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A statistical shape model (SSM) based analysis was conducted in our study. We indicated the morphological differences of the first trapezoid-metacarpal (TMC) bone between the region-based statistical shape model (rSSM) and the nonregion-based statistical shape model (nrSSM). We aimed to characterize more specific and accurate variation results to detect and prevent osteoarthritis in an early way. CT image data of TMC from 31 healthy volunteers were simulated with 3D models. A training set of models was analyzed with principal component analysis, with both then- rSSM and rSSM. The region was identified automatically with Gaussian curvature analysis. We found four dominant shape variations from both nrSSM and rSSM. The rSSM showed more variations with fewer components compared with nrSSM. The first principal component revealed the size variation as the biggest component. A significant difference was presented in the second and the fourth principal component from rSSM, showing the torsion of the distal head of the first metacarpal which may increase the risk of osteoarthritis.

The objective of the present work was to evaluate the surface wettability of commercially available polymeric protective gloves, as well as to determine the effects of their surface topography in conjunction with the glove material on the hydrophobic properties of the final products, together with surface free energy (SFE) and work of adhesion.

The diversity, distribution and ecology of aquatic Tardigrada in Poland remain poorly known. We reviewed the literature focused on tardigrades in Poland and recognized only 15 aquatic taxa which were reported from various freshwater and marine habitats. Among them, 12 are freshwater and three are marine taxa. Hypsibius dujardini is Poland’s most widely-distributed hygrophilous species, but it re presents rather a complex of cryptic species and their diagnosis requires integrative approaches. Most reports of aquatic tardigrades in Poland are accidental findings mostly from water bodies in Tatra Mountains or from lakes in Masurian Lake District. Some species were also reported from small ponds or wastewater treatment plants in other regions like Małopolska or Wielkopolska Provinces.

This study concerns the creep impact on strength parameters of the selected very cohesive soils (PI = 30–70%). The analysis refers to Neogene clays characterized by a complex structure, resulting directly from a complicated load history in the geological time scale and identified glacitectonic deformations. In the process of samples’ preparation for strength tests as well as during the interpretation of the post-failure state, particular attention was paid to the soil structure. The imaging methods (X-ray densitometry and computer microtomography) enabled the comparison of the soil structure and the selection of samples with similar characteristics. The completed program of strength tests consisted of two series of tests in the triaxial stress state, differentiated by the occurrence of the initial creep stage, preceding the typical strength test scheme under undrained conditions. This study allowed to obtain a quantitative assessment of the influence of the creep process on the strength parameters of tested soils. Constant stress lower than 60% of the shear stress deviator leads to the deceleration creep course (m parameter 0.64–0.89). As a result, higher values of internal friction angle (20% increase comparing to triaxial tests without creep stage) and cohesion reduction are obtained from triaxial creep tests. Creep parameter m is found to be a valuable indicator for differentiation of landslide activity trend. The tests proved low values of axial strains (1–5%) at failure, which was associated with lithogenesis. By the implementation of obtained strength parameters into the 3D finite element model of the slope, the potential influence of the creep process on the stability of an exemplary cross section of the Warsaw slope could be determined.

The dynamic development of the world economy entails an increasing exchange of goods and population. This means that we are globally struggling with increasing levels of nosocomial infections. The increasing use of antimicrobial agents triggers the microorganisms’ immune system, which in turn contributes to the increasing amount of antibiotic-resistant microorganisms, making it necessary to control the development of unwanted microorganisms, including bacteria, especially those carried on the body and clothing.

Spatial graphene is a 3D structure of a 2D material that preserves its main features. Its production can be originated from the water solution of graphene oxide (GO). The main steps of the method include the crosslinking of flakes of graphene via treatment with hydrazine, followed by the reduction of the pillared graphene oxide (pGO) with hydrogen overpressure at 700 °C, and further decoration with catalytic metal (palladium). Experimental research achieved the formation of reduced pillared graphene oxide (r:pGO), a porous material with a surface area equal to 340 m2/g. The transition from pGO to r:pGO was associated with a 10-fold increase in pore volume and the further reduction of remaining oxides after the action of hydrazine. The open porosity of this material seems ideal for potential applications in the energy industry (for hydrogen storage, in batteries, or in electrochemical and catalytic processes). The hydrogen sorption potential of the spatial graphene-based material decorated with 6 wt.% of palladium reached 0.36 wt.%, over 10 times more than that of pure metal. The potential of this material for industrial use requires further refining of the elaborated procedure, especially concerning the parameters of substrate materials. [ABSTRACT FROM AUTHOR]

