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There is growing interest in polymers with high ionic conductivity for applications including batteries, fuel cells, and separation membranes. However, measuring ion diffusion in polymers can be challenging, requiring complex procedures and instrumentation. Here, a simple strategy to study ion diffusion in polymers is presented that utilizes ion-chromic spiropyan as an indicator to measure the diffusion of LiTFSI, KTFSI, and NaTFSI within poly(ethylene oxide)-based polymer networks. These systems are selected, as these are common ions and polymers used in energy storage applications, however, the approach described is not specific to materials for energy storage. Specifically, to enabling the study of ion diffusion, these salts cause the spiropyran to undergo an isomerization reaction, which results in a significant color change. This colorimetric response enables the determination of the diffusion coefficients of these ions within films of these polymers simply by optically tracking the spatial-temporal evolution of the isomerization product within the film and fitting the data to the relevant diffusion equations. The simplicity of the method makes it amenable to the study of ion diffusion in polymers under a range of conditions, including various temperatures and under macroscopic deformation.

Electrochemical phase transformation in ion-insertion crystalline electrodes is accompanied by compositional and structural changes, including the microstructural development of oriented phase domains. Previous studies have identified prevailingly transformation heterogeneities associated with diffusion- or reaction-limited mechanisms. In comparison, transformation-induced domains and their microstructure resulting from the loss of symmetry elements remain unexplored, despite their general importance in alloys and ceramics. Here, we map the formation of oriented phase domains and the development of strain gradient quantitatively during the electrochemical ion-insertion process. A collocated four-dimensional scanning transmission electron microscopy and electron energy loss spectroscopy approach, coupled with data mining, enables the study. Results show that in our model system of cubic spinel MnO

BACKGROUND & AIMSPrimary sclerosing cholangitis (PSC) is a rare chronic cholestatic liver disease characterized by multi-focal bile duct strictures. To date, underlying molecular mechanisms of PSC remain unclear and therapeutic options for PSC patients are limited. We performed cell-free messenger RNA (cf-mRNA) next generation sequencing (RNA-Seq) to characterize the circulating transcriptome of PSC and non-invasively investigate potentially bioactive signals that are associated with PSC.METHODSSerum cf-mRNA profiles were compared among 50 individuals with PSC, 20 healthy controls, and 235 individuals with non-alcoholic fatty liver disease (NAFLD). Tissue and cell type-of-origin genes that are dysregulated in subjects with PSC were evaluated. Subsequently, diagnostic classifiers were built using PSC dysregulated cf-mRNA genes.RESULTSDifferential expression analysis of the cf-mRNA transcriptomes of PSC and healthy controls resulted in identification of 1407 dysregulated genes. Furthermore, differentially expressed genes between PSC and the liver diseases (NAFL and Non-Alcohol Steatohepatitis (NASH)) or healthy controls shared common genes known to be involved in liver pathophysiology. In particular, genes from liver- and specific cell type-origin, including hepatocyte, hepatic stellate cells and Kupffer cells, were highly abundant in cf-mRNA of subjects with PSC. Gene cluster analysis revealed that liver-specific genes dysregulated in PSC form a distinct cluster which corresponded to a subset of the PSC subject population. Finally, we developed a cf-mRNA classifier using liver-specific genes which discriminated PSC from healthy control subjects using gene transcripts of liver origin.CONCLUSIONSBlood-based whole transcriptome cf-mRNA profiling revealed high abundance of liver-specific genes in PSC subject sera which may be used to diagnose PSC patients. We identified several unique cf-mRNA profiles of subjects with PSC. These findings may also have utility for non-invasive molecular stratification of subjects with PSC for pharmacotherapy safety and response studies.Graphical Abstract

