scholarly journals Dietary fructose v. glucose in rats raises urinary excretion, true absorption and ileal solubility of magnesium but decreases magnesium retention

1994 ◽  
Vol 72 (4) ◽  
pp. 567-577 ◽  
Author(s):  
Annet Van Der Heijden ◽  
Gerrit J. Van Den Berg ◽  
Arnoldlna G. Lemmens ◽  
Anton C. Beynen
Keyword(s):  
Liquid Phase ◽  
Urinary Excretion ◽  
Solid Phase ◽  
Intraperitoneal Administration ◽  
Faecal Excretion ◽  
Apparent Absorption ◽  
True Absorption ◽  
Liquid Phases ◽  
Dietary Fructose ◽  
Stimulation Of

Apparent Mg absorption, that is Mg intake minus faecal excretion, was found to be greater in rats fed on diets containing fructose instead of glucose. This effect of fructose was accompanied by enhanced urinary excretion and diminished retention of Mg. True Mg absorption was then determined with the use of oral and intraperitoneal administration of tracer doses of 28Mg. True Mg absorption was significantly greater in rats fed on fructose. There was no significant effect of fructose v. glucose on faecal excretion of endogenous Mg. It was hypothesized that fructose enhances the solubility of Mg in the ileal lumen and thereby facilitates its absorption. The distribution of Mg between the solid and liquid phases of the ileum was determined in rats fed on either glucose or fructose. Fructose reduced the amount of Mg in the solid phase but raised both the amount and the concentration of Mg in the liquid phase. We conclude that the dietary-fructose-induced stimulation of Mg absorption in rats is caused by a raised solubility of ileal Mg. but the mechanism by which fructose exerts this effect and why it was not associated with a decrease in faecal excretion of endogenous Mg remain unknown. Dietary fructose v. glucose did not systematically affect the apparent absorption of Ca and P.

Multiphase Reactions and Reactors

2001 ◽  
Author(s):  
L. K. Doraiswamy
Keyword(s):  
Liquid Phase ◽  
Solid Phase ◽  
Complete Classification ◽  
Catalytic Reactions ◽  
Two Phase ◽  
Multiphase Reactions ◽  
Liquid Phases ◽  
Three Phase ◽  
Solid Form

The first three chapters of this part dealt with two-phase reactions. Although catalysts are not generally present in these systems, they can be used in dissolved form in the liquid phase. This, however, does not increase the number of phases. On the other hand, there are innumerable instances of gas-liquid reactions in which the catalyst is present in solid form. A popular example of this is the slurry reactor so extensively employed in reactions such as hydrogenation and oxidation. There are also situations where the solid is a reactant or where a phasetransfer catalyst is immobilized on a solid support that gives rise to a third phase. A broad classification of three-phase reactions and reactors is presented in Table 17.1 (not all of which are considered here). This is not a complete classification, but it includes most of the important (and potentially important) types of reactions and reactors. The thrust of this chapter is on reactions and reactors involving a gas phase, a liquid phase, and a solid phase which can be either a catalyst (but not a phasetransfer catalyst) or a reactant, with greater emphasis on the former. The book by Ramachandran and Chaudhari (1983) on three-phase catalytic reactions is particularly valuable. Other books and reviews include those of Shah (1979), Chaudhari and Ramachandran (1980), Villermaux (1981), Shah et al. (1982), Hofmann (1983), Crine and L’Homme (1983), Doraiswamy and Sharma (1984), Tarmy et al. (1984), Shah and Deckwer (1985), Chaudhari and Shah (1986), Kohler (1986), Chaudhari et al. (1986), Hanika and Stanek (1986), Joshi et al. (1988), Concordia (1990), Mills et al. (1992), Beenackers and Van Swaaij (1993), and Mills and Chaudhari (1997). Doraiswamy and Sharma (1984) also present a discussion of gas-liquid-solid noncatalytic reactions in which the solid is a reactant. In Chapter 7 we saw how Langmuir-Hinshelwood-Hougen-Watson (LHHW) models are normally used to describe the kinetics of gas-solid (catalytic) or liquid-solid (catalytic) reactions, and in Chapters 14 to 16 we saw how mass transfer between gas and liquid phases can significantly alter the rates and regimes of these two-phase reactions.

