bluuebunny/crossref_metadata_2025 huggingface dataset:
Stable Isotopic Evidence for Nutrient Rejuvenation and Long-Term Resilience on Tikopia Island (Southeast Solomon Islands)
Authors: Swift Jillian A. , Kirch Patrick V. , Ilgner Jana , Brown Samantha , Lucas Mary , Marzo Sara , Roberts Patrick
Published: August 2021

Tikopia Island, a small and relatively isolated Polynesian Outlier in the Southeast Solomon Islands, supports a remarkably dense human population with minimal external support. Examining long-term trends in human land use on Tikopia through archaeological datasets spanning nearly 3000 years presents an opportunity to investigate pathways to long-term sustainability in a tropical island setting. Here, we trace nutrient dynamics across Tikopia’s three pre-European contact phases (Kiki, Sinapupu, Tuakamali) via stable carbon and nitrogen isotope analysis of commensal Pacific rat (Rattus exulans) and domestic pig (Sus scrofa) bone and tooth dentine collagen. Our results show a decline in δ15N values from the Kiki (c. 800 BC-AD 100) to Sinapupu (c. AD 100–1200) phases, consistent with long-term commensal isotope trends observed on other Polynesian islands. However, increased δ15N coupled with lower δ13C values in the Tuakamali Phase (c. AD 1200–1800) point to a later nutrient rejuvenation, likely tied to dramatic transformations in agriculture and land use at the Sinapupu-Tuakamali transition. This study offers new, quantifiable evidence for deep-time land and resource management decisions on Tikopia and subsequent impacts on island nutrient status and long-term sustainability.
Remote Detection of Cyanobacterial Blooms and Chlorophyll-a Analysis in a Eutrophic Reservoir Using Sentinel-2
Authors: Viso-Vázquez Manuel , Acuña-Alonso Carolina , Rodríguez Juan Luis , Álvarez Xana
Published: August 2021

Harmful cyanobacterial blooms have been one of the most challenging ecological problems faced by freshwater bodies for more than a century. The use of satellite images as a tool to analyze these blooms is an innovative technology that will facilitate water governance and help develop measures to guarantee water security. To assess the viability of Sentinel-2 for identifying cyanobacterial blooms and chlorophyl-a, different bands of the Sentinel-2 satellite were considered, and those most consistent with cyanobacteria analysis were analyzed. This analysis was supplemented by an assessment of different indices and their respective correlations with the field data. The indices assessed were the following: Normalized Difference Water Index (NDWI), Normalized Differences Vegetation Index (NDVI), green Normalized Difference Vegetation Index (gNDVI), Normalized Soil Moisture Index (NSMI), and Toming’s Index. The green band (B3) obtained the best correlating results for both chlorophyll (R2 = 0.678) and cyanobacteria (R2 = 0.931). The study by bands of cyanobacteria composition can be a powerful tool for assessing the physiology of strains. NDWI gave an R2 value of 0.849 for the downstream point with the concentration of cyanobacteria. Toming’s Index obtained a high R2 of 0.859 with chlorophyll-a and 0.721 for the concentration of cyanobacteria. Notable differences in correlation for the upstream and downstream points were obtained with the indices. These results show that Sentinel-2 will be a valuable tool for lake monitoring and research, especially considering that the data will be routinely available for many years and the images will be frequent and free.
Applying UTAUT in Predicting ESL Lecturers Intention to Use Flipped Learning
Authors: Abd Rahman Siti Fatimah , Md Yunus Melor , Hashim Harwati
Published: August 2021

Flipped learning empowers learners to take an engaging role in learning while educators assist the learning process. The employment of flipped learning has been confirmed to enhance the teaching and learning of English as a second language in previous studies. This study aimed to explore the application of the unified theory of technology acceptance and use of technology towards ESL lecturers’ intention to use flipped learning. This study used a quantitative research framework where a set of online questionnaires was used in collecting the data. A total of 206 English as a second language lecturers from four different universities participated in this study. The data were analyzed using structural equation modeling. The result of this study indicates that only social influence is significant in predicting English as a second language lecturers’ intention to use the flipped learning approach. Furthermore, this study enriches the literature on 21st century education and the integration of technology in teaching and learning. In addition, this study could help educators and stakeholders in adapting or enhancing the flipped learning approach by distinguishing the distinct predictors of technology acceptance.
How Instagram Influencers Affect the Value Perception of Thai Millennial Followers and Purchasing Intention of Luxury Fashion for Sustainable Marketing
Authors: Jansom Akawut , Pongsakornrungsilp Siwarit
Published: August 2021

