Composite Plan Research Articles

Adsorption of cobalt isotope from liquid radioactive waste by carbon nanostructured materials of thermochemical activation of sludge-lignin

One of the urgent problems of modern industry is the accumulation of waste. Waste from the nuclear industry is liquid radioactive waste, pulp and paper industry is sludgelignin. To solve the problem of waste accumulation in these industries, a method of selective purification of liquid radioactive waste by waste products of the pulp and paper industry is proposed. Pyrolysis is an effective way of processing sludge-lignin, as a result of the activation of the pyrolysis product by alkaline reagents, activated carbons were obtained in laboratory conditions, which presumably can selectively extract isotopes of radionuclides from liquid radioactive waste. In the conducted study, the ability of carbon nanostructured materials of thermochemical activation of sludge-lignin to extract the isotope Со27 59 in the form of an ammonia complex was studied. The influence of the pyrolysis conditions: temperature (T), time (T) and dosage of the activator (D) on the response functions: monolayer capacity, heat of adsorption, the value of the maximum adsorption and the characteristic adsorption energy, which can be used to judge the porous structure of activated carbon. The method of the planned experiment is applied — rotatable central composite plan. For clarity, response surfaces are constructed based on experimental data. The analysis made it possible to develop practical recommendations for conducting the pyrolysis process in order to obtain a marketable product — activated carbons from sludge–lignin.

The response of radiation detectors in modulated fields for small targets

Intensity-modulated delivery techniques in radiotherapy are advanced methods that use the superposition of small fields to create complex dose distributions. These techniques result in intense gradients and inhomogeneous dose regions, making the dosimetry of composite fields challenging, especially when the sub-fields superposition does not restore charged particle equilibrium. This work aims to address the response of radiation detectors in non-equilibrium conditions. Two ionization chambers and a micro-diamond detector were irradiated using composite fields from VMAT plans with spherical targets with diameters ranging from 0.5 to 8 cm. The radiation detectors' response and the dose delivered by the VMAT plans were measured using a plastic scintillator detector and radiochromic film as reference detectors. It was observed that an under-response of the ionization chambers was up to 13% and an over-response of the micro-diamond detector was up to 2.5%. Additionally, output correction factors were derived and used to measure the absorbed dose in composite plans using the radiation detectors. The measured dose was compared with that measured with radiochromic film. A dose difference was found within radiochromic film uncertainties (<2.5%). The results of this work suggest that radiation detectors require output correction factors when non-equilibrium conditions persist in composite fields. However, a link between static and composite fields could not be established because the field size cannot be determined accurately.

Caffeine crystallization optimization and kinetics

Caffeine is widely used in the chemical, food and pharmaceutical industries. Understanding their behavior during crystallization processes is of fundamental importance to elucidate the dynamics of crystalline growth. In this context, the present study aimed to investigate the variables that influence crystallization by reducing the temperature in saturated caffeine solutions, following the evolution of crystals during the aqueous crystallization phase. To achieve this purpose, a Central Composite Planning (PCC) was conducted with 18 experiments, in which supersaturation, agitation and crystallization time were analyzed in relation to the yield of the caffeine mass. The growth kinetics of the crystals were evaluated by quantifying the mass of the crystals and the concentration of the solution, as well as observing growth under an optical microscope. The average yield obtained at crystallization was 285.6%, and it is evident that the agitation exerted the greatest influence on the process yield, followed by supersaturation, while the crystallization time proved less significant. The responses indicated a crystalline growth of the seeds added in all the experiments of the PCC. In terms of kinetics, experimental data were correlated using the method proposed by Mullin. The results showed an increase in the mass of the crystals throughout the operation, however, the characteristic dimension decreased due to the acicular geometry of the caffeine crystals, which favors the longitudinal breakdown of the latter

