Reactions of TiNi with Oxygen

X-ray diffraction and metallography have been applied to study the formation conditions for the phase in Ti₄Ni₂O in the reaction of TiNi with oxygen. The phase diagram for the Ti Ni O system indicates that the phase (Fe₃W₃C structure type) is a solid solution of oxygen in Ti₂Ni. For TiNi made in an oxygen-bearing medium or from initial materials contaminated with oxygen, one gets the phase and Ni₃Ti. Those phases are formed also in surface oxidation as products from the initial interaction of the alloy with oxygen. They occur when there is a low oxygen partial pressure, as on annealing TiNi powder in a vacuum given by a rotary pump or in a layer under scale formed on a cast TiNi specimen on oxidation in air. The layer under the scale is formed because of the preferential loss of titanium from the TiNi and consists of Ti₄Ni₂O, Ni₃Ti, and an Ni(Ti) solid solution, which in turn occurs because of preferential loss of titanium from Ni₃Ti. In the subsequent oxidation stages, there is selective oxidation of Ti₄Ni₂O to lower titanium oxides. The decomposition of TiNi alloy containing oxygen when the composition is varied near the equiatomic one can be used for practical purposes. For example, the segregation of the hydride-forming phase may improve the hydrogen uptake by the alloy, while the dispersed segregation of Ni₃Ti and the lower oxides may favor hardening.     

Tunable surface roughness and wettability of a soft magnetoactive elastomer

Surface topographical modifications of a soft magnetoactive elastomer (MAE) in response to variable applied magnetic field are investigated. The analysis is performed in situ and is based on optical microscopy, spread optical reflection and optical profilometry measurements. Optical profilometry analysis shows that the responsivity of magnetic field‐induced surface roughness with respect to external magnetic field is in the range of 1 µm/T. A significant hysteresis of surface modifications takes place for increasing and decreasing fields. Investigations of shape of sessile water droplets deposited on the MAE surface reveal that field‐induced topographical modifications affect the contact angle of water at the surface. This effect is reversible and the responsivity to magnetic field is in the range of 20°/T. Despite the increased surface roughness, the apparent contact angle decreases with increasing field, which is attributed to the field‐induced protrusion of hydrophilic microparticles from the surface layer. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46221.     

Development of brannerite glass‐ceramics for the immobilization of actinide‐rich radioactive wastes

Brannerite‐based glass‐ceramics have been developed as potential waste forms for the immobilization of actinide‐rich radioactive wastes. For the first time, the formation of brannerite phases in glass has been demonstrated using uranium (U) and plutonium (Pu) with additions of gadolinium and hafnium as neutron absorbers. Both XRD and SEM‐EDS confirm that brannerite is the dominating phase with compositions close to Y_0.5U_0.5Ti₂O₆, Gd_0.2Pu_0.3U_0.5Ti₂O₆, and Gd_0.1Hf_0.1Pu_0.2U_0.6Ti₂O₆ internally crystallized in the glass. TEM SAED and Raman spectroscopy reveal the typical structure and vibration modes for brannerite. In addition, the presence of U⁵⁺ species as designed in the formulations has been confirmed by diffuse reflectance spectroscopy. More importantly, the U and Pu were partitioned exclusively in the ceramic phases with no detectable actinide in the glass.     

Coating of intravascular balloon with paclitaxel prevents constrictive remodeling of the dilated porcine femoral artery due to inhibition of intimal and media fibrosis

