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Topic Review
Methods of Lysergic Acid Synthesis
Ergot is the spore form of the fungus Claviceps purpurea. Ergot alkaloids are indole compounds that are biosynthetically derived from L-tryptophan and represent the largest group of fungal nitrogen metabolites found in nature. The common part of ergot alkaloids is lysergic acid. 
  • 2.1K
  • 01 Dec 2022
Topic Review
Functionally Graded Thermal Sprayed Coatings
       The manufactured industrial pieces have often the external surfaces being in contact with harsh environment. The turbine blades are submitted to hot gas, the implanted prostheses to body liquids, etc. The protection of these surfaces can be realized using films and coatings. The latters have an important function of rendering the life in service of industrial piece longer, belong however, generally, to another group of materials with very different properties than the piece itself. For example, ceramic coatings are applied frequently on metal and alloys and some intermediate layers should be added between substrate and top coating. This is the concept of "functionally graded coatings" reviewed for the technology of thermal spraying in present entry basing onto paper Appl. Sci. 2020, 10, 5153; doi:10.3390/app10155153. The excerpt of this paper shows the chapters related to the applications of functionally graded coatings and their perspectives of development together with selected cited references.
  • 2.1K
  • 27 Dec 2020
Topic Review
Cracking
In petrochemistry, petroleum geology and organic chemistry, cracking is the process whereby complex organic molecules such as kerogens or long-chain hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carbon-carbon bonds in the precursors. The rate of cracking and the end products are strongly dependent on the temperature and presence of catalysts. Cracking is the breakdown of a large alkane into smaller, more useful alkenes. Simply put, hydrocarbon cracking is the process of breaking a long chain of hydrocarbons into short ones. This process requires high temperatures. More loosely, outside the field of petroleum chemistry, the term "cracking" is used to describe any type of splitting of molecules under the influence of heat, catalysts and solvents, such as in processes of destructive distillation or pyrolysis. Fluid catalytic cracking produces a high yield of petrol and LPG, while hydrocracking is a major source of jet fuel, diesel fuel, naphtha, and again yields LPG.
  • 2.1K
  • 27 Oct 2022
Topic Review
Allergy and Allergic Diseases Prevention
Prophylactic interventions for the prevention of allergic diseases differ depending on the timing and the stage in the ontogeny of the processes leading from sensitisation to clinical symptoms.  They can be divided into primary, secondary and tertiary prophylaxis.
  • 2.1K
  • 25 Apr 2021
Topic Review
Entrepreneurship in Times of Crisis
Entrepreneurship represents the views, attitudes and actions of an individual that desires to create or extract value from a perceived opportunity. This usually manifests through the individual’s willingness to face risk through the form of starting a business organization. Entrepreneurship plays a key role in transforming the economy and society by stimulating economic development, testing innovative ideas, creating new jobs, and by enriching the quality of life and human existence. 
  • 2.1K
  • 15 Oct 2021
Topic Review
Rare Genetic Syndromes Associated with Autism
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social and communicative skills, behavioral stereotypes, and sensory abnormalities. Its prevalence is one in 54 children, with the number of identified cases rising annually. Atypical sensory processing is one of the key characteristics of autistic people that can have a cascading influence on higher-level functions, such as language or social inference. Behaviorally, sensory abnormalities can present as hypo- and hyperresponsiveness (or hypo- and hyperreactivity). One of potential reasons for this multidirectional deficit is the high heterogeneity of idiopathic ASD (the form of autism where the biological cause of the disease is not identified). 
