bluuebunny/crossref_metadata_2025_split huggingface dataset:
ACRE: Actor-Critic with Reward-Preserving Exploration
Authors: Kapoutsis Athanasios Ch. , Koutras Dimitrios I. , Korkas Christos D. , Kosmatopoulos Elias B. 
Published: August 2023

AbstractWhile reinforcement learning (RL) algorithms have generated impressive strategies for a wide range of tasks, the performance improvements in continuous-domain, real-world problems do not follow the same trend. Poor exploration and quick convergence to locally optimal solutions play a dominant role. Advanced RL algorithms attempt to mitigate this issue by introducing exploration signals during the training procedure. This successful integration has paved the way to introduce signals from the intrinsic exploration branch. ACRE algorithm is a framework that concretely describes the conditions for such an integration, avoiding transforming the Markov decision process into time varying, and as a result, making the whole optimization scheme brittle and susceptible to instability. The key distinction of ACRE lies in the way of handling and storing both extrinsic and intrinsic rewards. ACRE is an off-policy, actor-critic style RL algorithm that separately approximates the forward novelty return. ACRE is shipped with a Gaussian mixture model to calculate the instantaneous novelty; however, different options could also be integrated. Using such an effective early exploration, ACRE results in substantial improvements over alternative RL methods, in a range of continuous control RL environments, such as learning from policy-misleading reward signals. Open-source implementation is available here: https://github.com/athakapo/ACRE.
Productivity Decline Mechanisms in Gravel Packed Perforations
Authors: Berntsen Andreas Nicolas , Papamichos Euripides , Xie Xiyang , Li Gang , Yao Ziheng 
Published: August 2023

AbstractIn a cased hole gravel pack completion, perforations are packed with proppant to both mechanically support the perforation cavity, and to filter any produced sand before it reaches the surface. Poor perforation packing sometimes occurs in which the perforation is partially or completely unsupported, leading to earlier productivity reduction than in cases of good packing. We investigated productivity reduction and the associated mechanisms in a series of hollow cylinder experiments on outcrop and field cores with varying proppant packing. Packed perforations maintained significantly higher productivity than unsupported perforations by preventing macroscopic shear failure around the cavity and erosion due to sand production. Partial packing may in some instances maintain productivity almost as well as complete packing, but this likely depends on perforation orientation. Compaction tests and numerical simulations suggest that compaction failure is unlikely at the cavity wall in the current experiments, and that proppant-formation interface damage or proppant filtering of produced sand are more probable explanations for the productivity reduction seen in packed perforations.
Clinical, epidemiological, and genotypic characteristics of rotavirus infection in hospitalized infants and young children in Yunnan Province
Authors: Jiang Hongjun , Zhang Yu , Xu Xiaoyan , Li Xiaohan , Sun Yi , Fan Xin , Xu Ya , Su Ting , Zhang Guiqian , Dian Ziqin 
Published: August 2023

AbstractRotaviruses are the most important pathogenic cause of non-bacterial diarrhea in infants and children. Approximately 60% of hospital admissions for acute diarrhea worldwide are caused by rotavirus infection. Rotavirus infection and hospitalization among children in China are a social burden, resulting in economic loss. The prevalence and geographical distribution of rotavirus genotypes is variable, partially due to population migration. Due to the unique geographical conditions and climate in Yunnan Province, several viruses with new genotypes have emerged, and multiple genotypes have become co-epidemic. In this study, rotavirus infection screening and genetic characterization of epidemic strains were performed in 149,492 infants and children admitted to hospitals in six representative prefectures in Yunnan Province between 2019 and 2021. The prevalence of rotavirus infection was 13.39% and was highest in January and lowest in September. G9P[8] was the main epidemic rotavirus genotype. Other epidemic genotypes included G2P[4], G8P[8], G9P[4], G2P[8], G3P[8], G4P[8], G3P[4], and G4P[6]. Phylogenetic analysis revealed that locally epidemic strains were influenced by importation of strains from neighboring provinces and other Asian countries. These findings provide a scientific basis for rotavirus prevention and control and lay a foundation for preliminary studies to establish a rotavirus surveillance network in Yunnan Province.
Exploring the Frequency and Distribution of Ecological Non-monotonicity in Associations among Ecosystem Constituents
Authors: Hanusch Maximilian , He Xie , Janssen Stefan , Selke Julian , Trutschnig Wolfgang , Junker Robert R. 
Published: August 2023

