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Topic Review

Sina Weibo (NASDAQ: WB) (新浪微博) is a Chinese microblogging (weibo) website. Launched by Sina Corporation on 14 August 2009, it is one of the biggest social media platforms in China, with over 445 million monthly active users as of Q3 2018. The platform has been a huge financial success, with surging stocks, lucrative advertising sales and high revenue and total earnings per quarter. At the start of 2018, it surpassed the US$30 billion market valuation mark for the first time. In March 2014, Sina Corporation announced a spinoff of Weibo as a separate entity and filed an IPO under the symbol WB. Sina carved out 11% of Weibo in the IPO, with Alibaba owning 32% post-IPO. The company began trading publicly on 17 April 2014. In March 2017, Sina launched Sina Weibo International Version. This new version has a clean, concise user interface design, as well as an ad-free feature; while its volume is very small, only occupying one-fifth of the space of the original, it still performs all of the original's functions. In June 2018, Sina Weibo reached 413 million active users. In November 2018, Sina Weibo suspended its registration function for minors under the age of 14. In July 2019, Sina Weibo announced that it would launch a two-month campaign to clean up pornographic and vulgar information, named The Blue Plan. Sina Weibo has attracted criticism over censoring its users.

8.1K
02 Nov 2022

Topic Review

Induction of Polyploidy

Polyploidy has the utmost importance in horticulture for the development of new ornamental varieties with desirable morphological traits referring to plant size and vigor, leaf thickness, larger flowers with thicker petals, intense color of leaves and flowers, long lasting flowers, compactness, dwarfness and restored fertility. Polyploidy may occur naturally due to the formation of unreduced gametes or can be artificially induced by doubling the number of chromosomes in somatic cells.

8.1K
21 Dec 2021

Topic Review

FN Baby Browning

The 1931 Fabrique Nationale ("FN") Baby Browning Pistol is a small blowback-operated semi-automatic pistol designed by Belgium-born Dieudonné Saive chambered in .25 ACP (6,35mm). The pistol features a six-round magazine capacity and is a striker-fired, single action, blow back mechanism. The manual thumb operated safety locks the slide in the closed position when engaged using side thumb pressure.

8.1K
14 Oct 2022

Topic Review

Pandora Media Inc. (also known as Pandora Internet Radio or simply Pandora) is a music streaming and automated music recommendation internet radio service powered by the Music Genome Project. As of August 1, 2017, the service, operated by Pandora Media, Inc., is available only in the United States. The service plays songs that have similar musical traits. The user then provides positive or negative feedback (as thumbs up or thumbs down) for songs chosen by the service, and the feedback is taken into account in the subsequent selection of other songs to play. The service can be accessed either through a web browser or with its mobile app. Pandora is a freemium service; basic features are free with advertisements or limitations, while additional features, such as improved streaming quality, music downloads and offline channels are offered via paid subscriptions. On September 24, 2018, Sirius XM Holdings announced its intent to acquire Pandora for $3.5 billion.

8.1K
15 Nov 2022

Topic Review

The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly average number of citations of articles published in the last two years in a given journal. It is frequently used as a proxy for the relative importance of a journal within its field; journals with higher impact factor values are often deemed to be more important, or carry more intrinsic prestige in their respective fields, than those with lower values.

8.0K
03 Mar 2023

Topic Review

The SSC Ultimate Aero is a mid-engined sports car that was produced by SSC North America (formerly known as Shelby SuperCars) from 2004 until 2013. The SSC Ultimate Aero held the world production car speed record title, according to the Guinness World Records, from 2007 (when it was officially timed at 410 km/h) until the introduction of the Bugatti Veyron Super Sport in 2010. In April 2013, the Guinness World Records temporarily disqualified the Veyron's record time for a period of five days due to concerns about electronic speed limiting changing the function of the car, but after investigation reinstated the Veyron as the record holder. The SSC Ultimate Aero was not sold with electronic driver aids such as an anti-lock braking system or traction control system, as according to Jerod Shelby (no relations to Carroll Shelby), "Early design philosophy on the car was to make it a driver's car. I wanted a car that you not only throttled with your right foot but at times you could steer with your right foot and a sensor."

8.0K
04 Nov 2022

Topic Review

Transcaucasia, also known as the South Caucasus, is a geographical region on the border of Eastern Europe and Western Asia, straddling the southern Caucasus Mountains. Transcaucasia roughly corresponds to modern Armenia, Georgia and Azerbaijan, and are sometimes collectivelly known as the Caucasian States. The total area of these countries measures about 186,100 square kilometres (71,850 square miles). Transcaucasia and Ciscaucasia (North Caucasus) together comprise the larger Caucasus geographical region that divides Eurasia.

