5 research outputs found
Table_1_Differential influences of serum vitamin C on blood pressure based on age and sex in normotensive individuals.docx
AimHypertension is among the most prevalent chronic diseases with diverse etiology, affecting over 1 billion people globally. In numerous studies, vitamin C inversely correlated with blood pressure and was suspected to have antihypertensive properties. Currently, there is conflicting evidence regarding the relationship between vitamin C and blood pressure, with most studies being conducted on hypertensive subjects. The principal objective of this project was to investigate the relationship between vitamin C and blood pressure in normotensive adult subjects.MethodsA total of 2,533 individuals aged 20 years and above were enrolled in the present study from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. Outcome variables were systolic blood pressure (SBP) and diastolic blood pressure (DBP). Serum vitamin C was regarded as an independent variable. EmpowerStats software and R (version 3.4.3) were used to examine the association between vitamin C and SBP or DBP.ResultsVitamin C was reversely correlated with both SBP (β = −0.02, 95% CI: −0.03 to −0.00, p = 0.0306) and DBP (β = −0.02, 95% CI: −0.04 to −0.01, p = ConclusionVitamin C was negatively correlated with both SBP and DBP in this cross-sectional analysis. However, a U-shaped relationship and an inverted one were also observed in certain people, which implied that, though vitamin C is considered a vital antioxidant, maintaining vitamin C at appropriate levels may be beneficial according to different populations.</p
Efficient and highly selective cyclization induced by Lewis acid to generate 2-hydroxyl-α-cyclogeraniol
<p>A cyclization reaction of the hydroxyl-protected geraniol epoxide induced by the different Lewis acids to generate 2-hydroxyl-α-cyclogeraniol has been explored. Compared with the previous methods, this method enhances the production and selectivity of this reaction without the consumption of a large amount of solvent. Also, the coordination of the metal with two oxygen atoms of hydroxyl groups might be crucial for the reaction is first addressed.</p
Microwave Assisted Tandem Heck–Sonogashira Reactions of <i>N,N</i>-Di-Boc-Protected 6‑Amino-5-iodo-2-methyl Pyrimidin-4-ol in An Efficient Approach to Functionalized Pyrido[2,3‑<i>d</i>]Pyrimidines
A microwave
assisted tandem Heck–Sonogashira cross-coupling
reaction between 6-<i>N,N</i>-di-Boc-amino-5-iodo-2-methyl
pyrimidin-4-ol and various aryl alkynyl substrates has been developed.
This process generates novel 5-enynyl substituted pyrimidines, which
can be transformed to novel functionalized pyridoÂ[2,3-<i>d</i>]Âpyrimidines by way of a silver catalyzed cyclization reaction
Direct Arylation of Benzyl Ethers with Organozinc Reagents
A novel CÂ(sp<sup>3</sup>)–H bond arylation of benzyl ethers
with Knochel-type arylzinc reagents has been developed. This transition-metal-catalyst-free
reaction proceeds well under mild conditions in a simple and effective
manner and enables the synthesis of a wide range of potentially biologically
active benzyl ethers by using highly functionalized organozinc reagents
as a carbon nucleophile
Monitoring and Control of an Adsorption System Using Electrical Properties of the Adsorbent for Organic Compound Abatement
Adsorption
systems typically need gas and temperature sensors to
monitor their adsorption/regeneration cycles to separate gases from
gas streams. Activated carbon fiber cloth (ACFC)–electrothermal
swing adsorption (ESA) is an adsorption system that has the potential
to be controlled with the electrical properties of the adsorbent and
is studied here to monitor and control the adsorption/regeneration
cycles without the use of gas and temperature sensors and to <i>predict</i> breakthrough before it occurs. The ACFC’s
electrical resistance was characterized on the basis of the amount
of adsorbed organic gas/vapor and the adsorbent temperature. These
relationships were then used to develop control logic to monitor and
control ESA cycles on the basis of measured resistance and applied
power values. Continuous sets of adsorption and regeneration cycles
were performed sequentially entirely on the basis of remote electrical
measurements and achieved ≥95% capture efficiency at inlet
concentrations of 2000 and 4000 ppm<sub>v</sub> for isobutane, acetone,
and toluene in dry and elevated relative humidity gas streams, demonstrating
a novel cyclic ESA system that does not require gas or temperature
sensors. This contribution is important because it reduces the cost
and simplifies the system, predicts breakthrough before its occurrence,
and reduces emissions to the atmosphere