Journal articles: 'Roses Propagation'

1

Hoşafçı, H., N. Arslan, and E. O. Sarıhan. "PROPAGATION OF DOG ROSES (ROSA CANINA L.) BY SEED." Acta Horticulturae, no. 690 (September 2005): 159–64. http://dx.doi.org/10.17660/actahortic.2005.690.24.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Wisniewska-Grzeszkiewicz, H., and M. Podwyszynska. "PROPAGATION OF GROUND COVER ROSES BY STEM CUTTINGS AND TISSUE CULTURE." Acta Horticulturae, no. 547 (February 2001): 371–76. http://dx.doi.org/10.17660/actahortic.2001.547.45.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Rosu, A., O. Mitica, and S. M. Ariton. "Biotechnological Methods for the Enhancement of the Propagation Rate in Roses." Biotechnology & Biotechnological Equipment 14, no. 2 (January 2000): 32–36. http://dx.doi.org/10.1080/13102818.2000.10819084.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Markovic, Marija, Danijela Djunisijevic-Bojovic, Dragana Skocajic, Marijana Milutinovic, and Katarina Buvac. "Optimizing the micropropagation protocol for Rosa canina L. elite genotype propagation in the Belgrade area." Bulletin of the Faculty of Forestry, no. 123 (2021): 87–96. http://dx.doi.org/10.2298/gsf2123087m.

Full text

Abstract:

Rosa canina L. (dog rose) is an important ornamental, edible and medicinal plant. It has been used as a rootstock for ornamental roses, grown in plantations for fruit harvesting and it is suitable for revegetation of abandoned mine lands. The propagation of native genotypes that are well adapted to local conditions can provide planting material for both revegetation and plantation purpose. Micropropagation is the most suitable method for a rapid vegatative propagation of selected wild genotypes, but an increased presence of pathogens as well as higher contamination rate during culture establishment were expected. An occurrence of a specific Fe-chlorosis during in vitro propagation of roses is also possible. Therefore, the optimal period and disinfection protocol for establishing sterile in vitro culture of selected genotypes of dog rose was investigated, as well as an effect of increasing the FeEDTA concentration in the MS medium during multiplication phase. The obtained results showed that the optimal time for taking initial explants corresponds to optimal time for taking green cuttings in traditional vegetative propagation by softwood cuttings, and the best results were achieved using shoots collected in the first week of May, when the flowers were open. The iron chelate concentration in the medium affected the mean number of shoots, and doubling of its concentration resulted in a considerably higher number of shoots per explant.

APA, Harvard, Vancouver, ISO, and other styles

5

Klimenko, Z. K., S. A. Plugatar, V. K. Zykova, and I. N. Kravchenko. "Using of tea-hybrid roses from the Nikita Botanical Gardens’ collection in the floriculture of the Southern Coast of the Crimea." Plant Biology and Horticulture: theory, innovation, no. 154 (October 21, 2020): 65–77. http://dx.doi.org/10.36305/2712-7788-2020-1-154-65-77.

Full text

Abstract:

The article presents the results of a long-term research on the introduction study and evaluation of cultivars of tea-hybrid roses introduced and selected by the Nikitsky Botanical Gardens to determine the possibilities of their use in floriculture of the Southern Coast of the Crimea. The research was conducted in the period from 1955 to 2014. The material for the study was 679 cultivars of garden roses from the tea-hybrid garden group of the collection of the Nikitsky Botanical Gardens. As a result of a comprehensive study, 400 cultivars are recommended for use in the floriculture of the Crimea. The main options for this use becomes the growing of tea-hybrid roses in the open ground for gardening purposes in bush and tree-shaped forms, as well as the growing cultivars for cutting in both open and protected ground. The biological features of the cultivars, which determine the possibility of different types of the use and the cultivars, that have these features were identified: 400 cultivars were recommended for use in landscaping in bush form, 45 cultivars - also in tree-shaped form, 226 cultivars are promising for cutting in the open ground and 107 cultivars - for forcing and cutting in greenhouses. The main methods of propagation of cultivars of tea-hybrid roses under the conditions of the Southern Coast of the Crimea are budding and rooting of green and hardwood cuttings. The optimal timing for propagation by each of these methods is indicated. The best rootstocks for budding were identified, depending on the type of their use in floriculture.

APA, Harvard, Vancouver, ISO, and other styles

6

Byrne, David H., Patricia Klein, Muqing Yan, Ellen Young, Jeekin Lau, Kevin Ong, Madalyn Shires, et al. "Challenges of Breeding Rose Rosette–resistant Roses." HortScience 53, no. 5 (May 2018): 604–8. http://dx.doi.org/10.21273/hortsci12553-17.

Full text

Abstract:

Rose rosette disease (RRD) whose causal agent, the Emaravirus Rose rosette virus (RRV), was only recently identified has caused widespread death of roses in the midwestern and eastern sections of the United States. A national research team is working on the detection and best management practices for this highly damaging disease. Unfortunately, little is known about the host plant resistance to either the causal viral agent or its vector, the eriophyid mite Phyllocoptes fructiphilus. Thus far, the only confirmed resistance is among Rosa species. Of the over 600 rose cultivars observed, only 7% have not exhibited symptoms of RRD. Replicated trials are in progress to confirm resistance and/or susceptibility of ≈300 rose accessions in Tennessee and Delaware. Rose is a multispecies cultivated complex that consists of diploid, triploid, and tetraploid cultivars. The basic breeding cycle is 4 years with a 3-year commercial trial coupled with mass propagation before release. Thus, if only one breeding cycle is needed, a new cultivar could be produced in 7 years. Unfortunately, for the introgression of a new trait such as disease resistance from a related species into the commercial rose germplasm, multiple generations are required which can easily take two decades from the first cross to cultivar release. Research is ongoing to develop a rapid selection procedure for resistance to RRD with the aid of molecular markers associated with the resistance. Such an approach has the potential of reducing the breeding cycle time by 50% and increasing the efficiency of seedling and parental selection manifold, leading to commercially acceptable rose cultivars with high RRD resistance in less time and with less expense.

APA, Harvard, Vancouver, ISO, and other styles

7

Mederos, S., and M. J. Rodríguez Enríquez. "IN VITRO PROPAGATION OF "GOLDEN TIMES" ROSES. FACTORS AFFECTING SHOOT TIPS AND AXILLARY BUDS GROWTH AND MORPHOGENESIS." Acta Horticulturae, no. 212 (September 1987): 619–24. http://dx.doi.org/10.17660/actahortic.1987.212.103.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

MONDER, Marta Joanna, Konrad WOLIŃSKI, Maciej NIEDZIELSKI, and Andrzej PACHOLCZAK. "The Impact of Seasonal Changes in Plant Tissue on Rhizogenesis of Stem Cuttings of Once Blooming Roses." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 44, no. 1 (June 14, 2016): 92–99. http://dx.doi.org/10.15835/nbha44110244.

