The influence of human resource management on improvement of business ethics

In this paper the importance of practice of human resource management as of a significant driver of business ethics in companies has been considered. The basic premise of the paper is the fact that the company’s main source of unethical behaviour is situated in its people’s activities which further implies that many measures aimed to apply and improve business ethics belong to the domain of human resource management. Based on research results on a sample of 36 enterprises, the paper attempts to answer important questions as: what are the problems regarding business ethics facing human resource experts and to what extent the existing human resource management practices influence the application and improvement of business ethics in Serbian enterprises.Business ethics, human resource management, ethical workplace, employees., Labor and Human Capital, M12, M50,

Connecting the Centre of Belgrade with the Danube and Sava Riverfronts to Increase Attractiveness

Although Belgrade is set on the confluence of two rivers, its riverfronts have never been an integral part of the city, due to the barriers between its historical urban core and the waterfronts. Over the last decade, these areas have come into focus because of their potential for becoming one of the most attractive and important ambient urban environments. In this research, a method for the inclusion of the Sava riverfronts into the urban life of its users was established through an analysis of the quality and intensity of open public spaces and the possibility for improving the pedestrian networks. The area known as Kosančićev Venac has been chosen as a case study, being an important connection between these two sites with its cultural values, tradition and identity. The methods used were observation and content analysis of existing literature, strategies and planning documents. In accordance with a participatory approach, direct surveying of selected stakeholders was developed through interviews and questionnaires and a method of mapping users on social maps. Two main groups of users were included in this research: citizens and tourists. Furthermore, the results were presented in the form of a SWOT analysis showing the main obstacles and barriers, but also the strengths and of open public spaces and a pedestrian network. In conclusion, this paper could serve as a knowledge base for developing future strategies containing specific guidelines for revival and inclusion of riverfront areas, in order for city waterfronts to live up to their full potential

Use of Bed Materials in Dual Fluidized Bed (DFB) Systems

Dual Fluidized Bed (DFB) gasification is one alternative for the production of biofuels. In a DFB gasification process, the bed material plays a crucial role. Primary role of the bed material is to provide the heat needed for the gasification reaction. If the bed material, used in the system, is catalytically active it can improve the quality of the produced gas. In addition, inorganics originate from the biomass are retained in the system in the form of ash, which interacts with the bed material, thus representing catalytic potential. As a consequence of being circulated between oxidative and reductive environments, the bed material releases some inorganics into the gas phase, thereby influencing the final composition of the produced gas. The goal of the present work is to increase our understanding as to how changes in the bed material related to reactions with ash components can be utilized to improve the performance of the system. In this way, it should be possible to optimize the gasification step, thereby decreasing the cost of biofuel production. Moreover, by choosing naturally occurring bed materials not only the cost of the process is decreased, but also negative impact on the environment which comes with the disposal of the material. This work deals with the application of catalytic bed materials in dual fluidized bed systems, both as a primary measure in the gasification process itself and as a secondary measure for the reforming of the raw gas. Applied directly in the gasification step, the bed material interacts with the inorganics derived from the fuel. As a result of this interaction, the bed material changes its physical and chemical properties, which has impacts for the gasification process. In the present study, four naturally occurring materials were evaluated. In the Chalmers 2–4-MWth gasifier, the effects on the gasification process of interactions between the ash and the bed material were studied for quartz-sand and olivine. The effects on the process were evaluated with respect to: 1) the composition of the produced gas; 2) tar content; and 3) the physicochemical properties of the bed material. The studies yield information about the transport of inorganics between the reactors and their influences on the gas composition. Whereas the release of alkali during gasification implies a potential for enhancement of the gas quality, the presence of these same species represents a risk for agglomeration during combustion. In the Chalmers 12–MWth boiler, ilmenite was tested as the bed material and as an alkali getter material. The adsorption of potassium to the ilmenite is shown to be non-reversible, and ilmenite shows great promise as a material for decreasing bed agglomeration in fluidized bed boilers. As a secondary measure, downstream of the gasifier, manganese ore was evaluated for its tar-reforming capability in a dual fluidized bed reactor system, in a process known as chemical looping reforming. This material has the ability to reduce tar levels by as much as 72%, while having high activity towards hydrogen production

