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Topic Review
Electroreduction of CO2 toward High Current Density
Carbon dioxide (CO2) electroreduction offers an attractive pathway for converting CO2 to valuable fuels and chemicals. Despite the existence of some excellent electrocatalysts with superior selectivity for specific products, these reactions are conducted at low current densities ranging from several mA cm−2 to tens of mA cm−2, which are far from commercially desirable values. To extend the applications of CO2 electroreduction technology to an industrial scale, long-term operations under high current densities (over 200 mA cm−2) are desirable.
  • 1.6K
  • 05 May 2022
Topic Review
Internet Taxes
In 1996, several U.S. states and municipalities began to see Internet services as a potential source of tax revenue. The 1998 Internet Tax Freedom Act halted the expansion of direct taxation of the Internet, grandfathering existing taxes in ten states. In the United States alone, some 30,000 taxing jurisdictions could otherwise have laid claim to taxes on a piece of the Internet. The law, however, did not affect sales taxes applied to online purchases. These continue to be taxed at varying rates depending on the jurisdiction, in the same way that phone and mail orders are taxed.
  • 1.6K
  • 26 Oct 2022
Topic Review
History of Web Syndication Technology
Web syndication technologies were preceded by metadata standards such as the Meta Content Framework (MCF) and the Resource Description Framework (RDF), as well as by 'push' specifications such as Channel Definition Format (CDF). Early web syndication standards included Information and Content Exchange (ICE) and RSS. More recent specifications include Atom and GData.
  • 1.6K
  • 09 Nov 2022
Topic Review
Primary Life Support System
A Primary (or Portable or Personal) Life Support System (or Subsystem) (PLSS), is a device connected to an astronaut or cosmonaut's spacesuit, which allows extra-vehicular activity with maximum freedom, independent of a spacecraft's life support system. The PLSS is generally worn like a backpack. The functions performed by the PLSS include: The air handling function of a PLSS is similar to that of a diving rebreather, in that exhaled gases are recycled into the breathing gas in a closed loop. When used in a microgravity environment, a separate propulsion system is generally needed for safety and control, since there is no physical connection to a spacecraft.
  • 1.6K
  • 11 Nov 2022
Topic Review
RSA BSAFE
RSA BSAFE is a FIPS 140-2 validated cryptography library, available in both C and Java, offered by RSA Security. It was one of the most common ones before the RSA patent expired in September 2000. It also contained implementations of the RCx ciphers, with the most common one being RC4. From 2004 to 2013 the default random number generator in the library was a NIST-approved RNG standard, widely known to be insecure from at least 2006, withdrawn in 2014, suspected to contain an alleged kleptographic backdoor from the American National Security Agency (NSA), as part of its secret Bullrun program.
  • 1.6K
  • 25 Nov 2022
Topic Review
Young Employees’ Perceptions about Employability Skills for E-Commerce
With the digital transformation of businesses, digital marketing has been a prominent feature of organizations in the 21st century. Changing consumer behavior has also created a need for versatile hard and soft skills for marketing professionals. Given the dynamic growth of the e-commerce market and the trends mentioned above, it is expected that the needs of the labor market will also change. University education aims to develop key competences. Understanding which competences are considered important could improve the motivation of students. 
  • 1.6K
  • 19 Dec 2022
Topic Review
Cardiothoracic Surgical Critical Care Medicine
Cardiothoracic surgical critical care medicine (CT-CCM) is a medical discipline centered on the perioperative care of diverse groups of patients. With an aging demographic and an increase in burden of chronic diseases the utilization of cardiothoracic surgical critical care units is likely to escalate. Given these projections, it is important to assess the state of cardiothoracic surgical intensive care, to develop goals and objectives for the future, and to identify knowledge gaps in need of scientific inquiry.
  • 1.6K
  • 09 Jan 2023
Topic Review
Evolutionary Progress of Silica Aerogels
Aerogels are highly porous materials with fascinating properties prepared using sol-gel chemistry. Due to their unique physical and chemical properties, aerogels are recognized as potential candidates for diverse applications, including thermal insulation, sensor, environmental remediation, etc. Despite these applications, aerogels are not routinely found in our daily life because they are fragile and have highly limited scale-up productions. It remains extremely challenging to improve the mechanical properties of aerogels without adversely affecting their other properties. To boost the practical applications, it is necessary to develop efficient, low-cost methods to produce aerogels in a sustainable way.
