642 research outputs found
Non-topological condensates for the self-dual Chern-Simons-Higgs model
For the abelian self-dual Chern-Simons-Higgs model we address existence
issues of periodic vortex configurations -- the so-called condensates-- of
non-topological type as , where is the Chern-Simons parameter.
We provide a positive answer to the long-standing problem on the existence of
non-topological condensates with magnetic field concentrated at some of the
vortex points (as a sum of Dirac measures) as , a question which is of
definite physical interest.Comment: accepted on Comm. Pure Appl. Mat
Interplay between CFTR Phosphorylation, CFTR-ATPase Activity, and Anion Flux
The cystic fibrosis (CF) transmembrane conductance regulator (CFTR, ABCC7), mutations of which cause CF, belongs to the ATP binding cassette (ABC) transporter family and works as a channel for small anions, such as chloride and bicarbonate. Anion channel activity is known to depend on phosphorylation by cAMP-dependent protein kinase A (PKA) and CFTR-ATPase activity. Whereas anion channel activity has been extensively investigated, phosphorylation and CFTR-ATPase activity are still poorly understood. Here, we show that the two processes can be measured in a label-free and non-invasive manner in real time in live cells, stably transfected with CFTR. This study reveals three key findings. (i) The major contribution to the total CFTR-related ATP hydrolysis rate (≥ 90 %) is due to phosphorylation by PKA and the minor contribution (≤ 10 %) to CFTR-ATPase activity. (ii) The mutant CFTR-E1371S which is still conductive, but defective in ATP hydrolysis, is not phosphorylated, suggesting that phosphorylation requires a functional nucleotide binding domain and occurs in the post-hydrolysis transition state. (iii) CFTR-ATPase activity is inversely related to CFTR anion flux. The present data are consistent with a model in which CFTR is in a closed conformation with two ATPs bound. The open conformation is induced by ATP hydrolysis and corresponds to the post hydrolysis transition state which is stabilized by phosphorylation and binding of chloride channel potentiators
Laparoscopic extravesical ureteral reimplantation (LEVUR): A systematic review
Abstract
BACKGROUND:
Laparoscopic ureteral reimplantation is a feasible method for treating ureteral pathology with good preliminary results in the literature. In this study, we review medium term results for laparoscopic ureteral reimplantation and discuss current developments of this procedure.
METHODS:
Medline and Embase databases were searched using relevant key terms to identify reports of paediatric laparoscopic extravesical ureteral reimplantation (LEVUR). Literature reviews, case reports, series of 20 years) were excluded.
RESULTS:
Five studies were assessed, overall, 69 LEVUR were performed in children. Despite different surgical technique, in all case the technique was respected. Patient demographics, preoperative symptoms, radiological imaging, complications, and postoperative outcomes were analyzed. Median success rate was 96%. Complications were reported in five cases.
CONCLUSIONS:
This study is limited by the data given in the individual series: varied criteria used for patient selection and outcome as well as inconsistent pre- and post-operative imaging data precluded a meta-analysis. But it demonstrates that the laparoscopic ureteral reimplantation is an effective procedure with good medium-term results. We believe that in well selected patients this procedure will become an established treatment option
Tannin-modified soybean protein concentrate for wood adhesive
