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Impact drop tests are routinely used to examine the dynamic performance of rockbolts. Numerous impact tests have been carried out in the past decades on independently designed, constructed and operated testing rigs. Each laboratory has developed testing procedures; thus, the results are often reported in different ways by various laboratories. The inconsistency in testing procedures and reporting formats presents a challenge when comparing results from different laboratories. A series of impact tests of identical rockbolts was carried out using the direct impact method (i.e. the mass free-fall method) on the rigs in four laboratories in different countries. The purpose of these tests was to investigate the level of consistency in the results from the four rigs. Each rig demonstrated a high level of repeatability, but differences existed between the various rigs. The differences would suggest that there is noticeable equipment-dependent bias when test results obtained from different laboratories are compared. It was also observed that the energy dissipated for the plastic displacement of the bolt was smaller than the impact energy in the tests. The average impact load (AIL) and the ultimate plastic displacement (D) of the bolt describe the ultimate dynamic performance of the bolt. In the case where the bolt does not rupture, the specific plastic energy (SPE) is an appropriate parameter in describing the impact performance of the bolt. Two other relevant parameters are the first peak load (FPL) and the initial stiffness (K) of the bolt sample. The information from this test series will guide the formulation of standardised testing procedures for dynamic impact tests of rockbolts.

The escape behaviour, measured as flight initiation distance (FID; the distance at which individuals take flight when approached by a potential predator, usually a human in the study systems), is a measure widely used to study fearfulness and risk-taking in animals. Previous studies have shown significant differences in the escape behaviour of birds inhabiting cemeteries and urban parks in European cities, where birds seem to be shyer in the latter. We collected a regional dataset of the FID of birds inhabiting cemeteries and parks across Latin America in peri-urban, suburban and urban parks and cemeteries. FIDs were recorded for eighty-one bird species. Mean species-specific FIDs ranged from 1.9 to 19.7 m for species with at least two observations (fifty-seven species). Using Bayesian regression modelling and controlling for the phylogenetic relatedness of the FID among bird species and city and country, we found that, in contrast to a recent publication from Europe, birds escape earlier in cemeteries than parks in the studied Latin American cities. FIDs were also significantly shorter in urban areas than in peri-urban areas and in areas with higher human density. Our results indicate that some idiosyncratic patterns in animal fearfulness towards humans may emerge among different geographic regions, highlighting difficulties with scaling up and application of regional findings to other ecosystems and world regions. Such differences could be associated with intrinsic differences between the pool of bird species from temperate European and mostly tropical Latin American cities, characterized by different evolutionary histories, but also with differences in the historical process of urbanization.

Background COVID-19 disease caused by SARS-CoV-2 coronavirus has affected millions of people worldwide. The mortality of this infection varies with age and comorbidities up to more than 10% in very elderly population. The aim of our study was to determine the disease pattern and mortality rate among multiple myeloma patients. Methods We retrospectively analyzed entries in the Czech Registry of Monoclonal Gammopathies from patients who were infected with SARS-CoV-2 from March 2020 until May 2021. Demographic data, treatment patterns, comorbidities, symptoms of COVID-19, treatment modalities and healthcare utilization was compared in survivors and non-survivors. Results Overall, 371 patients with MM and COVID-19 infection were identified. Median age at covid-19 diagnosis was 69 years (37-91 years), 53.4% (198/371) were males. There were 70.1% (260/371) survivors and 20.8% (77/371) deceased patients, outcome of 9.2% (34/371) of patients is unknown. PCR positivity was seen with median 20 days (1-84 days) in 79 evaluable patients. 6 patients were vaccinated prior to infection (5-68 days). Infection was acquired during actual treatment in 53.1% of patients (197/371). Median number of previous lines administered was 1 (0-7). Treatment preceding infection was most frequently composed of lenalidomide in 50.3%, bortezomib in 42.1% and daratumumab in 19.8%. Symptomatic infection was seen in 74.9% (278/371) of patients with fever being the leading symptom (49.6%) followed by cough (39.1%) and shortness of breath (35.0%). Inpatient treatment was needed in 45.0% (167/371) of patients, intensive care unit was required in 38.9% (65/167) of patients. Median length of in-hospital stay was 11 days (1-53 days). Artificial lung ventilation was necessary in 10.8% (18/167) patients, 24.6% (41/167) needed non-invasive ventilation or high flow oxygen and 35.3% (59/167) of patients needed low flow oxygen. Remdesivir was administered to 10.0% (37/371) and convalescent plasma to 4.9% (18/371) of patients. No difference was seen in mortality according to ISS stage (p=0.609), administered lines of therapy (p=0.119) or achieved treatment response (p=0.418). Conclusions The mortality of MM patients with COVID-19 was very high (20.8%). Healthcare utilization was high with almost half of the infected myeloma patients needing inpatient treatment. No apparent risk factors in terms of disease status or previous treatment were identified. Supported by MH CZ - DRO (UHHK, 00169906) and by the program PROGRES Q40/8.