ПОШИРЕНІСТЬ ПЕРЕРОБКИ ЗОЛИ ПРИ ВИГОТОВЛЕННІ БУДІВЕЛЬНИХ МАТЕРІАЛІВ

The object of research in the work is the waste of thermal energy enterprises, the annual volume of which in Ukraine is 8 million tons, and the increase in occupied land areas is 22 thousand hectares. In EU countries, up to 84% of such waste is recycled. Therefore, forecasting the prevalence of ash processing in the manufacture of building materials in different countries of the world from the main parameters of influence in order to solve the problem of solid industrial waste management is an urgent scientific and technical task. A study of the prevalence of ash processing in the manufacture of building materials in different countries of the world was conducted by planning a second-order experiment using the Box-Wilson method using rotatable central composite planning using the developed software protected by a copyright certificate. The purpose of the study is to determine a regression model for predicting the prevalence of ash processing in the manufacture of building materials in different countries of the world from the main parameters of influence. A regression dependence of forecasting the prevalence of ash processing in the manufacture of building materials on the main parameters of influence was obtained: the country's population density, the value of the gross domestic product per capita, the average geographical latitude of the country. It was established that, according to Fisher's test, the hypothesis about the adequacy of the obtained regression model can be considered correct with 95% confidence. The correlation coefficient was 0.99999, which indicates sufficient reliability of the obtained results. The obtained regression dependence can be used during the development of a construction waste management strategy. It was established that among the factors of influence that were considered, the prevalence of ash processing in the manufacture of building materials is most affected by the value of the gross domestic product per capita, and the least by the population density of the country. Response surfaces of the target function - the prevalence of ash processing in the production of building materials and their two-dimensional sections in the planes of the influence parameters - were constructed.

The Dosimetric Analysis of Duodenal and Intestinal Toxicity After a Curative Dose Re-irradiation Using the Intensity-Modulated Radiotherapy for Abdominopelvic Lymph Node Lesions.

This study aimed to examine the influence of dosimetric factors on gastrointestinal toxicity after radical re-irradiation for lymph node recurrence in the abdominopelvic region using a composite plan. Between January 2008 and March 2017, 33 patients underwent radical re-irradiation for lymph node recurrence in the abdominopelvic region with a complete overlap with previous radiation therapy (RT) with the median prescription dose of the second RTof 71.7 Gy10.Re-irradiation planning protocol for target volume and organs at risk (OARs) (duodenum, small and large intestines) was decided as follows: more than equal to 97% of the prescription dose was administered to the D95 (percentage of the minimum dose that covered 95% of the target volume) of planning target volume (PTV); minimal dose to the maximally irradiated doses delivered to 1cc [D1 cc] and 5cc [D5 cc] of OARs was set below 70 Gy3 and 50 Gy3, respectively; and D1 cc and D5 cc in the cumulative plans to OARs were 120 Gy3 and 100 Gy3.Kaplan-Meier analyses were performed to evaluate overall survival (OS) and univariate log-rank and multivariate Cox proportional hazards model analyses were performed to explore predictive factors. Using dose summation of the first and re-irradiation plans, we conducted a dosimetric analysis for grade ≥ 3 toxicities of the duodenum and intestine. With a median follow-up of 18 months, the two-year OSrate was 45.5%. The number of RT fields (localized or multiple) was a significant predisposing factor for OS rate with a hazard ratio of 0.23 (95% confidence interval 0.07-0.73). The two-year OS of the patients with a localized RT field was 63.6% and 9.1% for multiple RT fields (p= 0.00007). Four patients experienced grade ≥3 gastrointestinal toxicity related to re-irradiation (4/33=12.1%). We could not find any predisposing dosimetric value in the comparisons with and without toxicity. The dose constraints presented in this study are relatively low rates of toxicity, which may be useful when planning re-irradiation. Especially, for the patients who could be treated with localized RT field, radical re-irradiation with a high curative dose is a good option. No dosimetric predisposing factor was found for radical re-irradiation of abdominopelvic lesions in the composite plan.

Study of the influence of the current distortion power of the secondary winding of a transformer on the level of losses in it using the method of experiment planning

