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high levels of arbuscular mycorrhizal fungus colonization on Medicago truncatula reduces plant suitability as a host for pea aphids (Acyrthosiphon pisum)

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Insect Science 2020年第1期27卷 99-112页

作者： Elisa Garzo Eric Rizzo Alberto Fereres S.Karen Gomez nstituto de Ciencias Agrarias-Consejo Superior de Investigaciones Cientificas(ICA-CSIC) MadridSpain school of Biological Sciences University of Northern ColoradoGreeleyColoradoUSA

This study sheds light on a poorly understood area in insect-plant-microbe interactions,focusing on aphid probing and feeding behavior on plants with varying levels of arbuscular mycorrhizal(AM)fungus root *** investigates a commonly occurring interaction of three species:pea aphid Acyrthosiphon pisum,barrel medic Medicago truncatula,and the AM fungus Rhizophagus irregularis,examining whether aphid-feeding behavior changes when insects feed on plants at different levels of AM fungus colonization(42% and 84% root length colonized).Aphid probing and feeding behavior was monitored throughout 8 h of recording using the electrical penetration graph(EPG)technique,also,foliar nutrient content and plant growth were ***,aphids took longer to reach their 1st sustained phloem ingestion on the 84% AM plants than on the 42% AM plants or on *** aphids showed phloem ingestion on the 84% AM plants relative to the 42% AM *** of the 84% AM plants had higher percent carbon(43.7%)relative to controls(40.5%),and the 84% AM plants had reduced percent nitrogen(5.3%)relative to the 42% AM plants(6%).In conclusion,EPG and foliar nutrient data support the hypothesis that modifications in plant anatomy(e.g.,thicker leaves),and poor food quality(reduced nitrogen)in the 84% AM plants contribute to reduced aphid success in locating phloem and ultimately to differences in phloem sap *** work suggests that *** plants benefit from AM symbiosis not only because of increased nutrient uptake but also because of reduced susceptibility to aphids.

关键词： Aphididae arbuscular mycorrhizal fungus electrical penetration graph(EPG) Fabaceae Glomeraceae insect-plant-microbe interactions symbiosis

Ontogenetic shift in response to prey-derived chemical cues in prairie rattlesnakes Crotalus viridis viridis

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Current Zoology 2012年第4期58卷 549-555页

作者： Anthony J. SAVIOLA David CHISZAR Stephen E MACKESSY school of Biological Sciences University of Northern Colorado 501 20th Street CB 92 Greeley CO 80639 USA Department of Psychology CB 345 University of Colorado Boulder Colorado 80309 USA

Snakes often have specialized diets that undergo a shift from one prey type to another depending on the life stage of the snake. Crotalus viridis viridis （prairie rattlesnake） takes different prey at different life stages, and neonates typically prey on ectotherms, while adults feed almost entirely on small endotherms. We hypothesized that elevated rates of tongue flicking to chemical stimuli should correlate with particular prey consumed, and that this response shifts from one prey type to another as in- dividuals age. To examine if an ontogenetic shift in response to chemical cues occurred, we recorded the rate of tongue flicking for 25 neonate, 20 subadult, and 20 adult （average SVL = 280.9, 552, 789.5 mm, respectively） wild-caught C. v. viridis to chemi- cal stimuli presented on a cotton-tipped applicator; water-soluble cues from two ectotherms （prairie lizard, Sceloporus undulatus, and house gecko, Hemidactylusfrenatus）, two endotherms （deer mouse, Peromyscus maniculatus and lab mouse, Mus musculus）, and water controls were used. Neonates tongue flicked significantly more to chemical cues of their common prey, S. undulatus, than to all other chemical cues; however, the response to this lizard＇s chemical cues decreased in adult rattlesnakes. Subadults tongue flicked with a higher rate of tongue flicking to both S. undulatus and P. maniculatus than to all other treatments, and adults tongue flicked significantly more to P. maniculatus than to all other chemical cues. In addition, all three sub-classes demonstrated a greater response for natural prey chemical cues over chemical stimuli of prey not encountered in the wild （M. musculus and H. frenatus）. This shift in chemosensory response correlated with the previously described ontogenetic shifts in C. v. viridis diet. Be-cause many vipers show a similar ontogenetic shift in diet and venom composition, we suggest that this shift in prey cue dis- crimination is likely a general phenomenon among viperid snakes.

