1,417 research outputs found
High Fidelity Tape Transfer Printing Based On Chemically Induced Adhesive Strength Modulation
Transfer printing, a two-step process (i.e. picking up and printing) for heterogeneous integration, has been widely exploited for the fabrication of functional electronics system. To ensure a reliable process, strong adhesion for picking up and weak or no adhesion for printing are required. However, it is challenging to meet the requirements of switchable stamp adhesion. Here we introduce a simple, high fidelity process, namely tape transfer printing(TTP), enabled by chemically induced dramatic modulation in tape adhesive strength. We describe the working mechanism of the adhesion modulation that governs this process and demonstrate the method by high fidelity tape transfer printing several types of materials and devices, including Si pellets arrays, photodetector arrays, and electromyography (EMG) sensors, from their preparation substrates to various alien substrates. High fidelity tape transfer printing of components onto curvilinear surfaces is also illustrated
ESR mapping of polar-cap patches in the dark cusp
[1] We present the first ever measurement of the full thermal plasma properties, of an ionospheric patch in full darkness in the noon region where patches are believed to form. Further these data present the first experimental evidence for the Lockwood and Carlson class of mechanisms for forming patches by plasma injection. These data were possible only because of a new measurement capability we had to develop. We introduce the capability here because it crosses the high-speed threshold that now allows study of a broader class of mesoscale plasma flow-transients, which are thought to occur over time scales near 2 minutes vice 8-10 minutes. Cumulatively such transients may significantly drive global convection. We demonstrate both the validity of and need for our new measurement capability, by presenting a transient flow reversal sweeping across a 500 by 1000 km area, with initial reversal in 4 minutes, and recovery within 6 minutes
Serum prolactin as a biomarker for the study of intracerebral dopamine effect in adult patients with phenylketonuria: a cross-sectional monocentric study
BACKGROUND: It has been previously postulated that high phenylalanine (Phe) might disturb intracerebral dopamine production, which is the main regulator of prolactin secretion in the pituitary gland. Previously, various associations between Phe and hyperprolactinemia were revealed in studies performed in phenylketonuria (PKU) children and adolescents. The aim of the present study was to clarify whether any relation between serum phenylalanine and prolactin levels can be found in adult PKU patients. PATIENTS AND METHODS: We conducted a cross-sectional, monocentric study including 158 adult patients (male n = 68, female n = 90) with PKU. All patients were diagnosed during newborn screening and were treated since birth. Serum Phe, tyrosine (Tyr), prolactin (PRL), and thyroid-stimulating hormone (TSH) levels were measured, and Phe/Tyr ratio was calculated. Males and females were analyzed separately because the serum prolactin level is gender-dependent. RESULTS: No significant correlations were found between serum phenylalanine, tyrosine, or the Phe/Tyr ratio and serum prolactin level either in the male or in the female group. CONCLUSIONS: In treated adult PKU patients, the serum prolactin level may not be significantly influenced by Phe or Tyr serum levels
The extraordinary evolutionary history of the reticuloendotheliosis viruses
The reticuloendotheliosis viruses (REVs) comprise several closely related amphotropic retroviruses isolated from birds. These viruses exhibit several highly unusual characteristics that have not so far been adequately explained, including their extremely close relationship to mammalian retroviruses, and their presence as endogenous sequences within the genomes of certain large DNA viruses. We present evidence for an iatrogenic origin of REVs that accounts for these phenomena. Firstly, we identify endogenous retroviral fossils in mammalian genomes that share a unique recombinant structure with REVs—unequivocally demonstrating that REVs derive directly from mammalian retroviruses. Secondly, through sequencing of archived REV isolates, we confirm that contaminated Plasmodium lophurae stocks have been the source of multiple REV outbreaks in experimentally infected birds. Finally, we show that both phylogenetic and historical evidence support a scenario wherein REVs originated as mammalian retroviruses that were accidentally introduced into avian hosts in the late 1930s, during experimental studies of P. lophurae, and subsequently integrated into the fowlpox virus (FWPV) and gallid herpesvirus type 2 (GHV-2) genomes, generating recombinant DNA viruses that now circulate in wild birds and poultry. Our findings provide a novel perspective on the origin and evolution of REV, and indicate that horizontal gene transfer between virus families can expand the impact of iatrogenic transmission events
The deuteron: structure and form factors
A brief review of the history of the discovery of the deuteron in provided.
