6 research outputs found
Tardigrades and oribatid mites in bryophytes from geothermally active lava fields (Krafla, Iceland) and the description of Pilatobius islandicus sp. nov. (Eutardigrada)
In polar regions, apart from tundra and glaciers, geothermally active areas
with elevated temperatures are important elements of ecosystems. One such geothermally
active region characterized by mosaic ecosystems and vast areas covered by recent lava
fields is Iceland. The aim of our study was to explore the diversity of invertebrates
inhabiting geothermally active lava fields in the Krafla area (Iceland). Eight bryophyte
samples were collected from a warm surface, mainly from the steaming areas. We have
found Nematoda, Rotifera, Tardigrada and Oribatida in the samples. Habitat analysis
demonstrated there to be 12 bryophyte species (five liverworts and seven mosses).
The diversity of bryophytes in a single sample ranged from one to six species. The
most common bryophyte was Racomitrium lanuginosum (Hedw.) Brid. Four species
of tardigrades were found, including one that was new. Pilatobius islandicus sp. nov.
is described herein by morphological, morphometric and molecular approaches (COI,
28S rRNA, 18S rRNA). Oribatida mites were identified as two species (Malaconothrus
monodactylus (Michael, 1888) and Camisia foveolata Hammer, 1955). The average density
of invertebrates was 13.1 ind./g with a maximum of 40.8 ind./g calculated per dry
material. The tardigrades found in our study belonged to herbivores, microbivores and
omnivores, whereas the mites belonged to saprophages, which indicates complex trophic
networks in geothermally active lava fields
Two additions to the moss flora of the South Shetland Islands in the maritime Antarctic
Tortella fragilis (Drumm.) Limpr. (Pottiaceae) and Bryum nivale Müll. Hal. (Bryaceae) are recorded for the first time from the South Shetland Islands in the northern maritime Antarctic. They were discovered in the Admiralty Bay area on King George Island, the largest island of this archipelago. The two species are briefly characterized morphologically, their habitats are described, and their distribution in the Antarctic is mapped. Discovery of these species has increased the documented moss flora of King George Island to 67 species, strengthening it in the leading position among individual areas with the richest diversity of moss flora in Antarctica. Likewise, T. fragilis and B. nivale represent remarkable additions to the moss flora of the South Shetland Islands, which currently consists of 92 species and one variety, making this archipelago by far the richest bryofloristically amongst large geographic regions of the Antarctic. Comparison of recent (2018) and old (1985) photographs revealed a significant retreat of glacial cover and suggests that the collection site was likely opened for colonization only within the last several decades. The record of T. fragilis is biogeographically relevant, and constitutes an intermediate site between the species’ occurrences in the Antarctic Peninsula and southern South America. The present record of B. nivale is the fourth discovery of the species worldwide, which may be helpful for the future designation of the distribution of this extremely rare species
Fine-scale spatial heterogeneity of invertebrates within cryoconite holes
Cryoconite holes (water-filled reservoirs) are considered ecologically simple ecosystems but represent biological hotspots of biodiversity on glaciers. In order to check for fine-scale spatial distribution of metazoans on the bottom of the holes, in this study, we analysed three groups of grazing invertebrates as a model: tardigrades, rotifers, and mites. We addressed differences within cryoconite holes comparing the distribution of invertebrates within and between separate holes and between glaciers at a worldwide scale. We divided each cryoconite hole into three sampling zones (established in relation to water flow on a glacier) and collected nine subsamples within cryoconite holes on glaciers in the Arctic (Longyearbreen), Norway (Blåisen), the Alps (Forni) and maritime Antarctic (Ecology Glacier). Generally, we found no consistent difference in sampling zones within cryoconite holes, which suggests homogeneity on the hole floors. However, we did find strong differences and high heterogeneity between subsamples, even within the same zone. Invertebrate densities ranged between 52 and 426 individuals per ml in subsamples collected from the same hole. We found from zero to four trdigrade species in the cryoconite hole on Longyearbreen. Our results show that benthic animals in cryoconite holes in various climatic zones have heterogeneous spatial distribution, even if no preference could be highlighted for upstream versus downstream areas with respect to water flow. The distribution of invertebrates may result from ecosystem disturbance by flushing water and animals’ active movement. Cryoconite holes, usually considered to be simple ecosystems, seem to be complex habitats where hidden spatial heterogeneity may affect abundance and diversity of organisms
Bezpośrednie i odległe wyniki leczenia guzów dołu podskroniowego i jego otoczenia z wykorzystaniem dostępu podskroniowego rozszerzonego
Background and purpose
The aim of the study was to present our results of the surgical treatment of subtemporal fossa tumours and surrounding regions using the extended subtemporal approach.