Use of Bed Materials in Dual Fluidized Bed (DFB) Systems

Dual Fluidized Bed (DFB) gasification is one alternative for the production of biofuels. In a DFB gasification process, the bed material plays a crucial role. Primary role of the bed material is to provide the heat needed for the gasification reaction. If the bed material, used in the system, is catalytically active it can improve the quality of the produced gas. In addition, inorganics originate from the biomass are retained in the system in the form of ash, which interacts with the bed material, thus representing catalytic potential. As a consequence of being circulated between oxidative and reductive environments, the bed material releases some inorganics into the gas phase, thereby influencing the final composition of the produced gas. The goal of the present work is to increase our understanding as to how changes in the bed material related to reactions with ash components can be utilized to improve the performance of the system. In this way, it should be possible to optimize the gasification step, thereby decreasing the cost of biofuel production. Moreover, by choosing naturally occurring bed materials not only the cost of the process is decreased, but also negative impact on the environment which comes with the disposal of the material. This work deals with the application of catalytic bed materials in dual fluidized bed systems, both as a primary measure in the gasification process itself and as a secondary measure for the reforming of the raw gas. Applied directly in the gasification step, the bed material interacts with the inorganics derived from the fuel. As a result of this interaction, the bed material changes its physical and chemical properties, which has impacts for the gasification process. In the present study, four naturally occurring materials were evaluated. In the Chalmers 2–4-MWth gasifier, the effects on the gasification process of interactions between the ash and the bed material were studied for quartz-sand and olivine. The effects on the process were evaluated with respect to: 1) the composition of the produced gas; 2) tar content; and 3) the physicochemical properties of the bed material. The studies yield information about the transport of inorganics between the reactors and their influences on the gas composition. Whereas the release of alkali during gasification implies a potential for enhancement of the gas quality, the presence of these same species represents a risk for agglomeration during combustion. In the Chalmers 12–MWth boiler, ilmenite was tested as the bed material and as an alkali getter material. The adsorption of potassium to the ilmenite is shown to be non-reversible, and ilmenite shows great promise as a material for decreasing bed agglomeration in fluidized bed boilers. As a secondary measure, downstream of the gasifier, manganese ore was evaluated for its tar-reforming capability in a dual fluidized bed reactor system, in a process known as chemical looping reforming. This material has the ability to reduce tar levels by as much as 72%, while having high activity towards hydrogen production

GMS proteins shield endocellular membranes from accumulation of effector Immunity-Related GTPases

