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Topic Review
Photodynamic Therapy for Deep-Seated Tumors
Photodynamic therapy (PDT) works through the photoactivation of a specific photosensitizer (PS) in a tumor in the presence of oxygen. PDT is widely applied in oncology to treat various cancers as it has a minimally invasive procedure and high selectivity, does not interfere with other treatments, and can be repeated as needed. A large amount of reactive oxygen species (ROS) and singlet oxygen is generated in a cancer cell during PDT, which destroys the tumor effectively. However, the efficacy of PDT in treating a deep-seated tumor is limited due to three main reasons: Limited light penetration depth, the low oxygen concentration in the hypoxic core, and poor PS accumulation inside a tumor. Thus, PDT treatments are only approved for superficial and thin tumors. With the advancement of nanotechnology, PDT to treat deep-seated or thick tumors is becoming a reachable goal. In this review, we provide an update on the strategies for improving PDT with nanomedicine using different sophisticated-design nanoparticles, including two-photon excitation, X-ray activation, targeting tumor cells with surface modification, alteration of tumor cell metabolism pathways, the release of therapeutic gases, improvement of tumor hypoxia, and stimulation of host immunity.
  • 1.8K
  • 11 Oct 2021
Topic Review
Hajdu–Cheney Syndrome
Hajdu–Cheney syndrome (HCS) is a rare genetic disease that causes acroosteolysis and generalized osteoporosis, accompanied by a series of developmental skeletal disorders and multiple clinical and radiological manifestations. It has an autosomal dominant inheritance, although there are several sporadic non-hereditary cases.
  • 1.8K
  • 09 Sep 2020
Topic Review
Silicon Multi-Mode Routing Devices
The multi-mode routing devices are used for transferring higher-order modes in the multi-mode bus waveguide without introducing mode-dependent losses or inter-modal crosstalk, including multi-mode bend, multi-mode crossing and multi-mode splitter.
  • 1.8K
  • 29 Sep 2020
Topic Review
Neurofibromatosis Type 1 and Brain
Neurofibromatosis type 1 (NF1), the most frequent phakomatosis and one of the most common inherited tumor predisposition syndromes, is characterized by several manifestations that pervasively involve central and peripheral nervous system structures. 
  • 1.8K
  • 20 Apr 2021
Topic Review
Microvascular Tissue Engineering
Tissue engineering and regenerative medicine have come a long way in recent decades, but the lack of functioning vasculature is still a major obstacle preventing the development of thicker, physiologically relevant tissue constructs. A large part of this obstacle lies in the development of the vessels on a microscale—the microvasculature—that are crucial for oxygen and nutrient delivery. 
  • 1.8K
  • 23 Jun 2021
Topic Review
Dietary Polyphenols' Biopharmaceutical Classification System
Polyphenols are natural organic compounds produced by plants, acting as antioxidants by reacting with ROS. These compounds are widely consumed in daily diet and many studies report several benefits to human health thanks to their bioavailability in humans. However, the digestion process of phenolic compounds is still not completely clear. Moreover, bioavailability is dependent on the metabolic phase of these compounds. The LogP value can be managed as a simplified measure of the lipophilicity of a substance ingested within the human body, which affects resultant absorption. The biopharmaceutical classification system (BCS), a method used to classify drugs intended for gastrointestinal absorption, correlates the solubility and permeability of the drug with both the rate and extent of oral absorption. BCS may be helpful to measure the bioactive constituents of foods, such as polyphenols, in order to understand their nutraceutical potential. There are many literature studies that focus on permeability, absorption, and bioavailability of polyphenols and their resultant metabolic byproducts, but there is still confusion about their respective LogP values and BCS classification. 
  • 1.8K
  • 17 Jun 2021
Topic Review
Big data sustainable supply chains
Sustainable supply chain management (SSCM) has received much attention in the decade ending in 2020 due to an increased awareness of climate change and environmental and social issues across the globe. SSCM requires firms across a supply chain to report not only on profits but also on environmental and social performance. SSCM can be improved by utilizing big data analytics, as such, the paper investigated how big data analytics can be used to enhance SSCM practices in manufacturing supply chains
  • 1.8K
  • 19 Jul 2021
Topic Review
Laser-Induced Graphene Based Flexible Electronic Devices
Since it was reported in 2014, laser-induced graphene (LIG) has received growing attention for its fast speed, non-mask, and low-cost customizable preparation, and has shown its potential in the fields of wearable electronics and biological sensors that require high flexibility and versatility. The achievements of LIG based devices for detecting diverse bio-signal, serving as monitoring human motions, energy storage, and heaters are highlighted here, referring to the advantages of LIG in flexible designability, excellent electrical conductivity, and diverse choice of substrates.
