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This study examines the impact of Tb and Zn doping on the Y-123 superconducting system by analyzing crack propagation mechanisms through Vickers microhardness measurements. The measurements are conducted at various application forces ranging from 0.245 N to 2.940 N. The microhardness measurements are used to determine the role of impurity addition on Vickers hardness, modulus of elasticity, brittleness index, fracture toughness, and yield strengths. It is found that impurity ions serving as strong barrier regions improve the surface residual compressive stress sites and interactivity between the adjacent layers. Similarly, the sensitivity to the external forces reduce significantly with the substitution mechanism due to the induced new slip systems and ionic bond formations. Accordingly, all the mechanical performance properties are recorded to increase significantly with the impurity ions. Especially, the replacement of Zn by Cu ions in the Y-123 matrix exhibits higher resistance to failure, mechanical strength, and stabilization of the durable tetragonal phase. Accordingly, Zn/Cu substitution in Y-123 ceramics paves the way for the applications of ceramic compounds in the fields of heavy-industrial technology and industrial power systems. All the ceramic materials also exhibit indentation size effect feature based on the recovery mechanism. Additionally, load-independent microhardness parameters are semi-empirically modeled by Meyer's law, Hays-Kendall, indentation-induced cracking, elastic–plastic deformation, and proportional sample resistance model for the first time. According to the comparisons, the IIC model is identified as the most suitable for interpreting the real microhardness results of newly produced Y-123 ceramic matrices. [ABSTRACT FROM AUTHOR]

A change to zero-emission drive systems in road freight transport is required to achieve climate protection targets. Therefore, alternative drive systems for road freight transport are being tested in field trials in Germany. One such technology is the eHighway system. The eHighway system combines an overhead contact line hybrid truck (OH truck) and an overhead contact line infrastructure. The objective of this study was to evaluate technical and operational success factors and barriers influencing the adoption of the eHighway system by freight transport companies. We evaluated expert interviews, written surveys, and vehicle data. We found that transport companies had no major restrictions concerning the technical equipment of the OH trucks. Furthermore, we found no operational restrictions in the use of OH trucks while the OH trucks can be integrated into different transport operations. [ABSTRACT FROM AUTHOR]

Ideal drug carriers feature a high loading capacity to minimize the exposure of patients with excessive, inactive carrier materials. The highest imaginable loading capacity could be achieved by nanocarriers, which are assembled from the therapeutic cargo molecules themselves. Here, we describe peptide nucleic acid (PNA)-based zirconium (Zr) coordination nanoparticles which exhibit very high PNA loading of > 94 % w/w. This metal-organic hybrid nanomaterial class extends the enormous compound space of coordination polymers towards bioactive oligonucleotide linkers. The architecture of single- or double-stranded PNAs was systematically varied to identify design criteria for the coordination driven self-assembly with Zr(IV) nodes at room temperature. Aromatic carboxylic acid functions, serving as Lewis bases, and a two-step synthesis process with preformation of Z r 6 O 4 (O H) 4 turned out to be decisive for successful nanoparticle assembly. Confocal laser scanning microscopy confirmed that the PNA-Zr nanoparticles are readily internalized by cells. PNA-Zr nanoparticles, coated with a cationic lipopeptide, successfully delivered an antisense PNA sequence for splicing correction of the β -globin intron mutation IVS2-705 into a functional reporter cell line and mediated splice-switching via interaction with the endogenous mRNA splicing machinery. The presented PNA-Zr nanoparticles represent a bioactive platform with high design flexibility and extraordinary PNA loading capacity, where the nucleic acid constitutes an integral part of the material, instead of being loaded into passive delivery systems. [ABSTRACT FROM AUTHOR]

