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Topic Review
Near-Haploidy and Low-Hypodiploidy in B-Cell Acute Lymphoblastic Leukemia
B-cell acute lymphoblastic leukemia (B-ALL) is characterized by an uncontrolled proliferation of blood cells in the bone marrow. Hypodiploidy with less than 40 chromosomes is a rare genetic abnormality in B-cell acute lymphoblastic leukemia (B-ALL). This condition can be classified based on modal chromosome number as low-hypodiploidy (30–39 chromosomes) and near-haploidy (24–29 chromosomes), with unique cytogenetic and mutational landscapes. 
  • 1.7K
  • 10 Jan 2022
Topic Review
Injection Molding of Long Glass Fiber-Reinforced Phenolic Resins
Glass fiber-reinforced phenolic resins are well suited to substitute aluminum die-cast materials. They meet the high thermomechanical and chemical demands that are typically found in combustion engine and electric drive train applications. An injection molding process development for further improving their mechanical properties by increasing the glass fiber length in the molded part was conducted. A novel screw mixing element was developed to improve the homogenization of the long fibers in the phenolic resin. The process operation with the mixing element is a balance between the desired mixing action, an undesired preliminary curing of the phenolic resin, and the reduction of the fiber length. 
  • 1.7K
  • 15 Aug 2022
Topic Review
Vaccinia
Vaccinia virus (VACV or VV) is a large, complex, enveloped virus belonging to the poxvirus family. It has a linear, double-stranded DNA genome approximately 190 kbp in length, which encodes approximately 250 genes. The dimensions of the virion are roughly 360 × 270 × 250 nm, with a mass of approximately 5–10 fg. The vaccinia virus is the source of the modern smallpox vaccine, which the World Health Organisation used to eradicate smallpox in a global vaccination campaign in 1958–1977. Although smallpox no longer exists in the wild, vaccinia virus is still studied widely by scientists as a tool for gene therapy and genetic engineering. Smallpox had been an endemic human disease that had a 30% fatality rate. In 1796, the British doctor Edward Jenner proved that an infection with the relatively mild cowpox virus would also confer immunity to the deadly smallpox. Jenner referred to cowpox as variolae vaccinae (smallpox of the cow). However, the origins of the smallpox vaccine became murky over time, especially after Louis Pasteur developed laboratory techniques for creating vaccines in the 19th century. Allan Watt Downie demonstrated in 1939 that the modern smallpox vaccine was serologically distinct from cowpox, and vaccinia was subsequently recognized as a separate viral species. Whole-genome sequencing has revealed that vaccinia is most closely related to horsepox, and the cowpox strains found in Great Britain are the least closely related to vaccinia.
  • 1.7K
  • 19 Oct 2022
Topic Review
Positive and Negative Affect Schedule
The Positive and Negative Affect Schedule (PANAS) is a self-report questionnaire that consists of two 10-item scales to measure both positive and negative affect. Each item is rated on a 5-point scale of 1 (not at all) to 5 (very much). The measure has been used mainly as a research tool in group studies, but can be utilized within clinical and non-clinical populations as well. Shortened, elongated, and children's versions of the PANAS have been developed, taking approximately 5–10 minutes to complete. Clinical and non-clinical studies have found the PANAS to be a reliable and valid instrument in the assessment of positive and negative affect.
  • 1.7K
  • 28 Oct 2022
Topic Review
Object
An object is a philosophical term often used in contrast to the term subject. A subject is an observer and an object is a thing observed. For modern philosophers like Descartes, consciousness is a state of cognition that includes the subject—which can never be doubted as only it can be the one who doubts—and some object(s) that may be considered as not having real or full existence or value independent of the subject who observes it. Metaphysical frameworks also differ in whether they consider objects existing independently of their properties and, if so, in what way. The pragmatist Charles S. Peirce defines the broad notion of an object as anything that we can think or talk about. In a general sense it is any entity: the pyramids, gods, Socrates, Alpha Centauri, the number seven, a disbelief in predestination or the fear of cats. In a strict sense it refers to any definite being. A related notion is objecthood. Objecthood is the state of being an object. One approach to defining it is in terms of objects' properties and relations. Descriptions of all bodies, minds, and persons must be in terms of their properties and relations. The philosophical question of the nature of objecthood concerns how objects are related to their properties and relations. For example, it seems that the only way to describe an apple is by describing its properties and how it is related to other things. Its properties may include its redness, its size, and its composition, while its relations may include "on the table", "in the room" and "being bigger than other apples". The notion of an object must address two problems: the change problems and the problems of substances. Two leading theories about objecthood are substance theory, wherein substances (objects) are distinct from their properties, and bundle theory, wherein objects are no more than bundles of their properties.