Purpose. Detection the relationship between the level of losses of a three-phase transformer and the power of distortion caused by current harmonics.. Methodology. During the research, the methods of determining power losses and additional losses in the elements of the electrical system from higher current and voltage harmonics, the visual programming method, the experiment planning method, and the orthogonal central composite plan method were used. Findings. An analysis of the indicators characterizing voltage and current distortions was carried out, and it was found that these distortions are most fully characterized by the current distortion power and voltage distortion power. These indicators are used to analyze the transmission of electric energy by a transformer of a traction substation. It is noted that the order of harmonics in the distortion power is not eliminated, and higher harmonics are taken into account by the corresponding effective current of higher harmonics. The specifics of the transformer secondary winding connections to the consumer, namely the grounding of one of the secondary winding phases, were taken into account. A number of combinations of current harmonics were used to simulate current distortions. The experiment was carried out using the planning method. The coefficients of the quadratic regression equation that relates power losses to the level of load current harmonics of the third, fifth, and seventh orders are obtaine To determine the significance of the obtained coefficients of the regression equation, the variances and the corresponding values of the Student's criterion were calculated, as a result, factors that do not affect the process and can be excluded from the regression equation were identified. The adequacy of the obtained regression equation was checked by Fisher's criterion. The analysis of the effects and their interaction showed that the standard error of the sample does not exceed 1.66%. As a result of analyzing the combinations of current harmonics that were set during the experiment, it was noted that some of them lead to the same effective phase current, while the power of current distortion is different. The greatest significance of the level of the third harmonic of the current is determined. The constant level of active power on the high voltage side of the transformer is noted, which is due to the absence of voltage distortions on it. Originality. Cases of combinations of current harmonic levels at which the current distortion power index remains unchanged, while the level of transformer power losses caused by current harmonics changes, have been identified. Practical value. This research can be used to assess and reduce the level of power losses in a transformer by filtering certain current harmonics.

Novel combination of GammaTile cesium-131 brachytherapy with 5-aminolevulinic acid fluorescence-guided resection in the re-irradiation of pediatric recurrent high-grade glioma: illustrative case.

Herein, the authors describe the successful utilization of 5-aminolevulinic acid (5-ALA) and the first case of GammaTile cesium-131 therapy in a pediatric patient with recurrent high-grade glioma. 5-ALA was utilized to optimize gross-total resection prior to GammaTile implantation. After conversion to an equivalent dose in 2-Gy fractions (EQD2), a composite was made of the GammaTile dose with the initial external beam radiotherapy. Two hypothetical plans consisting of a standard hypofractionated strategy for glioma reirradiation and a CyberKnife plan using GammaTile's planning target volume were developed and likewise underwent EQD2 conversion and composite plan generation with the initial radiotherapy. 5-ALA was useful in achieving gross-total resection with no acute toxicity from the surgery or GammaTile irradiation. When compared with the hypothetical composite doses, GammaTile's composite, axium point dose (D0.03cc) to the brainstem was 32.9 Gy less than the hypofractionated and the CyberKnife composite plans at 38.7 Gy and 40.2 Gy, respectively. The right hippocampus demonstrated a substantially reduced composite plan dose with GammaTile with a D0.03cc of 62.4 Gy versus 71.7 and 80.7 Gy for the hypofractionated and CyberKnife composite plans, respectively. Utilization of 5-ALA and GammaTile therapy yielded clinically superior tumor debulking and effective radiotherapy dose localization with sparing of organs at risk, respectively.

A sub-analysis of multi-center planning radiosurgery for intracranial metastases through automation (MC-PRIMA) comparing UK and international centers

A sub-analysis of the MC-PRIMA study was performed to compare the plan quality of stereotactic radiosurgery (SRS) to multiple brain metastases (MBM) between UK and other international centres. Six centres from the UK and nineteen from other international centres autoplanned using Multiple Brain Mets™ (AutoMBM; Brainlab, Munich, Germany) software for a five MBM study case from a prior planning competition that was originally organized by the Trans-Tasmania Radiation Oncology Group (TROG). Twenty-three dosimetric metrics and the resulting composite plan score per the TROG planning competition were compared between the UK and other international centres. Planning experience and planning time from each planner were recorded and statistically compared. Planning experiences between two groups are equal. Except for mean dose to the hippocampus, all other 22 dosimetric metrics were comparable between two groups. The inter-planner variations in these 23 dosimetric metrics and the composite plan score were also statistically equivalent. Planning time is slightly longer in the UK group (mean = 86.8 min) with a mean difference of 50.3 min. AutoMBM effectively achieves standardization of the plan quality of SRS to MBM within UK and further against the other international centres. Significant planning efficiency gain by AutoMBM both among the UK and other international centres may help to increase the capacity of SRS service by alleviating the clinical and technical loadings.

