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Topic Review
Bidens pilosa (Asteraceae)
Bidens pilosa (Asteraceae) is an easy-to-grow medicinal herb which is also consumed as a leafy vegetable. This plant has been shown to have various health benefits and treatment of disease/conditions such as malaria,  hypertension, obesity and typhoid. Interestingly, some secondary metabolites such as hydroxycinnamic acid derivatives that have been identified in B. pilosa have been shown to have various bioactivities health such as anti-cancer properties, HIV-integrase inhibition and anti-diabetic properties. In this study, exogenous treatment of B. pilosa leaves with two signal molecules (MeJA and MeSA) induced metabolic changes, differentially perturbating the accumulation of these biologically important metabolites. Moreover, the perturbation of isomeric molecules, especially the cis geometrical isomers of HCA derivatives by both treatments, further point to the biological significance of these molecules during physiological responses to stress. The results highlight the possibility of using phytohormones to enhance the accumulation of bioactive secondary metabolites in this plant.
  • 1.8K
  • 06 Nov 2020
Topic Review
Antiviral Drugs against COVID-19
Several FDA-approved available antiviral drugs, alone or in combination, have been screened clinically for their extended use since the early phase of the current pandemic to find a safe and effective treatment option against COVID-19, and many clinical trials of these antiviral drugs are still ongoing. However, an in-depth understanding is required from current clinical literature reports to execute integrated approaches between computational and experimental methods to guarantee high success rates of repositioned drugs. Moreover, multiple challenges associated with repurposed drugs have been identified, including dose adjustments, route of administration, acute/chronic toxicity, appropriate delivery systems, etc..
  • 1.8K
  • 27 Sep 2021
Topic Review
Conversion of 5-hydroxymethylfurfural to 2,5-dimethylfuran
Many researchers have extensively explored selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF), and some of them were able to achieve high conversion and a high yield of DMF under certain reaction conditions. However, the main challenge is to reduce the operational cost using cost-effective catalysts as an alternative to the expensive noble metals. Overall, the approach of using bifunctional catalysts is an important direction for catalysis in general and particularly for reactions that require significantly different types of elementary steps as part of an overall reaction. For this reason, efforts to use the rational design of interfaces will become important for supplementing the promising initial work in demonstrating bifunctional catalysis for catalytic transformations of biomass-derived 5-hydroxymethylfurfural to a potential liquid fuel, 2,5-dimethylfuran. Apart from the different types of metal and support, it was also observed that reaction conditions, namely the type of solvent, H2 donor, reaction temperature, reaction time, and H2. 
  • 1.8K
  • 28 Jun 2022
Topic Review
Role of Retinal Pigment Epithelium
The retinal pigment epithelium (RPE), situated upon Bruch’s membrane, plays multiple roles in the ocular system by interacting with photoreceptors and. Therefore, dysfunction of the RPE causes diseases related to vision loss, such as age-related macular degeneration (AMD). 
  • 1.8K
  • 24 Nov 2021
Topic Review
Converse (Logic)
In logic and mathematics, the converse of a categorical or implicational statement is the result of reversing its two constituent statements. For the implication P → Q, the converse is Q → P. For the categorical proposition All S are P, the converse is All P are S. Either way, the truth of the converse is generally independent from that of the original statement.
  • 1.8K
  • 27 Oct 2022
Topic Review
Approaches for Flow-Shop Scheduling Problems
Flow-shop scheduling problems are classic examples of multi-resource and multi-operation scheduling problems where the objective is to minimize the makespan. Because of the high complexity and intractability of the problem, apart from some exceptional cases, there are no explicit algorithms for finding the optimal permutation in multi-machine environments. 
  • 1.8K
  • 13 Sep 2023
Topic Review
The History of Blood Vessel Anastomosis
Surgical technique and technology frequently coevolve. The brief history of blood vessel anastomosis is full of famous names. While the techniques pioneered by these surgeons have been well described, the technology that facilitated their advancements and their inventors deserve recognition. The mass production of laboratory microscopes in the mid-1800s allowed for an explosion of interest in tissue histology. This improved understanding of vascular physiology and thrombosis laid the groundwork for Carrel and Guthrie to report some of the first successful vascular anastomoses. In 1916, McLean discovered heparin. Twenty-four years later, Gordon Murray found that it could prevent thrombosis when performing end-to-end anastomosis. These discoveries paved the way for the first-in-human kidney transplantations. Otolaryngologists Nylen and Holmgren were the first to bring the laboratory microscope into the operating room, but Jacobson was the first to apply these techniques to microvascular anastomosis. His first successful attempt in 1960 and the subsequent development of microsurgical tools allowed for an explosion of interest in microsurgery, and several decades of innovation followed.
