Easier detection of invertebrate identification-key characters with light of different wavelengths

Evolutionary arms-races between avian brood parasites and their hosts have typically resulted in some spectacular adaptations, namely remarkable host ability to recognize and reject alien eggs and, in turn, sophisticated parasite egg mimicry. In a striking contrast to hosts sometimes rejecting even highly mimetic eggs, the same species typically fail to discriminate against highly dissimilar parasite chicks. Understanding of this enigma is still hampered by the rarity of empirical tests - and consequently evidence - for chick discrimination. Recent work on Australian host-parasite systems (Gerygone hosts vs. Chalcites parasites), increased not only the diversity of hosts showing chick discrimination, but also discovered an entirely novel host behavioural adaptation. The hosts do not desert parasite chicks (as in all previously reported empirical work) but physically remove living parasites from their nests. Here, I briefly discuss these exciting findings and put them in the context of recent empirical and theoretical work on parasite chick discrimination. Finally, I review factors responsible for a relatively slow progress in this research area and suggest most promising avenues for future research.     

不同光环境对粘虫生长发育的影响

【目的】研究不同光环境条件对粘虫Mythimna separata生长发育存活的影响,探讨影响粘虫生存的关键光环境因子,揭示昆虫对光环境的适应能力,为粘虫发生分布情况进行准确预测提供实验依据。【方法】选取特定波长和光强的LED灯作为供试光源,以不同发育阶段粘虫为供试昆虫,测定10种供试光源条件下粘虫各发育阶段的存活与发育情况。【结果】365nm波长光源照射能显著降低粘虫卵孵化率,比对照组卵孵化率降低了50.33%;420 nm波长光源照射能显著降低粘虫幼虫存活率、幼虫化蛹率和蛹羽化率,且能延长幼虫期和蛹期,比对照组幼虫存活率、化蛹率和蛹羽化率分别降低了72.00%、65.67%和72.87%,比对照组幼虫期和蛹期分别延长了12 d和11.4 d;420 nm和460 nm波长光源照射能显著降低粘虫成虫存活率,比对照组成虫存活率分别降低了44.44%%和40.00%。【结论】光强1000lx,波长365、420、460 nm的光环境能够抑制粘虫的生长发育,不利于粘虫生存。     

Effectiveness of light of different wavelengths to induce chlorophyll biosynthesis in rapidly and slowly greening tissues

Action spectra for light-induced chlorophyll formation in etiolated leaves, potato tubers, and dark-grown epi- and hypocotyls of pea and bean seedlings show a correlation between rate of greening and wavelengths with the strongest greening effect. Action spectra for the greening of leaves and the upper parts of epi- and hypocotyls with rapid greening and with rather high concentrations of protochlorophyll_650–652 have a maximum at 650 nm. While those for slowly greening material such as potato tuber parenchyma and the lower parts of epi- and hypocotyls show maxima around 660-–70 nm. This shift is discussed and it is proposed to be due to a more dominating role of light absorbed by phytochrome for the formation of chlorophyll precursors in slowly greening materials than in rapidly greening tissues. in which the protochlorophyll formation is rapid also without the influence of phytochrome. Therefore, in slowly greening material, the peak in the absorption spectrum for phytochrome in its red absorbing form will have a more dominating influence on the shape of the action spectrum, and this will be reflected in a shift of the peak from 650 nm to higher wavelengths.     

One "different kind of gentleman": Alfred Merle Norman (1831–1918), invertebrate zoologist

Alfred Merle Norman (1831–1918), an active clergyman in rural Co. Durham, England, came from an ancient Somerset family. He began to study marine biology during the early 1850s and during the 1860s was an important participant in John Gwyn Jeffreys' expeditions to the Shetland Islands. Norman's field collecting all over the British Isles was extensive and he made important trips to Norwegian fjords for dredging. His best known discoveries were Rhabdopleura and Synagoga , but he published major work on Protozoa, Porifera, Coelenterata, Mollusca, Crustacea, Echinodermata and other invertebrates. The publication Museum Normanianum summarized Norman's collection of 11,086 species, which was acquired by the British Museum (Natural History). His library, which incorporated John Gwyn Jeffreys' library on molluscs, is now in the Department of Zoology, Cambridge University. Norman was primarily a taxonomist secondarily interested in zoogeography who avoided Darwinian controversies.
A bibliography of Norman's 218 publications is included.     

