bluuebunny/crossref_metadata_2025 huggingface dataset:
Brans–Dicke Unimodular Gravity
Authors: Almeida Alexandre M. R. , Fabris Júlio C. , Daouda Mahamadou Hamani , Kerner Richard , Velten Hermano , Hipólito-Ricaldi Willian S.
Published: August 2022

We propose a unimodular version of the Brans–Dicke theory designed with a constrained Lagrangian formulation. The resulting field equations are traceless. The vacuum solutions in the cosmological background reproduce the corresponding solutions of the usual Brans–Dicke theory but with a cosmological constant term. A perturbative analysis of the scalar modes is performed and stable and unstable configurations appear, in contrast with the Brans–Dicke case for which only stable configurations occur. On the other hand, tensorial modes in this theory remain the same as in the traditional Brans–Dicke theory.
Search for Gamma-ray Emission from Accretion Flares of Tidal Disruption Events Possibly Associated with the IceCube Neutrinos
Authors: Peng Fang-Kun , Zhu Ben-Yang , Sun Lu-Ming , Shu Xin-Wen , Wang Xiang-Yu
Published: August 2022

Outflows or disk-coronas generated in tidal disruption events (TDEs) of supermassive black holes have been suggested as possible sites of high-energy neutrinos. Three TDEs (AT2019dsg, AT2019fdr and AT2019aalc) have been claimed to be associated with high-energy astrophysical neutrinos in multi-messenger follow-ups. No GeV photons have been detected accompanying the neutrino for the three sources. In this work, we searched for the high-energy gamma-ray emission from a larger sample of TDE candidates observed by the Zwicky Transient Facility (ZTF). No significant GeV emission was observed, and the upper limits of the gamma-ray emission flux are reported. We then performed a stacking analysis for the sample sources and found that the collective gamma-ray emission of this class of sources was also not bright enough to be detected by the Fermi Large Area Telescope (Fermi-LAT). The nondetection of the high-energy gamma-ray emission from the sample TDEs could be due to the fact that the high-energy gamma rays are absorbed by soft photons in the source. Using a model-based hypothesis, the upper limit on the emission radius of the neutrino production is obtained for these TDEs: R<1016 cm for typical TDE parameter values.
Ultra-High-Energy Astroparticles as Probes for Lorentz Invariance Violation
Authors: Lang Rodrigo Guedes , Martínez-Huerta Humberto , de Souza Vitor
Published: August 2022

Compelling evidence for Lorentz invariance violation (LIV) would demand a complete revision of modern physics. Therefore, searching for a signal or extending the validity of the invariance is fundamental for building our understanding of the extreme phenomena in the Universe. In this paper, we review the potential of ultra-high-energy astroparticles in setting limits on LIV. The standard framework of LIV studies in astroparticle physics is reviewed and its use on the electromagnetic and hadronic sectors are discussed. In particular, the current status of LIV tests using experimental data on ultra-high-energy photons and cosmic rays is addressed. A detailed discussion with improved argumentation about the LIV kinematics of the relevant interactions is shown. The main previous results are presented together with new calculations based on recently published astrophysical models.
Phenotypic and Genetic Studies of the Viral Lineage Associated with the Recent Yellow Fever Outbreak in Brazil
Authors: Furtado Nathália Dias , Gómez Mariela Martínez , de Mello Iasmim Silva , Fernandes Déberli Ruiz , Bonaldo Myrna Cristina
Published: August 2022

Yellow fever virus (YFV) caused an outbreak in the Brazilian Southeast from 2016 to 2019, of the most significant magnitude since the 1900s. An investigation of the circulating virus revealed that most of the genomes detected in this period carried nine unique amino acid polymorphisms, with eight located in the non-structural proteins NS3 and NS5, which are pivotal for viral replication. To elucidate the effect of these amino acid changes on viral infection, we constructed viruses carrying amino acid alterations in NS3 and NS5, performed infection in different cells, and assessed their neurovirulence in BALB/c mice and infected AG129 mice. We observed that the residues that compose the YFV 2016–2019 molecular signature in the NS5 protein might have been related to an attenuated phenotype, and that the alterations in the NS3 protein only slightly affected viral infection in AG129 mice, increasing to a low extent the mortality rate of these animals. These results contributed to unveiling the role of specific naturally occurring amino acid changes in the circulating strain of YFV in Brazil.
Establishing an In Vitro System to Assess How Specific Antibodies Drive the Evolution of Foot-and-Mouth Disease Virus
Authors: King David J. , Freimanis Graham , Neil Chris , Shaw Andrew , Tuthill Tobias J. , Laing Emma , King Donald P. , Lasecka-Dykes Lidia
Published: August 2022