scholarly journals Digesta transit in different segments of the gastrointestinal tract of pigs as affected by insoluble fibre supplied by wheat bran

2007 ◽  
Vol 98 (1) ◽  
pp. 54-62 ◽  
Author(s):  
Aurélie Wilfart ◽  
Lucile Montagne ◽  
Howard Simmins ◽  
Jean Noblet ◽  
Jaap van Milgen
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Liquid Phase ◽  
Large Intestine ◽  
Dietary Fibre ◽  
Solid Phase ◽  
Latin Square ◽  
Fibre Content ◽  
Liquid Phases ◽  
Insoluble Fibre

Digestibility is the result of two competing processes: digestion and digesta transit. To develop or parameterise mechanistic models of digestion, both processes have to be quantified. The aim of this study was to determine the effect of insoluble dietary fibre on the transit in the gastrointestinal tract of pigs. Six barrows (33 kg initial body weight and fitted with two simple T-cannulas at the proximal duodenum and distal ileum) were used in a double 3 × 3 Latin square design. Pigs were offered diets differing in total dietary fibre content (170, 220 and 270 g/kg DM) at 4 h intervals. A single meal marked with YbO2and Cr-EDTA was used to determine the kinetics of markers concentrations of the solid and liquid phases, respectively. The mean retention time (MRT), calculated by the method of the moments, averaged 1, 4 and 38 h in the stomach, small intestine and large intestine, respectively. Increasing the insoluble fibre content in the diet had no effect on MRT in the stomach and decreased the MRT of both phases in the small intestine (P < 0·05). In the large intestine, increasing the insoluble fibre content decreased the MRT of the liquid phase (P = 0·02) and tended to decrease the MRT of the solid phase (P = 0·06). Transit of the solid phase in the large intestine was 4–8 h slower than transit of the liquid phase. Analysis of marker excretion curves indicated that the small and large intestine should be represented mathematically to have both a tubular (propulsion) and compartmental (mixing) structure.

scholarly journals Comparison of the Molecular Dynamics of C70 in the Solid and Liquid Phases

2009 ◽  
Vol 2009 ◽  
pp. 1-7 ◽  
Author(s):  
R. M. Hughes ◽  
P. Mutzenhardt ◽  
A. A. Rodriguez
Keyword(s):  
Molecular Dynamics ◽  
Solid State ◽  
Liquid Phase ◽  
Lower Energy ◽  
Solid Phase ◽  
Small Step ◽  
Correlation Times ◽  
Diffusion Constants ◽  
Liquid Phases ◽  
Two Phases

A previous study of C70 in deuterated benzenes generated evidence suggesting C70 exhibited unique reorientational behavior depending on its environment. We present a comparison of the dynamic behavior of this fullerene, in the solid and solution phases, to explore any unique features between these two phases. The effective correlation times, τCeff, of C70 in the solid state are 2 to 3 times longer than in solution. In the solid state, a noticeable decrease in all the carbons' correlation times is seen between 293 K to 303 K; suggesting a transition from isotropic to anisotropic reorientational behavior at this temperature change. Although C70 in solution experiences van der Waals type interactions, these interactions are not strong enough to slow the solution-state motion below what is observed in the solid state. All observed differences in the diffusion constants, DX and DZ, in solution are smaller than in the solid state suggesting a lower energy of activation between these two modes of reorientation in the liquid phase. A small-step diffusion “like” condition appears to be thermally generated in the solid phase at 323 K.