  • 2.1K
  • 17 May 2022
Topic Review
COVID-19 Effect on Real Estate Investment Trust Returns
Using an extended Fama–French model for real estate investment trust (REIT) returns, this paper examines how the net impact of the COVID-19 pandemic differs from that of recessions. The authors find that, as anticipated, recessions have a negative net impact on office and residential REIT returns but that the COVID-19 pandemic has a positive net influence on industrial REIT returns because of e-commerce and the demand for storage, distribution, and shipping. Contrary to what are anticipated, there are no negative net effects of the COVID-19 pandemic on office and residential REIT returns, perhaps caused by both existing office and residential leases, the percentage rent clause for commercial properties, and the grace period for residential properties during the COVID-19 pandemic. In contrast to moving solely during recessions and the COVID-19 pandemic, the research finds that retail REIT returns fluctuate along with ongoing macro/asset-pricing conditions throughout the boom and bust cycle.
  • 2.1K
  • 30 Aug 2022
Topic Review
Lithium Technologies
Lithium Technologies is a San Francisco-based provider of software that allows businesses to connect with their customers on social media and digital channels. Lithium was founded in 2001 as a spin-out from GX Media, which created technologies for professional rankings and tournaments and now hosts a number of popular gaming sites. The company's founders include Dennis Fong, Lyle Fong, Michel Thouati, Kirk Yokomizo, John Joh, Nader Alizadeh, Michael Yang, and Matt Ayres. The Lithium platform comprises a set of products for digital marketing and social customer support, including Lithium Communities, which act as the hub for a brand's digital conversations; Lithium Response, a social customer care tool; and Lithium Reach a social media management tool. Klout data powers the Lithium platform with its proprietary algorithms and volume of data with over 750M scored profiles." Lithium's SaaS platform combines online customer community applications such as forums, blogs, innovation management, product reviews, and tribal knowledge bases with the broader social web and traditional CRM business processes, resulting in a wide range of online customer interaction methods. Stemming from its gaming roots, the platform incorporates elaborate rating systems for contributors, with ranks, badges, and "kudos counts". Lithium hosts an annual user conference, LiNC (Lithium Networking Conference) designed to give digital strategists a deeper understanding of trends in social customer engagement. Since its inception in 2008, the event has grown 1,100% to 900+ attendees in 2016. In 2017, the company held a series of localized LiNC events in cities like London, San Francisco, and Sydney.
  • 2.1K
  • 18 Nov 2022
Topic Review
Airway Inflammation in Asthma Pathogenesis
Asthma is a heterogeneous disease characterized by chronic airway inflammation. Group 2 innate lymphoid cells (ILC2) play an important role in the pathogenesis of asthma. ILC2s lack antigen-specific receptors and respond to epithelial-derived cytokines, leading to the induction of airway eosinophilic inflammation in an antigen-independent manner. Additionally, ILC2s might be involved in the mechanism of steroid resistance. Numerous studies in both mice and humans have shown that ILC2s induce airway inflammation through inflammatory signals, including cytokines and other mediators derived from immune or non-immune cells.
  • 2.1K
  • 29 Jun 2023
Topic Review
Modelling of Activated Sludge Process
The activated sludge process (ASP) is the most widely used biological wastewater treatment system. A typical model that would simulate the ASP operation will have the following steps: a model objective, data collection, mathematical equations or models for each ASP as mentioned above, model calibration, and model validation. There are three main types of modelling that have been historically used for the ASP: deterministic or mechanistic modelling, stochastic modelling, and hybrid models combining the two approaches.The most efficient models use hybrid models where stochastic modelling is used for the hard-to-define parameters and variables in the treatment process.
  • 2.1K
  • 10 Jan 2023
Topic Review
Sustainable Supply Chain Practices in the Cement Industry
Sustainable supply chain management (SSCM) is an extension of traditional supply chain management (SCM) that takes into account environmental and social concerns. Cement manufacturing has been recognized as an intensive consumer of natural raw materials, fossil fuels, and energy, as well as a major source of multiple pollutants. This entry attempted to develop a model for SSCM practices by incorporating 23 SSCM factors divided into three dimensions of sustainability: nine factors of environmental SSCM, seven factors of social SSCM, and seven factors of economic SSCM.
