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Sample records for boll abscission rate

  1. Verde plant bug (Hemiptera: Miridae) feeding injury to cotton bolls characterized by boll age, size, and damage ratings.

    Science.gov (United States)

    Armstrong, J Scott; Brewer, Michael J; Parker, Roy D; Adamczyk, J J

    2013-02-01

    The verde plant bug, Creontiades signatus (Distant), has been present in south Texas for several years but has more recently been documented as an economic threat to cultivated cotton, (Gossypium hirsutum L. Our studies over 2 yr (2009 and 2010) and two locations (Weslaco and Corpus Christi, TX) investigated feeding-injury of the verde plant bug to a range of cotton boll age classes defined by boll diameter and accumulated degree-days (anthesis to the time of infesting) for first-position cotton bolls infested with the plant bugs. The most detrimental damage to younger cotton holls from verde plant bug feeding was boll abscission. Cotton bolls verde plant bug injured bolls compared with the controls up to 162 ACDD or a mean boll diameter 2.0 cm. Cotton seed weights were significantly reduced up to 179 ACDD or a boll diameter of 2.0 cm at Weslaco in 2009, and up to 317 ACDD or boll diameter 2.6 cm for Weslaco in 2010 when compared with the noninfested controls. Lint weight per cotton boll for infested and noninfested bolls was significantly reduced up to 262 ACDD or boll diameter 2.5 for Corpus Christi in 2010 and up to 288 ACCD or boll diameter 2.6 cm for Weslaco, TX, in 2010. Damage ratings (dependant variable) regressed against infested and noninfested seed-cotton weights showed that in every instance, the infested cotton bolls had a strong and significant relationship with damage ratings for all age classes of bolls. Damage ratings for the infested cotton bolls that did not abscise by harvest showed visual signs of verde plant bug feeding injury and the subsequent development ofboll rot; however, these two forms of injury causing lint and seed mass loss are hard to differentiate from open or boll-locked cotton bolls. Based on the results of both lint and seed loss over 2 yr and four studies cotton bolls should be protected up to approximately 300 ACDD or a boll diameter of 2.5 cm. This equilibrates to bolls that are 12-14 d of age dependent upon daily maximum

  2. Verde plant bug (Hemiptera: Miridae) feeding injury to cotton bolls charcterized by boll age, size and damage ratings

    Science.gov (United States)

    Our studies over 2 years (2009 and 2010) and 2 locations (Weslaco and Corpus Christi, TX) investigated the relationship of feeding-injury of the verde plant bug, Creontiades signatus Distant, to a range of cotton boll age classes further defined by boll diameter and accumulated degree-days (anthesis...

  3. Mechanical damage in cotton buds caused by the boll weevil

    Directory of Open Access Journals (Sweden)

    Santos Roseane Cavalcanti

    2003-01-01

    Full Text Available The boll weevil (Anthonomus grandis Boheman causes high levels of bud abscission in cotton plants due to feeding or oviposition punctures. It has been reported that abscission is mainly due to enzymes present in the insect's saliva, but mechanical damage could also contribute to square abscission. The objective of this paper was to undertake an analysis of the morphological damages caused by the insect in cotton squares using microscopy. Anthers and ovules are the main target of boll weevil feeding. The process initiates by perforation of young sepal and petal tissues and proceeds with subsequent alimentation on stamen and ovary leading to abscission of floral structures.

  4. Reducing boll weevil populations by clipping terminal buds and removing abscised fruiting bodies

    Science.gov (United States)

    The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae) punctures cotton squares and young bolls during feeding and oviposition, causing abscission of flower buds (squares) in the instance of oviposition. Fallen squares are a source of next generation adult boll weevils that...

  5. Stink Bug Feeding Induces Fluorescence in Developing Cotton Bolls

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    Toews Michael D

    2011-08-01

    Full Text Available Abstract Background Stink bugs (Hemiptera: Pentatomidae comprise a critically important insect pest complex affecting 12 major crops worldwide including cotton. In the US, stink bug damage to developing cotton bolls causes boll abscission, lint staining, reduced fiber quality, and reduced yields with estimated losses ranging from 10 to 60 million dollars annually. Unfortunately, scouting for stink bug damage in the field is laborious and excessively time consuming. To improve scouting accuracy and efficiency, we investigated fluorescence changes in cotton boll tissues as a result of stink bug feeding. Results Fluorescent imaging under long-wave ultraviolet light showed that stink bug-damaged lint, the inner carpal wall, and the outside of the boll emitted strong blue-green fluorescence in a circular region near the puncture wound, whereas undamaged tissue emissions occurred at different wavelengths; the much weaker emission of undamaged tissue was dominated by chlorophyll fluorescence. We further characterized the optimum emission and excitation spectra to distinguish between stink bug damaged bolls from undamaged bolls. Conclusions The observed characteristic fluorescence peaks associated with stink bug damage give rise to a fluorescence-based method to rapidly distinguish between undamaged and stink bug damaged cotton bolls. Based on the fluorescent fingerprint, we envision a fluorescence reflectance imaging or a fluorescence ratiometric device to assist pest management professionals with rapidly determining the extent of stink bug damage in a cotton field.

  6. Endogenous auxin regulates the sensitivity of Dendrobium (cv. Miss Teen) flower pedicel abscission to ethylene

    NARCIS (Netherlands)

    Rungruchkanont, K.; Ketsa, S.; Chatchawankanphanich, O.; Doorn, van W.G.

    2007-01-01

    Dendrobium flower buds and flowers have an abscission zone at the base of the pedicel (flower stalk). Ethylene treatment of cv. Miss Teen inflorescences induced high rates of abscission in flower buds but did not affect abscission once the flowers had opened. It is not known if auxin is a regulator

  7. Relationships of abscised cotton fruit to boll weevil (Coleoptera: Curculionidae) feeding, oviposition, and development.

    Science.gov (United States)

    Showler, Allan T

    2008-02-01

    Abscised cotton, Gossypium hirsutum L., fruit in field plots planted at different times were examined to assess adult boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), use of squares and bolls during 2002 and 2003 in the Lower Rio Grande Valley of Texas. Although boll abscission is not necessarily related to infestation, generally more bolls abscised than squares and abundances of fallen bolls were not related to the planting date treatments. During 2003, fallen squares were most abundant in the late-planted treatment. Although large squares (5.5-8-mm-diameter) on the plant are preferred for boll weevil oviposition, diameter of abscised squares is not a reliable measurement because of shrinkage resulting from desiccation and larval feeding. Fallen feeding-punctured squares and bolls were most abundant in late plantings but differences between fallen feeding-punctured squares versus fallen feeding-punctured bolls were found in only one treatment in 2003. During the same year, fallen oviposition-punctured squares were more numerous in the late-planted treatment than in the earlier treatments. Treatment effects were not found on numbers of oviposition-punctured bolls, but fallen oviposition-punctured squares were more common than bolls in the late-planted treatment compared with earlier treatments each year. Dead weevil eggs, larvae, and pupae inside fallen fruit were few and planting date treatment effects were not detected. Living third instars and pupae were more abundant in fallen squares of the late-planted treatment than in the earlier treatments and bolls of all three treatments. This study shows that fallen squares in late-planted cotton contribute more to adult boll weevil populations than bolls, or squares of earlier plantings.

  8. Ethephon As a Potential Abscission Agent for Table Grapes: Effects on Pre-Harvest Abscission, Fruit Quality, and Residue

    Science.gov (United States)

    Ferrara, Giuseppe; Mazzeo, Andrea; Matarrese, Angela M. S.; Pacucci, Carmela; Trani, Antonio; Fidelibus, Matthew W.; Gambacorta, Giuseppe

    2016-01-01

    Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color, and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but pre-harvest abscission was much lower (≅49%) in Crimson Seedless compared to Thompson Seedless. Treated fruits were slightly darker than non-treated fruits, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits. PMID:27303407

  9. Polyamine-Induced Rapid Root Abscission in Azolla pinnata.

    Science.gov (United States)

    Gurung, Sushma; Cohen, Michael F; Fukuto, Jon; Yamasaki, Hideo

    2012-01-01

    Floating ferns of the genus Azolla detach their roots under stress conditions, a unique adaptive response termed rapid root abscission. We found that Azolla pinnata plants exhibited dose-dependent rapid root abscission in response to the polyamines spermidine and spermine after a substantial time lag (>20 min). The duration of the time lag decreased in response to high pH and high temperature whereas high light intensity increased the time lag and markedly lowered the rate of abscission. The oxidation products of polyamines, 1,3-diaminopropane, β-alanine and hydrogen peroxide all failed to initiate root abscission, and hydroxyethyl hydrazine, an inhibitor of polyamine oxidase, did not inhibit spermine-induced root abscission. Exposure of A. pinnata to the polyamines did not result in detectable release of NO and did not affect nitrite-dependent NO production. The finding of polyamine-induced rapid root abscission provides a facile assay for further study of the mode of action of polyamines in plant stress responses.

  10. Boll weevil (Coleoptera: Curculionidae) response to and volatilization rates of grandlure when combined with varying doses of eugenol in the extended-life pheromone lure.

    Science.gov (United States)

    Armstrong, J S

    2010-04-01

    Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), trapping and pheromone quantitative analysis of extended-life pheromone lures manufactured with 0, 10, 20, and 30 mg of eugenol was conducted in the Rio Grande Valley of Texas under spring and summer conditions. Boll weevils responded positively to eugenol on one of 12 trapping weeks when densities were high, but when densities were low (30 degrees C, accumulative grandlure loss per week may be too high, leaving too little residual grandlure to effectively attract boll weevils at the end of 3 wk of trapping. Eugenol plays no role in reserving or encouraging the release of grandlure, or in increasing boll weevil captures when boll weevil densities are low.

  11. Saxl and Boll

    Directory of Open Access Journals (Sweden)

    Dorothea McEwan

    2011-12-01

    Full Text Available We know of Aby Warburg being Fritz Saxl’s mentor. What is less known is that Saxl had a second mentor, equally important for his research development, Franz Boll, the celebrated classical philologist. The article charts Boll’s involvement in Saxl’s research activities upon leaving university.

  12. Do boll weevils really diapause?

    Science.gov (United States)

    Boll weevil, Anthonomus grandis grandis Boheman, diapause has been poorly understood since the term was first used 50 yrs ago to describe the pest’s winter dormancy in temperate regions. This literature-based study found that low temperature and changes in photoperiod are the boll weevil diapause-i...

  13. Understanding the physiology of postharvest needle abscission in balsam fir

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    Mason Thane Macdonald

    2015-11-01

    Full Text Available Balsam fir (Abies balsamea trees are commonly used as a specialty horticultural species for Christmas trees and associated greenery in eastern Canada and United States. Postharvest needle abscission has always been a problem, but is becoming an even bigger challenge in recent years presumably due to increased autumn temperatures and earlier harvesting practices. An increased understanding of postharvest abscission physiology in balsam fir may benefit the Christmas tree industry while simultaneously advancing our knowledge in senescence and abscission of conifers in general. Our paper describes the dynamics of needle abscission in balsam fir while identifying key factors that modify abscission patterns. Concepts such as genotypic abscission resistance, nutrition, environmental factors, and postharvest changes in water conductance and hormone evolution are discussed as they relate to our understanding of the balsam fir abscission physiology. Our paper ultimately proposes a pathway for needle abscission via ethylene and also suggests other potential alternative pathways based on our current understanding.

  14. Parasitoids of boll weevil Anthonomus grandis and resident predators in kaolin-treated cotton

    Directory of Open Access Journals (Sweden)

    Roberta Leme Santos

    2013-12-01

    Full Text Available Simultaneous use of control methods is essential to reach success in managing arthropod pests. The current study investigated the effect of kaolin application on resident predators in the cotton plant canopy and parasitism of boll weevil on abscised squares in the field, and parasitism of boll weevil in the laboratory. Predators Araneae, Formicidae, Chrysopidae, and Coccinellidae showed similar seasonal densities for kaolin-treated and untreated cotton fields as well as the emergence rate of the parasitoids Bracon vulgaris Ashmead (Hymenoptera: Braconidae and Catolaccus grandis Burks (Hymenoptera: Pteromalidae from abscised field-collected structures. Under laboratory conditions, the parasitism of boll weevil larvae infesting squares was similar when treated and untreated squares with kaolin were offered to the parasitoid under free choice test. Therefore, the results show that spraying cotton fields with kaolin does not affect the natural biological control by parasitoids of boll weevil and pink bollworm and resident predators naturally occurring in cotton fields.

  15. Boll weevil invasion process in Argentina

    Science.gov (United States)

    The boll weevil, Anthonomus grandis grandis Boheman, is the most destructive cotton pest in the Western Hemisphere. In 1993, the pest was reported in Argentina, and in 1994 boll weevils were captured in cotton fields in the Formosa Province on the border between Argentina and Paraguay. The pest ha...

  16. High floral bud abscission and lack of open flower abscission in Dendrobium cv. Miss Teen: rapid reduction of ethylene sensitivity in the abscission zone

    NARCIS (Netherlands)

    Bunya-atichart, K.; Ketsa, S.; Doorn, van W.G.

    2006-01-01

    We studied the abscission of floral buds and open flowers in cut Dendrobium inflorescences. Abscission of floral buds was high and sensitive to ethylene in all cultivars studied. Many open flowers abscised in most cultivars, but cv. Willie exhibited only small amount of floral fall and cv. Miss Teen

  17. [Effects of drought and waterlogging on carbohydrate contents of cotton boll and its relationship with boll biomass accumulation at the flowering and bolling stage].

    Science.gov (United States)

    Yang, Chang-Qin; Liu, Jing-Ran; Zhang, Guo-Wei; Liu, Rui-Xian; Zhou, Zhi-Guo

    2014-08-01

    Cotton cultivar NuCOTN 33B was planted in isolated pools treated with drought or waterlogging for 7 or 14 d to explore their effects on cotton boll carbohydrate content and its relationship with the biomass accumulation. The results showed that the drought treatment reduced the carbohydrate content of cotton boll shell on middle fruit branches, but had a weak effect on cotton boll shells on lower fruit branches. Soluble sugar, starch and sucrose contents of cotton boll shell on upper fruit branches under the drought condition and on whole plant branches under waterlogging treatment changed similarly, namely, the soluble sugar and starch content increased, while the sucrose content went down firstly and then increased later, which indicated that the exportation of sucrose from boll shell was inhibited and became worse with the increase of waterlogging duration. Compared with the boll shell, the carbohydrate contents of cotton seed were less affected by the drought and waterlogging treatments at the flowering and bolling stage. Under the treatments of drought and 7 d-waterlogging, the biomass accumulation of cotton bolls on the middle fruit branches initiated earlier but lasted less days, and the maximum speed at lower and upper fruit branches reduced, while the treatment of waterlogging for 14 d caused the decline of maximum speed of biomass accumulation of bolls on whole branches. On the other side, the correlation analysis showed the significant positive relationships among the boll biomass, the maximum speed and the contents of soluble sugar and sucrose in the boll shell respectively. In conclusion, the treatment of drought and waterlogging at the flowering and bolling stage retarded the outward transportation of sucrose from cotton bolls, changed the boll biomass accumulation characteristics, and therefore were detected as the important cause of cotton boll total biomass reduction.

  18. Flower abscission in Vitis vinifera L. triggered by gibberellic acid and shade discloses differences in the underlying metabolic pathways

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    Sara eDomingos

    2015-06-01

    Full Text Available Understanding abscission is both a biological and an agronomic challenge. Flower abscission induced independently by shade and gibberellic acid (GAc sprays was monitored in grapevine (Vitis vinifera L. growing under a soilless greenhouse system during two seasonal growing conditions, in an early and late production cycle. Physiological and metabolic changes triggered by each of the two distinct stimuli were determined. Environmental conditions exerted a significant effect on fruit set as showed by the higher natural drop rate recorded in the late production cycle with respect to the early cycle. Shade and GAc treatments increased the percentage of flower drop compared to the control, and at a similar degree, during the late production cycle. The reduction of leaf gas exchanges under shade conditions was not observed in GAc treated vines. The metabolic profile assessed in samples collected during the late cycle differently affected primary and secondary metabolisms and showed that most of the treatment-resulting variations occurred in opposite trends in inflorescences unbalanced in either hormonal or energy deficit abscission-inducing signals. Particularly concerning carbohydrates metabolism, sucrose, glucose, tricarboxylic acid (TCA metabolites and intermediates of the raffinose family oligosaccharides pathway were lower in shaded and higher in GAc samples. Altered oxidative stress remediation mechanisms and indolacetic acid (IAA concentration were identified as abscission signatures common to both stimuli. According to the global analysis performed, we report that grape flower abscission mechanisms triggered by GAc application and C-starvation are not based on the same metabolic pathways.

  19. Growth and abscission of avocado fruits (Persea americana Mill. cv. Fuerte

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    Rodolfo B.Muñoz Perez

    2013-12-01

    Full Text Available In a commerical orchard of 18-year-old trees, 1250 fruits were chosen for observation. The majority of them abscised during the first weeks after anthesis. Afterwards, the abscission gradually descreased, however, in the meantime three additional waves of more intensive shedding occurred which were best visible when the Relative Abscission Rate (RAR was calculated. The peaks in the RAR curve were preceded by a decrease in the Relative Growth Rate (RGR of persistent fruits, which suggests that nutritional or other stresses occurred in the whole branch. In the period from May 15th to July 15th, predominantly the smaller fruits were abscised, later on, however, fruits of the same size as the persistent ones were shed. The formula for calculating RAR and RAR is shortly discussed.

  20. The influence of abscisic acid on the ethylene biosynthesis pathway in the functioning of the flower abscission zone in Lupinus luteus.

    Science.gov (United States)

    Wilmowicz, Emilia; Frankowski, Kamil; Kućko, Agata; Świdziński, Michał; de Dios Alché, Juan; Nowakowska, Anna; Kopcewicz, Jan

    2016-11-01

    Flower abscission is a highly regulated developmental process activated in response to exogenous (e.g. changing environmental conditions) and endogenous stimuli (e.g. phytohormones). Ethylene (ET) and abscisic acid (ABA) are very effective stimulators of flower abortion in Lupinus luteus, which is a widely cultivated species in Poland, Australia and Mediterranean countries. In this paper, we show that artificial activation of abscission by flower removal caused an accumulation of ABA in the abscission zone (AZ). Moreover, the blocking of that phytohormone's biosynthesis by NDGA (nordihydroguaiaretic acid) decreased the number of abscised flowers. However, the application of NBD - an inhibitor of ET action - reversed the stimulatory effect of ABA on flower abscission, indicating that ABA itself is not sufficient to turn on the organ separation. Our analysis revealed that exogenous ABA significantly accelerated the transcriptional activity of the ET biosynthesis genes ACC synthase (LlACS) and oxidase (LlACO), and moreover, strongly increased the level of 1-aminocyclopropane-1-carboxylic acid (ACC) - ET precursor, which was specifically localized within AZ cells. We cannot exclude the possibility that ABA mediates flower abscission processes by enhancing the ET biosynthesis rate. The findings of our study will contribute to the overall basic knowledge on the phytohormone-regulated generative organs abscission in L. luteus. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. Understanding the Physiology of Postharvest Needle Abscission in Balsam Fir

    OpenAIRE

    Lada, Rajasekaran R.; MacDonald, Mason T.

    2015-01-01

    Balsam fir (Abies balsamea) trees are commonly used as a specialty horticultural species for Christmas trees and associated greenery in eastern Canada and United States. Postharvest needle abscission has always been a problem, but is becoming an even bigger challenge in recent years presumably due to increased autumn temperatures and earlier harvesting practices. An increased understanding of postharvest abscission physiology in balsam fir may benefit the Christmas tree industry while simulta...

  2. Ethylene: Role in Fruit Abscission and Dehiscence Processes 12

    Science.gov (United States)

    Lipe, John A.; Morgan, Page W.

    1972-01-01

    Two peaks of ethylene production occur during the development of cotton fruitz (Gossypium hirsutum L.). These periods precede the occurrence of young fruit shedding and mature fruit dehiscence, both of which are abscission phenomena and the latter is generally assumed to be part of the total ripening process. Detailed study of the dehiscence process revealed that ethylene production of individual, attached cotton fruits goes through a rising, cyclic pattern which reaches a maximum prior to dehiscence. With detached pecan fruits (Carya illinoensis [Wang.] K. Koch), ethylene production measured on alternate days rose above 1 microliter per kilogram fresh weight per hour before dehiscence began and reached a peak several days prior to complete dehiscence. Ethylene production by cotton and pecan fruits was measured just prior to dehiscence and then the internal concentration of the gas near the center of the fruit was determined. From these data a ratio of production rate to internal concentration was determined which allowed calculation of the approximate ethylene concentration in the intact fruit prior to dehiscence and selection of appropriate levels to apply to fruits. Ethylene at 10 microliters per liter of air appears to saturate dehiscence of cotton, pecan, and okra (Hibiscus esculentus L.) fruits and the process is completed in 3 to 4 days. In all cases some hastening of dehiscence was observed with as little as 0.1 microliter of exogenous ethylene per liter of air. The time required for response to different levels of ethylene was determined and compared to the time course of ethylene production and dehiscence. We concluded that internal levels of ethylene rose to dehiscence-stimulating levels a sufficience time before dehiscence for the gas to have initiated the process. Since our data and calculations indicate that enough ethylene is made a sufficient time before dehiscence, to account for the process, we propose that ethylene is one of the regulators of

  3. Ethylene: role in fruit abscission and dehiscence processes.

    Science.gov (United States)

    Lipe, J A; Morgan, P W

    1972-12-01

    Two peaks of ethylene production occur during the development of cotton fruitz (Gossypium hirsutum L.). These periods precede the occurrence of young fruit shedding and mature fruit dehiscence, both of which are abscission phenomena and the latter is generally assumed to be part of the total ripening process. Detailed study of the dehiscence process revealed that ethylene production of individual, attached cotton fruits goes through a rising, cyclic pattern which reaches a maximum prior to dehiscence. With detached pecan fruits (Carya illinoensis [Wang.] K. Koch), ethylene production measured on alternate days rose above 1 microliter per kilogram fresh weight per hour before dehiscence began and reached a peak several days prior to complete dehiscence. Ethylene production by cotton and pecan fruits was measured just prior to dehiscence and then the internal concentration of the gas near the center of the fruit was determined. From these data a ratio of production rate to internal concentration was determined which allowed calculation of the approximate ethylene concentration in the intact fruit prior to dehiscence and selection of appropriate levels to apply to fruits. Ethylene at 10 microliters per liter of air appears to saturate dehiscence of cotton, pecan, and okra (Hibiscus esculentus L.) fruits and the process is completed in 3 to 4 days. In all cases some hastening of dehiscence was observed with as little as 0.1 microliter of exogenous ethylene per liter of air. The time required for response to different levels of ethylene was determined and compared to the time course of ethylene production and dehiscence. We concluded that internal levels of ethylene rose to dehiscence-stimulating levels a sufficience time before dehiscence for the gas to have initiated the process. Since our data and calculations indicate that enough ethylene is made a sufficient time before dehiscence, to account for the process, we propose that ethylene is one of the regulators of

  4. [Effects of soil progressive drought during the flowering and boll-forming stage on gas exchange parameters and chlorophyll fluorescence characteristics of the subtending leaf to cotton boll].

    Science.gov (United States)

    Liu, Zhao-wei; Zhang, Pan; Wang, Rui; Kuai, Jie; Li, Lei; Wang, You-hua; Zhou, Zhi-guo

    2014-12-01

    To investigate the dynamic changes and response mechanisms of gas exchange parameters and fluorescence indices of the subtending leaf to cotton boll under soil progressive drought stress, pot experiments of the hybrid cotton No. 3 were conducted with soil relative water content (SRWC) (75 +/- 5)% as control group, SRWC (60 +/- 5)% and SRWC (45 +/- 5)% as experimental groups dealt with progressive drought for 50 days. Results showed that, the net photosynthetic rate (Pn), stomatal conductance (g(s)) and leaf intercellular CO2 concentration (Ci) decreased while Ls increased under SRWC (60 +/- 5)% for 0-21 days. Furthermore, there was no significant change in chlorophyll fluorescence indices. This indicated that stomatal limitation was the main reason for the reduction of photosynthesis of cotton. In addition, when drought for 21-49 days under SRWC (60 +/- 5)%, Pn kept decreasing, while Ci began to increase and Ls began to decrease. Potential photochemical efficiency (Fv/Fm), quantum yield of photo system II (phi(PSI)) and photochemical quenching coefficient (q(P)) reduced significantly, but non-photochemical quenching coefficient (NPQ) first rose then decreased. Thus, nonstomatal limitation was the main reason why the photosynthesis of cotton reduced. Photosynthetic organization and photosynthetic enzyme system were destroyed, boll setting intensity reduced and the number of boll and yield reduced significantly. Drought for 0-14 days under SRWC (45 +/- 5)% treatment led to sharp decrease in Pn, g(s) and Ci, whereas Ls obviously increased. There was no significant change in Fv/Fm, phi(PSII), q(P), indicating stomatal limitation was the main reason why the photosynthesis of cotton reduced. Pn decreased slowly, while Ci began to rise and Ls began to decline under SRWC (45 +/- 5)% treatment for 14-49 days. Fv/Fm, phi(PSII), q(P) decreased while NPQ rose first then declined, which indicated that nonstomatal limitation worked to reduce the cotton photosynthetic performance

  5. Response of successive three generations of cotton bollworm, Helicoverpa armigera (Hübner), fed on cotton bolls, under elevated CO2

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Hübner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.

  6. Detecting cotton boll rot with an electronic nose

    Science.gov (United States)

    South Carolina Boll Rot is an emerging disease of cotton, Gossypium hirsutum L., caused by the opportunistic bacteria, Pantoea agglomerans (Ewing and Fife). Unlike typical fungal diseases, bolls infected with P. agglomerans continue to appear normal externally, complicating early and rapid detectio...

  7. Verde plant bug associatioin with boll damage including cotton boll rot and potential in-season indicators of damage

    Science.gov (United States)

    Cotton along the Gulf Coast of south Texas has experienced loss from cotton boll rot especially during the last 10 to 15 years, and stink bugs and plant bugs (Hemiptera: Pentatomidae and Miridae) that feed on cotton bolls have been suspected in introducing the disease. A replicated grower field surv...

  8. Studies on reproductive abscission and seed yield of mungbean ...

    African Journals Online (AJOL)

    A field study was conducted on the Research and Experimental Farm of the University of Agriculture Makurdi (7o41'N, 08o37'N, and 400 m above mean sea level), Nigeria, in 2001 and 2002 to examine the abscission of reproductive structures in mungbean (Vigna radiata). Four exotic cultivars (VC 2768A, VC 1178A, VC ...

  9. Breakdown of middle lamella pectin by (●) OH during rapid abscission in Azolla.

    Science.gov (United States)

    Yamada, Yoshiya; Koibuchi, Mizuki; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

    2015-08-01

    Azolla, a small water fern, abscises its roots and branches within 30 min upon treatment with various stresses. This study was conducted to test whether, in the rapid abscission that occurs in Azolla, breakdown of wall components of abscission zone cells by (●) OH is involved. Experimentally generated (●) OH caused the rapid separation of abscission zone cells from detached roots and the rapid shedding of roots from whole plants. Electron microscopic observations revealed that (●) OH rapidly and selectively dissolved a well-developed middle lamella between abscission zone cells and resultantly caused rapid cell separation and shedding. Treatment of abscission zones of Impatiens leaf petiole with (●) OH also accelerated the separation of abscission zone cells. However, compared with that of Azolla roots, accelerative effects in Impatiens were weak. A large amount of (●) OH was cytochemically detected in abscission zone cells both of Azolla roots and of Impatiens leaf petioles. These results suggest that (●) OH is involved in the cell separation process not only in the rapid abscission in Azolla but also in the abscission of Impatiens. However, for rapid abscission to occur, a well-developed middle lamella, a unique structure, which is sensitive to the attack of (●) OH, might be needed. © 2015 John Wiley & Sons Ltd.

  10. Toxicity to cotton boll weevil Anthonomus grandis of a trypsin inhibitor from chickpea seeds.

    Science.gov (United States)

    de P G Gomes, Angélica; Dias, Simoni C; Bloch, Carlos; Melo, Francislete R; Furtado, José R; Monnerat, Rose G; Grossi-de-Sá, Maria F; Franco, Octávio L

    2005-02-01

    Cotton (Gossypium hirsutum L.) is an important agricultural commodity, which is attacked by several pests such as the cotton boll weevil Anthonomus grandis. Adult A. grandis feed on fruits and leaf petioles, reducing drastically the crop production. The predominance of boll weevil digestive serine proteinases has motivated inhibitor screenings in order to discover new ones with the capability to reduce the digestion process. The present study describes a novel proteinase inhibitor from chickpea seeds (Cicer arietinum L.) and its effects against A. grandis. This inhibitor, named CaTI, was purified by using affinity Red-Sepharose Cl-6B chromatography, followed by reversed-phase HPLC (Vydac C18-TP). SDS-PAGE and MALDI-TOF analyses, showed a unique monomeric protein with a mass of 12,877 Da. Purified CaTI showed significant inhibitory activity against larval cotton boll weevil serine proteinases (78%) and against bovine pancreatic trypsin (73%), when analyzed by fluorimetric assays. Although the molecular mass of CaTI corresponded to alpha-amylase/trypsin bifunctional inhibitors masses, no inhibitory activity against insect and mammalian alpha-amylases was observed. In order to observe CaTI in vivo effects, an inhibitor rich fraction was added to an artificial diet at different concentrations. At 1.5% (w/w), CaTI caused severe development delay, several deformities and a mortality rate of approximately 45%. These results suggested that CaTI could be useful in the production of transgenic cotton plants with enhanced resistance toward cotton boll weevil.

