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Introduction: Low-frequency electromagnetic field (50 Hz) (EMF) can modify crucial neuronal processes. Existing data indicate that exposure to EMF may represent a mild stressor and contribute to disturbances of the hypothalamic-pituitary-adrenal (HPA) axis. The important regulatory pathways controlling HPA axis activity include two types of corticosteroid receptors: mineralocorticoid receptors (MRs) and glucocorticoid receptors. They are particularly abundant in the hippocampus, a key locus of HPA axis feedback control. The research aimed at determining whether (1) EMF exhibits hormesis, it means bidirectional action depending on EMF intensity (1 or 7 mT) and (2) repeated EMF exposure changes stress response to subsequent stress factors. Methods: The exposure (7 days, 1 h/day) of adult rats to EMF (1 mT and 7 mT) was repeated 3 times. HPA axis hormones and their receptors were analysed after each following exposure. Moreover, the impact of EMF exposure on hormonal and behavioural responses to subsequent stress factor – open-field test was evaluated. Results: Our data suggest that exposure to EMF can establish a new “set-point” for HPA axis activity. The direction and dynamics of this process depend on the intensity of EMF and the number of exposures. EMF of 1 mT induced an adaptive stress response, but 7 mT EMF caused sensitization. Consequently, EMF changed the vulnerability of the organism to a subsequent stress factor. We have also shown the increase in MR mRNA abundance in the hippocampus of 1 mT EMF-exposed rats, which can represent the possible neuroprotective response and suggest therapeutic properties of EMFs.

Studies reported evidence for opposite effects of extremely low-frequency electromagnetic field (EMF): harmful, including the oxidative stress induction, and beneficial, such as the activation of antioxidant defense. People’s exposure to EMF is often repeated or prolonged, and it is important to consider the cumulative effect of such kind of exposure on the organism. If changes evoked by repeated exposure to EMF are permanent, responsiveness to other stress factors can be modified. The aims of our study were (1) to evaluate changes in the levels of oxidative stress and antioxidant defense markers in the prefrontal cortex of adult rats after repeated exposure to 1 and 7 mT EMF and (2) to assess whether repeated EMF exposure can modify oxidative/antioxidative status in response to other stress factors. Rats were exposed to EMF 1 h/day for 7 days, one, twice, or three times. After each exposure, 8-isoprostanes, protein carbonyl groups, and the total antioxidant capacity were assessed. Part of the animals, after EMF treatment, was exposed to another stress factor—open field. Results showed that repeated exposure changed the oxidative/antioxidative status depending on the intensity of the EMF and the number of exposures. 1 mT EMF created weak changes in the oxidative status in the brain; however, 7 mT EMF moved the balance to a clearly higher level. The changes in the oxidative status after 1 mT EMF were enough to reduce, and after 7 mT EMF to intensify oxidative processes in response to the next stress. We concluded that the organism might adapt to “weak” EMF, while “strong” EMF exceeds the adaptive capacity of the organism and sensitizes it to subsequent stress, and thus may modulate vulnerability to diseases. Our results also provide new insights into the possible therapeutic properties of the magnetic field, as 1 mT EMF appears to have a potentially protective impact on the brain.

This work presents the current state of knowledge about the possible contributory influence of the electromagnetic field on the occurrence of neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease, amyotrophic lateral sclerosis, and multiple sclerosis. Up-to-date literature indicates both favourable and adverse effects of electromagnetic exposure on human health, making it difficult to come to valid and unambiguous conclusions. The epidemiological data analysis from the World Health Organization statistics shows a substantial rise in neurological mortality compared with rises in total populations in developed countries over a mere 15-year period. The largest of the analysed countries produced odds ratios of >100%. The contribution of electromagnetic exposure to the incidence of neurodegenerative diseases is still undoubtedly open to discussion, and it requires further in-depth research to assess the action mechanism of electromagnetic fields in neurodegenerative diseases. The limitations of research published hitherto and the problem of drawing unequivocal conclusions are also in focus.

