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Topic Review
Furstenberg–Sárközy Theorem
The Furstenberg–Sárközy theorem is a result in additive number theory on sets of numbers no two of which differ by a square. It states that, if [math]\displaystyle{ S }[/math] is a set of natural numbers with the property that no two numbers in [math]\displaystyle{ S }[/math] differ by a square number, then the natural density of [math]\displaystyle{ S }[/math] is zero. That is, for every [math]\displaystyle{ \varepsilon \gt 0 }[/math], and for all sufficiently large [math]\displaystyle{ n }[/math], the fraction of the numbers up to [math]\displaystyle{ n }[/math] that are in [math]\displaystyle{ S }[/math] is less than [math]\displaystyle{ \varepsilon }[/math]. Equivalently, every set of natural numbers with positive upper density contains two numbers whose difference is a square (and more strongly infinitely many such pairs). The theorem is named after Hillel Furstenberg and András Sárközy, who proved it in the late 1970s.
  • 1.5K
  • 10 Nov 2022
Topic Review
Endometrial Hyperplasia
Endometrial hyperplasia without cytological atypia is commonly treated with progestins, but other treatments may be available with equivalent efficacy and reduced side effects. Here, we evaluate the effect of genistein aglycone on angiogenesis and apoptosis-related markers women with endometrial hyperplasia. Premenopausals (n=38) with nonatypical endometrial hyperplasia were administered either genistein aglycone (54 mg/day, n=19) or norethisterone acetate (10 mg/day, n=19) on days 16–25 of the menstrual cycle and evaluated for 6 months. Biopsies were taken during hysteroscopy at baseline and 6 months, and symptoms including excessive uterine bleeding were assessed at baseline and 3 and 6 months following recruitment. The expression of angiogenesis (Vegf), epithelial (Egf and Tgfb), and apoptosis-related (Bax, Bcl-2, and Casp-9) molecules, were assessed in uterine biopsies at baseline and after 6 months of therapy. Follicle-stimulating hormone, luteinizing hormone, estradiol, SHBG, and progesterone levels were also measured. After 6 months, 42% of genistein aglycone-administered patients had a significant improvement of symptoms compared to 47% of norethisterone acetate subjects. No significant differences were noted in hormone levels for any treatment. Gene expression revealed a significant reduction in Vegf, Egf, and Tgfb (P<0.05 versus baseline), and an increase in proapoptotic molecules (Bax and Casp-9), with a concomitant decrease in Bcl-2 values (P<0.05) in both groups. These results suggest that genistein aglycone might be useful for the management of endometrial hyperplasia without atypia in women who cannot or do not wish to be treated with progestin.
  • 1.5K
  • 01 Nov 2020
Topic Review
Tea Tree Oil Induced Resistance
The essential tea tree oil (TTO) derived from Melaleuca alternifolia plant is widely used as a biopesticide to protect crops from several plant-pathogens. TTO was approved by the European Union (EU) and included in the positive list of the EU, in Annex I of Directive 91/414/EEC for registration of Plant Protection Products. TTO is classified as a low risk substance in Europe. This oil is in large use in cosmetics and in medicine.
  • 1.5K
  • 23 Oct 2020
Topic Review
Molecules of the Week
"Molecules of the Week" is a new project to collect and show the discovery of novel molecules, compounds as well as the researchers' story behind it.
  • 1.5K
  • 05 Nov 2021
Topic Review
ADLD
Autosomal dominant leukodystrophy with autonomic disease (ADLD) is one of a group of genetic disorders called leukodystrophies. Leukodystrophies are characterized by abnormalities of the nervous system's white matter, which consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates and protects nerve fibers and promotes the rapid transmission of nerve impulses.
  • 1.5K
  • 04 Jan 2021
Topic Review
Signal-Amplification Strategies for PAD
Paper-based analytical devices (PADs) have emerged as a promising approach to point-of-care (POC) detection applications in biomedical and clinical diagnosis owing to their advantages, including cost-effectiveness, ease of use, and rapid responses as well as for being equipment-free, disposable, and user-friendly. Total signal-amplification strategies in PADs involving colorimetry, luminescence, surface-enhanced Raman scattering, photoacoustic, photothermal, and photoelectrochemical methods as well as nucleic acid-mediated PAD modifications. 
