1,404 research outputs found
Investigation of carbon sequestration processes of reconstructed grasslands and wetlands to aid ecosystem service-based decision making
In this paper, we analysed the effect of habitat reconstructions on some parameters characterizing the carbon exchange processes of ecosystems. Besides extending our knowledge on the ecophysiological functioning of different plant communities, our work was motivated by international policy goals as well: a considerable amount of degraded ecosystems and their services was declared in the European Union to be reconstructed in the next few years. These kinds of projects need detailed impact analyses and a methodological grounding. We would like to contribute to these goals with the results of field measurements carried out in an extensive habitat reconstruction area in the Egyek-Pusztakócs habitat complex (Hortobágy National Park, Eastern Hungary). In this paper, we analysed the results of carbon and nitrogen contents of soils and biomass samples and the average net ecosystem exchange values of the investigated ecosystem types. Our results show that natural or near-natural, well-structured grasslands have an outstanding carbon sequestration and storing potential in the studied landscape type, the restored grasslands lag behind in every parameters. In the process of secondary succession, the carbon exchange characteristics of the restored grasslands seem to follow mainly the species composition, and the effects of land management can modify the effects of regeneration from the point of view of ecophysiological functioning
Reliability-as-a-Service for bearing risk assessment investigated with advanced mathematical models
As a key player in bearing service life, the lubricant chemistry has a profound effect on bearing reliability. To increase the reliability of bearings, an Industrial Analytics solution is proposed for proactive condition monitoring and this is delivered via a Reliability-as-a-Service application. The performance predictions of bearings rely on customized algorithms with the main focus on digitalizing lubricant chemistry; the principles behind these processes are outlined in this study. Subsequently, independent testing is performed to confirm the ability of the presented Industrial Analytics solution for such predictions. By deciphering the chemical compounds of lubricants and characteristics of the interface, the Industrial Analytics solution delivers a precise bearing reliability assessment a priori to predict service life of the operation. Bearing tests have shown that the classification system of this Industrial Analytics solution is able to predict 12 out of 13 bearing failures (92%). The described approach provides a proactive bearing risk classification that allows the operator to take immediate action in reducing the failure potential during smooth operation - preventing any potential damage from occurring. For this purpose, a mathematical model is introduced that derives a set of classification rules for oil lubricants, based on linear binary classifiers (support vector machines) that are applied to the chemical compound's mixture data.</p
Defect flows in minimal models
In this paper we study a simple example of a two-parameter space of
renormalisation group flows of defects in Virasoro minimal models. We use a
combination of exact results, perturbation theory and the truncated conformal
space approach to search for fixed points and investigate their nature. For the
Ising model, we confirm the recent results of Fendley et al. In the case of
central charge close to one, we find six fixed points, five of which we can
identify in terms of known defects and one of which we conjecture is a new
non-trivial conformal defect. We also include several new results on exact
properties of perturbed defects and on the renormalisation group in the
truncated conformal space approach.Comment: 35 pages, 21 figures. 1 reference adde
Effect of storage on physical and functional properties of extracellular vesicles derived from neutrophilic granulocytes.
AIM: To carry out a systematic study on the effect of different storage conditions on the number as well as the physical and functional properties of antibacterial extracellular vesicles (EVs) derived from human neutrophilic granulocytes. METHODS: Production of EVs with antibacterial properties was initiated by opsonized Zymosan A particles. The number of released fluorescent EVs was determined by flow cytometry following careful calibration. Physical properties and size of EVs were investigated by flow cytometry, dynamic light scattering and electron microscopy. Functional properties of EVs were tested by bacterial survival assay. RESULTS: Storage at +20 degrees C or +4 degrees C resulted in a significant decrease of EV number and antibacterial effect after 1 day. Storage at -20 degrees C did not influence the EV number up to 28 days, but induced a shift in EV size and almost complete loss of antibacterial function by 28 days. Storage at -80 degrees C had no significant effect either on EV number or size and allowed partial preservation of the antibacterial function up to 28 days. Snap-freezing did not improve the results, whereas the widely used cryoprotectants induced EV lysis. CONCLUSION: Storage significantly alters both the physical and functional properties of EVs even if the number of EVs stays constant. If storage is needed, EVs should be kept at -80 degrees C, preferably not longer than 7 days. For functional tests, freshly prepared EVs are recommended
A forged ‘chimera’ including the second specimen of the protostegid sea turtle Santanachelys gaffneyi and shell parts of the pleurodire Araripemys from the Lower Cretaceous Santana Group of Brazil
Fossils of Cretaceous sea turtles adapted to an open marine lifestyle remain rare finds to date. Furthermore, the relationships between extant sea turtles, chelonioids, and other Mesozoic marine turtles are still contested, with one key species being Santanachelysgaffneyi Hirayama, 1998, long considered the earliest true sea turtle. The species is an Early Cretaceous member of Protostegidae, a controversial clade either placed within or closely related to Chelonioidea or, alternatively, along the stem lineage of hidden-neck turtles (Cryptodira) and representing an independent open marine radiation. Santanachelysgaffneyi is one of the most completely preserved early protostegids and is therefore critical for establishing the global phylogenetic position of the group. However, the single known specimen of this taxon is yet to be described in detail. Here we describe a second specimen of Santanachelysgaffneyi from its type horizon, the Romualdo Formation (late Aptian) of the Santana Group of the Araripe basin, NE Brazil. The skeletal elements preserved include the posterior part of the skull, neck vertebrae, shoulder girdle, anterior-most and left/central part of the carapace with few peripherals, and plastron lacking most of the hyoplastra. The remaining part of the carapace was apparently completed by fossil dealers using an anterior part of the pleurodiran Araripemydidae, tentatively identified as a shell portion of cf. Araripemysbarretoi, a more common Santana fossil turtle, among other indeterminate turtle shell fragments. The purpose of this paper is to report the repatriation of the specimen to Brazil and to provide a preliminary description
