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Objective: To evaluate the effectiveness and safety of salvage stereotactic ablative body radiotherapy (SABR) for recurrent renal cell carcinoma (RCC) after thermal ablation (TA). Materials and Methods: This study was a multi‐institutional retrospective analysis of patients with recurrent RCC following TA who received SABR between 2016 and 2020. The primary study outcome was freedom from local failure, evaluated radiographically based on Response Evaluation Criteria in Solid Tumours (RECIST) v1.1. Distant failure, cancer‐specific survival (CSS), overall survival (OS), treatment‐related toxicity and renal function changes following SABR were the secondary outcomes. The Kaplan–Meier method was used to estimate freedom from local and distant failure, CSS and OS. Results: Seventeen patients with 18 biopsy‐confirmed RCCs were included, with a median (interquartile range [IQR]) age at time of SABR of 75.2 (72.6–68.7) years, a median (IQR) tumour size of 3.5 (1.9–4.1) cm and follow‐up (reverse Kaplan–Meier method) of 3.36 (95% confidence interval [CI] 1.6–4.1) years. Six of the 17 patients had a solitary kidney. Five patients had failed repeat TA prior to SABR. The median (IQR) time from TA procedure to SABR was 3.03 (1.5–5.1) years. No patient experienced local progression, with a local control rate of 100%. Four patients, two with baseline metastatic disease, experienced distant progression. The distant progression‐free survival, CSS and OS at 3 years were 72.1% (95% CI 51.9%–100%), 92.3% (95% CI 78.9%–100%) and 82.1% (95% CI 62.1%–100%), respectively. The median (IQR) glomerular filtration rate before SABR was 58 (40–71) mL/min, and at last follow‐up, it was 48 (33–57) mL/min. No patient experienced grade 3+ toxicity or went on to develop end‐stage renal disease. Conclusion: The results showed that SABR appears to be an effective and safe salvage strategy in patients with recurrent RCC following TA. [ABSTRACT FROM AUTHOR]

Oxidative stress can be alleviated by antioxidants intakes. Taraxerol acetate (TA), a natural triterpenoid extracted from dandelions, may reduce the risk of metabolic disorders by regulating oxidative stress. In the study, we investigated the effects of TA in relieving oxidative stress in murine intestinal epithelial cells using multiomics techniques. Here, we found that TA activated the antioxidant defense system. Total antioxidant capacity (T-AOC) and Catalase (CAT) activity notably increased after TA treatment. Additionally, TA treatment effectively reduced the levels of lactate dehydrogenase (LDH) and malonaldehyde (MDA) and alleviated H2O2-induced oxidative stress. Furthermore, TA induced significant changes in the levels of 30 important metabolites. Specifically, it activated the complement and coagulation cascades, NF-κB and MAPK and glycerophospholipid pathways, resulting in altered transcript levels of related genes, such as Serpinb9e, SCD2, Hspa1b, and Hspa1a. Thus, the results demonstrated that TA potentially could promote health by alleviating H2O2-induced oxidative damage and provide valuable insights for its further development. [ABSTRACT FROM AUTHOR]

The formation process of the double continuous TiN/AlNb 2 protective oxide layers of TiAl-Ta alloy after high-temperature oxidation is investigated by experiment and first-principle calculation in this study. It is found that Ta promotes the formation of a double continuous protective barrier consisting of 2.5 μm TiN/0.5–1 μm Al(Nb,Ta) 2 layers during high temperature oxidation. And the lowest energy of twenty different AlNb 2 (1 ‾ 10) /TiN(110) terminations are identified by the first-principle calculation, which is significantly influenced by the distance of Nb-N bonding. Based on this, the location of Ta is studied which is preferred to be doped at Nb position of AlNb 2 for the formation of Al(Nb,Ta) 2 phase, thereby minimizing the total energy of the system. The formation of Al(Nb,Ta) 2 phase can facilitate the precipitation of a continuous TiN layer to form a strong interface with low energy. Finally, the formation mechanism of Al(Nb,Ta) 2 (1 ‾ 10) /TiN(110) is discussed in detail. The results provide new insights into the development of oxidation-resistant TiAl alloys. [ABSTRACT FROM AUTHOR]

Tiller angle (TA) is one of the most important agronomic traits that directly affects plant architecture, photosynthetic efficiency, and planting density of rice. Although many quantitative trait loci (QTLs) and associated genes for TA have been identified, the detection of TA QTLs still needs attention. This study used 238 micro-core germplasm populations for genome-wide association analysis (GWAS) of the TA. The frequency distribution of TA presented continuity in 2018 and 2019, with five QTLs designated as qTA1, qTA2, qTA6, qTA9, and qTA12. These QTLs explained phenotypic variation ranging from 5.94 to 12.38%. Among them, qTA2 and qTA6 were new QTLs of TA, and only qTA1 was detected repeatedly in 2 years. Then, 253 germplasm from the 3K Rice Genome Project were used for candidate gene and haplotypes analysis; the results showed that LOC_Os01g67770, LOC_Os02g35180, and LOC_Os09g38130 were the candidate genes of qTA1, qTA2, and qTA9, respectively. These results provided insight into the genetic improvement of plant architecture in rice. [ABSTRACT FROM AUTHOR]

Tantalum (Ta) has excellent mechanical properties, biocompatibility, and corrosion resistance. However, its application is limited by its high cost. Tantalum pentoxide (Ta2O5), a stable oxide of Ta, is a key role of Ta surface with excellent biological properties and corrosion resistance and has the advantage of a lower cost. In this study, Ta and Ta2O5 powders were pre-placed on titanium (Ti) substrates and irradiated by a diode laser to form single-layer single-pass coatings. The scanning process was performed using a range of laser powers (1000, 1500, and 2000 W) and scanning speeds (3–5, 4.5–7.5, and 6–10 mm/s). The Ta coatings showed no surface cracking. However, spherical pores were observed near the fusion line of the coating with the substrate in some samples. The porosity increased with a decreasing laser power and scanning speed. The formation of these pores was attributed mainly to the evaporation of the Ti substrate during the cladding process and the subsequent entrapment of the vapor bubbles within the coating. The Ta2O5 coatings showed almost no pores but exhibited a small number of transverse cracks on the coating surface because of the thermal expansion coefficient mismatch between the ceramic coating and the metallic substrate. For all of the coatings, the coating hardness was significantly higher than that of the substrate. The Ta2O5 coatings (580–700 HV) showed a higher hardness than the Ta coatings (350–400 HV). Moreover, the coating hardness remained approximately constant throughout the coating depth, whereas that of the Ta coatings decreased significantly with an increasing distance from the coating surface. [ABSTRACT FROM AUTHOR]

There is no authentic report from the Prophet about the meaning of the letters muqattaa, which appear at the beginning of 29 suras in the Qur'an and are recited intermittently with their names. Therefore, Islamic scholars have had two different approaches to the interpretation of these letters. According to a group of predominantly Ahl al-Hadith scholars, consisting mostly of Salaf scholars, these letters belong to the category of mutashābihāt, the meaning of which is known only to Allah, and their interpretation is not permissible. According to the second group, led by theologians, it is inappropriate to have things in the Qur'an whose meaning is unknown; therefore, these letters must have a meaning or function and it is permissible to interpret them. Many things have been said about the meaning of these letters since the early periods and these have been recorded in works on hadith, tafsir and Qur'anic sciences. In this article, the approach of Imam al-Māturīdī (d. 333/944), who is considered one of the founders of direct exegesis and the Sunnī school of theology, to the letters muqattaa in his tafsīr al-Taʾwīlātu al-Ḳurʾān is examined in comparison with previous and later tafsīrs. His attitude towards the interpretation of these letters, his approach to previous interpretations, and how he himself perceived these letters are revealed. It is seen that he simply quoted some of the views on the letters muqtaaqtaa without any commentary, which can be interpreted as his distancing himself from these interpretations. However, it is also possible to interpret his inclusion of these interpretations in his work without criticizing them as at least seeing them as possible. The commentator presents some of the opinions with some explanations that make one feel that he agrees with them. In fact, he considers all of the opinions about the hurūf al-muqattaa as probable. However, his red line in this regard is to avoid speaking definitively about them. For these are mutashābihāt, the true meaning of which can only be known by God and His Messenger. Although al-Māturīdī considers the letters muqattaa as mutashābihāt, he is not against their interpretation. However, he is against tafsir, which means a definitive judgment about them. According to his system, only the Prophet and the Companions who witnessed the revelation have the authority to interpret. Since there is no authentic news from the Prophet on this subject, scholars can only interpret them; that is, they can reveal their possible meanings. He mostly emphasizes the function of these letters in attracting the attention of the addressee and includes original interpretations of them in order to prove the prophethood of the Prophet Muhammad. There are two views in his commentary that are not found in other works. One of them is the interpretation that the exegesis of these letters is the following sentence. Māturīdī quotes this from Hasan al-Basrī. However, no similar interpretation is found in either the earlier or later sources. The fact that al-Māturīdī cites these and similar views, which were not included even by the early compilers of tafsir narrations such as Tabari and Ibn Abī Hātim, shows that his tafsir is a source that should not be neglected for rare interpretations of some verses. Māturīdī's unique interpretation of the letters Muqattaa is that these letters are alluding to the rational evidences and proofs or parables or previous books mentioned in the Qur'an to prove the prophethood of Prophet Muhammad. No such view is found in either the classical or recent works that compile commentaries on the letters Muqattaa. This is an indication of how neglected Māturīdī exegesis has been throughout history. [ABSTRACT FROM AUTHOR]

