Hydraulic properties and drought response of a tropical bamboo (Cephalostachyum pergracile)

Bamboo plants are an essential component of tropical ecosystems,yet their vulnerability to climate extremes,such as drought,is poorly understood due to limited knowledge of their hydraulic properties.Cephalostachyum pergracile,a commonly used tropical bamboo species,exhibited a substantially higher mortality rate than other co-occurring bamboos during a severe drought event in 2019,but the underlying mechanisms remain unclear.This study investigated the leaf and stem hydraulic traits related to drought responses,including leaf-stem embolism resistance(P50leaf;P50stem) estimated using optical and X-ray microtomography methods,leaf pressure-volume and water-releasing curves.Additionally,we investigated the seasonal water potentials,native embolism level(PLC) and xylem water source using stable isotope.We found that C.pergracile exhibited strong resistance to embolism,showing low P50leaf,P50stem,and turgor loss point,despite its rapid leaf water loss.Interestingly,its leaves displayed greater resistance to embolism than its stem,suggesting a lack of effective hydraulic vulnerability segmentation(HVS) to protect the stem from excessive xylem tension.During the dry season,approximately 49% of the water was absorbed from the upper 20-cm-deep soil layer.Consequently,significant diurnal variation in leaf water potentials and an increase in midday PLC from 5.87±2.33% in the wet season to 12.87±4.09%in the dry season were observed.In summary,this study demonstrated that the rapid leaf water loss,high reliance on surface water,and a lack of effective HVS in C.pergracile accelerated water depletion and increased xylem embolism even in the typical dry season,which may explain its high mortality rate during extreme drought events in 2019.

A Century of Spinosaurs-A Review and Revision of the Spinosauridae with Comments on Their Ecology

The spinosaurids represent an enigmatic and highly unusual form of large tetanuran theropods that were first identified in 1915.A recent flurry of discoveries and taxonomic revisions of this important and interesting clade has added greatly to our knowledge.Spinosaur body fossils are however generaUy rare and most species are known from only limited skeletal remains.Their unusual anatomical adaptations to the skull,limbs and axial column all differ from other large theropods and point to an unusual ecological niche and a lifestyle intimately linked to water.

A Review of the Taxonomy and Palaeoecology of the Anurognathidae(Reptilia,Pterosauria)

The anurognathids are an enigmatic and distinctive clade of small,non-pterodactyloid pterosaurs with an unusual combination of anatomical traits in the head,neck,wings and tail.They are known from very limited remains and few have been described in detail,and as a result,much of their biology remains uncertain.This is despite their importance as potentially one of the earliest branches of pterosaur evolution or even lying close to the origins of pterodactyloids.This review covers the taxonomy and palaeoecology of the anurognathids,which remain an interesting branch of pterosaurian evolution.

Presence of Acanthamoeba spp.in water purification plants in southern England

Objective:To identify the prevalence of Acanthamoeba in drinking water treatment plants during the course of the purification processes.Methods:Samples were taken from two drinking water purification plants and monitored for the presence of Acanthamoeba in order to estimate the removal capacity of treatment methods employed. Water samples were collected at each step in the purification,during the one year survey,and analysed for the presence of Acanthamoeba spp.by plating on bacterial-seeded plates.Results:The results showed that amoebae were present in surface raw waters in 100%of the samples tested.Acanthamoeba spp.were isolated from 71%and 57%of the water samples collected from post flat-bottom clarifier 1 and post-sedimentation plant respectively.Considering the outflow drinking waters,the removal capacity was 100%in both purification plants monitored.The occurrence of Acanthamoeba was not associated with seasonality.Conclusion: These findings confirm that water purification plants employing methods of flocculation,sedimentation,and filtration in combination with activated charcoal filtration,ozonisation and chlorination exhibited sufficient Acanthamoeba removal capacity and the presence of amoebae in the tap water may be due to older plumbing,water storage tanks,tap water hygiene,and/or environmental settings.

