The 2020 Covid-19 pandemic and global value chains

This paper considers the impact of the Covid-19 pandemic on firm strategies and, in particular, the configuration of firms’ global value chains (GVCs) once the pandemic has been brought under control. The merits of alternative location strategies (international diversification vs reshoring) are compared, as are the merits of different governance arrangements (internalization vs externalization) for GVC activities. The possibility of fire-sale foreign direct investment is raised, and the wider geopolitical context is emphasized. The widespread human tragedy is noted, as is the dilemma facing national governments around the world in balancing lives and livelihoods

A Right Atrial Hemangioma Mimicking Thrombus In A Patient With Atrial Arrhythmias

Cardiac hemangiomas are rare tumors, accounting for only 2.8% of all benign primary cardiac tumors and occur at any age. Clinical presentations vary depending on the tumor location (myocardial, endocardial or pericardial). In many cases, this may be an incidental finding. We report the case of a patient with paroxysmal atrial fibrillation who had a right atrial hemangioma detected with transesophageal echocardiography prior to having percutaneous pulmonary vein isolation performe

Acoustic cloak based on Bézier scatterers

[EN] Among the different approaches proposed to design acoustic cloaks, the one consisting on the use of an optimum distribution of discrete scatters surrounding the concealing object has been successfully tested. The feasibility of acoustic cloaks mainly depends on the number and shape of the scatterers surrounding the object to be cloaked. This work presents a method allowing the reduction of the number of discrete scatterers by optimizing their external shape, which is here defined by a combination of cubic Bézier curves. Based on scattering cancellation, a two-dimensional directional cloak consisting of just 20 Bézier scatters has been designed, fabricated and experimentally characterized. The method of fundamental solutions has been implemented to calculate the interaction of an incident plane wave with scatterers of arbitrary shape. The acoustic cloak here proposed shows a performance, in terms of averaged visibility, similar to that consisting of 120 scatterers with equal circular cross sections. The operational frequency of the proposed cloak is 5940 Hz with a bandwidth of about 110 Hz.J. Sanchez-Dehesa acknowledges the financial support by the Spanish Ministerio de Economia y Competitividad and the European Union Fondo Europeo para el Desarrollo Regional (FEDER) under Grant with Ref. TEC2014-53088-C3-1-R. Lu Zhimiao acknowledges the financial support from the program of China Scholarships Council (No. 201503170282), Wen Jihong, Cai Li and Lu Zhimiao acknowledge the support by National Natural Science Foundation of China (Grant Nos 51275519 and 11372346)Lu, Z.; Sanchis Martínez, L.; Wen, J.; Cai, L.; Bi, Y.; Sánchez-Dehesa Moreno-Cid, J. (2018). Acoustic cloak based on Bézier scatterers. Scientific Reports. 8. https://doi.org/10.1038/s41598-018-30888-7S8Cummer, S. A. & Schurig, D. One path to acoustic cloaking. 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L., Boisvert, J. E. & Howarth, T. R. Acoustic cloaking using layered pentamode materials. J. Acoust. Soc. Am. 127(5), 2856–2864 (2010).Chen, Y. et al. Broadband solid cloak for underwater acoustics. Phys. Rev. B 95, 180104 May (2017).Alù, A. & Engheta, N. Achieving transparency with plasmonic and metamaterial coatings. Phys. Rev. E 72(1), 016623 (2005).Guild, M. D., Alu, A. & Haberman, M. R. Cancellation of acoustic scattering from an elastic sphere. J. Acoust. Soc. Am. 129(3), 1355–1365 (2011).García-Chocano, V. M. et al. Acoustic cloak for airborne sound by inverse design. Appl. Phys. Lett. 99(7), 074102 (2011).Sanchis, L. et al. Three-Dimensional Axisymmetric Cloak Based on the Cancellation of Acoustic Scattering from a Sphere. Phys. Rev. Lett. 110, 124301 Mar (2013).Andkjær, J. & Sigmund, O. Topology optimized for Airborne sound. ASME J. Vib. Acoust. 135(2), 041011 (2013).Guild, M. D. Acoustic Cloaking of Spherical Objects Unsing Thin Elastic Coatings. Univ. of Texas at Austin (2012).Guild, M. D., Haberman, M. R. & Alú, A. Plasmonic-type Acoustic cloak made of a bilaminate shell. Phys. Rev. B 86(10), 104302 (2012).Rohde, C. A. et al. Experimental demonstration of underwater acoustic scattering cancellation. Sci. Rep. 5, 13175 (2015).Popa, B.-I. & Cummer, S. A. Cloaking with optimized homogeneous anisotropic layers. Phys. Rev. A 79, 023806 Feb (2009).Urzhumov, Y., Landy, N., Driscoll, T., Basov, D. & Smith, D. R. Thin low-loss dielectric coatings for freespace cloaking. Opt. Lett. 38(10), 1606–1608 (2013).Andkjaer, J. & Sigmund, O. Topology optimized low-contrast all-dielectric optical cloak. Appl. Phys. Lett. 98(2), 021112 (2011).Climente, A., Torrent, D. & Sánchez-Dehesa, J. Sound focusing by gradient index sonic lenses. Applied Physics Letters 97(10), 104103 (2010).Håkansson, A., Sánchez-Dehesa, J. & Sanchis, L. Acoustic lens design by genetic algorithms Phys. Rev. B 70, 214302 Dec (2004).Håkansson, A., Cervera, F. & Sánchez-Dehesa, J. Sound focusing by flat acoustic lenses without negative refraction. Applied Physics Letters 86(5), 054102 (2005).Li, D., Zigoneanu, L., Popa, B.-I. & Cummer, S. A. Design of an acoustic metamaterial lens using genetic algorithms. The Journal of the Acoustical Society of America 132(4), 2823–2833 (2012).Prautzsch, H., Wolfgang Boehm, W. & Paluszny, M. Bézier and B-Spline Techniques. Springer Science & Business Media (2002).Andersen, P. R., Cutanda-Henríquez, V., Aage, N. & Sánchez-Dehesa, J. Viscothermal effects on an acoustic cloak based on scattering cancellation. Proceedings of the 6th International Conference on Noise and Vibration Emerging methods (NOVEM 2018 ), 171971, June (2018).Golberg, D. Genetic Algorithms in Search, Optimization and Learning. Addison Wesley, Reading, MA (1989).Kirkpatrick, S., Gelatt, C. D. & Vecchi, M. P. Optimization by simulated annealing. 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Attachment, infidelity, and loneliness in college students involved in a romantic relationship: the role of relationship satisfaction, morbidity and prayer for partner