  11. ALIX and ESCRT-III coordinately control cytokinetic abscission during germline stem cell division in vivo.

    Directory of Open Access Journals (Sweden)

    Åsmund H Eikenes

    2015-01-01

    Full Text Available Abscission is the final step of cytokinesis that involves the cleavage of the intercellular bridge connecting the two daughter cells. Recent studies have given novel insight into the spatiotemporal regulation and molecular mechanisms controlling abscission in cultured yeast and human cells. The mechanisms of abscission in living metazoan tissues are however not well understood. Here we show that ALIX and the ESCRT-III component Shrub are required for completion of abscission during Drosophila female germline stem cell (fGSC division. Loss of ALIX or Shrub function in fGSCs leads to delayed abscission and the consequent formation of stem cysts in which chains of daughter cells remain interconnected to the fGSC via midbody rings and fusome. We demonstrate that ALIX and Shrub interact and that they co-localize at midbody rings and midbodies during cytokinetic abscission in fGSCs. Mechanistically, we show that the direct interaction between ALIX and Shrub is required to ensure cytokinesis completion with normal kinetics in fGSCs. We conclude that ALIX and ESCRT-III coordinately control abscission in Drosophila fGSCs and that their complex formation is required for accurate abscission timing in GSCs in vivo.

  12. Forensic pollen geolocation techniques used to identify the origin of boll weevil reinfestation

    Science.gov (United States)

    The boll weevil, Anthonomus grandis, entered the United States of America in the early 20th century and became a major pest in cotton, Gossypium spp. Shortly after the passage of Tropical Storm Erin on 16 August 2007 through the South Texas/Winter Garden boll weevil eradication zone, over 150 boll ...

  13. Boll weevil eradication: a model for sea lamprey control?

    Science.gov (United States)

    Smith, James W.; Swink, William D.

    2003-01-01

    Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should

  14. Effects of insecticides and defoliants applied alone and in combination for control of overwintering boll weevil (Anthonomus grandis; Coleoptera: Curculionidae)--laboratory and field studies.

    Science.gov (United States)

    Greenberg, Shoil M; Sappington, Thomas W; Elzen, Gary W; Norman, John W; Sparks, Alton N

    2004-09-01

    In laboratory, greenhouse and field tests, we determined the effects of combining full rates of the defoliants tribufos and thidiazuron and the herbicide thifensulfuron-methyl with half rates of the insecticides lambda-cyhalothrin or azinphos-methyl, and the combination of tribufos and thidiazuron, both in half rates, on mortality of the boll weevil, Anthonomus grandis grandis Boheman and on the quality of defoliation. Tribufos, 0.47 kg ha(-1) and tribufos, 0.235 kg ha(-1) + thidiazuron, 0.125 kg ha(-1) exhibited a slightly toxic effect to boll weevil, while tribufos, 0.47 kg ha(-1) + lambda-cyhalothrin, 0.019 kg ha(-1), tribufos, 0.47 kg ha(-1) + azinphos-methyl, 0.14 kg ha(-1), and tribufos, 0.235 kg ha(-1) + thidiazuron, 0.125 kg ha(-1) + azinphos-methyl, 0.14 kg ha(-l), provided control of boll weevil as good as or better than full-rate azinphos-methyl or lambda-cyhalothrin alone owing to synergistic effects. Thidiazuron or thifensulfuron-methyl alone or in combination with insecticides did not affect boll weevil mortality. Treatment with tribufos + thidiazuron, both at half rate, significantly increased defoliation compared to full rates of tribufos or thidiazuron alone, and provided adequate defoliation for approximately the same cost per hectare.

  15. Visualizing Morphological Changes of Abscission Zone Cells in Arabidopsis by Scanning Electron Microscope.

    Science.gov (United States)

    Shi, Chun-Lin; Butenko, Melinka A

    2018-01-01

    Scanning electron microscope (SEM) is a type of electron microscope which produces detailed images of surface structures. It has been widely used in plants and animals to study cellular structures. Here, we describe a detailed protocol to prepare samples of floral abscission zones (AZs) for SEM, as well as further image analysis. We show that it is a powerful tool to detect morphologic changes at the cellular level during the course of abscission in wild-type plants and to establish the details of phenotypic alteration in abscission mutants.

  16. Activity of cell wall degrading glycanases in methyl jasmonate-induced leaf abscission in Kalanchoe blossfeldiana

    Directory of Open Access Journals (Sweden)

    Marian Saniewski

    2013-12-01

    Full Text Available It was found previously that methyl jasmonate (JA-Me induced leaf abscission in Kalanchoe blossfeldiana. In present studies it was shown that JA-Me markedly increased the total activities of cellulase, polygalacturonase, pectinase and xylanase in petioles, but did not affect activities of these enzymes in the blades and apical part of shoots of K. blossfeldiana. These results suggest that methyl jasmonate promotes the degradation of cell wall polysaccharides in the abscission zone and in this way induces leaf abscission in Kalanchoe blossfeldiana.

  17. Field evaluation of Bt cotton crop impact on nontarget pests: cotton aphid and boll weevil.

    Science.gov (United States)

    Sujii, E R; Togni, P H B; de A Ribeiro, P; de A Bernardes, T; Milane, P V G N; Paula, D P; Pires, C S S; Fontes, E M G

    2013-02-01

    Bt cotton plants expressing Cry1Ac protein have high specificity for the control of lepidopteran larvae. However, studies conducted in several countries have shown these plants have a differential impact on nontarget herbivores. The aim of this study was to compare the colonization rates and population abundance of the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) and the boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), in plots of Bt (Nuopal) and non-Bt cotton (Delta Opal) in an experimental field in Brasilia, DF, Brazil. No difference was observed in the preference and colonization by winged aphids to plants from the two treatments. There was no significant difference in abundance of wingless aphids or in the production of winged aphids between treatments. Apparently, the parameters that control factors such as fecundity, survival, and dispersal were similar on both Bt and non-Bt plants. Monitoring of plants for coccinellids, a specialist predator of aphids, and ants that act on the dispersal of aphids among plants showed no significant difference between Bt and non-Bt plants, supporting the inference above. Regarding the effect on boll weevil, there was also no significant difference between treatments in the total number of fruiting structures attacked in each plot, the percentage of fruiting structures attacked per plant or on the number of weevils emerging from fruits with boll weevil damage from egg-laying, when damaged fruit samples were held in the laboratory. Based on these results, we conclude that there is no impact of Bt cotton crop expressing Cry1Ac on the nontarget herbivores tested under field conditions.

  18. The conundrum of chemical boll weevil control in subtropical regions

    Science.gov (United States)

    The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a tropical Mesoamerican insect that invaded the United States in 1893, spreading across the Cotton Belt as the key pest of cotton and causing billions of dollars in yield losses and insecticide-based control efforts;...

  19. Activity of cell wall degrading glycanases in methyl jasmonate-induced leaf abscission in Kalanchoe blossfeldiana

    OpenAIRE

    Marian Saniewski; Ewa Gajewska; Henryk Urbanek

    2013-01-01

    It was found previously that methyl jasmonate (JA-Me) induced leaf abscission in Kalanchoe blossfeldiana. In present studies it was shown that JA-Me markedly increased the total activities of cellulase, polygalacturonase, pectinase and xylanase in petioles, but did not affect activities of these enzymes in the blades and apical part of shoots of K. blossfeldiana. These results suggest that methyl jasmonate promotes the degradation of cell wall polysaccharides in the abscission zone and in thi...

  20. Effect of 2.4-D exogenous application on the abscission and fruit growth in Sweet orange. var. Salustiana.

    Directory of Open Access Journals (Sweden)

    Rebolledo Alexander

    2012-04-01

    Full Text Available

    The effect of 2.4-D applications in full bloom on the abscission and fruit growth process was studied on sweet orange fruit in 20-year-old trees of Citrus sinensis (L. Osbeck cv. Salustiana with a high flowering level. Abscission was determined on the whole tree and on the leafy inflorescences. Growth variables of the fruit were characterized (diameter, fresh and dry weight. 2.4-D application (20 mg L-1, 3.6 L per tree increased the growth rate of the fruits and fruits size at maturity, however reduced the number of fruits which kept constant the yield at harvest. Differences between the diameter of the control fruits and the fruits treated with 2.4-D were observed during the early fruitlet development and until day 43 after anthesis. These differences increased with time following a linear relationship. For all the studied variables the diary increase level reaches the maximum by day 53, when the cell expansion of the vesicles starts.

  1. Karyotypic analysis of the cotton boll weevil, Anthonomus grandis Boheman.

    Science.gov (United States)

    McNally, L R; Beck, M L; Biggers, C J

    2000-01-01

    The diploid chromosome number of the cotton boll weevil, Anthonomus grandis Boheman, is 44. Both C- and N-banding techniques of mitotic cells demonstrated constitutive heterochromatin in the p arm of the eight largest chromosomes, the p arm of the X chromosome, and the centromeric region of autosomal groups A-D. Neither the y nor the group E autosomes appeared to contain constitutive heterochromatin. Supernumerary chromosomes were not found in the boll weevil. Restriction endonuclease banding of primary spermatocytes revealed a rod-shaped Xy tetrad in which the X and y were terminally associated. The p arm of the large, submetacentric X was C-band positive. While two of the autosomal tetrads were typically ring-shaped in primary spermatocytes, the remaining 19 autosomal tetrads were rod-shaped.

  2. Laboratory and field evaluation of sterile male boll weevil competitiveness

    International Nuclear Information System (INIS)

    McGovern, W.L.

    1976-01-01

    The production of pheromone by boll weevils, Anthonomus grandis Boheman, treated with 10,000 rad of CO-60 gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from the first day post-treatment. No direct correlation was found between production of pheromone and elimination of frass. Overwintered male boll weevils were found to produce small quantities of pheromone and the ratio of components was less attractive at the same concentration as the standard laboratory formulation of grandlure. Most healthy sterilized male weevils should be more attractive than overwintered males. Laboratory-reared sterilized male boll weevils can be as attractive to female weevils as overwintered field males. Weevils treated with busulfan (1,4-butanediol dimethanesulfonate) alone were more attractive than those treated with combinations of busulfan and hempa. In general, sterilization reduced the attractiveness of laboratory males by about 50 percent. Evidence is presented for the existence of ''super-males.''

  3. Tenancy, Marriage, and the Boll Weevil Infestation, 1892-1930.

    Science.gov (United States)

    Bloome, Deirdre; Feigenbaum, James; Muller, Christopher

    2017-06-01

    In the early twentieth century, the cotton-growing regions of the U.S. South were dominated by families of tenant farmers. Tenant farming created opportunities and incentives for prospective tenants to marry at young ages. These opportunities and incentives especially affected African Americans, who had few alternatives to working as tenants. Using complete-count Census of Population data from 1900-1930 and Census of Agriculture data from 1889-1929, we find that increases in tenancy over time increased the prevalence of marriage among young African Americans. We then study how marriage was affected by one of the most notorious disruptions to southern agriculture at the turn of the century: the boll weevil infestation of 1892-1922. Using historical Department of Agriculture maps, we show that the boll weevil's arrival reduced the share of farms worked by tenants as well as the share of African Americans who married at young ages. When the boll weevil infestation altered African Americans' opportunities and incentives to marry, the share of African Americans who married young fell accordingly. Our results provide new evidence about the effect of economic and political institutions on demographic transformations.

  4. Cotton harvest at 40% versus 75% boll-splitting on yield and economic return under standard and proactive boll weevil (Coleoptera: Curculionidae) spray regimes.

    Science.gov (United States)

    Showler, A T; Robinson, J R C

    2008-10-01

    The standard practice of two or three preemptive insecticide applications at the start of pinhead (1-2-mm-diameter) squaring followed by threshold-triggered (when 10% of randomly selected squares have oviposition punctures) insecticide applications for boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), control does not provide reliable protection of cotton, Gossypium hirsutum L., lint production. This study, conducted during 2004 and 2005, showed that three to six fewer spray applications in a "proactive" approach, in which spraying began at the start of large (5.5-8-mm-diameter) square formation and continued at approximately 7-d intervals while large squares were abundant, resulted in fewer infested squares and 1.4- to 1.7-fold more lint than the standard treatment. Fewer sprays and increased yield made proactive spraying significantly more profitable than the standard approach, which resulted in relatively low or negative economic returns. Harvest at 75% boll-split in the proactive spray regime of 2005 resulted in four-fold greater economic return than cotton harvested at 40% boll-split because of improved protection of large squares and the elimination of late-season sprays inherent to standard spray regime despite the cost of an extra irrigation in the 75% boll-split treatments. The earlier, 40% harvest trigger does not avoid high late-season boll weevil pressure, which exerts less impact on bolls, the predominant form of fruiting body at that time, than on squares. Proactive spraying and harvest timing are based on an important relationship between nutrition, boll weevil reproduction, and economic inputs; therefore, the tactic of combining proaction with harvest at 75% boll-split is applicable where boll weevils are problematic regardless of climate or region, or whether an eradication program is ongoing.

  5. Comparative transcriptional survey between laser-microdissected cells from laminar abscission zone and petiolar cortical tissue during ethylene-promoted abscission in citrus leaves

    Directory of Open Access Journals (Sweden)

    Tadeo Francisco R

    2009-10-01

    Full Text Available Abstract Background Abscission is the cell separation process by which plants are able to shed organs. It has a great impact on the yield of most crop plants. At the same time, the process itself also constitutes an excellent model to study cell separation processes, since it occurs in concrete areas known as abscission zones (AZs which are composed of a specific cell type. However, molecular approaches are generally hampered by the limited area and cell number constituting the AZ. Therefore, detailed studies at the resolution of cell type are of great relevance in order to accurately describe the process and to identify potential candidate genes for biotechnological applications. Results Efficient protocols for the isolation of specific citrus cell types, namely laminar abscission zone (LAZ and petiolar cortical (Pet cells based on laser capture microdissection (LCM and for RNA microextraction and amplification have been developed. A comparative transcriptome analysis between LAZ and Pet from citrus leaf explants subjected to an in-vitro 24 h ethylene treatment was performed utilising microarray hybridization and analysis. Our analyses of gene functional classes differentially represented in ethylene-treated LAZ revealed an activation program dominated by the expression of genes associated with protein synthesis, protein fate, cell type differentiation, development and transcription. The extensive repertoire of genes associated with cell wall biosynthesis and metabolism strongly suggests that LAZ layers activate both catabolic and anabolic wall modification pathways during the abscission program. In addition, over-representation of particular members of different transcription factor families suggests important roles for these genes in the differentiation of the effective cell separation layer within the many layers contained in the citrus LAZ. Preferential expression of stress-related and defensive genes in Pet reveals that this tissue is

  6. Evaluation of the Boll Weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) suppression program in the state of Goiás, Brazil.

    Science.gov (United States)

    de Lima, I S; Degrande, P E; Miranda, J E; dos Santos, W J

    2013-02-01

    The boll weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) is the most important cotton pest in Brazil. A large-scale field-testing of a Boll Weevil Suppression Program (BWSP) was implemented to assess its technical and operational feasibility for boll weevil suppression in the state of Goiás, Brazil. The pilot plan focused on 3,608 ha of cotton during the 2006/2007 and 6,011 ha in the 2007/2008 growing seasons; the areas were divided into four inner zones with an outer buffer zone. We analyzed data on boll weevil captures using pheromone traps installed in the BWSP fields, on the detection of the first insect and the first damaged floral bud, greatest damage, and number of insecticide applications. The nonparametric Mann-Whitney U test was used to evaluate the differences between presuppression and suppression years. Fourteen pheromone-baited trapping evaluations were used to compare the weevil populations from 2006/2007 and 2007/2008 growing seasons. The BWSP regime reduced in-season boll weevil captures from 15- to 500-fold compared to presuppression levels in the preceding year. The low capture rates were related to delays in infestation and damage by weevils. The smaller population size measured by trapping and field monitoring reduced the number of required insecticide treatments. The BWSP strategy was efficient in suppressing populations of this pest and is a viable program for cotton production in subtropical and tropical regions, with long-term economic and environmental benefits.

  7. Comparison of cotton square and boll damage and resulting lint and seed loss caused by verde plant bug, Creontiades signatus

    Science.gov (United States)

    Retention of bolls and squares (referred to as fruit retention), boll damage, and resulting cotton lint and seed weight loss were assessed when two (2010) and three (2011) age classes of sympodial fruiting branches with different ages of squares and bolls where exposed to verde plant bug, Creontiade...

  8. Ethylene-dependent effects on generative organ abscission of Lupinus luteus

    Directory of Open Access Journals (Sweden)

    Kamil Frankowski

    2017-03-01

    Full Text Available The abscission of certain organs from the plant is part of the fulfilment of its developmental programs. The separation process occurs in a specialized abscission zone usually formed at the base of detached organ. The changing level of phytohormones, particularly ethylene, is the element responsible for coordinating anatomical and physiological transformation that accompanies organ abscission. The application of ethylene (ET on Lupinus luteus stimulates flower abortion. However, the treatment with 1-aminocyclopropane-1-carboxylic acid (ACC – direct ET precursor – does not cause such a strong physiological response. In turn, when applied on the pedicels both ET biosynthesis (2-aminoethoxyvinylglycine; AVG and action (norbornadiene; NBD inhibitors reversed the stimulatory effect of ET on generative organ separation. In order to determine ET role in the flower abscission process in L. luteus, we identified the sequences coding for synthase (LlACS and oxidase (LlACO of ACC and measured their expression levels. Abscission zone activation is accompanied by a considerable increase both in LlACS and LlACO cDNAs and also ACC content, which is specifically localized in the dividing cells at the base of the flower being detached. Obtained results suggest that ET is a strong stimulator of flower abortion in L. luteus.

  9. The boll weevil plague and its effect on the southern agricultural sector, 1889–1929

    DEFF Research Database (Denmark)

    Ager, Philipp; Brueckner, Markus; Herz, Benedikt

    2017-01-01

    In the early 1890s, cotton fields in the American South were ravaged by the boll weevil. Using a model that controls for differences in the intensity of cotton production at the county level, we show how the boll weevil significantly changed southern agricultural labor arrangements and labor market...

  10. Continued pheromone release by boll weevils (Coleoptera: curculionidae) following host removal

    Science.gov (United States)

    Pheromone traps are a key component of management and eradication programs directed against the boll weevil, Anthonomus grandis (Boheman), but trap data remain difficult to interpret because of the day-to-day variability in captures. Our prior observations suggested a substantial proportion of boll...

  11. Attraction of dispersing boll weevils from surrounding habitats relative to simulated pheromone diffusion from traps

    Science.gov (United States)

    The ability to detect populations of boll weevils, Anthonomus grandis (Boheman), with pheromone traps has contributed significantly in progress toward eradication of the boll weevil. However, new information is needed to aid in the interpretation of trap captures, such as identification of habitats...

  12. Association of Verde plant bug, Creontiades signatus (Hemiptera: Miridae), with cotton boll rot

    Science.gov (United States)

    Cotton along the Gulf Coast of south Texas has experienced loss from cotton boll rot especially during the last 10 to 15 years, and stink bugs and plant bugs (Hemiptera: Pentatomidae and Miridae) that feed on cotton bolls have been suspected in introducing the disease. A replicated grower field surv...

  13. The Role of Leaves in Photocontrol of Flower Bud Abscission in Hibiscus rosa-sinensis L. 'Nairobi'

    NARCIS (Netherlands)

    Meeteren, van U.; Gelder, van A.

    2000-01-01

    When compared with exposure to darkness, exposing Hibiscus rosa-sinensis L. 'Nairobi' plants to red light (635 to 685 nm, 2.9 μmol?m-2?s-1) delayed flower bud abscission, while exposure to far-red light (705 to 755 nm, μmol?m-2?s-1) accelerated this process. Flower bud abscission in response to

  14. Separation of abscission zone cells in detached Azolla roots depends on apoplastic pH.

    Science.gov (United States)

    Fukuda, Kazuma; Yamada, Yoshiya; Miyamoto, Kensuke; Ueda, Junichi; Uheda, Eiji

    2013-01-01

    In studies on the mechanism of cell separation during abscission, little attention has been paid to the apoplastic environment. We found that the apoplastic pH surrounding abscission zone cells in detached roots of the water fern Azolla plays a major role in cell separation. Abscission zone cells of detached Azolla roots were separated rapidly in a buffer at neutral pH and slowly in a buffer at pH below 4.0. However, cell separation rarely occurred at pH 5.0-5.5. Light and electron microscopy revealed that cell separation was caused by a degradation of the middle lamella between abscission zone cells at both pH values, neutral and below 4.0. Low temperature and papain treatment inhibited cell separation. Enzyme(s) in the cell wall of the abscission zone cells might be involved in the degradation of the pectin of the middle lamella and the resultant, pH-dependent cell separation. By contrast, in Phaseolus leaf petioles, unlike Azolla roots, cell separation was slow and increased only at acidic pH. The rapid cell separation, as observed in Azolla roots at neutral pH, did not occur. Indirect immunofluorescence microscopy, using anti-pectin monoclonal antibodies, revealed that the cell wall pectins of the abscission zone cells of Azolla roots and Phaseolus leaf petioles looked similar and changed similarly during cell separation. Thus, the pH-related differences in cell separation mechanisms of Azolla and Phaseolus might not be due to differences in cell wall pectin, but to differences in cell wall-located enzymatic activities responsible for the degradation of pectic substances. A possible enzyme system is discussed. Copyright © 2012 Elsevier GmbH. All rights reserved.

  15. A developmental stage-specific switch from DAZL to BOLL occurs during fetal oogenesis in humans, but not mice.

    Directory of Open Access Journals (Sweden)

    Jing He

    Full Text Available The Deleted in Azoospermia gene family encodes three germ cell-specific RNA-binding proteins (DAZ, DAZL and BOLL that are essential for gametogenesis in diverse species. Targeted disruption of Boll in mice causes male-specific spermiogenic defects, but females are apparently fertile. Overexpression of human BOLL promotes the derivation of germ cell-like cells from genetically female (XX, but not male (XY human ES cells however, suggesting a functional role for BOLL in regulating female gametogenesis in humans. Whether BOLL is expressed during oogenesis in mammals also remains unclear. We have therefore investigated the expression of BOLL during fetal oogenesis in humans and mice. We demonstrate that BOLL protein is expressed in the germ cells of the human fetal ovary, at a later developmental stage than, and almost mutually-exclusive to, the expression of DAZL. Strikingly, BOLL is downregulated, and DAZL re-expressed, as primordial follicles form, revealing BOLL expression to be restricted to a narrow window during fetal oogenesis. By quantifying the extent of co-expression of DAZL and BOLL with markers of meiosis, we show that this window likely corresponds to the later stages of meiotic prophase I. Finally, we demonstrate that Boll is also transiently expressed during oogenesis in the fetal mouse ovary, but is simultaneously co-expressed within the same germ cells as Dazl. These data reveal significant similarities and differences between the expression of BOLL homologues during oogenesis in humans and mice, and raise questions as to the validity of the Boll(-/- mouse as a model for understanding BOLL function during human oogenesis.

  16. Stable isotope tracer marking of individual boll weevils

    International Nuclear Information System (INIS)

    James, W.D.; Showler, A.T.; Armstrong, J.S.; Westbrook, J.K.

    2006-01-01

    Stable isotope markers have been used to study animal nutrition for several decades and more recently to study the foraging and cultural habits of imported fire ants. In this work, we have extended that effort to evaluate the potential for marking boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), with the rare earth element samarium to aid in studies of insect invasion and pest eradication protocols. Neutron activation analysis (NAA) was performed on the marked boll weevils as well as plant material from the cotton squares on which the insects were fed. Samarium levels in non-dosed insects average about 20 ng/g or about 100 pg total element per insect. Our computed average determination limit was 36 pg samarium/weevil. The determination limit for cotton plant squares and leaves averaged 3.5 ng/g and 8.2 ng/g, respectively. These initial results indicate the NAA method is capable of identifying individual marked insects which have assimilated 1 ng of samarium, a ten-fold increase in content over average blank values. (author)

  17. Boll weevil: experimental sterilization of large numbers by fractionated irradiation

    International Nuclear Information System (INIS)

    Haynes, J.W.; Wright, J.E.; Davich, T.B.; Roberson, J.; Griffin, J.G.; Darden, E.

    1978-01-01

    Boll weevils, Anthonomus grandis grandis Boheman, 9 days after egg implantation in the larval diet were transported from the Boll Weevil Research Laboratory, Mississippi State, MS, to the Comparative Animal Research Laboratory, Oak Ridge, TN, and irradiated with 6.9 krad (test 1) or 7.2 krad (test 2) of 60 Co gamma rays delivered in 25 equal doses over 100 h. In test 1, from 600 individual pairs of T (treated) males x N (normal) females, only 114 eggs hatched from a sample of 950 eggs, and 47 adults emerged from a sample of 1042 eggs. Also, from 600 pairs of T females x N males, 6 eggs hatched of a sample of 6 eggs and 12 adults emerged from a sample of 20 eggs. In test 2, from 700 individual pairs of T males x N females, 54 eggs hatched from a sample of 1510, and 10 adults emerged from a sample of 1703 eggs. Also, in T females x N males matings, 1 egg hatched of a sample of 3, and no adults emerged from a sample of 4. Transportation and handling in the 2nd test reduced adult emergence an avg of 49%. Thus the 2 replicates in test 2 resulted in 3.4 x 10 5 and 4.3 x 10 5 irradiated weevils emerging/day for 7 days. Bacterial contamination of weevils was low

  18. Timing is everything: early degradation of abscission layer is associated with increased seed shattering in U.S. weedy rice

    Directory of Open Access Journals (Sweden)

    Hepler Peter K

    2011-01-01

    Full Text Available Abstract Background Seed shattering, or shedding, is an important fitness trait for wild and weedy grasses. U.S. weedy rice (Oryza sativa is a highly shattering weed, thought to have evolved from non-shattering cultivated ancestors. All U.S. weedy rice individuals examined to date contain a mutation in the sh4 locus associated with loss of shattering during rice domestication. Weedy individuals also share the shattering trait with wild rice, but not the ancestral shattering mutation at sh4; thus, how weedy rice reacquired the shattering phenotype is unknown. To establish the morphological basis of the parallel evolution of seed shattering in weedy rice and wild, we examined the abscission layer at the flower-pedicel junction in weedy individuals in comparison with wild and cultivated relatives. Results Consistent with previous work, shattering wild rice individuals possess clear, defined abscission layers at flowering, whereas non-shattering cultivated rice individuals do not. Shattering weedy rice from two separately evolved populations in the U.S. (SH and BHA show patterns of abscission layer formation and degradation distinct from wild rice. Prior to flowering, the abscission layer has formed in all weedy individuals and by flowering it is already degrading. In contrast, wild O. rufipogon abscission layers have been shown not to degrade until after flowering has occurred. Conclusions Seed shattering in weedy rice involves the formation and degradation of an abscission layer in the flower-pedicel junction, as in wild Oryza, but is a developmentally different process from shattering in wild rice. Weedy rice abscission layers appear to break down earlier than wild abscission layers. The timing of weedy abscission layer degradation suggests that unidentified regulatory genes may play a critical role in the reacquisition of shattering in weedy rice, and sheds light on the morphological basis of parallel evolution for shattering in weedy and wild

  19. Petal abscission in rose flowers: effects of water potential, light intensity and light quality

    NARCIS (Netherlands)

    Doorn, van W.G.; Vojinovic, A.

