Finite-temperature relativistic Landau problem and the relativistic quantum Hall effect

This paper presents a study of the free energy and particle density of the relativistic Landau problem, and their relevance to the quantum Hall effect. We study first the zero temperature Casimir energy and fermion number for Dirac fields in a 2+1-dimensional Minkowski space-time, in the presence of a uniform magnetic field perpendicular to the spatial manifold. Then, we go to the finite-temperature problem, with a chemical potential, introduced as a uniform zero component of the gauge potential. By performing a Lorentz boost, we obtain Hall's conductivity in the case of crossed electric and magnetic fields.Comment: Final version, to appear in Journal of Physics A: Mathematical and Genera

Miscarriage following dengue virus 3 infection in the first six weeks of pregnancy of a dengue virus-naive traveller returning from Bali to Italy, April 2016

We report miscarriage following dengue virus (DENV)-3 infection in a pregnant woman returning from Bali to Italy in April 2016. On her arrival, the woman had fever, rash, asthenia and headache. DENV RNA was detected in plasma and urine samples collected the following day. Six days after symptom onset, she had a miscarriage. DENV RNA was detected in fetal material, but in utero fetal infection cannot be demonstrated due to possible contamination by maternal blood

Oversubscribing inotify on Embedded Platforms

For most computers running the popular Linux operating system, the inte- grated kernel component inotify provides adequate functionality for monitor- ing changes to files present on the filesystem. However, for certain embedded platforms where resources are very limited and filesystems are very populated (like network attached storage (NAS) devices), inotify may not have enough resources to provide watchers for every file. This results in applications missing change notifications for files they have watched. This paper explores methods for using inotify most effectively on embedded systems by leveraging more la- tent storage. Benefits of this include a reduction in dropped notifications in favor of an introduced delay on notifications for files that are less frequently changed

Shedding light on the elusive role of endothelial cells in cytomegalovirus dissemination.

Cytomegalovirus (CMV) is frequently transmitted by solid organ transplantation and is associated with graft failure. By forming the boundary between circulation and organ parenchyma, endothelial cells (EC) are suited for bidirectional virus spread from and to the transplant. We applied Cre/loxP-mediated green-fluorescence-tagging of EC-derived murine CMV (MCMV) to quantify the role of infected EC in transplantation-associated CMV dissemination in the mouse model. Both EC- and non-EC-derived virus originating from infected Tie2-cre(+) heart and kidney transplants were readily transmitted to MCMV-naïve recipients by primary viremia. In contrast, when a Tie2-cre(+) transplant was infected by primary viremia in an infected recipient, the recombined EC-derived virus poorly spread to recipient tissues. Similarly, in reverse direction, EC-derived virus from infected Tie2-cre(+) recipient tissues poorly spread to the transplant. These data contradict any privileged role of EC in CMV dissemination and challenge an indiscriminate applicability of the primary and secondary viremia concept of virus dissemination

Ultra-fast photocatalytic degradation of Rhodamine B exploiting oleate-stabilized zinc oxide nanoparticles

Rhodamine B (RhB) is a harmful dye released by industrial wastewaters, thus necessitating its urgent removal. Advanced oxidation processes constitute promising strategies to purify polluted water. Among others, photocatalysis relies on reac- tive oxygen species (ROS) produced by photocatalytic particles, typically semiconductors like titania or zinc oxide (ZnO), excited by solar or UV–Vis light. However, their wide band gap limits their catalytic capabilities within the absorption of the UV spectrum and causes fast electron–hole recombination. This study presents novel strategies to overcome these limitations: (i) doping semiconductors to increase photocatalytic efficiency; (ii) sensitization-mediated photocatalysis for visible light activation using chemical moieties to trap dye molecules; (iii) nanosizing the photocatalysts to enhance the surface area. ZnO nanoparticles, doped with iron or gadolinium and capped with oleic acid are here synthesized and tested in RhB dye solutions. Remarkably, the results demonstrate an ultra-fast RhB degradation, driven by oleic acid hav- ing crucial role in dye adsorption. The degradation mechanisms, including ROS-induced N-deethylation and xanthene group cleavage, are also unraveled. These findings underscore the efficacy of the proposed semiconductor photocatalyst design, highlighting a significant advancement with extensive potential applications in wastewater remediation. This innovative approach paves the way for more efficient and practical solutions to combat industrial dye pollution

Virucidal effect against Coronavirus SARS-CoV-2 of a silver nanocluster/silica composite sputtered coating

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Tratado do espaço de 1967 : legado e desafios para o direito espacial.

