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Background: Burnout is a special a state of physical or emotional exhaustion that also involves a sense of reduced accomplishment and loss of personal identity.Objectives: To evaluate the predictors of burnout among work staff in the seven private agencies for support and defense of persons and their property.Material and Method: We performed a multicentric cross-sectional study that involved representative sample of working staff from Agencies of Private Security in Central Serbia. Burnout was assessed using Maslach Burnout Inventory- (MBI)-Human Services Survey.Results: A total number of participants were 353 (330 men and 23 women). Measured level of burnout as assessed by high emotional exhaustion, high depersonalization, and low personal accomplishment was 66.3, 82.4, and 13.4%, respectively. We identified that female gender, younger age, shorter work experience, working in shifts, working 12 h a day and more than 8–12 h a day as well as dissatisfaction with working conditions. Work in shifts, working 12 h a day and more than 8–12 h a day and dissatisfied with dissatisfaction with working conditions significantly increase the risk of total burnout.Conclusion: Our results showed that significant predictors for the development of burnout syndrome were female gender, younger age, shorter work experience, working in shifts, as well as dissatisfaction with working conditions.

Improvements in the energetic efficiency of a building bear the greatest potential in terms of saving energy and reducing the emission of toxic gases. One of the most efficient energetic efficiency improvement measures is replacement of old coal boilers for central heating with new pellet boilers. The study presents the comparison between planned savings before replacement of boilers and realized savings after their replacement. The theoretical approach was based on the analysis of the energetic characteristics of this object in the investment planning stage by applying mathematical modeling. It was published as a part of the research paper “Revitalization of architectural objects by means of energy efficiency improvement: An economic case analysis” [1] . However, the decisions made in the phase of boilers replacement were different compared to the planned investment. Between theory and practice, this paper analyzes the difference between parameters envisaged in precalculations and those achieved later. Rational energy consumption and environmental protection are the crucial elements of energy policie, as well as the key elements of national growth and development. A great contribution to solving this crucial development problem would be made by accurate investment planning and its consistent implementation, thus establishing harmony between theory and practice.

Strongly influenced by the need for energy efficiency improvements, this research aims to help reduce energy consumption by applying effective energy measures. Improvements in a building's energy efficiency bear the greatest potential in terms of saving energy and reducing toxic gases emission. Three energy improvement measures have been suggested concerning “Karaburma” Elderly Care Facility in Belgrade: (1) the insulation of a thermal envelope, (2) the replacement of old coal boilers by new pellet boilers, and (3) the replacement of windows and doors. The object is a complex of nine blocks of buildings built in 1963. The analysis of the energy characteristics of this object has been carried out by applying mathematical modeling. The saved energy is able to pay back the investments within 11 years and 3 months, while simultaneously having a positive effect on the environment since coal is discarded as a fuel. The goal of this engineering and economic analysis is to influence some important future decisions regarding the systematic improvement and reconstruction of the existing buildings in order to permanently reduce energy expenditure and CO 2 emission. Rather than depriving the consumers in any way, energy saving benefits the environment, life quality, and competitiveness of the facility.

Soft drinks poly(ethylene terephthalate) (PET) bottles were depolymerized by glycolysis with different molar ratio of glycol, such as propylene glycol (PG), triethylene glycol (TEG) and poly(ethylene glycol) (PEG 400), in the presence of a zinc acetate catalyst. These glycolyzed products were characterized by hydroxyl value (HV) determinations. The obtained glycolyzed products were reacted with isophorone diisocyanate (IPDI), dimethylol propionic acid (DMPA), as potential ionic center for water dispersibility, and mixed with ethylene diamine (EDA) as extender chain to prepare polyurethane dispersions. The PET glycolyzed products and polyurethane formation were characterized using Fourier transform infrared spectroscopy (FTIR). The molecular masses distribution of oligoester polyol and polyurethane dispersions were determined by using gel permeation chromatography (GPC). The effect of different PET/glycol molar ratio, on the physico-mechanical properties, such as hardness, adhesion test and gloss of polyurethane films were investigated. Thermal properties were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). It was observed that initial degradation temperatures were at about 200 °C, with two-or three degradation steps. The influence of different molar ratio PET/glycol on DTG curves showed stages that were not noticeable in the appropriate weight loss curves. Polyurethane dispersions which lower molar ratio of PET/glycol in glycolyzed products showed lower thermal stability due to the presence of a greater amount of aromaticity in polyester backbone led to materials with higher film hardness. The values for the film adherence and gloss were confirmed their excellent properties for potential application for coatings in civil engineering, metal or polymer industry.

