bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of Communication Performance of Drones Used for Autonomous Car Track Tests
Authors: Yildiz Melih , Bilgiç Burcu , Kale Utku , Rohács Dániel
Published: May 2021

Autonomous Vehicles (AVs) represent an emerging and disruptive technology that provides a great opportunity for future transport not only to have a positive social and environmental impact but also traffic safety. AV use in daily life has been extensively studied in the literature in various dimensions, however; it is time for AVs to go further which is another technological aspect of communication. Vehicle-to-Vehicle (V2V) technology is an emerging issue that is expected to be a mutual part of AVs and transportation safety in the near future. V2V is widely discussed by its deployment possibilities not only by means of communication, even to be used as an energy transfer medium. ZalaZONE Proving Ground is a 265-hectare high-tech test track for conventional, electric as well as connected, assisted, and automated vehicles. This paper investigates the use of drones for tracking the cars on the test track. The drones are planned to work as an uplink for the data collected by the onboard sensors of the car. The car is expected to communicate with the drone which is flying in coordination. For the communication 868 MHz is selected to be used between the car and the drone. The test is performed to simulate different flight altitudes of drones. The signal strength of the communication is analyzed, and a model is developed which can be used for the future planning of the test track applications.
Dynamics of Fuzzy-Rough Cognitive Networks
Authors: Harmati István Á.
Published: May 2021

Fuzzy-rough cognitive networks (FRCNs) are interpretable recurrent neural networks, primarily designed for solving classification problems. Their structure is simple and transparent, while the performance is comparable to the well-known black-box classifiers. Although there are many applications on fuzzy cognitive maps and recently for FRCNS, only a very limited number of studies discuss the theoretical issues of these models. In this paper, we examine the behaviour of FRCNs viewing them as discrete dynamical systems. It will be shown that their mathematical properties highly depend on the size of the network, i.e., there are structural differences between the long-term behaviour of FRCN models of different size, which may influence the performance of these modelling tools.
Theoretical Basis of Quantum-Mechanical Modeling of Functional Nanostructures
Authors: Fedotov Aleksey , Vakhrushev Alexander , Severyukhina Olesya , Sidorenko Anatolie , Savva Yuri , Klenov Nikolay , Soloviev Igor
Published: May 2021

The paper presents an analytical review of theoretical methods for modeling functional nanostructures. The main evolutionary changes in the approaches of quantum-mechanical modeling are described. The foundations of the first-principal theory are considered, including the stationery and time-dependent Schrödinger equations, wave functions, the form of writing energy operators, and the principles of solving equations. The idea and specifics of describing the motion and interaction of nuclei and electrons in the framework of the theory of the electron density functional are presented. Common approximations and approaches in the methods of quantum mechanics are presented, including the Born–Oppenheimer approximation, the Hartree–Fock approximation, the Thomas–Fermi theory, the Hohenberg–Kohn theorems, and the Kohn–Sham formalism. Various options for describing the exchange–correlation energy in the theory of the electron density functional are considered, such as the local density approximation, generalized and meta-generalized gradient approximations, and hybridization of the generalized gradient method. The development of methods of quantum mechanics to quantum molecular dynamics or the dynamics of Car–Parrinello is shown. The basic idea of combining classical molecular modeling with calculations of the electronic structure, which is reflected in the potentials of the embedded atom, is described.
Sodium Butyrate More Effectively Mitigates the Negative Effects of High-Concentrate Diet in Dairy Cows than Sodium β-Hydroxybutyrate via Reducing Free Bacterial Cell Wall Components in Rumen Fluid and Plasma
Authors: Wu Yongjiang , Sun Yawang , Zhang Ruiming , He Tianle , Huang Guohao , Tian Ke , Liu Junhui , Chen Juncai , Dong Guozhong
Published: May 2021

The present study was aimed at investigating the effects of sodium butyrate and sodium β-hydroxybutyrate on lactation and health of dairy cows fed a high-concentrate (HC) diet. Eighty mid-lactation dairy cows with an average milk yield of 33.75 ± 5.22 kg/d were randomly allocated to four groups (n = 20 per group) and were fed either a low-concentrate (LC) diet, a HC diet, the HC diet with 1% sodium butyrate (HCSB), or the HC diet with 1% sodium β-hydroxybutyrate (HCHB). The feeding trial lasted for 7 weeks, with a 2-week adaptation period and a 5-week measurement period, and the trial started from 96 ± 13 d in milk. Sodium butyrate supplementation delayed the decline in milk production and improved milk synthesis efficiency and milk fat content. Additionally, it decreased the proinflammatory cytokines and acute phase proteins (APPs) in plasma, the leucocytes in blood, the somatic cell count (SCC) in milk, and the gene expression of pattern recognition receptors (PRRs) and proinflammatory cytokines in the mammary gland, due to decreasing the contents of bacterial cell wall components (lipopolysaccharide, LPS; peptidoglycan, PGN; and lipoteichoic acid, LTA) in the rumen and plasma, compared with the HC diet. Sodium β-hydroxybutyrate supplementation also improved milk yield, milk synthesis efficiency and milk fat content and partially reduced the adverse effects caused by the HC diet, but it had no effect on decreasing bacterial cell wall components in the rumen and plasma, compared with the HC diet. Collectively, both sodium butyrate and sodium β-hydroxybutyrate mitigated the negative effects of HC diet on lactation and health of dairy cows, with sodium butyrate being more effective than sodium β-hydroxybutyrate.
N58A Exerts Analgesic Effect on Trigeminal Neuralgia by Regulating the MAPK Pathway and Tetrodotoxin-Resistant Sodium Channel
Authors: Li Chun-Li , Yang Ran , Sun Yang , Feng Yuan , Song Yong-Bo
Published: May 2021

