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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. [ABSTRACT FROM AUTHOR]

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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.

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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The occurrence of brain metastasis from colorectal carcinoma (BM-CRC) ranges from 0.06-4%. Their rare occurrence makes various issues associated with these lesions controversial. Based on the literature data, this article presents population characteristics and clinical features of BM-CRC, their treatment methods and prognostic factors in these patients. It has been demonstrated that BM-CRC is mainly detected in patients with advanced CRC (III° and IV°) and is usually preceded by lung and liver metastases. The authors report population- based characteristics of BM-CRC, i.e. greater frequency in males and mean patient age of 51-73 years, and clinical features, such as supratentorial location in over a half of cases, the occurrence of a single BM-CRC in a half of patients and median size of 24-33 mm. Moreover, the authors discuss treatment methods in BM-CRC, including surgery (stereotactic radiosurgery, SRS), whole brain radiotherapy (WBRT) and systemic treatment, applied either alone or in combination. The observation made in literature reports that aggressive surgery or SRS prolong survival and improve quality of life, particularly when combined with WBRT, has been confirmed. WBRT alone remains the mainstay of palliative BM-CRC treatment. It is also used in patients ineligible for surgery or SRS, with multiple BM-CRC, with poor performance status and with uncontrolled extracranial disease. Patients with BM-CRC present poor prognosis. Median overall survival (OS), as presented in the references from 2014-2016, ranges from 2 to 7 months. Higher OS rates are reported in selected groups of patients, mainly those primarily treated with surgery or SRS (5-14 months). The main positive prognostic factors in patients with BM-CRC are: the Karnofsky Performance Score (KPS) ≥70, BM-CRC number not greater than 2 and no active extracranial CRC. [ABSTRACT FROM AUTHOR]

Surgery, with an attempt to remove a tumor within a margin of healthy tissues, is the preferred primary treatment of head and neck mucosal melanoma (HNMM). Despite radical surgery, the tumor tends to recur locally and give regional or distant metastases in many patients. Classical radical surgery is usually applied for sinonasal mucosal melanoma. Endoscopy is an alternative to classical surgery, but can be used in specific clinical cases and when appropriate criteria are met. The basic treatment method in patients with oral mucosal melanoma is ablation of various degrees depending on tumor location and local advancement. The presence of metastases from HNMM in the regional lymph nodes is an indication to lymphadenectomy. Experts from the National Comprehensive Cancer Network emphasize the role of prophylactic lymphadenectomy in oral mucosal melanoma but see no reason for its application in sinonasal mucosal melanoma. HNMM patients have not been and still are not frequently included in clinical trials investigating cutaneous melanoma. Adjuvant systemic treatment of patients operated for HNMM raises many doubts. Patients with a generalized disease and/or inoperable locally advanced tumor frequently receive systemic treatment similar to that applied for cutaneous melanoma. However, a different clinical picture, histopathological features and significant molecular differences suggest that a different systemic treatment would be more adequate. To date, none systemic therapy has been found effective in this group of patients. New drugs for molecular targeted therapy (vemurafenib, dabrafenib, imatinib) and immunotherapy (ipilimumab, pembrolizumab, nivolumab) are promising in terms of effective treatment of patients with generalized and/or inoperable HNMM. Therapy outcomes are poor and much worse when compared to cutaneous melanoma patients. Five-year overall survival ranges from 20% to 40%. [ABSTRACT FROM AUTHOR]

Head and neck mucosal melanoma (HNMM) accounts for merely 0.03% of all malignant neoplasms and 0.7-1% of all melanomas. Its rare occurrence makes various issues associated with this neoplasm controversial. The first part of the publication discusses HNMM epidemiology, as reported in the literature, with particular emphasis on their location in the oral cavity, nasal cavity and paranasal sinuses. Differences in the incidence between populations, which indicate that HNMM is much more common in Asian people, are underlined. It is shown that the pathogenesis of HNMM is basically unknown, and that the only suspected risk factor is formaldehyde exposure. Subsequently, population-based HNMM features are presented, i.e. similar incidence in women and men as well as median age of 60-65 years. Moreover, the most common clinical signs are discussed, i.e.: obstruction and watery or purulent nasal discharge, persistent and progressive epistaxis, facial pain, watering eye, vision disorders etc. in patients with sinonasal mucosal melanoma; and flat pigmented or nodular, frequently exophytic and ulcerated lesions in patients with oral mucosal melanoma. The risk of lymph node invasion was evaluated at 10-20% and the risk of distant metastases was estimated at 5-10% at the time of the diagnosis based on literature data. It is mentioned that the diagnosis of mucosal melanoma is mainly based on results of microscopic assessment and detection of three markers: S100, HMB-45 and Mela-A in the tumor tissue. It is concluded that the most frequent molecular anomalies typical of HNMM are NRAS and c-KIT mutations. Finally, the current HNMM staging system (UICC 2010) and the principles of the diagnostic workup of this disease are presented. [ABSTRACT FROM AUTHOR]

