Solvation Dynamics of Thermoresponsive Polymer Films: The Influence of Salt Series in Water and Mixed Water/Methanol Atmosphere.

Understanding the salt effects on solvation behaviors of thermoresponsive polymers is crucial for designing and optimizing responsive systems suitable for diverse environments. In this work, the effect of potassium salts (CHCOOK, KCl, KBr, KI, and KNO) on solvation dynamics of poly(4-(N-(3'-methacrylamidopropyl)-N,N-dimethylammonio) butane-1-sulfonate) (PSBP), poly(N-isopropylmethacrylamide) (PNIPMAM), and PSBP-b-PNIPMAM films is investigated under saturated water and mixed water/methanol vapor via advanced in situ neutron/optical characterization techniques. These findings reveal that potassium salts enhance the films' hygroscopicity or methanol-induced swellability.

BNPLA: borated plastic for 3D-printing of thermal and cold neutron shielding.

3D printing technologies such as fused filament fabrication (FFF) offer great opportunities to enable the fabrication of complex geometries without access to a workshop or knowledge of machining. By adding filler materials to the raw filaments used for FFF, the material properties of the plastic can be adapted. With the addition of neutron absorbing particles, filaments can be created that enable 3D printing of neutron shielding with arbitrary geometry.

Polarized neutron imaging at NeXT (neutron and x-ray tomograph) at Institut Laue Langevin.

This work describes the implementation of polarized neutron imaging capabilities at the neutron and x-ray tomograph (NeXT) imaging station of the Institut Laue Langevin. This development enhances the capacity of this instrument to study advanced magnetic materials, which are crucial in a variety of engineering applications. Here, the feasibility of polarized neutron imaging at NeXT is demonstrated by visualizing the magnetic field generated by a simple bar magnet.

Observation by SANS and PNR of pure Néel-type domain wall profiles and skyrmion suppression below room temperature in magnetic [Pt/CoFeB/Ru] multilayers.

We report investigations of the magnetic textures in periodic multilayers [Pt(1 nm)/(CoFeB(0.8 nm)/Ru(1.4 nm)] using polarised neutron reflectometry (PNR) and small-angle neutron scattering (SANS).

Integrative genome-scale analyses reveal post-transcriptional signatures of early human small intestinal development in a directed differentiation organoid model.

Background: MicroRNAs (miRNAs) are important post-transcriptional gene regulators controlling cellular lineage specification and differentiation during embryonic development, including the gastrointestinal system. However, miRNA-mediated regulatory mechanisms involved in early embryonic development of human small intestine (SI) remains underexplored. To explore candidate roles for miRNAs in prenatal SI lineage specification in humans, we used a multi-omic analysis strategy in a directed differentiation model that programs human pluripotent stem cells toward the SI lineage.

Kinetics of UV Radiation-Induced Fast Collapse and Recovery in Thermally Cycled and Rehydrated Light- and Thermo- Double-Responsive Copolymer Films Probed by Neutron Reflectivity.

The kinetics of UV radiation-induced fast collapse and recovery in thermally cycled and rehydrated light- and thermo- double-responsive copolymer films of poly(oligo(ethylene glycol) methyl ether methacrylate--6-(4-phenylazophenoxy)hexyl acrylate), abbreviated as P(OEGMA--PAHA), are probed by neutron reflectivity (NR). The copolymer film is exposed to a thermal treatment starting at a temperature of 60 °C, which is well above its transition temperature (TT = 53 °C) before the temperature is rapidly decreased from 60 to 23 °C. Based on the applied protocol, the initially collapsed P(OEGMA--PAHA) film is rehydrated due to the switching of polymer chains from a more hydrophobic to a more hydrophilic state when the temperature falls below its TT.

Adherence of the rotating vortex lattice in the noncentrosymmetric superconductor RuBto the London model.

The noncentrosymmetric superconductor RuBhas in previous studies demonstrated remarkably unusual behaviour in its vortex lattice (VL), where the nearest neighbour directions of the vortices dissociate from the crystal lattice and instead show a complex field-history dependence, and the VL rotates as the field is changed. In this study, we look at the VL form factor of RuBduring this field-history dependence, to check for deviations from established models, such as the London model. We find that the data is well described by the anisotropic London model, which is in accordance with theoretical predictions that the alterations to the structure of the vortices due to broken inversion symmetry should be small.

α-Synuclein fibril and synaptic vesicle interactions lead to vesicle destruction and increased lipid-associated fibril uptake into iPSC-derived neurons.

Monomeric alpha-synuclein (aSyn) is a well characterised protein that importantly binds to lipids. aSyn monomers assemble into amyloid fibrils which are localised to lipids and organelles in insoluble structures found in Parkinson's disease patient's brains. Previous work to address pathological aSyn-lipid interactions has focused on using synthetic lipid membranes, which lack the complexity of physiological lipid membranes.