8.0K
23 Nov 2022

Topic Review

DNA Excision Repairs and Implication

The physiological impact of the aberrant oxidation products on genomic DNA were demonstrated by embryonic lethality or the cancer susceptibility and/or neurological symptoms of animal impaired in the base excision repair (BER); the major pathway to maintain genomic integrity against non-bulky DNA oxidation. However, growing evidence suggests that other DNA repair pathways or factors that are not primarily associated with the classical BER pathway are also actively involved in the mitigation of oxidative assaults on the genomic DNA, according to the corresponding types of DNA oxidation. Among others, factors dedicated to lesion recognition in the nucleotide excision repair (NER) pathway have been shown to play eminent roles in the process of lesion recognition and stimulation of the enzyme activity of some sets of BER factors. Besides, substantial bulky DNA oxidation can be preferentially removed by a canonical NER mechanism; therefore, loss of function in the NER pathway shares common features arising from BER defects, including cancer predisposition and neurological disorders, although NER defects generally are nonlethal.

8.0K
30 Oct 2020

Topic Review

List of ISBN Identifier Groups

This is a list of ISBN identifier groups, the second element in 13-digit ISBNs (the first element in 10-digit ISBNs). The identifier is assigned to mark either a publisher's place of business or the language of the books it publishes. The "original" set of identifiers, assigned prior to the introduction of 13-digit ISBNs and, as such, prior to 978-prefix books, ranged from one to five numerical digits, according to the following structure: They are assigned in approximate descending order of publishing volume. Because the smaller identifiers have room for fewer publishers and ISBNs, several countries have had more than one identifier assigned to them. On the other hand, several countries (Australia, Canada, France, Austria, Switzerland...) have no identifier because they fall in the "language groups". The structure for the identifiers of the 979- prefix and whether it will have language-specific identifiers is not well known, but four identifiers have been assigned (979-10, to France, 979-11, to the Republic of Korea, 979-12, to Italy, and 979-8, to the United States of America). Also, 979-0 has been reserved for the use of International Standard Music Number for sheet music. A 977- prefix indicates International Standard Serial Numbers.

8.0K
28 Oct 2022

Topic Review

Xbox One System Software

The Xbox One system software, sometimes called the Xbox OS, or Xbox Dashboard (when a person is referring to software updates), is the operating system developed exclusively for the Xbox One consoles. It is a Microsoft Windows-based operating system using the Hyper-V virtual machine monitor and contains separate operating systems for games and applications that can run on the console. It is located on the internal HDD for day-to-day usage, while also being duplicated on the internal NAND storage of the console for recovery purposes and factory reset functionality. The Xbox One allows users to download applications that add to the functionality of the dashboard. From June 2014 onwards, entertainment apps no longer required the user to be signed into a valid Xbox Live Gold account in order to use the features advertised for the given app. Since launch, Microsoft has been updating the OS monthly, with updates downloaded from the Xbox Live service directly to the Xbox One and subsequently installed, or by using offline recovery images downloaded via a PC. In November 2015, a major system update known as the New Xbox One Experience was released, which brought very significant changes to the design and functionality of the system. The Windows 10-based Core had replaced the Windows 8-based one in this update, and the new system is sometimes referred to as "Windows 10 on Xbox One".

8.0K
03 Nov 2022

Topic Review

Prajñā (Hinduism)

Pragña or Pragya (Sanskrit: प्रज्ञ) as प्रज्ञा, प्राज्ञ and प्राज्ञा is used to refer to the highest and purest form of wisdom, intelligence and understanding. Pragya is the state of wisdom which is higher than the knowledge obtained by reasoning and inference.

8.0K
25 Oct 2022

Topic Review

A luxury vehicle provides increased levels of comfort, equipment, amenities, quality, performance, and status relative to regular cars for an increased price. The term is subjective and reflects both the qualities of the car and the brand image of its manufacturer. Luxury brands rank above premium brands, though there is no fixed demarcation between the two. Traditionally, most luxury cars were large vehicles, though smaller sports-oriented models were always produced. “Compact“ luxury vehicles such as hatchbacks, and off-road capable sport utility vehicles, are relatively modern trends.

