11,317 research outputs found

    Electromagnetic quasinormal modes of five-dimensional topological black holes

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    We calculate exactly the QNF of the vector type and scalar type electromagnetic fields propagating on a family of five-dimensional topological black holes. To get a discrete spectrum of quasinormal frequencies for the scalar type electromagnetic field we find that it is necessary to change the boundary condition usually imposed at the asymptotic region. Furthermore for the vector type electromagnetic field we impose the usual boundary condition at the asymptotic region and we discuss the existence of unstable quasinormal modes in the five-dimensional topological black holes.Comment: 16 pages. Already published in Revista Mexicana de Fisic

    Rhodium complexes in p-C bond formation: Key role of a hydrido ligand

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    Olefin hydrophosphanation is an attractive route for the atom-economical synthesis of functionalized phosphanes. This reaction involves the formation of P-C and H-C bonds. Thus, complexes that contain both hydrido and phosphanido functionalities are of great interest for the development of effective and fast catalysts. Herein, we showcase the excellent activity of one of them, [Rh(Tp)H(PMe3)(PPh2)] (1), in the hydrophosphanation of a wide range of olefins. In addition to the required nucleophilicity of the phosphanido moiety to accomplish the P-C bond formation, the key role of the hydride ligand in 1 has been disclosed by both experimental results and DFT calculations. An additional Rh-H··· C stabilization in some intermediates or transition states favors the hydrogen transfer reaction from rhodium to carbon to form the H-C bond. Further support for our proposal arises from the poor activity exhibited by the related chloride complex [Rh(Tp)Cl(PMe3)(PPh2)] as well as from stoichiometric and kinetic studies

    Firm-local community relationships in polluting industrial agglomerations: How firms' commitment determines residents' perceptions

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    This research contributes to the literature on the management of firm–local community relationships in polluting industrial agglomerations. Taking as reference a previous quantitative study on residents' perceptions of economic benefits and risk in the vicinity of two Spanish petrochemical complexes (Castellón and Tarragona), the aim of this paper is to analyse how companies in the two areas have built and manage, individually and collectively, their relations with the local community, while assessing the extent to which a more committed management has resulted in a more favourable perception by the public. For this purpose, we conducted in-depth interviews with managers of the main companies on the two sites. The results show different patterns of behaviour by firms in the two industrial agglomerations. Companies located in the area of Tarragona, where citizens' perceptions were more favourable, have historically been more committed to building stronger socio-economic links with the local community and encouraging a sense of community, and to making greater efforts to engage local residents through a process of dialogue. Moreover, the existence of a collective strategy in Tarragona, coordinated through a local industry association, has also played an important role in facilitating the industry's relationship with the local community. The findings of the study suggest the need to consider the industrial agglomeration and the firms' collective actions in research on relationships with the local community alongside actions by individual companies

    Renormalized stress-energy tensor for spin-1/2 fields in expanding universes

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    We provide an explicit expression for the renormalized expectation value of the stress-energy tensor of a spin-1/2 field in a spatially flat Friedmann-Lemaitre-Robertson-Walker universe. Its computation is based on the extension of the adiabatic regularization method to fermion fields introduced recently in the literature. The tensor is given in terms of UV-finite integrals in momentum space, which involve the mode functions that define the quantum state. As illustrative examples of the method efficiency, we see how to compute the renormalized energy density and pressure in two interesting cosmological scenarios: a de Sitter spacetime and a radiation-dominated universe. In the second case, we explicitly show that the late-time renormalized stress-energy tensor behaves as that of classical cold matter. We also check that, if we obtain the adiabatic expansion of the scalar field mode functions with a similar procedure to the one used for fermions, we recover the well-known WKB-type expansion

    Effects of fat and/or methionine hydroxy analog added to a molasses-urea-based supplement on ruminal and postruminal digestion and duodenal flow of nutrients in beef steers consuming low-quality lovegrass hay

