{"title":"Cash crop or food crop? socioeconomic and geopolitical factors affecting smallholder farmer crop selection in times of crisis in southwestern Tajikistan","authors":"Aksana Zakirova, Henryk Alff, Matthias Schmidt","doi":"10.3389/fagro.2023.1228165","DOIUrl":"https://doi.org/10.3389/fagro.2023.1228165","url":null,"abstract":"Tajikistan's agricultural sector, primarily dominated by cotton cultivation, has experienced significant changes since the Soviet era. Although farmers introduced food crops into agricultural production to ensure food security after the collapse of the Soviet Union in 1991, the government still mandates that cotton cultivation occupy a considerable portion of Tajikistan's limited irrigated land. However, following the recent Covid-19 pandemic crisis, farmers have encountered the need to reassess their agricultural practices, given constrained governmental assistance and a range of socioeconomic considerations. This research adopts resilience as a conceptual framework to examine the coping strategies of smallholder farmers in the Khatlon region of Tajikistan, with a specific emphasis on the period spanning from 2019 to 2022. At the outset, our research employed the snowballing technique to increase respondent participation, later transitioning to a representative sample size that facilitated the collection of qualitative data from around 100 semi-structured interviews, 10 focus groups, and personal visits to agricultural fields over the course of four years. The paper not only demonstrates the overall creativity of Tajikistani farmers in growing and selecting non-cotton crops in this most recent period of crisis, but also points to wealthier farmers’ generally greater willingness to adopt technological innovations and gain new knowledge to apply to them. Although these strategies have been taken in order to address farmers’ immediate needs in troubled times against the backdrop of the existing state cotton policy, their sustainability remains uncertain. While the qualitative focus of this study bears certain inherent limitations, the data collected nevertheless show that this period of crisis has been generative for many farmers as they seek out new methods of subsistence.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135616769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lori Croghan, Alan G. Smith, Matthew A. Tancos, Neil O. Anderson, Roger L. Becker
{"title":"Benefits and risks of gene drives for invasive plant management - the case for common tansy","authors":"Lori Croghan, Alan G. Smith, Matthew A. Tancos, Neil O. Anderson, Roger L. Becker","doi":"10.3389/fagro.2023.1290781","DOIUrl":"https://doi.org/10.3389/fagro.2023.1290781","url":null,"abstract":"Invasive plants cause significant environmental and economic damage, but land managers have few control options. Common tansy ( Tanacetum vulgare ) is prevalent in many US states and is one of the most reported invasive plants in Minnesota. Controlling common tansy poses a challenge due to its extensive distribution and association with diverse plant communities. A gene drive is being explored as a genetic biocontrol method for the management of several non-native invasives, including common tansy in North America. Gene drives have emerged as a novel biotechnology application with potential to improve public health, promote conservation, and increase agricultural productivity. In common tansy, gene drives could be developed to target genes that would reduce or eliminate female fertility and consequently inhibit common tansy seed production. Using common tansy as an example, we outline risks associated with the use of gene drive technology for invasive plant control and explain how risks may be mitigated. Understanding potential benefits and risks associated with gene drives in the early stages of development is crucial. Mitigating risks, receiving stakeholder input, and navigating the regulatory environment will play an important role in gene drive development and deployment.