The primary studies have shown that scorpion analgesic peptide N58A has a significant effect on voltage-gated sodium channels (VGSCs) and plays an important role in neuropathic pain. The purpose of this study was to investigate the analgesic effect of N58A on trigeminal neuralgia (TN) and its possible mechanism. The results showed that N58A could significantly increase the threshold of mechanical pain and thermal pain and inhibit the spontaneous asymmetric scratching behavior of rats. Western blotting results showed that N58A could significantly reduce the protein phosphorylation level of ERK1/2, P38, JNK, and ERK5/CREB pathways and the expression of Nav1.8 and Nav1.9 proteins in a dose-dependent manner. The changes in current and kinetic characteristics of Nav1.8 and Nav1.9 channels in TG neurons were detected by the whole-cell patch clamp technique. The results showed that N58A significantly decreased the current density of Nav1.8 and Nav1.9 in model rats, and shifted the activation curve to hyperpolarization and the inactivation curve to depolarization. In conclusion, the analgesic effect of N58A on the chronic constriction injury of the infraorbital (IoN-CCI) model rats may be closely related to the regulation of the MAPK pathway and Nav1.8 and Nav1.9 sodium channels.
Renormalizability of Alternative Theories of Gravity: Differences between Power Counting and Entropy Argument
Authors: Bajardi Francesco , Bascone Francesco , Capozziello Salvatore
Published: May 2021

It is well known that General Relativity cannot be considered under the standard of a perturbatively renormalizable quantum field theory, but asymptotic safety is taken into account as a possibility for the formulation of gravity as a non-perturbative renormalizable theory. Recently, the entropy argument has however stepped into the discussion claiming for a “no-go” to the asymptotic safety argument. In this paper, we present simple counter-examples, considering alternative theories of gravity, to the entropy argument as further indications, among others, on the possible flows in the assumptions on which the latter is based. We considered different theories, namely curvature-based extensions of General Relativity as f(R), f(G), extensions of teleparallel gravity as f(T), and Horava–Lifshitz gravity, working out the explicit spherically symmetric solutions in order to make a comparison between power counting and the entropy argument. Even in these cases, inconsistencies were found.
Diagnostic Performance of Ag-RDTs and NAAT for SARS-CoV2 Identification in Symptomatic Patients in Catalonia
Authors: Basile Luca , Guadalupe-Fernández Víctor , Valdivia Guijarro Manuel , Martinez Mateo Ana , Ciruela Navas Pilar , Mendioroz Peña Jacobo ,   the Epidemiological Surveillance Network of Catalonia
Published: May 2021

The use of rapid antigenic tests (Ag-RDTs) to diagnose a SARS-CoV-2 infection has become a common practice recently. This study aimed to evaluate performance of Abbott PanbioTM Ag-RDTs with regard to nucleic acid amplification testing (NAAT) in the early stages of the disease. A cohort of 149,026 infected symptomatic patients, reported in Catalonia from November 2020 to January 2021, was selected. The positivity rates of the two tests were compared with respect to the dates of symptom onset. Ag-RDTs presented positivity rates of 84% in the transmission phases of the disease and 31% in the pre-symptomatic period, compared to 93% and 91%, respectively, for NAAT. The detection of many false negatives with Ag-RDTs during the pre-symptomatic period demonstrates the risk of virus dissemination with this diagnostic technique if used outside the symptomatic period.
Mechanism of Cross-Species Transmission, Adaptive Evolution and Pathogenesis of Hepatitis E Virus
Authors: Primadharsini Putu Prathiwi , Nagashima Shigeo , Okamoto Hiroaki
Published: May 2021

Hepatitis E virus (HEV) is the leading cause of acute hepatitis worldwide. While the transmission in developing countries is dominated by fecal-oral route via drinking contaminated water, the zoonotic transmission is the major route of HEV infection in industrialized countries. The discovery of new HEV strains in a growing number of animal species poses a risk to zoonotic infection. However, the exact mechanism and the determinant factors of zoonotic infection are not completely understood. This review will discuss the current knowledge on the mechanism of cross-species transmission of HEV infection, including viral determinants, such as the open reading frames (ORFs), codon usage and adaptive evolution, as well as host determinants, such as host cellular factors and the host immune status, which possibly play pivotal roles during this event. The pathogenesis of hepatitis E infection will be briefly discussed, including the special forms of this disease, including extrahepatic manifestations, chronic infection, and fulminant hepatitis in pregnant women.
Prognostic Markers and Driver Genes and Options for Targeted Therapy in Human-Papillomavirus-Positive Tonsillar and Base-of-Tongue Squamous Cell Carcinoma
Authors: Näsman Anders , Holzhauser Stefan , Kostopoulou Ourania N. , Zupancic Mark , Ährlund-Richter Andreas , Du Juan , Dalianis Tina
Published: May 2021

