weight reduction of 12% was achieved with an optimum content of 33% of the volcanic lightweight aggregate. A cost reduction of 25% was recorded over conventional compressed earth brick walls and a 54% over sand-cement block walls. Possible future trends were also identified with appreciable prospects in earthen architecture. 
  • 4.6K
  • 29 Jul 2021
Topic Review
Education of Midwives in Portugal and Spain
In Europe, midwives education, in accordance with the principles of the Bologna Declaration, are based on the pillars defined by Directive 2005/36/CE and by the Munich Declaration. In Portugal, the candidate applies on their own initiative to one of the Higher Education Institutions (HEIs) that provide such training. At the end of the education, students will achieve the master title. In Spain, the candidate sits for a state exam, which is announced annually by each autonomous community, for admission to the specialization.
  • 4.6K
  • 24 Jun 2022
Topic Review
Lipids in Food Flavor Generation
Lipids in food are a source of essential fatty acids and also play a crucial role in flavor and off-flavor development. Lipids contribute to food flavor generation due to their degradation to volatile compounds during food processing, heating/cooking, and storage and/or interactions with other constituents developed from the Maillard reaction and Strecker degradation, among others. The degradation of lipids mainly occurs via autoxidation, photooxidation, and enzymatic oxidation, which produce a myriad of volatile compounds. The oxidation of unsaturated fatty acids generates hydroperoxides that then further break down to odor-active volatile secondary lipid oxidation products including aldehydes, alcohols, and ketones.
  • 4.6K
  • 15 Aug 2022
Topic Review
Language Attrition
Language attrition is the loss of a first or second language or a portion of that language by either a community or an individual. Language attrition is related to multilingualism and language acquisition. Many factors are at play in learning (acquisition) and unlearning (loss) the first and second languages. This can be a simple reversal of learning. In other cases, the type and speed of attrition depends on the individual, also on his or her age and skill level. For the same second language, attrition has been affected differently depending on what is the dominant first language environment. In many cases, attrition could well be case-by-case. Those language learners motivated to keep their first and second languages may very well maintain it, although to do so will likely involve continuous study, or regular use of both.
  • 4.6K
  • 01 Dec 2022
Topic Review
Snow Line
The climatic snow line is the boundary between a snow-covered and snow-free surface. The actual snow line may adjust seasonally, and be either significantly higher in elevation, or lower. The permanent snow line is the level above which snow will lie all year.
  • 4.6K
  • 16 Dec 2022
Topic Review Peer Reviewed
Frederick III of Aragon (1296–1337)
Frederick III of Aragon, King of Sicily (1296–1337). Frederick III of Aragon was the third king of the Aragonese dynasty on the throne of Sicily. He ruled from 1296 to 1337 and he was the only Aragonese king of Sicily who made a significant use of his image. In particular, we have four official (namely, commissioned directly by him or his entourage) representations of him: the royal seal, the billon silver denaro coin, the lost mosaic from the Church of Santa Maria della Valle (known as Badiazza) near Messina, and the mosaic in the Cathedral of Messina.
  • 4.6K
  • 13 Apr 2022
Topic Review
Halt and Catch Fire
In computer engineering, Halt and Catch Fire, known by the assembly mnemonic HCF, is an idiom referring to a computer machine code instruction that causes the computer's central processing unit (CPU) to cease meaningful operation, typically requiring a restart of the computer. It originally referred to a fictitious instruction in IBM System/360 computers, making a joke about its numerous non-obvious instruction mnemonics. With the advent of the MC6800, a design flaw was discovered by the programmers. Due to incomplete opcode decoding, two illegal opcodes, 0x9D and 0xDD, will cause the program counter on the processor to increment endlessly, which renders the processor useless. Those codes have been unofficially named HCF. During the design process of MC6802, engineers originally planned to remove this instruction, but kept it as-is for testing purposes. As a result, HCF was officially recognized as a real instruction. Later, HCF became a humorous catch-all term for instructions that may freeze a processor, including intentional instructions for testing purposes, and unintentional illegal instructions. Some are considered hardware defects, and if the system is shared, a malicious user can execute it to launch a denial-of-service attack. In the case of real instructions, the implication of this expression is that, whereas in most cases in which a CPU executes an unintended instruction (a bug in the code) the computer may still be able to recover, in the case of an HCF instruction there is, by definition, no way for the system to recover without a restart. The expression "catch fire" is a facetious exaggeration of the speed with which the CPU chip would be switching some bus circuits, causing them to overheat and burn.
  • 4.6K
  • 04 Nov 2022
Topic Review
Mekong
The Mekong, or Mekong River, is a trans-boundary river in East Asia and Southeast Asia. It is the world's twelfth longest river and the sixth longest in Asia. Its estimated length is 4,909 km (3,050 mi), and it drains an area of 795,000 km2 (307,000 sq mi), discharging 475 km3 (114 cu mi) of water annually. From the Tibetan Plateau the river runs through China , Myanmar, Laos, Thailand, Cambodia, and Vietnam. The extreme seasonal variations in flow and the presence of rapids and waterfalls in the Mekong make navigation difficult. Even so, the river is a major trade route between western China and Southeast Asia.
  • 4.6K
  • 25 Nov 2022
Topic Review
Textile Recycling
Textile reuse consists of the various methods of prolonging the useful service life of textile products from one owner to another. Renting, trading, swapping, borrowing, and inheriting are commonly practiced, which are facilitated by second-hand stores, garage sales, online stores and flea markets, and charities. On the other hand, textile recycling refers to reprocessing pre-consumer and post-consumer textile waste for use in new textile or non-textile products. Various textile recycling technologies such as fiber regeneration, conversion of textile waste into insulation/building materials, fermentation, anaerobic digestion, composting, and thermal recovery are available and progressively improved. Textile reuse and recycling offer environmental sustainability and can reduce environmental impact by reducing the use of virgin textile fiber and avoiding processes further downstream in the textile product life cycle. 