Facile conversion of RNA aptamers to modular fluorescent sensors with tunable detection wavelengths

A GTP aptamer was converted to a modular fluorescent GTP sensor by conjugation of RRE (Rev responsive element) RNA and successive complex formation with a fluorophore-modified Rev peptide. Structural changes associated with substrate binding in the RNA aptamer were successfully transduced into changes in fluorescence intensity because of the modular structure of ribonucleopeptides. A simple modular strategy involving conjugation of a fluorophore-modified ribonucleopeptide to the stem region of an RNA aptamer deduced from secondary structural information helps produce fluorescent sensors, which allow tuning of excitation and detection wavelengths through the replacement of the fluorophore at the N-terminal of the Rev peptide.     

The efficiency of blood photomodification with therapeutic doses of optical radiation of different wavelengths

Biophysics - Spectra of radiation penetration depth into the blood and skin tissues were calculated for the wavelength range of 405 to 950 nm with the optical properties of biological tissues taken...     

Phototropin 1 and cryptochrome action in response to green light in combination with other wavelengths

Genetic studies have shown the effects of various photoreceptors on early photomorphogenic processes, defining the precise time course of red (RL), far-red (FrL) and blue light (BL) action. In this study, the effect of green wavebands in conjunction with these responses is examined. Longer-term (end point; 24–96 h) analysis of hypocotyl elongation in enriched green environments shows an increase in growth compared to seedlings under blue, red or both together. The effect was only observed at lower fluence rates (<10 μmol/m² s). Genetic analyses demonstrate that cryptochromes are required for this GL effect, consistent with earlier findings, and that the phy receptors have no influence. However, analysis of early (minutes to hours) stem growth kinetics indicates that GL cannot reverse the cryptochrome-mediated BL effect during early stem growth inhibition, and instead acts additively with BL to drive cryptochrome-mediated inhibition. Green light (GL) treatments antagonize RL and FrL-mediated hypocotyl inhibition. The GL opposition of RL responses persists in phyA, phyB, cry1cry2 and phot2 mutants. The response requires phot1 and NPH3, suggesting that this is not a GL response, but instead a response to extremely low-fluence rate BL. Tests with dim BL (<0.1 μmol/m² s) confirm a previously uncharacterized phot1-dependent promotion of stem growth, opposing the effects of RL. These findings demonstrate how enriched green environments may adjust RL and BL photomorphogenic responses through both the crys and phot1 receptors, and define a new role for phot1 in stem growth promotion.     

Effects of different photoperiods and wavelengths of light on the life-history traits of an aphidophagous ladybird, Coelophora saucia (Mulsant)

Abstract:  The influence of three photoperiods, viz. short day [8 : 16 h; light : dark (L : D)], long day (16 : 8 h; L : D) and continuous light (24 : 0 h; L : D) and four wavelengths of light, viz. white (control), yellow, blue and red on pre-imaginal development and reproductive performance of a ladybird, Coelophora (= Lemnia ) saucia (Mulsant) (Col., Coccinellidae) have been investigated under laboratory conditions. Long-day photoperiod and white light resulted in low immature stage mortality. Total larval period was longest under short-day and red-light conditions. Females kept at long-day photoperiod and under white light showed better reproductive performance than those placed under other photoperiods and wavelengths.     

