Miracle-dz/UniFAR-FTUs huggingface dataset:
Minimax Regret for Stochastic Shortest Path

We study the Stochastic Shortest Path (SSP) problem in which an agent has to reach a goal state in minimum total expected cost. In the learning formulation of the problem, the agent has no prior knowledge about the costs and dynamics of the model. She repeatedly interacts with the model for $K$ episodes, and has to minimize her regret. In this work we show that the minimax regret for this setting is $\widetilde O(\sqrt{ (B_\star^2 + B_\star) |S| |A| K})$ where $B_\star$ is a bound on the expected cost of the optimal policy from any state, $S$ is the state space, and $A$ is the action space. This matches the $\Omega (\sqrt{ B_\star^2 |S| |A| K})$ lower bound of Rosenberg et al. [2020] for $B_\star \ge 1$, and improves their regret bound by a factor of $\sqrt{|S|}$. For $B_\star<1$ we prove a matching lower bound of $\Omega (\sqrt{ B_\star |S| |A| K})$. Our algorithm is based on a novel reduction from SSP to finite-horizon MDPs. To that end, we provide an algorithm for the finite-horizon setting whose leading term in the regret depends polynomially on the expected cost of the optimal policy and only logarithmically on the horizon.
Volumetric Propagation Network: Stereo-LiDAR Fusion for Long-Range Depth Estimation

Stereo-LiDAR fusion is a promising task in that we can utilize two different types of 3D perceptions for practical usage – dense 3D information (stereo cameras) and highly-accurate sparse point clouds (LiDAR). However, due to their different modalities and structures, the method of aligning sensor data is the key for successful sensor fusion. To this end, we propose a geometry-aware stereo-LiDAR fusion network for long-range depth estimation, called volumetric propagation network. The key idea of our network is to exploit sparse and accurate point clouds as a cue for guiding correspondences of stereo images in a unified 3D volume space. Unlike existing fusion strategies, we directly embed point clouds into the volume, which enables us to propagate valid information into nearby voxels in the volume, and to reduce the uncertainty of correspondences. Thus, it allows us to fuse two different input modalities seamlessly and regress a long-range depth map. Our fusion is further enhanced by a newly proposed feature extraction layer for point clouds guided by images: FusionConv. FusionConv extracts point cloud features that consider both semantic (2D image domain) and geometric (3D domain) relations and aid fusion at the volume. Our network achieves state-of-the-art performance on KITTI and Virtual-KITTI datasets among recent stereo-LiDAR fusion methods.
The Gradient Convergence Bound of Federated Multi-Agent Reinforcement Learning With Efficient Communication

The paper considers independent reinforcement learning (IRL) for multi-agent collaborative decision-making in the paradigm of federated learning (FL). However, FL generates excessive communication overheads between agents and a remote central server, especially when it involves a large number of agents or iterations. Besides, due to the heterogeneity of independent learning environments, multiple agents may undergo asynchronous Markov decision processes (MDPs), which will affect the training samples and the model’s convergence performance. On top of the variation-aware periodic averaging (VPA) method and the policy-based deep reinforcement learning (DRL) algorithm (i.e., proximal policy optimization (PPO)), this paper proposes two advanced optimization schemes orienting to stochastic gradient descent (SGD): 1) A decay-based scheme gradually decays the weights of a model’s local gradients with the progress of successive local updates, and 2) By representing the agents as a graph, a consensus-based scheme studies the impact of exchanging a model’s local gradients among nearby agents from an algebraic connectivity perspective. This paper also provides novel convergence guarantees for both developed schemes, and demonstrates their superior effectiveness and efficiency in improving the system’s utility value through theoretical analyses and simulation results.
X-View: Non-Egocentric Multi-View 3D Object Detector