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    Five crossbred beef steers (initial BW = 338.6 ± 7.8 kg) fitted with ruminal and duodenal cannulas were used in a 5 × 5 Latin square design experiment to evaluate the effects of methionine hydroxy analog (MHA) and/or yellow grease (fat) added to a molassesurea- based supplement on intake and characteristics of digestion. Steers were fed low-quality hay (long-stem lovegrass Eragrostis curvula: 3.3% CP, 76.8% NDF; DM basis) ad libitum and supplemented with 0.91 kg/d (as fed) of 1 of 4 supplements in a 2 × 2 + 1 factorial arrangement of treatments. Supplemental treatments were 1) control (no supplement, NC); 2) molassesurea liquid supplement (U); 3) U containing (as-fed basis) 1.65% MHA (UM); 4) U containing (as-fed basis) 12% fat (UF); and 5) U containing (as-fed basis) 1.65% MHA and 12% fat (UMF). Total and forage OM intake (kg/d and as % of BW) increased (P \u3c 0.01) with molasses-urea, decreased (P ≤ 0.04) with MHA, and were not affected (P = 0.61) with fat supplementation. Total tract NDF digestibility increased (P = 0.01) with molasses-urea supplementation, and was less (P = 0.01) for fat than for nonfat supplementation. Total and microbial N flowing to the duodenum increased (P = 0.01) with molasses-urea supplementation. Although, total N flowing to duodenum was not affected (P = 0.27), microbial N decreased (P = 0.01), and nonammonia nonmicrobial N (NANMN) increased (P = 0.01) with fat supplementation. Extent of in situ OM and NDF digestibility at 96 h increased (P = 0.01) with molasses-urea supplementation, but were not affected (P ≥ 0.14) by either MHA or fat supplementation. Duodenal flow of total AA, essential AA, and nonessential AA increased (P ≤ 0.02) with molasses-urea supplementation. Total and nonessential serum AA concentration decreased (P \u3c 0.01) with molasses-urea supplementation. Total ruminal VFA concentration increased (P = 0.01) with molasses-urea supplementation, and was not affected (P ≥ 0.14) by MHA or fat supplementation. Fat can be used in molasses-urea liquid supplements for cattle consuming low-quality forage to increase energy intake without negatively affecting forage intake or characteristics of digestion. However, adding MHA did not further improve the response to urea supplementation of cattle consuming low-quality forage. Conversely, the inclusion of MHA on urea supplement decreased forage intake

    Amyloid-β reduces the expression of neuronal FAIM-L, thereby shifting the inflammatory response mediated by TNFα from neuronal protection to death

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    The brains of patients with Alzheimer’s disease (AD) present elevated levels of tumor necrosis factor-α (TNFα), a cytokine that has a dual function in neuronal cells. On one hand, TNFα can activate neuronal apoptosis, and on the other hand, it can protect these cells against amyloid-β (Aβ) toxicity. Given the dual behavior of this molecule, there is some controversy regarding its contribution to the pathogenesis of AD. Here we examined the relevance of the long form of Fas apoptotic inhibitory molecule (FAIM) protein, FAIM-L, in regulating the dual function of TNFα. We detected that FAIM-L was reduced in the hippocampi of patients with AD. We also observed that the entorhinal and hippocampal cortex of a mouse model of AD (PS1M146LxAPP751sl) showed a reduction in this protein before the onset of neurodegeneration. Notably, cultured neurons treated with the cortical soluble fractions of these animals showed a decrease in endogenous FAIM-L, an effect that is mimicked by the treatment with Aβ-derived diffusible ligands (ADDLs). The reduction in the expression of FAIM-L is associated with the progression of the neurodegeneration by changing the inflammatory response mediated by TNFα in neurons. In this sense, we also demonstrate that the protection afforded by TNFα against Aβ toxicity ceases when endogenous FAIM-L is reduced by short hairpin RNA (shRNA) or by treatment with ADDLs. All together, these results support the notion that levels of FAIM-L contribute to determine the protective or deleterious effect of TNFα in neuronal cells