Clinical and Dosimetric Risk Factors Associated With Radiation-Induced Lung Toxicities After Multiple Courses of Lung Stereotactic Body Radiation Therapy

Data are limited on radiation-induced lung toxicities (RILT) after multiple courses of lung stereotactic body radiation therapy (SBRT). We herein analyze a large cohort of patients to explore the clinical and dosimetric risk factors associated with RILT in such settings. A single institutional database of patients treated with multiple courses of lung SBRT between January 2014 and December 2019 was analyzed. Grade 2 or higher (G2+) RILT after the last course of SBRT was the primary endpoint. Composite plans were generated with advanced algorithms including deformable registration and equivalent dose adjustment. Logistic regression analyses were performed to examine correlations between patient or treatment factors including dosimetry and G2+ RILT. Risk stratification of patients and lung constraints based on acceptable normal tissue complication probability were calculated based on risk factors identified. Among 110 eligible patients (56 female and 54 male), there were 64 synchronous (58.2%; defined as 2 courses of SBRT delivered within 30 days) and 46 metachronous (41.8%) courses of SBRT. The composite median lung V20, lung V5, and mean lung dose were 9.9% (interquartile range [IQR], 7.3%-12.4%), 32.2% (IQR, 25.5%-40.1%), and 7.0 Gy (IQR, 5.5 Gy-8.6 Gy), respectively. With a median follow-up of 21.1 months, 30 patients (27.3%) experienced G2+ RILT. Five patients (4.5%) developed G3 RILT, and 1 patient (0.9%) developed G4 RILT, and no patients developed G5 RILT. On multivariable regression analysis, female sex (odds ratio [OR], 4.35; 95% CI, 1.49%-14.3%; P=.01), synchronous SBRT (OR, 8.78; 95% CI, 2.27%-47.8%; P=.004), prior G2+ RILT (OR, 29.8; 95% CI, 2.93%-437%; P=.007) and higher composite lung V20 (OR, 1.18; 95% CI, 1.02%-1.38%; P=.030) were associated with significantly higher likelihood of G2+ RILT. Our data suggest an acceptable incidence of G2+ RILT after multiple courses of lung SBRT. Female sex, synchronous SBRT, prior G2+ RILT, and higher composite lung V20 may be risk factors for G2+ RILT.

A Determination of the Influence of Technological Parameters on the Quality of the Created Layer in the Process of Cataphoretic Coating

Cataphoresis varnishing enables an organic coating to form on an aluminum substrate, thus increasing its corrosion resistance and durability. Cataphoresis varnishing is known to ensure a high adhesion of the created cataphoresis layer and a good homogeneity of this layer, even on surfaces with complex geometry. This paper aimed to optimize the deposition process and to analyze and evaluate the thickness of a cataphoresis layer formed on an aluminum substrate from AW 1050—H24 material. In total, 30 separate samples were created in accordance with the Design of Experiments methodology, using a central composite plan. The independent input factors in the study were: the electrical voltage (U) and deposition time in the cataphoresis varnishing process (tKTL) at the polymerization times of 15 min, 20 min, and 25 min, respectively. The results of the statistical analysis showed that the voltage accounted for 33.82% of the change in the thickness of the created layer and the deposition time contributed 28.67% to thi change. At the same time, the interaction of the voltage and deposition time (p &lt; 0.0001) accounted for 20.25% of the change in the thickness of the layer under formation. The regression model that was constructed showed a high degree of prediction accuracy (85.8775%) and its use as a function for nonlinear optimization provided a maximum layer thickness th of max = 26.114 µm, at U = 240 V and tKTL = 6.0 min, as was proven under experimental conditions.

Analysis of Bagasse Cellulose-Based Hydrogel for Methylene Blue Removal from Textile Industry Wastewater

The textile industry is one of the biggest water consumption production areas and its waste is essential to cause ecological contamination as they deliver questionable color, weighty metal, and degradable natural and inorganic results whenever arranged without treatment. The natural treatment strategy is not broadly drilled because of its intricate method. In the adsorption method, for example, actuated carbon was limited by prudence of its significant expense and low adsorption limit. This study has completed the combination and portrayal of bagasse cellulose-based hydrogel for the expulsion of methylene blue color from textile industry wastewater. The study furnishes a major critical contributing option for biodegradable adsorption material by supplanting the conventional color evacuation method with a nonconventional one that showsthe attainability of horticultural waste for a union of the hydrogel as opposed to noninexhaustible petrochemical based and show the capability of involving hydrogel for the expulsion of harmful contamination from the textile industry. The hydrogel was combined utilizing free extreme polymerization that can utilize acrylic corrosive (AA) and citrus extract as cross-connecting specialists and monomers individually. FTIR, XRD, and conduct metric titration are the primary hardware utilized for the portrayal of the hydrogel. The cycle boundaries that can influence the color evacuation proficiency of hydrogel, for example, pH, contact time, and temperature have been examined. A focal composite plan by rotatable component is the technique used to browse reaction surface strategies to control the tests with the communication of cycle boundaries.