  • 2.1K
  • 26 May 2023
Topic Review
Design and Synthesis of Polyphosphodiesters
Polyacids containing –P(O)(OH)– fragment in the polymer backbone, or polyphosphodiesters (PPDEs), hold a special place among natural and synthetic polymers. The structural similarity of PPDEs to natural nucleic and teichoic acids, biocompatibility of PPDEs and their mimicking to biomolecules providing the ‘stealth effect’, high bone mineral affinity of PPDEs, and adjustable hydrolytic stability of PPDEs are the basis for various biomedical, industrial and household applications. Actual synthetic approaches to PPDEs are based on incredibly rich chemistry of organic phosphates and phosphonates, and include modern techniques such as catalytic ring-opening polymerization (ROP), acyclic diene metathesis (ADMET) polycondensation, and others.
  • 2.1K
  • 09 Jan 2023
Topic Review
Eco-safe Rural Roads assessment
Rural roads are important for the communities in the hilly areas of Nepal as they introduce livelihood opportunities at the local level, provide better access to the health care, education and resources. Yet, most of the rural roads in Nepal are unplanned and non-engineered, and these roads are often closed for many months during and after the monsoon. Such roads require huge investments, especially post-monsoon, to clear debris and to keep them operational. In parallel, there is evidence that such roads lead to large number of slope failures and accelerated sedimentation, which degrade the environment and ecosystem services. To remedy such roadside slope failures, eco-engineering practices were tested and demonstrated in partnership with three communities in the Panchase Region of the Nepal’s Central-Western Middle Hills.  Eco-engineering is a hybrid approach, combining civil engineering works for drainage and slope stability, with the plantation of deep-rooted vegetation. It is one activity contributing to Nature based Solutions (NbS) for the sustainable and long-term operation of the rural roads in the Panchase geographic region. This paper describes the inter-disciplinary and community-based research, monitoring and evaluation methods applied, including, the establishment of onsite demonstration plots and Rhizotrons in which Key performance Indicators (KPI) analysis of plant species were performed. The results demonstrated the effectiveness of eco-engineering for reducing risk, while creating ecological co-benefits along rural roads (or eco-safe roads) in hilly areas.  Based on this research, an ‘Eco-safe Rural Road Assessment Framework’ was developed, outlining the systematic process to be followed for the design of eco-safe rural roads for more sustainable road construction and maintenance. The ecological engineering practices which are being promoted by this framework have been accepted by communities and could be further implemented by local government bodies and up-scaled in other similar hilly areas around the country. 
  • 2.1K
  • 30 Oct 2020
Topic Review
Clostridium perfringens as foodborne pathogen
Clostridium perfringens (Cp.) is a Gram-positive, anaerobic, nonmotile rod that forms subterminal spores. This bacterium has characteristics that contribute to its ability to cause foodborne illness by the thermotolerant spores. Meat and poultry products are identified as the main source of infection for humans. The diversity of toxins produced by Cp. has allowed it to be the cause of various diseases in humans and animals, due their rapid growth rate in warm food. In humans, it is associated with diseases related to food consumption that has been prepared or preserved in inadequate hygienic conditions, meanwhile the toxin causes necrotic enteritis in broilers.
  • 2.1K
  • 21 Oct 2020
Topic Review
Bcl-2 Family Evolutionary Conservation
Intrinsic apoptosis, the response to intracellular cell death stimuli, is regulated by the interplay of the B-cell lymphoma 2 (Bcl-2) family and their membrane interactions. Bcl-2 proteins mediate a number of processes including development, homeostasis, autophagy, and innate and adaptive immune responses and their dysregulation underpins a host of diseases including cancer. The Bcl-2 family is characterized by the presence of conserved sequence motifs called Bcl-2 homology (BH) motifs, as well as a transmembrane region, which form the interaction sites and intracellular location mechanism, respectively. Bcl-2 proteins have been recognized in the earliest metazoans including Porifera (sponges), Placozoans, and Cnidarians (e.g., Hydra). A number of viruses have gained Bcl-2 homologs and subvert innate immunity and cellular apoptosis for their replication, but they frequently have very different sequences to their host Bcl-2 analogs. Though most mechanisms of apoptosis initiation converge on activation of caspases that destroy the cell from within, the numerous gene insertions, deletions, and duplications during evolution have led to a divergence in mechanisms of intrinsic apoptosis. Currently, the action of the Bcl-2 family is best understood in vertebrates and nematodes but new insights are emerging from evolutionarily earlier organisms.
