Numerical Detection of Cavitation Damage on Dam Spillway

The present paper deals with the numerical detection of cavitation damage level and location on dam spillways. At first, flow over a spillway was simulated using the computational fluid dynamics method. The flow characteristics such as pressure, velocity and depth through the spillway have been calculated for five different flow rates. Since the actual flow is turbulent, the RNG turbulence model has been used for simulation. The numerical results of flow characteristics including flow depth, velocity and pressure were compared with the available results of the hydraulic model tests. The numerical results agreed well with the experimental data, and reasonable values for the normalized root mean square error (NRMSE= 0.0476) and coefficient of determination (r2=0.8354) indicated that the numerical model is accurate. Finally occurrence of cavitation damage to the Doosti dam spillway was investigated. Based on cavitation index, five different damage levels from no damage to major damage have been considered. Results showed that the spillway may be at the risk of cavitation damage, and the serious damage can occur at ending parts of the structure

Assessment of image quality and dose calculation accuracy on kV CBCT, MV CBCT, and MV CT images for urgent palliative radiotherapy treatments.

A clinical workflow was developed for urgent palliative radiotherapy treatments that integrates patient simulation, planning, quality assurance, and treatment in one 30-minute session. This has been successfully tested and implemented clinically on a linac with MV CBCT capabilities. To make this approach available to all clinics equipped with common imaging systems, dose calculation accuracy based on treatment sites was assessed for other imaging units. We evaluated the feasibility of palliative treatment planning using on-board imaging with respect to image quality and technical challenges. The purpose was to test multiple systems using their commercial setup, disregarding any additional in-house development. kV CT, kV CBCT, MV CBCT, and MV CT images of water and anthropomorphic phantoms were acquired on five different imaging units (Philips MX8000 CT Scanner, and Varian TrueBeam, Elekta VersaHD, Siemens Artiste, and Accuray Tomotherapy linacs). Image quality (noise, contrast, uniformity, spatial resolution) was evaluated and compared across all machines. Using individual image value to density calibrations, dose calculation accuracies for simple treatment plans were assessed for the same phantom images. Finally, image artifacts on clinical patient images were evaluated and compared among the machines. Image contrast to visualize bony anatomy was sufficient on all machines. Despite a high noise level and low contrast, MV CT images provided the most accurate treatment plans relative to kV CT-based planning. Spatial resolution was poorest for MV CBCT, but did not limit the visualization of small anatomical structures. A comparison of treatment plans showed that monitor units calculated based on a prescription point were within 5% difference relative to kV CT-based plans for all machines and all studied treatment sites (brain, neck, and pelvis). Local dose differences >5% were found near the phantom edges. The gamma index for 3%/3 mm criteria was ≥95% in most cases. Best dose calculation results were obtained when the treatment isocenter was near the image isocenter for all machines. A large field of view and immediate image export to the treatment planning system were essential for a smooth workflow and were not provided on all devices. Based on this phantom study, image quality of the studied kV CBCT, MV CBCT, and MV CT on-board imaging devices was sufficient for treatment planning in all tested cases. Treatment plans provided dose calculation accuracies within an acceptable range for simple, urgently planned palliative treatments. However, dose calculation accuracy was compromised towards the edges of an image. Feasibility for clinical implementation should be assessed separately and may be complicated by machine specific features. Image artifacts in patient images and the effect on dose calculation accuracy should be assessed in a separate, machine-specific study. PACS number(s): 87.55.D-, 87.57.C-, 87.57.Q

Asymmetrically Difunctionalized 1,1′-Ferrocenyl Metalloligands and Their Transition Metal Complexes

FcBipy: Novel redox-active bipyridine ligands based on 1,1′ difunctionalized ferrocenyl backbone, in conjunction with their metal complexes, are reported. The influence of the implemented functional groups on both the iron-centred redox potential and the N,N′-coordinated nickel complexes were confirmed for the reductive elimination reaction of an aryl ether induced by oxidation of the corresponding methoxides

Biochemical, ameliorative and cytotoxic effects of newly synthesized curcumin microemulsions: Evidence from in vitro and in vivo studies