Here we investigated how a coating of intravascular balloon with paclitaxel (drug-coated balloon; DCB, Freeway?) impacted porcine peripheral artery vascular function and remodeling. Domestic swine (n = 54) underwent percutaneous overstretch balloon dilation of femoral and iliac arteries, controlled by angiography and optical coherence tomography (OCT). Paclitaxel tissue uptake was measured at 1 h and 1, 3, and 9 days post-dilation. At these time-points and at 32 ± 2 days, vascular function of the dilated arteries was assessed using the organ chamber model. Neointimal growth and remodeling indices were determined using OCT and histology at 32 ± 2 days. Intima and media fibrosis were quantified by picrosirius red staining. Post-inflation femoral artery tissue drug levels were 460 ± 214, 136 ± 123, 14 ± 6, and 0.1 ± 0.1 ng/mg at 1 h and 1, 3, and 9 days, respectively. Compared to plain balloon, Freeway? resulted in a significantly smaller neointimal area (P < 0.05), less tunica intima (8.0 ± 5.4 vs 14.2 ± 4.7 %) and media fibrosis (15.6 ± 7.7 vs 24.5 ± 5.4 %), and less femoral artery constrictive remodeling (remodeling index: 1.08 ± 0.08 vs 0.94 ± 0.08). The DCB was associated with significantly increased vasoconstrictor tone and endothelium-dependent vasodilation impairment shortly after post-overstretch injury. Overall, DCB dilation of peripheral arteries resulted in high drug uptake into arterial tissue. Compared with the plain balloon, the DCB was associated with decreased vessel wall fibrosis after balloon overstretch injury, and reduced degrees of constrictive remodeling and neointimal hyperplasia.     

Development of Sandwich Double-Competitive ELISA for Sulfonamides. Comparative Analytical Characteristics and Matrix Effect Resistance

Sandwich enzyme-linked immunosorbent assay (ELISA) of sulfonamides based on double-competitive interaction between haptenized protein as a captured antigen and analyte for binding to immobilized and enzyme-labeled antibodies was developed. This experimental assay format was examined in analytical properties and matrix effect resistance in comparison with usual ones: indirect, direct antigen-coated and antibody-coated ELISAs. All four assay formats were designed on the basis of interactions between the previously prepared monoclonal antibody and immunizing hapten, 4-(4-(4-aminophenylsulfonamido) phenyl)butanoic acid, providing the uniform output optical signal for correct comparison of each assay characteristic. The sensitivity (IC₅₀) of the developed competitive sandwich assay was rather below 100 ng/ml for 11 sulfonamides which was suitable for their determination in milk, muscles and animal sera at established maximum residue limit concentration. Comparative examination did not reveal changes in assay specificity, and advantages in sensitivity, matrix effect resistance, and procedure duration before commonly used assay formats. Moreover, new design of assay was shown to be three-fold more consumable in antibody reagents in comparison with direct assay formats.     

A Wavelet Packet Algorithm for Classification and Detection of Moving Vehicles

In this paper we propose a robustalgorithm that solves two related problems: 1) Classificationof acoustic signals emitted by different moving vehicles. Therecorded signals have to be assigned to pre-existing categoriesindependently from the recording surrounding conditions. 2) Detectionof the presence of a vehicle in a certain class via analysisof its acoustic signature against the existing database of recordedand processed acoustic signals. To achieve this detection withpractically no false alarms we construct the acoustic signatureof a certain vehicle using the distribution of the energies amongblocks which consist of wavelet packet coefficients. We allowno false alarms in the detection even under severe conditions;for example when the acoustic recording of target object is asuperposition of the acoustics emitted from other vehicles thatbelong to other classes. The proposed algorithm is robust evenunder severe noise and a range of rough surrounding conditions.This technology, which has many algorithmic variations, can beused to solve a wide range of classification and detection problemswhich are based on acoustic processing which are not relatedto vehicles. These have numerous applications.     

