scholarly journals Simultaneous and Efficient Production of Furfural and Subsequent Glucose in MTHF/H2O Biphasic System via Parameter Regulation

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 557
Author(s):  
Shaolong Sun ◽  
Xuefei Cao ◽  
Huiling Li ◽  
Yingbo Zhu ◽  
Yijing Li ◽  
...  
Keyword(s):  
Glucose Production ◽  
Biphasic System ◽  
Efficient Production ◽  
Obvious Effect ◽  
Environment Friendly ◽  
H2so4 Concentration ◽  
Food Industries ◽  
The Difference ◽  
Temperature Time ◽  
Furfural Production

Efficient production of furfural from cornstalk in 2-Methyltetrahydrofuran/aqueous (MTHF/H2O) biphasic system via parameter regulation (e.g., VMTHF/VH2O, temperature, time, and H2SO4 concentration) was proposed. The resulting solid residues achieved from the different MTHF/H2O system conditions for furfural production were also to prepare glucose by adding cellulases to increase the high-value applications of cornstalk. A maximum furfural yield (68.1%) was obtained based on reaction condition (VMTHF:VH2O = 1:1, 170 °C, 60 min, 0.05 M H2SO4). Among these parameters, the concentration of H2SO4 had the most obvious effect on the furfural production. The glucose yields of the residues acquired from different MTHF/H2O processes were enhanced and then a maximum value of 78.9% based on the maximum furfural production conditions was observed. Single factor may not be sufficient to detail the difference in glucose production, and several factors affected the hydrolysis efficiency of the residues. Overall, the MTHF/H2O system effectively converted cornstalk into furfural and glucose via a simple and environment-friendly process, thus was an ideal manner for the food industries.

Microencapsulation and Nanoencapsulation: A Review

2017 ◽  
Vol 9 (3) ◽  
Author(s):  
V. Suganya ◽  
V. Anuradha
Keyword(s):  
Drug Release ◽  
New Technology ◽  
Inert Material ◽  
Food Industries ◽  
Control Drug ◽  
Advantages And Disadvantages ◽  
Nano Scale ◽  
Pharmaceutical Industries ◽  
The Difference ◽  
Control Drug Release

Encapsulation is a process of enclosing the substances within an inert material which protects from environment as well as control drug release. Recently, two type of encapsulation has been performed in several research. Nanoencapsulation is the coating of various substances within another material at sizes on the nano scale. Microencapsulation is similar to nanoencapsulation aside from it involving larger particles and having been done for a greater period of time than nanoencapsulation. Encapsulation is a new technology that has wide applications in pharmaceutical industries, agrochemical, food industries and cosmetics. In this review, the difference between micro and nano encapsulation has been explained. This article gives an overview of different methods and reason for encapsulation. The advantages and disadvantages of micro and nano encapsulation technology were also clearly mentioned in this paper.

scholarly journals The Role of Internal Control in Firms’ Coping with the Impact of the COVID-19 Pandemic: Evidence from China

2021 ◽  
Vol 13 (11) ◽  
pp. 6294
Author(s):  
Peiqing Zhu ◽  
Jianbo Song
Keyword(s):  
Internal Control ◽  
Manufacturing Industry ◽  
Firm Heterogeneity ◽  
Negative Impact ◽  
Risk Prevention ◽  
High Tech ◽  
Obvious Effect ◽  
The Difference ◽  
The Impact

Internal control plays a role in risk prevention for firms when dealing with serious emergencies, which ensures the sustainable development of firms during a crisis. Based on the rapid outbreak of COVID-19 in China, this paper empirically tests whether internal control alleviates the negative impact of the pandemic on firm performance. Using a sample of Chinese listed firms from the first quarter of 2019 to the third quarter of 2020 and employing the difference-in-difference (DID) method, we find that the firms with a higher quality of internal control achieve better financial performance during the pandemic period; the more serious the pandemic is, the more obvious effect internal control plays. Furthermore, we consider the industry heterogeneity and firm heterogeneity of the risk resistance effect of internal control. In the manufacturing industry, which is a “disaster zone” of the pandemic, and the non-high-tech industry with a low degree of digitization, internal control can play a more important role in firms’ performance. Moreover, for state-owned enterprises, and firms with strong financing constraints, the role of internal control is more prominent. The above results provide empirical evidence for the risk prevention function of internal control and shed new light on the measures for firms to resist emergencies in the future.