Background and Aims: The high prevalence of internet addiction (IA) has become a worldwide problem that profoundly affects people's mental health and executive function. Empirical studies have suggested trait anxiety (TA) as one of the most robust predictors of addictive behaviors. The present study investigated the neural and socio-psychological mechanisms underlying the association between TA and IA. Methods: Firstly, we tested the correlation between TA and IA. Then we investigated the longitudinal influence of TA on IA using a linear mixed effect (LME) model. Secondly, connectome-based predictive modeling (CPM) was employed to explore neuromarkers of TA, and we tested whether the identified neuromarkers of TA can predict IA. Lastly, stressful life events and default mode network (DMN) were considered as mediating variables to explore the relationship between TA and IA. Findings: A significant positive correlation between TA and IA was found and the high TA group demonstrated higher IA across time. CPM results revealed that the functional connectivity of cognitive control and emotion-regulation circuits and DMN were significantly correlated with TA. Furthermore, a significant association was found between the neuromarkers of TA and IA. Notably, the CPM results were all validated in an independent sample. The results of mediation demonstrated that stressful life events and correlated functional connectivity mediated the association between TA and IA. Conclusions: Findings of the present study facilitate a deeper understanding of the neural and socio-psychological mechanisms linking TA and IA and provide new directions for developing neural and psychological interventions. [ABSTRACT FROM AUTHOR]

This paper describes the compounds of refractory metal foils (Ti, Hf, Ta, and Ni) with ceramic layers formed as a result of combustion of reaction tapes rolled from Ti + 0.65C, Ti + 1.7B, and 5Ti + 3Si powder mixtures. Scanning electron microscopy and X-ray diffraction analysis are applied to study the microstructure, elemental composition, and phase composition of multilayer composites obtained by self-propagating high-temperature synthesis. The effect of synthesis conditions (initial temperature and applied pressure) and the initial structure of the samples on various parameters (combustion wave front propagation velocity, microstructure, phase composition, and strength properties) of the resulting layered materials is revealed. It is shown that compounds of metal foils and reaction tapes rolled from powder mixtures during combustion are ensured due to reaction diffusion, mutual impregnation, and chemical reactions occurring in the reaction tapes and on the surface of metal foils. The strength properties of the resulting materials (up to 275 MPa at 25°C and up to 72 MPa at 1100°C) are determined using a three-point loading scheme. The results of this study can contribute to the development of structural materials operating under extreme conditions. [ABSTRACT FROM AUTHOR]

Background and purpose: The distinction of tannic acid (TA) in the presence of other analogues, i.e., gallic acid (GA), dopamine (DA), glucose (Glu), and fructose (Fruc), containing vicinal diols, has long been a significant yet challenging task due to their similar chemical structures and minuscule levels. Methods: Here, the integration of 3‐aminophenyl boronic acid‐modified fluorescein isothiocyanate (3‐APBA‐FITC) for pH‐dependent ultrasensitive and selective detection of TA in wines was proposed. By performing fluorescence signal off and pH‐dependent boronate‐ester bond synthesis, the suggested probe may specifically identify TA. Results: The as‐prepared 3‐APBA‐FITC designed probe had shown ultrahigh sensitivity with a limit of detection (LOD) of 0.151 μM. Finally, in detecting TA in artificial wine with a recovery between 92.49‐93.05 % and a relative standard deviation of no more than 2.0 %, the designed strategy has been successfully applied. Conclusion: Therefore, the envisaged sensing strategy can be an interesting option for discerning detection of diols containing analytes in food products. [ABSTRACT FROM AUTHOR]

The effects of Ta content (2.72wt.%, 3.10wt.% and 4.00wt.%) on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were investigated. It is found that the content of Mo decreases with the increase of Ta in liquid phase after directional solidification, indicating the addition of Ta can reduce the element segregation in alloys. The primary and secondary dendrite arm spacings (PDAS and SDAS) of the DZ411 alloy increase with the addition of Ta, which are consistent with the models by Hunt and Wagner. The increase of PDAS and SDAS can provide enough space for the growth of tertiary dendrite arms, which hinders the growth of unfavorably oriented primary dendrites. As a result, the addition of Ta facilitates the growth of favorably oriented dendrites. More MC carbides and γ-γ' eutectics are formed in the interdendritic regions, which is attributed to the segregation of Ta in the liquid phase. Furthermore, the degree of supersaturation of W, Mo in γ matrix increases with the increase of Ta, thus, the addition of Ta promotes the formation of TCP phase. The addition of Ta also increases the microhardness in both the primary dendrite and interdendritic regions of the alloy, and the microhardness of the primary dendrite is closer to that in interdendritic regions with the increase of Ta. [ABSTRACT FROM AUTHOR]

In order to improve the oxidation resistance of the Ta substrate, a novel two-step process including molten salt electrodeposition (Na 2 WO 4 -WO 3 system) and halide activated pack cementation was adopted to prepare a WSi 2 –TaSi 2 coating on tantalum substrate. During the electrodeposition process, dense tungsten coatings were fabricated at current densities of 30 mA/cm2, 40 mA/cm2 and 50 mA/cm2. It was observed that the grain size exhibited a log-normal distribution. When the current density was 40 mA/cm2, the grain size and flattest surface of the tungsten coating reached 9.50 ± 0.23 μm and 6.792 μm, respectively. When performing the static oxidation test, the WSi 2 –TaSi 2 coating could effectively protect the Ta substrate oxidized at 1600 °C for 30 h. This is attributed to the presence of dense SiO 2 and Ta 2 O 5 , which acted as a protective layer and suppressed the further penetration of oxygen. Furthermore, due to the matching thermal expansion coefficient between each layer and the sealing ability of semi-molten SiO 2 , the four-layer SiO 2 –W 5 Si 3 –WSi 2 –Ta 5 Si 3 coating could successfully pass 721 thermal shock tests from 1600 °C to room temperature. [ABSTRACT FROM AUTHOR]

