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Topic Review
Petya (Malware)
Petya is a family of encrypting malware that was first discovered in 2016. The malware targets Microsoft Windows–based systems, infecting the master boot record to execute a payload that encrypts a hard drive's file system table and prevents Windows from booting. It subsequently demands that the user make a payment in Bitcoin in order to regain access to the system. The Petya malware had infected millions of people during its first year of its release. The maker of the Petya malware was arrested and fined.[citation needed] Variants of Petya were first seen in March 2016, which propagated via infected e-mail attachments. In June 2017, a new variant of Petya was used for a global cyberattack, primarily targeting Ukraine . The new variant propagates via the EternalBlue exploit, which is generally believed to have been developed by the United States . National Security Agency (NSA), and was used earlier in the year by the WannaCry ransomware. Kaspersky Lab referred to this new version as NotPetya to distinguish it from the 2016 variants, due to these differences in operation. In addition, although it purports to be ransomware, this variant was modified so that it is unable to actually revert its own changes. The NotPetya attacks have been blamed on the Russian government, specifically the Sandworm hacking group within the GRU Russian military intelligence organization, by security researchers, Google, and several governments.
  • 1.4K
  • 17 Nov 2022
Topic Review
Evolution of Access Network Sharing
Network sharing is part of a fundamental principle of statistical multiplexing of link capacity. Regardless of whether the nodes are setting up connections that reserve capacity in the Plain Old Telephone Service (POTS), or sending packets in a connection-less packet-switched network, the overall link capacity is only a fraction of the total interconnection capacity required if all nodes attempted communicating at once. Network sharing also applies to the progressive aggregation of link capacity where the ratio of multiplexing increases in moving from the access towards the core. From the mid-90s’, the concept of sharing was extended to also cover the multi-tenant use of the network, where third party network operators compete with the incumbent national operator, so that the same common infrastructure is shared across multiple competing entities. The degree to which infrastructure is shared is limited, on the one hand by physical and logical boundaries that separate resources, and on the other hand by economic complexities such as settlements, agreements and regulations that complicate the sharing process.
  • 1.4K
  • 27 Oct 2020
Topic Review
Golden Perch
Freshwater ecosystems and their associated biota have been negatively impacted by the human development of water resources. Fundamental to restoration activities for target species is an understanding of the factors affecting population decline or recovery. Within Australia’s Murray–Darling Basin, recovery efforts to address the population decline of native freshwater fish include stock enhancement, habitat restoration, and the delivery of environmental water. Essential to guiding future management actions is information to assess the efficacy of these efforts. We undertook a study to investigate whether natural spawning and recruitment, stock enhancement, or a combination of the two is contributing to sustaining populations of golden perch (Macquaria ambigua) in the highly regulated Lachlan River, Australia. Otolith microchemistry and genetic analyses were used as complementary tools to determine the source (hatchery origin or wild-spawned) of existing populations in the catchment. We identified that natural spawning and recruitment was contributing to riverine populations in some years but that populations were heavily reliant on stocking. It was not possible to distinguish hatchery and wild-born fish using genetic tools, highlighting the value of using multiple lines of evidence to establish causal mechanisms contributing to population recovery.
  • 1.4K
  • 27 Oct 2020
Topic Review
Environmental Remediation of Antineoplastic Drugs
The global burden of cancer is on the rise, and as a result, the number of therapeuticsadministered for chemotherapy is increasing. The occupational exposure, recalcitrant nature andecotoxicological toxicity of these therapeutics, referred to as antineoplastic (ANP) drugs, have raisedconcerns about their safe remediation. This review provides an overview of the environmental sourceof ANPs agents, with emphasis on the currently used remediation approaches. Outpatient excreta,hospital euents, and waste from pharmaceutical industries are the primary source of ANP waste.The current review describes various biotic and abiotic methods used in the remediation of ANPdrugs in the environment. Abiotic methods often generate transformation products (TPs) of unknowntoxicity. In this light, obtaining data on the environmental toxicity of ANPs and its TPs is crucial todetermine their toxic e ect on the ecosystem. We also discuss the biodegradation of ANP drugs usingmonoculture of fungal and bacterial species, and microbial consortia in sewage treatment plants.The current review e ort further explores a safe and sustainable approach for ANP waste treatmentto replace existing chemical and oxidation intensive treatment approaches. To conclude, we assessthe possibility of integrating biotic and abiotic methods of ANP drug degradation.