The aim of this study was to explore different components of avian diversity in two types of urban green areas, parks and cemeteries, in four European countries in relation to environmental characteristics. We studied bird species richness, functional diversity and evolutionary distinctiveness in 79 parks and 90 cemeteries located in four European countries: the Czech Republic, France, Italy and Poland. First, we found no significant differences between cemeteries and parks in bird diversity. However, in both parks and cemeteries, only: two community metrics were affected by different environmental characteristics, including local vegetation structure and presence of human-related structures. Species richness was positively correlated with tree coverage and site size, functional diversity was unrelated to any of the measured variables, while the mean evolutionary distinctiveness score was positively correlated with tree coverage and negatively associated with the coverage of flowerbeds and number of street lamps. Our findings can be useful for urban planning: by increasing tree coverage and site size it is possible to increase both taxonomic richness and evolutionary uniqueness of bird communities. In both parks and cemeteries, the potential association between light pollution and bird species richness was negligible. We also identified some thresholds where bird diversity was higher. Bird species richness was maximized in parks/cemeteries larger than 1.4 ha, with grass coverage lower than 65%. The evolutionary uniqueness of bird communities was higher in areas with tree coverage higher than 45%. In conclusion, the findings of this study provide evidence that cemeteries work similarly than urban parks supporting avian diversity.

Urbanization is a permanent and still continuing expansion of human settlements and is responsible for dramatic changes of natural areas to urban areas. In traditional view, urbanization is often blamed for the loss of biodiversity and biotic homogenization of natural communities. However, for some species, urban areas, can represent suitable environment for life and even enable them to maintain stable and abundant populations. Urban ecosystems are not homogenous; within human settlements we can find several different habitats which can be occupied by species with different tolerance to certain aspects of urban life. This diversity can be exhibited by interhabitat changes in species richness, diversity and abundances of local communities. Here, we investigated biodiversity patterns in bird communities of two urban habitats, parks and cemeteries, in three Central European countries. Data on species richness, diversity and abundances of birds were collected from published papers as well as unpublished sources. Our analyses revealed that bird species richness was positively correlated with area and age of trees in both habitat types. There was however no significant relationship between species diversity and area in both habitat types. Moreover, species composition of bird communities significantly varied between cemeteries and parks with strong preference for one of habitat types in several species. Predominant occupancy of habitat type by certain species could be linked to interhabitat differences in vegetation structure, human behaviour and management. Interestingly, several bird species often recognised as urban avoiders were detected in surveyed cemeteries and parks.

Thermal embrittlement of high-chromium ferritic and martensitic steels at intermediate temperatures has been investigated in PM2000 (Fe20Cr) steel exposed to 475 °C by various non-destructive techniques, including magnetic Barkhausen noise (MBN), positron annihilation spectroscopy (PAS) and Mossbauer spectroscopy (MS). These techniques were used in a complementary manner to characterize the phase separation of the Fe-Cr ferrite phase into Fe-rich (α) and Cr-rich ferrite (α') phases, the phenomenon known as 475 °C embrittlement. Together with a reference steel T91, samples were subsequently isothermally annealed up to 750 h. While the MS technique clearly confirmed the formation of bcc Cr-rich precipitates in PM2000 steel with annealing time, the MBN and PAS techniques only indicated the formation of new pinning sites for magnetic domains and trapping sites for positrons in PM2000, up to 500 h annealing time, respectively. This observation was attributed to the precipitation process of Al-rich oxides in the oxide-dispersion strengthened PM2000 steel. This process, competitive to the chromium-rich α' phase precipitation, was found to be dominating the micromagnetic and positron-annihilation characteristics during the early stages of the annealing.