Ideal drug carriers feature a high loading capacity to minimize the exposure of patients with excessive, inactive carrier materials. The highest imaginable loading capacity could be achieved by nanocarriers, which are assembled from the therapeutic cargo molecules themselves. Here, we describe peptide nucleic acid (PNA)-based zirconium (Zr) coordination nanoparticles which exhibit very high PNA loading of > 94 % w/w. This metal-organic hybrid nanomaterial class extends the enormous compound space of coordination polymers towards bioactive oligonucleotide linkers. The architecture of single- or double-stranded PNAs was systematically varied to identify design criteria for the coordination driven self-assembly with Zr(IV) nodes at room temperature. Aromatic carboxylic acid functions, serving as Lewis bases, and a two-step synthesis process with preformation of Z r 6 O 4 (O H) 4 turned out to be decisive for successful nanoparticle assembly. Confocal laser scanning microscopy confirmed that the PNA-Zr nanoparticles are readily internalized by cells. PNA-Zr nanoparticles, coated with a cationic lipopeptide, successfully delivered an antisense PNA sequence for splicing correction of the β -globin intron mutation IVS2-705 into a functional reporter cell line and mediated splice-switching via interaction with the endogenous mRNA splicing machinery. The presented PNA-Zr nanoparticles represent a bioactive platform with high design flexibility and extraordinary PNA loading capacity, where the nucleic acid constitutes an integral part of the material, instead of being loaded into passive delivery systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Human & Society / İnsannsan ve Toplum is the property of Scientific Studies Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Community & Physician / Toplum ve Hekim is the property of Turk Tabipleri Birligi / Turkish Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Human transferrin protein (Tf) modified polyplexes have already displayed encouraging potential for receptor‐mediated nucleic acid delivery into tumors. The use of a blood‐derived targeting protein and polydisperse macromolecular cationic subunits however presents a practical challenge for pharmaceutical grade production. Here, Tf receptor (TfR) targeted small interfering RNA (siRNA) polyplexes are designed that are completely composed of synthetic, monodisperse, and sequence‐defined subunits generated by solid‐phase supported synthesis. An optimized cationizable lipo‐oligoaminoamide (lipo‐OAA) is used for siRNA core polyplex formation, and a retro‐enantio peptide (reTfR) attached via a monodisperse polyethylene glycol (PEG) spacer via click chemistry is applied for targeting. Improved gene silencing is demonstrated in TfR‐expressing KB and DU145 cells. Analogous plasmid DNA (pDNA) polyplexes are successfully used for receptor‐mediated gene delivery in TfR‐rich K562 cells and Neuro2a cells. Six lipo‐OAAs differing in their lipidic domain and redox‐sensitive attachment of lipid residues are tested in order to evaluate the impact of core polyplex stability on receptor‐dependent gene transfer. [ABSTRACT FROM AUTHOR]

The crystallisation kinetics and effects of doping on Bi2Sr2CaCu2Oδ (BSCCO) glass ceramic system with 0.0%, 0.1%, 0.3% and 0.5% PbSe were investigated in this study. Differential thermal analysis (DTA) was used to investigate the effects of PbSe doping on glass transition, nucleation and crystallisation temperature of glass were investigated. The DTA results were analysed using the Ozawa, Augis–Bennett, Takhor and Kissinger equations for nucleation kinetics to determine the activation energies and Avrami parameters. Thermogravimetric analysis revealed that the amount of oxidation in the structure increased with increasing PbSe-doping concentration. [ABSTRACT FROM AUTHOR]

Copyright of CLIVATGE is the property of Universitat de Barcelona - Facultat d'Economia i Empresa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, the sol-gel method was preferred for the production of superconductor materials since it is known that the sol-gel method is useful in producing nanoparticles. The Zn(Zinc) doped YBCO-123 superconductor samples (YBa2Cu3-xZnxO) were produced. The main objective in the present study was to examine the effects of both of Zn doping and sol-gel method, which was chosen as the production method, on the structural, electrical, and mechanical properties of Y-123 superconductor materials. Especially, the effects of the nanoparticles and doping on the mechanical properties of materials were discussed over the bulk modulus. It was aimed to obtain information about the mechanical properties by comparing the bulk modules calculated theoretically and experimentally. Besides that, the XRD, SEM, and resistivity measurements were performed in order to characterize the structural and electrical properties. [ABSTRACT FROM AUTHOR]

BACKGROUND.: The load transfer between the implant-bone interface depends on various factors, including loading type; material properties of the implant and prosthesis; and implant geometry, length, diameter, and shape. OBJECTIVE.: The purpose of this study was to evaluate stress distribution in single tilted bone-level implants with different connections and peripheral bone under vertical and oblique loads using three-dimensional (3D) finite element analysis (FEA). METHOS.: 3D models of four different implant systems and their abutments were created from the data (computer-aided design) of original implants and abutments scanned with an optical scanner. The implants were placed in the bone block at degrees of 0°, 15°, and 30°. Then, a 3D model of the metal-ceramic crown was created and a 100-N total load was applied vertically and obliquely. RESULTS.: Stress analyses showed variable results depending on the connection design and tilting angle; however, the tube in tube (TIT) connection type exhibited lower stress values in most loading and tilting simulations. CONCLUSIONS.: Increase in tilting angle showed variable results in each connection design. The TIT connection design was found to be more successful in terms of stress distributions in the implant components and the peripheral bone. [ABSTRACT FROM AUTHOR]

Copyright of PRAKSIS is the property of PRAKSIS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND.: The load transfer between the implant-bone interface depends on various factors, including loading type; material properties of the implant and prosthesis; and implant geometry, length, diameter, and shape. OBJECTIVE.: The purpose of this study was to evaluate stress distribution in single tilted bone-level implants with different connections and peripheral bone under vertical and oblique loads using three-dimensional (3D) finite element analysis (FEA). METHOS.: 3D models of four different implant systems and their abutments were created from the data (computer-aided design) of original implants and abutments scanned with an optical scanner. The implants were placed in the bone block at degrees of 0°, 15°, and 30°. Then, a 3D model of the metal-ceramic crown was created and a 100-N total load was applied vertically and obliquely. RESULTS.: Stress analyses showed variable results depending on the connection design and tilting angle; however, the tube in tube (TIT) connection type exhibited lower stress values in most loading and tilting simulations. CONCLUSIONS.: Increase in tilting angle showed variable results in each connection design. The TIT connection design was found to be more successful in terms of stress distributions in the implant components and the peripheral bone. [ABSTRACT FROM AUTHOR]

