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Topic Review
Circular Carbon Economy (CCE)
The circular carbon economy (CCE) system achieves a balance by closing the carbon circle, capturing CO2emissions, and using them economically after their initial linear use. This approach differs in that it does not focus solely on reducing or avoiding the increase in the amounts of carbon. The steady increase in carbon dioxide levels requires increased effort to mitigate their impact.
  • 881
  • 10 Nov 2021
Topic Review
Circular Economy and Financial Aspects
The barriers faced by companies adopting the circular economy in relation to financial performance are defined by (i) the size of the business and the initial investment cost, (ii) difficulties for micro and small companies, (iii) to a more complex structuring of the business, and (iv) greater exposure to risk, as the circular economy is a new concept and is and not as representative as a linear standard system. Thus, there is a need for accounting control of process costs, since resources for different products can have different life cycles. Therefore, factors like financial incentives, subsidies for the projects, and the awareness of nations, companies and consumers are of great importance for the evolution of the circular economy.
  • 602
  • 23 Mar 2022
Topic Review
Circular Economy Implementation
The circular economy, as a promising response to sustainability issues, is a crucible for carefully designed ecofriendly actions and integrative mechanisms in enterprises, households, and societies for the attainment of the desired outcomes. It is in this context that CE strategies are examined, with the use of metrics, indicators, and standards. The desired outcomes of the CE are well embedded and articulated in the sustainable development goals that the UN and its member countries have vowed to achieve along a designated timeline.
  • 456
  • 15 Jun 2021
Topic Review
Circular Economy Principles for Biobased Products
To support progress towards the transition to a circular economy, the ability to measure circularity is essential. The consideration of the role biobased products can play in this transition is however still largely lacking in the development of circularity monitoring approaches. The first step in coming to a suitable monitoring framework for biobased products is to define circular economy principles.
  • 420
  • 27 Oct 2022
Topic Review
Circularity and Energy Production in the Built Environment
Building materials, due to their mass and energy-consuming production processes, drastically increase the embodied energy of construction. There is a significant decrease in environmental impacts results from a shift to recycled materials in the construction phase, as well as from changing the landfill disposal method to recycling. In particular, it was found that the use of recycled building materials (such as recycled cement, metal, concrete, or glass) during the construction phase and recycling disposal methods lead to an overall decrease of impact up to 65%. 
  • 306
  • 16 May 2022
Topic Review
Citizen Science Method
The “citizen science” term is used for environmental monitoring projects or an ongoing program of scientific work in which individual volunteers or networks of volunteers, many of whom may have no specific scientific training, perform or manage air quality research-related tasks such as observation, measurement, data validation, or computation. It reflects a contemporary understanding of science that allows societal engagement through participatory methods. The term "citizen science method" for knowledge transfer purposes can be defined as the four-element study design consisting of preparation, measurements, data analysis, and scientific support components for societal engagement. Each of the four elements is a prerequisite for involving various citizen communities in scientific processes. The method for citizen science is therefore valid if all four of the elements are integrated into the study design.
  • 383
  • 28 Sep 2021
Topic Review
Civitas (Think Tank)
Civitas: The Institute for the Study of Civil Society is a United Kingdom think tank working on issues related to democracy and social policy.
  • 955
  • 22 Nov 2022
Topic Review
Classical Plant Breeding
Classical plant breeding uses deliberate interbreeding (crossing) of closely or distantly related species to produce new crops with desirable properties. Plants are crossed to introduce traits/genes from a particular variety into a new genetic background. For example, a mildew resistant pea may be crossed with a high-yielding but susceptible pea, the goal of the cross being to introduce mildew resistance without losing the high-yield characteristics. Progeny from the cross would then be crossed with the high-yielding parent to ensure that the progeny were most like the high-yielding parent, (backcrossing), the progeny from that cross would be tested for yield and mildew resistance and high-yielding resistant plants would be further developed. Plants may also be crossed with themselves to produce inbred varieties for breeding. Germplasm resources from genebanks have invaluable for classical breeding. Classical breeding relies heavily on the naturally occuring plant life-cycle and homologous recombination to generate genetic diversity and to eliminate undesirable traits. It may also makes use of a variety of artificial laboratory procedures to overcome obstacles to introduction of useful traits from wild species that do not usually exchange genes with the domesticated line. These approaches include in vitro techniques such as protoplast fusion, embryo rescue or mutagenisis (see below) to generate genetic alterations and produce transgenic plants that would not exist in nature. Traits that breeders' have tried to incorporate into crop plants in the last 100 years include: Intraspecific hybridization within a plant species was demonstrated by Charles Darwin and Gregor Mendel, and was further developed by geneticists and plant breeders. In the early 20th century, plant breeders realized that Mendel's findings on the non-random nature of inheritance could be applied to seedling