This study examined the mediating effects of relationship satisfaction, prayer for a partner, and morbidity in the relationship between attachment and loneliness, infidelity and loneliness, and psychological morbidity and loneliness, in college students involved in a romantic relationship. Participants were students in an introductory course on family development. This study examined only students (n = 345) who were involved in a romantic relationship. The average age of participants was 19.46 (SD = 1.92) and 25 % were males. Short-form UCLA Loneliness Scale (ULS-8), (Hays and DiMatteo in J Pers Assess 51:69–81, doi:10.1207/s15327752jpa5101_6, 1987); Relationship Satisfaction Scale (Funk and Rogge in J Fam Psychol 21:572–583, doi:10.1037/0893-3200.21.4.572, 2007); Rotterdam Symptom Checklist (De Haes et al. in Measuring the quality of life of cancer patients with the Rotterdam Symptom Checklist (RSCL): a manual, Northern Centre for Healthcare Research, Groningen, 1996); Prayer for Partner Scale, (Fincham et al. in J Pers Soc Psychol 99:649–659, doi:10.1037/a0019628, 2010); Infidelity Scale, (Drigotas et al. in J Pers Soc Psychol 77:509–524, doi:10.1037/0022-3514.77.3.509, 1999); and the Experiences in Close Relationship Scale-short form (Wei et al. in J Couns Psychol 52(4):602–614, doi:10.1037/0022-0167.52.4.602, 2005). Results showed that relationship satisfaction mediated the relationship between avoidance attachment and loneliness and between infidelity and loneliness. Physical morbidity mediated the relationship between anxious attachment and psychological morbidity. Psychological morbidity mediated the relationship between anxious attachment and physical morbidity. The present results expand the literature on attachment by presenting evidence that anxious and avoidant partners experience loneliness differently. Implications for couple’s therapy are addressed. Future research should replicate these results with older samples and married couples.Acknowledgments This research was supported by Grant Number 90FE0022 from the United States Department of Health and Human Services awarded to the last author

