El abastecimiento con agua subterránea a la Colonia Clunia Sulpicia (Hispania Citerior Tarraconensis).

Hace 20 siglos, una autoridad romana fundó una ciudad en lo alto de un cerro testigo donde el hallazgo, por habilidad o casualidad, de un pequeño acuífero permitió el abastecimiento de agua. En época romana se perforaron pozos, de los que diecinueve llegaron a una cavidad natural. También se abrió una galería horizontal, para captar agua, y un drenaje en el teatro para eliminar aguas que molestaban. En algún momento, por razones naturales o artificiales, el nivel freático bajó y varios pozos se secaron, obligando al descenso de trabajadores y otras personas. Además de hacer obras complementarias dejaron abundantes grafitis y varias figuritas en barro en la cueva. La ciudad no sobrevive a la Edad Media, los pozos son cegados y las ruinas sufren un proceso de expolio por las localidades vecinas. Recuperada su memoria en el siglo XVIII, en 1908 se redescubre cueva Román, una antigua galería de captación que da acceso a la cueva natural. Esta es explorada y topografiada por el grupo Espeleológico Ribereño desde 1980. A partir de 2013, el Grupo de Tecnologías en Entornos hostiles, de la Universidad de Zaragoza, realiza radiolocalizaciones sistemáticas para la apertura de un acceso directo a la cavidad. Además, se han hecho reconocimientos de inscripciones con escaneos de la cavidad y detalles específicos así como la instalación de dos estaciones de monitorización, exterior e interior, para analizar el funcionamiento hídrico del sistema y la evolución interior del contenido en CO2 del aire de la cavidad. La evolución del nivel piezométrico presenta oscilaciones relativamente importantes y se detecta un retraso de dos meses entre los momentos de fuertes lluvias y el ascenso. El contenido en CO2 presenta una doble periodicidad, anual y diaria. Twenty centuries ago, a Roman authority founded a city on top of an inselberg where the discovery, by skill or chance, of a small aquifer which allowed access to a water supply for the city. In Roman times wells were drilled, of which nineteen reached a natural cavity. A horizontal gallery for water supply was also opened up, and a drainage conduct in the theatre was made to eliminate storm water. At some point, for natural or artificial reasons, the water table dropped and several wells dried up, forcing the descent of workers and other people to do additional work and to carve abundant graffiti and several clay figurines. The city did not survive the Middle Ages, the wells became cesspits and the ruins were plundered by neighbouring villages. It recovered its memory in the eighteenth century, in 1908 a Roman cave was rediscovered, the old water supply gallery, which gives access to the natural cave. This has been explored and surveyed by the Grupo Espeleológico Ribereño since 1980. From 2013, the Grupo de Technologías in Entornos Hostiles (University of Zaragoza) has carried out systematic radiolocation for the opening up of a direct access to the cavity. In addition, recognition of inscriptions with cavity scans and specific details have been made as well as the installation of two monitoring stations, both inside and outside the cavity to analyze the water performance of the system and the internal evolution of the CO2 content of the air in the cavity. The evolution of the piezometric level presents relatively important oscillations and a delay of two months is detected between the moments of heavy rains and the increase of water levels in the cavity. The CO2 content has a double periodicity, annual and daily

Modifications in host cell cytoskeleton structure and function mediated by intracellular HIV-1 Tat protein are greatly dependent on the second coding exon

Supplementary Data are available at NAR OnlineThe human immunodeficiency virus type 1 (HIV-1) regulator Tat is essential for viral replication because it achieves complete elongation of viral transcripts. Tat can be released to the extracellular space and taken up by adjacent cells, exerting profound cytoskeleton rearrangements that lead to apoptosis. In contrast, intracellular Tat has been described as protector from apoptosis. Tat gene is composed by two coding exons that yield a protein of 101 amino acids (aa). First exon (1–72aa) is sufficient for viral transcript elongation and second exon (73–101 aa) appears to contribute to non-transcriptional functions. We observed that Jurkat cells stably expressing intracellular Tat101 showed gene expression deregulation 4-fold higher than cells expressing Tat72. Functional experiments were performed to evaluate the effect of this deregulation. First, NF-iB-, NF-AT- and Sp1-dependent transcriptional activities were greatly enhanced in Jurkat-Tat101, whereas Tat72 induced milder but efficient activation. Second, cytoskeleton-related functions as cell morphology, proliferation, chemotaxis, polarization and actin polymerization were deeply altered in Jurkat- Tat101, but not in Jurkat-Tat72. Finally, expression of several cell surface receptors was dramatically impaired by intracellular Tat101 but not by Tat72. Consequently, these modifications were greatly dependent on Tat second exon and they could be related to the anergy observed in HIV-1-infected T cells.Plan Nacional del SIDA (MVI 1434/05–5), FIPSE 36584/ 06 and 36633/07, VIRHORST Network from Comunidad de Madrid (Spain), FIS PI040614 and PI0808752, ISCIII-RETIC RD06/0006, EUROPRISE Network of Excellence of the EU (Grant no. LSHP CT-2006- 037611), and BIO2008-04384 from the Ministerio de Ciencia e Innovacio´ n, Espan˜ a. Funding for open access charge: Instituto de Salud Carlos III, Ministry of Science and Technology, Spain.Peer reviewe