Background: High-quality carbohydrate sources, such as whole grains, have been associated with a lower risk of type 2 diabetes (T2D), whereas low-quality carbohydrate sources, such as refined grains and added sugar, have been associated with a higher T2D risk. However, few studies have considered how replacing dietary carbohydrate with other macronutrients may influence T2D risk. Objective: We examined whether isocaloric substitution of high- or low-quality carbohydrate for fat, protein, and their subtypes is associated with T2D risk. Methods: We included 75,430 women from the Nurses' Health Study (1984-2016), 85,630 women from the Nurses' Health Study II (1991-2017), and 40,261 men from the Health Professionals Follow-Up Study (1986-2016) who were free of T2D, CVD, and cancer at baseline. Dietary data were collected every 2-4 years using a validated, semi-quantitative food frequency questionnaire. High-quality carbohydrate was defined as carbohydrate from whole grains, fruits, vegetables, and legumes. Low-quality carbohydrate was defined as carbohydrate from refined grains, added sugars, and potatoes. We used Cox proportional hazards regression with time-varying covariates to model the substitution of 5% of energy intake from high- and low-quality carbohydrate for isocaloric amounts of fat, protein, and their subtypes [polyunsaturated fat (PUFA), animal and plant monounsaturated fat (MUFA), saturated fat, trans fat, and animal and plant protein]. Cohort-specific estimates were combined using inverse variance-weighted fixed effects meta-analyses. Results: During 4,859,845 years of follow-up, we documented 20,141 incident T2D cases. In multivariable-adjusted meta-analyses, isocaloric substitution of high-quality carbohydrate for total fat [HR (95% CI) 0.94 (0.93, 0.96)], total MUFA [0.95 (0.91, 0.98)], MUFA from animal sources [0.92 (0.88, 0.95)], total protein [0.91 (0.89, 0.94)], or animal protein [0.94 (0.91, 0.97] was associated with a lower T2D risk. On the other hand, the substitution of low-quality carbohydrate for plant MUFA [1.06 (1.02-1.10)] or plant protein [1.06 (1.02-1.11)] was associated with a higher risk of T2D. When we restricted high-quality carbohydrate sources to whole grains, the results were similar or stronger. Additionally, substitution of whole grain carbohydrate for saturated fat [0.87 (0.84, 0.91)], trans fat [0.87 (0.83, 0.92)], PUFA [0.88 (0.84, 0.92)], plant MUFA [0.92 (0.87, 0.96)], or plant protein [0.91 (0.86, 0.97)] was associated with lower T2D risk. Conclusions: The effect of carbohydrate substitution on T2D risk depends not only on the nutrient being substituted but also on the quality of the carbohydrate. Substitution of high-quality carbohydrate, especially carbohydrate from whole grains (i.e. whole wheat bread, oatmeal), for fat or protein, especially animal sources (i.e. beef, poultry), may lower T2D risk.

We have optimized the method for simultaneous extraction of ethyl methylphosphonic acid ester (EMPA), isopropyl methylphosphonic acid ester (IPMPA), isobutyl methylphosphonic acid ester (IBMPA), pinacolyl methylphosphonic acid ester (PMPA), and methylphosphonic acid (MPA) from soil with their further determination by high performance liquid chromatography — high-resolution tandem mass spectrometry (HPLC — HRMS/MS). The analytes are highly-polar products of nerve agent hydrolysis. The observed ions in the fragmentation mass spectra of deprotonated molecules of EMPA, IPMPA, IBMPA, PMPA, MPA, and their corresponding deuterated molecules, as well as possible structural formulas of fragment ions are presented. Liquid extraction with deionized water followed by concentration by evaporation is used to prepare soil samples for analysis. Separation of the components was carried out using reverse-phase chromatography. The time required for sample preparation and analysis of soil samples does not exceed 1 hour. The detection limits in soil were 0.05 ng/g for EMPA and IPMPA, 0.02 ng/g for IBMPA and PMPA, and 1 ng/g for MPA.

This is an integrated experimental and theoretical study of the dynamics and rheology of self-crosslinked, slightly charged, temperature responsive soft Poly(N-isopropylacrylamide) (pNIPAM) microgels over a wide range of concentration and temperature spanning the sharp change in particle size and intermolecular interactions across the lower critical solution temperature (LCST). Dramatic, non-monotonic changes in viscoelasticity are observed with temperature, with distinctive concentration dependences in the dense fluid, glassy, and soft-jammed states. Motivated by our experimental observations, we formulate a minimalistic model for the size dependence of a single microgel particle and the change of interparticle interaction from purely repulsive to attractive upon heating. Using microscopic equilibrium and time-dependent statistical mechanical theories, theoretical predictions are quantitatively compared with experimental measurements of the shear modulus. Good agreement is found for the nonmonotonic temperature behavior that originates as a consequence of the competition between reduced microgel packing fraction and increasing interpar-ticle attractions. Testable predictions are made for nonlinear rheological properties such as the yield stress and strain. To the best of our knowledge, this is the first attempt to quantitatively understand in a unified manner the viscoelasticity of dense, temperature-responsive microgel suspensions spanning a wide range of temperatures and concentrations., additional supplementary information provided