  • 4.6K
  • 28 Mar 2022
Topic Review
Corneal Regenerative Approach
A transparent cornea is paramount for vision. Corneal opacity is one of the leading causes of blindness. Although conventional corneal transplantation has been successful in recovering patients’ vision, the outcomes are challenged by a global lack of donor tissue availability. Bioengineered corneal tissues are gaining momentum as a new source for corneal wound healing and scar management. Extracellular matrix (ECM)-scaffold-based engineering offers a new perspective on corneal regenerative medicine.
  • 4.6K
  • 11 Aug 2022
Topic Review
Social Class
Social class refers to a hierarchical arrangement of individuals in a society based on factors such as economic status, occupation, education, and cultural capital. It delineates distinct social groups with varying levels of privilege, influencing access to resources, opportunities, and societal advantages.
  • 4.6K
  • 26 Jan 2024
Topic Review
Blood Pressure Sensors
In our unique transdisciplinary approach, we studied the fundamentals of blood pressure and examined its measuring modalities while focusing on their clinical use and sensing principles to identify material functionalities. Then, we carefully reviewed various categories of functional materials utilized in sensor building blocks allowing for comparative analysis of the performance of a wide range of materials throughout the sensor operational-life cycle. Not only this provides essential data to enhance the materials’ properties and optimize their performance, but also, it highlights new perspectives and provides suggestions to develop the next generation pressure sensors for clinical use.
  • 4.6K
  • 10 Apr 2021
Topic Review
Microemulsion Design for Acne Therapy
Acne represents a dermatologic condition with a high prevalence, being characterized by a complex pathogenesis. Its high recurrence frequently encountered in clinical practice will affect the patient’s quality of life. Most of the treatment algorithms require at least one topical formulation, being recommended to be applied on affected areas for a long period. To treat such a versatile skin condition, smart topical vehicles capable of entrap anti-acne compounds can be considered a good option, compared with conventional systems generally used at the moment. In this direction, microemulsions are appreciated for their superior profile in matters of drug delivery, especially for challenging substances with hydrophilic or lipophilic patterns. Designed as transparent and thermodynamically stable systems, with a small number of key ingredients, microemulsion-based formulations were characterized in the present review as unique structures able to pass the skin barrier and sustain a targeted therapy in acne pathology.
  • 4.6K
  • 30 Nov 2020
Topic Review
Tropical Rainforest Climate
File:Koppen-Geiger Map Af present.svgA tropical rainforest climate is a tropical climate usually found within 10 to 15 degrees latitude of the equator, and has at least 60 millimetres (2.4 in) of rainfall every month of the year. Regions with this climate are typically designated Af by the Köppen climate classification. A tropical rainforest climate is typically hot, very humid, and wet.
  • 4.6K
  • 31 Oct 2022
Topic Review
Epoxides Cycloaddition for CO2 Utilization
In the present review (10.3390/pr8050548), CO2 cycloaddition can be seen as a reasonably competent alternative to CO2 transformation, offsetting the high value-added nature by extending material use defer CO2 back to the atmosphere when compared to commodities and fuels such as urea, methanol, and methane.
  • 4.6K
  • 27 Aug 2020
Topic Review
Cry Proteins in Biotechnology
A hallmark of Bacillus thuringiensis bacteria is the formation of one or more parasporal crystal (Cry) proteins during sporulation. The toxicity of these proteins is highly specific to insect larvae, exerting lethal effects in different insect species but not in humans or other mammals. In 1989, a nomenclature was proposed to classify proteins according to their sequence and specificity. In this initial nomenclature, there were only four classes. The first class included proteins with action against Lepidoptera with a size of approximately 130–140 kDa. The second class included smaller proteins (65 kDa) with activity against Lepidoptera and Diptera; this class included only two members: CryIIA and CryIIB. The third class constituted the active toxin against Coleoptera, CryIIIA. The last class was Cry1A, the members of which were closely related: they were called Cry1Aa, Cry1Ab, and Cry1Ac.
  • 4.6K
  • 01 Feb 2022
Topic Review
Comparison Between Esperanto and Interlingua
Esperanto and Interlingua are two planned languages which have taken radically different approaches to the problem of providing an International auxiliary language (IAL). Although they are both classed as IALs, the intellectual bases of Esperanto and Interlingua are quite different. It has been argued that each language is a successful implementation of a particular IAL model. However, in both language communities there is a polemical tradition of using external criteria to critique the perceived opponent language (that is, judging Interlingua by Esperantist criteria and vice versa). In practical use, moreover, language usage in the two communities has sometimes shown convergences despite divergent theory.
  • 4.6K
  • 18 Oct 2022
Topic Review
Type 69 RPG
The Type 69 85mm rocket propelled grenade (RPG), made by Norinco, is a Chinese variant of the Soviet RPG-7. First introduced in 1972, the Type 69 is a common individual anti-tank weapon in service with the PLA. More advanced grenade rounds were developed in the 1980s and 1990s to meet the requirements of modern battlefields. Eventually, the aging Type 69 RPG family was replaced by modern anti-tank weapon systems developed by China such as Type 89 and Type 08.
  • 4.6K
  • 08 Nov 2022
Topic Review
Modern Power Systems
Modern power systems include various technological innovations such as distributed renewable energy sources, energy storage devices, electric vehicle charging stations and advanced communication systems. Since many of these components are owned and managed by private entities, the planning and management of modern power systems is gradually changing, and is becoming a great challenge for utility companies and regulators. 
  • 4.6K
  • 16 Jun 2021
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