130 research outputs found
Multilobular tumour of the caudal cranium causing severe cerebral and cerebellar compression in a dog
Multilobular tumour of bone (MTB) is an uncommon tumour and is usually located in the skull. A 13-year-old mixed breed dog was presented with a two-week history of progressively worsening vestibular dysfunction and cognitive abnormalities; it appeared demented and showed asymmetric ataxia and hypermetria of all limbs. The owner opted to have the animal euthanised. Necropsy revealed a large mass occupying the right occipital, parietal and temporal bones, severely compressing the cerebellum and the right occipital lobe. Histologically, it was characterised by the presence of multiple lobules containing osteoid or cartilage and separated by fibrous septae, features typical of MTB. Lung metastases were evident. To our knowledge, this is the first report of an MTB causing both severe cerebral and cerebellar compression and the second detailed report of an MTB of the occipital bone. MTB should be included in the differential diagnosis of bone tumours as well as in cases with central vestibular disease
Direct Visualization of the Reversible O2â/Oâ Redox Process in LiâRich Cathode Materials
Conventional cathodes of Liâion batteries mainly operate through an insertionâextraction process involving transition metal redox. These cathodes will not be able to meet the increasing requirements until lithiumârich layered oxides emerge with beyondâcapacity performance. Nevertheless, inâdepth understanding of the evolution of crystal and excess capacity delivered by Liârich layered oxides is insufficient. Herein, various in situ technologies such as Xâray diffraction and Raman spectroscopy are employed for a typical material Li1.2Ni0.2Mn0.6O2, directly visualizing OâOâ (peroxo oxygen dimers) bonding mostly along the câaxis and demonstrating the reversible O2â/Oâ redox process. Additionally, the formation of the peroxo OO bond is calculated via density functional theory, and the corresponding OO bond length of â1.3 Ă
matches well with the in situ Raman results. These findings enrich the oxygen chemistry in layered oxides and open opportunities to design highâperformance positive electrodes for lithiumâion batteries.A typical Liârich material Li1.2Ni0.2Mn0.6O2 is systematically analyzed by in situ Xâray diffraction and Raman spectroscopy. Peroxo OO bonding is directly visualized mostly along the câaxis and a reversible O2â/Oâ redox process is demonstrated. Additionally, the formation of peroxo OO bonds is calculated via density functional theory, and the corresponding OO bond length of â1.3 Ă
matches well with the in situ Raman results.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143642/1/adma201705197.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143642/2/adma201705197-sup-0001-S1.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143642/3/adma201705197_am.pd
Solvent-selective routing for centrifugally automated solid-phase purification of RNA
The final publication is available at Springer via https://doi.org/10.1007/s10404-014-1477-9.We present a disc-based module for rotationally controlled solid-phase purification of RNA from cell lysate. To this end, multi-stage routing of a sequence of aqueous and organic liquids into designated waste and elution reservoirs is implemented by a network of strategically placed, solvent-selective composite valves. Using a bead-based stationary phase at the entrance of the router, we show that total RNA is purified with high integrity from cultured MCF7 and T47D cell lines, human leucocytes and Haemophilus influenzae cell lysates. Furthermore, we demonstrate the broad applicability of the device through the in vitro amplification of RNA purified on-disc using RT-PCR and NASBA. Our novel router will be at the pivot of a forthcoming, fully integrated and automated sample preparation system for RNA-based analysis.Peer reviewe
Cation insertion to break the activity/stability relationship for highly active oxygen evolution reaction catalyst
The production of hydrogen at a large scale by the environmentally-friendly electrolysis process is currently hampered by the slow kinetics of the oxygen evolution reaction (OER). We report a solid electrocatalyst α-Li2IrO3 which upon oxidation/delithiation chemically reacts with water to form a hydrated birnessite phase, the OER activity of which is five times greater than its non-reacted counterpart. This reaction enlists a bulk redox process during which hydrated potassium ions from the alkaline electrolyte are inserted into the structure while water is oxidized and oxygen evolved. This singular charge balance process for which the electrocatalyst is solid but the reaction is homogeneous in nature allows stabilizing the surface of the catalyst while ensuring stable OER performances, thus breaking the activity/stability tradeoff normally encountered for OER catalysts
Strategies for Maintaining the CoachâAnalyst Relationship Within Professional Football Utilizing the COMPASS Model: The Performance Analystâs Perspective
There is a considerable body of research by that has investigated the coachâ athlete relationship in sport. However, given the multi-disciplinary nature of modern elite coaching, there is a scarcity of research focusing on the relationship between coaches and other members of the coaching and support team. This study examined the perceptions of six elite professional football analystâs relationships with their respective coaches. Semi structured interviews utilizing the COMPASS Framework were conducted focusing on Conflict, Openness, Motivation, Preventative Strategies, Assurance, Support, and Social Networks. The results verified that the COMPASS Model of relationship maintenance was applicable to this dyad. Content analysis indicated that there was 215 raw data units comprising of 16 higher order themes across the model which was further broken down into 29 lower order themes. All aspects of the model were found to contribute toward a positively maintained relationship. Having an open relationship underpinned by honesty and being able to provide an opinion was seen as the highest rated attribute that was closely followed by supporting the coach by understanding their requirements for successful coaching practice. Not meeting the coachâs expectations was found to cause conflict and was further highlighted by an inductive analysis that revealed the existence of a relationship that is fundamentally dictated by the coach. Implications of this investigation are that professionals which support elite performers need to set out clear expectations of working practice and hierarchies in order to minimize the chance of internal conflict that can impact on the service levels received by the performer
Oxygen redox chemistry without excess alkali-metal ions in Na[MgMn]O
The search for improved energy-storage materials has revealed Li- and Na-rich intercalation compounds as promising high-capacity cathodes. They exhibit capacities in excess of what would be expected from alkali-ion removal/reinsertion and charge compensation by transition-metal (TM) ions. The additional capacity is provided through charge compensation by oxygen redox chemistry and some oxygen loss. It has been reported previously that oxygen redox occurs in O 2 orbitals that interact with alkali ions in the TM and alkali-ion layers (that is, oxygen redox occurs in compounds containing LiâO(2)âLi interactions). Na[MgMn]O exhibits an excess capacity and here we show that this is caused by oxygen redox, even though Mg resides in the TM layers rather than alkali-metal (AM) ions, which demonstrates that excess AM ions are not required to activate oxygen redox. We also show that, unlike the alkali-rich compounds, Na[MgMn]O does not lose oxygen. The extraction of alkali ions from the alkali and TM layers in the alkali-rich compounds results in severely underbonded oxygen, which promotes oxygen loss, whereas Mg remains in Na[MgMn]O, which stabilizes oxygen
Protein hydrolysates from animal processing by-products as a source of bioactive molecules with interest in animal feeding: A review
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