Objective To explore the effect of polymer assisted deposition of tantalum pentoxide (Ta2O5) coating on the surface of TiO2 nanotubes on the biological activity of mouse bone forming precursor cells, MC3T3-E1 cells. Methods Three sets of samples were prepared, including Ta/TiO2 nanotubes (the Ta/NT group), Ta2O5/pure titanium (the Ta2O5/PT group) and Ta2O5/ TiO2 nanotubes (the Ta2O5/NT group). The Ta2O5/PT group and the Ta2O5/NT group were prepared by polymer-assisted deposition. The three sets of samples were characterized and tested by scanning electron microscopy (SEM) to observe the surface morphology. X-ray photoelectron spectroscopy (XPS) was used to analyze surface element composition, and X-ray diffraction (XRD) was used to detect surface compounds. MC3T3-E1 cells were selected to explore the effect of three groups of samples on cell biological activity. Fluorescence microscope was used to observe the adhesion of cytoskeleton and nucleus. Cell activity was determined by CCK-8 method. Cell alkaline phosphatase (ALP) activity was detected. Calcium deposition was detected by alizarin red staining and semi-quantitative analysis. The expression levels of recombinant human bone morphogenetic protein-2 (BMP-2), ALP, osteocalcin (OCN) and osteopontin (OPN) were detected by real-time PCR. Results SEM images showed that on the surface of the Ta2O5/NT group, the TiO2 nanotube substrate was covered with a sheet-like, banded cross-linked micro-nano Ta2O5 coating structure. XRD showed that the TiO2 nanotubes in the Ta2O5/NT group presented a trace of demineralized titanium and rutile crystal structure. Compared with the Ta/NT group, the Ta2O5/NT group and the Ta2O5/PT group showed higher cell density, larger cytoskeletal mass and filamentous structure, more crosslinking and clusters, higher cytoskeletal tension and higher cell activity. The semi-quantitative analysis of alizarin red staining samples showed that calcium deposition decreased successively in the Ta2O5/NT group, the Ta/NT group and the Ta2O5/PT group (P＜0.01). The ALP activity, calcium deposition and ALP, OCN and OPN mRNA contents on day 7 and 14 were decreased successively in the Ta2O5/NT group, the Ta/NT group and the Ta2O5/PT group, and the BMP-2 mRNA content on day 14 in the Ta2O5/NT group was the highest in the three groups (P＜0.05). Conclusion Ta2O5/TiO2 nanotube composite coating can promote the adhesion of MC3T3-E1 cells, the expression of mineralization and osteogenic genes, and enhance the activities of cell and ALP, which is conducive to the play of biological activities. [ABSTRACT FROM AUTHOR]

Intumescent flame retardants (IFR) are an excellent solution to the problem of easy combustion of polymers. Still, the negative effect of the addition of flame retardants is the decline of the mechanical properties of polymers. In this context, carbon nanotubes (CNTs) are modified with tannic acid (TA) and then wrapped on the surface of ammonium polyphosphate (APP) to construct a special intumescent flame retardant structure (CTAPP). The respective advantages of the three components in the structure are explained in detail, especially the role of CNTs with high thermal conductivity in the flame retardant system. Compared with pure natural rubber (NR), the peak heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) of the composites proposed with special structural flame retardants are decreased by 68.4%, 64.3%, and 49.3%, respectively, while the limiting oxygen index (LOI) increased to 28.6%. The TA-modified CNTs wrapped on the surface of APP can effectively reduce the mechanical damage caused by the flame retardant to the polymer. To sum up, the flame retardant structure of TA-modified CNTs wrapped on APP can effectively enhance the flame retardant properties of the NR matrix and reduce the negative impact on mechanics caused by adding APP flame retardant. [ABSTRACT FROM AUTHOR]

Metal oxide clusters composed of group 5 metal ions, such as Nb and Ta, exhibit catalytic activities for CO2 fixation to styrene oxide (SO) due to the highly negative natural bonding charge of the terminal O atoms that could work as CO2 activation sites. In this study, tetrabutylammonium (TBA) salts of [TaxNb6−xO19]8− (TBA-TaxNb6−x, x = 0–6) were prepared and Ta-substitution effect on the catalytic properties of TBA-TaxNb6−x for CO2 fixation to SO was investigated. We found that TBA-Ta1Nb5 shows the highest styrene carbonate (SC) selectivity (95%) among TBA-TaxNb6−x, although the SO conversion monotonously increases with the incremental Ta substitution amount. The CO2 fixation to SO under various conditions and in situ X-ray absorption fine structure measurements reveal that CO2 is activated on both terminal O sites coordinated to the Ta (terminal OTa) and Nb (terminal ONb) sites, whereas the activation of SO proceeds on the terminal OTa and/or bridge O sites that are connected to Ta. Density functional theory (DFT) calculations reveal that the terminal OTa of TBA-Ta1Nb5 preferentially adsorbs CO2 compared with other ONb base sites. We conclude that the selective CO2 activation at terminal OTa of TBA-Ta1Nb5 without SO activation is a crucial factor for high SC selectivity in the CO2 fixation to SO. [ABSTRACT FROM AUTHOR]

TiAl alloys offer strong potential for replacing conventional nickel-base alloys in structural applications at high temperatures, which requires good high temperature performance. This study analyzes the creep performance and thermal exposure characteristics for a powder hot isostatic pressing (P-HIP) Ta-contained TiAl alloy. The microstructure characteristics, creep performance, and thermal exposure properties of the nearly lamellar (NL) alloy with a size of about 145 μm were investigated. The alloy remains 0.72 % fracture strain at room temperature after exposure at 750 ℃ for 1000 h. The fitting results of creep curves show that the creep stress index n is 15.82 at 750 ℃, indicating the power law creep mechanism. By reducing the interfacial energy, Ta can facilitate the formation of metastable structures and achieve refinement. The enrichment of Ta element at the lamellar edge, both observed after thermal exposure and creep, inhibits the growth of lamellae and hinders the expansion of cavities due to its low diffusion rate, improving the thermal stabilities and creep performance. The P-HIP Ta-contained TiAl alloy shows exciting high temperature performance. • A powder metallurgy Ti–48Al–3Nb–1.5Ta alloy with excellent high temperature performance is obtained with simple heat treatment process. • The mechanism of Ta for this alloy to improving the thermal stabilities and creep performance is revealed. The enrichment of Ta element at the lamellae edge has an effect of inhibiting the growth of lamellae and hindering the expansion of pores. • The fitting results of creep curves show that the creep stress index n is 15.82 at 750 ℃, indicating power law creep mechanism. • After exposure at 750 ℃ for 1000 h, the lamellae have no obvious coarsening and the material still has 0.72 % tensile fracture strain at room temperature, indicating favorable microstructure stability and mechanical performance. [ABSTRACT FROM AUTHOR]

The effects of Ta on the high temperature creep behavior and deformation mechanism in a Ni-based single crystal (SX) superalloy were investigated at 1120 °C/137 MPa. Ta was regarded as an essential strengthening element of the γʹ phase in the alloy, and the results indicated that the increase of Ta prolonged the creep rupture life. In this work, the addition of Ta increased the volume fraction of the γʹ phase and narrowed the γ channels, making the dislocation bowing out at the primary stage of creep more difficult. As creep continued, with a lower effective diffusion coefficient of alloying elements and larger γʹ raft thickness, the alloy with 6.5 wt% Ta addition was considered to possess the lower dislocation climbing rate, which reduced the minimum creep rate of the alloys. Subsequently, it was noted that the density of superdislocations in γʹ phase was clearly reduced with the increase of Ta. This was supposed to be the elevated Ta content in the alloy, which increased the lattice misfit and led to the formation of a denser dislocation network, thereby enhancing the interfacial strengthening effect and effectively preventing the cutting of superdislocations. The Ta effect on high-temperature creep was systematically summarized in this study, which was an important guideline for further composition design and optimization of Ni-based SX superalloys. [ABSTRACT FROM AUTHOR]

The tribological behavior of TiC/Ni composites is optimized by adding Ta, due to the improved oxidation resistance and hardness. The (Ti,Ta)C particles with core-rim structure are formed, and particle size decreases from 1.03 µm to 0.75 µm by adding 8 wt% Ta, and the hardness increases from 630.43 HV to 669.13 HV. At 20 N load, the primary wear mechanism is oxidation wear and the tribological property is influenced by oxidation resistance. At 50 N load, the main wear mechanism includes abrasive, adhesive, delamination and oxidation wear, and the tribological behavior is mainly influenced by the hardness and oxidation resistance. [ABSTRACT FROM AUTHOR]