Social media influencers play a significant role in marketing by introducing products to their followers. We investigate how Instagram influencers impact consumer parasocial interaction (PSI) in the relationship between value perception and purchase intention. Whereas customers influence the attractiveness (social and physical) PSI of social media influencers, studies of the effects of luxury purchasing PSI in Thailand are limited. We examine the relationship between PSI and followers of luxury fashion’s value (social, personal, and conspicuous) on social media. We use structural equation modeling to evaluate hypotheses by conducting an online survey with 400 Thai millennial respondents who had experience following influencers on Instagram. The findings indicate that Thai millennials accept Instagram influencers’ PSIs in terms of value perception and motivation to purchase luxury fashion. The attractiveness of influencers initiates the formation of PSI; followers receive value perception and react to purchasing intention from influencers. The concepts were investigated to prove that influencers’ power can encourage followers to mitigate negative consequences by delivering value perceptions on PSI. These findings provided managerial implications for comprehending consumers in the field of digitalization.
Optimization of Granulation Process for Binder-Free Biochar-Based Fertilizer from Digestate and Its Slow-Release Performance
Authors: Yu Zhou , Zhao Jie , Hua Yinfeng , Li Xiaoying , Chen Qincheng , Shen Guoqing
Published: August 2021

Granulation of biochar-based fertilizer is one potential method to reduce transportation costs, provide for enhanced handling, and decrease the loss of fertilizer during soil application. This study aimed to synthesize binder-free biogas residue biochar-based fertilizer (RBF) pellets and investigate their physical properties and slow-release potential. Results showed that the physical properties and forming quality of the pellets reached the best when the moisture content was 7.84%, the diameter was 7 mm, the compression speed was 49.54 mm/min, and the molding pressure was 7.5 MPa. Sustained-release kinetic analysis and characterization results identified that the RBF had excellent nitrogen (N), phosphorus (P), and potassium (K) sustained release properties. The sustained release of nutrients gradually increased with the drying temperature, and the sustained-release effect of P was the best, followed by that of N and K. Therefore, RBF pellets may be applied as a green slow-release fertilizer in agricultural production. Physical, chemical, and slow-release properties could be improved by optimizing the drying and granulation process parameters, thus providing a new idea for the combination of kitchen waste recycling and sustainable agricultural development.
Do Knowledge and Experience Value Affect Green Tourism Activity Participation and Buying Decision? A Case Study of Natural Dyeing Experience in China
Authors: Zhang Xiaocheng Vicky , Chan Suk Ha Grace
Published: August 2021

With the rapid development of niche tourism, green tourism activity has become known to the wider public. By taking into account the extended theory of planned behaviour (TPB), this study takes natural dyeing experience as a case study, with the aim of determining the tourist purchase intention of green products under the destination experience scenario. A quantitative approach was adopted, and 349 valid sets of data were collected from individuals who have participated in natural dyeing activities. Partial least squares–structural equation modelling (PLS–SEM) analysis was conducted to test the conceptual model. The results indicate that experience value (EV) had a significant impact on green purchase conception and intention. In addition, subjective norm had a significant positive influence on tourism green purchase attitude. However, environmental knowledge failed to predict green purchase attitude and perceived behavioural control. The PLS–SEM analysis confirmed the extended TPB model, which showed relatively good predictive validity. Findings suggest that TPB mediated the relationship between EV and purchase intention. The extended model considerably contributes to improving understanding of the impact on green tourism products and dissects theoretical and practical implications to practitioners. Apart from strengthening the experience value from attaining, learning, escapism, and fantasy aspects, on the basis of previous literature, this study concludes that practically, environmental education regarding the experimental environment in tourism destinations in China should return to green activity itself and induce the support of green tourism products. Tourism marketers should trigger personal green knowledge through sense experience in the process of stimulating and promoting green tourism activities, as well as stimulate purchasing power.
Design of a Power System Supervisory Control with Linear Optimization for Electrical Load Management in an Aircraft On-Board DC Microgrid
Authors: Rubino Luigi , Rubino Guido , Conti Paolo
Published: August 2021

In modern aircraft, energy supply management has become a critical matter, since many aboard electrical loads have to be supplied, especially those related to flight safety. However, at the same time, the size and weight of electrical generators must be limited because of their on-board installation. In this paper, the Mixed Integrated Linear Programming (MILP) methodology has been used to formulate the Supervisor definition of the direct current (DC) microgrid (MG) on-board system with an extension for the programmable loads. Due to the problem of dimension increase, two methods have been presented and tested to perform optimal energy management (EM) aboard an aircraft: the Branch and Bound (B&B) and the Linear Regression Approximation (LRA). Finally, numerical simulations and results have been provided to validate the proposed optimization methodologies, according to the dimensions and the complexity of the problem.
Machine Learning with Metaheuristic Algorithms for Sustainable Water Resources Management
Authors: Kisi Ozgur
Published: August 2021

Management of available water resources needs good planning and to do this, prognostication of hydrological parameters (parameters of the hydrological cycle such as rainfall, runoff, solar radiation, groundwater, evaporation/evapotranspiration) [...]
The Effects of Different Natural Environment Influences on Health and Psychological Well-Being of People: A Case Study in Selangor
Authors: Raman Thivya Laxshmy , Abdul Aziz Nor Akmar , Yaakob Sam Shor Nahar
Published: August 2021

