bluuebunny/crossref_metadata_2025 huggingface dataset:
The Molecular Characterization of Hepatitis A Virus Strains Circulating during Hepatitis A Outbreaks in São Paulo, Brazil, from September 2017 to May 2019
Authors: Chuffi Samira , Gomes-Gouvêa Michele S. , Casadio Luciana V. B. , Nastri Ana Catharina S. S. , Gonzalez Mario P. , Cotia André L. F. , Aranda Amanda G. D. , Tenore Simone B. , Ono Suzane K. , Malta Fernanda M. , Madalosso Geraldine , Ferreira Paulo R. A. , Carrilho Flair J. , Pinho João R. R.
Published: January 2022

Outbreaks of hepatitis A may occur in countries of medium and high socioeconomic levels in which the population generally exhibits an increased susceptibility in young adults to this infection if they are not vaccinated against the hepatitis A virus (HAV). In Europe, an outbreak involved approximately 22 European countries with 4475 cases reported from 2016 to 2018; most of them were men who have sex with men (MSM). This outbreak expanded to North and South America, including Brazil, particularly in São Paulo city with 1547 reported cases from 2016 to 2019. In the present study, we characterized the HAV strains involved in the acute hepatitis A cases identified in the reference centers of São Paulo city during this outbreak. A total of 51 cases with positive anti-HAV IgM were included, 80.4% male, 68.6% of them between 20 and 40 years old and 41.7% MSM. HAV RNA was detected in 92% (47/51) of the cases. Subgenotype IA of HAV was identified and most of the strains were closely related to that isolated in outbreaks that occurred in different European countries in 2016. These results showed the epidemiological relation between these outbreaks and reinforce the need to implement vaccination against hepatitis A for the adult population, particularly for a population with a high-risk behavior.
Global Disparities in Hepatitis B Elimination—A Focus on Africa
Authors: Sonderup Mark W. , Spearman C. Wendy
Published: January 2022

In 2016, WHO member states at the World Health Assembly adopted a Global Health Sector Strategy that included a policy of eliminating viral hepatitis. Clear targets were established to assist in achieving this by 2030. The strategy, while achievable, has exposed existing global disparities in healthcare systems and their ability to implement such policies. Compounding this, the regions with most disparity are also those where the hepatitis B prevalence and disease burden are the greatest. Foundational to hepatitis B elimination is the identification of both those with chronic infection and crucially pregnant women, and primary prevention through vaccination. Vaccination, including the birth dose and full three-dose coverage, is key, but complete mother-to-child transmission prevention includes reducing the maternal hepatitis B viral load in the third trimester where appropriate. Innovations and simplified tools exist in order to achieve elimination, but what is desperately required is the will to implement these strategies through the support of appropriate investment and funding. Without this, disparities will continue.
A Functional Minigenome of Parvovirus B19
Authors: Reggiani Alessandro , Avati Andrea , Valenti Francesca , Fasano Erika , Bua Gloria , Manaresi Elisabetta , Gallinella Giorgio
Published: January 2022

Parvovirus B19 (B19V) is a human pathogenic virus of clinical relevance, characterized by a selective tropism for erythroid progenitor cells in bone marrow. Relevant information on viral characteristics and lifecycle can be obtained from experiments involving engineered genetic systems in appropriate in vitro cellular models. Previously, a B19V genome of defined consensus sequence was designed, synthesized and cloned in a complete and functional form, able to replicate and produce infectious viral particles in a producer/amplifier cell system. Based on such a system, we have now designed and produced a derived B19V minigenome, reduced to a replicon unit. The genome terminal regions were maintained in a form able to sustain viral replication, while the internal region was clipped to include only the left-side genetic set, containing the coding sequence for the functional NS1 protein. Following transfection in UT7/EpoS1 cells, this minigenome still proved competent for replication, transcription and production of NS1 protein. Further, the B19V minigenome was able to complement B19-derived, NS1-defective genomes, restoring their ability to express viral capsid proteins. The B19V genome was thus engineered to yield a two-component system, with complementing functions, providing a valuable tool for studying viral expression and genetics, suitable to further engineering for purposes of translational research.
A Recombinant System and Reporter Viruses for Papiine Alphaherpesvirus 2
Authors: Rahman Siregar Abdul , Gärtner Sabine , Götting Jasper , Stegen Philipp , Kaul Artur , Schulz Thomas F. , Pöhlmann Stefan , Winkler Michael
Published: January 2022

Primate simplex viruses, including Herpes simplex viruses 1 and 2, form a group of closely related herpesviruses, which establish latent infections in neurons of their respective host species. While neuropathogenic infections in their natural hosts are rare, zoonotic transmission of Macacine alphaherpesvirus 1 (McHV1) from macaques to humans is associated with severe disease. Human infections with baboon-derived Papiine alphaherpesvirus 2 (PaHV2) have not been reported, although PaHV2 and McHV1 share several biological properties, including neuropathogenicity in mice. The reasons for potential differences in PaHV2 and McHV1 pathogenicity are presently not understood, and answering these questions will require mutagenic analysis. Here, we report the development of a recombinant system, which allows rescue of recombinant PaHV2. In addition, we used recombineering to generate viruses carrying reporter genes (Gaussia luciferase or enhanced green fluorescent protein), which replicate with similar efficiency as wild-type PaHV2. We demonstrate that these viruses can be used to analyze susceptibility of cells to infection and inhibition of infection by neutralizing antibodies and antiviral compounds. In summary, we created a recombinant system for PaHV2, which in the future will be invaluable for molecular analyses of neuropathogenicity of PaHV2.
Serological Positivity against Selected Flaviviruses and Alphaviruses in Free-Ranging Bats and Birds from Costa Rica Evidence Exposure to Arboviruses Seldom Reported Locally in Humans
Authors: Barrantes Murillo Daniel Felipe , Piche-Ovares Marta , Gamboa-Solano José Carlos , Romero Luis Mario , Soto-Garita Claudio , Alfaro-Alarcón Alejandro , Corrales-Aguilar Eugenia
Published: January 2022

