The Order/Radix Problem (ORP) is an optimization problem that can be solved to find an optimal network topology in distributed memory systems. It is important to find the optimum number of switches ...in the ORP. In the case of a regular graph, a good estimation of the preferred number of switches has been proposed, and it has been shown that simulated annealing (SA) finds a good solution given a fixed number of switches. However, generally the optimal graph does not necessarily satisfy the regular condition, which greatly increases the computational costs required to find a good solution with a suitable number of switches for each case. This study improved the new method based on SA to find a suitable number of switches. By introducing neighborhood searches in which the number of switches is increased or decreased, our method can optimize a graph by changing the number of switches adaptively during the search. In numerical experiments, we verified that our method shows a good approximation for the best setting for the number of switches, and can simultaneously generate a graph with a small host-to-host average shortest path length, using instances presented by Graph Golf, an international ORP competition.
It is known that an indirect network with a small host-to-host Average Shortest Path Length (h-ASPL) improves overall system performance in a parallel computer system. As a means to discuss such ...indirect networks in graph theory, the Order/Radix Problem (ORP) has been proposed. ORP involves finding a graph with a minimum h-ASPL that satisfies a given number of hosts and radix. A graph in ORP represents an indirect network and has two types of vertices: host and switch. We propose an optimization algorithm to generate graphs with a sufficiently small h-ASPL. The primary features of the proposed algorithm are the symmetry of the graph and the bias of the hosts adjacent to each switch. These features reduce the computational time to calculate the h-ASPL and improve the search performance of the algorithm. The performance of the proposed algorithm is evaluated using problems presented by Graph Golf, an international ORP competition. Our results show that the proposed algorithm can generate graphs with a smaller h-ASPL than the existing algorithm. To evaluate the performance of the graphs generated by the proposed algorithm, we use the parallel simulation framework SimGrid and the parallel benchmark collection NAS Parallel Benchmarks. Our results also show that the graphs generated by the proposed algorithm have higher performance than those generated by the existing algorithm.
In various industrial products including parallel computing systems, it is expected that the performance of the whole system will be improved by applying a network topology with smaller diameter and ...average shortest path length (ASPL). Such network topologies can be defined as the order/degree problem in graph theory by modeling a network topology as an undirected graph. Although previous research indicates that the random graph has both small diameter and ASPL due to the small-world effect, there is still room for improvement. In this paper, we propose an algorithm for the order/degree problem that optimizes random graphs. The feature of the proposed algorithm is that by giving symmetry to the graph, the solution search performance is improved and the calculation time for obtaining the diameter and APSL is greatly reduced. The proposed algorithm is evaluated using various graphs, including a huge graph with one million vertices presented by Graph Golf, an international competition for the order/degree problem. The results show that the proposed algorithm can generate a network topology with sufficiently small diameter and APSL. In addition, we also simulate the latency, performance of the parallel benchmarks, and bisection on the generated network topologies. The results show that the generated network topology performs better than the random topology and a conventional k-ary n-cube topology.
It is crucial to interpret fetal heart rate patterns with a focus on the pattern evolution during labor to estimate the relationship between cerebral palsy and delivery. However, nationwide data are ...not available.
The aim of our study was to demonstrate the features of fetal heart rate pattern evolution and estimate the timing of fetal brain injury during labor in cerebral palsy cases.
In this longitudinal study, 1069 consecutive intrapartum fetal heart rate strips from infants with severe cerebral palsy at or beyond 34 weeks of gestation, were analyzed. They were categorized as follows: (1) continuous bradycardia (Bradycardia), (2) persistently nonreassuring, (3) reassuring-prolonged deceleration, (4) Hon’s pattern, and (5) persistently reassuring. The clinical factors underlying cerebral palsy in each group were assessed.