Background: Telomerase is a cellular enzyme that prevents telomere shortening and promoting viability. The literature has reported shortened telomere length in patients with major depressive disorder (MDD).Methods: 35 patients with diagnosis of major depressive disorder (MDD) fulfilling DMS-5 criteria in the age range of 18-60 years, treatment-naïve after assessing the severity on HAM-D and HAM-A and 35 age and sex matched healthy controls were included in the study. Baseline peripheral blood monocytes (PBMC) telomerase enzyme was assessed in cases and controls and repeated in cases of MDD at 8th week after intervention with escitalopram for 8 weeks.Results: Pretreatment telomerase activity (TA) was elevated in cases as compared to controls and it was also significantly correlated to the severity of depression (p = 0.00). There was a significant positive difference in telomerase activity between non-responders (higher TA) and responders at baseline (p = 0.001) and 8th week (p = 0.012). The TA did not vary significantly amidst pretreatment and post-treatment, although it was slightly lower in the post-treatment group.Limitations: The study has few limitations in the form of small sample size, shorter duration of follow-up, and leucocyte telomeres length (LTL) was not assessed.Conclusion: The index study concludes that TA is higher in drug naïve patients with MDD than age and sex matched healthy control. The non-responders had significantly higher TA as compared to responders at baseline and post-treatment which indicates TA as a potential biomarker in the underlying biological mechanism of MDD and in response to antidepressant pharmacotherapy. [ABSTRACT FROM AUTHOR]

A strong and tough Ta/TaHfC2‐laminated composite was proposed and investigated in terms of its thermoablative behavior under plasma flame for a medium–long time (30–120 s) beyond 2517 K. In comparison to TaHfC2, the composite performed a better thermal shock resistance but an equivalent linear ablation rate (−5.40 vs. −4.08 μm/s) after ablation for 30 s. With extending the ablation time, the linear ablation rate of the composite increases. Combined with the characterization results of the ablative layer and the established volatile phase diagram at 2273 K, it was found that the composite mainly undergoes active oxidation, passive oxidation, and dissolution of oxygen during the ablation, whereas its ablative layer mainly experiences the sintering, solid solution, and loss processes of oxides. The reason the composite possesses a good ablation resistance is because the introduction of Ta‐foil‐improved toughness as well as protective effect of the ablative layer of TaHfC2. [ABSTRACT FROM AUTHOR]

Biomass carbon dots (CDs) have the characteristics of being green, nontoxic, inexpensive, and simple to prepare, and they can be used in luminescence-related fields. In this study, red, green, and blue luminescent CDs were synthesised by a simple hydrothermal method under alkaline, neutral, and acidic conditions using TA as carbon source and o-phthalaldehyde as blend. The unique optical properties of these CDs are due to the differences in their degrees of conjugation, which can be controlled by the pH value of the reaction system. These three kinds of biomass CDs have good applications in light-emitting diodes (LEDs). By mixing biomass CDs with epoxy resin, warm, and cold white LEDs with Commission Internationale de l'Elcairage (CIE) coordinates (0.35, 0.36) were successfully constructed on extremely stable multicolour CDs. This study shows that these biomass CDs are a promising material for white LED lighting. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is an inessential trace metal that accumulates in the kidney and may lead to renal toxicity by mediating oxidative stress (OS), inflammatory reactions, and apoptosis. The main objective of this experiment was to inspect the protecting potential of taxifolin (TA) on Cd-induced renal toxicity. Adult male mice were allocated into equal five groups as follows: control, TA-treated (50 mg/kg, oral), CdCl2-treated (4 mg/kg body weight (BW), p.o.), pretreated with TA (25 mg/kg) 1 h before CdCl2 injection (4 mg/kg BW, p.o.), and pretreated with TA (50 mg/kg) 1 h before CdCl2 injection (4 mg/kg BW, p.o.) for 14 days. Cd-intoxicated mice revealed higher serum urea and creatinine levels and notable histopathological alterations in the renal tissues. Malondialdehyde (MDA), nitric oxide (NO), nuclear factor-kappa B (NF-κB) p65, tumor necrosis factor-α (TNF-α), and IL-1β were increased. In contrast, glutathione levels, catalase and superoxide dismutase activities, and IL-10 levels were decreased under Cd-administered effects. Conversely, the TA pre-treatment highly protected tissues from Cd-toxicity, improved renal function, decreased MDA and NO levels, attenuated inflammation, and improved redox status in the renal tissues of Cd-intoxicated mice. The TA pre-treatment of Cd-intoxicated mice showed down-regulation of both Bax and caspase-3 protein and up-regulation of Bcl-2 protein expression in the kidney. Furthermore, TA pre-treatment induced higher upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) expression in kidney cells of Cd-intoxicated mice. Therefore, TA can protect renal tissues against Cd-induced nephrotoxicity via improving redox status, modulating inflammation, diminishing cell apoptosis, and activating the Nrf2/HO-1 signaling pathway. [ABSTRACT FROM AUTHOR]

The cephalopods in the Red Sea are active predators of animals, they capture their prey from open water. Because they are fast-swimming animals, they have some modifications in their bodies, such as a fusiform shape and fast swimming, and they transform into the water column by a special structure known as a siphon. Octopus vulgaris is one member of the Cephalopoda present in the Red Sea and has special characteristics, such as the high activity of predators for its prey, such as crustaceans and small fishes. Octopus vulgaris has a special variety of defense systems such as the ink gland, posterior salivary gland, which secretes the protein, and anterior salivary gland, which is the aim of the present study. The anterior salivary gland in Octopus vulgaris is a member of the digestive system, and has a role in protein secretion, not secreting mucus as believed until now. The anterior salivary gland in Octopus has bioactive components that are very important in pharmaceutical and biomedical applications such as anticoagulant, anesthetic, and hypotensive activities. Histochemical studies of sections of the anterior salivary gland of Octopus vulgaris show the presence of three types of secretion cells in this gland, all secreting the pure Octopoda saliva and its protein secretion. [ABSTRACT FROM AUTHOR]

The Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program, administered by the Health Resources and Service Administration in collaboration with the Administration for Children and Families, provides evidence-based home visiting services across 50 states, the District of Columbia, and five U.S. territories. MIECHV invests in comprehensive technical assistance (TA) to support and build the capacity of awardees to conduct rigorous evaluations of their programs. Throughout the course of the evaluation process, awardees received TA from the Design Options for Home Visiting Evaluation project. Between 2011 and 2020, over 173 state-led evaluations have been conducted. Individual technical assistance (TA) modalities included conference calls, emails, interactive and individualized webinars, developing and sharing resources, and involvement of content experts. When issues and challenges were identified across multiple awardees, Design Options for Home Visiting Evaluation (DOHVE) delivered targeted group TA to awardees with common needs that may benefit from peer-to-peer learning. When cross-cutting issues and challenges were identified, DOHVE used universal approaches such as webinars and guidance documents that were made available to all awardees.Through the Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program, efforts have been taken to promote awardee capacity by targeting all phases of the evaluation process, including planning, implementing, and disseminating findings and providing TA that is responsive and tailored to meet awardee-specific needs. This approach enabled DOHVE to support MIECHV awardees in expanding knowledge of their programs and the evidence base on home visiting. Lessons learned from TA provision highlight the importance of developing feasible plans and providing ongoing support during implementation. [ABSTRACT FROM AUTHOR]

During the preparation of Bi 2 Sr 2 CaCu 2 O 8+ δ (Bi2212) superconducting thin films by sol-gel method, the complexing agent and sintering conditions can significantly influence the quality and the performance of thin film. In this study, Bi2212 thin films were prepared on single crystal SrTiO 3 (001) substrate, and the phase purity, crystallinity, surface morphology and transport properties were studied particularly with different sintering temperature and time, complexing agent and its ratio to metal ions. Due to relatively low carbon content, tartaric acid (TA) as a complexing agent improved the film quality and transport properties compared with the traditional ethylenediamine tetraacetic acid (EDTA). When the complex ratios of TA to metal ions was 1:1, Bi2212 thin films exhibited good epitaxial properties, a high Bi2212 phase purity and a low surface roughness of 12.74 nm. Simultaneously, under these preparation condition, Bi2212 superconducting thin film showed a higher T c, onset of 93.28 K. [ABSTRACT FROM AUTHOR]