Properties of coatings based on alkyd resin can be improved via blending with other suitable resins. Recent studies assessed that many properties could be improved by blending with epoxy resins as well as with melamine resins. The aim of this work was to investigate the effect of epoxy resin content on the curing process in alkyd–melamine–epoxy three component blends. The coatings with two mixing ratios of alkyd/melamine (70:30 and 80:20) were formulated. They were made into baking enamels by blending with 3 and 5 wt% of epoxy resin on total resin solid. Curring kinetics was investigated by differential scanning calorimetry (DSC) and application of Ozawa isoconversional method. Fourier transform infrared spectroscopy (FTIR) was used to follow major curing reactions. The absorbance of –OH and –N–CH2R, showed significant reduction and confirmed that the epoxy resin reacts and inserts in enamel structure. It was found that resin system with alkyd/melamine ratio of 70:30 and 3 wt% of epoxy resin has the lowest apparent activation energy of 141.5 kJ mol−1 and needs the shortest time of 34.2 min to reach final apparent degree of cure. Isothermal DSC experiments have confirmed these findings. The samples with 30 wt% of melamine resin had higher hardness of baked enamels then samples with 20 wt%. They also showed an increase of hardness with the increase of epoxy resin content.

The main goal of this research was to evaluate the efficacy of 1-methylcyclopropene (1-MCP) on chlorophyll degradation, antioxidants activity and quality parameters of two bell peppers ( Capsicum annuum L.) cultivars; cv. Silica (an original red cultivar) and cv. H1530 ("ever-green" line) after 18 d storage at 7°C and 3 d at 20°C. Immediately after harvest, fruits were rinsed over brushes at 55°C for 15 s and were exposed to 1-MCP at concentrations of 300 nl/L or 450 nl/L for 24 h at 20°C prior to storage and shelf-life simulation. In both cultivars, 1-MCP at concentration of 450 nl/L was significantly more effective in reducing weight loss, maintaining firmness, reducing decay incidence, and inhibiting color development, than 300 nl/L and untreated control fruit. However, the color inhibition of green-harvested red cv. Silica was significantly more affected by 1-MCP at 450 nl/L, then 'ever-green' cv. H1530.1-MCP treatment reduced the rate of lipophilic antioxidant activity (LAA). The hydrophilic antioxidant activity (HAA) remained practically unchanged after storage period in comparison on the beginning of storage. In green pepper fruits, the HAA:LAA ratio was 1:5 and 1:8 depending on postharvest treatment (1-MCP, 300 or 450 nl/L) and cultivars differences. INTRODUCTION

A new post-harvest treatment for ‘Galia’-type melons has been developed for simultaneously clearing and disinfecting using hot water and brushes. Pre-storage heat treatment appears to be one of the most promising in post-harvest control decay. The efficiency of HWRB treatment was dependent on the temperature used and time of exposure. Fruits were placed on rotating brushes and rinsed with tap water followed by a hot water rinse (HWRB) at 50, 54, 58 and 60 ±1°C for 15 sec. The fruits were removed from the cartons and hand-sprayed until completely coated hand-sprayed with Zivdar wax (Safepack, Raanana, Decco, Israel) for melons, containing 2% (w/v) sodium bicarbonate (SBS) incorporated into wax represented the current commercial treatment. After drying, melons were repacked in the cartons and stored for 14 days at 2°C and 5°C and up to 5 days at 20°C (shelf life during retail and marketing). The optimal treatment to reduce decay while maintain fruit quality after prolonged storage and marketing simulation was 60 ±1°C for 15 sec. Treatment includes hot water drenching (60°C for 10-15 sec) applied while the fruit is rolling on soft brushes and followed by coating with a wax preparation containing 2% sodium bicarbonate. The efficacy of the new post-harvest practice (hot water washing, coating with wax preparation containing sodium bicarbonate) was confirmed in Galia melons. This practice improved the general appearance and reduced post-harvest decay while maintaining fruit quality.

The aim of this study was to analyze the growth response of HeLa cells over a prolonged period of time to a single exposure of physiological and supraphysiological concentrations of 4-hydroxynonenal (HNE), a peroxidation product of omega-6-polyunsaturated fatty acids. Furthermore, the growth modulating effect of serum factors, particularly albumin, on the growth pattern was examined. The effects of HNE on the growth rate and viability of the cells, as well as on the incorporation of labelled amino acids were monitored daily over a period of four days. Fetal calf serum not only had a growth stimulating effect but also modulated the action of HNE. In neither respect was albumin able to substitute for serum indicating that the influence of serum was not exerted via an albumin-HNE conjugate. HNE had a clear dose-dependent effect and a distinction could be made between a supraphysiological concentration (100 microM), which was primarily cytotoxic and a physiological range (below 10 microM) which showed growth modulatory effects. These effects consisted of a transient inhibition in the initial phase of the cell growth, which under optimal conditions (in presence of serum) was followed by a period of increased proliferation, compared to untreated control cultures, until confluence was attained. It is suggested that HNE is not only a toxic product of lipid peroxidation, but a physiological growth regulating factor as well.