Automating the treatment planning process for 3D-conformal pediatric craniospinal irradiation therapy.

Pediatric patients with medulloblastoma in low- and middle-income countries (LMICs) are most treated with 3D-conformal photon craniospinal irradiation (CSI), a time-consuming, complex treatment to plan, especially in resource-constrained settings. Therefore, we developed and tested a 3D-conformal CSI autoplanning tool for varying patient lengths. Autocontours were generated with a deep learning model trained:tested (80:20 ratio) on 143 pediatric medulloblastoma CT scans (patient ages: 2-19years, median=7years). Using the verified autocontours, the autoplanning tool generated two lateral brain fields matched to a single spine field, an extended single spine field, or two matched spine fields. Additional spine subfields were added to optimize the corresponding dose distribution. Feathering was implemented (yielding nine to 12 fields) to give a composite plan. Each planning approach was tested on six patients (ages 3-10years). A pediatric radiation oncologist assessed clinical acceptability of each autoplan. The autocontoured structures' average Dice similarity coefficient ranged from .65 to .98. The average V95 for the brain/spinal canal for single, extended, and multi-field spine configurations was 99.9%±0.06%/99.9%±0.10%, 99.9%±0.07%/99.4%±0.30%, and 99.9%±0.06%/99.4%±0.40%, respectively. The average maximum dose across all field configurations to the brainstem, eyes (L/R), lenses (L/R), and spinal cord were 23.7±0.08, 24.1±0.28, 13.3±5.27, and 25.5±0.34Gy, respectively (prescription=23.4Gy/13 fractions). Of the 18 plans tested, all were scored as clinically acceptable as-is or clinically acceptable with minor, time-efficient edits preferred or required. No plans were scored as clinically unacceptable. The autoplanning tool successfully generated pediatric CSI plans for varying patient lengths in 3.50±0.4minutes on average, indicating potential for an efficient planning aid in a resource-constrained settings.

Пошук оптимальних параметрів фінішної антифрикційної безабразивної обробки гільз циліндрів автотракторних двигунів

This paper presents the results of research aimed at improving the quality of antifriction coatings obtained by finishing antifriction non-abrasive treatment (FANT). It has been previously established that the formation of an antifriction coating during FANT largely depends on the technological parameters that determine the conditions of contact between the tool and the surface being treated. The study of the peculiarities of surface contact, their regularities, as well as the main parameters of the FANT process, makes it possible to improve the quality of the antifriction coating, and therefore the operational properties of the part. The aim of the presented research is to evaluate the influence of technological factors of the FANT process on the quality of antifriction coatings and to obtain their rational values. The indicators of the quality of the antifriction coating are its continuity, surface roughness and mass transfer of the antifriction material. The optimisation parameters are the main modes of FANT and the geometrical characteristics of the initial surface to be treated. To determine the influence of the selected factors on the indicators characterising the quality of the antifriction coating, a central composite plan matrix was implemented, which allowed us to obtain mathematical models of the influence of factors on the adopted response functions. The processing of the experimental data was carried out using the STATISTICA 12.0 software package. As a result of the multifactorial experiment, statistical models were obtained that allow assessing the impact of the studied factors on the optimisation criteria. The significance of the obtained coefficients was checked using the Student's criterion, and the adequacy of the obtained equations was checked using the Fisher's criterion. A detailed analysis of the Pareto map and tabular results of the experiment allowed to establish the influence of the research factors on the optimisation criteria. The obtained mathematical models made it possible to determine the optimal combination of technological factors that ensure the quality of the coating, as well as to establish the rational values of FANT modes and geometric characteristics of the output surface.