关键词： Gape-limited predator Prey choice Trophic adaptation Vomeronasal chemoreception

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美国私立中小学教育情况介绍

外国中小学教育 2006年第8期 46-48页

作者：喻快美国纽约horace Mann school

我是一个在美国长大的中国学生，现在纽约市一所独立学校读11年级。2005年冬天，我随父母回上海探亲。我父亲的朋友向我提起中国的私立学校，这个话题引起了我的兴趣。我知道中国的公立学校教育质量很高，但中国的私立学校和公立学校有... 详细信息

我是一个在美国长大的中国学生，现在纽约市一所独立学校读11年级。2005年冬天，我随父母回上海探亲。我父亲的朋友向我提起中国的私立学校，这个话题引起了我的兴趣。我知道中国的公立学校教育质量很高，但中国的私立学校和公立学校有什么不同？同时我也想把我在美国私立学校的学习体会以及其他一些私立学校的情况介绍一下，仅供中国教育研究专家参考。

关键词：私立中小学教育情况美国中国学生私立学校公立学校教育质量学习体会教育研究纽约市

Development and Preliminary Validation of the Older Adult Service Usage Assessment

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Advances in Aging Research 2017年第4期6卷 61-72页

作者： Nancy J. Karlin school of Psychological Sciences University of Northern Colorado Greeley CO USA

This study provides information on the development and factor scaling, validity, and reliability of a newly developed community service utilization measure (Older Adult Service Usage Assessment-OASUA). Analyzes indicate the OASUA can be used to assess current perceived community service use and satisfaction, as well as providing an indication for future service use and potential service needs with older persons. Additional data collection sites should be identified and a broader sample obtained so as to confirm the psychometric properties of the instrument in conjunction with further development of the OASUA.

关键词： Older Adult Home and Community-Based Services Rural Aging

Chemosensory response in stunted prairie rattlesnakes Crotalus viridis viridis

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Current Zoology 2013年第2期59卷 175-179页

作者： Anthony J. SAVIOLA David CHISZAR Hobart M. SMITH Stephen EMACKESSY school of Biological Sciences University of Northern Colorado Greeley CO 80639 USA. Department of Psychology University of Colorado Boulder Colorado 80309 USA Department of Ecology and Evolutionary Biology University of Colorado Boulder CO 80309 USA

Rattlesnakes use chemical stimuli in ambush site selection and for relocation of envenomated prey through atrike-induced chemosensory searching. Shifts in responsiveness to prey chemicals have been documented in many snakes, and often correlate with prey commonly taken as snakes increase in age and size as well as geographical locations of the species. For instance, neonate rattlesnakes that prey primarily on ectotherms responded most strongly to chemical cues of commonly taken lizard prey, whereas adult rattlesnakes that prey primarily on small mammals responded significantly to chemical cues of com- monly taken rodents. In the current study, 11 Prairie Rattlesnakes Crotalus viridis viridis which were classified as large neonates based on measures of snout-vent length （SVL） and body mass, yet chronologically were at or near adulthood, were tested for their responsiveness to chemical extracts of natural and non-natural prey items. Although the snakes had eaten only neonate lab mice （Mus musculus）, they responded significantly more to chemical cues of natural prey items and particularly to chemical cues of prey normally taken by subadults （Peromyscus mice and Sceloporus lizard）. These results suggest that ontogenetic shifts in re- sponsiveness to natural prey chemical cues are innately programmed and are not based on body size or feeding experience in C. v. viridis. This does not imply, however, that growth and experience are without effects, especially with novel prey or rare prey that have experienced recent population expansion [Current Zoology 59 （2）： 175-179, 2013].

关键词： Chemical cues Chemoreception Crotalus viridis viridis Prey choice Vomeronasal

Improvement of Renewable Bioenergy Production in Microbial Fuel Cells with Saponin Supplementation

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Journal of Sustainable Bioenergy Systems 2021年第2期11卷 82-93页

作者： Skylar Choi Yongjin Park Immanuel H. Anaborne Jin Sik Song Ji Woo Han So Hyun Jeon Jaewoo Kim James Kim Jinkwon Lee Paul S. Chung horace greeley high school Chappaqua NY USA Deerfield Academy Deerfield MA USA Oakton high school Vienna VA USA school of Arts & Sciences University of Virginia Charlottesville VA USA school of Arts & Sciences Emory University Atlanta GA USA Bachelor of Science Villanova University Villanova PA USA College of Letters & Sciences University of California Los Angeles Los Angeles CA USA school of Arts & Sciences University of Michigan Ann Arbor MI USA Division of Biological Sciences Revelle College University of California San Diego CA USA Fuzbien Technology Institute Rockville MD USA

Microbial fuel cell (MFC) is one of renewable biofuel production technology that directly converts biomass to electricity. Cellulosic biomass is particularly attractive renewable resources for its low cost and abundance and neutral carbon balance. However, methanogenesis remains as a major factor limiting MFC performance. The current study reports that saponin addition at 0.05% w/v dose to anolyte in MFCs inhibited methanogenesis and improves power generation and cellulose fermentation. Mediator-less two chamber H-type MFCs were prepared using rumen fluid as anode inocula at 20% v/v of anolyte to convert finely ground pine tree (Avicel) at 2%, w/v to electricity. Saponin was added to the anode of MFC at 0.005% or 0.05% v/v dosage for treatment. MFC power and current across an external resistor were measured daily for 10d. On d10, collected gases from anode compartment were measured for total gas volume and analyzed for gas composition on gas chromatography. Supplementation of saponin to MFC at 0.005% did not have any effects on electricity generation or biogas production and composition. Saponin at 0.05% dose reduced 10% of methane prod