Viruses can evolve to respond to immune pressures conferred by specific antibodies generated after vaccination and/or infection. In this study, an in vitro system was developed to investigate the impact of serum-neutralising antibodies upon the evolution of a foot-and-mouth disease virus (FMDV) isolate. The presence of sub-neutralising dilutions of specific antisera delayed the onset of virus-induced cytopathic effect (CPE) by up to 44 h compared to the untreated control cultures. Continued virus passage with sub-neutralising dilutions of these sera resulted in a decrease in time to complete CPE, suggesting that FMDV in these cultures adapted to escape immune pressure. These phenotypic changes were associated with three separate consensus-level non-synonymous mutations that accrued in the viral RNA-encoding amino acids at positions VP266, VP280 and VP1155, corresponding to known epitope sites. High-throughput sequencing also identified further nucleotide substitutions within the regions encoding the leader (Lpro), VP4, VP2 and VP3 proteins. While association of the later mutations with the adaptation to immune pressure must be further verified, these results highlight the multiple routes by which FMDV populations can escape neutralising antibodies and support the application of a simple in vitro approach to assess the impact of the humoral immune system on the evolution of FMDV and potentially other viruses.
Rotavirus C Replication in Porcine Intestinal Enteroids Reveals Roles for Cellular Cholesterol and Sialic Acids
Authors: Guo Yusheng , Raev Sergei , Kick Maryssa K. , Raque Molly , Saif Linda J. , Vlasova Anastasia N.
Published: August 2022

Rotaviruses (RVs) are a significant cause of severe diarrheal illness in infants and young animals, including pigs. Group C rotavirus (RVC) is an emerging pathogen increasingly reported in pigs and humans worldwide, and is currently recognized as the major cause of gastroenteritis in neonatal piglets that results in substantial economic losses to the pork industry. However, little is known about RVC pathogenesis due to the lack of a robust cell culture system, with the exception of the RVC Cowden strain. Here, we evaluated the permissiveness of porcine crypt-derived 3D and 2D intestinal enteroid (PIE) culture systems for RVC infection. Differentiated 3D and 2D PIEs were infected with porcine RVC (PRVC) Cowden G1P[1], PRVC104 G3P[18], and PRVC143 G6P[5] virulent strains, and the virus replication was measured by qRT-PCR. Our results demonstrated that all RVC strains replicated in 2D-PIEs poorly, while 3D-PIEs supported a higher level of replication, suggesting that RVC selectively infects terminally differentiated enterocytes, which were less abundant in the 2D vs. 3D PIE cultures. While cellular receptors for RVC are unknown, target cell surface carbohydrates, including histo-blood-group antigens (HBGAs) and sialic acids (SAs), are believed to play a role in cell attachment/entry. The evaluation of the selective binding of RVCs to different HBGAs revealed that PRVC Cowden G1P[1] replicated to the highest titers in the HBGA-A PIEs, while PRVC104 or PRVC143 achieved the highest titers in the HBGA-H PIEs. Further, contrasting outcomes were observed following sialidase treatment (resulting in terminal SA removal), which significantly enhanced Cowden and RVC143 replication, but inhibited the growth of PRVC104. These observations suggest that different RVC strains may recognize terminal (PRVC104) as well as internal (Cowden and RVC143) SAs on gangliosides. Finally, several cell culture additives, such as diethylaminoethyl (DEAE)-dextran, cholesterol, and bile extract, were tested to establish if they could enhance RVC replication. We observed that only DEAE-dextran significantly enhanced RVC attachment, but it had no effect on RVC replication. Additionally, the depletion of cellular cholesterol by MβCD inhibited Cowden replication, while the restoration of the cellular cholesterol partially reversed the MβCD effects. These results suggest that cellular cholesterol plays an important role in the replication of the PRVC strain tested. Overall, our study has established a novel robust and physiologically relevant system to investigate RVC pathogenesis. We also generated novel, experimentally derived evidence regarding the role of host glycans, DEAE, and cholesterol in RVC replication, which is critical for the development of control strategies.
Pharmacophore-Model-Based Drug Repurposing for the Identification of the Potential Inhibitors Targeting the Allosteric Site in Dengue Virus NS5 RNA-Dependent RNA Polymerase
Authors: Kumar Sanjay , Bajrai Leena , Faizo Arwa , Khateb Aiah , Alkhaldy Areej , Rana Rashmi , Azhar Esam , Dwivedi Vivek
Published: August 2022

Dengue virus (DENV) is the causative agent of DENV infection. To tackle DENV infection, the development of therapeutic molecules as direct-acting antivirals (DAAs) has been demonstrated as a truly effective approach. Among various DENV drug targets, non-structural protein 5 (NS5)—a highly conserved protein among the family Flaviviridae—carries the RNA-dependent RNA polymerase (DENVRdRp) domain at the C-terminal, and its “N-pocket” allosteric site is widely considered for anti-DENV drug development. Therefore, in this study, we developed a pharmacophore model by utilising 41 known inhibitors of the DENVRdRp domain, and performed model screening against the FDA’s approved drug database for drug repurposing against DENVRdRp. Herein, drugs complying with the pharmacophore hypothesis were further processed through standard-precision (SP) and extra-precision (XP) docking scores (DSs) and binding pose refinement based on MM/GBSA binding energy (BE) calculations. This resulted in the identification of four potential potent drugs: (i) desmopressin (DS: −10.52, BE: −69.77 kcal/mol), (ii) rutin (DS: −13.43, BE: −67.06 kcal/mol), (iii) lypressin (DS: −9.84, BE: −67.65 kcal/mol), and (iv) lanreotide (DS: −8.72, BE: −64.7 kcal/mol). The selected drugs exhibited relevant interactions with the allosteric N-pocket of DENVRdRp, including priming-loop and entry-point residues (i.e., R729, R737, K800, and E802). Furthermore, 100 ns explicit-solvent molecular dynamics simulations and end-point binding free energy assessments support the considerable stability and free energy of the selected drugs in the targeted allosteric pocket of DENVRdRp. Hence, these four drugs, repurposed as potent inhibitors of the allosteric site of DENVRdRp, are recommended for further validation using experimental assays.
Properties of Adenovirus Vectors with Increased Affinity to DSG2 and the Potential Benefits of Oncolytic Approaches and Gene Therapy
Authors: Bahlmann Nora A. , Tsoukas Raphael L. , Erkens Sebastian , Wang Hongjie , Jönsson Franziska , Aydin Malik , Naumova Ella A. , Lieber André , Ehrhardt Anja , Zhang Wenli
Published: August 2022

