1,116 research outputs found
A powerful computational crystallography method to study ice polymorphism
Classical Molecular Dynamics (MD) simulations are employed as a tool to
investigate structural properties of ice crystals under several temperature and
pressure conditions. All ice crystal phases are analyzed by means of a
computational protocol based on a clustering approach following standard MD
simulations. The MD simulations are performed by using a recently published
classical interaction potential for oxygen and hydrogen in bulk water, derived
from neutron scattering data, able to successfully describe complex phenomena
such as proton hopping and bond formation/breaking. The present study
demonstrates the ability of the interaction potential model to well describe
most ice structures found in the phase diagram of water and to estimate the
relative stability of sixteen known phases through a cluster analysis of
simulated powder diagrams of polymorphs obtained from MD simulations. The
proposed computational protocol is suited for automated crystal structure
identification.Comment: RevTex 4.1, 7 figures - to be published in the Journal of Chemical
Physic
First conclusions about results of GPR investigations in the Church of the Assumption of the Blessed Virgin Mary in KĹ‚odzko, Poland
Abstract. The article presents results of a ground penetrating radar (GPR) investigation carried out in the Church of the Assumption of the Blessed Virgin Mary in Kłodzko, Poland, dating from the 14th to 16th centuries. Due to the 20th century wars, the current state of knowledge about the history of the church is still poor. Under the floor of the Catholic temple, unknown structures might exist. To verify the presence of underground structures such as crypts and tombs, a GPR survey was carried out in chapels and aisles with 500 and 800 MHz GPR shielded antennas. Numerous anomalies were detected. It was concluded that those under the chapels were caused by the presence of crypts beneath the floor
Impact of Horse Grazing on Floristic Diversity in Mediterranean Small Standing-Water Ecosystems (SWEs)
Small standing-Water Ecosystems (SWEs), despite their pivotal ecological role due to their participation in hydrogeological processes and their richness in biodiversity, seem to be often overlooked by the scientific community. In this study, the vascular plant diversity in some representative SWEs, that host a peculiar assemblage of plant and animal species, was investigated in relation to the disturbance effects of a wild horse population. A total of 50 plots, equally distributed in small and large SWEs, were surveyed and a level of disturbance was attributed to each plot. We found greater species richness in small and undisturbed SWEs, which suggests the negative impact of horse grazing on the richness of plant species in this type of habitat. Significant differences in plant assemblage were found according to the disturbance level, whereas, contrary to what was observed for species richness, no differences were detected based on their size. The diversity indices, used to evaluate the richness and diversity in these areas, recorded the highest values for small and undisturbed areas. This result highlights that the disturbance of the horse grazing plays a pivotal role in affecting the diversity and richness of species in the SWEs. These findings suggest that SWE systems should be analyzed considering these areas as unique in order to allow the conservation of the plant richness and biodiversity of the SWE systems in conjunction with the protection of horses
An eco-physiological and biotechnological approach to conservation of the world-wide rare and endangered aquatic liverwort Riella helicophylla (Bory et Mont.) Mont.
The rare aquatic liverwort Riella helicophylla (Bory et Mont.) Mont., inhabitant of temporary shallow ponds around the Mediterranean basin, is considered threatened throughout its distribution range. In addition, little is known of its biology and ecology or of its role in such an important ecosystem where envi- ronmental conditions vary yearly in unpredictable ways. In these variable habitats, due to the seasonal fluc- tuation of water levels, there is no guarantee of yearly spore input into the spore bank. Spore germination rate and the effects of different culture media in an axenic culture establishment, as well as propagation proce- dures of R. helicophylla, were tested. New insights into the ecology and biology of R. helicophylla are given. Spore dormancy is documented, and the protocols for the in vitro culture establishment, propagation and ac- climatization of this liverwort are developed. Dry storage at 20 ± 2 °C for about three months broke the dor- mancy of spores, which subsequently germinated in a high percentage (over 90%). A two phase (solid and liquid) culture media system was developed for the purpose of achieving fully developed gametophytes. The liquid phase contained electrolytes simulating brackish water
Contribution to the bryological knowledge of the Tuscan-Emilian Apennines (Northern Italy)
The inventory of the bryophytes collected during the annual excursion of the Working Group for Bryology of the Italian Botanical Society is reported. This excursion was held in 2018 on the northern slope of the Tuscan-Emilian Apennines National Park, in the Administrative Region of Emilia-Romagna. The field work led to the finding of 113 taxa (24 liverworts and 89 mosses), including eight new records and seven confirmations for this Region. The occurrence of rare taxa for Italy (Scapania uliginosa, Rhizomnium pseudopunctatum, Racomitrium fasciculare, Scorpidium cossonii, Grimmia lisae, Orthotrichum pulchellum) is highlighted
