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This paper discusses the evolution of the microstructure during grain growth and recrystallisation, modelled using the Monte Carlo technique. The properties of alloys and metals subjected to plastic deformation and annealing are significantly influenced by the grain growth and recrystallisation processes. Modelling the recrystallisation process enables the simulation of various driving forces at a fundamental level by defining energy conditions for each individual element. The calculations facilitate the observation of microstructural evolution and the generation of structures consistent with any set of postulates, allowing both the dynamics and the physical processes of grain growth and recrystallisation to be simulated. The paper describes a recrystallisation model based on a two-dimensional array containing 40 000 elements. Each element in the array is assigned a number symbolising the orientation of the grain in which the given element is embedded, along with a value of the free energy of the grain boundary. The internal energy for a given grain is also specified. Four types of nucleation have been modelled. Based on the results obtained, the Monte Carlo technique is considered to be an effective tool for modelling recrystallisation processes, allowing the introduction of many different driving forces. The model presented in the work enables the simulation of the nature of local energy conditions and dynamics. [ABSTRACT FROM AUTHOR]

The phenomenon of primary recrystallization in metallic materials is a complex process that involves nucleation and growth of new grains from the deformed microstructure during post-deformation annealing heat treatment. In this study, we compare the experimental and numerical simulation results of primary recrystallization in metallic materials. The experimental tests were carried out on ARMCO iron samples extruded to 10, 20, and 30% of deformation degree and annealed at 973 K for 300 s. Microsections of the deformed and annealed specimens were analyzed using a metallographic microscope and Joyce-Loebl image analyzer. The numerical simulations were performed using a Monte Carlo algorithm to model the primary recrystallization of variable nucleation rate. On the basis of the classification given by Christian, four types of nucleation were simulated: site-saturated nucleation, constant nucleation rate, increasing nucleation rate, and decreasing nucleation rate, with different magnitudes of stored energy. Our results show that the decreasing nucleation rate model best fits the experimental data. The comparison between the experimental and numerical simulation results provides insights into the nucleation and growth of new grains during primary recrystallization in metallic materials. [ABSTRACT FROM AUTHOR]

The paper presents the application of a three-phase induction motor as a sensor measuring the force of the electromagnetic field connection between the engine and produced sheet steel. The force interaction between the engine and the manufactured sheet metal treated as a treadmill for a linear motor may be an indicator of damage to the material. Detection of places where the sheet does not meet the quality requirements may be very useful in the production process. FEM calculations were performed in the ANSYS MAXWELL environment. The results suggest the possibility of using this type of construction to test the quality of produced materials. The computational results and their analysis are presented in this article.

This article emphasizes the significance of understanding the actual thermal properties of thermal insulation materials, which are crucial for avoiding errors in building design and estimating heat losses within the energy balance. The aim of this study was to analyse the thermal parameters of selected thermal insulation materials, particularly in the context of their stability after a period of storage under specific conditions. The materials chosen for this study include commonly used construction insulations such as polystyrene and mineral wool, as well as modern options like rigid foam composites. Experimental studies were conducted, including the determination of the thermal conductivity coefficient λ , as well as numerical analyses and analytical calculations of heat flow through a double-layer external wall with a window. The numerical analyses were performed using the TRISCO software version 12.0w, based on the finite element method (FEM). A macrostructural analysis of the investigated materials was also performed. The findings indicated that improper storage conditions adversely affect the thermal properties of insulation materials. Specifically, storing materials outdoors led to a deterioration in insulating properties, with an average reduction of about 4% for the standard materials and as much as 19% for the tested composite material. Insufficient understanding of the true thermal properties of insulation materials can result in incorrect insulation layer thickness, degrading the fundamental thermal parameters of external walls. This, in turn, increases heat loss through major building surfaces, raises heating costs, and indirectly contributes to greenhouse gas emissions.

