bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Government Subsidy Strategies for the Development of Agricultural Products E-Commerce
Authors: Zhong Yaoguang , Lai Ivan Ka Wai , Guo Fangfang , Tang Huajun
Published: November 2021

In many countries, the governments support the development of local agriculture through subsidization. Subsidizing the sales of agricultural products through E-commerce channels is a way to support the development of agriculture in China. This study aims to develop a profit model and apply Stackelberg game theory to determine which type of subsidies and decision-making can provide the maximum benefits for agricultural products E-commerce supply chains. The results indicate that for both centralized decisions and decentralized decisions, the subsidizing to the agricultural cooperative is better than the subsidizing to consumers and no subsidization. The sales volume, preservation level, sales efforts, and overall profit of the agricultural products E-commerce supply chain are significantly higher. It suggests that the government should play a leading role to support the development of agricultural products E-commerce. This study contributes to agricultural research by developing a profit model to examine the effects of different government subsidy strategies on each member of the agricultural online shopping supply chain. Recommendations are provided for agricultural cooperatives, E-commerce platforms, and the government to improve the quality and sales of agricultural products through online shopping channels.
Field Study of the Effects of Two Different Environmental Conditions on Wheat Productivity and Chlorophyll Fluorescence Induction (OJIP) Parameters
Authors: Spanic Valentina , Mlinaric Selma , Zdunic Zvonimir , Katanic Zorana
Published: November 2021

Wheat is one of the main cereal crops for ensuring food supply. Thus, increasing grain yield is a major target for plant breeders, where insights into wheat productivity can be gained by studying the activity of the components of photosynthetic apparatus. The objectives of this study were to evaluate the agronomical performance of three winter wheat varieties and test photosynthetic efficiency over two different locations. Chlorophyll fluorescence was used to evaluate the maximum quantum yield of photosystem II (PSII) (TR0/ABS) and performance index on absorption basis (PIabs) of flag leaves and glumes of heads at the flowering stage until the mid-senescence stage. The grain yield of all varieties on average was significantly higher at Osijek compared to Tovarnik. Variety Tika Taka exhibited the highest yield reduction (27.1%) at Tovarnik compared to Osijek, followed by El Nino (20.5%) and Vulkan (18.7%), respectively. A higher amount of precipitation in June at Tovarnik provoked higher Fusarium head blight disease intensity, which could be seen as the bleaching of plant heads at the plots and resulted in an earlier decrease in photosynthetic activity. Therefore, earlier senescence and contracted grain fill duration could occur.
Perceptions of Smallholder Farmers towards Organic Farming in South Africa
Authors: Uhunamure Solomon Eghosa , Kom Zongho , Shale Karabo , Nethengwe Nthaduleni Samuel , Steyn Jacobus
Published: November 2021

In South Africa, smallholder farming is an important aspect of livelihood. More so, organic farming is increasingly becoming popular among farmers. However, many studies undertaken focused on the trade possibilities of the industry leaving the farmers’ perceptions underrepresented. This study, therefore, aims to capture the farmers’ opinions by evaluating the critical factors and policy implications of organic farming in the Limpopo Province of South Africa. A total of 220 semi-structured questionnaires were administered to smallholder farmers in the province. The results revealed that organic farming is gaining recognition according to 82.8% of the participants, and 86.6% believed that organic farming has high-profit returns. However, 88.4% of the respondents agreed that the required standards for organic farming are too restrictive while a further 74.6% indicated that organic farming certification is difficult to obtain. The results also indicated a statistically significant difference in the perceived benefits of organic farming (p ≤ 0.001) and access to markets (p = 0.042). Based on the results, the study suggests more awareness, training and ease of certification as a way forward in changing the perceptions of the farmers in the province.
Influence of Calving Ease on In-Line Milk Urea and Relationship with Other Milk Characteristics in Dairy Cows
Authors: Televičius Mindaugas , Antanaitis Ramūnas , Juozaitienė Vida , Paulauskas Algimantas , Malašauskienė Dovilė , Urbutis Mingaudas , Baumgartner Walter
Published: November 2021