Cryptosporidium Priming Is More Effective than Vaccine for Protection against Cryptosporidiosis in a Murine Protein Malnutrition Model

Cryptosporidium is a major cause of severe diarrhea, especially in malnourished children. Using a murine model of C. parvum oocyst challenge that recapitulates clinical features of severe cryptosporidiosis during malnutrition, we interrogated the effect of protein malnutrition (PM) on primary and secondary responses to C. parvum challenge, and tested the differential ability of mucosal priming strategies to overcome the PM-induced susceptibility. We determined that while PM fundamentally alters systemic and mucosal primary immune responses to Cryptosporidium, priming with C. parvum (106 oocysts) provides robust protective immunity against re-challenge despite ongoing PM. C. parvum priming restores mucosal Th1-type effectors (CD3+CD8+CD103+ T-cells) and cytokines (IFNγ, and IL12p40) that otherwise decrease with ongoing PM. Vaccination strategies with Cryptosporidium antigens expressed in the S. Typhi vector 908htr, however, do not enhance Th1-type responses to C. parvum challenge during PM, even though vaccination strongly boosts immunity in challenged fully nourished hosts. Remote non-specific exposures to the attenuated S. Typhi vector alone or the TLR9 agonist CpG ODN-1668 can partially attenuate C. parvum severity during PM, but neither as effectively as viable C. parvum priming. We conclude that although PM interferes with basal and vaccine-boosted immune responses to C. parvum, sustained reductions in disease severity are possible through mucosal activators of host defenses, and specifically C. parvum priming can elicit impressively robust Th1-type protective immunity despite ongoing protein malnutrition. These findings add insight into potential correlates of Cryptosporidium immunity and future vaccine strategies in malnourished children

Why simulation can be efficient: on the preconditions of efficient learning in complex technology based practices

<p>Abstract</p> <p>Background</p> <p>It is important to demonstrate learning outcomes of simulation in technology based practices, such as in advanced health care. Although many studies show skills improvement and self-reported change to practice, there are few studies demonstrating patient outcome and societal efficiency.</p> <p>The objective of the study is to investigate if and why simulation can be effective and efficient in a hi-tech health care setting. This is important in order to decide whether and how to design simulation scenarios and outcome studies.</p> <p>Methods</p> <p>Core theoretical insights in Science and Technology Studies (STS) are applied to analyze the field of simulation in hi-tech health care education. In particular, a process-oriented framework where technology is characterized by its devices, methods and its organizational setting is applied.</p> <p>Results</p> <p>The analysis shows how advanced simulation can address core characteristics of technology beyond the knowledge of technology's functions. Simulation's ability to address skilful device handling as well as purposive aspects of technology provides a potential for effective and efficient learning. However, as technology is also constituted by organizational aspects, such as technology status, disease status, and resource constraints, the success of simulation depends on whether these aspects can be integrated in the simulation setting as well. This represents a challenge for future development of simulation and for demonstrating its effectiveness and efficiency.</p> <p>Conclusion</p> <p>Assessing the outcome of simulation in education in hi-tech health care settings is worthwhile if core characteristics of medical technology are addressed. This challenges the traditional technical versus non-technical divide in simulation, as organizational aspects appear to be part of technology's core characteristics.</p

A Comparison of Online versus On-site Training in Health Research Methodology: A Randomized Study

