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1.
Richard R. Budnik Joseph D. Conroy Richard D. Zweifel Stuart A. Ludsin Elizabeth A. Marschall 《Ecology of Freshwater Fish》2021,30(1):31-47
Rising temperatures caused by climate change are likely to affect cool‐water and warm‐water fishes differently. Yet, forecasts of anticipated temperature effects on fishes of different thermal guilds are lacking, especially in freshwater ecosystems. Towards this end, we used spatially explicit, growth rate potential (GRP) models to project changes in seasonal habitat quality for a warm‐water piscivore (largemouth bass Micropterus salmoides), a cool‐water piscivore (walleye Sander vitreus) and a hybrid piscivore (saugeye S. vitreus × S. canadensis) in two Midwestern reservoirs. We assessed habitat quality for two periods (early and middle 21st century) under two realistic greenhouse gas emission scenarios (a mid‐century emissions peak and a rapid continuous increase in emissions). Largemouth bass were projected to experience enhanced or slightly reduced habitat during all seasons, and throughout the mid‐21st century. By contrast, walleye habitat was projected to decline with anticipated warming, except during the spring in the smaller of our two study reservoirs and during the fall in the larger of our two study reservoirs. Saugeye habitat was projected to either increase modestly or decline slightly during the spring and fall and declines in habitat quality and quantity that were smaller than those for walleye were identified during summer. Collectively, our findings indicate that climate warming will differentially alter habitat suitability for reservoir piscivores, favouring warm‐water species over cool‐water species. We expect these changes in habitat quality to impact the dynamics of reservoir fish populations to varying degrees necessitating the consideration of climate when making future management decisions. 相似文献
2.
Maureen A. Griffin Ingrid M. Balsa Philipp D. Mayhew 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):572
A 7-month-old, intact male, mixed breed dog with bilateral inguinal hernias underwent general anesthesia for laparoscopic bilateral inguinal herniorrhaphy via a 3-port approach. A 3-dimensional laparoscopic system was used to perform the procedure immediately following prescrotal open castration. Intracorporeal suturing with polypropylene was performed, and 2 cruciate sutures were placed to close each inguinal ring. The caudal aspect of each inguinal ring was left slightly open so as not to disrupt the passage or patency of vessels and nerves. No intra- or post-operative complications occurred. One year after surgery, the dog has no evidence of recurrence of the inguinal hernias.Key clinical message:This case report demonstrates a novel minimally invasive approach to inguinal herniorrhaphy in a dog with no reported complications and a good long-term outcome. Intracorporeally sutured inguinal herniorrhaphy is feasible in dogs with good results, although additional cases are needed to gain experience with this technique in dogs with varying presentations of inguinal hernias. 相似文献
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Aedes albopictus (Skuse) is a globally significant vector that complexifies management programs already contending with Aedes aegypti (L.). The Ae. albopictus mosquito is a daytime biting, container breeding, anthropophilic mosquito that is generally considered unresponsive to operational larviciding that does not also incorporate source reduction. S-methoprene is a readily available juvenile hormone mimic common to pest management. This 14-week study examines direct and indirect treatment efficacy using s-methoprene as an ultra-low volume (ULV) truck spray in area-wide operations against Ae. albopictus in the southeastern United States. An overall 63.3% reduction of Ae. albopictus adults and 47.8% reduction of deposited eggs in treatment areas were observed compared with control. Indirect plots saw reduction in Ae. albopictus adults by 32.7% and eggs by 32.3%. Using insect growth regulator bioassays, truck-mounted ULV application of s-methoprene was effective to an inhibition of emergence (IE) of ≥92% within directly treated (sprayed) areas and >65% IE among containers placed up to 90 m away. S-methoprene could still benefit urban vector management programs when applied at an operational scale. 相似文献
8.