Developing an effective deflector for duct natural ventilation

Information is given on increasing the available gravitational pressure of natural duct ventilation by increasing the use of wind flow energy. The scheme and operation of the developed deflector with a vertical finned cylindrical surface based on the CAI deflector are described. The laboratory bench scheme developed and patented for evaluating the efficiency of various types of deflectors is presented. Thermo-anemometer was used in experimental studies as instrumentation TKA-PKM (52), as well as a wing type anemometer. The effectiveness of the developed deflector was evaluated using the mathematical method of planning and processing of experiments. Scientific and experimental investigations were carried out on the basis of an orthogonal composite plan of the first order. A complete factorial experiment was carried out in CFE 23. A regression equation adequately describes the influence of the design and process parameters on the air velocity in the natural ventilation duct at the significance level = 0.05. Experimental studies have confirmed that it is possible to increase the degree of utilization of wind stream energy when it flows over a vertical finned cylindrical surface in comparison with a smooth cylindrical surface. It is shown that air velocity in exhaust duct can be increased up to values of 3.35 m/s. α

A Simulation Study of Tolerance of Breathing Amplitude Variations in Radiotherapy of Lung Cancer Using 4DCT and Time-Resolved 4DMRI.

As patient breathing irregularities can introduce a large uncertainty in targeting the internal tumor volume (ITV) of lung cancer patients, and thereby affect treatment quality, this study evaluates dose tolerance of tumor motion amplitude variations in ITV-based volumetric modulated arc therapy (VMAT). A motion-incorporated planning technique was employed to simulate treatment delivery of 10 lung cancer patients' clinical VMAT plans using original and three scaling-up (by 0.5, 1.0, and 2.0 cm) motion waveforms from single-breath four-dimensional computed tomography (4DCT) and multi-breath time-resolved 4D magnetic resonance imaging (TR-4DMRI). The planning tumor volume (PTV = ITV + 5 mm margin) dose coverage (PTV D95%) was evaluated. The repeated waveforms were used to move the isocenter in sync with the clinical leaf motion and gantry rotation. The continuous VMAT arcs were broken down into many static beam fields at the control points (2°-interval) and the composite plan represented the motion-incorporated VMAT plan. Eight motion-incorporated plans per patient were simulated and the plan with the native 4DCT waveform was used as a control. The first (D95% ≤ 95%) and second (D95% ≤ 90%) plan breaching points due to motion amplitude increase were identified and analyzed. The PTV D95% in the motion-incorporated plans was 99.4 ± 1.0% using 4DCT, closely agreeing with the corresponding ITV-based VMAT plan (PTV D95% = 100%). Tumor motion irregularities were observed in TR-4DMRI and triggered D95% ≤ 95% in one case. For small tumors, 4 mm extra motion triggered D95% ≤ 95%, and 6-8 mm triggered D95% ≤ 90%. For large tumors, 14 mm and 21 mm extra motions triggered the first and second breaching points, respectively. This study has demonstrated that PTV D95% breaching points may occur for small tumors during treatment delivery. Clinically, it is important to monitor and avoid systematic motion increase, including baseline drift, and large random motion spikes through threshold-based beam gating.

Plan and Analysis of A Lightweight Composite Transporting Container Made of Carbon Fiber Laminates

The writing demonstrates that a 20% decrease in the heaviness of void 40-foot transporting compartments would result in $28 billion of fuel reserve funds, alongside a 3.6 exajoule decrease in the energy request over holders’ 15-year lifetime. Diminishing the energy interest and subsequently nursery gas outflows by using lightweight steel trailers has been a neglected methodology. In this respect, this study researches the chance of additional lessening the heaviness of an unfilled holder without compromising the primary respectability, strength, and capability of a customary steel compartment. This examination sees that as up to a 80% decrease in weight is conceivable by creating steel trailers with composite materials. This examination presents the new plan of a 40-foot holder made of carbon fiber overlays. The tare weight of a conventional 40-foot transporting compartment is around 3750 Kg. In actuality, in this examination, the heaviness of a composite plan of a similar compartment is determined to be around 822 Kg. Extra tests with different burdens, for example, lifting the compartment and stacking loads onto the composite compartment, are performed to investigate the strength and clasping issues of the plan introduced in this review. The investigations uncover that the composite steel trailer is an exceptionally encouraging possibility for lessening ozone harming substance outflows, giving fuel reserve funds and consequently lessening the functional expenses of transportation.

Portal dosimetry correction method for validation of single isocenter VMAT plans for multiple brain metastases.