The aim of this research was to identify the relationship of calvin ease and level of in-line milk urea (MU) and other milk components, namely milk yield (MY), electrical conductivity (EC), milk fat (MF), milk protein (MP), milk fat/protein ratio (MF/MP), and somatic cell count (SCC) in dairy cows. The cows for the research were selected following such criteria: cows were tested within the period of up to the first 30 days after calving and had had a range of lactation numbers from two to four. Each selected farm housed more than 500 dairy cows and a total of 4712 calving cases from the eight dairy farms were studied and evaluated. The 4-point scale was used for the evaluation of the calving according to the point value meanings where 1 = easy, unassisted; 2 = easy, assisted; 3 = difficult, assisted; 4 = difficult, requiring veterinary intervention. A total of 4712 calving cases were researched and scored. The chemical properties of milk in all research cows were analyzed during the early phase of lactation (from the onset of calving to 30 days past calving) every day, during each milking. Cows were classified into groups according to the level of urea in milk: Group 1 had MU ≤ 15 mg/dL (12.6% of cows), Group 2 had MU 16–30 mg/dL (62.4% of cows), and Group 3 had MU > 30 mg/dL (25.0% of cows). We found that cows with milk urea levels between 16 and 30 mg/dL had the lowest incidence of dystocia, and also the highest concentration of milk lactose (ML ≥ 4.6%), the lowest mean value of milk electrical conductivity, and the lowest value of milk SCC. Dystocia increased the risk of somatic cell growth in cow’s milk above the herd average (OR = 1.364; 95% CI = 1.184–1.571, p < 0.001), and normal urea in milk reduced this risk (OR = 0.749; 95% CI = 0.642–0.869, p = 0.05). In all groups of cows, according to the level of urea in milk, the productivity of cows without dystocia at calving was higher (2.50–5.51 kg) as well as the milk protein % (0.13–0.21%) and milk lactose % (0.07–0.19%). We concluded that, in all groups of cows, according to the level of urea in milk, the productivity and milk lactose concentration of cows without dystocia at calving was higher, and lower somatic cells count and electrical conductivity values were found in the milk compared with cows diagnosed with dystocia at calving. We can state that dystocia has a negative effect on milk urea concentration and can increase the risk of mastitis.
Physiology, Growth, and Productivity of Spring–Summer Black Gram (Vigna mungo L. Hepper) as Influenced by Heat and Moisture Stresses in Different Dates of Sowing and Nutrient Management Conditions
Authors: Banerjee Purabi , Venugopalan Visha Kumari , Nath Rajib , Althobaiti Yusuf S. , Gaber Ahmed , Al-Yasi Hatim , Hossain Akbar
Published: November 2021

Heat and soil moisture stress account for serious abiotic constraint in black gram (Vigna mungo (L.) Hepper) production during spring–summer under Gangetic plains of Eastern India. Concurrence of these two can bring about early completion of phenophases that hampers normal metabolism of legumes by disrupting their defense mechanism, leading to poor seed set. The field experiment was conducted with two different sowing dates as the main plot, soil application of cobalt (Co) as subplots and foliar sprays of potassium (K) and boron (B) either alone or in combination as sub–sub plot treatment in a split–split plot design during spring–summer seasons of 2020 and 2021 with black gram (variety: Pant U 31). The study was aimed at evaluating the impact of sowing time and nutrients application alleviating adversities of abiotic stress during reproductive development of black gram. The March first week sown crop took significantly higher days to complete its life cycle compared to March third week sown one (82.0 vs. 78.2 and 81.8 vs. 78.8). This in turn relatively allowed a broader window for leaf area expansion, flowering, and seed filling in the first crop compared to the second one leading to the attainment of superior yield in the normal sown crop during the consecutive years. Crop growth rate (CGR), net assimilation rate (NAR), pod number per plant, seed yield, and harvest index were significantly higher (p ≤ 0.05) with soil Co @ 4 kg ha−1 and foliar 1.25% K + 0.2% B applications through stress mitigation by stimulating chlorophyll biosynthesis, nitrate reductase activity, proline accumulation, and cell membrane stability, irrespective of the years. Fluctuations in per plant pod number explained about 96 and 94% variations in seed yield through linear regressions in respective years. Optimum sowing date along with soil Co application combined with foliar K+B sprays manifested immense potential to achieve higher black gram production. In addition, this nutrient schedule proved to be efficient enough to promote satisfactory growth and optimum seed yield of late sown blackgram through relief of stress during the spring–summer season.
Modelling the Effect and Variability of Integrated Weed Management of Phalaris minor in Rice-Wheat Cropping Systems in Northern India
Authors: Liu Chun , Bhullar Makhan Singh , Kaur Tarundeep , Kumar Jitendra , Reddy Sriyapu Reddy Sreekanth , Singh Manpreet , Kaundun Shiv Shankhar
Published: November 2021

Phalaris minor Retz. (littleseed canarygrass) is the most problematic and herbicide-resistant weed in the rice-wheat cropping system in India. As such, it poses a severe threat to wheat yield and food security. A number of herbicidal and agronomic practices have been identified for the effective control of P. minor. These include crop rotation, crop establishment methods, herbicide spray technology, sowing time, weed seed harvest and effective herbicide mixtures. A population model of P. minor was built based on the life cycle of the species, herbicide resistance mechanisms and the effects of weed control practices. The model simulated the interactions of these factors and provided the best management recommendations for sustainably controlling this noxious weed species. Model results indicate that integration of chemical and non-chemical control methods was the most effective and sustainable strategy. For example, the integration of a happy seeder (a tractor-mounted mulching and sowing machine) with an effective post-emergence herbicide reduced the probability of weed control failure by 32% compared to the scenario with a rotavator and the same herbicide. Similarly, more conventional crop establishment methods such as a rotavator and conventional tillage could be accompanied by pre- or post-emergence applications of herbicide mixtures. Adoption of good herbicide spray technology and weed seed harvest delayed the onset of resistance evolution by up to four years. Furthermore, effective crop rotation such as the inclusion of sugarcane in place of rice in the summer season reduced the risk of resistance evolution by 31% within the 10 year simulation period. In addition to the scenarios using representative parameter values, the variability of model predictions was investigated based on some field experiments. The model provided a powerful tool for promoting Integrated Weed Management and the sustainable use of herbicides. Pragmatic ways of dealing with uncertainty in model prediction are discussed.
Estimation of Evapotranspiration and Crop Coefficient of Rain-Fed Tea Plants under a Subtropical Climate
Authors: Zheng Shenghong , Ni Kang , Ji Lingfei , Zhao Chenguang , Chai Hongling , Yi Xiaoyun , He Weizhong , Ruan Jianyun
Published: November 2021