Background: People benefit from the recreational services provided by an urban corridor, urban park, and urban forest. Due to ongoing land-use interest and urban development, however, these natural environments are coming under increasing pressure. Simultaneously, the world is becoming increasingly urbanised, and living in cities has been linked to mental health issues. On the other hand, different natural environments are known to create healthier environments, and the need for effective restorative environments has never been greater. The purpose of the study was to compare the impacts of walking in different natural environments. Methods: I) Kota Damansara Community Forest Reserve, II) Mutiara Damansara Recreational Park, and III) the Urban Green Corridor along Jalan PJU 7/2 were used as control study sites in this study. Each site was visited only once by the study participants (40 women and 40 men). Walking for 30 min was a part of the experiment. To identify the psychological effects of different natural environments, the Depression, Anxiety, and Stress Scale (DASS21), Profile of Mood States (POMS), Positive and Negative Affect Schedule (PANAS), and Restoration Outcome Scale (ROS) were utilised. Results: In all three natural environments, the restorative effects were found to increase significantly. Conclusion: The overall conclusion of the field experiment is that being in an urban green corridor can also provide a refreshing environment. In terms of stress reduction among working adults, the recreational park is sufficient, while urban-forested areas are more effective in improving mental health by minimising stress, anxiety, and depression.
Airline Chief Executive Officer and Corporate Social Responsibility
Authors: Jing Luo , Moon Joonho
Published: August 2021

The aim of this research is to explore the determinants of airline CSR. Stakeholder theory is the theoretical underpinning. Chief executive officers (CEOs) are the research target, which is theoretically underpinned by upper echelon theory. For data collection, this study used data from COMPUSTAT, EXECUCOMP, KLD MSCI, LinkedIn, and the Bureau of Economic Analysis. Standard industry classification code 4512 was employed to obtain information on airline companies. Moreover, the number of observations was 154, the number of firms was 15, and the study period was 1999–2016. CSR domains include employment, the environment, and the product. The explanatory attributes are the CEO’s age, tenure, education, share ownership, stock option, and duality. Ordinary least squares and feasible generalized least squares regression analyses were executed for hypothesis testing. Regarding the results, employment CSR was positively affected by CEO age. This study found an inverted U-shaped relationship between CEO tenure and environmental CSR. Environmental CSR was also negatively influenced by stock options. Product CSR was positively associated with CEO age, whereas it was negatively associated with CEO duality.
Coping with COVID-19: The Resilience and Transformation of Community-Based Tourism in Brunei Darussalam
Authors: Noorashid Najib , Chin Wei Lee
Published: August 2021

The COVID-19 pandemic heavily impacted the travel and tourism industry, economies, livelihoods, public services, and opportunities globally. This is also observed in the small country of Brunei. As one of the few countries that have successfully mitigated COVID-19 transmissions, Brunei is slowly rebuilding its tourism industry through its community-based tourism (CBT). Following Sharma et al.’s resilience-based framework for reviving the tourism industry post-COVID-19 established in 2021, this study incorporates responses from semi-structured interviews with 16 local CBT owners on the challenges, the management, and the CBT initiatives during the height of the pandemic until today. These initiatives include diversifying more tour packages and utilising local resources and products. Despite the lockdown imposed by the government, which suspended businesses and restricted all travelling, local CBT operations flourished, generated more income for the owners, and created job opportunities for the community. Such efforts have caused the public to appreciate local cultures, the environment, and ultimately increase CBT experiences in the country. While shedding light on Brunei’s unique management of its tourism industry during the pandemic, this paper also demonstrates theoretical and conceptual contributions to the recent literature of resilient and transformational tourism and provide suggestions on how to manage CBT operations during these challenging times.
Deep Learning-Based Residual Control Chart for Binary Response
Authors: Kim Jong Min , Ha Il Do
Published: August 2021

A residual (r) control chart of asymmetrical and non-normal binary response variable with highly correlated explanatory variables is proposed in this research. To avoid multicollinearity between multiple explanatory variables, we employ and compare a neural network regression model and deep learning regression model using Bayesian variable selection (BVS), principal component analysis (PCA), nonlinear PCA (NLPCA) or whole multiple explanatory variables. The advantage of our r control chart is able to process both non-normal and correlated multivariate explanatory variables by employing a neural network model and deep learning model. We prove that the deep learning r control chart is relatively efficient to monitor the simulated and real binary response asymmetric data compared with r control chart of the generalized linear model (GLM) with probit and logit link functions and neural network r control chart.
Complexity Parameters for Molecular Solids
Authors: Banaru Alexander M. , Aksenov Sergey M. , Krivovichev Sergey V.
Published: August 2021

Structural complexity measures based on Shannon information entropy are widely used for inorganic crystal structures. However, the application of these parameters for molecular crystals requires essential modification since atoms in inorganic compounds usually possess more degrees of freedom. In this work, a novel scheme for the calculation of complexity parameters (HmolNet, HmolNet,tot) for molecular crystals is proposed as a sum of the complexity of each molecule, the complexity of intermolecular contacts, and the combined complexity of both. This scheme is tested for several molecular crystal structures.
An Advised Indirect-Utility Ranking of Opportunity Sets
Authors: García-Sanz María Dolores , Alcantud José Carlos R.
Published: August 2021

