344 research outputs found
A Review of Current and Historical Research Contributions to the Development of Ground Autonomous Vehicles for Agriculture
In this study, a comprehensive overview of the available autonomous ground platforms developed by universities and research groups that were specifically designed to handle agricultural tasks was performed. As cost reduction and safety improvements are two of the most critical aspects for farmers, the development of autonomous vehicles can be of major interest, especially for those applications that are lacking in terms of mechanization improvements. This review aimed to provide a literature evaluation of present and historical research contributions toward designing and prototyping agricultural ground unmanned vehicles. The review was motivated by the intent to disseminate to the scientific community the main features of the autonomous tractor named BOPS-1960, which was conceived in the 1960s at the Alma Mater Studiorum University of Bologna (UNIBO). Jointly, the main characteristics of the modern DEDALO unmanned ground vehicle (UGV) for orchard and vineyard operations that was designed recently were evaluated. The basic principles, technology and sensors used in the two UNIBO prototypes are described in detail, together with an analysis of UGVs for agriculture conceived in recent years by research centers all around the world
Energy absorption in actual tractor rollovers with different tire configurations
In order to better understand the complexities of modern tractor rollover, this paper investigates the energy absorbed by a Roll-Over Protective Structure (ROPS) cab during controlled lateral rollover testing carried out on a modern narrow-track tractor with a silent-block suspended ROPS cab. To investigate how different tractor set-ups may influence ROPS and energy partitioning, tests were conducted with two different wheel configurations, wide (equivalent to normal ‘open field’ operation) and narrow (equivalent to ‘orchard/vineyard’ operation), and refer to both the width of the tires and the corresponding track. Dynamic load cells and displacement transducers located at the ROPS-ground impact points provided a direct measurement of the energy absorbed by the ROPS cab frame. A trilateration method was developed and mounted onboard to measure load cell trajectory with respect to the cab floor in real-time. The associated video record of each rollover event provided further information and opportunity to explain the acquired data. The narrow tire configuration consistently subjected the ROPS cab frame to more energy than the wide tire arrangement. To better evaluate the influence of the ROPS cab silent-blocks in lateral rollover, static and dynamic tests were performed. The results confirm that tires influence the energy partition significantly and that further understanding of silent-blocks’ dynamic performance is warranted
First Blood & Marrow Transplant (BMT) Program in Nepal: a high cost procedure in a low economy country made available in a public hospital
Protein sizing with Differential Dynamic Microscopy
Introduced more than fifty years ago, dynamic light scattering is routinely
used to determine the size distribution of colloidal suspensions, as well as of
macromolecules in solution, such as proteins, nucleic acids, and their
complexes. More recently, differential dynamic microscopy has been proposed as
a way to perform dynamic light scattering experiments with a microscope, with
much less stringent constraints in terms of cleanliness of the optical
surfaces, but a potentially lower sensitivity due to the use of camera-based
detectors. In this work, we push bright-field differential dynamic microscopy
beyond known limits and show it to be sufficiently sensitive to size small
macromolecules in diluted solutions. By considering solutions of three
different proteins (Bovine Serum Albumin, Lysozyme, and Pepsin), we accurately
determine the diffusion coefficient and hydrodynamic radius of both single
proteins and small protein aggregates down to concentrations of a few
milligrams per milliliter. In addition, we present preliminary results showing
unexplored potential for the determination of virial coefficients. Our results
are in excellent agreement with the ones obtained in parallel with a
state-of-the-art commercial dynamic light scattering setup, showing that
differential dynamic microscopy represents a valuable alternative for rapid,
label-free protein sizing with an optical microscope
Segnalazione di un nuovo ittiosauro dal Cretaceo dell’Appennino modenese (Pavullo nel Frignano)
Alcuni frammenti vertebrali di ittiosauro sono stati recentemente rinvenuti in un calanco presso Pa- vullo nel Frignano (MO). I fossili sono stati trovati entro la Formazione delle Argille Varicolori di Cassio, datate al Cenomaniano superiore-Campaniano (Cretaceo). Tra i reperti rinvenuti è impor- tante segnalare un tratto di colonna vertebrale ancora parzialmente articolata. Si tratta del primo ritrovamento di questo tipo in Italia per quanto riguarda gli ittiosauri del Cretaceo. Alcuni dei corpi vertebrali in oggetto sono di dimensioni relativamente grandi, paragonabili a quelle già note per alcune specie di Platypterygiinae quali Platypterygius australis e P. americanus.Some vertebral fragments of ichthyosaur have recently been found in a clay badland near Pavullo nel Frignano (Modena Province). The finds were discovered in the “Argille Varicolori di Cassio” Formation, which dates from the upper Cenomanian-Campanian (Cretaceous). Among the fossils recovered, a portion of vertebral column, still partially articulated, is of outstanding importance. This is the first discovery of an articulated portion of a skeleton of a Cretaceous ichthyosaur in Italy. Some of the centra are relatively large, comparable to those already known for some species of Platypterygiinae such as Platypterygius australis and P. americanus