In a previous work, M2 high‐speed steel consisting of Ta on #45 steel was prepared by a laser metal direct forming process. After the appropriate proportion of Ta powder is added, obvious grain refinement occurs, and the amount of retained austenite decreases. Furthermore, the microhardness, impact toughness, and wear resistance increase. On the basis of this work, the microstructure and mechanical properties of the samples are further studied after tempering at different temperatures. The phase, microstructure, hardness, and wear resistance of the two kinds of steels are characterized by X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and hardness and wear tests. The results show that compared with the deposition state, the microstructure of the samples after heat treatment shows grain refinement and carbide aggregation. In addition, the hardness and impact toughness of the samples increase to different degrees after tempering at an appropriate temperature. However, after tempering, the mesh structure of the grain boundaries is destroyed, and the anchoring effect of the carbides weakens; thus, the wear rate of the samples increases to a certain extent. [ABSTRACT FROM AUTHOR]

Ta/TaHfC 2 laminated composite is suitable for various high-temperature applications. However, it still needs to be evaluated before it is used as a thermal structural material due to its unknown evolution behaviors at high temperatures. This study reports the changes in composition, microstructure, and fracture mode of Ta/TaHfC 2 laminated composite before and after annealing at 1873–2673 K. With the temperature increases, the composite's main phases change from Ta & TaHfC 2 to Ta 2 C & TaHfC 2 , Ta 4 C 3 & TaHfC 2 , and TaC & TaHfC 2 in sequence, accompanied by grain coarsening and pore increasing. The composite possesses good thermal stability below 2473 K as its retention of flexural strength is 86% after annealing at 2473 K for 10 min. • The evolution behavior of Ta/TaHfC 2 laminated composite is first reported. • The compositel's main phase change from Ta & TaHfC 2 to Ta 2 C & TaHfC 2 , Ta 4 C 3 &TaHfC 2 , and TaC & TaHfC 2 at high temperatures. • The composite possesses a high retention of flexural strength after annealing or at high temperatures. [ABSTRACT FROM AUTHOR]

A giant deposit of loparite ores, a source of Nb, Ta, and rare earth metals, is related to the world's largest layered Lovozero pluton in the Kola Peninsula. The Sr and U contents and Nb/Ta ratio increase and the REE and Ba contents decrease in loparite in the vertical section of the Lovozero deposit to a depth of 2450 m. Detailed studies have shown that the change in the morphology of loparite and in the time of its crystallization is a new geochemical indicator of the ore potential of alkaline magmas for rare metals (loparite ores). The ore-bearing zones with rare metals of the Lovozero intrusion are only those that contain euhedral (cumulative) loparite. The lowermost zone of the intrusion (70 m from the lower contact), which is characterized by anhedral loparite, is not promising for rare metals. Thus, early cotectic saturation of the melt in the ore mineral is a necessary condition for the formation of magmatic rare metal deposits. In this case, the ore minerals have a euhedral morphology. If the content of the ore component is significantly below cotectic, the crystallization of the ore mineral would occur at late stages of the formation of rocks in a small volume of the interstitial melt, when the events of differentiation of convective gravitation and segregation of the mineral phases are difficult, leading to the dispersion of ore components as anhedral grains of accessory minerals. [ABSTRACT FROM AUTHOR]

Two kinds of Ta/HfC composites with laminated structure were fabricated by spark plasma sintering of a green body with alternately stacked HfC powder and Ta fibre net or foil layers. The composition, microstructure, and physical/mechanical properties of the Ta/HfC composites were investigated by XRD, SEM, EDS, and other techniques. The results revealed that cubic Ta and HfC were the main phases in the Ta/HfC composites, despite their partial reaction to form δ -TaC 1-x (0 < x < 0.22), HfC 1-y (0 < y < 0.4), and β -Ta 2 C at the interface. The introduction of continuous Ta as the interlayers limited densification but improved the mechanical properties of HfC ceramics. Compared to Ta fibre net, Ta foil showed a better toughening effect; in particular, the flexural strength, fracture toughness, and rupture work of the Ta foil /HfC composites were 290 ± 29 MPa, 5.53 ± 1.59 MPa m1/2, and 900 J/m2, which were approximately 218%, 148%, and 543% higher than those of HfC, respectively. [ABSTRACT FROM AUTHOR]

Highlights: Phase-change memory based on Ta-doped antimony telluride (Sb2Te) exhibits both high-speed characteristics and excellent high-temperature characteristics, allowing improved performance and new applications. The high coordination number of Ta and the strong bonds between Ta and Sb/Te atoms enhance the robustness of the amorphous structure, ensuring good thermal stability. Through the three-dimensional limit, the formation of small grains reduces the power consumption and improves the long-term endurance.Phase-change memory (PCM) has considerable promise for new applications based on von Neumann and emerging neuromorphic computing systems. However, a key challenge in harnessing the advantages of PCM devices is achieving high-speed operation of these devices at elevated temperatures, which is critical for the efficient processing and reliable storage of data at full capacity. Herein, we report a novel PCM device based on Ta-doped antimony telluride (Sb2Te), which exhibits both high-speed characteristics and excellent high-temperature characteristics, with an operation speed of 2 ns, endurance of > 106 cycles, and reversible switching at 140 °C. The high coordination number of Ta and the strong bonds between Ta and Sb/Te atoms contribute to the robustness of the amorphous structure, which improves the thermal stability. Furthermore, the small grains in the three-dimensional limit lead to an increased energy efficiency and a reduced risk of layer segregation, reducing the power consumption and improving the long-term endurance. Our findings for this new Ta–Sb2Te material system can facilitate the development of PCMs with improved performance and novel applications. [ABSTRACT FROM AUTHOR]

The results of the formation of an original material based on thin films of metal nanoclusters and the investigation of its chemical composition, surface morphology, and structure are presented. Monodisperse thin films comprised of individual nanoclusters of Ta, Mo, and Ni metals were manufactured by gas-phase magnetron sputtering. Images of the surface were obtained by scanning electron microscopy and it was shown that the Ta and Mo films had a well-developed porous structure and consisted of separate nanoclusters contacting each other only at the interface. The chemical composition of the resulting films immediately after deposition (in situ) and after exposure to the atmosphere (ex situ) was investigated by X-ray photoelectron spectroscopy. It was shown that the exposure to the atmosphere led to the oxidation of the obtained films, namely, to the formation of oxide shells in nanoclusters that formed the films. The possibility of creating thin-film photodetectors based on nanocluster films to detect the decay of isomeric nuclear transition in 229Th nuclei is discussed. [ABSTRACT FROM AUTHOR]

Additional excitation functions for deuteron induced reactions up to 48.6 MeV on quasi mono-isotopic Ta (99.99% 181Ta) were experimentally determined using the activation method through stacked foil irradiation. Cross-sections for the production of 177,178,181W, 177cum, 178g,180g, 182m+gTa and 175,179m2,180m,181Hf were derived from high resolution gamma-spectrometry and X-ray analysis. Comparison with the few earlier published experimental data and with values predicted by the theoretical code TALYS 1.6 (as available in the on-line library TENDL-2019) are discussed. Thick target yields for medically or industrially relevant longer-lived 177,178g,180g,182m+gTa and 178,181W, calculated from fits to our experimental excitation curves, are discussed. Estimations on possible occupational doses to maintenance or scientific personnel around high power accelerators originating from activated Ta structural elements are updated. [ABSTRACT FROM AUTHOR]

The effects of Zr, Mo and Zr, Ta powder mixtures during spark-plasma sintering of compositions at pressing loading of 60 MPa in the range 1200 – 1600°C on the phase composition, microstructure, grain sizes of crystalline phases, relative density, linear shrinkage, physical-mechanical properties, and linear correlation of elasticity modulus and fracture toughness of mullite–β-SiAlON–c-BN samples are shown in the present work. Synthesized powders of β-SiAlON and c-BN are characterized by extensive crystallization of β-SiAlON and c-BN, respectively. Sintered samples with Zr, Mo and Zr, Ta mixtures show extensive mullite formation, active growth of β-SiAlON, and less extensive growth of c-BN in the range 1200 – 1600°C. Active growth of crystalline β-Mo, Zr, Mo, and Mo2Zr phases is noticeable in the sample with Zr, Mo mixtures but extensive growth of crystalline β-Ta, Zr, α-Zr, Ta, β-Ta, Ta3Zr, and Ta3Zr2 is observed in the sample with Zr, Ta mixtures with an increase of temperature. The Zr, Mo mixture favors the formation of a more uniformly and densely sintered microstructure of the ceramic phase, round metallic Mo and β-Mo, Zr particles, more reinforced ceramic-metallic boundary areas, and metallic phases and facilitates the reduction of crystalline-phase grain sizes in the range 1400 – 1600°C. As a result, the composition with a Zr, Mo mixture sinters more uniformly and gradually. The corresponding sample shows larger values of physical-mechanical properties, higher cracking resistance with an insignificant quantity of microcracks, and a larger linear correlation of the elasticity modulus and fracture toughness in the range 1200 – 1600°C. [ABSTRACT FROM AUTHOR]