Copyright of Onkologia i Radioterapia is the property of Wydawnictwo SALVE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Primary surgery, with an attempt to remove a tumor within the margin of healthy tissues, is the treatment of choice in head and neck mucosal melanoma (HNMM). Unfortunately, radical procedures are frequently difficult, mainly due to the anatomical conditions in the operated region associated with close proximity of numerous critical structures with important functions. It must be underlined that HNMM is characterized by particularly frequent local recurrences. The analysis of the literature shows that a vast majority of authors prove in a relatively unambiguous way that the usage of postoperative radiotherapy (PRT) reduces the occurrence of locoregional recurrences compared with surgery alone. Unfortunately, PRT does not affect remote survival outcomes, which is mainly associated with the tendency of HNMM to disseminate early and massively. Commonly acknowledged criteria for PRT include failure to obtain macro- or microscopic radicality of surgery. Other indications, as suggested by certain authors, encompass patients in whom the procedure was radical with a relatively small microscopic margin. Currently preferred total dose of radiation is 60-70 Gy administered in the period of 6-7 weeks according to a conventional fractionation system, i.e. 1.8-2.0 Gy delivered once daily. Primary radiation therapy is used in patients with advanced neoplasm or those who are not eligible for surgery due to poor performance status; this group also includes patients who do not consent to surgical treatment. Primary radiotherapy gives a chance not only for a good palliative effect, but also, in certain patients, for complete local control. The condition is the application of, for example, intensity-modulated radiotherapy (IMRT) and administration of an adequately high dose of biological radiation, usually using hypofractionation. The fact that proton beam therapy or irradiation with carbon ions gives hope for a marked improvement in local curability in this group of patients is incontestable. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The continuum material has been modeled employing a 2D discrete lattice containing 200x200 elements. Four different nucleation models, i.e. site saturation, continuous, increasing and decreasing nucleation rate were compared. The sigmoidal time dependence of recrystallized volume fraction observed in the simulation is often emphasized in the literature and finds its justification in the experiment. The Avrami exponent n = 2 is properly reproduced by the simulations. It has been shown that the model correctly responds to the change in the degree of stored energy H/J. [ABSTRACT FROM AUTHOR]

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.

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.

Purpose: The aim of the research was to evaluate of intraocular complications after proton beam therapy of choroidal melanomas, Material and Methods: A total 105 patients (48 female and 57 male) from Department of Ophthalmology and Ocular Oncology of University Hospital in Cracow, who received proton beam radiation due to choroidal melanoma were enrolled. The mean age was 52.3 years (51.8 y. in females, 52.6 y. in males). Total irradiation dose was 60 cGy and it was applied in 4 fractions per 15 cGy (on 4 consecutive days). We evaluated the incidence of complications classifying patients by age, tumor location, tumor thickness, longitudinal and transversal basal diameter and follow-up period, which ranged between 5 and 57 months., Results: Complications of intraocular irradiation were observed in 33 out of 105 treated patients. Retinopathy occurred in 18 cases, including 4 patients with macular edema. Neuropathy was confirmed in 8 patients, secondary glaucoma in 6 cases; we noted 9 cases of initial or progress existing cataract, 4 cases of dry eye syndrome and 1 patient with central retinal vein occlusion. A statistically significant positive correlation was demonstrated between the length of the follow-up period and the incidence of complications, which were more common and more severe with the longer follow-up period. There was no statistically significant correlation between the incidence of complications and patient’s age, tumor location, tumor thickness as well as longitudinal and transversal basal diameter., Conclusion: All forms of radiation therapy used in intraocular tumors are associated with some risk of complications; proton beam radiotherapy is not free of that risk, either.

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.

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.

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.