  • 1.8K
  • 15 Mar 2022
Topic Review
Avascular Necrosis of Femoral Head
Avascular necrosis (AVN) of the femoral head is caused by disruption of the blood supply to the proximal femur. The alterations in the blood supply may occur following a traumatic event or result from a non-traumatic cause. Femoral neck fracture and hip dislocation and associated surgical procedures, corticosteroid therapy, and alcohol abuse frequently lead to AVN development. 
  • 1.8K
  • 29 Jun 2022
Topic Review
Casein Kinase 1α
Wnt signaling regulates numerous cellular processes during embryonic development and adult tissue homeostasis. Underscoring this physiological importance, deregulation of the Wnt signaling pathway is associated with many disease states, including cancer. Here, we review pivotal regulatory events in the Wnt signaling pathway that drive cancer growth. We then discuss the roles of the established negative Wnt regulator, casein kinase 1α (CK1α), in Wnt signaling. Although the study of CK1α has been ongoing for several decades, the bulk of such research has focused on how it phosphorylates and regulates its various substrates. We focus here on what is known about the mechanisms controlling CK1α, including its putative regulatory proteins and alternative splicing variants. Finally, we describe the discovery and validation of a family of pharmacological CK1α activators capable of inhibiting Wnt pathway activity. One of the important advantages of CK1α activators, relative to other classes of Wnt inhibitors, is their reduced on-target toxicity, overcoming one of the major impediments to developing a clinically relevant Wnt inhibitor. Therefore, we also discuss mechanisms that regulate CK1α steady-state homeostasis, which may contribute to the deregulation of Wnt pathway activity in cancer and underlie the enhanced therapeutic index of CK1α activators. 
  • 1.8K
  • 26 Oct 2020
Topic Review
Screen-Printed Electrodes as Transducers
In the last decades, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as low-cost, disposability, ease of use and portability, which allow fast analysis in point-of-need scenarios. The main characteristics of SPEs as electrochemical transducers for biosensors are described below.
  • 1.8K
  • 13 Apr 2021
Topic Review
Enantioselective Catalytic C-H Amidations
The crucial role played by compounds bearing amide functions, not only in biological processes but also in several fields of chemistry, life polymers and material sciences, has brought about many significant discoveries and innovative approaches for their chemical synthesis. Within this context, and following the development of C-H functionalization strategies, C-H amidation reactions have only recently emerged as valuable approaches for the construction of amide functions. These methodologies have been successfully used for both C(sp2)- and C(sp3)-H activations and blossoming synthetic applications have appeared in the last two years (2019-2020 timeframe).
  • 1.8K
  • 15 Apr 2021
Topic Review
5-Hydroxytryptamine Receptors
5-Hydroxytryptamine (5-HT) receptors, also referred to as serotonin receptors, are a monoamine receptor molecule, activated by the neurotransmitter serotonin.
  • 1.8K
  • 30 Dec 2021
Topic Review
Motivated Forgetting
Motivated forgetting is a theorized psychological behavior in which people may forget unwanted memories, either consciously or unconsciously. It is an example of defence mechanism, since these are unconscious or conscious coping techniques used to reduce anxiety arising from unacceptable or potentially harmful impulses thus it can be a defence mechanism in some ways. Defence mechanisms are not to be confused with conscious coping strategies. Thought suppression is a method in which people protect themselves by blocking the recall of these anxiety-arousing memories. For example, if something reminds a person of an unpleasant event, their mind may steer towards unrelated topics. This could induce forgetting without being generated by an intention to forget, making it a motivated action. There are two main classes of motivated forgetting: psychological repression is an unconscious act, while thought suppression is a conscious form of excluding thoughts and memories from awareness.
  • 1.8K
  • 26 Oct 2022
Topic Review
Evil God Challenge
The Evil God Challenge is a thought experiment. The challenge is to explain why an all-good god should be more likely than an all-evil god. Those who advance this challenge assert that, unless there is a satisfactory answer to the challenge, there is no reason to accept God is good or can provide moral guidance.
