Log in/Sign up
Arts & Humanities
Biology & Life Sciences
Business & Economics
Chemistry & Materials Science
Computer Science & Mathematics
Environmental & Earth Sciences
Medicine & Pharmacology
Public Health & Healthcare
Bisphenols (BPs), and especially bisphenol A (BPA), are known endocrine disruptors (EDCs), capable of interfering with estrogen and androgen activities, as well as being suspected of other health outcomes.
28 Oct 2020
Blood-Brain Barrier: Functionalised Chitosan
The major impediment to the delivery of therapeutics to the brain is the presence of the blood-brain barrier (BBB). The BBB allows for the entrance of essential nutrients while excluding harmful substances, including most therapeutic agents; hence, brain disorders, especially tumors, are very difficult to treat. Chitosan is a well-researched polymer that offers advantageous biological and chemical properties, such as mucoadhesion and ease of functionalization. Chitosan-based nanocarriers (CsNCs) establish ionic interactions with the endothelial cells, facilitating the crossing of drugs through the BBB by adsorptive mediated transcytosis. This process is further enhanced by modifications of the structure of chitosan, owing to the presence of reactive amino and hydroxyl groups. Finally, by permanently binding ligands or molecules, such as antibodies or lipids, CsNCs have shown a boosted passage through the BBB, in both in vivo and in vitro studies which will be discussed in this review.
21 Nov 2020
Congenital Malformations in Sea Turtles
Congenital malformations can lead to embryonic mortality in many species, and sea turtles are no exception. Genetic and/or environmental alterations occur during early development in the embryo, and may produce aberrant phenotypes, many of which are incompatible with life. Causes of malformations are multifactorial; genetic factors may include mutations, chromosomal aberrations, and inbreeding effects, whereas non-genetic factors may include nutrition, hyperthermia, low moisture, radiation, and contamination. It is possible to monitor and control some of these factors (such as temperature and humidity) in nesting beaches, and toxic compounds in feeding areas, which can be transferred to the embryo through their lipophilic properties.
22 Feb 2021
Mechanobiology of Chondrocytes
This entry is associated with a review article, published in MDPI Applied Sciences on 23 April 2020, about the current knowledge on the mechanical stimulation of mesenchymal stem cells for cartilage regeneration. Loading stresses, physiologically experienced by chondrocytes, regulate the production of glycosaminoglycan and collagen, as well as promote and preserve cell viability. Therefore, there is a rising interest in the development of devices that impose mechanical stimuli, such as compression and shear stress, on mesenchymal stem cells. The mentioned review will analyze the dynamics within the joint, the physiological stimuli experienced by the chondrocytes, and how the biomechanical stimulation can be applied to a stem cell culture in order to induce chondrogenesis. In addition to that, paper lists some of the current applications in the field.
29 Oct 2020
Spinal-Deformities and Advancement in Corrective-Orthoses
Spinal deformity is an abnormality in the spinal curves and can seriously affect the activities of daily life. The conventional way to treat spinal deformities, such as scoliosis, kyphosis, and spondylolisthesis, is to use spinal orthoses (braces). Braces have been used for centuries to apply corrective forces to the spine to treat spinal deformities or to stabilize the spine during postoperative rehabilitation. Braces have not modernized with advancements in technology, and very few braces are equipped with smart sensory design and active actuation. There is a need to enable the orthotists, ergonomics practitioners, and developers to incorporate new technologies into the passive field of bracing.
30 Jan 2021
Bradoriids and the Cambrian Diversification
Bradoriids, among the earliest arthropods to appear in the fossil record, are extinct, ostracod-like bivalved forms that ranged from the early Cambrian to the Middle Ordovician. Bradoriids are notable for having appeared in the Cambrian fossil record before the earliest trilobites, and considering their rapid ascent to high genus-level diversity, provide key data for our understanding of the evolutionary dynamics of the Cambrian Explosion. This paper presents a broad review of bradoriid paleobiology.
