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Topic Review
Hydrothermal Carbonization of Food Waste for Char Production
Managing the increasing volume of food waste worldwide has become a major challenge. In addition, the energy crisis in developing nations of the world is increasing at an alarming rate and the need to proffer solutions is not only expedient but must be of high priority. Hydrothermal carbonization (HTC) refers to a conversion of biomass into an energy-densified or carbon-rich char product. It involves hydrolysis, dehydration, polymerization, and carbonization reactions taking place within moderate temperature (between 180 and 260 °C) and pressure (between 35 and 55 bar) ranges.
  • 2.0K
  • 30 Dec 2022
Topic Review
Requirements and Types of Face Masks
There are different types of face masks (e.g., 3-ply surgical masks, a wide range of fabric masks, single-use face masks, and face shields) and respirators available commercially to protect individuals from getting and/or spreading COVID-19. Face masks are designed to protect primarily from respiratory droplets and particles to some extent. In contrast, the respirators are designed with extended protection against respiratory droplets, particles, and the virus that cause COVID-19. Both face masks and respirators have certain requirements to ensure performance and efficacy at a reliable and consistent level. Mask standards, ratings. National Institute for Occupational Safety and Health (NIOSH), ASTM International, and International Organization for Standardization (formerly known as International Association for Testing Materials) are engaged in creating an open and transparent consensus standards development process for addressing the standards gap identified during the wake of COVID-19 pandemic. The development of standards aimed to define performance requirements for source control, the protective efficacy of face mask or barrier face coverings, and standardized products to inform user selection decisions. The primary purpose of these specifications is to enable source control to protect the mass public with performance requirements such as protection capability, comfort, reusability, and so on. There are a few basic requirements of face masks to be used effectively, including an excellent fit over the nose and mouth of the user to prevent leaking (use of fitter, base, or nose wire) and the use of multi-layer non-woven but breathable fabrics for preventing bright light.
  • 2.0K
  • 25 Apr 2022
Topic Review
Ethylene
Salinity stress is one of the major threats to agricultural productivity across the globe. Research in the past three decades, therefore, has focused on analyzing the effects of salinity stress on the plants. Evidence gathered over the years supports the role of ethylene as a key regulator of salinity stress tolerance in plants. This gaseous plant hormone regulates many vital cellular processes starting from seed germination to photosynthesis for maintaining the plants’ growth and yield under salinity stress. Ethylene modulates salinity stress responses largely via maintaining the homeostasis of Na+/K+, nutrients, and reactive oxygen species (ROS) by inducing antioxidant defense in addition to elevating the assimilation of nitrates and sulfates. Moreover, a cross-talk of ethylene signaling with other phytohormones has also been observed, which collectively regulate the salinity stress responses in plants.
  • 2.0K
  • 09 Jul 2021
Topic Review
Double-Reheat Boiler in China
The ultra-supercritical (USC) double-reheat technology is an immediate area of research focus in China, since the thermal efficiency of USC double-reheat unit is higher than the USC single-reheat unit. The parameters and capacity of USC double-reheat unit in China have made major breakthroughs, and the thermal efficiency of the units are as high as 47–48%, which is the highest in the world. USC double-reheat boiler is one of the most important devices for USC double-reheat unit, and the design concept and precision have a vital effect on the operation of boiler and power station. The most difficult and important factors in the design of double-reheat boiler are the layout of heating surface and the steam temperature regulation method.
  • 2.0K
  • 24 Dec 2021
Topic Review
Hadrosaurid
Hadrosaurids (Greek: ἁδρός, hadrós, "stout, thick"), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The family, which includes ornithopods such as Edmontosaurus and Parasaurolophus, was a common herbivore in the Upper Cretaceous Period of what is now Asia, Europe, Antarctica, South America, and North America. Hadrosaurids are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had a similar body layout. Like the rest of the ornithischians, these animals had a predentary bone and a pubic bone which was positioned backwards in the pelvis. Hadrosaurids are divided into two principal subfamilies: the lambeosaurines (Lambeosaurinae), which had hollow cranial crests or tubes, and the saurolophines, identified as hadrosaurines in most pre-2010 works (Saurolophinae or Hadrosaurinae), which lacked hollow cranial crests (solid crests were present in some forms). Saurolophines tended to be bulkier than lambeosaurines. Lambeosaurines included the aralosaurins, tsintaosaurins, lambeosaurins and parasaurolophins, while saurolophines included the brachylophosaurins, kritosaurins, saurolophins and edmontosaurins. Hadrosaurids were facultative bipeds, with the young of some species walking mostly on two legs and the adults walking mostly on four. Their jaws were evolved for grinding plants, with multiple rows of teeth replacing each other as the teeth wore down.
