苜蓿培养细胞抗羟脯氨酸变异体的筛选和特性分析

以返地卫星搭载的苜蓿（ＭｅｄｉｃａｇｏｓａｔｉｖａＬ．）种子为实验材料,取其无菌苗下胚轴切段诱导愈伤组织,该愈伤组织经正筛选法,获得抗脯氨酸类似物Ｌ羟脯氨酸（Ｈｙｐ）的变异细胞系（Ｈｙｐｒ）．Ｈｙｐｒ脱离选择压力３ｍｏ后,对Ｈｙｐ的抗性仍比对照强,ＦＷ细胞内游离脯氨酸ｗ＝０．７２ｍｇ／ｇ,是ＣＫ的３．４３倍,同时还具有对ＮａＣｌ和ＰＥＧ的交叉抗性．和ＣＫ相比,Ｈｙｐｒ愈伤组织可溶性蛋白质ＳＤＳＰＡＧＥ图谱出现两条新多肽（Ｍｒ≈５６×１０３、３２×１０３）;其过氧化物酶同工酶谱中酶活性明显高于对照,并出现１条新带,酯酶同工酶酶谱中亦出现３条新带．这些特性分析表明,该变异细胞系对Ｈｙｐ的抗性是稳定的．     

原生质体转化构建有机磷农药降解工程菌

降解有机磷农药甲胺磷、敌敌畏和对硫磷的菌株地衣芽孢杆菌 Ｐ１２（ Ｂａｃｉｌｌｕｓｌｉｃｈｅｎｉｆｏｒｍｉｓ） 经溶菌酶处理获得原生质体,加入降解乐果的供体菌 Ｇ１ Ｄ Ｎ Ａ,经ρ（ Ｐ Ｅ Ｇ６ ０００） ＝ ３００ ｇ Ｌ－ １ 诱导,在液体再生培养基中振荡培养ｔ＝ ２０ ｈ ,使其恢复细胞壁后,离心收集菌体,涂布于含乐果的基础培养基上,经筛选得一转化子 Ｊ Ｐ Ｚ．其菌落形态明显不同于出发菌株,乐果平板连续传代１０ 次,性状保持稳定．在θ＝ ３０ ℃,１００ ｒ／ｍｉｎ 的培养条件下,３ ｄ 内对ρ（ 甲胺磷） ＝ ０ ．５ ｇ Ｌ－ １ ,ρ（ 敌敌畏） ＝ ０ ．２ ｇ Ｌ－ １ ,ρ（ 对硫磷） ＝ ０ ．１ ｇ Ｌ－ １ ,ρ（ 乐果） ＝ ０ ．３ ｇ Ｌ－ １ 的降解率分别为 Ｒｄ ＝ ７９ ．１ ％ ,４６ ．７ ％ ,２９ ．４ ％ 和４６ ．４ ％ ．     

H2O2对抗旱性不同玉米品种愈伤组织抗氧化系统的影响

两个玉米品种愈伤组织经１０－４ｍｏｌＬ－１、１０－３ｍｏｌＬ－１和１０－２ｍｏｌＬ－１Ｈ２Ｏ２处理３ｈ后,电解质泄漏率加大;Ｈ２Ｏ２和ＭＤＡ含量增加;ＡｓＡ和ＣＡＲ含量的减少．１０－４ｍｏｌＬ－１的Ｈ２Ｏ２处理对愈伤组织产生的氧化伤害较小．抗旱性较强品种ＰＡＮ６０４３愈伤组织的抗氧化酶（ＳＯＤ、ＰＯＤ、ＡＰ和ＧＲ）活性高于抗旱性较弱品种ＳＣ７０１,ＡｓＡ和ＣＡＲ含量的下降程度低于ＳＣ７０１．ＰＡＮ６０４３愈伤组织具有较强的抗Ｈ２Ｏ２能力,与含高活力抗氧化系统密切相关     