  • 2.1K
  • 22 Jun 2021
Topic Review
Machine Learning for Crop Disease
Crop diseases constitute a serious issue in agriculture, affecting both quality and quantity of agriculture production. Disease control has been a research object in many scientific and technologic domains. Technological advances in sensors, data storage, computing resources and artificial intelligence have shown enormous potential to control diseases effectively. A growing body of literature recognizes the importance of using data from different types of sensors and machine learning approaches to build models for detection, prediction, analysis, assessment, etc. However, the increasing number and diversity of research studies requires a literature review for further developments and contributions in this area. 
  • 2.1K
  • 24 Nov 2021
Topic Review
Motor Neuron Disease
Motor neuron disease (MND) is a group of fatal neurodegenerative diseases with no effective treatment, which have the shared characteristic of the progressive loss of upper and/or lower motor neurons. Disease onset is insidious, with patients gradually losing control of their voluntary muscles, resulting in relatively late diagnosis. Due to the nature of the disease and the lack of effective treatment, MND patients usually die within 2 to 3 years following diagnosis, primarily because of the loss of respiratory function. The only drug approved in Australia, Riluzole, only prolongs the median life expectancy by 2 to 3 months. New and effective treatments are therefore urgently needed.
  • 2.1K
  • 20 Sep 2021
Topic Review
Role of Tissue Nonspecific Alkaline Phosphatase beyond Mineralization
Tissue-nonspecific alkaline phosphatase (TNAP) is a key enzyme responsible for skeletal tissue mineralization. It is involved in the dephosphorylation of various physiological substrates, and has vital physiological functions, including extra-skeletal functions, such as neuronal development, detoxification of lipopolysaccharide (LPS), an anti-inflammatory role, bile pH regulation, and the maintenance of the blood brain barrier (BBB). TNAP is also implicated in ectopic pathological calcification of soft tissues, especially the vasculature. Although it is the crucial enzyme in mineralization of skeletal and dental tissues, it is a logical clinical target to attenuate vascular calcification.
  • 2.1K
  • 01 Nov 2021
Topic Review
Biophilic Design Patterns for Primary Schools
Existing frameworks for biophilic design have similar strategies and attributes as useful checklists for designers; however, the focus has been on adults rather than children, and there remains the need for more guidance related to school design by extension. The application of biophilia would be a design resolution in schools because of its impact on children’s health and well-being, which has been more important since the pandemic started; however, it remains quite unexplored in school design in many countries, including the UK. Biophilic design patterns can be used in school buildings and grounds for greater connectivity between spaces and nature in order to promote children’s well-being.
  • 2.1K
  • 03 Dec 2021
Topic Review
Additive Biomanufacturing with Collagen Inks
Collagen is a natural polymer found abundantly in the extracellular matrix (ECM). It is easily extracted from a variety of sources and exhibits excellent biological properties such as biocompatibility and weak antigenicity. Additionally, different processes allow control of physical and chemical properties such as mechanical stiffness, viscosity and biodegradability. Moreover, various additive biomanufacturing technology has enabled layer-by-layer construction of complex structures to support biological function. Additive biomanufacturing has expanded the use of collagen biomaterial in various regenerative medicine and disease modelling application (e.g., skin, bone and cornea). 
  • 2.1K
  • 04 Mar 2022
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