scholarly journals Turning defence into offence? Intrusion of cladoceran brood chambers by a green alga leads to reproductive failure

2020 ◽  
Vol 7 (9) ◽  
pp. 200249
Author(s):  
Dania Albini ◽  
Mike S. Fowler ◽  
Carole Llewellyn ◽  
Kam W. Tang

Microalgae are the foundation of aquatic food webs. Their ability to defend against grazers is paramount to their survival, and modulates their ecological functions. Here, we report a novel anti-grazer strategy in the common green alga Chlorella vulgaris against two grazers, Daphnia magna and Simocephalus sp. The algal cells entered the brood chamber of both grazers, presumably using the brood current generated by the grazer's abdominal appendages. Once inside, the alga densely colonized the eggs, significantly reducing reproductive success. The effect was apparent under continuous light or higher light intensity. The algal cells remained viable following removal from the brood chamber, continuing to grow when inoculated in fresh medium. No brood chamber colonization was found when the grazers were fed the reference diet Raphidocelis subcapitata under the same experimental conditions, despite the fact that both algal species were readily ingested by the grazers and were small enough to enter their brood chambers. These observations suggest that C. vulgaris can directly inflict harm on the grazers' reproductive structure. There is no known prior example of brood chamber colonization by a microalgal prey; our results point to a new type of grazer–algae interaction in the plankton that fundamentally differs from other antagonistic ecological interactions.

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 907-912
Author(s):  
Deepika Masurkar ◽  
Priyanka Jaiswal

Recently at the end of 2019, a new disease was found in Wuhan, China. This disease was diagnosed to be caused by a new type of coronavirus and affected almost the whole world. Chinese researchers named this novel virus as 2019-nCov or Wuhan-coronavirus. However, to avoid misunderstanding the World Health Organization noises it as COVID-19 virus when interacting with the media COVID-19 is new globally as well as in India. This has disturbed peoples mind. There are various rumours about the coronavirus in Indian society which causes panic in peoples mind. It is the need of society to know myths and facts about coronavirus to reduce the panic and take the proper precautionary actions for our safety against the coronavirus. Thus this article aims to bust myths and present the facts to the common people. We need to verify myths spreading through social media and keep our self-ready with facts so that we can protect our self in a better way. People must prevent COVID 19 at a personal level. Appropriate action in individual communities and countries can benefit the entire world.


Author(s):  
Zhang Hong ◽  
Wei-qing Cao ◽  
Ting Li Yang ◽  
Jin Kui Chu

Abstract This paper is the second of a series of two papers which designed a new type of load balancing mechanisms for planetary gearings with arbitrary number of planets. In this paper the common expression of the non-uniform load share factor was deduced, and a function parameter:force-arm factor and their solution was given. That makes it possible that the dimensions and the ability of load equilibrium of Multi-Link Load Balancing Mechanisms can be determined. The criteria of optimum load balancing Mechanisms selection were set up with consider of the effects of turning pair clearances, and optimum mechanisms were selected among the 15 candidates obtained in Part 1. Finally, it was demonstrated that the optimum multi-link load balancing mechanisms for arbitrary number of planets had the similar topological structures and same function and performence of load equilibrium.


2014 ◽  
Vol 496-500 ◽  
pp. 1044-1047 ◽  
Author(s):  
Jia Xiong Zhu ◽  
Qiang Tong

In this paper, based on the principle of induction heating and eddy current fields working, the equivalent circuit model of induction cooker heating was proposed and analyzed. By using the finite element numerical analysis software, the optimization design and model simulations of induction cooker were implemented. Finally, a new design of induction cooker with the uniform heating-coil was proposed, and the magnetic circuit modeling and simulation of new type induction cooker heating was carried out, the eddy current loss density distribution in the common wire coil and the improved wire coil was separately calculated and compared. The results shown the new wire coil had higher energy efficiency and more uniform heating characteristics, which provided a reference for the future optimization design and development of induction cooker.


2007 ◽  
Vol 34 (7) ◽  
pp. 581 ◽  
Author(s):  
Ko Sato ◽  
Hiroaki Ohsato ◽  
Shunsuke Izumi ◽  
Saori Miyazaki ◽  
Hans J. Bohnert ◽  
...  

