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Topic Review
Mechanism of seed anaerobic germination
As sessile organisms, flooding/submergence is one of the major abiotic stresses for higher plants, with deleterious effects on their growth and survival. Therefore, flooding/submergence is a large challenge for agriculture in lowland areas worldwide. Long-term flooding/submergence can cause severe hypoxia stress to crop plants and can result in substantial yield loss. Rice has evolved distinct adaptive strategies in response to low oxygen (O2) stress caused by flooding/submergence circumstances. Recently, direct seeding practice has been increasing in popularity due to its advantages of reducing cultivation cost and labor. However, establishment and growth of the seedlings from seed germination under the submergence condition are large obstacles for rice in direct seeding practice. The physiological and molecular regulatory mechanisms underlying tolerant and sensitive phenotypes in rice have been extensively investigated. Here, this review focuses on the progress of recent advances in the studies of the molecular mechanisms and metabolic adaptions underlying anaerobic germination (AG) and coleoptile elongation. Further, we highlight the prospect of introducing quantitative trait loci (QTL) for AG into rice mega varieties to ensure the compatibility of flooding/submergence tolerance traits and yield stability, thereby advancing the direct seeding practice and facilitating future breeding improvement.
  • 4.9K
  • 19 Oct 2020
Topic Review
Lignocellulosic biomass (LC biomass)
      Bioenergy represents energy from biomass and plays an important role in promoting renewable alternatives. LC biomass is one of the most generous renewable bioresources in nature containing lignin, cellulose, and hemicelluloses. Lignocellulosic materials are the best sources used for biofuel production, such as biogas, and include residues from agriculture and forests, energy crops, and municipal and food waste. According to the latest statistical report for biogas, in Europe, almost 72% of the feedstocks used in the anaerobic digestion (AD) process for biogas production come from the agricultural sector, such as energy crops, manure, and other agricultural residues. The main issue of using lignocellulosic (LC) biomass for the biogas production is biomass recalcitrance, which represents biomass resistance to chemical and biological breakdown.
  • 4.9K
  • 17 Aug 2021
Topic Review
Satellite Sandwich Structures
Sandwich panels are widely used in the design of unmanned satellites and, in addition to having a structural function, can often serve as shielding, protecting the satellites’ equipment from hypervelocity impacts (HVI) of orbital debris and micrometeoroids.
  • 4.9K
  • 12 May 2021
Topic Review
Rotating Packed Beds
In this study, a comprehensive review was conducted of the process intensification equipment used for gas absorption processes, which are known as rotating packed beds (RPB) or HiGee contactors. Using centrifugal acceleration in RPBs intensifies the MT coefficient, and this leads to a reduction in the packing volume and energy consumption in comparison with packed beds. The gas velocity and flow area change radially in RPBs; therefore, MT coefficients change from point to point in contactors, but there is no general theory for this, and the prediction of MT coefficients in RPBs is theoretically complicated.
  • 4.9K
  • 11 Aug 2021
Topic Review
Groundwater Withdrawal-Induced Land Subsidence
Land subsidence is probably one of the most evident environmental effects of groundwater pumping. Globally, freshwater demand is the leading cause of this phenomenon. Land subsidence induced by aquifer system drainage can reach total values of up to 14.5 m. The spatial extension of this phenomenon is usually extensive and is often difficult to define clearly. Aquifer compaction contributes to many socio-economic effects and high infrastructure-related damage costs. Currently, many methods are used to analyze aquifer compaction. These include the fundamental relationship between groundwater head and groundwater flow direction, water pressure and aquifer matrix compressibility. Such solutions enable satisfactory modelling results. However, further research is needed to allow more efficient modelling of aquifer compaction. Recently, satellite radar interferometry (InSAR) has contributed to significant progress in monitoring and determining the spatio-temporal land subsidence distributions worldwide. Therefore, implementation of this approach can pave the way to the development of more efficient aquifer compaction models. This entry presents a comprehensive review of models used to predict land surface displacements caused by rock mass drainage, as well as (2) recent advances and (3) a summary of InSAR implementation over recent years to support the aquifer compaction modelling process. Therefore, the study presented would be of benefit to readers who are interested in the topic of interaction between the human population and the hydrogeological system in different regions. The research presented allows readers to better understand the factors, developments and effects of groundwater drainage and thus facilitate large - scale risk assessment and preventive planning.