Cerebrovascular events and outcomes in hospitalized patients with COVID-19: The SVIN COVID-19 Multinational Registry

© 2020 World Stroke Organization.[Background]: Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has been associated with a significant risk of thrombotic events in critically ill patients. [Aim]: To summarize the findings of a multinational observational cohort of patients with SARS-CoV-2 and cerebrovascular disease. [Methods]: Retrospective observational cohort of consecutive adults evaluated in the emergency department and/or admitted with coronavirus disease 2019 (COVID-19) across 31 hospitals in four countries (1 February 2020–16 June 2020). The primary outcome was the incidence rate of cerebrovascular events, inclusive of acute ischemic stroke, intracranial hemorrhages (ICH), and cortical vein and/or sinus thrombosis (CVST). [Results]: Of the 14,483 patients with laboratory-confirmed SARS-CoV-2, 172 were diagnosed with an acute cerebrovascular event (1.13% of cohort; 1130/100,000 patients, 95%CI 970–1320/100,000), 68/171 (40.5%) were female and 96/172 (55.8%) were between the ages 60 and 79 years. Of these, 156 had acute ischemic stroke (1.08%; 1080/100,000 95%CI 920–1260/100,000), 28 ICH (0.19%; 190/100,000 95%CI 130–280/100,000), and 3 with CVST (0.02%; 20/100,000, 95%CI 4–60/100,000). The in-hospital mortality rate for SARS-CoV-2-associated stroke was 38.1% and for ICH 58.3%. After adjusting for clustering by site and age, baseline stroke severity, and all predictors of in-hospital mortality found in univariate regression (p < 0.1: male sex, tobacco use, arrival by emergency medical services, lower platelet and lymphocyte counts, and intracranial occlusion), cryptogenic stroke mechanism (aOR 5.01, 95%CI 1.63–15.44, p < 0.01), older age (aOR 1.78, 95%CI 1.07–2.94, p ¼ 0.03), and lower lymphocyte count on admission (aOR 0.58, 95%CI 0.34–0.98, p ¼ 0.04) were the only independent predictors of mortality among patients with stroke and COVID-19. [Conclusions]: COVID-19 is associated with a small but significant risk of clinically relevant cerebrovascular events, particularly ischemic stroke. The mortality rate is high for COVID-19-associated cerebrovascular complications; therefore, aggressive monitoring and early intervention should be pursued to mitigate poor outcomes

Optimizing sparse RFI prediction using deep learning

Radio frequency interference (RFI) is an ever-present limiting factor among radio telescopes even in the most remote observing locations. When looking to retain the maximum amount of sensitivity and reduce contamination for Epoch of Reionization studies, the identification and removal of RFI is especially important. In addition to improved RFI identification, we must also take into account computational efficiency of the RFI-Identification algorithm as radio interferometer arrays such as the Hydrogen Epoch of Reionization Array (HERA) grow larger in number of receivers. To address this, we present a deep fully convolutional neural network (DFCN) that is comprehensive in its use of interferometric data, where both amplitude and phase information are used jointly for identifying RFI. We train the network using simulated HERA visibilities containing mock RFI, yielding a known \u2018ground truth\u2019 data set for evaluating the accuracy of various RFI algorithms. Evaluation of the DFCN model is performed on observations from the 67 dish build-out, HERA-67, and achieves a data throughput of 1.6 7 105 HERA time-ordered 1024 channelled visibilities per hour per GPU. We determine that relative to an amplitude only network including visibility phase adds important adjacent time\u2013frequency context which increases discrimination between RFI and non-RFI. The inclusion of phase when predicting achieves a recall of 0.81, precision of 0.58, and F2 score of 0.75 as applied to our HERA-67 observations

A Real Time Processing system for big data in astronomy: Applications to HERA

As current- and next-generation astronomical instruments come online, they will generate an unprecedented deluge of data. Analyzing these data in real time presents unique conceptual and computational challenges, and their long-term storage and archiving is scientifically essential for generating reliable, reproducible results. We present here the real-time processing (RTP) system for the Hydrogen Epoch of Reionization Array (HERA), a radio interferometer endeavoring to provide the first detection of the highly redshifted 21 cm signal from Cosmic Dawn and the Epoch of Reionization by an interferometer. The RTP system consists of analysis routines run on raw data shortly after they are acquired, such as calibration and detection of radio-frequency interference (RFI) events. RTP works closely with the Librarian, the HERA data storage and transfer manager which automatically ingests data and transfers copies to other clusters for post-processing analysis. Both the RTP system and the Librarian are public and open source software, which allows for them to be modified for use in other scientific collaborations. When fully constructed, HERA is projected to generate over 50 terabytes (TB) of data each night, and the RTP system enables the successful scientific analysis of these data

Validation of the HERA Phase i Epoch of Reionization 21 cm Power Spectrum Software Pipeline