The common ice plant, Mesembryanthemum crystallinum L., is a eu-halophytic model species with an environmental stress-initiated switch from C3 photosynthesis to crassulacean acid metabolism (CAM). Phosphoenolpyruvate carboxylase activity in 6-week-old plants exposed to salt stress for 5 days was ~15-fold higher than before stress, indicating the salinity-dependent induction of the C3 to CAM transition. Five plant protein phosphatase type 2C (PP2C) genes were cloned, representative of five of the 10 plant PP2C sub-families. We measured mRNA levels of these PP2Cs and of myo-inositol 1-phosphate synthase (Inps1) in 6-week-old plants before (C3) and after (CAM) salt stress. Remarkably, four PP2C genes and Inps1 were expressed with a diurnal fluctuation in plants in C3 mode. After salt-induced CAM induction, the six genes were expressed with more prominent fluctuations than before stress, suggesting that these PP2C genes may be involved in the diurnal regulation of protein phosphorylation in CAM. Under continuous light treatment the expression of two PP2C genes continued to fluctuate, indicating that their expression is controlled by circadian rhythm.


1973 ◽  
Vol 71 (1-2) ◽  
pp. 1-8 ◽  
Author(s):  
Sylvio Celso Goncalves da Costa ◽  
Samuel B. Pessoa ◽  
Neize de Moura Pereira ◽  
Tania Colombo

The main object of the present paper is to furnish a brief account to the knowledgement of Protozoa parasitic in common Brazilian frog of the genus Leptodactylus for general students in Zoology and for investigators that use this frog as a laboratory animal. Hepatozoon leptodactyli (Haemogregarina leptodactyli) was found in two species of frogs - Leptodactylus ocellatus and L. pentadactylus - in which develop schizogony whereas sporogony occurs in the leech Haementeria lutzi as was obtainded in experimental conditions. Intracellular forms have been found in peripheral circulation, chiefly in erythrocytes, but we have found them in leukocytes too. Tissue stages were found in frog, liver, lungs, spleen, gut, brain and heart. The occurence of hemogregarine in the Central Nervous System was recorded by Costa & al,(13) and Ball (2). Some cytochemical methods were employed in attempt to differentiate gametocytes from trophozoites in the peripheral blood and to characterize the cystic membrane as well. The speorogonic cycle was developed in only one specie of leech. A brief description of the parasite is given.


2020 ◽  
Vol 28 (4) ◽  
pp. 384-389
Author(s):  
A. P. Pokhylenko ◽  
O. O. Didur ◽  
Y. L. Kulbachko ◽  
L. P. Bandura ◽  
S. A. Chernykh

The paper presents a study about the influence of two saprophage groups (Isopoda, Diplopoda) on leaf litter decomposition under different levels of humidification and chemical stress. Because of their worldwide distribution, we focused on the common pillbug Armadillidium vulgare (Latreille, 1804) (Isopoda, Armadillidiidae), and the common millipede species Rossiulus kessleri (Lohmander, 1927) (Julida, Julidae). The function of environment creation by the given saprophages, as destructors of dead plant matter, supporting such ecosystem services as soil fertility improvement and nutrients’ turnover, is highlighted. To conduct the experiment, the animals were collected manually and using pitfall trapping. In order to bring the experimental conditions closer to the natural, the individuals were not sexed. The maximum consumption of leaf litter by woodlice was recorded in the conditions with adequate moisture (0.5 mL of distilled water per box) and amounted to 2.52 mg/10 individuals per day, which exceeds its consumption with low and increased moisture, respectively, by 1.82 and 1.24 times. As for the effect of interaction, the consumption of maple litter with optimal moisture (4.77 mg/10 individuals per day) was the greatest. The largest absolute difference between broad-leaved tree species in the average weight of leaf litter consumed by woodlice was between maple leaf litter and oak leaf litter, the minimum – between robinia leaf litter and oak leaf litter. According to the results of the obtained data (Diplopoda), it can be stated that there is a statistically significant effect of chemical stress and discrepancy of the average zinc content in the object of study (in Diplopoda and their faecal pellets). We found that the diet provided did not affect the distribution of zinc in Diplopoda under conditions of chemical stress. According to the results of pairwise comparisons, we determined that the zinc content in the Diplopoda clearly differs for control and almost every concentration of zinc sulfate solution – 0.03 and 0.15 g/L, the samples of which do not form a homogeneous group. The species composition, abundance and distribution in space of soil invertebrates are informative indicators which reflect the ecological state of soils, intensity in development of soil horizons as well as intensity of processes occurring in them.


