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Lower marine productivity increases agonistic interactions between sea lions and fur seals in Northern Pacific Patagonia

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Current Zoology 2022年第6期68卷 657-666页

作者： Felipe MONTALVA hector PAVES Diego PEREZ-VENEgAS Karin g BARRIENTOS E Carola VALENCIA Diego MIRANDA-URBINA Mauricio SEgUEL Facultad de Ciencias Biologicas Pontificia Universidad Catolica de ChileSantiagoChile Departamento de Ciencias Basicas Facultad de CienciasUniversidad Santo TomasOsornoChile Centro de Investigacion y gestion de Recursos Naturales(CIgREN) Instituto de BiologıaFacultad de CienciasUniversidad de ValparaısoValparaısoChile Programa de Doctorado en Ciencias Agrarias Escuela de Graduados de laFacultad de Ciencias Agrarias y AlimentariasUniversidad Austral de ChileValdiviaChile Facultad de Medicina Veterinaria Sede PatagoniaUniversidad San SebastianPuerto MonttChile Instituto de Ciencias Biologicas Universidad de TalcaTalcaChile Department of Pathobiology Ontario Veterinary CollegeUniversity of GuelphGuelphCanada

Interspecific interactions are key drivers of individual and population-level fitness in a wide range of ***,in marine ecosystems,it is relatively unknown which biotic and abiotic factors impact behavioral interactions between competing *** assessed the impact of weather,marine productivity,and population structure on the behavioral agonistic interactions between South American fur seals(SAFSs),Arctocephalus australis,and South American sea lions(SASLs),Otaria byronia,in a breeding colony of *** hypothesized that agonistic interactions between SAFSs and SASLs respond to biotic and abiotic factors such as SAFS population structure,marine productivity,and *** found that SASL and SAFS interactions almost always resulted in negative impacts on the social structure or reproductive success of the SAFS *** adult males initiated stampedes of SAFS and/or abducted and predated SAFS *** SAFS males abundance and severe weather events were negatively correlated with agonistic interactions between ***,proxies for lower marine productivity such as higher sea surface temperature and lower catches of demerso-pelagic fish were the most important predictors of more frequent agonistic interactions between SAFS and *** the current scenario of decline in marine biomass due to global climate change and overfishing,agonistic interactions between competing marine predators could increase and exacerbate the negative impacts of environmental change in these species.

关键词： interspecific interactions climate change guafo Island sea surface temperature South American fur seal South American sea lion

In Vitro-Propagation of Agave tequilana Weber *** in a Temporary Immersion System

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 83-96页

作者： Otilio Vázquez-Martínez Héctor gordon Núñez-palenius Eugenio M.Pérez-Molphe Balch Mauricio Valencia-Posadas Luis Pérez-Moreno graciela M.L.Ruiz-Aguilar M.gómez-Lim División de Ciencias de la Vida Universidad de GuanajuatoIrapuato36500México Departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México Departamento de Ingeniería genética CINVESTAV Unidad IrapuatoIrapuato36500México

In Mexico,there is a need to produce large quantities of plantlets for the establishment and replanting of blue(***)agave production *** of these plots are within the origin denomination area(DOT,Spanish acronym)of the distilled product of this plant,known as *** objective of this study was to develop an in vitropropagation protocol for Agave tequilana Weber *** using segmented stems in both:solid and liquid media.A disinfection and in vitro technique were developed to obtain shoots,through plantlets collected in commercial plots,which attained 100%surface-disinfection and budding *** the multiplication stage,the effects of 6-Benzylaminopurine(BA)(0.0,4.4 and 13.2μM)and kinetin(0.0,9.4,18.8 and 37.6μM)were evaluated on lateralshoot production of segmented sagittal *** were cultivated on Murashige&Skoog(MS)medium,with the addition of 3.0%sucrose and 8 g L−1 *** was observed that BA and kinetin increased the number of shoots per explant,obtaining up to 18 and 26,***,it was found that just the sagittal segmentation of explants increased axillary *** the other hand,segmented-stem bases were grown in MS liquid medium with 3.0%sucrose,inside a RITAsystem,programmed by a 5 min immersion step with a frequency of every 4 *** effect of Indole−3-Acetic acid(IAA)(0.57,2.9,5.7μM)was evaluated,while maintaining a concentration of BA(13.2μM).It was observed that the greatest concentration of IAA led to the formation of more than 20 buds per *** results offer a new methodology to increase the efficiency of *** Weber ***-in vitro multiplication by sagittal segmentation of stems and the addition of BA and/or IAA.