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135569516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Yield stability of silage maize double cropping systems across nine German environments","authors":"Fruzsina Schmidt, Herwart Böhm, Hans-Peter Piepho, Peer Urbatzka, Michael Wachendorf, Rüdiger Graß","doi":"10.3389/fagro.2023.1235034","DOIUrl":"https://doi.org/10.3389/fagro.2023.1235034","url":null,"abstract":"Introduction Yield and its stability are both vital characteristics to evaluate the viability of cropping systems. However, the current frames of field research hardly allow an accurate evaluation of short-term effect stability. Therefore, over nine German environments (three years and three locations), first crop, maize, total harvested dry biomass yield (DMY), and maize dry matter content (DMC) variability were evaluated through a risk assessment in an organically managed silage maize experiment comprising 18 cropping systems. Material and methods The treatment factors included first crop group (pure legume, legume–cereal mixture), first crop (winter pea, hairy vetch and their mixtures with rye, control), management —incorporating first crop use and tillage (double cropping system no-till, double cropping system reduced till, double-cropped, mulched system terminated with roller-crimper, control), fertilization and mechanical weed control (yes–no), and row width (75 cm, 50 cm). Results and discussion The first crop DMY and maize DMC had a positive relationship with its variance, whereas maize DMY and total DMY had a negative relationship. The differences in risks were governed by system (number of crops), management and first crop ( group ), and followed compatible patterns with what was observed for their influence on the mean of the parameters. The pedological and climatic conditions, especially near maize sowing and establishment, and therefore the length of season are crucial in double cropping and double-cropped, mulched systems. In its current state, the location in the northern region of Germany was not well suited for the studied alternative systems, whereas in the other regions (central and south), double cropping systems with reduced tillage as well as double-cropped systems with pure legume mulches may offer alternative management systems for silage maize. Further optimization of the critical sowing and establishment phase may result in more diversified options for double cropping and double-cropped, mulched systems in the future.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135729738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
David Johnston-Monje, Laura Isabella Vergara, Jessica Lopez-Mejia, James Francis White
{"title":"Plant microbiomes as contributors to agricultural terroir","authors":"David Johnston-Monje, Laura Isabella Vergara, Jessica Lopez-Mejia, James Francis White","doi":"10.3389/fagro.2023.1216520","DOIUrl":"https://doi.org/10.3389/fagro.2023.1216520","url":null,"abstract":"Agricultural products such as tea, chocolate, coffee and wine are valued for their sensorial and nutritional qualities. Variation in the growing conditions of a crop can influence the plant’s phenotype, thus it behooves agriculturalists to optimize the conditions on their farms to grow the highest quality product. The set of growing conditions associated with a certain geographic location and its influence on the product’s chemistry is known as terroir. Although terroir plays a significant role in marketing and consumer appreciation as well as product identity and valorization, rarely are the biochemical differences or the factors creating them very well understood. The word derives from the Latin for “land”, suggesting terroir is simply a function of the geographical location where a plant grew, while in its modern usage, terroir is understood to be the result of soil type, climate, landscape, topography, biotic interactions and agricultural practice. Except for fermented food products like wine and chocolate, plant associated microbiomes have been little studied for their contribution to a crop’s terroir; however, modern metagenomics and metabolomics technologies have given scientists the tools to better observe how microbial diversity can impact the chemical variation in plant products. Differences in the microbiomes inhabiting plant organs can change phytochemistry by altering host metabolism, for example increasing the nutrients absorbed by roots that then are deposited in leaves, seeds and fruits. Plant associated microbes can consume plant molecules, removing them from the metabolome, or they can contribute smells and flavors of their own. This review aims to synthesize research into rhizosphere, endosphere, phyllosphere, spermosphere, carposphere, and anthosphere microbiome influences on plant biochemistry and crop derived products, while helping to increase the appreciation that beneficial microbes are able to contribute to agriculture by improving phytochemical quality.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135730872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jose A. Jimenez-Berni, Arantxa Cabello-Leblic, Alicia Lopez-Guerrero, Francisco J. Villalobos, Luca Testi, Elias Fereres