Copyright of Respiratory Case Reports is the property of LookUs Scientific and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

PURPOSE. Although several surface treatments have been recently investigated both under in vitro and in vivo conditions, controversy still exists regarding the selection of the most appropriate zirconia surface pre-treatment. The purpose of this study was to evaluate the effect of alumina (Al) and aluminium nitride (AlN) coating on the shear bond strength of adhesive resin cement to zirconia core. MATERIALS AND METHODS. Fifty zirconia core discs were divided into 5 groups; air particle abrasion with 50 μm aluminum oxide particles (Al2O3), polishing + Al coating, polishing + AlN coating, air particle abrasion with 50 μm Al2O3 + Al coating and air particle abrasion with 50 μm Al2O3 + AlN coating. Composite resin discs were cemented to each of specimens. Shear bond strength (MPa) was measured using a universal testing machine. The effects of the surface preparations on each specimen were examined with scanning electron microscope (SEM). Data were statistically analyzed by one-way ANOVA (α=.05). RESULTS. The highest bond strengths were obtained by air abrasion with 50 μm Al2O3, the lowest bond strengths were obtained in polishing + Al coating group (P<.05). CONCLUSION. Al and AlN coatings using the reactive magnetron sputtering technique were found to be ineffective to increase the bond strength of adhesive resin cement to zirconia core. [ABSTRACT FROM AUTHOR]

The accuracy of an adaptive neurofuzzy computing technique in estimation of reference evapotranspiration (ET0) is investigated in this paper. The daily climatic data, solar radiation, air temperature, relative humidity, and wind speed from two stations, Pomona and Santa Monica, in Los Angeles, Calif., are used as inputs to the neurofuzzy model to estimate ET0 obtained using the FAO-56 Penman–Monteith equation. In the first part of the study, a comparison is made between the estimates provided by the neurofuzzy model and those of the following empirical models: The California Irrigation Management System, Penman, Hargreaves, and Ritchie. In this part of the study, the empirical models are calibrated using the standard FAO-56 PM ET0 values. The estimates of the neurofuzzy technique are also compared with those of the calibrated empirical models and artificial neural network (ANN) technique. Mean-squared errors, mean-absolute errors, and determination coefficient statistics are used as comparing criteria for the evaluation of the models’ performances. The comparison results reveal that the neurofuzzy models could be employed successfully in modeling the ET0 process. In the second part of the study, the potential of the neurofuzzy technique, ANN and the empirical methods in estimation ET0 using nearby station data are investigated. [ABSTRACT FROM AUTHOR]

This research was conducted to determine the king versus lateral fruit thinning effects on yield and fruit quality of 'Elstar', 'Granny Smith', 'Starkrimson Delicious', 'Ultra Red', 'Topred', and 'Jonagold' apple (Malus domestica Borkh.) cultivars grafted on MM106 rootstock in 2002-2003. Removal of the king fruit (KFR) treatment partially increased the yield in 'Jonagold', 'Elstar', and 'Granny Smith' cultivars while the effects were different by years in 'Starkrimson Delicious'. Leaving of the king fruit (KFL) treatment gave better results in the 'Topred' cultivar, and similar effects were obtained from both treatments in 'Ultra Red' cultivar. Non-significant differences were obtained from both treatments with respect to fruit weight in the 'Topred', 'Starkrimson Delicious', 'Jonagold' and 'Granny Smith' cultivars. Leaving of the king fruit treatment increased the fruit weight significantly in 'Elstar' and 'Ultra Red' cultivars in 2002. The values of fruit flesh firmness (lb), total soluble solids content (%), pH, titratable acidity (%), total and invert sugar quantity (g/100 g-1) were not found to be significantly different between the treatments with a few exceptions. The 'KFR' treatment that removed the dominant effect of the king fruit can be recommended for the 'Elstar' and 'Jonagold' cultivars because this treatment increased the yield and did not decreased the fruit weight significantly in these cultivars except for 'Elstar' in 2002. On the other hand 'KFL' treatment can be recommended for the 'Granny Smith', 'Topred' and 'Ultra Red' cultivars. Although this treatment decreased the yield of 'Granny Smith' it increased the mean fruit weight 45.6-62.7 g in the two experiment years. 'Starkrimson Delicious' did not show clear response to the treatments. [ABSTRACT FROM AUTHOR]