The incidence of Human-papillomavirus-positive (HPV+) tonsillar and base-of-tongue squamous cell carcinoma (TSCC and BOTSCC, respectively) is increasing epidemically, but they have better prognosis than equivalent HPV-negative (HPV−) cancers, with roughly 80% vs. 50% 3-year disease-free survival, respectively. The majority of HPV+ TSCC and BOTSCC patients therefore most likely do not require the intensified chemoradiotherapy given today to head and neck cancer patients and would with de-escalated therapy avoid several severe side effects. Moreover, for those with poor prognosis, survival has not improved, so better-tailored alternatives are urgently needed. In line with refined personalized medicine, recent studies have focused on identifying predictive markers and driver cancer genes useful for better stratifying patient treatment as well as for targeted therapy. This review presents some of these endeavors and briefly describes some recent experimental progress and some clinical trials with targeted therapy.
Structural Insights into the Interaction of Filovirus Glycoproteins with the Endosomal Receptor Niemann-Pick C1: A Computational Study
Authors: Igarashi Manabu , Hirokawa Takatsugu , Takadate Yoshihiro , Takada Ayato
Published: May 2021

Filoviruses, including marburgviruses and ebolaviruses, have a single transmembrane glycoprotein (GP) that facilitates their entry into cells. During entry, GP needs to be cleaved by host proteases to expose the receptor-binding site that binds to the endosomal receptor Niemann-Pick C1 (NPC1) protein. The crystal structure analysis of the cleaved GP (GPcl) of Ebola virus (EBOV) in complex with human NPC1 has demonstrated that NPC1 has two protruding loops (loops 1 and 2), which engage a hydrophobic pocket on the head of EBOV GPcl. However, the molecular interactions between NPC1 and the GPcl of other filoviruses remain unexplored. In the present study, we performed molecular modeling and molecular dynamics simulations of NPC1 complexed with GPcls of two ebolaviruses, EBOV and Sudan virus (SUDV), and one marburgvirus, Ravn virus (RAVV). Similar binding structures were observed in the GPcl–NPC1 complexes of EBOV and SUDV, which differed from that of RAVV. Specifically, in the RAVV GPcl–NPC1 complex, the tip of loop 2 was closer to the pocket edge comprising residues at positions 79–88 of GPcl; the root of loop 1 was predicted to interact with P116 and Q144 of GPcl. Furthermore, in the SUDV GPcl–NPC1 complex, the tip of loop 2 was slightly closer to the residue at position 141 than those in the EBOV and RAVV GPcl–NPC1 complexes. These structural differences may affect the size and/or shape of the receptor-binding pocket of GPcl. Our structural models could provide useful information for improving our understanding the differences in host preference among filoviruses as well as contributing to structure-based drug design.
Development and Validation of Confirmatory Foot-and-Mouth Disease Virus Antibody ELISAs to Identify Infected Animals in Vaccinated Populations
Authors: Tewari Anuj , Ambrose Helen , Parekh Krupali , Inoue Toru , Guitian Javier , Nardo Antonello Di , Paton David James , Parida Satya
Published: May 2021

In foot-and-mouth disease (FMD)-endemic countries, vaccination is commonly used to control the disease, whilst in FMD-free countries, vaccination is considered as an option, in addition to culling the infected and in contact animals. FMD vaccines are mainly comprised of inactivated virions and stimulate protective antibodies to virus structural proteins. In contrast, infection with FMD virus leads to virus replication and additional antibody responses to viral nonstructural proteins (NSP). Therefore, antibodies against NSPs are used to differentiate infection in vaccinated animals (DIVA), in order to estimate the prevalence of infection or its absence. Another advantage of NSP antibody tests is that they detect FMD infection in the field, irrespective of the serotypes of virus in circulation. In cattle, the NSP tests that target the 3ABC polyprotein provides the highest sensitivity, detecting up to 90% of vaccinated animals that become carriers after exposure to infection, with a specificity of around 99%. Due to insufficient diagnostic sensitivity and specificity, detection of a low level of infection is difficult at the population level with a high degree of confidence. The low level of non-specific responses can be overcome by retesting samples scored positive using a second confirmatory test, which should have at least comparable sensitivity to the first test. In this study, six in-house tests were developed incorporating different NSP antigens, and validated using bovine sera from naïve animals, field cases and experimentally vaccinated and/or infected animals. In addition, two (short and long incubation) new commercial NSP tests based on 3ABC competitive blocking ELISAs (ID Screen® FMD NSP Competition, IDvet, France) were validated in this study. The two commercial ELISAs had very similar sensitivities and specificities that were not improved by lengthening the incubation period. Several of the new in-house tests had performance characteristics that were nearly as good as the commercial ELISAs. Finally, the in-house tests were evaluated for use as confirmatory tests following screening with the PrioCHECK® and ID Screen® FMDV NS commercial kits, to assess the diagnostic performance produced by a multiple testing strategy. The in-house tests could be used in series (to confirm) or in parallel (to augment) with the PrioCHECK® and IDvet® FMDV NS commercial kits, in order to improve either the specificity or sensitivity of the overall test system, although this comes at the cost of a reduction in the counterpart (sensitivity/specificity) parameter.
Comparison of the Virome of Quarantined Sugarcane Varieties and the Virome of Grasses Growing near the Quarantine Station
Authors: Daugrois Jean H. , Filloux Denis , Julian Charlotte , Claude Lisa , Ferdinand Romain , Fernandez Emmanuel , Fontes Hugo , Rott Philippe C. , Roumagnac Philippe
Published: May 2021