Full text

Abstract:

The majority of old and long-to-root roses are enough frost resistant to grow on their own roots in moderate and coolclimates. The most often used method of rose propagation are single node stem cuttings derived from blooming shoots. Thelong duration of rhizogenesis exposes cuttings to stress conditions and precocious ageing processes, which result in a lowrooting percentage. It was hypothesized that in the short season of flowering the amount of nutrients in shoots of stock plantschanges, thus affecting the process of rhizogenesis, as well as a condition of rooted cuttings, which may be estimated by thecontents of the biologically active components. The shoots of four rose cultivars were cut in four phenological stages: flowerbuds closed, flowers opened, just after petal shedding and 7-14 days after petal fall. The rooting percentage were counted after10 weeks of rooting. The evaluation of plant material were carried out before and after rooting, including: soluble proteins,chlorophyll a and b, carotenoids, polyphenolic acids, reducing and total soluble carbohydrates. The research revealedvariability, characteristic for each examined cultivar, in the contents of the biologically active compounds, both before and afterrooting, in cuttings harvested from stock plants in successive phases of development. Decrease in pigment contents in leaves ofrooted cuttings may suggest a progressing senescence, both during propagation and later in a vegetative season. The cuttings of‘Mousseuse Rouge’ rooted similarly when harvested in each of the phenological phases (53.8-67.5%). For other cultivars thehighest rooting percentage was obtained for cuttings harvested from shoots with closed flower buds: (‘Hurdals’ 47.5%,‘Maiden’s Blush’ 55.0%, ‘Semiplena’ 67.5%). In these cultivars a relationship between rooting percentage and changes in thecontents of pigments, sugars or/and polyphenolic acids in successive phenological phases was shown.

APA, Harvard, Vancouver, ISO, and other styles

9

Maria, Bala, Rusimovici Raico, Tota Cristina Elena, Petrescu Irina, Berar Cristian, and Silivasan Marius. "Research on the behavior of variety of Roses hybrid Polyantha on propagation by cuttings under a modern greenhouses." Journal of Biotechnology 185 (September 2014): S114. http://dx.doi.org/10.1016/j.jbiotec.2014.07.389.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Park, Su Min, Eun Jeong Won, Yoo Gyeong Park, and Byoung Ryong Jeong. "Effects of node position, number of leaflets left, and light intensity during cutting propagation on rooting and subsequent growth of domestic roses." Horticulture, Environment, and Biotechnology 52, no. 4 (August 2011): 339–43. http://dx.doi.org/10.1007/s13580-011-0163-z.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

MALIK, Małgorzata, Marzena WARCHOŁ, and Bożena PAWŁOWSKA. "Liquid Culture Systems Affect Morphological and Biochemical Parameters during Rosa canina Plantlets In Vitro Production." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 46, no. 1 (January 1, 2018): 58–64. http://dx.doi.org/10.15835/nbha46110880.

Full text

Abstract:

Wild roses are an important group of plants used as decorative shrubs and cut flowers. They are also a row material for pharmaceutical, cosmetic and food industries. For rose in vitro propagation, solid media are commonly used. Up till now there is a few reports confirming the beneficial effect of liquid media on Rosa shoot growth and multiplication. The aim of the study was to investigate different culture systems, temporary immersion system (TIS) (immersion frequencies of 15 min every 6, 8 and 12 h), rotary shaker (RS) and stationary liquid (SL) for propagation of R. canina and compare with solid medium culture. Shoot tips and stem explants were grown on basic Murashige and Skoog medium with 20 mg dm-3 Fe EDDHA, 1 µM BA, 1.5 µM GA3 and 3% sucrose for six weeks. Liquid cultures stimulated biomass growth. The highest biomass growth in RS cultures were observed however, RS reduced the shoot dry mass content. TIS cultures immersed every 6 and 8 h increased dry mass content. In TIS and on solid medium shoot multiplication was 1.5-2 times better than in other systems and stem explants were more efficient. Solid medium improved the content of chlorophyll a, b, a+b and carotenoids. Higher contents of photosynthetic pigments were determined in shoot tips than stem explants. TIS-derived plantlets accumulated the largest amount of phenolic compounds. As the frequency of immersion increases the concentration of these compounds were reduced. In turn, SL cultures favored the accumulation of soluble sugars.

APA, Harvard, Vancouver, ISO, and other styles

12

Churikova, O. A., and A. A. Krinitsina. "Creation and maintanance of in vitro collections of ornamental cultures from the Lomonosov MSU Botanical Garden’s funds." Plant Biology and Horticulture: theory, innovation, no. 156 (December 31, 2020): 55–64. http://dx.doi.org/10.36305/2712-7788-2020-3-156-55-64.

Full text

Abstract:

The article contains the data on creating and maintaining the collections in vitro of some ornamental plants – lilac, roses, tree peonies. The analysis of morphogenetic processes during microclonal propagation of lilac cultivars demonstrates well-defined correlation between susceptibility of this culture to mineral mixture of nutrient medium and plant genotype. Rose cultivars from different garden groups keep high growth capacity during 12 subculturing cycles on Murashige Skoog medium (MS) supplemented with 0.5 mg/l BAP. For all culturing tree-peonies cultivars Woody Plant Medium (WPM) with double content of Ca2+ ions and total exception of Cl- ions turns out to be more suitable. The opportunity of 10 lilac cultivars and 4 rose cultivars preservation in slow growth cultures was appreciated. The correlation between long-term cultivation in low temperature and genotype of ornamental plants cultivars was shown. Thus, 18 ºС turns out to be suitable for creation of slow-growth collection of all studied rose cultivars, and 14 ºС – only for 'Nina Weibull'. Maintaining of lilac microshoots at 10 ºС during 5 months practically did not act negatively on their viability.

APA, Harvard, Vancouver, ISO, and other styles

13

Van de Pol, P. A., and R. I. M.-Pierik. "Newest developments in rose (Rosa hybrid) propagation." Revista Chapingo Serie Horticultura I, no. 03 (March 1995): 15–22. http://dx.doi.org/10.5154/r.rchsh.1994.02.013.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Scagel, C. F. "Cultivar Specific Effects of Mycorrhizal Fungi on the Rooting of Miniature Rose Cuttings." Journal of Environmental Horticulture 19, no. 1 (March 1, 2001): 15–20. http://dx.doi.org/10.24266/0738-2898-19.1.15.

Full text

Abstract:

Abstract The benefits from root colonization by mycorrhizal fungi are thought to be highest when colonization occurs as early as possible during plant growth. We assessed whether addition of VA mycorrhizal fungi (VAMF) inoculum into rooting medium during cutting propagation would increase the quantity of rooting and the quality of rooted cuttings for five different cultivars of miniature roses (Rosa spp.). Four weeks after cuttings were stuck, the number of cuttings with roots for two cultivars that normally take longer to root, increased with addition of VAMF inoculum into the rooting medium. The combination of hormone treatment (IBA and NAA) and VAMF inoculum in the rooting medium increased the number of rooted cuttings and the number of roots per cutting for three cultivars when compared to cuttings that only received hormone treatment. Increases in root initiation and root growth of cuttings rooted in medium containing VAMF inoculum were not always associated with increased levels of root colonization by VAM fungi. Our results indicate that although adding VAMF inoculum into the rooting medium does not always increase root initiation, in some cultivars the combination of VAMF inoculum and rooting hormones can increase root initiation and potentially increase the quality of rooted cutting produced.

APA, Harvard, Vancouver, ISO, and other styles

15

Aegerter, B. J., J. J. Nuñez, and R. M. Davis. "Detection and Management of Downy Mildew in Rose Rootstock." Plant Disease 86, no. 12 (December 2002): 1363–68. http://dx.doi.org/10.1094/pdis.2002.86.12.1363.