3D object detection algorithms for autonomous driving reason about 3D obstacles either from 3D birds-eye view or perspective view or both. Recent works attempt to improve the detection performance via mining and fusing from multiple egocentric views. Although the egocentric perspective view alleviates some weaknesses of the birds-eye view, the sectored grid partition becomes so coarse in the distance that the targets and surrounding context mix together, which makes the features less discriminative. In this paper, we generalize the research on 3D multi-view learning and propose a novel multi-view-based 3D detection method, named X-view, to overcome the drawbacks of the multi-view methods. Specifically, X-view breaks through the traditional limitation about the perspective view whose original point must be consistent with the 3D Cartesian coordinate. X-view is designed as a general paradigm that can be applied on almost any 3D detectors based on LiDAR with only little increment of running time, no matter it is voxel/grid-based or raw-point-based. We conduct experiments on KITTI and NuScenes datasets to demonstrate the robustness and effectiveness of our proposed X-view. The results show that X-view obtains consistent improvements when combined with mainstream state-of-the-art 3D methods.
Advances in space quantum communications

Concerted efforts are underway to establish an infrastructure for a global quantum internet to realise a spectrum of quantum technologies. This will enable more precise sensors, secure communications, and faster data processing. Quantum communications are a front-runner with quantum networks already implemented in several metropolitan areas. A number of recent proposals have modelled the use of space segments to overcome range limitations of purely terrestrial networks. Rapid progress in the design of quantum devices have enabled their deployment in space for in-orbit demonstrations. We review developments in this emerging area of space-based quantum technologies and provide a roadmap of key milestones towards a complete, global quantum networked landscape. Small satellites hold increasing promise to provide a cost effective coverage required to realised the quantum internet. We review the state of art in small satellite missions and collate the most current in-field demonstrations of quantum cryptography. We summarise important challenges in space quantum technologies that must be overcome and recent efforts to mitigate their effects. A perspective on future developments that would improve the performance of space quantum communications is included. We conclude with a discussion on fundamental physics experiments that could take advantage of a global, space-based quantum network.
Reconstruction from smaller cards

The $\ell$-deck of a graph $G$ is the multiset of all induced subgraphs of $G$ on $\ell$ vertices. We say that a graph is reconstructible from its $\ell$-deck if no other graph has the same $\ell$-deck. In 1957, Kelly showed that every tree with $n\ge3$ vertices can be reconstructed from its $(n-1)$-deck, and Giles strengthened this in 1976, proving that trees on at least 6 vertices can be reconstructed from their $(n-2)$-decks. Our main theorem states that trees are reconstructible from their $(n-r)$-decks for all $r\le n/{9}+o(n)$, making substantial progress towards a conjecture of N\'ydl from 1990. In addition, we can recognise the connectedness of a graph from its $\ell$-deck when $\ell\ge 9n/10$, and reconstruct the degree sequence when $\ell\ge\sqrt{2n\log(2n)}$. All of these results are significant improvements on previous bounds.
The Mechanical Properties of Thin Anodic Films on Aluminum

The measured stresses associated with the growth of oxide on the surface of aluminum are much lower than those calculated from the Pilling‐Bedworth ratio. The magnitude of the stresses in alumina formed anodically on pure aluminum is shown to be dependent on the rate of formation. Some experiments are described which show that, even at low temperatures, the presence of a large ionic flux will permit the deformation of alumina providing a mechanism by which the growth stresses can be relieved.
Characterization of Pd-Composite Membrane Fabricated by Surfactant Induced Electroless Plating (SIEP): Effect of Grain Size on Hydrogen Permeability