    1996-01-01

    Petal abscission was studied in roses (Rosa hybrida L.), cvs. Korflapei (trade name Frisco), Sweet Promise (Sonia) and Cara Mia (trade name as officially registered cultivar name). Unlike flowers on plants in greenhouses, cut flowers placed in water in the greenhouse produced visible symptoms of

  20. Semiochemicals from herbivory induced cotton plants enhance the foraging behavior of the cotton boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Magalhães, D M; Borges, M; Laumann, R A; Sujii, E R; Mayon, P; Caulfield, J C; Midega, C A O; Khan, Z R; Pickett, J A; Birkett, M A; Blassioli-Moraes, M C

    2012-12-01

    The boll weevil, Anthonomus grandis, has been monitored through deployment of traps baited with aggregation pheromone components. However, field studies have shown that the number of insects caught in these traps is significantly reduced during cotton squaring, suggesting that volatiles produced by plants at this phenological stage may be involved in attraction. Here, we evaluated the chemical profile of volatile organic compounds (VOCs) emitted by undamaged or damaged cotton plants at different phenological stages, under different infestation conditions, and determined the attractiveness of these VOCs to adults of A. grandis. In addition, we investigated whether or not VOCs released by cotton plants enhanced the attractiveness of the aggregation pheromone emitted by male boll weevils. Behavioral responses of A. grandis to VOCs from conspecific-damaged, heterospecific-damaged (Spodoptera frugiperda and Euschistus heros) and undamaged cotton plants, at different phenological stages, were assessed in Y-tube olfactometers. The results showed that volatiles emitted from reproductive cotton plants damaged by conspecifics were attractive to adults boll weevils, whereas volatiles induced by heterospecific herbivores were not as attractive. Additionally, addition of boll weevil-induced volatiles from reproductive cotton plants to aggregation pheromone gave increased attraction, relative to the pheromone alone. The VOC profiles of undamaged and mechanically damaged cotton plants, in both phenological stages, were not different. Chemical analysis showed that cotton plants produced qualitatively similar volatile profiles regardless of damage type, but the quantities produced differed according to the plant's phenological stage and the herbivore species. Notably, vegetative cotton plants released higher amounts of VOCs compared to reproductive plants. At both stages, the highest rate of VOC release was observed in A. grandis-damaged plants. Results show that A. grandis uses

  1. Effect of harvesting with a trunk shaker and an abscission chemical on fruit detachment and defoliation of citrus grown under Mediterranean conditions

    Directory of Open Access Journals (Sweden)

    Rosana Moreno

    2015-03-01

    Full Text Available Spain ranks as the world’s leading exporter of citrus for fresh consumption. Manual harvest accounts for 50% of the total production costs. Mechanical harvest would increase labor productivity and benefits of growers. Efficiency of these machines depends on the varieties and operating conditions. Use of abscission chemicals has been promoted to increase the detachment rate of fruit without affecting its quality. This work is aimed at studying whether the mechanical harvest and/or the application of an abscission agent affect the quality and quantity of harvested fruit and tree defoliation under the conditions of citrus cultivation in Spain. Trials were made in a completely randomized experimental design. From 2008 to 2011, different orchards of mandarin and orange trees were sprayed with different doses of ethephon as abscission agent and harvested with a trunk shaker. Harvest related variables (detachment percentage, defoliation and fruit without calyx were measured. The percentage of fruit detached by the trunk shaker ranged between 70 and 85% and it did not depend on the orchard. The shaker produced minimal damage to the bark when gripped incorrectly. Increased doses of ethephon increased fruit detachment except in ‘Clemenules’ orchard, but also increased the fruit without calyx in 1-9%. Moreover, ethephon promoted significant defoliation. Neither gummosis nor death of branches was observed. This work demonstrates that mechanical harvesting with trunk shakers may be a feasible solution for citrus cultivated in Spain for fresh market. Use of ethephon could only be recommended for citrus destined to industry and only for certain varieties.

  2. Effect of harvesting with a trunk shaker and an abscission chemical on fruit detachment and defoliation of citrus grown under Mediterranean conditions

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, R.; Torregrosa, A.; Moltó, E.; Chueca, P.

    2015-07-01

    Spain ranks as the world’s leading exporter of citrus for fresh consumption. Manual harvest accounts for 50% of the total production costs. Mechanical harvest would increase labor productivity and benefits of growers. Efficiency of these machines depends on the varieties and operating conditions. Use of abscission chemicals has been promoted to increase the detachment rate of fruit without affecting its quality. This work is aimed at studying whether the mechanical harvest and/or the application of an abscission agent affect the quality and quantity of harvested fruit and tree defoliation under the conditions of citrus cultivation in Spain. Trials were made in a completely randomized experimental design. From 2008 to 2011, different orchards of mandarin and orange trees were sprayed with different doses of ethephon as abscission agent and harvested with a trunk shaker. Harvest related variables (detachment percentage, defoliation and fruit without calyx) were measured. The percentage of fruit detached by the trunk shaker ranged between 70 and 85% and it did not depend on the orchard. The shaker produced minimal damage to the bark when gripped incorrectly. Increased doses of ethephon increased fruit detachment except in ‘Clemenules’ orchard, but also increased the fruit without calyx in 1-9%. Moreover, ethephon promoted significant defoliation. Neither gummosis nor death of branches was observed. This work demonstrates that mechanical harvesting with trunk shakers may be a feasible solution for citrus cultivated in Spain for fresh market. Use of ethephon could only be recommended for citrus destined to industry and only for certain varieties. (Author)

  3. Selective breeding for increased pheromone production in the boll weevil (Coleoptera: Curculionidae)

    International Nuclear Information System (INIS)

    McCoy, J.R.; Wright, J.E.

    1990-01-01

    The male boll weevil, Anthonomus grandis grandis Boheman, uses an aggregating pheromone to attract females, after which mating often occurs. Sterile boll weevil release programs depend upon this phenomenon to produce sterile matings with feral females. In an effort to increase the effectiveness of the individual sterile male and thereby reduce the number of sterile males required per hectare, a selective-breeding system was used to increase the total pheromone produced by individual male boll weevils. This breeding program increased the total pheromone production by individual male boll weevils to 4.5 times that of the parent population. After irradiation-induced sterilization, there remained 2.2 times more pheromone produced by the selected strain. Therefore, these sterile weevils should be about 2.2 times more attractive to feral females than the parent weevils now in use, and they have the potential to reduce the number of sterile males required in a sterile release program

  4. Primary and secondary abscission in Pisum sativum and Euphorbia pulcherrima –how do they compare and how do they differ?

    Directory of Open Access Journals (Sweden)

    Anne Kathrine (Trine eHvoslef-Eide

    2016-01-01

    Full Text Available ABSTRACTAbscission is a highly regulated and coordinated developmental process in plants. It is important to understand the processes leading up to the event, in order to better control abscission in crop plants. This has the potential to reduce yield losses in the field and increase the ornamental value of flowers and potted plants. A reliable method of abscission induction in poinsettia (Euphorbia pulcherrima flowers has been established to study the process in a comprehensive manner. By correctly decapitating buds of the third order, abscission can be induced in one week. AFLP differential display (DD was used to search for genes regulating abscission. Through validation using qRT-PCR, more information of the genes involved during induced secondary abscission have been obtained. A study using two mutants of pea (Pisum sativum in the def (Developmental funiculus gene have been performed and compared these with wild type peas (tall and dwarf in both cases. The def mutant results in a deformed, abscission-less zone instead of normal primary abscission at the funiculus. RNA in situ hybridization studies using gene sequences from the poinsettia differential display, resulted in six genes differentially expressed for abscission specific genes in both poinsettia and pea. Two of these genes are associated with gene up- or down-regulation during the first two days after decapitation in poinsettia. Present and previous results in poinsettia (biochemically and gene expressions, enables a more detailed division of the secondary abscission phases in poinsettia than what has previously been described from primary abscission in Arabidopsis.This study compares the inducible secondary abscission in poinsettia and the non-abscising mutants/wild types in pea demonstrating primary abscission zones. The results may have wide implications on the understanding of abscission, since pea and poinsettia have been separated for 94-98 million years in evolution, hence

  5. Reproductive dormancy in boll-weevil from populations of the midwest of Brazil.

    Science.gov (United States)

    Paula, D P; Claudino, D; Timbó, R V; Miranda, J E; Bemquerer, M P; Ribeiro, A C J; Sujii, E R; Fontes, E M G; Pires, C S S

    2013-02-01

    The boll weevil (Anthonomus grandis Boheman) (Coleoptera: Curculionidae) is an introduced pest in Brazil, which in 30 yr has successfully expanded to various eco-regions and became the most important pest of cotton (Gossypium hirsutum, Malvaceae). Given the limited knowledge about the adaptive mechanisms that allowed successful establishment of the pest population in a tropical region, in this work we studied the potential of the Midwest population of boll weevils to enter a reproductive dormancy and identified the importance of the feeding source for induction of dormancy. We investigated morphological and physiological characters as indicators of the dormancy. We also investigated the occurrence of reproductive dormancy in boll weevils populations from cotton farms of the Midwestern region of Brazil during the cotton and noncotton seasons of 2009 and 2010. The studies revealed that boll weevils entered facultative reproductive dormancy; however, unlike what has been observed for boll weevils from temperate and subtropical regions, the hypertrophy of fat body and hexamerin levels did not straightly correlated to reproductive dormancy. The food source and field conditions during early adult development were decisive factor for the induction of reproductive dormancy. The incidence of reproductive dormancy increased progressively as the phenology of cotton plant advanced, reaching approximately 90% at the end of the crop season. During the noncotton season, the boll weevil was predominantly found in reproductive dormancy, especially females; however, there is evidence of use of multiple adaptive strategies to colonize the next harvest.

  6. Survival and preference of cotton boll weevil adults for alternative food sources

    Directory of Open Access Journals (Sweden)

    M. Pimenta

    Full Text Available Abstract Plants that have potential as alternative food source (floral nectar, pollen and plant tissues to the boll weevil during the intercropping season were evaluated considering the prevalent conditions of Cerrado in the Central Brazil. Initially, we tested the nutritional adequacy for the survival of the insect of flower resource (pollen and nectar provided by eight plant species (fennel, mexican sunflower, castor bean, okra, hibiscus, sorghum, pigeonpea and sunn hemp. Subsequently, we tested if the resources provided by the selected plants continued to be exploited by the boll weevil in the presence of cotton plant, its main food source average longevity of boll weevil adults was significantly longer when they were fed on hibiscus’ flowers (166.6 ± 74.4 and okra flowers (34.7 ± 28.9 than when they fed on flowers of other six species. Subsequently, the preference of the boll weevil in the use of resources was compared between okra or hibiscus and cotton plants, in dual choice experiments. Boll weevils preferred plants of the three species in the reproductive stages than those in vegetative stages. Although the cotton plant in the reproductive stage was the most preferred plant of all, boll weevils preferred flowering okra and hibiscus than cotton at the vegetative stage.

  7. Components of competitiveness in sterile male boll weevils (Coleoptera: Curculionidae)

    International Nuclear Information System (INIS)

    Villavaso, E.J.; McGovern, W.L.; Wagner, T.L.; Willers, J.L.

    1998-01-01

    This study examines the relative importance of age at the time of irradiation on attractiveness, mating ability, sperm transfer, prior mating, and longevity as factors of competitiveness in sterile male boll weevil, Anthonomus grandis grandis Boheman. The amount of sperm transferred by irradiated males appeared to be the most important factor in competitiveness. More sperm was transferred by virgin males irradiated on day 5 than by virgin males irradiated on day 2, and males irradiated on day 5 had greater impact on egg hatch than those irradiated on day 2. The amount of sperm in spermathecae of females mated to virgin mates irradiated on day 5 was indistinguishable from that in females mated to virgin control males. Mating ability of males of all treatments was similar. Comparable numbers of boll weevils were captured in traps baited with males irradiated at 2 or 5 d during the first 4-5 d after irradiation, but thereafter, generally more weevils were captured in traps baited with males irradiated at 2 d or with control males. Attractiveness of males irradiated at 2 d was generally comparable to that of control males. More than 91% of irradiated males individually caged on cotton, Gossypium hirsutum L., plants lived for 10 d in the field, and 40% lived for 14 d; all individually caged control males lived 14 d. When released into cotton fields, however, the numbers of both irradiated and control males declined sharply over 14 d. Thus, the potential for an effective 2-wk life span in the field suggested by the caged study did not appear to apply to laboratory-reared weevils released into cotton fields

  8. Fatty acid and sterol contents during methyl jasmonate-induced leaf abscission in Kalanchoe blossfeldiana

    Directory of Open Access Journals (Sweden)

    Marian Saniewski

    2013-12-01

    Full Text Available It was found previously that methyl jasmonate (JA-Me induced leaf abscission in Kalanchoe blossfeldiana. In present studies it was showed that JA-Me did not affect or only slightly affected the content of free and bound fatty acids in petioles and blades. ß-Sitosterol, campesterol and ß-amyrin were identified in petioles and blades of K. blossfeldiana; JA-Me decreased the content of campesterol in petioles and increased the content of ß-sitosterol in blades. In blades of plants treated with JA-Me disappearance of olean-12-one was indicated but appearance of 2H-cyclopropa[a]-naphthalen-2-one,l, la, 4, 5, 6, 7, 7a, 7b-octahydro-l, 1, 7, 7a-tetramethyl (aristolone was documented. The significance of these findings in leaf abscission induced by methyl jasmonate in K. blossfeldiana is discussed.

  9. 1-MCP pretreatment prevents bud and flower abscission in Dendrobium orchids

    NARCIS (Netherlands)

    Uthaichay, N.; Ketsa, S.; Doorn, van W.G.

    2007-01-01

    Dendrobium orchid inflorescences were treated for 4 h at 25 °C with or without 100¿500 nl/l 1-MCP and were then placed in water at 25 °C to follow abscission. In controls, depending on the experiment, 20¿80% of the floral buds and 0¿20% of the open flowers abscised within 1 week. The 1-MCP

  10. Identifying the candidate genes involved in the calyx abscission process of 'Kuerlexiangli' (Pyrus sinkiangensis Yu) by digital transcript abundance measurements.

    Science.gov (United States)

    Qi, Xiaoxiao; Wu, Jun; Wang, Lifen; Li, Leiting; Cao, Yufen; Tian, Luming; Dong, Xingguang; Zhang, Shaoling

    2013-10-23

    'Kuerlexiangli' (Pyrus sinkiangensis Yu), a native pear of Xinjiang, China, is an important agricultural fruit and primary export to the international market. However, fruit with persistent calyxes affect fruit shape and quality. Although several studies have looked into the physiological aspects of the calyx abscission process, the underlying molecular mechanisms remain unknown. In order to better understand the molecular basis of the process of calyx abscission, materials at three critical stages of regulation, with 6000 × Flusilazole plus 300 × PBO treatment (calyx abscising treatment) and 50 mg.L-1GA3 treatment (calyx persisting treatment), were collected and cDNA fragments were sequenced using digital transcript abundance measurements to identify candidate genes. Digital transcript abundance measurements was performed using high-throughput Illumina GAII sequencing on seven samples that were collected at three important stages of the calyx abscission process with chemical agent treatments promoting calyx abscission and persistence. Altogether more than 251,123,845 high quality reads were obtained with approximately 8.0 M raw data for each library. The values of 69.85%-71.90% of clean data in the digital transcript abundance measurements could be mapped to the pear genome database. There were 12,054 differentially expressed genes having Gene Ontology (GO) terms and associating with 251 Kyoto Encyclopedia of Genes and Genomes (KEGG) defined pathways. The differentially expressed genes correlated with calyx abscission were mainly involved in photosynthesis, plant hormone signal transduction, cell wall modification, transcriptional regulation, and carbohydrate metabolism. Furthermore, candidate calyx abscission-specific genes, e.g. Inflorescence deficient in abscission gene, were identified. Quantitative real-time PCR was used to confirm the digital transcript abundance measurements results. We identified candidate genes that showed highly dynamic changes in

  11. Transcriptomic signatures in seeds of apple (Malus domestica L. Borkh) during fruitlet abscission.

    Science.gov (United States)

    Ferrero, Sergio; Carretero-Paulet, Lorenzo; Mendes, Marta Adelina; Botton, Alessandro; Eccher, Giulia; Masiero, Simona; Colombo, Lucia

    2015-01-01

    Abscission is the regulated process of detachment of an organ from a plant. In apple the abscission of fruits occurs during their early development to control the fruit load depending on the nutritional state of the plant. In order to control production and obtain fruits with optimal market qualities, the horticultural procedure of thinning is performed to further reduce the number of fruitlets. In this study we have conducted a transcriptomic profiling of seeds from two different types of fruitlets, according to size and position in the fruit cluster. Transcriptomic profiles of central and lateral fruit seeds were obtained by RNAseq. Comparative analysis was performed by the functional categorization of differentially expressed genes by means of Gene Ontology (GO) annotation of the apple genome. Our results revealed the overexpression of genes involved in responses to stress, hormone biosynthesis and also the response and/or transport of auxin and ethylene. A smaller set of genes, mainly related to ion transport and homeostasis, were found to be down-regulated. The transcriptome characterization described in this manuscript contributes to unravelling the molecular mechanisms and pathways involved in the physiological abscission of apple fruits and suggests a role for seeds in this process.

  12. Genome-Wide Identification of Histone Modifiers and Their Expression Patterns during Fruit Abscission in Litchi

    Directory of Open Access Journals (Sweden)

    Jianguo Li

    2017-04-01

    Full Text Available Modifications to histones, including acetylation and methylation processes, play crucial roles in the regulation of gene expression in plant development as well as in stress responses. However, limited information on the enzymes catalyzing histone acetylation and methylation in non-model plants is currently available. In this study, several histone modifier (HM types, including six histone acetyltransferases (HATs, 11 histone deacetylases (HDACs, 48 histone methyltransferases (HMTs, and 22 histone demethylases (HDMs, are identified in litchi (Litchi chinensis Sonn. cv. Feizixiao based on similarities in their sequences to homologs in Arabidopsis (A. thaliana, tomato (Solanum lycopersicum, and rice (Oryza sativa. Phylogenetic analyses reveal that HM enzymes can be grouped into four HAT, two HDAC, two HMT, and two HDM subfamilies, respectively, while further expression profile analyses demonstrate that 17 HMs were significantly altered during fruit abscission in two field treatments. Analyses reveal that these genes exhibit four distinct patterns of expression in response to fruit abscission, while an in vitro assay was used to confirm the HDAC activity of LcHDA2, LcHDA6, and LcSRT2. Our findings are the first in-depth analysis of HMs in the litchi genome, and imply that some are likely to play important roles in fruit abscission in this commercially important plant.

  13. Collection of pheromone from atmosphere surrounding boll weevils,Anthonomus grandis.

    Science.gov (United States)

    Chang, J F; Benedict, J H; Payne, T L; Camp, B J; Vinson, S B

    1989-02-01

    An effluvial method was developed to collect the pheromone, grandlure from actively calling male boll weevils,Anthonomus grandis Boheman. The adsorbant, Porapak Q (ethylvinylbenzene-divinylbenzene), was utilized to trap and concentrate the pheromone. Captured pheromone was desorbed from columns packed with Porapak Q by elution withn-pentane and quantified by capillary column gas-liquid chromatography. In recovery studies with known amounts of synthetic grandlure, we found that the amount of each pheromone component collected was a function of collection duration, elution volume, and initial concentration. This effluvial method was capable of recovering as much as 94.9% of a known quantity (80 μg) of grandlure. The chromatograms were free of extraneous peaks. In studies of insect-produced pheromone, the effluvial method was used to collect pheromone from the air space surrounding male boll weevils as they fed on flower buds from CAMD-E cotton. The quantity and quality of boll-weevil-produced pheromone was determined for days 6, 8, 10, 11, 12, 13, and 14 of boll weevil adulthood. The maximum quantity of natural pheromone was produced on day 13 (4.2 μg/weevil) with a pheromone component ratio of 2.41∶2.29∶0.95∶1 for components I, II, III, and IV, respectively. The effluvial method described in this report is an efficient method to collect and quantify boll weevil pheromone from the atmosphere surrounding actively calling insects. Other applications of this method are suggested.

  14. Morphology, diet, and temperature dependent host-free survival of the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae)

    Science.gov (United States)

    The boll weevil, Anthonomus grandis grandis Boheman, is an important pest of cotton (Gossypium spp.) in South America, Mexico, and southernmost Texas in the United States. A key factor in the persistence of the boll weevil is its ability to survive the non-cotton season. Mechanisms facilitating this...

  15. Failure of pheromone traps in detecting incipient populations of boll weevils (Coleoptera: Curculionidae): Investigation of two potential contributing factors

    Science.gov (United States)

    Progress towards complete eradication of the boll weevil has been delayed in some areas of Texas due to the inconsistent performance of pheromone traps in detecting incipient weevil populations. In 2008 substantial infestations of boll weevils, Anthonomus grandis Boheman, were detected in several c...

  16. Effects of Temperature and Adult Diet on Development of Hypertrophied Fat Body in Prediapausing Boll Weevil (Coleoptera Curculionidae)

    Science.gov (United States)

    Terence L. Wagner; Eric J. Villavaso

    1999-01-01

    This study examines the effects of temperature and adult diet on the development of hypertrophied fat bodies in prediapausing adult boll weevils, Anthonomus grandis grandis Boheman. Simulation models derived from this work are used to estimate the minimal ages at which male and female boll weevils exhibit diapause morphology, based on conditions...

  17. Efficacy of fipronil aerially applied in oil adjuvants and drift retardants against boll weevils, Anthonomus Grandis Boheman (Coleoptera:Curculionidae)

    Science.gov (United States)

    Joseph E. Mulrooney

    2002-01-01

    Results of aerial application tests in the field and insecticide transfer tests in the laboratory showed that cottonseed oil was the most effective oil adjuvant to use with fipronil for controlling boll weevils under field conditions and for transferring fipronil from cotton leaf surfaces to boll weevils. The mineral oil and mineral oil + drift retardant more...

  18. Ecology and phenology of the boll weevil (Coleoptera: Curculionidae) on an unusual wild host, Hibiscus pernambucensis, in southeastern Mexico.

    Science.gov (United States)

    Arzaluz, I O; Jones, R W

    2001-12-01

    The phenology and ecology of Hibiscus pernambucensis Arruda and its interaction and importance in maintaining populations of the boll weevil, Anthonomus grandis Boheman, were studied over a period of 3 yr in the Soconusco Region of the state of Chiapas, Mexico. H. pernambucensis is a small tree of Neotropical distribution, restricted to lowland areas, and generally associated with halophytic vegetation. This species is found exclusively along the shores of brackish estuaries, in or near mangrove swamps in southeastern Mexico. In this region, H. pernambucensis has a highly seasonal flowering pattern in which the greatest bud production occurs shortly after the start of the rainy season in May and the highest fruit production occurs in July and August. Boll weevil larvae were found in buds of H. pernambucensis during all months but February and densities of buds and weevils were highest from May through September. The percentage of buds infested with boll weevil larvae rarely exceeded 30%. Because plant densities and reproductive output of H. pernambucensis is relatively low and, consequently, the number of oviposition and larval development sites for boll weevils is limited, the importance of this plant as a source of boll weevils with potential of attacking commercial cotton is minimal in comparison with the quantity produced in cultivated cotton. However, the plant could be important as a reservoir of boll weevils in areas of boll weevil quarantine and eradication programs. The factors and circumstances that may have led to this apparent recent host shift of the boll weevil in this region are discussed.

  19. Molecular diagnostic for boll weevil (Coleoptera: Curculionidae) based on amplification of three species-specific microsatellites.

    Science.gov (United States)

    Kim, Kyung Seok; Szendrei, Zsofia; Rodriguez-Saona, Cesar; Mulder, Phillip G; Sappington, Thomas W

    2009-04-01

    The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton, Gossypium hirsutum L., in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally the traps collect nontarget weevils that can be misidentified by scouts. For example, the congeneric pepper weevil, Anthonomus eugenii Cano, and other superficially similar weevils are attracted to components of the boll weevil lure or trap color. Although morphologically distinguishable by trained personnel, the potential for misidentification is compounded when captured weevils are dismembered or partially consumed by ants or ground beetles that sometimes feed on them in the traps. Because misidentification can have expensive consequences, a molecular diagnostic tool would be of great value to eradication managers. We demonstrate that a cocktail of three primer pairs in a single polymerase chain reaction (PCR) amplify species-specific microsatellites that unambiguously distinguish the boll weevil from three other weevil species tested, including pepper weevil; cranberry weevil, Anthonomus eugenii musculus Say; and pecan weevil, Curculio caryae Horn. However, it does not distinguish the boll weevil from the subspecific "thurberia" weevil. A universal internal transcribed spacer primer pair included in the cocktail cross-amplifies DNA from all species, serving as a positive control. Furthermore, the diagnostic primers amplified the target microsatellites from various boll weevil adult body parts, indicating that the PCR technology using the primer cocktail is sensitive enough to positively identify a boll weevil even when the body is partly degraded.

  20. Aggregation and Association of NDVI, Boll Injury, and Stink Bugs in North Carolina Cotton.

    Science.gov (United States)

    Reisig, Dominic D; Reay-Jones, F P F; Meijer, A D

    2015-01-01

    Sampling of herbivorous stink bugs in southeastern U.S. cotton remains problematic. Remote sensing was explored to improve sampling of these pests and associated boll injury. Two adjacent 14.5-ha cotton fields were grid sampled in 2011 and 2012 by collecting stink bug adults and bolls every week during the third, fourth, and fifth weeks of bloom. Satellite remote sensing data were collected during the third week of bloom during both years, and normalized difference vegetation index (NDVI) values were calculated. Stink bugs were spatially aggregated on the third week of bloom in 2011. Boll injury from stink bugs was spatially aggregated during the fourth week of bloom in 2012. The NDVI values were aggregated during both years. There was a positive association and correlation between stink bug numbers and NDVI values, as well as injured bolls and NDVI values, during the third week of bloom in 2011. During the third week of bloom in 2012, NDVI values were negatively correlated with stink bug numbers. During the fourth week of bloom in 2011, stink bug numbers and boll injury were both positively associated and correlated with NDVI values. During the fourth week of bloom in 2012, stink bugs were negatively correlated with NDVI values, and boll injury was negatively associated and correlated with NDVI values. This study suggests the potential of remote sensing as a tool to assist with sampling stink bugs in cotton, although more research is needed using NDVI and other plant measurements to predict stink bug injury. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.

  1. Effect of temperature on the reproduction of Bracon vulgaris Ashmead (Hymenoptera: Braconidae), a parasitoid of the cotton boll weevil.

    Science.gov (United States)

    Ramalho, Francisco S; Wanderley, Paulo A; Malaquias, José B; Fernandes, Francisco S; Nascimento, Antônio R B; Zanuncio, José C

    2011-09-01

    This research studied the effect of temperature on the reproduction of Bracon vulgaris Ashmead, an ectoparasitoid of cotton boll weevil ( Anthonomus grandis Boheman) at constant temperatures of 20, 25 and 30ºC, 70 ± 10% RH and a photophase of 14 h. Females of the parasitoid produced a greater number of eggs when exposed to 25ºC (124.65 eggs) in relation to those exposed to 20 (43.40 eggs) and 30ºC (49.60 eggs). The number of parasitized larvae per female of B. vulgaris at 25ºC (71.75) was greater than at 20ºC (31.40) and 30ºC (25.15). The daily intrinsic rates of increase (r m) were - 0.007 at 20ºC, 0.07 at 25ºC and 0.03 at 30ºC, revealing that the temperature of 25ºC produced increases of 1,100 and 133% in the value r m in relation to temperatures of 20 and 30ºC, respectively. In programs of biological control of the boll weevil using innoculative releases, adult females of B. vulgaris with approximately five (at 25 or 30ºC) or 20 day old (at 20ºC) should be used; when using innundative releases, adult females of B. vulgaris , with ages between 11 and 31; 9 and 29 or 3 and 14 days, respectively, at 20, 25 or 30ºC should be used.

  2. Evaluation of extended-life pheromone formulations used with and without dichlorvos for boll weevil (Coleoptera: Curculionidae) trapping.

    Science.gov (United States)

    Armstrong, J Scott; Greenberg, Shoil M

    2008-04-01

    Boll weevil traps baited with a ComboLure (25 of mg grandlure + 30 mg of eugenol + 90 of mg dichlorvos [DDVP]), an extended-release lure (25 mg of grandlure + 30 mg of eugenol + 60 of mg DDVP kill-strip), and extended-release lure with no DDVP were evaluated for boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), captures in South Texas cotton, Gossypium hirsutum L., fields during February-March 2005 and March-April 2006. The traps were serviced once a week for five consecutive weeks by using the same methodology as active boll weevil eradication programs. Mean captured boll weevils from extended-release lures with no DDVP were significantly higher in five of 10 trapping weeks compared with captures of the ComboLure and extended lure. Weekly mortality of boll weevils captured was similar for the ComboLure (72.6 +/- 4.7%) and extended lure + DDVP (73.5 +/- 4.0%), and both were significantly higher than the extended lure (32.8 +/- 5.0%) with no DDVP. The presence or absence of DDVP did not significantly affect the sex ratio of field-captured boll weevils. We found no functional reasoning for using DDVP in large scale trapping of boll weevils regardless of the formulation or presentation in the trap. We conducted two additional trapping evaluations after the 2005 and 2006 studies, but the numbers of boll weevils captured were too low for statistical comparisons, indicating that boll weevil eradication is reducing populations in the Rio Grande Valley of Texas.

