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Impact of g-Load Shift on Temporal Expression Pattern of Apoptosis-linked Proteins in the Rat Mammary Gland

Abstract

Alteration in gravitational load impacts homeorhetic response in rat dams which affects neonatal pup survival. However, the effects of hypergravity (HG) exposure on the abundance of apoptosis-associated proteins in mammary epithelial cells (MECs) have not been characterized. Therefore, we examined whether chronic exposure to HG from midpregnancy alters the abundance of proapoptotic proteins in MECs during the late pregnancy and early lactation. A group of pregnant Sprague Dawley rats were exposed to either HG (2g) or normo-gravity (1g: stationary control [SC]) from days 11 to 20 of gestation (G20). Another set of animals were investigated from day 11 of pregnancy through days 1 and 3 (P1 and P3, respectively) postpartum. Quantitative (pixels [px]/lobule) immunohistochemistry at G20 of Cleaved Caspase-3 (CC-3), Tumor Protein p53 (P53), and vitamin D receptor (VDR) revealed that all the three proteins were increased (p<0.01) in HG rats compared to SC animals. At P1, the HG group had twofold higher (p<0.001) expression of CC-3 relative to the SC group. Approximately, 50% (p<0.001) more VDR was detected in the HG cohorts than SC at P3. These results suggest that a shift in g-load upregulates the expression of key proapoptotic proteins during the pregnancy-to-lactation transition in the rat MECs.

Open access
Musculoskeletal Outcomes from Chronic High-Speed High-Impact Resistive Exercise

Abstract

Subjects (n=13) did 30 workouts with their left leg on an Inertial Exercise Trainer (IET), while their right leg served as an untreated control. Before and after the 30 workouts, they underwent isokinetic strength tests (knee and ankle extensors of both legs) whose peak torque (PT), time to PT (TTPT), and rate of torque development (RTD) values were each analyzed with 2(leg)×2(time)×3(velocity) analysis of variances (ANOVAs), with repeated measures per independent variable. Peak force (PF) and total work (TW) data were measured from each IET workout, and they represent time course strength changes produced by our exercise intervention. PF and TW values for the three IET exercises that comprised each workout were each analyzed with one-way ANOVAs with time as the independent variable. Results included significant ankle and knee extensor PT increases, whereby the left leg achieved higher values at posttesting, but there were no significant TTPT changes and a time effect for ankle extensor RTD. Our data show that PF and TW each had significant increases over time, with the latter exhibiting greater gains over the 30-workout intervention. Our results imply that the IET yields strength gains over time comparable to standard resistive exercise hardware.

Open access
Challenges of ERAU’s First Suborbital Flight Aboard Blue Origin’s New Shepard M7 for the Cell Research Experiment In Microgravity (CRExIM)

Abstract

Cell Research Experiment In Microgravity (CRExIM) was launched aboard Blue Origin’s New Shepard suborbital vehicle on Tuesday, December 12, 2017, from the West Texas Launch Site in Van Horn, Texas. One of the aims of this science experiment was to assess the effects of microgravity on murine T-cells during suborbital flight. These cells were placed in a NanoLab with a data logger that sensed the acceleration, temperature, and relative humidity during preflight, flight, and postflight operations. Some discrepancies in sensor measurement were noticed, and these errors were attributed partly to the difference in sampling rates and partly to the different locations of the sensors, which made it difficult to obtain highly accurate measurements of the accelerations and to correlate both sets of data. This paper discusses the setbacks and lessons learned, which made our team find new alternatives while meeting all milestones as mandated by NanoRacks and Blue Origin. This manuscript highlights these alternatives that led to the success of the mission and gives recommendations that will enable customers to alleviate some of these challenges in future flights.

Open access
Ab initio study of GdCo5 magnetic and magneto-optical properties

Abstract

The full potential linearized augmented plane wave method (FLAPW) including the spin-orbit coupling has been used to study the structural, electronic and magnetic properties of GdCo5 compound. The calculations were performed within the local spin density approximation (LSDA) as well as Coulomb corrected LSDA + U approach. The study revealed that the LSDA + U method gave a better representation of the band structure, density of states and magnetic moments than LSDA. It was found that the spin magnetic moment of Co (2c) and Co (3g) atoms in the studied compound is smaller compared to the one in bulk Co. The optical and magneto-optical properties and the magneto-optical Kerr effect have also been investigated.