There is a substantial strand of literature about ranking the subsets of a set of alternatives, usually referred to as opportunity sets. We investigate a model that is dependent on the preference of a grand set of alternatives. In this framework, the indirect-utility criterion ranks the opportunity sets by the following rule: a subset A is weakly preferred to another subset B if and only if A contains at least one preference maximizing element from A∪B. This criterion leads to the indifference of each subset of alternatives to a singleton; symmetry appears at this stage, as the property holds true for any one of the maximizers in A. Conversely, suppose that a ranking of opportunity sets satisfies the property that each opportunity set is indifferent to a singleton contained within it. Then, we prove that such a ranking must use a generalized form of the indirect-utility criterion, where maximization is applied to a selection of the alternatives. Altogether, these results produce a characterization of the advised indirect-utility criterion for ranking opportunity sets.
np-Pair Correlations in the Isovector Pairing Model
Authors: Pan Feng , He Yingwen , Dai Lianrong , Qi Chong , Draayer Jerry P.
Published: August 2021

A diagonalization scheme for the shell model mean-field plus isovector pairing Hamiltonian in the O(5) tensor product basis of the quasi-spin SUΛ(2) ⊗ SUI(2) chain is proposed. The advantage of the diagonalization scheme lies in the fact that not only can the isospin-conserved, charge-independent isovector pairing interaction be analyzed, but also the isospin symmetry breaking cases. More importantly, the number operator of the np-pairs can be realized in this neutron and proton quasi-spin basis, with which the np-pair occupation number and its fluctuation at the J = 0+ ground state of the model can be evaluated. As examples of the application, binding energies and low-lying J = 0+ excited states of the even–even and odd–odd N∼Z ds-shell nuclei are fit in the model with the charge-independent approximation, from which the neutron–proton pairing contribution to the binding energy in the ds-shell nuclei is estimated. It is observed that the decrease in the double binding-energy difference for the odd–odd nuclei is mainly due to the symmetry energy and Wigner energy contribution to the binding energy that alter the pairing staggering patten. The np-pair amplitudes in the np-pair stripping or picking-up process of these N = Z nuclei are also calculated.
Noether Currents and Maxwell-Type Equations of Motion in Higher Derivative Gravity Theories
Authors: Kugo Taichiro
Published: August 2021

In general coordinate invariant gravity theories whose Lagrangians contain arbitrarily high order derivative fields, the Noether currents for the global translation and for the Nakanishi’s IOSp(8|8) choral symmetry containing the BRS symmetry as its member are constructed. We generally show that for each of these Noether currents, a suitable linear combination of equations of motion can be brought into the form of a Maxwell-type field equation possessing the Noether current as its source term.
Obituary for Prof. Dr. Steven Weinberg
Authors: Odintsov Sergei D.
Published: August 2021

With deep sadness, we announce that on 23 July 2021 our Editorial Board Member Steven Weinberg passed away [...]
Resistance Evaluation of Dominant Varieties against Southern Rice Black-Streaked Dwarf Virus in Southern China
Authors: Zhou Shunkang , Zhao Yaling , Liang Zhenyi , Wu Ruifeng , Chen Biao , Zhang Tong , Yang Xin , Zhou Guohui
Published: August 2021

Southern rice black-streaked dwarf virus (SRBSDV), a Fijivirus in the Reoviridae family, is transmitted by the white-backed planthopper (Sogatella furcifera, WBPH), a long-distance migratory insect, and presents a serious threat to rice production in Asia. It was first discovered in China’s Guangdong Province in 2001 and has been endemic in the south of China and north of Vietnam for two decades, with serious outbreaks in 2009, 2010, and 2017. In this study, we evaluated the resistance of 10 dominant rice varieties from southern China, where the virus overwinters and accumulates as a source of early spring reinfection, against this virus by artificial inoculation. The results showed that in all tested varieties there was no immune resistance, but there were differences in the infection rate, with incidence rates from 21% to 90.7%, and in symptom severity, with plant weight loss from 66.71% to 91.20% and height loss from 34.1% to 65.06%. Additionally, and valuably, the virus titer and the insect vector virus acquisition potency from diseased plants were significantly different among the varieties: an over sixfold difference was determined between resistant and susceptible varieties, and there was a positive correlation between virus accumulation and insect vector virus acquisition. The results can provide a basis for the selection of rice varieties in southern China to reduce the damage of SRBSDV in this area and to minimize the reinfection source and epidemics of the virus in other rice-growing areas.
One-Year Outcomes after Ledipasvir/Sofosbuvir Treatment of Chronic Hepatitis C in Teenagers with and without Significant Liver Fibrosis—A Case Series Report
Authors: Pokorska-Śpiewak Maria , Dobrzeniecka Anna , Marczyńska Magdalena
Published: August 2021