Objectives: Radiotherapy in patients with sinonasal mucosal melanoma (SNMM) was given as alternative treatment to surgery in cases with advanced, inoperable tumors or those not eligible for surgery. We presented the outcomes for patients with SNMM treated with radiotherapy alone., Material and Methods: The retrospective review of 6 consecutive SNMM (nasal cavity - 4 pts. and paranasal sinus - 2 pts.) patients (3 males and 3 females at mean age 64 years) treated between 2008 and 2016 was presented. The stage of disease was: T3 (1 pt.), T4a (3 pts.), T4b (2 pts.); with N0 and M0 in all patients. All patients underwent definitive primary photon radiotherapy (IMRT) alone; dose 66-72 Gy was delivered in 22-24 fractions given in 5 fractions (3 Gy) a week., Results: The complete remission was observed in all our patients but only one patient survived 5 years without disease. Five patients died due to multiple distant metastases; two of those patients developed associated local recurrence 7-8 months after radiotherapy., Conclusion: SNMM has a poor prognosis due to its high metastatic potential. Based on our numerically small report and data from literature we concluded that primary radiotherapy alone assured complete remission and even 5-year disease-free survival in only a few individual patients.

The prognosis for patients with melanoma who have brain metastases is poor, a median survival does not exceed 4-6 months. There are no uniform standards of treatment for patients with melanoma brain metastases (MBMs). The most preferred treatment approaches include local therapy - surgical resection and/or stereotactic radiosurgery (SRS). The role of whole brain radiotherapy (WBRT) as an adjuvant to local therapy is controversial. WBRT remains a palliative approach for those patients who have multiple MBMs with contraindications for surgery or SRS, or/and poor performance status, or/and very widespread extracranial metastases. Corticosteroids have been used in palliative treatment of MBMs as relief from symptoms related to intracranial pressure and edema. In recent years, the development of new systemic therapeutic strategies has been observed. Various modalities of systemic treatment include chemotherapy, immunotherapy and targeted therapy. Also, multimodality management in different combinations is a common strategy. Decisions regarding the use of specific treatment modalities are dependent on patient's performance status, and the extent of both intracranial and extracranial disease. This review summarizes current treatment options, indications and outcomes in patients with brain metastases from melanoma.

In the systemic treatment of brain metastases from non-small cell lung cancer (BMF-NSCLC) chemo- and targeted therapy are used. Response rates after platinum-based chemotherapy, range from 23% to 45%. Development of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs): gefitinib or erlotinib, was an improvement in treatment of advanced NSCLC patients. EGFR mutations are present in 10-25% of NSCLC (mostly adenocarcinoma), and up to 55% in never-smoking women of East Asian descent. In the non-selected group of patients with BMF-NSCLC, the overall response rates after gefitinib or erlotinib treatment range from 10% to 38%, and the duration of response ranges from 9 to 13.5 months. In the case of present activating EGFR mutation, the response rate after EGRF-TKIs is greater than 50%, and in selected groups (adenocarcinoma, patients of Asian descent, never-smokers, asymptomatic BMF-NSCLC) even 70%. Gefitinib or erlotinib treatment improves survival of BMF-NSCLC patients with EGFR mutation in comparison to cases without the presence of this mutation. There is no data on the activity of the anti-EML4-ALK agent crizotinib. Bevacizumab, recombinant humanised monoclonal antibody anti-VEGF, in the treatment of advanced non-squamous NSCLC patients is a subject of intense research. Data from a clinical trial enrolling patients with pretreated or occult BMF-NSCLC proved that the addition of bevacizumab to various chemotherapy agents or erlotinib is a safe and efficient treatment, associated with a low incidence of CSN haemorrhages. However, the efficacy and safety of bevacizumab used for therapeutic intent, regarding active brain metastases is unknown., Competing Interests: The authors declare no conflict of interest.