  • 1.8K
  • 27 Oct 2022
Topic Review
Impact of Artificial Intelligence on the Job Market
This research explores the impact of artificial intelligence (AI) on the job market, including both its potential benefits and drawbacks. The research discusses how AI can automate repetitive tasks, improve accuracy, and assist workers in performing their jobs more effectively. However, the article also highlights concerns about job displacement, biases and discrimination, and the deskilling of workers. The research examines the impact of AI on different industries and types of jobs and discusses the need for workers to develop complementary skills and for employers to invest in AI technologies that work collaboratively with human workers. The research concludes by highlighting the importance of investing in education and training programs, ensuring ethical and transparent development and deployment of AI, and implementing appropriate policies to support workers who are displaced by AI.
  • 1.8K
  • 22 May 2023
Topic Review
Anomaly
In quantum physics an anomaly or quantum anomaly is the failure of a symmetry of a theory's classical action to be a symmetry of any regularization of the full quantum theory. In classical physics, a classical anomaly is the failure of a symmetry to be restored in the limit in which the symmetry-breaking parameter goes to zero. Perhaps the first known anomaly was the dissipative anomaly in turbulence: time-reversibility remains broken (and energy dissipation rate finite) at the limit of vanishing viscosity. In quantum theory, the first anomaly discovered was the Adler–Bell–Jackiw anomaly, wherein the axial vector current is conserved as a classical symmetry of electrodynamics, but is broken by the quantized theory. The relationship of this anomaly to the Atiyah–Singer index theorem was one of the celebrated achievements of the theory. Technically, an anomalous symmetry in a quantum theory is a symmetry of the action, but not of the measure, and so not of the partition function as a whole.
  • 1.8K
  • 04 Nov 2022
Topic Review
PhyloCode
The International Code of Phylogenetic Nomenclature, known as the PhyloCode for short, is a developing draft for a formal set of rules governing phylogenetic nomenclature. Its current version is specifically designed to regulate the naming of clades, leaving the governance of species names up to the rank-based Nomenclature codes (ICN, ICZN, ICNB, ICTV). The PhyloCode is associated with the International Society for Phylogenetic Nomenclature (ISPN). The PhyloCode proposes to regulate phylogenetic nomenclature by providing rules for how to decide which associations of names and definitions will be considered established, which of those will be considered homonyms or synonyms, and which one of a set of synonyms or homonyms will be considered accepted (generally the one registered first; see below). The PhyloCode will only allow the naming of clades, not of paraphyletic or polyphyletic groups, and will only allow the use of specimens, species, and apomorphies as specifiers (anchors).
  • 1.8K
  • 06 Oct 2022
Topic Review
AAZTA-Derived Chelators as Innovative Radiopharmaceuticals
The chelating agent AAZTA features a mesocyclic seven-membered diazepane ring, conferring some of the properties of both acyclic and macrocyclic chelating agents. Described in the early 2000s, AAZTA and its derivatives exhibited interesting properties once complexed with metals and radiometals, combining a fast kinetic of formation with a slow kinetic of dissociation. Importantly, the extremely short coordination reaction times allowed by AAZTA derivatives were particularly suitable for short half-life radioelements (i.e., 68Ga).
  • 1.8K
  • 28 Feb 2022
Topic Review
Alignment-Free Approaches
Alignment-free (AF) methodologies have increased in popularity in the last decades as alternative tools to alignment-based (AB) algorithms for performing comparative sequence analyses. They have been especially useful to detect remote homologs within the twilight zone of highly diverse gene/protein families and superfamilies. The most popular alignment-free methodologies, as well as their applications to classification problems, have been described in previous reviews. Despite a new set of graph theory-derived sequence/structural descriptors that have been gaining relevance in the detection of remote homology, they have been omitted as AF predictors when the topic is addressed. Here, we first go over the most popular AF approaches used for detecting homology signals within the twilight zone and then bring out the state-of-the-art tools encoding graph theory-derived sequence/structure descriptors and their success for identifying remote homologs.
  • 1.8K
  • 29 Oct 2020
Topic Review
Aerial LiDAR Data Augmentation
Direct point-cloud visualisation is a common approach for visualising large datasets of aerial terrain LiDAR scans. However, because of the limitations of the acquisition technique, such visualisations often lack the desired visual appeal and quality, mostly because certain types of objects are incomplete or entirely missing (e.g., missing water surfaces, missing building walls and missing parts of the terrain). To improve the quality of direct LiDAR point-cloud rendering, we present a point-cloud processing pipeline that uses data fusion to augment the data with additional points on water surfaces, building walls and terrain through the use of vector maps of water surfaces and building outlines. In the last step of the pipeline, we also add colour information, and calculate point normals for illumination of individual points to make the final visualisation more visually appealing. We evaluate our approach on several parts of the Slovenian LiDAR dataset.
  • 1.8K
  • 04 Jun 2021
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