Variation in lipid reserves of second-stage juveniles of Meloidogyne exigua in a coffee field and its relationship with infectivity

Nematology ◽  
2010 ◽  
Vol 12 (3) ◽  
pp. 365-371 ◽  
Author(s):  
Fernando da Silva Rocha ◽  
Jorge Teodoro de Souza ◽  
Vicente Paulo Campos

AbstractIn this study we assessed the variations in lipid content of second-stage juveniles (J2) of Meloidogyne exigua, recovered from a coffee field, by staining and quantifying the neutral lipids using image analysis. Our results showed that annual variations in J2 stained lipid area correlate with temperature, rainfall and total number of J2 per 100 cm3 of soil. Laboratory and glasshouse experiments showed that decreases in the lipid stained area of J2 of M. exigua led to decreased infectivity and reproduction on tomato. The susceptibility of tomato cvs Kada and Nemadoro to M. exigua varied according to the stained lipid area of the J2 inoculated on roots. Only J2 containing an average of 80% stained lipid area were able to infect cv. Nemadoro, which contains the Mi resistance gene, whereas J2 containing 20% stained lipid area were still able to infect cv. Kada, considered to be highly susceptible. In this study we show for the first time the dynamics of lipid variation in J2 of M. exigua in a coffee field and the dependence of infectivity and parasitism on the resistance level of tomato cultivars and the lipid stained area in J2.

Nematology ◽  
2015 ◽  
Vol 17 (3) ◽  
pp. 345-352 ◽  
Author(s):  
Fernando da Silva Rocha ◽  
Vicente Paulo Campos ◽  
Hugo César Rodrigues Moreira Catão ◽  
Maria de Fátima Silva Muniz ◽  
Nody Civil

We studied the correlations between the processes used to estimate the body lipid of second-stage juveniles (J2) of Meloidogyne exigua and M. incognita, and the infectivity and reproduction of the M. incognita J2. The lipids were quantified by image analysis of the area stained red with Oil Red O dye and by the dark area of the non-stained J2. The content of neutral lipids of stained J2 of M. exigua and M. incognita correlated positively to the lipid index, body mass lipid and the dark area of J2. The period of incubation of J2 decreased the neutral lipids content and correlated significantly with the reductions of infectivity and reproduction. The period of 6 days incubation of M. incognita resulted in losses of more than 50% of the neutral lipid content, representing the threshold period for infectivity on tomato, whereas, for reproduction, the threshold was 3 days incubation.


Author(s):  
Т.А. Богумил

В статье предлагается концепция жизни и творческого роста В.М. Шукшина сквозь призму тезаурусного и кластерного подходов. Объяснительными «персональными моделями» для интерпретации биографического текста писателя являются кластеры Мартина Идена, Гамлета и Степана Разина. Ранее биографы и литературоведы указывали на важность этих персон для Шукшина, но разрозненно. Впервые предпринята попытка свести указанные персональные модели воедино, в целостный сюжет становления писателя в пространстве культуры. На разных этапах эволюции автора доминирует одна из указанных моделей, последовательно сменяя друг друга, но не вытесняя, а «внахлест». Ранний этап творчества, ориентированный на стратегию Мартина Идена, является попыткой «вписаться» в наличный культурный мейнстрим. Выражено это в следовании поэтике соцреализма. Второй этап подспудно начинается с реабилитации отца Шукшина в 1956 года, когда актуализируется «гамлетовский комплекс», проявляющийся в чувстве вины перед отцом, через стратегию утаивания подлинного «я», мотивы чудаковатости. Третий этап связан с личностью реального исторического лица, Степана Разина, и выражается в открытом протесте против власти. Все важные для В.М. Шукшина поведенческие модели объединены мотивом одинокого противостояния враждебному социуму и имеют трагический финал, что обусловило ранний уход писателя и порождение мифов о насильственном характере его смерти. В.М. Шукшин одновременно был фигурой неординарной и типичной, что позволило его биографии стать «персональной моделью» для последующих авторов, выходцев из сельской глубинки. The article proposes the concept of life and creative growth of V.M. Shukshin through the prism of the thesaurus and cluster approach. The explanatory "personal models" for interpreting the biographical text of the writer are clusters of Martin Eden, Hamlet and Stepan Razin. Earlier, biographers and literary critics pointed out the importance of these people for Shukshin, but it was scattered. For the first time, an attempt was made to bring these personal models together into an integral plot of the formation of the writer in the space of culture. At different stages of the writer’s evolution, one of these models dominates, successively replacing each other, but not crowding out, but “overlapping”. The early stage of creativity, focused on Martin Eden’s strategy, is an attempt to “fit in” the current cultural mainstream. This is expressed in following the poetics of socialist realism. The second stage implicitly begins with the rehabilitation of Shukshin’s father in 1956, when the “Hamletian complex” is actualized. It is manifested in a sense of guilt towards his father, the strategy of concealing the true “I”, eccentricities. The third stage is connected with the personality of a real historical person, Stepan Razin, and is expressed in an open protest against the authorities. All important for V.M. Shukshin's behavioral models are united by the motive of a lonely confrontation with a hostile society and have a tragic ending, which led to the early departure of the writer and the generation of myths about the violent nature of his death. V.M. Shukshin was an extraordinary and typical figure at the same time. That allowed his biography to become a “personal model” for subsequent authors who came from the rural outback.


