Chester Barnard: Organisational-Management Code for the 21st Century

Barnard thought that it was possible to improve effectiveness and efficiency through formal organization. He was trying to understand how to obtain organizational survival "maintaining equilibrium of complex character in permanent turbulent environment of physical, biological and social materials and elements and forces" within the organization, exploring in parallel the outer powers to which the organization must adapt on all levels and analysing the functions which in that context are performed by executive directors in the organization as a whole system. This paper explores the influences of Chester Barnard on Blake and Mouton's leadership-management network, Hersey-Blanchard's situational leadership and Maslow's motivational theory, as well as on organisational purpose, communication and team work. This paper examines the relevance of the principles and theories developed by Barnard from the point of today's managers and leaders. According to Barnard, this can be achieved through linking Barnard's central ideas with new concepts of management and leadership. Our opinion is that even today Barnard represents a very important part of the chain of examination and exploration of management and leadership thought. (C) 2015 The Authors. Published by Elsevier Ltd

Combined GSTM1 and GSTT1 null genotypes are strong risk factors for atherogenesis in a Serbian population

Oxidative stress (OS) plays an important role in atherogenesis and since glutathione S-transferases (GSTs) provide protection against OS, we have tested the hypothesis that deletion polymorphisms in two GSTs (GSTM1 and GSTT1) may affect the risk of developing atherosclerosis. A total of 382 individuals (200 patients with atherosclerosis and 182 healthy controls) were included in this association study. Genomic DNA was isolated from peripheral blood cells or from buccal epithelial cells and genotyping was performed using multiplex-PCR or real-time PCR methods. GSTM1 null genotype was significantly more frequent in atherosclerotic patients than in controls (52.0% vs 34.1%) and individuals with the GSTM1 null genotype had an approximately 2-fold increase in atherosclerosis risk (OR: 2.1, 95%CI=1.39-3.17, P=0.0004). GSTT1 null genotype alone did not show a statistically significant effect on atherosclerosis risk modulation, but the association approached significance (OR: 1.57, 95%CI=0.94-2.64, P=0.08). The combined analysis showed that the presence of both genes had a protective effect against atherosclerosis (OR=0.55, 95%CI=0.37-0.83, P=0.005) while double null genotypes led to a robust atherosclerosis risk increase (OR: 8.14, 95%CI=2.41-27.51, P lt 0.0001). This study demonstrated that the GSTM1 null and combined GSTM1/GSTT1 null genotypes are susceptibility factors for development of atherosclerosis in a Serbian population

Carcass characteristics and meat quality of broilers fed on earthworm (Lumbricus rubellus) meal

The aim of the research was to evaluate the carcass characteristics and meat quality from chickens fed on diets in which fish meal was substituted with raw earthworms (Lumbricus rubellus) or earthworm meal. In the trial which lasted 42-days, 100 one-day-old Hybro broilers were divided into the control and three experimental groups. The control group was fed on standard broiler feed, the first (E-I) and the second experimental groups (E-II) were fed a diet in which 50% or 100% of fish meal was substituted with earthworm meal, respectively, whilst the third group (E-III) consumed feed without fish meal, but was given raw chopped earthworms ad libitum from day 1 to day 42. The replacement of fish meal with fresh earthworms resulted in significantly lower carcass weights in the E-III group in comparison with the control group (p lt 0.05). The differences in drumstick, thigh and breast meat share relative to the carcass mass were not significant (p>0.05). The lowest fat content in thigh and breast meat was in the group in which fish meal was replaced with earthworm meal. The lightness (L*) of thigh and breast meat was highest in the broilers fed fresh earthworms ad libitum. No significant differences in pH value were detected between the experimental groups (p>0.05). The most consumer acceptable were drumstick samples from E-II group and the least acceptable samples from the control group. Earthworm meal may be considered an adequate substitute for fish meal in broiler chickens' diet since it does not impair the production performance, carcass yield and meat quality

Variants in vdr and nramp1 genes as susceptibility factors for tuberculosis in the population of Serbia

