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2022 ◽  
Vol 23 (2) ◽  
pp. 709
Author(s):  
Agata Gabryelska ◽  
Szymon Turkiewicz ◽  
Filip Franciszek Karuga ◽  
Marcin Sochal ◽  
Dominik Strzelecki ◽  
...  

Obstructive sleep apnea (OSA) is a chronic condition characterized by recurrent pauses in breathing caused by the collapse of the upper airways, which results in intermittent hypoxia and arousals during the night. The disorder is associated with a vast number of comorbidities affecting different systems, including cardiovascular, metabolic, psychiatric, and neurological complications. Due to abnormal sleep architecture, OSA patients are at high risk of circadian clock disruption, as has been reported in several recent studies. The circadian clock affects almost all daily behavioral patterns, as well as a plethora of physiological processes, and might be one of the key factors contributing to OSA complications. An intricate interaction between the circadian clock and hypoxia may further affect these processes, which has a strong foundation on the molecular level. Recent studies revealed an interaction between hypoxia-inducible factor 1 (HIF-1), a key regulator of oxygen metabolism, and elements of circadian clocks. This relationship has a strong base in the structure of involved elements, as HIF-1 as well as PER, CLOCK, and BMAL, belong to the same Per-Arnt-Sim domain family. Therefore, this review summarizes the available knowledge on the molecular mechanism of circadian clock disruption and its influence on the development and progression of OSA comorbidities.


2022 ◽  
pp. 151-175
Author(s):  
W. Trent Bunderson ◽  
Christian L. Thierfelder ◽  
Zwide D. Jere ◽  
R. G. K. Museka

Abstract The Conservation Agriculture (CA) system promoted by Total LandCare (TLC) and the International Maize and Wheat Improvement Center (CIMMYT) is based on 14 years of experience grounded on the principles of minimum soil disturbance, good soil cover and crop associations. The platform to promote CA in Malawi was to build a strong base of knowledge about best practices through an innovative non-linear research-extension approach. Long-term on-farm trials were conducted in multiple sites across Malawi to compare yields and labour inputs of CA with conventional ridge tillage on the same footing. Results showed the superiority of CA in terms of maize and legume yields with significant savings in labour and resilience to climate change. The results provided the basis to upscale CA although adoption was lower than expected. Key challenges included: (i) lack of exposure and training; (ii) conflicting extension messages; (iii) misconceptions about inputs and tools for CA; (iv) resistance to change unless CA is clearly seen to be a better practice; (v) fears about controlling weeds, pests and diseases under CA; and (vi) perceptions that increased termites and earthworms are harmful to soils and crops.


2022 ◽  
Author(s):  
Yasuhiro Yamashita

Chiral alkaline metal Brønsted bases are traditional and reliable promoters in enantioselective catalysis. Here, new chiral potassium strong base catalysts were developed for enantioselective carbon–carbon bond-forming reactions of weakly acidic...


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Miguel Arocena

Abstract What happens at the very beginning of the titration of a weak acid or base is a question sometimes asked by undergraduate students when introduced to the concept of buffer solution. To attempt to answer this question, a simple quantitative approach is developed, which also allows explaining more general properties of the weak acid or weak base titration process, while serving as well as an introduction to the theoretical, quantitative treatment of this subject. Using this approach, it can be shown that, at the beginning of the titration, the reaction between a weak acid (base) and a strong base (acid) does not occur on a one to one ratio when very small amounts of the strong base (acid) are added.