Mohd Shahanbaj Khan Manish K. Pandey S. Hemalatha 《Journal of Crop Science and Biotechnology》2018,21(5):459-467
Plants are sessile organisms that experience various abiotic stresses during their lifespan and try to adapt to these environmental stresses by manipulating their physiological, biochemical, cellular, and molecular mechanisms. Salinity is one of the important abiotic stress that affects the metabolism and physiology of plant cells that leads to serious damage to crops and productivity. We investigated the response of two contrasting (salt susceptible and tolerant) cultivars during saline stress by modulating its effect with the application of an important natural biostimulant panchagavya (PG). The results showed that the salinity stress greatly influenced and negatively affects the plant growth, biochemical attributes, and induces the expression of various genes in both cultivars. Furthermore, we assessed the effect of PG alone and by amending with NaCl to alleviate the saline stress which showed a significant enhancement of biochemical and physiological characteristics in both cultivars. Furthermore, we assessed the response of seven autophagy associated gene (ATG1, ATG3, ATG4, ATG6, ATG7, ATG8, and ATG9), BAX Inhibitor -1 (BI-1), Mitogen activated Protein Kinase–1 (MAPK-1), WRKY53, Catalase -1 (CAT-1), Superoxide Dismutase (SOD), and Glutathione Peroxidase (GPX) genes in rice that displayed the differential expression pattern during saline stress in both cultivars. We concluded that saline stress can be manipulated by the application of PG and positively regulate the physiological, biochemical, and gene expression response in salt-susceptible and -tolerant rice cultivars. Furthermore, the current study also suggested that salinity is a mutifactorial and multigenic response. Autophagy and programmed cell death regulated along with salinity and was helpful in adapting the tolerance against the stress condition. 相似文献
9.
Characterization of field‐evolved resistance to Bacillus thuringiensis‐derived Cry1F δ‐endotoxin in Spodoptera frugiperda populations from Argentina 下载免费PDF全文
Desmi I Chandrasena Ana M Signorini Gustavo Abratti Nicholas P Storer Magdalena L Olaciregui Analiza P Alves Clinton D Pilcher 《Pest management science》2018,74(3):746-754
BACKGROUND
Transgenic maize (Zea mays L.) event TC1507 (Herculex® I insect protection), expressing Cry1F δ‐endotoxin derived from Bacillus thuringiensis var. aizawai, was commercialized in 2003 in the Americas. Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) susceptibility to Cry1F was monitored annually across several regions in Argentina using diagnostic concentration bioassays. Reduced performance of TC1507 maize against S. frugiperda was reported in 2013. A resistant population was established in the laboratory and the dominance of Cry1F resistance was characterized.RESULTS
During 2012–2015, high‐survivorship of several populations was observed in the resistance monitoring program. Reciprocal crosses of a Cry1F‐resistant population with a Cry1F‐susceptible population were evaluated to calculate effective dominance (DML) based on mortality levels observed at 100 µg/ml Cry1F. Two additional dominance levels (DLC and DEC) were calculated using lethal (LC50) or effective concentration (EC50) derived from concentration–response bioassays. Estimates indicated that Cry1F resistance in S. frugiperda in Argentina was either highly recessive (DML = 0.005) or incompletely recessive (DLC < 0.26 and DEC < 0.19).CONCLUSION
This study is the first documented confirmation and characterization of S. frugiperda Cry1F field‐evolved resistance in Argentina. The resistance to Cry1F in S. frugiperda populations collected in Argentina, is autosomal and incompletely recessive similar to the resistance reported in Brazil. © 2017 The Authors. Pest Management Science published by John Wiley © Sons Ltd on behalf of Society of Chemical Industry. 相似文献10.
A. I. Fokina E. V. Dabakh L. I. Domracheva S. G. Skugoreva E. I. Lyalina T. Ya. Ashikhmina Yu. N. Zykova K. A. Leonova 《Eurasian Soil Science》2018,51(5):550-560
The comprehensive diagnostics of the state of soils in the impact zone of thermal power station (TPS-5) in the city of Kirov was performed on the basis of the soil chemical analyses and the study of biota response to the loads at different organization levels. The chemical analyses attested to a satisfactory state of the soils. However, the use of soil cyanobacteria and bird’s-foot trefoil (Lótus corniculátus) as test objects showed the toxicity of studied soil samples. The toxicity of the samples was judged from the bioindication effects of cyanophytization and melanization of soil microbial complexes. The obtained results demonstrated that at relatively low concentrations of total and mobile heavy metal compounds in the soil samples, their amount released into the tested soil water (1: 4) extract exceeded the limit allowable for normal functioning of living organisms. For the first time, the express cyanobacterial tetrazole-topographic method of biotesting was applied in the geoecological study to estimate the toxicity of the soil samples. The results obtained with the help of traditional and express methods proved to be comparable. The express-method was sufficiently sensitive and efficient. It allowed the determination of the samples' toxicity in five hours, i.e., four to five times faster than the traditional technique. An inverse relationship between the number of viable cells of cyanobacteria (as judged from the inclusion of formazan crystals) and the concentration of lead ions in the tested soil extracts was found. This finding can be considered a prerequisite for further study and application of the express method in the practice of geoecological monitoring. Our study demonstrated the necessity of a comprehensive approach for the assessment of the real ecological state of soils in the investigated impact zone of the thermal power station. 相似文献