Surgical treatment of intradiploic epidermoid cyst treated as depression

Introduction. Extradural intradiploic epidermoid cysts are rare, representing less than 0.25% of all primary intracranial tumors. They can be neurologically silent and can only present psychiatric symptoms like depression, cognitive or personality changes. Case Outline. A 68-year-old male with two year long history of depressive mood, lack of motivation, helplessness, hopelessness and poor response to antidepressive drug therapy was described. CT scan showed a well-defined mass in the parietal scalp with destruction of the scull. He underwent intracranial tumor resection. Surgical resection and cranioplasty were performed. Pathology confirmed intradiploic epidermoid cyst. Conclusion. Total removal of these cysts and repeated washing of the cavity with 0.9 % saline may prevent recurrence and aseptic meningitis and may improve mental state of the patient. We also emphasize the need for neuroimaging studies in a patient with atypical changes in mental status, even without neurological signs or symptoms

Design of Custom Made Prosthesis of the Hip

Replacement of a natural hip joint with an artificial is one of the most commonly used surgical procedures in orthopaedic surgery. This paper describes the methodology of the hip joint prosthesis design, which presents the foundation for the automation of all stages of the development of custom-made prostheses. A general mathematical model based mostly on B-spline surfaces is used in order to define the prosthesis geometry. In order to verify the method, a software solution was developed and used for designing prostheses based on ten diagnostic images obtained by various methods. The results of the analysis of the ten designed prostheses, out of which five manufactured, show that deviations from the desired values are less than the errors caused by diagnostic imaging

SUSTAINABILITY OF POST-SOCIALIST URBAN DESIGN TREATMENT OF PUBLIC OPEN SPACES IN MULTI-FAMILY HOUSING AREAS: CASE STUDY OF NIS, SERBIA

This research focuses on the treatment of public open spaces (POS) in multi-family housing areas in post-socialist Central and Eastern European (CEE) countries. The aim is to evaluate their quality and sustainability and to identify all important impact factors influencing their properties. A case study was conducted on a representative sample of four multi-family housing sites in Nis, Serbia. Determining the interconnection between urban planning parameters and the realized quality of POS is one of the primary objectives that could lead to forming recommendations for future multi-family housing development, including more usable and sustainable POS in the current social and economic context. The models for improvement of POS quality and sustainability are defined as a research result

PSYCHOLOGICAL EFFECTS OF INDOOR AIR POLLUTION

Office buildings need to provide clean, cozy and comfortable working environment with good indoor air quality in order to create favorable conditions for psychological and physical functioning. Most people are not satisfied with the quality of air in an enclosed office space, which is one of the factors that affect people’s work, productivity and stress levels. Indoor air pollution reduces person's ability to respond to the demands of the environment, which often leads to fatigue, malaise, anxiety, headaches, mental confusion, reduced mental and physical performance, as well as irritation of the eyes and throat, coughing and wheezing. The outcomes of exposure to air pollution is largely mediated by the intervening perceptive and cognitive processes that shape behavioral and health responses to stressors. Longer exposure to pollutants can lead to behavioral and mood changes, personality changes, impaired memory, slower motor responses and other functional deviations. Poor indoor air quality can cause diseases such as "sick building syndrome" mass psychogenic illness, and environmental diseases caused by the influence of environmental stress

Experimental analysis and FEM modelling of a cutting tool vibrations

Presented in this paper is a comparative analysis of vibrations, measured during machining process and modelled by FEM. Moreover, microscopic structure of chip cross section was analyzed in order to establish the frequency of lamellae generation and its influence on the total level of vibrations of the cutting tool. Based on the results thus obtained, a method was proposed which allows determination of tool wear degree through separation of reliable indicators from the high-frequency spectrum of the measured vibration signals. This investigation showed that the change of chip segmentation frequency significantly influences the output vibration signal within the high-frequency spectrum, and is a function of tool wear degree