Crop coefficient (Kc) is one of the most significant parameters for crop water demand prediction and irrigation scheduling. However, there is a lack of knowledge about water vapor and Kc in tea plantation ecosystems. This study explored and determined the actual evapotranspiration (ETc) and Kc of two cultivars of tea (Camellia sinensis), clone variety Baiye1 (BY1) and Longjing43 (LJ43), based on lysimeter data. An estimation was made for both for ETc and adjusted ETc, and the corresponding Kc and adjusted Kc. The results showed that the adjusted ETc and Kc values revealed a minor fluctuation when compared to the ETc and Kc values during the experimental period, which indicated that the adjusted ETc and Kc values were more precise and practical to field conditions. The average adjusted Kc values were 0.71 (range of 0.43–1.02) for BY1 and 0.84 (range of 0.48–1.22) for LJ43. Additionally, heavy pruning can decrease ETc and Kc values, possibly due to the lower level of LAI after pruning. Moreover, it is clearly manifested that BY1 consistently had lower ETc and Kc values than those of LJ43 because of plant growth status differences between BY1 and LJ43. Overall, our study proposed a reliable reference of Kc in tea plantation, and illuminated the effects of pruning and plant growth differences on Kc, which could provide a strong basis for precise irrigation in tea plantations in a subtropical climate.
Cd and Zn Concentrations in Soil and Silage Maize following the Addition of P Fertilizer
Authors: Niño-Savala Andrea Giovanna , Weishaar Benedikt , Franzaring Jürgen , Liu Xuejun , Fangmeier Andreas
Published: November 2021

Studies of soil Cd and Zn are often performed on sites that are contaminated or have deficient Zn conditions. Soil characteristics and crop management could impact the soil mobility and uptake of Cd and Zn, even when considering unpolluted Cd soils and adequate soil Zn levels. The concentrations of these two metals were assessed in soil and silage maize under five P fertilization treatments at two growth stages under low Cd and sufficient Zn conditions. Pearson correlation coefficients and stepwise linear regressions were calculated to investigate the soil characteristics influencing the bioavailable metal fraction in soil and the metal concentration in silage maize. P treatments did not impact Cd accumulation in maize; however, the Zn uptake was affected by P placement at the leaf development stage. From early development to maturity, the Cd level in maize decreased to 10% of the initial uptake, while the Zn level decreased to 50% of the initial uptake. This reduction in both metals may be attributed to a dilution effect derived from high biomass production. Silage maize could alleviate the initial Cd uptake while diminishing the depressant effect of P fertilizer on Zn concentration. Further research is required to understand the effect of P fertilizer on Cd uptake and its relation to Zn under field conditions at early and mature stages.
Molecular Detection and Characterization of Intestinal and Blood Parasites in Wild Chimpanzees (Pan troglodytes verus) in Senegal
Authors: Köster Pamela C. , Renelies-Hamilton Justinn , Dotras Laia , Llana Manuel , Vinagre-Izquierdo Celia , Prakas Petras , Sneideris Donatas , Dashti Alejandro , Bailo Begoña , Lanza Marta , Jiménez-Mejías Alejandra , Muñoz-García Carlota , Muadica Aly S. , González-Barrio David , Rubio José M. , Fuentes Isabel , Ponce-Gordo Francisco , Calero-Bernal Rafael , Carmena David
Published: November 2021

Wild chimpanzee populations in West Africa (Pan troglodytes verus) have dramatically decreased as a direct consequence of anthropogenic activities and infectious diseases. Little information is currently available on the epidemiology, pathogenic significance, and zoonotic potential of protist species in wild chimpanzees. This study investigates the occurrence and genetic diversity of intestinal and blood protists as well as filariae in faecal samples (n = 234) from wild chimpanzees in the Dindefelo Community Nature Reserve, Senegal. PCR-based results revealed the presence of intestinal potential pathogens (Sarcocystis spp.: 11.5%; Giardia duodenalis: 2.1%; Cryptosporidium hominis: 0.9%), protist of uncertain pathogenicity (Blastocystis sp.: 5.6%), and commensal species (Entamoeba dispar: 18.4%; Troglodytella abrassarti: 5.6%). Entamoeba histolytica, Enterocytozoon bieneusi, and Balantioides coli were undetected. Blood protists including Plasmodium malariae (0.4%), Trypanosoma brucei (1.3%), and Mansonella perstans (9.8%) were also identified. Sanger sequencing analyses revealed host-adapted genetic variants within Blastocystis, but other parasitic pathogens (C. hominis, P. malariae, T. brucei, M. perstans) have zoonotic potential, suggesting that cross-species transmission between wild chimpanzees and humans is possible in areas where both species overlap. Additionally, we explored potential interactions between intestinal/blood protist species and seasonality and climate variables. Chimpanzees seem to play a more complex role on the epidemiology of pathogenic and commensal protist and nematode species than initially anticipated.
Modulation of Intestinal Histology by Probiotics, Prebiotics and Synbiotics Delivered In Ovo in Distinct Chicken Genotypes
Authors: Bogusławska-Tryk Monika , Ziółkowska Ewa , Sławińska Anna , Siwek Maria , Bogucka Joanna
Published: November 2021