关键词： Plant tissue culture stem-disk culture tequila in vitro culture

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富空穴CoSi合金无溶剂无碱醇氧化

Chinese Journal of Catalysis 2023年第5期48卷 175-184页

作者：赵志月蒋志伟黄一哲 Mebrouka Boubeche Valentina g.Matveeva hector F.garces 罗惠霞严凯中山大学环境科学与工程学院广东广州510006 中山大学材料与工程学院光电材料与技术国家重点实验室广东广州510006 特维尔国立技术大学生物技术与化学系俄罗斯布朗大学工程学院美国

醇类化合物选择性氧化为醛、酸和酯在工业应用中是一类重要的化学反应.按照绿色化学的要求,无溶剂、无外加碱源,以分子氧为氧化剂,对醇类氧化反应提出了重要挑战,特别是无溶剂氧化醇制备酯类化学品.因此开发高效催化剂应用于无溶剂醇氧... 详细信息

醇类化合物选择性氧化为醛、酸和酯在工业应用中是一类重要的化学反应.按照绿色化学的要求,无溶剂、无外加碱源,以分子氧为氧化剂,对醇类氧化反应提出了重要挑战,特别是无溶剂氧化醇制备酯类化学品.因此开发高效催化剂应用于无溶剂醇氧化成为研究热点.目前Pd基贵金属催化剂应用于醇的无溶剂氧化已取得一定进展,但贵金属的稀缺性限制了其工业应用.由于碱性环境可以有效促进醇的氧化,但碱性物质的添加可能导致反应体系的二次污染.此外,Co基非贵金属催化剂可以有效无溶剂氧化醇,但稳定性一般.因此,合成高活性高稳定性催化剂用于醇类化合物的无溶剂选择性氧化是重要的科学问题.本文采用电弧熔炼法可控制备半金属CoSi合金(AM-CoSi),在无溶剂无碱条件下将其应用于六种芳香醇的选择性氧化.采用X射线吸收精细结构谱、电子顺磁共振和球差扫描透射电镜对AM-CoSi催化剂进行结构表征,发现其以钴硅合金的形式存在,具有Co空穴和Si空穴,并且以Si空穴为主.反应结果表明,使用AM-CoSi催化剂在220℃可完全转化苯甲醇,并以70%的产率得到苯甲酸苄酯(BBE),使用无缺陷CoSi合金,只得到9.5%的BBE,说明Si空穴存在可以高效的转化苯甲醇并高产率得到BBE.此外,通过调控反应温度,使用AM-CoSi无溶剂氧化六种芳香醇(带有不同吸电子基团和供电子基团)可高选择性得到对应的醛,选择性高达84%以上.中间体反应实验结果表明,AM-CoSi催化剂具有很好的酯化催化活性,苯甲醇首先氧化成苯甲醛,再氧化成苯甲酸,然后苯甲酸与苯甲醇发生酯化反应生成BBE.采用单组分合金成分和无空穴CoSi合金(S-CoSi)进行催化剂对比实验,发现合金结构和空穴有利于苯甲醇的氧化.设计无空穴CoSi合金、Co空穴CoSi合金和Si空穴CoSi合金三种催化剂模型,并利用密度泛函理论计算模拟苯甲醇在这三种模型上的氧化路径,结果表明,CoSi合金结构促进醇的转化,Si空穴有利于BBE的产生.综上,本文将为其他半金属合金催化剂的合成和应用提供了新思路.

关键词：半金属合金醇氧化无溶剂空穴密度泛函理论计算

Agolin Ruminant^®, an Essential Oil Blend, Increases Energy-Corrected Milk and Feed Efficiency in a High Component Dairy Herd

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Open Journal of Animal Sciences 2023年第3期13卷 272-282页

作者： Jorge Noricumbo-Saenz Peter Williams hector garcia Feedworks USA Ltd. Cincinnati OH USA Moxee Dairy Moxee WA USA