Visacane is a sugarcane quarantine station located in the South of France, far away from sugarcane growing areas. Visacane imports up to 100 sugarcane varieties per year, using safe control and confinement measures of plants and their wastes to prevent any risk of pathogen spread outside of the facilities. Viruses hosted by the imported material are either known or unknown to cause disease in cultivated sugarcane. Poaceae viruses occurring in plants surrounding the quarantine glasshouse are currently unknown. These viruses could be considered as a source of new sugarcane infections and potentially cause new sugarcane diseases in cases of confinement barrier failure. The aim of this study was to compare the plant virome inside and outside of the quarantine station to identify potential confinement failures and risks of cross infections. Leaves from quarantined sugarcane varieties and from wild Poaceae growing near the quarantine were collected and processed by a metagenomics approach based on virion-associated nucleic acids extraction and library preparation for Illumina sequencing. While viruses belonging to the same virus genus or family were identified in the sugarcane quarantine and its surroundings, no virus species was detected in both environments. Based on the data obtained in this study, no virus movement between quarantined sugarcane and nearby grassland has occurred so far, and the confinement procedures of Visacane appear to be properly implemented.
Advances in Feline Viruses and Viral Diseases
Authors: Beatty Julia A. , Hartmann Katrin
Published: May 2021

Viral diseases play a very important role in feline medicine, and research on feline viruses and viral diseases is a well-established field that helps to safeguard the health of domestic cats and non-domestic felids, many of which are endangered [...]
M448R and MGF505-7R: Two African Swine Fever Virus Antigens Commonly Recognized by ASFV-Specific T-Cells and with Protective Potential
Authors: Bosch-Camós Laia , López Elisabet , Collado Javier , Navas María J. , Blanco-Fuertes Miguel , Pina-Pedrero Sonia , Accensi Francesc , Salas Maria Luisa , Mundt Egbert , Nikolin Veljko , Rodríguez Fernando
Published: May 2021

African swine fever (ASF) is today′s number one threat for the global swine industry. Neither commercial vaccine nor treatment is available against ASF and, thus far, only live attenuated viruses (LAV) have provided robust protection against lethal ASF virus (ASFV) challenge infections. Identification of ASFV proteins inducing protective immune responses is one of the major challenges to develop safer and efficient subunit vaccines. Immunopeptidomic studies recently performed in our laboratory allowed identifying ASFV antigens recognized by ASFV-specific CD8+ T-cells. Here, we used data from the SLAI-peptide repertoire presented by a single set of ASFV-infected porcine alveolar macrophages to generate a complex DNA vaccine composed by 15 plasmids encoding the individual peptide-bearing ORFs. DNA vaccine priming improved the protection afforded by a suboptimal dose of the BA71ΔCD2 LAV given as booster vaccination, against Georgia2007/1 lethal challenge. Interestingly, M448R was the only protein promiscuously recognized by the induced ASFV-specific T-cells. Furthermore, priming pigs with DNA plasmids encoding M488R and MGF505-7R, a CD8+ T-cell antigen previously described, confirmed these two proteins as T-cell antigens with protective potential. These studies might be useful to pave the road for designing safe and more efficient vaccine formulations in the future.
Epigenetic Mechanisms of HIV-1 Persistence
Authors: Verdikt Roxane , Hernalsteens Olivier , Van Lint Carine
Published: May 2021

Eradicating HIV-1 in infected individuals will not be possible without addressing the persistence of the virus in its multiple reservoirs. In this context, the molecular characterization of HIV-1 persistence is key for the development of rationalized therapeutic interventions. HIV-1 gene expression relies on the redundant and cooperative recruitment of cellular epigenetic machineries to cis-regulatory proviral regions. Furthermore, the complex repertoire of HIV-1 repression mechanisms varies depending on the nature of the viral reservoir, although, so far, few studies have addressed the specific regulatory mechanisms of HIV-1 persistence in other reservoirs than the well-studied latently infected CD4+ T cells. Here, we present an exhaustive and updated picture of the heterochromatinization of the HIV-1 promoter in its different reservoirs. We highlight the complexity, heterogeneity and dynamics of the epigenetic mechanisms of HIV-1 persistence, while discussing the importance of further understanding HIV-1 gene regulation for the rational design of novel HIV-1 cure strategies.
Knowledge, Attitudes and Perceptions of COVID-19 Vaccination among Healthcare Workers of an Inner-City Hospital in New York
Authors: Ciardi Federico , Menon Vidya , Jensen Jamie L. , Shariff Masood A , Pillai Anjana , Venugopal Usha , Kasubhai Moiz , Dimitrov Vihren , Kanna Balavenkatesh , Poole Brian D.
Published: May 2021