Determination of perfluorinated compounds (PFCs) in solid and liquid phase river water samples in Chao Phraya River, Thailand

2011 ◽  
Vol 64 (3) ◽  
pp. 684-692 ◽  
Author(s):  
Chinagarn Kunacheva ◽  
Shuhei Tanaka ◽  
Shigeo Fujii ◽  
Suwanna Kitpati Boontanon ◽  
Chanatip Musirat ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Suspended Solids ◽  
Solid Phase ◽  
Industrial Applications ◽  
Perfluorinated Compounds ◽  
River Water Samples ◽  
Liquid Phases ◽  
Chao Phraya River ◽  
Solid Liquid

Perfluorinated compounds (PFCs), especially perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are fully fluorinated organic compounds, which have been used in many industrial applications. These chemicals have contaminated surface water all over the world even in developing countries like Thailand. The previous study showed the contamination in Chao Phraya River in 2006 and 2007. The purposes of this field study were to determine the solid and liquid phase of PFCs contamination in Chao Phraya River and to compare the changes of PFC concentration in 2008. Surveys were conducted in the lower reach of Chao Phraya River in the industrialized area. A solid phase extraction (SPE) coupled with HPLC-ESI-MS/MS were used for the analysis for ten PFCs. Ten PFCs were analyzed to identify the contamination in both solid and liquid phases. PFCs were detected in both the solid and liquid phase in every sample. PFOA was the most dominant PFC while PFPA and PFOS were also highly detected in most samples. The average loadings of PFPA, PFOA and PFOS in Chao Phraya River were 94.3, 284.6 and 93.4 g/d, respectively. PFOS concentrations did not show differences between 2006 and 2008. However, PFOA concentrations were higher in 2008/5/26, while comparing other samplings. The ratio of solid : liquid PFPA (2.1 : 1.0) [(ng/g)/(ng/L)] was lower than PFOA (13.9 : 1.0) [(ng/g)/(ng/L)] and PFOS (17.6 : 1.0) [(ng/g)/(ng/L)]. The shorter chain (more hydrophilic) PFC was better to dissolve in water rather than adsorb onto suspended solids. PFOS also showed more potential to attach in the suspended solids than PFOA.

Fixed Grid Simulation of Radiation-Conduction Dominated Solidification Process

2009 ◽  
Vol 132 (2) ◽  
Author(s):  
Piotr Łapka ◽  
Piotr Furmański
Keyword(s):  
Liquid Phase ◽  
Thermal Radiation ◽  
Solid Phase ◽  
Solidification Process ◽  
Numerical Approach ◽  
Immersed Boundary ◽  
Fixed Grid ◽  
Semitransparent Materials ◽  
Liquid Phases ◽  
Solidification Processes

In this paper conduction-radiation controlled solidification process of semitransparent materials was numerically analyzed. New approach in this kind of simulations, which is based on the fixed grid front tracking method combined with the immersed boundary technique, was adopted and examined. The presented method enables accurate dealing with solidification processes of semitransparent materials which have different optical and thermophysical properties of solid and liquid phases as well as with absorption, emission, and reflection of the thermal radiation at the solid-liquid interface without applying moving mesh methods. The proposed numerical approach was examined by solving several simplified thermal radiation problems with complex fixed and moving boundaries both in two-dimensional and axisymmetric spaces. For some of them the accuracy of obtained results was proved by comparing with reference works, other showed capabilities of the proposed method. For simplified solidification processes of semitransparent materials three configurations of optical properties, i.e., semitransparent solid phase and opaque liquid phase, opaque solid phase and semitransparent liquid phase, and semitransparent both phases were considered. The interface between solid and liquid phases was treated to be opaque, absorbing, emitting, and reflecting diffusely the thermal radiation. Results of the numerical simulations show that the presented numerical approach works well in this kind of problems and is promising for simulation of real solidification processes of semitransparent materials.