Full text

Abstract:

A technique utilizing the polymerase chain reaction (PCR) was developed to investigate the occurrence and location of Peronospora sparsain dormant, woody rose tissues. PCR primers were designed to amplify the internal transcribed spacer region of the ribosomal DNA of the pathogen. Inhibition of the reaction by plant compounds was minimized by optimizing the reagents used in the extraction of DNA from roses and in the amplification reaction. The PCR assay was capable of detecting as little as 2 pg of DNA from P. sparsa against a background of 4 ng of DNA from rose cane cortex. With this method, DNA of P. sparsa was detected in the cortex of stem and root tissues of symptomatic plants. Pathogen DNA also was detected in the cortex of crown tissues of asymptomatic mother plants used as a source of propagation materials. Epifluorescent and differential interference contrast microscopy were used to confirm the presence of abundant hyphae and oospores within the stem cortex of infected canes. Preplant treatments of dormant rootstock cuttings in fungicides or hot water were evaluated during natural outbreaks of the disease in commercial rose nurseries. In three trials conducted over 2 years, a 10-min preplant dip in the systemic fungicides metalaxyl or mefenoxam at rates of 100 to 10,000 mg a.i./liter reduced the area under the disease progress curve by 63 to 76% relative to nontreated plots. The evidence from PCR assays, microscopy, and fungicide trials all support the occurrence of perennating infections of P. sparsa within rose. A technique utilizing the polymerase chain reaction (PCR) was developed to investigate the occurrence and location of Peronospora sparsain dormant, woody rose tissues. PCR primers were designed to amplify the internal transcribed spacer region of the ribosomal DNA of the pathogen. Inhibition of the reaction by plant compounds was minimized by optimizing the reagents used in the extraction of DNA from roses and in the amplification reaction. The PCR assay was capable of detecting as little as 2 pg of DNA from P. sparsa against a background of 4 ng of DNA from rose cane cortex. With this method, DNA of P. sparsa was detected in the cortex of stem and root tissues of symptomatic plants. Pathogen DNA also was detected in the cortex of crown tissues of asymptomatic mother plants used as a source of propagation materials. Epifluorescent and differential interference contrast microscopy were used to confirm the presence of abundant hyphae and oospores within the stem cortex of infected canes. Preplant treatments of dormant rootstock cuttings in fungicides or hot water were evaluated during natural outbreaks of the disease in commercial rose nurseries. In three trials conducted over 2 years, a 10-min preplant dip in the systemic fungicides metalaxyl or mefenoxam at rates of 100 to 10,000 mg a.i./liter reduced the area under the disease progress curve by 63 to 76% relative to nontreated plots. The evidence from PCR assays, microscopy, and fungicide trials all support the occurrence of perennating infections of P. sparsa within rose.

APA, Harvard, Vancouver, ISO, and other styles

16

Anderson, Robert G., and Wenwei Jia. "Developmental Stages of Single-stem Cut Rose Production." HortScience 31, no. 4 (August 1996): 654a—654. http://dx.doi.org/10.21273/hortsci.31.4.654a.

Full text

Abstract:

Commercial quality cut-roses were produced in a single-stem production system from single node cuttings. A significant advantage to single-stem rose production is that specific environments can be used for specific developmental stages of rose growth. In stage 1 (propagation), cuttings were treated with a 5-second dip in 500 ppm IBA/250 ppm NAA solution, placed in growing media in 8-cm pots, and placed under intermittent mist (5 second every 5 minutes) with growing medium temperature of 35°C. In stage 2 (axillary budbreak and stem development to visible pea size flower bud), rooted cuttings moved to benches (200 stems/m2) in a greenhouse at 14 to 16°C night, and plants received 12 hours supplemental light at 80 to 100 mol·m–2s–1. In stage 3 (stem elongation and flower bud development), small rose plants (30 to 35 cm tall with a pea-size flower bud) were moved to 100 stems/m2 in a greenhouse at 14 to 16°C night with ambient light. Through seven sequential crops of rose cuttings grown from Feb. through May 1995, rooting required a mean of 16 days, flower buds were visible in 42 days, and flower harvest required a mean of 58 days. Accumulated radiation and average temperatures through the spring had significant effects on the number of days in each developmental stage of rose growth.

APA, Harvard, Vancouver, ISO, and other styles

17

Domínguez, P. J., A. Gallegos, J. E. Macías-Díaz, and H. Vargas-Rodríguez. "Superenergy flux of Einstein–Rosen waves." International Journal of Modern Physics D 27, no. 07 (May 2018): 1850072. http://dx.doi.org/10.1142/s0218271818500724.

Full text

Abstract:

In this work, we consider the propagation speed of the superenergy flux associated to the Einstein–Rosen cylindrical waves propagating in vacuum and over the background of the gravitational field of an infinitely long mass line distribution. The velocity of the flux is determined considering the reference frame in which the super-Poynting vector vanishes. This reference frame is then considered as comoving with the flux. The explicit expressions for the velocities are given with respect to a reference frame at rest with the symmetry axis.

APA, Harvard, Vancouver, ISO, and other styles

18

Mills, Frederick V. "The Society in Scotland for Propagating Christian Knowledge In British North America, 1730–1775." Church History 63, no. 1 (March 1994): 15–30. http://dx.doi.org/10.2307/3167830.

Full text

Abstract:

Three major Protestant missionary organizations—the Company for the ropagation of the Gospel in New England (the NEC, founded 1649), the Society for the Propagation of the Gospel in Foreign Parts (SPG, founded 1701), and the Society in Scotland for Propagating Christian Knowledge (SSPCK, founded 1709)—all played significant roles in Christianizing and civilizing the inhabitants of British North America. The New England Company had the longest history and is the oldest Protestant missionary organization. The Society for the Propagation of the Gospel in Foreign Parts sent no fewer than three hundred missionaries to America between 1701 and 1783. While the NEC and the SPG have received scholarly attention, the Society in Scotland for Propagating Christian Knowledge has been virtually ignored.

APA, Harvard, Vancouver, ISO, and other styles

19

Chu, Chien-Young. "Budded cuttings for propagating roses." Scientia Horticulturae 43, no. 1-2 (June 1990): 163–68. http://dx.doi.org/10.1016/0304-4238(90)90047-i.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Thompson, Alice B., Anne Juel, and Andrew L. Hazel. "Multiple finger propagation modes in Hele-Shaw channels of variable depth." Journal of Fluid Mechanics 746 (March 28, 2014): 123–64. http://dx.doi.org/10.1017/jfm.2014.100.

Full text

Abstract:

AbstractWe consider the propagation of an air finger into a wide fluid-filled channel with a spatially varying depth profile. Our aim is to understand the origin of the multiple coexisting families of both steady and oscillatory propagating fingers previously observed in experiments in axially uniform channels each containing a centred step-like occlusion. We find that a depth-averaged model can reproduce all the finger propagation modes observed experimentally. In addition, the model reveals new modes for symmetric finger propagation. The inclusion of a spatially variable channel depth in the depth-averaged equations leads to: (i) a variable mobility coefficient within the fluid domain due to variations in viscous resistance of the channel; and (ii) a variable transverse curvature term in the dynamic boundary condition that modifies the pressure jump over the air–liquid interface. We use our model to examine the roles of these two distinct effects and find that both contribute to the steady bifurcation structure, while the transverse curvature term is responsible for the distinctive oscillatory propagation modes.

APA, Harvard, Vancouver, ISO, and other styles

21

Ogungbeni, John I., Amaka R. Obiamalu, Samuel Ssemambo, and Charles M. Bazibu. "The roles of academic libraries in propagating open science." Information Development 34, no. 2 (November 10, 2016): 113–21. http://dx.doi.org/10.1177/0266666916678444.

Full text

Abstract:

This study investigates the roles of academic libraries in propagating Open Science. The study is a qualitative survey based on literature review. Various definitions of open science from different scholars and schools of thought were examined. Research articles on the effects of open science on research and the place of academic libraries in scientific research were reviewed. Open science enhances collaborations and sharing of resources among researchers. Metadata related activities are more prevalent due to open science. Open science has increased the relevance of science to our environment and world issues like privacy and the rightful author of scientific data are still some of the challenges facing open science. Academic libraries continue to take steps to be involved as key players in the propagation of open science through advocacy, building of institutional data repositories and serving as hubs for scientific collaboration among others. Academic libraries have to do more in the area of advocacy and provision of data repositories.

