Keeping checkpoint/restart viable for exascale systems

Next-generation exascale systems, those capable of performing a quintillion operations per second, are expected to be delivered in the next 8-10 years. These systems, which will be 1,000 times faster than current systems, will be of unprecedented scale. As these systems continue to grow in size, faults will become increasingly common, even over the course of small calculations. Therefore, issues such as fault tolerance and reliability will limit application scalability. Current techniques to ensure progress across faults like checkpoint/restart, the dominant fault tolerance mechanism for the last 25 years, are increasingly problematic at the scales of future systems due to their excessive overheads. In this work, we evaluate a number of techniques to decrease the overhead of checkpoint/restart and keep this method viable for future exascale systems. More specifically, this work evaluates state-machine replication to dramatically increase the checkpoint interval (the time between successive checkpoints) and hash-based, probabilistic incremental checkpointing using graphics processing units to decrease the checkpoint commit time (the time to save one checkpoint). Using a combination of empirical analysis, modeling, and simulation, we study the costs and benefits of these approaches on a wide range of parameters. These results, which cover of number of high-performance computing capability workloads, different failure distributions, hardware mean time to failures, and I/O bandwidths, show the potential benefits of these techniques for meeting the reliability demands of future exascale platforms

Fault Location for Power Transmission Systems Using Magnetic Field Sensing Coils

The detection and location of faults on power transmission lines is essential to the protection and maintenance of a power system. Most methods of fault detection and location rely on measurements of electrical quantities provided by current and voltage transformers. These transformers can be expensive and require physical contact with the monitored high voltage equipment. In this work, current transformers were replaced by magnetic field sensing coils. Such coils can be located remotely from substations and switching stations and do not require physical contact with the conductors. Rather than observing each individual conductor, the use of the magnetic field sensors allows the monitoring of the transmission line condition using a collective quantity. This study explores the use of the magnetic field sensors as an alternative measurement device for fault detection and location

New data on the chronology of Pleistocene glaciation in the NW of the Iberian Peninsula

[Abstract] The age of glacial features subaerial exposition: polished surfaces and morainic blocks using cosmogenic isotopes in granite substrate areas of the NW Iberian Peninsula have permitted to distinguish several glacier phases in which until the moment was considered a single one attributed to the Würm. The resulting data are roughly consistent with the previous geomorphologic model for the area and improves the chronological accuracy and the understanding of the Pleistocene glacial dynamics in the NW Spain. The proposed sequence of events also fits very well with previous palaeoclimate reconstructions for the same period at world scale

Estimating GRACE terrestrial water storage anomaly using an improved point mass solution

The availability of terrestrial water storage anomaly (TWSA) data from the Gravity Recovery and Climate Experiment (GRACE) supports many hydrological applications. Five TWSA products are operational and publicly available, including three based on mass concentration (mascon) solutions and two based on the synthesis of spherical harmonic coefficients (SHCs). The mascon solutions have advantages regarding the synthesis of SHCs since the basis functions are represented locally rather than globally, which allows geophysical data constraints. Alternative new solutions based on SHCs are, therefore, critical and warranted to enrich the portfolio of user-friendly TWSA data based on different algorithms. TWSA data based on novel processing protocols is presented with a spatial re-sampling of 0.25 arc-degrees covering 2002–2022. This approach parameterizes the improved point mass (IPM) and adopts the synthesized residual gravitational potential as observations. The assay indicates that the proposed Hohai University (HHU-) IPM TWSA data reliably agree with the mascon solutions. The presented HHU-IPM TWSA data set would be instrumental in regional hydrological applications, particularly enabling improved assessment of regional water budgets

Hypoventilation in the PACU is associated with hypoventilation in the surgical ward: Post-hoc analysis of a randomized clinical trial