Numerical study of heat transfer during nucleate pool boiling

U ovom radu je izvršena trodimenzionalna numerička simulacija atmosferskog, zasićenog ključanja u velikoj zapremini. Primenjeni matematički model i numerička metoda omogućavaju potpuni prikaz ponašanja dvofazne mešavine na grejnoj površini kao i predviđanje slobodnog nivoa tečnosti. Ovde prikazano trodimenzionalno istraživanje je sprovedeno kako bi se uzela u obzir konvektivna razmena toplote na grejnoj površini kao i prostorni efekti generacije pare i dvofaznog toka, kao što su disprzija faza u dvofaznoj mešavini. Predstavljeni su rezultati simulacije nakon kratkog vremenskog perioda od početka zagrevanja i formiranja mehurova na grejnoj površini. Prikazani su popunjenost grejne površine vodom i parcijalna okvašenost površine za niže vrednosti toplotnog fluksa. Diskutovan je uticaj gustine nukleacije i vremena zadržavanja mehurova na grejnom zidu na dinamiku ključanja. Takođe je proučen uticaj intenziteta toplotnog fluksa na dinamiku ključanja u velikoj zapremini. Primenjeni numerički metod i matematički model je pokazao ispravnost, omogućavajući stabilan proračun za širok opseg primenjenih parametara pri modeliranju.In this paper three-dimensional numerical simulation of the atmospheric saturated pool boiling was performed. The applied modelling and numerical methods enable full representation of the two-phase mixture behaviour on the heating surface with the inclusion of the swell level prediction. The three-dimensional investigation presented here was performed in order to take into account a convective heat transfer on the heated surface, as well as spatial effects of the vapour generation and a two phase flow such as phase dispersion within the two-phase mixture. The results are presented for a short period of time after the initiation of the heat supply and vapor generation on the heating surface. The replenishment of the heating surface with water and partial surface wetting for lower heat fluxes is shown. The influence of the density of nucleation sites and the bubble residence time on the wall on the pool boiling dynamics is discussed. Also, the influence of the heat flux intensity on the pool boiling dynamics is investigated. The applied numerical and modelling method showed robustness by allowing stable calculations for wide ranges of applied modelling boiling parameters

Action of pulsed lasers on titanium target: surface effects

The interaction of lasers with metals has been studied for decades, and has been especially intensified lately, due to the development of new, efficient pulsed lasers. Titanium has a number of excellent properties, making it applicable in various modern technologies. Treatment and processing of titanium is possible with various techniques, and the application of lasers gives a special quality, such as high precision machining or obtaining specific structures on the surface which cannot be generated by other methods. During our research, surface processing of titanium was conducted by various pulsed lasers: nanosecond CO2 laser, picosecond Nd:YAG laser and femtosecond Ti: sapphire laser. In order to find the optimal conditions for surface modification of titanium, the influence of different laser parameters (wavelength, pulse duration, pulse energy, etc.), as well as the influence of the ambient, was examined. The titanium samples were irradiated in different environments, ie. in air, oxygen, nitrogen, carbon dioxide, helium and in vacuum, which affected the chemical composition and morphology of the target surface.SPIG 2022 : 31st Summer School and International Symposium on the Physics of Ionized Gases : Contributed papers and abstracts of invited lectures, topical invited lectures and progress reports; September 5-9,2022, Belgrad

Numerical modeling of the edentulous mandible with a complete denture using multiblock method

In this paper, finite element model of edentulous lower jaw (mandible) is generated, as well as the model of support layer and complete denture using various software. The aim of this study was to produce 3D digital mandibular complete denture, mucosa, and supporting bone models using reverse engineering and evaluate effect of mucosa thickness and resiliency on stress distribution of complete denture. In this study we used a model of mandibular complete denture and 5 mm thickness of mucosa (which represent the resiliences soft). The influence of resilient mucous membranes layer thickness is analysed by assigning loads to simulate the force due to chewing on the lower right and left central incisor and lower right and left first molar. Based on the numerical results, we conclude that the maximum stress values were concentrated in cortical bone

Aromatička svojstva potpunih benzenoidnih ugljikovodika

We consider a family of structurally closely related fully-benzenoid hydrocarbons of increasing number of fused benzene rings. Local and global aromatic properties of such molecules are investigated with a particular interest in investigating the role of the finite size of such molecules in modelling the high-polymer or even graphite. An interesting alternation of local properties for benzene rings in a similar environment was observed.Razmatrana je skupina strukturno vrlo sličnih potpunih benzenoidnih ugljikovodika. Studirana su lokalna i globalna svojstva ovih molekula, a naročita je pažnja posvećena ulozi konačne veličine studiranih molekula u modeliranju benzenoidnih polimera ili čak grafita. Opažena je interesantna pojava da lokalna svojstva benzenskih prstenova alterniraju u sličnom okolišu, iako razlike u veličinama opadaju rastom veličine molekule