766 research outputs found
On the thermodynamics of first-order phase transition smeared by frozen disorder
The simplified model of first-order transition in a media with frozen
long-range transition-temperature disorder is considered. It exhibits the
smearing of the transition due to appearance of the intermediate inhomogeneous
phase with thermodynamics described by the ground state of the short-range
random-field Ising model. Thus the model correctly reproduce the persistence of
first-order transition only in dimensions d > 2, which is found in more
realistic models. It also allows to estimate the behavior of thermodynamic
parameters near the boundaries of the inhomogeneous phase.Comment: 4 page
Magnetic nanocomposites at microwave frequencies
Most conventional magnetic materials used in the electronic devices are
ferrites, which are composed of micrometer-size grains. But ferrites have small
saturation magnetization, therefore the performance at GHz frequencies is
rather poor. That is why functionalized nanocomposites comprising magnetic
nanoparticles (e.g. Fe, Co) with dimensions ranging from a few nm to 100 nm,
and embedded in dielectric matrices (e.g. silicon oxide, aluminium oxide) have
a significant potential for the electronics industry. When the size of the
nanoparticles is smaller than the critical size for multidomain formation,
these nanocomposites can be regarded as an ensemble of particles in
single-domain states and the losses (due for example to eddy currents) are
expected to be relatively small. Here we review the theory of magnetism in such
materials, and we present a novel measurement method used for the
characterization of the electromagnetic properties of composites with
nanomagnetic insertions. We also present a few experimental results obtained on
composites consisting of iron nanoparticles in a dielectric matrix.Comment: 20 pages, 10 figures, 5 table
Accurate DNA assembly and genome engineering with optimized uracil excision cloning
Simple
and reliable DNA editing by uracil excision (a.k.a. USER
cloning) has been described by several research groups, but the optimal
design of cohesive DNA ends for multigene assembly remains elusive.
Here, we use two model constructs based on expression of <i>gfp</i> and a four-gene pathway that produces β-carotene to optimize
assembly junctions and the uracil excision protocol. By combining
uracil excision cloning with a genomic integration technology, we
demonstrate that up to six DNA fragments can be assembled in a one-tube
reaction for direct genome integration with high accuracy, greatly
facilitating the advanced engineering of robust cell factories
The prognostic value of extramural venous invasion in preoperative MRI of rectal cancer patients
Aim This study aimed to examine the prognostic value of extramural venous invasion observed in preoperative MRI on survival and recurrences. Method In total, 778 rectal cancer patients were evaluated in multidisciplinary meetings in Helsinki University Hospital during the years 2016-2018. 635 patients met the inclusion criteria of stage I-III disease and were intended for curative treatment at the time of diagnosis. 128 had extramural venous invasion in preoperative MRI. Results The median follow-up time was 2.5 years. In a univariate analysis extramural venous invasion was associated with poorer disease-specific survival (hazard ratio [HR] 2.174, 95% CI 1.118-4.224, P = 0.022), whereas circumferential margin = T3c or nodal positivity were not. Disease recurrence occurred in 17.3% of the patients: 13.4% had metastatic recurrence only, 1.7% mere local recurrence and 2.2% both metastatic and local recurrence. In multivariate analysis, extramural venous invasion (HR 1.734, 95% CI 1.127-2.667, P = 0.012) and nodal positivity (HR 1.627, 95% CI 1.071-2.472, P = 0.023) were risk factors for poorer disease-free survival (DFS). Circumferential marginPeer reviewe
Antibodies to decorin-binding protein B (DbpB) in the diagnosis of Lyme neuroborreliosis in children
Peer reviewe
Glycodelin-A interacts with fucosyltransferase on human sperm plasma membrane to inhibit spermatozoa-zona pellucida binding
Fertilization depends on successful binding of the spermatozoa to the zona pellucida of the oocyte. Glycodelin-A inhibits spermatozoa-zona pellucida binding. Previous data showed that glycodelin-A receptor(s) and zona pellucida protein receptor(s) on human spermatozoa are closely related. Using a chemical cross-linking approach, the glycodelin-A-sperm receptor complex was isolated. The receptor was identified to be fucosyltransferase-5 (FUT5) by mass spectrometry and confirmed with the use of anti-FUT5 antibodies. Sperm FUT5 was an externally oriented integral membrane protein in the acrosomal region of human spermatozoa. Biologically active FUT5 was purified from spermatozoa. Co-immunoprecipitation confirmed the interaction between glycodelin-A and sperm FUT5. Solubilized zona pellucida reduced the binding of glycodelin-A to sperm FUT5. An anti-FUT5 antibody and FUT5 acceptor blocked the binding of glycodelin-A to spermatozoa and the zona binding inhibitory activity of glycodelin-A. Sperm FUT5 bound strongly to intact and solubilized human zona pellucida. The equilibrium dissociation constant of sperm FUT5 binding to solubilized zona pellucida was 42.82 pmol/ml. These observations suggest that human sperm FUT5 is a receptor of glycodelin-A and zona pellucida proteins, and that glycodelin-A inhibits spermatozoa-zona binding by blocking the binding of sperm FUT5 to the zona pellucida.published_or_final_versio
Influence of particle properties on convective heat transfer of nanofluids