Objective: To evaluate the association between early postoperative hypoventilation in the last hour of the post -anesthesia care unit (PACU) stay and hypoventilation during the rest of the first 48 postoperative hours in the surgical ward. Design: Sub-analysis of a clinical trial. Setting: PACU and surgical wards of a single medical center. Patients: Adults having abdominal surgery under general anesthesia. Interventions: Monitoring with a respiratory volume monitor from admission to PACU until the earlier of 48 h after surgery or discharge. Measurements: The exposure was having at least one low minute-ventilation (MV) event during the last hour of PACU stay, defined as MV lower than 40% the predicted value lasting at least 1 min. The primary outcome was low MV events lasting at least 2 min during the rest of the first 48 postoperative hours, while in the surgical ward. The secondary outcome was the rate of low MV events per monitored hour. Main results: Data of 292 patients were analyzed, of which 20 (6.8%) patients had a low MV event in PACU. Low MV events in the surgical ward were found in 81 (28%) patients. All patients who had low MV events in PACU had events again in the ward, while 61/272 (22%) had an event in the ward but not in PACU. The incidence rate of low MV events per hour was 24 (95% CI: 13, 46) among patients having an event in the PACU, and 2 (1, 4) among those who did not. Conclusions: In adults recovering from abdominal surgery, events of hypoventilation during the first post-operative hour are associated with similar events during the rest of the first 48 postoperative hours, with positive predictive value approaching 100%. Sixty-one patients had ward hypoventilation that was not preceded by hypoventilation in PACU

Frenectomia labial pela técnica de reposicionamento cirúrgico proposta por Chelotti

O freio labial superior, localizado entre os incisivos centrais superiores, é uma estrutura anatômica fina e triangular com base voltada para apical e estendendo-se do tubérculo do lábio superior até o processo alveolar. Quando, ao se tracionar o lábio para frente, para baixo e lateralmente com o objetivo de manter o freio tenso, ocorre uma isquemia tecidual, a intervenção cirúrgica está indicada, obedecendo a princípios da necessidade e oportunidade cirúrgica, principalmente no paciente infantil. A proposta deste trabalho foi apresentar um caso clínico de paciente com oito anos de idade, gênero masculino, que apresentou ao exame clínico freio teto-labial persistente que, ao ser tracionado, produzia isquemia na papila palatina, além da presença de diastema interincisal. O tratamento proposto foi o reposicionamento cirúrgico do freio. Concluiu-se que a técnica proposta contribuiu para o fechamento espontâneo do diastema e preservou as características anatômicas, funcionais e estéticas do freio labial superior.

Differences in pregnancy metabolic profiles and their determinants between White European and South Asian women:Findings from the Born in Bradford Cohort

There is widespread metabolic disruption in women upon becoming pregnant. South Asians (SA) compared to White Europeans (WE) have more fat mass and are more insulin-resistant at a given body mass index (BMI). Whether these are reflected in other gestational metabolomic differences is unclear. Our aim was to compare gestational metabolic profiles and their determinants between WE and SA women. We used data from a United Kingdom (UK) cohort to compare metabolic profiles and associations of maternal age, education, parity, height, BMI, tricep skinfold thickness, gestational diabetes (GD), pre-eclampsia, and gestational hypertension with 156 metabolic measurements in WE (n = 4072) and SA (n = 4702) women. Metabolic profiles, measured in fasting serum taken between 26–28 weeks gestation, were quantified by nuclear magnetic resonance. Distributions of most metabolic measures differed by ethnicity. WE women had higher levels of most lipoprotein subclasses, cholesterol, glycerides and phospholipids, monosaturated fatty acids, and creatinine but lower levels of glucose, linoleic acid, omega-6 and polyunsaturated fatty acids, and most amino acids. Higher BMI and having GD were associated with higher levels of several lipoprotein subclasses, triglycerides, and other metabolites, mostly with stronger associations in WEs. We have shown differences in gestational metabolic profiles between WE and SA women and demonstrated that associations of exposures with these metabolites differ by ethnicity