    The intrinsic dimensionality of spectro-polarimetric data

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    The amount of information available in spectro-polarimetric data is estimated. To this end, the intrinsic dimensionality of the data is inferred with the aid of a recently derived estimator based on nearest-neighbor considerations and obtained applying the principle of maximum likelihood. We show in detail that the estimator correctly captures the intrinsic dimension of artificial datasets with known dimension. The effect of noise in the estimated dimension is analyzed thoroughly and we conclude that it introduces a positive bias that needs to be accounted for. Real simultaneous spectro-polarimetric observations in the visible 630 nm and the near-infrared 1.5 microns spectral regions are also investigated in detail, showing that the near-infrared dataset provides more information of the physical conditions in the solar atmosphere than the visible dataset. Finally, we demonstrate that the amount of information present in an observed dataset is a monotonically increasing function of the number of available spectral lines.Comment: 12 pages, 7 figures, accepted for publication in the Astrophysical Journa

    Randomized Clinical Trials of obesity treatments in Mexican population. Systematic Review and Meta-Analysis

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    Background: Mexicans and Mexican Americans share similar culture, genetic background, and predisposition for obesity and diabetes. Randomized clinical trials (RCT) assessing obesity treatments (ObT) are reliable to assess efficacy. To date, there is no systematic review to investigate ObT tested by RCT in Mexican adults. Methods: We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve ObT RCT from 1990 to 2019. The ObT included alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions. The analyzed RCT were at least three months of duration, and reported: BMI, weight, waist circumference, triglycerides, glucose and blood pressure. Results: We found 634 entries; after removal of duplicates and exclusions based on eligibility criteria, we analyzed 43 and 2 multinational-collaborative studies. Most of the national studies had small sample sizes, and did not have replications from other studies. The nutrition/behavioral interventions were difficult to blind, and most studies had medium to high risk of bias. Random effects meta-analysis of nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like plain water instead of sweet beverages decreased triglycerides and systolic blood pressure. Participants with obesity and hypertension had beneficial effects with antioxidants, and the treatment with insulin increased weight in those with T2D. Conclusions: The RCT’s in Mexico reported effects on metabolic components despite small sample sizes and lack of replication. In the future we should analyze ObT in population living on the U.S.-Mexico border; therefore, bi-national collaboration is desirable to disentangle cultural effects on ObT response

    A Novel Clinical and Stress Cardiac Magnetic Resonance (C-CMR-10) Score to Predict Long-Term All-Cause Mortality in Patients with Known or Suspected Chronic Coronary Syndrome