Arboviruses have two ecological transmission cycles: sylvatic and urban. For some, the sylvatic cycle has not been thoroughly described in America. To study the role of wildlife in a putative sylvatic cycle, we sampled free-ranging bats and birds in two arbovirus endemic locations and analyzed them using molecular, serological, and histological methods. No current infection was detected, and no significant arbovirus-associated histological changes were observed. Neutralizing antibodies were detected against selected arboviruses. In bats, positivity in 34.95% for DENV-1, 16.26% for DENV-2, 5.69% for DENV-3, 4.87% for DENV-4, 2.43% for WNV, 4.87% for SLEV, 0.81% for YFV, 7.31% for EEEV, and 0.81% for VEEV was found. Antibodies against ZIKV were not detected. In birds, PRNT results were positive against WNV in 0.80%, SLEV in 5.64%, EEEV in 8.4%, and VEEV in 5.63%. An additional retrospective PRNT analysis was performed using bat samples from three additional DENV endemic sites resulting in a 3.27% prevalence for WNV and 1.63% for SLEV. Interestingly, one sample resulted unequivocally WNV positive confirmed by serum titration. These results suggest that free-ranging bats and birds are exposed to not currently reported hyperendemic-human infecting Flavivirus and Alphavirus; however, their role as reservoirs or hosts is still undetermined.
Are There Still Difficult-to-Treat Patients with Chronic Hepatitis C in the Era of Direct-Acting Antivirals?
Authors: Pabjan Paweł , Brzdęk Michał , Chrapek Magdalena , Dziedzic Kacper , Dobrowolska Krystyna , Paluch Katarzyna , Garbat Anna , Błoniarczyk Piotr , Reczko Katarzyna , Stępień Piotr , Zarębska-Michaluk Dorota
Published: January 2022

Difficult-to-treat populations with chronic hepatitis C (CHC), in the era of interferon treatment, included patients with liver cirrhosis, kidney impairment, treatment-experienced individuals, and those coinfected with the human immunodeficiency virus. The current study aimed to determine whether, in the era of direct-acting antivirals (DAA), there are still patients that are difficult-to-treat. The study included all consecutive patients chronically infected with hepatitis C virus (HCV) who started interferon-free therapy between July 2015 and December 2020 in the Department of Infectious Diseases in Kielce. The analyzed real-world population consisted of 963 patients, and most of them were infected with genotype 1 (87.6%) with the predominance of subtype 1b and were treatment-naïve (78.8%). Liver cirrhosis was determined in 207 individuals (21.5%), of whom 82.6% were compensated. The overall sustained virologic response, after exclusion of non-virologic failures, was achieved in 98.4%. The univariable analysis demonstrated the significantly lower response rates in males, patients with liver cirrhosis, decompensation of hepatic function at baseline, documented esophageal varices, concomitant diabetes, body mass index ≥25, and previous ineffective antiviral treatment. Despite an overall very high effectiveness, some unfavorable factors, including male gender, genotype 3 infection, liver cirrhosis, and treatment experience, significantly reduce the chances for a virologic response were identified.
Co-Circulation of Chikungunya and Multiple DENV Serotypes and Genotypes, Western Indonesia 2015–2016
Authors: Harapan Harapan , Michie Alice , Ernst Timo , Panta Kritu , Mudatsir Mudatsir , Yohan Benediktus , Haryanto Sotianingsih , McCarthy Suzi , Sasmono R. Tedjo , Imrie Allison
Published: January 2022

Dengue is a mosquito-borne disease of public health concern affecting tropical and subtropical countries, including Indonesia. Although studies on dengue epidemiology have been undertaken in Indonesia, data are lacking in many areas of the country. The aim of this study was to determine dengue virus (DENV) and chikungunya virus (CHIKV) molecular epidemiology in western regions of the Indonesian archipelago. A one-year prospective study was conducted in Aceh and Jambi in 2015 and 2016, respectively, where patients with dengue-like illness were enrolled. Of 205 patients recruited, 29 and 27 were confirmed with dengue in Aceh and Jambi, respectively, and three from Jambi were confirmed with chikungunya. DENV-1 was the predominant serotype identified in Aceh while DENV-2 was predominant in Jambi. All DENV-1 and DENV-2 from both regions were classified as Genotype I and Cosmopolitan genotype, respectively, and all DENV-3 viruses from Jambi were Genotype I. Some viruses, in particular DENV-1, displayed a distinct lineage distribution, where two DENV-1 lineages from Aceh were more closely related to viruses from China instead of Jambi highlighting the role of travel and flight patterns on DENV transmission in the region. DENV-2 from both Aceh and Jambi and DENV-3 from Jambi were all closely related to Indonesian local strains. All three CHIKV belonged to Asian genotype and clustered closely with Indonesian CHIKV strains including those previously circulating in Jambi in 2015, confirming continuous and sustainable transmission of CHIKV in the region. The study results emphasize the importance of continuous epidemiological surveillance of arboviruses in Indonesia and simultaneous testing for CHIKV among dengue-suspected patients.
Metabolic Reprogramming of Glioblastoma Cells during HCMV Infection Induces Secretome-Mediated Paracrine Effects in the Microenvironment
Authors: Harrison Mark A. A. , Hochreiner Emily M. , Benjamin Brooke P. , Lawler Sean E. , Zwezdaryk Kevin J.
Published: January 2022