{"title":"Energy balance determination of crop evapotranspiration using a wireless sensor network","authors":"Jose A. Jimenez-Berni, Arantxa Cabello-Leblic, Alicia Lopez-Guerrero, Francisco J. Villalobos, Luca Testi, Elias Fereres","doi":"10.3389/fagro.2023.1244633","DOIUrl":"https://doi.org/10.3389/fagro.2023.1244633","url":null,"abstract":"Determining crop evapotranspiration (ET) is essential for managing water at various scales, from regional water accounting to farm irrigation. Quantification of ET may be carried out by several procedures, being eddy covariance and energy balance the most established methods among the research community. One major limitation is the high cost of the sensors included in the eddy covariance or energy balance systems. We report here the development of a simpler device (CORDOVA-ET: COnductance Recording Device for Observation and VAlidation of ET) to determine crop ET based on industrial-grade, commercial off-the-shelf (COTS) sensors costing far less than research-grade sensors. The CORDOVA-ET contains a sensor package that integrates the basic micrometeorological instrumentation and the infrared temperature sensors required for estimating ET over crops using the energy balance approach. One novel feature is the presence of four different nodes that allow the determination of ET in four different locations within a field or in four different fields of the same crop, thus allowing an assessment of ET spatial variability. The system was conceived as an open-source and hardware alternative to commercial devices, using a collaborative approach for the development of a regional ET network in countries of North Africa and the Near East. Comparisons of radiation, temperature, humidity, and wind against those of research-grade sensors yielded excellent results, with coefficients of correlation ( R 2 ) above 0.96. The estimated reference ET calculated from these measurements showed R 2 = 0.99 and a root mean square error (RMSE) of 0.22 mm/day. The infrared temperature measurements at the four different nodes showed an RMSE below 0.56°C. The energy balance components and estimates of ET from the CORDOVA-ET were validated against an eddy-covariance system over a wheat crop. The high ( R 2 ) for net radiation (0.98), sensible heat (0.88), and latent heat (0.86) showed good agreement between the modeled energy fluxes and the field measurements. The hardware components, acquisition, and data processing software are available as open-source repositories to facilitate adoption for different applications, from water use efficiency research to irrigation management.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136077858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nasib Koirala, David J. Barker, Russ W. Gesch, Yesuf Assen Mohammed, Nicholas J. Heller, Alexander W. Hard, Samantha S. Wells, Winthrop B. Phippen, Pamela Tas, Alexander J. Lindsey
{"title":"Seed treatment affected establishment and yield in two pennycress lines","authors":"Nasib Koirala, David J. Barker, Russ W. Gesch, Yesuf Assen Mohammed, Nicholas J. Heller, Alexander W. Hard, Samantha S. Wells, Winthrop B. Phippen, Pamela Tas, Alexander J. Lindsey","doi":"10.3389/fagro.2023.1205259","DOIUrl":"https://doi.org/10.3389/fagro.2023.1205259","url":null,"abstract":"Introduction Oilseed pennycress ( Thlaspi arvense L.) is an emerging biofuel crop for use in the aviation industry that has potential as a rotational crop in corn ( Zea mays L.)–soybean [ Glycine max (L.) Merr.] cropping sequences. Ensuring autumn emergence of pennycress after early broadcast seeding is key because this practice may result in uneven spatial distribution due to the small seed size and variable germination, soil contact, and moisture availability. The objective of this research was to evaluate the impact of five seed treatments and enhancements on autumn establishment in two pennycress lines (MN106NS and tt8-t/ARV1) in broadcast seeding compared with no treatment. Methods Tested treatments were (i) gibberellic acid (GA) soak, (ii) fludioxonil fungicide, (iii) pelleting with diatomaceous earth and a commercial binder, (iv) fungicide plus pelleting, or (v) fungicide plus pelleting with GA added to the binder. Seeds were planted at nine sites in four U.S. states to assess establishment (stand counts and percentage canopy cover) in the autumn and spring and seed yield after maturity. Results The MN106NS line had greater plants m −2 and percent green cover with treatments that included GA compared to the control. Line tt8-t/ARV1 had reduced stands when pelleted compared to the untreated, and establishment was unchanged when treated with GA compared to the untreated. Pelleting treatments without GA were not beneficial for stand establishment of either line. Seed yield for MN106NS was 20% greater than the untreated when treated with GA only or pelleted. Seed yield for tt8-t/ARV1 did not increase over the untreated with any treatment and was reduced by 20%–40% when pelleted. Discussion These results suggest minimal benefit of seed treatment and pelleting for the tested lines under broadcast seeding, though black-seeded lines may still benefit from GA treatment. Plant establishment and yield were negatively correlated with total precipitation post-planting, suggesting that excessive rainfall post-planting (>60 mm) may impede establishment when broadcast seeded.