Ex vivo infection of human embryonic spinal cord neurons prior to transplantation into adult mouse cord
<p>Abstract</p> <p>Background</p> <p>Genetically modified pseudorabies virus (Prv) proved suitable for the delivery of foreign genes to rodent embryonic neurons <it>ex vivo </it>and maintaining foreign gene expression after transplantation into spinal cord in our earlier study. The question arose of whether human embryonic neurons, which are known to be more resistant to Prv, could also be infected with a mutant Prv. Specifically, we investigated whether a mutant Prv with deleted ribonucleotide reductase and early protein 0 genes has the potential to deliver marker genes (gfp and β-gal) into human embryonic spinal cord neurons and whether the infected neurons maintain expression after transplantation into adult mouse cord.</p> <p>Results</p> <p>The results revealed that the mutant Prv effectively infected human embryonic spinal cord neurons <it>ex vivo </it>and the grafted cells exhibited reporter gene expression for several weeks. Grafting of infected human embryonic cells into the spinal cord of immunodeficient (rnu-/rnu-) mice resulted in the infection of some of the host neurons.</p> <p>Discussion</p> <p>These results suggest that Prv is suitable for the delivery of foreign genes into transplantable human cells. This delivery method may offer a new approach to use genetically modified cells for grafting in animal models where spinal cord neuronal loss or axon degeneration occurs.</p
Cellular architecture and transmitter phenotypes of neurons of the mouse median raphe region
The median raphe region (MRR, which consist of MR and paramedian raphe regions) plays a crucial role in regulating cortical as well as subcortical network activity and behavior, while its malfunctioning may lead to disorders, such as schizophrenia, major depression, or anxiety. Mouse MRR neurons are classically identified on the basis of their serotonin (5-HT), vesicular glutamate transporter type 3 (VGLUT3), and gamma-aminobutyric acid (GABA) contents; however, the exact cellular composition of MRR regarding transmitter phenotypes is still unknown. Using an unbiased stereological method, we found that in the MR, 8.5 % of the neurons were 5-HT, 26 % were VGLUT3, and 12.8 % were 5-HT and VGLUT3 positive; whereas 37.2 % of the neurons were GABAergic, and 14.4 % were triple negative. In the whole MRR, 2.1 % of the neurons were 5-HT, 7 % were VGLUT3, and 3.6 % were 5-HT and VGLUT3 positive; whereas 61 % of the neurons were GABAergic. Surprisingly, 25.4 % of the neurons were triple negative and were only positive for the neuronal marker NeuN. PET-1/ePET-Cre transgenic mouse lines are widely used to specifically manipulate only 5-HT containing neurons. Interestingly, however, using the ePET-Cre transgenic mice, we found that far more VGLUT3 positive cells expressed ePET than 5-HT positive cells, and about 38 % of the ePET cells contained only VGLUT3, while more than 30 % of 5-HT cells were ePET negative. These data should facilitate the reinterpretation of PET-1/ePET related data in the literature and the identification of the functional role of a putatively new type of triple-negative neuron in the MRR
Structural and functional properties of a plant NRAMP-related aluminum transporter
The transport of transition metal ions by members of the SLC11/NRAMP family constitutes a ubiquitous mechanism for the uptake of Fe and Mn across all kingdoms of life. Despite the strong conservation of the family, two of its branches have evolved a distinct substrate preference with one mediating Mg uptake in prokaryotes and another the transport of Al into plant cells. Our previous work on the SLC11 transporter from Eggerthella lenta revealed the basis for its Mg selectivity (Ramanadane et al., 2022). Here, we have addressed the structural and functional properties of a putative Al transporter from Setaria italica. We show that the protein transports diverse divalent metal ions and binds the trivalent ions Al and Ga, which are both presumable substrates. Its cryo-electron microscopy (cryo-EM) structure displays an occluded conformation that is closer to an inward- than an outward-facing state, with a binding site that is remodeled to accommodate the increased charge density of its transported substrate
Early Prediction of Movie Box Office Success based on Wikipedia Activity Big Data
Use of socially generated "big data" to access information about collective
states of the minds in human societies has become a new paradigm in the
emerging field of computational social science. A natural application of this
would be the prediction of the society's reaction to a new product in the sense
of popularity and adoption rate. However, bridging the gap between "real time
monitoring" and "early predicting" remains a big challenge. Here we report on
an endeavor to build a minimalistic predictive model for the financial success
of movies based on collective activity data of online users. We show that the
popularity of a movie can be predicted much before its release by measuring and
analyzing the activity level of editors and viewers of the corresponding entry
to the movie in Wikipedia, the well-known online encyclopedia.Comment: 13 pages, Including Supporting Information, 7 Figures, Download the
dataset from: http://wwm.phy.bme.hu/SupplementaryDataS1.zi
Pre-Excitation Studies for Rubidium-Plasma Generation
The key element in the Proton-Driven-Plasma-Wake-Field-Accelerator (AWAKE)
project is the generation of highly uniform plasma from Rubidium vapor. The
standard way to achieve full ionization is to use high power laser which can
assure the over-barrier-ionization (OBI) along the 10 meters long active
region. The Wigner-team in Budapest is investigating an alternative way of
uniform plasma generation. The proposed Resonance Enhanced Multi Photon
Ionization (REMPI) scheme probably can be realized by much less laser power. In
the following the resonant pre-excitations of the Rb atoms are investigated,
theoretically and the status report about the preparatory work on the
experiment are presented.Comment: 8 pages, 6 figures, submitted to Nucl. Inst. and Meth. in Phys. Res.
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