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Topic Review
Digital Subtraction Angiography Technical in Lower Limb Arteries
Cardiovascular diseases represent one of the most frequent diseases worldwide; among these, lower limb ischemia is a threatening condition, which can lead to permanent disability if not promptly and correctly diagnosed and treated. A patient’s clinical evaluation and diagnostic imaging (e.g., color-Doppler ultrasound, computed tomography angiography (CTA), and magnetic resonance imaging (MRI)) are mandatory to carefully assess arterial lesion extension and severity. Digital subtraction angiography (DSA) is a minimally invasive technique that represents the gold standard for percutaneous revascularization treatment of symptomatic patients who are refractory to medical management.
  • 1.9K
  • 21 Nov 2022
Topic Review
3D Printing of Pure Copper Functional Structures
The 3D printing of pure copper to sufficiently high densities has finally taken off, due to the emergence of commercial-grade printers which are now equipped with 1 kW high-power lasers or short-wavelength lasers.
  • 1.9K
  • 24 Oct 2023
Topic Review
Celiac Disease
Celiac disease (CD) is a chronic enteropathy that develops in genetically susceptible individuals after the ingestion of gluten. There has been a substantial increase in CD prevalence in the last 50 years, and it is now estimated that this disease affects approximately 1% of the population in the Western world. In the large majority of cases, CD is a benign disease, characterized by the complete resolution of symptoms and a normal life expectancy after the onset of a gluten-free diet (GFD). However, failure to adhere to a strict GFD bears the risk of adverse events and increases mortality. A considerable number of studies have considered the possible association between CD and neoplasms. In particular, an increased risk of malignancies, such as cancers of the gastrointestinal tract and intestinal lymphomas, has been reported. In this review, we summarize and discuss the current evidence on the possible association between CD and cancer.
  • 1.9K
  • 27 Oct 2020
Topic Review
Atherosclerosis
Macrophages are key target immune cells in atherosclerosis. A hallmark of atherosclerosis is the accumulation of pro-inflammatory macrophages in coronary arteries that respond to pro-atherogenic stimuli and failure of digesting lipids that contribute to foam cell formation in atherosclerotic plaques.
  • 1.9K
  • 29 Jan 2022
Topic Review
Carbon Dots
Carbon dots (CDs) are part of the nanocarbon family including quasi-spherical nanoparticles with sizes around 10 nm. They consist of amorphous and crystalline parts, mainly composed of carbon with a fringe spacing of 0.34 nm, which corresponds to the (002) interlayer spacing of graphite. Since their first discovery in 2006, CDs have gained ever-increasing attention due to their fascinating properties like distinctive optical behaviour, tunable emission, different functional groups, good biocompatibility, chemical and photo-stability, low toxicity, and low-cost production. More importantly, CDs properties can be changed by controlling their size, shape, and heteroatom doping and by modifying the surfaces. They are considered promising Green alternatives to traditional fluorescent dyes and have been proposed for different optoelectronic applications such as sensing, bioimaging, fingerprint detection, gene delivery, solar cells, or printing inks
  • 1.9K
  • 08 Mar 2021
Topic Review
Nucleosides and Nucleotides
Nucleotides fulfill many essential functions in plants. Compared to non-plant systems, these hydrophilic metabolites have not been adequately investigated in plants, especially the less abundant nucleotide species such as deoxyribonucleotides and modified or damaged nucleotides. Until recently, this was mainly due to a lack of adequate methods for in-depth analysis of nucleotides and nucleosides in plants.
  • 1.9K
  • 16 Apr 2021
Topic Review
AI-Based Wormhole Attack Detection Techniques
The popularity of wireless sensor networks for establishing different communication systems is increasing daily. A wireless network consists of sensors prone to various security threats. These sensor nodes make a wireless network vulnerable to denial-of-service attacks. One of them is a wormhole attack that uses a low latency link between two malicious sensor nodes and affects the routing paths of the entire network. This attack is brutal as it is resistant to many cryptographic schemes and hard to observe within the network. 