  3. Boll weevil (Anthonomus grandis) population genomics as a tool for monitoring and management

    Science.gov (United States)

    Despite the success of eradication efforts across most of the cotton-producing regions of the U.S., the cotton boll weevil (Anthonomus grandis grandis Boheman) remains a major pest of cotton in much of the New World. The area along the Texas border with northern Mexico has been a particularly troub...

  4. Investigation of pheromone-based factors that may reduce capture of boll weevils in traps

    Science.gov (United States)

    Boll weevil (Anthonomus grandis Boheman) eradication programs rely almost exclusively on pheromone traps to detect weevils, assess populations, and indicate the need for insecticide treatment. However, instances have been reported recently in Medina Co., TX, where field infestations occur without p...

  5. Temperature influences on diapause induction and survival in the boll weevil (Coleoptera: Curculionidae)

    Science.gov (United States)

    The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), has been the most important pest of cotton (Gossypium spp.) wherever it occurs. Although eradication programs in the U.S. have reduced the range of this pest, the weevil remains an intractable problem in subtropical Tex...

  6. Quantification of dichlorvos released from kill strips used in boll weevil eradication programs

    Science.gov (United States)

    Two types of kill strips, Hercon Vaportape II and Plato Insecticide Strip, are used by boll weevil, Anthonomus grandis (Boheman), eradication programs in the U.S. Both types utilize dichlorvos as the killing agent and are marketed to last up to a month in traps. Consequently, programs typically re...

  7. Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis).

    Science.gov (United States)

    Oliveira, Gustavo R; Silva, Maria C M; Lucena, Wagner A; Nakasu, Erich Y T; Firmino, Alexandre A P; Beneventi, Magda A; Souza, Djair S L; Gomes, José E; de Souza, José D A; Rigden, Daniel J; Ramos, Hudson B; Soccol, Carlos R; Grossi-de-Sa, Maria F

    2011-09-09

    The cotton boll weevil (Anthonomus grandis) is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

  8. Effects of soybean Kunitz trypsin inhibitor on the cotton boll weevil (Anthonomus grandis).

    Science.gov (United States)

    Franco, Octávio L; Dias, Simoni C; Magalhães, Claudio P; Monteiro, Ana C S; Bloch, Carlos; Melo, Francislete R; Oliveira-Neto, Osmundo B; Monnerat, Rose G; Grossi-de-Sá, Maria Fátima

    2004-01-01

    The cotton boll weevil, Anthonomus grandis, is an economically important pest of cotton in tropical and subtropical areas of several countries in the Americas, causing severe losses due to their damage in cotton floral buds. Enzymatic assays using gut extracts from larval and adult boll weevil have demonstrated the presence of digestive serine proteinase-like activities. Furthermore, in vitro assays showed that soybean Kunitz trypsin inhibitor (SKTI) was able to inhibit these enzymes. Previously, in vivo effects of black-eyed pea trypsin chymotrypsin inhibitor (BTCI) have been demonstrated towards the boll weevil pest. Here, when neonate larvae were reared on an artificial diet containing SKTI at three different concentrations, a reduction of larval weight of up to 64% was observed for highest SKTI concentration 500 microM. The presence of SKTI caused an increase in mortality and severe deformities of larvae, pupae and adult insects. This work therefore represents the first observation of a Kunitz trypsin inhibitor active in vivo and in vitro against A. grandis. Bioassays suggested that SKTI could be used as a tool in engineering crop plants, which might exhibit increased resistance against cotton boll weevil.

  9. Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis

    Directory of Open Access Journals (Sweden)

    Gomes José E

    2011-09-01

    Full Text Available Abstract Background The cotton boll weevil (Anthonomus grandis is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Results Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. Conclusions The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

  10. Starvation-induced morphological responses of the boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae)

    Science.gov (United States)

    Status of the boll weevil, Anthonomus grandis grandis Boheman, as a pest of cotton (Gossypium spp.) in the United States has diminished because of progress by eradication programs. However, this pest remains of critical importance in South America, and intractable populations in extreme South Texas ...

  11. Work of the social effects of automation committee from bad boll to enschede

    NARCIS (Netherlands)

    Withers, R.M.J.; Rijnsdorp, J.E.

    1978-01-01

    The paper summarises the activities of the IFAC Committee on Social Effects of Automation during the period 1974–1977. A workshop was held about ‘Productivity and Man’ at Bad Boll (F.R.G.) in January 1974. A number of Newsletters were published. Factory visits were made to a Steel Rolling Mill, an

  12. Molecular Diagnostic for Boll Weevil (Coleoptera: Curculionidae) Based on Amplification of Three Species-specific Microsatellites

    Science.gov (United States)

    The boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally...

  13. Verde plant bug is associated with cottong boll rot in South Texas cotton

    Science.gov (United States)

    Verde plant bug was the dominant boll-feeding sucking bug species (>98% of insects collected using a beat bucket) from peak to late bloom in cotton fields near the coast along the Coastal Bend of South Texas, from Port Lavaca to the Lower Rio qrande Valley in 2010 and 2011. It was common in fields w...

  14. Diapause in the Boll Weevil (Coleopetra: Curculionidae) : Life-Stage Sensitivity to Enviromental Cues

    Science.gov (United States)

    Terence L. Wagner; Eric J. Villavaso; Jefferey L. Willers

    1999-01-01

    This study examines the diapause response in naturally occurring boll weevils under field and simulated field environments of north Mississippi. Squares containing early-stage weevils were collected in July, August, and September and subsamples from each group were installed into similar dynamic environments in the laboratory. In this manner, some weevils experienced...

  15. 紫丁香叶柄离区IAA的免疫组织化学定位%Immunohistochemical Localization of IAA in the Leaf Abscission Zone of Syringa oblata

    Institute of Scientific and Technical Information of China (English)

    王幼群; 韩静; 林金星

    2001-01-01

    Freezing sections and immunogold-silver staining were employed tothe study on the localization of IAA in petioles of Syringa oblata Lind. At different stages of leaf abscission, the distribution patterns of the silver particles varied in different tissues. In the earlier period of abscission, there were many silver particles in the proximal and distal tissues, but only a few in the abscission zone. The high density of silver particles was found in the phloem of the petiole. The number of silver particles in the abscission zone increase immediately after the protective layer was formed and began to decrease along with the development of the abscission zone. The density of the silver particles became very low when abscission was completed. The formation of protective layer may be the demarcation line of the Stage Ⅰ and Stage Ⅱ during the development of the abscission zone.

  16. Abscission zone development in Setaria viridis and its domesticated relative, Setaria italica.

    Science.gov (United States)

    Hodge, John G; Kellogg, Elizabeth A

    2016-06-01

    Development of an abscission zone (AZ) is needed for dispersal of seeds, and AZ loss was a critical early step in plant domestication. The AZ forms in different tissues in different species of plants, but whether the AZ is developmentally similar wherever it occurs is unknown. AZ development in Setaria viridis was studied as a representative of the previously uncharacterized subfamily Panicoideae. One accession of the wild species S. viridis and two of its domesticate, S. italica, were studied. Strength of the AZ was measured with a force gauge. Anatomy of the AZ was studied throughout development using bright field and confocal microscopy. The force required to remove a spikelet of S. viridis from the parent plant dropped steadily during development, whereas that required to remove spikelets of S. italica increased initially before stabilizing at a high level. Despite the clear difference in tensile strength of the AZ, anatomical differences between S. viridis and S. italica were subtle, and the position of the AZ was not easy to determine in cross sections of pedicel apices. Staining with DAPI showed that nuclei were present up to and presumably through abscission in S. viridis, and acridine orange staining showed much less lignification than in other cereals. The AZ in Setaria is developmentally and anatomically different from that characterized in rice, barley, and many eudicots. In particular, no set of small, densely cytoplasmic cells is obvious. This difference in anatomy could point to differential genetic control of the structure. © 2016 Botanical Society of America.

  17. Controlled free radical attack in the apoplast: a hypothesis for roles of O, N and S species in regulatory and polysaccharide cleavage events during rapid abscission by Azolla.

    Science.gov (United States)

    Cohen, Michael F; Gurung, Sushma; Fukuto, Jon M; Yamasaki, Hideo

    2014-03-01

    Shedding of organs by abscission is a key terminal step in plant development and stress responses. Cell wall (CW) loosening at the abscission zone can occur through a combination chain breakage of apoplastic polysaccharides and tension release of cellulose microfibrils. Two distinctly regulated abscission cleavage events are amenable to study in small water ferns of the genus Azolla; one is a rapid abscission induced by environmental stimuli such as heat or chemicals, and the other is an ethylene-induced process occurring more slowly through the action of hydrolytic enzymes. Although free radicals are suggested to be involved in the induction of rapid root abscission, its mechanism is not fully understood. The apoplast contains peroxidases, metal-binding proteins and phenolic compounds that potentially generate free radicals from H2O2 to cleave polysaccharides in the CW and middle lamella. Effects of various thiol-reactive agents implicate the action of apoplastic peroxidases having accessible cysteine thiols in rapid abscission. The Ca(2+) dependency of rapid abscission may reflect the stabilization Ca(2+) confers to peroxidase structure and binding to pectin. To spur further investigation, we present a hypothetical model for small signaling molecules H2O2 and NO and their derivatives in regulating, via modification of putative protein thiols, free radical attack of apoplastic polysaccharides. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  18. Captures of Boll Weevils (Coleoptera: Curculionidae) in Relation to Trap Orientation and Distance From Brush Lines.

    Science.gov (United States)

    Spurgeon, Dale W

    2016-04-01

    Eradication programs for the boll weevil (Anthonomus grandis grandis Boheman) rely on pheromone-baited traps to trigger insecticide treatments and monitor program progress. A key objective of monitoring in these programs is the timely detection of incipient weevil populations to limit or prevent re-infestation. Therefore, improvements in the effectiveness of trapping would enhance efforts to achieve and maintain eradication. Association of pheromone traps with woodlots and other prominent vegetation are reported to increase captures of weevils, but the spatial scale over which this effect occurs is unknown. The influences of trap distance (0, 10, and 20 m) and orientation (leeward or windward) to brush lines on boll weevil captures were examined during three noncropping seasons (October to February) in the Rio Grande Valley of Texas. Differences in numbers of captured weevils and in the probability of capture between traps at 10 or 20 m from brush, although often statistically significant, were generally small and variable. Variations in boll weevil population levels, wind directions, and wind speeds apparently contributed to this variability. In contrast, traps closely associated with brush (0 m) generally captured larger numbers of weevils, and offered a higher probability of weevil capture compared with traps away from brush. These increases in the probability of weevil capture were as high as 30%. Such increases in the ability of traps to detect low-level boll weevil populations indicate trap placement with respect to prominent vegetation is an important consideration in maximizing the effectiveness of trap-based monitoring for the boll weevil.

  19. Effects of photoperiod on boll weevil (Coleoptera: Curculionidae) development, survival, and reproduction.

    Science.gov (United States)

    Greenberg, S M; Sappington, T W; Adamczyk, J J; Liu, T-X; Setamou, M

    2008-12-01

    Effects of photoperiod on development, survival, feeding, and oviposition of boll weevils, Anthonomus grandis grandis Boheman, were assessed under five different photophases (24, 14, 12, 10, and 0 h) at a constant 27 degrees C temperature and 65% RH in the laboratory. Analyses of our results detected positive relationships between photoperiod and puncturing (mean numbers of oviposition and feeding punctures per day), and oviposition (oviposition punctures/oviposition+feeding punctures) activities, and the proportion of squares attacked by boll weevil females. When boll weevil females developed in light:darkness cycles, they produced a significantly higher percentage of eggs developing to adulthood than those developed in 24-h light or dark conditions. In long photoperiod (24:0 and 14:10 h), the number of female progeny was significantly higher and their development time was significantly shorter than those developed in short photoperiod (0:24 and 10:14 h). Lifetime oviposition was significantly highest at 12- and 14-h photophase, lowest at 0- and 10-h photophase, and intermediate at 24 h of light. Life table calculations indicated that boll weevil populations developed in a photoperiod of 14:10 and 12:12 (L:D) h will increase an average of two-fold each generation (Ro) compared with boll weevils developed in 24:0- and 10:14-h photoperiods and 15-fold compared with those at 0:24 h. Knowledge of the photoperiod-dependent population growth potential is critical for understanding population dynamics to better develop sampling protocols and timing insecticide applications.

  20. Stability of Spatial Distributions of Stink Bugs, Boll Injury, and NDVI in Cotton.

    Science.gov (United States)

    Reay-Jones, Francis P F; Greene, Jeremy K; Bauer, Philip J

    2016-10-01

    A 3-yr study was conducted to determine the degree of aggregation of stink bugs and boll injury in cotton, Gossypium hirsutum L., and their spatial association with a multispectral vegetation index (normalized difference vegetation index [NDVI]). Using the spatial analysis by distance indices analyses, stink bugs were less frequently aggregated (17% for adults and 4% for nymphs) than boll injury (36%). NDVI values were also significantly aggregated within fields in 19 of 48 analyses (40%), with the majority of significant indices occurring in July and August. Paired NDVI datasets from different sampling dates were frequently associated (86.5% for weekly intervals among datasets). Spatial distributions of both stink bugs and boll injury were less stable than for NDVI, with positive associations varying from 12.5 to 25% for adult stink bugs for weekly intervals, depending on species. Spatial distributions of boll injury from stink bug feeding were more stable than stink bugs, with 46% positive associations among paired datasets with weekly intervals. NDVI values were positively associated with boll injury from stink bug feeding in 11 out of 22 analyses, with no significant negative associations. This indicates that NDVI has potential as a component of site-specific management. Future work should continue to examine the value of remote sensing for insect management in cotton, with an aim to develop tools such as risk assessment maps that will help growers to reduce insecticide inputs. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Overexpression of a novel MADS-box gene SlFYFL delays senescence, fruit ripening and abscission in tomato

    Science.gov (United States)

    Xie, Qiaoli; Hu, Zongli; Zhu, Zhiguo; Dong, Tingting; Zhao, Zhiping; Cui, Baolu; Chen, Guoping

    2014-03-01

    MADS-domain proteins are important transcription factors involved in many biological processes of plants. In our study, a tomato MADS-box gene, SlFYFL, was isolated. SlFYFL is expressed in all tissues of tomato and significantly higher in mature leave, fruit of different stages, AZ (abscission zone) and sepal. Delayed leaf senescence and fruit ripening, increased storability and longer sepals were observed in 35S:FYFL tomato. The accumulation of carotenoid was reduced, and ethylene content, ethylene biosynthetic and responsive genes were down-regulated in 35S:FYFL fruits. Abscission zone (AZ) did not form normally and abscission zone development related genes were declined in AZs of 35S:FYFL plants. Yeast two-hybrid assay revealed that SlFYFL protein could interact with SlMADS-RIN, SlMADS1 and SlJOINTLESS, respectively. These results suggest that overexpression of SlFYFL regulate fruit ripening and development of AZ via interactions with the ripening and abscission zone-related MADS box proteins.

  2. Transgenic cotton expressing Cry10Aa toxin confers high resistance to the cotton boll weevil.

    Science.gov (United States)

    Ribeiro, Thuanne Pires; Arraes, Fabricio Barbosa Monteiro; Lourenço-Tessutti, Isabela Tristan; Silva, Marilia Santos; Lisei-de-Sá, Maria Eugênia; Lucena, Wagner Alexandre; Macedo, Leonardo Lima Pepino; Lima, Janaina Nascimento; Santos Amorim, Regina Maria; Artico, Sinara; Alves-Ferreira, Márcio; Mattar Silva, Maria Cristina; Grossi-de-Sa, Maria Fatima

    2017-08-01

    Genetically modified (GM) cotton plants that effectively control cotton boll weevil (CBW), which is the most destructive cotton insect pest in South America, are reported here for the first time. This work presents the successful development of a new GM cotton with high resistance to CBW conferred by Cry10Aa toxin, a protein encoded by entomopathogenic Bacillus thuringiensis (Bt) gene. The plant transformation vector harbouring cry10Aa gene driven by the cotton ubiquitination-related promoter uceA1.7 was introduced into a Brazilian cotton cultivar by biolistic transformation. Quantitative PCR (qPCR) assays revealed high transcription levels of cry10Aa in both T 0 GM cotton leaf and flower bud tissues. Southern blot and qPCR-based 2 -ΔΔCt analyses revealed that T 0 GM plants had either one or two transgene copies. Quantitative and qualitative analyses of Cry10Aa protein expression showed variable protein expression levels in both flower buds and leaves tissues of T 0 GM cotton plants, ranging from approximately 3.0 to 14.0 μg g -1 fresh tissue. CBW susceptibility bioassays, performed by feeding adults and larvae with T 0 GM cotton leaves and flower buds, respectively, demonstrated a significant entomotoxic effect and a high level of CBW mortality (up to 100%). Molecular analysis revealed that transgene stability and entomotoxic effect to CBW were maintained in T 1 generation as the Cry10Aa toxin expression levels remained high in both tissues, ranging from 4.05 to 19.57 μg g -1 fresh tissue, and the CBW mortality rate remained around 100%. In conclusion, these Cry10Aa GM cotton plants represent a great advance in the control of the devastating CBW insect pest and can substantially impact cotton agribusiness. © 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  3. Boll weevil within season and off-season activity monitored using a pheromone-and-glue reusable tube trap

    Directory of Open Access Journals (Sweden)

    Robério Carlos dos Santos Neves

    Full Text Available ABSTRACT: The boll weevil colonizes cotton fields as early as cotton squaring, causing significant losses due to feeding and protected development inside fruiting structures throughout crop phenology. Successful control depends on control of adults and their accurate detection when they colonize the crops. The commercial trap and boll weevil attract-and-control tubes (BWACT are the only available tools to monitor and attract-and-kill boll weevil, despite limitation in efficacy, and insecticide in BWACT is not allowed in organic production. A grandlure-and-glue reusable and insecticide-free tube (GGT made with polyvinyl chloride tube, smeared with entomological glue, and lured with pheromone was tested to detect boll weevil activity across various seasons. Boll weevil showed activity during growing season and off-season from 2009 to 2012 in the Semiarid and with higher numbers captured in GGT in comparisons to commercial traps. GGT was able to detect early weevils in the field right after planting. Further, the overall averages resulted in 34-, 16.8-, and 7.5-times more weevils captured in GGTs compared to the traps during stalk destruction in the Semiarid 2011 and Cerrado season 2012/13 and during the harvesting period in the Cerrado season 2011/12, respectively. Therefore, boll weevils were captured actively during season and off-season and early captures obtained in GGT compared to traps showed a better correlation between captures and square damage.

  4. Effects of Soil Water Deficit on Insecticidal Protein Expression in Boll Shells of Transgenic Bt Cotton and the Mechanism

    Directory of Open Access Journals (Sweden)

    Xiang Zhang

    2017-12-01

    Full Text Available This study was conducted to investigate the effects of soil water deficit on insecticidal protein expression in boll shells of cotton transgenic for a Bt gene. In 2014, Bt cotton cultivars Sikang 1 (a conventional cultivar and Sikang 3 (a hybrid cultivar were planted in pots and five soil water content treatments were imposed at peak boll stage: 15% (G1, 35% (G2, 40% (G3, 60% (G4, and 75% field capacity (CK, respectively. Four treatments (G2, G3, G4, and CK were repeated in 2015 in the field. Results showed that the insecticidal protein content of boll shells decreased with increasing water deficit. Compared with CK, boll shell insecticidal protein content decreased significantly when soil water content was below 60% of maximum water holding capacity for Sikang 1 and Sikang 3. However, increased Bt gene expression was observed when boll shell insecticidal protein content was significantly reduced. Activity assays of key enzymes in nitrogen metabolism showed that boll shell protease and peptidase increased but nitrogen reductase and glutamic-pyruvic transaminase (GPT decreased. Insecticidal protein content exhibited significant positive correlation with nitrogen reductase and GPT activities; and significant negative correlation with protease and peptidase activities. These findings suggest that the decrease of insecticidal protein content associated with increasing water deficit was a net result of decreased synthesis and increased decomposition.

  5. Transcriptome analysis of Gossypium hirsutum flower buds infested by cotton boll weevil (Anthonomus grandis) larvae.

    Science.gov (United States)

    Artico, Sinara; Ribeiro-Alves, Marcelo; Oliveira-Neto, Osmundo Brilhante; de Macedo, Leonardo Lima Pepino; Silveira, Sylvia; Grossi-de-Sa, Maria Fátima; Martinelli, Adriana Pinheiro; Alves-Ferreira, Marcio

    2014-10-04

    Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton boll weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton boll weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with boll weevil larvae. The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with boll weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to boll weevil larvae feeding was determined by "in situ" qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These

  6. Examination of the Abscission-Associated Transcriptomes for Soybean, Tomato, and Arabidopsis Highlights the Conserved Biosynthesis of an Extensible Extracellular Matrix and Boundary Layer.

    Science.gov (United States)

    Kim, Joonyup; Sundaresan, Srivignesh; Philosoph-Hadas, Sonia; Yang, Ronghui; Meir, Shimon; Tucker, Mark L

    2015-01-01

    Abscission zone (AZ) development and the progression of abscission (detachment of plant organs) have been roughly separated into four stages: first, AZ differentiation; second, competence to respond to abscission signals; third, activation of abscission; and fourth, formation of a protective layer and post-abscission trans-differentiation. Stage three, activation of abscission, is when changes in the cell wall and extracellular matrix occur to support successful organ separation. Most abscission research has focused on gene expression for enzymes that disassemble the cell wall within the AZ and changes in phytohormones and other signaling events that regulate their expression. Here, transcriptome data for soybean, tomato and Arabidopsis were examined and compared with a focus not only on genes associated with disassembly of the cell wall but also on gene expression linked to the biosynthesis of a new extracellular matrix. AZ-specific up-regulation of genes associated with cell wall disassembly including cellulases (beta-1,4-endoglucanases, CELs), polygalacturonases (PGs), and expansins (EXPs) were much as expected; however, curiously, changes in expression of xyloglucan endotransglucosylase/hydrolases (XTHs) were not AZ-specific in soybean. Unexpectedly, we identified an early increase in the expression of genes underlying the synthesis of a waxy-like cuticle. Based on the expression data, we propose that the early up-regulation of an abundance of small pathogenesis-related (PR) genes is more closely linked to structural changes in the extracellular matrix of separating cells than an enzymatic role in pathogen resistance. Furthermore, these observations led us to propose that, in addition to cell wall loosening enzymes, abscission requires (or is enhanced by) biosynthesis and secretion of small proteins (15-25 kDa) and waxes that form an extensible extracellular matrix and boundary layer on the surface of separating cells. The synthesis of the boundary layer

  7. Effect of raceme-localized supplemental light on soybean reproductive abscission

    International Nuclear Information System (INIS)

    Myers, R.L.; Brun, W.A.; Brenner, M.L.

    1987-01-01

    The percentage of soybean [Glycine max (L.) Merr.] reproductive structures that abscise is a potentially important yield factor. To better understand the involvement of light in the abscission of reproductive structures, a series of in vitro raceme-culture and growth-chamber experiments were conducted. In the in vitro raceme-culture experiments, racemes with four to six flowers at or past anthesis were excised from the soybean plant (genotype IX93-100), embedded in a complete nutrient, solid agar medium, and subjected to various light treatments. A series of three experiments indicated that the racemes contain a photoreceptor, possibly phytochrome, capable of regulating sucrose accumulation. In each of the growth chamber studies, supplemental light was supplied directly to individual soybean flowers via fiber optic light guides. The light source increased the photon flux to the flowers by 10-fold. The first growth chamber experiment showed that flowers receiving supplemental light were more intense sinks for 14 C-sucrose than were controls (intensity value of 1.0 vs 0.4 x 10 -7 , intensity = [dps of flower/dps of raceme]/[kg dry wt of flower]). In a second study, 42% of flowers treated with supplemental light set pods, while only 26% of control flowers set pods. A third experiment showed that red supplemental light produced 55% fruit set, compared to 41% set for far-red light, and 35% for controls. These experiments indicate that both photoassimilate accumulation and abscission in young soybean reproductive structures may be regulated by light quality

  8. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata

    Directory of Open Access Journals (Sweden)

    Michael F Cohen

    2015-07-01

    Full Text Available In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared (SR-FTIR spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

  9. Bimodal effect of hydrogen peroxide and oxidative events in nitrite-induced rapid root abscission by the water fern Azolla pinnata.

    Science.gov (United States)

    Cohen, Michael F; Gurung, Sushma; Birarda, Giovanni; Holman, Hoi-Ying N; Yamasaki, Hideo

    2015-01-01

    In the genus Azolla rapid abscission of roots from floating fronds occurs within minutes in response to a variety of stresses, including exposure to nitrite. We found that hydrogen peroxide, though itself not an inducer of root abscission, modulates nitrite-induced root abscission by Azolla pinnata in a dose-dependent manner, with 2 mM H2O2 significantly diminishing the responsiveness to 2 mM NaNO2, and 10 mM H2O2 slightly enhancing it. Hypoxia, which has been found in other plants to result in autogenic production of H2O2, dramatically stimulated root abscission of A. pinnata in response to nitrite, especially for plants previously cultivated in medium containing 5 mM KNO3 compared to plants cultivated under N2-fixing conditions without combined nitrogen. Plants, including Azolla, produce the small signaling molecule nitric oxide (NO) from nitrite using nitrate reductase. We found Azolla plants to display dose-dependent root abscission in response to the NO donor spermine NONOate. Treatment of plants with the thiol-modifying agents S-methyl methanethiosulfonate or glutathione inhibited the nitrite-induced root abscission response. Synchrotron radiation-based Fourier transform infrared spectromicroscopy revealed higher levels of carbonylation in the abscission zone of dropped roots, indicative of reaction products of polysaccharides with potent free radical oxidants. We hypothesize that metabolic products of nitrite and NO react with H2O2 in the apoplast leading to free-radical-mediated cleavage of structural polysaccharides and consequent rapid root abscission.

  10. Captures of Boll Weevils (Coleoptera: Curculionidae) in Relation to Trap Distance From Cotton Fields.

    Science.gov (United States)

    Spurgeon, Dale W

    2016-12-01

    The boll weevil (Anthonomus grandis grandis Boheman) has been eradicated from much of the United States, but remains an important pest of cotton (Gossypium spp.) in other parts of the Americas. Where the weevil occurs, the pheromone trap is a key tool for population monitoring or detection. Traditional monitoring programs have placed traps in or near the outermost cotton rows where damage by farm equipment can cause loss of trapping data. Recently, some programs have adopted a trap placement adjacent to but outside monitored fields. The effects of these changes have not been previously reported. Captures of early-season boll weevils by traps near (≤1 m) or far (7-10 m) from the outermost cotton row were evaluated. In 2005, during renewed efforts to eradicate the boll weevil from the Lower Rio Grande Valley of Texas, far traps consistently captured more weevils than traps near cotton. Traps at both placements indicated similar patterns of early-season weevil captures, which were consistent with those previously reported. In 2006, no distinction between trap placements was detected. Early-season patterns of captures in 2006 were again similar for both trap placements, but captures were much lower and less regular compared with those observed in 2005. These results suggest magnitude and likelihood of weevil capture in traps placed away from cotton are at least as high as for traps adjacent to cotton. Therefore, relocation of traps away from the outer rows of cotton should not negatively impact ability to monitor or detect the boll weevil. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by a US Government employee and is in the public domain in the US.

  11. Proteolytic processing of the vitellogenin precursor in the boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Heilmann, L J; Trewitt, P M; Kumaran, A K

    1993-01-01

    The soluble proteins of the eggs of the coleopteran insect Anthonomus grandis Boheman, the cotton boll weevil, consist almost entirely of two vitellin types with M(r)s of 160,000 and 47,000. We sequenced their N-terminal ends and one internal cyanogen bromide fragment of the large vitellin and compared these sequences with the deduced amino acid sequence from the vitellogenin gene. The results suggest that both the boll weevil vitellin proteins are products of the proteolytic cleavage of a single precursor protein. The smaller 47,000 M(r) vitellin protein is derived from the N-terminal portion of the precursor adjacent to an 18 amino acid signal peptide. The cleavage site between the large and small vitellins at amino acid 362 is adjacent to a pentapeptide sequence containing two pairs of arginine residues. Comparison of the boll weevil sequences with limited known sequences from the single 180,000 M(r) honey bee protein show that the honey bee vitellin N-terminal exhibits sequence homology to the N-terminal of the 47,000 M(r) boll weevil vitellin. Treatment of the vitellins with an N-glycosidase results in a decrease in molecular weight of both proteins, from 47,000 to 39,000 and from 160,000 to 145,000, indicating that about 10-15% of the molecular weight of each vitellin consists of N-linked carbohydrate. The molecular weight of the deglycosylated large vitellin is smaller than that predicted from the gene sequence, indicating possible further proteolytic processing at the C-terminal of that protein.