Introduction: New York City is one of the areas most affected by the COVID-19 pandemic in the United States. Healthcare workers are among those at high risk of contracting the virus, and a vital source of information and trust in vaccines to the community. Methods: This study was conducted about attitudes towards COVID-19 vaccination among healthcare workers at a public hospital in New York City during the beginning of COVID-19 vaccination. 428 hospital employees responded. Results: Several factors were significantly associated with vaccine attitudes, including demographics such as gender (p = 0.002), age (p = 0.005), race (p < 0.001) and home location (p < 0.001), role within the hospital (p < 0.001), knowledge about the virus (p < 0.001) and confidence in and expectations about personal protective equipment and behaviors (p < 0.001). Structural equation modeling revealed that the most predictive factors were prior vaccine attitudes and concern with the speed of testing and approval of the vaccines (p < 0.001). Multivariate analysis reinforced these, while also identifying perceived personal risk as significant (p = 0.033). Conclusions: Several modifiable factors that reflect confidence in science, scientific knowledge, personal risk perception, experience and medical authority are correlated with vaccine attitudes, indicating that a holistic educational approach to improve trust in science is likely to be effective in long-term reduction in vaccine hesitancy.
Monitoring of Organochlorine Pesticide and Polychlorinated Biphenyl Residues in Common Swifts (Apus apus) in the Region of Hannover, Lower Saxony, Germany
Authors: Tiyawattanaroj Warakorn , Witte Stefan , Fehr Michael , Legler Marko
Published: May 2021

The use of pesticides is associated with the decline of several avian species. In this study, we monitored the organochlorine contaminants in common swifts (Apus apus) in the years 2016 to 2018. These long-distance migrants breed in Europe and winter in Africa. Their only feeding source is aerial plankton. Pooled organ samples of 42 adult and 40 juvenile swifts were tested with the multi-residue method by gas chromatography-mass spectrometry (GC-TOF/MS). Predominantly, 4,4′-DDE, dieldrin, hexachlorobenzene (HCB), lindane and polychlorinated biphenyls (PCBs) were found in most of these common swifts. Only 4,4′-DDE (adult: 83 ± 70 μg/kg, juvenile: 17 ± 39 μg/kg) and dieldrin (adult: 2 ± 3 μg/kg, juvenile: 0.3 ± 1 μg/kg) concentrations were significantly different between adult and juvenile birds. All detected concentrations in our study were far lower than the previously recorded pesticide concentrations of common swifts in Italy and those which are known to cause toxicity and death in birds.
Development of a Novel Damage Detection Framework for Truss Railway Bridges Using Operational Acceleration and Strain Response
Authors: Azim Md Riasat , Gül Mustafa
Published: May 2021

Railway bridges are an integral part of any railway communication network. As more and more railway bridges are showing signs of deterioration due to various natural and artificial causes, it is becoming increasingly imperative to develop effective health monitoring strategies specifically tailored to railway bridges. This paper presents a new damage detection framework for element level damage identification, for railway truss bridges, that combines the analysis of acceleration and strain responses. For this research, operational acceleration and strain time-history responses are obtained in response to the passage of trains. The acceleration response is analyzed through a sensor-clustering-based time-series analysis method and damage features are investigated in terms of structural nodes from the truss bridge. The strain data is analyzed through principal component analysis and provides information on damage from instrumented truss elements. A new damage index is developed by formulating a strategy to combine the damage features obtained individually from both acceleration and strain analysis. The proposed method is validated through a numerical study by utilizing a finite element model of a railway truss bridge. It is shown that while both methods individually can provide information on damage location, and severity, the new framework helps to provide substantially improved damage localization and can overcome the limitations of individual analysis.
Streamflow Changes in the Headwater Area of Yellow River, NE Qinghai-Tibet Plateau during 1955–2040 and Their Implications
Authors: Ma Qiang , Dai Changlei , Jin Huijun , Liang Sihai , Bense Victor , Lan Yongchao , Marchenko Sergey , Wang Chuang
Published: May 2021

Human activities have substantially altered present-day flow regimes. The Headwater Area of the Yellow River (HAYR, above Huanghe’yan Hydrological Station, with a catchment area of 21,000 km2 and an areal extent of alpine permafrost at ~86%) on the northeastern Qinghai-Tibet Plateau, Southwest China has been undergoing extensive changes in streamflow regimes and groundwater dynamics, permafrost degradation, and ecological deterioration under a warming climate. In general, hydrological gauges provide reliable flow records over many decades and these data are extremely valuable for assessment of changing rates and trends of streamflow. In 1998–2003, the damming of the Yellow River by the First Hydropower Station of the HAYR complicated the examination of the relations between hydroclimatic variables and streamflow dynamics. In this study, the monthly streamflow rate of the Yellow River at Huanghe’yan is reconstructed for the period of 1955–2019 using the double mass curve method, and then the streamflow at Huagnhe’yan is forecasted for the next 20 years (2020–2040) using the Elman neural network time-series method. The dam construction (1998–2000) has caused a reduction of annual streamflow by 53.5–68.4%, and a more substantial reduction of 71.8–94.4% in the drier years (2003–2005), in the HAYR. The recent removal of the First Hydropower Station of the HAYR dam (September 2018) has boosted annual streamflow by 123–210% (2018–2019). Post-correction trends of annual maximum (QMax) and minimum (QMin) streamflow rates and the ratio of the QMax/QMin of the Yellow River in the HAYR (0.18 and 0.03 m3·s−1·yr−1 and −0.04 yr−1, respectively), in comparison with those of precorrection values (−0.11 and −0.004 m3·s−1·yr−1 and 0.001 yr−1, respectively), have more truthfully revealed a relatively large hydrological impact of degrading permafrost. Based on the Elman neural network model predictions, over the next 20 years, the increasing trend of flow in the HAYR would generally accelerate at a rate of 0.42 m3·s−1·yr−1. Rising rates of spring (0.57 m3·s−1·yr−1) and autumn (0.18 m3·s−1·yr−1) discharge would see the benefits from an earlier snow-melt season and delayed arrival of winter conditions. This suggests a longer growing season, which indicates ameliorating phonology, soil nutrient availability, and hydrothermal environments for vegetation in the HAYR. These trends for hydrological and ecological changes in the HAYR may potentially improve ecological safety and water supplies security in the HAYR and downstream Yellow River basins.
Pre-Messinian Deposits of the Mediterranean Ridge: Biostratigraphic and Geochemical Evidence from the Olimpi Mud Volcano Field
Authors: Nikitas Anastasios , Triantaphyllou Maria V. , Rousakis Grigoris , Panagiotopoulos Ioannis , Pasadakis Nikolaos , Hatzianestis Ioannis , Gogou Alexandra
Published: May 2021