GMS proteins shield endocellular membranes from accumulation of effector Immunity-Related GTPases Jelena Maric-Biresev Immunity-related GTPases (IRGs) play an important role in host immune response to a variety of intracellular pathogens by accumulation at the membranes of the pathogens and their disruption. However, it was never understood how exactly IRG proteins distinguish the membranes of the pathogen from the host membranes. Previously, it has been reported that regulatory IRG proteins, named GMS proteins, keep the effector IRG proteins, named GKS proteins, in the inactive GDP-bound state. In this study, it has been shown that GMS proteins also play an important role in protection of the endocellular compartments from GKS protein off-target activation. In the absence of the GMS protein Irgm1, which is localized at the lysosomes, GKS proteins Irga6, Irgb6, Irgb10 and Irgd accumulate and activate at these organelles. In the absence of Irgm3, a GMS protein which is localized at the endoplasmic reticulum (ER), GKS protein Irga6 accumulates at the ER. However, in the cells that lack Irgm1 and Irgm3, GKS proteins accumulate only to lipid droplets, but not to lysosomes or ER, indicating that GKS structures do not accumulate at every GMS-free membrane. In the second part of the study, the consequences Irgm1 accumulation to the lysosomes are investigated. Irgm1 KO mice undergo leukopenia and succumb after a variety of infections and inflammatory states. The results of this study suggest that the failure of Irgm1 KO mice is rather an indirect consequence of the off-target action of the GKS proteins, than the direct consequence of the Irgm1 response to a variety of pathogens. The GKS proteins, that accumulate at the lysosomes in Irgm1 KO cells, affect the acidity of these organelles and therefore lysosomal ability to process autophagosomes. In IFNγ-induced Irgm1 KO mouse embryonic fibroblasts (MEFs) the mature autophagosome marker LC3-II level is enhanced, the number of autophagosomes is increased and the co-localization between autophagosomes and lysosomes is higher than in the non-induced cells. Therefore, in this study, it is proposed that the autophagic flux of IFNγ-induced Irgm1 KO MEFs is impaired. The lymphocytes of the Irgm1 KO mice, that are stimulated to proliferate as a response to infection, could be the cells that are most affected by autophagic flux arrest and lysosomal acidification impairment. Thus, this effect could be the cause of described defects in lymphocyte proliferation and lymphocyte necrosis, which cause the death of the Irgm1 KO mous

Mapping the effects of potassium on fuel conversion in industrial-scale fluidized bed gasifiers and combustors

Potassium (K) is a notorious villain among the ash components found in the biomass, being the cause of bed agglomeration and contributing to fouling and corrosion. At the same time, K is known to have catalytic properties towards fuel conversion in combustion and gasification environments. Olivine (MgFe silicate) used as gasifier bed material has a higher propensity to form catalytically active K species than traditional silica sand beds, which tend to react with K to form stable and inactive silicates. In a dual fluidized bed (DFB) gasifier, many of those catalytic effects are expected to be relevant, given that the bed material becomes naturally enriched with ash elements from the fuel. However, a comprehensive overview of how enrichment of the bed with alkali affects fuel conversion in both parts of the DFB system is lacking. In this work, the effects of ash-enriched olivine on fuel conversion in the gasification and combustion parts of the process are mapped. The work is based on a dedicated experimental campaign in a Chalmers DFB gasifier, wherein enrichment of the bed material with K is promoted by the addition of a reaction partner, i.e., sulfur, which ensures K retention in the bed in forms other than inactive silicates. The choice of sulfur is based on its affinity for K under combustion conditions. The addition of sulfur proved to be an efficient strategy for capturing catalytic K in olivine particles. In the gasification part, K-loaded olivine enhanced the char gasification rate, decreased the tar concentration, and promoted the WGS equilibrium. In the combustion part, K prevented full oxidation of CO, which could be mitigated by the addition of sulfur to the cyclone outlet

Correlation between Fitness and Fatness in 6-14-year Old Serbian School Children

Lack of physical activity and/or physical fitness are some reasons epidemiologists suggest for increase in childhood obesity in the last 20 years, with clear correlation between body composition and physical activity and/or physical fitness yet to be determined. The objectives of the study were to (a) investigate the prevalence of overweight and obesity among Serbian school children and (b) determine the relationship between indicators of physical activity and body fatness in Serbian school children aged 6-14 years. The study subjects included a representative sample of Serbian elementary school children (n=1, 121—754 boys and 367 girls—aged 6.2-14.1 years), all of whom were recruited in the OLIMP (Obesity and Physical Activity among Serbian School Children) study. Anthropometric and physical fitness values, including body mass index (BMI), waist-circumference, body-fat, and aerobic capacity, were measured in all the children. Significant differences were found between male and female children regarding the prevalence of obesity (6.8% vs 8.2%, p<0.05, boys and girls respectively). Boys had significantly lower body mass, BMI, waist-circumference, sum of six skinfolds, and body-fat compared to their female counterparts (p<0.05). The highest level of weight, BMI, body-fat, and waist-circumference observed in a 14-year old girl (96.3 kg, 40.5 kg/m2, 54.5%, 91.4 cm respectively) implies the existence of extreme obesity in Serbian school children. The negative relationship between body-fat and maximal oxygen (VO2max) uptake was moderately high (r=-0.76; p<0.05). The study has shown a high prevalence of adiposity among Serbian school children, with a strong negative relationship between aerobic fitness and body fatness. Data of the study emphasize the necessity to identify children with weight problems and to develop early interventions to improve physical activity in children and prevent the increase of childhood obesity