Polycrystalline palladium (Pd) was deposited on micro-porous stainless steel (MPSS) substrate using a suitable surfactant of various concentrations in the electroless plating process. The micro-structural characterization was carried out using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). The concentrations of the surfactant were chosen as a function of critical micelle concentration (CMC) in order to elucidate the interaction of the surfactant in solid-liquid and solid-gas interface during grain coarsening. It appears that during electro-crystallization, the driving force between the newly formed crystallite and the originally coarsed grains depends on the relative size and crystalline configuration of the newly formed crystallite. This crystallite on the other hand is affected by the localized over potential, the presence of active nucleating particles, and the texture of MPSS surface and operating conditions. The size of the newly formed grain is smaller when the concentration of the surface-active agents is relatively higher. It suggests that the surfactant active polar group inherently participates in the reaction/deposition process and effectively activates the process of grain nucleation and agglomeration in electro-crystallization. The membranes of different grain sizes were fabricated in the presence of the cationic surfactant DTAB (dodecyltrimethyiammonium bromide) of various concentrations. DTAB concentration is expressed in critical micelle concentration (CM), which ranged from CMC × ½ to CMC × 4. Fabricated membranes of different grain size and distribution were also studied for hydrogen permeability and selectivity. Results show that membranes with agglomerated grains (higher grain size) possess relatively higher permeability and selectivity.
13C nuclear magnetic resonance spectra of amaryllidaceae alkaloids. I—alkaloids with the crinane skeleton

The13C NMR spectra of 15 Amaryllidaceae alkaloids with the crinane skeleton were measured and the chemical shifts unequivocally assigned. From the derived specific shift ranges, it is possible to establish both the complete oxygenation pattern of the 5, 10b‐ethanophenanthridine skeleton and its stereochemical arrangement.
Surface Complexation of Oxytetracycline by Magnetite: Effect of Solution Properties

Few studies have reported on the sorptive interactions of oxytetracycline (OTC), a veterinary antibiotic frequently detected in wastewater, surface water, and soils, with common Fe oxide minerals. The primary objective of this study was to investigate the sorption behavior of OTC on magnetite (Fe3O4) as a function of different solution properties such as pH, ionic strength, and initial OTC concentration. Results indicated that sorption of OTC by magnetite was rapid and complete within 24 h. The effect of ionic strength on sorption was negligible at low OTC surface coverage. The sorption envelope indicated that with increasing pH, OTC sorption on Fe3O4 decreased. Surface complexation modeling of magnetite–OTC interactions suggested the interactions of divalent anionic species of OTC with the magnetite surface. Four possible surface complexation reactions were postulated to explain the pH dependence of OTC sorption, indicating a rather complex potential sorption mechanism. Our results suggest that magnetite has the capability of immobilizing OTC in the environment, which may be of use to scientists in predicting the fate of OTC in Fe‐oxide‐rich soil.
Occurrence data uncover patterns of allopatric divergence and interspecies interactions in the evolutionary history of Sceloporus lizards

Abstract As shown from several long‐term and time‐intensive studies, closely related, sympatric species can impose strong selection on one another, leading to dramatic examples of phenotypic evolution. Here, we use occurrence data to identify clusters of sympatric Sceloporus lizard species and to test whether Sceloporus species tend to coexist with other species that differ in body size, as we would expect when there is competition between sympatric congeners. We found that Sceloporus species can be grouped into 16 unique bioregions. Bioregions that are located at higher latitudes tend to be larger and have fewer species, following Rapoport's rule and the latitudinal diversity gradient. Species richness was positively correlated with the number of biomes and elevation heterogeneity of each bioregion. Additionally, most bioregions show signs of phylogenetic underdispersion, meaning closely related species tend to occur in close geographic proximity. Finally, we found that although Sceloporus species that are similar in body size tend to cluster geographically, small‐bodied Sceloporus species are more often in sympatry with larger‐bodied Sceloporus species than expected by chance alone, whereas large‐bodied species cluster with each other geographically and phylogenetically. These results suggest that community composition in extant Sceloporus species is the result of allopatric evolution, as closely related species move into different biomes, and interspecies interactions, with sympatry between species of different body sizes. Our phyloinformatic approach offers unique and detailed insights into how a clade composed of ecologically and morphologically disparate species are distributed over large geographic space and evolutionary time.
Predictive value of immune cell counts and neutrophil-to-lymphocyte ratio for 28-day mortality in patients with sepsis caused by intra-abdominal infection

