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Katarina Denac

Census of migrating raptors at Breginjski Stol (NW Slovenia) - the first confirmed bottleneck site in Slovenia

From 4 to 31 May 2010, raptor migration was monitored daily between 9.00 and 17.00 hrs CET at Breginjski Stol (NW Slovenia). In all, 2,385 raptor passes were counted, belonging to at least 17 species that were divided into resident and migratory birds. Residents (n = 875 passes) foraged, bred or daily migrated over the area. Among them, Griffon Vulture Gyps fulvus was the most frequent species (n = 575 passes) with the largest observed group of 35 individuals on 26 May. In the morning, Griffon Vultures were flying from west to east in search of food, whereas in the afternoon they were returning in the opposite direction to their colony in Forgaria nel Friuli (Italy). Their numbers increased after 15 May, when Croatian Griffons joined those from Italy. Altogether, 1,510 individuals of migratory raptors were counted, belonging to at least nine species. Among them, Honey Buzzard Pernis apivorus was the most common (1,368 ind., 90.6% of migratory raptors). The migration peak was reached on 14 May, with 552 individuals. Most raptors were seen migrating solitarily or in small flocks (2-4 ind.), whereas on five days (4, 7, 11, 13, 14 May) over 20% of all observed flocks were either medium-sized (5-15 ind.) or large (> 15 ind.). Raptors mostly migrated between 9.00 and 13.00 hrs. Taking into consideration several factors - short observation period and limited number of observation hours per day, overlooked raptors due to human- and topography-related causes, movements of observers between observation points, extremely bad weather and night migration of raptors - we estimate that the actual number of migratory raptors that passed Breginjski Stol in spring 2010 was 3,060-4,660 individuals. Thus, Breginjski Stol is the first confirmed bottleneck site of European importance for migratory raptors in Slovenia, as defined by BirdLife International IBA criterion B1iv, and a natural continuation of migratory pathways from northern Italy.

Open access

Dejan Bordjan and Luka Božič

. (1983): Žerjav Grus grus . - Acrocephalus 4 (17/18): 60. Štumberger, B. (1988): »Razvoj oblačnosti« pri močvirskih čigrah Chlidonias in nenaden pojav morske srake Haematopus ostralegus . - Acrocephalus 9 (35/36): 68-69. Štumberger, B. (1991): Pojavljanje jezerskega martinca Tringa stagnatilis v Sloveniji. - Acrocephalus 12 (48): 75-80. Štumberger, B. (1994): Popis ptic volčeških travnikov (Celje) in njihovo naravovarstveno ovrednotenje. - Acrocephalus 15 (65/66): 123

Open access

Małgorzata Popis

Abstract

Parkinson's disease is the second most common neurodegenerative disease, affecting about 0,15-0,3% of the world's population. Its characteristic feature is a loss of dopaminergic neurons in the substantia nigra. PD leads to dopamine deficiency and formation of intracellular inclusions called Lewy bodies, whose main ingredient is α-synuclein. Other types of nervous system cells are also affected by changes associated with that disease. The underlying molecular pathogenesis involves multiple pathways and mechanisms: mitochondrial function, oxidative stress, genetic factors, α-synuclein proteostasis, mitochondrial dynamic impairment, and disorders of the mitophagy process. This review summarizes the factors affecting the functioning of the mitochondria and their connection to the development of Parkinson's disease.

Open access

Małgorzata Popis, Blanka Borowiec and Maurycy Jankowski

Abstract

The common fruit fly, or Drosophila Melanogaster, has been used as an object of biomedicals studies for over a century. It has been mostly employed in genetic research, as it exhibits several advantages which make its use relatively easy and cheap, with the results widely translatable into further vertebrate studies. This model been the basis of the work of Christiane Nusslein-Volhard, who together with Eric Wieschaus unravelled much of the mystery surrounding early drosophila development in the 1970s-1980s, laying foundations for broader understanding of multicellular organism embryogenesis, which brought them a Nobel prize in Physiology and Medicine in 1995. The knowledge gained from drosophila studies improves the basic understanding of developmental processes, while the model itself is relatively easy to maintain, analyse and translate the results onto other species. While models such as Zebrafish present better with other vertebrates, drosophila remains a very important element of genetic research, finding even more applications with the development of current science and medicine. Hence, in this short review, the outline of the history, breakthroughs and perspectives of the drosophila research has been presented.