Curcumin is known to exhibit antioxidant and tissue-healing properties and has recently attracted the attention of the biomedical community for potential use in advanced therapies. This work reports the formulation and characterization of oil-in-water F127 microemulsions to enhance the bioavailability of curcumin Microemulsions showed a high encapsulation efficiency and prolonged release. To investigate the interactions of curcumin with one unit of the polymeric chain of surfactant F127, ethyl butyrate, and sodium octanoate, as well as the interaction between ethyl butyrate and one unit of the F127 polymer chain, the Density Functional Theory (DFT) calculations at the M06-2X level of theory, were performed in water solution. The MTT assay was used to assess the cytotoxicity of free and encapsulated curcumin on non-malignant and malignant cell lines. Combination effects were calculated according to Chou-Talalay’s principles. Results of in vitro studies indicated that MCF7 and HepG2 cells were more sensitive to curcumin microemulsions. Moreover, a synergistic relationship was observed between curcumin microemulsions and cisplatin in all affected fractions of MCF7 and HepG2 cells (CI < 0.9). For in vivo investigation, thioacetamide-intoxicated rats received thioacetamide (100 mg/kg Sc) followed by curcumin microemulsions (30 mg/kg Ip). Thioacetamideintoxicated rats showed elevated serum liver enzymes, blood urea nitrogen (BUN), and creatinine levels, and a significant reduction in liver superoxide dismutase (SOD) and catalase (CAT) activities (p < 0.05). Curcumin microemulsions reduced liver enzymes and serum creatinine and increased the activity of antioxidant enzymes in thioacetamide-treated rats in comparison to the untreated thioacetamide-intoxicated group. Histopathological investigations confirmed the biochemical findings. Overall, the current results showed the desirable hepatoprotective, nephroprotective, and anti-cancer effects of curcumin microemulsions

Cavitation Damage Prediction on Dam Spillways using Fuzzy-KNN Modeling

The present paper deals with a numerical method for prediction of cavitation damage level and location on dam spillways. A method was applied to predict the intensity of cavitation damage to spillways, using the fuzzy k-nearest neighbor algorithm. Five levels of damage intensity were considered to predict cavitation damage in the spillway of Karun-1 Dam in Iran. According to the results, the proposed model could properly predict the location and intensity of damage in comparison with the actual damage reports of past floods. According to the Pearson's correlation coefficient, mean absolute error, coefficient of residual mass, and normalized root mean square error, the fuzzy k-nearest neighbor model is efficient and suitable

Drought Monitoring and Prediction using K-Nearest Neighbor Algorithm

Drought is a climate phenomenon which might occur in any climate condition and all regions on the earth. Effective drought management depends on the application of appropriate drought indices. Drought indices are variables which are used to detect and characterize drought conditions. In this study, it was tried to predict drought occurrence, based on the standard precipitation index (SPI), using k-nearest neighbor modeling. The model was tested by using precipitation data of Kerman, Iran. Results showed that the model gives reasonable predictions of drought situation in the region. Finally, the efficiency and precision of the model was quantified by some statistical coefficients. Appropriate values of the correlation coefficient (r=0.874), mean absolute error (MAE=0.106), root mean square error (RMSE=0.119) and coefficient of residual mass (CRM=0.0011) indicated that the present model is suitable and efficien

Cooperativity‐Driven Reactivity of a Dinuclear Copper Dimethylglyoxime Complex

In this report, we present the dinuclear copper(II) dimethylglyoxime (H$_2$dmg) complex [Cu$_2$(H$_2$dmg)(Hdmg)(dmg)]$^+$ (1), which, in contrast to its mononuclear analogue [Cu(Hdmg)$_2$] (2), is subject to a cooperativity-driven hydrolysis. The combined Lewis acidity of both copper centers increases the electrophilicity of the carbon atom in the bridging μ$_2$-O−N=C-group of H$_2$dmg and thus, facilitates the nucleophilic attack of H2O. This hydrolysis yields butane-2,3-dione monoxime (3) and NH$_2$OH that, depending on the solvent, is then either oxidized or reduced. In ethanol, NH$_2$OH is reduced to NH$_4$$^+$, yielding acetaldehyde as the oxidation product. In contrast, in CH$_3$CN, NH$_2$OH is oxidized by Cu$^{II}$ to form N$_2$O and [Cu(CH$_3$CN)4]$^+$. Herein are presented the combined synthetic, theoretical, spectroscopic and spectrometric methods that indicate and establish the reaction pathway of this solvent-dependent reaction