[EN] Soybean protein concentrate (SPC) modified with condensed mimosa tannin (CT) were employed as eco-friendly and formaldehyde-free adhesives for glued-wood joints. Eucalyptus grandis wood boards free of knots and cracks were used as substrate. Thermogravimetric analysis (TGA) showed that tannin provided higher thermal stability to the adhesive, which allowed expanding the temperature range for hot pressing. Apparent viscosity and dynamic angle contact were measured to evaluate the influence of tannin content on rheological behaviour and the wettability process. A classic shear-thinning behaviour was observed for all adhesives. Apparent viscosity and equilibrium contact angle reached a maximum value for low CT content. This effect was attributed to the existence of associative interactions between CT and SPC. Bonding quality parameters (wood failure percentage and shear strength) of the glued-wood joints were measured according to EN 302-1:2004 standard. 1 % CT w/w on SPC adhesive showed the best performance for dry conditions. These adhesives were suitable for glued-wood joints for indoor environments.This work was supported by the Agencia Nacional de promociĂłn CientĂfica y TecnolĂłgica (ANPCyT) under Grant PICT 2016 0445; Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas (CONICET); Universidad Nacional de Mar del Plata (UNMdP). A special thanks to Mr. Cesar Bovino (Aserradero Ubajay) for providing the wood.Esposito, L.; Ciannamea, EM.; Solaberrieta, I.; Piter, JC.; Ruseckaite, RA.; Stefani, PM. (2022). Tannin-modified soybean protein concentrate for wood adhesive. Journal of Applied Research in Technology & Engineering. 3(1):1-7. https://doi.org/10.4995/jarte.2022.15962OJS1731Aydin, I., & Colakoglu, G. (2007). Variation in surface roughness, wettability and some plywood properties after preservative treatment with boron compounds. Building and Environment, 42(11), 3837-3840. https://doi.org/10.1016/j.buildenv.2006.11.009Cheng, E., Sun, X., (2006) Effects of wood-surface roughness, adhesive viscosity and processing pressure on adhesion strength of protein adhesives. Journal of Adhesion Science and Technology 20, 997-1017. https://doi.org/10.1163/156856106777657779Ciannamea, E. M., Stefani, P. M., & Ruseckaite, R. A. (2010). Medium-density particleboards from modified rice husks and soybean protein concentrate-based adhesives. Bioresource Technology, 101(2), 818-825. https://doi.org/10.1016/j.biortech.2009.08.084Ciannamea, E. M., Martucci, J. F., Stefani, P. M., Ruseckaite, R. A. (2012). Bonding Quality of Chemically-Modified Soybean Protein Concentrate-Based Adhesives in Particleboards from Rice Husks. Journal of the American Oil Chemists' Society, 89(9), 1733-1741. https://doi.org/10.1007/s11746-012-2058-2Ciannamea E M, Marin D C, Ruseckaite R A and Stefani P M (2017) Particleboard based on rice husk: effect of binder content and processing conditions J. Renew. Mater 5 19-22. https://doi.org/10.7569/JRM.2017.634125Chalapud, M. C.; Herdt, M.; Nicolao, E. S.; Ruseckaite, R. A.; Ciannamea, E. M.; Stefani, P. M. (2020). Biobased particleboards based on rice husk and soy proteins: Effect of the impregnation with tung oil on the physical and mechanical behavior. Constr Build Mater. 230: 116996. https://doi.org/10.1016/j.conbuildmat.2019.116996Damodaran, S.; Zhu, D. (2016) A formaldehyde-free water-resistant soy flour-based adhesive for plywood. J. Am. Oil. Chem. Soc. 93, 1311-1318. https://doi.org/10.1007/s11746-016-2866-xde Freitas, V., & Mateus, N. (2012). Protein/polyphenol interactions: past and present contributions. Mechanisms of astringency perception. Current Organic Chemistry, 16(6), 724-746. https://doi.org/10.2174/138527212799958002FAO (2019) http://www.fao.org/faostat/es/#data/QCGhahri, S., Pizzi, A., Mohebby, B., Mirshokraie, A., & Mansouri, H. R. (2017). Soy-based, tannin-modified plywood adhesives. The Journal of Adhesion, 94(3), 218-237. https://doi.org/10.1080/00218464.2016.1258310Ghahri, S., Pizzi, A., Mohebby, B., Mirshoktaie, A., Mansouri, H. R. (2018). Improving water resistance of soy-based adhesive by vegetable tannin. Journal of Polymers and the Environment, 26(5), 1881-1890. https://doi.org/10.1007/s10924-017-1090-6Ghahri, S.; Chen, X.; Pizzi,A.; Hajihassani, R.; Papadopoulos (2021) A.N. Natural Tannins as New Cross-Linking Materials for Soy-Based Adhesives. Polymers, 13, 595. https://doi.org/10.3390/polym13040595Hagenimana, A.; Ding X.; Gu W.Y. (2007), Steady state flow behaviors of extruded blend of rice flour and soy protein concentrate, Food Chemistry, 101, 241 - 247. https://doi.org/10.1016/j.foodchem.2006.01.043Hojilla-Evangelista, M. P. (2010). Adhesion properties of plywood glue containing soybean meal as an extender. Journal of the American Oil Chemists' Society, 