2021 ◽  
Vol 36 (5) ◽  
pp. 596-607
Author(s):  
O. Ekşi

Abstract The aim of this study is to determine the thickness distribution of a food package using a non-destructive method. Initially, thickness measurements were carried out using an experimental procedure for thermoformed samples that were used for food packaging. Additionally, in this study, image analysis was used for the first time to determine the thickness distribution of the thermoformed products non-destructively. Image analysis software was employed for the estimation of thickness distribution. Measured thickness results were compared to those estimated using image analysis. Based on the results of the current study, image analysis may be an alternative method for non-destructive testing of thermoformed food packages even in a mass production line. Image analysis can be used to determine not only thickness distribution but also the weakest regions in a food package.


Author(s):  
Wei Liu ◽  
Yunbo Yuan ◽  
Tao He ◽  
Donghua Wang

Considering the effect of teeth surface sliding friction, free vibration of two-stage planetary gears (TPG) is studied theoretically for the first time. The lateral-torsional coupling dynamic model and equation are established with three degrees of freedom: two translations and one rotation. The change rule of natural frequency is discussed with the case of first stage planetary gear’s number 4 and second stage planetary gear’s number 3, 4 and 5. Afterwards three vibration modes are summarized by calculating the free vibration. In order to understand the behavior of friction, the effect of friction on natural frequencies is analyzed for the case of considering friction and not considering friction. Furthermore, the ‘self-coupling’ phenomenon is obtained from the vibration of center component of TPG Meanwhile, the ‘mutual coupling’ is obtained between the first-stage planetary gear (FPG) and the second-stage planetary gear (SPG).


1985 ◽  
Vol 38 (6) ◽  
pp. 775
Author(s):  
W Livingston

R. G. Giovanelli was appointed as a Visiting Scientist at Kitt Peak National Observatory for six months in both 1975 and 1979, and then for an entire year in 1981. These times proved fruitful to him as well as to the Observatory. The Vacuum Telescope and its 512-channel magnetograph had been completed and were operational. Complementing this was a new powerful 2D image analysis machine called the Interactive Picture Processing System (IPPS). For the first time, solar surface features could be quantitatively observed, usually to a seeing limited resolution composed of arcsec pixels, and then readily analysed as pictures. As is often the case, those who built the instruments remained preoccupied with their perfection, and it fell to Giovanelli to put these new tools to effective use. He did this in a series of research efforts reviewed in the present paper. Happily, he drew many of us in Tucson into his projects, injecting us with enthusiasm and enlarging our knowledge of solar physics in the process.


1972 ◽  
Vol 46 (2) ◽  
pp. 125-137 ◽  
Author(s):  
R. C. Chhabra ◽  
Kunwar Suresh Singh

The development of the preinfective stages of S. lupi has been described and illustrated and the details of morphology given for the first time.The sex of the first stage juveniles can be distinguished by locating the position of the genital primordium. On an average, the first stage juveniles measure 0·39 mm. in length and 0·036 mm. in breadth, early second stage 0·78 and 0·044 mm. and the advanced second stage 1·40 mm. and 0·63 mm. respectively. The second stage juveniles obtained from beetles were not infective to dogs.


1989 ◽  
Vol 44 (7-8) ◽  
pp. 597-608 ◽  
Author(s):  
Helen J. Stavrakakis ◽  
Sofia K. Mastronicolis

The total lipids of the commercial land snail Eobania vermiculata (Gastropoda, Pulm onata, Stylom m atophora) are found to constitute a small percentage (0.8% ) of the wet tissue, which is comparable to that reported for other gastropods. Polar lipid components comprise 61.4% of the total lipids. The individual lipid classes obtained by column chromatographic fractionation were purified by preparative TLC or by column chromatography and their structure was confirmed by a combination of chromatographic and analytical determinations before and after mild alkaline hydrolysis and/or (dry) acid methanolysis and by IR analysis. Neutral lipids represent 36.4% of total lipids, containing cholesterol, cholesterol esters and triglycerides as their major components (26.2% , 29.1% and 25.5% respectively). They contain also a significant amount (14%) of free glyceryl ethers, which are found in a mollusc for the first time. The overall composition of the polar lipids (mol/100 mol lipid-P) was found as follows: Cardiolipin, 2.9; phosphatidylethanolamine, 24.9 (of which 19.8% plasmalogen analog); phosphatidylcholine, 49.2 (of which 45.6% glycerylether analog); ceramide aminoethylphosphonate, 7.5 plus 0.01 (another three minor species); diglyceride-am noethylphosphonate, 6.3; Sphingoethanolamine 1.65 (for the first time found and structurally studied in a land gastropod); and phosphatidic acid 1.1. Unsaturated fatty acyl groups represent about 72.6 and 44.1 respectively in phosphatidylethanolamine and phosphatidylcholine. A significant amount (70.5% ) of unsaturated fatty acids is concentrated in neutral lipids. The C16:0 alk-1-enyl chain was found to predominate (55.6% ) in the side chains of ethanolamine plasmalogen. Batyl alcohol was found as the main glycerylether bound to choline phosphate (97.5% ). Saturated fatty acyl groups with 16 carbon atoms were main components (54%) of the major ceramide aminoethylphosphonate species.