转化血型用蕃茄α－D－半乳糖苷酶的分离、纯化及理化性质

成熟蕃茄匀浆后，经硫酸铵盐析，ＤＥＡＥ－ＳｅｐｈａｄｅｘＡ－５０离子交换层析，ＳｅｐａｄｅｘＧ－１００凝胶过滤和Ｍｅｌｉｂｉｏｓｅ－Ａｇａｒｏｓｅ亲和层析，获得了α－Ｄ－半乳糖苷酶（Ｃ．Ｅ．３．２．１．１１）。酶制剂经ＰＡＧＥ检测为一条带；ＳＤＳ－Ｇ－ＰＡＧＥ测得酶Ｍｒ为３４０００；比活力５２．９Ｕ／ｍｇ·；提纯倍数为５２９０１产率为４５％．酶专－催化以α－Ｄ－半乳糖为末端ａ－（１，３）连接的糖苷键，以ＰＮＰＧ（对硝基苯－α－Ｄ－半乳糖昔）为废物，酶催化反应的Ｋｍ＝０．１１ｍｍｏｌ／Ｌ，Ｖｍａｘ为６７μｍｏｌ·ｍｇ１－·ｍｉｎ－１．ｔ稳定范是０～３５℃；ＰＨ稳定范围是４．０～７．０．最适ｐＨ为５．１．半乳糖是酶的竞争性抑制剂；Ｃｕ２＋、Ｚｎ２＋、Ｍｎ２＋、Ｆｅ３＋、Ａｇ＋和ＥＤＴＡ对酶活性无影响．纯酶制剂可作为Ｂ型血向Ｏ型血转化的工具酶液．     

不同消毒剂对水中脊髓灰质炎病毒灭活的比较

将脊髓灰质炎病毒（ Ｐｏｌｉｏ Ｖ） 及不同消毒剂投加到模拟水样中,按不同接触时间１ ,３ ,１０ ,３０ ｍｉｎ 取样,空斑定量． 当模拟水有机质含量 Ｃ Ｏ Ｄ 为２０ ｍｇ／ Ｌ,病毒浓度ｎ（ Ｐ Ｆ Ｕ） ≈１ ×１０５ ｍ Ｌ－ １ 时,分别投加氯制剂有效氯ρ（ Ｃｌ）１６ ｍｇ／ Ｌ,接触３０ ｍｉｎ ;ρ（ Ｃｌ Ｏ２） ＝ ８ ．０ ｍｇ／ Ｌ,３０ ｍｉｎ ; Ｃｌ＋ Ｃｌ Ｏ２ 联合消毒剂（５ ．０ ＋ ５ ．０） ｍｇ／ Ｌ,３０ ｍｉｎ ;ρ（ Ｏ３） ＝ １ ．２２ ｍｇ／ Ｌ,１０ ｍｉｎ 时;可使病毒彻底灭活． 它们使 Ｐｏｌｉｏ Ｖ 达到９９ ．９９ ％ 灭活的浓度时间乘积（ ρ×ｔ） 值分别是６６２ ．５ ,１２９ ．５ ,２００ ．０ 和３ ．２ ｍｇ Ｌ－ １ ｍｉｎ ． 消毒效果（ 顺序） 为 Ｏ３ ＞ Ｃｌ Ｏ２ ＞ Ｃｌ＋ Ｃｌ Ｏ２ ＞ Ｃｌ． 联合消毒灭活 Ｐｏｌｉｏ Ｖ 的效果为 Ｃｌ 的３ ．３ 倍,表明将 Ｃｌ 与 Ｃｌ Ｏ２ 联合应用具有协同效应,优于传统的单一加氯消毒方式     

吸水链霉菌井冈变种JG5008转化系统的初建

吸水链霉菌井冈变种ＪＧ５００８的最佳转化条件是：ＪＧ５００８在添加ＭｇＣｌ２（ｃｆ＝０．００５ｍｏｌ／Ｌ）和甘氨酸（ρｆ＝０．５ｇ／Ｌ）的含１０％蔗糖的ＹＥＭＥ培养基中接种浓度ｎ≈１０＾８ｍＬ＾－１的ＪＧ５００８孢子悬液，３７℃摇床培养１２ｈ，收获菌丝体。在３２℃、溶菌酶浓度ρ＝２ｍｇ／ｍＬ的条件下溶菌１ｈ后制备原生质体，用Ｔ缓冲液在Ｒ２ＹＥ培养基上进行转化。本文初步建立了ＪＧ５００８的质粒载体系     