The aim of the study was to determine the effect of probiotics, prebiotics and synbiotics administered in ovo on selected morphological parameters of the small intestine (duodenum, jejunum, ileum) in broiler chickens (Ross 308) and native chickens (Green-legged Partridge, GP). On the 12th day of embryonic development (the incubation period), an aqueous solution of a suitable bioactive substance was supplied in ovo to the egg’s air cell: probiotic—Lactococcus lactis subsp. cremoris (PRO), prebiotic—GOS, galacto-oligosaccharides (PRE) or symbiotic—GOS + Lactococcus lactis subsp. cremoris (SYN). Sterile saline was injected into control (CON) eggs. After hatching, the chicks were placed in pens (8 birds/pen, 4 replicates/group) and housed for 42 days. On the last day of the experiment, all birds were individually weighed and slaughtered. Samples for histological analysis were taken directly after slaughter from three sections of the small intestine. In samples from the duodenum, jejunum and ileum, the height and width of the intestinal villi (VH) were measured and their area (VA) was calculated, the depth of the intestinal crypts (CD) was determined, the thickness of the muscularis was measured and the ratio of the villus height to the crypt depth (V/C) was calculated. On the basis of the obtained data, it can be concluded that the applied substances administered in ovo affect the production parameters and intestinal morphology in broiler chickens and GP. The experiment showed a beneficial effect of in ovo stimulation with a prebiotic on the final body weight of Ross 308 compared to CON, while the effect of the administered substances on the intestinal microstructure is not unequivocal. In GP, the best effect in terms of villi height and V/C ratio was found in the in ovo synbiotic group. Taking into account the obtained results, it can be concluded that chickens of different genotypes react differently to a given substance; therefore, the substances should be adapted to the genotype.
Histidine Promotes the Glucose Synthesis through Activation of the Gluconeogenic Pathway in Bovine Hepatocytes
Authors: Yang Tianyu , Cheng Zhiqiang , Jiang Maocheng , Ma Xiaoyu , Datsomor Osmond , Zhao Guoqi , Zhan Kang
Published: November 2021

Histidine (His) is considered to be the first-limiting amino acid (AA) on grass silage-based diets in lactation cows, which correlate positively with lactose yield. The higher glucose requirements of lactating cows can be met through a combination of increased capacity for gluconeogenesis and increased supply of gluconeogenic precursors. However, the effect of His on the expression of gluconeogenic genes in the bovine hepatocytes is less known. Therefore, this study aimed to investigate the regulatory effect of His on the key gluconeogenic genes and glucose output in bovine hepatocytes. The addition of 0.15, 0.6, and 1.2 mM His in a medium significantly enhanced (p < 0.05) the viability of bovine hepatocytes. Remarkably, 1.2 mM His induced profound changes (p < 0.05) in the mRNA level of key genes involved in gluconeogenesis, including PCK1, PCK2, FBP1, and G6PC in vitro. Furthermore, the mRNA expression of PCK1 was significantly elevated (p < 0.05) by the addition of 1.2 mM His at 3, 6, 12, and 24 h of incubation. The hepatic glucose output increased (p < 0.05) linearly with increasing His concentration. These findings indicate that the addition of His may be efficiently converted into glucose via the upregulation of genes related to the gluconeogenic pathway.
Aujeszky’s Disease in South-Italian Wild Boars (Sus scrofa): A Serological Survey
Authors: Ferrara Gianmarco , Longobardi Consiglia , D’Ambrosi Filomena , Amoroso Maria Grazia , D’Alessio Nicola , Damiano Sara , Ciarcia Roberto , Iovane Valentina , Iovane Giuseppe , Pagnini Ugo , Montagnaro Serena
Published: November 2021

Aujeszky’s disease (AD, pseudorabies) is a viral disease of suids caused by Suid Herpesvirus 1 (SHV-1) also referred as Aujeszky’s disease virus (ADV) or Pseudorabies virus (ADV). Domestic pig and Wild boar (Sus scrofa) are the natural host, but many species can be infected with ADV. The aim of our study was to evaluate seroprevalence of AD in wild boar hunted in the Campania Region, during the 2016–2017 hunting season. A total of 503 serum samples from wild boars hunted in the provinces of Campania Region (Southern Italy) were collected and were tested for antibody against ADV using an AD, blocking ELISA assay. A Seroprevalence of 23.85% (120/503, 95% Confidence Interval (CI): 20.15–27.55) was found. Gender was not significantly associated with of ADV seropositivity (p > 0.05), while the presence of ADV antibodies was statistically associated with age (>36-month, p < 0.0001) and location (Avellino, p = 0.0161). Our prevalence values are like those obtained in 2010 in our laboratory (30.7%), demonstrating a constant circulation of ADV in the area.
Settle Down! Ranging Behaviour Responses of Roe Deer to Different Capture and Release Methods
Authors: Bergvall Ulrika A. , Morellet Nicolas , Kjellander Petter , Rauset Geir R. , Groeve Johannes De , Borowik Tomasz , Brieger Falko , Gehr Benedikt , Heurich Marco , Hewison A.J. Mark , Kröschel Max , Pellerin Maryline , Saïd Sonia , Soennichsen Leif , Sunde Peter , Cagnacci Francesca
Published: November 2021