  • 1.8K
  • 09 Feb 2022
Topic Review
Insect Rearing Techniques for Biological Control Programs
It is important to rear insects, whether on a small scale for research or a large scale for mass rearing, for use in biological control (BC) programs with macro-organisms.
  • 1.8K
  • 14 Feb 2022
Topic Review
Combating Biofilms Using Antimicrobial Agents and Therapeutic Approaches
Biofilms are intricate bacterial assemblages that attach to diverse surfaces using an extracellular polymeric substance that protects them from the host immune system and conventional antibiotics. Biofilms cause chronic infections that result in millions of deaths around the world every year. Since the antibiotic tolerance mechanism in biofilm is different than that of the planktonic cells due to its multicellular structure, the currently available antibiotics are inadequate to treat biofilm-associated infections which have led to an immense need to find newer treatment options. Over the years, various novel antibiofilm compounds able to fight biofilms have been discovered. 
  • 1.8K
  • 29 Mar 2022
Topic Review
Factor V Leiden
Factor V Leiden (rs6025 or F5 p.R506Q) is a variant (mutated form) of human factor V (one of several substances that helps blood clot), which causes an increase in blood clotting (hypercoagulability). Due to this mutation, protein C, an anticoagulant protein that normally inhibits the pro-clotting activity of factor V, is not able to bind normally to factor V, leading to a hypercoagulable state, i.e., an increased tendency for the patient to form abnormal and potentially harmful blood clots. Factor V Leiden is the most common hereditary hypercoagulability (prone to clotting) disorder amongst ethnic Europeans. It is named after the Dutch city of Leiden, where it was first identified in 1994 by Rogier Maria Bertina under the direction of (and in the laboratory of) Pieter Hendrick Reitsma. Despite the increased risk of venous thromboembolisms, people with one copy of this gene have not been found to have shorter lives than the general population.
  • 1.8K
  • 07 Nov 2022
Topic Review
Biological Activity of Cobalt Nanomaterials against Infectious Diseases
Infectious diseases remain the most serious public health issue, which requires the development of more effective strategies for infectious control. As a kind of ultra-trace element, cobalt is essential to the metabolism of different organisms. Nanotechnology has attracted increasing attention worldwide due to its wide application in different areas, including medicine. Based on the important biological roles of cobalt, cobalt nanomaterials have recently been widely developed for their attractive biomedical applications. With advantages such as low costs in preparation, hypotoxicity, photothermal conversion abilities, and high drug loading ability, cobalt nanomaterials have been proven to show promising potential in anticancer and anti-infection treatment.
  • 1.8K
  • 15 Nov 2022
Topic Review
Electroless Nickel Plating
Electroless nickel (EN) plating is an auto-catalytic reaction that deposits an even layer of nickel-phosphorus or nickel-boron alloy on the surface of a solid material, or substrate, like metal or plastic. The process involves dipping the substrate in a bath of plating solution, where a reducing agent, like hydrated sodium hypophosphite (NaPO2H2 · H2O), reacts with the material's ions to deposit the nickel alloy. The metallurgical properties of the alloy depend on the percentage of phosphorus, which can range from 2–5% (low phosphorus) to 11–14% (high phosphorus). Unlike electroplating, it is not necessary to pass an electric current through the plating solution to form a deposit. Electroless plating prevents corrosion and wear, and can be used to manufacture composite coatings by suspending powder in the bath.[1] EN plating creates an even layer regardless of the geometry of the surface – in contrast to electroplating which suffers from flux-density issues as an electric field will vary due to the surface profile and result in uneven depositions. Depending on the catalyst, EN plating can be applied to non-conductive surfaces.