Abstract Background The current study aimed to evaluate the value of immune cell counts and neutrophil-to-lymphocyte ratio (NLR) when attempting to predict 28-day mortality. Methods We conducted an observational retrospective study that included consecutive septic patients. Severity scores on the first day and peripheral circulating immune cell counts (at day 1, day 3, day 5 and day 7 of admission) were collected during each patient’s emergency intensive care unit stay. We assessed the associations of peripheral circulating immune cell counts and NLR with the severity of illness. The relationships between 28-day mortality and peripheral circulating immune cell counts and NLR with were evaluated using Cox proportional cause-specific hazards models. Results A total of 216 patients diagnosed with sepsis caused by IAI were enrolled. The lymphocyte counts (days 1, 3, 5 and 7) and monocyte counts (days 3, 5 and 7) were significantly lower in non-survivors (n = 72) than survivors (n = 144). The NLR values at each time point were significantly higher in non-survivors. The day 1 lymphocyte counts, as well as the monocyte counts, were significantly lower in the highest-scoring group, when stratified by the Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores, than in the other groups (p < 0.05). The day 1 NLR was significantly higher in the highest-scoring group than in the other groups (p < 0.05). The day 5 and day 7 lymphocyte counts, day 3 and day 7 monocyte counts and day 7 NLR were significant predictors of 28-day mortality in the Cox proportional hazards models (day 5 lymphocyte count: hazard ratio, 0.123 (95% CI, 0.055–0.279), p < 0.001; day 7 lymphocyte count: hazard ratio, 0.115 (95% CI, 0.052–0.254), p < 0.001; day 3 monocyte count: hazard ratio, 0.067 (95% CI, 0.005–0.861), p = 0.038; day 7 monocyte count: hazard ratio, 0.015 (95% CI, 0.001–0.158), p < 0.001; day 7 NLR: hazard ratio, 0.773 (95% CI, 0.659–0.905), p = 0.001). Conclusions The results showed that circulating lymphocytes and monocytes were dramatically decreased within 7 days in non-survivors following sepsis from an IAI. Lymphocyte counts, monocyte counts and NLR appeared to be associated with the severity of illness, and they may serve as independent predictors of 28-day mortality in septic patients with IAIs.
Emissions and encapsulation of cadmium in CdTe PV modules during fires

Fires in residential and commercial properties are not uncommon. If such fires involve the roof, photovoltaic arrays mounted on the roof will be exposed to the flames. The amount of cadmium that can be released in fires involving CdTe PV and the magnitude of associated health risks has been debated. The current study aims in delineating this issue. Previous thermogravimetric studies of CdTe, involved pure CdTe and single‐glass PV modules. The current study is based on glass–glass CdTe PV modules which are the only ones in the market. Pieces of commercial CdTe photovoltaic (PV) modules, sizes 25×3 cm, were heated to temperatures up to 1100°C to simulate exposure to residential and commercial building fires. The temperature rate and duration in these experiments were defined according to standard protocols. Four different types of analysis were performed to investigate emissions and redistribution of elements in the matrix of heated CdTe PV modules: (1) measurements of sample weight loss as a function of temperature; (2) analyses of Cd and Te in the gaseous emissions; (3) Cd distribution in the heated glass using synchrotron X‐ray fluorescence microprobe analysis; and (4) chemical analysis for Cd and Te in the acid‐digested glass. These experiments showed that almost all (i.e., 99·5%) of the cadmium content of CdTe PV modules was encapsulated in the molten glass matrix; a small amount of Cd escaped from the perimeter of the samples before the two sheets of glass melted together. Adjusting for this loss in full‐size modules, results in 99·96% retention of Cd. Multiplying this with the probability of occurrence for residential fires in wood‐frame houses in the US (e.g., 10−4), results in emissions of 0·06 mg/GWh; the probability of sustained fires and subsequent emissions in adequately designed and maintained utility systems appears to be zero. Published in 2005 by John Wiley & Sons, Ltd.
A story from the Miocene: Clock‐dated phylogeny of Sisymbrium L. (Sisymbrieae, Brassicaceae)