  • 2.0K
  • 14 Oct 2022
Topic Review
Polymeric Nanoparticles for Drug Delivery
The complexity of some diseases—as well as the inherent toxicity of certain drugs—has led to an increasing interest in the development and optimization of drug-delivery systems. Polymeric nanoparticles stand out as a key tool to improve drug bioavailability or specific delivery at the site of action. The versatility of polymers makes them potentially ideal for fulfilling the requirements of each particular drug-delivery system. In this review, a summary of the state-of-the-art panorama of polymeric nanoparticles as drug-delivery systems has been conducted, focusing mainly on those applications in which the corresponding disease involves an important morbidity, a considerable reduction in the life quality of patients—or even a high mortality. A revision of the use of polymeric nanoparticles for ocular drug delivery, for cancer diagnosis and treatment, as well as nutraceutical delivery, was carried out, and a short discussion about future prospects of these systems is included.
  • 2.0K
  • 27 Jul 2020
Topic Review
Electrostatic Nanoassembly of Novel Composites
Electrostatic assembly is one of the bottom–up approaches used for multiscale composite fabrication. Since its discovery, this method has been actively used in molecular bioscience as well as materials design and fabrication for various applications. Despite the recent advances and controlled assembly reported using electrostatic interaction, the method still possesses vast potentials for various materials design and fabrication. This review article is a timely revisit of the electrostatic assembly method with a brief introduction of the method followed by surveys of recent advances and applications of the composites fabricated. Emphasis is also given to the significant potential of this method for advanced materials and composite fabrication in line with sustainable development goals. Prospective outlook and future developments for micro-/nanocomposite materials fabrication for emerging applications such as energy-related fields and additive manufacturing are also mentioned.
  • 2.0K
  • 11 Nov 2020
Topic Review
Intrinsic and Acquired Chemotherapy Resistance
Drug resistance is a commonly unavoidable consequence of cancer treatment that results in therapy failure and disease relapse. Intrinsic (pre-existing) or acquired resistance mechanisms can be drug-specific or be applicable to multiple drugs, resulting in multidrug resistance.
  • 2.0K
  • 23 Feb 2021
Topic Review
Blockchain-Based Authentication in Internet of Vehicles
Internet of Vehicles (IoV) is capable of providing various intelligent services and supporting different applications for the drivers and passengers on roads. The IoV to be able to offer beneficial road services, huge amounts of data are generated and exchanged among the different communicated entities wirelessly via open channels, which could attract the adversaries and threaten the network with several possible types of security attacks. In this survey, the authentication part of security system is targeted while highlighting the efficiency of blockchains in the IoV environments.
  • 2.0K
  • 10 Dec 2021
Biography
Paul Steinhardt
Paul Joseph Steinhardt (born December 25, 1952) is an American theoretical physicist whose principal research is in cosmology and condensed matter physics. He is currently the Albert Einstein Professor in Science at Princeton University where he is on the faculty of both the Departments of Physics and of Astrophysical Sciences. [1] Steinhardt is best known for his development of new theories of
  • 2.0K
  • 30 Nov 2022
Topic Review
Cycling Education in Europe
Owing to the active promotion of environmentally friendly lifestyles in several European nations, the bicycle is progressively emerging as a predominant mode of transportation on the roadways. This phenomenon can be attributed to a plethora of factors. Numerous cities are gradually prioritizing the development of sustainable transportation systems, which includes restricting car access to central areas. Moreover, there is a growing ecological awareness among individuals who are averse to contributing to urban pollution with vehicle emissions. Additionally, the bicycle offers a means of travel that enables users to maintain and enhance their physical health and overall well-being.
  • 2.0K
  • 11 Oct 2023
Topic Review
Adenosine-to-Inosine RNA Editing
Adenosine-to-inosine RNA editing is a system of post-transcriptional modification widely distributed in metazoans which is catalyzed by ADAR enzymes and occurs mostly in double-stranded RNA (dsRNA) before splicing. This type of RNA editing changes the genetic code, as inosine generally pairs with cytosine in contrast to adenosine, and this expectably modulates RNA splicing.
  • 2.0K
  • 20 May 2022
Topic Review
Landscape Connectivity
Landscape connectivity in ecology is, broadly, "the degree to which the landscape facilitates or impedes movement among resource patches". Alternatively, connectivity may be a continuous property of the landscape and independent of patches and paths. Connectivity includes both structural connectivity (the physical arrangements of disturbance and/or patches) and functional connectivity (the movement of individuals across contours of disturbance and/or among patches). Functional connectivity includes actual connectivity (requires observations of individual movements) and potential connectivity in which movement paths are estimated using the life-history data. The degree to which a landscape is connected determines the amount of dispersal there is among patches, which influences gene flow, local adaptation, extinction risk, colonization probability, and the potential for organisms to move as they cope with climate change.