APA, Harvard, Vancouver, ISO, and other styles

22

Bae, Kee-Hwa, Myung-Suk Ko, Nam-Young Kim, Jae-Mo Song, and Gwan-Pil Song. "In vitro propagation and multiple shoot induction of Rhodiola rosea L. by axillary bud culture." Journal of Plant Biotechnology 39, no. 2 (June 30, 2012): 114–20. http://dx.doi.org/10.5010/jpb.2012.39.2.114.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Zhang, Jiaqi, Ke Wang, and Lanwei Chen. "Fill-In and Boiling Transition Characteristics during the Liquid Oxygen Chill-Down Process in a Vertical Exit-Contracted Pipe." International Journal of Aerospace Engineering 2022 (August 23, 2022): 1–22. http://dx.doi.org/10.1155/2022/5899199.

Full text

Abstract:

Liquid oxygen chill-down in a vertical exit-contracted pipe was investigated experimentally. The wall temperatures were recorded in detail to describe the filling and chill-down process of the experimental section. Two quenching fronts, the exit one and the inlet one, were detected, and their propagations were found. Results show that the chill-down process is controlled mainly by the formation and propagation of quenching front, which are determined by the pressure level. With the increase of pressure, the roles of both propagation of quenching front and inlet quenching front undergo decreasing. On the vertical section, the effect of circumferential position was discussed in detail and the dominant point was identified, which determines the boiling transition time of the dominated points on the current cross-section. Based on the experimental data, two correlations were suggested for dominant point and dominated points, respectively, to predict heat flux on Leidenfrost, heat transfer coefficient on Leidenfrost, and critical heat flux. One equation was approved to predict heat transfer coefficient on critical heat flux point for both sorts of points. All of these correlations could produce reliable predictions.

APA, Harvard, Vancouver, ISO, and other styles

24

Liu, Fei, Bin Wang, and In-Sik Kang. "Roles of Barotropic Convective Momentum Transport in the Intraseasonal Oscillation*." Journal of Climate 28, no. 12 (June 11, 2015): 4908–20. http://dx.doi.org/10.1175/jcli-d-14-00575.1.

Full text

Abstract:

Abstract Both observational data analysis and model simulations suggest that convective momentum transport (CMT) by cumulus convection may play a significant role in the intraseasonal oscillations (ISO) by redistributing atmospheric momentum vertically through fast convective mixing process. The authors present a simple theoretical model for the ISO by parameterizing the cumulus momentum transport process in which the CMT tends to produce barotropic wind anomalies that will affect the frictional planetary boundary layer (PBL). In the model with equatorial easterly vertical wind shear (VWS), it is found that the barotropic CMT tends to select most unstable planetary-scale waves because CMT suppresses the equatorial Ekman pumping of short waves, which reduces the shortwave instability from the PBL moisture convergence and accelerates the shortwave propagation. The model with subtropical easterly VWS has behavior that can be qualitatively different from the model with equatorial easterly VWS and has robust northward propagation. The basic mechanism of this northward propagation is that the CMT accelerates the barotropic cyclonic wind to the north of ISO, which will enhance the precipitation by PBL Ekman pumping and favor the northward propagation. The simulated northward propagation is sensitive to the strength and location of the seasonal-mean easterly VWS. These results suggest that accurate simulation of the climatological-mean state is critical for reproducing the realistic ISO in general circulation models.

APA, Harvard, Vancouver, ISO, and other styles

25

Johnston, Daniel, Brian R. Christie, Andreas Frick, Richard Gray, Dax A. Hoffman, Lalania K. Schexnayder, Shigeo Watanabe, and Li-Lian Yuan. "Active dendrites, potassium channels and synaptic plasticity." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 358, no. 1432 (April 29, 2003): 667–74. http://dx.doi.org/10.1098/rstb.2002.1248.

Full text

Abstract:

The dendrites of CA1 pyramidal neurons in the hippocampus express numerous types of voltage-gated ion channel, but the distributions or densities of many of these channels are very non-uniform. Sodium channels in the dendrites are responsible for action potential (AP) propagation from the axon into the dendrites (back-propagation); calcium channels are responsible for local changes in dendritic calcium concentrations following back-propagating APs and synaptic potentials; and potassium channels help regulate overall dendritic excitability. Several lines of evidence are presented here to suggest that back-propagating APs, when coincident with excitatory synaptic input, can lead to the induction of either long-term depression (LTD) or long-term potentiation (LTP). The induction of LTD or LTP is correlated with the magnitude of the rise in intracellular calcium. When brief bursts of synaptic potentials are paired with postsynaptic APs in a theta-burst pairing paradigm, the induction of LTP is dependent on the invasion of the AP into the dendritic tree. The amplitude of the AP in the dendrites is dependent, in part, on the activity of a transient, A-type potassium channel that is expressed at high density in the dendrites and correlates with the induction of the LTP. Furthermore, during the expression phase of the LTP, there are local changes in dendritic excitability that may result from modulation of the functioning of this transient potassium channel. The results support the view that the active properties of dendrites play important roles in synaptic integration and synaptic plasticity of these neurons.

APA, Harvard, Vancouver, ISO, and other styles

26

Chung, Jun Young, and Manoj K. Chaudhury. "Roles of discontinuities in bio-inspired adhesive pads." Journal of The Royal Society Interface 2, no. 2 (February 8, 2005): 55–61. http://dx.doi.org/10.1098/rsif.2004.0020.

Full text

Abstract:

Morphological intricacies of the biological attachment pads generate considerable interest owing to their remarkable ability to control adhesion to various surfaces. Motivated by the adhesive microstructures of insects, we examine the behaviour of adhesion and crack propagation in patterned adhesive films. These films are made of silicone elastomers that were patterned with lateral, longitudinal or crosswise incisions from which a thin silanized glass plate was removed in a displacement-controlled peel experiment. The behaviours of crack propagation on these patterned adhesive films are controlled by simple incision patterns, their depths and spacing. With the crosswise incisions, significant enhancement (×10–20) of fracture energy has been achieved. These findings point towards an important mechanism by which of biological organisms might enhance adhesion, and provide a simple design principle for manipulating the interfacial fracture in a variety of artificial attachment devices.

APA, Harvard, Vancouver, ISO, and other styles

27

Hilaire, Rolston St, and Carlos A. Fierro Berwart. "Three Mussaenda Cultivars Propagated by Stem Cuttings Exhibit Variation in Rooting in Response to Hormone and Rooting Conditions." HortTechnology 10, no. 4 (January 2000): 780–84. http://dx.doi.org/10.21273/horttech.10.4.780.

Full text

Abstract:

The effects of 1H-indole-3-butyric acid (IBA), cutting position on stock plants, the date of propagation, the type of rooting substrate and temperature on rooting of mussaenda (Mussaenda erythrophylla Schumach. & Thonn. `Ashanti Blood' and `Rosea', and Mussaenda philippica A. Rich `Aurorae') stem cuttings were determined. Cuttings of `Ashanti Blood' produced the largest number of roots when treated with 15 mmol (3000 ppm) IBA and rooted in perlite at 29 °C (84 °F). Cutting position on stock plants did not affect rooting in any of the three cultivars. Propagation date and temperature of the rooting medium affected root numbers in `Aurorae'. With `Rosea', only the type of rooting substrate affected root number. Rooting percentage was 22%, 48%, and 39% in `Ashanti Blood', `Aurorae', and `Rosea' respectively. After 30 days of propagation average root length was 4, 12, and 4 mm (0.2, 0.5, and 0.2 inch) in `Ashanti Blood', `Aurorae', and `Rosea' respectively. Growers must determine precise rooting conditions for each cultivar to obtain consistent rooting of cuttings. This process may not be economically feasible on a commercial basis because rooting percentages are relatively low. We conclude that other methods of clonal propagation need to be evaluated before uniform rooted stem cuttings of mussaenda can be produced economically.