  12. Lethal and sublethal effects of selected insecticides and an insect growth regulator on the boll weevil (Coleoptera: Curculionidae) ectoparasitoid Catolaccus grandis (Hymenoptera: Pteromalidae).

    Science.gov (United States)

    Elzen, G W; Maldonado, S N; Rojas, M G

    2000-04-01

    A laboratory culture of Catolaccus grandis (Burks), an ectoparasitoid of the boll weevil, Anthonomus grandis grandis Boheman, was exposed to lethal and sublethal doses of insecticides and an insect growth regulator using a spray chamber bioassay. Materials tested were azinphos-methyl, endosulfan, fipronil, malathion, cyfluthrin, dimethoate, spinosad, methyl parathion, acephate, oxamyl, and tebufenozide. At full rates, spinosad was significantly less toxic to female C. grandis than other treatments except endosulfan. Fipronil and malathion were significantly more toxic to females than other treatments. Most of the chemicals tested were highly toxic to male C. grandis; spinosad was least toxic. At reduced rates, most of 4 selected chemicals tested were low in toxicity to C. grandis; however, a reduced rate of malathion was significantly more toxic to females than other treatments. No C. grandis pupae developed from parasitism during a 24-h treatment period with malathion or spinosad. The sex ratio of progeny from sprayed adults appeared to be unaffected by the treatments.

  13. Spatial and temporal distribution of cotton squares and small cotton bolls fallen on ground after damage by boll weevil and the efficiency of the equipment used to collect them

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Domingues da Silva

    Full Text Available ABSTRACT: In this study, we determined the spatial and temporal distribution of fallen cotton squares and small cotton bolls fallen damaged by boll weevil and the efficiency and time interval of the equipment used to collect cotton samples. Spatial and temporal distribution of cotton squares and small cotton bolls fallen on the soil damaged by boll weevil among cotton rows was determined in an experimental design of randomized blocks in a factorial arrangement of 4x3, represented by soil surface tracks located at 1-11cm, 12-22cm, 23-33cm, and 34-44cm away from the planting row of cotton plants 70, 85, and 100 days of age. Efficiency and collection time interval of the cotton samples fallen on the soil infested by boll weevil by plastic rakes that were straight or fan-shaped, big broom, collector instrument model CNPA and aspirator of leaves ‘Trapp’ were determined in randomized block design with five treatments, 10 repetitions for each. Results demonstrated that the collection of cotton samples must be performed with greater attention to soil strips located below the cotton top projection and aspirator ‘Trapp’ of leaves was more appropriate for the operation as it used less time of collection with similar efficiency to other available equipment.

  14. Floral organ abscission peptide IDA and its HAE/HSL2 receptors control cell separation during lateral root emergence

    OpenAIRE

    Kumpf, Robert P.; Shi, Chun-Lin; Larrieu, Antoine; Stø, Ida Myhrer; Butenko, Melinka A.; Péret, Benjamin; Riiser, Even Sannes; Bennett, Malcolm J.; Aalen, Reidunn B.

    2013-01-01

    Throughout their life cycle, plants produce new organs, such as leaves, flowers, and lateral roots. Organs that have served their purpose may be shed after breakdown of primary cell walls between adjacent cell files at the site of detachment. In Arabidopsis, floral organs abscise after pollination, and this cell separation event is controlled by the peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE) and HAESA-LI...

  15. Replication of Chilo iridescent virus in the cotton boll weevil, Anthonomus grandis, and development of an infectivity assay.

    Science.gov (United States)

    Henderson, C W; Johnson, C L; Lodhi, S A; Bilimoria, S L

    2001-01-01

    The boll weevil, Anthonomus grandis Boheman, is a devastating pest of cotton. Chemical pesticides are problematic due to relative lack of target specificity and resistance. Microbial pesticides may provide viable alternatives because of their narrow host range. Chilo iridescent virus (CIV) is the type species for genus Iridovirus, family Iridoviridae: large, icosahedral cytoplasmic viruses containing a double-stranded DNA genome. Earlier work suggested that CIV replicated in the boll weevil; however, efficiency or production of infectious virus was not established. We showed that CIV undergoes a productive cycle in A. grandis. CIV DNA levels in boll weevil pupae increased significantly from 0 to 3 days post infection. Moreover, virogenic stromata and complete virus particles were observed in the cytoplasm by 7 days. An endpoint dilution assay using viral DNA replication as indicator suggested a 10(5)-fold increase in infectious virus titer over 7 days. This is the first such demonstration in larval infections with genus Iridovirus. Our study establishes that CIV undergoes a productive cycle in the boll weevil and provides an important and useful model system for replication at the organismal level. These results have important implications for the potential of CIV and its components in boll weevil control.

  16. Transcriptome profiling of petal abscission zone and functional analysis of an Aux/IAA family gene RhIAA16 involved in petal shedding in rose

    Directory of Open Access Journals (Sweden)

    Yuerong Gao

    2016-09-01

    Full Text Available Roses are one of the most important cut flowers among ornamental plants. Rose flower longevity is largely dependent on the timing of petal shedding occurrence. To understand the molecular mechanism underlying petal abscission in rose, we performed transcriptome profiling of the petal abscission zone during petal shedding using Illumina technology. We identified a total of 2592 differentially transcribed genes (DTGs during rose petal shedding. Gene ontology term enrichment and pathway analysis revealed that major biochemical pathways the DTGs were involved in included ethylene biosynthesis, starch degradation, superpathway of cytosolic glycolysis, pyruvate dehydrogenase and TCA cycle, photorespiration and the lactose degradation III pathway. This suggests that alterations in carbon metabolism are an important part of rose petal abscission. Among these DTGs, approximately 150 genes putatively encoding transcription factors were identified in rose abscission zone. These included zinc finger, WRKY, ERF, and Aux/IAA gene families, suggesting that petal abscission involves complex transcriptional reprogramming. Approximately 108 DTGs were related to hormone pathways, of which auxin and ethylene related DTGs were the largest groups including 52 and 41 genes, respectively. These also included 12 DTGs related to gibberellin and 6 DTGs in jasmonic acid pathway. Surprisingly, no DTGs involved in the biosynthesis/signaling of abscisic acid, cytokinin, brassinosteroid, and salicylic acid pathways were detected. Moreover, among DTGs related to auxin, we identified an Aux/IAA gene RhIAA16 that was up-regulated in response to petal shedding. Down-regulation of RhIAA16 by virus-induced gene silencing in rose promoted petal abscission, suggesting that RhIAA16 plays an important role in rose petal abscission.

  17. TBCD links centriologenesis, spindle microtubule dynamics, and midbody abscission in human cells.

    Directory of Open Access Journals (Sweden)

    Mónica López Fanarraga

    2010-01-01

    Full Text Available Microtubule-organizing centers recruit alpha- and beta-tubulin polypeptides for microtubule nucleation. Tubulin synthesis is complex, requiring five specific cofactors, designated tubulin cofactors (TBCs A-E, which contribute to various aspects of microtubule dynamics in vivo. Here, we show that tubulin cofactor D (TBCD is concentrated at the centrosome and midbody, where it participates in centriologenesis, spindle organization, and cell abscission. TBCD exhibits a cell-cycle-specific pattern, localizing on the daughter centriole at G1 and on procentrioles by S, and disappearing from older centrioles at telophase as the protein is recruited to the midbody. Our data show that TBCD overexpression results in microtubule release from the centrosome and G1 arrest, whereas its depletion produces mitotic aberrations and incomplete microtubule retraction at the midbody during cytokinesis. TBCD is recruited to the centriole replication site at the onset of the centrosome duplication cycle. A role in centriologenesis is further supported in differentiating ciliated cells, where TBCD is organized into "centriolar rosettes". These data suggest that TBCD participates in both canonical and de novo centriolar assembly pathways.

  18. Involvement of abscisic acid in correlative control of flower abscission in soybean

    International Nuclear Information System (INIS)

    Yarrow, G.L.

    1985-01-01

    Studies were carried out in three parts: (1) analysis of endogenous abscisic acid (ABA) in abscising and non-abscising flowers, (2) partitioning of radio-labelled ABA and photoassimilates within the soybean raceme, and (3) shading experiments, wherein endogenous levels, metabolism and partitioning of ABA were determined. Endogenous concentrations of ABA failed to show any consistent relationship to abscission of soybean flowers. Partitioning of radiolabelled ABA and photoassimilates displayed consistently higher sink strengths (% DPM) for both 3 H-ABA and 14 C-photoassimilates for non-abscising flowers than for abscising flowers within control racemes. Shading flowers with aluminum foil, 48 hrs prior to sampling, resulted in lowered endogenous ABA concentrations at 12, 17 and 22 days after anthesis (DAA), but not at 0 or 4 DAA. No differences were found in the catabolism of 3 H-ABA between shaded (abscising) and non-shaded (non-abscising) flowers. Reduced partitioning of ABA and photoassimilates to shaded flowers resulted when shades were applied at 0, 4, 12, and 17 DAA, but not at 22 DAA

  19. Abscission Layer Formation as a Resistance Response of Peruvian Apple Cactus Against Glomerella cingulata.

    Science.gov (United States)

    Kim, Young Ho; Kim, Kwang-Hyung

    2002-09-01

    ABSTRACT Stem disks from 2-year-old cacti Cereus tetragonus (susceptible) and C. peruvianus (resistant) were inoculated in the center (pith) with Glomerella cingulata isolated from Colletotrichum stem rot in three-angled cacti. The susceptible cactus became extensively colonized, whereas colonization was limited to a small area in the resistant cactus. The resistant cactus formed prominent abscission layers (ALs) in parenchyma internal to the inoculation site. Ethanol extracts of the fungal culture also stimulated AL formation in the resistant cactus. Initial cell division followed at 2 to 4 days after treatment, and layering of multiple cells at 7 days after treatment. After 10 days, the outer layers were sometimes sloughed from the inner layers. No AL formation was induced in susceptible C. tetragonus treated with ethanol extract or in untreated control cacti. Light and electron microscopy revealed that initial cell division occurred by cell wall formation, and that an additional cell wall was layered in pre-existing parenchyma cells without ordinary cell division. Later, separation layers formed in ALs where inner cell walls appeared to be thickened secondarily, and the cell walls and middle lamella within the layer dissolved. These results suggest that AL formation in the resistant cactus is induced by fungal metabolites, and that it serves as a histological barrier against anthracnose pathogens.

  20. Transfection of cultured cells of the cotton boll weevil, Anthonomus grandis, with a heat-shock-promoter-chloramphenicol-acetyltransferase construct.

    Science.gov (United States)

    Stiles, B; Heilmann, J; Sparks, R B; Santoso, A; Leopold, R A

    1992-01-01

    Expression of heat shock proteins (hsp) in the BRL-AG-3C cell line from the cotton boll weevil was examined. It was determined that the maximal expression of endogenous hsp occurred at 41 degrees C. Various transfection methods were then compared using this cell line in conjunction with a transiently expressed bacterial gene marker (chloramphenicol acetyltransferase) which was under the control of the Drosophila hsp 70 gene promoter. The cationic lipid preparation Lipofectin was found to be very efficient at transfecting the boll weevil cells. Polylysine and 20-hydroxyecdysone-conjugated polylysine were moderately effective, whereas polybrene and electroporation, under the conditions reported herein, were ineffective at transfecting this cell line.

  1. A model for long-distance dispersal of boll weevils (Coleoptera: Curculionidae)

    Science.gov (United States)

    Westbrook, John K.; Eyster, Ritchie S.; Allen, Charles T.

    2011-07-01

    The boll weevil, Anthonomus grandis (Boheman), has been a major insect pest of cotton production in the US, accounting for yield losses and control costs on the order of several billion US dollars since the introduction of the pest in 1892. Boll weevil eradication programs have eliminated reproducing populations in nearly 94%, and progressed toward eradication within the remaining 6%, of cotton production areas. However, the ability of weevils to disperse and reinfest eradicated zones threatens to undermine the previous investment toward eradication of this pest. In this study, the HYSPLIT atmospheric dispersion model was used to simulate daily wind-aided dispersal of weevils from the Lower Rio Grande Valley (LRGV) of southern Texas and northeastern Mexico. Simulated weevil dispersal was compared with weekly capture of weevils in pheromone traps along highway trap lines between the LRGV and the South Texas / Winter Garden zone of the Texas Boll Weevil Eradication Program. A logistic regression model was fit to the probability of capturing at least one weevil in individual pheromone traps relative to specific values of simulated weevil dispersal, which resulted in 60.4% concordance, 21.3% discordance, and 18.3% ties in estimating captures and non-captures. During the first full year of active eradication with widespread insecticide applications in 2006, the dispersal model accurately estimated 71.8%, erroneously estimated 12.5%, and tied 15.7% of capture and non-capture events. Model simulations provide a temporal risk assessment over large areas of weevil reinfestation resulting from dispersal by prevailing winds. Eradication program managers can use the model risk assessment information to effectively schedule and target enhanced trapping, crop scouting, and insecticide applications.

  2. Chitinolitic activity in proteic extracts of Bacillus thuringiensis toxic to boll weevil (Anthonomus grandis)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, T.S; Rocha, T.L. [EMBRAPA Recursos Geneticos e Biotecnologia, DF (Brazil); Vasconcelos, E.A.R [Universidade de Brasilia (UnB), DF (Brazil); Grossi-de-Sa, M.F. [Universidade Catolica de Brasilia, DF (Brazil)

    2008-07-01

    Full text: Bacillus thuringiensis (Bt) is a spore forming bacteria, which produces Cry proteins toxic towards several insect orders. Bt S 811 strain produces at least three Cry toxins: Cry1Ab, Cry1Ia12, and Cry8, and shown toxicity to insects from Coleoptera order. In order to characterize the production of theses toxins, and check its activity against Boll weevil larvae, proteic extracts from Bt cells and supernatant proteins from the bacterial culture, were obtained at different stages of cell cycle; 8, 16, 24, and 32 hours after inoculation (HAI). Proteins from 32 HAI of the supernatant, and 8 HAI of the cellular fractions, shown highest activity towards the Boll weevil larvae. Western blotting assays using anti-Cry8 and anti-Cry1I were carried out to analyse these toxins in the Bt proteic extracts. The existence of a Cry8 was detected at 8 HAI in the cellular fraction, what allow associate this molecule with the toxicity of this fraction. However, toxicity observed at 32 HAI in the supernatant fraction, was not possible to be associated with Cry8 or Cry1Ia toxins, indicating that there are another protein(s) responsible for the toxicity. A protein homo log to Cry1Ab was identified by 'Peptide Mass Fingerprint' at 32 HAI of the supernatant fraction and a chitin binding protein was identified by 2DE/MS/MS in this same stage and chitinolitic activity was also observed by enzymatic assay. All our data suggest a possible synergism between Cry toxins and a chitinase in the activity of this strain towards Boll weevil.

  3. Emissão/abscisão de estruturas reprodutivas do algodoeiro herbáceo, cv. CNPA 7H: efeito do estresse hídrico Emission/abscission of reproductive structures of herbaceous cotton, cv. CNPA 7H: effect of the water stress

    Directory of Open Access Journals (Sweden)

    Francineuma P. de Arruda

    2002-04-01

    Full Text Available O presente estudo foi conduzido no período de julho a dezembro de 1998, em galpão coberto, no DSER/CCA/UFPB, município de Areia, PB, com o objetivo de se avaliar o efeito dos níveis de água disponível no solo (AD (20, 40, 60 e 80% sobre a emissão/abscisão de estruturas reprodutivas do algodoeiro herbáceo, cv. CNPA 7H; utilizou-se delineamento experimental inteiramente casualizado, com quatro tratamentos e três repetições, em três épocas de amostragem. O crescimento vegetativo e o reprodutivo, aumentaram com os níveis de AD no solo, sendo a menor média de altura de plantas (34,5 cm, área foliar (633,05 cm², acumulação de fitomassa da parte aérea (9,04 g, botões florais (4,67, flores (3,50, maçãs (2,33 e capulhos (1,33 por planta, observada no tratamento com o nível de 20% da AD e a maior, 74,33 cm, 2.634,81cm², 24,86 g, 9,67, 7,0, 6,0 e 4,3 por planta, respectivamente, no tratamento com o nível de 60% da AD. Apesar do estresse hídrico ter afetado (pThe present study was conducted from July to December 1998, in a covered area at DSER/CCA/UFPB, Areia/PB with the objective of evaluating the effect of four levels of available water (AW - 20, 40, 60 and 80% in soil on the emission/abscission of reproductive structures of herbaceous cotton plant, cv. CNPA 7H. A completely randomized experimental design was used, with four treatments replicated three times and sampled at three different dates. Vegetative and reproductive growth increased with AW levels in soil. Minimum mean values for plant height (34.5 cm, leaf area (633.05 cm², biomass accumulation of aerial parts (9.04 g, number of flower buds (4.67, flowers (3.50, fruits (2.33 and bolls (1.33 per plant, were observed for the 20% AW treatment. In contrast, the highest mean values observed for the 60% AW treatment, respectively, were 74.33 cm, 2,634.8 cm², 24.86 g, 9.67, 7.0, 6.0 and 4.3. Water stress showed significant effect (p<0,05 on emission and abscission of

  4. Modification of carotenoid levels by abscission agents and expression of carotenoid biosynthetic genes in 'valencia' sweet orange.

    Science.gov (United States)

    Alferez, Fernando; Pozo, Luis V; Rouseff, Russell R; Burns, Jacqueline K

    2013-03-27

    The effect of 5-chloro-3-methyl-4-nitro-1H-pyrazole (CMNP) and ethephon on peel color, flavedo carotenoid gene expression, and carotenoid accumulation was investigated in mature 'Valencia' orange ( Citrus sinensis L. Osbeck) fruit flavedo at three maturation stages. Abscission agent application altered peel color. CMNP was more effective than ethephon in promoting green-to-red (a) and blue-to-yellow (b) color at the middle and late maturation stages and total carotenoid changes at all maturation stages. Altered flow of carotenoid precursors during maturation due to abscission agents was suggested by changes in phytoene desaturase (Pds) and ζ-carotene desaturase (Zds) gene expression. However, each abscission agent affected downstream expression differentially. Ethephon application increased β-carotene hydroxilase (β-Chx) transcript accumulation 12-fold as maturation advanced from the early to middle and late stages. CMNP markedly increased β- and ε-lycopene cyclase (Lcy) transcript accumulation 45- and 15-fold, respectively, at midmaturation. Patterns of carotenoid accumulation in flavedo were supported in part by gene expression changes. CMNP caused greater accumulation of total flavedo carotenoids at all maturation stages when compared with ethephon or controls. In general, CMNP treatment increased total red carotenoids more than ethephon or the control but decreased total yellow carotenoids at each maturation stage. In control fruit flavedo, total red carotenoids increased and yellow carotenoids decreased as maturation progressed. Trends in total red carotenoids during maturation were consistent with measured a values. Changes in carotenoid accumulation and expression patterns in flavedo suggest that regulation of carotenoid accumulation is under transcriptional, translational, and post-translational control.

  5. Olfaction in the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae): Electroantennogram studies.

    Science.gov (United States)

    Dickens, J C

    1984-12-01

    Electroantennogram (EAG) techniques were utilized to measure the antennal olfactory responsiveness of adult boll weevils,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to 38 odorants, including both insect and host plant (Gossypium hirsutum L.) volatiles. EAGs of both sexes were indicative of at least two receptor populations: one receptor population primarily responsive to pheromone components and related compounds, the other receptor population primarily responsive to plant odors. Similar responses to male aggregation pheromone components (i.e., compounds I, II, and III + IV) were obtained from both sexes, but females were slightly more sensitive to I. Both sexes were highly responsive to components of the "green leaf volatile complex," especially the six-carbon saturated and monounsaturated primary alcohols. Heptanal was the most active aldehyde tested. More acceptors responded to oxygenated monoterpenes than to monoterpene hydrocarbons. β-Bisabolol, the major volatile of cotton, was the most active sesquiterpene. In general, males, which are responsible for host selection and pheromone production, were more sensitive to plant odors than were females. In fact, males were as sensitive to β-bisabolol and heptanal as to aggregation pheromone components. Electrophysiological data are discussed with regard to the role of insect and host plant volatiles in host selection and aggregation behavior of the boll weevil.

  6. Feeding deterrent compounds to the boll weevil,Anthonomus grandis Boheman in Rose-of-Sharon,Hibiscus syriacus L.

    Science.gov (United States)

    Bird, T G; Hedin, P A; Burks, M L

    1987-05-01

    The Rose-of-Sharon,Hibiscus syriacus (L.), can be a significant alternate host plant for the boll weevil,Anthonomus gradis (Boh.). Boll weevils are known to be deterred from feeding and ovipositing in the buds unless the calyx is removed. This investigation was initiated to identify calyx allelochemicals that deter feeding with the eventual strategy of breeding for cotton lines high in these allelochemicals in the appropriate tissues. The feeding deterrency of calyx tissue from the buds of Rose-of-Sharon for the boll weevil was confirmed. The most active deterrent fraction was found to contain mostly fatty acids and their methyl esters. Saturated fatty acids and their methyl esters were generally found to be stimulatory, while the unsaturated species were found to be deterrent. Higher quantities of the fatty acids, particularly the unsaturated species, were found in Rose-of-Sharon calyx tissue than in the buds without calyx. This supports the hypothesis developed through the isolational work and testing of standards that the unsaturated fatty acids are significant deterrents of boll weevil feeding.

  7. Temporal changes in genetic variation of boll weevil (Coleoptera: Curculionidae) populations, and implications for population assignment in eradication zones

    Science.gov (United States)

    Genetic differentiation among 10 populations of boll weevil, Anthonomus grandis grandis, sampled in 2009, in Texas and Mexico, was determined using ten microsatellite loci. In addition, temporal changes in genetic composition were examined in the eight populations for which samples were available fr...

  8. Efficacy of the organic-certified insecticide Diatect II against the boll weevil (Anthonomus grandis) in cotton.

    Science.gov (United States)

    Sappington, Thomas W

    2002-10-01

    The efficacy of the organic insecticide Diatect II against boll weevil (Anthonomus grandis Boheman) in cotton (Gossypium hirsutum L) in the Lower Rio Grande Valley of Texas were assessed in small-plot field trials and greenhouse cage tests using azinphos-methyl treatments as a standard for comparison. Plastic sheets were placed in the furrows of the treated plots to retrieve boll weevils which dropped from the plants after being killed by the insecticides. Samples of live weevils taken by a tractor-mounted vacuum sampler revealed a modest, but significant, reduction in boll weevil populations in Diatect II plots. However, samples of dead weevils indicated that this reduction was due to movement of weevils out of the plots rather than to mortality. This interpretation is supported by greenhouse cage studies, where mortality in Diatect II treated cages was no greater than that in untreated control cages. The effects of insecticide treatments in small plots can be confounded easily and quickly by interplot movement of target insects. Although the relative effects of various compounds can usually be assessed by sampling the populations in plots soon after treatment, the best measure of efficacy is obtained by directly sampling insects that have died in the plot. This parameter is insulated from the effects of interplot movement, unless the toxicant is slow to immobilize the target insect. Taken together, our results indicate little efficacy by Diatect II against boll weevil under our test conditions.

  9. Population structure and genetic diversity of the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), on Gossypium in North America

    Science.gov (United States)

    While the boll weevil, Anthonomus grandis, has been identified as one of the most devastating pests in U.S. history, its origin and activity in Mexico, both on wild and cultivated cotton hosts (genus Gossypium), is poorly understood. Three forms (geographical or host-associated races) of A. grandis ...

  10. Molecular cloning of a cysteine proteinase cDNA from the cotton boll weevil Anthonomus grandis (Coleoptera: Curculionidae).

    Science.gov (United States)

    De Oliveira Neto, Osmundo Brilhante; Batista, João Aguiar Nogueira; Rigden, Daniel John; Franco, Octávio Luiz; Fragoso, Rodrigo Rocha; Monteiro, Ana Carolina Santos; Monnerat, Rose Gomes; Grossi-De-Sa, Maria Fátima

    2004-06-01

    The cotton boll weevil (Anthonomus grandis) causes severe cotton crop losses in North and South America. This report describes the presence of cysteine proteinase activity in the cotton boll weevil. Cysteine proteinase inhibitors from different sources were assayed against total A. grandis proteinases but, unexpectedly, no inhibitor tested was particularly effective. In order to screen for active inhibitors against the boll weevil, a cysteine proteinase cDNA (Agcys1) was isolated from A. grandis larvae using degenerate primers and rapid amplification of cDNA ends (RACE) techniques. Sequence analysis showed significant homologies with other insect cysteine proteinases. Northern blot analysis indicated that the mRNA encoding the proteinase was transcribed mainly in the gut of larvae. No mRNA was detected in neonatal larvae, pupae, or in the gut of the adult insect, suggesting that Agcys1 is an important cysteine proteinase for larvae digestion. The isolated gene will facilitate the search for highly active inhibitors towards boll weevil larvae that may provide a new opportunity to control this important insect pest.

  11. Effect of temperature on the reproduction of Bracon vulgaris Ashmead (Hymenoptera: Braconidae, a parasitoid of the cotton boll weevil

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    Francisco S. Ramalho

    2011-09-01

    Full Text Available This research studied the effect of temperature on the reproduction of Bracon vulgaris Ashmead, an ectoparasitoid of cotton boll weevil ( Anthonomus grandis Boheman at constant temperatures of 20, 25 and 30ºC, 70 ± 10% RH and a photophase of 14 h. Females of the parasitoid produced a greater number of eggs when exposed to 25ºC (124.65 eggs in relation to those exposed to 20 (43.40 eggs and 30ºC (49.60 eggs. The number of parasitized larvae per female of B. vulgaris at 25ºC (71.75 was greater than at 20ºC (31.40 and 30ºC (25.15. The daily intrinsic rates of increase (r m were - 0.007 at 20ºC, 0.07 at 25ºC and 0.03 at 30ºC, revealing that the temperature of 25ºC produced increases of 1,100 and 133% in the value r m in relation to temperatures of 20 and 30ºC, respectively. In programs of biological control of the boll weevil using innoculative releases, adult females of B. vulgaris with approximately five (at 25 or 30ºC or 20 day old (at 20ºC should be used; when using innundative releases, adult females of B. vulgaris , with ages between 11 and 31; 9 and 29 or 3 and 14 days, respectively, at 20, 25 or 30ºC should be used.Estudamos os efeitos da temperatura na reprodução de Bracon vulgaris Ashmead, ectoparasitóide do bicudo-do-algodoeiro, Anthonomus grandis Boheman, em câmaras climatizadas, em temperaturas constantes de 20, 25 and 30ºC, umidade relativa do ar de 70 ± 10% e fotofase de 14 h. As fêmeas do parasitóide produziram mais ovos a 25ºC (124,65 ovos do que aquelas expostas a 20 (43,40 ovos e a 30ºC (49,60 ovos. O número médio de larvas parasitadas por fêmea de B. vulgaris a 25ºC(71,75 larvas foi maior do que a 20ºC (31,40 larvas e 30ºC (25,15 larvas. As taxas diárias de aumento (r m foram -0,007 a 20ºC, 0,07 a 25ºC e 0,03 a 30ºC, indicando que a temperatura de 25ºC produziu aumento de 1100 e 133% no valor de r m em relação às temperaturas de 20 e 30ºC, respectivamente. Nos programas de controle biol

  12. Are we on the right track: Can our understanding of abscission in model systems promote or derail making improvements in less studied crops

    Science.gov (United States)

    As the world population grows and resources and climate conditions change, crop improvement continues to be one of the most important challenges for agriculturalists. The yield and quality of many crops is affected by abscission or shattering, and environmental stresses often hasten or alter the abs...

  13. Pollination increases ethylene production in Lilium hybrida cv. Brindisi flowers but does not affect the time to tepal senescence or tepal abscission.

    Science.gov (United States)

    Pacifici, Silvia; Prisa, Domenico; Burchi, Gianluca; van Doorn, Wouter G

    2015-01-15

    In many species, pollination induces a rapid increase in ethylene production, which induces early petal senescence, petal abscission, or flower closure. Cross-pollination in Lilium hybrida cv. Brindisi resulted in a small increase in flower ethylene production. In intact plants and in isolated flowers, pollination had no effect on the time to tepal senescence or tepal abscission. When applied to closed buds of unpollinated flowers, exogenous ethylene slightly hastened the time to tepal senescence and abscission. However, exogenous ethylene had no effect when the flowers had just opened, i.e. at the time of pollination. Experiments with silver thiosulphate, which blocks the ethylene receptor, indicated that endogenous ethylene had a slight effect on the regulation of tepal senescence and tepal abscission, although only at the time the tepals were still inside buds and not in open flowers. Low ethylene-sensitivity after anthesis therefore explains why pollination had no effect on the processes studied. Copyright © 2014 Elsevier GmbH. All rights reserved.

