Temperature and concentration dependence of liquid phase diffusion coefficients

A study of experimental techniques for the determination of diffusion coefficients for binary mixtures and a study of the existing relationships for these coefficients were carried out. A new three-compartment diffusion cell was developed capable of measuring diffusion coefficients at temperatures up to the normal boiling point (24). By means of this cell, diffusion coefficients were measured for the systems ethanol-water, acetone-water and acetone- chloroform for a range of temperatures up to the normal boiling points. Thus diffusion coefficients for the above mixtures including those at boiling points and at infinite dilution are presented. A relationship was developed to relate diffusion coefficients with temperature and concentration (equation 3-1.21) in binary systems. It agrees better with the experimental data for the associated systems than some literature correlations. By application of parachors a new equation (3-2.4) was developed for the prediction of diffusion coefficients at infinite dilution , (201). This equation, because of the ease of calculating parachors, is more convenient to use than other equations based on the Stokes-Einstein equation. An additive method for the prediction of self-diffusion coefficients was introduced and a correlating equation (3-3.4) was developed. The bond and structural contributions to the constant of the equation were calculated on the basis of a limited amount of experimental data. Despite this the correlation gives reasonable predictions for the temperature range between melting point and boiling point. Another correlation for the prediction of self-diffusion coefficients was developed (203) (equation 3-3.6) by modifying an existing equation. This was possible by applying the relationship between the molal volume at the boiling point and the critical molal volume developed in this work (202). The new equation is more convenient to use. The correlating property of the critical temperature was used to devise a relationship between diffusion coefficients, critical temperature and the working temperature. The two correlating equations (3-4.6) and (3-4.7) can predict diffusion coefficients at various temperatures if one value of the diffusion coefficient at a single temperature is known

2-Form U(1) Spin Liquids: Classical Model and Quantum Aspects

We introduce a novel geometrically frustrated classical Ising model, dubbed the "spin vorticity model", whose ground state manifold is a novel classical spin liquid, a "2-form Coulomb phase". We study the thermodynamics of this model both analytically and numerically, exposing the presence of algebraically decaying correlations and demonstrating an extensive ground state entropy, and give a comprehensive account of its ground state properties and excitations. Each classical ground state may be decomposed into collections of closed 2-dimensional membranes, supporting fractionalized string excitations attached to the boundaries of open membranes. At finite temperature, the model can then be described as a gas of closed strings in a background of fluctuating membranes. We demonstrate that the emergent gauge structure of the low-temperature phase is naturally captured in the formalism of 2-form electrodynamics, which describes 1-dimensional charged strings coupled to a rank-2 anti-symmetric gauge field. After establishing the classical spin vorticity model, we consider perturbing it with quantum exchange interactions, from which we derive an effective membrane exchange model of the quantum dynamics of these membranes, which maps to a frustrated 2-form U(1) lattice gauge theory. We show the existence of a fine-tuned Rokhsar-Kivelson point where the quantum ground state is an equal weight superposition of all classical ground state configurations. We further demonstrate how to quantize the string excitations, by coupling a 1-form string field to the emergent 2-form U(1) gauge field, thus mapping a quantum spin model to a 2-form gauge-Higgs model. We discuss the stability of the gapless deconfined phase of this gauge theory and the possibility of realizing a novel class of phases of quantum matter: 2-form U(1) quantum spin liquids.Comment: 42 pages, 18 figures, 1 tabl

A combination of metabolites predicts adherence to the Mediterranean diet pattern and its associations with insulin sensitivity and lipid homeostasis in the general population: The Fenland Study, United Kingdom

BACKGROUND: Cardiometabolic benefits of the Mediterranean diet have been recognized, but underlying mechanisms are not fully understood. OBJECTIVES: We aimed to investigate how the Mediterranean diet could influence circulating metabolites and how the metabolites could mediate the associations of the diet with cardiometabolic risk factors. METHODS: Among 10,806 participants (58.9% women, mean age = 48.4 y) in the Fenland Study (2004-2015) in the United Kingdom, we assessed dietary consumption with FFQs and conducted a targeted metabolomics assay for 175 plasma metabolites (acylcarnitines, amines, sphingolipids, and phospholipids). We examined cross-sectional associations of the Mediterranean diet score (MDS) and its major components with each metabolite, modeling multivariable-adjusted linear regression. We used the regression estimates to summarize metabolites associated with the MDS into a metabolite score as a marker of the diet. Subsequently, we assessed how much metabolite subclasses and the metabolite score would mediate the associations of the MDS with circulating lipids, homeostasis model assessment of insulin resistance (HOMA-IR), and other metabolic factors by comparing regression estimates upon adjustment for the metabolites. RESULTS: Sixty-six metabolites were significantly associated with the MDS (P ≤ 0.003, corrected for false discovery rate) (Spearman correlations, r: -0.28 to +0.28). The metabolite score was moderately correlated with the MDS (r = 0.43). Of MDS components, consumption of nuts, cereals, and meats contributed to variations in acylcarnitines; fruits, to amino acids and amines; and fish, to phospholipids. The metabolite score was estimated to explain 37.2% of the inverse association of the MDS with HOMA-IR (P for mediation < 0.05). The associations of the MDS with cardiometabolic factors were estimated to be mediated by acylcarnitines, sphingolipids, and phospholipids. CONCLUSIONS: Multiple metabolites relate to the Mediterranean diet in a healthy general British population and highlight the potential to identify a set of biomarkers for an overall diet. The associations may involve pathways of phospholipid metabolism, carnitine metabolism, and development of insulin resistance and dyslipidemia