  • 4.9K
  • 27 Oct 2020
Topic Review
Idolatry in Sikhism
Sikhism prohibits idolatry, in accordance with mainstream Khalsa norms and the teachings of the Sikh Gurus, a position that has been accepted as orthodox. Growing Sikh popular discontent with Gurdwara administration and practices during the 1800s, revivalist movements in the mid-1800s who opposed idol worship like the Nirankaris and the Namdharis (who however have followed a living guru since its inception), and the encroachment of Brahmanical customs in the Golden Temple during that period, led to the establishment of the Singh Sabha Movement in 1873, in which the Tat Khalsa faction, dominant since the early 1880s, pushed to renew and standardize the practice of Sikhism. After a period of political advancement, the Khalsa faction re-established direct control over Gurdwara management over the Udasi and Hindu mahants, who institutionalized idol worship and would eventually identify with the Sanatan Sikhs, who identified with the Brahmanical social structure and considered idol worship as not harmful. The mahants had gained control of Gurdwaras after heavy Mughal persecution forced the Khalsa to relinquish control of the Gurdwaras and vacate the Punjab plains in the 1700s; they were most prominent in the 1800s. The Arya Samaj, opponents of the Sikhs, asserted that many Sikhs accepted idols and their worship within Sikh temples, unlike Khalsa Sikhs who strongly opposed the practice. In 1905, after re-establishing institutional control, the Khalsa managed to have removed the idols installed during the preceding period, as well as ending mahant administration and the practice of other non-Sikh, Brahmanical rituals in the process, considering them "Hindu accretions" and "Brahmanical stranglehold," amidst a major controversy within the Sikh community of that era. The prohibition, state Fenech and McLeod, has also served a means to assert Sikhism differs from Hinduism.
  • 4.9K
  • 04 Nov 2022
Topic Review
Development Progress of TOPCon Solar Cells
In addition to the different technologies of silicon solar cells in crystalline form, TOPCon solar cells have an exceptionally great efficiency of 26%, accomplished by the manufacturing scale technique for industrialization, and have inordinate cell values of 732.3 mV open-circuit voltage (Voc) and a fill factor (FF) of 84.3%. A silicon layer doped with phosphorus and a very thin tunnel oxide form TOPCon. The thickness of tunnel oxide, which is less than 2 nm in the TOPCon cell, primarily affects the electrical properties and efficiency of the cell. 
  • 4.9K
  • 21 Sep 2022
Topic Review
Plasmonic Biosensors
Biosensors have globally been considered as biomedical diagnostic tools required in abundant areas including the development of diseases, detection of viruses, diagnosing ecological pollution, food monitoring, and a wide range of other diagnostic and therapeutic biomedical research. Recently, the broadly emerging and promising technique of plasmonic resonance has proven to provide label-free and highly sensitive real-time analysis when used in biosensing applications.
  • 4.9K
  • 26 Apr 2022
Topic Review
Family of Donald Trump
The family of Donald Trump, the 45th President of the United States, is a prominent American family active in real estate, entertainment, business, and politics. Trump's immediate family circle is the First Family of the United States. They are part of the broader Trump family originating from Germany . Donald Trump's mother, Mary Anne MacLeod, came from the Hebridean island of Lewis, off the west coast of Scotland. Trump has five children (between three wives) and nine grandchildren.
  • 4.9K
  • 27 Nov 2022
Topic Review
Revitalization of Fishing Village Tourism
Fishing villages and oceans offer various resources and include excellent natural environments and unique cultures that can make such villages attractive spaces to meet the health, culture, and environmental needs of individuals. However, as society has developed and the environment has changed, the catch, which is the major source of income in fishing villages, has declined significantly worldwide, making it difficult to address regional economic issues. Fishing villages that have lost their ability to survive are gradually facing extinction, and there are real problems linked to the survival of fishing communities. Rural areas, in a similar manner to fishing villages, are incorporating tourism in regional development in an attempt to solve the crisis of agriculture, which has itself lost the ability to support entire villages. As a result, tourism has come to be recognized as a representative means of revitalizing rural areas. 