Molecules ◽  
2021 ◽  
Vol 26 (24) ◽  
pp. 7690
Author(s):  
Robert Alan Aitken ◽  
Andrew D. Harper ◽  
Alexandra M. Z. Slawin

Three isomeric (benzyloxythienyl)oxazolines 9, 11 and 13 have been prepared and are found, upon treatment with a strong base, to undergo either Wittig rearrangement or intramolecular attack of the benzylic anion on the oxazoline function to give products derived from cleavage of the initially formed 3-aminothienofuran products. This pattern of reactivity is directly linked to the distance between the two reactive groups as determined by X-ray diffraction, with the greatest distance in 11 leading to exclusive Wittig rearrangement, the shortest distance in 13 giving exclusively cyclisation-derived products, and the intermediate distance in 9 leading to both processes being observed. The corresponding N-butyl amides were also obtained in two cases and one of these undergoes efficient Wittig rearrangement leading to a thieno[2,3-c]pyrrolone product.


Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8097
Author(s):  
Tomasz Jałowiec ◽  
Henryk Wojtaszek ◽  
Ireneusz Miciuła

The EU’s energy policy is geared towards introducing changes in order to stop or avoid negative climate change. The determinants of the energy policies of Poland and Germany are presented along with the priorities until 2050. The possibilities of reducing the impact of energy on the environment were interpreted, emphasizing its common goal. Activities supporting the EU and maintaining the level of energy security are indicated. Possible negative effects in the social and health sphere are presented as a response to the failure to implement these demands. The literature was analyzed and proprietary questionnaires were carried out, and the results realized in the EU by the independent FBI Economic Department were implemented. On the basis of earlier pilot studies, variants of a successful transformation were implemented, assuming different roles performed by a citizen (entrepreneur). Opportunities to tackle climate change and global challenges have been identified based on innovation and motivation. The opinion on the way of thinking in Poland and Germany was compared, and a descriptive model was prepared to increase the achievement of the assumed goals, together with a model based on innovation. Citizens should be active in efforts to promote renewable energy. The EU has a strong base to work to avoid climate change. What is needed is innovative thinking and a motivation to introduce changes with the involvement of every citizen through solidarity, efficiency, and justice. The existing foundations of legal solutions create adaptation possibilities and the ability to achieve goals through self-discipline, comparing with the assumption of EU civic awareness, significantly affecting the successful implementation of RES. Analyzing the attitudes of Poland and Germany, it seems that the distant social consequences are not sufficient. It is necessary not only to perform selected management functions (planning, organizing), but also partly to motivate. There is a strong need to increase motivation and implement the control process required under the threat of negative consequences in the current period as a key strategic preventive action. The analysis of the opinions of Poland and Germany against the background of the European Union allowed for no significant differences, subject to Germany’s readiness to take greater risk. Most of Poland is less inclined to take risks. The lack of an unambiguous opinion may indicate incomplete awareness of both the negative effects of climate change. Both countries are concerned about the unplanned costs of transformation. Germany, unlike Poland, has dedicated employees to handle the climate, and conducts an energy audit and is of interest to investors, thanks to investment plans.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xavier Foster ◽  
Céline Vaneeckhaute

AbstractIn order to avoid eutrophication of freshwater systems, regulations all around the world have become increasingly stringent toward the maximum phosphate concentration allowed in wastewater discharges. Traditional phosphate removal methods such as chemical precipitation and enhanced biological phosphorus removal struggle to lower phosphate levels to the new requirements. Hybrid anion exchange nanotechnology (HAIX-Nano) is composed of a selective adsorption material able to remove phosphate down to levels close to zero. Moreover, HAIX-Nano is not affected by intermittent flow and does not produce sludge making it an interesting alternative. The regeneration process of HAIX-Nano typically requires a chemical solution with a high concentration of sodium hydroxide (NaOH) and sodium chloride (NaCl) (2–5% w/w of each). To lower the environmental impact and the operational cost of the technology, this study aims to enhance the HAIX-Nano regeneration efficiency. Therefore, the backbone of HAIX-Nano, which is normally a strong base anionic (SBA) resin, was changed for a weak base anionic (WBA) resin. The resulting material (WBA-2) exhibited a higher adsorption capacity than the traditional version of HAIX-Nano (SBA-1) under the tested conditions, while also showing a much higher regeneration efficiency. For a desorption solution of only 0.4% NaOH and no NaCl, WBA-2 showed an average regeneration efficiency of 78 ± 1% compared to SBA-1 with 24 ± 1%.