  14. Cholesterol oxidase interference on the emergence and viability of cotton boll weevil larvae

    Directory of Open Access Journals (Sweden)

    Santos Roseane Cavalcanti

    2002-01-01

    Full Text Available The aim of this work was to evaluate the influence of the enzyme cholesterol oxidase (Coase on emergence and viability of larvae of the cotton boll weevil (Anthonomus grandis Boheman, 1843. A series of bioassays was performed with eggs and neonate larvae exposed to different enzyme concentrations in artificial diet. Larval survival was affected at all enzyme concentrations tested, and the six-day LD50 was 53 mug/mL (CI 95%: 43-59. Coase also interfered with hatching of larvae after eggs were floated for 15 min in Coase solution at different concentrations. Observations at the light and electronic microscopic level of midguts from larvae fed on artificial diet containing 53 mug/mL of Coase and collected at six days revealed highly vacuolated regions in the epithelial cells as well as partial degradation of the basal membrane and microvilli.

  15. Sterilization of boll weevil pupae with fractionated doses of gamma irradiation

    International Nuclear Information System (INIS)

    Haynes, J.W.; Mitlin, N.; Davich, T.B.; Dawson, J.R.; McGovern, W.L.; McKibben, G.H.

    1977-01-01

    Fractionated doses of 6,250-8,000 rads of gamma irradiation administered to pupae of the boll weevil, Anthonomus grandis Boh., sexually sterilized both sexes. Mortality of males thus treated with 6,250 and 8,000 rads via fractionation was 14% and 27% respectively, by 5 days posttreatment compared with 46% mortality when an equivalent acute dose was administered to newly emerged adults. Pheromone production of males irradiated at 6,250 rads was one-third that of the control for the first 4 days, but equal that of the control during 5-11 days posttreatment. This procedure lends itself to the large-scale sterilization of weevils needed in an eradication program. This technique is applicable to other insects that are highly susceptible to acute doses

  16. Fractionated vs acute irradiation: the effects of treating adult boll weevils (Coleoptera: Curculionidae) at different ages

    International Nuclear Information System (INIS)

    Haynes, J.W.; Wright, J.E.; Mattix, E.

    1979-01-01

    When 6-7 days old mass-reared ebony boll weevils, Anthonomus grandis Boheman, were given 25 doses of γ-irradiation totaling 6625 rads, mortality was 14%-15% less 1 week later than when young weevils (1-2 day-old) were similarly treated. However, giving older weevils an acute dose of 6625 rads did not reduce mortality. Seven-day-old weevils receiving the acute treatment mated 10% more than weevils that were 3 days old at the time of treatment. Seven-day-old male weevils exposed to the fractionated treatment transferred sperm to 12% more females than 7-day-old males exposed to the acute treatment. (Auth.)

  17. Nucleases as a barrier to gene silencing in the cotton boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Almeida Garcia, Rayssa; Lima Pepino Macedo, Leonardo; Cabral do Nascimento, Danila; Gillet, François-Xavier; Moreira-Pinto, Clidia Eduarda; Faheem, Muhammad; Moreschi Basso, Angelina Maria; Mattar Silva, Maria Cristina; Grossi-de-Sa, Maria Fatima

    2017-01-01

    RNA interference (RNAi) approaches have been applied as a biotechnological tool for controlling plant insect pests via selective gene down regulation. However, the inefficiency of RNAi mechanism in insects is associated with several barriers, including dsRNA delivery and uptake by the cell, dsRNA interaction with the cellular membrane receptor and dsRNA exposure to insect gut nucleases during feeding. The cotton boll weevil (Anthonomus grandis) is a coleopteran in which RNAi-mediated gene silencing does not function efficiently through dsRNA feeding, and the factors involved in the mechanism remain unknown. Herein, we identified three nucleases in the cotton boll weevil transcriptome denoted AgraNuc1, AgraNuc2, and AgraNuc3, and the influences of these nucleases on the gene silencing of A. grandis chitin synthase II (AgraChSII) were evaluated through oral dsRNA feeding trials. A phylogenetic analysis showed that all three nucleases share high similarity with the DNA/RNA non-specific endonuclease family of other insects. These nucleases were found to be mainly expressed in the posterior midgut region of the insect. Two days after nuclease RNAi-mediated gene silencing, dsRNA degradation by the gut juice was substantially reduced. Notably, after nucleases gene silencing, the orally delivered dsRNA against the AgraChSII gene resulted in improved gene silencing efficiency when compared to the control (non-silenced nucleases). The data presented here demonstrates that A. grandis midgut nucleases are effectively one of the main barriers to dsRNA delivery and emphasize the need to develop novel RNAi delivery strategies focusing on protecting the dsRNA from gut nucleases and enhancing its oral delivery and uptake to crop insect pests.

  18. Residues of Malathion and Metabolites in and on the Cotton Leaf vs. Toxicity to the Boll Weevil

    Science.gov (United States)

    D.A. Wolfenbarger

    2002-01-01

    Malathion was applied at 12 and 16 oz [A.l.]/a to cotton near Mercedes, TX, in 1995 and sampled on 0, 2, 4 and 6 d posttreatment to determine residues of malathion, malaoxon, and iso-malathion. Residues were then compared to determine toxicity to boll weevil, Anthonomus grandis Boheman. Residues of malathion comprised 99% of the leaf washes and 100% of the leaf...

  19. Between-season attraction of cotton boll weevil, Anthonomus grandis Boh. (Coleoptera: Curculionidae adults by its aggregation pheromone

    Directory of Open Access Journals (Sweden)

    Fernandes Wedson Desidério

    2001-01-01

    Full Text Available The present study was undertaken to investigate the attractiveness of boll weevil adults by its aggregation pheromone under winter field conditions. Two experimental fields were utilized at "Casa Branca", SP, Brazil. For each one, three areas were established near the refuge vegetation, sparated 500 m from each other. Each area was divided in three sub-areas or blocks of 100 m² to receive pheromone applications (2.5 g per block. In addition to the pre-application counting, five additional evaluations were carried out after the pheromone applicaton. Ten randomized sampling points per block were considered in each evaluation process. A. grandis adults responded immediately to the pheromone applications, and were captured for 14 days . The highest level of attractiveness was observed 24 hours after application. The application of the boll weevil aggregation pheromone during winter could increase the predation by natural enemies, due to the increase of prey availability. Chemical control can be recommended 24 hours after pheromone applications in small plots as a between-season strategy for the suppression of boll weevil adults.

  20. Floral organ abscission peptide IDA and its HAE/HSL2 receptors control cell separation during lateral root emergence.

    Science.gov (United States)

    Kumpf, Robert P; Shi, Chun-Lin; Larrieu, Antoine; Stø, Ida Myhrer; Butenko, Melinka A; Péret, Benjamin; Riiser, Even Sannes; Bennett, Malcolm J; Aalen, Reidunn B

    2013-03-26

    Throughout their life cycle, plants produce new organs, such as leaves, flowers, and lateral roots. Organs that have served their purpose may be shed after breakdown of primary cell walls between adjacent cell files at the site of detachment. In Arabidopsis, floral organs abscise after pollination, and this cell separation event is controlled by the peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE) and HAESA-LIKE2 (HSL2). Emergence of new lateral root primordia, initiated deep inside the root under the influence of auxin, is similarly dependent on cell wall dissolution between cells in the overlaying endodermal, cortical, and epidermal tissues. Here we show that this process requires IDA, HAE, and HSL2. Mutation in these genes constrains the passage of the growing lateral root primordia through the overlaying layers, resulting in altered shapes of the lateral root primordia and of the overlaying cells. The HAE and HSL2 receptors are redundant in function during floral organ abscission, but during lateral root emergence they are differentially involved in regulating cell wall remodeling genes. In the root, IDA is strongly auxin-inducible and dependent on key regulators of lateral root emergence--the auxin influx carrier LIKE AUX1-3 and AUXIN RESPONSE FACTOR7. The expression levels of the receptor genes are only transiently induced by auxin, suggesting they are limiting factors for cell separation. We conclude that elements of the same cell separation signaling module have been adapted to function in different developmental programs.

  1. The Effect of Rate and Application Method of Potassium on Yield and Yield Components of Cotton in Saline Condition

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    A Ardakani

    2016-12-01

    Full Text Available Introduction Salinity is a major abiotic stress that affects approximately 7% of the world’s total land area. Cotton (Gossypium barbadense L. is considered as one of the most important cash crops which is widely used for agricultural and industrial purposes. Although, cotton is classified as one of the most salt-tolerant major crops but its growth and development are adversely affected by soil or water salinity. Understanding salinity and fertilizer interaction can mitigate salinity stress and improving crop yield. Potassium (K is an essential nutrient that affects most of the biochemical and physiological processes that are involved in plant resistance to biotic and abiotic stresses. Proper management of K fertilizer is especially important in saline soils where K application might reduce the adverse effects of salinity on plant growth and yield. There is a little information about rate and application method of K on yield and yield component of cotton in saline condition. The objective of this study was to determine the effects of rate and application method of K on yield and yield component of cotton in soil and water saline condition. Materials and Methods The experiment was carried out at Sabzevar Agriculture and Natural Resources Research center (Haresabad, 30km southwest of Sabzevar (32◦32N, 51◦23E and 1630 above mean sea level,in 2014.This experiment was conducted as split plot design based on randomized complete block design with three replications. Factors were: K rate (75 and 150kg ha-1 Solopotash (containing 50% K2O and 18% S comprising the main plot and application method (25%at planting+25% at first flowering and 50%at early boll development (25P+25F+50B, 25%at planting+50% at first flowering and 25%at early boll development (25P+50F+25B, 25%at planting+25% at vegetative stage (5-8 leaves stage, 25% at first flowering and 25% at early boll development (25P+25V+25F+50B, 25% at planting+25% at vegetative stage and 50% at first

  2. Single and multiple in-season measurements as indicators of at-harvest cotton boll damage caused by verde plant bug (Hemiptera: Miridae).

    Science.gov (United States)

    Brewer, Michael J; Armstrong, J Scott; Parker, Roy D

    2013-06-01

    The ability to monitor verde plant bug, Creontiades signatus Distant (Hemiptera: Miridae), and the progression of cotton, Gossypium hirsutum L., boll responses to feeding and associated cotton boll rot provided opportunity to assess if single in-season measurements had value in evaluating at-harvest damage to bolls and if multiple in-season measurements enhanced their combined use. One in-season verde plant bug density measurement, three in-season plant injury measurements, and two at-harvest damage measurements were taken in 15 cotton fields in South Texas, 2010. Linear regression selected two measurements as potentially useful indicators of at-harvest damage: verde plant bug density (adjusted r2 = 0.68; P = 0.0004) and internal boll injury of the carpel wall (adjusted r2 = 0.72; P = 0.004). Considering use of multiple measurements, a stepwise multiple regression of the four in-season measurements selected a univariate model (verde plant bug density) using a 0.15 selection criterion (adjusted r2 = 0.74; P = 0.0002) and a bivariate model (verde plant bug density-internal boll injury) using a 0.25 selection criterion (adjusted r2 = 0.76; P = 0.0007) as indicators of at-harvest damage. In a validation using cultivar and water regime treatments experiencing low verde plant bug pressure in 2011 and 2012, the bivariate model performed better than models using verde plant bug density or internal boll injury separately. Overall, verde plant bug damaging cotton bolls exemplified the benefits of using multiple in-season measurements in pest monitoring programs, under the challenging situation when at-harvest damage results from a sequence of plant responses initiated by in-season insect feeding.

  3. Stable integration and expression of a cry1Ia gene conferring resistance to fall armyworm and boll weevil in cotton plants.

    Science.gov (United States)

    Silva, Carliane Rc; Monnerat, Rose; Lima, Liziane M; Martins, Érica S; Melo Filho, Péricles A; Pinheiro, Morganna Pn; Santos, Roseane C

    2016-08-01

    Boll weevil is a serious pest of cotton crop. Effective control involves applications of chemical insecticides, increasing the cost of production and environmental pollution. The current genetically modified Bt crops have allowed great benefits to farmers but show activity limited to lepidopteran pests. This work reports on procedures adopted for integration and expression of a cry transgene conferring resistance to boll weevil and fall armyworm by using molecular tools. Four Brazilian cotton cultivars were microinjected with a minimal linear cassette generating 1248 putative lines. Complete gene integration was found in only one line (T0-34) containing one copy of cry1Ia detected by Southern blot. Protein was expressed in high concentration at 45 days after emergence (dae), decreasing by approximately 50% at 90 dae. Toxicity of the cry protein was demonstrated in feeding bioassays revealing 56.7% mortality to boll weevil fed buds and 88.1% mortality to fall armyworm fed leaves. A binding of cry1Ia antibody was found in the midgut of boll weevils fed on T0-34 buds in an immunodetection assay. The gene introduced into plants confers resistance to boll weevil and fall armyworm. Transmission of the transgene occurred normally to T1 progeny. All plants showed phenotypically normal growth, with fertile flowers and abundant seeds. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  4. Rational Practices to Manage Boll Weevils Colonization and Population Growth on Family Farms in the Semiárido Region of Brazil.

    Science.gov (United States)

    Neves, Robério C S; Colares, Felipe; Torres, Jorge B; Santos, Roberta L; Bastos, Cristina S

    2014-10-31

    Because boll weevil, Anthonomus grandis Boh. develops partially protected inside cotton fruiting structures, once they become established in a field, they are difficult to control, even with nearly continuous insecticide spray. During two cotton-growing seasons in the Semiárido region of Pernambuco State, Brazil, we tested the use of kaolin sprays to disrupt plant colonization through visual cue interference, combined with removal of fallen fruiting bodies to restrain boll weevil population growth after colonization. Kaolin spray under non-choice trials resulted in 2.2×, 4.4×, and 8.6× fewer weevils, oviposition and feeding punctures on kaolin-treated plants, respectively, despite demonstrating no statistical differences for colonization and population growth. Early season sprays in 2010 occurred during a period of rainfall, and hence, under our fixed spraying schedule no significant differences in boll weevil colonization were detected. In 2011, when kaolin sprays were not washed out by rain, delayed boll weevil colonization and reduction on attacked fruiting bodies were observed in eight out of 12 evaluations, and kaolin-treated plots had 2.7× fewer damaged fruiting bodies compared to untreated plots. Adoption of simple measures such as removal of fallen fruiting bodies and prompt reapplication of kaolin sprays after rainfall show promise in reducing boll weevil infestation.

  5. Rational Practices to Manage Boll Weevils Colonization and Population Growth on Family Farms in the Semiárido Region of Brazil

    Directory of Open Access Journals (Sweden)

    Robério C. S. Neves

    2014-10-01

    Full Text Available Because boll weevil, Anthonomus grandis Boh. develops partially protected inside cotton fruiting structures, once they become established in a field, they are difficult to control, even with nearly continuous insecticide spray. During two cotton-growing seasons in the Semiárido region of Pernambuco State, Brazil, we tested the use of kaolin sprays to disrupt plant colonization through visual cue interference, combined with removal of fallen fruiting bodies to restrain boll weevil population growth after colonization. Kaolin spray under non-choice trials resulted in 2.2×, 4.4×, and 8.6× fewer weevils, oviposition and feeding punctures on kaolin-treated plants, respectively, despite demonstrating no statistical differences for colonization and population growth. Early season sprays in 2010 occurred during a period of rainfall, and hence, under our fixed spraying schedule no significant differences in boll weevil colonization were detected. In 2011, when kaolin sprays were not washed out by rain, delayed boll weevil colonization and reduction on attacked fruiting bodies were observed in eight out of 12 evaluations, and kaolin-treated plots had 2.7× fewer damaged fruiting bodies compared to untreated plots. Adoption of simple measures such as removal of fallen fruiting bodies and prompt reapplication of kaolin sprays after rainfall show promise in reducing boll weevil infestation.

  6. Isolation and characterization of farnesyl diphosphate synthase from the cotton boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Taban, A Huma; Tittiger, Claus; Blomquist, Gary J; Welch, William H

    2009-06-01

    Farnesyl diphosphate synthase (FPPS) catalyzes the consecutive condensation of two molecules of isopentenyl diphosphate with dimethylallyl diphosphate to form farnesyl diphosphate (FPP). In insects, FPP is used for the synthesis of ubiquinones, dolicols, protein prenyl groups, and juvenile hormone. A full-length cDNA of FPPS was cloned from the cotton boll weevil, Anthonomus grandis (AgFPPS). AgFPPS cDNA consists of 1,835 nucleotides and encodes a protein of 438 amino acids. The deduced amino acid sequence has high similarity to previously isolated insect FPPSs and other known FPPSs. Recombinant AgFPPS expressed in E. coli converted labeled isopentenyl diphosphate in the presence of dimethylallyl diphosphate to FPP. Southern blot analysis indicated the presence of a single copy gene. Using molecular modeling, the three-dimensional structure of coleopteran FPPS was determined and compared to the X-ray crystal structure of avian FPPS. The alpha-helical fold is conserved in AgFPPS and the size of the active site cavity is consistent with the enzyme being a FPPS. (c) 2009 Wiley Periodicals, Inc.

  7. Resistance to inhibitors of cholinesterase (Ric-8A and Gαi contribute to cytokinesis abscission by controlling vacuolar protein-sorting (Vps34 activity.

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    Cedric Boularan

    Full Text Available Resistance to inhibitors of cholinesterase (Ric-8A is a guanine nucleotide exchange factor for Gαi, Gαq, and Gα12/13, which is implicated in cell signaling and as a molecular chaperone required for the initial association of nascent Gα subunits with cellular membranes. Ric-8A, Gαi subunits, and their regulators are localized at the midbody prior to abscission and linked to the final stages of cell division. Here, we identify a molecular mechanism by which Ric-8A affects cytokinesis and abscission by controlling Vps34 activity. We showed that Ric-8A protein expression is post-transcriptionally controlled during the cell cycle reaching its maximum levels at mitosis. A FRET biosensor created to measure conformational changes in Ric-8A by FLIM (Fluorescence Lifetime Imaging Microscopy revealed that Ric-8A was in a close-state during mitosis and particularly so at cytokinesis. Lowering Ric-8A expression delayed the abscission time of dividing cells, which correlated with increased intercellular bridge length and multinucleation. During cytokinesis, Ric-8A co-localized with Vps34 at the midbody along with Gαi and LGN, where these proteins functioned to regulate Vps34 phosphatidylinositol 3-kinase activity.

  8. Feeding and oviposition deterrent activities of flower buds of globemallow,Sphaeralcea emoryi torrey, against boll weevil,Anthonomus grandis Boheman (Coleoptera: Curculionidae).

    Science.gov (United States)

    Honda, H; Bowers, W S

    1996-01-01

    The globemallow,Sphaeralcea emoryi Torrey, a plant native to Arizona was evaluated as a source of feeding or oviposition deterrents to the boll weevil,Anthonomus grandis Boheman. Feeding and oviposition responses of reproductive weevils to the flower buds and artificial diets spiked with dry powder or extracts of the globemallow buds were determined. Boll weevils were deterred from feeding and ovipositing in the flower buds unless the calyxes were removed. Male and virgin female weevils were discouraged from feeding as much as gravid weevils. Secondary chemicals in the flower buds served primarily as feeding deterrents but also prevented oviposition. The concentration of these chemicals was highest in the calyxes of the buds, and potent deterrent activity could be extracted from the calyxes with methanol. Boll weevils were able to perceive the deterrents by contact chemosensory organs on the antennae, maxillary palps and labial palps.

  9. Transcriptomic events involved in melon mature-fruit abscission comprise the sequential induction of cell-wall degrading genes coupled to a stimulation of endo and exocytosis.

    Directory of Open Access Journals (Sweden)

    Jorge Corbacho

    Full Text Available Mature-fruit abscission (MFA in fleshy-fruit is a genetically controlled process with mechanisms that, contrary to immature-fruit abscission, has not been fully characterized. Here, we use pyrosequencing to characterize the transcriptomes of melon abscission zone (AZ at three stages during AZ-cell separation in order to understand MFA control at an early stage of AZ-activation.The results show that by early induction of MFA, the melon AZ exhibits major gene induction, while by late induction of MFA, melon AZ shows major gene repression. Although some genes displayed similar regulation in both early and late induction of abscission, such as EXT1-EXT4, EGase1, IAA2, ERF1, AP2D15, FLC, MADS2, ERAF17, SAP5 and SCL13 genes, the majority had different expression patterns. This implies that time-specific events occur during MFA, and emphasizes the value of characterizing multiple time-specific abscission transcriptomes. Analysis of gene-expression from these AZs reveal that a sequential induction of cell-wall-degrading genes is associated with the upregulation of genes involved in endo and exocytosis, and a shift in plant-hormone metabolism and signaling genes during MFA. This is accompanied by transcriptional activity of small-GTPases and synthaxins together with tubulins, dynamins, V-type ATPases and kinesin-like proteins potentially involved in MFA signaling. Early events are potentially controlled by down-regulation of MADS-box, AP2/ERF and Aux/IAA transcription-factors, and up-regulation of homeobox, zinc finger, bZIP, and WRKY transcription-factors, while late events may be controlled by up-regulation of MYB transcription-factors.Overall, the data provide a comprehensive view on MFA in fleshy-fruit, identifying candidate genes and pathways associated with early induction of MFA. Our comprehensive gene-expression profile will be very useful for elucidating gene regulatory networks of the MFA in fleshy-fruit.

  10. Fibre qualities of bolls developed under different day and night temperatures in various Pakistani cotton varieties and mutant strains

    International Nuclear Information System (INIS)

    Bandesha, A.A.; Aslam, M.; Ishaque, W.; Haq, M.A.

    2004-01-01

    Four commercial cotton varieties NIAB-78, B-557, SLH-41, MNH-93 and four advanced mutants strains N-82, L-21, L-25 and M-626 were used to study the effect of temperature on fibre quality during boll developing stage. The results showed that varieties differed significantly in all fibre quality parameters. There was significant increase in fibre length under medium temperature range while significant increase in fibre strength and highly significant increase in Micronaire values and maturity index under high temperature conditions. The medium temperature range (24.5 to 30.6 C) seemed to be ideal for cotton fibre development. (author)

  11. Eradication of the cotton boll weevil (Anthonomus grandis) in the United States - A successful multi-regional approach

    International Nuclear Information System (INIS)

    Cunningham, Gary L.; Grefenstette, William J.

    2000-01-01

    The cotton boll weevil, Anthonomus grandis Boheman, is believed to have entered the US from Mexico and was first detected in South Texas in 1892. Since that time, the pest has spread throughout most of the nation's cotton-producing areas and has become the industry's number one nemesis. More than US$13 billion in economic losses have occurred since its introduction, with recent annual expenditures of more than US$300 million for control costs alone. Although the weevil has been eradicated from over 4 million acres, its presence in non-programme areas continues to dictate production practices within the mid-south, Texas and Oklahoma

  12. Transcriptome analysis in cotton boll weevil (Anthonomus grandis and RNA interference in insect pests.

    Directory of Open Access Journals (Sweden)

    Alexandre Augusto Pereira Firmino

    Full Text Available Cotton plants are subjected to the attack of several insect pests. In Brazil, the cotton boll weevil, Anthonomus grandis, is the most important cotton pest. The use of insecticidal proteins and gene silencing by interference RNA (RNAi as techniques for insect control are promising strategies, which has been applied in the last few years. For this insect, there are not much available molecular information on databases. Using 454-pyrosequencing methodology, the transcriptome of all developmental stages of the insect pest, A. grandis, was analyzed. The A. grandis transcriptome analysis resulted in more than 500.000 reads and a data set of high quality 20,841 contigs. After sequence assembly and annotation, around 10,600 contigs had at least one BLAST hit against NCBI non-redundant protein database and 65.7% was similar to Tribolium castaneum sequences. A comparison of A. grandis, Drosophila melanogaster and Bombyx mori protein families' data showed higher similarity to dipteran than to lepidopteran sequences. Several contigs of genes encoding proteins involved in RNAi mechanism were found. PAZ Domains sequences extracted from the transcriptome showed high similarity and conservation for the most important functional and structural motifs when compared to PAZ Domains from 5 species. Two SID-like contigs were phylogenetically analyzed and grouped with T. castaneum SID-like proteins. No RdRP gene was found. A contig matching chitin synthase 1 was mined from the transcriptome. dsRNA microinjection of a chitin synthase gene to A. grandis female adults resulted in normal oviposition of unviable eggs and malformed alive larvae that were unable to develop in artificial diet. This is the first study that characterizes the transcriptome of the coleopteran, A. grandis. A new and representative transcriptome database for this insect pest is now available. All data support the state of the art of RNAi mechanism in insects.

  13. Comparisons of boll weevil (Coleoptera: Curculionidae) pheromone traps with and without kill strips.

    Science.gov (United States)

    Suh, C P C; Armstrong, J S; Spurgeon, D W; Duke, S

    2009-02-01

    Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), eradication programs typically equip pheromone traps with an insecticide-impregnated kill strip. These strips are intended to kill captured insects, thereby simplifying trap servicing and reducing the loss of weevils from predation and escape. However, the effectiveness of kill strips has not been extensively evaluated. We examined the influences of kill strips on weevil captures, trap servicing, and the incidences of weevil predation and trap obstruction (e.g., by spider webs). Evaluations were conducted weekly during three different production periods (pre- to early-, late-, and postseason) of cotton, Gossypium hirsutum L., to represent different environmental conditions and weevil population levels. Within each period, mean weekly captures of weevils in traps with and without kill strips were statistically similar. On average, traps with kill strips took 9 s longer to service than traps without kill strips, but statistical differences were only detected during the late-season period. Overall, the mean weekly proportion of traps with evidence of weevil predation or trap obstruction was significantly lower for traps with kill strips (0.25) than for traps without kill strips (0.37). However, this reduction in the frequency of weevil predation or trap obstruction was too small to produce a corresponding increase in the numbers of weevils captured. In light of these findings, the use of kill strips is likely unnecessary in eradication programs, but may be a consideration in situations when the numbers of deployed traps are reduced and chronic problems with weevil predation or trap obstruction exist.

  14. Transcriptome analysis in cotton boll weevil (Anthonomus grandis) and RNA interference in insect pests.

    Science.gov (United States)

    Firmino, Alexandre Augusto Pereira; Fonseca, Fernando Campos de Assis; de Macedo, Leonardo Lima Pepino; Coelho, Roberta Ramos; Antonino de Souza, José Dijair; Togawa, Roberto Coiti; Silva-Junior, Orzenil Bonfim; Pappas, Georgios Joannis; da Silva, Maria Cristina Mattar; Engler, Gilbert; Grossi-de-Sa, Maria Fatima

    2013-01-01

    Cotton plants are subjected to the attack of several insect pests. In Brazil, the cotton boll weevil, Anthonomus grandis, is the most important cotton pest. The use of insecticidal proteins and gene silencing by interference RNA (RNAi) as techniques for insect control are promising strategies, which has been applied in the last few years. For this insect, there are not much available molecular information on databases. Using 454-pyrosequencing methodology, the transcriptome of all developmental stages of the insect pest, A. grandis, was analyzed. The A. grandis transcriptome analysis resulted in more than 500.000 reads and a data set of high quality 20,841 contigs. After sequence assembly and annotation, around 10,600 contigs had at least one BLAST hit against NCBI non-redundant protein database and 65.7% was similar to Tribolium castaneum sequences. A comparison of A. grandis, Drosophila melanogaster and Bombyx mori protein families' data showed higher similarity to dipteran than to lepidopteran sequences. Several contigs of genes encoding proteins involved in RNAi mechanism were found. PAZ Domains sequences extracted from the transcriptome showed high similarity and conservation for the most important functional and structural motifs when compared to PAZ Domains from 5 species. Two SID-like contigs were phylogenetically analyzed and grouped with T. castaneum SID-like proteins. No RdRP gene was found. A contig matching chitin synthase 1 was mined from the transcriptome. dsRNA microinjection of a chitin synthase gene to A. grandis female adults resulted in normal oviposition of unviable eggs and malformed alive larvae that were unable to develop in artificial diet. This is the first study that characterizes the transcriptome of the coleopteran, A. grandis. A new and representative transcriptome database for this insect pest is now available. All data support the state of the art of RNAi mechanism in insects.

  15. Receptor chirality and behavioral specificity of the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae), for its pheromone, (+)-grandisol.

    Science.gov (United States)

    Dickens, J C; Mori, K

    1989-02-01

    Electrophysiological recordings from antennal olfactory receptors and field behavioral experiments showed both male and female boll weevils,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to respond specifically to (+)-grandisol, an enantiomer of compound I of the boll weevil aggregation pheromone. Single-cell recordings revealed antennal olfactory neurons in both male and female weevils keyed to (+)-grandisol. Electroantennograms in response to serial dilutions of the grandisol enaniiomers showed a threshold 100 to 1000 times lower for (+)-grandisol relative to its antipode. In field behavioral experiments, both sexes were significantly more attracted to (+)-grandisol in combination with the three other pheromone components than the combination with (-)-grandisol. When (-)-grandisol was placed with the (+)-enantiomer at equal dosages, a slight although statistically insignificant inhibition occurred. Subsequent field tests showed that the low level of attraction exhibited by (-)-grandisol in combination with the other three pheromone components could be attributed to the other three components alone. These results are in contrast with an earlier study, which found (-)-grandisol to be as attractive as the (+)-enantiomer.

