2,427 research outputs found
DIFFERENZIAMENTO E CREAZIONE DI UN MICROAMBIENTE RIGENERATIVO NELLA LESIONE MIDOLLARE DA PARTE DEI PRECURSORI NEURALI POST MORTEM (PM-NPCS). ANALISI DI TIPO BIOCHIMICO, MORFOLOGICO, ED IN VIVO ATTRAVERSO LA RISONANZA MAGENTICA ED IL RECUPERO FUNZIONALE DEGLI ARTI POSTERIORI
Traumatic injuries in central nervous system lead to severe and permanent neurological deficit. Particularly, traumatic spinal cord injury often results in a devastating loss of neurological function below the injury site. Since the loss of CNS neurons may not be replaced by the proliferation of the surviving ones, intraspinal transplantation of exogenous neuronal cells or tissue has been accepted for a long time as a way to obtain a partial reconstruction of the lost cord tissue and to promote recovery of neurological function.
Cell-based therapies in the injured spinal cord are intended to fill lesion cavities, which typically develop at an injury site, and to provide a cellular growth-conducive substrate for re-growing axons. Various cell types such as fibroblasts, olfactory ensheathing cells, Schwann cells and neural stem \u2044precursor cells have been used to regenerate or replace injured spinal cord parenchyma, and to elicit axonal regen- eration which is the primary goal of regenerative medicine and one of the prime motivations for the study of stem cells (NCSs).
Unfortunately when NSCs are administrated in a spinal cord injury model they modulate the inflammatory response but do not differentiate into mature cells and are quickly engulfed by macrophages present at lesion site. Recently we isolated a new class of neural stem cell from the subventricular zone of mice forebrain named Post-Mortem Neural Precursor Cells (PM-NPCs), that are capable of surviving after a prolonged ischemic insult. PM-NPCs for their potentiality in terms of proliferation and differentiation capabilities, are a good tool for tissue replacement therapies. In this study we focused on transplantation of PM-NPCs in a murine model of spinal cord injury by endovenous injection within 2 hours after injury. After administration, cells migrate specifically to the site of injury, as demonstrated both by ex-vivo immunoistochemistry and in-vivo MRI after PM-NPCs labelling with Superparamagnetic Iron Oxide Particles (SPIOs). Interestingly, these cells survive in such an unfavorable enviroment wich is the injury site and differentiate predominantly into cholinergic neurons, reconstituting a rich axonal and dendritic network and promoting a marked axonal regeneration across the injury site of monoaminergic fibers within 30 days from their administration.
Fluororuby injection in the dorsal funiculi rostral to the lesion site shows
that some spared and/or regenereting corticospinal (CS) labelled fibres bypass the lesion site and are in the caudal portion of PM-NSCs mice treated spinal cord, where few or none CS labelled fibers are found in saline trated mice. Moreover, beavhioral assesment evaluated by means of Basso Mouse Scale (BMS), shows a significantly improve of hind limb function in PM-NPCs treated mice compared with animals treated with placebo.
Eventually, the molecular analysis of the lesion site shows that PM-NPCs induce a remodulation of inflammatory response through the reduction of astrocytes activation and glial scar formation, and the reduction of immunitary cells infiltration (neutrophils and macrophages) leading to a better tissue preservation.
Moreover, the expression of proinflammatory cytokines and release of neurotrophic factors are reguated by PM-NPCs treatement: some proinflammatory cytokines (IL-6, MIP-2 and TNF alpha) levels significantly decrease after 48 hours from spinal cord injury and PM-NPCs transplantation, while after 7 days we observe an increase of IL-6 and TNF alpha probably because at longer time those cytokines are necessary to support the regenerative process according to the literature. These data suggest that PM-NPCs may represent a good source for cellular therapy in neurodegenerative disorders, specially on spinal cord injury
Intermolecular interactions of substituted benzenes on multi-walled carbon nanotubes grafted on HPLC silica microspheres and interaction study through artificial neural networks
Purified multi-walled carbon nanotubes (MWCNTs) grafted onto silica microspheres by gamma-radiation were applied as a HPLC stationary phase for investigating the intermolecular interactions between MWCNTs and substituted benzenes. The synthetic route, simple and not requiring CNTs derivatization, involved no alteration of the nanotube original morphology and physical–chemical properties. The affinity of a set of substituted benzenes for the MWCNTs was studied by correlating the capacity factor (k′) of each probe to its physico-chemical characteristics (calculated by Density Functional Theory). The correlation was found through a theoretical approach based on feedforward neural networks. This strategy was adopted because today these calculations are easily affordable for small molecules (like the analytes), and many critical parameters needed are not known. This might increase the applicability of the proposed method to other cases of study. Moreover, it was seen that the normal linear fit does not provide a good model. The interaction on the MWCNT phase was compared to that of an octadecyl (C18) reversed phase, under the same elution conditions. Results from trained neural networks indicated that the main role in the interactions between the analytes and the stationary phases is due to dipole moment, polarizability and LUMO energy. As expected for the C18 stationary phase correlation, is due to dipole moment and polarizability, while for the MWCNT stationary phase primarily to LUMO energy followed by polarizability, evidence for a specific interaction between MWCNTs and analytes. The CNT-based hybrid material proved to be not only a chromatographic phase but also a useful tool to investigate the MWCNT-molecular interactions with variously substituted benzenes
Misura tridimensionale dei tempi di rilassamento longitudinali (spin - reticolo) di un dosimetro Fricke mediante una apparecchiatura di diagnostica RMN da 1.5 T
Stability of wide-graded rubble mounds
The Delft University of Technology provided the laboratory facilities to carry out physical model tests on a wide graded rubble mound structure representative of the core of a breakwater. The parameter D85/D15, describing the stone-size gradation of the construction material, was varied between the values 2.71 and 17.7, and two different seaward slopes of the model structure were also tested. The reshaped cross-shore profiles measured during the tests showed how if the grading increases the stability of the structure is reduced.