Members of TRP receptor family are involved in response to acidification. Here, we determined the effect of capsaicin, one of the TRP receptor activators, on hemolymph acid-base status in the American cockroach.

The aim of this work is to present the current knowledge about the possible participation of electromagnetic fields in the occurrence and also in treatment of neurodegenerative diseases. The literature data indicate both the negative and positive effects of electromagnetic fields and not allow to draw unambiguous conclusions. Undoubtedly, the topic is still open and needs further intensive research to finally assess the mechanism of action of the electromagnetic field on neurodegenerative diseases.

Epidemiological data suggest that there is a link between exposure to extremely low-frequency magnetic fields (ELF-MFs), immune response, and the occurrence of neurodegenerative diseases. The exact nature of this phenomenon remains speculative and requires detailed laboratory investigation. In the present study, we evaluate changes in plasma concentration of pro-inflammatory and regulatory cytokines as well as alternations of the hematological parameters in rats exposed to an ELF-MF.Male Wistar rats were repeatedly exposed for either 1 h/day for 7 days, or continuously for 24 h, to a sinusoidal ELF-MF (50 Hz, 7 mT). Control groups were sham exposed for either 1 h/day for 7 days, or continuously for 24 h, respectively. The levels of cytokines: interleukin (IL)-1β, IL-2, IL-6, and IL-10 in plasma obtained from blood samples were determined using enzyme-linked immunosorbent assay (ELISA). The changes in blood parameters were determined using an automatic hematology analyzer in whole blood samples immediately after collection.We found that a single continuous (lasting 24 h) exposure provoked a significant increase of the plasma IL-1β, IL-6, and IL-2 levels, and caused an elevation in blood parameters, such as white blood cells, lymphocytes, hemoglobin, and hematocrit levels. In contrast, however, repetitive exposure of rats to an ELF-MF for 1 h/day for 7 days did not lead to any changes in plasma levels of cytokines and hematological counts.Based on these data we conclude that exposure duration (dose-response) plays a significant role in the immune response, specifically at the cellular level. While single 24 h-lasting exposure provoked changes that indicate an immune alarm stimulation, under the conditions which are typical for therapeutic use of ELF-MFs (repeated short daily exposure) the immune potentially harmful response has not been observed.

Exposure to electromagnetic field (EMF) induces physiological changes in organism that are observed at different levels—from biochemical processes to behavior. In this study, we evaluated the effect of EMF exposure (50 Hz, 7 mT) on cockroach’s response to noxious heat, measured as the latency to escape from high ambient temperature. We also measured the levels of lipid peroxidation and glutathione content as markers of oxidative balance in cockroaches exposed to EMF. Our results showed that exposure to EMF for 24, 72 h and 7 days significantly increases the latency to escape from noxious heat. Malondialdehyde (MDA) levels increased significantly after 24-h EMF exposure and remained elevated up to 7 days of exposure. Glutathione levels significantly declined in cockroaches exposed to EMF for 7 days. These results demonstrate that EMF exposure is a considerable stress factor that affects oxidative state and heat perception in American cockroach.

In this paper, it is tested whether intermediate consumption of knowledge-intensive business services (KIBS) in the economy and technology advancement in the KIBS sector (measured by R&D expenditur...

The aim of this paper is to study and compare the importance of intermediate demand for financial services for the growth of production in the European Union countries. In the study the methodology introduced by Jorgenson et al. (1987) is used. This assumes that changes in the production (in real terms) result from changes in intermediate inputs of raw and manufacturing materials and services, as well as in factor inputs (labour and capital) and in total factor productivity. The advantage of this method is the ability to calculate the contributions of different components of intermediate inputs (including service inputs – total or with respect to particular service categories) to production growth in the whole economy and in individual industries. The study is carried out with respect to financial services, but their contribution to economic growth is compared with the contribution of knowledge--intensive business services that have been already recognized as affecting economic and productivity growth. The data used in the study come from the World Input-Output Database. The analysed period covers the years 1995–2009, owing to the availability of relevant data.

