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Two field experiments were carried out during the two consecutive summer seasons of 2019 and 2020 at Experimental Farm (Ghazala Farm) of Agric. Fac., Zagazig Univ., Egypt. This study was to try to enhance the growth and yield of guar plant. The experiment was set up as split-plot design between NPK fertilization as main plot and bio-fertilization as sub-plot. The NPK fertilization levels were (0.0, 75, 100 and 125% of recommended level), while, the Bradyrhizobium inoculation rates were (0.0, 200 and 400 g/feddan). The NPK fertilization recommended rate (RR) was Ammonium sulfate (20.5% N) at 200 kg/feddan, calcium super phosphate (15.5% P2O5) at 200 kg/feddan and potassium sulfate (48% K2O) at 100 kg/feddan. The obtained results revealed that fertilized guar plants with 125% RR significantly increased plant growth (plant height, number of leaves and branches/ plant, fresh and dry weights of branches, leaves and roots/plant and root length), yield components (pods number per plant and seed yield per plant and per feddan) as well as total carbohydrates content compared to control and the other levels under study. Moreover, the highest Bradyrhizobium inoculation rate (400 g/feddan) significantly recorded the highest values of all abovementioned parameters compared to control and lowest one. Predominantly, the results of this study showed that fertilized guar plants with 125% RR of NPK fertilization could help to enhance growth and productivity of guar (Cyamopsis tetragolnoloba Taub.) plant combined with 400 g/feddan of Bradyrhizobium inoculation rate under Sharkia Governorate conditions. [ABSTRACT FROM AUTHOR]

Magnesia‐rich spinel (M2A)‐reinforced yttria‐stabilized zirconia (YSZ) ceramic composites have been fabricated by SPS using m‐ZrO2, Y2O3, and waste‐derived M2A powders. The results showed that m‐ZrO2 in M2A‐free YSZ0 specimen is partially stabilized upon temperature rising into tetragonal phase whereas YSZ10‐50 composites containing 10‐50 wt% M2A demonstrated variant behavior where their m‐ZrO2 is stabilized into a cubic form. YSZ10‐50 composites SPSed at 1400°C for 30 minutes revealed greater than 99% relative density, 10‐13 GPa Vickers hardness, 3.5‐5 MPa m0.5 fracture toughness and less than 0.5% apparent porosity. Aging hydration test for five hours soaking at 134°C and water vapor pressure of 2 bar, resulted in a conversion of ~2.8% of t‐ZrO2 to m‐ZrO2 for M2A‐free YSZ0 composite but it does not affect the YSZ10‐50 composites. The outcomes indicate that M2A has significantly improved both the densification and stabilization behavior of m‐ZrO2 through facilitating the diffusion of Y3+, Mg2+, and Al3+ ions inside zirconia lattice structure. In this regard, this study opens the door wide for producing fully stabilized c‐ZrO2 ceramics that could be potentially utilized as industrial ceramics for a broad scope of structural applications of high temperature, high‐stress and corrosive environmental conditions. [ABSTRACT FROM AUTHOR]

Cubic‐stabilized zirconia ceramic composites have been synthesized by conventional sintering, starting from commercial m‐ZrO2, Y2O3, and waste‐derived magnesium aluminate spinel (MA) powders. In this work, the effect of sintering temperature and MA content on stabilization and densification properties of YSZ have been duly considered. MA‐free YSZ0 composite sintered at 1600°C‐1700°C revealed m‐ and t‐ZrO2 dual‐phase structure where its m‐ZrO2 was partially stabilized upon temperature rising into tetragonal phase by Y3+ diffusion inside zirconia structure. YSZ10‐50 composites containing 10‐50 wt% MA demonstrated dissimilar behavior where their m‐ZrO2 was transformed and stabilized into a cubic form by diffusion of Y3+, Mg+2, and Al+3 inside zirconia lattice. Furthermore, densification of YSZ10‐50 powder mixtures by conventional sintering at 1600°C for 2 hours resulted in fully dense compacts with micrometer‐sized grains. The outcomes indicate that MA has a significant effect on m‐ZrO2 stabilization into the cubic phase structure at room temperature. In this respect, this study offers huge potentials for developing fully stabilized c‐ZrO2 ceramics that could be possibly used as industrial ceramics for structural applications of harsh chemical and thermal environmental conditions. [ABSTRACT FROM AUTHOR]

