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Topic Review Peer Reviewed
Enantiomers and Their Resolution
Enantiomers share the same chemical formula but have different chemical structures, i.e., type of isomers. Enantiomers are present in several drugs, perfumes, food, and are a fundamental part of biomolecules. This subject is highly important for pharmaceutical companies. Enantiomeric drugs present different actuation in the human body; depending on the compound, one might combat the symptom, whereas its pair might cause damage. The separation of pairs of enantiomers requires a chiral environment that provokes a structural imbalance that conventional methods cannot provide. Enantioresolution is one of the most promissory studies that benefit several areas, such as pharmaceutical, biotechnology, food industry, and fine chemistry. Its resolution is of great importance, therefore, its main mechanisms of resolution will be explained herein.
  • 2.4K
  • 14 Apr 2022
Topic Review
Drilling Fluid Loss and Lost Circulation Control Technology
Lost circulation in fractured formation is the first major technical problem that restricts improvements in the quality and efficiency of oil and gas drilling engineering. Improving the success rate of one-time lost circulation control is an urgent demand to ensure “safe, efficient and economic” drilling in oilfields all over the world. 
  • 2.4K
  • 13 May 2022
Topic Review
Cerebrospinal Fluid Leak
A cerebrospinal fluid leak (CSF leak or CSFL) is a medical condition where the cerebrospinal fluid (CSF) surrounding the brain or spinal cord leaks out of one or more holes or tears in the dura mater. A cerebrospinal fluid leak can be either cranial or spinal, and these are two different disorders. A spinal CSF leak can be caused by one or more meningeal diverticula or CSF-venous fistulas not associated with an epidural leak. A CSF leak is either caused by trauma including that arising from medical interventions or spontaneously sometimes in those with predisposing conditions (known as a spontaneous cerebrospinal fluid leak or sCSF leak). Traumatic causes include a lumbar puncture noted by a post-dural-puncture headache, or a fall or other accident. Spontaneous CSF leaks are associated with heritable connective tissue disorders including Marfan syndrome and Ehlers–Danlos syndromes. A loss of CSF greater than its rate of production leads to a decreased volume inside the skull known as intracranial hypotension. Any CSF leak is most often characterized by orthostatic headaches, which worsen when standing, and improve when lying down. Other symptoms can include neck pain or stiffness, nausea, vomiting, dizziness, fatigue, and a metallic taste in the mouth. A CT myelography scan can identify the site of a cerebrospinal fluid leakage. Once identified, the leak can often be repaired by an epidural blood patch, an injection of the patient's own blood at the site of the leak, a fibrin glue injection, or surgery. The set of symptoms associated with a sCSF leak is referred to as a spontaneous cerebrospinal fluid leak syndrome (SCSFLS). A sCSF leak is uncommon but not rare, affecting at least one in 20,000 people and many more who go undiagnosed every year. On average, the condition develops at age 42, and women are twice as likely to be affected. Some people with a sCSF leak have a chronic leak of cerebrospinal fluid despite repeated patching attempts, leading to long-term disability due to pain and being unable to be upright, and surgery is often needed. SCSFLS was first described by German neurologist Georg Schaltenbrand in 1938 and by American neurologist Henry Woltman of the Mayo Clinic in the 1950s.
  • 2.4K
  • 11 Oct 2022
Topic Review
Sustainable Triple-Layered Business Model Canvas
Developing more sustainable business models (BMs) has become increasingly crucial for the survival of agri-food industries as environmental and social pressures are escalating, and the fruit and vegetable (F&V) industry is no exception to this pattern.
  • 2.4K
  • 19 Oct 2023
Topic Review
COVID-19 Diagnosis
The world is grappling with the coronavirus disease 2019 (COVID-19) pandemic, the causative agent of which is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 symptoms are similar to the common cold, including fever, sore throat, cough, muscle and chest pain, brain fog, dyspnoea, anosmia, ageusia, and headache.