The responses of a lotic mayfly Nousia sp. (Ephemeroptera: Leptophlebiidae) to moving water and light of different wavelengths

1. Although laboratory studies of the behaviour of aquatic macroinvertebrates are common, there has been little critical evaluation of the importance of test conditions to them. We used a common Australian leptophlebiid mayfly, Nousia sp., to investigate responses to light, wavelength of light, presence or absence of cover and still or flowing water.
2. Nousia sp. showed substantial qualitative differences in behaviour, as measured by movement, when there was no refuge (in the form of a crevice beneath a tile) present in the experimental arena.
3. We found no evidence of diel periodicity in activity in Nousia sp.
4. Nousia sp. did not respond to infra-red, red or green light at a flux density of 18–19 μmol m^–2 s^–1.
5. Nymphs were three times more likely to remain stationary in flowing water (mean velocity 0.10 m s^–1) than in still water.
6. We conclude that generalized assumptions about test conditions for experiments designed to quantify laboratory behaviour in benthic macroinvertebrates are unjustified and that evaluation of the individual requirements of test species should be conducted routinely.     

Effects of different light wavelengths at equal irradiance on testis weight, protein content, and K-paranitrophenylphosphatase activity in the Syrian hamster

The effects of different light wavelengths at equal irradiance on testis weight, testis protein content, and testis K-paranitrophenylphosphatase (K-pNPPase) activity were studied in the Syrian hamster. One group (long photoperiod) was maintained on a light:dark cycle of 14:10, and another group (short photoperiod) on a cycle of 10:14. Five other groups were maintained on a cycle of 10:14 but with a one hour pulse of equally intense illumination in the middle of the dark period with UV, blue, green, yellow or red light. Animals exposed to a long photoperiod or UV, blue or green light pulses had significantly greater testis weights--up to eightfold greater than those in the yellow or red or short photoperiod groups. Organ protein content closely paralleled organ weight, but the protein/wet weight ratio was consistently higher in the large organ groups. K-pNPPase and Mg-pNPPase activities were significantly higher in the large organ groups, even when expressed per mg protein. Therefore, at a balanced irradiance of 0.2uW/cm2, light wavelength exerts a profound effect on testicular weight, protein content, and K-pNPPase and Mg-pNPPase activities. Testicular involution is a process that is selective with regard to protein biosynthesis.     

Effects of various LED light wavelengths and light intensity supply strategies on synthetic high-strength wastewater purification by Chlorella vulgaris

Chemical fertilizer agricultural wastewater is a typical high-strength wastewater that has dramatically triggered numerous environmental problems in China. The Chlorella vulgaris microalgae biological wastewater treatment system used in this study can effectively decontaminate the high-strength carbon and nitrogen wastewater under an optimum light wavelength and light intensity supply strategy. The descending order of both the dry weight for C. vulgaris reproduction and wastewater nutrient removal efficiency is red > white > yellow > purple > blue > green, which indicates that red light is the optimum light wavelength. Furthermore, rather than constant light, optimal light intensity is used for the incremental light intensity strategy. The phases for the optimal light intensity supply strategy are as follows: Phase 1 from 0 to 48 h at 800 μmol m^?2 s^?1; Phase 2 from 48 to 96 h at 1,200 μmol m^?2 s^?1; and Phase 3 from 96 to 144 h at 1,600 μmol m^?2 s^?1. Additionally, the optimal cultivation time is 144 h.     

Unit responses of the cat suprasylvian gyrus to flashes of different wavelengths

Unit responses in the suprasylvian gyrus of the cat to flashes of different wavelengths were studied. Especially in the Clare-Bishop region, about 80% of suprasylvian neurons were found to be color-specific. Four classes of neurons responding differently to different regions of the spectrum were distinguished. The possible principle of coding of information on stimulus color by neurons of the suprasylvian areas is discussed.I. S. Beritashvili Institute of Physiology, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Neirofiziologiya, Vol. 11, No. 1, pp. 11–17, January–February, 1979.     

Transformation of soil invertebrate complex after surface fires of different intensity

The effect of surface fires of different intensity on soil invertebrates was evaluated in central taiga Scotch pine forests in the Yenisey Region of Siberia. In the period of 4–5 years, the abundance and ecological and trophic structure of sandy podzol population was almost completely restored after surface fires of medium and low intensity. The recovery process was decelerated after high intensity fires.     