Agolin® Ruminant (Agolin) is a blend of essential oils developed to improve feed efficiency while at the same time reducing rumen enteric methane production. Studies have shown that the product improves lactational performance, but the range of results has been varied. This experiment evaluated the effects of the feed additive Agolinon milk production in a high-component (fat and protein) dairy herd when provided for an extended time. The experiment was conducted at a large commercial dairy in the Pacific Northwest, USA. Eight pens of cows (350 to 500 cows/pen) were blocked by production, and pens within blocks were randomly assigned to treatment. All pens received a common total mixed ration. Treatment consisted of providing 1 g/cow/day of Agolin to the test group. A 4-week adaptation period was followed by an 11-week study period. Milk production and milk composition were determined by cow by averaging daily performance for the one-week period before the start of the trial (covariate period) and the last week of each of the two test periods. Feed intakes were determined by pen at the same time. Milk yield was 1.11 kg/cow/day greater (P g/cow/day greater (P g the feed additive. Similarly, protein yields were 0.03 (P g/cow/day greater (P g period. Milk fat yield was not different (P = 0.854) between treatment groups at the midpoint of the trial but increased with treatment (P = 0.002) by the end of the trial. Energy-corrected milk/feed ratio, based on pen parameters, was significantly altered by treatment at the final test period (1.48 vs. 1.64 kg/kg for control and test treatments, respectively).

关键词： greenhouse gas Mitigation Methane Feed Efficiency Lactating Dairy Cows Agolin

Using high-throughput data and dynamic flux balance modeling techniques to identify points of constraint in xylose utilization in Saccharomyces cerevisiae

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Systems Microbiology and Biomanufacturing 2021年第1期1卷 58-75页

作者： William Hohenschuh Ronald E.hector Frank Chaplen ganti S.Murthy Oregon State University CorvallisUSA USDA ARSNCAURPeoriaUSA Present Address:EMD Serono Inc. RocklandUSA Present Address:Indian Institute of Technology-Indore IndoreIndia

Background Several enzymes and cofactors have been identified as contributing to the slow utilization of xylose by xylose-fermenting strains of Saccharomyces ***,there has been no consensus on which of these possible bottle-necks are the most important to address.A previous strain characterization study from our lab suggested that insufficient NAD+limits fermentation and may be the most important bottleneck affecting utilization of xylose for the production of *** development and validation of a genome scale dynamic flux balance model would help to verify the existence and extent of this and other metabolic bottlenecks and suggest solutions to guide future strain development thereby minimiz-ing bottleneck impact on process *** A dynamic flux balance model was developed to identify bottlenecks in several strains of ***,both with wild-type pentose phosphate pathway expression and with the pathway over ***1 was found to be limiting in the oxidative portion of the pentose phosphate pathway under oxygen replete *** pathway is used to regenerate *** oxygen limiting conditions,respiration of xylose was limited by the lack of oxygen as a terminal electron *** production was also limited under these conditions due to the inability to balance NAD+/*** model suggests the use of the anaplerotic glyoxylate pathway to improve NAD+/NADH balance,increasing ethanol produc-tion by 50%while producing succinate as a coproduct at upwards of 20 g/*** In the production of high value chemicals from biomass,the use of the respiratory metabolism is a waste of feedstock *** previously identified in the oxidative pentose phosphate pathway are currently only relevant under oxygen-replete conditions and cannot impact the partitioning of carbon between the respiratory and fermentative *** future efforts on the non-respiratory balancing of NAD+/NADH,perhaps through th

关键词： Xylose Ethanol Biofuel Lignocellulose Metabolic bottlenecks Flux balance analysis Modeling Cofactor imbalance glyoxylate pathway NAD+ NADH

Development and characterization of Saccharomyces cerevisiae strains genetically modified to over-express the pentose phosphate pathway regulating transcription factor STB5 in the presence of xylose

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Systems Microbiology and Biomanufacturing 2021年第1期1卷 42-57页

作者： William Hohenschuh Ronald E.hector Jeffrey A.Mertens ganti S.Murthy Biological and Ecological Engineering Oregon State University116 Gilmore HallCorvallisOR 97331USA USDA ARSNCAURPeoriaIL 61604USA Present Address:EMD Serono Inc. RocklandMA 02370USA Present Address:Biosciences and Biomedical Engineering Indian Institute of Technology-IndorePOD 1A704 Khandwa RoadSimrolMadhya Pradesh 453552India

