bluuebunny/crossref_metadata_2025_split huggingface dataset:
An efficient single shot detector with weight-based feature fusion for small object detection
Authors: Li Ming , Pi Dechang , Qin Shuo 
Published: June 2023

AbstractObject detection has been widely applied in various fields with the rapid development of deep learning in recent years. However, detecting small objects is still a challenging task because of the limited information in features and the complex background. To further enhance the detection accuracy of small objects, this paper proposes an efficient single-shot detector with weight-based feature fusion (WFFA-SSD). First, a weight-based feature fusion block is designed to adaptively fuse information from several multi-scale feature maps. The feature fusion block can exploit contextual information for feature maps with large resolutions. Then, a context attention block is applied to reinforce the local region in the feature maps. Moreover, a pyramids aggregation block is applied to combine the two feature pyramids to classify and locate target objects. The experimental results demonstrate that the proposed WFFA-SSD achieves higher mean Average Precision (mAP) under the premise of ensuring real-time performance. WFFA-SSD increases the mAP of the car by 4.12% on the test set of the CARPK.
Nanosilica treatment enables moisture-resistant hydrophobic arc welding covered electrodes
Authors: Pasandeh Mohammadreza , Pouranvari Majid 
Published: June 2023

AbstractControlling the moisture content of the electrode-covering is crucial in the production of defect-free, high-quality welds during shielded metal arc welding of steels. The welding industry has long faced the challenge of the high susceptibility of basic electrodes (e.g., E7018) to moisture absorption. In this paper, we demonstrate that applying a nanosilica coating to the surface of the E7018 electrode-covering using a dip-coating technique can effectively reduce the moisture absorption capability of the electrode-covering. The moisture measurement results before and after exposure to a moist environment of 80% humidity and a temperature of 27 °C for 9 h indicate that the moisture absorption values of conventional and nano-treated E7018 electrodes during exposure are 0.67 wt% and 0.03 wt%, respectively. While reducing the size of the pores on the surface of the electrode-covering can to some extent enhance the resistance to moisture absorption, it has been identified that turning the wetting behavior of the electrode-covering surface from hydrophilic to hydrophobic by the nanosilica coating is the most effective mechanism that contributes to the enhanced moisture absorption resistance of the nanosilica-treated electrode-covering. The results indicate that this approach does not have any deleterious effects on the chemical analysis and tensile properties of the weld metal. This simple modification to the electrode-covering can be generally applied to a wide range of electrode-covering types to produce hydrophobic, moisture-resistant electrodes.
Recovery of fuel from real waste oily sludge via a new eco-friendly surfactant material used in a digital baffle batch extraction unit
Authors: Humadi Jasim I. , Jafar Saad A. , Ali Nisreen S. , Ahmed Mustafa A. , Mzeed Mohammed J. , Al-Salhi Raheem J. , Saady Noori M. Cata , Majdi Hasan Sh. , Zendehboudi Sohrab , Albayati Talib M. 
Published: June 2023

AbstractThis study focused on developing a new cocktail extraction agent (CEA) composed of solvent and a new surfactant material (SM) for enhancing the efficiency of fuel recovery from real waste oil sludge (WSO). The effects of different solvents (e.g. methyl ethyl ketone (MEK), naphtha, petrol and kerosene), SMs (Dowfax and sodium thiosulfate), extraction time (10–20 min), extraction temperatures (20–60 °C) and CEA/sludge ratios (1–4) on the extraction performance were investigated. SMs and DBBE design enhanced the extraction efficiency by increasing the dispersion of solvent in WSO and enhancing the mixing and mass transfer rates. Results proved that Dowfax was the best SM for oil recovery under various conditions. The best CEA (e.g. MEK and Dowfax) provides the maximum fuel recovery rate of 97% at a period of 20 min, temperature of 60 °C and 4:1 CEA/sludge ratio. The produced fuel was analysed and fed to the distillation process to produce diesel oil. The characteristics of diesel oil were measured, and findings showed that it needs treatment processes prior its use as a finished fuel.
In-vivo corneal confocal microscopy: Imaging analysis, biological insights and future directions
Authors: Chiang Jeremy Chung Bo , Roy Maitreyee , Kim Juno , Markoulli Maria , Krishnan Arun V. 
Published: June 2023