  • 1.5K
  • 25 May 2021
Topic Review
Structure of Rubisco，Dinoflagellates
Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), is one of the best studied enzymes. Rubisco catalyses CO2 assimilation and therefore tt is crucial for photosynthesis, and for all of biosphere’s productivity. There are four isoforms of this enzyme, differing by amino acid sequence composition and quaternary structure. However, there is still a group of organisms, dinoflagellates, single-cell eukaryotes, that are confirmed to possess Rubisco, but no successful purification of the enzyme of such origin, and hence a generation of a crystal structure was reported to date.
  • 1.5K
  • 16 Aug 2021
Topic Review
Intellectual Capital and Technological Innovation
It is not assumed that intellectual capital is significantly associated with technological innovation. Most of the time, intellectual capital promotes technological innovation, but that is not the whole truth. At some point, some elements of intellectual capital can also have a negative impact on innovation.
  • 1.5K
  • 07 Dec 2021
Topic Review
Potential Seaweed-Derived Bioactive Compounds for Pharmaceutical Applications
Seaweeds have been consumed as whole food since ancient times and used to treat several diseases. Nowadays, seaweeds are widely involved in biotechnological applications. Due to the variety of bioactive compounds in their composition, species of phylum Ochrophyta, class Phaeophyceae, phylum Rhodophyta and Chlorophyta are valuable for the food, cosmetic, pharmaceutical and nutraceutical industries. Research has demonstrated that those unique compounds express beneficial properties for human health. Each compound has peculiar properties (e.g., antioxidant, antimicrobial, antiviral activities, etc.) that can be exploited to enhance human health. Seaweed’s extracted polysaccharides are already involved in the pharmaceutical industry, with the aim of replacing synthetic compounds with components of natural origin. 
  • 1.5K
  • 28 Feb 2022
Topic Review
Astrocytes in Depression and Alzheimer’s Disease
Astrocytes play a key role in the functioning of neurons in norm and pathology, being a target for stress and glucocorticoids, are a promising target for the treatment of stress-dependent depression and Alzheimer’s disease (AD). Depression, as a mental disorder, is characterized by two core symptoms, depressed mood and loss of interest or pleasure in nearly all activities, and may be accompanied by other symptoms such as cognitive impairments, sleep disturbance, psychomotor retardation or agitation, feelings of worthlessness or excessive or inappropriate guilt.
  • 1.5K
  • 20 May 2022
Topic Review
Magnetoencephalography (MEG) and Its Clinical Applications
MEG has two clinical applications, i.e., localization of epileptic foci and pre-operative evaluation for brain surgery candidates. MEG is also an important neuroimaging tool for the therapeutic planning of several mental disorders and abnormality analysis such as epilepsy, autism, schizophrenia, stroke, head trauma, and monitoring of drug administration
  • 1.5K
  • 27 Jun 2022
Topic Review
CHICKEN (Scheme Implementation)
CHICKEN is a compiler and interpreter for the Scheme programming language that compiles Scheme code to standard C. It is mostly R5RS compliant and offers many extensions to the standard. The newer R7RS standard is supported through an extension library. CHICKEN is free software available under the BSD license. It is implemented mostly in Scheme, with some parts in C for performance or to make embedding into C programs easier.
  • 1.5K
  • 14 Oct 2022
Topic Review
Design, Construction and Maintenance of Green Roofs
Urbanisation affects the water cycle and heat balance in a negative way. Vegetated roofs have the potential to minimise the effects of urbanisation. Converting concrete and tiles roofs into green roofs can increase green urban areas and has the potential to reverse such effects, so the design, construction and maintenance of green roofs are very important.
  • 1.5K
  • 20 Oct 2022
Topic Review
History of Infectious Diseases and Medicine
From ancient times to the present, mankind has experienced many infectious diseases, which have mutually affected the development of society and medicine: (1) Classical Western medicine pioneered by Hippocrates and Galen without the concept of infectious diseases (ancient times to 15th century); (2) traditional Western medicine expanded by the publication of printed medical books and organized medical education (16th to 18th century); (3) early modern medicine transformed by scientific research, including the discovery of pathogenic bacteria (19th century); (4) late modern medicine, suppressing bacterial infectious diseases by antibiotics and elucidating DNA structure as a basis of genetics and molecular biology (20th century, prior to the 1980s); and (5) exact medicine saving human life by in vivo visualization and scientifically verified measures (after the 1990s).