This study presents the results derived from micropaleontological and organic geochemical analyses of mud breccia samples obtained (through gravity coring) from five mud volcanoes (Gelendzhik, Heraklion, Moscow, Milano, Leipzig) located at the Olimpi mud volcano field on the Mediterranean Ridge accretionary complex. A thorough calcareous nannofossil semi-quantitative analysis was performed to determine the biostratigraphic assignment of the deep-seated source strata. Mudstone/shale clasts of different stratigraphic levels were identified and assigned to the Miocene nannofossil biozones CNM10, CNM8–9, CNM7, CNM6–7, and Oligocene CNO4/CNO5. A single mudstone clast from the Gelendzhik plateau, assigned to the biozone CNM10, demonstrated unique micropaleontological and geochemical characteristics, suggesting a sapropelic origin. Subsequently, the total organic carbon (TOC) content and thermal maturity of the collected mud breccias was evaluated using the Rock-Eval pyrolysis technique, and their oil and gas potential was estimated. The pyrolyzed sediments were both organic rich and organic poor (TOC >0.5% or <0.5%, respectively), with their organic matter showing characteristics of the type III kerogen that consists of adequate hydrogen to be gas generative, but insufficient hydrogen to be oil prone. However, the organic matter of the late Serravallian (CNM10) sapropelic mudstone was found to consist of a mixed type II/III kerogen, implying an oil-prone source rock.
Physicochemical Effects of Humid Air Treated with Infrared Radiation on Aqueous Solutions
Authors: Yablonskaya Olga , Voeikov Vladimir , Buravleva Ekaterina , Trofimov Aleksei , Novikov Kirill
Published: May 2021

Water vapor absorbs well in the infrared (IR) region of the spectra. On the other hand, it was recently demonstrated that IR radiation promotes formation of the so-called exclusion zones (EZ) at the interfaces between hydrophilic surfaces and water. EZ-water properties differ significantly from that of bulk water. It was studied for the first time whether treatment of water with humid air irradiated with IR-C band could change its physical-chemical properties, making it EZ-water-like. Humid air irradiated with IR was called coherent humidity (CoHu). Redox potential and surface tension decreased in deionized water and mineral water samples that were treated with CoHu, while dielectric constant increased in such water samples. After such treatment of carbonate or phosphate buffers, their buffer capacity against acidification and leaching significantly increased. No such changes were observed in water samples treated with non-irradiated humid air. Thus, after treatment of tested aqueous systems with humid air exposed to IR radiation, their properties change, making them more like EZ-water. The results suggest that IR irradiation of humid air converts it into a carrier of a certain physical signal that affects water properties.
The Relationship between River Flow Regimes and Climate Indices of ENSO and IOD on Code River, Southern Indonesia
Authors: Nugroho Adam Rus , Tamagawa Ichiro , Harada Morihiro
Published: May 2021

Predicting the streamflow regimes using climate dynamics is important in water resource management. However, in Indonesia, there are few studies targeting climate indices and streamflow. A previous study found difficulty in developing a statistical prediction model for this relationship due to its non-linear nature. This study attempted to address that gap by applying multiple regression (MR) models using second- and third-order polynomial functions to show the non-linear relationship between climate and flow regime indices. First, a correlation analysis was performed to check the variable relationships. There was a good and significant correlation of El Niño Southern Oscillation (ENSO) with the flow regime indices. Secondly, MR models were developed with the same-time variables. The developed model showed that the Indian Ocean Dipole (IOD) had the effect of strongly increasing the high flow in La Niña phases. Finally, time-lagged MRs were developed aiming at forecasting. Lagged MR models with six-month leading climate indices demonstrated a relatively good correlation with the observed data (mostly R > 0.700) with moderate accuracy (root mean square error = 44–51%). It suggests that the forecasting of flow regime may be possible using ENSO and IOD indices.
Highest Composition Dissimilarity among Phytoplankton Communities at Intermediate Environmental Distances across High-Altitude Tropical Lakes
Authors: Cartuche Alonso , Manoylov Kalina M. , Ibelings Bastiaan W. , Venail Patrick
Published: May 2021

