Modeling of Yb:YAG Laser Beam Caustics and Thermal Phenomena in Laser-Arc Hybrid Welding Process with Phase Transformations in the Solid State.

This paper focuses on the mathematical and numerical modeling of the electric arc + laser beam welding (HLAW) process using an innovative model of the Yb:YAG laser heat source. Laser energy distribution is measured experimentally using a UFF100 analyzer. The results of experimental research, including the beam profile and energetic characteristics of an electric arc, are used in the model. The laser beam description is based on geostatistical kriging interpolation, whereas the electric arc is modeled using Goldak's distribution. Hybrid heat source models are used in numerical algorithms to analyze physical phenomena occurring in the laser-arc hybrid welding process. Thermal phenomena with fluid flow in the fusion zone (FZ) are described by continuum conservation equations. The kinetics of phase transformations in the solid state are determined using Johnson-Mehl-Avrami (JMA) and Koistinen-Marburger (KM) equations. A continuous cooling transformation (CCT) diagram is determined using interpolation functions and experimental research. An experimental dilatometric analysis for the chosen cooling rates is performed to define the start and final temperatures as well as the start and final times of phase transformations. Computer simulations of butt-welding of S355 steel are executed to describe temperature and melted material velocity profiles. The predicted FZ and heat-affected zone (HAZ) are compared to cross-sections of hybrid welded joints, performed using different laser beam focusing. The obtained results confirm the significant influence of the power distribution of the heat source and the laser beam focusing point on the temperature distribution and the characteristic zones of the joint.

Potentially Lethal But Rarely Considered. Risk of Developing Refeeding Syndrome in Primary Oral Squamous Cell Carcinoma.

Presurgical preparation and postoperative care are cornerstones of all surgical procedures. Surgeons should be especially vigilant with malnourished cancer patients. Refeeding syn-drome (RFS) is a serious, potentially fatal complication of initiating appropriate nutrition in malnourished patients or after a period of starvation, although no standard precise definition has been proposed. The rarity of its une-quivocally life-threatening course means that its risk may be underestimated in clinical practice. The study's main goal was to assess the degree of malnutrition and the risk of RFS in the presurgical status of patients with oral cavity cancer and to identify risk factors for the occurrence of RFS. This single-center prospective observational study included patients diagnosed with oral squamous cell carcinoma. We investigated the relationship of RFS with age, BMI, features of the malignant tumor process selected internal medicine comorbidities, inflam-matory markers, renal and hepatic parameters, plasma levels of diverse electrolytes, and microelements were assessed. In the work, we utilized the National Institute for Health and Clinical Excellence (NICE) criteria. The study included 90 patients: 35 women and 55 men, aged 64.2±10.5. A robust statistical correlation at a significance level of p < 0.05 was demonstrated between advanced age, lower BMI, lymph node metastases, and a relatively low LDH as positive predictors of the onset of RFS and confirmed the high predictive value of the NRS-2002 scale. This paper seeks to call attention to RFS and identify critical issues that may be useful for its prevention.

Numerical Prediction of Strength of Socket Welded Pipes Taking into Account Computer Simulated Welding Stresses and Deformations.

The paper presents a numerical model based on the finite element method (FEM) to predict deformations and residual stresses in socket welding of different diameter stainless steel pipes made of X5CrNi18-10 steel. The next part of the paper concerns the determination of strength properties of a welded joint in terms of a shear test. A thermo-elastic-plastic numerical model is developed using Abaqus FEA software in order to determine the thermal and mechanical phenomena of the welded joint. This approach requires the implementation of moveable heat source power intensity distribution based on circumferentially moving Goldak's heat source model. This model is implemented in the additional DFLUX subroutine, written in Fortran programming language. The correctness of the assumed model of thermal phenomena is confirmed by examinations of the shape and size of the melted zone. The strength of the welded joint subjected to shear is verified by performing a compression test of welded pipes as well as computer simulations with validation of the computational model using the Dantec 3D image correlation system.

Oral cancer awareness among patients at 3 university hospitals in Poland and Germany: A survey research.