Effects of acute exercise on the gluconeogenic capacity of periportal and perivenous hepatocytes

2001 ◽  
Vol 91 (3) ◽  
pp. 1099-1104 ◽  
Author(s):  
François Désy ◽  
Yan Burelle ◽  
Patrice Bélanger ◽  
Marielle Gascon-Barré ◽  
Jean-Marc Lavoie
Keyword(s):  
Incubation Medium ◽  
Acute Exercise ◽  
Metabolic Response ◽  
Liver Perfusion ◽  
Glucose Production ◽  
Selective Destruction ◽  
Single Bout ◽  
Lactate And Pyruvate ◽  
The Difference ◽  
Exercise Induced

The present study was conducted to examine the effect of a single bout of exercise (rodent treadmill, 60 min at 26 m/min, 0% grade) on the gluconeogenic activity of periportal hepatocytes (PP-H) and perivenous hepatocytes (PV-H) in fasted (18 h) rats. Isolated PP-H and PV-H, obtained by selective destruction following liver perfusion with digitonin and collagenase, were incubated with saturating concentrations of alanine (Ala; 20 mM) or a mixture of lactate and pyruvate (Lac+Pyr; 20:2 mM) to determine the glucose production flux ( J glucose) in the incubation medium. Results show that, in the resting conditions, J glucose from all exogenous substrates was significantly higher ( P < 0.01) in PP-H than in PV-H. Exercise, compared with rest, resulted in a higher J glucose ( P < 0.01) from Lac+Pyr substrate in the PV-H but not in the PP-H, resulting in the disappearance of the difference in J glucosebetween PP-H and PV-H. Exercise, compared with rest, led to a higher J glucose ( P < 0.01) from Ala substrate in both PP-H and PV-H. However, the exercise-induced increase in J glucose (gluconeogenic activity) from Ala substrate was higher in PV-H than in PP-H, resulting, as from Lac+Pyr substrate, in the disappearance ( P > 0.05) of the difference of J glucose between PP-H and PV-H. It is concluded that exercise differentially stimulates the gluconeogenic activity of PV-H to a larger extent than PP-H, indicative of a heterogenous metabolic response of hepatocytes to exercise.

Measurement of gluconeogenesis in exercising men by mass isotopomer distribution analysis

2002 ◽  
Vol 93 (1) ◽  
pp. 233-241 ◽  
Author(s):  
Jeff K. Trimmer ◽  
Jean-Marc Schwarz ◽  
Gretchen A. Casazza ◽  
Michael A. Horning ◽  
Nestor Rodriguez ◽  
...  
Keyword(s):  
Rest Period ◽  
Glucose Production ◽  
Moderate Intensity ◽  
Dependent Manner ◽  
Distribution Analysis ◽  
Moderate Intensity Exercise ◽  
Isotopomer Distribution ◽  
Mass Isotopomer Distribution Analysis ◽  
The Difference ◽  
Mass Isotopomer

