Browsing by Author "Yang, Fan"
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- AIvian: Birdwatching Android AppMolin, Brendan; Suddala, Suchith; Khan, Rehan; Bokhari, Rayaan; Pereira, Conrad; Majumdar, Aritra; Yang, Fan (2022-12-04)Our mobile application, AIvian, is a user-friendly application which leverages AI and provides the tools to allow any bird watchers, especially novice and casual users, to recognize and learn about birds in North America. In addition to providing guidance and information to beginners, the social networking aspects of our application will also connect users from a wide range of skill levels to enhance the bird watching experience through community participation and crowdsourcing.
- Cache Valley Virus in Aedes japonicus japonicus Mosquitoes, Appalachian Region, United StatesYang, Fan; Chan, Kevin K.; Marek, Paul E.; Armstrong, Philip M.; Liu, Pengcheng; Bova, Jacob E.; Bernick, Joshua N.; McMillan, Benjamin E.; Weidlich, Benjamin G.; Paulson, Sally L. (2018-03)We detected Cache Valley virus in Aedes japonicus, a widely distributed invasive mosquito species, in an Appalachian forest in the United States. The forest contained abundant white-tailed deer, a major host of the mosquito and virus. Vector competence trials indicated that Ae. j. japonicus mosquitoes can transmit this virus in this region.
- Dynamics of La Crosse virus: Surveillance, Control and Effect on Vector BehaviorYang, Fan (Virginia Tech, 2017-01-31)La Crosse virus (LACV) encephalitis is the most common and important endemic mosquito-borne disease of children in the U.S. with an estimated 300,000 annual infections. The disease is maintained in a zoonotic cycle involving the eastern treehole mosquito, Aedes triseriatus and small woodland mammals such as chipmunks and squirrels. The objectives of this study were 1) to conduct surveillance of LACV and other mosquito-borne viruses; 2) to evaluate the effect of virus infection on mosquito host-seeking and neurotransmitter levels, and 3) to determine the effectiveness of barrier sprays to control infected mosquito vectors. Our surveillance study demonstrated the involvement of an invasive species, Aedes japonicus, in the transmission cycle of Cache Valley virus (CVV). CVV is a mosquito-borne virus that is closely related to LACV. Thus, surveillance is a critical step in public health, providing pathogen distribution and frequency data as well as identifying and incriminating new vectors. LACV infection did not affect the host-seeking behavior of Ae. triseriatus females. Using high performance liquid chromatography with electrochemical detection (HPLC-ED), the levels of serotonin and dopamine were measured in infected and uninfected mosquitoes. Serotonin is known to affect blood-feeding and dopamine affects host-seeking. Serotonin levels were significantly lower in LACV-infected mosquitoes but dopamine levels were unaffected by virus. A previous study found that LACV infection caused an alteration in mosquito blood-feeding in a way that could enhance virus transmission. This work showed that LACV infection can reduce the level of serotonin in the mosquito, promoting virus transmission through altered blood-feeding without impairing the vector's ability to locate a host. Standard CDC bottle assays were used to evaluate the efficacy of two pyrethroids and two essential oil sprays on LACV infected and uninfected mosquitoes. LACV-infected Ae. triseriatus females were more susceptible to both pyrethroids than uninfected ones. Infection status did not affect the susceptibility of Ae. albopictus to either pyrethroid. The essential oils were inconsistent in their effects. These results demonstrate that barrier sprays may be a viable part of a mosquito control program, not just to reduce the biting rate but to potentially reduce the virus-infected portion of the vector population.
- Effects of La Crosse virus infection on the host-seeking behavior and levels of two neurotransmitters in Aedes triseriatusYang, Fan; Chan, Kevin K.; Brewster, Carlyle C.; Paulson, Sally L. (2019-08-09)Background La Crosse virus (LACV) infection has been shown to manipulate the blood-feeding behaviors of its main vector, Aedes triseriatus. Here, we investigated the effects of virus infection on serotonin and dopamine and their potential roles in host-seeking. In mosquitoes, serotonin depletion has been shown to interfere with blood-feeding but not host-seeking. Dopamine depletion does not affect either blood-feeding or host-seeking; elevations of dopamine, however, has been shown to inhibit host-seeking. The purpose of this study was to determine the effects of LACV infection on the host-seeking behavior of and neurotransmitter levels in Ae. triseriatus. Methods Host-seeking behavior was evaluated using a uni-port olfactometer and a membrane feeder assay. Levels of serotonin and dopamine in infected and control mosquito heads were measured using HPLC-ED. Results Infection with LACV significantly inhibited the activation and attraction of Ae. triseriatus females to a host. A higher proportion of uninfected Ae. triseriatus females were activated by the presence of a host compared to infected mosquitoes and more uninfected mosquitoes were full responders (95.7%) compared to infected ones (91.1%). However, infection with LACV did not significantly affect the landing, probing, or blood-feeding rates of female mosquitoes. LACV-infected mosquitoes had lower serotonin levels than controls (104.5 vs 138.3 pg/head) while the dopamine levels were not affected by infection status (282.3 vs 237 pg/head). Conclusions Our work suggests that virus-induced reduction of serotonin is related to previously reported blood-feeding alterations in LACV-infected mosquitoes and could lead to enhanced transmission and increased vectorial capacity. In addition, some aspects of host-seeking were inhibited by virus infection.