BACKGROUND: The epidemic of cancer (including oral cancer) is a growing public health and economic problem in the European societies. A high percentage of patients who come for the appropriate treatment are in the late stages of advancement, often with nodal and/or distant metastases. The literature on the public oral cancer awareness in Poland and Germany is limited. OBJECTIVES: To investigate the levels of public awareness about the early symptoms and risk factors of oral cancer, and to analyze the findings in the context of the socioeconomic profiles of the subjects. MATERIAL AND METHODS: The survey consisted of a 20-item questionnaire divided into 4 sections: socioeconomic and demographic factors, the awareness of oral cancer, symptoms of oral cancer, and its risk factors. It was distributed to 465 adult patients in Poland (Wroclaw and Lódz) and Germany (Dresden). RESULTS: The response rate was 97.6%. Most of the respondents (65.4%) had heard of oral cancer. The sources of information were mainly the traditional mass media and the Internet, with only 23.8% of the respondents indicating doctors as a source of information about oral cancer. What is worrying, only about 1/5 of the participants in each of the 3 centers had an oral cancer examination last year. The awareness of oral cancer correlated positively with the age of the respondents and negatively with the size of the place of residence. Education level had no significant impact on declared knowledge. CONCLUSIONS: The results of this survey do not only show unsatisfactory levels of patients' awareness of the risk factors and symptoms of oral cancer but also emphasize the need to improve the level of healthcare concerning this disease, including screening programs.

Information impact on synaptic arousal and formation of permanent memory trace.

Memory trace is an effect of temporary arousal (perception, experience, action) that causes a specific change in the nervous system. Memory allows to record and recall various information, thus enabling to learn new things. It is an extremely active and dynamic process. The influence of emotions on memory is obvious, largely determined by the close cooperation of the amygdala (responsible for emotions) and the hippocampus (memory processes).

The Influence of Welding Heat Source Inclination on the Melted Zone Shape, Deformations and Stress State of Laser Welded T-Joints.

The paper concerns the numerical analysis of the influence for three different of welding heat source inclinations on the weld pool shape and mechanical properties of the resulting joint. Numerical analysis is based on the experimental tests of single-side welding of two sheets made of X5CrNi18-10 stainless steel. The joint is made using a laser welding heat source. Experimental test was performed for one heating source inclination. As a part of the work metallographic tests are performed on which the quality of obtained joints are determined. Numerical calculations are executed in Abaqus FEA. The same geometrical model is assumed as in the experiment. Material model takes into account changing with temperature thermophysical properties of austenitic steel. Modeling of the motion of heating source is performed in additional subroutine. The welding source parameters are assumed in accordance with the welding process parameters. Numerical calculations were performed for three different inclinations of the source. One inclination is consistent with experimental studies. The performed numerical calculations allowed to determine the temperature field, shape of welding pool as well as deformations and stress state in welded joint. The obtained results are compared to results of the experiment.

A new family with spastic paraplegia type 51 and novel mutations in AP4E1.

BACKGROUND: Autosomal recessive mutations in the AP-4 (adaptor protein complex 4) complex subunit ϵ - 1 (AP-4E1) gene on chromosome 15q21.2 are known to cause spastic paraplegia 51 (SPG51). The exact phenotype of SPG51 remains poorly characterized, because only a few families have been reported as carriers of the mutation. In addition, a previous study identified an autosomal dominant mutation in the AP4E1 gene as being associated with persistent stuttering. The aim of the current study was to characterize the phenotype of a paediatric patient with an identified novel AP4E1 mutation presenting with significant psychomotor retardation, intellectual disability and paraplegia. METHODS: Magnetic resonance imaging was used to identify hypoplasia of the corpus callosum. The DNA sample was tested using multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (aCGH). In addition, next-generation sequencing (NGS) was performed using the patient's DNA, and Sanger sequencing was performed using that of his family members. RESULTS: The phenotype was identified to be associated with a novel pathogenic variant c.942_943 + 3delinsCC in the AP4E1 gene. The patient manifested severely delayed psychomotor development, impaired global physical development and general illness. Movement disorders were evident during the neonatal period. CONCLUSIONS: The present study identifies a previously unknown disease-inducing AP4E1 gene mutation.