In conclusion, this research points out how the formulas provided by the technical literature are not reliable in representing the effects of a very wide stone-size gradation in the stability of a rubble mound structure. Physical model tests proved to be a suited way to investigate these effects, as the nature of the phenomena who play a role in the stability does not allow a simple analytical representation. The tests carried out within the present study lead to the implementation of a numerical model of practical use for engineers and contractors: further investigations through laboratory tests are recommended to validate and extend the findings of this study. Another proposed direction for further research is the comparison between the results of physical model tests and the output of numerical models
Cathode Active Material Recycling from Spent Lithium Batteries: A Green (Circular) Approach Based on Deep Eutectic Solvents
The transition to a circular economy vision must handle the increasing request of metals required to satisfy the battery industry; this can be obtained by recycling and feeding back secondary raw materials recovered through proper waste management. Here, a novel and green proof-of-concept was developed, based on deep eutectic solvents (DESs) to fully and easily recover valuable metals from various cathode active materials, including LiMn2O4, LiNi0.5Mn1.5O4, and LiNi0.8Co0.2O2. DES composed of choline chloride and lactic acid could leach Li, Mn, Co, and Ni, achieving efficiency of 100 % under much milder conditions with respect to the previous literature. For the first time, to our best knowledge, a two-step approach was reported in the case of LiNi0.8Co0.2O2 for selective recovery of Li, Co, and Ni with high yield and purity. Furthermore, other cathode components, namely aluminum current collector and binder, were found to be not dissolved by the proposed DES, thus making a simple separation from the active material possible. Finally, this strategy was designed to easily regenerate and reuse the leaching solvents for more than one extraction, thus further boosting process sustainability
Electromagnetic dipole moments of charged baryons with bent crystals at the LHC
We propose a unique program of measurements of electric and magnetic dipole
moments of charm, beauty and strange charged baryons at the LHC, based on the
phenomenon of spin precession of channeled particles in bent crystals. Studies
of crystal channeling and spin precession of positively- and negatively-charged
particles are presented, along with feasibility studies and expected
sensitivities for the proposed experiment using a layout based on the LHCb
detector.Comment: 19 pages, 13 figure
How good are we at determining risk? Quantifying the accuracy of clinician determined risk for VTE prophylaxis
Objectives:
Create and validate a simple tool for concurrent audits of risk stratification, compliance and documentation
Evaluate accuracy of clinician risk stratification and prophylatic ordering practice compared with a standardized Caprini RAM across different assigned risk categories
Provide recommendations for EPIC VTE Prophylaxis CDS Developmenthttps://jdc.jefferson.edu/patientsafetyposters/1050/thumbnail.jp
Efficient Passive ICS Device Discovery and Identification by MAC Address Correlation
Owing to a growing number of attacks, the assessment of Industrial Control
Systems (ICSs) has gained in importance. An integral part of an assessment is
the creation of a detailed inventory of all connected devices, enabling
vulnerability evaluations. For this purpose, scans of networks are crucial.
Active scanning, which generates irregular traffic, is a method to get an
overview of connected and active devices. Since such additional traffic may
lead to an unexpected behavior of devices, active scanning methods should be
avoided in critical infrastructure networks. In such cases, passive network
monitoring offers an alternative, which is often used in conjunction with
complex deep-packet inspection techniques. There are very few publications on
lightweight passive scanning methodologies for industrial networks. In this
paper, we propose a lightweight passive network monitoring technique using an
efficient Media Access Control (MAC) address-based identification of industrial
devices. Based on an incomplete set of known MAC address to device
associations, the presented method can guess correct device and vendor
information. Proving the feasibility of the method, an implementation is also
introduced and evaluated regarding its efficiency. The feasibility of
predicting a specific device/vendor combination is demonstrated by having
similar devices in the database. In our ICS testbed, we reached a host
discovery rate of 100% at an identification rate of more than 66%,
outperforming the results of existing tools.Comment: http://dx.doi.org/10.14236/ewic/ICS2018.
Quantifying Patient Reported and Documented Compliance with Adjuncts to Venous Thromboembolism Prophylaxis
Objectives:
1. Measure patient compliance with pharmacologic, mechanical and ambulatory prophylactic measures.
2. Evaluate for agreement between nursing documentation and patient reported compliance with mechanical and ambulatory prophylactic measures.https://jdc.jefferson.edu/patientsafetyposters/1042/thumbnail.jp
Coherent control with shaped femtosecond laser pulses applied to ultracold molecules
We report on coherent control of excitation processes of translationally
ultracold rubidium dimers in a magneto-optical trap by using shaped femtosecond
laser pulses. Evolution strategies are applied in a feedback loop in order to
optimize the photoexcitation of the Rb2 molecules, which subsequently undergo
ionization or fragmentation. A superior performance of the resulting pulses
compared to unshaped pulses of the same pulse energy is obtained by
distributing the energy among specific spectral components. The demonstration
of coherent control to ultracold ensembles opens a path to actively influence
fundamental photo-induced processes in molecular quantum gases
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