Hypoxic brain injury during labor (those in the reassuring-prolonged deceleration and Hon’s pattern groups) accounted for 31.5% of severe cerebral palsy cases and at least 30% of those developed during the antenatal period. Of the 1069 cases, 7.86% were classified as continuous bradycardia (n=84), 21.7% as persistently nonreassuring (n=232), 15.6% as reassuring-prolonged deceleration (n=167), 15.9% as Hon’s pattern (n=170), 19.8% as persistently reassuring (n=212), and 19.1% were unclassified (n=204). The overall interobserver agreement was moderate (kappa 0.59). Placental abruption was the most common cause (31.9%) of cerebral palsy, accounting for almost 90% of cases in the continuous bradycardia group (64 of 73). Among the cases in the Hon’s pattern group (n=67), umbilical cord abnormalities were the most common clinical factor for cerebral palsy development (29.9%), followed by placental abruption (20.9%), and inappropriate operative vaginal delivery (13.4%).
Intrapartum hypoxic brain injury accounted for approximately 30% of severe cerebral palsy cases, whereas a substantial proportion of the cases were suspected to have either a prenatal or postnatal onset. Up to 16% of cerebral palsy cases may be preventable by placing a greater focus on the earlier changes seen in the Hon’s fetal heart rate progression.
Objective
To investigate the association between hypoxic‐ischaemic insult timing and brain injury type in infants with severe cerebral palsy (CP).
Design
Longitudinal study.
Setting
Database of the ...Recurrence Prevention Committee, Japan Obstetric Compensation System for Cerebral Palsy.
Sample
Infants with severe CP born at ≥34 weeks of gestation.
Methods
The intrapartum fetal heart rate (FHR) strips were categorised as continuous bradycardia; persistently non‐reassuring (NR‐NR); reassuring‐prolonged deceleration (R‐PD); Hon's pattern (R‐Hon); persistently reassuring (R‐R); and unclassified. The brain magnetic resonance imaging (MRI) scans were categorised based on the predominant site involved: basal ganglia‐thalamus (BGT); white matter (WM); watershed (WS); stroke; normal; and unclassified.
Main outcome measures
Manifestations of the brain MRI types and the association between FHR evolution pattern and MRI type were analysed.
Results
Among 672 eligible infants, 76% had BGT‐dominant injury, 5.4% WM, 1.2% WS, 1.6% stroke, 1.9% normal, and 14% unclassified. Placental abruption and small‐for‐gestational age were associated with an increased (adjusted odds ratio aOR 8.02) and decreased (aOR 0.38) risk of BGT injury, respectively. The majority of infants had BGT injury in most FHR groups (bradycardia, 97%; NR‐NR, 75%; R‐PD, 90%; R‐Hon, 76%; and R‐R, 45%). The risk profiles in case of BGT in the NR‐NR group were similar to those in the R‐PD and R‐Hon groups.
Conclusion
BGT‐dominant brain damage accounted for three‐fourths of the cases of CP in term or near‐term infants, even in prenatal onset cases. Hypoxic‐ischaemic insult has a major impact on CP development during the antenatal period.
Tweetable
Basal ganglia‐thalamus injury constitutes 76% of severe cerebral palsy cases, predominant even in antenatal‐onset cases.
Tweetable
Basal ganglia‐thalamus injury constitutes 76% of severe cerebral palsy cases, predominant even in antenatal‐onset cases.
This article includes Author Insights, a video available at https://vimeo.com/bjogs/authorinsights17089.
Shift workers have been reported to have an increased risk of some cancers. However, the risk of prostate cancer in shift workers is not known to have been examined previously. This study ...prospectively examined the association between shift work and risk of prostate cancer incidence among 14,052 working men in Japan enrolled in a large-scale prospective cohort. A baseline survey was conducted between 1988 and 1990. Subjects were asked to indicate the most regular work schedule they had undertaken previously: day work, rotating-shift work, or fixed-night work. During 111,974 person-years, 31 cases of prostate cancer were recorded. The Cox proportional hazards model was used to estimate the risk, with adjustments for age, family history of prostate cancer, study area surveyed, body mass index, smoking, alcohol drinking, job type, physical activity at work, workplace, perceived stress, educational level, and marriage status. Compared with day workers, rotating-shift workers were significantly at risk for prostate cancer (relative risk = 3.0, 95% confidence interval: 1.2, 7.7), whereas fixed-night work was associated with a small and nonsignificant increase in risk. This report is the first known to reveal a significant relation between rotating-shift work and prostate cancer.