Knowledge co-production with traditional herders on cattle grazing behaviour for better management of species-rich grasslands

The research gap between rangeland/livestock science and conservation biology/vegetation ecology has led to a lack of evidence needed for grazing-related conservation management. Connecting scientific understanding with traditional ecological knowledge of local livestock keepers could help bridge this research and knowledge gap. We studied the grazing behaviour (plant selection and avoidance) of beef cattle (c. 33,000 bites) on species-rich lowland pastures in Central Europe and traditional herding practices. We also did >450 outdoor interviews with traditional herders about livestock behaviour, herders' decisions to modify grazing behaviour and effects of modified grazing on pasture vegetation. We found that cattle grazing on species-rich pastures displayed at least 10 different behavioural elements as they encountered 117 forage species from highly desired to rejected. The small discrimination error suggests that cattle recognize all listed plants ‘by species’. We also found that herders had broad knowledge of grazing desire and they consciously aimed to modify desire by slowing, stopping or redirecting the herd. Modifications were aimed at increasing grazing intensity in less-desired patches and decreasing grazing selectivity in heterogenous swards. Synthesis and applications. The traditional herd management practices presented here have significant conservation benefits, such as avoiding under- and overgrazing, and targeted removal of pasture weeds, litter and encroaching bushes, tall competitive plants and invasive species. We argue that knowledge co-production with traditional herders who belong to another knowledge system could help connect isolated scientific disciplines especially if ecologists and rangeland scientists work closely with traditional herders, co-designing research projects and working together in data collection, analysis and interpretation. Stronger links between these disciplines could help develop evidence-based, specific conservation management practices while herders could contribute with their practical experiences and with real-world testing of new management techniques.Fil: Molnár, Zsolt. Institute of Ecology and Botany; HungríaFil: Kelemen, András. Institute of Ecology and Botany; HungríaFil: Kun, Róbert. Szent István University. Department of Nature Conservation and Landscape Ecology; HungríaFil: Máté, János. Cattle Herder, Tatárszentgyörgy; HungríaFil: Sáfián, László. Cattle Herder, Tatárszentgyörgy; HungríaFil: Provenza, Fred. University of Utah; Estados UnidosFil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Barani, Hossein. Gorgan University of Agricultural Sciences and Natural Resources; IránFil: Biró, Marianna. GINOP Sustainable Ecosystems Group; HungríaFil: Máté, András. Dorcadion Kft; HungríaFil: Vadász, Csaba. Kiskunság National Park; Hungrí

Trends in the representation of women in the American Society of Pediatric Nephrology program at the Pediatric Academic Society annual meetings 2012–2021

IntroductionWomen are under-represented in virtually all fields of academic medicine. Even in pediatrics, a field that historically attracts a workforce with a majority of women physicians, substantial gender disparities persist in leadership positions. However, previous studies of gender representation in various academic settings are limited to small studies or aggregate pediatric subspecialties, thereby omitting important granularity within each subspecialty. No prior studies have investigated potential gender disparities in pediatric nephrology. The aim of this study is to determine the representation of women physicians in leadership and speaking roles in the annual American Society of Pediatric Nephrology (ASPN) meeting.MethodsData were analyzed from the 2012–2022 ASPN annual scientific meetings at the Pediatric Academic Society (PAS). Data were abstracted regarding gender and roles: speaker, chair/moderator, and lifetime achievement awardee. We performed a time series analysis using linear regression, with the year as the independent variable and the proportion of women as the dependent variable.ResultsOverall, there were statistically significant increases in the proportion of women speakers per year and percentage of women chairs or moderators. There were no specific trends noted for lifetime achievement awards and no statistically significant changes in the number of lifetime achievement awards.DiscussionWe found proportionate representations of gender representation with regards to speakers and chairs or moderators, although our data was limited by comparison to the American Board of Pediatrics (ABP) workforce cumulative “ever certified” data. The ABP data include a disproportionate representation of faculty who are men from earlier certification periods who may no longer be actively practicing pediatric nephrology