The fitting of tracking devices to wild animals requires capture and handling which causes stress and can potentially cause injury, behavioural modifications that can affect animal welfare and the output of research. We evaluated post capture and release ranging behaviour responses of roe deer (Capreolus capreolus) for five different capture methods. We analysed the distance from the centre of gravity and between successive locations, using data from 14 different study sites within the EURODEER collaborative project. Independently of the capture method, we observed a shorter distance between successive locations and contextual shift away from the home range centre of gravity after the capture and release event. However, individuals converged towards the average behaviour within a relatively short space of time (between 10 days and one month). If researchers investigate questions based on the distance between successive locations of the home range, we recommend (1) initial investigation to establish when the animals start to behave normally again or (2) not using the first two to three weeks of data for their analysis. We also encourage researchers to continually adapt methods to minimize stress and prioritize animal welfare wherever possible, according to the Refinement of the Three R’s.
High Genomic Identity between Clinical and Environmental Strains of Herbaspirillum frisingense Suggests Pre-Adaptation to Different Hosts and Intrinsic Resistance to Multiple Drugs
Authors: Oliveira Willian Klassen , Ávila Hugo Leonardo , Tadra Michelle Zibeti , Cardoso Rodrigo Luiz , Fadel-Pichet Cyntia Maria Teles , de Souza Emanuel Maltempi , de Oliveira Pedrosa Fábio , Faoro Helisson
Published: November 2021

The genus Herbaspirillum is widely studied for its ability to associate with grasses and to perform biological nitrogen fixation. However, the bacteria of the Herbaspirillum genus have frequently been isolated from clinical samples. Understanding the genomic characteristics that allow these bacteria to switch environments and become able to colonize human hosts is essential for monitoring emerging pathogens and predicting outbreaks. In this work, we describe the sequencing, assembly, and annotation of the genome of H. frisingense AU14559 isolated from the sputum of patients with cystic fibrosis, and its comparison with the genomes of the uropathogenic strain VT-16–41 and the environmental strains GSF30, BH-1, IAC152, and SG826. The genes responsible for biological nitrogen fixation were absent from all strains except for GSF30. On the other hand, genes encoding virulence and host interaction factors were mostly shared with environmental strains. We also identified a large set of intrinsic antibiotic resistance genes that were shared across all strains. Unlike other strains, in addition to unique genomic islands, AU14559 has a mutation that renders the biosynthesis of rhamnose and its incorporation into the exopolysaccharide unfeasible. These data suggest that H. frisingense has characteristics that provide it with the metabolic diversity needed to infect and colonize human hosts.
Influence of Phenolic-Food Matrix Interactions on In Vitro Bioaccessibility of Selected Phenolic Compounds and Nutrients Digestibility in Fortified White Bean Paste
Authors: Sęczyk Łukasz , Gawlik-Dziki Urszula , Świeca Michał
Published: November 2021

This model study aimed to evaluate the effect of phenolic–food matrix interactions on the in vitro bioaccessibility and antioxidant activity of selected phenolic compounds (gallic acid, ferulic acid, chlorogenic acid, quercetin, apigenin, and catechin) as well as protein and starch digestibility in fortified white bean paste. The magnitude of food matrix effects on phenolics bioaccessibility and antioxidant activity was estimated based on “predicted values” and “combination indexes”. Furthermore, the protein–phenolics interactions were investigated using electrophoretic and chromatographic techniques. The results demonstrated phenolic–food matrix interactions, in most cases, negatively affected the in vitro bioaccessibility and antioxidant activity of phenolic compounds as well as nutrient digestibility. The lowest in vitro bioaccessibility of phenolic compounds in fortified paste was found for quercetin (45.4%). The most negative impact on the total starch digestibility and relative digestibility of proteins was observed for catechin–digestibility lower by 14.8%, and 21.3% (compared with control), respectively. The observed phenolic–food matrix interactions were strictly dependent on the applied phenolic compound, which indicates the complex nature of interactions and individual affinity of phenolic compounds to food matrix components. In conclusion, phenolic–food matrix interactions are an important factor affecting the nutraceutical and nutritional potential of fortified products.
A Performance–Consumption Balanced Scheme of Multi-Hop Quantum Networks for Teleportation
Authors: Xu Jin , Chen Xiaoguang , Xiao Hanwei , Wang Pingxun , Ma Mingzi
Published: November 2021

