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Topic Review
Resistance of Concretes to External Chlorides
Corrosion of steel reinforcement due to chloride attack remains a major reinforced concrete durability concern. The problem is prevalent for concrete structures located within marine environments or frost-prone locations where chlorides containing de-icing salts are used. 
  • 1.5K
  • 10 Jan 2023
Topic Review
Phycobilisomes and Phycobiliproteins
Eukaryotic photosynthesis arose in the course of evolution as a result of the incorporation of an unstored cyanobacterium and its transformation into chloroplasts by an ancestral heterotrophic eukaryotic cell. The pigment apparatus of earlier evolved  Archaeplastida algae and other later algal phyla turned out to be arranged in the same way having pigment-protein complexes of photosystem I (PS I), photosystem II (PS II) and antenna complex. PS I and PS II are characterized by uniform structures, while the light-harvesting antennae have undergone a number  of changes.
  • 1.5K
  • 14 Feb 2023
Topic Review
Molecular Mechanisms of Colistin Resistance in Acinetobacter baumannii
Colistin, as a positively charged peptide, exerts its antibacterial effect via electrostatic interactions with negatively charged lipid A, a component of lipopolysaccharide (LPS). Accordingly, two main mechanisms of colistin resistance have been described in Acinetobacter baumannii (A. baumannii): the complete loss or modifications of the target LPS, leading to abolishing or reducing its negative charge. The complete loss of LPS results from inactivation of the first three genes of the lipid A biosynthetic pathway (lpxA, lpxC, and lpxD genes), whereas the modification of LPS occurs through the addition of phosphoethanolamine (PEtN) moieties to lipid A by the pmrCAB operon-encoded enzymes. Although 4-amino-4-deoxy-L-arabinose (L-Ara4N) modification of LPS has been described as a more common and effective colistin resistance mechanism compared to PEtN LPS modification in diverse Gram-negative pathogens (Salmonella enterica, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa), it was absent in A. baumannii. In addition to chromosome-mediated mechanisms, plasmid-mediated colistin resistance encoded by mcr genes has been recognized as a major driver of rapid dissemination by horizontal gene transfer among pathogenic Gram-negative bacteria, including A. baumannii.
  • 1.5K
  • 21 Mar 2023
Topic Review
Detection of Biological Molecules Using Nanopore Sensing Techniques
Usually, in the early stages of the disease, the number of specific biomarkers is very low and sometimes difficult to detect using classical diagnostic methods. Among detection methods, biosensors have advantages such as easy operation, speed, and portability, with additional benefits of low costs and repeated reliable results. Single-molecule sensors such as nanopores that can detect biomolecules at low concentrations have the potential to become clinically relevant. As such, several applications have been introduced in this field for the detection of blood markers, nucleic acids, or proteins. The use of nanopores has yet to reach maturity for standardization as diagnostic techniques, however, they promise enormous potential, as progress is made into stabilizing nanopore structures, enhancing chemistries, and improving data collection and bioinformatic analysis.
  • 1.5K
  • 19 Jun 2023
Topic Review
Role of Riboflavin in Poultry Nutrition
Riboflavin, an essential B-vitamin, plays a crucial role in poultry metabolism, impacting energy production, growth, and immune regulation. Its role in redox reactions and energy metabolism is vital for optimal growth and development. Riboflavin is essential for adenosine triphosphate (ATP) production and the conversion of tryptophan into niacin. Deficiency can lead to skeletal deformities, impaired growth, and compromised immune function. Dietary riboflavin supplementation is necessary due to variable bioavailability in plant-derived sources. The vitamin is absorbed through specialized transport proteins, and its cellular uptake is facilitated by specific receptors. Riboflavin’s role in protein synthesis and its antioxidant properties influence poultry growth and defense against oxidative stress. Its impact on reproductive performance, hatchability, and overall poultry health underscores its significance in poultry nutrition.
  • 1.5K
  • 22 Nov 2023
Topic Review
Inflammatory Bowel Diseases in Dogs
Canine inflammatory bowel diseases (IBD) are of increasing interest in veterinary medicine. They refer to complex and debilitating conditions of dogs’ gastrointestinal tract. Although little evidence for causal inferences is currently available, it is believed that IBD pathophysiology entails intricate interactions between environmental factors, the intestinal immune system, and the microbial communities that colonize the gut. To better understand the mechanisms underlying these disorders, leveraging factors associated with the development of these diseases is imperative. Of these factors, emerging evidence supports the role of dietary patterns as key players influencing the composition and function of gut microbes, with subsequent effects on health and disease.