Open access

Magdalena Rojewska, Małgorzata Popis, Maurycy Jankowski, Dorota Bukowska, Paweł Antosik and Bartosz Kempisty

Abstract

Stem cells are cells that have the potential to replicate and/or differentiate, becoming any tissue. This process could be theoretically repeated indefinitely and can be used to create or fix damaged parts any organ. There are many in vivo factors that cause stem cells to replicate and differentiate. Many of these interactions and mechanisms are still unknown. In vitro models have been successful in inducing stem cells to differentiate into the desired lineage using controlled methods. Recently, epithelial tissue has been successfully created using scaffolds on which stem cells are grown in vitro and then transplanted into the host. This transition creates significant problems. This is because in vitro -grown stem cells or stem cell-derived tissues are created in an isolated environment where virtually every aspect can be monitored and controlled. In vivo monitoring and controlling is significantly more difficult for a plethora of reasons. Cells in the body are constantly exposed to many signals and molecules which affect them. Many of the mechanisms behind these interactions and reactions are known but many others are not. As the corpus of knowledge grows, stem cells become closer to being applied in a clinical setting. In this paper, we review the current evidence on stem cell therapy in regenerative medicine and some of the challenges this field faces.

Open access

Blanka Borowiec, Małgorzata Popis and Maurycy Jankowski

Abstract

A large amount of complex hormone associated processes occurring continuously in the human organism is necessary to maintain homeostasis in response to various internal and external conditions. In the same time, as the hormones use the bloodstream as their transmission medium, it is essential that their expression is strictly controlled to maintain their activity only when it is required. Because of that, the endocrine system evolved complex, self-regulating machinery that allows for precise signalling to the glands to initiate hormone expression, as well as equally quick negative feedback in the moment of reaching the optimal blood hormone concentration. The pituitary gland serves as the true endocrine part of that system, expressing a range of hormones that mostly serve as regulators of sub-systems serving different functions, scattered around organisms. The hypothalamus is the neuroendocrine part of the hypothalamic-pituitary axis, meaning it integrates the neuronal and hormonal signals, effectively linking the nervous and endocrine systems. The processes of hypothalamus and pituitary development share some significant similarities, which is unsurprising considering their close association and anatomical proximity at the base of the brain. Arising in highly overlapping developmental timeframes, they are both initially patterned by the gradients of extrinsic signalling molecules. After the initial lineage commitment, in both of those structures, intrinsic factors expressed by the distinct cell populations sustain the morphogenesis to result in a final complexly patterned structure. In this short review, the processes of the pituitary and hypothalamus development are described, with the most important factors driving them discussed.

Open access

Katja Logar and Luka Božič

Abstract

Between April 2007 and April 2008, 40 systematic waterbird counts were conducted on the Drava River between Lake Maribor and the Melje Dam (length 8.5 km, area 155 ha) to determine the specific composition, abundance and seasonal dynamics of bird occurrence. Between October and May, counts were conducted every week, whereas between June and September they were carried out once every two weeks. In total, 26,803 individuals of 30 species were counted. The number of waterbirds and diversity of species were the highest from late December to late February, when more than 1,000 individuals were regularly present in the area. Waterbirds were distributed along the river unequally, with the highest number of birds present yearround in the city centre and in the first counting sector of Lake Maribor. The Mallard Anas platyrhynchos and Mute Swan Cygnus olor were recorded during every count, while occurrence frequency was greater than 50% in another 10 species. Dominant species in terms of percentage composition were Mallard, Black-headed Gull Chroicocephalus ridibundus, Coot Fulica atra, Mute Swan, Pochard Aythya ferina and Tufted Duck Ay. fuligula. Mute Swan and Mallard were the only breeding waterbirds in the study area. Both the total number of waterbirds and the highest daily total in the first two counting sectors were greater between October and March 1992/93 than in our study. The decline in numbers was the greatest for Mallard, Pochard and Tufted Duck, while an increase was noted in Mute Swan and Yellow-legged / Caspian Gull Larus michahellis / cachinnans. The total number of waterbirds and the number of some species in the study area were significantly higher than expected solely based on its length compared to the length of the lowland Drava in Slovenia (125.7 km). The study area is conservationally important for Pochard, Tufted Duck and Black-headed Gull