  • 1.7K
  • 04 Nov 2022
Topic Review
Folk Art
Folk art covers all forms of visual art made in the context of folk culture. Definitions vary, but generally the objects have practical utility of some kind, rather than being exclusively decorative. The makers of folk art are normally trained within a popular tradition, rather than in the fine art tradition of the culture. There is often overlap, or contested ground, with naive art, but in traditional societies where ethnographic art is still made, that term is normally used instead of "folk art". The types of object covered by the term varies considerably and in particular "divergent categories of cultural production are comprehended by its usage in Europe, where the term originated, and in the United States, where it developed for the most part along very different lines." Folk arts are rooted in and reflective of the cultural life of a community. They encompass the body of expressive culture associated with the fields of folklore and cultural heritage. Tangible folk art includes objects which historically are crafted and used within a traditional community. Intangible folk arts include such forms as music, dance and narrative structures. Each of these arts, both tangible and intangible, was originally developed to address a real need. Once this practical purpose has been lost or forgotten, there is no reason for further transmission unless the object or action has been imbued with meaning beyond its initial practicality. These vital and constantly reinvigorated artistic traditions are shaped by values and standards of excellence that are passed from generation to generation, most often within family and community, through demonstration, conversation, and practice.
  • 1.7K
  • 15 Nov 2022
Topic Review
Bad Breath
Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder. The concerns of bad breath may be divided into genuine and non-genuine cases. Of those who have genuine bad breath, about 85% of cases come from inside the mouth. The remaining cases are believed to be due to disorders in the nose, sinuses, throat, lungs, esophagus, or stomach. Rarely, bad breath can be due to an underlying medical condition such as liver failure or ketoacidosis. Non-genuine cases occur when someone feels they have bad breath but someone else cannot detect it. This is estimated to make up between 5% and 72% of cases. The treatment depends on the underlying cause. Initial efforts may include tongue cleaning, mouthwash, and flossing. Tentative evidence supports the use of mouthwash containing chlorhexidine or cetylpyridinium chloride. While there is tentative evidence of benefit from the use of a tongue cleaner it is insufficient to draw clear conclusions. Treating underlying disease such as gum disease, tooth decay, or gastroesophageal reflux disease may help. Counselling may be useful in those who falsely believe that they have bad breath. Estimated rates of bad breath vary from 6% to 50% of the population. Concern about bad breath is the third most common reason people seek dental care, after tooth decay and gum disease. It is believed to become more common as people age. Bad breath is viewed as a social taboo and those affected may be stigmatized. People in the United States spend more than $1 billion per year on mouthwash to treat the condition.
  • 1.7K
  • 23 Nov 2022
Topic Review
The SIFT-MS Technique
Selected ion flow tube mass spectrometry (SIFT-MS) uses soft chemical ionization (CI) to generate mass-selected reagent ions that can rapidly react with and quantify VOCs down to part-per-trillion concentrations (by volume, pptV). Up to eight reagent ions (H3O+, NO+, O2+, O-, OH-, O2-, NO2- and NO3-) obtained from a microwave discharge in air are available on SIFT-MS instruments. These reagent ions react with VOCs and other trace analytes in well-controlled ion-molecule reactions, but they do not react with the major components of air (N2, O2, CO2 and Ar). This enables direct, real-time analysis of air samples to be achieved at trace and ultra-trace levels without pre-concentration. Rapid switching between reagent ions provides high selectivity because the multiple reaction mechanisms give independent measurements of each analyte. 
  • 1.7K
  • 28 Apr 2023
Topic Review
Cell-Type Annotation
Multicellular organisms consist of cells that can be categorized by their function and morphology. Single-cell transcriptomics makes it possible to individually profile thousands of cells in multiple tissues and organisms within a single experiment. Determining and labeling cell types or states in single cell transcriptomic data is known as cell-type annotation or identification. Several methods are employed for cell-type annotation, including signature scoring, supervised learning, cell-integration-based label transfer, and semi-supervised annotation. Considering the lineage relationships among cell types, hierarchical classification methods are crucial for accurately identifying cell types and subtypes at an optimal clustering resolution. The use of well-curated reference datasets, implementation of quality control measures, and careful consideration of cluster resolutions heavily influence the reliability of cell-type annotation. The aim of cell-type annotation is to gain insights into cell heterogeneity in various biological processes and diseases, with the potential to drive improvements in therapeutic interventions.