Towards a Standardized Approach of Cetacean Habitat: Past Achievements and Future Directions

The understanding of what habitat means for an organism as well as the underlying factors driving patterns of habitat use is still unknown for many species. Cetacean habitat has been described using a range of methodologies and variables measured over various temporal and spatial scales?that are often author-dependent. However, in order to develop an objective and sound understanding of what habitat actually means for cetaceans, a standardized approach needs to be developed. Here, after briefly reviewing the fundamental differences between terrestrial and marine habitats, we highlight the difficulty in defining a marine habitat, with a special focus on marine mammals. We subsequently provide six recommendations by which future cetacean habitat studies might be approached. This recommended approach aims to amend the way in which we think about and undertake investigations into cetacean habitat. It is believed that through this broadened approach, future cetacean habitat studies will increase our understanding of underlying driving factors of cetacean habitat, rather than just describing distribution patterns. Finally, it is stressed how the proposed approach will be more directly applicable within management frameworks and of benefit to conservation initiatives.

Convergent relationships between flower economics and hydraulic traits across aquatic and terrestrial herbaceous plants

Maintaining open flowers is critical for successful pollination and depends on long-term water and carbon balance.Yet the relationship between how flower hydraulic traits are coordinated in different habitats is poorly understood.Here,we hypothesize that the coordination and trade-offs between floral hydraulics and economics traits are independent of environmental conditions.To test this hypothesis,we investigated a total of 27 flower economics and hydraulic traits in six aquatic and six terrestrial herbaceous species grown in a tropical botanical garden.We found that although there were a few significant differences,most flower hydraulics and economics traits did not differ significantly between aquatic and terrestrial herbaceous plants.Both flower mass per area and floral longevity were significantly positively correlated with the time required for drying full-hydrated flowers to 70%relative water content.Flower dry matter content was strongly and positively related to drought tolerance of the flowers as indicated by flower water potential at the turgor loss point.In addition,there was a trade-off between hydraulic efficiency and the construction cost of a flower across species.Our results show that flowers of aquatic and terrestrial plants follow the same economics spectrum pattern.These results suggest a convergent flower economics design across terrestrial and aquatic plants,providing new insights into the mechanisms by which floral organs adapt to aquatic and terrestrial habitats.

Pterosaur Research:Recent Advances and a Future Revolution

In the years since the first description of a pterosaur specimen in 1784, pterosaur research has inevitably advanced considerably. However the last decade has arguably seen a much greater increase in our knowledge than the preceding two centuries. Since the turn of the new millennium, more than 40 new pterosaur genera and species have been described and whole new clades have been discovered, in addition to much new data being developed on pterosaur anatomy, functional morphology, palaeobiology, systematics, ecology and more. We are perhaps at the start of a golden age of pterosaur research and much as the dinosaurs underwent a revolution in the 1970s through to the early 1990s, now the Pterosauria are taking their turn. There is also a new and wider interest in pterosaur work as it attracts both more researchers and greater public interest. Pterosaurs appear to be an increasingly popular aspect of paleontology in popular culture and of interest to the media, both mainstream and digital.

Oxidation of norbornadiene:Theoretical investigation on H-atom abstraction and related radical decomposition reactions

The chemical kinetics of hydrogen atom(H-atom)abstraction reactions from norbornadiene(NBD)by five radicals(H,O(^(3)P),OH,CH_(3),and HO_(2)),and the unimolecular reactions of three NBD derived radicals,were studied through high-level ab-initio calculations.The geometries optimization and vibrational frequencies calculation for all the reactants,transition states,and products were obtained at the M06-2X/6-311ttG(d,p)level of theory.The zeropoint energy(ZPE)corrected potential energy surfaces(PESs)were determined at the QCISD(T)/cc-pVDZ,TZ level of theory with basis set corrections from MP2/cc-pVDZ,TZ,QZ methods for single point energy calculations.Conventional transition state theory(TST)was used for the rate constants calculations of H-atom abstraction reactions by five radicals(H,O(^(3)P),OH,CH_(3),and HO_(2))at temperatures from 298.15 to 2000 K,while the a-site H-atom abstraction reaction rate constant of NBD by OH radical has been obtained through variational transition state theory(VTST).The results show that the H-atom abstraction reactions from the α-carbon atom of NBD are the most critical channels at low temperatures.Total rate constants for H-atom abstraction reactions by OH radical are also the fastest among all of the reaction channels investigated at the temperature range from 298.15 to 2000 K.Rice-Ramsperger-Kassel-Marcus/Master Equation(RRKM/ME)has been used to calculate the pressure-and temperature-dependent rate constants for the unimolecular reactions of three related C7H7 product radicals which generated from H-atom abstraction reaction within temperature ranges of 300-2000 K and pressures of 0.01-100 atm.A combination of composite methods has been used to calculate the temperature-dependent thermochemical properties of NBD and related radicals.All the calculated kinetics and thermochemistry data can be utilized in the model development for NBD oxidation.