AbstractComplex links between biotic and abiotic constituents are fundamental for the functioning of ecosystems. Although non-monotonic interactions and associations are known to increase the stability, diversity, and productivity of ecosystems, they are frequently ignored by community-level standard statistical approaches. Using the copula-based dependence measure qad, capable of quantifying the directed and asymmetric dependence between variables for all forms of (functional) relationships, we determined the proportion of non-monotonic associations between different constituents of an ecosystem (plants, bacteria, fungi, and environmental parameters). Here, we show that up to 59% of all statistically significant associations are non-monotonic. Further, we show that pairwise associations between plants, bacteria, fungi, and environmental parameters are specifically characterized by their strength and degree of monotonicity, for example, microbe–microbe associations are on average stronger than and differ in degree of non-monotonicity from plant–microbe associations. Considering directed and non-monotonic associations, we extended the concept of ecosystem coupling providing more complete insights into the internal order of ecosystems. Our results emphasize the importance of ecological non-monotonicity in characterizing and understanding ecosystem patterns and processes.
Comprehensive fully-automatic multi-depth grading of the clinical types of macular neovascularization in OCTA images
Authors: Vidal Plácido L. , de Moura Joaquim , Almuiña Pablo , Fernández María Isabel , Ortega Marcos , Novo Jorge 
Published: August 2023

AbstractOptical Coherence Tomography Angiography or OCTA represents one of the main means of diagnosis of Age-related Macular Degeneration (AMD), the leading cause of blindness in developed countries. This eye disease is characterized by Macular Neovascularization (MNV), the formation of vessels that tear through the retinal tissues. Four types of MNV can be distinguished, each representing different levels of severity. Both the aggressiveness of the treatment and the recovery of the patient rely on an early detection and correct diagnosis of the stage of the disease. In this work, we propose the first fully-automatic grading methodology that considers all the four clinical types of MNV at the three most relevant OCTA scanning depths for the diagnosis of AMD. We perform both a comprehensive ablation study on the contribution of said depths and an analysis of the attention maps of the network in collaboration with experts of the domain. Our proposal aims to ease the diagnosis burden and decrease the influence of subjectivity on it, offering a explainable grading through the visualization of the attention of the expert models. Our grading proposal achieved satisfactory results with an AUC of 0.9224 ± 0.0381. Additionally, the qualitative analysis performed in collaboration with experts revealed the relevance of the avascular plexus in the grading of all three types of MNV (despite not being directly involved in some of them). Thus, our proposal is not only able to robustly detect MNV in complex scenarios, but also aided to discover previously unconsidered relationships between plexuses.
A green approach for depolymerization of chitosan: applications in hydrogels
Authors: Tabassum Nishat , Ahmed Shoeb , Ittisaf Mohammad Muhtasim , Rakid-Ul-Haque Md. , Ali M. Azam 
Published: August 2023