In this paper, samples of mosses, lichens and cryptogams (mosses mixed with lichens) collected from Słowiński National Park (northern Poland) were studied for water bears (Tardigrada). In total, 27 tardigrade taxa were identified: 21 to the species level, one identified as „cf." and three to the genus level, with six species (Eremobiotus ginevrae, Hypsibius dujardini, Hypsibius scabropygus, Milnesium beasleyi, Minibiotus intermedius and Notahypsibius pallidoides) being new records for Poland. Two possibly new for science species were also found, belonging to genera Diphascon and Mesobiotus. Additionally, a very rare eutardigrade Pseudohexapodibius degenerans has been found in the samples analyzed in the present study for the first time outside of the type locality. The effects of habitat and substrate on species richness were also investigated and showed no significant differences between mosses and lichens, as well as all substrates except for concrete walls. [ABSTRACT FROM AUTHOR]

Perchlorate salts, including magnesium perchlorate, are highly toxic compounds that occur on Mars at levels far surpassing those on Earth and pose a significant challenge to the survival of life on this planet. Tardigrades are commonly known for their extraordinary resistance to extreme environmental conditions and are considered model organisms for space and astrobiological research. However, their long-term tolerance to perchlorate salts has not been the subject of any previous studies. Therefore, the present study aimed to assess whether the tardigrade species Paramacrobiotus experimentalis can survive and grow in an environment contaminated with high levels of magnesium perchlorates (0.25–1.0%, 1.5–6.0 mM ClO4− ions). The survival rate of tardigrades decreased with an increase in the concentration of the perchlorate solutions and varied from 83.3% (0.10% concentration) to 20.8% (0.25% concentration) over the course of 56 days of exposure. Tardigrades exposed to 0.15–0.25% magnesium perchlorate revealed significantly decreased body length. Our study indicates that tardigrades can survive and grow in relatively high concentrations of magnesium perchlorates, largely exceeding perchlorate levels observed naturally on Earth, indicating their potential use in Martian experiments. [ABSTRACT FROM AUTHOR]

This paper presents the impact of selected essential aspects of geological structure on the state of slope stability as assessed by changes in the safety factor (SF). The engineering geological slope features that were analysed include: (i) changes in soil cohesion and internal friction angle, (ii) presence of a weak soil layer and its span, (iii) structural discontinuity (i.e. fault), (iv) soil permeability properties and water conditions (i.e. groundwater level, long and heavy rainfall). A certain scheme of slope stability calculations has been proposed for a case involving complex geological conditions. The numerical modelling of a hypothetic slope was performed using the shear strength reduction method based on the finite element method.

The aim of this study was the evaluation of the relationship between the presence of tardigrades and various levels of sewage pollution in different tanks of a wastewater treatment plant. The study was carried out in the wastewater treatment plant located near Poznań (Poland) during one research season. The study was conducted in a system consisting of three bioreactor tanks and a secondary clarifier tank, sampled at regular time periods. The presence of one tardigrade species, Thulinius ruffoi, was recorded in the samples. The tardigrades occurred in highest abundance in the tanks containing wastewater with a higher nutrient load. Thulinius ruffoi was mainly present in well-oxygenated activated sludge and its abundance was subject to seasonal fluctuations; however, its preference for more polluted tanks seems to be consistent across the year. Although more detailed experimental study is needed to support the observations, our data indicate that T. ruffoi has a high potential to be used as a bioindicator of nutrient load changes.