Abstract Morphological variability and imprecise generic boundaries have hindered systematic, taxonomical, and nomenclatural studies of Sisymbrium L. (Brassicaceae, Sisymbrieae DC.). The members of this almost exclusively Old‐World genus grow mostly on highly porous substrates across open steppe, semidesert, or ruderal habitats in the temperate zone of the Northern Hemisphere and African subtropics. The present study placed the biological history of Sisymbrium L. into time and space and rendered the tribus Sisymbrieae as monotypic. Five nuclear‐encoded and three chloroplast‐encoded loci of approximately 85% of all currently accepted species were investigated. Several accessions per species covering their whole distribution range allowed for a more representative assessment of intraspecific genetic diversity. In the light of fossil absence, the impact of different secondary calibration methods and taxon sets on time spans was tested, and we showed that such a combinatorial nested dating approach is beneficial. Multigene phylogeny accompanied with a time divergence estimation analysis placed the onset and development of this tribus into the western Irano‐Turanian floristic region during the Miocene. Continuous increase in continentality and decrease in temperatures promoted the diversity of the Sisymbrieae, which invaded the open grasslands habitats in Eurasia, Mediterranean, and South Africa throughout the Pliocene and Pleistocene. Our results support the assumption of the Irano‐Turanian region as a biodiversity reservoir for adjacent regions.
Standard values for temporal muscle thickness in the Japanese population who undergo brain check-up by magnetic resonance imaging

Background: Skeletal muscle mass is an important factor for various diseases’ outcomes. The psoas muscle cross-sectional area on the abdominal computed tomography (CT), gait speed, and handgrip strength is used to measure it. However, it is difficult to measure the neurological patients’ muscle mass or function because (1) we do not perform abdominal CT. (2) Such patients have impaired consciousness, gait disturbance, paresis, and need of rest. Temporal muscle thickness (TMT) on magnetic resonance imaging (MRI) is now attractive for skeletal muscle volume indicator, but the reference values are not established. We herein investigated the standard value of the Japanese TMT using the brain check-up database by MRI. Methods: We retrospectively investigated 360 Japanese individuals from two institutions between 2017 and 2019. We measured TMT on the T1-weighted images in the previously reported way. The associations between TMT and other variables were analyzed. Results: TMT of 214 women and 146 men, ranging from 35 to 84 years old, was investigated. TMT ranged from 3.69 to 16.90 mm. Mean TMT values were significantly higher in men compared to women except for the over 70-year-old cohort. TMT was correlated to weight and body mass index in both sexes. Conclusion: This is the first retrospective study on the standard TMT values from the Japanese brain check-up database. Our results were just reference values, but these would be useful for further investigation in other neurosurgical and neurological diseases regarding muscle volume or sarcopenia.
Surgical treatment of giant mediastinal tumors

Background This study aims to evaluate the surgical treatment outcomes of giant mediastinal tumors. Methods Between July 2013 and July 2018, medical data of a total of 31 patients (26 males, 5 females; mean age 27.7±8.2 years; range, 18 to 56 years) who underwent radical surgery for a giant mediastinal tumor in our center and 47 cases (26 males, 21 females; mean age 45.4±16.7 years; range, 19 to 62 years) of giant mediastinal tumors retrieved from the National Center for Biotechnology Information database were retrospectively reviewed. Two-year overall survival and disease-free survival rates of the patients were evaluated. Results All patients underwent radical surgery (R0 resection). Symptoms caused by giant mediastinal tumors were relieved after radical surgery during follow-up. The two-year overall survival and disease-free survival rates were 100% and 86.7%, respectively, indicating a good prognosis. The surgical procedures for malignancies were more difficult than those for benign pathologies. Conclusion Radical surgery is the mainstay for treatment of giant mediastinal tumors to relieve symptoms in a short period of time and to achieve a good prognosis for up to two years, regardless of adjuvant therapy. The surgical route should be cautiously planned before radical surgery to reduce complications.