Dental and Skeletal Changes after Transpalatal Distraction.

Maxillary constriction is a common skeletal craniofacial abnormality, and transverse maxillary deficiency affects 30% of patients receiving orthodontic and surgical treatment. The aim of the study was to analyse craniofacial skeletal changes in adults with maxillary constriction after transpalatal distraction. The study group consisted of 36 patients (16 women) aged 17 to 42 years (M = 27.1; SD = 7.8) with a known complete skeletal crossbite and who underwent transpalatal distraction procedure. The measurements were obtained on diagnostic models, and cephalometric PA radiograms were obtained at time points, i.e., before treatment (T1) and after the completion of active distraction (T2). The analysis of diagnostic models involving the arch width measurement at different levels demonstrated a significant increase in L1, L2, L3, L4, L5, and L6 dimensions after transpalatal distraction. The largest width increase (9.5 mm) was observed for the L3 dimension (the intercanine distance). The analysis of frontal cephalograms displayed a significant increase in W1, W2, and W3 dimensions after transpalatal distraction. The largest width increase (4.9 mm) was observed for the W1 dimension at the level of the alveolar process of the maxilla. Transpalatal distraction is an effective treatment for transverse maxillary deficiency after the end of bone growth. The expansion observed on diagnostic models is close to a parallel segment shift mechanism, with a mild tendency towards a larger opening anteriorly. The maxillary segment rotation pattern analysed based on the frontal cephalograms is close to a hand fan unfolding with the rotation point at the frontonasal suture.

Cell reactions and immune responses to photodynamic therapy in oncology.

Photodynamic therapy (PDT) is a noninvasive, highly selective method for the treatment of diseases characterized by uncontrolled cell proliferation. It was clinically approved more than 30 years ago. PDT involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species (ROS) upon irradiation with visible or near-infrared (NIR) light. ROS induce destruction of target cells and damage of tumor-associated vasculature and activate an antitumor immune response, leading to tumor regression. The execution of this process is attained by different mechanisms, including host immune responses and activation of cell death pathways: apoptosis and necrosis.

Atypical lipomatous tumor of the cheek - a case report.

Liposarcoma is the most common soft tissue malignant tumor. It mostly arises in the subcutaneous tissue of shoulders, limbs and neck, and retroperitoneal space, but head occurrence is very rare. Atypical lipomatous tumor (ALT) is a well-differentiated liposarcoma (WDLPS) and constitutes 40-45% of all liposarcoma cases. A case of 57-year-old woman with a tumor of the left cheek, causing a discreet face asymmetry is presented. The tumor was soft and caused no tenderness. The patient reported no previous injury of the region. Fine-needle aspiration biopsy (FNAB) revealed atypical cells suspected of liposarcoma. MR examination showed fascicles of adipose tissue, which made the left cheek prominent. The patient was operated under general anaesthesia. Adipose tissue of the left cheek was removed. Postoperative course was uneventful. The final histopathological diagnosis - was atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDLPS). The patient remains under laryngological care. No recurrence of the disease has been observed during the 5 years follow-up.

[Surgery treatment of salivary gland tumors]. / Leczenie chirurgiczne guzów nowotworowych slinianek.

INTRODUCTION: Tumors of parotid gland represent a diverse group of neoplasms with varied clinical behaviors. MATERIAL AND METHODS: The diagnostic methods and treatment of salivary gland tumors are presented in this paper. The authors describe the group of 44 patients with salivary gland tumors treated surgically in ENT Departament Laryngology of Medical University in Lódz. Enucleation, partial and total parotidectomy were performed. Neurosign 100 unit was used during parotidectomy to monitoring course of facial nerve. RESULTS: Tumor mixtus was a dominate type of tumors. Only three patients with malignant tumor had facial nerve paralysis after surgery. CONCLUSIONS: (1) The extent of the surgical procedure depends on histopathologic diagnosis. (2) Using of facial nerve monitoring during parotid surgery improves its outcomes.