Detection of biologically active components in mixtures of complex composition which include biological fluids (blood, urine, etc.) is the most difficult problem of the analytical chemistry and requires the use of modern highly informative research methods. One of the most effective and universal ways to study the structure of unknown substances is the method of liquid chromatography- high resolution mass spectrometry that combines the possibility of highly selective separation of the mixtures under study, the reliable detection of unknown substances and high sensitivity of the procedure. We propose a method for the simultaneous extraction of highly polar biomarkers of nitrogen mustard — N-triethanolamine (TEA), N-ethyl diethanolamine (EDEA) and N-methyldiethanolamine (MDEA) — from urine with subsequent determination by HPLC and detection by high resolution tandem mass spectrometry. The mass spectra of fragmentation of protonated molecular ions of TEA, EDEA, and MDEA have been studied and possible structural formulas of the fragment ions are given. The sample preparation of urine and mass spectrometric detection in the multiple reaction monitoring mode were optimized. The five-fold dilution with deionized water was chosen as a method of urine sample preparation for analysis. Separation of the components was performed in the reversed-phase chromatography mode with retention times for TEA, EDEA, and MDEA of 2.00, 2.05, and 1.92 min, respectively. The time required to complete all steps of the urine sample analysis did not exceed 25 min. The detection limits in urine were 1 ng/ml for TEA and 2 ng/ml for EDEA and MDEA. The developed approach provides determination of the fact of application of specific nitrogen mustard in enquiry of possible exposure of living organism to the blister agents.

BACKGROUND: Drug hypersensitivity is an adverse reaction caused by immune or non-immune mechanisms to the intake of adequate doses of drugs. To avoid a dangerous situation, correctly collected pharmacological history, taking into account all the characteristics of the patient (gender, age, concomitant pathology), and knowledge of the mechanism of action of drugs can help a practicing physician who does not currently have a reliable method for diagnosing drug hypersensitivity. AIM: Identification of age-specific drug intolerance. MATERIALS AND METHODS: The study was conducted from 2017 to 2020 and included 200 outpatient medical history forms of individuals diagnosed with an unspecified pathological reaction to a drug or medication. All drug reactions were based on patients own statements and were allocated as dichotomous variables. The results were analyzed by nonparametric statistics (Pearsons chi-square). RESULTS: Three groups of patients were identified: 1844 years (n=49), 4560 years (n=60), 61 (n=91). The odds of incomprehensible reactions were 2.2 times higher in patients in group 3 than in patients in the other groups. Group 3 patients were 12 times more likely to have an itchy reaction to medications than patients in the other groups. Group 1 patients were 3 times more likely to have urticaria than patients in groups 2 and 3. The odds of drug intolerance to angiotensin-converting enzyme (ACE) inhibitors were 2.6 times higher in patients in group 3 than in patients in the other groups. When comparing clinical manifestations of drug intolerance to penicillin and cephalosporin antibiotics, no significant differences were found in all patients. The presence of allergies and somatic pathology of 3 systems did not significantly affect the possibility of reactions of varying severity to 3 drugs in these groups. CONCLUSIONS: Patients age has no effect on the possibility of reactions to certain groups of drugs. The exception was ACE inhibitors, which is most likely due to the higher frequency of prescribing antihypertensive therapy in patients in this age group. The aggravation of clinical manifestations and the occurrence of polypharmacy are not associated with age and comorbid background. Age and non-life-threatening clinical manifestations of drug intolerance were correlated, which indicates the absence of the reliable effect of age on the possibility of anaphylactic shock or angioedema.

Realization of high energy density Li-ion anodes is a significant challenge due to the volume changes generally exhibited by such systems during charge and discharge. Here, three-dimensional inverse opal (3D-IO) mesostructured Ni@TiO2@RGO electrodes were fabricated by templating nickel electrodeposition with self-assembled, three dimensionally ordered polystyrene (PS) opals, followed by atomic layer deposition (ALD) of TiO2 and spray coating of reduced graphene oxide (RGO). The electrode delivers initial discharge and charge volumetric capacities of 2082 mAh cm-3 and 1873 mAh cm-3 at 0.5 C, respectively. The composite electrode exhibits volumetric discharge and charge capacities of 1508 mAh cm-3 and 1504 mAh cm-3 at 0.5 C after 200 cycles and good rate capacity up to at least 10 C. The almost unbroken 3D-IO mesostructure after 200 lithiation and delithiation cycles demonstrates the excellent structural stability of the 3D-IO electrode design concept. The enhanced volumetric capacity and structural stability originate from high active materials loading, the short and efficient ion and electron pathways, and the composite structure provided by the nickel electrodeposition, ALD, and RGO spray coating electrode preparation process, as well as that both TiO2 and RGO participate in lithium storage.