Portal dosimetry is one option for verification of volumetric‐modulated arc therapy (VMAT) planning for multiple brain metastases. However, due to the changing response of the portal imager with photon beam energy, the dose transmitted through closed multileaf collimator (MLC) leaves or narrow MLC gaps may be underestimated by the imager.We present a simple method for correcting for these effects that may be implemented within the Eclipse treatment planning system. We recalculated the predicted portal dose with and without this correction for 20 multiple brain met VMAT plans. Before the correction, 3/20 composite plan fields passed our standard quality assurance (QA) criteria (54/80 individual fields); the average gamma passing rate for the composite plans was 76.9 ± 16.6%, and the average gamma value across the composite plans was 0.67 ± 0.23. After correction, 20/20 composite plan fields passed the QA criteria (80/80 individual fields); the average gamma passing rate for composite plans was 99.2 ± 1.4%, the average gamma value across the composite plans was 0.33 ± 0.90. A measure of plan complexity, the average leaf pair opening could be correlated to the gamma analysis results for the uncorrected plans but not for the corrected plans.

Extraction optimization for the antioxidants from Nigella sativa seeds using response surface methodology

Although many studies have explored the bioactive compound content of Nigella sativa (black seed – BS) essential oil, data on the phenolic compound content in the extracts of Nigella sativa seeds gives inconclusive results [1–3]. In this study, response surface methodology (RSM) with a central composite plan (CCP) was used for the experimental design and identification of the optimal conditions for maximizing the phenolic content and the antioxidant activity of BS extract. The independent variables were as followed: temperature (22.9–67.1ºC), time (31.7–208.2 min), and methanol concentration in water (5.9–94.1% v/v). Different response variables (total polyphenols – TPC, total flavonoids – TFC and the antioxidant activity – DPPH and TEAC) required different optimal conditions to maximize them. The multi-response optimization was performed to determine the extraction conditions, which would simultaneously ensure the highest phenolic content and the antioxidant activity. The optimal conditions derived from the multi-response desirability function were as followed: 120 min, 56 °C and 50% methanol, giving the TPC = 7.05 mg/g, TFC = 3.05 mg/g, DPPH = 9.04 µmol/g and TEAC = 33.24 µmol/g (with desirability function coefficient = 0.83). Solvent concentration was established as a crucial parameter for the extraction of antioxidants from BS. A quercetin derivative and two derivatives of kaempferol were determined by HPLC (high performance liquid chromatography) analysis of the BS extract at the optimal conditions. The accuracy of the models for all response variables was confirmed by a high correlation coefficient (r = 0.99) between the experimental values and those predicted under optimal conditions.

Human remains in archaeology. Excavation, recording and analysis of data: the funerary context of San Severo in Classe

Funerary archaeology reveals burial practices and the ways in which such mortuary practices can express social identities. The integration of archaeological and anthropological evidence can offer significant data regarding burials. The study of the cemeteries of San Severo at Classe (Ravernna) is being carried out using this integrated approach. All phases of the site of San Severo are characterised by burials and this funerary practice changed and developed, reflecting the life of the basilica and the monastery. All information regarding the characteristics of the layers, the phases and activities of members is entered in the GIS platform, so composite plans can be automatically generated.

Repeated Stereotactic Body Radiotherapy for Lung Malignancies: Toxicity Can Be Reduced by Sparing Lung Irradiation.

Evidence on the use of repeated stereotactic body radiotherapy (SBRT) is limited. We investigated the efficacy of repeated SBRT and predictors of lung toxicity. We reviewed 20 patients (27 lesions) with primary or metastatic lung cancer who underwent repeated SBRT with CyberKnife® We generated a composite plan for dosimetric analysis based on equivalent doses in 2.0-Gy fractions (α/β=3). Predictors of Grade 2+ radiation pneumonitis (RP) were examined. The median follow-up duration was 18.0 months. The 1-year and 2-year local control were both 95.2%. Five patients (25%) developed Grade 2+ RP, including a Grade 5 RP. The Grade 2+ RP group showed higher composite mean lung dose (MLD) and lower lung volumes spared from 5-20 Gy (VS5-VS20). Repeated SBRT with CyberKnife® showed favorable local control, but a high rate of Grade 2+ RP. Accumulated MLD and VS5-VS20 may predict RP.