砷对NIH 3T3细胞谷胱甘肽水平、相关酶活性及其基因表达的影响

[目的]探讨急性、慢性砷暴露对小鼠成纤维细胞 (NIH3T3细胞 )氧化还原状态的影响 ,进而探讨其对细胞谷胱甘肽 (GSH)水平、相关酶活性及其基因表达的影响。[方法]将经过不同浓度砷处理的细胞 ,抽提细胞总蛋白。采用经过改进的Clark法测定细胞中谷胱甘肽 ;采用Thomas法测定谷胱甘肽还原酶 (GR)活性 ;使用分光光度法测定谷胱甘肽与1 氯 2 ,4 二硝基苯 (CDNB)的结合以确定谷胱甘肽转移酶 (GST)活性。采用SDS聚丙烯酰胺凝胶电泳和固定化蛋白质的免疫学测定法测定血红素氧化酶 (HO 1)蛋白表达 ;采用RNA印迹法测定谷胱甘肽还原酶 (GR)和谷胱甘肽过氧化物酶(GSH Px)的基因表达。[结果]急性砷处理细胞在较低浓度范围可以引起GSH水平的增加 ;而当砷浓度高于25μmol/L时 ,GSH水平降低 ;在0.1和0.5 μmol/L慢性染毒之后细胞GSH水平明显降低。然而 ,在急性和慢性砷处理组GST和GR的活性均有升高 ,而在高浓度24h处理组则显著降低 ;GR的mRNA水平与GR的活性相一致 ,在急、慢性染毒组中均表现为GR的mRNA表达上调 ;砷可以引起血红素氧化酶 1(HO 1)蛋白水平的增加。急性、慢性砷处理均引起GSH Px mRNA表达下调。[结论]三价砷可以引起氧化应激、GSH水平改变、以及相关酶活性及其基因表达的改变 ,急性与慢性砷接触对GSH系统?

不同木柴在两种条件下燃烧生成的颗粒物中多环芳烃的排放特性研究

将马尾松、赤桉、甜叶桉树和锦熟黄杨四种木柴,使用普通家用木柴燃烧加热炉在两种条件下进行燃烧,采集燃烧所排放的颗粒物样品并分析,获得了颗粒物中多环芳烃(Polycyclic Aromatic Hydrocarbons简写为PAHs)的排放因子及单个多环芳烃化合物的分布规律。结果显示:在颗粒物中检测出的多环芳烃化合物主要是分子量较大并被称为基因致毒性类的多环芳烃化合物,实验还发现:在四种木柴中,马尾松具有最高的多环芳烃化合物的排放因子,其次是赤桉和锦熟黄杨,最低的是甜叶桉树。两种不同的燃烧条件相比,慢燃烧比快燃烧所产生的总多环芳烃化合物和基因致毒性多环芳烃化合物的量都要高。

枯草杆菌ylmK基因的荧光标记及Ylmk蛋白的亚细胞定位

目的:对枯草杆菌ylmK基因进行3'端荧光标记以便对其产物YlmK蛋白在菌体中的位置进行初步观察。方法:以BS168菌株基因组DNA为模板,PCR扩增ylmK基因的3'端序列,并将其克隆到载体pSG1164中,形成ylmK'-gfpmutl融合,构建重组载体pNG424;将pNG424转化枯草杆菌168菌株,单交换形成完整的功能性3'端gfpmutl标记的ylmK基因,菌落PCR对阳性转化子BS362进行鉴定,用表面荧光显微镜技术对BS362进行观察。结果:荧光检测结果表明GFP标记的YlmK分布于菌体的外周,在位置上靠近细胞膜并与之平行排列。结论:YlmK是一种膜蛋白。