AbstractIn-vivo corneal confocal microscopy is a powerful imaging technique which provides clinicians and researcher with the capabilities to observe microstructures at the ocular surfaces in significant detail. In this Mini Review, the optics and image analysis methods with the use of corneal confocal microscopy are discussed. While novel insights of neuroanatomy and biology of the eyes, particularly the ocular surface, have been provided by corneal confocal microscopy, some debatable elements observed using this technique remain and these are explored in this Mini Review. Potential improvements in imaging methodology and instrumentation are also suggested.
Inhibition of the voltage-gated potassium channel Kv1.5 by hydrogen sulfide attenuates remodeling through S-nitrosylation-mediated signaling
Authors: Al-Owais Moza M. , Hettiarachchi Nishani T. , Dallas Mark L. , Scragg Jason L. , Lippiat Jonathan D. , Holden Arun V. , Steele Derek S. , Peers Chris 
Published: June 2023

AbstractThe voltage-gated K+ channel plays a key role in atrial excitability, conducting the ultra-rapid rectifier K+ current (IKur) and contributing to the repolarization of the atrial action potential. In this study, we examine its regulation by hydrogen sulfide (H2S) in HL-1 cardiomyocytes and in HEK293 cells expressing human Kv1.5. Pacing induced remodeling resulted in shorting action potential duration, enhanced both Kv1.5 channel and H2S producing enzymes protein expression in HL-1 cardiomyocytes. H2S supplementation reduced these remodeling changes and restored action potential duration through inhibition of Kv1.5 channel. H2S also inhibited recombinant hKv1.5, lead to nitric oxide (NO) mediated S-nitrosylation and activated endothelial nitric oxide synthase (eNOS) by increased phosphorylation of Ser1177, prevention of NO formation precluded these effects. Regulation of Ikur by H2S has important cardiovascular implications and represents a novel and potential therapeutic target.
Variable-order topological insulators
Authors: Yang Yating , Sun Handa , Lu Jiuyang , Huang Xueqin , Deng Weiyin , Liu Zhengyou 
Published: June 2023

AbstractTopological insulators, either the first-order or the higher-order, experience generally a transition to a trivial phase or a topological one of the same order through the gap closing and reopening procedure. Here, we report a topological insulator, which switches directly between the first and higher orders, with only varying the hoppings and without breaking the symmetry. The phase transition of the first and higher orders is originated from a competition mechanism between the nearest and second-nearest neighbor interactions. This variable-order topological insulator is implemented in a two-dimensional phononic crystal, and the one-dimensional helical edge states, which signal the first-order phase, and the zero-dimensional corner states, which signal the second-order one, are demonstrated in the simulations and experiments. Our study gives insight to the topological states of different orders.
Constructing soils for climate-smart mining
Authors: Ruiz Francisco , Safanelli José Lucas , Perlatti Fabio , Cherubin Maurício Roberto , Demattê José A. M. , Cerri Carlos Eduardo Pellegrino , Otero Xosé Luis , Rumpel Cornelia , Ferreira Tiago Osório 
Published: June 2023