This article presents the results of petrophysical analyses of limestones and sandstones used for the construction of the wall structures of a Roman rural settlement located in Podšilo Bay on Rab Island (Croatia). An on-site analysis of the walls indicated the use of different lithotypes, which is an uncommon case in the area. So far, no petrophysical properties of the applied materials have been tested, and their provenance has not been specified. The aim of this research was to determine their usability as construction materials in an attempt to determine the possible reasons behind the usage of multiple lithotypes and their suitability as building materials. The following procedure was used to address these issues: (1) determination of the petrographic characteristics of the rocks, (2) performance of tests to characterise the mechanical properties in a complex stress state of uniaxial tension followed by uniaxial and triaxial compression, and, finally, (3) determination of the internal structure of the rocks using methods based on X-ray imaging. Multi-proxy characteristics of the materials including numerous observations and methods were performed: optical microscopy used to characterise rock petrography and mineralogy, scanning electron microscopy (SEM) coupled with EDS, as well as grinding tests; furthermore, mechanical properties were determined on cylindrical samples in accordance with European standards. X-ray microtomography using the XμCT method enabled microscopic observations and determination of the orientation of discontinuities and the rock structure. The performed analyses allowed us to distinguish three lithological types of sandstone and two types of limestone among the examined stone blocks. Stone blocks of fine- and medium-grained sandstone with carbonate binders, as well as sparitic limestone and mudstone with calcite veins, were used to build the studied structures. The analysed blocks showed traces of partial edge processing. Despite the defects in the material structure identified using XμCT, all the types of rock were characterised by high or very high strength. High values of longitudinal wave velocity confirmed the good quality of the material. These results contribute to a better understanding of the construction process and the related technological choices, and they provide the first dataset which can be used for the reconstruction of the building's original appearance in the future. [ABSTRACT FROM AUTHOR]

Many vertebrates, both homeo- and poikilothermic, show a significant relationship between body size and environmental temperature. Whether such an association may exist in microscopic invertebrates has been less explored. Therefore, we decided to analyse terrestrial Tardigrada from various habitats worldwide to examine whether these animals reveal any relationship pattern between body size and environmental temperature. Data on minimum, maximum, and mean body sizes were extracted from original descriptions or sometimes from later re-descriptions of the species. Minimum, maximum, and mean temperature data from the type localities of the species were retrieved from WorldClim 2. In general, accounting for geographic and phylogenetic confounding factors, the body size of terrestrial tardigrades decreased as the environmental temperature increased. The same tendency was observed for most of the genera when additional analyses were carried out separately for each genus. This is the first biogeographical analysis demonstrating that terrestrial tardigrades generally conform to the temperature–size rule. [ABSTRACT FROM AUTHOR]

The genera Xerobiotus and Pseudohexapodibius are xerophilic and characterized by reduced appendages and claws as adaptations to move between small interstices. To increase the knowledge of their biodiversity, biogeography and phylogeny, several specimens from European countries and Australia were analysed using an integrative approach, i.e. morphological, karyological and molecular studies (18S, 28S, cox1 , cytb and ITS2). The phylogenetic position of Xerobiotus with respect to the three evolutionary lineages of Macrobiotus remains unchanged with respect to what was previously identified in the phylogeny of Macrobiotidae. The following new Xerobiotus species are described: Xerobiotus litus sp. nov. Xerobiotus arenosum sp. nov. and Xerobiotus reductus sp. nov. It is proposed that Macrobiotus naginae should be transferred to Xerobiotus (Xerobiotus naginae comb. nov.). Pseudohexapodibius degenerans clusters within Xerobiotus and shares morphological and genetic characters with this genus. Some discrepancies between genetic and phenotypic data are found among the analysed species. Even between the results obtained with analysed genes disagreements are found, with cox1 and cytb generally agreeing with phenotypic results more than ITS2. Genotypic and phenotypic data are useful tools for species identification, but they have to be evaluated critically to obtain reliable results. [ABSTRACT FROM AUTHOR]