  • 4.9K
  • 21 Jul 2021
Topic Review
Coherence
In physics, two wave sources are coherent if their frequency and waveform are identical. Coherence is an ideal property of waves that enables stationary (i.e. temporally or spatially constant) interference. It contains several distinct concepts, which are limiting cases that never quite occur in reality but allow an understanding of the physics of waves, and has become a very important concept in quantum physics. More generally, coherence describes all properties of the correlation between physical quantities of a single wave, or between several waves or wave packets. Interference is the addition, in the mathematical sense, of wave functions. A single wave can interfere with itself, but this is still an addition of two waves (see Young's slits experiment). Constructive or destructive interference are limit cases, and two waves always interfere, even if the result of the addition is complicated or not remarkable. When interfering, two waves can add together to create a wave of greater amplitude than either one (constructive interference) or subtract from each other to create a wave of lesser amplitude than either one (destructive interference), depending on their relative phase. Two waves are said to be coherent if they have a constant relative phase. The amount of coherence can readily be measured by the interference visibility, which looks at the size of the interference fringes relative to the input waves (as the phase offset is varied); a precise mathematical definition of the degree of coherence is given by means of correlation functions. Spatial coherence describes the correlation (or predictable relationship) between waves at different points in space, either lateral or longitudinal. Temporal coherence describes the correlation between waves observed at different moments in time. Both are observed in the Michelson–Morley experiment and Young's interference experiment. Once the fringes are obtained in the Michelson interferometer, when one of the mirrors is moved away gradually from the beam-splitter, the time for the beam to travel increases and the fringes become dull and finally disappear, showing temporal coherence. Similarly, in a double-slit experiment, if the space between the two slits is increased, the coherence dies gradually and finally the fringes disappear, showing spatial coherence. In both cases, the fringe amplitude slowly disappears, as the path difference increases past the coherence length.
  • 4.9K
  • 16 Nov 2022
Topic Review
Panj Takht
A takht, or taḵẖata (Punjabi: ਤਖ਼ਤ) literally means a throne or seat of authority and is a spiritual and temporal centre of Sikhism. There are five Takhts, which are five gurudwaras that have a very special significance for the Sikh community. The first and the most important was established by Guru Hargobind in 1609, 'Akal Takht' (the Throne of the Timeless God) and is just opposite the gate of Harmandir Sahib – The Golden Temple, Amritsar. While the Harmandir Sahib, or Golden Temple, represents Sikh spiritual guidance, the Akal Takht symbolizes the dispensing of justice and temporal activity. It is the highest seat of temporal authority of the Khalsa and the seat of the Sikh religion's earthly authority. There, the Guru held his court and decided matters of military strategy and political policy. Later on, the Sikh Nation (Sarbat Khalsa) took decisions here on matters of peace and war and settled disputes between the various Sikh groups. The Sarangi singers sung the ballads of the Sikh Gurus and warriors at the place and robes of honour (saropas) were awarded to persons who rendered distinguished services of the community of men in general. In December 2010, the Deccan Odyssey train, taken on charter from Government of Maharashtra, started with the aim to have a journey across four Sikh takhts, with a flight by devout and sightseers to the fifth takht (Takht Sri Patna Sahib). A special train named Panj Takht Special train for the pilgrimage of five Sikh takhts, was flagged off on 16 February 2014.
  • 4.9K
  • 24 Nov 2022
Topic Review
Rhizosphere
The rhizosphere serves as a hotspot for diverse microbial activity. It is an intricate ecosystem comprising nutrient-rich soil that surrounds the plant roots, which provides a pool for plant–microbe communication. The term “Rhizomicrobiome” is defined as a microbial community that is present in the rhizosphere. A variety of microorganisms reside within the rhizosphere, including bacteria, fungi, nematodes, protists, and invertebrates. Most of the microbiome studies within the context of rhizosphere signaling have been focused on the bacteria and fungi that make up the major portion of the rhizosphere microbiome.