Graduate students who serve as teaching assistants are a critical part of STEM (science, technology, engineering, mathematics) education and research at large universities in the U.S. Yet just like faculty, graduate students are not immune to the publish or perish paradigm, which can compete with one's dedication to teaching. While in recent years many STEM faculty members have become aware of how well undergraduates can assist instructors in their teaching, many, if not most, university faculty still teach in traditional settings, where graduate students are the norm and use of undergraduates is a completely unexploited opportunity. Undergraduates can serve as effective teaching assistants and may bring unique skills and experience to undergraduate instruction not held by graduate students. Undergraduate teaching assistants (UTAs) can provide additional support for reformed practices, which raise student learning. Based on cost, prior experience and success as students in same course, and shared vision with professors, a number of institutions have initiated UTA programs and reported increased student learning. The audience of this paper is faculty who are not familiar with the use of UTAs in university teaching, and the purpose is to review the literature on UTAs, contrast the contributions of UTAs and graduate teaching assistants, and examine the potential value of UTAs in undergraduate education. [ABSTRACT FROM AUTHOR]

NiAlTa alloys were prepared to improve oxidation and hot corrosion resistance of single crystal blade tips as well as the sealing performance of an engine. The oxidation and hot corrosion behaviors of NiAlTa alloys were investigated. The results showed that NiAlTa alloys exhibited low oxidative degradation rates at 1000–1100 ℃. τ 1 -NiTaAl and β-NiAl phases exhibited different oxidation behaviors. NiAlTa alloys were more resistant to attack by mixed salts than pure salts. NiTaAl phase accelerated the alloy failure by acting as a fast diffusion channel for corrosive media. The oxidation mechanisms, hot corrosion mechanisms, and the effects of Ta were discussed. • NiAlTa alloys exhibited low oxidative degradation rates at 1000–1100 ℃. • NiAlTa alloys were more resistant to attack by mixed salts than pure salts. • The oxidation, hot corrosion mechanisms, and the effects of Ta were discussed. • The NiAl and NiTaAl phases showed different oxidation and hot corrosion behaviors. • Ta hinder the mass transfer of O in Al 2 O 3 by reducing the concentration of oxygen vacancies. Nanoscale Ni x Ta y particles act as a diffusion barrier for Al or O. [ABSTRACT FROM AUTHOR]

The development of refractory status epilepticus (SE) following sarin intoxication presents a therapeutic challenge. Here, we evaluated the efficacy of delayed combined double or triple treatment in reducing abnormal epileptiform seizure activity (ESA) and the ensuing long-term neuronal insult. SE was induced in rats by exposure to 1.2 LD 50 sarin followed by treatment with atropine and TMB4 (TA) 1 min later. Double treatment with ketamine and midazolam or triple treatment with ketamine, midazolam and levetiracetam was administered 30 min post-exposure, and the results were compared to those of single treatment with midazolam alone or triple treatment with ketamine, midazolam, and valproate, which was previously shown to ameliorate this neurological insult. Toxicity and electrocorticogram activity were monitored during the first week, and behavioral evaluations were performed 2 weeks post-exposure, followed by biochemical and immunohistopathological analyses. Both double and triple treatment reduced mortality and enhanced weight recovery compared to TA-only treatment. Triple treatment and, to a lesser extent, double treatment significantly ameliorated the ESA duration. Compared to the TA-only or the TA+ midazolam treatment, both double and triple treatment reduced the sarin-induced increase in the neuroinflammatory marker PGE 2 and the brain damage marker TSPO and decreased gliosis, astrocytosis and neuronal damage. Finally, both double and triple treatment prevented a change in behavior, as measured in the open field test. No significant difference was observed between the efficacies of the two triple treatments, and both triple combinations completely prevented brain injury (no differences from the naïve rats). Delayed double and, to a greater extent, triple treatment may serve as an efficacious delayed therapy, preventing brain insult propagation following sarin-induced refractory SE. • Exposure to the nerve agent sarin induces prolonged refractory seizures. • Late benzodiazepine treatment is insufficient in mitigating seizures. • Dual therapy of midazolam & ketamine attenuates seizures. • Triple therapy of midazolam, ketamine & levetiracetam or valproate rapidly suppresses seizures. • Dual & triple therapy prevent the biochemical and histopathological neurotoxicity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Mixed acid open acid dissolution and alkali fusion methods are the two main dissolution methods for determination of rare earth and refractory elements in geological samples by inductively coupled plasma-mass spectrometry (ICP-MS). However, the composition of geological samples is complex. For special elements and special samples, the traditional acid-dissolving method will cause incomplete digestion of some elements, which makes the measurement results inaccurate. The operation process of the alkali fusion method is cumbersome. The solution has high salinity, which can easily cause matrix interference and block the sample introduction system. OBJECTIVES: To improve the traditional four-acid and penta-acid systems in the determination of rare earth elements. METHODS: The hydrofluoric acid-nitric acid-sulfuric acid open acid solution system was used to determine the 15 rare earth elements by using the national standard material to prepare a standard curve. At the same time, the lithium metaborate alkali fusion method was improved. The sample was extracted with lithium metaborate alkali, and the solution was added to the alkaline condition by adding sodium hydroxide. The measured element was coprecipitated with lithium metaborate, and the flux was separated and filtered, and then reconstituted with nitric acid. Nineteen elements such as rare earth and lanthanum zirconium were measured. RESULTS: The relative deviations between the measured value and the certified value of the two dissolution methods were 1.09%-9.30%. The results of determination of Nb, Ta, Zr and Hf by mixed acid open dissolution method and rare earth element by lithium metaborate alkali fusion method were compared with those of another laboratory that used closed acid dissolution methods. The relative deviations between the two groups were 0.13%-15.32%. CONCLUSIONS: The mixed acid open dissolution method is suitable for the determination of rare earth elements in geological samples, whereas the lithium metaborate alkali fusion method is not only suitable for the determination of rare earth elements and Nb, Ta, Zr and Hf in geological samples, but also for the determination of Nb, Ta, Zr and Hf in ancient high pressure metamorphic rock samples and the sample with a high Al content. [ABSTRACT FROM AUTHOR]

Microwave-assisted formulation is becoming an established method of formulation in industry, providing a fast, economic and environmentally more favourable way to create products, such as those manufactured in the pharmaceutical industry. However, the effect of microwave-induced heating on a compound, or mixture of compounds, is yet to be fully explored, possibly indicating that this method of formulation may not be suitable in all cases. In this study, the effect of microwave heating was investigated through the application of microwave thermal analysis to six model pharmaceutical compounds and a set of four model excipients. Benzocaine, haloperidol, ibuprofen, indomethacin, ketoprofen and phenylbutazone were analysed, along with four excipients, namely β-cyclodextrin, d-mannitol, stearic acid and Syloid® XDP 3050 silica using microwave thermal analysis. Samples were heated by microwave irradiation at 5 °C min−1 to a minimum of 160 °C, held isothermally and then slowly cooled to room temperature. Thermal profiles were analysed and compared with data obtained using differential scanning calorimetry (DSC) and hot-stage microscopy (HSM). Overall, it was found that the process of microwave heating produced different thermal profiles to those seen using traditional, conductive heating. Investigating differences in thermal profiles can be a useful way to consider the effect of microwave-induced heating on formulations which can, in turn, help guide formulation choices. [ABSTRACT FROM AUTHOR]