Carcinomas are characterized by a widespread upregulation of intercellular junctions that create a barrier to immune response and drug therapy. Desmoglein 2 (DSG2) represents such a junction protein and serves as one adenovirus receptor. Importantly, the interaction between human adenovirus type 3 (Ad3) and DSG2 leads to the shedding of the binding domain followed by a decrease in the junction protein expression and transient tight junction opening. Junction opener 4 (JO-4), a small recombinant protein derived from the Ad3 fiber knob, was previously developed with a higher affinity to DSG2. JO-4 protein has been proven to enhance the effects of antibody therapy and chemotherapy and is now considered for clinical trials. However, the effect of the JO4 mutation in the context of a virus remains insufficiently studied. Therefore, we introduced the JO4 mutation to various adenoviral vectors to explore their infection properties. In the current experimental settings and investigated cell lines, the JO4-containing vectors showed no enhanced transduction compared with their parental vectors in DSG2-high cell lines. Moreover, in DSG2-low cell lines, the JO4 vectors presented a rather weakened effect. Interestingly, DSG2-negative cell line MIA PaCa-2 even showed resistance to JO4 vector infection, possibly due to the negative effect of JO4 mutation on the usage of another Ad3 receptor: CD46. Together, our observations suggest that the JO4 vectors may have an advantage to prevent CD46-mediated sequestration, thereby achieving DSG2-specific transduction.
Cellular Chondroitin Sulfate and the Mucin-like Domain of Viral Glycoprotein C Promote Diffusion of Herpes Simplex Virus 1 While Heparan Sulfate Restricts Mobility
Authors: Abidine Yara , Liu Lifeng , Wallén Oskar , Trybala Edward , Olofsson Sigvard , Bergström Tomas , Bally Marta
Published: August 2022

The diffusion of viruses at the cell membrane is essential to reach a suitable entry site and initiate subsequent internalization. Although many viruses take advantage of glycosaminoglycans (GAG) to bind to the cell surface, little is known about the dynamics of the virus–GAG interactions. Here, single-particle tracking of the initial interaction of individual herpes simplex virus 1 (HSV-1) virions reveals a heterogeneous diffusive behavior, regulated by cell-surface GAGs with two main diffusion types: confined and normal free. This study reports that different GAGs can have competing influences in mediating diffusion on the cells used here: chondroitin sulfate (CS) enhances free diffusion but hinders virus attachment to cell surfaces, while heparan sulfate (HS) promotes virus confinement and increases entry efficiency. In addition, the role that the viral mucin-like domains (MLD) of the HSV-1 glycoprotein C plays in facilitating the diffusion of the virus and accelerating virus penetration into cells is demonstrated. Together, our results shed new light on the mechanisms of GAG-regulated virus diffusion at the cell surface for optimal internalization. These findings may be extendable to other GAG-binding viruses.
Genome Similarities between Human-Derived and Mink-Derived SARS-CoV-2 Make Mink a Potential Reservoir of the Virus
Authors: Khalid Mohammad , Alshishani Anas , Al-ebini Yousef
Published: August 2022

SARS-CoV-2 has RNA as the genome, which makes the virus more prone to mutations. Occasionally, mutations help a virus to cross the species barrier. SARS-CoV-2 infections in humans and minks (Neovison vison) are examples of zoonotic spillover. Many studies on the mutational analysis of human-derived SARS-CoV-2 have been published, but insight into the mink-derived SARS-CoV-2 genome of mutations is still required. Here, we performed a mutation analysis of the mink-derived SARS-CoV-2 genome sequences. We analyzed all available full-length mink-derived SARS-CoV-2 genome sequences on GISAID (214 genome sequences from the Netherlands and 133 genome sequences from Denmark). We found a striking resemblance between human-derived and mink-derived SARS-CoV-2. Our study showed that mutation patterns in the SARS-CoV-2 genome samples from the Netherlands and Denmark were different. Out of the 201 mutations we found, only 13 mutations were shared by the Netherlands’ and Denmark’s mink-derived samples. We found that six mutations were prevalent in the mink-derived SARS-CoV-2 genomes, and these six mutations are also known to be prevalent in human-derived SARS-CoV-2 variants. Our study reveals that the G27948T mutation in SARS-CoV-2 leads to truncation of ORF8, which was also reported in human-derived SARS-CoV-2, thus indicating that the virus can replicate without the full-length ORF8. These resemblances between mink-derived and human-derived SARS-CoV-2 enable the virus to cross the species barrier and suggest mink a potential reservoir for the virus.
From Clinical Specimen to Whole Genome Sequencing of A(H3N2) Influenza Viruses: A Fast and Reliable High-Throughput Protocol
Authors: Galli Cristina , Ebranati Erika , Pellegrinelli Laura , Airoldi Martina , Veo Carla , Della Ventura Carla , Seiti Arlinda , Binda Sandro , Galli Massimo , Zehender Gianguglielmo , Pariani Elena
Published: August 2022