Glioblastoma (GBM) is an aggressive primary central nervous system neoplasia with limited therapeutic options and poor prognosis. Following reports of cytomegalovirus (HCMV) in GBM tumors, the anti-viral drug Valganciclovir was administered and found to significantly increase the longevity of GBM patients. While these findings suggest a role for HCMV in GBM, the relationship between them is not clear and remains controversial. Treatment with anti-viral drugs may prove clinically useful; however, their results do not explain the underlying mechanism between HCMV infection and GBM progression. We hypothesized that HCMV infection would metabolically reprogram GBM cells and that these changes would allow for increased tumor progression. We infected LN-18 GBM cells and employed a Seahorse Bioanalyzer to characterize cellular metabolism. Increased mitochondrial respiration and glycolytic rates were observed following infection. These changes were accompanied by elevated production of reactive oxygen species and lactate. Due to lactate’s numerous tumor-promoting effects, we examined the impact of paracrine signaling of HCMV-infected GBM cells on uninfected stromal cells. Our results indicated that, independent of viral transmission, the secretome of HCMV-infected GBM cells was able to alter the expression of key metabolic proteins and epigenetic markers. This suggests a mechanism of action where reprogramming of GBM cells alters the surrounding tumor microenvironment to be permissive to tumor progression in a manner akin to the Reverse-Warburg Effect. Overall, this suggests a potential oncomodulatory role for HCMV in the context of GBM.
Antidepressant Sertraline Is a Broad-Spectrum Inhibitor of Enteroviruses Targeting Viral Entry through Neutralization of Endolysosomal Acidification
Authors: Tseng Kuan-Chi , Hsu Bang-Yan , Ling Pin , Lu Wen-Wen , Lin Cheng-Wen , Kung Szu-Hao
Published: January 2022

Enterovirus 71 (EV71) is an etiological agent of hand foot and mouth disease and can also cause neurological complications in young children. However, there are no approved drugs as of yet to treat EV71 infections. In this study, we conducted antiviral drug screening by using a Food and Drug Administration (FDA)-approved drug library. We identified five drugs that showed dose-dependent inhibition of viral replication. Sertraline was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index among the five hits. The antiviral activity of sertraline was noted for other EV serotypes. The drug’s antiviral effect is not likely associated with its approved indications as an antidepressant and its mode-of-action as a selective serotonin reuptake inhibitor. The time-of-addition assay revealed that sertraline inhibited an EV71 infection at the entry stage. We also showed that sertraline partitioned into acidic compartments, such as endolysosomes, to neutralize the low pH levels. In agreement with the findings, the antiviral effect of sertraline could be greatly relieved by exposing virus-infected cells to extracellular low-pH culture media. Ultimately, we have identified a use for an FDA-approved antidepressant in broad-spectrum EV inhibition by blocking viral entry through the alkalization of the endolysosomal route.
Photodynamic Inactivation of Human Coronaviruses
Authors: Duguay Brett A. , Herod Adrian , Pringle Eric S. , Monro Susan M. A. , Hetu Marc , Cameron Colin G. , McFarland Sherri A. , McCormick Craig
Published: January 2022

Photodynamic inactivation (PDI) employs a photosensitizer, light, and oxygen to create a local burst of reactive oxygen species (ROS) that can inactivate microorganisms. The botanical extract PhytoQuinTM is a powerful photosensitizer with antimicrobial properties. We previously demonstrated that photoactivated PhytoQuin also has antiviral properties against herpes simplex viruses and adenoviruses in a dose-dependent manner across a broad range of sub-cytotoxic concentrations. Here, we report that human coronaviruses (HCoVs) are also susceptible to photodynamic inactivation. Photoactivated-PhytoQuin inhibited the replication of the alphacoronavirus HCoV-229E and the betacoronavirus HCoV-OC43 in cultured cells across a range of sub-cytotoxic doses. This antiviral effect was light-dependent, as we observed minimal antiviral effect of PhytoQuin in the absence of photoactivation. Using RNase protection assays, we observed that PDI disrupted HCoV particle integrity allowing for the digestion of viral RNA by exogenous ribonucleases. Using lentiviruses pseudotyped with the SARS-CoV-2 Spike (S) protein, we once again observed a strong, light-dependent antiviral effect of PhytoQuin, which prevented S-mediated entry into human cells. We also observed that PhytoQuin PDI altered S protein electrophoretic mobility. The PhytoQuin constituent emodin displayed equivalent light-dependent antiviral activity to PhytoQuin in matched-dose experiments, indicating that it plays a central role in PhytoQuin PDI against CoVs. Together, these findings demonstrate that HCoV lipid envelopes and proteins are damaged by PhytoQuin PDI and expands the list of susceptible viruses.
SARS-like Coronaviruses in Horseshoe Bats (Rhinolophus spp.) in Russia, 2020
Authors: Alkhovsky Sergey , Lenshin Sergey , Romashin Alexey , Vishnevskaya Tatyana , Vyshemirsky Oleg , Bulycheva Yulia , Lvov Dmitry , Gitelman Asya
Published: January 2022