YlyA和RNA聚合酶的反应性鉴定

目的:用亲和层析法鉴定YlyA与RNA聚合酶(RNAP)的结合性能。方法:将YlyA分别上样于以Affigel15为亲和介质制备的空白柱、牛血清白蛋白(BSA)柱和RNAP柱;以GreA和绿色荧光蛋白(GFP)为阳性和阴性对照蛋白分别上样于同一RNAP柱,洗涤和洗脱缓冲液(pH均为7.9)的盐离子浓度分别为30 mmol/L和400 mmol/L;用免疫印迹法对洗涤和洗脱流出液中的YlyA进行检测。结果:在空白柱和BSA柱的洗脱收集液中,没有检测到YlyA,大量的YlyA出现在了洗涤收集液中;而在RNAP柱的洗脱收集液中,检测到了YlyA和GreA,没有检测到GFP。结论:YlyA与RNAP之间具有特异性结合能力,为YlyA极有可能是一种转录因子的生物信息学分析结果提供了实验证据。

Bio-inspired carbon electro-catalysts for the oxygen reduction reaction

We report the synthesis, characterisation and catalytic performance of two nature-inspired biomassderived electro-catalysts for the oxygen reduction reaction in fuel cells. The catalysts were prepared via pyrolysis of a real food waste(lobster shells) or by mimicking the composition of lobster shells using chitin and CaCO_3 particles followed by acid washing. The simplified model of artificial lobster was prepared for better reproducibility. The calcium carbonate in both samples acts as a pore agent, creating increased surface area and pore volume, though considerably higher in artificial lobster samples due to the better homogeneity of the components. Various characterisation techniques revealed the presence of a considerable amount of hydroxyapatite left in the real lobster samples after acid washing and a low content of carbon(23%), nitrogen and sulphur(<1%), limiting the surface area to 23 m^2/g, and consequently resulting in rather poor catalytic activity. However, artificial lobster samples, with a surface area of ≈200 m^2/g and a nitrogen doping of 2%, showed a promising onset potential, very similar to a commercially available platinum catalyst, with better methanol tolerance, though with lower stability in long time testing over 10,000 s.

Tunnel geometry of the subterranean termite Reticulitermes grassei （Isoptera： Rhinotermitidae）in response to sand bulk density and the presence of food

地下的白蚁的神秘习惯限制他们的 foraging 模式原位的详细分析，但是过程是显然由连接巢，木质的资源在每个殖民地的领土以内发现了的隧道构造统治了。在这研究，掘形成，取向在白蚁 Reticulitermes grassei (Clcbment ) 试验性地被学习，用包含象基础的细砂的 2-dimensional 实验室 foraging 竞技场。在一个 10 天的时期和产生网络的几何学上的探索隧道的大楼被描述。分数维的分析证明那隧道几何学有一种分数维的尺寸，不管掘的全部的长度是否因为蒸化机遇到了食物来源。在竞技场的沙的体积密度影响了掘的距离，与减少建设的更高的密度，但是没影响隧道几何学。隧道 discernibly 没关于放食物来源被面向，甚至处于白蚁没能发现在不到 50 公里的距离的食物来源的一种状况，建议从木头的 volatiles 不是引诱剂。

Dissecting the Native Architecture and Dynamics of Cyanobacterial Photosynthetic Machinery