APA, Harvard, Vancouver, ISO, and other styles

28

Metzger, R., L. Belbahri, G. Calmin, N. Badin, and F. Lefort. "First Report of Pythium intermedium Causing Root Rot on Rosa canina Rootstock in France." Plant Disease 91, no. 8 (August 2007): 1055. http://dx.doi.org/10.1094/pdis-91-8-1055b.

Full text

Abstract:

Old cultivars of roses (Rosa spp.) established on Rosa canina as rootstock are grown in field collections in the repository at Gaillard in eastern France, close to the Swiss border. During June 2005 and July 2006, several rose plants in full vegetation were severely wilted, leading ultimately to plant death. Necrotic lesions were present on the roots, and marginal tissue was excised and incubated in the dark at 20°C on PARP V8 agar plates (1). Similar isolates were obtained in both years, which were inoculated within 4 days on V8 agar medium and incubated at 25°C. The pathogen colonies grew approximately 30 mm daily on V8 agar. Colonies on corn meal agar (CMA) (1) were submerged, with or without a vague radiate pattern on potato carrot agar. Main hyphae were as much as 7 μm wide. Sporangia and zoospores were not produced. Hyphal swellings as much as 25 μm in diameter were abundant, terminal, and sometimes intercalary, often forming regular, dense chains in basipetal succession at hyphal tips and readily liberated. The morphological characters matched those described for Pythium intermedium (2). DNA sequencing of the ITS rDNA (ITS1, ITS2, and 5.8S rDNA) was generated using primers ITS5 and ITS4 in primary PCR (35 cycles: 96°C for 1 min, 55°C for 1 min, and 72°C for 2 min) and sequencing reactions (1). All isolates yielded identical ITS sequences, which were identical to the ex-type strain of P. intermedium, CBS 266.38 (GenBank Accession No. AY598647). The ITS sequence was deposited as GenBank Accession No. EF078693 (National Center for Biotechnology Information, NCBI, Bethesda, MD). Pathogenicity testing was performed on 3-year-old Rosa canina rootstocks from clonal propagation in 25 cm in diameter and 40 cm deep pots of compost 297 (Ricoter, Aarberg, Switzerland). Five-day-old mycelial plugs of our isolates grown on CMA (1) were inoculated in two pots, and roots were mechanically wounded. Sterile plugs were used on two control plants set aside. All plants were kept for 2 weeks at 20°C in a glasshouse with sufficient watering. Extensive necrotic lesions developed on inoculated roots, and severe wilting and leaves drying out were also observed. The controls showed no symptoms. P. intermedium was reisolated from margins of root lesions, thus fulfilling the postulates of Koch. P. intermedium was originally isolated from dead plant material (2) but is known as a typical soil inhabitant. It also has been isolated from water and living material from numerous plant species, but never from the genus Rosa until now. To our knowledge, this is the first record of P. intermedium on Rosa spp. grafted on Rosa canina in France. References: (1) L. Belbahri et al. FEMS Microbiol Lett 255:209, 2006. (2) A. J. van der Plaats-Niterink. Stud. Mycol. 21:1, 1981.

APA, Harvard, Vancouver, ISO, and other styles

29

Mortensen, Peter, Hao Gao, Godfrey Smith, and Radostin D. Simitev. "Action potential propagation and block in a model of atrial tissue with myocyte–fibroblast coupling." Mathematical Medicine and Biology: A Journal of the IMA 38, no. 1 (January 8, 2021): 106–31. http://dx.doi.org/10.1093/imammb/dqaa014.

Full text

Abstract:

Abstract The electrical coupling between myocytes and fibroblasts and the spacial distribution of fibroblasts within myocardial tissues are significant factors in triggering and sustaining cardiac arrhythmias, but their roles are poorly understood. This article describes both direct numerical simulations and an asymptotic theory of propagation and block of electrical excitation in a model of atrial tissue with myocyte–fibroblast coupling. In particular, three idealized fibroblast distributions are introduced: uniform distribution, fibroblast barrier and myocyte strait—all believed to be constituent blocks of realistic fibroblast distributions. Primary action potential biomarkers including conduction velocity, peak potential and triangulation index are estimated from direct simulations in all cases. Propagation block is found to occur at certain critical values of the parameters defining each idealized fibroblast distribution, and these critical values are accurately determined. An asymptotic theory proposed earlier is extended and applied to the case of a uniform fibroblast distribution. Biomarker values are obtained from hybrid analytical-numerical solutions of coupled fast-time and slow-time periodic boundary value problems and compare well to direct numerical simulations. The boundary of absolute refractoriness is determined solely by the fast-time problem and is found to depend on the values of the myocyte potential and on the slow inactivation variable of the sodium current ahead of the propagating pulse. In turn, these quantities are estimated from the slow-time problem using a regular perturbation expansion to find the steady state of the coupled myocyte–fibroblast kinetics. The asymptotic theory gives a simple analytical expression that captures with remarkable accuracy the block of propagation in the presence of fibroblasts.

APA, Harvard, Vancouver, ISO, and other styles

30

Oelmüller, Ralf. "Threat at One End of the Plant: What Travels to Inform the Other Parts?" International Journal of Molecular Sciences 22, no. 6 (March 19, 2021): 3152. http://dx.doi.org/10.3390/ijms22063152.

Full text

Abstract:

Adaptation and response to environmental changes require dynamic and fast information distribution within the plant body. If one part of a plant is exposed to stress, attacked by other organisms or exposed to any other kind of threat, the information travels to neighboring organs and even neighboring plants and activates appropriate responses. The information flow is mediated by fast-traveling small metabolites, hormones, proteins/peptides, RNAs or volatiles. Electric and hydraulic waves also participate in signal propagation. The signaling molecules move from one cell to the neighboring cell, via the plasmodesmata, through the apoplast, within the vascular tissue or—as volatiles—through the air. A threat-specific response in a systemic tissue probably requires a combination of different traveling compounds. The propagating signals must travel over long distances and multiple barriers, and the signal intensity declines with increasing distance. This requires permanent amplification processes, feedback loops and cross-talks among the different traveling molecules and probably a short-term memory, to refresh the propagation process. Recent studies show that volatiles activate defense responses in systemic tissues but also play important roles in the maintenance of the propagation of traveling signals within the plant. The distal organs can respond immediately to the systemic signals or memorize the threat information and respond faster and stronger when they are exposed again to the same or even another threat. Transmission and storage of information is accompanied by loss of specificity about the threat that activated the process. I summarize our knowledge about the proposed long-distance traveling compounds and discuss their possible connections.

APA, Harvard, Vancouver, ISO, and other styles

31

Raisutis, Renaldas, Rymantas Kazys, Liudas Mazeika, Vykintas Samaitis, and Egidijus Zukauskas. "Propagation of Ultrasonic Guided Waves in Composite Multi-Wire Ropes." Materials 9, no. 6 (June 6, 2016): 451. http://dx.doi.org/10.3390/ma9060451.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Tang, Qi, Peng Wu, Huiqing Chen, and Guohui Li. "Pleiotropic roles of the ubiquitin-proteasome system during viral propagation." Life Sciences 207 (August 2018): 350–54. http://dx.doi.org/10.1016/j.lfs.2018.06.014.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Tan, Xin, Ming Bao, Dennis L. Hartmann, and Paulo Ceppi. "The Role of Synoptic Waves in the Formation and Maintenance of the Western Hemisphere Circulation Pattern." Journal of Climate 30, no. 24 (December 2017): 10259–74. http://dx.doi.org/10.1175/jcli-d-17-0158.1.

