Developmentally regulated extinction of Ly-49 receptor expression permits maturation and selection of NK1.1+ T cells

Clonally distributed inhibitory receptors negatively regulate natural killer (NK) cell function via specific interactions with allelic forms of major histocompatibility complex (MHC) class I molecules. In the mouse, the Ly-49 family of inhibitory receptors is found not only on NK cells but also on a minor (NK1.1+) T cell subset. Using Ly-49 transgenic mice, we show here that the development of NK1.1+ T cells, in contrast to NK or conventional T cells, is impaired when their Ly-49 receptors engage self-MHC class I molecules. Impaired NK1.1+ T cell development in transgenic mice is associated with a failure to select the appropriate CD1-reactive T cell receptor repertoire. In normal mice, NK1.1+ T cell maturation is accompanied by extinction of Ly-49 receptor expression. Collectively, our data imply that developmentally regulated extinction of inhibitory MHC-specific receptors is required for normal NK1.1+ T cell maturation and selection.     

Impulse Density Measurements after the Held Method

The introduction shows the importance of the impulse on damage, if the high explosive amount is smaller than 1000 kg.     

Effect of hydrolyzed collagen on thermal,mechanical and biological properties of poly(lactic acid) bionanocomposites

Iranian Polymer Journal - Bionanocomposites based on poly(lactic acid) (PLA), plasticized with commercial tributyl o-acetyl citrate (ATBC) and containing hydrolyzed collagen (HC) up to...     

Increasing the folate content in Egyptian baladi bread using germinated wheat flour

The main objective of this study was to increase the folate content in Egyptian baladi bread using germinated wheat flour (GWF). The effect of germination temperature and drying conditions on the folate content of wheat grains was studied. Wheat flour was substituted with unsieved and sieved GWF at different levels and the effects on folate content and the rheological properties of dough were determined. Germination of wheat grains resulted in a 3- to 4-fold higher folate content depending on the germination temperature. Maximum folate content (61 μg/100 g dry matter (DM)) occurred at 30 °C. Drying did not affect folate content in germinated grains. After replacement with GWF, folate content in both flour and bread increased 1.5- to 4-fold depending on the level of replacement. Rheological properties of dough were adversely affected by increasing replacement level (as determined by farinograph). While the folate content in bread was as high as 66 μg/100 g DM at complete replacement of flour with sieved GWF, the bread was dark and layers were not separated. After replacement of half of the flour with sieved GWF (50 g/100 g), the baladi bread was acceptable with respect to colour and layer separation. The folate content in this bread was 50 μg/100 g DM, compared with 30 μg/100 g DM in bread without GWF (0 g/100 g).     

Does thermal control improve visual satisfaction? Interactions between occupants’ self-perceived control,visual, thermal,and overall satisfaction

Occupants’ satisfaction had been researched independently related to thermal and visual stimuli for many decades showing among others the influence of self-perceived control. Few studies revealed interactions between thermal and visual stimuli affecting occupant satisfaction. In addition, studies including interactions between thermal and visual stimuli are lacking different control scenarios. This study focused on the effects of thermal and visual factors, their interaction, seasonal influences, and the degree of self-perceived control on overall, thermal, and visual satisfaction. A repeated-measures laboratory study with 61 participants running over two years and a total of 986 participant sessions was conducted. Mixed model analyses with overall satisfaction as outcome variable revealed that thermal satisfaction and visual satisfaction are the most important predictors for overall satisfaction with the indoor environment. Self-perceived thermal control served as moderator between thermal satisfaction and overall satisfaction. Season had slight influence on overall satisfaction. Random effects explained the highest amount of variance, indicating that intra- and interindividual differences in the ratings of satisfaction are more prevalent than study condition. Future building design and operation plans aiming at a high level of occupant satisfaction should consider personal control opportunities and take into account the moderating effect of control opportunities in multimodal interactions.     

Terahertz Heterodyne Array Receivers for Astronomy

Journal of Infrared, Millimeter, and Terahertz Waves - We review the development of multi-pixel heterodyne receivers for astronomical research in the submillimeter and terahertz spectral domains....     

Solidification of hesperidin nanosuspension by spray drying optimized by design of experiment (DoE)

Objective: To accelerate the determination of optimal spray drying parameters, a “Design of Experiment” (DoE) software was applied to produce well redispersible hesperidin nanocrystals.

Significance: For final solid dosage forms, aqueous liquid nanosuspensions need to be solidified, whereas spray drying is a large-scale cost-effective industrial process.

Methods: A nanosuspension with 18% (w/w) of hesperidin stabilized by 1% (w/w) of poloxamer 188 was produced by wet bead milling. The sizes of original and redispersed spray-dried nanosuspensions were determined by laser diffractometry (LD) and photon correlation spectroscopy (PCS) and used as effect parameters. In addition, light microscopy was performed to judge the redispersion quality.

Results: After a two-step design of MODDE 9, screening model and response surface model (RSM), the inlet temperature of spray dryer and the concentration of protectant (polyvinylpyrrolidone, PVP K25) were identified as the most important factors affecting the redispersion of nanocrystals. As predicted in the RSM modeling, when 5% (w/w) of PVP K25 was added in an 18% (w/w) of hesperidin nanosuspension, subsequently spray-dried at an inlet temperature of 100?°C, well redispersed solid nanocrystals with an average particle size of 276?nm were obtained. By the use of PVP K25, the saturation solubility of the redispersed nanocrystals in water was improved to 86.81?µg/ml, about 2.5-fold of the original nanosuspension. In addition, the dissolution velocity was accelerated.

Conclusions: This was attributed to the additional effects of steric stabilization on the nanocrystals and solubilization by the PVP polymer from spray drying.     

Engineered Ferritin for Magnetogenetic Manipulation of Proteins and Organelles Inside Living Cells

Magnetogenetics is emerging as a novel approach for remote‐controlled manipulation of cellular functions in tissues and organisms with high spatial and temporal resolution. A critical, still challenging issue for these techniques is to conjugate target proteins with magnetic probes that can satisfy multiple colloidal and biofunctional constraints. Here, semisynthetic magnetic nanoparticles are tailored based on human ferritin coupled to monomeric enhanced green fluorescent protein (mEGFP) for magnetic manipulation of proteins inside living cells. This study demonstrates efficient delivery, intracellular stealth properties, and rapid subcellular targeting of those magnetic nanoparticles via GFP–nanobody interactions. By means of magnetic field gradients, rapid spatial reorganization in the cytosol of proteins captured to the nanoparticle surface is achieved. Moreover, exploiting efficient nanoparticle targeting to intracellular membranes, remote‐controlled arrest of mitochondrial dynamics using magnetic fields is demonstrated. The studies establish subcellular control of proteins and organelles with unprecedented spatial and temporal resolution, thus opening new prospects for magnetogenetic applications in fundamental cell biology and nanomedicine.     

Additive manufacturing of copper alloys: influence of process parameters and alloying elements

Owing to the physical properties of copper and its alloys it is challenging to achieve good surface quality and low porosity by the widely used laser-based additive manufacturing processes. This paper deals with the role of alloy composition, powder size and process parameters in additive manufacturing with laser beam melting machine (with power up to 100 W). Test parts were produced in pure copper and CuNiSi(Cr) alloys. The porosity was investigated as a function of different process parameters and powder size ranges. The effects of the alloy physical properties (reflectivity, thermal conductivity, melting range and surface tension) are discussed. Moreover, the effect of thermal treatment on the properties of CuNiSi parts was assessed in conventional two-step heat treatments.