Regulation of CO2-fixation in Chlorella by light of varied wavelengths and intensities

1) The wavelength effects on ¹⁴CO₂-fixation by Chlorella cellswere studied, using monochromatic light of different light intensities. 2) Blue light (453 mµ) stimulated the incorporation of¹⁴C into aspartate, glutamate and malate. Red light (679 mµ),on the other hand, stimulated its incorporation into P-esters,free sugars and insoluble material. 3) The blue light effect was observed in the presence of CMUat concentrations completely suppressing ordinary photosyntheticCO₂-fixation. 4) The blue light effect in the presence of CMU was inducedat very low intensities. At 453 mµ, 300 erg cm^–2sec^–1 was sufficient for complete saturation. 5) Time courses of ¹⁴C-incorporation into individual compoundswere investigated. Irrespective of the wavelength of the illuminatinglight, the first stable CO₂-fixation product formed under weaklight (400–500 erg cm^–2 sec^–1) was citrulline.At higher light intensities (4,000–7,000 erg cm^–2sec^–1), PGA was the first stable CO₂-fixation product.The incorporation of ¹⁴C into citrulline was not inhibited byCMU. 6) Experimental results indicate that both blue light-inducedincorporation of ¹⁴C into amino and organic acids and the incorporationof ¹⁴C into citrulline induced by low intensity light are operatedby a mechanism(s) independent of ordinary photosynthetic CO₂-fixation.Possible effects of light regulating the carbon metabolism inalgal cells are discussed. (Received July 24, 1969; )     

Spectral shifting of UV-A wavelengths to blue light for enhancing growth rate of cyanobacteria

This study investigates the modification of UV-A radiation for enhancing the growth rate of Synechococcus species in a simulated photobioreactor made of UV-stabilized polycarbonate (PC) plates. Uvitex OB as was dissolved in a poly(methyl methacrylate) (PMMA)-based resin and the mixture was applied as a coating to shift the UV-A radiation to photosynthetically active radiation (PAR). The feasibility of applying the Uvitex OB in a PMMA-based resin, which was used as fluorescent layer to shift UV-A to PAR range, was explored. For this purpose, a variety of concentrations of Uvitex OB in resin were prepared and coated on PC sheets which were placed between the radiation source and the culture flask. Compared to the uncoated PC sheet, the PC panels coated with a few number of the wavelength shifter layer caused an approximately 4-fold increase in cell number during the same culture period.     

细菌生理特性快速检测试剂盒研制

选取各代谢途径中利用某些特定碳源,如蔗糖、葡萄糖、甘露醇等95种碳源作为测试碳源,分别加入96孔酶标板中.选用指示剂噻唑兰(MTT)来鉴定细菌利用特征碳源情况.同时选取不同种类和不同浓度的抗生素,不同起始pH、不同NaCl浓度加入96孔酶标板中,测定细胞是否生长,可以快速地获得该菌的抗生素耐受性谱.试验还从指示剂浓度、培养基的固化、接菌浓度、观察时间等方面对试剂盒进行优化,得到一种最佳的试剂盒鉴定系统BiobiqA(碳源利用谱)和BiobiqB(生理抗性谱).用模式菌株对试剂盒进行测试和验证,结果表明,试剂盒具有操作简便、结果准确、节省成本、节约时间等优点,可以进行细菌生理特性的快速检测.     

不同强度的连续触摸式机械刺激对水稻生理特性的影响

激能降低水稻叶片的质膜透性,但随着处理时间的延长以及刺激强度的增加,质膜透性呈上升趋势;各强度的机械刺激处理均能提高水稻叶绿素a含量,并不同程度地降低叶绿素b含量;轻度机械刺激提高了水稻叶片的过氧化物酶(POD)、超氧化物歧化酶(SOD)和多酚氧化酶(PPO)活性;随着处理时间的延长,各强度的机械刺激处理均能降低叶片吲哚乙酸(IAA)含量,提高脱落酸(ABA)含量及水稻的根系活力。结果表明,机械刺激可能是引起水稻生理特性及形态发生变化的重要因素之一。这些结论可为深入研究鸭稻共作系统中鸭子机械刺激对水稻生长性状的影响及作用机制提供理论依据。