populations produced through deliberate pollinations to predict the frequencies of different types. In 1908, George Harrison Shull described heterosis, also known as hybrid vigor. Heterosis describes the tendency of the progeny of a specific cross to outperform both parents. The detection of the usefulness of heterosis for plant breeding has lead to the development of inbred lines that reveal a heterotic yield advantage when they are crossed. Maize was the first species where heterosis was widely used to produce hybrids. Heterosis made breeders aware of the broad practical value of many genes carried in plant chromosomes even when the identity and trait specified by the paticular genes is unknown - that is that diverse plant Germplasm is generally valuable to the breeder. By the 1920s, statistical methods were developed to analyze gene action and distinguish heritable variation from variation caused by environment. In 1933, another important breeding technique, cytoplasmic male sterility (CMS), developed in maize, was described by Marcus Morton Rhoades. CMS is a maternally inherited trait that makes the plant produce sterile pollen, enabling the production of hybrids and removing the need for detasseling maize plants. The scientific use of Transgenic plants in farming gained impetus in the 1930s when a transgenic wheat variety named Hope bred by E. S. McFadden with a transgene originating in a wild grass saved American wheat growers from devastating stem rust outbreaks. These early breeding techniques resulted in large yield increase in the United States in the early 20th century. Similar yield increases were not produced elsewhere until after World War II, the Green Revolution increased crop production in the developing world in the 1960s. Success stories like Hope and hybrid-vigor made it clear that genetic divesity present in wild-species was of great potential value to plant breeders, and eventially lead to the establisment of Germplasm collections consisting of seed-banks devoted to preservation of potentially useful uncharacterised traits for posterity. Following World War II a number of techniques were developed that allowed plant breeders to hybridize distantly related species, and artificially induce genetic diversity. When distantly related species are crossed, plant breeders make use of a number of plant tissue culture techniques to produce progeny from other wise fruitless mating. Interspecific and intergeneric hybrids are produced from a cross of related species or genera that do not normally sexually reproduce with each other. These crosses are referred to as Wide crosses. The cereal triticale is a wheat and rye hybrid. The first generation created from the cross was sterile, so the cell division inhibitor colchicine was used to double the number of chromosomes in the cell. Cells with an uneven number of chromosomes are sterile. Failure to produce a hybrid may be due to pre- or post-fertilization incompatibility. If fertilization is possible between two species or genera, the hybrid embryo may abort before maturation. If this does occur the embryo resulting from an interspecific or intergeneric cross can sometimes be rescued and cultured to produce a whole plant. Such a method is referred to as Embryo Rescue. This technique has been used to produce new rice for Africa, an interspecific cross of Asian rice (Oryza sativa) and African rice (Oryza glaberrima). Hybrids may also be produced by a technique called protoplast fusion. In this case protoplasts are fused, usually in an electric field. Viable recombinants can be regenerated in culture. Chemical mutagens like EMS and DMSO, radiation and transposons are used to generate mutants with desirable traits to be bred with other cultivars. Classical plant breeders also generate genetic diversity within a species by exploiting a process called somaclonal variation, which occurs in plants produced from tissue culture, particularly plants derived from callus. Induced polyploidy, and the addition or removal of chromosomes using a technique called chromosome engineering also found uses. When a desirable trait has been bred into a species, a number of crosses to the favoured parent are made to make the new plant as similar as the parent as possible. Returning to the example of the mildew resistant pea being crossed with a high-yielding but susceptible pea, to make the mildew resistant progeny of the cross most like the high-yielding parent, the progeny will be crossed back to that parent for several generations (See backcrossing ). This process removes most of the genetic contribution of the mildew resistant parent. Classical breeding is therefore a cyclical process. It should be noted that with classical breeding techniques, the breeder does not know exactly what genes have been introduced to the new cultivars. Some scientists therefore argue that plants produced by classical breeding methods should undergo the same safety testing regime as genetically modified plants. There have been instances where plants bred using classical techniques have been unsuitable for human consumption, for example the poison solanine was accidentally re-introduced into varieties of potato through plant breeding.
  • 1.9K
  • 14 Oct 2022
Topic Review
Classification of Farmland Vegetation
The classification and identification of farmland vegetation includes classification based on vegetation index, spectral bands, multi-source data fusion, artificial intelligence learning, and drone remote sensing.
  • 632
  • 21 Jan 2022
Topic Review
Classified Urban Land Cover Classes
The urban land cover consists of very complex physical materials and surfaces that are constantly having anthropological impacts. The urban surface types are a mosaic of seminatural surfaces such as grass, trees, bare soil, water bodies, and human-made materials of diverse age and composition, such as asphalt, concrete, roof tiles for energy conservation and fire danger, and generally impervious surfaces for urban flooding studies and pollution. The complexity of urban analysis also depends on the scale chosen and its purpose.
  • 1.3K
  • 15 Sep 2021
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