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Topic Review
E-Bike Sharing System
Recent data on conventional bike and/or electric bike (e-bike) sharing systems reveal that more than 2900 systems are operating in cities worldwide, indicating the increased adoption of this alternative mode of transportation. Addressing the existing gap in the literature regarding the deployment of e-bike sharing systems (e-BSSs) in particular, this paper reviews their spatio-temporal characteristics, and attempts to (a) map the worldwide distribution of e-BSSs, (b) identify temporal trends in terms of annual growth/expansion of e-BSS deployment worldwide and (c) explore the spatial characteristics of the recorded growth, in terms of adoption on a country scale, population coverage and type of system/initial fleet sizes. To that end, it examines the patterns identified from the global to the country level, based on data collected from an online source of BSS information worldwide. A comparative analysis is performed with a focus on Europe, North America and Asia, providing insights on the growth rate of the specific bikesharing market segment. Although the dockless e-BSS has been only within three years of competition with station-based implementations, it shows a rapid integration to the overall technology diffusion trend, while it is more established in Asia and North America in comparison with Europe and launches with larger fleet sizes.
  • 3.0K
  • 27 Oct 2020
Topic Review
Bisphenols
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.
  • 3.0K
  • 28 Oct 2020
Topic Review
Social Networks in Health-Care Industry
The application of social networks in the health domain has become increasingly prevalent. They are web-based technologies which bring together a group of people and health-care providers having in common health-related interests, who share text, image, video and audio contents and interact with each other. This explains the increasing amount of attention paid to this topic by researchers who have investigated a variety of issues dealing with the specific applications in the health-care industry. The aim of this study is to systematize this fragmented body of literature, and provide a comprehensive and multi-level overview of the studies that has been carried out to date on social network uses in healthcare, taking into account the great level of diversity that characterizes this industry. To this end, we conduct a scoping review enabling to identify the major research streams, whose aggregate knowledge are discussed according to three levels of analysis that reflect the viewpoints of the major actors using social networks for health-care purposes, i.e., governments, health-care providers (including health-care organizations and professionals) and social networks’ users (including ill patients and general public). We conclude by proposing directions for future research. 
  • 3.0K
  • 14 Sep 2021
Topic Review
Buddhist Tantras
The Buddhist Tantras are a varied group of Indian and Tibetan texts which outline unique views and practices of the Buddhist tantra religious systems.
  • 3.0K
  • 14 Oct 2022
Topic Review
African American Studies
African American studies (alternately Black studies, or Africana studies, among other terms) is an interdisciplinary academic field that is primarily devoted to the study of the history, culture, and politics of black people from the United States . African American studies are a sub-field of African diaspora studies and Africana studies, the study of the people of African origin worldwide. The field has been defined in different ways, but taken broadly, it not only studies African slave descendants but also any community of the African diaspora linked to the Americas. The field includes scholars of African American (as well as Caribbean, African, and Afro-European) literature, history, politics, and religion as well as those from disciplines such as sociology, anthropology, cultural studies, psychology, education, and many other disciplines within the humanities and social sciences. And, increasingly, African American Studies departments are hiring and partnering with STEM scholars. Intensive academic efforts to reconstruct African American history began in the late 19th century (W. E. B. Du Bois, The Suppression of the African Slave-trade to the United States of America, 1896). Among the pioneers in the first half of the 20th century were Carter G. Woodson, Herbert Aptheker, Melville Herskovits, and Lorenzo Dow Turner. Programs and departments of African American Studies were first created in the 1960s and 1970s as a result of inter-ethnic student and faculty activism at many universities, sparked by a five-month strike for black studies at San Francisco State. In February 1968, San Francisco State hired sociologist Nathan Hare to coordinate the first black studies program and write a proposal for the first Department of Black Studies; the department was created in September 1968 and gained official status at the end of the five-months strike in the spring of 1969. The creation of programs and departments in black studies was a common demand of protests and sit-ins by minority students and their allies, who felt that their cultures and interests were underserved by the traditional academic structures. Black studies is a systematic way of studying black people in the world – such as their history, culture, sociology, policies, experience, issues and religion. It is a study of the black experience and the effect of society on them and their effect within society. This study aims to, among other things, help eradicate many racial stereotypes. Black studies implements history, family structure, social and economic pressures, stereotypes, and gender relationships.
  • 3.0K
  • 04 Nov 2022
Topic Review
Short Text Clustering Algorithms
Short text clustering (STC) has become a critical task for automatically grouping various unlabelled texts into meaningful clusters. STC is a necessary step in many applications, including Twitter personalization, sentiment analysis, spam filtering, customer reviews and many other social network-related applications.