GreenMed: A sustainable physical activity tracking application

Evidence suggests that physical activity brings substantial health benefits while its absence causes several health issues. As people become more aware of negative health outcomes associated with physical inactivity, the shift from sedentary lifestyles to healthier ones occurs, and physical activity tracking apps may help in this regard. While mobile applications for tracking physical activity are abundant, most of of them fail to deliver evidence-based recommendations. This is a major drawback especially when these apps are designed to guide users towards healthy lifestyles. This paper presents a prototype application that could provide evidence-based recommendations about how much physical activity adults should do to stay healthy according to the user’s current activity level. A new visualisation approach which uses animal representations for activity levels is also introduced to enhance user experience, increase motivation and create a good base for further integration of gamification principles. Early testing showed that users found the prototype very useful and expressed great interest towards the animal representations

Recent progress on (3-Aminopropyl)triethoxysilane (APTES) functionalized-adsorbent for CO2 capture

The increasing emission of carbon dioxide (CO2) to the atmosphere has gained worldwide concern due to its main contribution to climate changes, global warming, and the greenhouse effect. Numbers of technologies have been carried out to remove this hazardous gas from the environment such as absorption, adsorption, membrane separation, cryogenic separation, and the biological process. Due to limitation of the current absorption technique, CO2 adsorption technique using porous solid adsorbents seems to be a potential candidate in capturing CO2. This is due to the advantages such as low regeneration energy requirements, no liquid waste and low cost. Furthermore, amine functionalization such as APTES on solid adsorbents has been progressively study for the usage of enhancing CO2 adsorption. The uses of adsorbents that modified with APTES could enhance the CO2 adsorption performance due to the chemisorption of -NH2 bond from the amine that further improve the CO2 adsorption performance in terms of the CO2 uptake and selectivity. Besides that, functionalization of APTES on adsorbent will also greatly enhance the reactivity towards CO2. In this review, the impact of the diverse amine loadings on different adsorbents and the type of solvent used for APTES-functionalization towards CO2 capture performance was thoroughly elaborated. The suitable reaction conditions and the regenerability of the adsorbents that could significantly affect their CO2 adsorption capacity were also discussed in detail. Other than distributing useful knowledge on the current progress of the APTES-functionalization adsorbents, this review is anticipated to provide benefit for the industrial and academic usage and appeal more attention in this fascinating area of CO2 capture

UTILIZING DPLOT, SEDLOG, AND ARCGIS PRO TO ENHANCE GEOLOGIC FIELD SKILLS: ROSENDALE, ULSTER COUNTY NEW YORK

Capstone geologic field mapping courses in undergraduate geoscience programs aim to compliment the academic knowledge with technical field skills. As a pilot study, these tools were used to collect field data using folded lower Paleozoic to mid-Paleozoic sedimentary outcrops consisting of clastic, non-clastic and occasional mixed siliciclastics in Rosendale, Ulster County, New York. Rosendale is known for its classic geological outcrops with variable structural, stratigraphic, paleontological and sedimentological complexities – ideal for a field mapping course. Traditionally, students’ data acquisition in the field and its subsequent laboratory analysis to produce a final geologic field report utilized acetate overlays to produce geologic maps, stratigraphic sections, and cross sections. However, the transition into digital mapping has been a challenge due to the limited resources, software access, and adequate technical training. Nevertheless, a recent experiment in utilizing simple-interface softwares such as sedlog, Dplot, and ArcGIS Pro result in additional techniques that enhance data acquisition, graphic representation, and geological interpretation. Employing ArcGIS Pro to initiate geologic field layouts and digital geologic maps enabled students to optimize the accuracy of measurements and geologic correlation of both limited and well-spaced outcrops. Dplot capability of constructing geomorphic profiles to project folding and faulting has provided students with an opportunity to reconstruct the past geological settings and draw conclusions pertaining to the development of the sedimentary basin over time. Constructing stratigraphic type sections via Sedlog generated digital data projections with paleocurrents, sedimentary facies, and stratal thickness. In addition to generating maps and reports suitable for undergraduate research presentation, integrating this software spiked students’ enthusiasm and readiness for conducting geologic fieldwork and, ultimately to pursue higher education and training in geospatial technologies