On the stability of the dorsal pattern of European cave salamanders (genus Hydromantes)
Photographic identification is an emerging method for recognising wild animals. This harmless methodology allows researchers
to identify \u201cnaturally marked\u201d individuals and therefore study their specific ecology and behaviour. However, before incurring
potential data loss, it is recommended to test the methodology on the target species and evaluate the pros and cons. We assessed the reliability of photographic identification in adult Hydromantes salamanders from three species. Specifically, we assessed whether the dorsal pattern of adult salamanders changed over time, thus evaluating its potential use as a reliable marking methodology. We used capture-mark-recapture and controlled conditions (i.e. individuals kept in fauna boxes) to evaluate potential changes in the dorsal pattern of Hydromantes through time. We did not observe any change in the dorsal pattern in the three species during the study period. Photographic identification might be a useful marking technique for these endangered species. However, these animals are usually found in environments generally lacking light and thus, researchers must be careful in setting up proper light conditions to produce suitable pictures for individual identification of Hydromantes
Importance of plants with extremely small populations (Psesps) in endemic-rich areas, elements often forgotten in conservation strategies
The distribution of the threatened fern Ophioglossum vulgatum L., a plant with extremely small populations (PSESPs) in Sardinia, is characterized by small disjunct populations with only a few individuals, and little is known about its status in the wild. To provide information for the conservation of O. vulgatum and with the aim to develop an in situ conservation strategy, we investigated its distribution, population size, and habitat. Field surveys confirmed that the species grows in only five localities. Two representative populations were selected for this study (Funtanamela and Gedili), and in each population, all plants were mapped and monitored monthly from April to August over an 8-year period. During the study, the populations had a very low number of reproductive plants and the populations appeared to be in decline, with the total number of plants per population slightly decreased in Gedili while a sharp reduction was recorded in Funtanamela due to wild boar threat. A fence was built in order to protect the site from further damage, but no noticeable signals of recovery were observed. The most urgent conservation requirement for this species is to preserve the threatened habitat of the remnant populations. Further field surveys and research are also required for an improved understanding of the species’ status
PREVALENCE AND CHARACTERIZATION OF LISTERIA MONOCYTOGENES ISOLATED FROM DIFFERENT FOOD PRODUCTS
During the period 2006-2009, 453 samples of various food products were collected and analyzed for Listeria monocytogenes. In order to increase the knowledge of the ecology and epidemiology of this organism, isolates were characterized by serotyping, and PCR for the presence of the main virulence-associated genes and genetic relatedness
Translocations of threatened plants in the Mediterranean Basin: current status and future directions
The Mediterranean Basin is one of the World's plant diversity hotspots and a region prone to several anthropic pressures, besides being one of the World's areas most susceptible to climate change. In this region, which hosts a high percentage of threatened species, there has been a large increase in practical conservation actions to prevent the extinction of many plants or improve their conservation status. In this framework, plant translocations have become increasingly important. To obtain a picture of the status and to depict possible directions, data on plant translocations was collected through the available databases, national experts, and the grey literature available online. Overall, a list of 836 translocations relating to 572 plant species was found. These actions are mainly concentrated in Spain, France, and Italy (c. 87%) and, except for some pioneering actions, translocations have strongly increased starting from 2010. A subsequent in-depth bibliographic search of the scientific databases was conducted to determine how much information about plant translocations was documented in the scientific literature. This search resulted in a list of 133 peer-reviewed papers, of which only 17 describing one or more translocations and, as a whole, reporting 101 experiences carried out on 56 plant species. Our research highlighted a great discrepancy between the scarce scientific documentation in comparison to the large number of practical conservation actions carried out. The great experience gained in these translocations constitutes an enormous heritage potentially available to implement the necessary conservation actions to preserve the plant diversity of the Mediterranean Basin
Global and Regional IUCN Red List Assessments: 15
In this contribution, the conservation status assessment of three vascular plants are presented according to IUCN categories and criteria. It includes the assessment of Oryza rhizomatis D.A.Vaughan and Saxifraga facchinii W.D.J.Koch at a global level and Helianthemum caput-felis Boiss. at a regional level
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