O presente trabalho tem por objetivo, à luz do Direito Internacional, estudar o Tratado do Espaço de 1967, enquanto norma estruturadora do regime internacional para o espaço exterior, destacando-se seu legado e os desafios com os quais se depara o Direito Espacial atualmente, analisados sob a perspectiva da referida convenção. No tocante à metodologia, elege-se o método dedutivo, utilizando-se de extensiva pesquisa bibliográfica. No primeiro capítulo do trabalho, é realizado o estudo da evolução história do Direito Espacial, que se confunde com a história da própria ¿Era Espacial¿, inaugurada com o lançamento do Sputnik I em 1957; no mesmo capítulo são estudados, também, os cinco tratados que formam o corpus iuris do Direito Internacional. No segundo capítulo, o Tratado do Espaço de 1967 é abordado por intermédio de precisa análise de seus dispositivos sob à ótica do Direito Internacional. São analisados a cláusula do bem comum, o princípio da não-apropriação, a desmilitarização do espaço, os astronautas, a responsabilidade dos Estados por danos causados no espaço exterior e as perspectivas de cooperação no e para o espaço. Por derradeiro, o terceiro capítulo traz os desafios do Direito Espacial no século XXI analisados à luz do Tratado do Espaço de 1967. O estudo paira sobre a questão da delimitação da fronteira entre espaço aéreo e exterior, lixo espacial e a exploração de recursos naturais e a participação de empresas privadas. Conclui-se que ainda que relevante para o Direito Espacial, atendendo às demandas postas à época, o Tratado do Espaço de 1967 não mais consegue dar resposta a estes e outros desafios que lhe são impostos atualmente.This work aims, in the light of International Law, to study the Outer Space Treaty, as structuring instrument of the international regime for outer space; highlighting its legacy and the challenges that are currently faced by Space Law, analyzed from the perspective of the Convention. In regard to the methodology, it was elected the deductive method, using extensive literature search. In the first chapter, the historical development of Space Law is studied, which is intertwined with the history of the ""Space Age"" itself, wich began with the launch of Sputnik I in 1957; in the same chapter the five treaties that combined form the corpus iuris of International Law are also studied. In the second chapter, the Outer Space Treaty is approached by a precise analysis of its devices under the perspective of Internacional Law. The common good clause, the principle of non-appropriation, the demilitarization of space, the astronauts, States¿ responsibility for damage caused by space activities and the prospects of cooperation in and to Space are analyzed. Lastly, the third chapter brings the challenges of Space Law in the twenty-first century analyzed in the light of Outer Space Treaty. The study is based on the delimitation of bordes¿s issue between air and outer space, space debris and the exploitation of natural resources and the participation of private companies. It is concluded that although relevant to Space Law, meeting the demands placed at the time, the 1967¿s Outer Space Treaty is no longer able to meet these and other challenges that are currently imposed

Genetic divergence of influenza A NS1 gene in pandemic 2009 H1N1 isolates with respect to H1N1 and H3N2 isolates from previous seasonal epidemics

<p>Abstract</p> <p>Background</p> <p>The Influenza A pandemic sustained by a new H1N1 variant (H1N1v) started in Mexico and the USA at the end of April 2009 spreading worldwide in a few weeks. In this study we investigate the variability of the NS1 gene of the pandemic H1N1v strain with respect to previous seasonal strains circulating in humans and the potential selection of virus variants through isolation in cell culture.</p> <p>Methods</p> <p>During the period April 27^th2009-Jan 15^th2010, 1633 potential 2009 H1N1v cases have been screened at our center using the CDC detection and typing realtime RT-PCR assays. Virus isolation on MDCK cells was systematically performed in 1/10 positive cases. A subset of 51 H1N1v strains isolated in the period May-September 2009 was selected for NS1 gene sequencing. In addition, 15 H1N1 and 47 H3N2 virus isolates from three previous seasonal epidemics (2006-2009) were analyzed in parallel.</p> <p>Results</p> <p>A low variability in the NS1 amino acid (aa) sequence among H1N1v isolates was shown (aa identity 99.5%). A slightly higher NS1 variability was observed among H1N1 and H3N2 strains from previous epidemics (aa identity 98.6% and 98.9%, respectively). The H1N1v strains were closely related (aa identity 92.1%) to swine reference strain (A/swine/Oklahoma/042169/2008). In contrast, substantial divergence (aa identity 83.4%) with respect to human reference strain A/Brevig Mission/1/1918 and previous epidemic strains H1N1 and H3N2 (aa identity 78.9% and 77.6%, respectively) was shown. Specific sequence signatures of uncertain significance in the new virus variant were a C-terminus deletion and a T215P substitution.</p> <p>Conclusions</p> <p>The H1N1v NS1 gene was more conserved than that of previous epidemic strains. In addition, a closer genetic identity of H1N1v with the swine than the human reference strains was shown. Hot-spots were shown in the H1N1v NS1 aa sequence whose biologic relevance remains to be investigated.</p

Artificial and Naturally Derived Phospholipidic Bilayers as Smart Coatings of Solid-State Nanoparticles: Current Works and Perspectives in Cancer Therapy

Recent advances in nanomedicine toward cancer treatment have considered exploiting liposomes and extracellular vesicles as effective cargos to deliver therapeutic agents to tumor cells. Meanwhile, solid-state nanoparticles are continuing to attract interest for their great medical potential thanks to their countless properties and possible applications. However, possible drawbacks arising from the use of nanoparticles in nanomedicine, such as the nonspecific uptake of these materials in healthy organs, their aggregation in biological environments and their possible immunogenicity, must be taken into account. Considering these limitations and the intrinsic capability of phospholipidic bilayers to act as a biocompatible shield, their exploitation for effectively encasing solid-state nanoparticles seems a promising strategy to broaden the frontiers of cancer nanomedicine, also providing the possibility to engineer the lipid bilayers to further enhance the therapeutic potential of such nanotools. This work aims to give a comprehensive overview of the latest developments in the use of artificial liposomes and naturally derived extracellular vesicles for the coating of solid-state nanoparticles for cancer treatment, starting from in vitro works until the up-to-date advances and current limitations of these nanopharmaceutics in clinical applications, passing through in vivo and 3D cultures studies