化学诱变结合结构类似物法选育高苯丙氨酸解氨酶菌种

ＥＭＳ诱变结合结构类似物法提高含ＰＡＬ出发菌株红酵母Ｒｈｏｄｏｔｏｒｕｌａ ｓｐ．ＣＩＢＡＳＡ１４０１１００ 生物转化能力阳性率为３５．５ ％ ,部分突变株ＰＡＬ转化能力提高１ 倍以上,其中Ｅ１０５,Ｅ２４０ 具有快速转化能力,反应３ ｈＬＰｈｅ累积浓度达到１ ｇＬ左右．φ１０％ 甘油和３０ ｇＬＧｌｕ 对ＰＡＬ转化具有明显的稳定作用．用含φ１０％ 甘油和３０ ｇＬＧｌｕ 的反应液进行生物转化制备,Ｅ１０５ 和Ｅ２４０ 在２４ ｈ 期间ＬＰｈｅ 质量浓度大于２０ ｇＬ,转化率达８０ ％ ．     

LHG1菌株的分离和降解环己烷的研究

通过选择性培养从石油废水污染的土壤中分离出一株以环己烷为唯一碳源和能源的降解菌株 Ｌ Ｈ Ｇ１ ,对 Ｌ Ｈ Ｇ１ 菌株的降解特性进行了研究．确定 Ｌ Ｈ Ｇ１ 菌株最适培养条件为：培养时间６０ ～１００ ｈ 、环己烷浓度４６０ ～７７０ ｍｇ／ Ｌ、ｐ Ｈ６ ～８ 、ρ（ Ｎａ Ｃｌ） ＝ １０ ｇ Ｌ－ １ 、θ＝ ２５ ～４０ ℃． Ｌ Ｈ Ｇ１ 菌株能够利用环烷烃代谢的中间产物环己酮和环戊酮．此外, Ｌ Ｈ Ｇ１ 菌株还能降解液体石蜡、固体石蜡、萘和苯酚等链烃、芳香烃和酚类     

紫羊茅根中铜结合肽的分离和纯化

利用１次ＳｅｐｈａｄｅｘＧ５０凝胶过滤和２次ＱＡＥＳｅｐｈａｄｅｘＡ２５离子交换层析的方法,从最后６ｄ用ＣｕＣｌ２处理（ρ＝２０ｍｇ／Ｌ）、２０ｄ龄的紫羊茅（Ｆｅｓｔｕｃａｒｕｂｒａｃｖ．Ｍｅｒｌｉｎ）根中分离纯化了１个铜结合肽（ＣｕＢＰ２ａ）,该肽在ＳｕｐｅｒｄｅｘＰｅｐｔｉｄｅＨＲ１０／３０预装柱的ＦＰＬＣ凝胶过滤中在λ２５４ｎｍ处只出现一个峰,经分子量标准曲线估计,其Ｍｒ约为１４００,在ＤｅｌｔａＰａｋＣ１８的反相ＨＰＬＣ中,在λ２５４ｎｍ处也只有１个紫外吸收峰值,这都说明该肽已经达到了较高的的纯度．通过光谱分析,发现该肽的最大紫外吸收值在２４８．１ｎｍ处．对Ｃｕ结合物在植物体内的存在状态进行了讨论．     

