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Topic Review
Ultraviolet Light
Ultraviolet (UV) light is a dry and biologically inert process that decreases the microorganism count by around 99.9% with minimum heating of the packing material. Between the UV lamp and the area to be disinfected, there should be no obstruction. Since dirt absorbs radiation and thereby protects bacteria, the effectiveness of this application is therefore dependent on the sanitation of the material surfaces.
  • 2.8K
  • 10 Aug 2021
Topic Review
Antioxidant Therapy in Oxidative Stress-Induced Neurodegenerative Diseases
Free radicals are formed as a part of normal metabolic activities but are neutralized by the endogenous antioxidants present in cells/tissue, thus maintaining the redox balance. This redox balance is disrupted in certain neuropathophysiological conditions, causing oxidative stress, which is implicated in several progressive neurodegenerative diseases. Following neuronal injury, secondary injury progression is also caused by excessive production of free radicals. Highly reactive free radicals, mainly the reactive oxygen species (ROS) and reactive nitrogen species (RNS), damage the cell membrane, proteins, and DNA, which triggers a self-propagating inflammatory cascade of degenerative events. Dysfunctional mitochondria under oxidative stress conditions are considered a key mediator in progressive neurodegeneration. Exogenous delivery of antioxidants holds promise to alleviate oxidative stress to regain the redox balance.
  • 2.8K
  • 24 Feb 2022
Topic Review
Embryonic Retina Self-Organization In Vivo
Self-organization is a process that ensures histogenesis of the eye retina. The phenomenon of self-organisation is discussed in the spatiotemporal context and illustrated by key findings during vertebrate retina development in vivo and retinal regeneration in amphibians in situ. Described also are histotypic 3D structures obtained from the disaggregated retinal progenitor cells of birds and retinal 3D organoids derived from the mouse and human pluripotent stem cells.
  • 2.8K
  • 30 Jun 2022
Topic Review
Threat (Computer)
In computer security, a threat is a potential negative action or event facilitated by a vulnerability that results in an unwanted impact to a computer system or application. A threat can be either a negative "intentional" event (i.e. hacking: an individual cracker or a criminal organization) or an "accidental" negative event (e.g. the possibility of a computer malfunctioning, or the possibility of a natural disaster event such as an earthquake, a fire, or a tornado) or otherwise a circumstance, capability, action, or event. This is differentiated from a threat actor who is an individual or group that can perform the threat action, such as exploiting a vulnerability to actualise a negative impact. A more comprehensive definition, tied to an Information assurance point of view, can be found in "Federal Information Processing Standards (FIPS) 200, Minimum Security Requirements for Federal Information and Information Systems" by NIST of United States Any circumstance or event with the potential to adversely impact organizational operations (including mission, functions, image, or reputation), organizational assets, or individuals through an information system via unauthorized access, destruction, disclosure, modification of information, and/or denial of service. Also, the potential for a threat-source to successfully exploit a particular information system vulnerability. National Information Assurance Glossary defines threat as: Any circumstance or event with the potential to adversely impact an IS through unauthorized access, destruction, disclosure, modification of data, and/or denial of service. ENISA gives a similar definition: Any circumstance or event with the potential to adversely impact an asset [G.3] through unauthorized access, destruction, disclosure, modification of data, and/or denial of service. The Open Group defines threat as: Anything that is capable of acting in a manner resulting in harm to an asset and/or organization; for example, acts of God (weather, geological events,etc.); malicious actors; errors; failures. Factor analysis of information risk defines threat as: threats are anything (e.g., object, substance, human, etc.) that are capable of acting against an asset in a manner that can result in harm. A tornado is a threat, as is a flood, as is a hacker. The key consideration is that threats apply the force (water, wind, exploit code, etc.) against an asset that can cause a loss event to occur. National Information Assurance Training and Education Center gives a more articulated definition of threat: The means through which the ability or intent of a threat agent to adversely affect an automated system, facility, or operation can be manifest. Categorize and classify threats as follows: Categories Classes Human Intentional Unintentional Environmental Natural Fabricated 2. Any circumstance or event with the potential to cause harm to a system in the form of destruction, disclosure, modification or data, and/or denial of service. 