Teleportation is an important protocol in quantum communication. Realizing teleportation between arbitrary nodes in multi-hop quantum networks is of great value. Most of the existing multi-hop quantum networks are based on Bell states or Greeberger–Horne–Zeilinger (GHZ) states. Bell state is more susceptible to noise than GHZ states after purification, but generating a GHZ state consumes more basic states. In this paper, a new quantum multi-hop network scheme is proposed to improve the interference immunity of the network and avoid large consumption at the same time. Teleportation is realized in a network based on entanglement swapping, fusion, and purification. To ensure the robustness of the system, we also design the purification algorithm. The simulation results show the successful establishment of entanglement with high fidelity. Cirq is used to verify the network on the Noisy Intermediate-Scale Quantum (NISQ) platform. The robustness of the fusion scheme is better than the Bell states scheme, especially with the increasing number of nodes. This paper provides a solution to balance the performance and consumption in a multi-hop quantum network.
Applications of Multi-Agent Deep Reinforcement Learning: Models and Algorithms
Authors: Ibrahim Abdikarim Mohamed , Yau Kok-Lim Alvin , Chong Yung-Wey , Wu Celimuge
Published: November 2021

Recent advancements in deep reinforcement learning (DRL) have led to its application in multi-agent scenarios to solve complex real-world problems, such as network resource allocation and sharing, network routing, and traffic signal controls. Multi-agent DRL (MADRL) enables multiple agents to interact with each other and with their operating environment, and learn without the need for external critics (or teachers), thereby solving complex problems. Significant performance enhancements brought about by the use of MADRL have been reported in multi-agent domains; for instance, it has been shown to provide higher quality of service (QoS) in network resource allocation and sharing. This paper presents a survey of MADRL models that have been proposed for various kinds of multi-agent domains, in a taxonomic approach that highlights various aspects of MADRL models and applications, including objectives, characteristics, challenges, applications, and performance measures. Furthermore, we present open issues and future directions of MADRL.
Building and Evaluating an Annotated Corpus for Automated Recognition of Chat-Based Social Engineering Attacks
Authors: Tsinganos Nikolaos , Mavridis Ioannis
Published: November 2021

Chat-based Social Engineering (CSE) is widely recognized as a key factor to successful cyber-attacks, especially in small and medium-sized enterprise (SME) environments. Despite the interest in preventing CSE attacks, few studies have considered the specific features of the language used by the attackers. This work contributes to the area of early-stage automated CSE attack recognition by proposing an approach for building and annotating a specific-purpose corpus and presenting its application in the CSE domain. The resulting CSE corpus is then evaluated by training a bi-directional long short-term memory (bi-LSTM) neural network for the purpose of named entity recognition (NER). The results of this study emphasize the importance of adding a plethora of metadata to a dataset to provide critical in-context features and produce a corpus that broadens our understanding of the tactics used by social engineers. The outcomes can be applied to dedicated cyber-defence mechanisms utilized to protect SME employees using Electronic Medium Communication (EMC) software.
SMM: Leveraging Metadata for Contextually Salient Multi-Variate Motif Discovery
Authors: Poccia Silvestro R. , Candan K. Selçuk , Sapino Maria Luisa
Published: November 2021

A common challenge in multimedia data understanding is the unsupervised discovery of recurring patterns, or motifs, in time series data. The discovery of motifs in uni-variate time series is a well studied problem and, while being a relatively new area of research, there are also several proposals for multi-variate motif discovery. Unfortunately, motif search among multiple variates is an expensive process, as the potential number of sub-spaces in which a pattern can occur increases exponentially with the number of variates. Consequently, many multi-variate motif search algorithms make simplifying assumptions, such as searching for motifs across all variates individually, assuming that the motifs are of the same length, or that they occur on a fixed subset of variates. In this paper, we are interested in addressing a relatively broad form of multi-variate motif detection, which seeks frequently occurring patterns (of possibly differing lengths) in sub-spaces of a multi-variate time series. In particular, we aim to leverage contextual information to help select contextually salient patterns and identify the most frequent patterns among all. Based on these goals, we first introduce the contextually salient multi-variate motif (CS-motif) discovery problem and then propose a salient multi-variate motif (SMM) algorithm that, unlike existing methods, is able to seek a broad range of patterns in multi-variate time series.
From Affect Theoretical Foundations to Computational Models of Intelligent Affective Agents
Authors: Alfonso Bexy , Taverner Joaquin , Vivancos Emilio , Botti Vicente
Published: November 2021

The links between emotions and rationality have been extensively studied and discussed. Several computational approaches have also been proposed to model these links. However, is it possible to build generic computational approaches and languages so that they can be “adapted” when a specific affective phenomenon is being modeled? Would these approaches be sufficiently and properly grounded? In this work, we want to provide the means for the development of these generic approaches and languages by making a horizontal analysis inspired by philosophical and psychological theories of the main affective phenomena that are traditionally studied. Unfortunately, not all the affective theories can be adapted to be used in computational models; therefore, it is necessary to perform an analysis of the most suitable theories. In this analysis, we identify and classify the main processes and concepts which can be used in a generic affective computational model, and we propose a theoretical framework that includes all these processes and concepts that a model of an affective agent with practical reasoning could use. Our generic theoretical framework supports incremental research whereby future proposals can improve previous ones. This framework also supports the evaluation of the coverage of current computational approaches according to the processes that are modeled and according to the integration of practical reasoning and affect-related issues. This framework is being used in the development of the GenIA3 architecture.
Superpixel-Based Singular Spectrum Analysis for Effective Spatial-Spectral Feature Extraction
Authors: Subudhi Subhashree , Patro  Ramnarayan , Biswal Pradyut Kumar , Dell’Acqua Fabio
Published: November 2021