AbstractSurface mining is inherently linked to climate change, but more precise monitoring of carbon dioxide (CO2) emissions is necessary. Here we combined the geolocation of mine sites and carbon stock datasets to show that if all legal active mining sites in Brazil are exploited over the next decades, 2.55 Gt of CO2 equivalent (CO2eq) will be emitted due to the loss of vegetation (0.87 Gt CO2eq) and soil (1.68 Gt CO2eq). To offset these emissions, we propose constructing soils (Technosols) from mine and other wastes for mine reclamation. We show that this strategy could potentially offset up to 60% (1.00 Gt CO2eq) of soil-related CO2 emissions. When constructed with suitable parent materials, Technosols can also restore important soil-related ecosystem services while improving waste management. The construction of healthy Technosols stands out as a promising nature-based solution towards carbon-neutral mining and should, therefore, be considered in future environmental policies of major mining countries.
Decadal increase in groundwater inorganic carbon concentrations across Sweden
Authors: Klaus Marcus 
Published: June 2023

AbstractGroundwater is one of the largest continental carbon reservoirs and tightly linked to globally important carbon fluxes such as uptake on land, degassing from inland waters and delivery to oceans. Despite emerging evidence that these fluxes are sensitive to environmental changes, long-term carbon dynamics in groundwater remain widely unknown. Here I show that dissolved inorganic carbon and carbon dioxide concentrations in groundwater, calculated from environmental monitoring data (e.g. alkalinity, pH), have increased on average by 28% and 49%, respectively, across Sweden during 1980–2020. I attribute the observed changes mainly to a partial recovery from atmospheric sulfate deposition and associated shifts in weathering pathways, but also to enhanced soil respiration. The results highlight previously neglected long-term and large-scale dynamics in groundwater carbon cycling. These dynamics should be included in carbon cycle models for accurate evaluations and predictions of the effects of environmental changes on landscape and global carbon stocks and fluxes.
Evolutionary implications of SARS-CoV-2 vaccination for the future design of vaccination strategies
Authors: Rouzine Igor M. , Rozhnova Ganna 
Published: June 2023

AbstractOnce the first SARS-CoV-2 vaccine became available, mass vaccination was the main pillar of the public health response to the COVID-19 pandemic. It was very effective in reducing hospitalizations and deaths. Here, we discuss the possibility that mass vaccination might accelerate SARS-CoV-2 evolution in antibody-binding regions compared to natural infection at the population level. Using the evidence of strong genetic variation in antibody-binding regions and taking advantage of the similarity between the envelope proteins of SARS-CoV-2 and influenza, we assume that immune selection pressure acting on these regions of the two viruses is similar. We discuss the consequences of this assumption for SARS-CoV-2 evolution in light of mathematical models developed previously for influenza. We further outline the implications of this phenomenon, if our assumptions are confirmed, for the future design of SARS-CoV-2 vaccination strategies.
Real-time 4D tracking of airborne virus-laden droplets and aerosols
Authors: Pal Devendra , Amyot Marc , Liang Chen , Ariya Parisa A. 
Published: June 2023

AbstractThere is currently no real-time airborne virus tracking method, hindering the understanding of rapid virus changes and associated health impacts. Nano-digital in-line holographic microscopy (Nano-DIHM) is a lensless technology that can directly obtain the interference patterns of objects by recording the scattered light information originating from the objects. Here, we provide evidence for real-time physicochemical tracking of virus-laden droplets and aerosols in the air using desktop label-free Nano-DIHM. The virus interference patterns, as single and ensemble particles, were imaged by the Nano-DIHM with 32.5 ms resolution. The next-generation Stingray and Octopus software was used to automate object detection, characterization and classification from the recorded holograms. The detection system was demonstrated to detect active MS2 bacteriophages, inactivated SARS-CoV-2 and RNA fragments, and an MS2 mixture with metallic and organic compounds. This work demonstrates the feasibility of using Nano-DIHM to provide rapid virus detection to improve transmission management in real time.
Commentary on: Divalent metal cofactors differentially modulate RadA-mediated strand invasion and exchange in Saccharolobus solfataricus
Authors: Mangialavori Irene C. 
Published: June 2023