3. Any circumstance or event with the potential to cause harm to the ADP system or activity in the form of destruction, disclosure, and modification of data, or denial of service. A threat is a potential for harm. The presence of a threat does not mean that it will necessarily cause actual harm. Threats exist because of the very existence of the system or activity and not because of any specific weakness. For example, the threat of fire exists at all facilities regardless of the amount of fire protection available. 4. Types of computer systems related adverse events (i. e. , perils) that may result in losses. Examples are flooding, sabotage and fraud. 5. An assertion primarily concerning entities of the external environment (agents); we say that an agent (or class of agents) poses a threat to one or more assets; we write: T(e;i) where: e is an external entity; i is an internal entity or an empty set. 6. An undesirable occurrence that might be anticipated but is not the result of a conscious act or decision. In threat analysis, a threat is defined as an ordered pair, <peril; asset category>, suggesting the nature of these occurrences but not the details (details are specific to events). 7. The potential violation of security. 8. A set of properties of a specific external entity (which may be either an individual or class of entities) that, in union with a set of properties of a specific internal entity, implies a risk (according to a body of knowledge).
  • 2.8K
  • 02 Nov 2022
Topic Review
Indefinite Lifespan
Indefinite lifespan (also known as indefinite life extension or bio-indefinite) is a term used in the life extension movement and transhumanism to refer to the hypothetical longevity of humans (and other life-forms) under conditions in which ageing is effectively and completely prevented and treated. Their lifespans would be "indefinite" (that is, they would not be "immortal"), because protection from the effects of aging on health does not guarantee survival. Such individuals would still be susceptible to death by disease, starvation, accidents, or deliberate killing, but not death from aging. Semantically, "indefinite lifespan" is more accurate than "immortality" which, especially in religious contexts, implies an inability to die.
  • 2.8K
  • 26 Oct 2022
Topic Review
Deep Packet Inspection
Deep packet inspection (DPI) is a type of data processing that inspects in detail the data being sent over a computer network, and may take actions such as alerting, blocking, re-routing, or logging it accordingly. Deep packet inspection is often used to baseline application behavior, analyze network usage, troubleshoot network performance, ensure that data is in the correct format, check for malicious code, eavesdropping, and internet censorship, among other purposes. There are multiple headers for IP packets; network equipment only needs to use the first of these (the IP header) for normal operation, but use of the second header (such as TCP or UDP) is normally considered to be shallow packet inspection (usually called stateful packet inspection) despite this definition. There are multiple ways to acquire packets for deep packet inspection. Using port mirroring (sometimes called Span Port) is a very common way, as well physically inserting a network tap which duplicates and sends the data stream to an analyzer tool for inspection. Deep Packet Inspection (and filtering) enables advanced network management, user service, and security functions as well as internet data mining, eavesdropping, and internet censorship. Although DPI has been used for Internet management for many years, some advocates of net neutrality fear that the technique may be used anticompetitively or to reduce the openness of the Internet. DPI is used in a wide range of applications, at the so-called "enterprise" level (corporations and larger institutions), in telecommunications service providers, and in governments.