Tardigrades are common in many terrestrial environments and habitats. Although little is known on their ecological preferences, previous studies found diversity and community composition significantly affected by various variables. This study associated tardigrade species' records with climatic variables, forest type, and substrate categories exploring tardigrade diversity and species communities to find associations with ecological characteristics of Norwegian forests. A total of 17 473 specimens were identified, encompassing 131 species (including putatively new species) from 305 samples of different substrates (leaf litter, bryophytes, and lichens). Bryophytes and lichens of samples were classified according to the main species, and growth form, and associated with tardigrade species and sample metadata. Tardigrade species' richness was related to climatic variables and forest type, increased with precipitation, decreased with summer temperature, and not varied with precipitation seasonality. Although there was an unbalanced representation of substrate categories in the different forest types, some tendencies were detectable. Mixed oak and birch forests reached the highest species' richness. Tardigrade community composition varied between substrate categories and, to a lesser degree, between forest types, but not with climatic variables. Our study highlights the importance of large-scale variables on tardigrade diversity, and substrate categories for tardigrade community composition. [ABSTRACT FROM AUTHOR]

Professor Barbara Węglarska, a renowned Polish scientist, made significant contributions to the fields of tardigrade physiology, morphology, taxonomy, and faunistics. Despite her education being interrupted by World War II, she later earned her M.Sc. and Ph.D. degrees. Throughout her career, she published numerous research articles and co-authored a textbook on insect developmental biology. Professor Węglarska organized an international symposium on tardigrades and received several state medals for her contributions to science and higher education in Poland. She passed away in 2020 at the age of 98, leaving behind a scientific legacy of groundbreaking studies on tardigrades and advancements in taxonomy and faunistics. Colleagues remember her passion for research and mentorship. [Extracted from the article]

Perchlorates are present at high concentrations in Martian regolith and pose an additional challenge to the survival of terrestrial life on Mars. Some microinvertebrates can resist extreme conditions (e.g. low temperatures, lack of oxygen and radiation), making them suitable model species for space experiments. Clarification of whether they can tolerate high levels of perchlorates is crucial for understanding the scope of application of small invertebrates in Mars exploration. We assessed the activity of some Crustacea, Nematoda, Rotifera and Tardigrada exposed to 0.25–1.00% magnesium perchlorate. The number of active specimens decreased with exposure time and perchlorate concentration. However, exposure of selected species to 0.25% perchlorate for 24 or 72 h showed activity in some specimens. Only Caenorhabditis elegans , Lecane inermis and Artemia salina exhibited activity after 24 h exposure to 1.00% perchlorate. Lecane inermis was the only species to remain active after 72 h of incubation with 1.00% perchlorate. Transferring specimens to distilled water after perchlorate exposure generally resulted in high recovery rates. The study indicates that all the tested invertebrates resist extremely high concentrations of perchlorates, which has implications for further research on their potential use in development of biological systems with improved performance and utility on Mars. [ABSTRACT FROM AUTHOR]

Tardigrada (water bears) are a group of small invertebrates known for their ability to survive extreme desiccation by entering an anhydrobiotic state. This state is characterized by the loss of ≤ 98% of body water, resulting in body shrinkage and almost complete cessation of metabolism. In anhydrobiosis, multiple mechanical and biochemical stress effects, such as protein denaturation and aggregation, DNA damage, formation of reactive oxygen species, membrane disintegration and degeneration of cellular compartments, are counteracted by various proteins. Although multiple studies of individual proteins and tardigrade proteomes have been conducted, our knowledge of tardigrade anhydrobiosis-related proteins has not yet been reviewed. To fill this gap, based on available papers, we present a review of all tardigrade proteins known to contribute to desiccation survival, including intrinsically disordered proteins, heat shock proteins and reactive oxygen species-scavenging enzymes. Although proteins are the major anhydrobiosis-related factors in tardigrades, many questions regarding the role of the tardigrade proteome in anhydrobiosis remain unanswered. [ABSTRACT FROM AUTHOR]

Recently it was purported that autofluorescence (AF) in Paramacrobiotus n. sp. provided protection from UV radiation. If true, this would be the first documentation of an adaptive function for AF in any microscopic animal. We review what is currently known about AF in tardigrades, and we provide the first true colour images of tardigrade fluorescence. To assess the hypothesis of AF as UV protection we measured interspecific variation and intraspecific variation. We found that interspecific variation was much greater than intraspecific variation. We compared the fluorescence emission spectra for nine species of tardigrades, and together with the true colour fluorescence images, we noticed different patterns of fluorescence suggesting a rich diversity of fluorophores. We examined epidermal pigments of a new species of Milnesium and Ramazzottius kretschmanii and found that they are not the source of fluorescence in these species. We suggest further research is necessary to test the hypothesis that AF is UV protective in tardigrades, and we demonstrate and assess four different research tools for examining autofluorescence in microscopic animals. [ABSTRACT FROM AUTHOR]