  • 2.4K
  • 27 Jun 2022
Topic Review
Compound Parabolic Concentrator-Based Hybrid Solar Photovoltaic/Thermal Collectors
The compound parabolic concentrating (CPC) collectors belong to a class of concentrators called non-imaging concentrators. These concentrators allow the design of optical systems that can attain maximum geometric concentrations permitted by laws of physical conservation for a given angular field. As opposed to imaging or focusing concentrators, the concentrators based on non-imaging optics are capable of achieving moderate levels of concentration without tracking the sun.
  • 2.4K
  • 23 May 2022
Topic Review
Monetary Policy Committee
The Monetary Policy Committee (MPC) is a committee of the Bank of England, which meets for three and a half days, eight times a year, to decide the official interest rate in the United Kingdom (the Bank of England Base Rate). It is also responsible for directing other aspects of the government's monetary policy framework, such as quantitative easing and forward guidance. The Committee comprises nine members, including the Governor (from 2013 Mark Carney), and is responsible primarily for keeping the Consumer Price Index (CPI) measure of inflation close to a target set by the government (2% per year as of 2016). Its secondary aim – to support growth and employment – was reinforced in March 2013. Announced on 6 May 1997, only five days after that year's General Election, and officially given operational responsibility for setting interest rates in the Bank of England Act 1998, the Committee was designed to be independent of political interference and thus to add credibility to interest rate decisions. Each member has one vote, for which they are held to account: full minutes of each meeting are published alongside the Committee's monetary policy decisions, and members are regularly called before the Treasury Select Committee, as well as speaking to wider audiences at events during the year.
  • 2.4K
  • 19 Oct 2022
Topic Review
The Foundations of Arithmetic
The Foundations of Arithmetic (German: Die Grundlagen der Arithmetik) is a book by Gottlob Frege, published in 1884, which investigates the philosophical foundations of arithmetic. Frege refutes other theories of number and develops his own theory of numbers. The Grundlagen also helped to motivate Frege's later works in logicism. The book was not well received and was not read widely when it was published. It did, however, draw the attentions of Bertrand Russell and Ludwig Wittgenstein, who were both heavily influenced by Frege's philosophy. An English translation was published (Oxford, 1950) by J. L. Austin, with a second edition in 1960.
  • 2.4K
  • 05 Dec 2022
Topic Review
Image-Based Obstacle Detection Methods
Mobile robots lack a driver or a pilot and, thus, should be able to detect obstacles autonomously. These various image-based obstacle detection techniques include Unmanned Surface Vehicles (USVs), Unmanned Aerial Vehicles (UAVs), and Micro Aerial Vehicles (MAVs). The techniques were divided into monocular and stereo. The former uses a single camera, while the latter makes use of images taken by two synchronised cameras. Monocular obstacle detection methods are discussed in appearance-based, motion-based, depth-based, and expansion-based categories. Monocular obstacle detection approaches have simple, fast, and straightforward computations. Thus, they are more suited for robots like MAVs and compact UAVs, which usually are small and have limited processing power. On the other hand, stereo-based methods use pair(s) of synchronised cameras to generate a real-time 3D map from the surrounding objects to locate the obstacles. Stereo-based approaches have been classified into Inverse Perspective Mapping (IPM)-based and disparity histogram-based methods. Whether aerial or terrestrial, disparity histogram-based methods suffer from common problems: computational complexity, sensitivity to illumination changes, and the need for accurate camera calibration, especially when implemented on small robots.