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  • 26 Aug 2020
Topic Review
Potential Photodynamic Diagnosis Targets
Photodynamic diagnosis and therapy (PDD and PDT) are emerging, non/minimally invasive techniques for cancer diagnosis and treatment. Both techniques require a photosensitizer and light to visualize or destroy cancer cells. However, a limitation of conventional, non-targeted PDT is poor selectivity, causing side effects. The bioconjugation of a photosensitizer to a tumor-targeting molecule, such as an antibody or a ligand peptide, is a way to improve selectivity. The bioconjugation strategy can generate a tumor-targeting photosensitizer conjugate specific for cancer cells, or ideally, for multiple tumor compartments to improve selectivity and efficacy, such as cancer stem cells and tumor neovasculature within the tumor microenvironment. If successful, such targeted photosensitizer conjugates can also be used for specific visualization and detection of cancer cells and/or tumor angiogenesis (an early event in tumorigenesis) with the hope of an early diagnosis of cancer.
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  • 03 Dec 2020
Topic Review
Precision Medicine
Precision medicine is "an emerging approach for disease treatment and prevention that takes into account individual variability in genes, environment, and lifestyle for each person."
  • 1.4K
  • 08 Apr 2021
Topic Review
Vitamin C: AA vs. DHA
The reduced form of vitamin C (ascorbic acid, AA) is an essential micronutrient of small size; it is soluble in water and has two dissociable protons with pKa values of 4.2 and 11.8. At physiological pH, its reduced form predominates as the monovalent ascorbate anion (AA); when it loses the second proton, it is oxidized to dehydroascorbic acid (DHA). Most mammals can synthesize vitamin C from D-glucose in the liver, except guinea pigs, bats, and higher primates, including humans, due to the absence of the enzyme L-gulonolactone oxidase, which catalyzes the last step of the bio-synthesis of vitamin C . Therefore, to meet the body’s requirements, vitamin C must be incorporated into the diet. The best-known function of vitamin C is as an anti-oxidant agent that can act as a cofactor of enzymatic reactions involved in the synthe sis of catecholamines, carnitine, cholesterol, amino acids, and some hormonal peptides, as well as in the maintenance of brain function and the protection of central nervous system (CNS) structures . AA uptake in different cells is performed by the sodium-ascorbate cotransporters SVCT1 and SVCT2, which stereospecifically transport the reduced form of vitamin C, L-ascorbate . Vitamin C can also be transported in its oxidized form, DHA, through the facilitative glucose transporters GLUT1, GLUT2, GLUT3, GLUT4, and GLUT8. However, for a long time, it has been postulated that the contribution of DHA to the accumulation of vitamin C in tissues is relatively low. 
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  • 20 Feb 2021
Topic Review
Comorbidities in Rheumatoid Arthritis
Comorbidities in patients with rheumatoid arthritis (RA) are often associated with poor health outcomes and increased mortality. Treatment decisions should consider these comorbidities due to known or suspected associations with certain drug classes. In clinical practice, it is critical to balance potential treatment benefit against the possible risks for comorbidities as well as the articular manifestations of RA. This entry summarises the current literature relating to prevalence and risk factors for the important comorbidities of cardiovascular disease, infections, lymphomas and nonmelanoma skin cancers in patients with RA. The impact on patient outcomes and the interplay between these comorbidities and the therapeutic options currently available, including tumour necrosis factor inhibitors and newer biological therapies, are also explored. As newer RA therapies are developed, and patients gain wider and earlier access to advanced therapies, in part due to the emergence of biosimilars, it is important to consider the prevention or treatment of comorbidities as part of the overall management of RA.