According to the three-sector model of economic growth, the development of a service economy is envisioned as a result of increasing consumer demand for various services, together with growing GDP per capita. However, technological progress has contributed to the structural transformation of economies based on knowledge, innovation and new technologies, which has been accompanied by increasing demand for services supporting production processes, in particular those related to new technologies and knowledge. As a result the dynamic development of a group of services called ‘knowledge-intensive business services’ (KIBS) can be observed, and they have become the main driving force behind the shift to the new service economy. A review of the literature demonstrates the growing interest in KIBS and their contribution to productivity growth and innovativeness. However, the research to date has explored these issues in a fragmented way, i.e. they have focused either on their impact on productivity or innovation performance, and in addition the ones referring to innovation are all based on micro data (for a given branch or group of branches, usually in one country). The present paper fills this gap, because it is the first comprehensive examination of the impact of KIBS on the competitiveness of different sectors that use these services in their business processes and on the competitiveness of the entire economy resulting from their impact on productivity and innovation. Due to the variety of definitions of KIBS used in the previous studies, this paper compares the impact resulting from KIBS usage in reference to both the broad and narrow definitions of KIBS thereof. The research also examines the relation between the intensity of KIBS usage within a domestic economy and the international competitiveness of its KIBS sector. It is also the first work in this field relating to the Polish economy, and the first one to compare the importance of KIBS for the development of the service economy, as well as the contribution of KIBS to the competitiveness of two groups of the EU countries which are at different levels of economic development: (1) Finland, Germany, Great Britain and Ireland – countries regarded as among the most competitive or most advanced in the development of a service economy in the EU; and (2) Czech Republic, Hungary, Poland and Slovakia – the Visegrad countries, which have undergone a similar path of transformation and integration with the EU. Studies conducted in the paper are based on data for each country coming from the same source (WIOD database, OECD STAN Database, WTO database, Eurostat Database), which ensures their comparability between countries. All studies are preceded by detailed theoretical foundations. Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00.

A lot of scientific publications are focused on the possible health effects of exposure to electromagnetic field. However, published results are often inconclusive and even contradictory and experimental conditions are not comparable. To formulate unambiguous conclusions they must rely on the results obtained using the same procedures and experimental conditions at different levels of organization within one model. In this paper we present an example of our experiments carried out on insects which are the most suitable for comprehensive study.

Electromagnetic fields (EMFs) are present throughout the modern world and are derived from many man-made sources including overhead transmission lines. The risks of extremely-low frequency (ELF) electromagnetic fields are particularly poorly understood especially at high field strengths as they are rarely encountered at ground level. Flying insects, however, can approach close to high field strength transmission lines prompting the question as to how these high levels of exposure affect behaviour and physiology. Here we utilise the accessible nervous system of the locust to ask how exposure to high levels of ELF EMF impact at multiple levels. We show that exposure to ELF EMFs above 4 mT leads to reduced walking. Moreover, intracellular recordings from an identified motor neuron, the fast extensor tibiae motor neuron, show increased spike latency and a broadening of its spike in exposed animals. In addition, hind leg kick force, produced by stimulating the extensor tibiae muscle, was reduced following exposure, while stress-protein levels (Hsp70) increased. Together these results suggest that ELF EMF exposure has the capacity to cause dramatic effects from behaviour to physiology and protein expression, and this study lays the foundation to explore the ecological significance of these effects in other flying insects.