  • 3.0K
  • 18 Jan 2023
Topic Review
Ventilation-Perfusion Mismatch in the Acute Respiratory Distress Syndrome
Acute respiratory distress syndrome (ARDS) is a heterogenous condition that is characterized by the development of inflammatory pulmonary edema and life-threatening hypoxemia, and it accounts for nearly 25% of patients who require mechanical ventilation. Acute respiratory distress syndrome (ARDS) remains an important clinical challenge with a mortality rate of 35–45%. It is being increasingly demonstrated that the improvement of outcomes requires a tailored, individualized approach to therapy, guided by a detailed understanding of each patient’s pathophysiology. In patients with ARDS, disturbances in the physiological matching of alveolar ventilation (V) and pulmonary perfusion (Q) (V/Q mismatch) are a hallmark derangement. The perfusion of collapsed or consolidated lung units gives rise to intrapulmonary shunting and arterial hypoxemia, whereas the ventilation of non-perfused lung zones increases physiological dead-space, which potentially necessitates increased ventilation to avoid hypercapnia.
  • 3.0K
  • 12 Jan 2023
Topic Review
Homogeneity
In physics, a homogeneous material or system has the same properties at every point; it is uniform without irregularities. A uniform electric field (which has the same strength and the same direction at each point) would be compatible with homogeneity (all points experience the same physics). A material constructed with different constituents can be described as effectively homogeneous in the electromagnetic materials domain, when interacting with a directed radiation field (light, microwave frequencies, etc.). Mathematically, homogeneity has the connotation of invariance, as all components of the equation have the same degree of value whether or not each of these components are scaled to different values, for example, by multiplication or addition. Cumulative distribution fits this description. "The state of having identical cumulative distribution function or values".
  • 3.0K
  • 15 Nov 2022
Topic Review
Major Losses in Wheat Combine Harvester Operation
Wheat harvesting is one of the most important links in the whole wheat production process. In China, the wheat planting areas are wide, and the patterns are diversified. In addition, the problem of harvest losses caused by the numerous brands and low performance of domestic combine harvesters has always existed. Any losses during harvesting will result in less income for the farmers.
  • 3.0K
  • 28 Nov 2022
Topic Review
Cyanobacteria: Model Microorganisms and Beyond
Cyanobacteria, also formerly called “blue-green algae”, are photosynthetic prokaryotes with ~3500 million years of existence on the planet earth. They live in a diverse range of environments, from freshwater and marine to terrestrial ecosystems. Cyanobacteria can tolerate and live in the most extreme habitats including geothermal habitats, frozen systems, and hypersaline environments.
  • 3.0K
  • 14 Apr 2022
Topic Review
T Lymphocyte
Exosomes are extracellular vesicles (EV) of endosomal origin (multivesicular bodies, MVB) constitutively released by many different eukaryotic cells by fusion of MVB to the plasma membrane. However, inducible exosome secretion controlled by cell surface receptors is restricted to very few cell types and a limited number of cell surface receptors. Among these, exosome secretion is induced in T lymphocytes and B lymphocytes when stimulated at the immune synapse (IS) via T-cell receptor (TCR) and B-cell receptor (BCR), respectively. IS formation by T and B lymphocytes constitutes a crucial event involved in antigen-specific, cellular and humoral immune responses. Upon IS formation by T and B lymphocytes with antigen-presenting cells (APC) the convergence of MVB towards the microtubule organization center (MTOC), and MTOC polarization to the IS, are involved in polarized exosome secretion at the synaptic cleft. This specialized mechanism provides the immune system with a finely-tuned strategy to increase the specificity and efficiency of crucial secretory effector functions of B and T lymphocytes. Since inducible exosome secretion by antigen-receptors is a critical and unique feature of the immune system this entry considers the study of the traffic events leading to polarized exosome secretion at the IS and some of their biological consequences.
  • 3.0K
  • 29 Oct 2020
Topic Review
Climate Change Impacts on Sunflower Plants
Elevated concentrations of atmospheric carbon dioxide (CO2) and increased temperatures, carbon and nitrogen metabolism will  affect the plant’s oxidative state in sunflower (Helianthus annus L.) plants
  • 3.0K
  • 24 Jan 2022
Topic Review
Aspartate in Cell Proliferation and Survival
Aspartate is a precursor for nucleotide synthesis and  is indispensable for cell proliferation. Moreover, the malate–aspartate shuttle plays a key role in redox balance, and a deficit in aspartate can lead to oxidative stress. It is now recognized that aspartate biosynthesis is largely governed by mitochondrial metabolism, including respiration and glutaminolysis in cancer cells. Therefore, under conditions that suppress mitochondrial metabolism, including mutations, hypoxia, or chemical inhibitors, aspartate can become a limiting factor for tumor growth and cancer cell survival.