Effects of serum proteins on corrosion behavior of ISO 5832–9 alloy modified by titania coatings
Stainless steel ISO 5832–9 type is often used to
perform implants which operate in protein-containing physiological
environments. The interaction between proteins and
surface of the implant may affect its corrosive properties. The
aim of this work was to study the effect of selected serum
proteins (albumin and γ-globulins) on the corrosion of ISO
5832–9 alloy (trade name M30NW) which surface was modified
by titania coatings. These coatings were obtained by sol–
gel method and heated at temperatures of 400 and 800 °C. To
evaluate the effect of the proteins, the corrosion tests were
performed with and without the addition of proteins with
concentration of 1 g L−1 to the physiological saline solution
(0.9 % NaCl, pH 7.4) at 37 °C. The tests were carried out
within 7 days. The following electrochemical methods were
used: open circuit potential, linear polarization resistance, and
electrochemical impedance spectroscopy. In addition, surface
analysis by optical microscopy and X-ray photoelectron spectroscopy
(XPS) method was done at the end of weekly corrosion
tests. The results of corrosion tests showed that M30NW
alloy both uncoated and modified with titania coatings exhibits
a very good corrosion resistance during weekly exposition
to corrosion medium. The best corrosion resistance in
0.9 % NaCl solution is shown by alloy samples modified by
titania coating annealed at 400 °C. The serumproteins have no
significant effect onto corrosion of investigated biomedical
steel. The XPS results confirmed the presence of proteins on
the alloy surface after 7 days of immersion in proteincontaining
solutions.The investigations were supported by the National Science Centre project No. N N507 501339. The authors gratefully acknowledge Dr. Janusz
Sobczak and Dr. hab. Wojciech Lisowski from Institute of Physical
Chemistry of PAS for XPS surface analyses
118: Elevated CD14+ Cell Dose in Marrow Graft Correlates with Increased Mortality after Allogeneic Transplantation
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The nasal delivery of nanoencapsulated statins – An approach for brain delivery
© 2016 Clementino et al. Purpose: Along with their cholesterol-lowering effect, statins have shown a wide range of pleiotropic effects potentially beneficial to neurodegenerative diseases. However, such effects are extremely elusive via the conventional oral administration. The purpose of the present study was to prepare and characterize the physicochemical properties and the in vivo biodistribution of simvastatin-loaded lecithin/chitosan nanoparticles (SVT-LCNs) suitable for nasal administration in view of an improved delivery of the statins to the brain. Materials and methods: Chitosan, lecithin, and different oil excipients were used to prepare nanocapsules loaded with simvastatin. Particle size distribution, surface charge, structure, simvastatin loading and release, and interaction with mucus of nanoparticles were determined. The nanoparticle nasal toxicity was evaluated in vitro using RPMI 2651 nasal cell lines. Finally, in vivo biodistribution was assessed by gamma scintigraphy via Tc99m labeling of the particles. Results: Among the different types of nanoparticles produced, the SVT-LCN_MaiLab showed the most ideal physicochemical characteristics, with small diameter (200 nm), positive surface charge (+48 mV) and high encapsulation efficiency (EE; 98%). Size distribution was further confirmed by nanoparticle tracking analysis and electron microscopy. The particles showed a relatively fast release of simvastatin in vitro (35.6%±4.2% in 6 hours) in simulated nasal fluid. Blank nanoparticles did not show cytotoxicity, evidencing that the formulation is safe for nasal administration, while cytotoxicity of simvastatin-loaded nanoparticles (IC50) was found to be three times lower than the drug solution (9.92 vs 3.50 μM). In rats, a significantly higher radioactivity was evidenced in the brain after nasal delivery of simvastatin-loaded nanoparticles in comparison to the administration of a similar dose of simvastatin suspension. Conclusion: The SVT-LCNs developed presented some of the most desirable characteristics for mucosal delivery, that is, small particle size, positive surface charge, long-term stability, high EE, and mucoadhesion. In addition, they displayed two exciting features: First was their biodegradability by enzymes present in the mucus layer, such as lysozyme. This indicates a new Trojan-horse strategy which may enhance drug release in the proximity of the nasal mucosa. Second was their ability to enhance the nose-to-brain transport as evidenced by preliminary gamma scintigraphy studies
392: Delayed Recovery of Myeloid (mDC) and Plasmacytoid (pDC) Dendritic Cells at 3 Months after Allogeneic HSC Transplantation Correlates with an Increased Transplant-related and Overall Mortality Independently of GVHD
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