  16. Employing in vitro directed molecular evolution for the selection of α-amylase variant inhibitors with activity toward cotton boll weevil enzyme.

    Science.gov (United States)

    da Silva, Maria Cristina Mattar; Del Sarto, Rafael Perseghini; Lucena, Wagner Alexandre; Rigden, Daniel John; Teixeira, Fabíola Rodrigues; Bezerra, Caroline de Andrade; Albuquerque, Erika Valéria Saliba; Grossi-de-Sa, Maria Fatima

    2013-09-20

    Numerous species of insect pests attack cotton plants, out of which the cotton boll weevil (Anthonomus grandis) is the main insect in Brazil and must be controlled to avert large economic losses. Like other insect pests, A. grandis secretes a high level of α-amylases in the midgut lumen, which are required for digestion of carbohydrates. Thus, α-amylase inhibitors (α-AIs) represent a powerful tool to apply in the control of insect pests. Here, we applied DNA shuffling and phage display techniques and obtained a combinatorial library containing 10⁸ α-AI variant forms. From this library, variants were selected exhibiting in vitro affinity for cotton boll weevil α-amylases. Twenty-six variant sequences were cloned into plant expression vectors and expressed in Arabidopsis thaliana. Transformed plant extracts were assayed in vitro to select specific and potent α-amylase inhibitors against boll weevil amylases. While the wild type inhibitors, used to create the shuffled library, did not inhibit the A. grandis α-amylases, three α-AI mutants, named α-AIC3, α-AIA11 and α-AIG4 revealed high inhibitory activities against A. grandis α-amylases in an in vitro assay. In summary, data reported here shown the potential biotechnology of new α-AI variant genes for cotton boll weevil control. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Genetic profiling to determine potential origins of boll weevils (Coleoptera: Curculionidae) captured in a Texas eradication zone: endemicity, immigration, or sabotage?

    Science.gov (United States)

    Kim, Kyung Seok; Sappington, Thomas W; Allen, Charles T

    2008-12-01

    Thirty-seven boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), were captured in pheromone traps near Lubbock, TX, in the Southern High Plains/Caprock eradication zone during August-October 2006. No boll weevils had been captured in this zone or neighboring zones to the north earlier in the year, and only very low numbers had been captured in neighboring zones to the south and east. Therefore, the captures near Lubbock were unexpected. Five of the weevils captured the last week of August were preserved and genotyped at 10 microsatellite loci for comparison with a database of genotypes for 22 boll weevil populations sampled from eight U.S. states and four locations in Mexico. The Lubbock population itself is an unlikely source, suggesting that the captured weevils probably did not originate from a low-level endemic population. Populations from eastern states, Mexico, and Big Spring, TX, can be confidently excluded as potential source regions. Although the Weslaco and Kingsville, TX, areas cannot be statistically excluded, they are unlikely sources. The most likely sources are nearby areas in New Mexico, TX, or southwest Oklahoma, or from areas of eastern Texas represented by Waxahachie and El Campo populations. Together, genetic and circumstantial evidence suggest either that the trapped boll weevils are the offspring of alone mated female that immigrated from eastern Texas earlier in the summer or that weevils originally captured near Waxahachie but now long-dead were planted in the traps by a disgruntled employee of the eradication program.

  18. Conservation of the abscission signaling peptide IDA during Angiosperm evolution: withstanding genome duplications and gain and loss of the receptors HAE/HSL2

    Directory of Open Access Journals (Sweden)

    Ida M. Stø

    2015-10-01

    Full Text Available The peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA, which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE and HAESA-LIKE2 (HSL2, controls different cell separation events in Arabidopsis thaliana. We hypothesize the involvement of this signaling module in abscission processes in other plant species even though they may shed other organs than A. thaliana. As the first step towards testing this hypothesis from an evolutionarily perspective we have identified genes encoding putative orthologues of IDA and its receptors by BLAST searches of publically available protein, nucleotide and genome databases for angiosperms. Genes encoding IDA or IDA-LIKE (IDL peptides and HSL proteins were found in all investigated species, which were selected as to represent each angiosperm order with available genomic sequences. The 12 amino acids representing the bioactive peptide in A. thaliana have virtually been unchanged throughout the evolution of the angiosperms; however, the number of IDL and HSL genes varies between different orders and species. The phylogenetic analyses suggest that IDA, HSL2 and the related HSL1 gene, were present in the species that gave rise to the angiosperms. HAE has arisen from HSL1 after a genome duplication that took place after the monocot - eudicots split. HSL1 has also independently been duplicated in the monocots, while HSL2 has been lost in gingers (Zingiberales and grasses (Poales. IDA has been duplicated in eudicots to give rise to functionally divergent IDL peptides. We postulate that the high number of IDL homologs present in the core eudicots is a result of multiple whole genome duplications. We substantiate the involvement of IDA and HAE/HSL2 homologs in abscission by providing gene expression data of different organ separation events from various species.

  19. A jasmonate ZIM-domain protein NaJAZd regulates floral jasmonic acid levels and counteracts flower abscission in Nicotiana attenuata plants.

    Directory of Open Access Journals (Sweden)

    Youngjoo Oh

    Full Text Available Jasmonic acid is an important regulator of plant growth, development and defense. The jasmonate-ZIM domain (JAZ proteins are key regulators in jasmonate signaling ubiquitously present in flowering plants but their functional annotation remains largely incomplete. Recently, we identified 12 putative JAZ proteins in native tobacco, Nicotiana attenuata, and initiated systematic functional characterization of these proteins by reverse genetic approaches. In this report, Nicotiana attenuata plants silenced in the expression of NaJAZd (irJAZd by RNA interference were used to characterize NaJAZd function. Although NaJAZd transcripts were strongly and transiently up-regulated in the rosette leaves by simulated herbivory treatment, we did not observe strong defense-related phenotypes, such as altered herbivore performance or the constitutive accumulation of defense-related secondary metabolites in irJAZd plants compared to wild type plants, both in the glasshouse and the native habitat of Nicotiana attenuata in the Great Basin Desert, Utah, USA. Interestingly, irJAZd plants produced fewer seed capsules than did wild type plants as a result of increased flower abscission in later stages of flower development. The early- and mid-developmental stages of irJAZd flowers had reduced levels of jasmonic acid and jasmonoyl-L-isoleucine, while fully open flowers had normal levels, but these were impaired in NaMYB305 transcript accumulations. Previously, NaMYB305-silenced plants were shown to have strong flower abscission phenotypes and contained lower NECTARIN 1 transcript levels, phenotypes which are copied in irJAZd plants. We propose that the NaJAZd protein is required to counteract flower abscission, possibly by regulating jasmonic acid and jasmonoyl-L-isoleucine levels and/or expression of NaMYB305 gene in Nicotiana attenuata flowers. This novel insight into the function of JAZ proteins in flower and seed development highlights the diversity of functions

  20. Susceptibility of Anthonomus grandis (cotton boll weevil) and Spodoptera frugiperda (fall armyworm) to a cry1ia-type toxin from a Brazilian Bacillus thuringiensis strain.

    Science.gov (United States)

    Grossi-de-Sa, Maria Fatima; Quezado de Magalhaes, Mariana; Silva, Marilia Santos; Silva, Shirley Margareth Buffon; Dias, Simoni Campos; Nakasu, Erich Yukio Tempel; Brunetta, Patricia Sanglard Felipe; Oliveira, Gustavo Ramos; Neto, Osmundo Brilhante de Oliveira; Sampaio de Oliveira, Raquel; Soares, Luis Henrique Barros; Ayub, Marco Antonio Zachia; Siqueira, Herbert Alvaro Abreu; Figueira, Edson L Z

    2007-09-30

    Different isolates of the soil bacterium Bacillus thuringiensis produce multiple crystal (Cry) proteins toxic to a variety of insects, nematodes and protozoans. These insecticidal Cry toxins are known to be active against specific insect orders, being harmless to mammals, birds, amphibians, and reptiles. Due to these characteristics, genes encoding several Cry toxins have been engineered in order to be expressed by a variety of crop plants to control insectpests. The cotton boll weevil, Anthonomus grandis, and the fall armyworm, Spodoptera frugiperda, are the major economically devastating pests of cotton crop in Brazil, causing severe losses, mainly due to their endophytic habit, which results in damages to the cotton boll and floral bud structures. A cry1Ia-type gene, designated cry1Ia12, was isolated and cloned from the Bt S811 strain. Nucleotide sequencing of the cry1Ia12 gene revealed an open reading frame of 2160 bp, encoding a protein of 719 amino acid residues in length, with a predicted molecular mass of 81 kDa. The amino acid sequence of Cry1Ia12 is 99% identical to the known Cry1Ia proteins and differs from them only in one or two amino acid residues positioned along the three domains involved in the insecticidal activity of the toxin. The recombinant Cry1Ia12 protein, corresponding to the cry1Ia12 gene expressed in Escherichia coli cells, showed moderate toxicity towards first instar larvae of both cotton boll weevil and fall armyworm. The highest concentration of the recombinant Cry1Ia12 tested to achieve the maximum toxicities against cotton boll weevil larvae and fall armyworm larvae were 230 microg/mL and 5 microg/mL, respectively. The herein demonstrated insecticidal activity of the recombinant Cry1Ia12 toxin against cotton boll weevil and fall armyworm larvae opens promising perspectives for the genetic engineering of cotton crop resistant to both these devastating pests in Brazil.

  1. Aspectos biológicos de adultos de um parasitóide do bicudo do algodoeiro Biological aspects of a parasitoid of the cotton boll weevil

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Avelino Araújo

    1999-10-01

    Full Text Available Bracon sp. é um importante agente de controle biológico de Anthonomus grandis (Boheman. Estudaram-se em laboratório, aspectos biológicos de Bracon sp., utilizando-se como hospedeiro larva do bicudo do algodoeiro, a temperatura de 26 ± 2oC, 70 ± 5% UR e fotofase de 12 horas. O ciclo biológico de Bracon sp. teve duração média de 11,7 dias, o período de incubação de 1 dia, o período médio larval de 3,9 dias, com 4 estádios; a viabilidade larval de 98,7%, o período pré-pupal de 0,6 dia, o período pupal de 6,2 dias, o tempo de pré-oviposição de 4,0 dias. A fêmea colocou, em média, 74 ovos em um período de 27,2 dias, a oviposição média diária de 2,7 ovos/fêmea/dia, o período de pós-oviposição de 3,7 dias e a longevidade de Bracon sp. foi de 34 dias para as fêmeas. A informação da biologia deste braconídeo é necessária para desenvolver estratégias de propagação e colonização do parasitóide.Bracon sp. is an important biological control agent of Anthonomus grandis, the cotton Boll weevil. The objective of this work was to evaluate biological aspects of Bracon sp. using cotton Boll weevil larvae as host, at conditions of 26 ± 2oC, with 70 ± 5% RH and 12h photoperiod. The complete life cycle of Bracon sp. was 11.7 days. The incubation period lasted 1.0 day and the larval period 3.9 days with four stages; the viability of the larvae was 98.7%; prepupal period lasted 0.6 day; and the pupal period lasted 6.2 days. Preoviposition period was 4.0 days, and the females laid an average of 74.0 eggs with in an oviposition period of 27.2 days, while the average daily oviposition rate was 2.7 eggs per female per day, posovipositional lasted 3.7 days, and the longevity of Bracon sp. was 34.0 days in females. The information of the biology of this Braconid is needed to develop parasitoid propagation and colonization strategies.

  2. Activity of a Brazilian strain of Bacillus thuringiensis israelensis against the cotton Boll Weevil Anthonomus grandis Boheman (Coleoptera: Tenebrionidae).

    Science.gov (United States)

    Monnerat, R; Martins, E; Praça, L; Dumas, V; Berry, C

    2012-02-01

    A Brazilian Bacillus thuringiensis subspecies israelensis, toxic to Diptera, including mosquitoes, was found also to show toxicity to the coleopteran boll weevil Anthonomus grandis Boheman at an equivalent level to that of the standard coleopteran-active B. thuringiensis subspecies tenebrionis T08017. Recombinant B. thuringiensis strains expressing the individual Cyt1Aa, Cry4Aa, Cry4Ba and Cry11Aa toxins from this strain were assessed to evaluate their potential contribution to the activity against A. grandis, either alone or in combination. Whilst individual toxins produced mortality, none was sufficiently potent to allow calculation of LC50 values. Combinations of toxins were unable to attain the same potency as the parental B. thuringiensis subsp. israelensis, suggesting a major role for other factors produced by this strain.

  3. Orientation of boll weevil,Anthonomus grandis boh. (Coleoptera: Curculionidae), to pheromone and volatile host compound in the laboratory.

    Science.gov (United States)

    Dickens, J C

    1986-01-01

    Behavioral responses of male and female boll weevils to the aggregation pheromone, grandlure, and the major volatile of cotton, β-bisabolol, were investigated using a new dual-choice olfactometer. Dosage-response experiments revealed both males and females to be attracted by the aggregation pheromone at the 1.0 μg dosage. However, only males were attracted to β-bisabolol (1.0 μg). Both sexes were repelled by the highest dosage ofβ-bisabolol tested (10 μg). In preference experiment, males chose grandlure over β-bisabolol, while both sexes chose the combination of grandlure + β-bisabolol over β-bisabolol alone. There was some evidence for synergism between pheromone and plant odor for the females. The results correlate well with previous electrophysiological and behavioral experiments.

  4. Endogenous Ethylene Concentration Is Not a Major Determinant of Fruit Abscission in Heat-Stressed Cotton (Gossypium hirsutum L.

    Directory of Open Access Journals (Sweden)

    Ullah Najeeb

    2017-09-01

    Full Text Available We investigated the role of ethylene in the response of cotton to high temperature using cotton genotypes with genetically interrupted ethylene metabolism. In the first experiment, Sicot 71BRF and 5B (a lintless variant with compromised ethylene metabolism were exposed to 45°C, either by instantaneous heat shock or by ramping temperatures by 3°C daily for 1 week. One day prior to the start of heat treatment, half the plants were sprayed with 0.8 mM of the ethylene synthesis inhibitor, aminoethoxyvinylglycine (AVG. In a subsequent experiment, Sicot 71BRF and a putatively heat-tolerant line, CIM 448, were exposed to 36 or 45°C for 1 week, and half the plants were sprayed with 20 μM of the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid, (ACC. High temperature exposure of plants in both experiments was performed at the peak reproductive phase (65–68 days after sowing. Elevated temperature (heat shock or ramping to 45°C significantly reduced production and retention of fruits in all cotton lines used in this study. At the termination of heat treatment, cotton plants exposed to 45°C had at least 50% fewer fruits than plants under optimum temperature in all three genotypes, while plants at 36°C remained unaffected. Heat-stressed plants continued producing new squares (fruiting buds after termination of heat stress but these squares did not turn into cotton bolls due to pollen infertility. In vitro inhibition of pollen germination by high temperatures supported this observation. Leaf photosynthesis (Pn of heat-stressed plants (45°C measured at the end of heat treatments remained significantly inhibited, despite an increased leaf stomatal conductance (gs, suggesting that high temperature impairs Pn independently of stomatal behavior. Metabolic injury was supported by high relative cellular injury and low photosystem II yield of the heat-stressed plants, indicating that high temperature impaired photosynthetic electron transport. Both

  5. Transcriptomics of shading-induced and NAA-induced abscission in apple (Malus domestica) reveals a shared pathway involving reduced photosynthesis, alterations in carbohydrate transport and signaling and hormone crosstalk.

    Science.gov (United States)

    Zhu, Hong; Dardick, Chris D; Beers, Eric P; Callanhan, Ann M; Xia, Rui; Yuan, Rongcai

    2011-10-17

    Naphthaleneacetic acid (NAA), a synthetic auxin analogue, is widely used as an effective thinner in apple orchards. When applied shortly after fruit set, some fruit abscise leading to improved fruit size and quality. However, the thinning results of NAA are inconsistent and difficult to predict, sometimes leading to excess fruit drop or insufficient thinning which are costly to growers. This unpredictability reflects our incomplete understanding of the mode of action of NAA in promoting fruit abscission. Here we compared NAA-induced fruit drop with that caused by shading via gene expression profiling performed on the fruit abscission zone (FAZ), sampled 1, 3, and 5 d after treatment. More than 700 genes with significant changes in transcript abundance were identified from NAA-treated FAZ. Combining results from both treatments, we found that genes associated with photosynthesis, cell cycle and membrane/cellular trafficking were downregulated. On the other hand, there was up-regulation of genes related to ABA, ethylene biosynthesis and signaling, cell wall degradation and programmed cell death. While the differentially expressed gene sets for NAA and shading treatments shared only 25% identity, NAA and shading showed substantial similarity with respect to the classes of genes identified. Specifically, photosynthesis, carbon utilization, ABA and ethylene pathways were affected in both NAA- and shading-induced young fruit abscission. Moreover, we found that NAA, similar to shading, directly interfered with leaf photosynthesis by repressing photosystem II (PSII) efficiency within 10 minutes of treatment, suggesting that NAA and shading induced some of the same early responses due to reduced photosynthesis, which concurred with changes in hormone signaling pathways and triggered fruit abscission. This study provides an extensive transcriptome study and a good platform for further investigation of possible regulatory genes involved in the induction of young fruit

  6. Alternative food sources and over wintering feeding behavior of the boll weevil, Anthonomus grandis boheman (coleoptera: curculionidae) under the tropical conditions of central Brazil

    International Nuclear Information System (INIS)

    Ribeiro, Paulina de A.; Sujii, Edison R.; Pires, Carmen S.S.; Fontes, Eliana M.G.; Diniz, Ivone R.; Salgado-Labouriau, Maria L.

    2010-01-01

    The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae (50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions. (author)

  7. Alternative food sources and over wintering feeding behavior of the boll weevil, Anthonomus grandis boheman (coleoptera: curculionidae) under the tropical conditions of central Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Paulina de A.; Sujii, Edison R.; Pires, Carmen S.S.; Fontes, Eliana M.G. [EMBRAPA Recursos Geneticos e Biotecnologia (CENARGEN), Brasilia, DF (Brazil)], e-mail: paulina723@hotmail.com, e-mail: sujii@cenargen.embrapa.br, e-mail: cpires@cenargen.embrapa.br, e-mail: eliana@cenargen.embrapa.br; Diniz, Ivone R. [Universidade de Brasilia (UnB), DF (Brazil). Dept. de Zoologia], e-mail: irdiniz@unb.br; Medeiros, Maria A. de; Branco, Marina C. [EMBRAPA Hortalicas, Brasilia, DF (Brazil)], e-mail: medeiros@cnph.embrapa.br, e-mail: marina@cnph.embrapa.br; Salgado-Labouriau, Maria L. [Universidade de Brasilia (UnB), DF (Brazil). Dept. de Geologia], e-mail: mlea@unb.br

    2010-01-15

    The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae (50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions. (author)

  8. Selection of Beauveria bassiana sensu lato and Metarhizium anisopliae sensu lato isolates as microbial control agents against the boll weevil (Anthonomus grandis) in Argentina.

    Science.gov (United States)

    Nussenbaum, A L; Lecuona, R E

    2012-05-01

    The boll weevil (Anthonomus grandis) is the main pest of cotton in the Americas. The aim of this work was to evaluate isolates of the entomopathogenic fungi Beauveria bassiana sensu lato and Metarhizium anisopliae sensu lato virulent against A. grandis. Screening was performed to evaluate the pathogenicity of 28 isolates of M. anisopliae s.l. and 66 isolates of B. bassiana s.l. against boll weevil adults. To select the isolates, LC(50) values of the most virulent isolates were calculated, and compatibility between the fungi and insecticides was studied. In addition, the effects of these isolates on the feeding behavior of the adults were evaluated. Isolates Ma 50 and Ma 20 were the most virulent against A. grandis and their LC(50) values were 1.13×10(7) and 1.20×10(7) conidia/ml, respectively. In addition, these isolates were compatible with pyrethroid insecticides, but none with endosulfan. On the other hand, infected females reduced the damage caused by feeding on the cotton squares and their weight gain. This shows that entomopathogenic fungi cause mortality in the insects, but also these fungi could influence the feeding behavior of the females. In summary, these results indicate the possibility of the use of M. anisopliae s.l. as a microbiological control agent against boll weevils. Also, this species could be included in an Integrated Pest Management program. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Alternative food sources and overwintering feeding behavior of the boll weevil, Anthonomus grandis boheman (Coleoptera: Curculionidae) under the tropical conditions of Central Brazil.

    Science.gov (United States)

    Ribeiro, Paulina de A; Sujii, Edison R; Diniz, Ivone R; Medeiros, Maria A de; Salgado-Labouriau, Maria L; Branco, Marina C; Pires, Carmen S S; Fontes, Eliana M G

    2010-01-01

    The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae(50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions.

  10. Comportamento de progênies oriundas de raças primitivas de algodão herbáceo frente ao ataque do bicudo Behavior of lines from cotton primitive race stocks to attack of the boll weevil

    Directory of Open Access Journals (Sweden)

    Francisco José Correia Farias

    1999-12-01

    Full Text Available Com o objetivo de obter linhagens resistentes ao bicudo-do-algodoeiro (Anthonomus grandis Boheman, a Embrapa-Centro Nacional de Pesquisa de Algodão vem testando progênies oriundas de raças primitivas de algodoeiro herbáceo (Gossypium hirsutum L. originárias do México e da América Central, que apresentam níveis aceitáveis de resistência ao bicudo. Em 1991 e 1992, as progênies em BC1F5 e BC1F6 oriundas das linhagens Texas 277, Texas 326 e Texas 1180, Texas 297, Texas 339, Texas 766 e Texas 1134, foram avaliadas com relação à resistência ao bicudo. O delineamento experimental utilizado foi o de blocos ao acaso, com seis repetições. A unidade experimental foi constituída por duas fileiras de 5 m, sob um espaçamento de 0,75 m x 0,20 m. As parcelas foram infestadas com adultos do bicudo recém-emergidos, a uma taxa de 10.000 adultos/ha. Aos seis dias após a liberação dos adultos, as parcelas foram pulverizadas com Cipermethrim, sendo realizadas em intervalos semanais. Foram procedidas cinco avaliações através da coleta de 33 botões florais ao acaso, por parcela. Os maiores níveis de resistência ao bicudo foram obtidos pelas progênies Texas 326-95-1, Texas 277-87-5, Texas 1180-99-2, Texas 297 e Texas 339, com redução de ataque de 44,0, 41,2, 32,0, 40,4 e 36,4%, respectivamente, em relação à testemunha CNPA 6H.The goal of the boll weevil (Anthonomus grandis Boheman resistance program of Embrapa-Centro Nacional de Pesquisa de Algodão is to obtain cultivars that give 80% suppression when compared to commercial cultivars. The primitive cottons (Gossypium hirsutum L. from Mexico and Central America have been known to show measurable levels of resistance to the boll weevil. In 1991 and 1992, the lines in BC1F5 and BC1F6 from Texas 277, Texas 326, Texas 1180, Texas 297, Texas 339, Texas 766 and Texas 1134 were evaluated to boll weevil resistance. The experiment was carried out at Campina Grande, PB, Brazil. The trial

  11. Differential effects of NAA and 2,4-D in reducing floret abscission in cestrum (Cestrum elegans) cut flowers are associated with their differential activation of Aux/IAA homologous genes.

    Science.gov (United States)

    Abebie, Bekele; Lers, Amnon; Philosoph-Hadas, Sonia; Goren, Raphael; Riov, Joseph; Meir, Shimon

    2008-01-01

    A previous study showed that the relative effectiveness of 2,4-dichlorophenoxyacetic acid (2,4-D) compared with that of 1-naphthaleneacetic acid (NAA) in reducing floret bud abscission in cestrum (Cestrum elegans) cut flowers was due to its acropetal transport. The aim of the present study was to examine if the differential effect of these auxins on floret abscission is reflected in the expression of Aux/IAA genes in the floret abscission zone (AZ). cDNAs were isolated by PCR-based cloning from the floret AZ of auxin-treated cut flowers. The expression patterns of the cDNAs in various tissues and the effect of indole-3-acetic acid (IAA), applied with or without cycloheximide, on their expression in the floret AZ were examined by northern blot analysis. The regulation of transcript accumulation in the floret AZ in response to NAA or 2,4-D was measured by real-time PCR during auxin pulsing of cut flowers and vase life, concomitantly with floret abscission. Six isolated cDNAs were identified to represent Aux/IAA homologous genes, designated as Cestrum elegans (Ce)-IAA1 to Ce-IAA6. Four Ce-IAA genes were characterized as early auxin-responsive genes (ARGs), and two (Ce-IAA1 and Ce-IAA5) as late ARGs. Only Ce-IAA5 was AZ-specific in floret buds. A temporal regulation of Ce-IAA transcript levels in the floret AZ was found, with 2,4-D inducing higher expression levels than NAA in floret buds. These Ce-IAA expression levels were negatively correlated with floret abscission. The differential transport characteristics of NAA and 2,4-D in cestrum cut flowers were reflected in differential activation of the Ce-IAA genes identified in the floret AZ. Therefore, Aux/IAA genes can be used as molecular markers to measure auxin activity, which reflects free auxin level in the AZ. Two of the identified genes, Ce-IAA1 and Ce-IAA5, may also have a regulatory role in abscission.

  12. Vitellogenin knockdown strongly affects cotton boll weevil egg viability but not the number of eggs laid by females.

    Science.gov (United States)

    Coelho, Roberta R; de Souza Júnior, José Dijair Antonino; Firmino, Alexandre A P; de Macedo, Leonardo L P; Fonseca, Fernando C A; Terra, Walter R; Engler, Gilbert; de Almeida Engler, Janice; da Silva, Maria Cristina M; Grossi-de-Sa, Maria Fatima

    2016-09-01

    Vitellogenin (Vg), a yolk protein precursor, is the primary egg nutrient source involved in insect reproduction and embryo development. The Cotton Boll weevil (CBW) Anthonomus grandis Boheman, the most important cotton pest in Americas, accumulates large amounts of Vg during reproduction. However, the precise role of this protein during embryo development in this insect remains unknown. Herein, we investigated the effects of vitellogenin (AgraVg) knockdown on the egg-laying and egg viability in A. grandis females, and also characterized morphologically the unviable eggs. AgraVg transcripts were found during all developmental stages of A. grandis, with highest abundance in females. Silencing of AgraVg culminated in a significant reduction in transcript amount, around 90%. Despite this transcriptional reduction, egg-laying was not affected in dsRNA-treated females but almost 100% of the eggs lost their viability. Eggs from dsRNA-treated females showed aberrant embryos phenotype suggesting interference at different stages of embryonic development. Unlike for other insects, the AgraVg knockdown did not affect the egg-laying ability of A. grandis, but hampered A. grandis reproduction by perturbing embryo development. We concluded that the Vg protein is essential for A. grandis reproduction and a good candidate to bio-engineer the resistance against this devastating cotton pest.

  13. Behavioral and neurosensory responses of the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to fluorinated analogs of aldehyde components of its pheromone.

    Science.gov (United States)

    Dickens, J C; Prestwich, G D; Sun, W C

    1991-06-01

    Competitive field tests with α-fluorinated analogs of compounds III and IV (III-α-F and IV-α-F, respectively) of the boll weevil,Anthonomus grandis Boh., aggregation pheromone showed these compounds, when combined with the other pheromone components [(±)-I and II], to be as attractive as grandlure [(+)-I, II, and III+IV]. Dose-response curves constructed from electroantennograms of male boll weevils to serial stimulus loads of III, IV, III-α-F, IV-α-F, and the corresponding acyl fluorinated analogs (III-acyl-F and IV-acyl-F) showed the α-fiuorinated analogs to be as active as the pheromone components (threshold=0.1 μg), while the acyl fluorinated analogs had a 10-100 x higher threshold (=1-10 μg). Single-neuron recordings showed that IV neurons and II neurons (Dickens, 1990) responded to IV-α-F and III-α-F, respectively, while IV-acyl-F and III-acyl-F were inactive. Since a previous study showed compounds I, II, and IV to be essential for behavioral responses in the field, it seems likely that the activity of the α-fluorinated analogs observed here is due to the stimulation of IV neurons by IV-α-F as indicated in single neuron recordings.

  14. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae) in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae) - doi: 10.4025/actascibiolsci.v33i4.8191

    OpenAIRE

    Aranda, Rodrigo; UFMS; Catian, Gisele; Universidade Federal de Mato Grosso do Sul; Bogiani, Paulo Alexandre; Universidade Federal de Mato Grosso do Sul; Inforzato, Igor; Universidade Federal de Mato Grosso do Sul

    2011-01-01

    This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbe...