Aqueous polymer colloids known as latexes are widely used in coating applications. Multicomponent latexes comprised of two incompatible polymeric species organized into a core-shell particle morphology are a promising system for self-stratifying coatings that spontaneously partition into multiple layers, thereby yielding complex structured coatings requiring only a single application step. Developing new materials for self-stratifying coatings requires a clear understanding of the thermodynamic and kinetic properties governing phase separation and polymeric species transport. In this work, we study phase separation and self-stratification in polymer films based on multicomponent acrylic (shell) and acrylic-silicone (core) latex particles. Our results show that the molecular weight of the shell polymer and heat aging conditions of the film critically determine the underlying transport phenomena, which ultimately controls phase separation in the film. Unentangled shell polymers result in efficient phase separation within hours with heat aging at reasonable temperatures, whereas entangled shell polymers effectively inhibit phase separation even under extensive heat aging conditions over a period of months due to kinetic limitations. Transmission electron microscopy is used to track morphological changes as a function of thermal aging. Interestingly, our results show that the rheological properties of the latex films are highly sensitive to morphology, and linear shear rheology is used to understand morphological changes. Overall, these results highlight the importance of bulk rheology as a simple and effective tool for understanding changes in morphology in multicomponent latex films.

Interfaces have crucial, but still poorly understood, roles in the performance of secondary solid-state batteries. Here, using crystallographically oriented and highly faceted thick cathodes, we directly assess the impact of cathode crystallography and morphology on the long-term performance of solid-state batteries. The controlled interface crystallography, area and microstructure of these cathodes enables an understanding of interface instabilities unknown (hidden) in conventional thin-film and composite solid-state electrodes. A generic and direct correlation between cell performance and interface stability is revealed for a variety of both lithium- and sodium-based cathodes and solid electrolytes. Our findings highlight that minimizing interfacial area, rather than its expansion as is the case in conventional composite cathodes, is key to both understanding the nature of interface instabilities and improving cell performance. Our findings also point to the use of dense and thick cathodes as a way of increasing the energy density and stability of solid-state batteries. Interfaces play crucial, but still poorly understood, roles in the performance of secondary solid-state batteries. Using crystallographically oriented and highly faceted thick cathodes, the impact of cathode crystallography and morphology on long-term performance is investigated.

For 20 years, nanoscale 3D printing has been based on two-photon absorption, requiring expensive pulsed lasers. Now, via a two-step absorption process, such printing has been demonstrated using a low-cost, low-power continuous-wave laser diode, showing the potential for dramatic cost reductions in 3D nanoprinting.

While there is no known fundamental lower limit to the thermal conductivity of a material, the lowest thermal conductivities are typically found in amorphous and strongly disordered materials, not ...

Here, we report a solid-phase approach to synthesize azobenzene and spiropyran derivatives. The divergent synthesis process requires no purification steps to obtain the desired product with a 28-55% yield, depending on the specific compound. For the spiropyran compounds, solid-phase resin cleavage is performed under mild conditions to minimize spiropyran ring opening. The solid-phase method enables the synthesis of a library of azobenzene and spiropyran derivatives without the need to develop purification strategies for each derivative.

A paradigm for enhanced magnetorheological elastic materials is introduced and experimentally established. We show that a nonlinearly stiffening polymer matrix can be exploited to achieve anomalous magneto-elastomer stiffening exceeding standard magneto-elastomer theory and experiment in terms of percentage stiffness change and sensitivity to applied magnetic flux. Using a model system of a semiflexible fibrin network embedded with micron sized carbonyl iron particles, we demonstrate that even at a modest particle volume fraction (0.5-4%), a coupling between the magnetically interacting dipoles and a strain-stiffening polymer mesh provides previously unexplored opportunities for material design. Our experiments indicate that confined particles within the fibrin network internally tension and stiffen the polymer mesh when an external field is applied, resulting in a field-dependent stiffening response from the polymer mesh that superposes with the magnetic interparticle interactions.