Purpose: To explore whether radiomic features of fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography–computed tomography (PET/CT) has association with bone marrow infiltration (BMI) in comparison to other conventional PET metrics. Material and methods: Forty-four patients (with pathologically proven lymphoma disease) underwent staging 18F-FDG PET/CT scan. Primary tumour was semi-automatically or manually segmented with a threshold standardised uptake value (SUV) of 3. A total of 73 features were extracted from eight different textures. Spearman correlation was used to test the correlation of features with conventional quantitative metrics such as SUV, metabolic tumour volume, and total lesion glycolysis. Specificity and sensitivity (including 95% confidence intervals [CI]) for each of the studied parameters were derived using receiver operative characteristic (ROC) curves. Univariate and multivariate analyses were used to identify independent predictors associated with BMI. Results: Correlation between conventional PET metrics and features ranged between 0.50 and 0.97 for positive correlation (33 significant association features) and ranged from –0.52 to –0.97 for inverse correlation (three significant association features) for both strong and moderate correlations. Analysis of ROC curves showed that high-intensity long-run emphasis 4 bin, high-intensity large zone emphasis 64 bin, long-run emphasis (LRE) 64 bin, large-zone emphasis 64 bin, max spectrum 8 bin, busyness 64 bin, and code similarity 32 and 64 bin were significant discriminators of BMI among other features (area under curve > 0.682, p < 0.05). Univariate analyses of texture features showed that code similarity and long-run emphasis (both 64 bin) were significant predictors of bone marrow involvement. Multivariate analyses revealed that LRE (64 bin, p = 0.031) with an odds ratio of 1.022 and 95% CI of (1.002–1.043) were independent variables for bone marrow involvement. Conclusions: 18F-FDG PET/CT radiomic features are synergistic to visual assessment of BMI in patients diagnosed with lymphoma using 18F-FDG PET/CT. Further assessment of long-run emphasis is highly warranted. [ABSTRACT FROM AUTHOR]

Purpose . Pulsed volumetric modulated arc therapy (VMAT) was proposed as an advanced treatment that combines the biological benefits of pulsed low dose rate (PLDR) and the dosimetric benefits of the intensity-modulated beams. In our conventional pulsed VMAT technique, a daily fractional dose of 200 cGy is delivered in 10 arcs with 3 min intervals between the arcs. In this study, we are testing the feasibility of pulsed VMAT that omits the need to split into ten arcs and excludes any beam-off gaps. Methods . The study was conducted using computed tomographic images of 24 patients previously treated at our institution with the conventional PLDR technique. Our newly installed Elekta machine has a low dose rate option on the order of 25 MU min -1 . PLDR requires an effective dose rate of 6.7 cGy min -1 with attention being paid to the maximum dose received within any point within the target not to exceed 13 cGy min -1 . The quality of treatment plans was judged based on dose-volume histograms, isodose distribution, dose conformality to the target, and target dose homogeneity. The dose delivery accuracy was assessed by measurements using the MatriXX Evolution 2D array system. Results . All cases were normalized to cover 95% of the target volume with 100% of the prescription dose. The average conformity index was 1.03 ± 0.08 while the average homogeneity index was 1.05 ± 0.02. The maximum reported dose rate at any point within the target was 10.44 cGy min -1 . The mean dose rate for all pulsed VMAT plans was 6.88 ± 0.1 cGy min -1 . All cases passed our gamma analysis with an average passing rate of 99.00% ± 0.48%. Conclusion . The study showed the applicability of planning pulsed VMAT using Eclipse and its successful delivery on our Elekta linac. Pulsed VMAT using the machine's low dose rate mode is more efficient than our previous pulsed VMAT delivery., (© 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.)

Purpose: To explore whether radiomic features of fluorine-18-fluorodeoxyglucose ( 18 F-FDG) positron emission tomo-graphy-computed tomography (PET/CT) has association with bone marrow infiltration (BMI) in comparison to other conventional PET metrics., Material and Methods: Forty-four patients (with pathologically proven lymphoma disease) underwent staging 18 F-FDG PET/CT scan. Primary tumour was semi-automatically or manually segmented with a threshold standardised uptake value (SUV) of 3. A total of 73 features were extracted from eight different textures. Spearman correlation was used to test the correlation of features with conventional quantitative metrics such as SUV, metabolic tumour volume, and total lesion glycolysis. Specificity and sensitivity (including 95% confidence intervals [CI]) for each of the studied parameters were derived using receiver operative characteristic (ROC) curves. Univariate and multivariate analyses were used to identify independent predictors associated with BMI., Results: Correlation between conventional PET metrics and features ranged between 0.50 and 0.97 for positive correlation (33 significant association features) and ranged from -0.52 to -0.97 for inverse correlation (three significant association features) for both strong and moderate correlations. Analysis of ROC curves showed that high-intensity long-run emphasis 4 bin, high-intensity large zone emphasis 64 bin, long-run emphasis (LRE) 64 bin, large-zone emphasis 64 bin, max spectrum 8 bin, busyness 64 bin, and code similarity 32 and 64 bin were significant discriminators of BMI among other features (area under curve > 0.682, p < 0.05). Univariate analyses of texture features showed that code similarity and long-run emphasis (both 64 bin) were significant predictors of bone marrow involvement. Multivariate analyses revealed that LRE (64 bin, p = 0.031) with an odds ratio of 1.022 and 95% CI of (1.002-1.043) were independent variables for bone marrow involvement., Conclusions: 18 F-FDG PET/CT radiomic features are synergistic to visual assessment of BMI in patients diagnosed with lymphoma using 18 F-FDG PET/CT. Further assessment of long-run emphasis is highly warranted., Competing Interests: The authors report no conflict of interest., (© Pol J Radiol 2020.)