29 Oct 2020
Forensic Facial Comparison
Forensic facial comparison is a human observer-based technique employed in forensic facial identification. Facial identification falls under the broader discipline of facial imaging, and involves the use of visual facial information to assist in person identification. Through the analysis of photographic or video evidence (e.g., CCTV), forensic facial identification is routinely utilized to associate persons of interest to criminal activity in a judicial context. The recommended approach to forensic facial comparison is facial examination by morphological analysis, whereby a facial feature list is used to analyze, compare, and evaluate visible facial features between a target image and a potential matching image. This process is then validated by a second analyst. Forensic facial comparison, and its broader discipline of facial identification, should not be confused with automated facial recognition technology or the innate psychological process of facial recognition.
13 Dec 2021
Surfactant and the Glycocalyx
Gas exchange in the lung takes place via the air-blood barrier in the septal walls of alveoli. The tissue elements that oxygen molecules have to cross are the alveolar epithelium, the interstitium and the capillary endothelium. The epithelium that lines the alveolar surface is covered by a thin and continuous liquid lining layer. Pulmonary surfactant acts at this air-liquid interface. By virtue of its biophysical and immunomodulatory functions, surfactant keeps alveoli open, dry and clean. What needs to be added to this picture is the glycocalyx of the alveolar epithelium. Here, we briefly review what is known about this glycocalyx and how it can be visualized using electron microscopy. The application of colloidal thorium dioxide as a staining agent reveals differences in the staining pattern between type I and type II alveolar epithelial cells and shows close associations of the glycocalyx with intraalveolar surfactant subtypes such as tubular myelin. These morphological findings indicate that specific spatial interactions between components of the surfactant system and those of the alveolar epithelial glycocalyx exist which may contribute to the maintenance of alveolar homeostasis, in particular to alveolar micromechanics, to the functional integrity of the air-blood barrier, to the regulation of the thickness and viscosity of the alveolar lining layer, and to the defence against inhaled pathogens. Exploring the alveolar epithelial glycocalyx in conjunction with the surfactant system opens novel physiological perspectives of potential clinical relevance for future research.
03 May 2021
Adhesion Protein Sialylation
The importance of adhesion protein sialylation was recognized by studying the changes of adhesion behavior of human tissue cells exposed in vitro to microgravity. Proteins involved in cell-cell or cell-extracellular matrix adhesion were investigated by retrieving and evaluation of information about sialylation of cell adhesion molecules detected by omics studies on cells, which change their adhesion behavior when exposed to microgravity. Using a knowledge graph created from experimental omics data and semantic searches across several reference databases, sialylation of adhesion proteins glycosylated at their extracellular domains and their impact in cellular processes were studied. This way, experimental omics data networked with the current knowledge about binding of sialic acids to cell adhesion proteins, its regulation and interactions in-between those proteins provided insights in the mechanisms behind experimental findings suggesting that balancing sialylation against de-sialylation of the terminal ends of the adhesion proteins’ glycans influences the binding activity of adhesion proteins, the interaction of cells and their aggregation. This shed light on the transition from the cells’ growth in a monolayer to spheroid formation observed in microgravity mirroring cell migration and cancer metastasis in vivo.
30 Oct 2020
Documented Skeletal Collections in the United States
In the US, documented skeletal collections are a collective of human skeletons that originated (mostly) from body donations, human taphonomy facilities (e.g., the William M. Bass Donated Skeletal Collection), and anatomical dissections (e.g., Robert J. Terry Anatomical Collection). These collections are a major asset in the testing and development of methods used to infer the biological profile of human remains.
19 Apr 2022
Featured Entry Collections
Encyclopedia of Social Sciences
Encyclopedia of ZEMCH Research and Development
Encyclopedia of Engineering
Encyclopedia of Piezoelectrics
Log in/Sign up
Terms and Conditions
Browse our user manual, common Q&A, author guidelines, etc.
Rate your experience
Let us know your experience and what we could improve.
Report an error
Is something wrong? Please let us know!
Other feedback you would like to report.
Did you find what you were looking for?
Do you agree to share your valuable feedback publicly on
Yes, I agree. Encyclopedia can post it.
No, I do not agree. I would not like to post my testimonial.
Upload a screenshot
(Max file size 2MB)