Identification of hepatitis a virus in cell cultures by solid phase immune electron microscopy

1986 ◽  
Vol 44 ◽  
pp. 238-239
Author(s):  
C.D. Humphrey ◽  
T.L. Cromeans ◽  
E.H. Cook ◽  
D.W. Bradley
Keyword(s):  
Electron Microscopy ◽  
Liquid Phase ◽  
Cell Cultures ◽  
Rapid Detection ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Solid Phase ◽  
Immune Electron Microscopy ◽  
Detection And Identification

There is a variety of methods available for the rapid detection and identification of viruses by electron microscopy as described in several reviews. The predominant techniques are classified as direct electron microscopy (DEM), immune electron microscopy (IEM), liquid phase immune electron microscopy (LPIEM) and solid phase immune electron microscopy (SPIEM). Each technique has inherent strengths and weaknesses. However, in recent years, the most progress for identifying viruses has been realized by the utilization of SPIEM.

SYNTHESIS OF HYDROGEN IN ACOUSTOPLASMA DISCHARGE IN A LIQUID-PHASE STREAM

2019 ◽  
pp. 42-48 ◽  
Author(s):  
N. A. Bulychev
Keyword(s):  
Liquid Phase ◽  
Organic Compounds ◽  
Electrode Materials ◽  
Solid Phase ◽  
Plasma Discharge ◽  
Raw Material ◽  
Two Phase ◽  
Reduced Pressure ◽  
External Power Source ◽  
Phase Medium

In this paper, the plasma discharge in a high-pressure fluid stream in order to produce gaseous hydrogen was studied. Methods and equipment have been developed for the excitation of a plasma discharge in a stream of liquid medium. The fluid flow under excessive pressure is directed to a hydrodynamic emitter located at the reactor inlet where a supersonic two-phase vapor-liquid flow under reduced pressure is formed in the liquid due to the pressure drop and decrease in the flow enthalpy. Electrodes are located in the reactor where an electric field is created using an external power source (the strength of the field exceeds the breakdown threshold of this two-phase medium) leading to theinitiation of a low-temperature glow quasi-stationary plasma discharge.A theoretical estimation of the parameters of this type of discharge has been carried out. It is shown that the lowtemperature plasma initiated under the flow conditions of a liquid-phase medium in the discharge gap between the electrodes can effectively decompose the hydrogen-containing molecules of organic compounds in a liquid with the formation of gaseous products where the content of hydrogen is more than 90%. In the process simulation, theoretical calculations of the voltage and discharge current were also made which are in good agreement with the experimental data. The reaction unit used in the experiments was of a volume of 50 ml and reaction capacity appeared to be about 1.5 liters of hydrogen per minute when using a mixture of oxygen-containing organic compounds as a raw material. During their decomposition in plasma, solid-phase products are also formed in insignificant amounts: carbon nanoparticles and oxide nanoparticles of discharge electrode materials.

Heat capacities and enthalpies of fusion and transformation for solvates of some salts with dimethyl sulfoxide and dimethylformamide

1988 ◽  
Vol 53 (12) ◽  
pp. 3072-3079
Author(s):  
Mojmír Skokánek ◽  
Ivo Sláma
Keyword(s):  
Heat Capacity ◽  
Phase Transformation ◽  
Phase Transformations ◽  
Dimethyl Sulfoxide ◽  
Liquidus Temperature ◽  
Molar Heat Capacity ◽  
Solid Phase ◽  
Zinc Nitrate ◽  
Heat Capacities ◽  
Liquid Phases

Molar heat capacities and molar enthalpies of fusion of the solvates Zn(NO3)2 . 2·24 DMSO, Zn(NO3)2 . 8·11 DMSO, Zn(NO3)2 . 6 DMSO, NaNO3 . 2·85 DMSO, and AgNO3 . DMF, where DMSO is dimethyl sulfoxide and DMF is dimethylformamide, have been determined over the temperature range 240 to 400 K. Endothermic peaks found for the zinc nitrate solvates below the liquidus temperature have been ascribed to solid phase transformations. The molar enthalpies of the solid phase transformations are close to 5 kJ mol-1 for all zinc nitrate solvates investigated. The dependence of the molar heat capacity on the temperature outside the phase transformation region can be described by a linear equation for both the solid and liquid phases.