  • 1.4K
  • 17 Dec 2024
Topic Review
Plant Mitochondria: Fusion and Fission
Plant mitochondria have large genomes to house a small number of key genes. Most mitochondria do not contain a whole genome. To maintain the mitochondrial genes, so important for energy production, the fusion and fission of mitochondria is critical. The dynamin related proteins DRP 3A and 3B drive the fission process. Fusion is less well understood but the MIRO2 gene appears to have a significant role. Massive mitochondrial fusion and subsequent fission prior to flowering, in the enlarging zygote and at germination aids genome repair, conservation of critical genes and may give an energy boost to key stages of the life cycle.
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  • 31 May 2021
Topic Review
Integrated Maritime Policy
Integrated and ecosystem-based maritime policy should be seen as a versatile multidisciplinary and cross-sectoral instrument for international dialogue within the region.
  • 1.4K
  • 17 Jun 2021
Topic Review
CD147
Microenvironment plays a crucial role in tumor development and progression. Cancer cells modulate the tumor microenvironment, which also contribute to resistance to therapy. Identifying biomarkers involved in tumorigenesis and cancer progression represents a great challenge for cancer diagnosis and therapeutic strategy development. CD147 is a glycoprotein involved in the regulation of the tumor microenvironment and cancer progression by several mechanisms—in particular, by the control of glycolysis and also by its well-known ability to induce proteinases leading to matrix degradation, tumor cell invasion, metastasis and angiogenesis. 
  • 1.4K
  • 12 Aug 2021
Topic Review
Improving Water Efficiency in a Swimming-Pool Complex
Concomitantly, the possibility of recycling and reusing the water from filter backwashing was evaluated. The pools consumed 25.6% of water, the filter backwashing 24.5%, and the showers 34.7%. Despite the current impossibility of reducing water consumption in pools and filter backwashing, it is feasible to promote more efficient use of water through reducing water consumption by adopting simple water-saving initiatives for showers, taps, and flushing cisterns. These were organized into three distinct scenarios: (a) flushing cistern volume adjustment and the replacement of washbasin and kitchen taps; (b) flushing cistern volume adjustment and shower replacement and (c) flushing cistern volume adjustment, shower, washbasin, and kitchen taps replacement. Under scenarios 1, 2, and 3, the water consumption reduction was 8.0, 13.2, and 20.4%, respectively. The initial investment for scenario 1 was €2290.5, €859.0 for scenario 2 and €3149.5 for scenario 3; the annual water bill reduction was €7115.4, €11,518.1, and €17,655.9, respectively. Therefore, the turnover of the investment was four (scenario 1), one (scenario 2), and three months (scenario 3). The filter washings attained the required standard for irrigation after being subjected to 15 h of sedimentation. 
  • 1.4K
  • 14 Nov 2021
Topic Review
Vector Beam with Longitudinally Varying Polarization during Propagation
The vector optical beam with longitudinally varying polarization during propagation in free space has attracted significant attention in recent years. Compared with traditional vector optical beams with inhomogeneous distribution of polarization in the transverse plane, manipulating the longitudinal distribution of polarization provides a new dimension for the expansion of the applications of vector optical beams in volume laser machining, longitudinal detection, and in vivo micromanipulation. 
  • 1.4K
  • 29 Nov 2021
Topic Review
A Complex Disease: Non-Small Cell Lung Cancer
Non-small cell lung cancer (NSCLC) is a complex disease often driven by activating mutations or amplification of the epidermal growth factor receptor (EGFR) gene, which expresses a transmembrane receptor tyrosine kinase. Targeted anti-EGFR treatments include small-molecule tyrosine kinase inhibitors (TKIs), among which gefitinib and erlotinib are the best studied, and their function more often imaged. TKIs block EGFR activation, inducing apoptosis in cancer cells addicted to EGFR signals. 