In the processing of remotely sensed data, classification may be preceded by feature extraction, which helps in making the most informative parts of the data emerge. Effective feature extraction may boost the efficiency and accuracy of the following classification, and hence various methods have been proposed to perform it. Recently, Singular Spectrum Analysis (SSA) and its 2-D variation (2D-SSA) have emerged as popular, cutting-edge technologies for effective feature extraction in Hyperspectral Images (HSI). Using 2D-SSA, each band image of an HSI is initially decomposed into various components, and then the image is reconstructed using the most significant eigen-tuples relative to their eigen-values, which represent strong spatial features for the classification task. However, instead of performing reconstruction on the whole image, it may be more effective to apply reconstruction to object-specific spatial regions, which is the proposed objective of this research. As an HSI may cover a large area, multiple objects are generally present within a single scene. Hence, spatial information can be highlighted accurately by specializing the reconstruction based on the local context. The local context may be defined by the so-called superpixels, i.e., finite sets of pixels that constitute a homogeneous set. Each superpixel may undergo tailored reconstruction, with a process expected to perform better than non-spatially-adaptive approaches. In this paper, a Superpixel-based SSA (SP-SSA) method is proposed where the image is first segmented into multiple regions using a superpixel segmentation approach. Next, each segment is individually reconstructed using 2D-SSA. In doing so, the spatial contextual information is preserved, leading to better classifier performance. The performance of the reconstructed features is evaluated using an SVM classifier. Experiments on four popular benchmark datasets reveal that, in terms of the classification accuracy, the proposed approach overperforms the standard SSA technique and various common spatio-spectral classification methods.
Review of the Yb3+:ScBO3 Laser Crystal Growth, Characterization, and Laser Applications
Authors: Lu Dazhi , Li Xiaoheng , Yu Haohai , Zhang Huaijin , Wang Jiyang
Published: November 2021

Passive Q-switching is an effective approach for generating pulsed lasers, owing to its compact and additional modulation-free design. However, to compare favorably with active Q-switching and multi-stage amplification, the output energy needs to be enhanced for practical applications. Kramers Ytterbium ion (Yb3+)-doped borate crystals, with their excellent energy storage capacity, have been proven to be high-potential laser gain mediums for achieving pulsed lasers with moderate and high output energy using passive Q-switching technology. In this study, the growth, characterization, and laser generation of one Yb3+-doped borate crystal, the Yb3+:ScBO3 crystal, are systematically reviewed. The continuous-wave and passive Q-switching laser characteristics are presented in detail, and the self-pulsations derived from intrinsic ground-state reabsorption are also demonstrated. The specific characteristics and experiments confirm the potential of the Yb3+:ScBO3 crystal for future pulsed laser applications with moderate or even high energy output.
Time-Domain Sound Field Reproduction with Pressure and Particle Velocity Jointly Controlled
Authors: Hu Xuanqi , Wang Jiale , Zhang Wen , Zhang Lijun
Published: November 2021

Particle velocity has been introduced to improve the performance of spatial sound field reproduction systems with an irregular loudspeaker array setup. However, existing systems have only been developed in the frequency domain. In this work, we propose a time-domain sound field reproduction method with both sound pressure and particle velocity components jointly controlled. To solve the computational complexity problem associated with the multi-channel setup and the long-length filter design, we adopt the general eigenvalue decomposition-based approach and the conjugate gradient method. The performance of the proposed method is evaluated through numerical simulations with both a regular loudspeaker array layout and an irregular loudspeaker array layout in a room environment.
A Stable and High-Precision Downward Continuation Method of Magnetic Data
Authors: Zhou Zhiwen , Wang Jun , Meng Xiaohong , Fang Yuan
Published: November 2021

Downward continuation is an effective technique that can be used to transform the magnetic data measured on one surface to the data that would be measured on another arbitrary lower surface. However, it suffers from amplitude attenuation and is susceptible to noise, especially when the continuation distance is large. To solve these problems, we present a stable and high-precision downward continuation method combining the ideas of equivalent source technique, Tikhonov regularization, radial logarithmic power spectrum analysis, and constrained strategy. To implement this method, the observed data is used to construct the equivalent source in the study area, and the small amount of measured magnetic data at the lower surface (relative to the original observation surface) is employed to constrain the calculation procedure simultaneously. Then the magnetic data at the target surface can be obtained by using a forward calculation procedure instead of the risky downward continuation procedure. The proposed method is tested on both synthetic model data and real magnetic data collected in the South China sea. Various obtained results demonstrate that the method reported in this study has higher accuracy and better noise resistance than the traditional downward continuation methods.
Comparison of Initial pH Adjustment Prior to Thermophilic Anaerobic Digestion of Lime-Treated Corn Stover via Liquid Digestate or CO2
Authors: Xiao Lei , Yang Man , Hu Di , Mei Yuxia , Zhao Shumiao , Liang Yunxiang
Published: November 2021