Background Several enzymes in the pentose phosphate pathway of Saccharomyces cerevisiae have been identified as relating to the constraint of xylose consumption and conversion to ***,no strategy has been proposed for simultaneous regulation of all contributing *** multiple enzymes contribute to constraint,over expression of a native transcription factor controlling the entire constraining pathway may provide optimal pathway wide *** characterization of this strain on both pure sugars and lignocellulosic hydrolysates would provide an opportunity to identify additional bot-tlenecks not addressed by the modification of the pentose phosphate pathway expression *** A series of strains were developed expressing STB5 and PgI1 under the control of a novel xylose inducible *** transcription of STB5 and its regulatory targets was verified via *** statistically significant difference was found in terms of xylose consumption or ethanol yield in these strains versus control *** consumption through both the fermentative and respiratory pathways appeared to be related to oxygen availability and culture density with high-density(low oxygen)cultures consuming xylose more slowly than low-density *** maximum specific consumption rate for high-density cultures was 0.21 g xylose/gDCW/h versus 0.41 g xylose/gDCW/h in lower density *** similar ethanol yields at high and low density(approximately 0.25 g ethanol/g xylose)suggest that the maximum rate of fermentation is linked to the rate of respiration in a stoichiometric *** This study did not find evidence supporting the pentose phosphate pathway constraint identified in other ***,NAD+availability mediated by oxygen availability and citric acid cycle flux was suggested to limit *** increased aeration could provide increased conversion of NAD+to NADH(and a stoichiometric increase in fermen-tatio

关键词： Xylose Ethanol Biofuel Lignocellulose Metabolic bottlenecks STB5 Xylose inducible NAD+/NADH Cofactor imbalance Saccharomyces cerevisiae

Scientific case studies in land-use driven soil erosion in the central United States: Why soil potential and risk concepts should be included in the principles of soil health

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International Soil and Water Conservation Research 2018年第1期6卷 63-78页

作者： Benjamin L.Turner Jay Fuhrer Melissa Wuellner hector M.Menendez Barry H.Dunn Roger gates Texas A&M University-Kingsville Department of AgricultureAgribusinessand Environmental Science700 University Blvd.MSC 228KingsvilleTX 78363USA North Dakota Natural Resource Conservation Service 220 East Rosser AvenuePO Box 1458BismarckND 58502-1458USA University of Nebraska-Kearney Department of BiologyBruner Hall of Science240111th AvenueKearneyNE 68849-1140USA South Dakota State University Department of Natural Resource ManagementBox 2140BBrookingsSD 57007USA South Dakota State University Box 2201BrookingsSD 57007USA University of georgia 104 S.Thornton Ave.DaltonGA 30720USA

Despite recent improvements in overall soil health gained through conservation agriculture, which has become a global priority in agricultural systems, soil and water-related externalities (e.g., wind and water erosion) continue to persist or worsen. Using an inductive, systems approach, we tested the hypothesis that such externalities persist due to expansion of cultivation onto areas unsuitable for sustained production. To test this hypothesis, a variety of data sources and analyses were used to uncover the land and water resource dynamics underlying noteworthy cases of soil erosion (either wind or water) and hydrological effects (e.g., flooding, shifting hydrographs) throughout the central United States. given the evidence, we failed to reject the hypothesis that cultivation expansion is contributing to increased soil and water externalities, since significant increases in cultivation on soils with severe erosion limitations were observed everywhere the externalities were documented. We discuss the case study results in terms of land use incentives (e.g., policy, economic, and biophysical), developing concepts of soil security, and ways to utilize case studies such as those presented to better communicate the value of soil and water resource conservation. Incorporating the tenets of soil potential and soil risk into soil health evaluations and cultivation decision-making is needed to better match the soil resource with land use and help avoid more extreme soil and water-related externalities.

关键词： Soil erosion Watershed runoff Soil potential Soil security Externality

Organic electrode materials for fast-rate,high-power battery applications

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Materials Reports(Energy) 2021年第1期1卷 4-25页

作者： Cara N.gannett Luis Melecio-Zambrano Monica Jo Theibault Brian M.Peterson Brett P.Fors hector D.Abruna Department of Chemistry and Chemical Biology Cornell UniversityIthacaNY14853USA

The development of new battery materials with fast charging/discharging capabilities is necessary to meet the growing demands of modern *** counter ion transport in inorganic materials(generally by de/intercalation)currently limits charge/discharge rates in lithium-ion batteries,the weak intermolecular forces in organic materials result in flexible,spacious structures that offer improved ion transport ***,we present the principles which enable fast rate capabilities in organic electrode materials,accompanied by specific literature examples illustrating exceptional rate *** discuss approaches to material design which support electron and/or ion transport and the limitations associated with each *** review aims to highlight the unique characteristics of organic materials as high-power density electrodes and inspire continued work in the field.

关键词： Energy storage Batteries Organic materials High-power Electrochemistry

Atrial-selective Inhibition of Sodium Channel Current by Wenxin Keli is Effective in Suppressing Atrial Fibrillation

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Atrial-selective Inhibition of Sodium Channel Current by Wen...