Open access
Adsorption and gas sensing properties of CuFe2O4 nanoparticles

Abstract

Spinel ferrite nanoparticles in the form CuFe2O4 were tested for gas sensing applications. Nanoparticles pressed in a disk form were used to construct conductometric gas sensors. The disk was placed between two electrical electrodes wherein the top electrode had a grid structure. The produced sensors were tested against H2S and H2 gases and they were found to be selective and sensitive to H2S concentration as low as 25 ppm. The composition of the nanoparticles was confirmed by X-ray diffraction and energy dispersive X-ray spectroscopy measurements. The crystal structure was verified by both X-ray diffraction and transmission electron microscope. The observations obtained from the experiments demonstrated the high potential of using CuFe2O4 nanoparticles for H2S sensing applications.

Open access
Analysis of the implementation of the identification system for directly marked parts - DataMatrix code

Abstract

A photocode in Polish is a common name for a two-dimensional code, which is characterized by higher information capacity than a traditional barcode. The paper analyses the use of the two-dimensional coding system - DataMatrix to identify and classify the material stream in the production process. The analysis showed the effectiveness of the implementation of the coding system in the context of increased availability, machine use and increased product quality. The improvement in the production process is confirmed by an increase in the OEE index. As part of further improvement measures, the coding system should be implemented throughout the enterprise, its compatibility with existing systems should be ensured and applied to all products.

Open access
Characterization of the native oxide on CdTe surfaces

Abstract

This study focuses on the description of oxidation of CdTe monocrystal surfaces after selective chemical etching. Measurements of surface morphology of the oxides occurring in short time are valuable for deeper understanding of the material degradation and fabrication of reliable devices with enhanced performance. The samples with (1 1 1) orientation were selectively etched and cleaned of oxide. Exposure of the oxide-free surfaces of CdTe to air at normal atmospheric conditions over 24 hours leads to an appearance of characteristic surface features. The oxidized surfaces were investigated by scanning electron microscopy, scanning probe microscopy, Raman spectroscopy and ellipsometry. The results indicate clear differences in the oxidation of Cd-terminated and Te-terminated surfaces.

Open access
Correlation between surface morphology and potential profile in OFETs with zone-cast TIPS-Pentacene as seen by scanning Kelvin probe microscopy

Abstract

Charge-carrier transport in the channel of bottom gate, top contact organic field effect transistors with anisotropic layers of 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-Pentacene) obtained by zone casting was investigated using scanning Kelvin probe microscopy combined with atomic force microscopy. The TIPS-Pentacene continuous layers consisted of thin crystals unidirectionally oriented in the channel. Devices with perpendicular and parallel charge flow in the transistor channel were prepared. It was found that irregularities in the surface morphology at the semiconductor layer in the transistor channel are correlated with the local potential profile, and that the channel resistance strongly depends on the orientation of the TIPS-Pentacene crystals.

Open access
The delocalization of production to Poland

Abstract

This paper presents some aspects of the process of services, products and manufacturing transfer, with the associated production resources, from other locations and plants to Poland.

The study was carried out on the basis of an analysis of publications about delocalization as well as by means of desk research, where there were used the accessible primary and secondary data such as branch reports, statistical data available in reports, data bases, and information accessible on Polish and European websites. The article is also the result of the author's experience of participation in the relocation of a number of international companies, regarding various industries. Delocalization in Poland was presented both from the point of view of Conceptualizing delocalization (literature review, theoretical position) and Implementation of production.

The delocalization mainly takes advantage of labor forces. On the other hand, it may also concern innovative activities and develop high-tech for regions affected by economic restructuring. The social policies for the risk mitigation of the delocalization of production are also being developed and implemented. This work clarifying the conditions of delocalization in Poland and highlight the important roles played by innovation and institutions for achieving sustainability.

Open access
Dielectric properties of Bi-substituted LDHs synthesized by co-precipitation and sol-gel methods

Abstract

Magnesium-aluminum-bismuth layered double hydroxides (Mg3Al1−xBix; LDHs) were prepared using both coprecipitation and sol-gel methods. For the preparation of Mg/Al/Bi LDH by the co-precipitation method, the appropriate amounts of dissolved starting materials (Al(NO3)3 · 9H2O, Mg(NO3)2 · 6H2O and Bi(NO3)3 · 5H2O) were mixed with a solution of NaHCO3:NaOH. In the sol-gel processing, the precursor Mg–Al–Bi–O gels were synthesized using the same starting materials and ethylene glycol as complexing agent. The mixed-metal oxides obtained by subsequent heating of Mg–Al–Bi–O gels at 650 °C were reconstructed to Mg3Al1−xBix LDHs in water at 80 °C. All the synthesized products were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and dielectric measurements.

Open access