几种胁迫因素对绞股蓝愈伤组织中皂甙积累的影响

将ＭＳ＋ρ（２,４Ｄ）０．５ｍｇ·Ｌ－１＋ρ（ＢＡ）１０ｍｇ·Ｌ－１培养基的Ｍｎ２＋浓度提高２０倍时可使绞胶蓝愈伤组织培养物的皂甙产率增加９１％,而提高Ｃｕ２＋浓度对皂甙积累的影响不显著;培养基中加入６８０ｍｍｏｌ·Ｌ－１的甘露醇可使皂甙产率提高８３％,但加入ＮａＣｌ则会降低皂甙产量;适当浓度的米曲霉和根霉提取物可使皂甙产率分别提高９７％和４２％．由ＴＬＣ图谱可见,绞股蓝愈伤组织中的皂甙组成与原植物相似,但出现一个新组分;原个别组分在不同的胁迫条件下有差别地消失．     

Importance of greater interdisciplinarity and geographic scope when tackling the driving forces behind biological invasions

Invasive non-native species are important drivers of ecosystem change, yet the driving forces of biological invasions themselves are poorly understood. Such information is essential to ensure policies focus on the most relevant drivers, and that future scenarios capture the full range of potential outcomes for invasive non-native species. I carried out a bibliometric analysis of articles published from 2000 to 2020 that address either invasive non-native species or biodiversity and ecosystem services and that also mention 1 or more drivers of ecosystem change. I examined 5 indirect drivers (demographic, economic, governance, sociocultural, and technological) and 6 direct drivers (climate change, invasive non-native species, land-use or sea-use change, natural hazards, pollution, and resource extraction). Using the Web of Science core collection of citation indexes, I undertook searches of article titles and keywords and retrieved 27,462 articles addressing invasive non-native species and 110,087 articles dealing with biodiversity or ecosystem services. Most research to date on biological invasions as well as on biodiversity and ecosystem services has focused on anthropogenic direct drivers of ecosystem change rather than indirect drivers. Yet currently, less than 18% of articles addressing biological invasions examined drivers of ecosystem change, a similar level to that found over 20 years ago for biodiversity or ecosystem services. Knowledge of the drivers of biological invasions is limited, emphasizes tractable drivers over those that require an interdisciplinary approach, and is biased toward developed economies. Drivers generally deemed important for biological invasions, such as governance and resource extraction, accounted for less than 2% of research effort. The absence of a systematic understanding of the forces that drive invasive non-native species and how they interact means that attempts to mitigate or forecast biological invasions are likely to fail. To address biological invasions requires a much better orientation of national and international research on drivers in relation to both their actual importance as well as their policy relevance.     

Mitigating the effects of climate change on the nests of sea turtles with artificial irrigation

For sea turtles, like many oviparous species, increasing temperatures during development threaten to increase embryonic mortality, alter offspring quality, and potentially create suboptimal primary sex ratios. Various methods are being implemented to mitigate the effects of climate change on reproductive success, but these methods, such as breeding programs, translocations, and shading, are often invasive and expensive. Irrigation is an alternative strategy for cooling nests that, depending on location, can be implemented relatively quickly and cheaply. However, multiple factors, including ambient conditions, nest substrate, and species characteristics, can influence irrigation success. Additionally, irrigation can vary in duration, frequency, and the volume of water applied to nests, which influences the cooling achieved and embryonic survival. Thus, it is critical to understand how to maximize cooling and manage risks before implementing irrigation as a nest-cooling strategy. We reviewed the literature on nest irrigation to examine whether artificial irrigation is feasible as a population management tool. Key factors that affected cooling were the volume of water applied and the frequency of applications. Embryonic responses varied with species, ambient conditions, and the timing of irrigation during development. Nest inundation was the key risk to a successful irrigation regime. Future irrigation regimes must identify clear targets, either primary or adult sex ratios, that maximize population viability. Monitoring population responses and adjusting the irrigation regime in response to population characteristics will be critical. Most studies reported on the manipulation of only one or two variables, further research is required to understand how altering multiple factors in an irrigation regime influences the cooling achieved and embryonic responses.     

