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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.
  • 3.1K
  • 12 Oct 2020
Topic Review
Using CNSL for the Synthesis of Surfactants
Cashew Nut Shell Liquid (CNSL) is a promising non-edible renewable resource, directly extracted from the shell of the cashew nut. The interesting structure of CNSL and its components (cardanol, anacardic acid and cardol) lead to the synthesis of biobased surfactants. 
  • 3.1K
  • 10 Mar 2022
Topic Review
Tracked Locomotion Systems for Ground Mobile Robots
Service robotics is presently one of the fastest-growing technological fields. Nevertheless, while Automated Guided Vehicles (AGV) moving on flat and compact grounds are already commercially available and widely used to move components and products inside industrial buildings, the extensive application of ground mobile robots in environments that are unstructured or structured for humans is a promising challenge for the next years. The important application fields are agriculture, planetary exploration, reconnaissance in dangerous situations, such as radioactive or chemical contamination, homeland security and military operations, demining, intervention in case of terrorist attacks, and surveillance.
  • 3.1K
  • 26 Aug 2022
Topic Review
Gent (Hyperelastic Model)
The Gent hyperelastic material model is a phenomenological model of rubber elasticity that is based on the concept of limiting chain extensibility. In this model, the strain energy density function is designed such that it has a singularity when the first invariant of the left Cauchy-Green deformation tensor reaches a limiting value [math]\displaystyle{ I_m }[/math]. The strain energy density function for the Gent model is where [math]\displaystyle{ \mu }[/math] is the shear modulus and [math]\displaystyle{ J_m = I_m -3 }[/math]. In the limit where [math]\displaystyle{ I_m \rightarrow \infty }[/math], the Gent model reduces to the Neo-Hookean solid model. This can be seen by expressing the Gent model in the form A Taylor series expansion of [math]\displaystyle{ \ln\left[1 - (I_1-3)x\right] }[/math] around [math]\displaystyle{ x = 0 }[/math] and taking the limit as [math]\displaystyle{ x\rightarrow 0 }[/math] leads to which is the expression for the strain energy density of a Neo-Hookean solid. Several compressible versions of the Gent model have been designed. One such model has the form (the below strain energy function yields a non zero hydrostatic stress at no deformation, refer https://link.springer.com/article/10.1007/s10659-005-4408-x for compressible Gent models). where [math]\displaystyle{ J = \det(\boldsymbol{F}) }[/math], [math]\displaystyle{ \kappa }[/math] is the bulk modulus, and [math]\displaystyle{ \boldsymbol{F} }[/math] is the deformation gradient.
  • 3.1K
  • 21 Nov 2022
Topic Review Peer Reviewed
Disinformation Perception by Digital and Social Audiences: Threat Awareness, Decision-Making and Trust in Media Organizations
The effects of disinformation in the media and social networks have been extensively studied from the perspective of reception studies. However, the perception of this media phenomenon expressed by different types of audiences in distant geographic locations and with different media cultures has hardly been addressed by experts. This theoretical review study aims to analyze the relationship between the actual level of disinformation and the perception expressed by the audiences themselves. The results of the study reveal, firstly, that users of social networks and digital media do not perceive being surrounded by an excessively worrying volume of disinformation, a fact that contrasts with the data recorded, which are visibly higher. This situation reveals that the audience tends to normalize disinformation, which is intensively consumed on a daily basis and does not seem to worry the public in general terms, although some differences can be detected depending on variables such as gender, age or education. On the other hand, paradoxically, audiences visibly express rejection attitudes towards the channels that disseminate false information, with media outlets being the least trusted, despite recognizing that social networks are the place where more disinformation is generated and circulated at the same time.