  • 1.6K
  • 22 May 2023
Topic Review
Types of Mesenchymal Stem Cells from Oral Cavity
Adult mesenchymal stem cells are those obtained from the conformation of dental structures (DMSC), such as deciduous and permanent teeth and other surrounding tissues. 
  • 1.6K
  • 21 Nov 2023
Topic Review
Hydrogen Production Methods
Numerous environmental problems, which include global warming, acid rain, and stratospheric ozone depletion, have been brought on by the transformation, production, and consumption of energy. The quest for a substitute and more efficient sources of energy has been prompted by the potential scarcity of fossil fuels and concerns about the environment. The energy carrier hydrogen (H2) seems to have a lot of potential for significantly contributing to increased sustainability and environmental performance. Despite the fact that tackling future energy problems calls for a variety of strategies, many believe H2 will play a significant role, in part because it does not produce greenhouse gases when it is oxidised.
  • 1.6K
  • 06 Dec 2023
Topic Review
Cardiac Morphogenesis
MicroRNAs represent the most studied subtype of small non-coding RNAs. microRNAs display temporal and spatial differential expression in both embryonic and adult tissues, contributing thus to both embryonic development and tissue homeostasis. Long non-coding RNAs also display tissue-specific expression during embryogenesis and tissue homeostasis, being their role in pathology also emerging.
  • 1.6K
  • 18 Mar 2022
Topic Review
CO2 Pneumoperitoneum
Laparoscopy (LS) has been shown to decrease the inflammatory sequelae of endotoxemia. β-arrestin 2 plays an important function in signal transduction pathway of TLR4. High mobility group box-1 (HMGB-1) is involved in the delayed systemic inflammatory response. We investigated the effects of CO2 insufflation on liver, lung, and kidney expression of both β-arrestin 2 and HMGB-1 during sepsis. Cecal ligation and puncture (CLP) was performed in male rats and 6 h later the animals were randomly assigned to receive a CO2 pneumoperitoneum or laparotomy. Animals were euthanized; liver, lung, and kidney were removed for the evaluation of β-arrestin 2 and HMGB-1 expression. Immunohistochemical detection of myeloperoxidase (MPO) was investigated in lung and liver and bacterial load was determined in the peritoneal fluid. CO2 pneumoperitoneum reduced peritoneal bacterial load, increased the expression of β-arrestin 2, and blunted the expression of the potent proinflammatory HMGB-1 in liver, lung, and kidney compared with laparotomy. Liver and lung MPO was markedly reduced in rats subjected to LS compared with laparotomy. We believe that CO2 exerts an early protective effect by reducing bacterial load and likely toll-like receptor activation which in turn leads to a preserved β-arrestin 2 expression and a reduced HMGB-1 expression.
  • 1.6K
  • 02 Nov 2020
Topic Review
Cytokinins in Plant
Cytokinins (CKs) are key phytohormones that not only regulate plant growth and development but also mediate plant tolerance to drought stress. Recent advances in genome-wide association studies coupled with in planta characterization have opened new avenues to investigate the drought-responsive expression of CK metabolic and signaling genes, as well as their functions in plant adaptation to drought. Under water deficit, CK signaling has evolved as an inter-cellular communication network which is essential to crosstalk with other types of phytohormones and their regulating pathways in mediating plant stress response. In this review, we revise the current understanding of CK involvement in drought stress tolerance. Particularly, a genetic framework for CK signaling and CK crosstalk with abscisic acid (ABA) in the precise monitoring of drought responses is proposed. In addition, the potential of endogenous CK alteration in crops towards developing drought-tolerant crops is also discussed.