One-year outcomes after therapy with ledipasvir/sofosbuvir (LDV/SOF) in children with chronic hepatitis C (CHC) presenting with and without significant liver fibrosis were analyzed. We included patients aged 12–17 years treated with LDV/SOF, presenting with significant fibrosis (F ≥ 2 on the METAVIR scale) in transient elastography (TE) at the baseline and we compared the outcomes with that of patients without fibrosis. Patients were followed every 4 weeks during the treatment, at the end of the therapy, at week 12 posttreatment, and one year after the end of treatment. Liver fibrosis was established using noninvasive methods: TE, aspartate transaminase-to-platelet ratio index (APRI), and Fibrosis-4 index (FIB-4). There were four patients with significant fibrosis at baseline: one with a fibrosis score of F2 on the METAVIR scale, and three with cirrhosis (F4) at baseline. One year after the end of treatment, the hepatitis C viral load was undetectable in three of them. One patient was lost to follow-up after week 4. In two out of the four patients, a significant improvement and regression of liver fibrosis was observed (from stage F4 and F2 to F0-F1 on the METAVIR scale). In one patient, the liver stiffness measurement median increased 12 weeks after the end of the treatment and then decreased, but still correlated with stage F4. An improvement in the APRI was observed in all patients. In four patients without fibrosis, the treatment was effective and no progression of fibrosis was observed. A one-year observation of teenagers with CHC and significant fibrosis treated with LDV/SOF revealed that regression of liver fibrosis is possible, but not certain. Further observations in larger groups of patients are necessary to find predictors of liver fibrosis regression.
Cannabis and Inflammation in HIV: A Review of Human and Animal Studies
Authors: Ellis Ronald J. , Wilson Natalie , Peterson Scott
Published: August 2021

Persistent inflammation occurs in people with HIV (PWH) and has many downstream adverse effects including myocardial infarction, neurocognitive impairment and death. Because the proportion of people with HIV who use cannabis is high and cannabis may be anti-inflammatory, it is important to characterize the impact of cannabis use on inflammation specifically in PWH. We performed a selective, non-exhaustive review of the literature on the effects of cannabis on inflammation in PWH. Research in this area suggests that cannabinoids are anti-inflammatory in the setting of HIV. Anti-inflammatory actions are mediated in many cases through effects on the endocannabinoid system (ECS) in the gut, and through stabilization of gut–blood barrier integrity. Cannabidiol may be particularly important as an anti-inflammatory cannabinoid. Cannabis may provide a beneficial intervention to reduce morbidity related to inflammation in PWH.
The Algerian Chapter of SARS-CoV-2 Pandemic: An Evolutionary, Genetic, and Epidemiological Prospect
Authors: Zeghbib Safia , Somogyi Balázs A. , Zana Brigitta , Kemenesi Gábor , Herczeg Róbert , Derrar Fawzi , Jakab Ferenc
Published: August 2021

To explore the SARS-CoV-2 pandemic in Algeria, a dataset comprising ninety-five genomes originating from SARS-CoV-2 sampled from Algeria and other countries worldwide, from 24 December 2019, through 4 March 2021, was thoroughly examined. While performing a multi-component analysis regarding the Algerian outbreak, the toolkit of phylogenetic, phylogeographic, haplotype, and genomic analysis were effectively implemented. We estimated the Time to the Most Recent Common Ancestor (TMRCA) in reference to the Algerian pandemic and highlighted the multiple introductions of the disease and the missing data depicted in the transmission loop. In addition, we emphasized the significant role played by local and international travels in disease dissemination. Most importantly, we unveiled mutational patterns, the effect of unique mutations on corresponding proteins, and the relatedness regarding the Algerian sequences to other sequences worldwide. Our results revealed individual amino-acid replacements such as the deleterious replacement A23T in the orf3a gene in Algeria_EPI_ISL_418241. Additionally, a connection between Algeria_EPI_ISL_420037 and sequences originating from the USA was observed through a USA characteristic amino-acid replacement T1004I in the nsp3 gene, found in the aforementioned Algerian sequence. Similarly, successful tracing could be established, such as Algeria/G37318-8849/2020|EPI_ISL_766863, which was imported from Saudi Arabia during the pilgrimage. Lastly, we assessed the Algerian mitigation measures regarding disease containment using statistical analyses.
Usefulness of IVD Kits for the Assessment of SARS-CoV-2 Antibodies to Evaluate the Humoral Response to Vaccination
Authors: Lukaszuk Krzysztof , Kiewisz Jolanta , Rozanska Karolina , Dabrowska Malgorzata , Podolak Amira , Jakiel Grzegorz , Woclawek-Potocka Izabela , Lukaszuk Aron , Rabalski Lukasz
Published: August 2021