  • 1.7K
  • 08 Aug 2023
Topic Review
Dental Implants Materials
The development of dental implantology is based on the detailed study of the interaction of implants with the surrounding tissues and methods of osteogenesis stimulation around implants, which has been confirmed by the increasing number of scientific publications presenting the results of studies related to both the influence of the chemical composition of dental implant material as well as the method of its surface modification on the key operational characteristics of implants.
  • 1.7K
  • 06 Dec 2023
Topic Review
Steel Fibers on Tensile Properties of Ultra-High-Performance Concrete
Ultra-high-performance concrete (UHPC) is an advanced cement-based material with excellent mechanical properties and durability. However, with the improvement of UHPC’s compressive properties, its insufficient tensile properties have gradually attracted attention.
  • 1.7K
  • 11 Mar 2024
Topic Review
Antidiabetic Properties of Curcumin II
Type 2 diabetes mellitus (T2DM) is a growing metabolic disease characterized by insulin resistance and hyperglycemia. Current preventative and treatment approaches to insulin resistance and T2DM lack in efficacy, resulting in the need for new approaches to prevent and treat the disease. In recent years, epidemiological studies have suggested that diets rich in fruits and vegetables have beneficial health effects, including protection against insulin resistance and T2DM. Curcumin, a polyphenol found in turmeric, and curcuminoids have been reported to have antioxidant, anti-inflammatory, hepatoprotective, nephroprotective, neuroprotective, immunomodulatory and antidiabetic properties. Here we are summarizing the existing in vivo studies examining the antidiabetic effects of curcumin.
  • 1.7K
  • 29 Oct 2020
Topic Review
Leaf Molecular and Hormonal Regulation
Shoot apical meristems (SAM) are tissues that function as a site of continuous organogenesis, which indicates that a small pool of pluripotent stem cells replenishes into lateral organs. The coordination of intercellular and intracellular networks is essential for maintaining SAM structure and size and also leads to patterning and formation of lateral organs. Leaves initiate from the flanks of SAM and then develop into a flattened structure with variable sizes and forms. This process is mainly regulated by the transcriptional regulators and mechanical properties that modulate leaf development. Leaf initiation along with proper orientation is necessary for photosynthesis and thus vital for plant survival. Leaf development is controlled by different components such as hormones, transcription factors, miRNAs, small peptides, and epigenetic marks. Moreover, the adaxial/abaxial cell fate, lamina growth, and shape of margins are determined by certain regulatory mechanisms. The over-expression and repression of various factors responsible for leaf initiation, development, and shape have been previously studied in several mutants. However, in this review, we collectively discuss how these factors modulate leaf development in the context of leaf initiation, polarity establishment, leaf flattening and shape.
  • 1.7K
  • 27 Oct 2020
Topic Review
Tungurahua Volcano (Ecuador)
Since April of 2015, the ash dispersion and ash fallout due to Vulcanian eruptions at Tungurahua, one of the most active volcanoes in Ecuador, have been forecasted daily. For this purpose, our forecasting system uses the meteorological Weather Research and Forecasting (WRF) and the FALL3D models. Previously, and based on field data, laboratory, and numerical studies, corresponding eruption source parameters (ESP) have been defined. We analyzed the historically forecasted results of the ash fallout quantities over four years (April 2015 to March 2019), in order to obtain the average isomass and probability maps for three-month periods: February–March–April (FMA), May–June–July (MJJ), August–September–October (ASO), and November–December–January (NDJ). Our results indicate similar ash fallout shapes during MJJ and ASO, with a clear and defined tendency toward the west of the volcano; this tendency is less defined during NDJ and FMA. The proximal region west of the volcano (about 100 km to the west) has the highest probability (>70%) of being affected by ash fallout. The distant region to the west (more than 100 km west) presented low to medium probabilities (10%–70%) of ash fallout. The cities of Guaranda (W, 60% to 90%), Riobamba (SW, 70%), and Ambato (NW, 50% to 60%) have the highest probabilities of being affected by ash fallout. Among the large Ecuadorian cities, Guayaquil (SW, 10% to 30%) has low probability, and Quito (N, ≤5%) and Cuenca (SSE, <5%) have very low probabilities of being affected by ash fallout. High ash clouds can move in different directions, compared to wind transport near the surface. Therefore, it is possible to detect ash clouds by remote sensing which, in Ecuador, is limited to the layers over the meteorological clouds, which move in a different direction than low wind; the latter produces ash fallout over regions in different directions compared to the detected ash clouds. In addition to the isomass/probability maps and detected ash clouds, forecasting is permanently required in Ecuador.