  • 1.6K
  • 28 Oct 2020
Topic Review
Seed Banking Effectiveness
Understanding seed viability under long-term storage conditions provides basic and useful information to investigate the effectiveness of seed banking. Besides the germination success, seedling establishment is also an important requirement, and a decisive step to ensure plant propagation. We used comparative data of germination, seedling growth, and survival percentage between fresh and 10-years-stored seeds of Senecio morisii, a narrow endemic and vulnerable species of Sardinia (Italy), in order to evaluate if differences exist in these traits. Stored seeds showed higher germination percentages than fresh ones, whereas seedling growth and survival did not present significant differences between them, except for seedling growth in plants produced from seeds germinated at 25 °C. This study allowed us to assess if seeds of S. morisii were able to germinate under controlled conditions, and if they maintained their viability and germination capacity for at least 10 years of long-term storage in the seed bank. In addition, the high seedling survival detected in both fresh and stored seeds suggests that stored seeds of S. morisii can be used to support reinforcement or reintroduction actions when fresh materials are not available.
  • 1.6K
  • 30 Oct 2020
Topic Review
Fortification
Large-scale food fortification is an effective, sustainable, and scalable intervention to address vitamin and mineral deficiencies, however, pressing gaps exist globally around ensuring the quality of fortified foods. This paper summarizes the global challenges and gaps faced in monitoring the quality of fortified foods, the guidance produced in response to these challenges, where we are today in terms of effective implementation, and what approaches and opportunities may be usefully applied to enhance the quality of fortified foods moving forward.
  • 1.6K
  • 14 Jan 2021
Topic Review
Lycium barbarum Polysaccharides
The fruit of Lycium barbarum L. (goji berry) is used as traditional Chinese medicine, and has the functions of immune regulation, anti-tumor, neuroprotection, anti-diabetes, and anti-fatigue. One of the main bioactive components is L. barbarum polysaccharide (LBP). 
  • 1.6K
  • 25 Apr 2021
Topic Review
Circularly Polarized Hybrid DR Antennas
It has been a feasible approach to build an antenna, in view of the potential advantages they offer. One of the recent trends in dielectric resonator antenna research is the use of compound and hybrid structures. Several considerable investigations have been already underway showing quite interesting and significant features in bandwidth, gain, and generation of circular polarization. 
  • 1.6K
  • 28 Jun 2021
Topic Review
Newborn and Child Health
Home-based records are paper or electronic records retained and used by mothers or caregivers to document the health services received for maternal, newborn, and child health. Little has been studied about the roles of these records on newborn and child health outcomes.
  • 1.6K
  • 29 Jul 2021
Topic Review
Food Insecurity Is Associated with Cognitive Function
Food insecurity (FI) has negative implications across the life course that include poor health outcomes among both children and adults. However, the behavioral mechanisms by which FI impacts health behaviors are not clear. 
  • 1.6K
  • 25 Nov 2021
Topic Review
Ghana’s Potentials in Solar Energy Generation and Development
The future of Ghana’s solar industry seems promising considering the recent add-ons in the sector. Solar has seen various faces of transformation in Ghana, despite major setbacks such as intermittency and volatility. Currently, solar has become the most popular renewable energy source in Ghana and has great viability especially if the future security needs of the country are to be considered. It is undeniable that Ghana’s energy sector has a promising future if favorable policies are carved to promote solar technology. It is also worthy to note that electricity from solar PVs has gained a lot of prominence and attention in various economies across the world partly due to the general drop in the production cost. This has made it relatively competitive to consider against other counterparts such as wind and hydro. Ghana’s solar energy generation potentials are enormous, considering the amount of sunlight received. Governments have kept the drive to improve electrification across the length and breadth of the country which to a large extent, has been successful with about 82.4% of the population having access to electricity. Previously, Ghana was locked in to the use of hydropower for electrification but recent competitive prices in solar PVs have gradually inspired the desire for utility and off-grid solar systems among the general populace. Various data gathered over the past 50 years by Ghana Meteorological Agency (GMA) and other authoritative bodies suggests that the amount of sunshine received in the various regions across the country is more than enough to generate the radiation needed for solar PV’s to function to capacity with a potential error in radiation at +/−5%. The initial increase in solar was a result of various projects pushed across by the Ghana Energy Access and Development Project (GEDAP) funded by a host of donors. Several campaigns have been made to push solar such as the “200 MW Government Goes Solar” by the Energy Commission with the sole aim of distributing free solar panels with up to 500 W capacity to especially off-grid remote communities in 2018. Indeed, it can be said that various solar projects are underway to augment the current energy sources in Ghana especially as the government is determined to uphold the renewable energy target of 10% by the year 2020.
  • 1.6K
  • 19 Jan 2022
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