Tuberculosis (TB) is granulomatous diseases caused by Mycobacterium tuberculosis (MTB). TB is a highly infectious disease that primarily affects the lungs. One-third of human population is infected with MTB, therefore it is of utmost significance to determine the factors that influence the individual susceptibility to the disease. Host genetic factors have been recognized as essential for susceptibility to TB, since only 5% to 10% of infected individuals develop the disease. A number of candidate genes has been intensively studied, the most of which were connected with the function of macrophages, thus participating in immune response. Here we examined the gene variants of VDR (FokI) and NRAMP1 (INT4, D543N, 3'UTR) genes in aim to make the correlation between these genetic factors and risk of TB in Serbian patients. This study included 110 TB patients and 67 healthy controls. Pulmonary TB was diagnosed by clinical symptoms, radiological evidence of TB and bacteriological criteria (Culture-positive/smear-positive). Genotyping was performed using PCR-RFLP method. Our findings revealed significant prevalence of ff genotype and variant allele f of the FokI VDR gene variant in patients compared to control group. Based on the our results the carriers of ff genotype are five times more at risk to tuberculosis than carriers of FF and Ff genotype in our population. The results of analyzed SNPs in NRAMP1 gene showed no statistically significant difference in distribution of the gene variants between patient and control groups. Therefore, we could conclude that the genotype ff of the VDR gene is factor that strongly contribute to susceptibility to TB in Serbian population

Genes and metabolic pathway of sarcoidosis: identification of key players and risk modifiers

Introduction: Sarcoidosis is a rare multisystem granulomatous disease with unknown etiology. The interplay of vitamin D deficiency and genetic polymorphisms in genes coding for the proteins relevant for metabolism of vitamin D is an important, but unexplored area. The aim of this study was to investigate the association between single nucleotide polymorphisms (SNPs) in CYP2R1 (rs10741657), CYP27B1 (rs10877012), DBP (rs7041; rs4588), and VDR (rs2228570) genes and sarcoidosis, as well as the association between these SNPs and 25(OH)D levels in sarcoidosis patients. Material and methods: For that purpose we genotyped 86 sarcoidosis patients and 50 healthy controls using the PCR-RFLP method. Results: Subjects carrying the CC genotype of CYP27B1 rs10877012 have 10 times lower odds of suffering from sarcoidosis. Moreover, DBP rs4588 AA genotype was shown to be a susceptibility factor, where carriers of this genotype had eight times higher odds for developing sarcoidosis. In addition, the A allele of the DBP gene (rs4588) was associated with lower levels of 25(OH)D in sarcoidosis patients. Conclusions: These results suggest that patients with vitamin D deficiency should be regularly tested for genetic modifiers that are related to sarcoidosis in order to prevent development of serious forms of sarcoidosis

The galena flotation in function of grindability

This paper presents the results of industrial research of influence of grinding fineness on the results of galena mineral flotation from the ore of the mine "Rudnik." Based on these results, it has been concluded that with one-stage grinding and one-stage classification of complex Pb-Zn-Cu ore galena is the most easily grinded mineral within the ore

The mutual effect of extracellular Ca2+, abscisic acid, and pH on the rate of stomatal closure

An analysis of the rate of stomatal closure in epidermal strips of Commelina communis L. induced by different calcium concentrations (10 nM to 1 mM) demonstrated a biphasic dependency, the initial process of closure being more calcium dependent. This dependency was more evident at pH 7 than pH 5 of the bathing medium. Addition of low concentrations of abscisic acid (10 nM) induced a broadening of the Ca-2 dependency, while 10 mu M abscisic acid increased the rate of stomatal closure in the whole Ca2+ range and to a large extent abolished the calcium-induced effects. Such results indicate an interaction of external protons, Ca2+, and abscisic acid, and possible competition for the membrane associated binding sites of the mechanism(s) responsible for the regulation of stomatal closure

Outwardly Rectifying Anionic Channel from the Plasma Membrane of the Fungus Phycomyces blakesleeanus

In the present report, by using a patch clamp technique, we provide, to our knowledge, the first detailed description of an anionic channel from filamentous fungi. The characterized channel, an outwardly rectifying anionic channel (ORAC), is the most prominent feature of the cell membrane of the fungus Phycomyces blakesleeanus in the absence of energizing substrates. The unitary conductance of the channel is 11.3 +/- 0.4 pS. It is characterized by a strong voltage dependence of the open-channel probability (z delta; the gating charge is 2.1 +/- 0.1), and the channel is activated by depolarization. The values of the time constants for voltage-induced activation and deactivation of 28 +/- 3 ms for tau(a) and 39 +/- 9 ms for tau(d) show that the ORAC is characterized by fast activation/deactivation kinetics. The ORAC shows strong selectivity for anions over cations and weak selectivity among anions, with a selectivity sequence of I- >= NO(3)(-) > Br(-) > Cl(-) > SO(4)(2-) = 4.8 > 4.4 > 2.2 > 1 > 0.55, which corresponds to Eisenman series 1. The channel is characterized by two open and two closed states, with dominant long open (tau(o2) = 35.0 +/- 3.9 ms) and long closed (tau(c2) = 166 +/- 28 ms) states occupying 63% +/- 8% and 79% +/- 3% of total open and closed times, respectively. The ORAC is insensitive to anthracene-9-carboxylic acid (< 200 mu M), but 2 mM malate reversibly inhibits 59% +/- 12% of the channel activity. Based on the electrophysiological properties of the channel, we propose that the ORAC plays a role in anion accumulation and in membrane potential regulation through local membrane depolarization.Ministry of Science of the Republic of Serbia [OI143016

