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High-yield production of lignin nanoparticle photonic glasses

Lignin has emerged as a sustainable alternative to fossil-based polymers in advanced materials such as photonics. However, current methods for preparing photonic lignin materials are limited by non-benign organic solvents and low production yields. In this work, we present a highly efficient process that enables the production of photonic glasses with yields ranging from 48% to 72%, depending on t

Theoretical and instructional aspects of learning with visualizations

Multimedia environments consist of verbal and visual representations that, if appropriately processed, allow for the construction of an integrated mental model of the content. Whereas much is known on how students learn from verbal representations, there are fewer insights regarding the processing of visual information, alone or in conjunction with text. This chapter uses a semiotics approach to p

Weak population structure in the North American house wren Troglodytes aedon

Cryptic genetic differentiation is being increasingly documented in birds and other organisms using genome-wide variation. A recent example of cryptic genetic differentiation in a widespread species with conserved morphology is the northern house wren Troglodytes aedon. We found that, despite extremely similar morphology and no documented vocal differences, the two subspecies of the northern house

A Low-Cost Method for Characterizing the Inception and Extent of Cavitation in High-Pressure Homogenizers

High-pressure homogenizers are prone to cavitation, which causes wear and influences breakup efficiency. However, the inception point, as well as the extent and intensity, depends on geometry, operation, and fluid properties. While several methods have been previously suggested to characterize cavitation in homogenizer valves (including ultrasonic methods), they have required highly specialized, s

OSL dating of glacial outburst flood deposits in NE Poland and their bleaching problem inferred from the landform-sediment associations and regional context

A continental-type glacial flood termed the Suwałki megafloods took place in NE Poland during the last glaciation and significantly transformed the proglacial area. This study aims, for the first time, to establish the chronology of this flood. Twenty-two sediment samples from two meltwater spillways were dated by optically stimulated luminescence. Sixteen ages from the flood megadunes are between

Welfare Conditionality and Social Identity Effect Mechanisms and the Case of Immigrant Support

The present paper discusses the effects of social identity and self-determination theory and highlights their relevance for welfare conditionality with respect to individual behaviour and well-being. While welfare conditionality may provide economic incentives for certain desired behaviours, e.g., active job search, it is argued that their impact on the claimants’ social self-construal and identit

Pulmonary delivery of antimicrobial peptides

Anna Fureby, PhD, Group Manager & Senior Scientist, Life Science, and Ulla Elofsson, PhD, Senior Scientist, both of SP Technical Research Institute of Sweden, and Per Gerde, PhD, Chief Scientific Officer, Inhalation Sciences Sweden, discuss the serious problem of antibiotic resistance and the potential role of antimicrobial peptides in the treatment of resistant bacterial strains. For pulmonar

UV-B degradation affects nanoplastic toxicity and leads to release of small toxic substances

Fragmented micro- and nanoplastics are widespread pollutants with adverse effects on the environment. However, the breakdown process does not end with micro- and nanoplastics but is expected to continue until carbon dioxide has been formed. During this process the plastics will undergo chemical changes and small molecules may be released. We have broken down small amine-modified (∅53 nm) and carbo

Amyloid-β and tau deposition in traumatic brain injury : a study of Vietnam War veterans

Traumatic brain injury is widely viewed as a risk factor for dementia, but the biological mechanisms underlying this association are still unclear. In previous studies, traumatic brain injury has been associated with the hallmark pathologies of Alzheimer's disease, i.e. amyloid-β plaques and neurofibrillary tangles comprised of hyperphosphorylated tau. Depending on the type and location of trauma,

A generalist vector-transmitted parasite exhibits population genetic structure among host genera

Generalist parasites experience selective pressures from the various host species they infect. However, it is unclear if parasite transmission among host species precludes the establishment of host-specific adaptations and population genetic structure. We assessed the population genetic structure of the vector-transmitted avian haemosporidian parasite Haemoproteus majoris (lineage WW2; n = 34 infe

Tablet mechanics depend on nano and micro scale adhesion, lubrication and structure

Tablets are the most convenient form for drug administration. However, despite the ease of manufacturing problems such as powder adhesion occur during the production process. This study presents surface and structural characterization of tablets formulated with commonly used excipients (microcrystalline cellulose (MCC), lactose, mannitol, magnesium (Mg) stearate) pressed under different compaction

Aqueous Two-Phase Systems for Microencapsulation in Food Applications

This chapter deals with aqueous two-phase systems, which are formed spontaneously when two polymers are mixed in water as a common solvent. Such phase-separated systems have potential as microencapsulation systems, although the major focus in research has been (bio)separation applications. Added components, such as proteins, large molecules, whole cells, and emulsion droplets, tend to partition pr

Relationships between solid dispersion preparation process, particle size and drug release - An NMR and NMR microimaging study

Solid dispersion tablets prepared by either spray drying or rotoevaporation and exhibiting different grain and pore sizes were investigated under the process of hydration-swelling-gelation. 2H and 1H NMR microimaging experiments were used to selectively follow water penetration and polymer mobilization kinetics, respectively, while the drug release kinetics was followed by 1H NMR spectroscopy. The

Polymer-drug interactions and wetting of solid dispersions

We demonstrate the ability of drugs to influence the wetting of solid dispersion tablets in unexpected ways. Five model drugs of different water solubility and ability to interact with the involved polymers were incorporated in hydrophilic polymer matrices, made of either hydroxypropyl methylcellulose (HPMC) or polyvinyl pyrrolidone (PVP). The physical mixtures of all combinations of drug and poly

Approaches to encapsulation of active food ingredients in spray-drying

Microencapsulation can be used to improve the stability and control the release of dried active food ingredients such as flavors, enzymes, probioticas and oxidation sensitive oils. Spray-drying can be used for encapsulation and powder generation in one step by utilizing different phenomena that occur during drying. Dry emulsion is a classic way to supply encapsulated flavors and protect oxidation

Adsorption of pharmaceutical excipients onto microcrystals of siramesine hydrochloride : Effects on physicochemical properties

A common challenge in the development of new drug substances is poor dissolution characteristics caused by low aqueous solubility. In this study, microcrystals with optimized physicochemical properties were prepared by precipitation in the presence of excipients, which adsorbed to the particle surface and altered particle size, morphology, and dissolution rate. The poorly water-soluble drug sirame

Surface composition and contact angle relationships for differently prepared solid dispersions

Solid dispersions are promising drug delivery forms which offer the possibility to disperse a hydrophobic drug in a hydrophilic matrix and thereby improve the dissolution behavior and the bioavailability of the drug. One important aspect and a prerequisite in understanding the drug dissolution mechanism from solid dispersions is a better analytical monitoring of the solid dispersion surface proper

Polymer mobilization and drug release during tablet swelling. A 1H NMR and NMR microimaging study

The objective of this study was to investigate the swelling characteristics of a hydroxypropyl methylcellulose (HPMC) matrix incorporating the hydrophilic drug antipyrine. We have used this matrix to introduce a novel analytical method, which allows us to obtain within one experimental setup information about the molecular processes of the polymer carrier and its impact on drug release. Nuclear ma