(1) Background: Over the last few years, there has been growing interest in the whole genome sequencing (WGS) of rapidly mutating pathogens, such as influenza viruses (IVs), which has led us to carry out in-depth studies on viral evolution in both research and diagnostic settings. We aimed at describing and determining the validity of a WGS protocol that can obtain the complete genome sequence of A(H3N2) IVs directly from clinical specimens. (2) Methods: RNA was extracted from 80 A(H3N2)-positive respiratory specimens. A one-step RT-PCR assay, based on the use of a single set of specific primers, was used to retro-transcribe and amplify the entire IV type A genome in a single reaction, thus avoiding additional enrichment approaches and host genome removal treatments. Purified DNA was quantified; genomic libraries were prepared and sequenced by using Illumina MiSeq platform. The obtained reads were evaluated for sequence quality and read-pair length. (3) Results: All of the study specimens were successfully amplified, and the purified DNA concentration proved to be suitable for NGS (at least 0.2 ng/µL). An acceptable coverage depth for all eight genes of influenza A(H3N2) virus was obtained for 90% (72/80) of the clinical samples with viral loads >105 genome copies/mL. The mean depth of sequencing ranged from 105 to 200 reads per position, with the majority of the mean depth values being above 103 reads per position. The total turnaround time per set of 20 samples was four working days, including sequence analysis. (4) Conclusions: This fast and reliable high-throughput sequencing protocol should be used for influenza surveillance and outbreak investigation.
An Economic Evaluation of the Adjuvanted Quadrivalent Influenza Vaccine Compared with Standard-Dose Quadrivalent Influenza Vaccine in the Spanish Older Adult Population
Authors: Fochesato Anna , Sottile Sara , Pugliese Andrea , Márquez-Peláez Sergio , Toro-Diaz Hector , Gani Ray , Alvarez Piedad , Ruiz-Aragón Jesús
Published: August 2022

Standard-dose quadrivalent influenza vaccines (QIV) are designed to provide protection against all four influenza strains. Adjuvanted QIV (aQIV), indicated for individuals aged 65+ years, combines MF59® adjuvant (an oil-in-water emulsion of squalene oil) with a standard dose of antigen, and is designed to produce stronger and longer immune response, especially in the elderly where immunosenescence reduces vaccine effectiveness. This study evaluated the cost-effectiveness of aQIV vs. egg-based standard-dose QIV (QIVe) in the elderly population, from the payer and societal perspective in Spain. A dynamic transmission model, which accounts for herd protection, was used to predict the number of medically attended infections in Spain. A decision tree structure was used to forecast influenza-related costs and benefits. Influenza-related probabilities of outpatient visit, hospitalization, work absenteeism, mortality, and associated utilities and costs were extracted from Spanish and European published literature. Relative vaccine effectiveness (rVE) was sourced from two different meta-analyses: the first meta-analysis was informed by laboratory-confirmed influenza studies only, resulting in a rVE = 34.6% (CI95% 2–66%) in favor of aQIV; the second meta-analysis included real world evidence influenza-related medical encounters outcomes, resulting in a rVE = 13.9% (CI95% 4.2–23.5%) in benefit of aQIV. All costs were expressed in 2021 euros. Results indicate that replacing QIVe with aQIV in the Spanish elderly population would prevent on average 43,664 influenza complicated cases, 1111 hospitalizations, and 569 deaths (with a rVE = 34.6%) or 19,104 influenza complicated cases, 486 hospitalizations, and 252 deaths (with a rVE = 13.9%). When the rVE of aQIV vs. QIVe is 34.6%, the incremental cost per quality adjusted life years (QALY) gained was €2240 from the payer; from the societal perspective, aQIV was cost saving compared with QIVe. If the rVE was 13.9%, the incremental cost per QALY was €6694 and €3936 from the payer and societal perspective, respectively. Sensitivity analyses validated the robustness of these findings. Results indicate that replacing QIVe with aQIV in the Spanish elderly population is a cost-effective strategy for the Spanish healthcare system.
COVID-19 Vaccine Effectiveness against Omicron Variant among Underage Subjects: The Veneto Region’s Experience
Authors: Cocchio Silvia , Zabeo Federico , Tremolada Giulia , Facchin Giacomo , Venturato Giovanni , Marcon Thomas , Saia Mario , Tonon Michele , Mongillo Michele , Da Re Filippo , Russo Francesca , Baldo Vincenzo
Published: August 2022

Even if most of the complications due to COVID-19 are observed in the elderly, in Italy the impact of COVID-19 among young people has not been negligible. Furthermore, their contribution to SARS-CoV-2 circulation is still unclear. These reasons have driven policy makers to involve subjects aged 5 to 17 years in the COVID-19 vaccination campaign. However, the trade-off of vaccinating this age-group should be further investigated, especially in view of the rise of new immunologically evasive variants of concern (VOCs). We used regional databases to retrospectively estimate vaccine effectiveness over time of each approved vaccination schedule among children (5–11) and adolescents (12–17). Our findings suggest that COVID-19 vaccines were highly effective and their protection levels lasted longer during a period of Delta variant predominance, whereas they offered just mild to moderate levels of protection—apparently affected by a rapid waning effect—in a period of Omicron variant predominance. Considering these results, it is plausible to evaluate a reformulation of possible future COVID-19 vaccination campaigns among underage subjects. However, effectiveness against serious complications due to COVID-19, as well as indirect benefits of underage vaccinations, should first be addressed. Furthermore, vaccine effectiveness should be kept monitored, as new VOCs may arise, but also new adapted vaccines may start being administered.
Association of Reactogenicity with Immunogenicity of the ChAdOx1 nCoV-19 Vaccine in Patients Undergoing Hemodialysis
Authors: Lin Ting-Yun , Hung Nai-Kuan , Hung Szu-Chun
Published: August 2022