Neutralization with liquid digestate and CO2 was compared herein to adjust the pH of lime-treated corn stover. The effects on the thermophilic (55 °C) anaerobic digestion were also analyzed. Liquid digestate neutralization (LDN) caused a decrease in pH from 10.5 to 7.5 in 60 h and accumulation of acetic/isobutyric acids. The CO2 neutralization (CN) under solid-state conditions reduced the pH from 10.5 to 8.5 in 30 min, which is faster than that of LDN and did not affect the subsequent anaerobic digestion. Biomethane production rate indicates that LDN contributed to the performance of anaerobic digestion, but this was not sufficient to compensate for the loss of total biomethane yield, resulting in a negative net profit (i.e., revenue from increased energy production minus reagent cost). For CN under solid-state conditions, the biomethane production was highest in both liquid- and solid-state anaerobic digestion, and also obtained a net profit of 98.74–100.89 RMB/tonne dry biomass. Therefore, the solid-state condition CN is a more efficient and economic method for adjusting initial pH of lime-treated corn stover.
A Simulator for Educating the Digital Technologies Skills in Industry. Part One. Dynamic Simulation of Technological Processes
Authors: Koteleva Natalia , Kuznetsov Valentin , Vasilyeva Natalia
Published: November 2021

Digital technology is being introduced into all areas of human activity. However, there are a number of challenges in implementing these technologies. These include the delayed return on investment, the lack of visibility for decision-makers and, most importantly, the lack of human capacity to develop and implement digital technologies. Therefore, creating a digital training simulator for the industry is an actual task. This paper focuses on the first step in creating a digital training simulator for the industry: developing a dynamic process model. The process chosen is flotation, as it is one of the most common mineral processing methods. The simulation was performed in AVEVA Dynamic Simulation software. The model is based on a determination of reaction rate constants, for which, experiments were conducted on a laboratory pneumomechanical flotation machine with a bottom drive. The resulting model was scaled up to industrial size and its dynamic properties were investigated. In addition, the basic scheme of a computer simulator was considered, and the testing of the communication channels of a dynamic model with systems, equipment and software for digitalizing was conducted. The developed model showed acceptable results for its intended purpose, namely, an exact match to the technological process in terms of time. This helps to account for inertia and a fast response on all tested communication channels, as well as being acceptable for the real-time simulation speed of the solver.
Integration of Micro-Structured Photovoltaic Cells into the Ultra-Light Wing Structure for Extended Range Unmanned Aerial Vehicles
Authors: Ionescu Octavian Narcis , Cernica Ileana , Manea Elena , Parvulescu Catalin , Istrate Alin , Ionescu Gabriela , Suchea Mirela Petruta
Published: November 2021

There have been large developments in the unmanned aerial vehicles (UAV) industry over the last decade. Although UAV development was mainly for military related use in the beginning and despite there being fear surrounding the release of this technology to the open market for quite a long time, nowadays, there are a variety of applications where UAVs are used extensively, such as in agriculture, infrastructure inspection and monitoring, mobile retranslation relays for communications, etc. One of the weaknesses of electrically propelled UAVs is flight autonomy; there is often a difficult trade-of between the weight of the payload, batteries, and surface to be surveyed that is necessary to determine. There have been many attempts to use photovoltaic cells to increase the flight time for UAVs; however, a reliable solution has not yet been developed. The present paper presents improvements that have been conducted to extend the autonomy of electrically derived UAVs: instead of gluing photovoltaic cells on the wings, the new approach embeds the solar cells into the wing structure as well as develops a new wing that is significantly lighter to compensate for the weight added by the photovoltaic cells. It was demonstrated that by using this approach, a 33% increase in the flight time can be achieved with only one modified wing in a prototype vehicle.
Model Test Study on Deformation Characteristics of a Fissured Expansive Soil Slope Subjected to Loading and Irrigation
Authors: Li Zhiqing , Kong Youxing , Fu Le , Zhou Yingxin , Qian Zhengfu , Hu Ruilin
Published: November 2021

Expansive soils are characterized by repeated swelling and shrinkage. They cause great damage to engineering projects because of their expansiveness, over-consolidation and propensity to crack. However, the impact of cracks on the stability of an expansive soil slope during loading and irrigation is not yet fully understood. This study aimed to investigate the relationship between slope state and crack development in fissured expansive soils. A series of physical model tests with different types of cracks were conducted, in which the fissured expansive soil slopes were subjected to different loadings (1.6, 3.2, 4.8, 6.4, 16 MPa), and irrigated at a flow rate of 25 mL/min. The VIC-2d software, which utilizes the digital image correlation principle, was used to quantitatively obtain the horizontal and vertical strain data of the slope model. The closure and opening of cracks, and the slope state after loading and irrigation were monitored by strain data analysis using VIC-2d software. The results indicate that the excessive overlying stress revives the existing cracks and produces sliding along the crack interface. The sliding surface of the fissured expansive soil slope became shallower due to the water infiltration. It was demonstrated that the middle and foot of the fissured expansive soil slope were the key positions for reinforcement from the perspective of the mutual transformation of tensile strain and compressive strain on the surface of the slope. It is of great importance to study the relationship between the crack strain state and deformation trend of a slope subjected to loading and infiltration to understand the progressive surface- or shallow-layer sliding mechanisms, and reinforce key areas of the slopes in areas containing moderately or strongly expansive soils with abundant cracks.