A model for the ESR-STM phenomenon

We propose a model to account for the observed ESR-like signal at the Larmor frequency in the current noise STM experiments identifying spin centers on various substrates. The theoretical understanding of this phenomenon, which allows for single spin detection on surfaces at room temperature, is not settled for the experimentally relevant case that the tip and substrate are not spin polarized. Our model is based on a direct tip-substrate tunneling in parallel with a current flowing via the spin states. We find a sharp signal at the Larmor frequency even at high temperatures, in good agreement with experimental data. We also evaluate the noise in presence of an ac field near resonance and predict splitting of the signal by the Rabi frequency.Comment: 5 pages, 3 figure

Local and Effective Temperatures of Quantum Driven Systems

We introduce thermometers to define the local temperature of an electronic system driven out-of-equilibrium by local AC fields. We also define the effective temperature in terms of a local fluctuation-dissipation-relation. We show that within the weak driving regime these two temperatures coincide. We also discuss the behavior of the local temperature along the sample. We show that it exhibits spatial fluctuations following an oscillatory pattern. For weak driving, regions of the sample become heated, while others become cooled as a consequence of the driving

Relation Between Local Temperature Gradients and the Direction of Heat Flow in Quantum Driven Systems

We introduce thermometers to define the local temperature of an electronic system driven out-of-equilibrium by local ac fields. We discuss the behavior of the local temperature along the sample, showing that it exhibits spatial fluctuations following an oscillatory pattern. We show explicitly that the local temperature is the correct indicator for heat flow.Comment: 3 pages, 2 figure

A note on the existence of soliton solutions in the Chern-Simons-CP(1) model

We study a gauged Chern-Simons-CP(1) system. We show that contrary to previous claims the model in the absences of a potential term cannot support finite size soliton solution in $R^2$.Comment: 12 pages, 5 figure

Durability Assessment of GFRP Rebars Exposed to High pH-Seawater

There is a continued process to implement innovative materials to enhance the sustainability and durability of the built infrastructure. Technologies developed over the last two decades have facilitated the use of glass fiber reinforced polymer (GFRP) composites as internal reinforcement bars (rebars) for concrete structures, which have proven to be an alternative to traditional steel reinforcement due to significant advantages, such as magnetic transparency and, most importantly, corrosion resistance, equating to durability and structural life extension. This study evaluates the durability of three different available and most commonly used GFRP rebar types, based on exposure to aggressive environments, such as those experienced in coastal areas. For that, the specimens were expose to high pH seawater solution (that simulates the alkalinity of the concrete exposed to seawater), at 60 ºC for different periods of time: 45, 90, and 180 days. The durability of these GFRP rebars was assessed by testing four different physio-mechanical properties, including: tensile strength, elastic modulus, and transverse and horizontal shear strength. Preliminary results show that the resilience of the GFRP rebars after being exposed to high pH seawater at high temperature, varies considerably among the three different types. The tensile strength was the most affected physio-mechanical property

Palcayaco watershed management through environmental zoning in Huancavelica, Peru

The technical and integrated participation of the population in environmental zoning and soil and water conservation techniques and management is a sustainable alternative for watershed management. The objective of the research was to develop an environmental zoning map for the Palcayaco watershed in Huancavelica, Peru (from its socioeconomic aspects to its technical recommendations). The research work was deductive, where all the necessary data were delimited, described, inventoried, recapitulated and extracted to describe the morphometric parameters, biophysical and socioeconomic situation, environmental zoning and techniques for soil and water conservation. Results: the watershed was perennial, an average slope of 29.65%, a time of concentration of 180.6 min and a balanced hypsometric curve type (B). It also had low population density, unpaved roads, scarce basic services, and poor education and health services infrastructure. The watershed presented different ecoregions, life zones, climatic classification and altitudinal sector, current land use for agricultural, livestock and silvopastoral production, steep type, forest pasture use and protection capacity. The conflict area was in good use, and economic-ecological zoning was in protection, conservation, recovery, water, productive, and urban-industrial. The environmental zoning designed for the Palcayaco watershed preserved the most important natural resources for rural communities, improving their biophysical and socioeconomic status. Through soil and water conservation techniques and management, it will prevent the degradation of the watershed for a better and sustainable future.             

