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Climatic variation drives loss and restructuring of carbon and nitrogen in boreal forest wildfire

The boreal forest landscape covers approximately 10% of the earth's land area and accounts for almost 30 % of the global annual terrestrial sink of carbon (C). Increased emissions due to climate-change-amplified fire frequency, size, and intensity threaten to remove elements such as C and nitrogen (N) from forest soil and vegetation at rates faster than they accumulate. This may result in large ar

In situ X-ray reflectivity and GISAXS study of mesoporous silica films grown from sodium silicate solution precursors

An environmentally friendly and inexpensive silica source, sodium silicate solution, was applied to synthesize a free-standing mesoporous silica film at the air/liquid interface, exploiting the co-assembly of cetyltrimethylammonium bromide and polyethylenimine. The effect of the composition of the solution used for the film formation on the mesostructure of the as-synthesized silica films, charact

The interaction of styrene maleic acid copolymers with phospholipids in Langmuir monolayers, vesicles and nanodiscs; a structural study

Hypothesis: Self-assembly of amphipathic styrene maleic acid copolymers with phospholipids in aqueous solution results in the formation of ‘nanodiscs’ containing a planar segment of phospholipid bilayer encapsulated by a polymer belt. Recently, studies have reported that lipids rapidly exchange between both nanodiscs in solution and external sources of lipids. Outstanding questions remain regardin

Neutron Diffraction Study of Indole Solvation in Deep Eutectic Systems of Choline Chloride, Malic Acid, and Water

Deep eutectic systems are currently under intense investigation to replace traditional organic solvents in a range of syntheses. Here, indole in choline chloride-malic acid deep eutectic solvent (DES) was studied as a function of water content, to identify solute interactions with the DES which affect heterocycle reactivity and selectivity, and as a proxy for biomolecule solvation. Empirical Poten

Fluorescent styrene maleic acid copolymers to facilitate membrane protein studies in lipid nanodiscs

Fluorescently-labelled variants of poly(styrene-co-maleic acid), SMA, have been synthesised by RAFT copolymerisation. We show that low ratios of vinyl fluorophores, analogous to styrene, can be successfully incorporated during polymerisation without detriment to nanodisc formation upon interaction with lipids. These novel copolymers are capable of encapuslating lipids and the model membrane protei

Cellulose Microbeads : Toward the Controlled Release of Nutrients to Plants

The use of conventional fertilizers is associated with pollution due to leaching and a mismatch between release rates and crop requirements for optimal development. Slow-release fertilizers could address both problems. Here, the synthesis and properties of a zinc fertilizer composed of cellulose microbeads loaded with aqueous ZnSO4 are reported for the first time. UV-vis spectrophotometry showed t

Stable Cellulose Nanofibril Microcapsules from Pickering Emulsion Templates

Electrostatic attractions are essential in any complex formation between the nanofibrils of the opposite charge for a specific application, such as microcapsule production. Here, we used cationized cellulose nanofibril (CCNF)-stabilized Pickering emulsions (PEs) as templates, and the electrostatic interactions were induced by adding oxidized cellulose nanofibrils (OCNFs) at the oil-water interface

Membrane extraction with styrene-maleic acid copolymer results in insulin receptor autophosphorylation in the absence of ligand

Extraction of integral membrane proteins with poly(styrene-co-maleic acid) provides a promising alternative to detergent extraction. A major advantage of extraction using copolymers rather than detergent is the retention of the lipid bilayer around the proteins. Here we report the first functional investigation of the mammalian insulin receptor which was extracted from cell membranes using poly(st

Styrene-Maleic Acid Copolymer Nanodiscs to Determine the Shape of Membrane Proteins

Lipid nanodiscs can be used to solubilize functional membrane proteins (MPs) in nativelike environments. Thus, they are promising reagents that have been proven useful to characterize MPs. Both protein and non-protein molecular belts have shown promise to maintain the structural integrity of MPs in lipid nanodiscs. Small-angle neutron scattering (SANS) can be used to determine low-resolution struc

Ab initio reconstruction of small angle scattering data for membrane proteins in copolymer nanodiscs