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136013508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"How farmers perceive perennial weeds in Northern France and Eastern Germany","authors":"Sabine Andert, Julie Guguin, Merle Hamacher, Muriel Valantin-Morison, Baerbel Gerowitt","doi":"10.3389/fagro.2023.1247277","DOIUrl":"https://doi.org/10.3389/fagro.2023.1247277","url":null,"abstract":"European farmers are required to follow the transition towards sustainable agriculture and food systems. Perennial weed management without chemical herbicides and inversion tillage is challenging farmers. Questions arise to cope with these spreading weeds. Our study focuses on farmers’ perceptions and experiences of perennial weeds and their control in Northern France and Eastern Germany. A survey was developed to explore the situation regarding present concerns and future problems for perennial weed control. The survey conducted from winter 2020/21 to spring 2021 targeted conventional, conservation and organic farms. We found a high level of awareness for perennial weeds. On average, 80.0% of Northern French farmers and 65.9% of Eastern German farmers revealed present concerns about perennial weeds. Both, Northern French and Eastern German farmers perceived perennial weeds are more damaging to crop production than other pests. In both regions, the farmers considered Cirsium arvense (L.) Scop. as the most important perennial weed. While the majority of the Eastern German farmers observed field infestations of Elymus repens (L.) Gould, Northern French farmers more often reported Sonchus arvensis L. infestations. More than 50% of the farmers stated Rumex spp. infestations in Northern France and Eastern Germany. Interestingly, Eastern German farmers are more concerned about future perennial weed problems than Northern French farmers. The reasons for farmer’s future concerns are probably connected to the farming system. In both regions, conservation and conventional farmers heavily rely on herbicides for perennial weed control, however, more farms used the active ingredient glyphosate in Eastern Germany. Nonetheless, perennial weed control is a major concern for organic farmers in both regions. We conclude that optimizing and integrating non-chemical alternatives is promising in all farming systems. Research activities are required to provide farmers and extension services with novel and profitable perennial weed management practices.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136209720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zachariah Degon, Seth Dixon, Yasir Rahmatallah, Mary Galloway, Sophia Gulutzo, Hunter Price, John Cook, Galina Glazko, Arijit Mukherjee
{"title":"Azospirillum brasilense improves rice growth under salt stress by regulating the expression of key genes involved in salt stress response, abscisic acid signaling, and nutrient transport, among others","authors":"Zachariah Degon, Seth Dixon, Yasir Rahmatallah, Mary Galloway, Sophia Gulutzo, Hunter Price, John Cook, Galina Glazko, Arijit Mukherjee","doi":"10.3389/fagro.2023.1216503","DOIUrl":"https://doi.org/10.3389/fagro.2023.1216503","url":null,"abstract":"Major food crops, such as rice and maize, display severe yield losses (30-50%) under salt stress. Furthermore, problems associated with soil salinity are anticipated to worsen due to climate change. Therefore, it is necessary to implement sustainable agricultural strategies, such as exploiting beneficial plant-microbe associations, for increased crop yields. Plants can develop associations with beneficial microbes, including arbuscular mycorrhiza and plant growth-promoting bacteria (PGPB). PGPB improve plant growth via multiple mechanisms, including protection against biotic and abiotic stresses. Azospirillum brasilense , one of the most studied PGPB, can mitigate salt stress in different crops. However, little is known about the molecular mechanisms by which A. brasilense mitigates salt stress. This study shows that total and root plant mass is improved in A. brasilense -inoculated rice plants compared to the uninoculated plants grown under high