The Topology of Polymer Brushes Determines Their Nanoscale Hydration.

Time-of-flight neutron reflectometry (ToF-NR) performed under different relative humidity conditions demonstrates that polymer brushes constituted by hydrophilic, cyclic macromolecules exhibit a more compact conformation with lower roughness as compared to linear brush analogues, due to the absence of dangling chain ends extending at the polymer-vapor interface. In addition, cyclic brushes feature a larger swelling ratio and an increased solvent uptake with respect to their linear counterparts as a consequence of the increased interchain steric repulsions. It is proposed that differences in swelling ratios between linear and cyclic brushes come from differences in osmotic pressure experienced by each brush topology.

Small-angle neutron scattering study of mesoscale magnetic disordering and skyrmion phase suppression in the frustrated chiral magnet CoZnMn.

Co-Zn-Mn chiral cubic magnets display versatile magnetic skyrmion phases, including equilibrium phases stable far above and far below room temperature, and the facile creation of robust far-from-equilibrium skyrmion states. In this system, compositional disorder and magnetic frustration are key ingredients that have profound effects on the chiral magnetism. Reported here are studies of the magnetism in CoZnMn by magnetometry, small-angle neutron scattering (SANS), magnetic diffuse neutron scattering and Lorentz transmission electron microscopy (LTEM).

Effect of Thermal Stimulus on Kinetic Rehydration of Thermoresponsive Poly(diethylene glycol monomethyl ether methacrylate)--poly(poly(ethylene glycol) methyl ether methacrylate) Thin Films Probed by In Situ Neutron Reflectivity.

The kinetic rehydration of thin di-block copolymer poly(diethylene glycol monomethyl ether methacrylate)--poly(poly(ethylene glycol) methyl ether methacrylate) (PO--PO) films containing two thermoresponsive components is probed by in situ neutron reflectivity (NR) with different thermal stimuli in the DO vapor atmosphere. The transition temperatures (TTs) of PO and PO blocks are 25 and 60 °C, respectively. After the one-step stimulus (rapid decrease in temperature from 60 to 20 °C), the film directly switches from a collapsed to a fully swollen state.

Poly(sulfobetaine)-Based Diblock Copolymer Thin Films in Water/Acetone Atmosphere: Modulation of Water Hydration and Co-nonsolvency-Triggered Film Contraction.

The water swelling and subsequent solvent exchange including co-nonsolvency behavior of thin films of a doubly thermo-responsive diblock copolymer (DBC) are studied via spectral reflectance, time-of-flight neutron reflectometry, and Fourier transform infrared spectroscopy. The DBC consists of a thermo-responsive zwitterionic (poly(4-((3-methacrylamidopropyl) dimethylammonio) butane-1-sulfonate)) (PSBP) block, featuring an upper critical solution temperature transition in aqueous media but being insoluble in acetone, and a nonionic poly(-isopropylmethacrylamide) (PNIPMAM) block, featuring a lower critical solution temperature transition in water, while being soluble in acetone. Homogeneous DBC films of 50-100 nm thickness are first swollen in saturated water vapor (HO or DO), before they are subjected to a contraction process by exposure to mixed saturated water/acetone vapor (HO or DO/acetone-d6 = 9:1 v/v).

Field-induced vortex-like textures as a probe of the critical line in reentrant spin glasses.

We study the evolution of the low-temperature field-induced magnetic defects observed under an applied magnetic field in a series of frustrated amorphous ferromagnets (Fe[Formula: see text]Mn[Formula: see text])[Formula: see text]P[Formula: see text]B[Formula: see text]Al[Formula: see text] ("a-Fe[Formula: see text]Mn[Formula: see text]"). Combining small-angle neutron scattering and Monte Carlo simulations, we show that the morphology of these defects resemble that of quasi-bidimensional spin vortices. They are observed in the so-called "reentrant" spin-glass (RSG) phase, up to the critical concentration [Formula: see text] which separates the RSG and "true" spin glass (SG) within the low temperature part of the magnetic phase diagram of a-FeMn.

Multiomic analysis defines the first microRNA atlas across all small intestinal epithelial lineages and reveals novel markers of almost all major cell types.

MicroRNA-mediated regulation is critical for the proper development and function of the small intestinal (SI) epithelium. However, it is not known which microRNAs are expressed in each of the cell types of the SI epithelium. To bridge this important knowledge gap, we performed comprehensive microRNA profiling in all major cell types of the mouse SI epithelium.

PGD2 and CRTH2 counteract Type 2 cytokine-elicited intestinal epithelial responses during helminth infection.