This article presents methods and results of surgery and radiotherapy of brain metastases from non-small cell lung cancer (BMF-NSCLC). Patients with single BMF-NSCLC, with Karnofsky score ≥ 70 and controlled extracranial disease are the best candidates for surgery. Stereotactic radiosurgery (SRS) is recommended in patients with 1-3 BMF-NSCLC below 3-3.5 cm, with minor neurological symptoms, located in parts of the brain not accessible to surgery, with controlled extracranial disease. Whole brain radiotherapy (WBRT) following SRS reduces the risk of local relapse; in selected patients median survival reaches more than 10 months. Whole brain radiotherapy alone is a treatment in patients with multiple metastases, poor performance status, uncontrolled extracranial disease, disqualified from surgery or SRS with median survival 3 to 6 months. There is no doubt that there are patients with BMF-NSCLC who should receive only the best supportive care. There is a debate in the literature on how to select these patients., Competing Interests: The authors declare no conflict of interest.

This article presents methods and results of surgical treatment and radiation therapy of brain metastases in breast cancer patients (brain metastases from breast cancer BMF-BC). Based on the literature data, it was shown that patients with single BMF-BC, aged less than 65 years, with Karnofsky score (KPS) of 70 or more and with cured or controlled extracranial disease are the best candidates to surgical treatment. Irrespective of the extracranial disease control status, there are indications for surgery in patients with symptomatic mass effect (tumour diameter larger than 3 cm) and patients with obstructive hydrocephalus from their BMF-BC. Stereotactic radiosurgery (SRS) has some advantages over surgery, with similar effectiveness: it may be used in the treatment of lesions inaccessible to surgery, the number of lesion is not a limiting factor if each lesion is small (< 3) and adequate doses can be delivered, it is not contraindicated in patients with active extracranial disease, it does not interfere with ongoing systemic treatment, and it does not require general anaesthesia or hospitalisation. A disadvantage of SRS, as compared to whole brain radiotherapy (WBRT), in patients with BMF-BC is the possibility of subsequent development of new lesion in the non-irradiated field. Thus the majority of the BMF-BC patients are not good candidates to surgery or SRS; WBRT alone or combined with a systemic treatment still plays a major role in the treatment of these patients.

Unlabelled: Contrast-enhanced spectral mammography (CESM) is a novel technique used for detection of tumour vascularity by imaging the moment in which contrast, delivered to the lesion by blood vessels, leaks out of them, and flows out through lymphatic vessels. In our study, we included 174 women for whom spectral mammography was performed for diagnostic purposes. The relationship between enhancement in CESM and blood vessel density (BVD), lymphatic vessel density (LVD) or the percentage of fields with at least one lymphatic vessel (distribution of podoplanin-positive vessels - DPV) and other related parameters was assessed in 55 cases. BVD, LVD and DPV were assessed immunohistochemically, applying podoplanin and CD31/CD34 as markers of lymphatic and blood vessels, respectively. The sensitivity (in detection of malignant lesions) of CESM was 100%, while its specificity - 39%. We found a significant positive correlation between the intensity of enhancement in CESM and BVD (p = 0.007, r = 0.357) and a negative correlation between the intensity of enhancement in CESM and DPV (p = 0.003, r = -0.390). Lesions with the highest enhancement in CESM showed a high number of blood vessels and a low number of lymphatics., Conclusions: 1) CESM is a method characterized by high sensitivity and acceptable specificity; 2) the correlation between CESM results and blood/lymphatic vessel density confirms its utility in detection of tissue angiogenesis and/or lymphangiogenesis.

Optimal treatment for patients with only local prostate cancer recurrence after external beam radiation therapy (EBRT) failure remains unclear. Possible curative treatments are radical prostatectomy, cryosurgery, and brachytherapy. Several single institution series proved that high-dose-rate brachytherapy (HDRBT) and pulsed-dose-rate brachytherapy (PDRBT) are reasonable options for this group of patients with acceptable levels of genitourinary and gastrointestinal toxicity. A standard dose prescription and scheme have not been established yet, and the literature presents a wide range of fractionation protocols. Furthermore, hyperthermia has shown the potential to enhance the efficacy of re-irradiation. Consequently, a prospective trial is urgently needed to attain clear structured prospective data regarding the efficacy of salvage brachytherapy with adjuvant hyperthermia for locally recurrent prostate cancer. The purpose of this report is to introduce a new prospective phase II trial that would meet this need. The primary aim of this prospective phase II study combining Iridium-192 brachytherapy with interstitial hyperthermia (IHT) is to analyze toxicity of the combined treatment; a secondary aim is to define the efficacy (bNED, DFS, OS) of salvage brachytherapy. The dose prescribed to PTV will be 30 Gy in 3 fractions for HDRBT, and 60 Gy in 2 fractions for PDRBT. During IHT, the prostate will be heated to the range of 40-47°C for 60 minutes prior to brachytherapy dose delivery. The protocol plans for treatment of 77 patients.