Positive and Negative Effects of a Threatened Parrotfish on Reef Ecosystems

Species that are strong interactors play disproportionately important roles in the dynamics of natural ecosystems. It has been proposed that their presence is necessary for positively shaping the structure and functioning of ecosystems. We evaluated this hypothesis using the case of the world's largest parrotfish (Bolbometopon muricatum), a globally imperiled species. We used direct observation, animal tracking, and computer simulations to examine the diverse routes through which B. muricatum affects the diversity, dispersal, relative abundance, and survival of the corals that comprise the foundation of reef ecosystems. Our results suggest that this species can influence reef building corals in both positive and negative ways. Field observation and simulation outputs indicated that B. muricatum reduced the abundance of macroalgae that can outcompete corals, but they also feed directly on corals, decreasing coral abundance, diversity, and colony size. B. muricatum appeared to facilitate coral advancement by mechanically dispersing coral fragments and opening up bare space for coral settlement, but they also damaged adult corals and remobilized a large volume of potentially stressful carbonate sediment. The impacts this species has on reefs appears to be regulated in part by its abundance—the effects of B. muricatum were more intense in simulation scenarios populated with high densities of these fish. Observations conducted in regions with high and low predator (e.g., sharks) abundance generated results that are consistent with the hypothesis that these predators of B. muricatum may play a role in governing their abundance; thus, predation may modulate the intensity of the effects they have on reef dynamics. Overall our results illustrate that functionally unique and threatened species may not have universally positive impacts on ecosystems and that it may be necessary for environmental managers to consider the diverse effects of such species and the forces that mediate the strength of their influence. Efectos Positivos y Negativos de un Pez Loro Amenazado Sobre Ecosistemas Arrecifales     

Form-specific fragances fromOphrys insectifera L. (Orchidaceae) attract species of different pollinator genera. Evidence of sympatric speciation?

Two closely related forms ofOphrys insectifera were observed in the field to attract different pollinator species selectively.O. i. ssp.insectifera attracted males of two species ofArgogorytes (Sphecidae, Hymenoptera Aculeata) andO. i. ssp.aymoninii attractedAndrena combinata males (Andrenidae, Apoidea, Hymenoptera Aculeata). A third form,O. aff.i. ssp.insectifera, attracted none of these three species. Volatile compounds from flowers and inflorescences of the three forms (originating from Öland, Sweden, and Aveyron, France) were collected, using entrainment, enfleurage, and solvent extraction techniques, and identified by gas chromatography — mass spectrometry. Scent differences between the three forms were confirmed in the amounts of aliphatic hydrocarbons (C₁₁–C₁₉), methyl esters (C₁₄–C₁₈), short chain aliphatic 1-alcohols (C₆–C₁₂), and monoterpene alcohols (C₁₀).     

Estimation of the surface stress from the streamwise pressure gradient: The Kármán Integral Momentum Equation revisited

A method is developed to estimate the stress at the surface in a portable wind tunnel for wind erosion studies. The boundary layer height and the pressure gradient are used in a simple expression from the Kármán Integral Momentum Equation. Values of friction velocity u _* are within 10% of experimental values obtained through correlation techniques, including measurements of differential pressures with the Murdoch Turbulence Probe MTP and the X-wire, hot-wire anemometer XWA. Wind velocity and stress profiles reveal logarithmic trends and a constant stress layer near the surface in the DAWA portable wind tunnel. Realignment of the statistics with the mean wind is essential.     

Using decision science to evaluate global biodiversity indices

Global biodiversity indices are used to measure environmental change and progress toward conservation goals, yet few indices have been evaluated comprehensively for their capacity to detect trends of interest, such as declines in threatened species or ecosystem function. Using a structured approach based on decision science, we qualitatively evaluated 9 indices commonly used to track biodiversity at global and regional scales against 5 criteria relating to objectives, design, behavior, incorporation of uncertainty, and constraints (e.g., costs and data availability). Evaluation was based on reference literature for indices available at the time of assessment. We identified 4 key gaps in indices assessed: pathways to achieving goals (means objectives) were not always clear or relevant to desired outcomes (fundamental objectives); index testing and understanding of expected behavior was often lacking; uncertainty was seldom acknowledged or accounted for; and costs of implementation were seldom considered. These gaps may render indices inadequate in certain decision-making contexts and are problematic for indices linked with biodiversity targets and sustainability goals. Ensuring that index objectives are clear and their design is underpinned by a model of relevant processes are crucial in addressing the gaps identified by our assessment. Uptake and productive use of indices will be improved if index performance is tested rigorously and assumptions and uncertainties are clearly communicated to end users. This will increase index accuracy and value in tracking biodiversity change and supporting national and global policy decisions, such as the post-2020 global biodiversity framework of the Convention on Biological Diversity.     

