scholarly journals A Bayesian data assimilation framework for lake 3D hydrodynamic models with a physics-preserving particle filtering method using SPUX-MITgcm v1

2021 ◽  
Author(s):  
Artur Safin ◽  
Damien Bouffard ◽  
Firat Ozdemir ◽  
Cintia L. Ramón ◽  
James Runnalls ◽  
...  

Abstract. We present a Bayesian inference for a three-dimensional hydrodynamic model of Lake Geneva with stochastic weather forcing and high-frequency observational datasets. This is achieved by coupling a Bayesian inference package, SPUX, with a hydrodynamics package, MITgcm, into a single framework, SPUX-MITgcm. To mitigate uncertainty in the atmospheric forcing, we use a smoothed particle Markov chain Monte Carlo method, where the intermediate model state posteriors are resampled in accordance with their respective observational likelihoods. To improve the assimilation of remotely sensed temperature, we develop a bi-directional Long Short-Term Memory (Bi-LSTM) neural network to estimate lake skin temperature from a history of hydrodynamic bulk temperature predictions and atmospheric data. This study analyzes the benefit and costs of such state of the art computationally expensive calibration and assimilation method for lakes.

2018 ◽  
Vol 13 (2) ◽  
pp. 187-211
Author(s):  
Patricia E. Chu

The Paris avant-garde milieu from which both Cirque Calder/Calder's Circus and Painlevé’s early films emerged was a cultural intersection of art and the twentieth-century life sciences. In turning to the style of current scientific journals, the Paris surrealists can be understood as engaging the (life) sciences not simply as a provider of normative categories of materiality to be dismissed, but as a companion in apprehending the “reality” of a world beneath the surface just as real as the one visible to the naked eye. I will focus in this essay on two modernist practices in new media in the context of the history of the life sciences: Jean Painlevé’s (1902–1989) science films and Alexander Calder's (1898–1976) work in three-dimensional moving art and performance—the Circus. In analyzing Painlevé’s work, I discuss it as exemplary of a moment when life sciences and avant-garde technical methods and philosophies created each other rather than being classified as separate categories of epistemological work. In moving from Painlevé’s films to Alexander Calder's Circus, Painlevé’s cinematography remains at the forefront; I use his film of one of Calder's performances of the Circus, a collaboration the men had taken two decades to complete. Painlevé’s depiction allows us to see the elements of Calder's work that mark it as akin to Painlevé’s own interest in a modern experimental organicism as central to the so-called machine-age. Calder's work can be understood as similarly developing an avant-garde practice along the line between the bestiary of the natural historian and the bestiary of the modern life scientist.


Author(s):  
Hongzhang Zhu ◽  
Shi-Ting Feng ◽  
Xingqi Zhang ◽  
Zunfu Ke ◽  
Ruixi Zeng ◽  
...  

Background: Cutis Verticis Gyrata (CVG) is a rare skin disease caused by overgrowth of the scalp, presenting as cerebriform folds and wrinkles. CVG can be classified into two forms: primary (essential and non-essential) and secondary. The primary non-essential form is often associated with neurological and ophthalmological abnormalities, while the primary essential form occurs without associated comorbidities. Discussion: We report on a rare case of primary essential CVG with a 4-year history of normal-colored scalp skin mass in the parietal-occipital region without symptom in a 34-year-old male patient, retrospectively summarizing his pathological and Computer Tomography (CT) and magnetic resonance imaging (MRI) findings. The major clinical observations on the CT and MR sectional images include a thickened dermis and excessive growth of the scalp, forming the characteristic scalp folds. With the help of CT and MRI Three-dimensional (3D) reconstruction techniques, the characteristic skin changes could be displayed intuitively, providing more evidence for a diagnosis of CVG. At the 5-year followup, there were no obvious changes in the lesion. Conclusion: Based on our observations, we propose that not all patients with primary essential CVG need surgical intervention, and continuous clinical observation should be an appropriate therapy for those in stable condition.


2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Asiyeh Shojaee ◽  
Firooze Ronnasian ◽  
Mahdiyeh Behnam ◽  
Mansoor Salehi

AbstractBackgroundSirenomelia, also called mermaid syndrome, is a rare lethal multi-system congenital deformity with an incidence of one in 60,000–70,000 pregnancies. Sirenomelia is mainly characterized by the fusion of lower limbs and is widely associated with severe urogenital and gastrointestinal malformations. The presence of a single umbilical artery derived from the vitelline artery is the main anatomical feature distinguishing sirenomelia from caudal regression syndrome. First-trimester diagnosis of this disorder and induced abortion may be the safest medical option. In this report, two cases of sirenomelia that occurred in an white family will be discussed.Case presentationWe report two white cases of sirenomelia occurring in a 31-year-old multigravid pregnant woman. In the first pregnancy (18 weeks of gestation) abortion was performed, but in the third pregnancy (32 weeks) the stillborn baby was delivered by spontaneous vaginal birth. In the second and fourth pregnancies, however, she gave birth to normal babies. Three-dimensional ultrasound imaging showed fusion of the lower limbs. Neither she nor any member of her family had a history of diabetes. In terms of other risk factors, she had no history of exposure to teratogenic agents during her pregnancy. Also, her marriage was non-consanguineous.ConclusionThis report suggests the existence of a genetic background in this mother with a Mendelian inheritance pattern of 50% second-generation incidence in her offspring.


2021 ◽  
Vol 13 (9) ◽  
pp. 4905
Author(s):  
Chen Cao ◽  
Xiangbin Wu ◽  
Lizhi Yang ◽  
Qian Zhang ◽  
Xianying Wang ◽  
...  

