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Topic Review
Mechanical Properties of Implant in Lumbar Interbody Fusion
Over the last decade, pedicle fixation systems have evolved and modifications in spinal fusion techniques have been developed to increase fusion rates and improve clinical outcomes after lumbar interbody fusion (LIF). Regarding materials used for screw and rod manufacturing, metals, especially titanium alloys, are the most popular resources. In the case of pedicle screws, that biomaterial can be also doped with hydroxyapatite, CaP, ECM, or tantalum. Other materials used for rod fabrication include cobalt–chromium alloys and nitinol (nickel–titanium alloy). In terms of mechanical properties, the ideal implant used in LIF should have high tensile and fatigue strength, Young’s modulus similar to that of the bone, and should be 100% resistant to corrosion to avoid mechanical failures.
  • 1.6K
  • 08 Jun 2022
Topic Review
Restoration of Soils and Groundwater Contaminated by Explosives
Soil pollution resulting from explosives represents a critical environmental challenge. While physical methods like excavation and disposal are effective, their applicability is constrained by cost and logistical challenges for large contaminated areas. Chemical methods, such as oxidation and reduction, focus on transforming explosives into less toxic byproducts. Biological remediation utilizing plants and microorganisms emerges as a cost-effective and sustainable alternative. 
  • 1.6K
  • 31 Jan 2024
Topic Review
Grape Anthocyanins
Anthocyanins are flavonoid pigments broadly distributed in plants with great potential to be used as food colorants due to their range of colors, innocuous nature, and positive impact on human health. However, these molecules are unstable and affected by pH changes, oxidation and high temperatures, making it very important to extract them using gentle non-thermal technologies.
  • 1.6K
  • 02 Dec 2021
Topic Review
T Helper Cells in IBD
Inflammatory bowel disease (IBD) is a chronic disorder manifested as Crohn’s disease (CD) and ulcerative colitis (UC) characterized by intestinal inflammation and involves a dysregulated immune response against commensal microbiota through the activation of CD4 T helper cells. T helper cell differentiation to effector or regulatory phenotypes is controlled by cytokine networks and transcriptional regulators. Distinct polarized T helper cells are able to alter their phenotypes to adapt to diverse and fluctuating physiological environments. T helper cells exhibit intrinsic instability and flexibility to express cytokines of other lineages or transdifferentiate from one T helper cell type to another in response to various perturbations from physiological cytokine milieu as a means of promoting local immunity in response to injury or ensure tissue homeostasis. Furthermore, functional plasticity and diversity of T helper cells are associated with pathogenicity and are critical for immune homeostasis and prevention of autoimmunity. In this review, we provide deeper insights into the combinatorial extrinsic and intrinsic signals that control plasticity and transdifferentiation of T helper cells and also highlight the potential of exploiting the genetic reprogramming plasticity of T helper cells in the treatment of IBD.
  • 1.6K
  • 28 Oct 2020
Topic Review
Epigenetics and pancreatic cancer progression
Due to the lack of diagnostic biomarkers and high resistance to treatment, pancreatic ductal adenocarcinoma (PDAC) represents one of the most lethal solid tumors with poor survival. Moreover, the metastatic potential of PDAC is extremely high and tumors spread mainly through lymphatic and blood vessels. Although genetic modifications are well defined in PDAC, the role of epigenetics regulations, which secure dynamic response to environmental stimuli, has only recently been recognized. Epigenomic studies revealed that epigenetic changes in oncogenes and tumor suppressor genes were associated with epithelial-mesenchymal transition (EMT) which is responsible for the invasive phenotype of cancer cells and therefore, their metastatic potential. 
  • 1.6K
  • 18 Jan 2021
Topic Review
Porphyrins/Chlorins for Viruses Inactivation
The problem of treating viral infections is extremely important both in connection with the emergence of new viral diseases and in connection with the low efficiency of existing approaches to the treatment of known viral infections. This entry is devoted to the use of porphyrins, chlorins, and phthalocyanines for the fight against viral infections using chemical and photochemical inactivation methods. The purpose of this work is to summarize the main approaches developed to date to chemical and photodynamic inactivation of human and animal viruses using porphyrins and their analogs, as well as to analyze and discuss information on viral targets and antiviral activity of porphyrins, chlorins and their derivatives obtained in the last 10-15 years, in order to identify the most promising areas.