  • 3.1K
  • 02 Nov 2023
Topic Review
Removal of Confederate Monuments and Memorials
For decades in the U.S., there have been isolated incidents of removal of Confederate monuments and memorials, although generally opposed in public opinion polls, and several U.S. States have passed laws over 115 years to hinder or prohibit further removals. In the wake of the Charleston church shooting in June 2015, several municipalities in the United States removed monuments and memorials on public property dedicated to the Confederate States of America. The momentum accelerated in August 2017 after the Unite the Right rally in Charlottesville, Virginia. The removals were driven by the belief that the monuments glorify white supremacy and memorialize a government whose founding principle was the perpetuation and expansion of slavery. Many of those who object to the removals, like President Trump, claim that the artifacts are part of the cultural heritage of the United States. Detractors claim that the vast majority of these Confederate monuments were built during the era of Jim Crow (1877–1954) and the Civil Rights Movement (1954–1968) not as memorials but as a means of intimidating African Americans and reaffirming white supremacy. The monuments have thus become highly politicized; according to Eleanor Harvey, a senior curator at the Smithsonian American Art Museum and a scholar of Civil War history: "If white nationalists and neo-Nazis are now claiming this as part of their heritage, they have essentially co-opted those images and those statues beyond any capacity to neutralize them again". Civil War historian James I. Robertson Jr. referred to the current climate to dismantle or destroy Confederate monuments as an "age of idiocy" and motivated by "elements hell-bent on tearing apart unity that generations of Americans have painfully constructed" and the monuments were not a "Jim Crow signal of defiance." In some Southern states, state law restricts or prohibits altogether the removal or alteration of public Confederate monuments. According to Stan Deaton, senior historian at the Georgia Historical Society, "These laws are the Old South imposing its moral and its political views on us forever more. This is what led to the Civil War, and it still divides us as a country. We have competing visions not only about the future but about the past." As Southern novelist William Faulkner famously put it, in the American South "the past is never dead. It's not even past."
  • 3.1K
  • 30 Nov 2022
Topic Review
Safe Mode (Spacecraft)
Safe mode is an operating mode of a modern unmanned spacecraft during which all non-essential systems are shut down and only essential functions such as thermal management, radio reception and attitude control are active. Safe mode is entered automatically upon the detection of a predefined operating condition or event that may indicate loss of control or damage to the spacecraft. Usually the trigger event is a system failure or detection of operating conditions considered dangerously out of the normal range. Cosmic rays penetrating spacecraft electrical systems can create false signals or commands and thus cause a trigger event. The central processor electronics are especially prone to such events. Another trigger is the lack of a received command within a given time window. Lack of received commands can be caused by hardware failures or mis-programming of the spacecraft, as in the case of the Viking 1 lander. The process of entering safe mode, sometimes referred to as safing, involves a number of immediate physical actions taken to prevent damage or complete loss. Power is removed from non-essential subsystems. Regaining attitude control, if lost, is the highest priority because it is necessary to maintain thermal balance and proper illumination of the solar panels. A tumbling or cartwheeling spacecraft can quickly roast, freeze or exhaust its battery power and be lost forever.
  • 3.1K
  • 02 Nov 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.
  • 3.1K
  • 04 Nov 2022
Topic Review
Permanent Magnet Synchronous Motor
The most common special features and demands of the PMSMs are described in the appearance of the motor’s failures caused by uncontrolled temperature rise. In addition, heat sources and energy losses, including copper loss, core loss versus motor speed, and output power, are analyzed. Various cooling strategies are listed and discussed. Scope of this review is to develop PMSM for a heavy duty green mobility with the smart light weight materials and with the enhanced cooling approaches.
  • 3.1K
  • 30 Mar 2021
Topic Review
Neonatal Early-Onset Sepsis
Neonatal early-onset sepsis (EOS) is defined as an invasive infection that occurs in the first 72 h of life. The incidence of EOS varies from 0.5–2 per 1000 live births in developed countries, up to 9.8 per 1000 live births in low resource settings, generating a high mortality rate, especially in extremely low birth weight neonates. Clinical signs are nonspecific, leading to a late diagnosis and high mortality. Currently, there are several markers used for sepsis evaluation, such as hematological indices, acute phase reactants, cytokines, which by themselves do not show acceptable sensitivity and specificity for the diagnosis of EOS in neonates. Newer and more selective markers have surfaced recently, such as presepsin and endocan, but they are currently only in the experimental research stages.
  • 3.1K
  • 28 Sep 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.
  • 3.1K
  • 17 Aug 2021
Topic Review
Spirulina and its Health Benefits
Spirulina is a kind of blue-green algae (BGA) that is multicellular, filamentous, and prokaryotic. It is also known as a cyanobacterium. It is classified within the phylum known as blue-green algae. Despite the fact that it includes a high concentration of nutrients, such as proteins, vitamins, minerals, and fatty acids—in particular, the necessary omega-3 fatty acids and omega-6 fatty acids—the percentage of total fat and cholesterol that can be found in these algae is substantially lower when compared to other food sources.