We evaluated the hypothesis that coordinated adjustments in absolute rates of gluconeogenesis (GNGab) and hepatic glycogenolysis (Gly) would maintain euglycemia and match glucose production (GP) to peripheral utilization during rest and exercise. Specifically, we evaluated the extent to which gradations in exercise power output would affect the contribution of GNGab to GP. For these purposes, we employed mass isotopomer distribution analysis (MIDA) and isotope-dilution techniques on eight postabsorptive (PA) endurance-trained men during 90 min of leg cycle ergometry at 45 and 65% peak O2 consumption (V˙o 2 peak; moderate and hard intensities, respectively) and the preceding rest period. GP was constant in resting subjects, whereas the fraction from GNG (fGNG) increased over time during rest (22.3 ± 0.9% at 11.25 h PA vs. 25.6 ± 0.9% at 12.0 h PA, P < 0.05). In the transition from rest to exercise, GP increased in an intensity-dependent manner (rest, 2.0 ± 0.1; 45%, 4.0 ± 0.4; 65%, 5.84 ± 0.64 mg · kg−1 · min−1, P < 0.05), although glucose rate of disappearance exceeded rate of appearance during the last 30 min of exercise at 65%V˙o 2 peak. Compared with rest, increases in GP were sustained by 92 and 135% increments in GNGab during moderate- and hard-intensity exercises, respectively. Correspondingly, Gly (calculated as the difference between GP and MIDA-measured GNGab) increased 100 and 203% over rest during the two exercise intensities. During moderate-intensity exercise, fGNG was the same as at rest; however, during the harder exercise fGNG decreased significantly to account for only 21% of GP. The highest sustained GNGab observed in these trials on PA men was 1.24 ± 0.3 mg · kg−1 · min−1. We conclude that, after an overnight fast, 1) absolute GNG rates increased with intensity of effort despite a reduced fGNG at 65% V˙o 2 peak, 2) during exercise Gly is more responsible than GNGab for maintaining GP, and 3) in 12-h fasted men, neither increased Gly or GNGab nor was their combination able to maintain euglycemia during prolonged hard (65%V˙o 2 peak) exercise.

Optimization of Furfural Production from Xylose by RSM Using Chromium Sulfate as Catalyst

2014 ◽  
Vol 881-883 ◽  
pp. 29-34
Author(s):  
Ye Zhang ◽  
Ming Qiang Chen ◽  
Jun Wang
Keyword(s):  
Strong Influence ◽  
Catalyst Loading ◽  
Response Analysis ◽  
Solid Residue ◽  
Independent Variables ◽  
Temperature Time ◽  
Surface Response Analysis ◽  
Central Composite ◽  
Chromium Sulfate ◽  
Furfural Production

Optimization of chromium sulfate catalyzed conversion conditions of xylose into furfural was studied by response surfacemethodology (RSM). A central composite design (CCD) was used to determine the effects of independent variables, including temperature (120-160°C), time (30-150min), catalyst loading (1-5mmol) and moles of xylose (2.5-12.5mmol) on furfural yield, xylose conversion and solid residue. The surface response analysis revealed that temperature, time, catalyst loading and moles of xylose had a strong influence on the furfural yield, whereas moles of xylose was found to be notsignificant for xylose conversion. The solid residue was affected by temperature, time and moles of xylose. The maximumpredicted furfural yield was 45.07% at temperature of 150°C, time of 12min, catalyst loading of 2 mmol and moles of xylose of 10mmol. Under this condition, xylose conversion could be reached 100%.

scholarly journals Furfural production in a biphasic system using a carbonaceous solid acid catalyst

2019 ◽  
Vol 585 ◽  
pp. 117180 ◽  
Author(s):  
Gerardo Gómez Millán ◽  
Josphat Phiri ◽  
Mikko Mäkelä ◽  
Thad Maloney ◽  
Alina M. Balu ◽  
...  
Keyword(s):  
Solid Acid ◽  
Solid Acid Catalyst ◽  
Acid Catalyst ◽  
Biphasic System ◽  
Furfural Production

scholarly journals Glucagon sensitivity and clearance in type 1 diabetes: insights from in vivo and in silico experiments

2015 ◽  
Vol 309 (5) ◽  
pp. E474-E486 ◽  
Author(s):  
Ling Hinshaw ◽  
Ashwini Mallad ◽  
Chiara Dalla Man ◽  
Rita Basu ◽  
Claudio Cobelli ◽  
...  
Keyword(s):  
Type 1 Diabetes ◽  
In Silico ◽  
Artificial Pancreas ◽  
Glucose Production ◽  
Endogenous Glucose Production ◽  
Action Model ◽  
The Difference ◽  
Hormone Control