Author(s):  
W. J. Xie ◽  
L. Zhang ◽  
H. P. Chen

Abstract. GlobeLand30 update data is one of the important products of the Construction Maintenance and Update of Geographic Information Resources Project (hereinafter referred to as the Update Project). It provides important basic information for national geographical conditions monitoring, eco-environmental assessment and global geographic information integrated services. Different from the land cover classification data in National Geoinformation Surveying and Monitoring Project, GlobeLand30 update data is a completely new type of scientific research outcomes with new setup of resolution, its data format and data structure are newly set according to the requirements of the Update Project. Therefore, current inspecting methods are of limitations and incompatibility and cannot be firmly reasonable for inspecting the accuracy of GlobeLand30 update data. Combining with the practice of quality control for the Update Project, this paper proposes a set of methods and processes for the quality inspection of the GlobeLand30 update data. It also summarizes the key points of its inspection and analyses the common errors found in the actual inspection practice of the Update Project from 2017 to 2018. It can provide a certain technical reference for the quality control and quality improvement of GlobeLand30 update data in the Update Project.


2021 ◽  
Vol 10 (2) ◽  
pp. 257-274
Author(s):  
Nofrida Panjaitan ◽  
Joko Adianto

The spread of pneumonia cases caused by a new type of Coronavirus (Novel Coronavirus) SARS Cov-2 was established by WHO called Coronavirus Disease 2019 (COVID-19) on February 2020 and designated as a pandemic on March 11, 2020. However, an interesting phenomenon arises, despite the high number of COVID-19 spread in Jakarta. That is as of April 10, 2020, 50 out of 267 urban villages in Jakarta are declared free of COVID-19 (not infected with the virus) and one of them is the most populous village in Jakarta called the most densely populated urban village in Southeast Asia, namely Kalianyar in Tambora Sub District, West Jakarta.This study aims to find out how does Kalianyar combat the spread of COVID-19, recalling that considering the nature of the virus transmission, Kalianyar has high potential to be a vulnerable zone. The research was conducted through a qualitative analysis on a case study of Kalianyar aiming to examine the deep explanation and understanding of distinctive implementation and to obtain the lesson learned from the implementation of Fournier's idea seeing how the common process occurs. The common process occurring within social organization in Kalianyar shows that there are relational and reciprocal relationships resulting from each activity related to the three axes as suggested by Fournier.


Author(s):  
Hromko T.V.