We found and genetically described two novel SARS-like coronaviruses in feces and oral swabs of the greater (R. ferrumequinum) and the lesser (R. hipposideros) horseshoe bats in southern regions of Russia. The viruses, named Khosta-1 and Khosta-2, together with related viruses from Bulgaria and Kenya, form a separate phylogenetic lineage. We found evidence of recombination events in the evolutionary history of Khosta-1, which involved the acquisition of the structural proteins S, E, and M, as well as the nonstructural genes ORF3, ORF6, ORF7a, and ORF7b, from a virus that is related to the Kenyan isolate BtKY72. The examination of bats by RT-PCR revealed that 62.5% of the greater horseshoe bats in one of the caves were positive for Khosta-1 virus, while its overall prevalence was 14%. The prevalence of Khosta-2 was 1.75%. Our results show that SARS-like coronaviruses circulate in horseshoe bats in the region, and we provide new data on their genetic diversity.
New Evidence of Significant Association between EBV Presence and Lymphoproliferative Disorders Susceptibility in Patients with Rheumatoid Arthritis: A Systematic Review with Meta-Analysis
Authors: Banko Ana , Miljanovic Danijela , Lazarevic Ivana , Jeremic Ivica , Despotovic Aleksa , Grk Milka , Cirkovic Andja
Published: January 2022

Development of lymphoproliferative disorders (LPDs) is one of the well-known life-threatening complications in rheumatoid arthritis (RA) patients. However, there is a lack of definitive conclusions regarding the role of Epstein-Barr virus (EBV) activity in RA initiation and progression, especially in promoting LPDs. A systematic review and meta-analysis of studies that reported an EBV positive result in RA-LPD patients and controls were conducted. Studies published before 27 July 2021 were identified through PubMed, Web of Science, and SCOPUS. A total of 79 articles were included in the systematic review. The prevalence of EBV positive result among RA-LPD patients was 54% (OR = 1.54, 95% CI = 1.45–1.64). There was a statistically significant association between EBV presence and LPD susceptibility in RA patients in comparison with all controls (OR = 1.88, 95% CI = 1.29–2.73) and in comparison with LPD patients only (OR = 1.92, 95% CI = 1.15–3.19). This association was not shown in comparison with patients with autoimmune diseases other than RA who developed LPD (OR = 0.79, 95% CI = 0.30–2.09). This meta-analysis confirmed a high prevalence of EBV in the RA-LPD population. Furthermore, it provides evidence for the association between EBV presence and LPD susceptibility in RA patients, but not in those with other autoimmune diseases who developed LPD.
A Comparative Analysis of the Camera-like Eyes of Jumping Spiders and Humans
Authors: Shepeleva Irina P.
Published: January 2022

Among invertebrates, jumping spiders are one of the few groups whose representatives have camera-like eyes, and the only group whose representatives have fovea. The latter is present in the camera-like eyes of representatives of some groups of vertebrates, including humans. Based on the literature data, a comparative analysis of the camera-like eyes of jumping spiders and humans was carried out, in the course of which the similarities and differences in the properties and functions of their basic components were identified. The presented data are necessary for the formation of knowledge about jumping spiders as model animals for studying the functioning of the visual system.
Will Islamic Water Management Principles Be Included If the Helmand River Treaty Is Revisited?
Authors: Loodin Najibullah , Wolf Aaron T.
Published: January 2022

Despite the importance of water management in Islamic culture, the role of religion has been underemphasized by scholars. Using the three criteria of equity, responsibility and sustainability, this study aims to assess whether Islamic water management principles are incorporated into the revision of the transboundary Helmand River Basin under the administration of the Taliban regime. In August 2021, Taliban returned to power in Afghanistan, with a goal of ruling Afghanistan based on Islamic Sharia law, presumably including the management of the transboundary watercourses. One such basin is the Helmand, shared with the downstream Islamic Republic of Iran, with whom Afghanistan will likely revisit the transboundary Helmand River Treaty, possibly based on Islamic water management principles. We examine how principles of Islamic code may influence future negotiations, including the construction of dams on the upper Helmand River Basin initiated under the former administration.
Patterns of Past and Future Droughts in Permanent Lowland Rivers
Authors: Nazarenko Serhii , Kriaučiūnienė Jūratė , Šarauskienė Diana , Jakimavičius Darius
Published: January 2022