Glucagon use in artificial pancreas for type 1 diabetes (T1D) is being explored for prevention and rescue from hypoglycemia. However, the relationship between glucagon stimulation of endogenous glucose production (EGP) viz., hepatic glucagon sensitivity, and prevailing glucose concentrations has not been examined. To test the hypothesis that glucagon sensitivity is increased at hypoglycemia vs. euglycemia, we studied 29 subjects with T1D randomized to a hypoglycemia or euglycemia clamp. Each subject was studied at three glucagon doses at euglycemia or hypoglycemia, with EGP measured by isotope dilution technique. The peak EGP increments and the integrated EGP response increased with increasing glucagon dose during euglycemia and hypoglycemia. However, the difference in dose response based on glycemia was not significant despite higher catecholamine concentrations in the hypoglycemia group. Knowledge of glucagon's effects on EGP was used to develop an in silico glucagon action model. The model-derived output fitted the obtained data at both euglycemia and hypoglycemia for all glucagon doses tested. Glucagon clearance did not differ between glucagon doses studied in both groups. Therefore, the glucagon controller of a dual hormone control system may not need to adjust glucagon sensitivity, and hence glucagon dosing, based on glucose concentrations during euglycemia and hypoglycemia.

Renal gluconeogenesis: axial and internephron heterogeneity and the effect of parathyroid hormone

1984 ◽  
Vol 246 (1) ◽  
pp. F59-F66 ◽  
Author(s):  
M. S. Wang ◽  
K. Kurokawa
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Ions ◽  
Glucose Production ◽  
Cellular Responses ◽  
Nephron Segments ◽  
Renal Gluconeogenesis ◽  
The Difference ◽  
Proximal Tubule Segments ◽  
Camp Formation ◽  
Gluconeogenic Substrate

To better understand the regulation of renal gluconeogenesis that occurs in the proximal nephron, glucose production rates from various substrates were determined in defined proximal tubule segments of the rat. Tubule segments tested were the S1 and S2 segments of superficial (SF) nephrons, the S1 segments of juxtamedullary (JM) nephrons, and the S3 segments. Glucose production (in decreasing order) was: from alpha-ketoglutarate, JM S1, SF S1, SF S2; from pyruvate, SF S2, JM S1, and SF S1; from glutamine, SF S1, JM S1; and from glutamate, SF S1 = JM S1. Little glucose was produced in the S3 segments. Glucose production from glutamate was lower than that from the other three substrates in JM S1, and glutamine was the best gluconeogenic substrate in SF S1. The effects of parathyroid hormone (PTH), a known stimulator of renal gluconeogenesis, and cAMP were examined using alpha-ketoglutarate as the substrate. Both stimulated glucose production in the S1 and S2 segments of the SF nephron. Although PTH stimulated adenylate cyclase in the S1 segments of the SF and JM nephrons, it had no effect on glucose production in the JM S1. Glucose production rose in the SF S1 and JM S1 in response to increasing concentrations of hydrogen or calcium ions, indicating that gluconeogenesis can be increased in these nephron segments. Differences may therefore be present in the cellular responses to PTH distal to cAMP formation in the nephron segments of the SF and JM nephrons. These findings show the presence of both axial and internephron heterogeneity of renal gluconeogenesis and suggest the difference in the effects of PTH on the function of SF and JM nephrons.

A Correlation for Nusselt Number Under Turbulent Mixed Convection Using Transient Heat Transfer Experiments

2010 ◽  
Author(s):  
N. Gnanasekaran ◽  
C. Balaji
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Mixed Convection ◽  
A Priori ◽  
Convective Heat Transfer Coefficient ◽  
Time History ◽  
Vertical Channel ◽  
The Difference ◽  
Nusselt Number Correlation ◽  
Temperature Time

This paper reports the results of an experimental investigation of transient, turbulent mixed convection in a vertical channel in which one of the walls is heated and the other is adiabatic. The goal is to simultaneously estimate the constants in a Nusselt number correlation whose form is assumed a priori by synergistically marrying the experimental results with repeated numerical calculations that assume guess values of the constants. The convective heat transfer coefficient “h” is replaced by the Nusselt number (Nu) which is then assumed to have a form Nu = a (1+RiD) b ReDc where a, b and c are the constants to be evaluated. From the experimentally obtained temperature time history and the simulated temperature time history, based on some guess values of a, b, and c, one can define the objective function or the residue as the sum of the square of the difference between experimentally obtained and simulated temperatures. Using Bayesian inference driven by the Markov chain Monte Carlo method, one, more or all of the constants a, b and c are retrieved together with the uncertainty involved in these estimates. Additionally, the estimated parameters are compared with experimental benchmarks.

Sign in / Sign up

Export Citation Format

Share Document