For the first time, an “Evaporated-Nitrogen” Minimally Intensive Layer Delamination (EN-MILD) synthesis approach is reported to synthesize exceptionally high quality MXene sheets. In the EN-MILD method, the concentrations of acids and Li-ions are continuously increased during the etching process. By implementing the EN-MILD approach, the electrical conductivity increases up to 2.4 × 104 S cm−1, which is the highest reported value to date for Ti3C2Tx MXenes (a traditional MILD approach results in a conductivity of 5.8 × 103 S cm−1). This significant improvement in electrical conductivity arises from the high quality of the synthesized MXene sheets as well as a larger flake size. The EN-MILD synthesis approach also offers high yield of delaminated single MXene layers (up to ∼60% after the first round of washing/centrifugation) and high colloidal concentrations (up to 31 mg ml−1). The working electrode prepared from free-standing MXene paper shows an exceptional capacitance of ≈490 F g−1 at 1 A g−1 in a supercapacitor, which is among the highest values reported for MXene-based supercapacitor electrodes. The exceptional electrical conductivity, high yield of delaminated MXene single layers, and high colloidal concentration of the EN-MILD approach significantly expand the applications of MXenes.

Organic molecules with redox-active motifs have attracted great attention as next-generation electrodes for sustainable energy storage. While there has been significant progress in designing redox-active molecules, the practical requirements of high electrochemical activity and stability, as well as rapid kinetics for fast charging, are motivating a search for methods to engineer three-dimensional (3D) structures of organic-based electrodes. Here, we demonstrate a lithographic fabrication strategy for realizing a 3D bicontinuous nano-network consisting of a periodically porous nickel-supported redox-active polyimide layer (pore radius

High collared pottery rim sherds from sites designated as Huron-Wendat and St. Lawrence Iroquoian are analysed using a community of practice approach. Using several analytical methods on the same ceramic sherds, we aimed to determine the technological choices made by potters. We focused specifically on clay selection, temper selection and processing, preparation of the clay body and formation of the rim. Our findings demonstrate that for each step in the production process there are a range of practices represented within the study region. However, comparison with adjacent areas and earlier periods shows that there is consistency in technological choices that are specific to our study area. We argue that this is consistent with connections between the pottery making traditions in the Simcoe Uplands in Ontario and the St. Lawrence Valley areas. As traditions were maintained by people, so we envision connected communities across the study area.

We proposed a method for determining the presence of trace amounts of adducts of isopropylmethylphosphonic acid (IMPA) and cyclohexylmethylphosphonic acid (CMPA), biomarkers of exposure to sarin and cyclosarin in a body, with a tripeptide (Tyr-Thr-Lys). The method is based on plasma trypsinolysis with the formation of stable adducts IMPA–Tyr-Thr-Lys and СMPA–Tyr-Thr-Lys and their detection by high-performance liquid chromatography (HPLC) with high-resolution tandem mass spectrometry detection. The following conditions for the sample preparation of human blood plasma exposed to sarin and cyclosarin were optimized: aliquot portion volume, enzymatic hydrolysis conditions, mass spectrometric detection (selection of optimal pairs of ion reactions and detection modes), and gradient elution programs in the HPLC separation of the test mixture. The limit of detection for sarin and cyclosarin in human blood plasma was 5 ng mL–1. The proposed approach was tested in the analysis of blood plasma samples submitted to analysis in the framework of the Fourth Official Biomedical Test of the Organization for the Prohibition of Chemical Weapons; the results showed good determination specificity.

A multipurpose reagent, p-methoxyphenacyl bromide, is proposed for the derivatization of polar products of the degradation (markers) of nerve agents, which allows their determination by high-performance liquid chromatography with tandem mass spectrometric detection or by gas chromatography in combination with high-resolution mass spectrometry. The reaction conditions for the derivatization of alkylphosphonic and alkylmethylphosphonic acids with this reagent were optimized, the features and general patterns of the formation of MS1 and MS2 spectra of derivates were found, and the conditions for their chromatographic separation by two independent methods were selected. The limits of detection reached are in the range from 0.02 to 0.2 ng/mL for high-performance liquid chromatography with tandem mass spectrometric detection and from 10 to 50 ng/mL for gas chromatography with tandem mass spectrometric detection.