Groundwater modeling based on scarce data: the case of Patiño Aquifer in Paraguay

This study aims to contribute to the understanding of the groundwater flow dynamics and to obtain a robust base line for further transient state simulations, studying different conditions in terms of aquifer boundaries, and taking into consideration the trend of very low variability observed for water levels between 2007 and 2015.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Development of a low-cost and open-source autonomous surface vehicle for waste stabilization pond monitoring

The underperformance of existing wastewater treatment systems represents a constant threat to the environment and public health. The generalized lack of water quantity and quality monitoring data in developing countries makes decision-makers unaware of the current performance of wastewater treatment systems. In ongoing research, a prototype of a low-cost and open-source Autonomous Surface Vehicle (ASV) for monitoring the treatment performance of WSP was developed. The ASV is capable of navigating autonomously along a predefined trajectory based on geographic coordinates, and, meanwhile, performing measurements at different locations within the pond. The challenging circumstances inherent to wastewater management in developing countries were taken into account during the design and construction. The open-source nature allows to integrate any type of sensor according to user needs. The ASV can be applied as a low-cost and flexible tool for a variety of WSP monitoring applications.CONACYT - Consejo Nacional de Ciencia y TecnologíaPROCIENCI

Effects of spatial and temporal variability of rainfall on urban hydrological models

"The working hypothesis is that as fewer gauges are used to interpolate a rain event there will be more error. Preliminary results indicate that high rain events produce much more error, around 300% relative error. It is also seen that the bigger the watershed the bigger the errors – this is mainly due to the fact that larger storms are associated with a larger variance and reducing the number of gauges used reduced the information provided to the model. Future work will focus on calibrating the model with field data and developing robust mechanism in order to properly choose which gauges to keep and what type of averaging and interpolating conditions should be used. "CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Optimization of a groundwater quality campaign utilizing the NSGA-II with preference ordering algorithm, contamination risk maps and well availability.

This work focused in selecting 70 wells to conduct a groundwater quality sampling campaign. The wells were selected using 4 objectis: contamination risk of NT and CT, the coverage area and the wells which are publicly accessible. A Multiobjective Optimization Problem was defined to obtain the possible selections, and the Nondominated Sorting Genetic Algorithm II with Preference Ordering was implemented to solve it. The proposed solutions allowed the selection of 70 wells, 86% correspond to the wells which are publicly accessible, 70% of the wells are located in places with the high indices of contamination risk and cover 74% of the study area.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Optimization of an urban rain gauge network utilizing different PCA-Variable identification techniques

"In order to study the effects of urban runoff, through numerical models and the design of waterworks, appropriate rainfall information needs to be gathered and analyzed. With this purpose a 27 rain gauge network has been deployed over the AMA. Here we present a principal component analysis (PCA) on daily rainfall data collected from June 2016 to December 2017 in order identify the stations that should be kept in place, given the objective of accurately capturing the spatial variability of rainfall over the Metropolitan Area of Asuncion."CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Multi-Objective Optimization for the Selection of Wells for a Water Monitoring Campaign of the Patiño Aquifer, Paraguay.

Presentación en evento internacional sobre investigación referentes a la calidad de las aguas subterráneas del Acuifero Patiño.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI

Discrete Wigner functions and the phase space representation of quantum teleportation

We present a phase space description of the process of quantum teleportation for a system with an $N$ dimensional space of states. For this purpose we define a discrete Wigner function which is a minor variation of previously existing ones. This function is useful to represent composite quantum system in phase space and to analyze situations where entanglement between subsystems is relevant (dimensionality of the space of states of each subsystem is arbitrary). We also describe how a direct tomographic measurement of this Wigner function can be performed.Comment: 8 pages, 1 figure, to appear in Phys Rev

Quantum computers in phase space

We represent both the states and the evolution of a quantum computer in phase space using the discrete Wigner function. We study properties of the phase space representation of quantum algorithms: apart from analyzing important examples, such as the Fourier Transform and Grover's search, we examine the conditions for the existence of a direct correspondence between quantum and classical evolutions in phase space. Finally, we describe how to directly measure the Wigner function in a given phase space point by means of a tomographic method that, itself, can be interpreted as a simple quantum algorithm.Comment: 16 pages, 7 figures, to appear in Phys Rev

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Do`s and dont`s of installing and maintaining an urban rain gaugenetwork

As an overall lesson, we present a list of Do’s and Don'ts so that future researchers interested in carrying out an urban rainfall collection campaign with rain gauges start out better advised and pay appropriate heed to the most important issues. The list of tips presented is not exhaustive by any means and each urban location surely has specific issues that are intrinsic to them.CONACYT - Consejo Nacional de Ciencias y TecnologíaPROCIENCI