- Imaginal Discs - A New Source of Chromosomes for Genome Mapping of the Yellow Fever Mosquito Aedes aegyptiSharakhova, Maria V.; Timoshevskiy, Vladimir A.; Yang, Fan; Demin, Sergei Iu.; Severson, David W.; Sharakhov, Igor V. (PLOS, 2011-10-01)Background: The mosquito Aedes aegypti is the primary global vector for dengue and yellow fever viruses. Sequencing of the Ae. aegypti genome has stimulated research in vector biology and insect genomics. However, the current genome assembly is highly fragmented with only ,31% of the genome being assigned to chromosomes. A lack of a reliable source of chromosomes for physical mapping has been a major impediment to improving the genome assembly of Ae. aegypti. Methodology/Principal Findings: In this study we demonstrate the utility of mitotic chromosomes from imaginal discs of 4th instar larva for cytogenetic studies of Ae. aegypti. High numbers of mitotic divisions on each slide preparation, large sizes, and reproducible banding patterns of the individual chromosomes simplify cytogenetic procedures. Based on the banding structure of the chromosomes, we have developed idiograms for each of the three Ae. aegypti chromosomes and placed 10 BAC clones and a 18S rDNA probe to precise chromosomal positions. Conclusion: The study identified imaginal discs of 4th instar larva as a superior source of mitotic chromosomes for Ae. aegypti. The proposed approach allows precise mapping of DNA probes to the chromosomal positions and can be utilized for obtaining a high-quality genome assembly of the yellow fever mosquito.
- A meta-analysis of 1,119 manipulative experiments on terrestrial carbon-cycling responses to global changeSong, Jian; Wan, Shiqiang; Piao, Shilong; Knapp, Alan K.; Classen, Aimee T.; Vicca, Sara; Ciais, Philippe; Hovenden, Mark J.; Leuzinger, Sebastian; Beier, Claus; Kardol, Paul; Xia, Jianyang; Liu, Qiang; Ru, Jingyi; Zhou, Zhenxing; Luo, Yiqi; Guo, Dali; Langley, J. Adam; Zscheischler, Jakob; Dukes, Jeffrey S.; Tang, Jianwu; Chen, Jiquan; Hofmockel, Kirsten S.; Kueppers, Lara M.; Rustad, Lindsey E.; Liu, Lingli; Smith, Melinda D.; Templer, Pamela H.; Thomas, R. Quinn; Norby, Richard J.; Phillips, Richard P.; Niu, Shuli; Fatichi, Simone; Wang, Yingping; Shao, Pengshuai; Han, Hongyan; Wang, Dandan; Lei, Lingjie; Wang, Jiali; Li, Xiaona; Zhang, Qian; Li, Xiaoming; Su, Fanglong; Liu, Bin; Yang, Fan; Ma, Gaigai; Li, Guoyong; Liu, Yanchun; Liu, Yinzhan; Yang, Zhongling; Zhang, Kesheng; Miao, Yuan; Hu, Mengjun; Yan, Chuang; Zhang, Ang; Zhong, Mingxing; Hui, Yan; Li, Ying; Zheng, Mengmei (2019-09)Direct quantification of terrestrial biosphere responses to global change is crucial for projections of future climate change in Earth system models. Here, we synthesized ecosystem carbon-cycling data from 1,119 experiments performed over the past four decades concerning changes in temperature, precipitation, CO2 and nitrogen across major terrestrial vegetation types of the world. Most experiments manipulated single rather than multiple global change drivers in temperate ecosystems of the USA, Europe and China. The magnitudes of warming and elevated CO2 treatments were consistent with the ranges of future projections, whereas those of precipitation changes and nitrogen inputs often exceeded the projected ranges. Increases in global change drivers consistently accelerated, but decreased precipitation slowed down carbon-cycle processes. Nonlinear (including synergistic and antagonistic) effects among global change drivers were rare. Belowground carbon allocation responded negatively to increased precipitation and nitrogen addition and positively to decreased precipitation and elevated CO2. The sensitivities of carbon variables to multiple global change drivers depended on the background climate and ecosystem condition, suggesting that Earth system models should be evaluated using site-specific conditions for best uses of this large dataset. Together, this synthesis underscores an urgent need to explore the interactions among multiple global change drivers in under-represented regions such as semi-arid ecosystems, forests in the tropics and subtropics, and Arctic tundra when forecasting future terrestrial carbon-climate feedback.