  • 2.8K
  • 09 Nov 2022
Topic Review Peer Reviewed
Kidney Issues Associated with COVID-19 Disease
Infection with SARS-CoV-2 and the resulting COVID-19 can cause both lung and kidney damage. SARS-CoV-2 can directly infect renal cells expressing ACE2 receptors, resulting in kidney damage, and acute kidney injury (AKI) has been reported in COVID-19 hospitalized patients. The pathophysiology of COVID-19-associated AKI is multifactorial. Local and systemic inflammation, immune system dysregulation, blood coagulation disorders, and activation of the renin-angiotensin-aldosterone system (RAAS) are factors that contribute to the development of AKI in COVID 19 disease. COVID-19 patients with kidney involvement have a poor prognosis, and patients with chronic kidney disease (CKD) infected with SARS-CoV-2 have an increased mortality risk. CKD patients with COVID-19 may develop end-stage renal disease (ESRD) requiring dialysis. In particular, patients infected with SARS-CoV-2 and requiring dialysis, as well as patients who have undergone kidney transplantation, have an increased risk of mortality and require special consideration. Nephrologists and infectious disease specialists face several clinical dilemmas in the prophylaxis and treatment of CKD patients with COVID-19. This entry presents recent data showing the effects of COVID-19 on the kidneys and CKD patients and the challenges in the management of CKD patients with COVID-19, and discusses treatment strategies for these patients.
  • 2.8K
  • 05 Sep 2023
Topic Review
Impact of Drought in Plant-Metabolism
       Plants are often exposed to unfavorable environmental conditions, for instance abiotic stresses, which dramatically alter distribution of plant species among ecological niches and limit the yields of crop species. Among these, drought stress is one of the most impacting factors which alter seriously the plant physiology, finally leading to the decline of the crop productivity. Drought stress causes in plants a set of morpho-anatomical, physiological and biochemical changes, mainly addressed to limit the loss of water by transpiration with the attempt to increase the plant water use efficiency. The stomata closure, one of the first consistent reactions observed under drought, results in a series of consequent physiological/biochemical adjustments aimed at balancing the photosynthetic process as well as at enhancing the plant defense barriers against drought-promoted stress (e.g., stimulation of antioxidant systems, accumulation of osmolytes and stimulation of aquaporin synthesis), all representing an attempt by the plant to overcome the unfavorable period of limited water availability. In view of the severe changes in water availability imposed by climate change factors and considering the increasing human population, it is therefore of outmost importance to highlight: (i) how plants react to drought; (ii) the mechanisms of tolerance exhibited by some species/cultivars; and (iii) the techniques aimed at increasing the tolerance of crop species against limited water availability. All these aspects are necessary to respond to the continuously increasing demand for food, which unfortunately parallels the loss of arable land due to changes in rainfall dynamics and prolonged period of drought provoked by climate change factors. This review summarizes the most updated findings on the impact of drought stress on plant morphological, biochemical and physiological features and highlights plant mechanisms of tolerance which could be exploited to increase the plant capability to survive under limited water availability. In addition, possible applicative strategies to help the plant in counteracting unfavorable drought periods are also discussed.
  • 2.8K
  • 24 Aug 2020
Topic Review
Severe TBI: Second and Third Tier Therapies
Intracranial hypertension is a common finding in severe traumatic brain injury, and requires treatment in the intensive care unit with intracranial pressure monitoring and, when possible, the application of multimodal neuromonitoring. A three-tier approach is suggested in current rec-ommendations, with higher tier therapies having more significant side effects. Researchers explain the rationale for this approach, they analyze the benefits and risks of each therapeutic mo-dality, and they discuss how to adapt the therapy to the resources available, based on the most recent recommendations.
  • 2.8K
  • 08 Oct 2022
Topic Review
Orphan Train
The Orphan Train Movement was a supervised welfare program that transported orphaned and homeless children from crowded Eastern cities of the United States to foster homes located largely in rural areas of the Midwest. The orphan trains operated between 1854 and 1929, relocating about 200,000 orphaned, abandoned, or homeless children. Three charitable institutions, Children's billage (founded 1851 by 24 philanthropists), the Children's Aid Society (established 1853 by Charles Loring Brace) and later, the New York Foundling Hospital, endeavored to help these children. The institutions were supported by wealthy donors and operated by professional staff. The two institutions developed a program that placed homeless, orphaned, and abandoned city children, who numbered an estimated 30,000 in New York City alone in the 1850s, in foster homes throughout the country. The children were transported to their new homes on trains that were labeled "orphan trains" or "baby trains". This relocation of children ended in the 1920s with the beginning of organized foster care in America.