Associations between food group intakes and circulating insulin-like growth factor-I in the UK Biobank: a cross-sectional analysis

PURPOSE: Circulating insulin-like growth factor-I (IGF-I) concentrations have been positively associated with risk of several common cancers and inversely associated with risk of bone fractures. Intakes of some foods have been associated with increased circulating IGF-I concentrations; however, evidence remains inconclusive. Our aim was to assess cross-sectional associations of food group intakes with circulating IGF-I concentrations in the UK Biobank. METHODS: At recruitment, the UK Biobank participants reported their intake of commonly consumed foods. From these questions, intakes of total vegetables, fresh fruit, red meat, processed meat, poultry, oily fish, non-oily fish, and cheese were estimated. Serum IGF-I concentrations were measured in blood samples collected at recruitment. After exclusions, a total of 438,453 participants were included in this study. Multivariable linear regression was used to assess the associations of food group intakes with circulating IGF-I concentrations. RESULTS: Compared to never consumers, participants who reported consuming oily fish or non-oily fish ≥ 2 times/week had 1.25 nmol/L (95% confidence interval:1.19–1.31) and 1.16 nmol/L (1.08–1.24) higher IGF-I concentrations, respectively. Participants who reported consuming poultry ≥ 2 times/week had 0.87 nmol/L (0.80–0.94) higher IGF-I concentrations than those who reported never consuming poultry. There were no strong associations between other food groups and IGF-I concentrations. CONCLUSIONS: We found positive associations between oily and non-oily fish intake and circulating IGF-I concentrations. A weaker positive association of IGF-I with poultry intake was also observed. Further research is needed to understand the mechanisms which might explain these associations

Kinetic properties of ASC protein aggregation in epithelial cells

A poptosis-associated s peck-like protein with C ARD domain (ASC), an adaptor protein composed of caspase recruitment and pyrin domains, can efficiently self-associate to form a large spherical structure, called a speck. Although ASC aggregation is generally involved with both inflammatory processes and apoptosis, the detailed dynamics of speck formation have not been characterized. In this report, speck formation in HeLa cells transfected with ASC is examined by time-lapse live-imaging by confocal laser scanning microscopy. The results show that ASC aggregation is a very rapid and tightly regulated process. Prior to speck formation, soluble ASC aggregation is a low probability event, and the affinity of ASC subunits for one another is very low. Following a speck nucleation event, the affinity for further addition of ASC subunits increases dramatically, and aggregation is a highly energetically favorable reaction (Gibbs free energy ∼ −40 kJ/mol). This leads to a rapid depletion of soluble ASC, making it highly unlikely that a second speck will form inside the same cell and assuring that speck formation is “all or none,” with a well-defined end point. Comparison with kinetic models of the aggregation process indicates diffusion, instead of active transport, is the dominant process for speck growth. Though speck formation and aggresome formation share some properties, we show that the two processes are distinct. J. Cell. Physiol. 222: 738–747, 2010. © 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64555/1/22005_ftp.pd

Association of leukocyte DNA methylation changes with dietary folate and alcohol intake in the EPIC study

BACKGROUND: There is increasing evidence that folate, an important component of one-carbon metabolism, modulates the epigenome. Alcohol, which can disrupt folate absorption, is also known to affect the epigenome. We investigated the association of dietary folate and alcohol intake on leukocyte DNA methylation levels in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Leukocyte genome-wide DNA methylation profiles on approximately 450,000 CpG sites were acquired with Illumina HumanMethylation 450K BeadChip measured among 450 women control participants of a case-control study on breast cancer nested within the EPIC cohort. After data preprocessing using surrogate variable analysis to reduce systematic variation, associations of DNA methylation with dietary folate and alcohol intake, assessed with dietary questionnaires, were investigated using CpG site-specific linear models. Specific regions of the methylome were explored using differentially methylated region (DMR) analysis and fused lasso (FL) regressions. The DMR analysis combined results from the feature-specific analysis for a specific chromosome and using distances between features as weights whereas FL regression combined two penalties to encourage sparsity of single features and the difference between two consecutive features. RESULTS: After correction for multiple testing, intake of dietary folate was not associated with methylation level at any DNA methylation site, while weak associations were observed between alcohol intake and methylation level at CpG sites cg03199996 and cg07382687, with qval = 0.029 and qval = 0.048, respectively. Interestingly, the DMR analysis revealed a total of 24 and 90 regions associated with dietary folate and alcohol, respectively. For alcohol intake, 6 of the 15 most significant DMRs were identified through FL. CONCLUSIONS: Alcohol intake was associated with methylation levels at two CpG sites. Evidence from DMR and FL analyses indicated that dietary folate and alcohol intake may be associated with genomic regions with tumor suppressor activity such as the GSDMD and HOXA5 genes. These results were in line with the hypothesis that epigenetic mechanisms play a role in the association between folate and alcohol, although further studies are warranted to clarify the importance of these mechanisms in cancer