The study employs numerical calculations in the characterization of reservoir sandstone samples based on high-resolution X-ray computed microtomography. The major goals were to determine porosity through pore size distribution, permeability characterization through pressure field, and structure impact on rock strength by simulation of a uniaxial compression test. Two Miocene samples were taken from well S-3, located in the eastern part of the Carpathian Foredeep. Due to the relation between sample size and image resolution, two X-ray irradiation series with two different sample sizes were performed. In the first approach, the voxel side was 27 μm and in the second it was up to 2 μm. Two samples from different depths have been studied here. Sample 1 has petrophysical features of conventional reservoir deposits, in contrast to sample 2. The approximate grain size of sample 1 is in the range 0.1-1.0 mm, whereas for sample 2 it is 0.01-0.1 mm with clear sedimentation lamination and heterogenic structure. The porosity, as determined by μCT, of sample 1 is twice (10.3%) that of sample 2 (5.3%). The equivalent diameter of a majority of pores is less than 0.027 mm and their pore size distribution is unimodal right-hand asymmetrical in the case of both samples. In relation to numerical permeability tests, the flow paths are in the few privileged directions where the pressure is uniformly decreasing. Nevertheless, there are visible connections in sample 1, as is confirmed by the homogenous distribution of particles in the pore space of the sample and demonstrated in the particle flow simulations. The estimated permeability of the first sample is approximately four times higher than that of the second one. The uniaxial compression test demonstrated the huge impact of even minimal heterogeneity of samples in terms of micropores: 4-5 times loss of strength compared to the undisturbed sample. The procedure presented shows the promising combination of microstructural analysis and numerical simulations. More specific calculations of lab tests with analysis of variable boundary conditions should be performed in the future.

Even for tardigrades, often called the toughest animals on Earth, a hypomagnetic field (HMF) is an extreme environment. However, studies on the effect of HMF on tardigrades and other invertebrates are scarce. Mitochondria play an important role in an organism's response to extreme conditions. The effect of HMF on the mitochondrial inner membrane potential (Δψ), a well-known marker of mitochondria functionality, shows that mitochondria are very sensitive to HMF. Tomeasure the HMF effect on Paramacrobiotus experimentalis,we calculated the tardigrade survival rate and Δψ level after HMF treatments of different durations. We also estimated the relationship between the age and sex of the tardigrade and the HMF effect. We observed age- and sex-related differences in Δψ and found that Δψ changes after HMF treatmentwere dependent on its duration aswell as the animal's age and sex. Furthermore, active P. experimentalis individuals displayed a high survival rate after HMF treatment. The data may contribute to the understanding of tardigrade aging and their resistance to extreme conditions including HMF, which in turn may be useful for future space explorations. [ABSTRACT FROM AUTHOR]

Paramacrobiotus species have been described in almost every corner of the world. To date, 45 species have been reported from this genus. Among which, 13 belong to the areolatus group (without a microplacoid) and 32 belong to the richtersi group (with a microplacoid). The species' presence in different climatic conditions and habitats provides evidence of their adaptation to various harsh environments. The species of the genus are both bisexual (diploid) and parthenogenetic (triploid). The bisexual species have external fertilization. And they are omnivorous whose diet consists of certain cyanobacteria, algae, fungi, rotifers, nematodes and juvenile tardigrades. The life history of species from this genus varies from species to species. Because the species has a strong predilection for cryptobiosis, numerous investigations involving anhydrobiosis have been conducted utilizing specimens from varied Paramacrobiotus species to date. In this review, we provide a concise summary of changes observed due to various cryptobiotic conditions in many species of this genus, the geographical distribution of all the species, feeding behaviour, life history, microbiome community, Wolbachia endosymbiont identification, reproduction, phylogeny and general taxonomy of the species from the genus Paramacrobiotus. Furthermore, we provide a new diagnostic key to the genus Paramacrobiotus based on the morphological and morphometric characters of adults and eggs. [ABSTRACT FROM AUTHOR]