87(9), 1047-1052. https://doi.org/10.1007/s11746-010-1586-xHunt, C. G.; Frihart, C. R.; Dunky, M.; Rohumaa, A. (2018). Understanding wood bonds-going beyond what meets the eye: a critical review. Reviews of Adhesion and Adhesives, 6(4), 369-440. https://doi.org/10.7569/RAA.2018.097312Jang, Y., Li, K. (2015). An All-Natural Adhesive for Bonding Wood. Journal of the American Oil Chemists' Society, 92(3), 431-438. https://doi.org/10.1007/s11746-015-2610-yKhosravi, S., Nordqvist, P., Khabbaz, F., Ă–hman, C., Bjurhager, I., & Johansson, M. (2015). Wetting and film formation of wheat gluten dispersions applied to wood substrates as particle board adhesives. European Polymer Journal, 67, 476-482. https://doi.org/10.1016/j.eurpolymj.2014.11.034Leiva, P., Ciannamea, E., Ruseckaite, R. A., & Stefani, P. M. (2007). Medium-density particleboards from rice husks and soybean protein concentrate. Journal of Applied Polymer Science, 106(2), 1301-1306. https://doi.org/10.1002/app.26545Lin, H., & Gunasekaran, S. (2010). Cow blood adhesive: Characterization of physicochemical and adhesion properties. International Journal of Adhesion and Adhesives, 30(3), 139-144. https://doi.org/10.1016/j.ijadhadh.2009.10.003Liu C, Zhang Y, Li X, Luo J, Gao Q, Li J,(2017) Green bio-thermoset resins derived from soy protein isolate and condensed tannins, Industrial Crops and Products, 108, 363-370. https://doi.org/10.1016/j.indcrop.2017.06.057Mo, X., Cheng, E., Wang, D., & Sun, X. S. (2003). Physical properties of medium-density wheat straw particleboard using different adhesives. Industrial Crops and Products, 18(1), 47-53. https://doi.org/10.1016/S0926-6690(03)00032-3Nicolao, E.; Leiva, P.; Chalapud, M.; Ruseckaite, R.; Ciannamea, E.; Stefani, P. (2020). Flexural and tensile properties of biobased rice husk-jute-soybean protein particleboards. J. Build. Eng.: 101261. https://doi.org/10.1016/j.jobe.2020.101261Nordqvist, P., Nordgren, N., Khabbaz, F., & Malmström, E. (2013). Plant proteins as wood adhesives: Bonding performance at the macro-and nanoscale. Industrial Crops and Products, 44, 246-252. https://doi.org/10.1016/j.indcrop.2012.11.021Ozdal, T., Capanoglu, E., & Altay, F. (2013). A review on protein-phenolic interactions and associated changes. Food Research International, 51(2), 954-970. https://doi.org/10.1016/j.foodres.2013.02.009Peña, C., De la Caba, K., Eceiza, A., Ruseckaite, R., & Mondragon, I. (2010). Enhancing water repellence and mechanical properties of gelatin films by tannin addition. 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On the Inequivalence of Renormalization and Self-Adjoint Extensions for Quantum Singular Interactions
A unified S-matrix framework of quantum singular interactions is presented
for the comparison of self-adjoint extensions and physical renormalization. For
the long-range conformal interaction the two methods are not equivalent, with
renormalization acting as selector of a preferred extension and regulator of
the unbounded Hamiltonian.Comment: 19 pages, including 2 figures. The title and abstract were changed to
more accurately reflect the content. The text was rearranged into sections,
with several equations and multiple paragraphs added for clarity; and a few
typos were corrected. The central equations and concepts remain unchanged
Surgical management of pediatric vesicoureteral reflux: A comparative study between endoscopic, laparoscopic, and open surgery
Our retrospective study compared the results of three surgical procedures for correction of pediatric vesicoureteral reflux (VUR): open Cohen, laparoscopic Lich-Gregoir reimplantation (LEVUR), and endoscopic subureteric injection (STING) procedure.
METHODS:
We analyzed 90 patients (50 girls, 40 boys, average age 4.86 years) operated in two centers of pediatric surgery for VUR. Exclusion criteria were Grade 1 VUR, Grade 5 VUR with megaureters requiring ureteral tapering, secondary VUR, and patients already operated for VUR. Thirty patients underwent Cohen, 30 LEVUR, and 30 STING procedure. Follow-up included renal ultrasonography and voiding cystourethrography 6 months postoperatively. The statistical analysis was performed using χ(2) Pearson and Fisher tests.