  • 2.8K
  • 28 Nov 2022
Topic Review
Hydroxytyrosol and Oleuropein in Aging and Related Disorders
Aging is a multi-faceted process caused by the accumulation of cellular damage over time, associated with a gradual reduction of physiological activities in cells and organs. This degeneration results in a reduced ability to adapt to homeostasis perturbations and an increased incidence of illnesses such as cognitive decline, neurodegenerative and cardiovascular diseases, cancer, diabetes, and skeletal muscle pathologies. Key features of aging include a chronic low-grade inflammation state and a decrease of the autophagic process. The Mediterranean diet has been associated with longevity and ability to counteract the onset of age-related disorders. Extra virgin olive oil, a fundamental component of this diet, contains bioactive polyphenolic compounds as hydroxytyrosol (HTyr) and oleuropein (OLE), known for their antioxidant, anti-inflammatory, and neuroprotective properties.
  • 2.8K
  • 24 Apr 2023
Topic Review
Types of Artificial Neural Networks
The well-known artificial neural networks (ANNs) are nearly as old as Artificial Intelligence, and they represent a tool, or a model, rather than a method by which to implement AI in autonomous systems. The growing interest in Artificial Intelligence is pervading several domains of technology and robotics research. Only recently has the space community started to investigate deep learning methods and artificial neural networks for space systems. The applications of artificial neural networks to system identification, control synthesis and optical navigation are reviewed and compared using quantitative and qualitative metrics. 
  • 2.8K
  • 27 Sep 2022
Topic Review
Unmanned Aerial Vehicle Computing Platforms
Unprecedented advances in Unmanned Aerial Vehicles (UAVs) or drones, their application has become widespread in public and industrial sectors. Now, drones are used in many areas such as the deployment of wireless networks, product shipping and delivery, precision agriculture, object detection and tracking, border surveillance and monitoring, remote sensing and environmental monitoring, traffic control, and earth mapping.
  • 2.8K
  • 31 Oct 2022
Topic Review
IBM Db2 Family
Db2 is a family of data management products, including database servers, developed by IBM. They initially supported the relational model, but were extended to support object–relational features and non-relational structures like JSON and XML. The brand name was originally styled as DB/2, then DB2 until 2017 and finally changed to its present form.
  • 2.8K
  • 01 Nov 2022
Topic Review
Conducting Poly(Methyl Methacrylate) (PMMA)
Poly(methyl methacrylate), PMMA is a lightweight insulating material that is known for its high Young's Modulus and good optical transmittance properties. Benefiting from these properties, there are recently vast interests to produce conducting PMMA for various applications including electronics, corrosion protective coatings,  diodes, sensors, and many more. Conducting PMMA is possible to produce by incorporating conducting polymers such as  polyaniline (PANi) by physical blending method or by co-polymerization technique. PANi has been the main choice to incorporate with PMMA due to its good conductivity, better environmental stability, and good redox reversibility. In addition, the limitations of PANi include poor adhesion, low mechanical stability and, limited solubility in most organic solvents can be surpassed by blending or co-polymerizing with thermoplastics such as PMMA.