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    [EN] Vasodilator stress cardiac magnetic resonance (stressCMR) has shown robust diagnostic and prognostic value in patients with known or suspected chronic coronary syndrome (CCS). However, it is unknown whether integration of stressCMR with clinical variables in a simple clinical-imaging score can straightforwardly predict all-cause mortality in this population. We included 6187 patients in a large registry that underwent stressCMR for known or suspected CCS. Several clinical and stressCMR variables were collected, such as left ventricular ejection fraction (LVEF) and ischemic burden (number of segments with stress-induced perfusion defects (PD)). During a median follow-up of 5.56 years, we registered 682 (11%) all-cause deaths. The only independent predictors of all-cause mortality in multivariable analysis were age, male sex, diabetes mellitus (DM), LVEF and ischemic burden. Based on the weight of the chi-square increase at each step of the multivariable analysis, we created a simple clinical-stressCMR (C-CMR-10) score that included these variables (age >= 65 years = 3 points, LVEF 5 segments = 1 point). This 0 to 10 points C-CMR-10 score showed good performance to predict all-cause annualized mortality rate ranging from 0.29%/year (score = 0) to >4.6%/year (score >= 7). The goodness of the model and of the C-CMR-10 score was separately confirmed in 2 internal cohorts (n> 3000 each). We conclude that a novel and simple clinical-stressCMR score, which includes clinical and stressCMR variables, can provide robust prediction of the risk of long-term all-cause mortality in a population of patients with known or suspected CCS.This work was supported by the Instituto de Salud Carlos III and co-funded by Fondo Europeo de Desarrollo Regional (FEDER) (grant numbers PI17/01836 and CIBERCV16/11/00486).Marcos-Garces, V.; Gavara-Doñate, J.; Monmeneu-Menadas, JV.; Lopez-Lereu, MP.; Pérez, N.; Rios-Navarro, C.; De Dios, E.... (2020). A Novel Clinical and Stress Cardiac Magnetic Resonance (C-CMR-10) Score to Predict Long-Term All-Cause Mortality in Patients with Known or Suspected Chronic Coronary Syndrome. Journal of Clinical Medicine. 9(6):1-13. https://doi.org/10.3390/jcm9061957S11396Hendel, R. C., Friedrich, M. G., Schulz-Menger, J., Zemmrich, C., Bengel, F., Berman, D. S., … Nagel, E. (2016). CMR First-Pass Perfusion for Suspected Inducible Myocardial Ischemia. JACC: Cardiovascular Imaging, 9(11), 1338-1348. doi:10.1016/j.jcmg.2016.09.010Chang, S.-A., & Kim, R. J. (2016). The Use of Cardiac Magnetic Resonance in Patients with Suspected Coronary Artery Disease: A Clinical Practice Perspective. Journal of Cardiovascular Ultrasound, 24(2), 96. doi:10.4250/jcu.2016.24.2.96Kiaos, A., Tziatzios, I., Hadjimiltiades, S., Karvounis, C., & Karamitsos, T. D. (2018). Diagnostic performance of stress perfusion cardiac magnetic resonance for the detection of coronary artery disease. International Journal of Cardiology, 252, 229-233. doi:10.1016/j.ijcard.2017.11.066Li, M., Zhou, T., Yang, L., Peng, Z., Ding, J., & Sun, G. (2014). Diagnostic Accuracy of Myocardial Magnetic Resonance Perfusion to Diagnose Ischemic Stenosis With Fractional Flow Reserve as Reference. JACC: Cardiovascular Imaging, 7(11), 1098-1105. doi:10.1016/j.jcmg.2014.07.011Siontis, G. C., Mavridis, D., Greenwood, J. P., Coles, B., Nikolakopoulou, A., Jüni, P., … Windecker, S. (2018). Outcomes of non-invasive diagnostic modalities for the detection of coronary artery disease: network meta-analysis of diagnostic randomised controlled trials. BMJ, k504. doi:10.1136/bmj.k504Nagel, E., Greenwood, J. P., McCann, G. P., Bettencourt, N., Shah, A. M., Hussain, S. T., … Berry, C. (2019). Magnetic Resonance Perfusion or Fractional Flow Reserve in Coronary Disease. New England Journal of Medicine, 