  • 2.4K
  • 24 Oct 2022
Topic Review
Empathy Gap
A hot-cold empathy gap is a cognitive bias in which people underestimate the influences of visceral drives on their own attitudes, preferences, and behaviors. The most important aspect of this idea is that human understanding is "state-dependent". For example, when one is angry, it is difficult to understand what it is like for one to be calm, and vice versa; when one is blindly in love with someone, it is difficult to understand what it is like for one not to be, (or to imagine the possibility of not being blindly in love in the future). Importantly, an inability to minimize one's gap in empathy can lead to negative outcomes in medical settings (e.g., when a doctor needs to accurately diagnose the physical pain of a patient), and in workplace settings (e.g., when an employer needs to assess the need for an employee's bereavement leave). Hot-cold empathy gaps can be analyzed according to their direction: They can also be classified in regards to their relation with time (past or future) and whether they occur intra- or inter-personally: The term hot-cold empathy gap was coined by Carnegie Mellon University psychologist George Loewenstein. Hot-cold empathy gaps are one of Loewenstein's major contributions to behavioral economics.
  • 2.4K
  • 04 Nov 2022
Biography
Josh Tillman
Joshua Michael Tillman[1] (born May 3, 1981), also known as Father John Misty and previously J. Tillman, is an American singer-songwriter, musician, and record producer.[2] Maintaining a steady output of solo recordings since 2004,[3] Tillman had been a member of or toured with Demon Hunter, Saxon Shore, Fleet Foxes, Jeffertitti's Nile,[4] Pearly Gate Music,[5] Siberian,[6] Har Mar Superstar,[7
  • 2.4K
  • 15 Nov 2022
Topic Review
Electro-Osmosis
Electroosmotic flow (or electro-osmotic flow, often abbreviated EOF; synonymous with electroosmosis or electroendosmosis) is the motion of liquid induced by an applied potential across a porous material, capillary tube, membrane, microchannel, or any other fluid conduit. Because electroosmotic velocities are independent of conduit size, as long as the electrical double layer is much smaller than the characteristic length scale of the channel, electroosmotic flow will have little effect. Electroosmotic flow is most significant when in small channels. Electroosmotic flow is an essential component in chemical separation techniques, notably capillary electrophoresis. Electroosmotic flow can occur in natural unfiltered water, as well as buffered solutions.
  • 2.4K
  • 29 Nov 2022
Topic Review Peer Reviewed
Pandemic Economic Crises
The market serves as the convergence point of supply and demand and represents the process through which market relations between economic units materialize. From a global perspective, the focus shifts to the world market, which is the fundamental structure on which the global economy is based. The world economy operates as a very complex ecosystem. When it is exposed to the extremely damaging effects of a global pandemic, the term of a pandemic economic crisis becomes relevant.
  • 2.4K
  • 04 Dec 2023
Topic Review
Trends in Bioenergy Production
A wide range of studies have been performed in the field of the usage of biomass for energy production, in order to contribute to the green transition from fossil fuels to renewable energies. Over the past 20 years (from 2000 to 2019), approximately 10,000 articles have been published in the “Agricultural and Biological Sciences” field on this theme, covering all stages of production—from the harvesting of crops to the particular type of energy produced. Articles were obtained from the SCOPUS database and examined with a text mining tool in order to analyze publication trends over the last two decades. Publications per year in the bioenergy theme have grown from 91 in 2000 to 773 in 2019. In particular the analyses showed how environmental aspects have increased their importance (from 7.3% to 11.8%), along with studies related to crop conditions (from 10.4% to 18.6%). Regarding the use of energy produced, growing trends were recognized for the impact of biofuels (mentions moved from 0.14 times per article in 2000 to 0.38 in 2019) and biogases (from 0.14 to 0.42 mentions).
  • 2.4K
  • 28 Aug 2020
Topic Review
Stimuli-Responsive Drug Delivery Systems
Recent advancements in the arena of onco-targeted therapies have enabled safe and effective tumor-specific localization through stimuli-responsive drug delivery systems. Owing to their promising characteristic features, stimuli-responsive drug delivery platforms have revolutionized the chemotherapy-based treatments with added benefits of enhanced bioavailability and selective cytotoxicity of cancer cells compared to the conventional modalities. The insensitivity of stimuli-responsive drug delivery platforms when exposed to normal cells prevents the release of cytotoxic drugs into the normal cells and therefore alleviates the off-target events associated with chemotherapy. Contrastingly, they showed amplified sensitivity and triggered release of chemotherapeutic payload when internalized into the tumor microenvironment causing maximum cytotoxic responses and the induction of cancer cell necrosis.