Open access

Remo Probst, Larisa Bogdea, Dan S. Bandacu, Mirko Bohuš, Svilen Cheshmedzhiev, Ákos Gáborik, Siegfried Geissler, Calin V. Hodor, Dan T. Ionescu, Veselin Koev, Tibor Mikuska, Zsolt Nagy, Tibor Parrag, Vlatko Rožac, Matthias Schmidt, Thomas Schneider, Marko Šćiban, Sándor Tatai, Emil Todorov, Adrian Tomik, Marko Tucakov, Miklós Váczi and Georg Frank

Abstract

In January 2014, the first ever comprehensive winter census of the Whitetailed Eagle Haliaeetus albicilla along the Danube River was conducted, using mostly point and transect counts. Altogether, 550-700 eagles were counted. The upper range of the estimate may in fact be more realistic because 615 km of the Danube were not surveyed. Birds were observed in every country along the Danube. Hotspots of occurrences were (1) the Central Danube floodplains - the area encompassing the lower Hungarian section (Danube- Drava National Park), Kopački rit Nature Park (Croatia), and the Gornje Podunavlje Special Nature Reserve (Serbia); and (2) the Danube Delta Biosphere Reserve. According to the Action Plan for the conservation of the White-tailed Eagle along the Danube, future winter counts should be made regularly, and lower variation in the resulting eagle numbers achieved by a higher degree of synchronization between individual countries. This study reinforces the importance of protected areas along the Danube as a backbone for the conservation of White-tailed Eagles and biodiversity.

Open access

Athanasios Lamprakis, Kalliopi Alamani, Athina Malliari and Ilias Grivas

Abstract

Organisational justice is a key component in the practice of human resources management in any work environment. The aim of this research survey is to highlight the meaning and importance of organisational justice and its impact on employee engagement. To achieve this aim, except for the literature review, the survey examines the extent to which the distributive, procedural and interactional justice impact on work and organisational engagement, through a research in a certain Greek public organisation. As regards the statistical analysis of the research hypotheses, we used methods of the SPSS 17.00 statistical package. The results showed that the distributive justice significantly impacts on both types of engagement, while no effect was detected between procedural justice and the two types of engagement. The interactional justice was found to determine, partly, only the organisational engagement. The findings overwhelmingly verified the existing bibliographical references, resulting in a noteworthy empirical precedent which could contribute to the field concerning the impact that organisational justice exerts on certain aspects of organisational behaviour.

Open access

Marta Rybska, Sandra Knap, Katarzyna Stefańska, Maurycy Jankowski, Agata Chamier-Gliszczyńska, Małgorzata Popis, Michal Jeseta, Dorota Bukowska, Paweł Antosik, Bartosz Kempisty and Jędrzej M. Jaśkowski

Abstract

The superfamily of transforming growth factors β (TGF-β) consists of cytokines that are crucial in regulating the organism’s biological functions and includes three isoforms of TGF-β protein, Anti-Müllerian Hormone (AMH), inhibin A and B, activins, 20 bone morphogenetic proteins (BMP1-20) and 9 growth factors (GDF1-9). Their signal transduction pathway involves three types of membrane receptors that exhibit a serine/threonine kinase activity, as well as the Smad proteins. After ligand binding, the Smad proteins are phosphorylated and translocated to the nucleus, where they interact with transcription factors and affect gene expression. TGF-β family members are involved in cell growth and differentiation, as well as chemo-taxis and apoptosis, and play an important role during an inflammation. Defects in TGF-β proteins or in their signalling pathway underlie many severe diseases, such as systemic lupus, systemic scleroderma, bronchial asthma, atherosclerosis, hyperthyroidism or cancer. These factors are also crucial in mammal reproductive functions, as they are involved in folliculogenesis, steroidogenesis, ovulation, maternal-embryo interaction, embryo development and uterine decidualization. Their defects result in issues with fertility. This review focuses on the relevance of TGF-β family members in a mammal reproduction with an emphasis on three TGF-β isoforms, inhibins A and B, GDF-9 and their signal transduction pathway.