Background: The introduction of the vaccination against SARS-CoV-2 infection creates the need for precise tools for the quality control of vaccination procedures, detection of poor humoral response, and estimation of the achieved protection against the disease. Thus, the study aimed to compare the results of the anti-SARS-CoV-2 tests to evaluate the application of the WHO standard unitage (the binding antibody units; BAU/mL) for a measurement of response to the vaccination. Methods: Patients undergoing vaccination against SARS-CoV-2 with Pfizer/BioNTech BNT162b2 (BNT162b2) (n = 79), referred for SARS-CoV-2 antibody measurement prior to vaccination and 21 days after dose 1, and 8, 14, and 30 days after dose 2 were included. The sera were tested with three assays: Elecsys SARS-CoV-2 S (Roche), LIAISON® SARS-CoV-2 TrimericS IgG (DiaSorin), and SARS-CoV-2 IgG II Quant (Abbott). Results: The three assays showed varying correlations at different time points in the study. The overall agreement for all samples was moderate to high (ρ = 0.663–0.902). We observed the most uniform agreement for the day of dose 2 (ρ = 0.775–0.825), while it was least consistent for day 8 (ρ = −0.131–0.693) and 14 (ρ = −0.247–0.603) after dose 2. The dynamics of changes of the SARS-CoV-2 antibody levels in patients without history of prior SARS-CoV-2 infection appears homogenous based on the Roche results, more heterogenous when considering the DiaSorin results, and in between for the Abbott results. Conclusions: The results highlight the need for further work on the international standard of measurement of SARS-CoV-2 Ig, especially in the era of vaccination. The serological assays can be useful to detect IgG/IgM antibodies to assess the response to the vaccination. However, they cannot be used interchangeably. In terms of the evaluation of the immune response to the BNT162b2 vaccine, Roche and Abbott kits appear to be more useful.
Immunogenicity and Antiviral Response of Therapeutic Hepatitis B Vaccination in a Mouse Model of HBeAg-Negative, Persistent HBV Infection
Authors: Kosinska Anna D. , Festag Julia , Mück-Häusl Martin , Festag Marvin M. , Asen Theresa , Protzer Ulrike
Published: August 2021

During the natural course of chronic hepatitis B virus (HBV) infection, the hepatitis B e antigen (HBeAg) is typically lost, while the direct transmission of HBeAg-negative HBV may result in fulminant hepatitis B. While the induction of HBV-specific immune responses by therapeutic vaccination is a promising, novel treatment option for chronic hepatitis B, it remains unclear whether a loss of HBeAg may influence its efficacy or tolerability. We therefore generated an adeno-associated virus (AAV)-vector that carries a 1.3-fold overlength HBV genome with a typical stop-codon mutation in the pre-core region and initiates the replication of HBeAg(−) HBV in mouse livers. Infection of C57BL/6 mice established persistent HBeAg(−) HBV-replication without any detectable anti-HBV immunity or liver damage. HBV-carrier mice were immunized with TherVacB, a therapeutic hepatitis B vaccine that uses a particulate HBV S and a core protein for prime vaccination, and a modified vaccinia Ankara (MVA) for boost vaccination. The TherVacB immunization of HBeAg(+) and HBeAg(−) HBV carrier mice resulted in the effective induction of HBV-specific antibodies and the loss of HBsAg but only mild liver damage. Intrahepatic, HBV-specific CD8 T cells induced in HBeAg(−) mice expressed more IFNγ but showed similar cytolytic activity. This indicates that the loss of HBeAg improves the performance of therapeutic vaccination by enhancing non-cytolytic effector functions.
Parameterization of Pilot Point Methodology for Supplementing Sparse Transmissivity Data
Authors: Kapoor Aditya , Kashyap Deepak
Published: August 2021

Pilot point methodology (PPM) permits estimation of transmissivity at unsampled pilot points by solving the hydraulic head based inverse problem. Especially relevant to areas with sparse transmissivity data, the methodology supplements the limited field data. Presented herein is an approach for estimating parameters of PPM honoring the objectives of refinement of the transmissivity (T) interpolation and the model calibration. The parameters are the locations and number of pilot transmissivity points. The location parameter is estimated by defining a qualifying matrix Q comprising weighted sum of the hydraulic head-sensitivity and the kriging variance fields. Whereas the former component of Q promotes the model calibration, the latter one leads to improved T interpolation by locating pilot points in un-sampled tracts. Further, a three-stage methodology is proposed for an objective determination of the number of pilot points. It is based upon sequential upgradation of the Variogram as the pilot points are added to the data base, ensuring its convergence with the head-based optimal Variogram. The model has been illustrated by applying it to Satluj-Beas interbasin wherein the pumping test data is not only sparse, but also unevenly distributed.
The Spatial Variation Mechanism of Size, Velocity, and the Landing Angle of Throughfall Droplets under Maize Canopy
Authors: Zhu Zhongrui , Zhu Delan , Ge Maosheng
Published: August 2021