Material and methods
Twenty-five patients (10 women, 15 men) with subtemporal fossa tumours were included in the study. The neurological and performance status of the patients were assessed before and after surgery as well as at the conclusion of treatment. The approximate volume of the operated tumour, its relation to large blood vessels and cranial nerves, as well as consistency and vascularisation were assessed.
Results
The symptom duration ranged from 2 to 80 months (mean: 14 months). In 44% of patients, headache was the predominant symptom. Less frequent symptoms were: paralysis of the abducent nerve and disturbances of the trigeminal nerve. Approximate volume of the tumours ranged from 13 to 169 cm3 (mean: 66 cm3). The most frequent histological diagnosis was meningioma (16%), followed by angiofibroma, neurinoma and adenocystic carcinoma (12%). Total or subtotal resection was achieved in 80% of patients.
Conclusions
The extended subtemporal approach allows for the removal of tumours of the subtemporal fossa and surrounding regions. This approach also allows one to remove tumours expanding in the regions surrounding the subtemporal fossa only. In such cases the subtemporal fossa constitutes the way of the surgical approach.Wstęp i cel pracy
Celem niniejszej pracy jest przedstawienie własnych wyników leczenia operacyjnego guzów dołu podskroniowego i jego otoczenia z wykorzystaniem dostępu podskroniowego rozszerzonego.
Materiał i metody
Analizie poddano 25 przypadków guzów dołu podskroniowego, wśród których było 10 kobiet i 15 mężczyzn. Ocenie podlegał stan neurologiczny chorych przed rozpoczęciem leczenia, po operacji i po zakończeniu leczenia. Określano przybliżoną objętość operowanych guzów, ich stosunek do dużych naczyń i nerwów czaszkowych oraz konsystencję i stopień unaczynienia.
Wyniki
Długość wywiadu wahała się od 2 do 80 miesięcy i wynosiła średnio 14 miesięcy. W 44% przypadków wiodącym objawem był ból głowy. Rzadziej występowały niedowład lub porażenie nerwu odwodzącego oraz zaburzenia ze strony nerwu trójdzielnego. Przybliżona objętość usuniętych guzów wahała się od 13 do 169 cm3 i wynosiła średnio 66 cm3. Wśród usuniętych guzów najczęściej powtarzał się oponiak (16%). Rzadziej, bo w 12%, występowały naczyniakowłókniak, nerwiak i rak gruczołowo-torbielowaty. W 80% przypadków przeprowadzone resekcje były doszczętne lub z niewielkimi pozostałościami guzów.
Wnioski
Dostęp podskroniowy rozszerzony pozwala na usuwanie guzów dołu podskroniowego i graniczących z nim obszarów anatomicznych. Dostęp ten pozwala również na usuwanie guzów rozrastających się tylko w obszarach graniczących z dołem podskroniowym. W tych wypadkach dół podskroniowy stanowi drogę dostępu chirurgicznego
An unusual epiphytic habitat for hedwigia ciliata (Bryophyta: Hedwigiaceae) in Poland (central Europe)
In Poland, Hedwigia ciliata (Hedw.) P. Beauv., an obligatory epilithic moss species,
has in recent years also been observed on the bark of trees. In this paper, we
describe 25 recently identified sites in which epiphytic H. ciliata has been
observed, and provide a plausible explanation to account for this phenomenon