RESULTS:
Operative time was shorter using STING either for unilateral or bilateral correction (P = .001). Hospitalization was statistically shorter using STING and LEVUR compared to Cohen (P = .001). The pain scores were worse after Cohen (P = .001). Analgesic requirements were higher after Cohen (P = .001). Reflux persistence was higher after STING (10 cases versus 5 Cohen and 4 LEVUR). Cohen presented more complications compared to LEVUR and STING (P = .001). Intraoperative costs were higher for STING procedure (P = .001), while hospitalization costs were significantly higher for Cohen procedure (P = .001).
CONCLUSIONS:
In children affected by VUR, open Cohen and LEVUR reported a higher success rate than STING procedure. However, Cohen procedure had a very long and painful hospital stay, more complications, more analgesic requirements compared to STING and LEVUR. Comparing the three techniques, it seems that LEVUR presents a high success rate similar to the Cohen procedure, but in addition, it presents the same advantages of STING procedure with no postoperative pain and a lower postoperative morbidity
A scanning probe investigation of the role of surface motifs in the behavior of p-WSe_2 photocathodes
The spatial variation in the photoelectrochemical performance for the reduction of an aqueous one-electron redox couple, Ru(NH_3)_6^(3+/2+), and for the evolution of H_2(g) from 0.5 M H_2SO_4(aq) at the surface of bare or Pt-decorated p-type WSe_2 photocathodes has been investigated in situ using scanning photocurrent microscopy (SPCM). The measurements revealed significant differences in the charge-collection performance (quantified by the values of external quantum yields, Φ_(ext)) on various macroscopic terraces. Local spectral response measurements indicated a variation in the local electronic structure among the terraces, which was consistent with a non-uniform spatial distribution of sub-band-gap states within the crystals. The photoconversion efficiencies of Pt-decorated p-WSe_2 photocathodes were greater for the evolution of H_2(g) from 0.5 M H_2SO_4 than for the reduction of Ru(NH_3)_6^(3+/2+), and terraces that exhibited relatively low values of Φ_(ext) for the reduction of Ru(NH_3)_6^(3+/2+) could in some cases yield values of Φ_(ext) for the evolution of H_2(g) comparable to the values of Φ_(ext) yielded by the highest-performing terraces. Although the spatial resolution of the techniques used in this work frequently did not result in observation of the effect of edge sites on photocurrent efficiency, some edge effects were observed in the measurements; however the observed edge effects differed among edges, and did not appear to determine the performance of the electrodes
Quantum collisional thermostats
Collisional reservoirs are becoming a major tool for modelling open quantum systems. In their simplest implementation, an external agent switches on, for a given time, the interaction between the system and a specimen from the reservoir. Generically, in this operation the external agent performs work onto the system, preventing thermalization when the reservoir is at equilibrium. One can recover thermalization by considering an autonomous global setup where the reservoir particles colliding with the system possess a kinetic degree of freedom. The drawback is that the corresponding scattering problem is rather involved. Here, we present a formal solution of the problem in one dimension and for flat interaction potentials. The solution is based on the transfer matrix formalism and allows one to explore the symmetries of the resulting scattering map. One of these symmetries is micro-reversibility, which is a condition for thermalization. We then introduce two approximations of the scattering map that preserve these symmetries and, consequently, thermalize the system. These relatively simple approximate solutions constitute models of quantum thermostats and are useful tools to study quantum systems in contact with thermal baths. We illustrate their accuracy in a specific example, showing that both are good approximations of the exact scattering problem even in situations far from equilibrium. Moreover, one of the models consists of the removal of certain coherences plus a very specific randomization of the interaction time. These two features allow one to identify as heat the energy transfer due to switching on and off the interaction. Our results prompt the fundamental question of how to distinguish between heat and work from the statistical properties of the exchange of energy between a system and its surroundings
Towards conversational technology to promote, monitor and protect mental health
This paper presents a general overview of the H2020-MSCA-RISE project MENHIR (Mental health monitoring through interactive conversations), which aim is to explore the possibilities of conversational technologies (chatbots) to understand, promote and protect mental health and assist people with anxiety and mild depression manage their conditions. MENHIR started on February 2019 and will have a duration of 4 years. Its consortium brings together 8 partners including universities, anon-profit organization and companies
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