  • 1.9K
  • 12 Aug 2022
Topic Review
BLAST
In bioinformatics, BLAST (basic local alignment search tool) is an algorithm for comparing primary biological sequence information, such as the amino-acid sequences of proteins or the nucleotides of DNA and/or RNA sequences. A BLAST search enables a researcher to compare a query sequence with a library or database of sequences, and identify library sequences that resemble the query sequence above a certain threshold. Different types of BLASTs are available according to the query sequences. For example, following the discovery of a previously unknown gene in the mouse, a scientist will typically perform a BLAST search of the human genome to see if humans carry a similar gene; BLAST will identify sequences in the human genome that resemble the mouse gene based on similarity of sequence. The BLAST algorithm and program were designed by Stephen Altschul, Warren Gish, Webb Miller, Eugene Myers, and David J. Lipman at the National Institutes of Health and was published in the Journal of Molecular Biology in 1990 and cited over 50,000 times.
  • 1.9K
  • 17 Oct 2022
Topic Review
Photocatalysis for Water Splitting Capabilities
Water could be used as the main source of hydrogen production. By definition, the dissociation of the water molecules into their constituents (hydrogen and oxygen) is known as water splitting. Rapid population growth and ever-increasing energy consumption have resulted in increased environmental pollution and energy demands. Accordingly, studies and research on innovative and efficient ways of wastewater clean-up and exploiting eco-friendly and renewable energy sources such as sunlight have become a necessity. 
  • 1.9K
  • 07 Nov 2022
Topic Review
Mobile Web
The mobile web, also known as mobile internet, refers to browser-based Internet services accessed from handheld mobile devices, such as smartphones or feature phones, through a mobile or other wireless network. Traditionally, the World Wide Web has been accessed via fixed-line services on laptops and desktop computers. However, the web is now more accessible by portable and wireless devices. An early 2010 ITU (International Telecommunication Union) report said that with current growth rates, web access by people on the go – via laptops and smart mobile devices – is likely to exceed web access from desktop computers within the next five years. In January 2014, mobile internet use exceeded desktop use in the United States. The shift to mobile web access has accelerated since 2007 with the rise of larger multitouch smartphones, and since 2010 with the rise of multitouch tablet computers. Both platforms provide better Internet access, screens, and mobile browsers, or application-based user web experiences, than previous generations of mobile devices. Web designers may work separately on such pages, or pages may be automatically converted, as in Mobile Wikipedia. Faster speeds, smaller, feature-rich devices, and a multitude of applications continue to drive explosive growth for mobile internet traffic. The 2017 Virtual Network Index (VNI) report produced by Cisco Systems forecasts that by 2021, there will be 5.5 billion global mobile users (up from 4.9 billion in 2016). Additionally, the same 2017 VNI report forecasts that average access speeds will increase by roughly 3 times from 6.8 Mbit/s to 20 Mbit/s in that same time span with video comprising the bulk of the traffic (78%). The distinction between mobile web applications and native applications is anticipated to become increasingly blurred, as mobile browsers gain direct access to the hardware of mobile devices (including accelerometers and GPS chips), and the speed and abilities of browser-based applications improve. Persistent storage and access to sophisticated user interface graphics functions may further reduce the need for the development of platform-specific native applications. The mobile web has also been called Web 3.0, drawing parallels to the changes users were experiencing as Web 2.0 websites proliferated. Mobile web access today still suffers from interoperability and usability problems. Interoperability issues stem from the platform fragmentation of mobile devices, mobile operating systems, and browsers. Usability problems are centered on the small physical size of the mobile phone form factors (limits on display resolution and user input/operating). Despite these shortcomings, many mobile developers choose to create apps using mobile web. A June 2011 research on mobile development found mobile web the third most used platform, trailing Android and iOS. In an article in Communications of the ACM in April 2013, Web technologist Nicholas C. Zakas, noted that mobile phones in use in 2013 were more powerful than Apollo 11's 70 lb (32 kg) Apollo Guidance Computer used in the July 1969 lunar landing. However, in spite of their power, in 2013, mobile devices still suffer from web performance with slow connections similar to the 1996 stage of web development. Mobile devices with slower download request/response times, the latency of over-the-air data transmission, with "high-latency connections, slower CPUs, and less memory" force developers to rethink web applications created for desktops with "wired connections, fast CPUs, and almost endless memory." The mobile web was first popularized by a silicon valley company known as Unwired Planet. In 1997, Unwired Planet, Nokia, Ericsson, and Motorola started the WAP Forum to create and harmonize the standards to ease the transition to bandwidth networks and small display devices. The WAP standard was built on a three-layer, middleware architecture that fueled the early growth of the mobile web, but was made virtually irrelevant with faster networks, larger displays, and advanced smartphones based on Apple's iOS and Google's Android software.