  • 1.5K
  • 01 Dec 2022
Topic Review
Type 1 Fimbriae (Pili)
Type 1 fimbriae (pili) are an important colonization factor that can contribute to diseases such as urinary tract infections and neonatal meningitis.
  • 1.5K
  • 10 Jan 2022
Topic Review
Molecular Mechanism between Scion and Rootstock
Most tree fruits are commercially grown on different root systems, hence called composite plants. The section provides the root system as the rootstock, and the atop ground portion is called the scion. The combination is selected based on different traits of scion varieties, rootstock, and prevailing edaphic situations. Rootstock selection is one of the most important factors in orchard management because it affects the growth, nutrient accumulation, environmental tolerance, and fruit quality of scion varieties.
  • 1.5K
  • 20 Dec 2022
Topic Review
Electrochemical Sensors for Quantification of Glycated Hemoglobin
Glycated hemoglobin (HbA1c), one of the many variants of hemoglobin (Hb), serves as a standard biomarker of diabetes, as it assesses the long-term glycemic status of the individual for the previous 90–120 days. HbA1c levels in blood are stable and do not fluctuate when compared to the random blood glucose levels. The normal level of HbA1c is 4–6.0%, while concentrations > 6.5% denote diabetes. 
  • 1.5K
  • 25 Feb 2023
Topic Review
Bimetallic Ni-Based Catalysts CO2 Methanation
CO2 methanation has recently emerged as a process that targets the reduction in anthropogenic CO2 emissions, via the conversion of CO2 captured from point and mobile sources, as well as H2 produced from renewables into CH4. Ni, among the early transition metals, as well as Ru and Rh, among the noble metals, have been known to be among the most active methanation catalysts, with Ni being favoured due to its low cost and high natural abundance. However, insufficient low-temperature activity, low dispersion and reducibility, as well as nanoparticle sintering are some of the main drawbacks when using Ni-based catalysts. Such problems can be partly overcome via the introduction of a second transition metal (e.g., Fe, Co) or a noble metal (e.g., Ru, Rh, Pt, Pd and Re) in Ni-based catalysts. Through Ni-M alloy formation, or the intricate synergy between two adjacent metallic phases, new high-performing and low-cost methanation catalysts can be obtained.
  • 1.5K
  • 12 May 2021
Topic Review
Seed-Layer Free ZnSnO3 Nanowires
ZnSnO3 semiconductor nanostructures have several applications as photocatalysis, gas sensors, and energy harvesting. However, due to its multicomponent nature, the synthesis is far more complex than its binary counter parts. The complexity increases even more when aiming for low-cost and low-temperature processes as in hydrothermal methods. Knowing in detail the influence of all the parameters involved in these processes is imperative, in order to properly control the synthesis to achieve the desired final product. Thus, this paper presents a study of the influence of the physical parameters involved in the hydrothermal synthesis of ZnSnO3 nanowires, namely volume, reaction time, and process temperature. Based on this study a growth mechanism for the complex Zn:Sn:O system is proposed. Two zinc precursors, zinc chloride and zinc acetate, were studied, showing that although the growth mechanism is inherent to the material itself, the chemical reactions for different conditions need to be considered.
  • 1.5K
  • 24 Sep 2020
Topic Review
Negative Emotions in Career Decision-Making
Within the context of career counseling, clients often regard negatives feelings toward vocational options as inconsequential. Regrettably, by doing so, they discount the significance of the affect and overlook an important source of information. In the following study, Puffer and Pence investigated college students' negative emotional reactions to self- or computer reported occupations and the rationales for the selection of the negative affect. Their findings reveal how negative emotionality can be adaptive and feasibly assist career decision-makers.   