Larger diameter and velocity and smaller landing angle of sprinkler irrigation droplets are more likely to cause soil splash and erosion. However, the mechanism of crop canopy influence on the physical parameters of sprinkler droplets is unknown. In this study, with the landing angle of sprinkler irrigation droplets as the independent variable and maize plants (Zea mays L.) as the research object, an indoor sprinkler irrigation experiment was carried out. The effects of maize canopy and variation in sprinkler irrigation droplets landing angle on the value and spatial distribution pattern of size, the velocity, and the landing angle of throughfall droplets was analyzed. In addition, the spatial variation patterns of throughfall droplets size, velocities’ distribution, and individual droplet’s speed, kinetic energy were also explored. The results showed that maize canopy and the decreasing of the sprinkler irrigation droplet landing angle had a positive and obvious effect on reducing the size and velocity of penetrating rain droplets. However, the throughfall droplets’ landing angles were only small variations. When the landing angle of sprinkler irrigation droplets was >45°, the spatial distribution of throughfall droplets size and velocity corresponded well with the canopy structure and leaf projection area of maize, i.e., the further away from the maize stalk, the larger the size and velocity of throughfall droplets. Nevertheless, if the landing angle of sprinkler irrigation droplets was <45°, the spatial distribution mentioned above was mainly affected by droplets landing angle. The spatial variation of throughfall droplets’ size and velocities at different measurement points was attributed to the change of the larger droplets’ volume proportion and the equivalent velocity. Although the maize leaves had a certain degree of perturbation effect on the velocities and kinetic energy of the larger kinetic energy droplets, the flight path of these drops did not alter significantly. The results of this research will be of practical value in guiding the development of a new sprayer and the optimum selection of sprinkler heads.
Application of the Kilimanjaro Concept in Reversing Seawater Intrusion and Securing Water Supply in Zanzibar, Tanzania
Authors: Pembe-Ali Zuleikha , Mwamila Tulinave Burton , Lufingo Mesia , Gwenzi Willis , Marwa Janeth , Rwiza Mwemezi J. , Lugodisha Innocent , Qi Qinwen , Noubactep Chicgoua
Published: August 2021

There is escalating salinity levels on small islands due to uncontrolled groundwater extraction. Conventionally, this challenge is addressed by adopting optimal groundwater pumping strategies. Currently, on Unguja Island (Zanzibar), urban freshwater is supplied by desalination, which is expensive and energy-intensive. Hence, desalinization cannot be afforded by rural communities. This study demonstrates that the innovative Kilimanjaro Concept (KC), based on rainwater harvesting (RWH) can remediate seawater intrusion in Unguja, while enabling a universal safe drinking water supply. The reasoning is rooted in the water balance of the whole island. It is shown that if rainwater is systematically harvested, quantitatively stored, and partly infiltrated, seawater intrusion will be reversed, and a universal safe drinking water supply will be secured. Water treatment with affordable technologies (e.g., filtration and adsorption) is suggested. The universality of KC and its suitability for small islands is demonstrated. Future research should focus on pilot testing of this concept on Unguja Island and other island nations.
Spatiotemporal Hotspots and Decadal Evolution of Extreme Rainfall-Induced Landslides: Case Studies in Southern Taiwan
Authors: Wu Chunhung , Lin Chengyi
Published: August 2021

The 2009 Typhoon Morakot triggered numerous landslides in southern Taiwan, and the landslide ratios in the Ailiao and Tamali river watershed were 7.6% and 10.7%, respectively. The sediment yields from the numerous landslides that were deposited in the gullies and narrow reaches upstream of Ailiao and Tamali river watersheds dominated the landslide recovery and evolution from 2010 to 2015. Rainfall records and annual landslide inventories from 2005 to 2015 were used to analyze the landslide evolution and identify the landslide hotspots. The landslide recovery time in the Ailiao and Tamali river watershed after 2009 Typhoon Morakot was estimated as 5 years after 2009 Typhoon Morakot. The landslide was easily induced, enlarged, or difficult to recover during the oscillating period, particularly in the sub-watersheds, with a landslide ratio > 4.4%. The return period threshold of rainfall-induced landslides during the landslide recovery period was <2 years, and the landslide types of the new or enlarged landslide were the bank-erosion landslide, headwater landslide, and the reoccurrence of old landslide. The landslide hotspot areas in the Ailiao and Tamali river watershed were 2.67–2.88 times larger after the 2009 Typhoon Morakot using the emerging hot spot analysis, and most of the new or enlarged landslide cases were identified into the oscillating or sporadic or consecutive landslide hotspots. The results can contribute to developing strategies of watershed management in watersheds with a dense landslide.
Investigating Effect of Pumping Ratio on Effectiveness of Barrier Wells for Saltwater Intrusion: Lab-Scale Experiments and Numerical Modeling
Authors: Ozaki Shinichi , Akl Christel Abi , Nagino Tatsuya , Hiroshiro Yoshinari
Published: August 2021

Saltwater intrusion, leading to the salinization of fresh groundwater, is the most challenging problem in coastal regions. Saltwater pumping from a barrier well is widely applied to prevent saltwater intrusion. Owing to its easy installation, many studies have investigated saltwater pumping. However, quantitative relationships between the barrier and inland production wells have not been revealed. In this study, lab-scale experiments were conducted to examine the effectiveness of a barrier well on the possible flow rate of freshwater from a production well. Moreover, a two-dimensional numerical model was created and simulated under the same conditions as those used in the experiments to analyze the experimental results. Consequently, a critical pumping ratio of 1.9 was obtained. In the numerical simulation, it was confirmed that an upconing of highly concentrated saltwater toward the barrier well was observed when the pumping ratio was less than the critical ratio. In conclusion, there is a critical pumping ratio between the barrier and the production well, and saltwater intrusion can be controlled by keeping the pumping rates under the critical ratio. Although further studies have yet to be conducted on a practical scale, this study showed the potential of the pumping ratio control to manage saltwater intrusion.
Water Temperature and Hydrological Modelling in the Context of Environmental Flows and Future Climate Change: Case Study of the Wilmot River (Canada)
Authors: Charron Christian , St-Hilaire André , Ouarda Taha B.M.J. , van den Heuvel Michael R.
Published: August 2021