The aim of our study was to determine whether local and systemic reactions following SARS-CoV-2 vaccination are predictive of immunogenicity in patients undergoing hemodialysis. We used an established questionnaire to survey 206 hemodialysis patients without prior SARS-CoV-2 infection regarding solicited local (pain, redness, and swelling) and systemic reactions (fatigue, headache, muscle and joint pain, nausea or vomiting, abdominal pain, diarrhea, and fever) within 7 days after receiving 1 dose of the ChAdOx1 nCoV-19 vaccine for SARS-CoV-2. The primary outcome was seroconversion of anti-SARS-CoV-2 IgG (≥50 AU/mL) at 28 days after vaccination. Local and systemic reactions were reported by 80 (38.8%) and 119 (57.8%) patients, respectively. A total of 138 (67.0%) patients developed an antibody response. Responders were younger, had a lower prevalence of coronary artery disease and use of immunosuppressants, and had a higher body mass index and lymphocyte count. In addition, a greater percentage of responders than non-responders reported reactogenicity. In multivariate logistic regression analyses, fever (OR 2.70 [95% CI 1.12–6.50]) and total symptom score (OR 1.33 [95% CI, 1.05–1.68], per one increase) remained strongly associated with a greater humoral response. In conclusion, higher reactogenicity may identify hemodialysis patients who are more responsive to SARS-CoV-2 vaccination.
Nested PCR Detection of Pythium sp. from Formalin-Fixed, Paraffin-Embedded Canine Tissue Sections
Authors: Elshafie Nelly O. , Hanlon Jessica , Malkawi Mays , Sayedahmed Ekramy E. , Guptill Lynn F. , Jones-Hall Yava L. , Santos Andrea P.
Published: August 2022

Pythium insidiosum is an infectious oomycete affecting dogs that develop the cutaneous or gastrointestinal form of pythiosis with a poor prognosis. If left untreated, pythiosis may be fatal. This organism is not a true fungus because its cell wall and cell membrane lack chitin and ergosterol, respectively, requiring specific treatment. Identifying the organism is challenging, as a hematoxylin and eosin (H&E) stain poorly stain the P. insidiosum hyphae and cannot be differentiated conclusively from other fungal or fungal-like organisms (such as Lagenidium sp.) morphologically. Our study aimed to develop a nested PCR to detect P. insidiosum and compare it with the traditional histopathologic detection of hyphae. Formalin-fixed, paraffin-embedded (FFPE) tissue scrolls from 26 dogs with lesions suggesting the P. insidiosum infection were assessed histologically, and DNA was extracted from the FFPE tissue sections for nested PCR. Agreement between the histologic stains, (H&E), periodic acid–Schiff (PAS), and/or Grocott methenamine silver (GMS) and the nested PCR occurred in 18/26 cases. Hyphae consistent with Pythium sp. were identified via histopathology in 57.7% of the samples, whereas the nested PCR detected P. insidiosum in 76.9% of samples, aiding in the sensitivity of the diagnosis of pythiosis in dogs. Using this combination of techniques, we report 20 canine cases of pythiosis over 18 years in Indiana and Kentucky, an unexpectedly high incidence for temperate climatic regions. Using a combination of histopathology evaluation and nested PCR is recommended to aid in the accurate diagnosis of pythiosis.
In Vision It Is Groups, Rather Than Maps, That Determine How We Perceive the World
Authors: Quinlan Philip T. , Allen Keith , Cohen Dale J.
Published: August 2022

This paper presents the results of a study that used a speeded counting task to adjudicate between two competing theories of how perceptual representations of visual objects are derived. Boolean map (BM) theory assumes that there are strict limits on conscious awareness, such that we only have serial access to features on the same dimension (e.g., red and green). This theory contrasts with views that emphasize the early grouping of features, and which assume that feature processing is interactive and underpins figure/ground segregation as a necessary precursor to object perception. To test between these theories, we report performance in a speeded counting task in which participants were asked to judge which of two shapes was more prevalent. Displays contained squares and circles that appeared in either of two colors, with color and shape distinctions either perfectly correlated (i.e., compatible) or not (i.e., incompatible). BM theory predicts no influence of the relative coincidence of color and shape on the identification of the more prevalent shape. In contrast, grouping theory predicts that performance will be better when the color/shape distinction is compatible than when it is incompatible. Our data strongly support the grouping theory predictions. We conclude that the primary constraints on how visual objects are accessed are the number and kind of groupings that are recovered, not the number of feature maps consulted.
Study on Sustainable Well Water Pumping Technology to Melt Ice in Winter for the Middle Route of the South-to-North Water Diversion Project
Authors: Zhang Yuning , Lian Jijian , Zhao Xin
Published: August 2022