Analysis of the treatment of plastic from electrical and electronic waste in the republic of Serbia and the testing of the recycling potential of non-metallic fractions of printed circuit boards

This paper presents the analysis of the quantity of plastic and waste printed circuit boards obtained after the mechanical treatment of electrical and electronic waste (E-waste) in the Republic of Serbia, as well as the recycling of non-metallic fractions of waste printed circuit boards. The aim is to analyze the obtained recycled material and recommendation for possible application of recyclables. The data on the quantities and treatment of plastics and printed circuit boards obtained after the mechanical treatment of WEEE, were gained through questionnaires sent to the operators who treat this type of waste. The results of the questionnaire analysis showed that in 2014 the dismantling of E-waste isolated 1,870.95 t of plastic and 499.85 t of printed circuit boards. In the Republic of Serbia, E-waste recycling is performed exclusively by using mechanical methods. Mechanical methods consist of primary crushing and separation of the materials which have a utility value as secondary raw materials, from the components and materials that have hazardous properties. Respect to that, the recycling of printed circuit boards using some of the metallurgical processes with the aim of extracting copper, precious metals and non-metallic fraction is completely absent, and the circuit boards are exported as a whole. Given the number of printed circuit boards obtained by E-waste dismantling, and the fact that from an economic point of view, hydrometallurgical methods are very suitable technological solutions in the case of a smaller capacity, there is a possibility for establishing the facilities in the Republic of Serbia for the hydrometallurgical treatment that could be used for metals extraction, and non-metallic fractions, which also have their own value. Printed circuit boards granulate obtained after the mechanical pretreatment and the selective removal of metals by hydrometallurgical processes was used for the testing of the recycling potential. Granulometric analysis as well analysis of chemical composition of obtained fractions was performed. Subsequently, the manual classification of different types of polymeric material contained in the granulate was made, and both the apparent specific gravity and the chemical composition of the classified types of polymeric materials were determined. Chemical composition of granulate was determined by X-Ray Fluorescence (XRF) using Thermo Scientific Niton XL 3t, while the identification of residual polymers was determined by the FTIR (Fourier Transform Infrared Spectroscopy) method on the Bomen MB 100 device in range 4000 to 400 cm(-1). Based on the results of this study, it can be concluded that after the hydrometallurgical treatment of printed circuit boards, and the separation of metals that have the highest value, the residual non-metallic fraction have the utility value and can be used for various purposes, such as developing new polymer materials for technical purposes that have been investigated by many researchers and mentioned in this article

Outwardly Rectifying Anionic Channel from the Plasma Membrane of the Fungus Phycomyces blakesleeanus

In the present report, by using a patch clamp technique, we provide, to our knowledge, the first detailed description of an anionic channel from filamentous fungi. The characterized channel, an outwardly rectifying anionic channel (ORAC), is the most prominent feature of the cell membrane of the fungus Phycomyces blakesleeanus in the absence of energizing substrates. The unitary conductance of the channel is 11.3 +/- 0.4 pS. It is characterized by a strong voltage dependence of the open-channel probability (z delta; the gating charge is 2.1 +/- 0.1), and the channel is activated by depolarization. The values of the time constants for voltage-induced activation and deactivation of 28 +/- 3 ms for tau(a) and 39 +/- 9 ms for tau(d) show that the ORAC is characterized by fast activation/deactivation kinetics. The ORAC shows strong selectivity for anions over cations and weak selectivity among anions, with a selectivity sequence of I- >= NO(3)(-) > Br(-) > Cl(-) > SO(4)(2-) = 4.8 > 4.4 > 2.2 > 1 > 0.55, which corresponds to Eisenman series 1. The channel is characterized by two open and two closed states, with dominant long open (tau(o2) = 35.0 +/- 3.9 ms) and long closed (tau(c2) = 166 +/- 28 ms) states occupying 63% +/- 8% and 79% +/- 3% of total open and closed times, respectively. The ORAC is insensitive to anthracene-9-carboxylic acid (< 200 mu M), but 2 mM malate reversibly inhibits 59% +/- 12% of the channel activity. Based on the electrophysiological properties of the channel, we propose that the ORAC plays a role in anion accumulation and in membrane potential regulation through local membrane depolarization.Ministry of Science of the Republic of Serbia [OI143016