The problem of droughts is acute due to climate change. The study aims to assess the temporal and spatial drought patterns in Lithuanian lowland rivers in the past and to project these phenomena according to climate scenarios and models. Drought analysis was based on Standardized Precipitation Index (SPI), Reconnaissance Drought Index (RDI) and Streamflow Drought Index (SDI). To evaluate the past patterns, the hydrometeorological data of 17 rivers were used from 1961–2020. Future drought changes were analyzed in 2021–2100 according to the selected RCPs (Representative Concentration Pathways) using the hydrological model HBV. There were different patterns of droughts in three hydrological regions of Lithuania (Western, Central and Southeastern). The Southeastern region was more prone to extreme summer hydrological droughts, and they had a shorter accumulation period compared to the other two regions. SPI and RDI indices showed that the number of dry months and the minimum value of the index increased, extending the accumulation period. The highest correlation was recorded between RDI-12/SPI-12 and SDI-12. The amplitude between extremely wet and dry values of river runoff will increase according to RCP8.5. The projections indicated that hydrological drought intensity in the Central region is expected to increase under both analyzed RCPs.
A Pore Network Approach to Study Throat Size Effect on the Permeability of Reconstructed Porous Media
Authors: Xu Kai , Wei Wei , Chen Yin , Tian Haitao , Xu Sai , Cai Jianchao
Published: January 2022

Permeability is usually considered to be related to porosity. However, rocks with the same porosity may have different permeabilities in some cases, because of the variations in pore and throat size and pore space connectivity. It is vitally important to understand the effect of throat size on the transport property. In this work, five sets of regular pore network models and six core-based models are employed to study the effect of throat size on permeability. Four kinds of random distributions, i.e., uniform, normal, Weibull, and log normal, are utilized to generate random pore size. Pore coordination number is set to be two and six for the verification of the effect of connectivity on permeability. Then, single-phase flow simulation is conducted based on the constructed pore network models. The simulation results show that permeability decreases significantly when only one of the nine throats reduces to half size in terms of diameter. The influence of pore coordination number on permeability is not obvious compared to that of small throat size. This study indicates that small throats play an extremely important role in determining permeability.
SWMM-Based Assessment of Urban Mountain Stormwater Management Effects under Different LID Scenarios
Authors: Yuan Yangyang , Gan Yu , Xu Yuhan , Xie Qining , Shen Yuqing , Yin Yue
Published: January 2022

The types of urban mountains are diverse, and the surrounding environment is complex. The conditions of runoff generation and convergence in different regions of the same mountain vary. Using the Lijia Mountain in China’s Nanjing City as a case study, this study investigates the effects of such mountain-region-based LID (Low Impact Development) systems. Based on the hydrological analysis of this mountain region, SWMM (Storm Water Management Model) software is used to model and compare the runoff control effects of two LID systems schemes, namely segmental detention and retention and terminal detention and retention. The study’s findings demonstrate that the terminal detention and retention scheme can effectively delay the time of peak flooding and partly reduce peak discharge. In contrast, the segmental detention and retention scheme has a limited delay effect on flood peaks but significantly reduces the peak discharge. This research breaks through the limitations of the previous construction of a single LID scheme for mountainous regions in built-up urban areas. It serves as a theoretical model and technical reference for selecting LID scenarios in response to different mountain conditions.
Effect of Mulching and Permanent Planting Basin Dimensions on Maize (Zea mays L.) Production in a Sub-Humid Climate
Authors: Zizinga Alex , Mwanjalolo Jackson-Gilbert Majaliwa , Tietjen Britta , Bedadi Bobe , Gabiri Geofrey , Luswata Kizza Charles
Published: January 2022

In sub-humid regions, declining maize (Zea mays L.) yield is majorly attributed to unreliable rainfall and high evapotranspiration demand during critical growth stages. However, there are limited farm technologies for conserving soil water and increasing water use efficiency (WUE) in rainfed production systems amidst a changing climate. This study aimed at assessing the performance of different climate smart agriculture (CSA) practices, such as mulching and permanent planting basins (PPB), on maize growth, yield, water use efficiency and soil moisture storage. Field experiments involving mulches of 2 cm (M_2 cm), 4 cm (M_4 cm) and 6 cm (M_6 cm) thickness, permanent planting basins of 20 cm (PPB_20 cm) and 30 cm (PPB_30 cm) depths and the control/or conventional treatments were conducted for three maize growing seasons in the sub-humid climate of Western Uganda. Results indicate that maize biomass significantly increased under the tested CSA practices in the study area. Use of permanent planting basins relatively increased maize grain yield (11–66%) and water use efficiency (33–94%) compared to the conventional practice. Additionally, plots treated with mulch achieved an increase in grain yield (18–65%) and WUE (28–85%) relative to the control. Soil amendment with M_4 cm and M_6 cm significantly increased soil moisture storage compared to permanent planting basins and the conventional practice. Overall, the results highlight the positive impact of CSA practices on improving maize yield and water use efficiency in rainfed agriculture production systems which dominate the sub-humid regions.
A Hybrid Model for Streamflow Forecasting in the Basin of Euphrates
Authors: Kilinc Huseyin Cagan , Haznedar Bulent
Published: January 2022