There are numerous data on the immunostimulative and antitumorous activity of various Viscum album tissue extracts. Isorel (Novipharm, Austria) is one of these compounds. We found that in mice an increased number of plaque-forming cells to sheep red blood cells (SRBC) followed the injection of Isorel together with SRBC. Further, survival time of a foreign skin graft was shortened if Isorel was applied at the correct time. Finally, suppressed immune reactivity in tumorous mice recovered following Isorel injection. Isorel was further shown to be cytotoxic to tumor cells in vitro. Its application to tumor-bearing mice could prolong their life but without any therapeutic effect. However, a combination of local irradiation and Isorel was very effective: following 43 Gy of local irradiation to a transplanted methylcholanthrene-induced fibrosarcoma (volume about 240 mm3) growing in syngeneic CBA/HZgr mice, the tumor disappeared in about 25% of the animals; the addition of Isorel increased the incidence of cured animals to over 65%. The combined action of Isorel, influencing tumor viability on the one hand and the host's immune reactivity on the other, seems to be favorable for its antitumor action in vivo.

This paper presents the investigation of the air-pollution management possibility in Bor (Serbia) using statistical analyses of the correlation dependence of SO(2) pollution concentration and meteorological parameters. This kind of approach allows data to determine the shape of time trends; models serial correlation and dependence on covariance; and provides statistical analyses of data. Air quality control in the area of Bor is measured at four monitoring stations: City park; Institute of Mining and Metallurgy; Jugopetrol oil logistic centre and Brezonik suburb. There is also a meteorological station near the aforementioned institute that measures temperature; air humidity; atmosphere pressure; wind speed and direction. The results received from all monitoring stations are processed by the Institute of Mining and Metallurgy in Bor. The data from the reported documents were used for statistical analyses, for determining the correlation between SO(2) emission concentration and meteorological parameters. The source of SO(2) emissions is the local copper smelter, built within the town of Bor from 1961-1963. However, the disposition of the pollutant concentration is influenced by meteorological parameters (air humidity, atmosphere pressure, speed and wind direction). The successful application of these statistical analyses in this paper points to a possibility of its usage in air pollution studies.

Preparations of splenic peptides under the name of Polyerga are being tested in numerous experimental immunomodulating and antitumorous models and are also used during supportive treatment of tumorous patients. Further, the incidence of experimental lung metastases of melanoma cells in mice was significantly reduced if we used Polyerga preparations. The aim of our investigation was to determine whether Polyerga is active directly against tumor cells or whether its activity is manifested by modulating immune and other possible abilities of the organism. To clarify the problem glycopeptides containing Polyerga were incubated with melanoma B16F10 cells in vitro and the plating efficiency of these cells determined when cultivated in medium, or in medium with different doses of the same Polyerga preparation. The cells preincubated in medium only reacted to the addition of increasing doses of Polyerga, 150 pg or more, by raising colonies number. However, 24-h incubation of melanoma cells in the presence of 150 micrograms of Polyerga per ml significantly reduced the number of tumor cell colonies in comparison to the corresponding cell cultures previously not exposed to Polyerga. These in vitro studies were extended to in vivo application using C57B1/GoZgr mice injected i.v. with melanoma cells pretreated with Polyerga in vitro or previously not treated. A group of the treated mice was further injected i.p. with Polyerga. All the mice were killed at a particular time and the number of lung nodules determined. A significant difference to the control values was noticed in each group that used Polyerga, regardless of the exposure of melanoma cells to Polyerga in vitro, in vivo or to combined treatment. The efficiency of Polyerga application 7 days following i.v. injection of control melanoma cells (cultivated in medium only) when the nodules already exist, was further evaluated in a combined treatment using DTIC, a drug of choice in melanomas. The smallest incidence of experimental lung metastases was observed in the group exposed to the combination of DTIC and Polyerga. Polyerga preparation is thus active against melanoma cells, particularly in vivo and if combined with chemotherapy.