  • 1.4K
  • 28 Feb 2022
Topic Review
FreeTrack
FreeTrack is a general-purpose optical motion tracking application for Microsoft Windows, released under the GNU General Public License, that can be used with common inexpensive cameras. Its primary focus is head tracking with uses in virtual reality, simulation, video games, 3D modeling, computer aided design and general hands-free computing to improve computer accessibility. Tracking can be made sensitive enough that only small head movements are required so that the user's eyes never leave the screen. A camera is positioned to observe a rigid point model worn by the user, the points of which need to be isolated from background light by means of physical and software filtering. Motion is tracked with up to six degrees of freedom (6DOF): yaw, pitch, roll, left/right, up/down and forward/back. Windows-compatible video devices like webcams are supported, as well as special Nintendo Wii Remote camera, iPhone Truedepth camera with Eyeware Beam, and NaturalPoint cameras (TrackIR, SmartNav and OptiTrack). FreeTrack can output head-tracking data to programs directly using its own open interface, as well as TrackIR, SimConnect and FSUIPC interfaces. Programs that support these interfaces are regarded as being FreeTrack-compatible. FreeTrack can also emulate mouse, keyboard, and joystick (via PPJoy) if a program does not support a direct interface. FreeTrack is coded in Delphi 7 and uses DirectShow and DirectX. Head tracking is achieved using implementations of DeMenthon's four-point iterative pose estimation algorithm (POSIT) and Alter's three point geometric algorithm.
  • 1.4K
  • 24 Oct 2022
Topic Review
Dapagliflozin as a Drug in Heart Failure
Dapagliflozin is a selective SGLT-2 inhibitor that reduces renal glucose absorption by inhibiting the SGLT-2 receptors present in the S1 region of the proximal kidney tubules.
  • 1.4K
  • 22 Nov 2022
Topic Review
ER Stress and the Unfolded Protein Response
The endoplasmic reticulum (ER), a eukaryotic organelle, is the major site of protein biosynthesis. The disturbance of ER function by biotic or abiotic stress triggers the accumulation of misfolded or unfolded proteins in the ER. The unfolded protein response (UPR) is the best-studied ER stress response. This transcriptional regulatory system senses ER stress, activates downstream genes that function to mitigate stress, and restores homeostasis. In addition to its conventional role in stress responses, reports indicate that the UPR is involved in plant growth and development.
  • 1.4K
  • 09 Dec 2022
Topic Review
Aberrant Circadian Rhythm in Huntington’s Disease
Huntington’s disease (HD) is a progressive neurodegenerative disorder characterized by abnormal progressive involuntary movements, cognitive deficits, sleep disturbances, and psychiatric symptoms. Notably, gamma-aminobutyric acid (GABA)-ergic neurons that express the vasoactive intestinal peptide (VIP) in the brain play a key role in the regulation of circadian rhythm and neuroplasticity. While an abnormal clock gene pathway has been associated with the inactivation of GABAergic VIP neurons, recent studies suggest the activation of this neuronal population in the brain positively contributes to neuroplasticity.
  • 1.4K
  • 22 Dec 2022
Topic Review
Oxidative Stress and Minimal and Mild Endometriosis-Related Infertility
Oxidative stress (OS) plays an important role in a variety of physiological and pathological processes of the female reproductive system.The relationship between OS and endometriosis has been of particular interest, and a theory has been suggested that OS may be a cause of endometriosis development. 
  • 1.4K
  • 06 Mar 2023
Topic Review
Genetics of Alternative Lateral Horse Gaits
In addition to the “natural” gaits of walk, trot, and canter/gallop found in nearly all horse breeds, there are additional gaits spontaneously displayed in certain domestic horse breeds (i.e., gaited horses). All of these additional gaits are symmetrical lateral sequence gaits, i.e., possessing a footfall pattern of left hind, left front, right hind, and right front, and so can be called alternative lateral gaits. What is known about the genetics of alternative lateral gaits is explored. Studies have shown a strong correlation of gaitedness in horses with possession of the A-allele of the DMRT3 "gait keeper" gene. Horses homozygous for the A-allele are able to perform a pacing gait and sustain it at high speeds. Horses that can perform a running walk, rack, or broken pace (stepping pace) are either heterozygous or homozygous for the A-allele of the "gait keeper" gene. The A-allele of this gene functions by disrupting coordination of diagonal or contralateral limbs and allowing retention of square or "singlefoot" gaits, wherein limbs move mostly independently of each other, into intermediate speed ranges. It now seems, however, that the broken trot gait (i.e. the fox trot) is not governed by the DMRT3 gene as select horse breeds lacking the A-allele can still perform this gait.
  • 1.4K
  • 17 Aug 2023
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