- One thousand plant transcriptomes and the phylogenomics of green plantsLeebens-Mack, James H.; Barker, Michael S.; Carpenter, Eric J.; Deyholos, Michael K.; Gitzendanner, Matthew A.; Graham, Sean W.; Grosse, Ivo; Li, Zheng; Melkonian, Michael; Mirarab, Siavash; Porsch, Martin; Quint, Marcel; Rensing, Stefan A.; Soltis, Douglas E.; Soltis, Pamela S.; Stevenson, Dennis W.; Ullrich, Kristian K.; Wickett, Norman J.; DeGironimo, Lisa; Edger, Patrick P.; Jordon-Thaden, Ingrid E.; Joya, Steve; Liu, Tao; Melkonian, Barbara; Miles, Nicholas W.; Pokorny, Lisa; Quigley, Charlotte; Thomas, Philip; Villarreal, Juan Carlos; Augustin, Megan M.; Barrett, Matthew D.; Baucom, Regina S.; Beerling, David J.; Benstein, Ruben Maximilian; Biffin, Ed; Brockington, Samuel F.; Burge, Dylan O.; Burris, Jason N.; Burris, Kellie P.; Burtet-Sarramegna, Valerie; Caicedo, Ana L.; Cannon, Steven B.; Cebi, Zehra; Chang, Ying; Chater, Caspar; Cheeseman, John M.; Chen, Tao; Clarke, Neil D.; Clayton, Harmony; Covshoff, Sarah; Crandall-Stotler, Barbara J.; Cross, Hugh; dePamphilis, Claude W.; Der, Joshua P.; Determann, Ron; Dickson, Rowan C.; Di Stilio, Veronica S.; Ellis, Shona; Fast, Eva; Feja, Nicole; Field, Katie J.; Filatov, Dmitry A.; Finnegan, Patrick M.; Floyd, Sandra K.; Fogliani, Bruno; Garcia, Nicolas; Gateble, Gildas; Godden, Grant T.; Goh, Falicia (Qi Yun); Greiner, Stephan; Harkess, Alex; Heaney, James Mike; Helliwell, Katherine E.; Heyduk, Karolina; Hibberd, Julian M.; Hodel, Richard G. J.; Hollingsworth, Peter M.; Johnson, Marc T. J.; Jost, Ricarda; Joyce, Blake; Kapralov, Maxim V.; Kazamia, Elena; Kellogg, Elizabeth A.; Koch, Marcus A.; Von Konrat, Matt; Konyves, Kalman; Kutchan, Toni M.; Lam, Vivienne; Larsson, Anders; Leitch, Andrew R.; Lentz, Roswitha; Li, Fay-Wei; Lowe, Andrew J.; Ludwig, Martha; Manos, Paul S.; Mavrodiev, Evgeny; McCormick, Melissa K.; McKain, Michael; McLellan, Tracy; McNeal, Joel R.; Miller, Richard E.; Nelson, Matthew N.; Peng, Yanhui; Ralph, Paula E.; Real, Daniel; Riggins, Chance W.; Ruhsam, Markus; Sage, Rowan F.; Sakai, Ann K.; Scascitella, Moira; Schilling, Edward E.; Schlosser, Eva-Marie; Sederoff, Heike; Servick, Stein; Sessa, Emily B.; Shaw, A. Jonathan; Shaw, Shane W.; Sigel, Erin M.; Skema, Cynthia; Smith, Alison G.; Smithson, Ann; Stewart, C. Neal, Jr.; Stinchcombe, John R.; Szovenyi, Peter; Tate, Jennifer A.; Tiebel, Helga; Trapnell, Dorset; Villegente, Matthieu; Wang, Chun-Neng; Weller, Stephen G.; Wenzel, Michael; Weststrand, Stina; Westwood, James H.; Whigham, Dennis F.; Wu, Shuangxiu; Wulff, Adrien S.; Yang, Yu; Zhu, Dan; Zhuang, Cuili; Zuidof, Jennifer; Chase, Mark W.; Pires, J. Chris; Rothfels, Carl J.; Yu, Jun; Chen, Cui; Chen, Li; Cheng, Shifeng; Li, Juanjuan; Li, Ran; Li, Xia; Lu, Haorong; Ou, Yanxiang; Sun, Xiao; Tan, Xuemei; Tang, Jingbo; Tian, Zhijian; Wang, Feng; Wang, Jun; Wei, Xiaofeng; Xu, Xun; Yan, Zhixiang; Yang, Fan; Zhong, Xiaoni; Zhou, Feiyu; Zhu, Ying; Zhang, Yong; Ayyampalayam, Saravanaraj; Barkman, Todd J.; Nam-Phuong Nguyen; Matasci, Naim; Nelson, David R.; Sayyari, Erfan; Wafula, Eric K.; Walls, Ramona L.; Warnow, Tandy; An, Hong; Arrigo, Nils; Baniaga, Anthony E.; Galuska, Sally; Jorgensen, Stacy A.; Kidder, Thomas I.; Kong, Hanghui; Lu-Irving, Patricia; Marx, Hannah E.; Qi, Xinshuai; Reardon, Chris R.; Sutherland, Brittany L.; Tiley, George P.; Welles, Shana R.; Yu, Rongpei; Zhan, Shing; Gramzow, Lydia; Theissen, Gunter; Wong, Gane Ka-Shu (2019-10-31)Green plants (Viridiplantae) include around 450,000-500,000 species(1,2) of great diversity and have important roles in terrestrial and aquatic ecosystems. Here, as part of the One Thousand Plant Transcriptomes Initiative, we sequenced the vegetative transcriptomes of 