Tropical high-altitude lakes are vital freshwater ecosystems for the functioning and dynamics of tropical high-altitude wetlands called páramos, found at over 3300 m above sea level. They play a major role in the hydrogeological cycle and provide important hydrological services such as water storage, and yet they are understudied. Describing the patterns and processes of community composition in these lakes is required to better understand the consequences of their degradation by human activities. In this study we tested the geographical and environmental components of distance–decay relationships in the phytoplankton structure across 24 tropical high-altitude lakes from Southern Ecuador. Phytoplankton composition at the phyla level showed high among-lake variation in the tropical high-altitude lakes from Tres Lagunas. We found no links, however, between the geographic distance and phytoplankton composition. On the contrary, we observed some environmentally related patterns of community structure like redox potential, altitude, water temperature, and total phosphorus. The absence of support for the distance–decay relationship observed here can result from a conjunction of local niche-based effects and dispersal limitations. Phytoplankton community composition in the Tres Lagunas system or any other ecosystem may be jointly regulated by niche-based and neutral forces that still need to be explored. Despite not proving a mechanistic explanation for the observed patterns of community structure, we hope our findings provide understanding of these vulnerable and vital ecosystems. More studies in tropical high-altitude lakes are urgently required.
Improvement Effect of Reticular Glass Fibers on the Mechanical Properties of Tailings Sand with the Lenticle (Layered Sandy Soil)
Authors: Jing Xiaofei , Pan Changshu , Chen Yulong , Li Xiangfu , Wang Wensong , Hu Xu
Published: May 2021

Glass fiber is a kind of polymer, which can effectively improve the mechanical properties of sand. However, the improvement effect of glass fibers with a reticular structure is different from that of ordinary fibers. At the same time, the sandy soil structure is diversified and part of the soil is layered, such as the lenticle in tailings dam, which often forms layered sandy soil with nearby tailings sand. The existence of the lenticle has adverse effects on the stability of the tailings dam. In order to study the reinforcement effects of reticular glass fibers on tailing sand with the lenticle (layered sand), a series of triaxial shear tests were carried out on the tailings sand by changing the layers of reticular glass fibers and the position of reinforcement. The results demonstrated the following five main points: (1) the shear strength of the tailings with the lenticle is significantly lower than the shear strength of the tailings fine sand, and the influence of the lenticle on the shear strength of the tailings is mainly concentrated on the cohesion. (2) When the reticular fiber is added to the tailings with the lenticle, the cohesion of the sample increases nonlinearly with the increase of the number of fiber layers, while the internal friction angle is basically unchanged. (3) The improvement effect of the reticular fiber on the shear strength of the sample varies with the position of the reinforcement, which is represented as the interface > tailings fine sand > lenticle. (4) Only when the axial strain develops to a certain extent, the reinforcement of the reticular fibers is reflected. (5) The reinforcement effects of reticulated fibers are determined by the interaction of forces at the interface between fibers and sand. The research results can not only provide a scientific basis for the construction of reinforced tailings dam, but also play a guiding role in disaster prevention and mitigation work of reinforced slopes with a weak zone, and even provide the reference for the reinforcement research of layered structures.
Small Catchment Runoff Sensitivity to Station Density and Spatial Interpolation: Hydrological Modeling of Heavy Rainfall Using a Dense Rain Gauge Network
Authors: Hohmann Clara , Kirchengast Gottfried , O Sungmin , Rieger Wolfgang , Foelsche Ulrich
Published: May 2021

Precipitation is the most important input to hydrological models, and its spatial variability can strongly influence modeled runoff. The highly dense station network WegenerNet (0.5 stations per km2) in southeastern Austria offers the opportunity to study the sensitivity of modeled runoff to precipitation input. We performed a large set of runoff simulations (WaSiM model) using 16 subnetworks with varying station densities and two interpolation schemes (inverse distance weighting, Thiessen polygons). Six representative heavy precipitation events were analyzed, placing a focus on small subcatchments (10–30 km2) and different event durations. We found that the modeling performance generally improved when the station density was increased up to a certain resolution: a mean nearest neighbor distance of around 6 km for long-duration events and about 2.5 km for short-duration events. However, this is not always true for small subcatchments. The sufficient station density is clearly dependent on the catchment area, event type, and station distribution. When the network is very dense (mean distance < 1.7 km), any reasonable interpolation choice is suitable. Overall, the station density is much more important than the interpolation scheme. Our findings highlight the need to study extreme precipitation characteristics in combination with runoff modeling to decompose precipitation uncertainties more comprehensively.
Predicting BOD under Various Hydrological Conditions in the Dongjin River Basin Using Physics-Based and Data-Driven Models
Authors: Lee Eunjeong , Kim Taegeun
Published: May 2021

The water quality of the Dongjin River deteriorates during the irrigation period because the supply of river maintenance water to the main river is cut off by the mass intake of agricultural weirs located in the midstream regions. A physics-based model and a data-driven model were used to predict the water quality in the Dongjin River under various hydrological conditions. The Hydrological Simulation Program–Fortran (HSPF), which is a physics-based model, was constructed to simulate the biological oxygen demand (BOD) in the Dongjin River Basin. A Gamma Test was used to derive the optimal combinations of the observed variables, including external water inflow, water intake, rainfall, and flow rate, for irrigation and non-irrigation periods. A data-driven adaptive neuro-fuzzy inference system (ANFIS) model was then built using these results. The ANFIS model built in this study was capable of predicting the BOD from the observed hydrological data in the irrigation and non-irrigation periods, without running the physics-based model. The predicted results have high confidence levels when compared with the observed data. Thus, the proposed method can be used for the reliable and rapid prediction of water quality using only monitoring data as input.
Quantifying the Contribution of Agricultural and Urban Non-Point Source Pollutant Loads in Watershed with Urban Agglomeration
Authors: Zong Min , Hu Yuanman , Liu Miao , Li Chunlin , Wang Cong , Liu Jianxin
Published: May 2021