380(25), 2418-2428. doi:10.1056/nejmoa1716734Siontis, G. C., Branca, M., Serruys, P., Silber, S., Räber, L., Pilgrim, T., … Hunziker, L. (2019). Impact of left ventricular function on clinical outcomes among patients with coronary artery disease. European Journal of Preventive Cardiology, 26(12), 1273-1284. doi:10.1177/2047487319841939Buckert, D., Kelle, S., Buss, S., Korosoglou, G., Gebker, R., Birkemeyer, R., … Bernhardt, P. (2016). Left ventricular ejection fraction and presence of myocardial necrosis assessed by cardiac magnetic resonance imaging correctly risk stratify patients with stable coronary artery disease: a multi-center all-comers trial. Clinical Research in Cardiology, 106(3), 219-229. doi:10.1007/s00392-016-1042-5Catalano, O., Moro, G., Perotti, M., Frascaroli, M., Ceresa, M., Antonaci, S., … Priori, S. G. (2012). Late gadolinium enhancement by cardiovascular magnetic resonance is complementary to left ventricle ejection fraction in predicting prognosis of patients with stable coronary artery disease. Journal of Cardiovascular Magnetic Resonance, 14(1). doi:10.1186/1532-429x-14-29Lipinski, M. J., McVey, C. M., Berger, J. S., Kramer, C. M., & Salerno, M. (2013). Prognostic Value of Stress Cardiac Magnetic Resonance Imaging in Patients With Known or Suspected Coronary Artery Disease. Journal of the American College of Cardiology, 62(9), 826-838. doi:10.1016/j.jacc.2013.03.080Gargiulo, P., Dellegrottaglie, S., Bruzzese, D., Savarese, G., Scala, O., Ruggiero, D., … Filardi, P. P. (2013). The Prognostic Value of Normal Stress Cardiac Magnetic Resonance in Patients With Known or Suspected Coronary Artery Disease. Circulation: Cardiovascular Imaging, 6(4), 574-582. doi:10.1161/circimaging.113.000035Kwong, R. Y., Ge, Y., Steel, K., Bingham, S., Abdullah, S., Fujikura, K., … Simonetti, O. P. (2019). Cardiac Magnetic Resonance Stress Perfusion Imaging for Evaluation of Patients With Chest Pain. Journal of the American College of Cardiology, 74(14), 1741-1755. doi:10.1016/j.jacc.2019.07.074Marcos-Garces, V., Gavara, J., Monmeneu, J. V., Lopez-Lereu, M. P., Bosch, M. J., Merlos, P., … Bodi, V. (2020). Vasodilator Stress CMR and All-Cause Mortality in Stable Ischemic Heart Disease. JACC: Cardiovascular Imaging, 13(8), 1674-1686. doi:10.1016/j.jcmg.2020.02.027Heitner, J. F., Kim, R. J., Kim, H. W., Klem, I., Shah, D. J., Debs, D., … Judd, R. M. (2019). Prognostic Value of Vasodilator Stress Cardiac Magnetic Resonance Imaging. JAMA Cardiology, 4(3), 256. doi:10.1001/jamacardio.2019.0035Bodi, V., Sanchis, J., Lopez-Lereu, M. P., Nunez, J., Mainar, L., Monmeneu, J. V., … Llacer, A. (2007). Prognostic Value of Dipyridamole Stress Cardiovascular Magnetic Resonance Imaging in Patients With Known or Suspected Coronary Artery Disease. Journal of the American College of Cardiology, 50(12), 1174-1179. doi:10.1016/j.jacc.2007.06.016Bodi, V., Husser, O., Sanchis, J., Núñez, J., Monmeneu, J. V., López-Lereu, M. P., … Llacer, Á. (2012). Prognostic Implications of Dipyridamole Cardiac MR Imaging: A Prospective Multicenter Registry. Radiology, 262(1), 91-100. doi:10.1148/radiol.11110134Ponikowski, P., Voors, A. A., Anker, S. D., Bueno, H., Cleland, J. G. F., Coats, A. J. S., … van der Meer, P. (2016). 2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure. European Heart Journal, 37(27), 2129-2200. doi:10.1093/eurheartj/ehw128Marschner, I. C., Colquhoun, D., Simes, R. J., Glasziou, P., Harris, P., Singh, B. B., … Tonkin, A. (2001). Long-term risk stratification for survivors of acute coronary syndromes. Journal of the American College of Cardiology, 38(1), 56-63. doi:10.1016/s0735-1097(01)01360-2Knuuti, J., Wijns, W., Saraste, A., Capodanno, D., Barbato, E., Funck-Brentano, C., … Cuisset, T. (2019). 