  • 3.1K
  • 20 Sep 2022
Topic Review
Secondary Marine Metabolites
Secondary marine metabolites are defined as molecules with a molecular weight ranging between 100 to 1000 Da and, unlike primary marine metabolites, are often found to be unique to an organism or a specific taxonomic group of the marine source. Other than marine macroorganisms such as algae, sponges, or corals, specifically marine fungi and bacteria have shown to produce novel secondary metabolites with unique as well as diverse chemical structures that may hold the key for developing novel drugs or drug leads. Secondary marine metabolites have been found in both prokaryotic and eukaryotic microorganisms, with unicellular bacteria (e.g., Bacillus sp., Pseudomonas sp.), eukaryotic fungi (e.g., Penicillium sp., Aspergillus sp.), filamentous actinomyces (e.g., Streptomyces sp.), and terrestrial plants being the most frequently studied and versatile producers. A potential clarification why organisms produce a high assortment of bioactive secondary marine metabolites is that these molecules furnish producers with a specific advantage against competing organisms and, furthermore, act as an adaptation to ecological conditions.
  • 3.1K
  • 30 Sep 2020
Topic Review Peer Reviewed
Human Resources Churning
The term churning is defined by a multifaceted approach and is quite a complex concept that has been gaining relevance in the field of human resources, due to the problematic loss of investment, originating from the voluntary exits of worker-associated costs. This phenomenon is a direct result of the rising competitive job market, causing employees to leave organizations and carry with them all the knowledge and experience acquired in the starting organization, an organization which invested in the development of its workers. Even though churning is aligned with human resource practices, it is considered a multifaceted concept because of the different contexts in which it interferes, such as economic context, per activity sector, clients, the type of organization, geographic location, etc. Although, despite its own complexity, churning is related to turnover; however, there are differences between these two concepts. While turnover is linked to the workers’ rotation within an organization, churning is mainly focused on the costs associated with voluntary exits from workers. It is simply linked to investment losses inside an organization, which has the main goal of creating mechanisms that allow the creation of awareness in organizations about the relevancy of action using strategic measurements of holding in order to minimize the churning rate, and in this way, reducing the unexpected costs, creating revenue, increasing proficiency, standing out in business activity, bettering nimbleness and expanding profits. This initial manuscript introduces the churning concept in human resources, the main causes of churning, as well as approaching how organizations take action in order to appease this event using literature, which lacks major advertising and given relevance to its pertinence in human resources. Through the analysis of the existing, this entry was guided with the objective of demystifying the subject of human resource churning.
  • 3.1K
  • 15 May 2023
Topic Review
CYP2E1
CYP2E1 is one of the fifty-seven cytochrome P450 genes in the human genome and is highly conserved. CYP2E1 is a unique P450 enzyme because its heme iron is constitutively in the high spin state, allowing direct reduction of, e.g., dioxygen, causing the formation of a variety of reactive oxygen species and reduction of xenobiotics to toxic products.
  • 3.1K
  • 02 Sep 2021
Topic Review
The Flavonoid Biosynthesis Network in Plants
Flavonoids have long been a major focus of research into secondary metabolism. We present a systematic summary of what is known of the flavonoid biosynthetic pathway in plants, presenting a model of flavonoid biosynthesis that includes eight branches (stilbene, aurone, flavone, isoflavone, flavonol, phlobaphene, proanthocyanidin, and anthocyanin biosynthesis) and four important intermediate metabolites (chalcone, flavanone, dihydroflavonol, and leucoanthocyanidin). 
  • 3.1K
  • 23 Dec 2021
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.
  • 3.1K
  • 27 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. 
  • 3.1K
  • 14 Sep 2021
Topic Review
Botulinum Neurotoxin Injection for Wrinkles in Nose Region
As wrinkle removal using BoNT is being performed more often, the adverse effects, such as paralysis of the nearby muscles, diplopia, ptosis, and samurai eyebrows have been reported. When treating wrinkles with BoNT in the nasal region, significant problems, such as diplopia may result from unintended paralysis of the rectus inferior or medialis. To prevent these side effects, the injection should be administered at an anatomically accurate location of the targeting muscle, and the initial treatment should be at a reduced dosage.
  • 3.1K
  • 18 May 2022
Topic Review
Negative-Sense Single-Stranded RNA Viral Factories
Liquid–liquid phase separation (LLPS) represents a major physiochemical principle to organize intracellular membrane-less structures. Studies with non-segmented negative-sense (NNS) RNA viruses have uncovered a key role of LLPS in the formation of viral inclusion bodies (IBs), sites of viral protein concentration in the cytoplasm of infected cells. These studies further reveal the structural and functional complexity of viral IB factories as liquid-like organelles and sites of viral replication.
  • 3.1K
  • 29 Jan 2021
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