  • 2.0K
  • 27 Oct 2022
Topic Review Video
K-Center Problem
This entry is adapted from the peer-reviewed paper 10.1109/ACCESS.2019.2933875 K-center problems are particular cases of the facility location problem, where a set of optimal centers are to be found given a set of constraints. In a nutshell, a k-center problem usually seeks a set of at most k centers that minimize the distance a client must travel to its nearest center. Namely, their objective function is often a minmax one. Naturally, these problems are well suited for modeling real location problems. Although many different problems fit within the description of a k-center problem, the most popular of these is the vertex k-center problem, where the input is a simple graph and an integer k, and the goal is to find at most k vertices whose distance to the remaining vertices is minimal.
  • 2.0K
  • 30 Nov 2023
Topic Review
Generating Point Clouds from FMCW Radar
Radar sensing-based devices, particularly those using Frequency-Modulated Continuous Wave (FMCW), can obtain target information such as distance, angle, moving speed, and target size, making them superior when compared to other non-contact sensing technologies. FMCW technology provides access to a lot of crucial information at an affordable price. It is well suited for different working conditions, making it highly suitable for in-vehicle detection scenarios.
  • 2.0K
  • 04 Jan 2024
Topic Review
Batteries vs Hydrogen Storage: Complementary or Substitute
Batteries and hydrogen storage technologies are treated as complementary technologies in some cases, but in other ones they are considered opposed technologies. 
  • 2.0K
  • 20 Sep 2022
Topic Review
A Labile Metallo-Porphyrin as Tool to Control J-Aggregates Chiroptical Properties
The zinc(II) metal derivative of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS4) is quite labile and readily demetallates under acidic conditions, affording the parent diacid porphyrin in a monomeric form. The rate of this process is first order on [ZnTPPS4] and second order on [H+], allowing a precise control of the monomer release in solution. Under high ionic strength, this latter species is able to self-assemble into J-aggregates, whose kinetics of growth are largely modulated by pH. The aggregation kinetics have been treated according to a well-established model, in which the formation of an initial nucleus is the rate determining step preceding the autocatalytic growth of the whole assembly. The extinction spectra of the aggregates suggest the occurrence of a dipolar coupling mechanism very similar to that operating in metal nanoparticles. Spontaneous symmetry breaking takes place in these aggregates as evidenced by unusual circular dichroism spectra. The intensity and sign of the effect is controlled by the aggregation rate and therefore can be tuned through a proper choice of initial conditions.
  • 2.0K
  • 15 Jul 2020
Topic Review
Triple-Negative Breast Cancer and Brain-Metastasis
       A higher propensity of developing brain metastasis exists in triple-negative breast cancer (TNBC). Upon comparing the metastatic patterns of all breast cancer subtypes, patients with TNBC exhibited increased risks of the brain being the initial metastatic site, early brain metastasis development, and shortest brain metastasis-related survival. Notably, the development of brain metastasis differs from that at other sites owing to the brain-unique microvasculature (blood brain barrier (BBB)) and intracerebral microenvironment. Studies of brain metastases from TNBC have revealed the poorest treatment response, mostly because of the relatively backward strategies to target vast disease heterogeneity and poor brain efficacy. Moreover, TNBC is highly associated with the existence of cancer stem cells (CSCs), which contribute to circulating cancer cell survival before BBB extravasation, evasion from immune surveillance, and plasticity in adaptation to the brain-specific microenvironment. We summarized recent literature regarding molecules and pathways and reviewed the effects of CSC biology during the formation of brain metastasis in TNBC.
  • 2.0K
  • 30 Oct 2020
Topic Review
Antimicrobial Peptides in Farm Animals
Antimicrobial peptides (AMPs) are the arsenals of the innate host defense system, exhibiting evolutionarily conserved characteristics that are present in practically all forms of life. Recent years have witnessed the emergence of antibiotic-resistant bacteria compounded with a slow discovery rate for new antibiotics that have necessitated scientific efforts to search for alternatives to antibiotics. Research on the identification of AMPs has generated very encouraging evidence that they curb infectious pathologies and are also useful as novel biologics to function as immunotherapeutic agents. Being innate, they exhibit the least cytotoxicity to the host and exerts a wide spectrum of biological activity including low resistance among microbes and increased wound healing actions. Notably, in veterinary science, the constant practice of massive doses of antibiotics with inappropriate withdrawal programs led to a high risk of livestock-associated antimicrobial resistance. Therefore, the world faces tremendous pressure for designing and devising strategies to mitigate the use of antibiotics in animals and keep it safe for posterity.
  • 2.0K
  • 07 Jan 2021
Topic Review
Green Wireless Sensor Networks
The issue of energy balancing in Wireless Sensor Networks is a pivotal one, crucial in their deployment. This problem can be subdivided in three areas: (i) energy conservation techniques, usually implying minimizing the cost of communication at the nodes since it is known that the radio is the biggest consumer of the available energy; (ii) energy-harvesting techniques, converting energy from not full-time available environmental sources and usually storing it; and (iii) energy transfer techniques, sharing energy resources from one node (either specialized or not) to another one.
  • 2.0K
  • 01 Jul 2021
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