Full text

Abstract:

Previous studies have demonstrated that the NAO, the leading mode of atmospheric low-frequency variability over the North Atlantic, could be linked to northeast Pacific climate variability via the downstream propagation of synoptic waves. In those studies, the NAO and the northeast Pacific climate variability are considered as two separate modes that explain the variance over the North Atlantic sector and the east Pacific–North American sector, respectively. A newly identified low-frequency atmospheric regime—the Western Hemisphere (WH) circulation pattern—provides a unique example of a mode of variability that accounts for variance over the whole North Atlantic–North American–North Pacific sector. The role of synoptic waves in the formation and maintenance of the WH pattern is investigated using the ECMWF reanalysis datasets. Persistent WH events are characterized by the propagation of quasi-stationary Rossby waves across the North Pacific–North American–North Atlantic regions and by associated storm-track anomalies. The eddy-induced low-frequency height anomalies maintain the anomalous low-frequency ridge over the Gulf of Alaska, which induces more equatorward propagation of synoptic waves on its downstream side. The eddy forcing favors the strengthening of the midlatitude jet and the deepening of the mid-to-high-latitude trough over the North Atlantic, whereas the deepening of the trough over eastern North America mostly arises from the quasi-stationary waves propagating from the North Pacific. A case study for the 2013/14 winter is examined to illustrate the downstream development of synoptic waves. The roles of synoptic waves in the formation and maintenance of the WH pattern and in linking the northeast Pacific ridge anomaly with the NAO are discussed.

APA, Harvard, Vancouver, ISO, and other styles

34

Wang, Yufeng, Xu Yang, Yanyou Chai, Xuguang Yang, and Qi Tian. "A Corporate Reputation Propagation Dynamic Model." Mathematical Problems in Engineering 2021 (October 27, 2021): 1–11. http://dx.doi.org/10.1155/2021/8141105.

Full text

Abstract:

This study analyzes the process of corporate reputation (CR) propagation. We consider that different positions play different roles via social word of mouth (sWOM). In essence, our interest lies in the following question: how does sWOM affect the process of CR propagation? As a benchmark, we develop a dynamic model to reflect the factors and laws influencing corporate reputation propagation. We find that the stability of the system is not what corporations want to see in the propagation of positive CR after analyzing two basic reproduction numbers and conducting a numerical simulation. Another important finding is that stability is what corporations expect in the propagation of negative CR. This study makes the logical analysis of the relationship between CR and consumer loyalty more complete and helps us to clearly understand the overall process of CR propagation. The study provides a new way to analyze the law of CR propagation and can provide a reference for decision-making for corporations.

APA, Harvard, Vancouver, ISO, and other styles

35

Harada, Yayoi, Atsushi Goto, Hiroshi Hasegawa, Norihisa Fujikawa, Hiroaki Naoe, and Toshihiko Hirooka. "A Major Stratospheric Sudden Warming Event in January 2009." Journal of the Atmospheric Sciences 67, no. 6 (June 1, 2010): 2052–69. http://dx.doi.org/10.1175/2009jas3320.1.

Full text

Abstract:

Abstract The major stratospheric sudden warming (SSW) event of January 2009 is analyzed using the Japan Meteorological Agency (JMA) Climate Data Assimilation System (JCDAS). This SSW event is characterized by the extraordinary predominance of the planetary-scale wave of zonal wavenumber 2 (wave 2). The total amount of the upward Eliassen–Palm (EP) flux for wave 2 was the strongest since the winter of 1978/79. It is found that the remarkable development of the upper troposphere ridge over Alaska played important roles in the SSW in January 2009. During the first development stage, the ridge excited wave packets upward as well as eastward over around Alaska. The eastward-propagating packets intensified a trough over eastern Siberia, which led to the development of the planetary wave over eastern Siberia during the second development stage. The results of this study indicate that the pronounced wave-2 pattern observed in the stratosphere was brought about by accumulative effects of rather localized propagation of wave packets from the troposphere during the course of this SSW event rather than by the ubiquitous propagation of planetary-scale disturbances in the troposphere. The features of the SSW in January 2009 are quite similar to those during the major stratospheric warming event in February 1989: both SSWs are characterized by the predominance of wave 2, the remarkable development of the upper troposphere ridge over around Alaska, and positive SSTs in the eastern part of the North Pacific corresponding to a La Niña condition.

APA, Harvard, Vancouver, ISO, and other styles

36

Ivanoska, Ilinka, Luisina Pastorino, and Massimiliano Zanin. "Assessing Identifiability in Airport Delay Propagation Roles Through Deep Learning Classification." IEEE Access 10 (2022): 28520–34. http://dx.doi.org/10.1109/access.2022.3158313.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Li, Xican. "Guangxiao Temple (Guangzhou) and its Multi Roles in the Development of Asia-Pacific Buddhism." Asian Culture and History 8, no. 1 (September 2, 2015): 45. http://dx.doi.org/10.5539/ach.v8n1p45.

Full text

Abstract:

Guangxiao Temple is located in Guangzhou (a coastal city in Southern China), and has a long history. The present study conducted an onsite investigation of Guangxiao’s precious Buddhist relics, and combined this with a textual analysis of Annals of Guangxiao Temple, to discuss its history and multi-roles in Asia-Pacific Buddhism. It is argued that Guangxiao’s 1,700-year history can be seen as a microcosm of Chinese Buddhist history. As the special geographical position, Guangxiao Temple often acted as a stopover point for Asian missionary monks in the past. It also played a central role in propagating various elements of Buddhism, including precepts school, Chan (Zen), esoteric (Shingon) Buddhism, and Pure Land. Particulary, Huineng, the sixth Chinese patriarch of Chan Buddhism, made his first public Chan lecture and was tonsured in Guangxiao Temple; Esoteric Buddhist master Amoghavajra’s first teaching of esoteric Buddhism is thought to have been in Guangxiao Temple. It was also a translation center in Southern China, where Buddhist scriptures were translated by Yijing and the Shurangama-sūtra was translated by Paramitiin – these texts served to promote the establishment of Mahāyāna Buddhism as the mainstream philosophy of Chinese (even Asia-Pacific) Buddhism. With the development of globalization, Guangxiao Temple is now exerting even more positive effects on the propagation of Buddhism via international communications and Buddhist tourism. Our onsite investigation also identificated the words in the mantra pillar (826 B.C). This significant finding suggests the popularity of esoteric Buddhism in Sourthern China, and will be helpful for Buddhist study in the future.

APA, Harvard, Vancouver, ISO, and other styles

38

Feng, Yan Jun, and Xiu Wei Shi. "Hydraulic Fracturing Process: Roles of In Situ Stress and Rock Strength." Advanced Materials Research 616-618 (December 2012): 435–40. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.435.

Full text

Abstract:

This paper presents results of a comprehensive study involving analytical and field experimental investigations into the factors controlling the hydraulic fracturing process. Analytical theories for fracture initiation of vertical and horizontal borehole are reviewed. The initiation and propagation process of hydraulic fracturing is performed in the field by means of hydraulic fracturing and stepwise hydraulic fracturing, the effect of factors such as in-situ stress and rock strength on fracture propagation process is studied and discussed. The fracture initiation pressures estimated from the analytical model and field experiments are compared as well as the fracturing process during case 1and case 2. Results from the analytical model and field experiments conducted in this study are interpreted with a particular effort to enlighten the factors controlling the hydraulic fracturing process.