River flow modeling plays a crucial role in water resource management and ensuring its sustainability. Therefore, in recent years, in addition to the prediction of hydrological processes through modeling, applicable and highly reliable methods have also been used to analyze the sustainability of water resources. Artificial neural networks and deep learning-based hybrid models have been used by scientists in river flow predictions. Therefore, in this study, we propose a hybrid approach, integrating long-short-term memory (LSTM) networks and a genetic algorithm (GA) for streamflow forecasting. The performance of the hybrid model and the benchmark model was taken into account using daily flow data. For this purpose, the daily river flow time series of the Beyderesi-Kılayak flow measurement station (FMS) from September 2000 to June 2019 and the data from Yazıköy from December 2000 to June 2018 were used for flow measurements on the Euphrates River in Turkey. To validate the performance of the model, the first 80% of the data were used for training, and the remaining 20% were used for the testing of the two FMSs. Statistical methods such as linear regression was used during the comparison process to assess the proposed method’s performance and to demonstrate its superior predictive ability. The estimation results of the models were evaluated with RMSE, MAE, MAPE, STD and R2 statistical metrics. The comparison of daily streamflow predictions results revealed that the LSTM-GA model provided promising accuracy results and mainly presented higher performance than the benchmark model and the linear regression model.
Biotic and Abiotic Biostimulation for the Reduction of Hexavalent Chromium in Contaminated Aquifers
Authors: Galani Andriani , Mamais Daniel , Noutsopoulos Constantinos , Anastopoulou Petra , Varouxaki Alexia
Published: January 2022

Hexavalent chromium is a carcinogenic heavy metal that needs to be removed effectively from polluted aquifers in order to protect public health and the environment. This work aims to evaluate the reduction of Cr(VI) to Cr(III) in a contaminated aquifer through the stimulation of indigenous microbial communities with the addition of reductive agents. Soil-column experiments were conducted in the absence of oxygen and at hexavalent chromium (Cr(VI)) groundwater concentrations in the 1000–2000 μg/L range. Two carbon sources (molasses and EVO) and one iron electron donor (FeSO4·7H2O) were used as ways to stimulate the metabolism and proliferation of Cr(VI) reducing bacteria in-situ. The obtained results indicate that microbial anaerobic respiration and electron transfer can be fundamental to alleviate polluted groundwater from hazardous Cr(VI). The addition of organic electron donors increased significantly Cr(VI) reduction rates in comparison to natural soil attenuation rates. Furthermore, a combination of organic carbon and iron electron donors led to a longer life span of the remediation process and thus increased total Cr(VI) removal. This is the first study to investigate biotic and abiotic Cr(VI) removal by conducting experiments with natural soil and by applying biostimulation to modify the natural existing microbial communities.
An Introduction to the Special Issue “Geochemical Processes of Karst and Karst Paleoenvironments” as Part of the International Year of Caves and Karst
Authors: Veni George
Published: January 2022

About 15 [...]
Metacommunity Concepts Provide New Insights in Explaining Zooplankton Spatial Patterns within Large Floodplain Systems
Authors: Liu Baogui , Zhou Chuanqiao , Zheng Lilin , Duan Haixin , Chen Ying , Wang Guoxiang
Published: January 2022

Flood pulse related physical variables (FLOOD) can affect zooplankton community structure through local factors directly and can also influence through regional dispersal factors of metacommunity concepts indirectly. Therefore, we infer that spatial patterns of zooplankton communities could be related to metacommunity concepts and their importance may depend on the size of the aquatic/terrestrial transition zone (ATTZ). Herein, we explored the relative importance of limnological (LIMNO) and FLOOD variables in zooplankton community by analyzing data from 272 sites across three floodplain lakes in the middle reaches of the Yangtze River. Our results showed that the variation in the zooplankton community can be well explained by the LIMNO and FLOOD variables in all of the lakes under the low water level season. However, during the high water level season, neither LIMNO nor FLOOD can explain the spatial variances of zooplankton. Therefore, our results indicated that testing biogeographical theories and macroecological laws using zooplankton should consider temporal aspects of flood pulse. Furthermore, we noted that the number of explained variance by local variables is negatively correlated with the size of the ATTZ. Metacommunity concepts provide complementary insights in explaining zooplankton spatial patterns within large floodplain systems, which also provide a theoretical basis for ATTZ protection in floodplain management.
Integrating Stable Isotopes with Mean Residence Time Estimation to Characterize Groundwater Circulation in a Metamorphic Geothermal Field in Yilan, Taiwan
Authors: Kuo Ching-Huei , Li Pi-Yi , Lin Jun-Yi , Chen Yi-Lin
Published: January 2022

This paper presents a water circulation model by combing oxygen and hydrogen stable isotopes and mean residence time (MRT) estimation in a high-temperature metamorphic geothermal field, Tuchen, in Yilan, Taiwan. A total of 18 months of oxygen and hydrogen stable isotopes of surface water and thermal water show the same variation pattern, heavier values in summer and lighter values in the rest of the year. A shift of δ18O with a relative constant δD indicates the slow fluid–rock interaction process in the study area. Two adjacent watersheds, the Tianguer River and Duowang River, exhibit different isotopic values and imply different recharge altitudes. The seasonal variation enabled us to use stable isotope to estimate mean residence time of groundwater in the study area. Two wells, 160 m and 2200 m deep, were used to estimate mean residence time of the groundwater. Deep circulation recharges from higher elevations, with lighter isotopic values, 5.9‰ and 64‰ of δ18O and δD, and a longer mean residence time, 1148 days, while the shallow circulation comes from another source with heavier values, 5.7‰ and 54.4‰ of δ18O and δD, and a shorter mean residence time, 150 days. A two-circulation model was established based on temporal and spatial distribution characteristics of stable isotopes and the assistance of MRT. This study demonstrates the usefulness of the combined usage for further understanding water circulation of other various temperatures of metamorphic geothermalfields.
Runoff Prediction Based on the Discharge of Pump Stations in an Urban Stream Using a Modified Multi-Layer Perceptron Combined with Meta-Heuristic Optimization
Authors: Lee Won Jin , Lee Eui Hoon
Published: January 2022