  • 1.6K
  • 23 Jun 2021
Topic Review
Properties of Wire Arc-Sprayed Fe-Based Coatings
Among different thermal spraying methods, arc-spraying has been widely used due to its low operating costs and high deposition efficiency. The rapid progress of cored wire technology in arc-spraying has increased possibilities for the preparation of new Fe-based coating materials with enhanced properties by adding reinforcement particles and alloying elements to suit the different applications. 
  • 1.6K
  • 09 Mar 2022
Topic Review
Political Divisions and Socio-Economic Disparities in Poland
In the past 30 years, Poland has undergone a spectacular transformation from a backward post-communist country into one of the most dynamically growing members of the European Union (EU). However, persisting and even progressing inter- and intra-regional divergence constitutes a growing threat to sustainable development. Increasing developmental differences have been met with growing social opposition, fostering populist tendencies. It should be noted that the costs and benefits of globalisation under the conditions of progressive integration are unevenly distributed both in terms of territories and social groups. This has led not only to the aforementioned developmental differentiation of territories, but also (and perhaps above all) to the polarisation of social views. Unfortunately, in both cases the scale of polarisation has become dangerous. This raises the research relevance on the impact of regional differentiation on electoral preferences.
  • 1.6K
  • 23 Dec 2021
Topic Review
Quantum Stream Cipher
Quantum cryptography includes quantum key distribution (QKD) and quantum stream cipher, but the researchers point out that the latter is expected as the core technology of next-generation communication systems. Various ideas have been proposed for QKD quantum cryptography, but most of them use a single-photon or similar signal. Then, although such technologies are applicable to special situations, these methods still have several difficulties to provide functions that surpass conventional technologies for social systems in the real environment. Thus, the quantum stream cipher has come to be expected as one promising countermeasure, which artificially creates quantum properties using special modulation techniques based on the macroscopic coherent state. In addition, it has the possibility to provide superior security performance than one-time pad cipher.
  • 1.6K
  • 25 May 2022
Topic Review
Association between Internal Control and Sustainability
With the integration of sustainable development into all aspects of the economy, politics, society, culture, and ecology, the effectiveness and innovation of enterprises in sustainability have become global research issues. Internal control affects the current operation and management as the main means for enterprises to maintain normal production and operation and prevent risks. Internal control has, on the one hand, positive effects on enterprise sustainability by improving the quality of financial information, derived effects, and spillover effects. However, on the other hand, internal control can be detrimental to enterprise sustainability by increasing compliance costs and legal liabilities. 
  • 1.6K
  • 12 Aug 2022
Topic Review
Coherence Therapy
Coherence therapy is a system of psychotherapy based in the theory that symptoms of mood, thought and behavior are produced coherently according to the person's current mental models of reality, most of which are implicit and unconscious. It was founded by Bruce Ecker and Laurel Hulley in the 1990s. It has been considered among the most well respected postmodern/constructivist therapies.
  • 1.6K
  • 29 Sep 2022
Topic Review
Dynamical System (Definition)
The dynamical system concept is a mathematical formalization for any fixed "rule" that describes the time dependence of a point's position in its ambient space. The concept unifies very different types of such "rules" in mathematics: the different choices made for how time is measured and the special properties of the ambient space may give an idea of the vastness of the class of objects described by this concept. Time can be measured by integers, by real or complex numbers or can be a more general algebraic object, losing the memory of its physical origin, and the ambient space may be simply a set, without the need of a smooth space-time structure defined on it.
  • 1.6K
  • 10 Oct 2022
Topic Review
LPC (Programming Language)
LPC (short for Lars Pensjö C) is an object-oriented programming language derived from C and developed originally by Lars Pensjö to facilitate MUD building on LPMuds. Though designed for game development, its flexibility has led to it being used for a variety of purposes, and to its evolution into the language Pike. LPC syntax places it in the family of C-like languages, with C and C++ its strongest influences.