Background: Small angle scattering techniques are beginning to be more widely utilised for structural analysis of biological systems. However, applying these techniques to study membrane proteins still remains problematic, due to sample preparation requirements and analysis of the resulting data. The development of styrene-maleic acid co-polymers (SMA) to extract membrane proteins into nanodiscs f

A Developmental Approach to Assessing and Treating Agrammatic Aphasia

Purpose: There is mounting evidence that the agrammatism that defines Broca’s aphasia can be explained in processing terms. However, the extant approach simply describes agrammatism as disparate deficits in a static, mature system. This tutorial aims to motivate and outline a developmental alternative. This alternative is processability theory (PT), a root-to-apex theory of language development, w

Liposuction and Controlled Compression Therapy Reduce the Erysipelas Incidence in Primary and Secondary Lymphedema

Background: Skin infections are a recurring problem for people with lymphedema, and lymphedema has been proven to be the single most important risk factor for developing erysipelas in the leg. This study aimed to determine whether liposuction for late-stage lymphedema reduces the rate of erysipelas in lower extremity lymphedema. Methods: One-hundred twenty-four patients with a median age of 49 yea

Automation of Modeling and Calibration of Integrated Preparative Protein Chromatography Systems

With the increasing global demand for precise and efficient pharmaceuticals and the biopharma industry moving towards Industry 4.0, the need for advanced process integration, automation, and modeling has increased as well. In this work, a method for automatic modeling and calibration of an integrated preparative chromatographic system for pharmaceutical development and production is presented. Bas

First-order like phase transition induced by quenched coupling disorder

We investigate the collective dynamics of a population of X Y model-type oscillators, globally coupled via non-separable interactions that are randomly chosen from a positive or negative value and subject to thermal noise controlled by temperature T. We find that the system at T = 0 exhibits a discontinuous, first-order like phase transition from the incoherent to the fully coherent state; when th

Continuous rotary membrane emulsification for the production of sustainable Pickering emulsions

A continuous rotary membrane emulsification (cRME) system, allowing the decoupling of droplet generation from continuous phase (CP) flowrate, is presented here for the first time. The decoupling results in higher productivity and greater control compared to traditional crossflow and rotational membrane emulsification processes. A design of experiment (DoE) investigated the influence on droplet for

Disposable Coverslip for Rapid Throughput Screening of Malaria Using Attenuated Total Reflection Spectroscopy

Malaria is considered to be one of the most catastrophic health issues in the whole world. Vibrational spectroscopy is a rapid, robust, label-free, inexpensive, highly sensitive, nonperturbative, and nondestructive technique with high diagnostic potential for the early detection of disease agents. In particular, the fingerprinting capability of attenuated total reflection spectroscopy is promising

Recent progress in Pickering emulsions stabilised by bioderived particles

In recent years, the demand for non-surfactant based Pickering emulsions in many industrial applications has grown significantly because of the option to select biodegradable and sustainable materials with low toxicity as emulsion stabilisers. Usually, emulsions are a dispersion system, where synthetic surfactants or macromolecules stabilise two immiscible phases (typically water and oil phases) t

Keratin-Chitosan Microcapsules via Membrane Emulsification and Interfacial Complexation

The continuous fabrication via membrane emulsification of stable microcapsules using renewable, biodegradable biopolymer wall materials keratin and chitosan is reported here for the first time. Microcapsule formation was based on opposite charge interactions between keratin and chitosan, which formed polyelectrolyte complexes when solutions were mixed at pH 5.5. Interfacial complexation was induce

Development of Methodology to Investigate the Surface SMALPome of Mammalian Cells

Extraction of membrane proteins from biological membranes has traditionally involved detergents. In the past decade, a new technique has been developed, which uses styrene maleic acid (SMA) copolymers to extract membrane proteins into nanodiscs without the requirement of detergents. SMA nanodiscs are compatible with analytical techniques, such as small-angle scattering, NMR spectroscopy, and DLS,

Deep eutectic solvents—The vital link between ionic liquids and ionic solutions

When selecting a solvent for a given solute, the strongly held idiom “like dissolves like”, meaning that polar solvents are used for polar solutes, is often used. This idea has resulted from the concept that most molecular solvents are homogeneous. In a deep eutectic solvent (DES), however, both components can be ionic or non-ionic, polar or non-polar. By tuning the components, DESs can solubilize