Urban agglomeration is a new characteristic of the Chinese urbanization process, and most of the urban agglomeration is located in the same watershed. Thus, urban non-point source (NPS) pollution, especially the characteristic pollutants in urban areas, aggravates NPS pollution at the watershed scale. Many agricultural studies have been performed at the watershed scale; however, few studies have provided a study framework for estimating the urban NPS pollution in an urban catchment. In this study, an integrated approach for estimating agricultural and urban NPS pollution in an urban agglomeration watershed was proposed by coupling the Soil and Water Assessment Tool (SWAT), the event mean concentration (EMC) method and the Storm Water Management Model (SWMM). The Hun-Taizi River watershed, which contains a typical urban agglomeration and is located in northeastern China, was chosen as the study case. The results indicated that the per unit areas of total nitrogen (TN) and total phosphorus (TP) in the built-up area simulated by the EMC method were 11.9% and 23 times higher than the values simulated by the SWAT. The SWAT greatly underestimated the nutrient yield in the built-up area. This integrated method could provide guidance for water environment management plans considering agricultural and urban NPS pollution in an urban catchment.
Daily Variation of Lipid Regulators and Personal Care Products in a River Impacted by Domestic Effluents in Southern Brazil
Authors: de Almeida Brehm Goulart Franciane , Reichert Gabriela , Felippe Tais Cristina , Mizukawa Alinne , Antonelli Jhonatas , Fernandes Cristóvão Scapulatempo , de Azevedo Júlio César Rodrigues
Published: May 2021

In urban areas, wastewater treatment plants (WWTPs) play a major role in the water quality of rivers. The removal efficiency of emerging contaminants by WWTPs is strongly correlated with the type of treatment and the hydraulic retention time (HRT) of the process, which can vary according to the volumetric influent flow of wastewater and occasional peak flows. This paper aims, for the first time, to assess the daily variation of lipid regulators and personal care products in an urban river impacted by domestic effluents. Samples were collected upstream and downstream of a WWTP. The concentrations downstream of the effluent discharge were higher than upstream, but they varied significantly during the day. Concentration peaks upstream of the WWTP were detected at 07:00, 15:00 and 21:00, while downstream of the effluent discharge, concentration peaks occurred between 13:00 and 19:00 and between 21:00 and 23:00. The highest downstream concentrations of triclosan and methylparaben (420 ng L−1 and 460 ng L−1) were 6.8 and 5.4 times higher than the lowest concentrations detected, respectively. These results show that in WWTP-impacted rivers, the time of the sampling has a great influence on the final results and conclusions of a monitoring study.
Groundwater Modelling in Urban Development to Achieve Sustainability of Groundwater Resources: A Case Study of Semarang City, Indonesia
Authors: Lo Weicheng , Purnomo Sanidhya Nika , Sarah Dwi , Aghnia Sokhwatul , Hardini Probo
Published: May 2021

Since 1900, Semarang City has been meeting its industrial water needs by pumping groundwater through its underlying aquifers. The trend toward exploiting groundwater resources has driven the number of deep wells and their production capacity to increase, and therefore leads to the water table to drop from time to time, which has been marked as one of the primary causes of land subsidence there. The main aim of the current study was to numerically model the temporal and spatial evolution of groundwater table under excess abstraction so that a groundwater management strategy can be accordingly drawn up for ensuing the sustainability of groundwater resources in the future. A series of numerical simulations were carried out to take into account hydrogeological data, artificial and natural discharges of deep wells, and boundary effects in Semarang City. The groundwater modeling is calibrated under two flow conditions of the steady state from 1970 to 1990 and the transient state from 1990 to 2005 for six observation wells distributed in Semarang City. Four scenarios that reflect potential management strategies were developed, and then their effectiveness was systematically investigated. The results of our study indicate that the implementation of proper groundwater control management and measure is able to restore the groundwater level to rise back in Semarang City, and in turn achieve the sustainability of groundwater resources.
Blue Economy and Blue Activities: Opportunities, Challenges, and Recommendations for The Bahamas
Authors: Bethel Brandon J. , Buravleva Yana , Tang Decai
Published: May 2021

Following the global shutdown of tourism at the onset of the COVID-19 pandemic, small island developing states such as The Bahamas had their economies immobilized due to their heavy dependence on the industry. Beyond economic recovery in a post COVID-19 paradigm, the blue economy, blue growth, and associated activities offer pathways for a more resilient economy and is well-suited for The Bahamas. This paper suggests conduits for economic development using a traditional strength, coastal and marine tourism, in conjunction with the emerging fields of ocean renewable energy, offshore aquaculture, marine biotechnology, and bioprospecting. The interlinkages between each activity are discussed. Knowledge gaps in offshore aquaculture, ocean renewable energy, marine biotechnology, and marine environment monitoring are identified. In each sector case, strategic and tactical decision-making can be achieved through the exploitation of ocean numerical modeling and observations, and consequently should be invested in and developed alongside the requisite computational resources. Blue growth is encouraged, but instances of blue injustice are also highlighted. Crucially, pursuing blue economy activities should be given top national priority for economic recovery and prosperity.