房间膜的结构的动力学和灵活性在房间的功能起基本作用，即，发信号，精力 transduction，和生理的改编。cyanobacterial thylakoid 膜代表能同时进行氧的光合作用和呼吸的模型膜。在这研究，我们从模型 cyanobacterium 在 thylakoid 膜进行了光合的建筑群的全球组织和活动性的直接可视化， Synechococcus elongatus PCC 7942 用高分辨率的原子力量，共焦、全部的内部思考荧光显微镜学。我们设想了本国的安排并且 photosystem 的稠密的收拾行李我(希腊语的第二十三个字母) ， photosystem II (PSII ) ，和细胞色素(Cyt ) b 6 在在分子的水平的 thylakoid 膜以内的 f。而且，我们机能上地标注了希腊语的第二十三个字母， PSII， Cyt b 6 f，和 ATP synthase 个别地与荧光灯蛋白质，并且揭示了这四光合的建筑群的异构的分发并且用实时房间的荧光成像在拥挤的膜环境以内决定了他们的动态特征。我们在 thylakoid 膜描绘了红导致光的聚类本地化和光合的建筑群的可调节的散开，响应环境变化的光合的仪器的重组的代表。理解光合的膜的组织和动力学是必要的让人工的光合的系统的合理设计和建设支撑 bioenergy 开发。cyanobacterial thylakoid 膜的知识能也被扩大到另外的房间膜，例如叶绿体和 mitochondrial 膜。

Axogenesis in the central and peripheral nervous system of the amphipod crustacean Orchestia cavimana

We describe the formation of the major axon pathways in the embryonic central and peripheral nervous systems of the amphipod crustacean Orchestia cavimana Heller,1865 by means of antibody staining against acetylated alphatubulin.The data add to a long list of previous studies of various other aspects of development in Orchestia and provide a basis for future studies of neurogenesis on a deeper cellular and molecular level.Orchestia exhibits a tripartite dorsal brain,which is a characteristic feature of euarthropods.Its anlagen are the first detectable structures in the developing nervous system and can be traced back to distinct neuronal cell clusters in the early embryo.The development of the ventral nervous system proceeds with an anteroposterior gradient of development.In each trunk segment,the longitudinal connectives and the anterior commissure form first,followed by the intersegmental nerve,the posterior commissure and segmental nerves,respectively.A single commissure of a vestigial seventh pleonal segment is found.In the peripheral nervous system we observe a spatial and temporal pattern of leg innervation,which is strikingly similar in both limb types,the uniramous pereopods and the biramous pleopods.A proximal leg nerve splitting distally into two separated nerves probably reflects a general feature of crustaceans.

Epithelial-mesenchymal Plasticity in Breast Cancer Metastasis

Transitions between epithelial and mesenchymal states, which we have termed Epithelial Mesenchymal Plasticity (EMP), are

Microbial electrosynthesis of acetate from CO_(2)in three-chamber cells with gas diffusion biocathode under moderate saline conditions

The industrial adoption of microbial electrosynthesis(MES)is hindered by high overpotentials deriving from low electrolyte conductivity and inefficient cell designs.In this study,a mixed microbial consortium originating from an anaerobic digester operated under saline conditions(∼13 g L^(−1)NaCl)was adapted for acetate production from bicarbonate in galvanostatic(0.25 mA cm^(−2))H-type cells at 5,10,15,or 20 g L^(−1)NaCl concentration.The acetogenic communities were successfully enriched only at 5 and 10 g L^(−1)NaCl,revealing an inhibitory threshold of about 6 g L^(−1)Na^(+).The enriched planktonic communities were then used as inoculum for 3D printed,three-chamber cells equipped with a gas diffusion biocathode.The cells were fed with CO_(2)gas and operated galvanostatically(0.25 or 1.00 mA cm^(−2)).The highest production rate of 55.4 g m^(−2) d^(−1)(0.89 g L^(−1)d^(−1)),with 82.4%Coulombic efficiency,was obtained at 5 g L^(−1)NaCl concentration and 1 mA cm^(−2)applied current,achieving an average acetate production of 44.7 kg MWh−1.Scanning electron microscopy and 16S rRNA sequencing analysis confirmed the formation of a cathodic biofilm dominated by Acetobacterium sp.Finally,three 3D printed cells were hydraulically connected in series to simulate an MES stack,achieving three-fold production rates than with the single cell at 0.25 mA cm^(−2).This confirms that three-chamber MES cells are an efficient and scalable technology for CO_(2)bio-electro recycling to acetate and that moderate saline conditions(5 g L^(−1)NaCl)can help reduce their power demand while preserving the activity of acetogens.