Feedstock recycling of cable plastic residue via steam cracking on an industrial-scale fluidized bed

The use of plastic materials in a circular way requires a technology that can treat any plastic waste and produce the same quality of product as the original. Cable plastic residue from metal recycling of electric wires is composed of cross-linked polyethene (XLPE) and PVC, which is a mixture that cannot be mechanically recycled today. Through thermochemical processes, polymer chains are broken into syngas and monomers, which can be further used in the chemical industry. However, feedstock recycling of such a mixture (XLPE, PVC) has been scarcely studied on an industrial scale. Here, the steam cracking of cable plastic was studied in an industrial fluidised bed, aiming to convert cable plastics into valuable products. Two process temperatures were tested: 730 \ub0C and 800 \ub0C. The results show that the products consist of 27–31 wt% ethylene and propylene, 5–16% wt.% other linear hydrocarbons, and more than 10 wt% benzene. Therefore, 40%–60% of the products are high-value chemicals that could be recovered via steam cracking of cable plastic

Interactions between Automotive Shredder Residue and Olivine Bed Material during Indirect Fluidized Bed Gasification

Thermal conversion of automotive shredder residue (ASR) using indirect fluidized bed gasification was conducted in the Chalmers semi-industrial 2-4-MWth gasifier. The bed material consisted of olivine that was activated through the deposition of biomass ash prior to a 13-day exposure to ASR. The interactions between the bed material and the ASR ash were investigated using XRD, SEM-EDS, and thermodynamic modeling. The deposition of iron (Fe) onto the olivine particles was noted, and this is likely to increase the oxygen-carrying ability of the particles. Furthermore, at the end of the campaign, about one-third of the particles in the bed were found to originate from the ASR ash. These particles were rich in Fe and Si, as well as elements found exclusively in the ASR ash, such as Zn, Ti, and Cu. Some of these particles exhibited a hollow morphology, suggesting a melt state during their formation in the gasifier. In addition, a low level of agglomeration of the ash and olivine particles was detected. Thermodynamic modeling with the FactSage software indicated the formation of slag. This study presents a detailed investigation of the interactions that occur between the bed material and an ash-rich fuel such as ASR. The findings may have applications in demonstrating the induction of oxygen-carrying ability in bed materials or for metal recycling through the separation of ash particles from the bed material

Fate of lead, copper, zinc and antimony during chemical looping gasification of automotive shredder residue

Gasification experiments in this study were performed in a 2–4 MW indirect gasifier coupled to a semi-commercial CFB combustor at Chalmers University of Technology. Experiments were carried out during 13 days with automotive shredder residue (ASR), giving a unique opportunity to investigate the bed material under realistic conditions and with long residence times. The metal rich ash was accumulated in the bed, gaining some oxygen carrying capabilities, creating a chemical looping gasification (CLG) process. This study aims to expand the knowledge about the chemistry of zinc, copper, lead and antimony during CLG of ASR. Several experimental methods have been utilized, such as XRD, SEM-EDX and XPS along with detailed thermodynamic calculations to study chemical transformations that can occur in the system. Thermodynamic calculations showed that the reduction potential affect the phase distribution of these elements, where highly reduction conditions result in heavy metals dissolving in the slag phase. Copper and zinc ferrites, lead silicates and antimony oxides were identified at the particle surfaces in the bottom ash. The formation of an iron rich ash layer plays an important role, especially for copper and zinc speciation. The main pathways in the complex CLG system have been discussed in detail