关键词： Microbial Fuel Cells Saponin Bioenergy

The Patient Requesting Amputation

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Open Journal of Medical Psychology 2013年第4期2卷 193-196页

作者： Thomas M. Dunn Ryan M. Moroze school of Medicine University of Colorado Aurora USA school of Psychological Sciences University of Northern Colorado Greeley USA

Although infrequent, there are patients who present themselves to surgeons and ask that a limb be amputated. Generally, such patients fall into one of three categories. The first is those suffering from “Body Integrity Identity Disorder” (BIID), a condition in which individuals feel that one of their limbs is foreign to the rest of their body, and must be removed. The second category is Apotemnophilia, a fetishized desire to become an amputee to enhance sexual gratification. Such drive for sexual gratification may lead to requests for amputation. Finally, the third category is delusional beliefs secondary to severe mental illness that may compel an individual to seek amputation, or even attempt self-amputation. We present a fourth type of patient: the Global War on Terrorism veteran with a severely injured arm demanding amputation to fit in with others who use prosthetic devices. In this instance, the cause of injury was a motor vehicle collision. We speculate that our case is not the only one and that a fourth category of patient demanding amputation is emerging. Further study is needed.

关键词： Amputation Decision Making Capacity Body Integrity Identity Disorder Apotemnophilia Somatoparaphrenia

Visualization of Exact Invariant Solutions Associated with Atmospheric Waves in a Thin Circular Layer

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Journal of Applied Mathematics and Physics 2021年第5期9卷 901-919页

作者： Ranis N. Ibragimov Lauren D. Mongrain Benjamin Stimmel Olga Trozkaya Guang Lin Sheng Zhang Vesselin Vatchev Daniel Stankiewicz Wenatchee Valley College Wenatchee WA USA Novosibirsk State University Novosibirsk Russia Purdue University West Lafayette IN USA University of Texas Rio Grande Edinburg TX USA horace Greely high school Chappaqua NY USA

The purpose of the research was to investigate the exact solutions of nonlinear shallow water equations associated with planetary equatorial waves corresponding to the Cauchy-Poisson free boundary problem describing the nonstationary motion of an incompressible perfect fluid propagating around a solid circle. We consider water waves for which the ratio of the depth of fluid above the circular bottom to the radius of the circle is small (shallow water).

关键词： Atmospheric Waves Shallow Water Theory Exact Solutions

Heterotrophic and Autotrophic Soil Respiration under Simulated Dormancy Conditions

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Open Journal of Forestry 2015年第3期5卷 274-286页

作者： Daniel Beverly Scott Franklin school of Biological Sciences University of Northern Colorado Greeley CO USA Botany Department University of Wyoming Laramie WY USA

Carbon cycling research has increased over the past 20 years, but less is known about the primary contributors to soil respiration (i.e. heterotrophic and autotrophic) under dormant conditions. It is understood that soil CO2 effluxes are significantly lower during the winter of temperate ecosystems and assumed microorganisms dominate efflux origination. We hypothesized that heterotrophic contributions would be greater than autotrophic under simulated dormancy conditions. To test this hypothesis, we designed an experiment with the following treatments: combined autotrophic heterotrophic respiration, heterotrophic respiration, autotrophic respiration, no respiration, autotrophic respiration in vermiculite, and no respiration in vermiculite. Engelmann spruce seedlings and soil substrates were placed in specially designed respiration chambers and soil CO2 efflux measurements were taken four times over the course of a month. Soil microbial densities and root volumes were measured for each chamber after day thirty-three. Seedling presence resulted in significantly higher soil CO2 efflux rates for all soil substrates. Autotrophic respiration treatments were not representative of solely autotrophic soil CO2 efflux due to soil microbial contamination of autoclaved soil substrates;however, the mean autotrophic contributions averaged less than 25% of the total soil CO2 efflux. Soil microorganism communities were likely the primary contributor to soil CO2 efflux in simulated dormant conditions, as treatments with the greatest proportions of microbial densities had the highest soil CO2 efflux rates. Although this study is not directly comparable to field dormant season soil CO2 effluxes of Engelmann spruce forest, as snowpack is not maintained throughout this experiment, relationships, and metrics from such small-scale ecosystem component processes may yield more accurate carbon budget models.

关键词： Dormant Autotrophic Respiration Heterotrophic Respiration Dormant Soil CO2 Efflux Soil Respiration Engelmann Spruce