APA, Harvard, Vancouver, ISO, and other styles

39

Guzman, Frederick, Yasamin Fazeli, Meagan Khuu, Kelsey Salcido, Sarah Singh, and Claudia A. Benavente. "Retinoblastoma Tumor Suppressor Protein Roles in Epigenetic Regulation." Cancers 12, no. 10 (September 29, 2020): 2807. http://dx.doi.org/10.3390/cancers12102807.

Full text

Abstract:

Mutations that result in the loss of function of pRB were first identified in retinoblastoma and since then have been associated with the propagation of various forms of cancer. pRB is best known for its key role as a transcriptional regulator during cell cycle exit. Beyond the ability of pRB to regulate transcription of cell cycle progression genes, pRB can remodel chromatin to exert several of its other biological roles. In this review, we discuss the diverse functions of pRB in epigenetic regulation including nucleosome mobilization, histone modifications, DNA methylation and non-coding RNAs.

APA, Harvard, Vancouver, ISO, and other styles

40

Turner, Jay D., Richard Williamson, Kaith K. Almefty, Peter Nakaji, Randall Porter, Victor Tse, and M. Yashar S. Kalani. "The many roles of microRNAs in brain tumor biology." Neurosurgical Focus 28, no. 1 (January 2010): E3. http://dx.doi.org/10.3171/2009.10.focus09207.

Full text

Abstract:

MicroRNAs (miRNAs) are now recognized as the primary RNAs involved in the purposeful silencing of the cell's own message. In addition to the established role of miRNAs as developmental regulators of normal cellular function, they have recently been shown to be important players in pathological states such as cancer. The authors review the literature on the role of miRNAs in the formation and propagation of gliomas and medulloblastomas, highlighting the potential of these molecules and their inhibitors as therapeutics.

APA, Harvard, Vancouver, ISO, and other styles

41

Jia, Yunzhong, Zhaohui Lu, Hong Liu, Jiehao Wang, Yugang Cheng, and Xinwei Zhang. "Fracture Propagation and Morphology Due to Non-Aqueous Fracturing: Competing Roles between Fluid Characteristics and In Situ Stress State." Minerals 10, no. 5 (May 10, 2020): 428. http://dx.doi.org/10.3390/min10050428.

Full text

Abstract:

Non-aqueous or gaseous stimulants are alternative working fluids to water for hydraulic fracturing in shale reservoirs, which offer advantages including conserving water, avoiding clay swelling and decreasing formation damage. Hence, it is crucial to understand fluid-driven fracture propagation and morphology in shale formations. In this research, we conduct fracturing experiments on shale samples with water, liquid carbon dioxide, and supercritical carbon dioxide to explore the effect of fluid characteristics and in situ stress on fracture propagation and morphology. Moreover, a numerical model that couples rock property heterogeneity, micro-scale damage and fluid flow was built to compare with experimental observations. Our results indicate that the competing roles between fluid viscosity and in situ stress determine fluid-driven fracture propagation and morphology during the fracturing process. From the macroscopic aspect, fluid-driven fractures propagate to the direction of maximum horizontal stress direction. From the microscopic aspect, low viscosity fluid easily penetrates into pore throats and creates branches and secondary fractures, which may deflect the main fracture and eventually form the fracture networks. Our results provide a new understanding of fluid-driven fracture propagation, which is beneficial to fracturing fluid selection and fracturing strategy optimization for shale gas hydraulic fracturing operations.

APA, Harvard, Vancouver, ISO, and other styles

42

Katanaev, M. O. "Passing the Einstein–Rosen bridge." Modern Physics Letters A 29, no. 17 (May 26, 2014): 1450090. http://dx.doi.org/10.1142/s0217732314500904.

Full text

Abstract:

A test particle moving along geodesic line in a spacetime has three physical propagating degrees of freedom and one unphysical gauge degree. We relax the requirement of geodesic completeness of a spacetime. Instead, we require test particles trajectories to be smooth and complete only for physical degrees of freedom. Test particles trajectories for Einstein–Rosen bridge are proved to be smooth and complete in the physical sector, and particles can freely penetrate the bridge in both directions.

APA, Harvard, Vancouver, ISO, and other styles

43

Khela, Harmon, Sweta Sudhir, Maria Lugo-Fagundo, Bachchu Lal, Hernando Lopez-Bertoni, and John Laterra. "STEM-27. miR-10b-5p MODULATES 5hmC EXPRESSION AND THE STEM-LIKE PHENOTYPE IN GBM." Neuro-Oncology 22, Supplement_2 (November 2020): ii202. http://dx.doi.org/10.1093/neuonc/noaa215.844.

Full text

Abstract:

Abstract Epigenetic alterations such as DNA methylation and dysregulation of non-coding RNAs (e.g. miRNAs) are found in all types of cancer and are thought to play important roles in tumorigenesis. GBM is characterized by small subsets of cells, referred to as glioma stem cells (GSCs), that display stem-like properties implicated in tumor initiation, therapeutic resistance, and recurrence. DNA methylation patterns are altered in GBM and GSCs and are thought to play critical roles in tumor initiation and propagation. DNA methylation is a reversible process catalyzed, in part, by the ten-eleven translocation (TET) family of enzymes. These enzymes function as deoxygenases that catalyze the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). Multiple studies found negative correlations between 5hmC levels and glioma grade and loss of 5hmC correlates with poor prognosis of GBM patients. However, the mechanisms leading to the loss of 5hmC in glioma and the role this phenomenon plays in gliomagenesis remains poorly understood. We found that Sox2 expression decreases TET2 expression and its product 5hmC in GSCs and identified miR-10b-5p as a molecular intermediary of this process. We show that miR-10b-5p expression is high in GBM compared to non-tumor in clinical specimens and high levels of this miRNA correlate with poor patient outcome. Expression of transgenic miR-10b-5p enhanced sphere formation capacity of GSCs and the expression of stem cell markers and drivers. Additionally, using a combination of molecular and biochemical endpoints, we show that miR-10b-5p modifies 5hmC levels by regulating TET2 in GSCs. Finally, we show that repression of miR-10b-5p increases 5hmC levels and inhibits tumor propagation in GBM xenograft models. Taken together, these results present a new molecular mechanism that controls 5hmC and the tumor propagating capacity of GSCs and suggests that miR-10b-5p inhibition and other strategies for enhancing TET2 function can be developed to treat GBM.

APA, Harvard, Vancouver, ISO, and other styles

44

Petruzzelu, Guy J. "Cell Biology of Invasion and Metastasis." Otolaryngology–Head and Neck Surgery 112, no. 5 (May 1995): P91. http://dx.doi.org/10.1016/s0194-5998(05)80213-x.

Full text

Abstract:

Educational objectives: To understand the basic mechanisms of vascular and soft tissue invasion by tumors and to review the roles of specific tumor products in the propagation of squamous cell carcinoma metastases.

APA, Harvard, Vancouver, ISO, and other styles

45

Rostami, Javad, Peter W. Tse, and Maodan Yuan. "Detection of broken wires in elevator wire ropes with ultrasonic guided waves and tone-burst wavelet." Structural Health Monitoring 19, no. 2 (June 12, 2019): 481–94. http://dx.doi.org/10.1177/1475921719855915.