  • 1.6K
  • 25 Oct 2022
Topic Review
Acraea (Genus)
Acraea is a genus of brush-footed butterflies (family Nymphalidae) of the subfamily Heliconiinae. It seems to be highly paraphyletic and has long been used as a "wastebin taxon" to unite about 220 species of anatomically conservative Acraeini. Some phylogenetic studies show that the genus Acraea is monophyletic if Bematistes and Neotropical Actinote are included (see Pierre & Bernaud, 2009). Most species assembled here are restricted to the Afrotropic ecozone, but some are found in India , Southeast Asia, and Australia .
  • 1.6K
  • 15 Nov 2022
Topic Review
Next-Generation Sequencing in the Human Respiratory Virome Study
Next-generation sequencing (NGS) is widely used to study microorganisms, allowing the elucidation of bacteria and viruses inhabiting different body systems and identifying new pathogens. 
  • 1.6K
  • 09 Dec 2022
Topic Review
Arsenic on Plants and Strategies for Mitigation
Arsenic contamination in soil and water is a major problem worldwide. Inorganic arsenic is widely present as arsenate and arsenite. Arsenic is transferred to crops through the soil and irrigation water. It is reported to reduce crop production in plants and can cause a wide array of diseases in humans, including different types of cancers, premature delivery, stillbirth, and spontaneous abortion. Arsenic methyltransferase (AS3MT) in the human body converts inorganic arsenic into monomethylarsonic acid and dimethylarsinic acid, which are later excreted from the body. Arsenic transfer from the soil to grains of rice involves different transporters such as Lsi1, Lsi2, and Lsi6. These transporters are also required for the transfer of silicate, which makes them important for the plant. 
  • 1.6K
  • 27 Feb 2023
Topic Review
Mechanisms of Skin Aging Processes
With the advancement of living standards in modern society and the emergence of an aging population, an increasing number of people are becoming interested in the topic of aging and anti-aging. An important feature of aging is skin aging, and women are particularly concerned about skin aging. In the field of cosmetics, the market share of anti-aging products is increasing year by year.
  • 1.6K
  • 01 Aug 2023
Topic Review
Commercial Applications of Chlorella sp. and Spirulina sp.
Microalgae are a large and polyphyletic group of O2-evolving photosynthetic microorganisms, mostly aquatic, comprising prokaryotic cyanobacteria and eukaryotic members. Estimates of the world microalgal production are around 50.000 t/year, Chlorella sp. and Spirulina sp. accounting for more than 90% of the total microalgal biomass production.  These microorganisms have been widely recognized for their nutritional and therapeutic properties; therefore, a significant growth of their market is expected, especially in the nutraceutical, food, and beverage segments.
  • 1.6K
  • 14 Aug 2023
Topic Review
MCPIP1
MCPIP1 (also known as regnase-1) is encoded by the ZC3H12A gene and is composed of 599 amino acids that encode a 66-kDa protein. MCPIP1 is a potent anti-inflammatory protein, and plays many roles within the regulation of the immune response.
  • 1.6K
  • 22 Oct 2020
Topic Review
Additive Manufacturing of Ti-Based Alloys
TiAl-based intermetallic alloys have come to the fore as the preferred alloys for high-temperature applications. Conventional methods (casting, forging, sheet forming, extrusion, etc.) have been applied to produce TiAl intermetallic alloys. However, the inherent limitations of conventional methods do not permit the production of the TiAl alloys with intricate geometries. Additive manufacturing technologies such as electron beam melting (EBM) and laser powder bed fusion (LPBF), have been used to produce TiAl alloys with complex geometries. EBM technology can produce crack-free TiAl components but lacks geometrical accuracy. LPBF technology has great geometrical precision that could be used to produce TiAl alloys with tailored complex geometries, but cannot produce crack-free TiAl components. To satisfy the current industrial requirement of producingcrack-free TiAl alloys with tailored geometries, the paper proposes a new heating model for the LPBF manufacturing process. The model could maintain even temperature between the solidified and subsequent layers, reducing temperature gradients (residual stress), which could eliminate crack formation. The new conceptualized model also opens a window for in-situ heat treatment of the built samples to obtain the desired TiAl (gama-phase) and Ti3Al (α2-phase) intermetallic phases for high-temperature operations. In situ heat treatment would also improve the homogeneity of the microstructure of LPBF manufactured samples.
  • 1.6K
  • 26 Aug 2021
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