We analyze the switching and retention properties of 65-nm integrated Cu(−Ge-Te)/(Ta)/GeSe conductive bridge random access memory devices operated at 50~μA. We evidence the crucial role played by a Ta buffer layer inserted between the Cu alloy and GeSe layers in decreasing the preforming current and in significantly improving the low-resistance state retention. Cu alloys of different compositions are tested to reveal lower device variability and longer retention with Cu2GeTe3 active electrode. [ABSTRACT FROM AUTHOR]

The corrosion behavior of pure Ta and laser surface melting–treated Ta sheets was investigated in an equimolar NaCl–KCl melt at 850°C in air. The results show that the predominant factors involved in the consumption of materials were reactions that form sodium‐containing oxides and Ta2O5. High corrosion stress led to slip of the untreated Ta surface grains, further resulting in preferential corrosion along slip bands. The slip of surface grains substantially deteriorated the bonding between the corrosion scale and matrix, thus leading to rapid degradation of the corrosion scale. The melt layer consisted of a thin Ta2O5 film, and the inner dendrite layer demonstrated self‐healing characteristics during corrosion and presented a better hot corrosion resistance than the untreated Ta owing to the excellent bonding at the scale and melt layer interface. [ABSTRACT FROM AUTHOR]

Multi-stage Spark Plasma Sintering (MS-SPS) of ZrB 2 -20 vol% SiC-10 vol% Si 3 N 4 (ZSS) and ZrB 2 -20 vol% SiC-10 wt% Ta (ZST) composites were carried out at 1900 °C for 3 min to densify the ZrB 2 -based composites. The microstructure of ZSS composite consisted of new secondary phases (ZrO 2 , BN, ZrN) along with SiC and ZrB 2. Interestingly, ZST sample exhibited core-shell/rim structure and it comprised of ZrB 2 core, (Zr,Ta)B 2 rim, SiC, ZrO 2 and (Zr,Ta)C phases. The presence of new phases and annihilation of Si 3 N 4 or Ta additive in both the sintered samples was clear indication of involvement of sintering reactions. The SEM of cross sectional samples revealed presence of three distinctive layers for the ZrB 2 samples after the isothermal oxidation at 1600 °C for 10 h. In particular, no SiC depleted layer was observed for ZSS and its presence was evident in ZST composite. The weight gain (varied between 15.25 and 16.66 mg/cm2) of the ZrB 2 composites was comparable and significant difference in the oxide layer thickness (changed from 255 to 476 μm) was noticed. Overall the ZST sample offers better oxidation resistance in view of protective nature of its oxide layer. • Highly dense (> 98%) ZrB 2 materials were pressed via MS-SPS. • New secondary phases were observed in ZrB 2 -20vol.% SiC-10vol.% Si 3 N 4. • ZrB 2 -20vol.% SiC-10wt.% Ta exhibited core-rim microstructure. • The ZrB 2 -20vol.% SiC-10wt.% Ta exhibited better oxidation resistance. [ABSTRACT FROM AUTHOR]

As one of the most important indicators of nonlinear time series, temporal asymmetric (TA) or temporal irreversible behaviors of daily fluctuations from four temperature variables, including mean temperature (Tmean), maximum temperature (Tmax), minimum temperature (Tmin) and diurnal temperature range (DTR, DTR = Tmax − Tmin), have been quantified through both observations and reanalysis over China by two TA measures. One is L2 from directed horizontal visibility graph and the other is L1 from consecutive increasing and decreasing steps. The results show that there are differential TA features among daily temperature fluctuations. Firstly, there are marked differences in TA strengths among different temperature variables. It is found that dominated uniformly significant TA (larger than the threshold from corresponding surrogates) emerges in almost all observed Tmean fluctuations. However, this kind of uniformly significant TA can't be found in Tmax, Tmin and DTR for both observed and reanalysis data sets. Since both TA measures L1 and L2 quantify the temporal structures in the given series, this distinguishable TA strengths found in different temperature variables indicates that there are distinct temporal structures in the different temperature variables' variations. Secondly, the TA in each temperature variable is region dependent. The TA strength for each temperature variable is spatially non-uniform with some strong and weak TA regional patterns and these strong and weak TA regional patterns may depend on local weather or climate conditions. Moreover, comparison studies of the same temperature variable reveal that time irreversible features are distinguishable between observations and reanalysis, and this differential feature can be taken as an index to evaluate the quality of reanalysis. [ABSTRACT FROM AUTHOR]

The paper is aimed at informing on Netzsch STA 409 CD/3/403/5/G apparatus, a specially-adapted type of the commercial STA 409 CD - QMS 403/5 Skimmer Coupling Instrument combining methods of thermal analysis with Knudsen effusion mass spectrometry. Construction parameters as well as advantages and disadvantages of the instrument are presented. The instrument can be used for a broad spectrum of studies in materials field from which some of them, including e.g. thermodynamic and phase transformations studies, study of surface and catalytic processes, investigation of materials on multiscale level, are demonstrated. The new multifunction design as well as the instrument capabilities are discussed with respect to already published information. fx1 • Specially-adapted Netzsch STA Skimmer Coupling Instrument for TA - KEMS is presented. • A few examples of recent thermodynamic and phase transformations studies are given. • Results of TA and vapour pressure measurements of pure Cd and Yb are summarized. • Study of surface and catalytic properties of AgCu alloy nanoparticles is shown. • Advantages and disadvantages of the multifunction instrumental design are discussed. [ABSTRACT FROM AUTHOR]

In-situ TiC/Ni composite with Ta element was fabricated by reactive sintering. Ta element solid solubilizes in TiC particles and Ni matrix. The addition of Ta reduces the oxidation rate of TiC at initial stage of oxidation, and suppresses the outward diffusion of Ti atom and inward diffusion of O atom after the formation of oxide scale, leading to the decrease of TiO 2 and NiTiO 3 content in oxide scale. The oxidation resistance of composites is optimized. Ta element improves the electrical conductivity of composites at 800 °C by increasing electron concentration in oxide scale and reducing the thickness of oxide scale. • In-situ TiC/Ni composite with Ta element was fabricated by reactive sintering. • Ta element solid solubilizes in TiC particles and Ni matrix. • Ta reduces the oxidation rate of TiC at initial stage of oxidation. • Ta suppresses the outward diffusion of Ti atom and inward diffusion of O atom. • Ta optimizes the oxidation resistance and electrical conductivity of composites. [ABSTRACT FROM AUTHOR]

Abstract In order to improve mechanical properties, different Ta contents were added into Ti42Al6Nb2.6C alloys, which were prepared by vacuum arc melting. Microstructure evolution and mechanical properties of the alloys were experimentally and theoretically studied, especially the B2 phase disappearing mechanism. Results show that the B2 phase is disappeared when Ta content is more than 0.2at.%. With increasing Ta content, the length-width ratio of Ti 2 AlC decreases, but the lamellar colony size increases, even up to 2.2 times. EDS results show that Ta distributes uniformly. Owe to its higher melting point and bigger atom radius, Ta has lower diffusion rate and impedes diffusion of Nb during solidification, which results in disappearance of B2 phase. Because Ta can expand solid-liquid temperature range, and this provides more time for grain growing, which accounts for the increasing lamellar colony size. Compressive testing shows that the strength increases 1.2 times and the strain increases 3.2 times when Ta content is 0.2 at.%. Tensile strength at 750 °C is improved by adding Ta. These improvements are mainly resulted from the solid-solution strengthening of Ta and Nb, and the elimination of B2 phase, although the lamellar colony size is increased. Highlights • The B2 phase is eliminated when Ta (≥0.2at.%) is added in high-Nb TiAl alloys. • The lattice parameter of γ phase increases with increasing of Ta content. • The length-width ratio of Ti 2 AlC decreases with increasing of Ta content. • Ta is beneficial for the solid-solution and distribution uniformly of Nb element. • Mechanical properties improve with adding Ta at room and elevated temperature. [ABSTRACT FROM AUTHOR]