Runoff in urban streams is the most important factor influencing urban inundation. It also affects inundation in other areas as various urban streams and rivers are connected. Current runoff predictions obtained using a multi-layer perceptron (MLP) exhibit limited accuracy. In this study, the runoff of urban streams was predicted by applying an MLP using a harmony search (MLPHS) to overcome the shortcomings of MLPs using existing optimizers and compared with the observed runoff and the runoff predicted by an MLP using a real-coded genetic algorithm (RCGA). Furthermore, the results of the MLPHS were compared with the results of the MLP with existing optimizers such as the stochastic gradient descent, adaptive gradient, and root mean squared propagation. The runoff of urban steams was predicted based on the discharge of each pump station and rainfall information. The results obtained with the MLPHS exhibited the smallest error of 39.804 m3/s when compared to the peak value of the observed runoff. The MLPHS gave more accurate runoff prediction results than the MLP using the RCGA and that using existing optimizers. The accurate prediction of the runoff in an urban stream using an MLPHS based on the discharge of each pump station is possible.
Hybrid Fuzzy Multi-Criteria Analysis for Selecting Discrete Preferable Groundwater Recharge Sites
Authors: Papadopoulos Christopher , Spiliotis Mike , Pliakas Fotios , Gkiougkis Ioannis , Kazakis Nerantzis , Papadopoulos Basil
Published: January 2022

This study proposes a hybrid fuzzy multi-criteria methodology for the selection of the most preferable site for applying managed aquifer recharge (MAR) systems by utilizing floodwaters. The use of MAR can increase water resources for later water utilization in case of drought. In this multi-criteria problem, seven recharge sites are under consideration, based on nine criteria, aiming to make a final list of their relative ranking. A fuzzy analytic hierarchy process (FAHP) based on the logarithmic fuzzy preference programming (LFFP) method is used to determine the weights of criteria. LFFP is an optimization-based method that produces a priority vector from a fuzzy pairwise comparison matrix. Furthermore, fuzzy inference systems (FIS) based on the Mamdani approach are used to estimate the rating of each alternative with respect to the criterion examined, and then the final evaluation of the alternatives is obtained. A FIS is a fuzzy if–then rule-based system where the experts’ qualitative knowledge is translated into numerical reasoning for each individual criterion. The proposed methodology is applied in the aquifer system of the agricultural plain located to the southeast of the city of Xanthi in the Prefecture of Xanthi, NE Greece.
Climate Change Attribution in the Lena and Selenga River Runoff: An Evaluation Based on the Earth System and Regional Hydrological Models
Authors: Kalugin Andrey
Published: January 2022

The main goal of this study was to obtain the attribution results of a physical assessment of the modern hydrological consequences of separately natural and anthropogenic components of climate change, based on the synthesis of detailed process-based models of river runoff formation and an ensemble of Earth system models (ESMs) within the large river basins in Eastern Siberia. This approach allows calculating the river flow using ESM-based data over the observation period under two scenarios, considering: (1) the anthropogenic impact of increasing greenhouse gas emissions and (2) only internal fluctuations of the climate system and natural external forcing. According to the results of the numerical experiments, the attributions of anthropogenic components of climate change in the dynamics of the Lena runoff are weak, i.e., during the observation period, the Lena River flow statistically significantly increases, but it occurs mainly due to natural climate variability. The changes in the Selenga runoff are intensely influenced by the anthropogenic component of climate change. Since the 1970s, the Selenga runoff increased under natural climatic conditions, but since the mid-1980s, it decreased under anthropogenic greenhouse gas emissions, due to reduced summer precipitation. This was the main reason for the last low-water period of 1996–2017 in the Selenga basin.
Aspergillus niger Culture Filtrate (ACF) Mediated Biocontrol of Enteric Pathogens in Wastewater
Authors: Subhash Suja , Babu Pradeesh , Vijayakumar Amrutha , Suresh Reshma Alookaran , Madhavan Ajith , Nair Bipin Gopalakrishnan , Pal Sanjay
Published: January 2022

Robust control of pathogens in sewage facilitates safe reuse of wastewater rich in valuable nutrients for potential valorization through biological means. Aspergillus niger is widely reported in bioremediation of wastewater but studies on control of enteric pathogens in sewage are very sparse. So, this study aimed at exploring the antibacterial and nematicidal activity of A. niger culture filtrate (ACF). Antibacterial activity of ACF on enteric pathogens (Klebsiella pneumoniae, Pseudomonas aeruginosa, Vibrio cholerae, Salmonella enterica, Shigella dysenteriae, Escherichia coli, Staphylococcus aureus, Klebsiella variicola) was determined by spectrophotometric growth analysis, resazurin based viability assay and biofilm formation assay. ACF showed inhibition against all enteric pathogens except Pseudomonas aeruginosa. Nematicidal studies on Caenorhabditis elegans showed 85% egg hatch inhibition and 52% mortality of L1 larvae. Sewage treatment with ACF at 1:1 (v/v) showed 2–3 log reduction in coliforms, Klebsiella, Shigella, Salmonella, S. aureus and Vibrio except Pseudomonas, indicating significant alteration of complex microbial dynamics in wastewater. Application of ACF can potentially be used as a robust biocontrol strategy against infectious microbes in wastewater and subsequent valorization by cultivating beneficial Pseudomonas.
Heavy Metals and Nutrients Loads in Water, Soil, and Crops Irrigated with Effluent from WWTPs in Blantyre City, Malawi
Authors: Malikula Raymond S. , Kaonga Chikumbusko C. , Mapoma Harold W. T. , Thulu Fabiano G. D. , Chiipa Petra
Published: January 2022