8.0K
27 Oct 2022

Topic Review

List of Mammal Genera

There are currently 1258 genera, 156 families, 28 orders, and around 5937 recognized living species of mammal. Mammalian taxonomy is in constant flux as many new species are described and recategorized within their respective genera and families. The taxonomy represented here is a compilation of the most logical and up-to-date information on mammalian taxonomy from many sources, the main ones being the HMW series and the Mammals Species of the World by Wilson and Reeder.

8.0K
27 Oct 2022

Topic Review

Genome-wide association studies (GWAS)

Genome-wide association studies (GWAS) are studies assessing and analyzing either differences or variations in DNA sequences across the human genome to detect genetic risk factors of diseases prevalent within a target population under study.

8.0K
24 Aug 2020

Topic Review

Brahmacharya (/ˌbrɑːməˈtʃɑːrjə/; Devanagari: ब्रह्मचर्य, Bengali: ব্রহ্মচর্য odia:ବ୍ରହ୍ମଚର୍ଯ୍ୟ lit."pure conduct") is a concept within Indian religions that literally means to stay in conduct within one's own Self. In Yoga, Hinduism and Jainism it generally refers to a lifestyle characterized by sexual continence or complete abstinence. Brahmacharya is somewhat different from the English term "celibacy," which merely means non-indulgence in sexual activity. Brahmacharya is when a person completely controls his body and mind (citta) through ascetic means. In the Hindu, Jain, and Buddhist monastic traditions, brahmacharya implies, among other things, the mandatory renunciation of sex and marriage. It is considered necessary for a monk's spiritual practice. Western notions of the religious life as practiced in monastic settings mirror these characteristics.

8.0K
04 Nov 2022

Topic Review

Electrical Double-Layer Capacitors

Capacitors with superior characteristics (called supercapacitors), which are unavailable in conventional batteries, exhibit excellent functionality in many areas, including power density, charge/discharge cycles, operation over a wide temperature range, and reliability, which have been noted as limits of batteries.

8.0K
08 Jan 2021

Topic Review

Wind turbines (WTs) are large devices utilized to convert the wind's kinetic energy into electricity. There are several different typologies of WTs, the most common type being the so-called Horizontal Axis Wind Turbine (HAWT) systems. In this configuration, the rotation axis of the rotor is parallel to the ground. Specific attention must be paid to the orientation with respect to the wind direction, which is different from other types of wind turbines such as those with a vertical axis (VAWT), whose orientation is independent of the prevailing wind direction. For HAWT, the three-bladed upwind configuration is the most common one, with the rotor facing the incoming wind. WTs can be deployed both on- or offshore and have very different blade lengths, which result in different sizes (especially regarding the tower height) and power output. Due to fatigue and exposure to outdoor elements, WT monitoring and diagnostics are strictly needed to reduce structural and mechanical failure and achieve cost-effective energy production. This requires both the Structural Health Monitoring of the WTs load-bearing components (tower, blades, foundations, etc) and the Condition Monitoring of their mechanical parts (gearbox, generator, etc).

8.0K
02 Mar 2022

Biography

David Tynan O'Mahony (6 July 1936 – 10 March 2005), professionally known as Dave Allen, was an Irish observational comedian[1] and satirist.[2] Initially becoming known in Australia during 1963–64, Allen made regular television appearances in the United Kingdom from the later 1960s and until the mid-1980s. The BBC aired his Dave Allen Show 1972–1986,[3] which was also exported to several

8.0K
15 Nov 2022

Topic Review

Type 3 Diabetes

The exact connection between Alzheimer’s disease (AD) and type 2 diabetes is still in debate. However, poorly controlled blood sugar may increase the risk of developing Alzheimer’s. This relationship is so strong that some have called Alzheimer’s “diabetes of the brain” or “type 3 diabetes (T3D)”. Given more recent studies continue to indicate evidence linking T3D with AD, this state-of-the-art aimed to demonstrate the relationship between T3D and AD based on the fact that both the processing of amyloid-β (Aβ) precursor protein toxicity and the clearance of Aβ are attributed to impaired insulin signaling, and that insulin resistance mediates the dysregulation of bioenergetics and progress to AD.

8.0K
29 Oct 2020

Topic Review

Math 55 is a two-semester long first-year undergraduate mathematics course at Harvard University, founded by Lynn Loomis and Shlomo Sternberg. The official titles of the course are Honors Abstract Algebra (Math 55a) and Honors Real and Complex Analysis (Math 55b). Previously, the official title was Honors Advanced Calculus and Linear Algebra.

8.0K
03 Nov 2022

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