<p>Abstract</p> <p>Background</p> <p>Distance learning may be useful for building health research capacity. However, evidence that it can improve knowledge and skills in health research, particularly in resource-poor settings, is limited. We compared the impact and acceptability of teaching two distinct content areas, Biostatistics and Research Ethics, through either on-line distance learning format or traditional on-site training, in a randomized study in India. Our objective was to determine whether on-line courses in Biostatistics and Research Ethics could achieve similar improvements in knowledge, as traditional on-site, classroom-based courses.</p> <p>Methods</p> <p><it>Subjects: </it>Volunteer Indian scientists were randomly assigned to one of two arms.</p> <p><it>Intervention: </it>Students in Arm 1 attended a 3.5-day on-site course in Biostatistics and completed a 3.5-week on-line course in Research Ethics. Students in Arm 2 attended a 3.5-week on-line course in Biostatistics and 3.5-day on-site course in Research Ethics. For the two course formats, learning objectives, course contents and knowledge tests were identical.</p> <p><it>Main Outcome Measures: </it>Improvement in knowledge immediately and 3-months after course completion, compared to baseline.</p> <p>Results</p> <p>Baseline characteristics were similar in both arms (n = 29 each). Median knowledge score for Biostatistics increased from a baseline of 49% to 64% (p < 0.001) 3 months after the on-site course, and from 48% to 63% (p = 0.009) after the on-line course. For the on-site Research Ethics course, median score increased from 69% to 83% (p = 0.005), and for the on-line Research Ethics course from 62% to 80% (p < 0.001). Three months after the course, median gains in knowledge scores remained similar for the on-site and on-line platforms for both Biostatistics (16% vs. 12%; p = 0.59) and Research Ethics (17% vs. 13%; p = 0.14).</p> <p>Conclusion</p> <p>On-line and on-site training formats led to marked and similar improvements of knowledge in Biostatistics and Research Ethics. This, combined with logistical and cost advantages of on-line training, may make on-line courses particularly useful for expanding health research capacity in resource-limited settings.</p

A mathematical and computational review of Hartree-Fock SCF methods in Quantum Chemistry

We present here a review of the fundamental topics of Hartree-Fock theory in Quantum Chemistry. From the molecular Hamiltonian, using and discussing the Born-Oppenheimer approximation, we arrive to the Hartree and Hartree-Fock equations for the electronic problem. Special emphasis is placed in the most relevant mathematical aspects of the theoretical derivation of the final equations, as well as in the results regarding the existence and uniqueness of their solutions. All Hartree-Fock versions with different spin restrictions are systematically extracted from the general case, thus providing a unifying framework. Then, the discretization of the one-electron orbitals space is reviewed and the Roothaan-Hall formalism introduced. This leads to a exposition of the basic underlying concepts related to the construction and selection of Gaussian basis sets, focusing in algorithmic efficiency issues. Finally, we close the review with a section in which the most relevant modern developments (specially those related to the design of linear-scaling methods) are commented and linked to the issues discussed. The whole work is intentionally introductory and rather self-contained, so that it may be useful for non experts that aim to use quantum chemical methods in interdisciplinary applications. Moreover, much material that is found scattered in the literature has been put together here to facilitate comprehension and to serve as a handy reference.Comment: 64 pages, 3 figures, tMPH2e.cls style file, doublesp, mathbbol and subeqn package

Evolution of Female Preference for Younger Males

Previous theoretical work has suggested that females should prefer to mate with older males, as older males should have higher fitness than the average fitness of the cohort into which they were born. However, studies in humans and model organisms have shown that as males age, they accumulate deleterious mutations in their germ-line at an ever-increasing rate, thereby reducing the quality of genes passed on to the next generation. Thus, older males may produce relatively poor-quality offspring. To better understand how male age influences female mate preference and offspring quality, we used a genetic algorithm model to study the effect of age-related increases in male genetic load on female mate preference. When we incorporate age-related increases in mutation load in males into our model, we find that females evolve a preference for younger males. Females in this model could determine a male's age, but not his inherited genotype nor his mutation load. Nevertheless, females evolved age-preferences that led them to mate with males that had low mutation loads, but showed no preference for males with respect to their somatic quality. These results suggest that germ-line quality, rather than somatic quality, should be the focus of female preference in good genes models