The current status of both experiment and theory for the elastic electron
scattering is then presented.Comment: 80 pages, 33 figures, submited to Advances in Nuclear Physic
Evaluation of an online interactive Diabetes Needs Assessment Tool (DNAT) versus online self-directed learning: a randomised controlled trial
<p>Abstract</p> <p>Background</p> <p>Methods for the dissemination, understanding and implementation of clinical guidelines need to be examined for their effectiveness to help doctors integrate guidelines into practice. The objective of this randomised controlled trial was to evaluate the effectiveness of an interactive online Diabetes Needs Assessment Tool (DNAT) (which constructs an e-learning curriculum based on individually identified knowledge gaps), compared with self-directed e-learning of diabetes guidelines.</p> <p>Methods</p> <p>Health professionals were randomised to a 4-month learning period and either given access to diabetes learning modules alone (control group) or DNAT plus learning modules (intervention group). Participants completed knowledge tests before and after learning (primary outcome), and surveys to assess the acceptability of the learning and changes to clinical practice (secondary outcomes).</p> <p>Results</p> <p>Sixty four percent (677/1054) of participants completed both knowledge tests. The proportion of nurses (5.4%) was too small for meaningful analysis so they were excluded. For the 650 doctors completing both tests, mean (SD) knowledge scores increased from 47.4% (12.6) to 66.8% (11.5) [intervention group (n = 321, 64%)] and 47.3% (12.9) to 67.8% (10.8) [control group (n = 329, 66%)], (ANCOVA p = 0.186). Both groups were satisfied with the usability and usefulness of the learning materials. Seventy seven percent (218/284) of the intervention group reported combining the DNAT with the recommended reading materials was "<it>very useful"/"useful"</it>. The majority in both groups (184/287, 64.1% intervention group and 206/299, 68.9% control group) [95% CI for the difference (-2.8 to 12.4)] reported integrating the learning into their clinical practice.</p> <p>Conclusions</p> <p>Both groups experienced a similar and significant improvement in knowledge. The learning materials were acceptable and participants incorporated the acquired knowledge into practice.</p> <p>Trial registration</p> <p>ISRCTN: <a href="http://www.controlled-trials.com/ISRCTN67215088">ISRCTN67215088</a></p
The aged niche disrupts muscle stem cell quiescence
SUMMARY The niche is a conserved regulator of stem cell quiescence and function. During aging, stem cell function declines. To what extent and by which means age-related changes within the niche contribute to this phenomenon are unknown. We demonstrate that the aged muscle stem cell niche, the muscle fiber, expresses FGF2 under homeostatic conditions, driving a subset of satellite cells to break quiescence and lose self-renewing capacity. We show that relatively dormant aged satellite cells robustly express Sprouty1 (spry1), an inhibitor of FGF signalling. Increasing FGF signalling in aged satellite cells under homeostatic conditions by removing spry1, results in the loss of quiescence, satellite cell depletion and diminished regenerative capacity. Conversely, reducing niche-derived FGF activity through inhibition of FGFR1 signalling or overexpression of spry1 in satellite cells prevents their depletion. These experiments identify an age-dependent change in the stem cell niche that directly influences stem cell quiescence and function
Diffractive Dijet Production at sqrt(s)=630 and 1800 GeV at the Fermilab Tevatron
We report a measurement of the diffractive structure function of
the antiproton obtained from a study of dijet events produced in association
with a leading antiproton in collisions at GeV at the
Fermilab Tevatron. The ratio of at GeV to
obtained from a similar measurement at GeV is compared with
expectations from QCD factorization and with theoretical predictions. We also
report a measurement of the (-Pomeron) and ( of parton in
Pomeron) dependence of at GeV. In the region
, GeV and , is
found to be of the form , which obeys
- factorization.Comment: LaTeX, 9 pages, Submitted to Phys. Rev. Letter
- …