2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Silvia Donzella ◽  
Daniela Cucchetti ◽  
Claudia Capusoni ◽  
Aurora Rizzi ◽  
Silvia Galafassi ◽  
...  

Abstract Background Oleaginous yeasts are able to accumulate very high levels of neutral lipids especially under condition of excess of carbon and nitrogen limitation (medium with high C/N ratio). This makes necessary the use of two-steps processes in order to achieve high level of biomass and lipid. To simplify the process, the decoupling of lipid synthesis from nitrogen starvation, by establishing a cytosolic acetyl-CoA formation pathway alternative to the one catalysed by ATP-citrate lyase, can be useful. Results In this work, we introduced a new cytoplasmic route for acetyl-CoA (AcCoA) formation in Rhodosporidium azoricum by overexpressing genes encoding for homologous phosphoketolase (Xfpk) and heterologous phosphotransacetylase (Pta). The engineered strain PTAPK4 exhibits higher lipid content and produces higher lipid concentration than the wild type strain when it was cultivated in media containing different C/N ratios. In a bioreactor process performed on glucose/xylose mixture, to simulate an industrial process for lipid production from lignocellulosic materials, we obtained an increase of 89% in final lipid concentration by the engineered strain in comparison to the wild type. This indicates that the transformed strain can produce higher cellular biomass with a high lipid content than the wild type. The transformed strain furthermore evidenced the advantage over the wild type in performing this process, being the lipid yields 0.13 and 0.05, respectively. Conclusion Our results show that the overexpression of homologous Xfpk and heterologous Pta activities in R. azoricum creates a new cytosolic AcCoA supply that decouples lipid production from nitrogen starvation. This metabolic modification allows improving lipid production in cultural conditions that can be suitable for the development of industrial bioprocesses using lignocellulosic hydrolysates.


Nematology ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 111-121
Author(s):  
Luma A. Pedroso ◽  
Vicente P. Campos ◽  
Aline F. Barros ◽  
Julio C.P. Silva ◽  
Gustavo M. Assis ◽  
...  

Summary The cyst nematode, Heterodera glycines, is a major pathogen of soybean in tropical regions, which demands novel sustainable management practices. In this work, the use of ethanol against H. glycines was evaluated as both a solution and a fumigant. On second-stage juveniles (J2) of H. glycines, ethanol at low concentration was more effective by direct dipping than by only fumigating the J2. Hatching was significantly reduced by direct dipping in ethanol solutions. Fumigation of H. glycines-infested soil with ethanol reduced infectivity by almost 100% and the number of eggs by about 67% at ethanol concentrations of 48% and 72%, respectively. Only the ethanol at 48% concentration significantly reduced the J2 lipid content, while J2 infectivity and the number of eggs were reduced by dipping at 6% ethanol. The J2 were internally altered by the ethanol solutions. Therefore, ethanol is toxic to H. glycines at low concentrations and affects its pathogenic behaviour rather than simply reducing the lipids.


Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3564 ◽  
Author(s):  
Krzysztof Skrzypkowski

The article presents methods of securing mining excavations using wooden cribs. For the underground room and pillar method used to excavate zinc and lead ore body in the Olkusz-Pomorzany mine in Poland, model tests for the replacement of rock pillars by wooden cribs are presented. In the first stage of research, the results of laboratory strength tests carried out on models of four-point, six-point and eight-point cribs made of wooden beech beams at a 1:28 scale arranged horizontally were determined. For the first time, a concave round notch connection was used to connect the beams of the wooden cribs. The maximal capacity of cribs consisting only of beams and filled with waste rocks taken from underground mining excavations was determined. In addition, the vertical deformations of the cribs at maximal loading force and their specific deformations are presented. Additionally, on the basis of load-displacement characteristics, the range in variability of the stiffness of empty cribs and those filled with waste rocks was calculated as a function of their compressibility. In the second stage of research, the room and pillar method was designed in the Phase2 numerical program. The aim of the study was to determine the stresses in the inter-room pillars. Based on the results of laboratory and numerical tests, a factor of safety was determined, indicating that it is possible to reduce mining losses while maintaining the safe exploitation conditions of the ore body.


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