AbstractChitooligosaccharides (COS) are depolymerized chains produced from the natural polymer chitosan and has been determined to exhibit improved biological activities, high solubility in neutral to slightly alkaline pH, because of the lower molecular weight (MW). This makes COS more attractive in biomedical applications. However, earlier studies focused on depolymerization techniques that were either cumbersome or expensive. Here, a convenient two-stage, green synthesis approach was developed and optimized, where gamma irradiation and oxidative degradation with H2O2 were used to depolymerize chitosan to produce COS for biomedical applications. The gamma radiation dose level, H2O2 degradation reaction’s temperature, time and H2O2 concentration were varied to obtain the mildest combination of reaction conditions. The most optimum set of conditions (15 kGy, 25oC, overnight reaction with 2% H2O2) yielded COS that was soluble in physiological pH range (7–8.5). The COS had a MW of 12.8 ± 1.6 kDa (which was a 95% reduction in MW), a 62.3% degree of deacetylation, and a crystallinity index of 33%. A photopolymerized hydrogel using this COS cross-linked with polyethylene glycol diacrylate (PEGDA) and carboxymethyl cellulose (CMC) was also developed. The hydrogel exhibited high swelling ratio (6.44–10.24), a porous morphology, a compression modulus of 4.5 ± 2.7 kPa (similar to soft tissues), and more than 95% biocompatibility with mammalian cells. This newly developed COS hydrogel involves a simple and green approach for the production of COS and shows promise as a scaffold for artificial soft tissue.
Learning from Other Communities: Organising Collective Action in a Grassroots Food-sharing Initiative
Authors: Berns Katie , Rossitto Chiara , Tholander Jakob 
Published: August 2023

AbstractThis paper illustrates the work of creating, infrastructuring, and organising a food-sharing community from the ground up. Drawing on Participatory Action Research (PAR) and a three-year engagement with FoodSharing Stockholm, the paper shows how the processes of starting up a grassroots initiative are shaped by participants’ direct experience and knowledge of similar initiatives. The analysis draws attention to: (1) how central activities such as recruiting volunteers, choosing digital tools, and establishing partnerships with food donors are conceived and organised, (2) the concrete challenges of sharing surplus food, such as adopting a distribution model, and negotiating fairness, and (3) how governance and decision-making models are adopted and (re)negotiated over time. The paper introduces the term Collective histories of organising to capture the impact that learning from previous experiences can have on communities’ efforts to set up and run; and re-orient design visions towards the consideration and adoption of existing sociotechnical practices, rather than always aiming at novel digital explorations. We outline three emerging dimensions that can characterise “Collective histories of organising” as a concept, (1) configuring capacities, (2) configuring sociotechnical practices, and (3) configuring participation. The paper contributes practical sensitivities to build, sustain, and infrastructure surplus food-sharing initiatives, where these three dimensions are discussed as central concerns designers and other food-sharing communities could learn from.
Insights into the life-cycle development of Meloidogyne enterolobii, M. incognita and M. javanica on tomato, soybean and maize
Authors: Collett Raymond Lesley , Rashidifard Milad , Marais Mariette , Daneel Mieke , Fourie Hendrika 
Published: August 2023

AbstractMeloidogyne enterolobii is a highly pathogenic nematode species that renders host plant resistance ineffective that exists for other species. The life-cycle development and duration of three Meloidogyne species, viz. M. enterolobii, M. incognita and M. javanica was determined in roots of three crops: tomato (‘Moneymaker’), soybean (‘DM-5953-RSF’) and maize (‘P-2432-R’) under glasshouse conditions. At different time intervals, 3-, 5-, 10-, 15-, 20-, and 25-days after inoculation (DAI), 20 randomly selected individuals, representing different life-stages of each species, were isolated from roots. Meloidogyne enterolobii had a quicker life cycle development compared to the other two species. Mature females were observed 15 DAI for all three species, but single eggs of M. enterolobii were present at 15 DAI opposed to egg masses only found 20 and 25 DAI for the other two species. Second generation motile J2 were observed for M. enterolobii and M. javanica from 20 DAI and at 25 DAI for M. incognita. Substantially less degree days (DD) were recorded for M. enterolobii being 216 for tomato, 195 for soybean and 232 for maize; for M. incognita it was 292 for tomato, 264 for soybean and 314 for maize; and for M. javanica it was 276 for tomato, 248 for soybean and 298 for maize. The use of genotypes with shorter growing periods is suggested to reduce the number of generations of M. enterolobii which is foreseen to potentially result in lower population densities and less crop damage.
Influence of Isomeric Composition and Sample Handling on the Liquid Density of Hydrofluorethers Measured by Vibrating Tube Densimeter at 0.1 MPa
Authors: Prokopová Olga , Blahut Aleš , Hajduch Jan , Kučnirová Kateřina , Čenský Miroslav , Aminian Ali , Richter Markus , Vinš Václav 
Published: August 2023

AbstractHydrofluoroethers (HFEs) represent a new family of promising engineering fluids suitable for technical cleaning and cooling of electronic and magnetic devices or as admixtures in refrigerant blends. Here, we report accurate data for the liquid density at 0.1 MPa and temperatures from $$273.15\,\text{K}$$

273.15

K

to $$343.15\,\text{K}$$

343.15

K

for a series of five HFEs, namely, HFE-7000, HFE-7100, HFE-7200, HFE-7300, and HFE-7500. A highly sensitive vibrating tube densimeter with a borosilicate glass U-tube calibrated according to the procedure by Prokopová et al. (J Chem Thermodyn 173:106855, 2022) provided density data with an expanded uncertainty ($$k=2$$

k
=
2

) of $$0.13\,\text{kg}\cdot \text{m}^{-3}$$

0.13

kg
·

m

-
3

. Influences such as sample degassing, water content, or sample temperature before its dosing into the densimeter are discussed. Thanks to the high sensitivity of the used densimeter, an unexpected shift in the density of different HFE-7100 and HFE-7200 liquid samples was detected. Unlike other HFEs, HFE-7100 and HFE-7200 are mixtures of two hardly separable isomers, which were so far considered having identical thermophysical properties. Utilizing nuclear magnetic resonance spectroscopy, the ratio of n-isomer and iso-isomer was inspected for various liquid samples. In the range of iso-isomer mole fraction from 0.61 to 0.77, the new measurements revealed density differences of more than $$5\,\text{kg}\cdot \text{m}^{-3}$$

5

kg
·

m

-
3

in case of HFE-7100 and of about $$3\,\text{kg}\cdot \text{m}^{-3}$$

3

kg
·

m

-
3

in case of HFE-7200. Consequently, for some applications, the properties of different HFE isomers cannot be considered identical. The Rackett-type correlation for the saturated liquid density was fitted using the new and the literature data.
Kuroshio water intrusion into the subarctic region in the western North Pacific Ocean and analyses of the Lagrangian coherent structure
Authors: Matsuta Takuro , Mitsudera Humio 
Published: August 2023

AbstractPrevious studies have suggested that the quasi-stationary jets, sometimes called the “Isoguchi jets” in the western North Pacific Ocean, regulate the warm and salty conditions in the transition domain between the Subarctic Boundary and the Subarctic Front. Here, we show that mesoscale eddies and interannual/decadal modulations are responsible for the Kuroshio water intrusion into the transition domain. A case study using the Lagrangian coherent structure suggests that the northward shift of the Kuroshio Extension forms a favorable velocity field for the Kuroshio water intrusion around the Subarctic Boundary, while the geometric structure inside the Isoguchi jet is quasi-permanent.
Improving concave point detection to better segment overlapped objects in images
Authors: Miró-Nicolau Miquel , Moyà-Alcover Gabriel , González-Hidalgo Manuel , Jaume-i-Capó Antoni 
Published: August 2023

AbstractThis study presents a method to improve state-of-the-art concave point detection methods as the first step towards effectively segmenting overlapping objects in images. The approach relies on analysing the curvature of the object contour. This method comprises three main steps. First, the original image is preprocessed to obtain the curvature value at each contour point. Second, the regions with higher curvatures are selected and a recursive algorithm is applied to refine previously selected regions. Finally, a concave point is obtained for each region by analysing the relative position of their neighbourhood. Furthermore, the experimental results indicate that improving the detection of concave points leads to better division of clusters. To evaluate the quality of the concave point detection algorithm, a synthetic dataset was constructed to simulate the presence of overlapping objects. This dataset includes the precise location of concave points, which serve as the ground truth for evaluation. As a case study, the performance of a well-known application, such as the splitting of overlapping cells in images of peripheral blood smears samples from patients with sickle cell anaemia, was evaluated. We used the proposed method to detect concave points in cell clusters and then separated these clusters by ellipse fitting.
A 3D pose estimation framework for preterm infants hospitalized in the Neonatal Unit
Authors: Soualmi Ameur , Ducottet Christophe , Patural Hugues , Giraud Antoine , Alata Olivier 
Published: August 2023

AbstractInfant pose estimation is crucial in different clinical applications, including preterm automatic general movements assessment. Recent infant pose estimation methods are limited by a lack of real clinical data and are mainly focused on 2D detection. We introduce a stereoscopic system for infants’ 3D pose estimation, based on fine-tuning state-of-the-art 2D human pose estimation networks on a large, real, and manually annotated dataset of infants’ images. Our dataset contains over 88k images, collected from 175 videos from 53 premature infants born <33 weeks of gestational age (GA), acquired within the Neonatology department of the Centre Hospitalier Universitaire de Saint Etienne, France, between 32 and 41 weeks of GA. This framework significantly reduced the pose estimation error compared to existing 2D infant pose estimation networks. It achieved a mean error of 1.72 cm on 18000 stereoscopic images in the 3D pose estimation task. This framework is the first 3D pose estimation tool dedicated to preterm infants hospitalized in the Neonatal Unit that does not depend on any visual markers or infrared cameras.
Detecting and approximating decision boundaries in low-dimensional spaces
Authors: Grajewski Matthias , Kleefeld Andreas 
Published: August 2023

AbstractA method for detecting and approximating fault lines or surfaces, respectively, or decision curves in two and three dimensions with guaranteed accuracy is presented. Reformulated as a classification problem, our method starts from a set of scattered points along with the corresponding classification algorithm to construct a representation of a decision curve by points with prescribed maximal distance to the true decision curve. Hereby, our algorithm ensures that the representing point set covers the decision curve in its entire extent and features local refinement based on the geometric properties of the decision curve. We demonstrate applications of our method to problems related to the detection of faults, to multi-criteria decision aid and, in combination with Kirsch’s factorization method, to solving an inverse acoustic scattering problem. In all applications we considered in this work, our method requires significantly less pointwise classifications than previously employed algorithms.
Demographic and socioeconomic effects of environmental policies: the 1927 special goat tax and mountain depopulation in Italy
Authors: Morettini Gabriele 
Published: August 2023

AbstractThe research aims to assess the demographic impact related with the implementation of an environmental policy, which affects food availability in economically and environmentally fragile settings, dependent on few, unstable resources. The paper addresses this topic from a particular perspective, namely the special goat tax issued in Italy in 1927. I focus on the goat breeding because of its ecological footprint and the key role on population’s livelihood in marginal lands. Methodologically, the paper combines quantitative and qualitative sources. The analysis of demographic dynamics in a broad set of Italian mountain municipalities over the period 1911–1971 is matched with a qualitative part, based on a careful reading of the coeval survey on mountain depopulation. Findings of the analysis highlight that the goat tax undermined food security promoted outmigration and shrinkage in municipalities that were more dependent on goat breeding only. In addition, the 1927 law generated power struggles between landowner and local communities and between collective and private properties. Such results show that socially-blind, top-down environmental policies could exacerbate inequalities, food insecurity and power conflicts that threaten the effective implementation of the law. An ecological transition must be combined with social inclusion, constant care to the governance and power relations in order to extend public support and make regulations more effective.