  • 2.4K
  • 10 Mar 2021
Topic Review
Marine Nepheloid Layer
Marine nepheloid layer is a turbid layer containing significantly more suspended particles than the adjacent layers in oceans. The suspended particles may collide and form large falling particle aggregates known as marine snow. Although the nepheloid layer continually changes with time and space, it shows certain temporal and spatial stability. A marine nepheloid layer could last a few days to years, with a thickness ranging from meters to kilometers.
  • 2.4K
  • 16 Mar 2022
Topic Review
Battery Safety
Battery safety is a prominent concern for the deployment of electric vehicles (EVs). The battery powering an EV contains highly energetic active materials and flammable organic electrolytes. Usually, an EV battery catches fire due to its thermal runaway, either immediately at the time of the accident or can take a while to gain enough heat to ignite the battery chemicals. There are numerous battery abuse testing standards and regulations available globally. Therefore, battery manufacturers are always in dilemma to choose the safest one. Henceforth, to find the optimal outcome of these two major issues, six standards (SAE J2464:2009, GB/T 31485-2015:2015, FreedomCAR:2006, ISO 12405-3:2014, IEC 62660-2:2010, and SAND2017-6295:2017) and two regulations (UN/ECE-R100.02:2013 and GTR 20:2018), that are followed by more than fifty countries in the world, are investigated in terms of their abuse battery testing conditions (crush test).
  • 2.4K
  • 11 Nov 2021
Topic Review
Canine Seventh Lumbar Vertebra Fracture
Lumbosacral traumatic injuries are reported as 39% of canine vertebral lesions. This area is prone to fracture and luxation. Non-ambulatory paraparesis/plegia, sciatic nerve involvement, faecal/urinary incontinence, and severe back lumbar pain were the most reported signs. Survey radiographs were the most reported technique to confirm the diagnoses. The seventh lumbar vertebra fracture, despite the different surgical techniques performed, had a favourable prognosis for long-term outcome and neurological recovery. 
  • 2.4K
  • 23 Feb 2022
Topic Review
Hybrid Rye Breeding and Production
Hybrid rye breeding leads to considerably higher grain yield and a higher revenue to the farmer. The basis of hybrid seed production is the CMS-inducing Pampa (P) cytoplasm derived from an Argentinean landrace and restorer-to-fertility (Rf) genes. Breeding is based on inbred line development and intensive testing for line per se performance and general combining ability (GCA). The finally selected inbred lines are used to compose a topcross hybrid with two genetically different seed parent lines (A-P, B-N) and a restorer synthetic composed of two S2 lines (SynRf). European restorer sources show low-to-moderate pollen-fertility levels. This results in higher susceptibility to ergot (Claviceps purpurea) because rye pollen and ergot spores are in strong competition for the unfertilized stigma. Rf genes from non-adapted Iranian primitive rye and old Argentinean cultivars proved to be most effective. The major Rf gene in these sources was localized on chromosome 4RL, which is also a hotspot of restoration in other Triticeae. Commercial hybrids with these Rf genes showed a similar low ergot infection when compared with population cultivars. The great future challenges of climate change, such as increased drought stress tolerance, improved lodging tolerance, as well as the increasing need for resistant varieties can effectively only be met by hybrid breeding.
  • 2.4K
  • 06 May 2022
Topic Review
General Theory of Photodetectors
Photodetectors are one of the popular types of technology used in ultraviolet radiation research. They are widely used in the industrial area (flame detectors, fire alarm systems, extreme UV lithography), national security (missile defense, military recognition, explosives detection, forensic analysis, secure communications), in fields such as medicine (UV imaging, protein analysis, and DNA sequencing) or biology (biological agent detection), and when dealing with environmental issues (ozone detection, air pollution determination, disinfection, and decontamination).
  • 2.4K
  • 19 May 2023
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