Abstract
RecA ATPases are a family of proteins that catalyzes the exchange of complementary DNA regions via homologous recombination. They are conserved from bacteria to humans and are crucial for DNA damage repair and genetic diversity. In this work, Knadler et al. examine how ATP hydrolysis and divalent cations impact the recombinase activity of Saccharolobus solfataricus RadA protein (ssoRadA). They find that the ssoRadA-mediated strand exchange depends on ATPase activity. The presence of Manganese reduces ATPase activity and enhances strand exchange, while calcium inhibits ATPase activity by preventing ATP binding to the protein, yet destabilizes the nucleoprotein ssoRadA filaments, allowing strand exchange regardless of the ATPase activity. Although RecA ATPases are highly conserved, this research offers intriguing new evidence that each member of the family requires individual evaluation.
Harnessing extremophilic carboxylesterases for applications in polyester depolymerisation and plastic waste recycling
Authors: Williams Gwion B. , Ma Hairong , Khusnutdinova Anna N. , Yakunin Alexander F. , Golyshin Peter N. 
Published: June 2023

Abstract
The steady growth in industrial production of synthetic plastics and their limited recycling have resulted in severe environmental pollution and contribute to global warming and oil depletion. Currently, there is an urgent need to develop efficient plastic recycling technologies to prevent further environmental pollution and recover chemical feedstocks for polymer re-synthesis and upcycling in a circular economy. Enzymatic depolymerization of synthetic polyesters by microbial carboxylesterases provides an attractive addition to existing mechanical and chemical recycling technologies due to enzyme specificity, low energy consumption, and mild reaction conditions. Carboxylesterases constitute a diverse group of serine-dependent hydrolases catalysing the cleavage and formation of ester bonds. However, the stability and hydrolytic activity of identified natural esterases towards synthetic polyesters are usually insufficient for applications in industrial polyester recycling. This necessitates further efforts on the discovery of robust enzymes, as well as protein engineering of natural enzymes for enhanced activity and stability. In this essay, we discuss the current knowledge of microbial carboxylesterases that degrade polyesters (polyesterases) with focus on polyethylene terephthalate (PET), which is one of the five major synthetic polymers. Then, we briefly review the recent progress in the discovery and protein engineering of microbial polyesterases, as well as developing enzyme cocktails and secreted protein expression for applications in the depolymerisation of polyester blends and mixed plastics. Future research aimed at the discovery of novel polyesterases from extreme environments and protein engineering for improved performance will aid developing efficient polyester recycling technologies for the circular plastics economy.
Overview of frequency control techniques in power systems with high inverter‐based resources: Challenges and mitigation measures
Authors: Al Kez Dlzar , Foley Aoife M. , Ahmed Faraedoon , Morrow D. John 
Published: June 2023

AbstractPower systems are rapidly transitioning towards having an increasing proportion of electricity from inverter‐based resources (IBR) such as wind and solar. An inevitable consequence of a power system transition towards 100% IBR is the loss of synchronous generators with their associated inertia, frequency, and voltage control mechanisms. To ensure future grid needs can be met, the source of system services to meet these needs must change from synchronous plants to IBR. Under this context, the main objective is to extensively review grid frequency stability challenges concerning the massive integration of IBR from the perspective of system operators. Following that, the newly established international fast frequency response services in different renewable dominant power systems to address low inertia challenges are compared from various perspectives. Finally, potential solutions based on various renewable enabling technologies and renewable sources are investigated from the standpoint of their expectation to play an active role in the energy system and to provide a wide range of system frequency services. The findings of this study provide a deep understanding of prospective frequency control solutions and an actionable dataset that will support various research and policy needs as we approach net‐zero targets.
Identification of a 4.3 billion year old asteroid family and planetesimal population in the Inner Main Belt
Authors: Ferrone S. , Delbo M. , Avdellidou C. , Melikyan R. , Morbidelli A. , Walsh K. , Deienno R. 
Published: June 2023