Full text

Abstract:

Elevator wire ropes with polymer cores hold and hoist heavy fluctuating loads in a corrosive environment. Such working condition causes metal fatigue, which together with abrasion around pulleys leads to progressive loss of the metallic cross section. This can be seen in the forms of a roughened and pitted surface of the ropes, reduction in diameter, and broken wires. Therefore, their deterioration must be monitored so that any unexpected damage or corrosion can be detected before it causes a fatal accident. Ultrasonic-guided wave-based inspection, which has proved its capability in nondestructive testing of platelike structures such as tubes and pipes, can monitor the cross section of wire ropes in their entire length from a single point. However, guided waves have drawn less attention for defect detection purposes in wire ropes. This article reports the condition monitoring of a steel wire rope from a hoisting elevator with broken wires as a result of corrosive environment and fatigue. Finite element analysis was conducted as a baseline to study guided wave propagation in wire ropes and plot dispersion curves. Guided wave propagation in wire ropes was experimentally investigated on a newly built cable stretching machine equipped with a load sensor under different amount of tensile loading. To expose the indication of broken wires, the recorded signals were analyzed by tailor-made continuous wavelet transform called tone burst wavelet.

APA, Harvard, Vancouver, ISO, and other styles

46

Park, Jae-Hun, and D. Randolph Watts. "Internal Tides in the Southwestern Japan/East Sea." Journal of Physical Oceanography 36, no. 1 (January 1, 2006): 22–34. http://dx.doi.org/10.1175/jpo2846.1.

Full text

Abstract:

Abstract This paper investigates the internal tidal energy distribution in the southwestern Japan/East Sea using vertical round-trip travel time (τ) data from 23 pressure-sensor-equipped inverted echo sounders (PIES). The τ records are analyzed by bandpass filtering to separate time-dependent variability of the semidiurnal and diurnal bands. The semidiurnal internal tides exhibit a horizontal beam pattern of high energy, propagating into the open basin. They originate from a restricted portion of the shelf break where the Korea Strait enters the Ulleung Basin. The generation appears to occur at ∼200-m water depth near 35.5°–35.7°N and 130°–131°E, where the slope of bottom topography matches that of the wave characteristics, coinciding with the location where the semidiurnal barotropic cross-slope tidal currents are strongest. Maximum vertical displacement of the thermocline interpreted as a long-wave first baroclinic mode from the measured τ is about 25 m near the generation region. Annual and monthly variations of the propagation patterns and generation energy levels are observed, and these are closely associated with changes in the mesoscale circulation and stratification. Eastward (westward) refraction is observed when a warm (cold) eddy crosses the path of internal tide propagation. Moreover, when the generation region is invaded by cold eddies that spoil the match between shelf break and thermocline depth, the internal tidal energy level decreases by a factor of about 2. A simple geometric optics model is proposed to explain the observed horizontal refraction of the beam of semidiurnal internal tides in which stratification and current shear play essential roles. In contrast, diurnal internal tides are observed to be trapped along the continental slope region around 36°N.

APA, Harvard, Vancouver, ISO, and other styles

47

Man, Yu Yan, Chi Zhang, Nan Wang, Li Ming Zhang, and Hao Ming Wang. "Effect of Substation Network on Transformer PD Monitoring." Applied Mechanics and Materials 672-674 (October 2014): 842–47. http://dx.doi.org/10.4028/www.scientific.net/amm.672-674.842.

Full text

Abstract:

In this paper, a simulation model for the propagation of transformer PD pulse has been constructed,and the propagation of PD in a real substation were investigated. We also studied the frequency characteristics of currents at different detection positions, and the influences of substation network are analyzed in aspects of system resonant frequency. The optimal detection position and the optimal measuring band are proposed. The results show that, the calculated range of substation network and capacitive apparatus play the key roles in impedance characteristics.

APA, Harvard, Vancouver, ISO, and other styles

48

Lin, Shuhao, Daiki Hirayama, Gembu Maryu, Kimiya Matsuda, Naoya Hino, Eriko Deguchi, Kazuhiro Aoki, Ryo Iwamoto, Kenta Terai, and Michiyuki Matsuda. "Redundant roles of EGFR ligands in the ERK activation waves during collective cell migration." Life Science Alliance 5, no. 1 (October 19, 2021): e202101206. http://dx.doi.org/10.26508/lsa.202101206.

Full text

Abstract:

Epidermal growth factor receptor (EGFR) plays a pivotal role in collective cell migration by mediating cell-to-cell propagation of extracellular signal-regulated kinase (ERK) activation. Here, we aimed to determine which EGFR ligands mediate the ERK activation waves. We found that epidermal growth factor (EGF)–deficient cells exhibited lower basal ERK activity than the cells deficient in heparin-binding EGF (HBEGF), transforming growth factor alpha (TGFα) or epiregulin (EREG), but all cell lines deficient in a single EGFR ligand retained the ERK activation waves. Surprisingly, ERK activation waves were markedly suppressed, albeit incompletely, only when all four EGFR ligands were knocked out. Re-expression of the EGFR ligands revealed that all but HBEGF could restore the ERK activation waves. Aiming at complete elimination of the ERK activation waves, we further attempted to knockout NRG1, a ligand for ErbB3 and ErbB4, and found that NRG1-deficiency induced growth arrest in the absence of all four EGFR ligand genes. Collectively, these results showed that EGFR ligands exhibit remarkable redundancy in the propagation of ERK activation waves during collective cell migration.

APA, Harvard, Vancouver, ISO, and other styles

49

Hassanein, Anber Mahmoud Ahmed, and Inas Mohamed Ali Mahmoud. "Essential factors for in vitro regeneration of rose and a protocol for plant regeneration from leaves." Horticultural Science 45, No. 2 (June 4, 2018): 83–91. http://dx.doi.org/10.17221/12/2017-hortsci.

Full text

Abstract:

In vitro propagation of Rosa hybrida, L. cv. ‘Eiffel Tower’ was improved by the addition of thidiazuron (TDZ) and silver nitrate (AgNo3) to the culture medium. The combination of auxin and cytokinins was indispensable for inducing response from leaf discs. Maintaining cultures under dark was better than light for callus formation and quality. The source of explants was vital in the regeneration process wherein situ explants produced callus while, in vitro explants regenerated somatic embryos and shoots. Gibberellic acid (GA3) had a favorable effect where in vitro explants showed somatic embryogenesis with no shoots on media containing TDZ however, 37% of explants regenerated shoots directly on medium containing GA3. The presence of benzyl adenine (BA) was essential for shoot elongation, and indole butyric acid (IBA) was better than indole acetic acid (IAA) for rooting. The optimum conditions produced rooted plants from leaf discs within ten weeks. The reported results clarify factors controlling in vitro regeneration of R. hybrida, and provide a rapid protocol allowing further improvements of rose.

APA, Harvard, Vancouver, ISO, and other styles

50

ZOU, FENG, JAMES K. WILLSON, ZHAO ZHANG, and WEILI WU. "FAST INFORMATION PROPAGATION IN SOCIAL NETWORKS." Discrete Mathematics, Algorithms and Applications 02, no. 01 (March 2010): 125–41. http://dx.doi.org/10.1142/s1793830910000528.

Full text

Abstract:

Social networks are attracting more attention from both industry and academia. Prior works on social networks focus on analyzing their roles in information propagation and decision making. However, few of these works consider the latency of information propagation, which is an essential issue especially in time-critical scenarios in social networks. In this paper, we introduce a new problem called FAST INFORMATION PROPAGATION PROBLEM, which is an optimization problem to identify the minimum set of influential nodes that could influence the whole network within a given latency bound d. We show our complexity result on this problem in the deterministic threshold models and present a greedy hill-climbing algorithm as the solution. For the d = 1 case, we prove that under the majority threshold model, this approximation algorithm has a performance ratio of H(Δ + 1) - 1 + ⌈ Δ/2⌉. Extensive experiments are conducted on a large collaboration network and the results show that our approximation algorithm outperforms the node-selection heuristics, which utilize the well-known approaches based on the node centrality in the social network analysis.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Roses Propagation'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles