Decrease In Total Surface Area Research Articles

The relationship between coffee-related factors and cortical and hippocampal structure: a triangulation of evidence approach and Mendelian randomization research.

Existing studies have reported sustained changes in the cortical structure of rats due to coffee-related factors, which are speculated to occur in the human body. However, there is a lack of research on this topic. Additionally, previous observational studies have found the impact of diseases on cortical structure and the potential therapeutic effects of coffee on these diseases. Our aim was to study the causal effects of coffee-related factors on the human brain using SNPs (single nucleotide polymorphisms). We will connect these discovered causal effects to the impact of diseases on the brain. Through triangulating evidence, we will reveal the potential active areas of coffee in preventing diseases. We utilized GWAS data from multiple cohorts and their databases, selecting instrumental variables for genetic prediction of coffee intake and plasma levels of caffeine and its direct metabolites. We applied these instrumental variables to individual data on cortical thickness and surface area, as well as hippocampal volume, from the ENIGMA and CHARGE consortium for Mendelian randomization analysis (MR). Triangular evidence was obtained by integrating existing evidence through a specified retrieval strategy, calculating the overlap between coffee's effects on brain regions and disease-related brain regions to identify potential regions of action. The MR analysis yielded 93 positive results for 9 exposures, among which theobromine, a metabolite in the caffeine pathway, was found to be associated with increased hippocampal volume. For cortical structure, theobromine in the caffeine pathway was associated with a decrease in total surface area, while theobromine and caffeine in the pathway were associated with an increase in total thickness. The overlap rate of triangular evidence showed no difference in both overall and subgroup analyses, indicating a high overlap between the effects of coffee on brain regions and disease. From predicted outcomes from causal effects, coffee intake-related factors may have lasting effects on cortical structure. Additionally, theobromine and theophylline have the greatest impact on certain brain gyri, rather than caffeine. Triangulation evidence indicates that disease and coffee intake-related factors act on the same cortical regions, suggesting the presence of potential shared or antagonistic pathways.

Anisotropic microstructural evolution and coarsening in free sintering and constrained sintering of metal film by using FIB-SEM tomography

The anisotropic microstructure develops during powder processing and constrained sintering. FIB-SEM tomography was used to investigate the microstructural evolutions of Au submicron particles during free sintering and constrained sintering. The decrease in total surface area and the coarsening, i.e. the increase of mean intercept length of solid phase, were observed during the densification process. The anisotropic packing structure of spherical particles induced by casting process was characterized by area weighted fabric tensor, which represented the bond orientation and the anisotropy of contact area. In free sintering, the initial anisotropy in packing structure decreased with densification. In constrained sintering, the initial anisotropy observed by the mean intercept length of pore was reversed in the later stage. The microstructure evolved so as to form the elongated pores along the thickness direction. An open pore structure model was presented to explain the microstructural evolution in the intermediate stage.

Electrostatic Self-Assembly Approach to Fabricate Architectures of Carboxyl Functionalized Gold-Aryl Nanoparticles and Graphene Oxide Platforms

Graphene oxide (GO) was decorated with gold-aryl (Au-C) nanoparticles AuNPs-COOH by sodium borohydride reduction of aryldiazonium tetrachloroaurate(III) salt at room temperature in aqueous solutions. Brunauer-Emmett-Teller measurements supported GO anchoring by AuNPs modified with COOH; surface area dropped significantly. Morphology of AuNPs-COOH/GO nanocomposite (NC) was probed using AFM and TEM, showing NC’s surface roughness and wrinkling. XPS results suggest the clear reductive reaction of tetrachloroaurate anion into metallic gold in AuNPs-COOH/GO along with detailed interpretations of functional groups’ nature. Molecular dynamics calculations endowed support of favorable wrinkling at the edges and carboxyl intercalation to GO surface of types π- π, hydrogen bonding, and hydrophobic interactions. Solvent accessible surface area calculations of GO showed a decrease in total surface area. Environmental nanoremediation of the catalytic reduction of 4-nitrophenol, a priority pollutant listed by USEPA, was investigated. The apparent rate constants Kapp of four catalytic reduction cycles of nitrophenol were measured. The highest value is 1.17 × 10-1 min-1 for the first cycle which decreased to 4.49 × 10 -2 min -1 for the fourth cycle. The variations in rate constants were measured with different conditions, including NaBH 4 concentrations, NC loadings and NC incubating time in NaBH4.

Anisotropic Microstructural Evolution and Coarsening in Free Sintering and Constrained Sintering of Metal Film by Using FIB-SEM Tomography

The anisotropic microstructure develops during powder processing and constrained sintering. In the present study, the microstructural evolutions of Au submicron particles during free sintering and constrained sintering were investigated by FIB-SEM tomography. The decrease in total surface area and the coarsening, i.e. the increase of mean intercept length of solid phase, were observed during the densification process. The anisotropic packing structure of spherical particles induced by casting process was characterized by area weighted fabric tensor, which represented the bond orientation and the anisotropy in contact area. In free sintering, the initial anisotropy in packing structure decreased with densification as indicated by the decrease in deviatoric component of surface energy tensor. In constrained sintering, the initial anisotropy observed by the mean intercept length of pore was reversed in the later stage. The microstructure evolved so as to form the elongated pores along the thickness direction.

RNASeq analysis reveals upregulation of complement C3 in the offspring gut following prenatal stress in mice

Dysregulated activation of inflammatory signaling by the immature neonatal immune system could lead to the development of many pediatric diseases including necrotizing enterocolitis (NEC). While the mechanism(s) of pathogenesis is unknown, NEC is believed to have multifactorial causes. Microbial dysbiosis and intestinal immaturity have been implicated as potential triggers for this disease. We hypothesized that psychological stress during pregnancy negatively impacts the development of intestinal tissues in offspring and contributes to development of NEC. Consistent with this hypothesis, we previously observed shorter villi and a decrease in total surface area in the small intestine of pups derived from mice that were chronically stressed during gestation. In this study, we performed RNASeq analysis to determine the gene expression changes in the offspring gut following prenatal stress in pregnant mice and identified several differentially expressed genes (DEGs) and biological pathways. Notably, C3 was upregulated in the small intestine and contributed to a higher tissue injury score in a mesenteric ischemia model compared to unstressed controls. We discuss the potential implications of these stress-induced genes expression changes and their contribution to development of intestinal inflammation.

Catalytic upgrading of lignite pyrolysis volatiles over modified HY zeolites

HY zeolite is modified by hydrothermal and HNO3 treatment and used as the catalyst to upgrade Baiyinghua pyrolysis volatiles on a fixed-bed reactor at 600 °C. The results show that hydrothermal and acid treatment obviously affect zeolite structure and upgrading of pyrolysis volatiles. The dealumination of HY increases with hydrothermal temperature, resulting in the decrease of total surface area and acid amount and the formation of larger pores. However, the content and yield of light tar are enhanced over modified HY, and the cracking of volatiles into gas is retarded. Acid treatment of hydrothermal modified HY at 650 °C removes extra-framework Al, improves surface area and the volatiles cracking. But high acid concentration leads to the destruction of zeolite structure, and is unfavorable to the upgrading. Modified HY by treatment at 650 °C and 0.8 mol/L HNO3 shows the best performance in catalytic volatiles upgrading. About 81.5 wt% light tar content and 61.1% light aromatic hydrocarbons content can be obtained. Especially, the yields of naphthalene and methylnaphthalene are increased by 8.9 and 6.8 times. The content of oxygenated PAHs is reduced by 4.3 times. The improved performance is mainly due to high surface area, large pore diameter and suitable acidity.

Investigation of faceted void morphologies in UO2 by phase field modelling

In the present study a phase field model for high surface energy anisotropy is developed to model the morphologies of voids in UO2. In order to precisely account for the high anisotropy, an alternative forward-backward strategy based on a staggered grid with an averaged interface normal scheme is used in the numerical procedure. A variety of equilibrium void shapes are reproduced with respect to a constant volume condition. The facet areas and facet energies are calculated. The simulations show excellent agreement with the analytic predictions obtained through Wulff constructions. For the void shapes with high Miller index facets, it is discovered that a slight decrease in total surface area will result in a substantial increase in the total surface energy.

Fixed-bed column sorption of borate onto pomegranate seed powder-PVA beads: a response surface methodology approach

Pomegranate seed powder (PS) was functionalized with polyvinyl alcohol (PVA) and utilized for boron removal from the aqueous system. Results of Brunauer--Emmett--Teller (BET) surface area analysis and Boehm titration indicated notable decrease in total surface area and increase in acidic surface functional groups of PS after PVA modification. Enhanced sorption is indicative of complex formation between diol groups of the pomegranate seed powder--polyvinyl alcohol (PS–PVA) and borate ions. Under column test, the saturated sorption capacity of boron was noted to be dependent on flow rate and bed height. The developed central composite design (CCD) was adequate to elucidate the sorption mechanism. Mathematical modeling of the column data was conducted, and a modified-dose-response model was the most suitable to describe the breakthrough curve and observed to be consistent with CCD analysis. This is further supported by extensive error analyses conducted between the model predicted and experimental data.

Laser-perforated carbon paper electrodes for improved mass-transport in high power density vanadium redox flow batteries

In this study, we demonstrate up to 30% increase in power density of carbon paper electrodes for vanadium redox flow batteries (VRFB) by introducing perforations into the structure of electrodes. A CO2 laser was used to generate holes ranging from 171 to 421 μm diameter, and hole densities from 96.8 to 649.8 holes cm−2. Perforation of the carbon paper electrodes was observed to improve cell performance in the activation region due to thermal treatment of the area around the perforations. Results also demonstrate improved mass transport, resulting in enhanced peak power and limiting current density. However, excessive perforation of the electrode yielded a decrease in performance due to reduced available surface area. A 30% increase in peak power density (478 mW cm−2) was observed for the laser perforated electrode with 234 μm diameter holes and 352.8 holes cm−2 (1764 holes per 5 cm2 electrode), despite a 15% decrease in total surface area compared to the raw un-perforated electrode. Additionally, the effect of perforation on VRFB performance was studied at different flow rates (up to 120 mL min−1) for the optimized electrode architecture. A maximum power density of 543 mW cm−2 was achieved at 120 mL min−1.

Effect of Different Calcination Duration on Physicochemical Properties of Vanadium Phosphate Catalysts

Vanadium phosphate catalysts have been prepared by calcining VOHPO44·0.5H2O which were prepared via two methods i.e. organic (VPO method) and dihydrate (VPD method) routes for different duration under anaerobic atmosphere. Increasing the calcinations duration led to a decrease in total surface area. It is also promote the formation of V5+phase in the catalysts. Scanning electron microscopy clearly revealed that the morphologies of all catalysts composed of plate-like crystallites that were arranged into the characteristic of rosette cluster. However, by increasing the pretreatment duration in an inert environment, the rosette-shape of the clusters which normally obtained in reaction condition was collapsed. Prolong the duration of N2calcination also resulted in an increment in the amount of oxygen desorbed (from O2-TPD) and removed (obtained from H2-TPR).

The effect of Fe/Cu ratio in the synthesis of mixed Fe,Cu,Al-clays used as catalysts in phenol peroxide oxidation

Mixed Fe,Cu,Al-clays (Fe,Cu,Al-MM) were prepared from Ca-montmorillonite (Mukhortala, Buryatia) at OH/(Fe+Cu+Al) 2.4 and Al/(Fe+Cu) 10/1. Effect of Fe/Cu ratio of Fe,Cu,Al-containing pillaring solution on structural properties of Fe,Cu,Al-MM was examined. Characterization studies were performed by use of XRD, FTIR, DR-UV–vis and N2-adsorption/desorption analysis. The increase in copper loading leads to the decrease in total surface area, micropore volume and interlay distance of Fe,Cu,Al-MMs. It was found that the decrease in Fe/Cu ratio is favourable for the formation of oligomeric iron species. The relationships between preparation conditions, iron state, catalytic activity and stability to leaching were revealed in wet phenol oxidation with H2O2. The introduction of copper ions results in catalytic reaction acceleration that was interpreted in terms of the increase of radical generation rate.

Commentaries on Viewpoint: Use of mean airspace chord length to assess emphysema

to the editor: Although mean airspace chord length ( L m) lacks the elegance of some stereology methods and requires careful attention to technique ([4][1]), Mitzner ([3][2]) argues that L m has utility in studying experimental emphysema. Clearly, L m reflects the dimensions of alveoli but is not a

Synthesis of nano-sized TiO 2/poly(AA- co-MMA) composites by heterocoagulation and blending with PET

Nano-sized TiO 2 or SiO 2/TiO 2 particles were prepared by hydrolysis and condensation reactions in aqueous media, followed by mixing with poly(AA- co-MMA) latex to form different composites, then blending with poly(ethylene terephthalate), PET. The TGA results of composites indicated that negative charged latexes had greater interaction with TiO 2/ or SiO 2/TiO 2 particles through strong electrostatic forces, while cationic latexes incorporated with TiO 2 or SiO 2/TiO 2 particles by pH induced coagulation, carbonyl group chelation and hydrogen bonding. The soapless latex polymer particles showed lower ability of adsorption to TiO 2 particles due to the decrease of total surface area of these larger particles. If SiO 2/TiO 2 particles were used instead of TiO 2 particles, unexpected high adsorption result was observed. Morphology results observed by SEM showed that PET blended with positive charged composites was more homogeneous than PET blended with negative charged composites. DSC results also indicated that the T g of PET was increased, melting temperatures ( T m or T m ′ ) were increased, and the temperature range of crystallization was narrowed after blending with the composites. The presence of composites affected the mobility and packing of PET molecular chains therefore changing the thermal properties of PET.

Changes in surface heterogeneity of multi-walled carbon nanotubes due to adsorption of poly(acrylic acid) by derivative isotherm summation method

The heterogeneity of surface energy of multi-walled carbon nanotubes (MWNTs) before and after the adsorption of poly(acrylic acid) (PAA) is investigated on the basis of low-pressure adsorption isotherms of nitrogen at 77 K using derivative isotherm summation (DIS) method. Two types of dominant energetic surfaces are recognized in the pure MWNTs. While raising the adsorption amount of PAA, significant decrease in both the specific surface area and the heterogeneity of surface energy is found. It is indicated in detail that the contribution of high-energy surface reduces remarkably due to screening effect of adsorbed PAA, and PAA molecules could block some interparticle pores resulting in the decrease in total surface area of MWNTs. DIS analysis of the low-pressure data of the nitrogen adsorption isotherms was shown to be a feasible and effective tool to characterize the surface heterogeneity of nanoparticles.

Morphology of Nanostructured Films for Environmental Applications: Simulation of Simultaneous Sintering and Growth

A sequential Brownian dynamics approach was used to establish the morphological evolution of a nanostructured particle deposit accounting for random diffusion, particle–particle and particle–surface interactions through van der Waals forces, and sintering of deposited particles. Monodisperse (30nm radius) titanium dioxide particles were used in the simulations. A linear sintering law rate expression was used to account for the decrease in total surface area of the deposit. Characteristics such as packing thickness, total surface area, and fractal dimension are reported as a function of time during the deposition process. Sintering resulted in higher fractal dimensions (as defined) for the deposits, and elevated temperatures resulted in more compact deposits.

Morphometric Analysis of Rat Hepatocytes After Total Biliary Obstruction

Using light and electron microscopic morphometric techniques, the effects of 48 hr of extrahepatic biliary obstruction on hepatocyte structure were examined in the rat. Liver cells near the portal area were compared to those in the centrilobular regions of the hepatic lobule. Observations on the normal animals confirm earlier evidence of quantitative differences in the surface density of organelles in hepatocytes located within different regions of the lobule. A striking difference in the quantity of the Golgi complex in the two areas of the lobule was noted for the first time, with the portal cells containing a significantly greater quantity of this organelle than centrolobular hepatocytes. After 48 hr of total obstruction, most of the previously reported qualitative changes in the canalicular and pericanalicular regions were confirmed. Morphometric analysis at the light-microscopic level showed an increase in the number of cells and a decrease in cell size in those cells near the portal area were compared to those in the centrolobular regions of the helar level demonstrated a significant decrease in both rough and smooth surfaced endoplasmic reticulum in cells of both zones, a finding in marked contrast to the hypertrophy of smooth endoplasmic reticulum suggested by other investigators on the basis of qualitative assessments. There was also a striking decrease in the amount of the Golgi complex, limited to cells in the portal regions. In addition, in all zones a decrease in the volume density of mitochondria and lysosomes was noted, whereas the volume of microbodies was increased. It is suggested that this loss in total membrane material within the cell may be secondary to the degranulation and decrease in total surface area of rough surfaced endoplasmic reticulum, an organelle thought to be responsible in part for the synthesis of new cellular membranes. These observations suggest that present concepts concerning the pathogenesis of cholestatic liver disease require reappraisal.