  • 3.0K
  • 15 Jul 2022
Topic Review
Characteristics of Vitamin E
Vitamin E is a fat-soluble organic micronutrient that helps to preserve human health. Its main function is likely that of a radical scavenger protecting biological membranes from lipid peroxidation. Vegetable oils, such as wheat germ, sunflower, corn germ, soybean, and rapeseed, are the primary dietary source of vitamin E for humans. It is also found in some nuts, fruits, and vegetables, such as almonds, avocados, spinach, and kale.
  • 3.0K
  • 16 Sep 2022
Topic Review
Agent-Based Models and Simulations Tools
Agent-based models (ABMs) are one of the most effective and successful methods for analyzing real-world complex systems by investigating how modeling interactions on the individual level (i.e., micro-level) leads to the understanding of emergent phenomena on the system level (i.e., macro-level). ABMs represent an interdisciplinary approach to examining complex systems, and the heterogeneous background of ABM users demands comprehensive, easy-to-use, and efficient environments to develop ABM simulations. Many tools, frameworks, and libraries exist, each with its characteristics and objectives.
  • 3.0K
  • 01 Feb 2023
Topic Review
Applications of Lignin in Wood
Lignin is the most abundant aromatic polymer in nature and the second most abundant biomass on earth. In paper production and other processes, lignin is obtained as a side product and mainly used energetically. The use of lignin in wood adhesives or for wood modification has received a lot of scientific attention.
  • 3.0K
  • 25 May 2021
Topic Review
Starch–Mucilage Composite Films
Generally, starch is an edible carbohydrate complex, composed of a linear polymer, amylose (a linear molecule with few branches), and amylopectin (branched-chain molecule). Therefore, the presence of amylose in large quantities provides excellent strength while a high level of amylopectin is responsible for the reduction of the tensile strength during the production of a film. However, starch-based films have limitations in their ability to bear various environmental factors such as temperature, pressure, and natural gases during the handling due to their low strength, flexibility, rigidity, and high hydrophilic nature. To overcome this issue, the combination of starch and mucilage can be used as a binary polymer alternative to improve the mechanical properties of the packaging film. Additionally, the addition of several biopolymers such as cellulose, gum, and gelatin into a starch blend can change the network formation in the film matrix, improving the physicochemical and biological properties of the film. Moreover, mucilage is a water-soluble edible polysaccharide, extensively used in the food industry due to its excellent functional properties (antimicrobial, antioxidant, water-holding, oil holding, and foaming capacity), and diverse industrial applications such as thickening agent, binding agent, emulsifying agent, and suspending agent. Mucilage has a great potential to produce a stable polymeric network that confines the starch granules, which delay the release of amylose in resulting the improvement of the mechanical property of films.
  • 3.0K
  • 17 Aug 2021
Topic Review
Fluid Reaction Models
In the fluidized bed system, the performance of the reactor is affected by the hydrodynamic behaviors of the reactor in that fluid dynamics affects both heat and mass transfer.
  • 3.0K
  • 28 Jul 2021
Topic Review
CRISPR Therapeutics
The Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) genome editing system has been the focus of intense research in the last decade due to its superior ability to desirably target and edit DNA sequences. The applicability of the CRISPR-Cas system to in vivo genome editing has acquired substantial credit for a future in vivo gene-based therapeutic. Challenges such as targeting the wrong tissue, undesirable genetic mutations, or immunogenic responses, need to be tackled before CRISPR-Cas systems can be translated for clinical use. Hence, there is an evident gap in the field for a strategy to enhance the specificity of delivery of CRISPR-Cas gene editing systems for in vivo applications. Current approaches using viral vectors do not address these main challenges and, therefore, strategies to develop non-viral delivery systems are being explored. Peptide-based systems represent an attractive approach to developing gene-based therapeutics due to their specificity of targeting, scale-up potential, lack of an immunogenic response and resistance to proteolysis. In this review, we discuss the most recent efforts towards novel non-viral delivery systems, focusing on strategies and mechanisms of peptide-based delivery systems, that can specifically deliver CRISPR components to different cell types for therapeutic and research purposes.
  • 3.0K
  • 12 Oct 2020
Topic Review
The NifA–NifL System for Nitrogen Fixation
Nitrogen–fixing bacteria execute biological nitrogen fixation through nitrogenase, converting inert dinitrogen (N2) in the atmosphere into bioavailable nitrogen. Elaborating the molecular mechanisms of orderly and efficient biological nitrogen fixation and applying them to agricultural production can alleviate the “nitrogen problem”. Azotobacter vinelandii is a well–established model bacterium for studying nitrogen fixation, utilizing nitrogenase encoded by the nif gene cluster to fix nitrogen. In Azotobacter vinelandii, the NifA–NifL system fine–tunes the nif gene cluster transcription by sensing the redox signals and energy status, then modulating nitrogen fixation. 
  • 3.0K
  • 06 Feb 2023
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