  • 1.9K
  • 09 Nov 2022
Topic Review
Lens (Anatomy)
The lens, or crystalline lens is a transparent biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. By changing shape, it functions to change the focal length of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina. This adjustment of the lens is known as accommodation (see also below). Accommodation is similar to the focusing of a photographic camera via movement of its lenses. The lens is flatter on its anterior side than on its posterior side. In humans, the refractive power of the lens in its natural environment is approximately 18 dioptres, roughly one-third of the eye's total power.
  • 1.9K
  • 21 Nov 2022
Topic Review
Global Climate Coalition
The Global Climate Coalition (GCC) (1989–2001) was an international lobbyist group of businesses that opposed action to reduce greenhouse gas emissions and publicly challenged the science behind global warming. The GCC was the largest industry group active in climate policy and the most prominent industry advocate in international climate negotiations. The GCC was involved in opposition to the Kyoto Protocol, and played a role in blocking ratification by the United States. The coalition knew it could not deny the scientific consensus, but sought to sow doubt over the scientific consensus on climate change and create manufactured controversy. The GCC dissolved in 2001 after membership declined in the face of improved understanding of the role of greenhouse gases in climate change and of public criticism.
  • 1.9K
  • 24 Nov 2022
Topic Review
Spinophorosaurus
Spinophorosaurus is a genus of sauropod dinosaur that lived in what is now Niger during the Middle Jurassic period. The first two specimens were excavated in the 2000s by German and Spanish teams under difficult conditions. The skeletons were brought to Europe and digitally replicated, making Spinophorosaurus the first sauropod to have its skeleton 3D printed, and were to be returned to Niger in the future. Together, the two specimens represented most of the skeleton of the genus, and one of the most completely known basal sauropods of its time and place. The first skeleton was made the holotype specimen of the new genus and species Spinophorosaurus nigerensis in 2009; the generic name ("spine-bearing lizard") refers to what was initially thought to be spiked osteoderms, and the specific name (Niger and -ensis) refers to where it was found. A juvenile sauropod from the same area was later assigned to the genus. The subadult holotype specimen is estimated to have been around 13 m (43 ft) in length, whereas the paratype was about 14 m (46 ft) long. The shoulder height reached by these individuals was estimated at around 4 m (13 ft), and the weight at about 7 metric tons (7.7 short tons). The braincase was short, deep, and broad, and the neuroanatomy was in some ways intermediate between that of basal sauropodomorphs and the more derived neosauropods. The teeth were spatulate (spoon shaped) and had large spaced denticles at the top of the crown, an ancestral feature in sauropods. The neck of Spinophorosaurus is one of the most completely known among sauropods, containing 13 vertebrae. The dorsal vertebrae had multiple small air-filled internal chambers, a feature typical of later more-derived sauropods. The tail was powered by strong musculature and had a rear section that was rather rigid due to long and overlapping chevron bones. Bones originally thought to be osteoderms bearing spikes placed on the tail tip were later suggested to be clavicles. Spinophorosaurus has been classified as either a very basal sauropod, or inside Eusauropoda, a more derived group. The anatomy, age, and location of specimens indicate that important developments in sauropod evolution may have occurred in North Africa, possibly controlled by climatic zones and plant biogeography. Features of the vestibular apparatus suggest that vision and coordinated eye, head, and neck movements were important in Spinophorosaurus. 3D models of the skeleton have been used to test its range of motion. One study suggests it may have been a high browser, and another examined possible mating postures. Sutures between the neural arches with the centra of the vertebrae were more complex in the front part of the trunk of Spinophorosaurus, since stresses were probably greatest in that region. Spinophorosaurus is known from the Irhazer Shale, a geological formation thought to be Middle Jurassic in age. It was formed by deposits from rivers and lakes in a great river-valley system.