2019 ESC Guidelines for the diagnosis and management of chronic coronary syndromes. European Heart Journal, 41(3), 407-477. doi:10.1093/eurheartj/ehz425Klem, I., Shah, D. J., White, R. D., Pennell, D. J., van Rossum, A. C., Regenfus, M., … Kim, R. J. (2011). Prognostic Value of Routine Cardiac Magnetic Resonance Assessment of Left Ventricular Ejection Fraction and Myocardial Damage. Circulation: Cardiovascular Imaging, 4(6), 610-619. doi:10.1161/circimaging.111.964965Grothues, F., Smith, G. C., Moon, J. C. ., Bellenger, N. G., Collins, P., Klein, H. U., & Pennell, D. J. (2002). Comparison of interstudy reproducibility of cardiovascular magnetic resonance with two-dimensional echocardiography in normal subjects and in patients with heart failure or left ventricular hypertrophy. The American Journal of Cardiology, 90(1), 29-34. doi:10.1016/s0002-9149(02)02381-0Timmis, A., Raharja, A., Archbold, R. A., & Mathur, A. (2018). Validity of inducible ischaemia as a surrogate for adverse outcomes in stable coronary artery disease. Heart, 104(21), 1733-1738. doi:10.1136/heartjnl-2018-313230Pontone, G., Andreini, D., Bertella, E., Loguercio, M., Guglielmo, M., Baggiano, A., … Masci, P. G. (2015). Prognostic value of dipyridamole stress cardiac magnetic resonance in patients with known or suspected coronary artery disease: a mid-term follow-up study. European Radiology, 26(7), 2155-2165. doi:10.1007/s00330-015-4064-xHeydari, B., Juan, Y.-H., Liu, H., Abbasi, S., Shah, R., Blankstein, R., … Kwong, R. Y. (2016). Stress Perfusion Cardiac Magnetic Resonance Imaging Effectively Risk Stratifies Diabetic Patients With Suspected Myocardial Ischemia. Circulation: Cardiovascular Imaging, 9(4). doi:10.1161/circimaging.115.004136Vincenti, G., Masci, P. G., Monney, P., Rutz, T., Hugelshofer, S., Gaxherri, M., … Schwitter, J. (2017). Stress Perfusion CMR in Patients With Known and Suspected CAD. JACC: Cardiovascular Imaging, 10(5), 526-537. doi:10.1016/j.jcmg.2017.02.006Buckert, D., Cieslik, M., Tibi, R., Radermacher, M., Rottbauer, W., & Bernhardt, P. (2017). Cardiac magnetic resonance imaging derived quantification of myocardial ischemia and scar improves risk stratification and patient management in stable coronary artery disease. Cardiology Journal, 24(3), 293-304. doi:10.5603/cj.a2017.0036Zemrak, F., & Petersen, S. E. (2011). Late Gadolinium Enhancement CMR Predicts Adverse Cardiovascular Outcomes and Mortality in Patients With Coronary Artery Disease: Systematic Review and Meta-Analysis. Progress in Cardiovascular Diseases, 54(3), 215-229. doi:10.1016/j.pcad.2011.07.003El Aidi, H., Adams, A., Moons, K. G. M., Den Ruijter, H. M., Mali, W. P. T. M., Doevendans, P. A., … Leiner, T. (2014). Cardiac Magnetic Resonance Imaging Findings and the Risk of Cardiovascular Events in Patients With Recent Myocardial Infarction or Suspected or Known Coronary Artery Disease. Journal of the American College of Cardiology, 63(11), 1031-1045. doi:10.1016/j.jacc.2013.11.048Fox, K. A. A., Metra, M., Morais, J., & Atar, D. (2019). The myth of ‘stable’ coronary artery disease. Nature Reviews Cardiology, 17(1), 9-21. doi:10.1038/s41569-019-0233-ySchiele, F., Ecarnot, F., & Chopard, R. (2017). Coronary artery disease: Risk stratification and patient selection for more aggressive secondary prevention. European Journal of Preventive Cardiology, 24(3_suppl), 88-100. doi:10.1177/2047487317706586Fordyce, C. B., Douglas, P. S., Roberts, R. S., Hoffmann, U., Al-Khalidi, H. R., … Patel, M. R. (2017). Identification of Patients With Stable Chest Pain Deriving Minimal Value From Noninvasive Testing. JAMA Cardiology, 2(4), 400. doi:10.1001/jamacardio.2016.5501Papireddy, M. R., Lavie, C. J., Deoker, A., Mamudu, H., & Paul, T. K. (2018). New Algorithm for the Prediction of Cardiovascular Risk in Symptomatic Adults with Stable Chest Pain. Current Cardiology Reports, 20(5). doi:10.1007/s11886-018-0973-
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