The aim of this paper is to analyze and evaluate international trade in creative products with respect to the position of Poland in this exchange. In the introduction some definitions of creative industries and the concept of creative economy are presented. Then the classification of creative products in international trade and some problems with collecting data relating to international trade in creative products are discussed. In further work an empirical analysis of international trade in creative products is carried out. This work is divided into two parts. The aim of the first part is to indicate main tendencies and key players in international creative products exchange. The aim of the second part is to analyze the position of Poland in this exchange. The empirical analysis is based on the first database and report relating to international creative products exchange, published in 2008 by UNCTAD. Celem publikacji jest analiza międzynarodowego handlu produktami kreatywnymi, ze szczególnym uwzględnieniem pozycji Polski w tej wymianie. Na początku przedstawione są definicje kreatywnych produktów/ przemysłów oraz koncepcja gospodarki kreatywnej. Następnie omówiona jest klasyfikacja produktów kreatywnych w statystykach handlu międzynarodowego oraz problemy związane ze zbieraniem danych dotyczących międzynarodowego handlu produktami kreatywnymi. W dalszej pracy przeprowadzona jest analiza empiryczna międzynarodowej wymiany produktami kreatywnymi. Ta część pracy podzielona została na dwie części. Celem pierwszej części jest wskazanie głównych tendencji oraz najważniejszych uczestników międzynarodowej wymiany produktami kreatywnymi. Natomiast celem drugiej części jest analiza pozycji Polski w tej wymianie. Analiza empiryczna oparta jest na pierwszej bazie danych oraz raporcie dotyczących międzynarodowej wymiany produktami kreatywnymi, opublikowanych w 2008 roku przez UNCTAD.

Background Extremely low-frequency (50 Hz) electromagnetic field (ELF-EMF) is produced by electric power transmission lines and electronic devices of everyday use. Some phenomena are proposed as “first effects” of ELF-EMF: the discrete changes in the membrane potential and the increase of the calcium channel activity as well as the intracellular concentration of Ca 2+ . Interaction of the scorpion alpha toxin with the sodium channel depends on the orientation of the charges and may be perturbed by changes in the membrane polarization. The toxin induces overexcitability in the nervous system and an increase in the neurotransmitters released with different consequences, mainly the paralysis of muscles. We assumed that the exposure to ELF-EMF 0.7 mT will change the effects of the insect selective scorpion alpha toxin (recombinant LqhαIT from Leiurus quinquestriatus hebraeus) at the level of the cercal nerve function, the synaptic transmission and on the level of entire insect organism. Taking into account the compensatory mechanisms in organisms, we tested in addition ten times higher ELF-EMF on whole insects.Methods Experiments were performed in vivo on cockroaches (Periplaneta americana) and in vitro – on isolated cockroach abdominal nerve cord with cerci. In biotests, the effects of LqhαIT (10 −8 M) were estimated on the basis of the insect ability to turn back from dorsal to ventral side. Three groups were compared: the control one and the two exposed to ELF-EMF – 0.7 and 7 mT. Bioelectrical activity of the cercal nerve and of the connective nerve that leaves the terminal abdominal ganglion was recorded using extracellular electrodes. LqhαIT (5 × 10 −8 M) induced modifications of neuronal activity that were observed in the control cockroach preparations and in the ones exposed to ELF-EMF (0.7 mT). The exposure to ELF-EMF was carried out using coils with a size appropriate to the examined objects.Results The exposure to ELF-EMF (0.7 mT) modified the effects of LqhαIT (5 × 10−8 M) on activity of the cercal nerve and of the connective nerve. We observed a decrease of the toxin effect on the cercal nerve activity, but the toxic effect of LqhαIT on the connective nerve was increased. Biotests showed that toxicity of LqhαIT (10 −8 M) on cockroaches was reduced by the exposure to ELF-EMF (0.7 and 7 mT).Conclusions The exposure to 50 Hz ELF-EMF modified the mode of action of the anti-insect scorpion alpha toxin LqhαIT at cellular level of the cockroach nervous system and in biotests. Toxin appeared as a usefull tool in distinguishing between the primary and the secondary effects of ELF-EMF.