To improve productivity for developing parallel applications on high performance computing systems, the XcalableMP PGAS language has been proposed. XcalableMP supports both a typical parallelization ...under the “global-view memory model” which uses directives and a flexible parallelization under the “local-view memory model” which uses coarray features. The goal of the present paper is to clarify XcalableMP’s productivity and performance. To do so, we implement and evaluate the high performance computing challenge benchmark, namely, EP STREAM Triad, High Performance Linpack, Global fast Fourier transform, and RandomAccess on the K computer using up to 16,384 compute nodes and a generic cluster system using up to 128 compute nodes. We found that we could more easily implement the benchmarks using XcalableMP rather than using MPI. Moreover, most of the performance results using XcalableMP were almost the same as those using MPI.
Abstract The prenatal diagnosis of fetal heart disease potentially influences parental decision-making regarding pregnancy termination. Existing literature indicates that the severity, whether in ...complexity or lethality, significantly influences parental decisions concerning abortion. However, questions remain as to how fetal heart disease severity impacts parental decisions, given recent advancements in postsurgical outcomes. Therefore, we investigated risk factors associated with parents’ decision-making regarding abortion following a prenatal diagnosis of fetal heart disease. Our analysis included 73 (terminated: n = 37; continued: n = 36) pregnancies with a fetal heart disease diagnosed before 22 weeks of gestation. Increased gestational age at diagnosis reduced the likelihood of parents’ decision on termination (Model 1: adjusted odds ratio, 0.94; 95% confidence interval 0.89–0.99; Model 2: 0.95 0.90–0.997). Critical disease (5.25; 1.09–25.19) and concurrent extracardiac or genetic abnormalities (Model 1: 4.19, 1.21–14.53; Model 2: 5.47, 1.50–19.96) increased the likelihood of choosing abortion. Notably, complex disease did not significantly influence parental decisions (0.56; 0.14–2.20). These results suggest that parental decision-making regarding abortion may be influenced by earlier gestational age at diagnosis, the lethality of heart disease, and extracardiac or genetic abnormalities, but not its complexity if prenatal diagnosis and parental counseling are provided at a cardiovascular-specialized facility.
There is increasing demand for the high-speed processing of large-scale graphs in various fields. However, such graph processing requires irregular calculations, making it difficult to scale ...performance on large-scale distributed memory systems. Against this background, Graph500, a competition for evaluating the performance of large-scale graph processing, has been held. We developed breadth-first search (BFS), which is one of the benchmark kernels used in Graph500, and took the top spot a total of 10 times using the K computer. In this paper, we tune BFS performance and evaluate it using the supercomputer Fugaku, which is the successor to the K computer. The results of evaluating BFS for a large-scale graph composed of about 1.1 trillion vertices and 17.6 trillion edges using 92,160 nodes of Fugaku indicate that Fugaku has 2.27 times the performance of the K computer. Fugaku took the top spot on Graph500 in June 2020.
The aim of the present study was to clarify fetal heart rate (FHR) evolution patterns in infants with cerebral palsy (CP) according to different types of umbilical cord complications.
This ...case-control study included children born: with a birth weight ≥2000 g, at gestational age ≥33 weeks, with disability due to CP, and between 2009 and 2014. Obstetric characteristics and FHR patterns were compared among patients with CP associated with (126 cases) and without (594 controls) umbilical cord complications.
There were 32 umbilical cord prolapse cases and 94 cases with coexistent antenatal umbilical cord complications. Compared with the control group, the persistent non-reassuring pattern was more frequent in cases with coexistent antenatal umbilical cord complications (p = 0.012). A reassuring FHR pattern was observed on admission, but resulted in prolonged deceleration, especially during the first stage of labor, and was significantly identified in 69% of cases with umbilical cord prolapse and 35% of cases with antenatal cord complications, compared to 17% of control cases (p < 0.001).
Hypercoiled cord and abnormal placental umbilical cord insertion, may be associated with CP due to acute hypoxic-ischemic injury as well as sub-acute or chronic adverse events during pregnancy, while umbilical cord prolapse may be characterized by acute hypoxic-ischemic injury during delivery.