Assessing the extent and nature of wildlife trade on the dark web

Use of the internet as a trade platform has resulted in a shift in the illegal wildlife trade. Increased scrutiny of illegal wildlife trade has led to concerns that online trade of wildlife will move onto the dark web. To provide a baseline of illegal wildlife trade on the dark web, we downloaded and archived 9852 items (individual posts) from the dark web, then searched these based on a list of 121 keywords associated with illegal online wildlife trade, including 30 keywords associated with illegally traded elephant ivory on the surface web. Results were compared with items known to be illegally traded on the dark web, specifically cannabis, cocaine, and heroin, to compare the extent of the trade. Of these 121 keywords, 4 resulted in hits, of which only one was potentially linked to illegal wildlife trade. This sole case was the sale and discussion of Echinopsis pachanoi (San Pedro cactus), which has hallucinogenic properties. This negligible level of activity related to the illegal trade of wildlife on the dark web relative to the open and increasing trade on the surface web may indicate a lack of successful enforcement against illegal wildlife trade on the surface web.     

Estimating freshwater turtle mortality rates and population declines following hook ingestion

Freshwater turtle populations are susceptible to declines following small increases in the mortality of adults, making it essential to identify and understand potential threats. Freshwater turtles ingest fish hooks associated with recreational angling, and this is likely a problem because hook ingestion is a source of additive mortality for sea turtles. We used a Bayesian‐modeling framework, observed rates of hook ingestion by freshwater turtles, and mortality of sea turtles from hook ingestion to examine the probability that a freshwater turtle in a given population ingests a hook and subsequently dies from it. We used the results of these analyses and previously published life‐history data to simulate the effects of hook ingestion on population growth for 3 species of freshwater turtle. In our simulation, the probability that an individual turtle ingests a hook and dies as a result was 1.2–11%. Our simulation results suggest that this rate of mortality from hook ingestion is sufficient to cause population declines. We believe we have identified fish‐hook ingestion as a serious yet generally overlooked threat to the viability of freshwater turtle populations.     

Content analysis of newspaper coverage of the Florida panther

Populations of large carnivores are declining globally, and analysis of public discourse about carnivores is useful for understanding public opinion and influences on management and policy. Portrayal of carnivores in the media affects public perceptions and support for their conservation. We conducted a content analysis of 513 articles about Florida panthers (Puma concolor coryi) published from 2003 to 2006 in newspapers with local circulation in core panther habitat in southwest Florida and papers with statewide circulation to compare the differences in the amount of coverage and portrayals of panther risks to people and property on the basis of proximity of human communities to panthers. Local papers published significantly more news articles and significantly longer news articles primarily about panthers. Articles in local and statewide papers used both episodic frames, which focus on specific occurrences (e.g., a panther sighting or predation) and thematic frames, which focus on general trends (e.g., abundance of panthers over time). Local articles more often emphasized risks that panthers might harm people, pets, or livestock than statewide papers. Our results are consistent with theory that proximity to human-carnivore conflict influences perceptions and salience of risks posed by large carnivores. Most articles mentioned panthers as a secondary topic, which we believe was a result of the relevance an endangered carnivore has in discussions of public land management, development, and regulations in Florida. Claims made by sources quoted in each article had a neutral to positive depiction of panthers, and most quotations were from federal and state agency scientists. We suggest continued use by the media of agency sources provides the opportunity for clear, concordant messages about panther management. Content analysis provides a way to monitor media portrayal of carnivores for consistency with agency outreach goals.