1,124 species that span the diversity of plants in a broad sense (Archaeplastida), including green plants (Viridiplantae), glaucophytes (Glaucophyta) and red algae (Rhodophyta). Our analysis provides a robust phylogenomic framework for examining the evolution of green plants. Most inferred species relationships are well supported across multiple species tree and supermatrix analyses, but discordance among plastid and nuclear gene trees at a few important nodes highlights the complexity of plant genome evolution, including polyploidy, periods of rapid speciation, and extinction. Incomplete sorting of ancestral variation, polyploidization and massive expansions of gene families punctuate the evolutionary history of green plants. Notably, we find that large expansions of gene families preceded the origins of green plants, land plants and vascular plants, whereas whole-genome duplications are inferred to have occurred repeatedly throughout the evolution of flowering plants and ferns. The increasing availability of high-quality plant genome sequences and advances in functional genomics are enabling research on genome evolution across the green tree of life.
- Optimization of Cytogenetic and Physical mapping of Culicinae genomesYang, Fan (Virginia Tech, 2010-12-07)Understanding chromosome structure and genome organization of Culicine mosquitoes can potentially contribute to the development of novel approaches to vector control. However, because of highly repetitive nature of the Aedes and Culex genomes, the structure of their polytene chromosomes is damaged by ectopic contacts that make the analysis difficult. Mitotic chromosomes from imaginal discs of 4th instar larvae of Aedes aegypti were tested as a source for the physical genome mapping for this mosquito. Chromosomes in imaginal discs are 10 times more abundant than chromosomes in nervous ganglia, and they do not accumulate chromosomal mutation as cell line chromosomes do. Prometaphase chromosomes in imaginal discs of Ae. aegypti are 4-5 times longer than metaphase chromosomes and can provide higher resolution for physical mapping. Cold temperature (+16°C) was proven to increase the number of the chromosomes. Hypotonic solution treatment of live larvae was proven to elongate chromosomes and improve banding patterns. We differentially stained these mitotic chromosomes with Giemsa and YOYO-1 to revile the banding pattern. We applied fluorescent in situ hybridization (FISH) procedure developed for human chromosomes to Ae. aegypti chromosomes. A strain from Culex pipiens, Cx. quinquefasciatus and their hybrids from the natural population in Virginia was successfully colonized in the laboratory. This strain can be used as a reliable source for cytogenetic studies.
- Reluctant to Share: How Third Person Perceptions of Fake News Discourage News Readers From Sharing “Real News” on Social MediaYang, Fan; Horning, Michael A. (Sage, 2020)Rampant fake news on social media has drawn significant attention. Yet, much remains unknown as to how such imbalanced evaluations of self versus others could shape social media users’ perceptions and their subsequent attitudes and behavioral intentions regarding social media news. An online survey (N = 335) was conducted to examine the third person effect (TPE) in fake news on social media and suggested that users perceived a greater influence of fake news on others than on themselves. However, although users evaluated fake news as socially undesirable, they were still unsupportive of government censorship as a remedy. In addition, the perceived prevalence of fake news leads audiences to reported significantly less willingness to share all news on social media either online or offline.