Highlights • Cumulative frequency distributions suggest E side would produce softer fruit. • E side of the plant produced more blue fruit at harvest and more total fruit production. • Six days of harvest delay increased the amount of soft and very soft fruit. Abstract For blueberry, harvest readiness is based on skin color, with fruit being considered ready to pick when the berry skin reaches 100% blue coverage. The extended bloom period for the blueberry inflorescence and uneven developmental rates can yield fully blue fruit that are widely different in physiological maturity, at any given harvest date. The objective of this study was to determine the inherent variability in the firmness of a synchronized cohort of blueberry fruit and the effects of harvest delay and position within the canopy on fruit characteristics at harvest and after refrigerated storage. During two consecutive seasons, the harvest canopy of ‘Duke’ and ‘Brigitta’ was divided into two regions as east (E) and west (W) sides. Fruit of a specific developmental stage from each side were either harvested when reaching 100% blue coverage (ripe fruit: B100) or allowed to stay on the plant for six additional days (over-ripe fruit: B100+6). Despite the narrow period of time elapsed between harvests of ripe and over-ripe fruit, variation in firmness was extensive, with decreases up to 24%, depending on year and cultivar. The six days of additional development were enough to increase the amount of soft and very soft fruit at harvest and after storage, demonstrating the importance of frequent harvests to improve firmness at final destinations. Both the percentage of blue fruit at each harvest date and total fruit produced were higher on the E side of the plant. Year-to-year variation in firmness exceeded that caused by the imposed treatment, which highlights the need to understand the environmental factors contributing to fruit softening. This is the first report on in-plant fruit variability for blueberry and its effect on postharvest performance. [ABSTRACT FROM AUTHOR]

North Eastern Anatolia had a significant contribution to development of cultivated apple. A lot of local apple genotypes have been successfully grown without any pesticide applications despite to high rainfall (900–2300 mm) and humidity (70–85%) especially at the coastal part of the Eastern Black Sea Region of North Eastern Anatolia. We have investigated and selected local apple genotypes from the region which could be of importance for apple breeding by fruit attributes. In this study, sensory characteristics (186 accessions) and quantitative characteristics (176 accessions) determined based on Apple Descriptor, and were analyzed by Multidimensional Scaling analysis. Harvest maturity dates classified the genotypes into early season (19), mid-season (13) and late season (154) apples. Among the genotypes, 39.25% had medium-sized fruits, 53.23% had intermediate attractiveness, 50% had ground color of green-yellow, 59.68% had skin over color of red, 61.29% had good eating quality and 53.76% had fine flesh texture. Quantitative characters showed large variation that fruit weight ranged from 27.4 g to 246.4 g, SSC from 8.6% to 15.4%, TA from 0.08% to 2.24%. Multidimensional Scaling analysis indicated that the genotypes harvested in early and mid-season exhibited larger variation for sensory and quantitative characteristics than did late season apples. Although several genotypes were differentiated for investigated characteristics and/or variables in early and late season groups, mid-season apples did not tend to form any cluster. [ABSTRACT FROM AUTHOR]

Abstract Excellent oxidation resistance is one crucial requirement for intermediate-temperature solid oxide fuel cell interconnects. Composites with proper coefficient of thermal expansion and good electrical conductivity have been proposed as promising intermediate-temperature solid oxide fuel cell interconnects, whereas the oxidation resistance of them is still need to be improved. In the paper, the TiC/hastelloy composites with minor Ta element are prepared by in-situ reactive infiltration method, and the mass gain decreases from 1.18 mg cm−2 to 0.48 mg cm−2 (800 °C/100 h) by adding minor Ta, which is the lowest among existing composite interconnects. The oxide scale composed of Ni/Ti/Cr oxides with sandwich structure is formed on the composites. Compared with TiC/hastelloy composites without Ta element, Ta effectively prevents the inward diffusion of oxygen during oxidation by reducing oxygen vacancy concentration in TiO 2 layer, and the inner oxide layer (O diffusion layer) vanishes, leading to the oxidation resistance optimization of composites. Meanwhile, the composites with Ta show linear suitable thermal expansion, 11.6 × 10−6 °C−1, and high electrical conductivity, 5500 S cm−1. Therefore, the addition of minor Ta element is one effective method to optimize the oxidation resistance of TiC/hastelloy composites. Highlights • TiC/hastelloy composites with Ta were prepared by in-situ reactive infiltration. • Lowest oxidation mass gain in composites interconnect is attained by adding Ta. • The replacement of Ti4+ by Ta5+ in TiO 2 lowers O vacancy concentration. • Oxidation resistance was improved by restricting inward diffusion of O. • Composite with Ta has proper CTE (11.6 × 10−6oC−1) and high electrical conductivity. [ABSTRACT FROM AUTHOR]

A voltammetric method for the determination of the high field‐strength elements Ti, Zr, Hf, Nb and Ta by adsorptive stripping of their tartrate complexes is presented. The applicability of the method to geological and metallurgical samples is illustrated by the analysis of certified reference materials (USGS BCR‐2 basalt, BCS‐CRM 388 zircon and Euronorm CRM 579‐1 ferroniobium). Suitable sample preparation techniques, involving fusion with LiBO2 and acidic and basic fluxes, followed by preliminary separation by anion chromatography are described. The method is rapid, affordable and environmentally friendly as it does not require problematic compounds such as hydrofluoric acid or toxic solvents and represents an alternative to more commonly used methods (AAS, ICP‐OES, ICP‐MS). [ABSTRACT FROM AUTHOR]

Aiming at the micro-structures of rapid solidified Ta system under cooling rate of 1 × 1010 K/s, the lowest-energy and meta-stable geometric structure of Ta n (n = 19–30) clusters are systematically investigated via MD simulation, DFT calculation and CALYPSO search. It is revealed that the ground-state geometric structure of free Ta clusters plays a significant role in determining its solidified atomic structures and evolution laws in the early stage of nucleation. We explained why the hexagonal close packed (hcp) atomic clusters (Ta 22) dominate the solid state of Ta when cooled at a rate of 1 × 1010 K/s. And found that the coexistence of slightly distorted icosahedral (Ta 13) and hcp clusters (Ta 22) at 300 K is due to the high energy stability of free Ta 26 –C 2v (B) cluster. The larger size of Ta clusters with a perfect closed-shell geometric structure plays a key role in energetic effects, as demonstrated by their thermodynamic stability in terms of binding energy. Additionally, electronic structure stability is achieved when there are fewer electrons on the Fermi level (N(E F)), resulting in Ta atomic clusters that exhibit higher energetic stability and lower chemical activity. Our analysis of the interaction between different atoms in Ta clusters revealed that stronger electronic interactions of central(c)-central(c) and central(c)-shell(s) atoms contribute to the higher energy and chemical stability. Finally, we provide insights into understanding the growth patterns of nucleation in liquid metals through an examination of geometric and electronic structures of free Ta cluster. • New growth pattern in rapid solidified Ta metal was discovered. • Ground-state clusters determining its solidified atomic structures in nucleation. • We explained why the hcp and distorted icosahedral clusters dominate in Ta solid. • The work provides a clear direction for future experimental studies. [ABSTRACT FROM AUTHOR]

Grape cv. Askari is one of the dominant cultivars of the city of Dena, which is affected by freezing temperatures of the winter every year. In order to study the primary bud necrosis and fruit set of the following year, the present research was carried out in one of the vineyards of Dena County in a twofactor factorial experiment based on a completely randomized block design with three replications and two vines per plot. In this experiment, salicylic acid (0, 150, 300 and 450 mg/l) and potassium sulfate (0, 1 and 2%) were used as spraying in one phase. Bud sampling was performed in three stages, and the primary bud necrosis percentage was recorded in each stage. Salicylic acid at 300 mg/l and interaction of 450 mg/l salicylic acid and 2% potassium sulfate had the highest effect on the reduction of primary bud necrosis of grape at 5% level, and the rest of the treatments did not have any significant effect on the primary bud necrosis percentage. The lowest mortality percentage of primary buds was observed in the second stage of sampling at 5% level. The results of variance analysis showed that the interaction of salicylic acid and potassium sulfate at 5% level had a significant effect on fruit diameter, and the remaining treatments showed no significant effect on the trait. Means comparison of fruit diameter showed that the interaction of salicylic acid at 150 mg/l and 2% potassium sulfate had the highest effect on the diameter of berry, and increasing the percentage of potassium sulfate increased the diameter of berry. Salicylic acid and potassium sulfate treatments had no significant effect on average length, berry weight, pH, TA, TSS and percentage of berry set. [ABSTRACT FROM AUTHOR]