Š 2017 An experimental study is performed in order to examine how particle properties such as size and thermal conductivity affect the convection heat transfer of nanofluids. For this purpose, we prepare and study self-synthesized water-based nanofluids with different kinds of particles: polystyrene, SiO 2 , Al 2 O 3 and micelles. Concentrations of the nanofluids vary in the range of 0.1â1.8 vol-% and particle sizes between 8 and 58 nm. Full-scale convective heat transfer experiments are carried out using an annular tube heat exchanger with the Reynolds numbers varying in the range of 1000â11000. The pressure losses are also taken into account in the analysis in order to assess the feasibility of the nanofluids for practical forced convection heat transfer applications. The fluids are thoroughly characterized: viscosities, thermal conductivities, densities, particle size distributions, shapes and zeta potentials are all determined experimentally. In many previous studies, anomalous enhancement in convective heat transfer is observed based on comparison of the Nusselt numbers with equal Reynolds numbers. Also in this work, the nanofluids exhibit Nusselt numbers higher than water when compared on this basis. However, this comparison neglects the impact of differences in the Prandtl numbers, and therefore the altered thermal properties of nanofluids are not properly taken into account. In this study, no difference in Nusselt numbers is observed when the Prandtl number is properly considered in the analysis. All nanofluids performed as the Gnielinski correlation predicts, and the widely reported anomalous convective heat transfer enhancement was not observed with any nanoparticle types. Instead, we show that the convection heat transfer behavior of nanofluids can be explained through the altered thermal properties alone. However, addition of any type of nanoparticles was observed to change the fluid properties in an unfavorable manner: the viscosity increases significantly, while only moderate enhancement in the thermal conductivity is obtained. The more viscous nanofluids reach lower Reynolds numbers than water with equal pumping powers resulting in lower heat transfer coefficients. However, the increase in viscosity, and therefore also the deterioration of the convective heat transfer, is less pronounced for the nanofluids with smaller particle size indicating that small particle size is preferable for convective heat transfer applications
Peptic Fluorescent "Signal-On" and "Signal-Off" Sensors Utilized for the Detection Protein Post-Translational Modifications
Protein post-translational modifications (PTMs) are typically enzyme-catalyzed events generating functional diversification of proteome; thus, multiple PTM enzymes have been validated as potential drug targets. We have previously introduced energy-transfer-based signal-modulation method called quenching resonance energy transfer (QRET), and utilize it to monitor PTM addition or removal using the developed peptide-break technology. Now we have reinvented the QRET technology, and as a model, we introduced the tunable fluorescent "signal-on" and "signal-off" detection scheme in the peptide-break PTM detection. Taking the advantage of time-resolved fluorescence-based single-label detection technology, we were able to select the signal direction upon PTM addition or removal by simply introducing different soluble Eu3+-signal-modulating molecule. This enables the selection of positive signal change upon measurable event, without any additional labeling steps, changes in assay condition or Eu3+-reporter. The concept functionality was demonstrated with four Eu3+-signal modulators in a high-throughput compatible kinase and phosphatase assays using signal-on and signal-off readout at 615 nm or time-resolved Forster resonance energy transfer at 665 nm. Our data suggest that the introduced signal modulation methodology provides a transitional fluorescence-based single-label detection concept not limited only to PTM detection
A report on the health and social care listening event
The purpose of the Listening Event was to enable a wide range of people, including professionals working in statutory, voluntary and other organisations and members of the public, to âhave a sayâ about health and social care and what we as a University can do for and with these partners and the public. We particularly wanted to hear about key concerns of the University such as:
⢠Strengthening community engagement and partnerships
⢠Health and social care training we should be providing, for whom, and how this is delivered
⢠Ideas relating to the University themes including media, use of space and buildings, human rights, social justice and security
⢠Research topics we should be addressing
However the main strength of the Listening Event approach is that topics for discussion are mostly led by participants who attend. On this occasion, the
discussion topics were very much focused on the concerns of participants and lots of information and ideas were generated. The task now is for the event planning team to review the discussion notes and identify what can be
addressed and how, in the short, medium and long term. This planning will be taking place over the Autumn in 2011, and any participants or readers of this report are more than welcome to get in touch to work with us or add their views.
The purpose of this report is to record all discussion summaries for sharing amongst participants and others. It is important that participants especially get to read what others had said at the event. The report will lead to changes in University practices such as the content of some of our courses and new business ideas and relationships will also be explored. The event itself provided a useful means of public engagement that others may wish to adopt
International Veterinary Epilepsy Task Force consensus report on epilepsy definition, classification and terminology in companion animals
Dogs with epilepsy are among the commonest neurological patients in veterinary practice and therefore have historically attracted much attention with regard to definitions, clinical approach and management. A number of classification proposals for canine epilepsy have been published during the years reflecting always in parts the current proposals coming from the human epilepsy organisation the International League Against Epilepsy (ILAE). It has however not been possible to gain agreed consensus, âa common languageâ, for the classification and terminology used between veterinary and human neurologists and neuroscientists, practitioners, neuropharmacologists and neuropathologists. This has led to an unfortunate situation where different veterinary publications and textbook chapters on epilepsy merely reflect individual author preferences with respect to terminology, which can be confusing to the readers and influence the definition and diagnosis of epilepsy in first line practice and research studies.
In this document the International Veterinary Epilepsy Task Force (IVETF) discusses current understanding of canine epilepsy and presents our 2015 proposal for terminology and classification of epilepsy and epileptic seizures. We propose a classification system which reflects new thoughts from the human ILAE but also roots in former well accepted terminology. We think that this classification system can be used by all stakeholders
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