  • 1.5K
  • 11 Nov 2022
Topic Review
Soyuz TMA-20
Soyuz TMA-20 was a human spaceflight to the International Space Station (ISS) and was part of the Soyuz programme. It lifted off from the Baikonur Cosmodrome in Kazakhstan on December 15, 2010, and docked with the ISS two days later. The three-person crew of Soyuz TMA-20 – Dmitri Kondratyev, Catherine Coleman and Paolo Nespoli – represented the ISS partner organizations of Roscosmos, NASA and the European Space Agency (ESA). Soyuz TMA-20's crew represented half of the members of Expedition 27; the other three members of the expedition arrived at the station on board Soyuz TMA-21 on April 6, 2011. The COSPAR ID of Soyuz TMA-20 was 2010-067A. It is ISS flight 25S. On May 24, 2011, after spending 159 days in space, the Soyuz TMA-20 descent module landed safely in Zhezkazgan, Kazakhstan, carrying Kondratyev, Coleman and Nespoli.
  • 1.5K
  • 17 Nov 2022
Topic Review
Al-Abid
The Al-Abid(Arabic: العابد) LV was an Iraqi three-stage "Satellite launch system", a civilian project that was commenced in 1988. The Iraqis intended to launch an Al-Ta'ir satellite with the help of such a launch vehicle. The Iraqis therefore pursued a LV with stages based on Scud missiles and the S-75 Dvina. However only the first stage could be tested on December 1989 and according to General Ra'ad the next stages could not be developed. General Ra'ad says that not even the drawings of the second and third stage vehicles are available and that no final report could be produced. UN inspectors and U.S intelligence did not offer many details regarding the Al-Abid launch vehicle as they were not interested in it.
  • 1.5K
  • 29 Nov 2022
Topic Review
Recyclable Products Classification
Effective waste management and recycling are essential for sustainable development and environmental conservation. It is a global issue around the globe and emerging in Saudi Arabia. The traditional approach to waste sorting relies on manual labor, which is both time-consuming, inefficient, and prone to errors.
  • 1.5K
  • 07 Aug 2023
Topic Review
Bali Jatra: The Beautiful Marine History of Odisha
Bali Jatra, a vibrant and culturally rich festival celebrated in Odisha, India, is a tribute to the state’s glorious maritime history. Held annually in Cuttack along the banks of the Mahanadi River, this festival commemorates the ancient sea trade of the Sadhabas (Odia sailors) with Southeast Asian countries like Bali, Java, and Sumatra. Beyond its historical significance, Bali Jatra is a celebration of Odisha's art, craft, and culinary traditions, attracting visitors from across the globe. This article delves into the origins, historical context, cultural festivities, and contemporary significance of Bali Jatra, showcasing it as a symbol of Odisha’s maritime pride and heritage.
  • 1.5K
  • 21 Nov 2024
Topic Review
Bioactivities and Chemical Analysis of Ailanthus altissima(Mill.) Swingle
Many species of the so-called exotic plants coexist with native species in a balanced way, but others thrive very quickly and escape human control, becoming harmful—these are called invasive alien species. In addition to overcoming geographic barriers, these species can defeat biotic and abiotic barriers, maintaining stable populations. Ailanthus altissima is no exception; it is disseminated worldwide and is considered high risk due to its easy propagation and resistance to external environmental factors. Currently, it has no particular use other than ornamental, even though it is used to treat epilepsy, diarrhea, asthma, ophthalmic diseases, and seborrhoea in Chinese medicine. Considering its rich composition in alkaloids, terpenoids, sterols, and flavonoids, doubtlessly, its use in medicine or other fields can be maximised.
  • 1.5K
  • 17 Dec 2021
Topic Review
Asthma
Asthma is an inflammatory condition of the bronchial mucosa affecting 10% of children and 5% of adults in Western countries.
  • 1.5K
  • 25 Apr 2021
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