Aim of the Study: Aim of the study is to evaluate the results of postoperative radiotherapy of paragangliomas, prognostic factors and causes of treatment failure., Material and Methods: Forty-four patients (39 females and 5 males) aged 20 to 74 years were treated for paraganglioma between 1970 and 2010 at the Centre of Oncology in Kraków. Patient survival probability was estimated with the Kaplan-Meier method. Log-rank tests and Cox proportional hazard model were used in univariate and multivariate analysis, respectively., Results: The most common locations of paragangliomas were the following: the ear, carotid body and internal jugular vein bulb. Forty (91%) out of them were benign and 4 - malignant. All patients underwent surgery followed by adjuvant radiotherapy. The delivered dose ranged from 50 to 72 Gy, the mean dose was 60 Gy. Five-year overall survival was 84%. Five-year relapse-free survival was 84%, either. The multivariate analysis has shown that the dose in an independent prognostic factor for the overall survival. The univariate analysis has shown significantly higher 5-year overall survival in patients who received a dose of 60 Gy or higher - 92% vs. 70% in patients who received a dose lower than 60 Gy., Conclusions: Postoperative radiotherapy with doses higher than 60 Gy in patients with paragangliomas is associated with longer overall survival.

Purpose: The aim of this study is to assess results of treatment, factors influencing prognosis with regard to causes of failure and treatment tolerance in patients with thymoma., Material and Methods: Between 1966 and 2006, 63 patients with thymoma had been treated at the Centre of Oncology in Krakow. Patients were treated by means of different treatment modalities: surgery followed by radiotherapy (52%), radiotherapy alone (13%), chemoradiotherapy alone (15%), surgery followed by chemoradiotherapy (5%), surgery alone (5%) and others., Results: The 10-year locoregional recurrence-free survival (LRRFS) was 79%, disease free survival (DFS) was 57% and overall survival (OS) was 57%. Masaoka stage was the only independent prognostic factor for LRRFS. Masaoka stage and method of radiotherapy delivery (higher photon energies), were independent prognostic factors for OS. For DFS, the independent prognostic factors were age, type of treatment (favoured surgery followed by radiotherapy or chemoradiotherapy), Masaoka stage and year of start of treatment. Most common reactions were lung fibrosis in 36% of patients (mainly asymptomatic in most patients), pneumonitis (9%) and oesophagitis (4%)., Conclusions: Surgery combined with radiotherapy and chemoradiotherapy and modern radiotherapy techniques are correlated with improvement of survival in patients with early stage thymoma.

Between 1992 and 1999 at the Oncology Centre in Cracow 138 NSCLC patients after complete resection of the tumour with mediastinal/hilar node involvement were included in the prospective clinical trial. The analysis of the results did not show any improvement of survival in the postoperatively irradiated group. Three-year survival rates with no symptoms of disease in postoperative radiotherapy patients compared to surgery alone group were 30% and 29% respectively. In this study adjuvant radiotherapy significantly improved local recurrence rate from 28% in surgery only group to 9% in postoperatively treated patients.

In a retrospective analysis of 150 incompletely resected NSCLC patients treated with adjuvant external beam radiotherapy 32 (21.3%) survived 3 years with no symptoms of disease. Ipsilateral mediastinal/hilar lymph node involvement and macroscopic incomplete surgery were the prognostic factors that unfavourably influenced survival in Cox's proportional hazards model. Postoperative external beam radiotherapy was the efficient adjuvant treatment method in microscopically incompletely resected NSCLC, predominantly with no nodes involvement, but had no benefit in those with macroscopic incomplete surgery.