Context. Understanding the conditions that lead to the formation of planetesimals – the building blocks of planets - and their initial size distribution is a central problem of modern planetology. While most of these original planetesimals were accreted onto the terrestrial planets and the cores of the giant planets, some were also stranded in the main belt, where 4.5 Gyr of collisional evolution broke most of them into families of collisional asteroid fragments. However, some planetesimals survived, and are still hidden amongst asteroid fragments in the main belt.
Aims. We make use of astronomical data to identify these leftover planetesimals amongst all other asteroids. Our search is based on separating planetesimal survivors from families of asteroids generated by collisions. Namely, we aim to identify and “clean” the main belt of collisional family members: by doing so, we would be left with the surviving members of the original planetesimals.
Methods. We focus here on the inner portion of the main belt for asteroids with intermediate to high albedo. It is known that current asteroid family catalogs are not suitable for the aforementioned cleaning; they are conservative and only one-quarter of the known asteroids are associated with the approximately 120 distinct asteroid families. We therefore developed methods to inclusively link asteroids to known collisional families in order to better capture their extent. Namely, we apply a hierarchical clustering method (HCM) on asteroids filtered according to the V-shape of the Yarkovsky drift of each family in order to reassess family membership (V-shape-constrained HCM). The identified families were removed and the remaining background population was searched for previously undetected collisional families.
Results. We succeed in using our V-shape-constrained HCM to link family “halos” to their cores. After removing these reassessed families from the asteroid population, our V-shape search reveals a previously unknown collisional family of S-type asteroids in the inner main belt with an age of 4.3 ± 1.7 Gyr and a significance level of 3.4σ. When this ancient collisional family is removed, 34 planetesimals are identified and their size-frequency distribution is presented.
Conclusions. The asteroid belt has two components: planetesimals and collisional fragments. The cumulative size-frequency distribution of planetesimals has a steep power-law index for bodies larger than 100 km in diameter and a much smaller power-law index for planetesimals smaller than 100 km.
Extreme-ultraviolet brightenings in the quiet Sun: Signatures in spectral and imaging data from the Interface Region Imaging Spectrograph
Authors: Nelson C. J. , Auchère F. , Aznar Cuadrado R. , Barczynski K. , Buchlin E. , Harra L. , Long D. M. , Parenti S. , Peter H. , Schühle U. , Schwanitz C. , Smith P. , Teriaca L. , Verbeeck C. , Zhukov A. N. , Berghmans D. 
Published: June 2023

Context. Localised transient EUV brightenings, sometimes named ‘campfires’, occur throughout the quiet Sun. However, there are still many open questions about these events, in particular regarding their temperature range and dynamics.
Aims. We aim to determine whether any transition region response can be detected for small-scale extreme-ultraviolet (EUV) brightenings and, if so, to identify whether the measured spectra correspond to any previously reported bursts in the transition region, such as explosive events (EEs).
Methods. EUV brightenings were detected in a ∼29.4 min dataset sampled by the Solar Orbiter Extreme Ultraviolet Imager (EUI) on 8 March 2022 using an automated detection algorithm. Any potential transition region response was inferred through analysis of imaging and spectral data sampled through coordinated observations conducted by the Interface Region Imaging Spectrograph (IRIS).
Results. EUV brightenings display a range of responses in IRIS slit-jaw imager (SJI) data. Some events have clear signatures in the Mg II and Si IV SJI filters, whilst others have no discernible counterpart. Both extended and more complex EUV brightenings are sometimes found to have responses in IRIS SJI data. Examples of EUI intensities peaking before, during, and after their IRIS counterparts were found in light curves constructed co-spatial to EUV brightenings. Importantly, therefore, it is likely that not all EUV brightenings are driven in the same way, with some events seemingly being magnetic reconnection driven and others not. A single EUV brightening occurred co-spatial to the IRIS slit, with the returned spectra matching the properties of EEs.
Conclusions. EUV brightening is a term used to describe a range of small-scale events in the solar corona. The physics behind all EUV brightenings is likely not the same. More research is therefore required to assess their importance for global questions in the field, such as coronal heating.