  • 1.7K
  • 21 Aug 2020
Topic Review
Glycosylation of Cancer Extracellular Vesicles
Glycans are major constituents of extracellular vesicles (EVs). Alterations in the glycosylation pathway are a common feature of cancer cells, which gives rise to de novo or increased synthesis of particular glycans. Therefore, glycans and glycoproteins have been widely used in the clinic as both stratification and prognosis cancer biomarkers. Interestingly, several of the tumor-associated glycans have already been identified in cancer EVs, which constitutes valuable sources of cancer biomarkers. Furthermore, glycans have also shown to play a role in EV protein sorting, uptake and tropism. Altogether, the EV glycan signatures hold tremendous potential to be applied into the clinical setting for both biomarker discovery and as therapeutic delivery systems.
  • 1.7K
  • 25 Jan 2021
Topic Review
Extroversion and Neuroticism at Work
Extroversion and Neuroticism. Many studies have linked personality traits to the way in which workers carry out their tasks, with the aim of optimizing employee performance. Understanding this relationship is very useful for both recruiting members of staff and assigning them to positions that best fit their personality. It is generally accepted that there are five principal traits or factors that can be used to catalog the structure of each individual personality.
  • 1.7K
  • 06 Feb 2021
Topic Review
Microplastics in Glaciers
Microplastic particles, as a second-phase material in ice, may contribute to the effect such particles have on the melting and rheological behaviour of glaciers, and thus influence the future meltwater contribution to the oceans and rising sea levels. Hence, it is of the utmost importance to map and understand the presence and dispersal of microplastics on a global scale. In this work, we identified microplastic particles in snow cores collected in a remote and pristine location on the Vatnajökull ice cap in Iceland. Utilising optical microscopy and µ-Raman spectroscopy, we visualised and identified microplastic particles of various sizes and materials. Our findings support that atmospheric transport of microplastic particles is one of the important pathways for microplastic pollution. 
  • 1.7K
  • 21 Apr 2021
Topic Review
Cardiac Involvement in Hereditary Hemochromatosis
Hereditary hemochromatosis (HH) is a genetic disease leading to excessive iron absorption, its accumulation, and oxidative stress induction causing different organ damage, including the heart. The process of cardiac involvement is slow and lasts for years. Cardiac pathology manifests as an impaired diastolic function and cardiac hypertrophy at first and as dilatative cardiomyopathy and heart failure with time. From the moment of heart failure appearance, the prognosis is poor. Therefore, it is crucial to prevent those lesions by upfront therapy at the preclinical phase of the disease. The most useful diagnostic tool for detecting cardiac involvement is echocardiography. However, during an early phase of the disease, when patients do not present severe abnormalities in serum iron parameters and severe symptoms of other organ involvement, heart damage may be overlooked due to the lack of evident signs of cardiac dysfunction. Considerable advancement in echocardiography, with particular attention to speckle tracking echocardiography, allows detecting discrete myocardial abnormalities and planning strategy for further clinical management before the occurrence of substantial heart damage. 
  • 1.7K
  • 19 Aug 2021
Topic Review
Applications of Magnetic Hydrogels
Magnetic hydrogels (MHGs) are a special class of hydrogel that contain at least one magnetic component in their composition. Generally, MNPs are dispersed in a polymer gel matrix to form MHGs. These hydrogels are special because they are prone to show fluctuations in their physical properties in the presence of an externally applied magnetic field.
  • 1.7K
  • 08 Dec 2021
Topic Review
Current Advances in Regeneration of Degenerated Articular Cartilage
Functional ability is the basis of healthy aging. Articular cartilage degeneration is amongst the most prevalent degenerative conditions that cause adverse impacts on the quality of life; moreover, it represents a key predisposing factor to osteoarthritis (OA). Both the poor capacity of articular cartilage for self-repair and the unsatisfactory outcomes of available clinical interventions make innovative tissue engineering a promising therapeutic strategy for articular cartilage repair. Significant progress was made in this field; however, a marked heterogeneity in the applied biomaterials, biofabrication, and assessments is nowadays evident by the huge number of research studies published to date. Accordingly, this entry assimilates the most recent advances in cell-based and cell-free tissue engineering of articular cartilage and also focuses on the assessments performed via various in vitro studies, ex vivo models, preclinical in vivo animal models, and clinical studies in order to provide a broad overview of the latest findings and clinical translation in the context of degenerated articular cartilage and OA.
  • 1.7K
  • 11 Jan 2022
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