Experiments on the electromagnetic field influence on organisms are an important part of biophysical studies. It is an interdisciplinary research spanning biology and medicine with the engineering in generation and measurement of electromagnetic fields. The aim of the study consists the analysis of parameters estimations and measurements of extremely low frequency magnetic field (ELF MF) as well as exposure systems parameters in biomedical research.Experiments were performed on 2 most popular low magnetic field exposure systems: the solenoid and Helmholtz coils. A theoretical analysis and a measurement verification of the magnetic field distribution inside the systems were carried out to evaluate the homogeneity of the magnetic field. Additional factors, vibrations and temperature changes, affecting the assessment of the biological effects of magnetic field exposure were also examined.Based on the study results, a comparative analysis of solenoids and Helmholtz coils as the magnetic field exposure systems was presented. Proposals for the description of magnetic field exposure were also formulated.The authors emphasize the importance of a conscious choice of exposure conditions and their explicit description. These are fundamental requirements for both the reproduction of experiniental conditions and the verification of results.Badania nad oddziaływaniem pola elektromagnetycznego na organizmy żywe są istotnym elementem badań biofizycznych. Są to badania interdyscyplinarne, łączące nierozerwalnie biologię i medycynę z techniką wytwarzania i pomiaru pól elektromagnetycznych. Celem pracy jest analiza układów ekspozycyjnych pola magnetycznego ekstremalnie niskich częstotliwości w badaniach biomedycznych oraz metod pomiarów parametrów pola.Badaniom poddano 2 najpopularniejsze układy ekspozycyjne pola magnetycznego niskiej częstotliwości – solenoid i cewki Helmholtza. Przeprowadzono analizy teoretyczne i weryfikację pomiarową rozkładu pola w układach w celu oceny jednorodności pola. Zbadano również czynniki dodatkowe wpływające na ocenę biologicznych efektów ekspozycji – drgania i zmiany temperatury.Na podstawie przeprowadzonych badań przedstawiono analizę porównawczą solenoidów i cewek Helmholtza jako układów ekspozycyjnych pola magnetycznego oraz sformułowano wnioski dotyczące opisu warunków ekspozycji na pole magnetyczne.Autorzy podkreślają znaczenie świadomego doboru warunków ekspozycji i ich jednoznacznego opisu. Jest to podstawą odtworzenia warunków doświadczalnych oraz weryfikacji uzyskanych wyników. Med. Pr. 2015;66(2):185–197.

Celem artykulu jest zbadanie cech charakteryzujących dzialalnośc innowacyjną i innowacje w firmach uslugowych na podstawie wynikow badan Community Innovation Survey oraz proba oceny tych badan pod kątem ich skuteczności w ujmowaniu dzialalności innowacyjnej i innowacji w firmach uslugowych. W pierwszej cześci tekstu wskazano cechy uslug, ktore determinują charakter dzialalności innowacyjnej i modelu innowacji w firmach uslugowych. W dalszej jego cześci podjeto ich empiryczną weryfikacje na podstawie wynikow badan CIS dla wszystkich krajow UE. Uwzglednienie wszystkich krajow UE daje duzą liczbe obserwacji, a nalezy zauwazyc, iz dotychczasowe badania w tym obszarze prowadzone byly na podstawie danych dla pojedynczych krajow. Metodą badawczą jest porownanie dzialalności innowacyjnej firm przemyslowych i firm uslugowych w krajach UE, co pokazuje ewentualne roznice w charakterze dzialalności innowacyjnej firm z obydwu sektorow. Dzieki temu mozna odpowiedziec na pytanie, czy dzialalnośc innowacyjną firm uslugowych mozna badac za pomocą tych samych narzedzi, ktore stosowane są w firmach przemyslowych (podejście asymilacyjne), czy tez nalezy opracowac nowe metody pomiaru dzialalności innowacyjnej – (a) specyficzne dla firm uslugowych (podejście wyrozniające), czy (b) odnoszące sie jednocześnie do firm z obydwu sektorow (podejście integracyjne)

We show results of a project which focuses on detection of activity in neural tissue with Optical Coherence Tomography (OCT) methods. Experiments were performed in neural cords dissected from the American cockroach (Periplaneta americana L.). Functional OCT imaging was performed with ultrahigh resolution spectral / Fourier domain OCT system (axial resolution 2.5 μm). Electrical stimulation (voltage pulses) was applied to the sensory cercal nerve of the neural cord. Optical detection of functional activation of the sample was performed in the connective between the terminal abdominal ganglion and the fifth abdominal ganglion. Functional OCT data were collected over time with the OCT beam illuminating selected single point in the connectives (i.e. OCT M-scans were acquired). Phase changes of the OCT signal were analyzed to visualize occurrence of activation in the neural cord. Electrophysiology recordings (microelectrode method) were also performed as a reference method to demonstrate electrical response of the sample to stimulation.