Exploring the spatiotemporal distribution of earthquake activity, especially earthquake migration of fault systems, can greatly to understand the basic mechanics of earthquakes and the assessment of earthquake risk. By establishing a three-dimensional strike-slip fault model, to derive the stress response and fault slip along the fault under regional stress conditions. Our study helps to create a long-term, complete earthquake catalog. We modelled Long-Short Term Memory (LSTM) networks for pattern recognition of the synthetical earthquake catalog. The performance of the models was compared using the mean-square error (MSE). Our results showed clearly the application of LSTM showed a meaningful result of 0.08% in the MSE values. Our best model can predict the time and magnitude of the earthquakes with a magnitude greater than Mw = 6.5 with a similar clustering period. These results showed conclusively that applying LSTM in a spatiotemporal series prediction provides a potential application in the study of earthquake mechanics and forecasting of major earthquake events.


Author(s):  
Lu Gao ◽  
Yao Yu ◽  
Yi Hao Ren ◽  
Pan Lu

Pavement maintenance and rehabilitation (M&R) records are important as they provide documentation that M&R treatment is being performed and completed appropriately. Moreover, the development of pavement performance models relies heavily on the quality of the condition data collected and on the M&R records. However, the history of pavement M&R activities is often missing or unavailable to highway agencies for many reasons. Without accurate M&R records, it is difficult to determine if a condition change between two consecutive inspections is the result of M&R intervention, deterioration, or measurement errors. In this paper, we employed deep-learning networks of a convolutional neural network (CNN) model, a long short-term memory (LSTM) model, and a CNN-LSTM combination model to automatically detect if an M&R treatment was applied to a pavement section during a given time period. Unlike conventional analysis methods so far followed, deep-learning techniques do not require any feature extraction. The maximum accuracy obtained for test data is 87.5% using CNN-LSTM.


2021 ◽  
Vol 503 (3) ◽  
pp. 3309-3325
Author(s):  
Sabine Bellstedt ◽  
Aaron S G Robotham ◽  
Simon P Driver ◽  
Jessica E Thorne ◽  
Luke J M Davies ◽  
...  

ABSTRACT We analyse the metallicity histories of ∼4500 galaxies from the GAMA survey at z < 0.06 modelled by the SED-fitting code ProSpect using an evolving metallicity implementation. These metallicity histories, in combination with the associated star formation histories, allow us to analyse the inferred gas-phase mass–metallicity relation. Furthermore, we extract the mass–metallicity relation at a sequence of epochs in cosmic history, to track the evolving mass–metallicity relation with time. Through comparison with observations of gas-phase metallicity over a large range of redshifts, we show that, remarkably, our forensic SED analysis has produced an evolving mass–metallicity relationship that is consistent with observations at all epochs. We additionally analyse the three-dimensional mass–metallicity–SFR space, showing that galaxies occupy a clearly defined plane. This plane is shown to be subtly evolving, displaying an increased tilt with time caused by general enrichment, and also the slowing down of star formation with cosmic time. This evolution is most apparent at lookback times greater than 7 Gyr. The trends in metallicity recovered in this work highlight that the evolving metallicity implementation used within the SED-fitting code ProSpect produces reasonable metallicity results over the history of a galaxy. This is expected to provide a significant improvement to the accuracy of the SED-fitting outputs.


2020 ◽  
Vol 36 (Supplement_2) ◽  
pp. i675-i683
Author(s):  
Sudhir Kumar ◽  
Antonia Chroni ◽  
Koichiro Tamura ◽  
Maxwell Sanderford ◽  
Olumide Oladeinde ◽  
...  

Abstract Summary Metastases cause a vast majority of cancer morbidity and mortality. Metastatic clones are formed by dispersal of cancer cells to secondary tissues, and are not medically detected or visible until later stages of cancer development. Clone phylogenies within patients provide a means of tracing the otherwise inaccessible dynamic history of migrations of cancer cells. Here, we present a new Bayesian approach, PathFinder, for reconstructing the routes of cancer cell migrations. PathFinder uses the clone phylogeny, the number of mutational differences among clones, and the information on the presence and absence of observed clones in primary and metastatic tumors. By analyzing simulated datasets, we found that PathFinder performes well in reconstructing clone migrations from the primary tumor to new metastases as well as between metastases. It was more challenging to trace migrations from metastases back to primary tumors. We found that a vast majority of errors can be corrected by sampling more clones per tumor, and by increasing the number of genetic variants assayed per clone. We also identified situations in which phylogenetic approaches alone are not sufficient to reconstruct migration routes. In conclusion, we anticipate that the use of PathFinder will enable a more reliable inference of migration histories and their posterior probabilities, which is required to assess the relative preponderance of seeding of new metastasis by clones from primary tumors and/or existing metastases. Availability and implementation PathFinder is available on the web at https://github.com/SayakaMiura/PathFinder.


2020 ◽  
Vol 17 (1) ◽  
pp. 67-75
Author(s):  
John Fry ◽  
Oliver Smart ◽  
Jean-Philippe Serbera ◽  
Bernhard Klar

Abstract Amid much recent interest we discuss a Variance Gamma model for Rugby Union matches (applications to other sports are possible). Our model emerges as a special case of the recently introduced Gamma Difference distribution though there is a rich history of applied work using the Variance Gamma distribution – particularly in finance. Restricting to this special case adds analytical tractability and computational ease. Our three-dimensional model extends classical two-dimensional Poisson models for soccer. Analytical results are obtained for match outcomes, total score and the awarding of bonus points. Model calibration is demonstrated using historical results, bookmakers’ data and tournament simulations.


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