In order to improve the water delivery capacity of the middle route of the South-to-North Water Diversion Project in winter, the technology of pumping well water to melt ice was previously adopted to improve the water temperature of the channel. In order to protect the local ecology and channel water quality during the process of pumping and recharging, this paper has analyzed the optimal limit to the range of groundwater level fluctuations and groundwater temperature fluctuations. The Baiquan Underground Reservoir was considered as the research object, and a three-dimensional numerical model of hydrothermal coupling was established. Correlation analyses of pumping and recharge capacity with various factors, and between temperature changes after recharging and various factors, were carried out with a view to protecting local water quality. The single well pumping and recharging scheme was optimized by genetic algorithm. The quantitative estimation formula of pumping and recharge water capacity, and the well depth, permeability coefficient, initial water level, and duration of continuous pumping and recharge, as well as the recovery water level variation formula, were established under the limitation of water level fluctuation. The quantitative relationship between horizontal maximum diameter, L, and the recharge flow rate, the continuous recharge duration, vertical maximum depth, H; and the well depth, temperature change rate, K, and the recharge water temperature, were obtained. The results showed that the permeability coefficient and soil thermal conductivity had little effect on the temperature field change. Additionally, recharge should be carried out in summer, when the temperature of recharge water is above 14.8 °C. When the number of pumping or recharging times, n, is two, the total amount of pumping or recharging during the operation period reaches its maximum. Compared with continuous operation during the operating period, this report found that the total amount of pumped water would increase by 1.1 × 106 m3, and the total amount of recharge would increase by 7 × 105 m3.
Seasonal Stratification Characteristics of Vertical Profiles and Water Quality of Lake Lugu in Southwest China
Authors: Chang Fengqin , Hou Pengfei , Wen Xinyu , Duan Lizeng , Zhang Yang , Zhang Hucai
Published: August 2022

According to the vertical section monitoring data of Lake Lugu water temperature (WT), electrical conductivity (EC), dissolved oxygen (DO), pH and chlorophyll-a (Chl-a) parameters in January (winter), April (spring), July (summer), and October (autumn) in 2015, the vertical stratification structure of WT and the null seasonality of water chemistry were analyzed. The relationship between the seasonal variation of WT stratification and the spatial and temporal distribution of EC, pH, DO and Chl-a was explored. The relationship between EC and WT was found for the epilimnion, thermocline and hypolimnion. The results of the study showed that: (1) The Lake Lugu water body shows obvious thermal stratification in spring, summer and autumn. In winter, the WT is close to isothermal condition in the vertical direction; in summer, the thermocline is located at 10–25 m water depth; while in autumn, the thermocline moves down to 20–30 m. (2) The Hypolimnion WT was maintained at 9.5 °C~10 °C, which is consistent with the annual mean temperature of Lake Lugu, indicating that the hypolimnion water column is stable and relatively constant, and reflects the annual mean temperature of the lake. The thermally stratified structure has some influence on the changes of EC, DO, pH and Chl-a, resulting in the obvious stratification of EC, DO and pH in the water body. (3) Especially in summer, when the temperature increased, the thermal stratification phenomenon was significant, and DO and pH peaked in thermocline, with a decreasing trend from the peak upward and downward, and the hypolimnion was in an anoxic state and the pH value was small. Although chlorophyll a remained low below thermocline and was not high overall, there was a sudden increase in the surface layer, which should be highly warned to prevent a large algal bloom or even a localized outbreak in Lake Lugu. (4) There is a simple linear function between EC and WT in both vertical section and Epilimnion, thermocline and hypolimnion, which proves that Lake Lugu is still influenced by natural climate and maintains natural water state, and is a typical warm single mixed type of lake. (5) It is suggested to strengthen water quality monitoring, grasp its change pattern and influence factors, and take scientific measures to prevent huge pressure on the closed ecological environment of Lake Lugu, and provide scientific basis for the protection of high-quality freshwater lakes in the plateau.
Study of the Water Environment Risk Assessment of the Upper Reaches of the Baiyangdian Lake, China
Authors: Guan Xiaoyan , Ren Xiaoqiang , Tao Yuan , Chang Xiaomin , Li Bing
Published: August 2022

The risk assessment of water environments provides important references for water environment risk management. In this paper, the water environment risk of the upper rivers of the Baiyangdian Lake is assessed, considering both cumulative and sudden environmental risk. For the cumulative environmental risk assessment of the rivers, the characteristics of pollution transmissibility and accumulation in rivers was considered firstly. Furthermore, suggestions for the control of water environment pollution in the Baiyangdian Basin are given. The results indicate that the cumulative water environment risks of the Xiaoyi River—Dingzhou County, Xiaoyi River—Anguo County, Xiaoyi River—Boye County, and Xiaoyi River—Li County are high. The amount of fertilizer applied per unit of cultivated area, water quality, rate of water quality above the standard in water function zoning, and the ratio of environmental investment to gross domestic product (GDP) are important factors influencing the cumulative water environment risk. For sudden water environment assessments, the Xiaoyi River—Boye County is high. In the future, reducing the intensity of fertilizer application, strengthening the water quality control of the rivers, as well as upgrading the industry, should be carried out to protect the water environment in the Baiyangdian Basin.
Where You Drink Water: An Assessment of the Tennessee, USA Public Water Supply
Authors: Ding Ke Jack , Hornberger George M. , Hill Elaine L. , McDonald Yolanda J.
Published: August 2022