Simulation of surface water flow and temperature under a non-stationary, anthropogenically impacted climate is critical for water resource decision makers, especially in the context of environmental flow determination. Two climate change scenarios were employed to predict streamflow and temperature: RCP 8.5, the most pessimistic with regards to climate change, and RCP 4.5, a more optimistic scenario where greenhouse gas emissions peak in 2040. Two periods, 2018–2050 and 2051–2100, were also evaluated. In Canada, a number of modelling studies have shown that many regions will likely be faced with higher winter flow and lower summer flows. The CEQUEAU hydrological and water temperature model was calibrated and validated for the Wilmot River, Canada, using historic data for flow and temperature. Total annual precipitation in the region was found to remain stable under RCP 4.5 and increase over time under RCP 8.5. Median stream flow was expected to increase over present levels in the low flow months of August and September. However, increased climate variability led to higher numbers of periodic extreme low flow events and little change to the frequency of extreme high flow events. The effective increase in water temperature was four-fold greater in winter with an approximate mean difference of 4 °C, while the change was only 1 °C in summer. Overall implications for native coldwater fishes and water abstraction are not severe, except for the potential for more variability, and hence periodic extreme low flow/high temperature events.
Design of Land Application Systems for Water Reuse
Authors: Fedler Clifford B.
Published: August 2021

Water reuse via land application is old technology; but the water balance only design approach and practice has not worked well. There are many benefits of water reuse by irrigating crops; however, there are some risks if not designed properly. When the design approach uses a combined water-nutrient-salt balance, the most effective and sustainable, long-term system is achieved. This approach provides a design based on land area requirements, on-site water storage, and economic return from the irrigated crops. The single, most often overlooked step in the water balance is accounting for the water stored in the soil. When spread over large areas, this quantity of water results in considerably less required surface water storage, which saves capital costs. This design approach has been used successfully on multiple sites for over 30 years without failure.
Change in Fuel Consumption of a Hybrid Vehicle When Operating in the Far North
Authors: Shvetsov Alexey V.
Published: August 2021

This paper studies the effect of extremely low outdoor temperatures (−40...−50 °C) on the increase in fuel consumption of a passenger car with a hybrid powertrain when operating in the far north regions. The experiment was carried out in the climatic conditions of the far north ern territory of the city of Yakutsk, Russia (Russian Federation). At the first stage of the experiment, data on fuel consumption of a hybrid vehicle in the summer season at an outdoor temperature in the range of +20...+30 °C were obtained. At the second stage of the experiment, data on fuel consumption of a hybrid vehicle in the winter season at extremely low outdoor temperatures in the range of −40...−50 °C were obtained. As a result, by comparing the fuel consumption data obtained in the first and second stages of the experiment, data on the effect of extremely low outdoor temperatures on fuel consumption of a hybrid vehicle were obtained. The obtained data may be of interest to manufacturers of hybrid vehicles, as well as to consumers of their products, including taxi services and individual car owners living (working) in the northern regions of the planet.
Economic and biological value of pea varieties in solving the protein problem under environment the Trans-Urals
Authors: Porsev I. N. , Viyunik A. V. , Polovnikova V. V. , Andreeva O. A.
Published: August 2021

Under the conditions of the Trans-Urals the cultivation of varieties of field pea allows us to get high yields, not inferior to grain, provides high profitability and solves the problem of protein in animal husbandry. Its inclusion in the crop rotation contributes to the improvement of soil fertility, yield and product quality of subsequent crops. Pea seeds depending on the variety and cultivation conditions contain (in % per dry matter): 9–15 water, 18–35 protein, 46–60 nitrogen-free extractives (including 20–50 % starch, 4–10 % sugars), 0,6–1,5 fat, 2–10 fiber, 2–4 ash. The purpose of the research was to determine the economic and biological value of varieties of field pea and the influence of biotic and abiotic factors on crop yield under the conditions of the Trans-Urals. According to the results of three years of study a good level of yield was noted in the varieties recommended for cultivation in the Ural region, which includes the Kurgan region: Aksaysky Usaty 55–2,47 t/ha; Agrointel – 1,88 t/ha, Zauralsky 3–2,12 t/ha, Samarius – 2,40 t/ha. Among the new varieties the high yield was shown by the varieties Kulon – 2,75 t/ha, Yamal 305–1,94 t/ha, Chevron – 1,84 t/ha. The increase in the seed yield of pea varieties with the use of urea (N₃₀) was noted for all the studied varieties. So, for example, for Sibur 2 variety by 1,11 times, for Aksaysky Usaty 55 and Samat varieties by 1,12, for Samarius variety by 1,15 times. The use of urea and double superphosphate (N₃₀P₃₀) to obtain the maximum yield for the studied varieties of peas allowed to increase the yield for the variety Aksaysky Usaty 55 by 1,18 times, Samat and Sibur 2 by 1,17, Samarius by 1,2 times.