High Prevalence of Mycoplasma pneumoniae and Chlamydia pneumoniae in Children with Acute Respiratory Infections from Lima, Peru

Background Mycoplasma pneumoniae and Chlamydia pneumoniae are atypical pathogens responsible for pneumonia and a leading cause of morbidity and mortality in low income countries. The study objective is to determine the prevalence of this pathogens in Peruvian children with acute respiratory infections. Methods A consecutive cross-sectional study was conducted in Lima, Peru from May 2009 to September 2010. A total of 675 children admitted with clinical diagnoses of acute respiratory infections were tested for Mycoplasma pneumoniae and Chlamydia pneumoniae detection by polymerase chain reaction (PCR), and clinical symptoms were registered by the attending physician. Results Mycoplasma pneumonia was detected in 25.19% (170/675) of nasopharyngeal samples and Chlamydia pneumonia in 10.52% (71/675). The most common symptoms in patients with these atypical pathogens were rhinorrhea, cough and fever. A higher prevalence of Mycoplasma pneumoniae cases were registered in summer, between December 2009 and March 2010. Conclusions Mycoplasma pneumoniae and Chlamydia pneumonia are a significant cause of morbidity in Peruvian children with acute respiratory infections (ARI). Further studies should evaluate the use of reliable techniques such as PCR in Peru in order to avoid underdiagnoses of these atypical pathogens

Spatiotemporal Characteristics of the Largest HIV-1 CRF02_AG Outbreak in Spain: Evidence for Onward Transmissions

Background and Aim: The circulating recombinant form 02_AG (CRF02_AG) is the predominant clade among the human immunodeficiency virus type-1 (HIV-1) non-Bs with a prevalence of 5.97% (95% Confidence Interval-CI: 5.41–6.57%) across Spain. Our aim was to estimate the levels of regional clustering for CRF02_AG and the spatiotemporal characteristics of the largest CRF02_AG subepidemic in Spain.Methods: We studied 396 CRF02_AG sequences obtained from HIV-1 diagnosed patients during 2000–2014 from 10 autonomous communities of Spain. Phylogenetic analysis was performed on the 391 CRF02_AG sequences along with all globally sampled CRF02_AG sequences (N = 3,302) as references. Phylodynamic and phylogeographic analysis was performed to the largest CRF02_AG monophyletic cluster by a Bayesian method in BEAST v1.8.0 and by reconstructing ancestral states using the criterion of parsimony in Mesquite v3.4, respectively.Results: The HIV-1 CRF02_AG prevalence differed across Spanish autonomous communities we sampled from (p < 0.001). Phylogenetic analysis revealed that 52.7% of the CRF02_AG sequences formed 56 monophyletic clusters, with a range of 2–79 sequences. The CRF02_AG regional dispersal differed across Spain (p = 0.003), as suggested by monophyletic clustering. For the largest monophyletic cluster (subepidemic) (N = 79), 49.4% of the clustered sequences originated from Madrid, while most sequences (51.9%) had been obtained from men having sex with men (MSM). Molecular clock analysis suggested that the origin (tMRCA) of the CRF02_AG subepidemic was in 2002 (median estimate; 95% Highest Posterior Density-HPD interval: 1999–2004). Additionally, we found significant clustering within the CRF02_AG subepidemic according to the ethnic origin.Conclusion: CRF02_AG has been introduced as a result of multiple introductions in Spain, following regional dispersal in several cases. We showed that CRF02_AG transmissions were mostly due to regional dispersal in Spain. The hot-spot for the largest CRF02_AG regional subepidemic in Spain was in Madrid associated with MSM transmission risk group. The existence of subepidemics suggest that several spillovers occurred from Madrid to other areas. CRF02_AG sequences from Hispanics were clustered in a separate subclade suggesting no linkage between the local and Hispanic subepidemics

The Agentes de Indias: Transatlantic Lobbying and the Representation of Spanish-American Interests in Madrid, c. 1776-1820

Between 1778 and 1817, the Spanish crown issued 100 royal titles of Agentes de Indias to an equal number of men who lived in Madrid. While the number of recipients of these titles is far from negligible, those who were on the receiving end and what did they do remains, to a large extent, unknown. This dissertation is the most significant effort to date to shed light on these Agentes de Indias and their “system.” The Agentes, this dissertation establishes, were more than the holders of an empty shell of a title. Instead, this thesis shows how the Agentes constituted themselves as the mainstay representatives of colonial interests before the central institutions of the Spanish crown for Indies’ affairs in a professionalized capacity. This dissertation establishes so using an array of primary sources collected through archival research in several South American countries, and multiple archives in Spain. This evidentiary corpus is interpreted from Agentes’ perspective as historical actors invested in representing Indies-related matters (negocios de Indias) as a way to make a living. However, the dissertation does not consider the Agentes’ professional endeavors as a self-explanatory enterprise. Instead, it draws broader meaning from the experience of the Agentes by situating this system in the historiographies of European and Spanish absolutism, the Bourbon reforms in the Americas, and the age of revolutions in the Hispanic Atlantic. By envisioning the Agentes as actors invested in making a livelihood from furnishing royal decisions produced in Madrid to ambitious clients in the Indies, the dissertation positions them at the crux of intra-imperial relations. The Agentes role as intermediaries in crown-subjects relations constituted itself as all the more relevant as the Spanish Empire navigated the resistance elicited by new taxes imposed in the 1780s, as crown officials wrestled with the consequences of foreign wars and fear of revolutionary expansion in the 1790s, and as monarchical legitimacy experienced a deep crisis in the Americas after 1810