We describe the validation of the HERA Phase I software pipeline by a series of modular tests, building up to an end-to-end simulation. The philosophy of this approach is to validate the software and algorithms used in the Phase I upper-limit analysis on wholly synthetic data satisfying the assumptions of that analysis, not addressing whether the actual data meet these assumptions. We discuss the organization of this validation approach, the specific modular tests performed, and the construction of the end-to-end simulations. We explicitly discuss the limitations in scope of the current simulation effort. With mock visibility data generated from a known analytic power spectrum and a wide range of realistic instrumental effects and foregrounds, we demonstrate that the current pipeline produces power spectrum estimates that are consistent with known analytic inputs to within thermal noise levels (at the 2σ level) for k &gt; 0.2h Mpc-1 for both bands and fields considered. Our input spectrum is intentionally amplified to enable a strong "detection"at k ∼ 0.2 h Mpc-1 - at the level of ∼25σ - with foregrounds dominating on larger scales and thermal noise dominating at smaller scales. Our pipeline is able to detect this amplified input signal after suppressing foregrounds with a dynamic range (foreground to noise ratio) of ⪆107. Our validation test suite uncovered several sources of scale-independent signal loss throughout the pipeline, whose amplitude is well-characterized and accounted for in the final estimates. We conclude with a discussion of the steps required for the next round of data analysis

Methods of Error Estimation for Delay Power Spectra in 21 cm Cosmology

Precise measurements of the 21 cm power spectrum are crucial for understanding the physical processes of hydrogen reionization. Currently, this probe is being pursued by low-frequency radio interferometer arrays. As these experiments come closer to making a first detection of the signal, error estimation will play an increasingly important role in setting robust measurements. Using the delay power spectrum approach, we have produced a critical examination of different ways that one can estimate error bars on the power spectrum. We do this through a synthesis of analytic work, simulations of toy models, and tests on small amounts of real data. We find that, although computed independently, the different error bar methodologies are in good agreement with each other in the noise-dominated regime of the power spectrum. For our preferred methodology, the predicted probability distribution function is consistent with the empirical noise power distributions from both simulated and real data. This diagnosis is mainly in support of the forthcoming HERA upper limit and also is expected to be more generally applicable

First Results from HERA Phase I: Upper Limits on the Epoch of Reionization 21 cm Power Spectrum

We report upper limits on the Epoch of Reionization 21 cm power spectrum at redshifts 7.9 and 10.4 with 18 nights of data (∼36 hr of integration) from Phase I of the Hydrogen Epoch of Reionization Array (HERA). The Phase I data show evidence for systematics that can be largely suppressed with systematic models down to a dynamic range of ∼109 with respect to the peak foreground power. This yields a 95% confidence upper limit on the 21 cm power spectrum of 212≤(30.76)2mK2 at k = 0.192 h Mpc-1 at z = 7.9, and also 212≤(95.74)2mK2 at k = 0.256 h Mpc-1 at z = 10.4. At z = 7.9, these limits are the most sensitive to date by over an order of magnitude. While we find evidence for residual systematics at low line-of-sight Fourier k π modes, at high k π modes we find our data to be largely consistent with thermal noise, an indicator that the system could benefit from deeper integrations. The observed systematics could be due to radio frequency interference, cable subreflections, or residual instrumental cross-coupling, and warrant further study. This analysis emphasizes algorithms that have minimal inherent signal loss, although we do perform a careful accounting in a companion paper of the small forms of loss or bias associated with the pipeline. Overall, these results are a promising first step in the development of a tuned, instrument-specific analysis pipeline for HERA, particularly as Phase II construction is completed en route to reaching the full sensitivity of the experiment

Effects of model incompleteness on the drift-scan calibration of radio telescopes

Precision calibration poses challenges to experiments probing the redshifted 21-cm signal of neutral hydrogen from the Cosmic Dawn and Epoch of Reionization (z ∼30-6). In both interferometric and global signal experiments, systematic calibration is the leading source of error. Though many aspects of calibration have been studied, the overlap between the two types of instruments has received less attention. We investigate the sky based calibration of total power measurements with a HERA dish and an EDGES-style antenna to understand the role of autocorrelations in the calibration of an interferometer and the role of sky in calibrating a total power instrument. Using simulations we study various scenarios such as time variable gain, incomplete sky calibration model, and primary beam model. We find that temporal gain drifts, sky model incompleteness, and beam inaccuracies cause biases in the receiver gain amplitude and the receiver temperature estimates. In some cases, these biases mix spectral structure between beam and sky resulting in spectrally variable gain errors. Applying the calibration method to the HERA and EDGES data, we find good agreement with calibration via the more standard methods. Although instrumental gains are consistent with beam and sky errors similar in scale to those simulated, the receiver temperatures show significant deviations from expected values. While we show that it is possible to partially mitigate biases due to model inaccuracies by incorporating a time-dependent gain model in calibration, the resulting errors on calibration products are larger and more correlated. Completely addressing these biases will require more accurate sky and primary beam models