Type 2 inflammation is associated with epithelial cell responses, including goblet cell hyperplasia, that promote worm expulsion during intestinal helminth infection. How these epithelial responses are regulated remains incompletely understood. Here, we show that mice deficient in the prostaglandin D2 (PGD2) receptor CRTH2 and mice with CRTH2 deficiency only in nonhematopoietic cells exhibited enhanced worm clearance and intestinal goblet cell hyperplasia following infection with the helminth Nippostrongylus brasiliensis.

Hydration and Thermal Response Kinetics of a Cross-Linked Thermoresponsive Copolymer Film on a Hydrophobic PAN Substrate Coating Probed by Neutron Reflectivity.

The hydration and thermal response kinetics of the cross-linked thermoresponsive copolymer poly((diethylene glycol monomethyl ether methacrylate)--poly(ethylene glycol) methyl ether methacrylate), abbreviated as P(MEOMA--OEGMA), thin film on a hydrophobic polyacrylonitrile (PAN) substrate coating, which resembles a synthetic fabric, is probed by neutron reflectivity (NR). The PAN and monomer (MEOMA and OEGMA) solutions are sequentially spin-coated onto a silicon (Si) substrate. Afterward, plasma treatment is applied to realize the cross-linking of PAN and monomers.

Graphite intercalation compound (GIC) crystal monochromators for cold neutron instruments: Characterization of KC by time-of-flight neutron diffraction.

Graphite intercalation compounds (GICs) are a group of layered materials that are suitable as monochromators for cold neutrons. KC is a particularly interesting compound in this regard as it features a large c-axis lattice spacing of 8.74 Å, high reflectivity, and the possibility to produce large crystals with mosaicity that matches the beam divergence of cold neutron guides.

Abnormal fast dehydration and rehydration of light- and thermo-dual-responsive copolymer films triggered by UV radiation.

Abnormal fast dehydration and rehydration of light- and thermo-dual-responsive copolymer films of poly(oligo(ethylene glycol) methyl ether methacrylate-co-6-(4-phenylazophenoxy)hexyl acrylate), abbreviated as P(OEGMA300-co-PAHA), are triggered by UV radiation. Both rapid kinetic processes are probed by in situ neutron reflectivity (NR). The transition temperatures (TTs) of P(OEGMA300-co-PAHA) are 53.

Impact of Thermal History on the Kinetic Response of Thermoresponsive Poly(diethylene glycol monomethyl ether methacrylate)--poly(poly(ethylene glycol)methyl ether methacrylate) Thin Films Investigated by In Situ Neutron Reflectivity.

The impact of thermal history on the kinetic response of thin thermoresponsive diblock copolymer poly(diethylene glycol monomethyl ether methacrylate)--poly(poly(ethylene glycol) methyl ether methacrylate), abbreviated as PMEOMA--POEGMA, films is investigated by in situ neutron reflectivity. The PMEOMA and POEGMA blocks are both thermoresponsive polymers with a lower critical solution temperature. Their transition temperatures (TTs) are around 25 °C (TT, PMEOMA) and 60 °C (TT, POEGMA).

Elevated circulating Th2 but not group 2 innate lymphoid cell responses characterize canine atopic dermatitis.

Atopic dermatitis (AD) is an allergic skin disease that causes significant morbidity and affects multiple species. AD is highly prevalent in companion dogs, and the clinical management of the disease remains challenging. An improved understanding of the immunologic and genetic pathways that lead to disease could inform the development of novel treatments.

Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe.

We report the discovery of topological magnetism in the candidate magnetic Weyl semimetal CeAlGe. Using neutron scattering we find this system to host several incommensurate, square-coordinated multi-k[over →] magnetic phases below T_{N}. The topological properties of a phase stable at intermediate magnetic fields parallel to the c axis are suggested by observation of a topological Hall effect.

Magnetic Guinier law.

Small-angle scattering of X-rays and neutrons is a routine method for the determination of nanoparticle sizes. The so-called Guinier law represents the low- approximation for the small-angle scattering curve from an assembly of particles. The Guinier law has originally been derived for nonmagnetic particle-matrix-type systems and it is successfully employed for the estimation of particle sizes in various scientific domains ( soft-matter physics, biology, colloidal chemistry, materials science).

Thermoresponsive Diblock Copolymer Films with a Linear Shrinkage Behavior and Its Potential Application in Temperature Sensors.

The linear shrinkage behavior in thermoresponsive diblock copolymer films and its potential application in temperature sensors are investigated. The copolymer is composed of two thermoresponsive blocks with different transition temperatures (TTs): di(ethylene glycol) methyl ether methacrylate (MEOMA; TT = 25 °C) and poly(ethylene glycol) methyl ether methacrylate (OEGMA; TT = 60 °C) with a molar ratio of 1:1. Aqueous solutions of PMEOMA--POEGMA show a three-stage transition upon heating as seen with optical transmittance and small-angle X-ray scattering: dissolution (T < TT), self-assembled micelles with core-shell structure (TT < T < TT), and aggregation of collapsed micelles (T > TT).