salt concentrations (100 mM and 200 mM NaCl). We observed this growth improvement at seven- and fourteen days post-treatment (dpt). Next, we used transcriptomic approaches and identified differentially expressed genes (DEGs) in rice roots when exposed to three treatments: 1) A. brasilense , 2) salt (200 mM NaCl), and 3) A. brasilense and salt (200 mM NaCl), at seven dpt. We identified 786 DEGs in the A. brasilense -treated plants, 4061 DEGs in the salt-stressed plants, and 1387 DEGs in the salt-stressed A. brasilense -treated plants. In the A. brasilense -treated plants, we identified DEGs involved in defense, hormone, and nutrient transport, among others. In the salt-stressed plants, we identified DEGs involved in abscisic acid and jasmonic acid signaling, antioxidant enzymes, sodium and potassium transport, and calcium signaling, among others. In the salt-stressed A. brasilense -treated plants, we identified some genes involved in salt stress response and tolerance (e.g., abscisic acid and jasmonic acid signaling, antioxidant enzymes, calcium signaling), and sodium and potassium transport differentially expressed, among others. We also identified some A. brasilense -specific plant DEGs, such as nitrate transporters and defense genes. Furthermore, our results suggest genes involved in auxin and ethylene signaling are likely to play an important role during these interactions. Overall, our transcriptomic data indicate that A. brasilense improves rice growth under salt stress by regulating the expression of key genes involved in defense and stress response, abscisic acid and jasmonic acid signaling, and ion and nutrient transport, among others. Our findings will provide essential insights into salt stress mitigation in rice by A. brasilense .","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135591001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Prediction of seasonal population dynamics of Grapholita molesta (Busck) and Adoxophyes orana (Fischer von Röslerstamm) in peach orchards using sex pheromone trap and degree-days and its implications in pest management","authors":"He Zhang, Aihong Ma, Hongfan Ran, Xiaofan Yang, Jianbo Hao, Jianfeng Zhang, Huijie Li, Zihang Yu, Xiaoxi Wang, Xiong Zhao He, Jiancheng Li","doi":"10.3389/fagro.2023.1269977","DOIUrl":"https://doi.org/10.3389/fagro.2023.1269977","url":null,"abstract":"The successful management of lepidopteran moths in orchards usually depends on the precise forecast of adult activity. However, the seasonal phenology of moths varies between crop cultivars and years, making it difficult to schedule the control measures. Here, we monitored male flight activity of oriental fruit moth Grapholita molesta and summer fruit tortrix moth Adoxophyes orana by using sex pheromone traps in peach orchards of three different cultivars for three successive years. We developed a logistic multiple-peaks model to fit data and then calculated degree-days (DD) required for male activity and neonate emergency. Results show that G. molesta and A. orana males had 4–5 and 3 flight peaks per year, respectively. The seasonal phenology of G. molesta or A. orana was quite stable with an identical timing of each flight peak between cultivars in a year. The flight activity was usually higher in the second and third peaks for both moths, with a higher cumulative number of G. molesta males captured than that of A. orana . Compared to A. orana , G. molesta emerged early in spring and required lower degree-days to reach the subsequent flight peaks and for neonate emergency. Our results suggest that to decline the possibility of outbreaks of moths during the growing seasons, pheromone traps should be scheduled in April with a cumulative DD between 49.6 and 207.1 for G. molesta and in mid-May–early June with a cumulative DD between 450.4 and 866.7 for A. orana , aiming to trap the newly emerged male adults or disrupting female mating success of overwintered moths in orchards. Based on the thermal requirement for egg hatching (i.e., 79.4 DD for G. molesta and 90.0 DD for A. orana ), insecticide treatments would be applied in late-April–early May and late May–early June to reduce the field population density of neonates of G. molesta and A. orana , respectively, to reduce fruit damage in orchards. Furthermore, pheromone traps set up in late July–early August (573.8–1025.2 DD) for G. molesta and in mid-September (1539.7–1788.9 DD) for A. orana may suppress overwintering populations and thus decrease pest infestation in next year.","PeriodicalId":34038,"journal":{"name":"Frontiers in Agronomy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135591341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}