Monitoring drinking water quality is essential to protect people’s health and wellbeing. In the United States, the Safe Drinking Water Information System (SDWIS) database records the occurrence of a drinking water violation regulation in public water systems. A notable shortcoming of SDWIS is the lack of the contaminant concentration level about the allowable maximum contaminant threshold. In this study, we take advantage of both the SDWIS violation database and the contaminants sampling database at the state level to examine the drinking water quality of all kinds of drinking water systems in detail. We obtained sampling data (i.e., the concentration level of contaminants) of public water systems (PWSs) in Tennessee and explored the statistical distribution of contaminant concentration data in relation to the enforceable maximum regulatory contaminant level). We use both SDWIS violation records and actual concentrations of contaminants from the sampling data to study the factors that influence the drinking water quality of PWSs. We find that different types of violations were more frequent in (1) specific geological regions, (2) counties with PWSs that serve a larger population (10,000 to 100,000 people), and (3) places with abundant surface water, such as near a lake or major river. Additionally, the distribution of measured concentrations for many contaminants was not smooth but was punctuated by discontinuities at selected levels, such as at 50% of the maximum contaminant level. Such anomalies in the sampling data do not indicate violations, but more investigation is needed to determine the reasons behind the punctuated changes.
Factors That Affect Hydropower Flexibility
Authors: Thapa Sumi , Magee Timothy , Zagona Edith
Published: August 2022

Flexibility in power systems is the potential to increase or decrease generation relative to scheduled generation or when most valuable. Increased penetration of variable renewable energy sources such as wind and solar increases the need for flexibility. Conventional hydropower plants are an important source of flexibility due to their ability to shut down and start generation units at short notice. However, there are not metrics or standards for hydropower managers to measure or quantify the potential flexibility of their systems. This novel study identifies key hydro system characteristics—physical and operational factors as well as the power markets—that, in our experience with real hydro systems, affect flexibility. A realistic but fictional system is analyzed that includes operating policies, deployment of reserves, physical aspects such as size of reservoirs, network configuration and power markets. The system is first modeled per “business as usual” operating rules to maximize total economic value of generation. The flexibility analysis measures the generation that can be increased or decreased in a single day by either maximizing the total on-peak generation in the upward direction or minimizing the total nadir generation in the downward direction. Results show the effects of each factor on both upward and downward flexibility.
Integrated Evaluation of Rivers Based upon the River Happiness Index (RHI): Happy Rivers in China
Authors: Ju Qianqian , Liu Changshun , Jiang Shan
Published: August 2022

How to better harmonize the relationship between humans and rivers is a global issue of widespread concern at home and abroad, and science-based and integrated evaluation of rivers themselves is crucial to river management. Based on Maslow’s hierarchy of needs and according to the World Happiness Report and the 2030 Agenda for Sustainable Development, this paper argues that a happy river is a river that can maintain its own health, support high-quality economic and social development in the river basin and the region, reflect harmony between humans and water, and give people in the river basin a high sense of security and the ability to gain and satisfaction. This paper also analyzes happy rivers at five levels, including water security, water resources, water environment, water ecology, and water culture, and develops the River Happiness Index (RHI) and its indicator system, as well as assesses the overall river happiness in China’s 10 first-grade water resource zones. The results show that China’s RHI is at a medium level, with flood control capacity at a near-good level. On the grounds of the RHI evaluation results, the paper puts forward targeted measures for river basin governance, and provides a systematic solution to national river protection and governance.
Gated Attention Recurrent Neural Network: A Deeping Learning Approach for Radar-Based Precipitation Nowcasting
Authors: Wu Guanchen , Chen Wenhui , Jung Hoekyung
Published: August 2022

Precipitation nowcasting predicts the future rainfall intensity in local areas in a brief time that impacts directly on human life. In this paper, we express the precipitation nowcasting as a spatiotemporal sequence prediction problem. Predictive learning for a spatiotemporal sequence aims to construct a model of natural spatiotemporal processes to predict the future frames based on historical frames. The spatiotemporal process is an abstraction of some of the spatial things in nature that change with time, and they usually do not change very dramatically. To simplify the model and facilitate the training, we considered that the spatiotemporal process satisfies the generalized Markov properties. The natural spatiotemporal processes are nonlinear and non-stationary in many aspects. The processes are not satisfied with the first-order Markov properties when making predictions, such as the nonlinear movement, expansion, dissipation, and intensity enhancement of echoes. To describe such complex spatiotemporal variations, higher-order Markov models need to be used for the modeling. However, many of the previous models for spatiotemporal prediction constructed were based on first-order Markov properties, losing information on the higher-order variations. Thus, we propose a recurrent neural network which satisfies the multi-order Markov properties to create more accurate spatiotemporal predictions. In this network, the core component is the memory cell structure of the gated attention mechanism, which combines the current input information, extracts the historical state that best matches the existing input from the historical multi-period memory information, and then predicts the future. Through this principle of the gated attention, we could extract the historical state information that is richer and deeper to predict the future and more accurately describe the changing characteristics of motion. The experiments show that our GARNN network captures the spatiotemporal characteristics better and obtains excellent results in the precipitation forecasting with radar echoes.
Characteristic Analysis of the Spatio-Temporal Distribution of Key Variables of the Soil Freeze–Thaw Processes over Heilongjiang Province, China
Authors: Song Chengjie , Dai Changlei , Wang Chuang , Yu Miao , Gao Yaqi , Tu Weiming
Published: August 2022