Purpose. The article considers methodological problems of mono-verbal ideographic dictionary as a separate lexicographic set of dialectal usus, built on the onomasiological principle, on the semantic relations of words from the concept to its lexical counterparts. By typology, ideographic and explanatory dictionaries are complementary, which determines the equipolent connection of the ideographic dictionary with the thesaurus of a separate language system. Methods. The monophonic ideographic dictionary proposed by the author offers a methodology for developing an ideographic dictionary of speech on a purely linguistic basis, in the direction “from the core to the periphery”, because the lexical structure of the idiom, in contrast to the common language, is narrowly accessible for speakers of the literary idiom and widely available for scientific interpretation of the lexicon of speech, and given the completeness of the presentation allows the use of quantitative methods. They ensure the objectivity of the obtained results and significantly reduce the time for their receipt and processing, which in the long run will provide objective results for further qualitative (qualitative) analysis – a monographic description of the language system of speech. Results. Monographic ideographic dictionary is a new type of dictionary – linguistic dialectological ideographic dictionary of scientific and linguodidactical purpose. Methodologically, its conclusion involves the stratification of vocabulary by functional, syntagmatic, paradigmatic and epidigmatic system parameters. Conclusions. Improving the method of parametric analysis for a one-word ideographic dictionary involves in the process of compiling the author of the “Ideographic Dictionary of the dialect of Pishchany Brid village of Dobrovelychkivsky district of Kirovohrad region” conducting various typological studies: continuing to collect natural dialect material, representation of the place of this lexical unit in its structure, etc., as well as ideographic lexicographic parameterization for component analysis of dialectal vocabulary, which will extrapolate the spoken material, and in the future will serve to solve a number of theoretical and practical problems of linguistics, and research will enter the linguistic picture of the world and give objective scientific results.Key words: dialectology, lexicography, monoidiom research, ideographic method, quantitative methods, qualitative analysis of vocabulary. Анотація.Мета. У статті розглядаються методологічні проблеми моноговіркового ідеографічного словника як окремого лексикографічного зводу діалектного узусу, побудованого за ономасіологічним принципом, за смисловими відношеннями слів від поняття до його лексичних відповідників. За типологією ідеографічні й тлумачні словники є взаємодоповню-вальними, що й визначає еквіполентний зв’язок ідеографічного словника з тезаурусом окремої мовної системи. Методи.Пропонований автором моноговірковий ідеографічний словник пропонує методологію розробки ідеографічного словника говірки за суто лінгвістичною основою, у напрямі «від ядра до периферії», оскільки лексичний склад ідіому, на відміну від загальномовного, є вузькодоступним для носіїв літературного ідіому і широкодоступним для наукової інтерпретації лексикону говірки, а з огляду на повноту представлення дозволяє використовувати квантитативні методи. Вони забезпечують об’єктивність отриманих результатів і значно скорочують час на їх отримання і обробку, що у перспективі дасть об’єктивні результати для подальшого квалітативного (якісного) аналізу – монографічного опису мовної системи говірки. Результати. Моноговірковий ідеографічний словник є новим типом словника – лінгвістичним діалектологічним ідеографічним словником наукового та лінгводидактичного призначення. Методологічно його укладання передбачає стратифікацію лексики за функціональним, синтагматичним, парадигматичним й епідигматичним системними параметрами. Висновки. Удосконалення методу параметричного аналізу для моноговіркового ідеографічного словника передбачає у процесі укладан-ня автором «Ідеографічного словника говірки села Піщаний Брід Добровеличківського району Кіровоградської області» проведення різного роду типологічних досліджень: продовження збирання польового діалектного матеріалу, проведення квалітативного аналізу лексики на предмет ядра й периферії мовної системи, наочного представлення того, яке місце посідає така лексична одиниця в його структурі тощо, а також ідеографічної лексикографічної параметризації для проведення компонентного аналізу діалектної лексики, що екстраполюватиме говірковий матеріал, а в перспективі прислужиться для вирішення низки теоретичних і практичних завдань лінгвістики, і проведені за ним дослідження увіллються в мовну картину світу та дадуть об’єктивні наукові результати.Ключові слова: діалектологія, лексикографія, моноговіркові дослідження, ідеографічний метод, квантитативний метод, квалітативний аналіз лексики.


HortScience ◽  
2017 ◽  
Vol 52 (3) ◽  
pp. 436-440 ◽  
Author(s):  
Chandrappa Gangaiah ◽  
Amjad Ahmad ◽  
Hue V. Nguyen ◽  
Koon-Hui Wang ◽  
Theodore J.K. Radovich

The application of locally available invasive algae biomass as a fertilizer for crop production in Hawaii is being investigated as a substitute for imported chemical fertilizers. Three closely related greenhouse trials were conducted to determine if the algae served as a source of potassium (K) on growth, yield, and K mineral nutrition in pak choi (Brassica rapa, Chinensis group). In the first trial, three algal species (Gracilaria salicornia, Kappaphycus alvarezii, and Eucheuma denticulatum) were applied at five rates of K, each to evaluate their effects on growth and K nutrition of pak choi plants. The pak choi was direct seeded into 0.0027-m3 pots containing peatmoss-based growth media. In trial 2, pak choi was grown in peat media at six rates of K provided by algae (E. denticulatum) or by potassium nitrate (KNO3). In trial 3, the six rates of K were provided through algae (K. alvarezii), KNO3, and potassium chloride (KCl) and were compared for growth and K nutrition. Results from the first greenhouse trial showed no significant differences among the three algal species in yield or tissue K content of pak choi. However, plant yield and tissue K concentration were increased with application rates. The maximum yield and tissue K were observed when K was provided within the range of 250–300 kg·ha−1. Similarly, in Expts. 2 and 3, there were no significant differences between commercial K fertilizers and algal K species for yield. Only K rates were significant for yields and tissue K concentrations. It was concluded that K in the invasive algae was similarly available as K in commercial synthetic fertilizers for pak choi growth in terms of yield and tissue K content under our experimental conditions.


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