MeerKLASS: MeerKAT Large Area Synoptic Survey

We discuss the ground-breaking science that will be possible with a wide area survey, using the MeerKAT telescope, known as MeerKLASS (MeerKAT Large Area Synoptic Survey). The current specifications of MeerKAT make it a great fit for science applications that require large survey speeds but not necessarily high angular resolutions. In particular, for cosmology, a large survey over $\sim 4,000 \, {\rm deg}^2$ for $\sim 4,000$ hours will potentially provide the first ever measurements of the baryon acoustic oscillations using the 21cm intensity mapping technique, with enough accuracy to impose constraints on the nature of dark energy. The combination with multi-wavelength data will give unique additional information, such as exquisite constraints on primordial non-Gaussianity using the multi-tracer technique, as well as a better handle on foregrounds and systematics. Such a wide survey with MeerKAT is also a great match for HI galaxy studies, providing unrivalled statistics in the pre-SKA era for galaxies resolved in the HI emission line beyond local structures at z > 0.01. It will also produce a large continuum galaxy sample down to a depth of about 5\,$\mu$Jy in L-band, which is quite unique over such large areas and will allow studies of the large-scale structure of the Universe out to high redshifts, complementing the galaxy HI survey to form a transformational multi-wavelength approach to study galaxy dynamics and evolution. Finally, the same survey will supply unique information for a range of other science applications, including a large statistical investigation of galaxy clusters as well as produce a rotation measure map across a huge swathe of the sky. The MeerKLASS survey will be a crucial step on the road to using SKA1-MID for cosmological applications and other commensal surveys, as described in the top priority SKA key science projects (abridged).Comment: Larger version of the paper submitted to the Proceedings of Science, "MeerKAT Science: On the Pathway to the SKA", Stellenbosch, 25-27 May 201

Skipping breakfast is associated with adiposity markers especially when sleep time is adequate in adolescents

Adolescence is a critical stage of development and has an important influence on energy balancerelated behaviours (EBRBs). When adolescents are associated with obesity it can lead to increased cardiometabolic risk. Here we assess if EBRBs adopted by adolescents included in a subsample are associated with markers of total and abdominal adiposity in a multicentre European study, Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA-CSS) and a Brazilian study, Brazilian Cardiovascular Adolescent Health (BRACAH study), and whether sleep duration influence the association between skipping breakfast, physical activity and sedentary behaviours, with total and abdominal obesity (AO). Multilevel linear regression models using fixed and random intercepts were used to analyse the association between markers of obesity and EBRBs. Skipping breakfast was the prevalent behaviour in association with obesity among European and Brazilian boys besides European girls, even after stratification by sleep time. Moreover, European boys who slept properly and skipped breakfast had an increased waist circumference (WC), while body mass index (BMI) increased in Brazilian boys. Among Brazilian boys less sleep was protective for total obesity (β = −0.93 kg/m2; 95% CI: −1.80; −0.07). European girls when they were more sedentary, showed an increase in WC, especially for those who reported they slept adequately. Skipping breakfast was associated with total and AO in adolescents independent of sleep duration.The HELENA-CSS took place with the financial support of the European Community Sixth RTD Framework Program (contract FOOD-CT-2005-007034). This study was also supported by a grant from the Spanish Ministry of Health: Maternal, Child Health and Development Network (numberRD08/0072) and grants from the Spanish Ministry of Education (EX-2008-0641) and the Swedish Heart-Lung Foundation (20090635). And supported by grants from the Spanish Ministry of Science and Innovation (JCI-2010-07055 and RYC-2010-05957). The authors thanked for the contribution of the HELENA Study Group. We are grateful for the financial support to the authors: Dr. Elsie C. O. Forkert was given a post-doctoral schoolarship from the Sao Paulo Research Foundation FAPESP (proc.2018/02887-6). Dr. Augusto César F. De Moraes was given a post-doctoral scholarship from the National Council for Scientific and Technological Development (CNPq: proc. 313772/2014-2) and the São Paulo Research Foundation FAPESP (proc. 2014/13367-2 and 2015/14319-4). Full Prof. Luis A. Moreno was given a scholarship of a visiting professor from São Paulo Research Foundation FAPESP (proc. 2015/11406-3). Dr Prof Heráclito B Carvalho is in receipt of an advanced scientist scholarship from the National Council for Scientific and Technological Development (CNPq: proc. 300951/2015-9)