In this pilot study we demonstrate results of structural Fourier domain OCT imaging of the nervous system of Periplaneta americana L. (American cockroach). The purpose of this research is to develop an OCT apparatus enabling structural imaging of insect neural system. Secondary purpose of the presented research is to develop methods of the sample preparation and handling during the OCT imaging experiments. We have performed imaging in the abdominal nerve cord excised from the American cockroach. For this purpose we have developed a Fourier domain / spectral OCT system operating at 820 nm wavelength range.

Celem publikacji jest analiza innowacyjności sektora usług na podstawie analizy danych wskazujących na znaczenia usług high-tech (zaawansowane technologicznie usługi nasycone wiedzą – HTKIS) w gospodarkach krajów Unii Europejskiej. W analizie uwzględniono takie dane jak wartość dodana, zatrudnienie, liczba firm, wielkość zysków i obrotów w sektorze HTKIS, jak również udział wartości dodanej i zatrudnienia w sektorze HTKIS w wartości dodanej i zatrudnieniu ogółem. Analizą objęte są lata 2003–2008/2009, ponieważ dla takiego okresu dostępne są dane dla Polski. W analizie porównywane jest również znaczenie sektora usług high-tech z sektorem przemysłowym high-tech oraz analizowany jest wpływ kryzysu i wpływ zmiany sposobu klasyfikacji działalności gospodarczych na rozwój i znaczenie sektora HTKIS w krajach UE. The goal of the publication was to analyze the innovativeness of the service sector on the basis of data analysis indicating the significance of high-tech services (knowledge-saturated advanced technological services – HTKIS) within the economies of the European Union. The analysis included data such as the value added, employment, number of businesses, profit sizes, and turnover in HTKIS, as well as the share of value added and employment in the HTKIS in value added and total employment. Included in the analysis are the years 2003–2008/2009 because data for Poland was available for this period. The study also compared the importance of the high-tech services sector to the high-tech industrial sector, and analyzed the impact of the crisis and change in the classification of economic activities for the development and importance of the HTKIS sector in the EU. Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00.

The aim of the study performed in the Department of Biophysics of Nicolaus Copernicus University is to investigate the effect of extremely low frequency electromagnetic field (ELF-EMF) exposure on animal nervous system function. American cockroach (Periplaneta americana) serves as a model in experiments. Insects are placed into the chamber inside the coil (electromagnetic field exciter) designed and manufactured by ,,Elektronika i Elektromedycyna Sp. J.”. Before starting the exposure it is necessary to determine: (1) what kind of field is applied, (2) the parameters of exposure and (3) the area of homogenous field. Only well established set-up characteristics can provide correct and comparable conditions of exposure to EMF. As well as, before starting the observation of the EMF influence on insects it is necessary to exclude factors which are associated with EMF exposure (such as temperature changes and vibrations) and could affect the organism function (behavior of animal). Especially cockroaches are very sensitive to vibrations and mechanical disturbances. Thermal conditions during the whole period of EMF exposure have been established earlier 1. The research that has been conducted by the authors so far included methodology of measurements of mechanical vibration spectrum and magnetic field distribution in interior part of electromagnetic field exciter on insects putted into research chamber. The vibration of electromagnetic field exciter occurs due to current flow by the exciter windings 2,3, and they acts on it in radial and longitudinal direction. In this paper the vibration and field distribution of field exciter measurements results are presented.