Heavy metals may cause acute and chronic toxic effects to humans and other organisms, hence the need to treat wastewater properly, as it contains these toxicants. This work aimed at assessing zinc, copper, cadmium, and chromium in water, soil, and plants that are irrigated with effluent from Manase and Soche Wastewater Treatment Plants (WWTPs) in Blantyre, Malawi. Atomic Absorption Spectrophotometry (AAS) was used to assess the heavy metals. Heavy Metal Health Risk Assessment (HMHRA) on plants (vegetables) around both WWTPs was also conducted. Average daily dose (ADD) and target hazard quotients (THQ) were used to assess HMHRA. Physicochemical parameters were determined using standard methods from American Public Health Association (APHA). The heavy metal ranges were below detection limit (BDL) to 6.94 mg/L in water, 0.0003 to 4.48 mg/kg in soil, and 3 to 32 mg/L in plants. The results revealed that plants irrigated with effluent from WWTP had high values of aforementioned metals exceeding the Malawi Standards and WHO permissible limits. Furthermore, the health risk assessment values showed that vegetables consumed for a long period of time from Manase WWTP were likely to cause adverse health effects as compared to those from Soche WWTP.
Geochemical Markers as a Tool for the Characterization of a Multi-Layer Urban Aquifer: The Case Study of Como (Northern Italy)
Authors: Binda Gilberto , Frascoli Francesca , Spanu Davide , Ferrario Maria F. , Terrana Silvia , Gambillara Roberto , Trotta Sara , Noble Paula J. , Livio Franz A. , Pozzi Andrea , Michetti Alessandro M.
Published: January 2022

The analysis of geochemical markers is a known valid tool to explore the water sources and understand the main factors affecting natural water quality, which are known issues of interest in environmental science. This study reports the application of geochemical markers to characterize and understand the recharge areas of the multi-layer urban aquifer of Como city (northern Italy). This area presents a perfect case study to test geochemical markers: The hydrogeological setting is affected by a layered karst and fractured aquifer in bedrock, a phreatic aquifer hosted in Holocene sediments and connected with a large freshwater body (Lake Como); the aquifers recharge areas and the water geochemistry are unknown; the possible effect of the tectonic setting on water flow was overlooked. In total, 37 water samples were collected including water from two stacked aquifers and surface water to characterize hydrochemical features. Moreover, six sediment samples in the recent palustrine deposits of the Como subsurface were collected from cores and analyzed to understand the main geochemistry and mineralogy of the hosting material. The chemical analyses of water allow to observe a remarkable difference between the shallow and deep aquifers of the study area, highlighting different recharge areas, as well as a different permanence time in the aquifers. The sediment geochemistry, moreover, confirms the differences in trace elements derived from sediment-water interaction in the aquifers. Finally, an anomalous concentration of As in the Como deep aquifer was observed, suggesting the need of more detailed analyses to understand the origin of this element in water. This study confirms the potentials of geochemical markers to characterize main factors affecting natural water quality, as well as a tool for the reconstruction of recharge areas.
Water Turbidity Retrieval Based on UAV Hyperspectral Remote Sensing
Authors: Cui Mengying , Sun Yonghua , Huang Chen , Li Mengjun
Published: January 2022

The water components affecting turbidity are complex and changeable, and the spectral response mechanism of each water quality parameter is different. Therefore, this study mainly aimed at the turbidity monitoring by unmanned aerial vehicle (UAV) hyperspectral technology, and establishes a set of turbidity retrieval models through the artificial control experiment, and verifies the model’s accuracy through UAV flight and water sample data in the same period. The results of this experiment can also be extended to different inland waters for turbidity retrieval. Retrieval of turbidity values of small inland water bodies can provide support for the study of the degree of water pollution. We collected the images and data of aquaculture ponds and irrigation ditches in Dawa District, Panjin City, Liaoning Province. Twenty-nine standard turbidity solutions with different concentration gradients (concentration from 0 to 360 NTU—the abbreviation of Nephelometric Turbidity Unit, which stands for scattered turbidity.) were established through manual control and we simultaneously collected hyperspectral data from the spectral values of standard solutions. The sensitive band to turbidity was obtained after analyzing the spectral information. We established four kinds of retrieval, including the single band, band ratio, normalized ratio, and the partial least squares (PLS) models. We selected the two models with the highest R2 for accuracy verification. The band ratio model and PLS model had the highest accuracy, and R2 was, respectively, 0.65 and 0.72. The hyperspectral image data obtained by UAV were combined with the PLS model, which had the highest R2 to estimate the spatial distribution of water turbidity. The turbidity of the water areas in the study area was 5–300 NTU, and most of which are 5–80 NTU. It shows that the PLS models can retrieve the turbidity with high accuracy of aquaculture ponds, irrigation canals, and reservoirs in Dawa District of Panjin City, Liaoning Province. The experimental results are consistent with the conclusions of the field investigation.