Acetaminophen Inhibits Spinal Prostaglandin E2Release after Peripheral Noxious Stimulation 

1999 ◽  
Vol 91 (1) ◽  
pp. 231-239 ◽  
Author(s):  
Uta S. Muth-Selbach ◽  
Irmgard Tegeder ◽  
Kay Brune ◽  
Gerd Geisslinger
Keyword(s):  
Spinal Cord ◽  
Urinary Excretion ◽  
Dorsal Horn ◽  
Formalin Test ◽  
Intraperitoneal Administration ◽  
Noxious Stimulation ◽  
Cyclooxygenase Inhibitor ◽  
Nociceptive Processing ◽  
Pge2 Release

Background Prostaglandin play a pivotal role in spinal nociceptive processing. At therapeutic concentrations, acetaminophen is not a cyclooxygenase inhibitor. inhibitor. Thus, it is antinociceptive without having antiinflammatory or gastrointestinal toxic effects. This study evaluated the role of spinal prostaglandin E2 (PGE2) in antinociception produced by intraperitoneally administered acetaminophen. Methods The PGE2 concentrations in the dorsal horn of the spinal cord were measured after formalin was injected into the hind paw of rats. The effect of antinociceptive doses of acetaminophen (100, 200, and 300 mg/kg given intraperitoneally) on PGE2 levels and flinching behavior was monitored Spinal PGE2 and acetaminophen concentrations were obtained by microdialysis using a probe that was implanted transversely through the dorsal horn of the spinal cord at L4. Furthermore, the effects of acetaminophen on urinary prostaglandin excretion were determined. Results Intraperitoneal administration of acetaminophen resulted in a significant decrease in spinal PGE2 release that was associated with a significant reduction in the flinching behavior in the formalin test Acetaminophen was distributed rapidly into the spinal cord with maximum dialysate concentrations 4560 min after intraperitoneal administration. Urinary excretion of prostanoids (PGE2, PGF2alpha, and 6-keto-PGF1alpha) was not significantly altered after acetaminophen administration. Conclusions The data confirm the importance of PGE2 in spinal nociceptive processing. The results suggest that antinociception after acetaminophen administration is mediated, at least in part, by inhibition of spinal PGE2 release. The mechanism, however, remains unknown. The finding that urinary excretion of prostaglandins was not affected might explain why acetaminophen is antinociceptive but does not compromise renal safety.

scholarly journals Prion-Like Proteins in Phase Separation and Their Link to Disease

Biomolecules ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1014
Author(s):  
Macy L. Sprunger ◽  
Meredith E. Jackrel
Keyword(s):  
Protein Folding ◽  
Phase Transitions ◽  
Phase Separation ◽  
Liquid Phase ◽  
Protein Misfolding ◽  
Solid Phase ◽  
Liquid Phase Separation ◽  
Therapeutic Approaches ◽  
Important Physiological Process ◽  
Liquid Liquid Phase Separation

Aberrant protein folding underpins many neurodegenerative diseases as well as certain myopathies and cancers. Protein misfolding can be driven by the presence of distinctive prion and prion-like regions within certain proteins. These prion and prion-like regions have also been found to drive liquid-liquid phase separation. Liquid-liquid phase separation is thought to be an important physiological process, but one that is prone to malfunction. Thus, aberrant liquid-to-solid phase transitions may drive protein aggregation and fibrillization, which could give rise to pathological inclusions. Here, we review prions and prion-like proteins, their roles in phase separation and disease, as well as potential therapeutic approaches to counter aberrant phase transitions.

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