  • 1.5K
  • 02 Dec 2020
Topic Review
Tumor Cells and Cancer-Associated Fibroblasts
Metabolism is considered to be the core of all cellular activity. Thus, extensive studies of metabolic processes are ongoing in various fields of biology, including cancer research. Cancer cells are known to adapt their metabolism to sustain high proliferation rates and survive in unfavorable environments with low oxygen and nutrient concentrations. Hence, targeting cancer cell metabolism is a promising therapeutic strategy in cancer research. However, cancers consist not only of genetically altered tumor cells but are interwoven with endothelial cells, immune cells and fibroblasts, which together with the extracellular matrix (ECM) constitute the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs), which are linked to poor prognosis in different cancer types, are one important component of the TME. CAFs play a significant role in reprogramming the metabolic landscape of tumor cells, but how, and in what manner, this interaction takes place remains rather unclear.
  • 1.5K
  • 04 Mar 2021
Topic Review
Actual Symmetry of Symmetric Adducts
This review discusses molecular adducts, whose composition allows a symmetric structure. Such adducts are popular model systems, as they are useful for analyzing the effect of structure on the property selected for study since they allow one to reduce the number of parameters. The main objectives of this discussion are to evaluate the influence of the surroundings on the symmetry of these adducts, steric hindrances within the adducts, competition between different noncovalent interactions responsible for stabilizing the adducts, and experimental methods that can be used to study the symmetry at different time scales. This review considers the following central binding units: hydrogen (proton), halogen (anion), metal (cation), water (hydrogen peroxide). 
  • 1.5K
  • 10 Feb 2022
Topic Review
Steroidogenesis, Oxidative Stress and Male Hypogonadism
Steroid sex hormones are classified as androgens, estrogens, and progestogens. Although all three classes are important in male and female physiology, androgens are associated with "musculisation" effects and are considered primarily male sex hormones. Androgens have diverse functions in muscle physiology, lean body mass, the regulation of adipose tissue, bone density, neurocognitive regulation, and spermatogenesis, male reproductive and sexual function.
  • 1.5K
  • 29 Mar 2022
Topic Review
Measuring Online Sensory Consumer Experience
Customers often consider that the information and visualizations of the product do not align with reality and entail a degree of uncertainty. To reduce the perceived risk of buying online, consumers strive to experience diverse components of e-commerce websites, predominantly sensory communication (e.g., high-quality pictures).
  • 1.5K
  • 15 Jun 2022
Topic Review
Colorectal Cancer Treatment Based on Nanomaterials
Colorectal cancer (CRC) is a global health problem responsible for 10% of all cancer incidences and 9.4% of all cancer deaths worldwide. The number of new cases increases per annum, whereas the lack of effective therapies highlights the need for novel therapeutic approaches. Conventional treatment methods, such as surgery, chemotherapy and radiotherapy, are widely applied in oncology practice. Their therapeutic success is little, and therefore, the search for novel technologies is ongoing. Many efforts have focused recently on the development of safe and efficient cancer nanomedicines. Nanoparticles are among them. They are unique with their properties on a nanoscale and hold the potential to exploit intrinsic metabolic differences between cancer and healthy cells. This feature allows them to induce high levels of toxicity in cancer cells with little damage to the surrounding healthy tissues.
  • 1.5K
  • 21 Jul 2022
Topic Review
Solar-Assisted Heat Pump for Buildings in China
The building sector accounts for over 40% of global energy consumption. The utilization of renewable energy systems such as the solar-assisted heat pump (SAHP) in buildings has been shown to improve building energy efficiency and achieve carbon neutrality.
  • 1.5K
  • 22 Sep 2022
Topic Review
Biodegradable Polymers in Triboelectric Nanogenerators
Triboelectric nanogenerators (TENGs) have attracted much attention because they not only efficiently harvest energy from the surrounding environment and living organisms but also serve as multifunctional sensors toward the detection of various chemical and physical stimuli. In particular, biodegradable TENG (BD-TENG) represents an emerging type of self-powered device that can be degraded, either in physiological environments as an implantable power source without the necessity of second surgery for device retrieval, or in the ambient environment to minimize associated environmental pollution.
  • 1.5K
  • 14 Feb 2023
Topic Review
Antecedents of Electric Vehicle Purchase Intention
Global sales of electric vehicles (EVs) have grown steadily; however, their worldwide market share is still less than 10%. The antecedents were classified into three main categories: consumer characteristics, EV characteristics, and EV-related policies. A summary model represents the impact information of each of the main antecedents. 
  • 1.5K
  • 06 May 2023
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