  • 4.9K
  • 17 May 2022
Topic Review
Dead Cas Systems
The gene editing tool CRISPR-Cas has become the foundation for developing numerous molecular systems used in research and, increasingly, in medical practice. In particular, Cas proteins devoid of nucleolytic activity (dead Cas proteins; dCas) can be used to deliver functional cargo to programmed sites in the genome. In this review, we describe current CRISPR systems used for developing different dCas-based molecular approaches and summarize their most significant applications
  • 4.9K
  • 30 Oct 2020
Topic Review Peer Reviewed
Reinforced Concrete Infilled Frames
Masonry-Infilled Reinforced Concrete Frames are a very widespread structural typology all over the world for civil, strategic or productive uses. The damages due to these masonry panels can be life threatening to humans and can severely impact economic losses, as shown during past earthquakes. In fact, during a seismic event, most victims are caused by the collapse of buildings or due to nonstructural elements. The damage caused by an earthquake on nonstructural elements, i.e., those not belonging to the actual structural body of the building, is important for the purposes of a more general description of the effects and, of course, for economic estimates. In fact, after an earthquake, albeit of a low entity, it is very frequent to find even widespread damages of nonstructural elements causing major inconveniences even if the primary structure has reported minor damages. In recent years, many territories have been hit worldwide by strong seismic sequences, which caused widespread damages to the nonstructural elements and in particular to the masonry internal partitions and the masonry infill panels of the buildings in reinforced concrete, with damage to the floor and out-of-plane expulsions/collapses of single layers. Unfortunately, these critical issues have arisen not only in historic, but also in recent buildings with reinforced concrete, in many cases exhibiting inadequate seismic behavior, only partly attributable to the intrinsic vulnerability of the masonry panels against seismic actions. Such problems are due to the following aspects: lack of attention to construction details in the realization of the construction, use of poor-quality materials, and above all lack of design tools for the infill masonry walls. In 2018, regarding the design of nonstructural elements, the formulation of floor spectra has been recently introduced in Italy. This entry article wants to focus on all these aspects, describing the state of the art, the literature studies and the design problems to be solved.
  • 4.9K
  • 13 Apr 2022
Topic Review
Unmanned Ground Vehicles
Unmanned ground vehicles (UGVs) have great potential in the application of both civilian and military fields, and have become the focus of research in many countries. Environmental perception technology is the foundation of UGVs, which is of great significance to achieve a safer and more efficient performance.
  • 4.9K
  • 22 Feb 2021
Topic Review
Reflexive Governance
Reflexive governance, as a new mode of governance, has been developed as a way to be more inclusive and more reflexive and respond to complex risks. 
  • 4.9K
  • 26 May 2021
Topic Review
Poly (Butylene Succinate) and PBS Copolyesters Degradation
The impact of plastics on the environment can be mitigated by employing biobased and/or biodegradable materials (i.e., bioplastics) instead of the traditional “commodities”. Poly (butylene succinate) (PBS) emerges as one of the most promising alternatives due to its good mechanical, thermal, and barrier properties, making it suitable for use in a wide range of applications. Nevertheless, less information regarding PBS biodegradation is available, as research is still ongoing. PBS degradation methods include hydrolytic degradation, enzymatic degradation, and biodegradation in environmental conditions, such as burial, activated sludge, and compost.
  • 4.9K
  • 22 Mar 2022
Topic Review
Resistance of PVD Coatings
Due to the increasing maintenance costs of hydraulic machines related to the damages caused by cavitation erosion and/or erosion of solid particles, as well as in tribological connections, surface protection of these components is very important. Up to now, numerous investigations of resistance of coatings, mainly nitride coatings, such as CrN, TiN, TiCN, (Ti,Cr)N coatings and multilayer TiN/Ti, ZrN/CrN and TN/(Ti,Al)N coatings, produced by physical vapor deposition (PVD) method using different techniques of deposition, such as magnetron sputtering, arc evaporation or ion plating, to cavitation erosion, solid particle erosion and wear have been made. The results of these investigations, degradation processes and main test devices used are presented in this paper. An effect of deposition of mono- and multi-layer PVD coatings on duration of incubation period, cumulative weight loss and erosion rate, as well as on wear rate and coefficient of friction in tribological tests is discussed. It is shown that PVD coating does not always provide extended incubation time and/or improved resistance to mentioned types of damage. The influence of structure, hardness, residence to plastic deformation and stresses in the coatings on erosion and wear resistance is discussed. In the case of cavitation erosion and solid particle erosion, a limit value of the ratio of hardness (H) to Young’s modulus (E) exists at which the best resistance is gained. In the case of tribological tests, the higher the H/E ratio and the lower the coefficient of friction, the lower the wear rate, but there are also many exceptions
  • 4.9K
  • 13 Oct 2020
Topic Review
Smart City Planning
The smart city concept is established as those “cities with an intelligent economic, institutional, social and physical infrastructure, which ensure the centralization of their citizens in a sustainable environment”, this being a great challenge to achieve.
  • 4.9K
  • 06 Jun 2021
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