2021 ◽  
Vol 17 (1) ◽  
pp. 127-134
Author(s):  
Hong Hua Lim ◽  
Fei Ling Pua ◽  
R. Othman ◽  
Yun Hin Taufiq-Yap ◽  
Shamala Gowri Krishnan

In this paper, solid base catalyst KF/CLW-Fe3O4 was prepared from carbide lime waste, primarily calcium hydroxide with tiny amounts of carbonate and; the catalyst was used in the optimization study on the methyl ester production. The new strong base catalyst was synthesized by chemical impregnation. This catalyst was characterized by Hammett indicator analysis, Brunauer, Emmett, and Teller (BET), scanning electron microscope (SEM), X-ray diffraction (XRD) and temperature-programmed desorption (TPD) of carbon dioxide. The catalyst was further used to catalyzed the transesterification reaction to produce methyl ester. Taguchi method was used to assess the impact of catalyst at different intervals of reaction parameters, including reaction time, methanol to oil ratio, and catalyst loading. A mixed level of orthogonal array design with L9, analysis of variance (ANOVA) and signal to noise ratio were used to determine parameters that significantly impact the palm oil transesterification reaction. High methyl ester conversion was attained, and the catalyst can be easily separated and reused. KF/CLW-Fe3O4 has great potential to be used to produce methyl ester because of its high catalytic activity and environmental friendliness. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 


2021 ◽  
Author(s):  
Lan Shang ◽  
Christophe Hoareau ◽  
Andreas Zilian

AbstractAn electromechanical model for beam-like piezoelectric energy harvesters based on Reissner’s beam theory is developed in this paper. The proposed model captures first-order shear deformation and large displacement/rotation, which distinguishes this model from other models reported in the literature. All governing equations are presented in detail, making the associated framework extensible to investigate various piezoelectric energy harvesters. The weak formulation is then derived to obtain the approximate solution to the governing equations by the finite element method. This solution scheme is completely coupled, and thus allows for two-way interaction between mechanical and electrical fields. To validate this model, extensive numerical examples are implemented in the linear and nonlinear regime. In the linear limit, this model produces results in excellent agreement with reference data. In the nonlinear regime, the large amplitude response of the piezoelectric beam induced by strong base excitation or fluid flow is considered, and the comparison of results with literature data is encouraging. The ability of this nonlinear model to predict limit cycle oscillations in axial flow is demonstrated.


Author(s):  
Michael Talhami ◽  
Mark Zeitoun

Abstract This article investigates the effects that attacks during armed conflict which damage water and wastewater services have on the outbreak and transmission of infectious disease. It employs a lens of uncertainty to assess the level of knowledge about the reverberations along this consequential chain and to discuss the relevance to military planning and targeting processes, and to the laws of armed conflict. It draws on data in policy reports and research from a wide variety of contexts, and evidence from protracted armed conflicts in Iraq, Yemen and Gaza. The review finds a strong base of evidence of the impact of attacks on water and wastewater services, and a high level of confidence in information about the transmission of infectious disease. One clear risk identified is when people are exposed to water supplies which are contaminated by untreated wastewater. Obtaining a similar level of confidence about the cause and effect along the full consequential chain is challenged by numerous compounding variables, though there are a number of patterns related to the duration of the armed conflict within which the attacks occur. As the conflict protracts, both the risk of the spread of infectious disease and the evidence base for gauging the reverberating effects becomes stronger, for example. The article concludes that the reverberating effects of damage from an attack can be foreseen in some contexts and can be expected to become more foreseeable over time. The analysis suggests that the most pragmatic path for military institutions and those involved in targeting operations to take this knowledge into account is through a “precautionary approach” which assumes the existence of the reverberating effects, and works them in to the standard information-gathering and planning processes.


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