  • 2.8K
  • 30 Jun 2021
Topic Review
New Frontiers in Cancer Therapy and Diagnostics
Cancer remains one of the most pressing challenges in modern medicine, but recent advancements are revolutionizing both therapeutic and diagnostic landscapes. This exploration of new frontiers in cancer therapy and diagnostics highlights a diverse array of innovative strategies that target the molecular mechanisms of tumorigenesis while enhancing early detection and personalized care. Cutting-edge therapies, such as small-molecule inhibitors and monoclonal antibodies, specifically target oncogene-driven pathways, offering selective toxicity over traditional chemotherapy. Immunotherapies, including immune checkpoint inhibitors, radioimmunotherapy, antibody-drug conjugates (ADCs), and chimeric antigen receptor (CAR) T-cell therapy, activate the immune system to combat malignancies, showing remarkable efficacy in oncogene-addicted cancers and hematological malignancies. Emerging approaches like cancer vaccines and oncolytic viruses further amplify immune responses, while liquid biopsy transforms diagnostics by analyzing circulating tumor markers for early detection, treatment monitoring, and resistance profiling. Artificial intelligence (AI) and machine learning amplify these advances, refining diagnosis through image analysis, predicting oncogenic mutations, and guiding personalized treatment plans. Together, these breakthroughs—including targeted therapies, immunotherapies, and technology-driven diagnostics—represent a major progress in oncology, though challenges like drug resistance, tumor heterogeneity, and accessibility persist. This summary highlights the promise and complexity of these new frontiers, paving the way for more effective, tailored cancer management.
  • 2.8K
  • 21 Mar 2025
Topic Review
Beneficial health properties of common natural phenolic acids
Phenolic acids comprise a group of natural compounds that are present in a wide range of herbs and other species of the plant kingdom. This work focuses on the most common natural occurring phenolic acids (caffeic, carnosic, ferulic, gallic, p-coumaric, rosmarinic, vanillic) and gives a summary of their recently reported health related effects that mainly link to their antioxidant properties. A number of in vitro and in vivo animal studies has been screened by the authors who report on most important research findings on each individual phenolic acid (or natural mixtures of them) while also formulating a number of conclusions and recommendations for future work in this scientific field.
  • 2.8K
  • 24 Oct 2020
Topic Review Peer Reviewed
Life Satisfaction and Its Relation to Leisure and Self-Reported Health with an Example from Mexico
Life satisfaction is a concept related to an individual’s evaluation of their life, which is determined by taking into account all of the aspects that could affect it. Such an evaluation usually takes into consideration more than just economic conditions. In this paper, we present the relationship of life satisfaction with two of its main determinants, namely, self-reported health and leisure satisfaction. To exemplify this relationship, we utilize data from Mexico.
  • 2.8K
  • 02 Dec 2024
Topic Review
Bioethanol for Cooking
Bioethanol has been identified by the academic literature and in the development community as a promising clean fuel to replace charcoal. Bioethanol is one of the cooking fuels considered to be clean based on the 2014 WHO guidelines, which aim to reduce the health risks associated with exposure to indoor air pollution from household fuel combustion. 
  • 2.8K
  • 19 Oct 2023
Topic Review
The New Palgrave Dictionary of Economics
The New Palgrave Dictionary of Economics (2008), 2nd ed., is an eight-volume reference work on economics, edited by Steven N. Durlauf and Lawrence E. Blume and published by Palgrave Macmillan. It runs to 7,680 pages and 5.8 million words. It includes 1,844 articles, of which 1057 are new articles and, from the earlier edition, 80 "classic" essays, 157 revised articles, and 550 edited articles. It is the product of 1,506 contributors, 25 of them Nobel Laureates in Economics. Articles are classified according to Journal of Economic Literature (JEL) classification codes. The New Palgrave is also available in a hyperlinked online version. Article information by abstract, outline, and keywords is available without subscription. These are accessed by "Go to" or "Quick" searches or alphabetical article links by first letter, see Articles A-Z. Refined search by using JEL classification code, article elements, Boolean operators, or wildcards is available, see Advanced search. Online content is added to the 2008 edition from quarterly updates links, see Online Updates. The first edition was titled The New Palgrave: A Dictionary of Economics (1987), edited by John Eatwell, Murray Milgate, and Peter Newman and published in four volumes. It is discussed in a section below. Access to full-text articles for both editions and post-2008 updates is available online by subscription, whether of an organization, a person, or a person through an organization.
  • 2.8K
  • 29 Nov 2022
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