  • 1.9K
  • 24 Nov 2022
Topic Review
Polymer Waveguide-Based Sensors
The optical waveguide (WG) is one of the fundamental components of integrated photonics. Polymer WGs can operate in either single-mode (with core diameters between 2 μm and 5 μm) or multimode (with core dimensions generally between 30 μm and 500 μm) regimes. They are both entirely consistent with the matching optical fiber type due to the similar mode field diameter. A WG is simply utilized as a light link to connect external instruments to a sampling point or an optical sensing element in an extrinsic sensor. In biomedicine, environmental monitoring, process control, and safety, extrinsic sensors are already widely employed.
  • 1.9K
  • 08 Mar 2023
Topic Review
Population-Based Deep Reinforcement Learning
Many real-world applications can be described as large-scale games of imperfect information, which require extensive prior domain knowledge, especially in competitive or human–AI cooperation settings. Population-based training methods have become a popular solution to learn robust policies without any prior knowledge, which can generalize to policies of other players or humans. 
  • 1.9K
  • 15 Jun 2023
Topic Review
Privacy-Preserving Blockchain Technologies
The main characteristics of blockchains, such as security and traceability, have enabled their use in many distinct scenarios, such as the rise of new cryptocurrencies and decentralized applications (dApps). However, part of the information exchanged in the typical blockchain is public, which can lead to privacy issues. To avoid or mitigate these issues, some blockchains are applying mechanisms to deal with data privacy. Trusted execution environments, the basis of confidential computing, and secure multi-party computation are two technologies that can be applied in that sense. 
  • 1.9K
  • 24 Aug 2023
Topic Review
SARS-CoV-2 Main Protease
The main protease (Mpro) of the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was subjected to hyphenated pharmacophoric-based and structural-based virtual screenings using a library of microbial natural products (>24,000 compounds). Subsequent filtering of the resulted hits according to Lipinski’s rules was applied to select only the drug-like molecules. Top-scoring hits were further filtered out depending on their ability to show constant good binding affinities towards the molecular dynamic simulation (MDS)-derived enzyme’s conformers. Final MDS experiments were performed on the ligand-protein complexes to verify their binding modes and calculate their binding free energy. Consequently, a final selection of six compounds of microbial origin was proposed to possess high potential as anti-SARS-CoV-2 drug candidates. Our study provides insight into the role of the Mpro structural flexibility during interactions with the possible inhibitors and sheds light on the structure-based design of anti-coronavirus disease 2019 (COVID-19) therapeutics targeting SARS-CoV-2
  • 1.9K
  • 26 Oct 2020
Topic Review
Promising Lead Compounds for Resistant-Tuberculosis
According to WHO report, globally about 10 million active tuberculosis cases, resulting in about 1.6 million deaths, further aggravated by drug-resistant tuberculosis and/or comorbidities. Incomplete therapeutic regimen, meager dosing, and the capability of the latent and/or active state tubercular bacilli to abide and do survive against contemporary first-line and second-line antitubercular drugs escalate the prevalence of drug-resistant tuberculosis. To explore and identify the most potential antitubercular drug candidate among various reported compounds, here we focused to highlight the promising lead derivatives of isoniazid, coumarin, griselimycin, and antimicrobial peptides. The aim of the present review is to fascinate significant lead compounds in the development of potential clinical drug candidates that might be more precise and effective against drug-resistant tuberculosis, the world research looking for a long time.
  • 1.9K
  • 10 Dec 2020
Topic Review
Age-Related Macular Degeneration (AMD)
Age-related macular degeneration (AMD) is a common irreversible sight-threatening disease characterized by progressive degeneration of the central retina, preferentially involving the retinal photoreceptors, the retinal pigment epithelium (RPE), the Bruch’s membrane (BM), or the choroidal microcirculation in the macular region.
  • 1.9K
  • 22 Sep 2021
Topic Review
Advances of Microneedles in Biomedical Applications
A microneedle (MN) is a painless and minimally invasive drug delivery device initially developed in 1976. As microneedle technology evolves, microneedles with different shapes (cone and pyramid) and forms (solid, drug-coated, hollow, dissolvable and hydrogel-based microneedles) have been developed. 
  • 1.9K
  • 18 Oct 2021
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