Type XX Collagen Is Elevated in Circulation of Patients with Solid Tumors

In the tumor microenvironment, the extracellular matrix (ECM) has been recognized as an important part of cancer development. The dominant ECM proteins are the 28 types of collagens, each with a unique function in tissue architecture. Type XX collagen, however, is poorly characterized, and little is known about its involvement in cancer. We developed an ELISA quantifying type XX collagen, named PRO-C20, using a monoclonal antibody raised against the C-terminus. PRO-C20 and PRO-C1, an ELISA targeting the N-terminal pro-peptide of type I collagen, was measured in sera of 219 patients with various solid cancer types and compared to sera levels of 33 healthy controls. PRO-C20 was subsequently measured in a separate cohort comprising 36 patients with pancreatic ductal adenocarcinoma (PDAC) and compared to 20 healthy controls and 11 patients with chronic pancreatitis. PRO-C20 was significantly elevated in all cancers tested: bladder, breast, colorectal, head and neck, kidney, lung, melanoma, ovarian, pancreatic, prostate, and stomach cancer (p < 0.01–p < 0.0001). PRO-C1 was only elevated in patients with ovarian cancer. PRO-C20 could discriminate between patients and healthy controls with AUROC values ranging from 0.76 to 0.92. Elevated levels were confirmed in a separate cohort of patients with PDAC (p < 0.0001). High PRO-C20 levels (above 2.57 nM) were predictive of poor survival after adjusting for the presence of metastasis, age, and sex (HR: 4.25, 95% CI: 1.52–11.9, p-value: 0.006). Circulating type XX collagen is elevated in sera of patients with various types of cancer and has prognostic value in PDAC. If validated, PRO-C20 may be a novel biomarker for patients with solid tumors and can help understand the ECM biology of cancer.     

Refractory Diborides of Zirconium and Hafnium

This paper reviews the crystal chemistry, synthesis, densification, microstructure, mechanical properties, and oxidation behavior of zirconium diboride (ZrB₂) and hafnium diboride (HfB₂) ceramics. The refractory diborides exhibit partial or complete solid solution with other transition metal diborides, which allows compositional tailoring of properties such as thermal expansion coefficient and hardness. Carbothermal reduction is the typical synthesis route, but reactive processes, solution methods, and pre-ceramic polymers can also be used. Typically, diborides are densified by hot pressing, but recently solid state and liquid phase sintering routes have been developed. Fine-grained ZrB₂ and HfB₂ have strengths of a few hundred MPa, which can increase to over 1 GPa with the addition of SiC. Pure diborides exhibit parabolic oxidation kinetics at temperatures below 1100°C, but B₂O₃ volatility leads to rapid, linear oxidation kinetics above that temperature. The addition of silica scale formers such as SiC or MoSi₂ improves the oxidation behavior above 1100°C. Based on their unique combination of properties, ZrB₂ and HfB₂ ceramics are candidates for use in the extreme environments associated with hypersonic flight, atmospheric re-entry, and rocket propulsion.     

High Doses of Pesticides Induce mtDNA Damage in Intact Mitochondria of Potato In Vitro and Do Not Impact on mtDNA Integrity of Mitochondria of Shoots and Tubers under In Vivo Exposure

It is well known that pesticides are toxic for mitochondria of animals. The effect of pesticides on plant mitochondria has not been widely studied. The goal of this research is to study the impact of metribuzin and imidacloprid on the amount of damage in the mtDNA of potato (Solanum tuberosum L.) in various conditions. We developed a set of primers to estimate mtDNA damage for the fragments in three chromosomes of potato mitogenome. We showed that both metribuzin and imidacloprid considerably damage mtDNA in vitro. Imidacloprid reduces the rate of seed germination, but does not impact the rate of the growth and number of mtDNA damage in the potato shoots. Field experiments show that pesticide exposure does not induce change in aconitate hydratase activity, and can cause a decrease in the rate of H₂O₂ production. We can assume that the mechanism of pesticide-induced mtDNA damage in vitro is not associated with H₂O₂ production, and pesticides as electrophilic substances directly interact with mtDNA. The effect of pesticides on the integrity of mtDNA in green parts of plants and in crop tubers is insignificant. In general, plant mtDNA is resistant to pesticide exposure in vivo, probably due to the presence of non-coupled respiratory systems in plant mitochondria.