Argyrophil technique for presentation of interphase nucleolar organiser regions (AgNOR) is becoming an important method in tumour pathology which is used in diagnosis and prognosis. The number of interphase AgNOR is in the strict correlation with the degree of cell proliferation. We have used this technique in evaluation of degree of differentiation and proliferation of squamous changes of the epithelium of the bronchial mucosa. The statistically significant differences were found (p0.01) in the number of AgNOR by nucleus in cells of benignant squamous metaplasia (3.31) and epidermoid bronchial carcinoma (5.34). On the basis of numerical values of AgNOR epidermoid bronchial carcinomas could be divided into the group with low proliferative capability (AgNOR5.34) and in the group with high degree of proliferation (AgNOR5.34). Prognosis of patients with tumours with the high AgNOR value is poorer and they require additional systemic chemotherapy regardless of the clinical state of the disease at the moment of surgical intervention.

Although intensively studied, the mechanisms controlling tissue regeneration are still not completely understood. However, substantial data show that severe trauma, particularly burns, can impair the normal function of the immune system [14, 18]. It seems that wounding can cause both local and systemic disturbances in homeostasis, which could be further manifested even as shock or multiple organ failure. Furthermore, various pathological disorders influence protein synthesis in the liver, thus causing acute-phase response [7, 26]. However, the importance of acute-phase reactants in the regulation of homeostasis, such as tissue regeneration, immune system function, and perhaps even tumor growth control, is still uncertain. However, it seems that local growth regulating factors, as well as similar humoral factors play the most important role, at least during liver regeneration [6, 20, 28]. It is also known that the immune system itself is involved in the regulation of wound healing [2, 23].

Phenomenon of spontaneous regression of cancer indicates that recovery from malignant disease can happen without the application of any so far known therapeutic treatment. The most of the self-cured patients have undergone surgical operation which did not eliminate entire tumor or did not affect malignant tissue at all. Furthermore, regression or reversion of tumors (transformation of tumor cells into normal, nonmalignant cells) can be achieved in plants or amphibia after exposure of tumor cells to the influence of normal, regenerating tissue. Thus, it seems that during tissue regeneration certain local changes in tissue happen (synthesis of some regulatory growth factors) which induce dying of tumor cells or modify main features of malignant cells. Previously we have studied growth of murine malignant tumors in regenerating tissue of liver and skin. Obtained results indicated that under the influence of regenerating tissue anaplasia of fibrosarcoma decreases, as well as do pigmentation and the incidence of live cells in melanoma B16 tissue. Thus, it is obvious that mechanism of regenerating tissue growth control, which can also change characteristics of tumor cells, exists in mammalia, too. In order to analyse whether the same homeostatic mechanism is responsible for the phenomenon of spontaneous regression of human cancer, we have analysed the growth of melanoma B16 in back limb of nonoperated and sham or partially hepatectomized mice. Regeneration of skin and abdominal wall tissue in sham hepatectomized animals slowed down tumor growth, while liver regeneration completely inhibited tumor progression. Tumor growth inhibition was result of tumor tissue necrosis which developed around blood vessels. However, the structure and integrity of blood vessels themselves was normal.(ABSTRACT TRUNCATED AT 250 WORDS)

An extraction and spectrophotometric method for determination of trace amounts of uranium in phosphate fertilizers is described. It is based on the extraction of uranium with trioctylphosphine oxide in benzene and the spectrophotometric determination of uranium with Arsenazo III in buffer-alcoholic medium. The maximum absorbance occurs at 655 nm with a molar absorptivity of 1.2·104 l·mol−1·cm−1. Beer's law is obeyed over the range 0.6–15.0 μg·ml−1 of uranium(VI). The proposed method has been applied successfully to the analysis of phosphate fertilizers with phosphate concentrations of 45% P2O5.

Die in dieser Mitteilung erhaltenen Resultate lassen sich wie folgt zusammenfassen: 1. Hat man verschiedene Mengen Diphtherietoxin von ein und derselben Serie, so erhalt man, falls sich in betreffenden Vorratsflaschen ein Luftraum oberhalb der freien Toxinoberflache befindet, das die Reaktionsgeschwindigkeit in der Richtung der Anatoxinbildung, unter Einwirkung von Formaldehyd, bei kleineren Toxinmengen groser ist als umgekehrt. 2. Hat man gleiche Mengen von Diphtherietoxin, so findet man, das die Detoxikationsgeschwindigkeit unter sub 1. angefuhrten Bedingungen der freien Toxinoberflache symbat ist.

About each tenth woman having been confined in Valjevo's hospital was controlled at the Prenatal Guidance Unit of the Hospital's Maternity Ward. Out of the women controlled at the hospital, 2.5% had pre-term deliveries, while this percentage in other women having been controlled at the hospital's guidance unit.