  • 1.8K
  • 23 Nov 2022
Topic Review
Fundamentals of Precision Agriculture
Precision agriculture or precision farming is the targeted application of crop input according to the locally determined crop needs. Therefore, it is the geo-referenced application of crop inputs, whose rates should be those required by the crop. The most essential points of information about the topic being described are: overview; brief history of precision agriculture; theoretical basics of precision agriculture; precision agriculture cycle; geo-referenced measurement of within-field parameters; analysis and interpretation of geo-referenced data for mapping within-field parameters; spatially variable rate application of crop inputs; instruments for precision agriculture; current scenario of precision agriculture; current scenario of precision viticulture; Global Navigation Satellite Systems (GNSS) and differential correction technique; proximal sensors of within-field soil and crop parameters; remote sensing from Unmanned Aerial Vehicles (UAVs) and satellites; devices for setting up and controlling spatially variable rate crop input application; assisted guidance systems of agricultural machines; perspectives of precision agriculture.
  • 1.8K
  • 04 Feb 2023
Topic Review
Seed Priming Techniques
Presoaking seeds in water (hydropriming) or in a solution, usually of polyethylene glycol (PEG) or various salts at low water potential (osmopriming), has been demonstrated to improve the germination of seeds of numerous species including vegetables (carrot, celery, leek, lettuce, tomato), floral plants (cyclamen, primrose, pansy) and others (sugar beet, rape, soybean, sunflower). This treatment allows the germination stricto sensu to occur but prevents the radicle protrusion. Germination of primed seeds is more rapid and uniform than that of unprimed ones. Primed seeds germinate in a wider range of temperatures and are less sensitive to oxygen deprivation. Interestingly, priming also improves the germination of aged seeds.
  • 1.8K
  • 27 Mar 2023
Topic Review
Ubiquitylation-Mediated DNA Double-Strand Break Repair
The proper function of DNA repair is indispensable for eukaryotic cells since accumulation of DNA damages leads to genome instability and is a major cause of oncogenesis. Ubiquitylation and deubiquitylation play a pivotal role in the precise regulation of DNA repair pathways by coordinating the recruitment and removal of repair proteins at the damaged site. Here, we summarize the most important post-translational modifications (PTMs) involved in DNA double-strand break repair.
  • 1.8K
  • 13 Oct 2020
Topic Review
Glyphosate in Food
Glyphosate is a systemic, broad-spectrum and post-emergent herbicide. The use of glyphosate has grown in the last decades, and it is currently the most used herbicide worldwide. The rise of glyphosate consumption over the years also brought an increased concern about its possible toxicity and consequences for human health. 
  • 1.8K
  • 19 Nov 2021
Topic Review
Product–Service Systems for supply management of spare parts
A Product–Service System (PSS) can be considered as a combination of customer life cycle-oriented products and services that are provided by means of an extended value creation network. Such a business model fosters the transition from a tangible goods-dominant logic to an intangible goods-dominant one and accomplishes Circular Economy (CE) principles. In fact, the services interwoven with a product’s life cycle, especially those related to its use and End-Of-Life (EOL) phases, play a crucial role in the optimization of the environmental performances of a product through its whole life cycle. However, PSS solutions aimed at practically optimizing supply chain management have scarcely been addressed. In order to reduce this gap, here proposes a procedure based on the PSS Functional Matrix, the Screening Life Cycle Modelling (SLCM) method, and stock management theory to optimize aftermarket services based on market demand.
  • 1.8K
  • 04 Mar 2022
Topic Review
Afghan Presidential Election, 2009
Presidential elections were held in Afghanistan on 20 August 2009. The election resulted in victory for incumbent Hamid Karzai, who won 49.67% of the vote, while his main rival Abdullah Abdullah finished second with 30.59% of the vote. The election was characterized by lack of security, low voter turnout and low awareness of the people about the election and election process and widespread ballot stuffing, intimidation, and other electoral fraud. A second round run-off vote, announced under heavy U.S. and ally pressure, was originally scheduled for 7 November 2009, but it was cancelled after Abdullah refused to participate, and Hamid Karzai was declared President of Afghanistan for another 5-year term. The election was the second under the present constitution of Afghanistan and was held on the same day as elections for 34 provincial council seats. The Taliban called for a boycott of the election, describing it as a "program of the crusaders" and "this American process".
  • 1.8K
  • 16 Nov 2022
Topic Review
Non-Deterministic Turing Machine
In theoretical computer science, a Turing machine is a theoretical machine that is used in thought experiments to examine the abilities and limitations of computers.
  • 1.8K
  • 28 Nov 2022
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