The soil freeze–thaw phenomenon is one of the most outstanding characteristics of the soil in Heilongjiang Province. Quantitative analysis of the characteristics of changes in key variables of the soil freeze–thaw processes is of great scientific importance for understanding climate change, as well as ecological and hydrological processes. Based on the daily surface temperature and air temperature data in Heilongjiang Province for the past 50 years, the spatial–temporal distribution characteristics of key variables and their correlations with air temperature and latitude in the freeze–thaw process of soil were analyzed using linear regression, the Mann–Kendall test, the local thin disk smooth spline function interpolation method, and correlation analysis; additionally, the spatial–temporal distribution of key variables and the changes in the surface temperature during the freeze–thaw process are discussed under different vegetation types. The results show that there is a trend of delayed freezing and early melting of key variables of the soil freeze–thaw process from north to south. From 1971 to 2019 a, the freezing start date (FSD) was delayed at a rate of 1.66 d/10 a, the freezing end date (FED) advanced at a rate of 3.17 d/10 a, and the freezing days (FD) were shortened at a rate of 4.79 d/10 a; with each 1 °C increase in temperature, the FSD was delayed by about 1.6 d, the FED was advanced by about 3 d, and the FD was shortened by about 4.6 d; with each 1° increase in latitude, the FSD was delayed by about 2.6 d, the FED was advanced by about 2.8 d, and the FD was shortened by about 5.6 d. The spatial variation in key variables of the soil freeze–thaw process under the same vegetation cover was closely related to latitude and altitude, where the lower the latitude and altitude, the more obvious the variation trend; among them, the interannual variation trend of key variables of soil freeze–thaw under meadow cover was the most obvious, which varied by 9.65, 16.86, and 26.51 d, respectively. In addition, the trends of ground temperature under different vegetation types were generally consistent, with the longest period of unstable freeze–thaw and the shortest period of stable freeze in coniferous forests, compared to the shortest period of unstable freeze–thaw and the longest period of stable freeze in meadows. The results of the study are important for our understanding of soil freeze–thaw processes and changes in Heilongjiang Province, as well as the evolution of high-latitude permafrost; they also promote further exploration of the impact of soil freeze–thaw on agricultural production and climate change.
Treatment and Effective Removal of Metal Fine Particles from Waste Cutting Fluids by Flotation via Microbubbles and Skimming
Authors: Fukami Kimio , Ogata Namiko , Yamamoto Kenji , Kawamura Kazuki , Mitani Iwao , Sakamoto Masaoki
Published: August 2022

Cutting fluids (CFs) are chemical liquids or aqueous emulsions of mineral (or synthetic) oil widely used in metal-machining processes. They contain toxic organic compounds and petroleum products, and spent CFs contain numerous small metal particles derived from the processing of metal workpieces. The iron fine particles (IFPs) in CFs can diminish the quality and precision of machine products. Machining industries purchase large amounts of CFs, which they must treat appropriately and from which they must remove the IFPs; therefore, cost-effective ways to treat spent CFs are needed. In this study, we evaluated the effectiveness of collecting and separating the IFPs and treating organic matter in spent CFs using microbubbles (MiBs). We found that numerous IFPs with sizes of ~1 μm were suspended in spent CFs and that they could be very effectively removed by bubbling with MiBs and skimming the surface of the CFs. The lifetime of the CFs could be doubled via this treatment. The cost for treating spent CFs using MiBs was 12% lower than the cost of traditional treatment. These results strongly suggest that bubbling with MiBs is a cost-effective and eco-friendly way to treat spent CFs.
Pedestrian Crossing Intention Prediction Method Based on Multi-Feature Fusion
Authors: Ma Jun , Rong Wenhui
Published: August 2022

Pedestrians are important traffic participants and prediction of pedestrian crossing intention can help reduce pedestrian–vehicle collisions. For the problem of predicting an individual pedestrian’s action where there is crossing potential, a pedestrian crossing intention prediction method that considers multi-feature fusion is proposed in this study, which integrates information affecting pedestrians’ actions, such as pedestrian action and traffic environment. This study is based on the BPI dataset for training and validation, and the test results show that the model has good data fitting and generalization ability; the test set has good prediction accuracy of 89.5% in the model, with an AUC of 0.992. In the specific scenario, the method proposed in this study can predict pedestrian crossing intention when the longitudinal relative distance between a pedestrian and vehicle is about 20 m and about 0.6 s before the pedestrian crossing, which can provide useful information for decision making in intelligent vehicles.
“I Didn’t Have the Language”: Young People Learning to Challenge Gender-Based Violence through Consumption of Social Media
Authors: Molnar Lena Ida
Published: August 2022

In recent years, young people in Australia and abroad have taken to social media to express their concerns about the violent behaviour of their peers, and to share content that challenges the causes of gender-based and interpersonal violence. From launching policy-changing petitions to responding to and engaging with online campaigns, young people are pushing action and momentum from generational changes in feminist movements. Young people have their own contexts and influences that affect understandings and responses to gendered inequality and violence. This paper discusses the findings of nine focus groups with 32 young people who share content online about preventing gender-based violence, exploring their perceptions on their reasonings for using these tools and how they came to assumptions about gender inequality. It explores the contexts that young people in Australia draw upon to challenge existing gender inequalities and their reasonings for using social media to share ideas about preventing violence with others. The findings of this paper, thus, have implications for how young people are engaged in the primary prevention of gender-based violence, suggesting better use for social-media-campaign content engagement.