  15. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae - doi: 10.4025/actascibiolsci.v33i4.8191 Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae - doi: 10.4025/actascibiolsci.v33i4.8191

    Directory of Open Access Journals (Sweden)

    Igor Inforzato

    2011-09-01

    Full Text Available This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and non-robber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear regression was used to see whether there was a relationship between the closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant. There were significant differences regarding all variables measured between soil and plant. A correlation was found at both closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant.This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and non-robber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear

  16. Site of pheromone biosynthesis and isolation of HMG-CoA reductase cDNA in the cotton boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Taban, A Huma; Fu, Jessica; Blake, Jacob; Awano, Ami; Tittiger, Claus; Blomquist, Gary J

    2006-08-01

    Isolated gut tissue from male cotton boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), incorporated radiolabeled acetate into components that co-eluted with monoterpenoid pheromone components on HPLC. This demonstrates that pheromone components of male A. grandis are produced de novo and strongly suggests that pheromone biosynthesis occurs in gut tissue. A central enzyme in isoprenoid biosynthesis is 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-R), and a full-length HMG-R cDNA was isolated from A. grandis. The predicted translation product was 54 and 45% identical to HMG-R from Ips paraconfusus and Drosophila melanogaster, respectively. HMG-R gene expression gradually increased with age in male A. grandis, which correlates with pheromone production. However, topical application of JH III did not significantly increase HMG-R mRNA levels.

  17. Esterases of laboratory-reared and field-collected cotton boll weevils, Anthonomus grandis Boh.: polymorphism of adult esterases and formal genetics of esterase II.

    Science.gov (United States)

    Biggers, C J; Bancroft, H R

    1977-04-01

    The esterases of the cotton boll weevil were separated by polyacrylamide gel electrophoresis into four major regions. These were named Est I-IV in order of migration from anode to origin. Polymorphism was observed in all regions. The Est II region was shown to consist of no more than two bands (fast and slow). The inheritance of the fast and slow bands of Est II was demonstrated to be controlled by codominant autosomal alleles. Analysis of the gene frequency of the Est II region showed that one field population was consistent with the Hardy-Weinberg law (P = 0.995), while a second field population was not at equilibrium (P less than 0.001).

  18. Differential recognition of geometric isomers by the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae): Evidence for only three essential components in aggregation pheromone.

    Science.gov (United States)

    Dickens, J C; Prestwich, G D

    1989-02-01

    For two decades, the aggregation pheromone of the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae), was thought to consist of four compounds: I [(+)-(Z)-2-isopropenyl-1-methylcyclobutane ethanol]; II [(Z)-3,3-dimethyl-Δ(I,β)-cyclohexane ethanol]; III [(Z)-3,3-dimethyl-Δ(1,α)-cyclohexane acetaldehyde); and IV [(E)-3,3-dimethyl-Δ(1,α)-cyclohexane acetaldehyde). Evidence is presented from behavioral and electrophysiological studies to show that only three of these components, I, II, and IV, are essential for attraction. Competitive field tests, in which each possible three-component blend was tested against the four-component mixture, demonstrated that omission of I, II. or IV resulted in decreased trap captures (P < 0.01). Trap captures by these blends lacking I, II, or IV resembled those by the hexane solvent alone in a similar experiment. However, omission of III did not significantly alter field attractiveness of the blend. Dosage-response curves constructed from electroantennogram responses of both males and females to serial dilutions of III, IV, and a 50∶50 mixture of the geometric isomers III and IV showed both sexes to be 10- to 100-fold more sensitive to IV than III. Data from the electrophysiological studies were consistent with a single acceptor type for the (E)-cyclohexylidene aldehyde, IV, for males, and possibly one or two acceptor types for III and IV for females. Possible roles for the (Z)-cyclohexylidene aldehyde, III, and implications for the pheromonal attractant currently used in boll weevil eradication/suppression programs are discussed.

  19. A diverse family of serine proteinase genes expressed in cotton boll weevil (Anthonomus grandis): implications for the design of pest-resistant transgenic cotton plants.

    Science.gov (United States)

    Oliveira-Neto, Osmundo B; Batista, João A N; Rigden, Daniel J; Fragoso, Rodrigo R; Silva, Rodrigo O; Gomes, Eliane A; Franco, Octávio L; Dias, Simoni C; Cordeiro, Célia M T; Monnerat, Rose G; Grossi-De-Sá, Maria F

    2004-09-01

    Fourteen different cDNA fragments encoding serine proteinases were isolated by reverse transcription-PCR from cotton boll weevil (Anthonomus grandis) larvae. A large diversity between the sequences was observed, with a mean pairwise identity of 22% in the amino acid sequence. The cDNAs encompassed 11 trypsin-like sequences classifiable into three families and three chymotrypsin-like sequences belonging to a single family. Using a combination of 5' and 3' RACE, the full-length sequence was obtained for five of the cDNAs, named Agser2, Agser5, Agser6, Agser10 and Agser21. The encoded proteins included amino acid sequence motifs of serine proteinase active sites, conserved cysteine residues, and both zymogen activation and signal peptides. Southern blotting analysis suggested that one or two copies of these serine proteinase genes exist in the A. grandis genome. Northern blotting analysis of Agser2 and Agser5 showed that for both genes, expression is induced upon feeding and is concentrated in the gut of larvae and adult insects. Reverse northern analysis of the 14 cDNA fragments showed that only two trypsin-like and two chymotrypsin-like were expressed at detectable levels. Under the effect of the serine proteinase inhibitors soybean Kunitz trypsin inhibitor and black-eyed pea trypsin/chymotrypsin inhibitor, expression of one of the trypsin-like sequences was upregulated while expression of the two chymotrypsin-like sequences was downregulated. Copyright 2004 Elsevier Ltd.

  20. Purification of a 6.5 kDa protease inhibitor from Amazon Inga umbratica seeds effective against serine proteases of the boll weevil Anthonomus grandis.

    Science.gov (United States)

    Calderon, L A; Teles, R C L; Leite, J R S A; Franco, O L; Grossi-de-Sá, M F; Medrano, F J; Bloch, C; Freitas, S M

    2005-08-01

    A 6.5 kDa serine protease inhibitor was purified by anion-exchange chromatography from the crude extract of the Inga umbratica seeds, containing inhibitor isoforms ranging from 6.3 to 6.7 kDa and protease inhibitors of approximately 19 kDa. The purified protein was characterized as a potent inhibitor against trypsin and chymotrypsin and it was named I. umbratica trypsin and chymotrypsin inhibitor (IUTCI). MALDI-TOF spectra of the IUTCI, in the presence of DTT, showed six disulfide bonds content, suggesting that this inhibitor belongs to Bowman-Birk family. The circular dichroism spectroscopy indicates that IUTCI is predominantly formed by unordered and beta-sheet secondary structure. It was also characterized, by fluorescence spectroscopy, as a stable protein at range of pH from 5.0 to 7.0. Moreover, this inhibitor at concentration of 75 microM presented a remarkable inhibitory activity (60%) against digestive serine proteases from boll weevil Anthonomus grandis, an important economical cotton pest.

  1. Distribution and probable physiological role of esterases in reproductive, digestive, and fat-body tissues of the adult cotton boll weevil, Anthonomus grandis Boh.

    Science.gov (United States)

    Jones, B R; Bancroft, H R

    1986-06-01

    Polyacrylamide gel electrophoresis was used to examine gut, Malpighian tube, fat-body, testes, and ovarioles tissues of the adult cotton boll weevil, Anthonomus grandis Boh. Esterases for which the inheritance has been reported previously by Terranova using whole-body homogenates were detected in dissected tissues and the probable physiological function of each allozyme is suggested. EST-1 occurs most frequently in ovarioles and female fat bodies. EST-2 is most often found in fat bodies and may be important in lipid turnover. No sex difference was observed. EST-3S is found in fat bodies and reproductive tissue, while EST-3F is always located in gut tissues, indicating that EST-3 is not controlled by a single autosomal locus with two codominant alleles as previously reported. EST-4, the most abundant esterase, can be detected in gut tissue at any age and is probably involved in digestion. EST-5 contains four allozymes which appear most frequently in testes and may be important during reproduction.

  2. Molecular cloning of alpha-amylases from cotton boll weevil, Anthonomus grandis and structural relations to plant inhibitors: an approach to insect resistance.

    Science.gov (United States)

    Oliveira-Neto, Osmundo B; Batista, João A N; Rigden, Daniel J; Franco, Octávio L; Falcão, Rosana; Fragoso, Rodrigo R; Mello, Luciane V; dos Santos, Roseane C; Grossi-de-Sá, Maria F

    2003-01-01

    Anthonomus grandis, the cotton boll weevil, causes severe cotton crop losses in North and South America. Here we demonstrate the presence of starch in the cotton pollen grains and young ovules that are the main A. grandis food source. We further demonstrate the presence of alpha-amylase activity, an essential enzyme of carbohydrate metabolism for many crop pests, in A. grandis midgut. Two alpha-amylase cDNAs from A. grandis larvae were isolated using RT-PCR followed by 5' and 3' RACE techniques. These encode proteins with predicted molecular masses of 50.8 and 52.7kDa, respectively, which share 58% amino acid identity. Expression of both genes is induced upon feeding and concentrated in the midgut of adult insects. Several alpha-amylase inhibitors from plants were assayed against A. grandis alpha-amylases but, unexpectedly, only the BIII inhibitor from rye kernels proved highly effective, with inhibitors generally active against other insect amylases lacking effect. Structural modeling of Amylag1 and Amylag2 showed that different factors seem to be responsible for the lack of effect of 0.19 and alpha-AI1 inhibitors on A. grandis alpha-amylase activity. This work suggests that genetic engineering of cotton to express alpha-amylase inhibitors may offer a novel route to A. grandis resistance.

  3. Seleção de isolados de Beauveria bassiana patogênicos ao bicudo-do-algodoeiro Selection of isolates of Beauveria bassiana pathogenic to cotton boll weevil

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Domingues da Silva

    2001-02-01

    Full Text Available Objetivou-se selecionar isolados de Beauveria bassiana (Balsamo Vüillemin provenientes de diferentes hospedeiros e regiões geográficas, patogênicos ao Anthonomus grandis, o bicudo-do-algodoeiro. Foram analisados 12 isolados em condições de laboratório. Os isolados obtidos originalmente de A. grandis foram pouco virulentos a essa praga. A mortalidade do bicudo teve início no segundo dia após a inoculação das suspensões fúngicas, variando de 15% a 83%, com TL50 entre 5,30 a 11,06 dias. Os isolados apresentaram variabilidade quanto à germinação dos conídios em meio de cultura artificial, e esta não se correlacionou com a patogenicidade. O isolado CG138 de B. bassiana destacou-se como um dos mais virulentos ao bicudo-do-algodoeiro.The objective of this work was to screen pathogenic isolates of Beauveria bassiana (Balsamo Vüillemin from different hosts and geographic regions, pathogenic to the cotton boll weevil. Twelve isolates were evaluated. Isolates originally obtained from boll weevil showed low pathogenicity against this host. Insect mortality began on the second day after inoculation by fungal suspension, ranging from 15% to 83%, with a TL50 of 5.30 to 11.06 days. Variability among isolates concerning conidial germination in artificial culture medium was verified, and TG50 did not correlate with pathogenicity. One of the most virulent isolates of B. bassiana against cotton boll weevil is CG138.

  4. Different processing of CAPA and pyrokinin precursors in the giant mealworm beetle Zophobas atratus (Tenebrionidae) and the boll weevil Anthonomus grandis grandis (Curculionidae).

    Science.gov (United States)

    Neupert, Susanne; Marciniak, Pawel; Köhler, Rene; Nachman, Ronald J; Suh, Charles P-C; Predel, Reinhard

    2018-03-01

    Capa and pyrokinin (pk) genes in hexapods share a common evolutionary origin. Using transcriptomics and peptidomics, we analyzed products of these genes in two beetles, the giant mealworm beetle (Zophobas atratus; Tenebrionidae) and the boll weevil (Anthonomus grandis grandis; Curculionidae). Our data revealed that even within Coleoptera, which represents a very well-defined group of insects, highly different evolutionary developments occurred in the neuropeptidergic system. These differences, however, primarily affect the general structure of the precursors and differential processing of mature peptides and, to a lesser degree, the sequences of the active core motifs. With the differential processing of the CAPA-precursor in Z. atratus we found a perfect example of completely different products cleaved from a single neuropeptide precursor in different cells. The CAPA precursor in abdominal ganglia of this species yields primarily periviscerokinins (PVKs) whereas processing of the same precursor in neurosecretory cells of the subesophageal ganglion results in CAPA-tryptoPK and a novel CAPA-PK. Particularly important was the detection of that CAPA-PK which has never been observed in the CNS of insects before. The three different types of CAPA peptides (CAPA-tryptoPK, CAPA-PK, PVK) each represent potential ligands which activate different receptors. In contrast to the processing of the CAPA precursor from Z. atratus, no indications of a differential processing of the CAPA precursor were found in A. g. grandis. These data suggest that rapid evolutionary changes regarding the processing of CAPA precursors were still going on when the different beetle lineages diverged. The sequence of the single known PVK of A. g. grandis occupies a special position within the known PVKs of insects and might serve asa basis to develop lineage-specific peptidomimetics capable of disrupting physiological processes regulated by PVKs. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Effect of Different Lignocellulosic Diets on Bacterial Microbiota and Hydrolytic Enzyme Activities in the Gut of the Cotton Boll Weevil (Anthonomus grandis).

    Science.gov (United States)

    Ben Guerrero, Emiliano; Soria, Marcelo; Salvador, Ricardo; Ceja-Navarro, Javier A; Campos, Eleonora; Brodie, Eoin L; Talia, Paola

    2016-01-01

    Cotton boll weevils, Anthonomus grandis , are omnivorous coleopteran that can feed on diets with different compositions, including recalcitrant lignocellulosic materials. We characterized the changes in the prokaryotic community structure and the hydrolytic activities of A. grandis larvae fed on different lignocellulosic diets. A. grandis larvae were fed on three different artificial diets: cottonseed meal (CM), Napier grass (NG) and corn stover (CS). Total DNA was extracted from the gut samples for amplification and sequencing of the V3-V4 hypervariable region of the 16S rRNA gene. Proteobacteria and Firmicutes dominated the gut microbiota followed by Actinobacteria, Spirochaetes and a small number of unclassified phyla in CM and NG microbiomes. In the CS feeding group, members of Spirochaetes were the most prevalent, followed by Proteobacteria and Firmicutes. Bray-Curtis distances showed that the samples from the CS community were clearly separated from those samples of the CM and NG diets. Gut extracts from all three diets exhibited endoglucanase, xylanase, β-glucosidase and pectinase activities. These activities were significantly affected by pH and temperature across different diets. We observed that the larvae reared on a CM showed significantly higher activities than larvae reared on NG and CS. We demonstrated that the intestinal bacterial community structure varies depending on diet composition. Diets with more variable and complex compositions, such as CS, showed higher bacterial diversity and richness than the two other diets. In spite of the detected changes in composition and diversity, we identified a core microbiome shared between the three different lignocellulosic diets. These results suggest that feeding with diets of different lignocellulosic composition could be a viable strategy to discover variants of hemicellulose and cellulose breakdown systems.

  6. Synthesis of 2,2,4,4-tetramethyl-N,N'-bis(2,6-dimethylphenyl)cyclobutane-1,3-diimine , a unique compound from Arundo donax, and its analogues to test their antifeedant activity against the boll weevil, Anthonomus grandis.

    Science.gov (United States)

    Mochizuki, K; Takikawa, H; Mori, K

    2000-03-01

    2,2,4,4-Tetramethyl-N,N'-bis(2,6-dimethylphenyl) cyclobutane-1,3-diimine (1), which was isolated from the Thai plant Arundo donax as an antifeedant against the boll weevil (Anthonomus grandis), and its analogues (9-13) were synthesized and shown to possess no remarkable antifeedant activity of practical interest.

  7. Mise en évidence de l'interconversion de l'acide abscissique et de l'abscissate de β-D-glucopyranose dans des feuilles de Vitis vinifera L. au cours de leur développement

    Directory of Open Access Journals (Sweden)

    Michel Broquedis

    1998-12-01

    Full Text Available L'évolution, dans les baies de raisin, de l'acide abscissique libre (ABA et de sa forme conjuguée, l'abscissate de β-D-glucopyranose (ABA-GE, est maintenant bien connue (BROQUEDIS, 1987. On sait notamment qu'une forte accumulation de ce régulateur de croissance sous sa forme libre se produit à la véraison et que l'interconversion entre les deux formes d'ASA est possible. Comme il est généralement admis que l'ASA est essentiellement synthétisé par les feuilles, il était intéressant de savoir si, chez la vigne, de tels phénomènes d'interconversion étaient susceptibles de se produire également dans ces organes, contrairement à l'opinion actuellement admise à la suite de travaux réalisés sur d'autres plantes.

  8. The Complexity of Posttranscriptional Small RNA Regulatory Networks Revealed by In Silico Analysis of Gossypium arboreum L. Leaf, Flower and Boll Small Regulatory RNAs.

    Directory of Open Access Journals (Sweden)

    Hongtao Hu

    Full Text Available MicroRNAs (miRNAs and secondary small interfering RNAs (principally phased siRNAs or trans-acting siRNAs are two distinct subfamilies of small RNAs (sRNAs that are emerging as key regulators of posttranscriptional gene expression in plants. Both miRNAs and secondary-siRNAs (sec-siRNAs are processed from longer RNA precursors by DICER-LIKE proteins (DCLs. Gossypium arboreum L., also known as tree cotton or Asian cotton, is a diploid, possibly ancestral relative of tetraploid Gossypium hirsutum L., the predominant type of commercially grown cotton worldwide known as upland cotton. To understand the biological significance of these gene regulators in G. arboreum, a bioinformatics analysis was performed on G. arboreum small RNAs produced from G. arboreum leaf, flower, and boll tissues. Consequently, 263 miRNAs derived from 353 precursors, including 155 conserved miRNAs (cs-miRNAs and 108 novel lineage-specific miRNAs (ls-miRNAs. Along with miRNAs, 2,033 miRNA variants (isomiRNAs were identified as well. Those isomiRNAs with variation at the 3'-miRNA end were expressed at the highest levels, compared to other types of variants. In addition, 755 pha-siRNAs derived 319 pha-siRNA gene transcripts (PGTs were identified, and the potential pha-siRNA initiators were predicted. Also, 2,251 non-phased siRNAs were found as well, of which 1,088 appeared to be produced by so-called cis- or trans-cleavage of the PGTs observed at positions differing from pha-siRNAs. Of those sRNAs, 148 miRNAs/isomiRNAs and 274 phased/non-phased siRNAs were differentially expressed in one or more pairs of tissues examined. Target analysis revealed that target genes for both miRNAs and pha-siRNAs are involved a broad range of metabolic and enzymatic activities. We demonstrate that secondary siRNA production could result from initial cleavage of precursors by both miRNAs or isomiRNAs, and that subsequently produced phased and unphased siRNAs could result that also serve as triggers

  9. The Complexity of Posttranscriptional Small RNA Regulatory Networks Revealed by In Silico Analysis of Gossypium arboreum L. Leaf, Flower and Boll Small Regulatory RNAs.

    Science.gov (United States)

    Hu, Hongtao; Rashotte, Aaron M; Singh, Narendra K; Weaver, David B; Goertzen, Leslie R; Singh, Shree R; Locy, Robert D

    2015-01-01

    MicroRNAs (miRNAs) and secondary small interfering RNAs (principally phased siRNAs or trans-acting siRNAs) are two distinct subfamilies of small RNAs (sRNAs) that are emerging as key regulators of posttranscriptional gene expression in plants. Both miRNAs and secondary-siRNAs (sec-siRNAs) are processed from longer RNA precursors by DICER-LIKE proteins (DCLs). Gossypium arboreum L., also known as tree cotton or Asian cotton, is a diploid, possibly ancestral relative of tetraploid Gossypium hirsutum L., the predominant type of commercially grown cotton worldwide known as upland cotton. To understand the biological significance of these gene regulators in G. arboreum, a bioinformatics analysis was performed on G. arboreum small RNAs produced from G. arboreum leaf, flower, and boll tissues. Consequently, 263 miRNAs derived from 353 precursors, including 155 conserved miRNAs (cs-miRNAs) and 108 novel lineage-specific miRNAs (ls-miRNAs). Along with miRNAs, 2,033 miRNA variants (isomiRNAs) were identified as well. Those isomiRNAs with variation at the 3'-miRNA end were expressed at the highest levels, compared to other types of variants. In addition, 755 pha-siRNAs derived 319 pha-siRNA gene transcripts (PGTs) were identified, and the potential pha-siRNA initiators were predicted. Also, 2,251 non-phased siRNAs were found as well, of which 1,088 appeared to be produced by so-called cis- or trans-cleavage of the PGTs observed at positions differing from pha-siRNAs. Of those sRNAs, 148 miRNAs/isomiRNAs and 274 phased/non-phased siRNAs were differentially expressed in one or more pairs of tissues examined. Target analysis revealed that target genes for both miRNAs and pha-siRNAs are involved a broad range of metabolic and enzymatic activities. We demonstrate that secondary siRNA production could result from initial cleavage of precursors by both miRNAs or isomiRNAs, and that subsequently produced phased and unphased siRNAs could result that also serve as triggers of a second

  10. Mutantes morfológicos de algodoeiro herbáceo como fonte de resistência ao bicudo Morphological mutants of upland cotton as source of boll weevil resistance

    Directory of Open Access Journals (Sweden)

    Francisco das Chagas Vidal Neto

    2005-02-01

    Full Text Available Este trabalho teve como objetivo avaliar os efeitos de três características morfológicas mutantes de linhagens de algodoeiro herbáceo (Gossypium hirsutum L. r. latifolium Hutch., isoladas ou combinadas no mesmo genótipo, como fonte de resistência ao bicudo, Anthonomus grandis Boheman, 1843 (Coleoptera, Curculionidae. O experimento foi conduzido em campo, sob infestação natural, com delineamento de blocos ao acaso e arranjo fatorial 2´3 com um tratamento adicional, com quatro repetições. Em teste com chance de escolha, a característica bráctea frego foi a que apresentou maior redução no dano de oviposição pelo bicudo (34,71%, em relação ao equivalente normal. A folha "okra" reduziu o dano apenas quando associada à bráctea frego (40%. A combinação das três características mutantes na mesma planta proporcionou a menor porcentagem de botões com dano de oviposição (23,13%.This work aimed to evaluate the effects of three morphological mutants of upland cotton lines (Gossypium hirsutm L. r. latifolium Hutch., isolated or in combination in the same cotton genotype, as a source of resistance to boll weevil, Anthonomus grandis Boheman, 1843 (Coleoptera, Curculionidae. The experiment was carried out in the field, under natural infestation, with a completely randomized block design arranged in a factorial 2´3 plus an additional treatment, with four replications. In a multiple choice test, the character mutant frego bract presented the higher reduction on boll weevil oviposition damage (34.71%, in relation to the normal equivalent. The okra leaf reduced the boll weevil damage only when associated with frego bract (40%. The combination of the three mutant characters in the same plant presented the least square percent with oviposition damage (23.13%.

  11. CARACTERÍSTICAS DO CAPULHO E PROPRIEDADES TECNOLÓGICAS DA FIBRA DO ALGODOEIRO EM FUNÇÃO DA CALAGEM E DA GESSAGEM BOLLS CHARACTERISTICS AND TECHNOLOGICAL PROPERTIES OF THE COTTON FIBER FACING OF LIMESTONE AND PHOSPHOGYPSUM

    Directory of Open Access Journals (Sweden)

    NELSON PAULIERI SABINO

    1998-01-01

    Full Text Available Em latossolo roxo ácido e de baixa fertilidade do município de Guaíra (SP, desenvolveu-se de 1986/87 a 1989/90 um ensaio de caráter permanente com o algodoeiro para estudar o efeito da aplicação de calcário (0,6; 1,8 e 3,0 t.ha-1 e de gesso (0, 2, 4, 6 t.ha-1 sobre as características do capulho e propriedades tecnológicas da fibra. O delineamento experimental utilizado foi do tipo blocos ao acaso com parcelas subsubdivididas e quatro repetições. O calcário elevou os valores de massa de um capulho e diminuiu o índice Micronaire e a maturidade da fibra, mas não afetou a massa de sementes, a porcentagem, o comprimento, a uniformidade de comprimento e a tenacidade da fibra. O gesso aumentou as massas de capulho e de sementes, especialmente quando associado a maior dose de calcário, assim como o índice Micronaire e a maturidade da fibra, no mais baixo nível de calagem.The effects of limestone and phosphogypsum applications on bolls characteristics and technological properties of the cotton fiber were studied in a permanent trial on a Dystrophic Dusky Latosol, acid and of low fertility during growing seasons of 1986/87 to 1989/90. A randomized complete block design was used, arranged in split split-plots with four replications where the dolomitic limestone doses were the main plots (0.6, 1.8 and 3.0 t.ha-1, and the phosphogypsum doses (0, 2, 4, and 6 t.ha-1 were the subplots. Lime and phosphogypsum were applied in the first year and reaplicated during 1988/89. Liming caused an increase in mass of bolls and reduced the Micronaire index and fiber maturity, and did not affect the mass of seed, the percentage of fiber, the length, the length uniformity and fiber tenacity. The use of phosphogypsum increase the mass of bolls and mass of seed, mainly when associated with extremes doses of lime. Otherwise, its effects upon Micronaire index and fiber maturity values, were significant at low level of liming.

  12. Effect of diameter of the cotton squares in the development of boll weevil Efeito do diâmetro do botão floral no desenvolvimento do bicudo-do-algodoeiro

    Directory of Open Access Journals (Sweden)

    Marcos Doniseti Michelotto

    2007-01-01

    Full Text Available The objective of this work was to study the effect of diameter of the cotton squares in the corporal mass of adults of boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae. The assay was carried out under field and laboratory conditions, in Jaboticabal, São Paulo State, Brazil. Six samplings obtained from a random harvesting of ten plants of each cultivar (Coodetec 405 and Fibermax 986. The number and diameter of squares were recorded for each plant. Squares with oviposition orifices were kept individually in a recipient and observed daily until adult emergence. The larger the diameter of the squares, the more corporal mass of boll weevil newly emerged adults in both cultivars.O objetivo deste trabalho foi estudar o efeito do diâmetro dos botões florais de algodoeiro na massa corporal de adultos do bicudo-do-algodoeiro, Anthonomus grandis Boheman (Coleoptera: Curculionidae. O experimento foi realizado em condições de campo e laboratório, em Jaboticabal (SP, Brasil. Foram realizadas seis amostragens, coletando-se ao acaso dez plantas nas cultivares Coodetec 405 e Fibermax 986, avaliando-se o número e o diâmetro de botões florais. Os botões florais com orifícios de oviposição foram individualizados em frascos e observados diariamente para a visualização da emergência dos adultos. Botões florais com maiores diâmetros proporcionam maior massa corporal de adultos de A. grandis recém-emergidos nas duas cultivares.

  13. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae) in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae) =Efeito da pilhagem de néctar por abelhas nativas sem ferrão (Hymenoptera: Apidae) na abscisão floral de Bougainvillea spectabilis Willd. (Nyctaginaceae)

    OpenAIRE

    Rodrigo Arand; Gisele Catian; Paulo Alexandre Bogiani; Igor Inforzato

    2011-01-01

    This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbe...

  14. El picudo del algodonero en la Argentina: Principales resultados e implicancias de los estudios moleculares The cotton boll weevil in Argentina: Main results and implications of the molecular studies

    Directory of Open Access Journals (Sweden)

    Analía A. Lanteri

    2003-12-01

    the cotton boll weevil, Anthonomus grandis Boheman (Coleoptera, Curculionidae, in Argentina, the insect arrived in the cotton area of Chaco. Molecular studies on populations from Argentina, Brazil and Paraguay, and possible source populations from USA and Mexico, provided helpful information to control the pest. RAPD technique (Random Analysis of Polymorphic DNA and sequencing of Cytochrome Oxidase I and II mitochondrial genes, allowed to differentiate two main lineages: a lineages with scarce or null variability measured by heterocigosis and haplotypic diversity, considered recent colonizers, and associated with xerophytic environments and cotton areas (Formosa province; b lineages with high genetic variability and haplotypic diversity, considered ancestral, and associated with areas of wild vegetation as the subtropical forests of Misiones (Iguazú National Park. Both lineages probably have different origins, adaptations and host preferences, and at present would be hibridizing in ecotonal areas. We propose that the boll weevil probably occurs in South America as a consequence of a natural dispersal associated to wild hosts, mainly of the genera Gossypium and Cienfuegosia, probably since Pleistocene times. On the other hand, there is a possibility of introductions from USA to Brazil, trough the commercial exchange. Extensive cotton cultivation and deforestation, with formation of corridors connecting fragments of forests would explain the rapid dispersal of the pest during the last 20 years, in cotton and/or non cotton areas under environmental impact, such as the Misiones province.

  15. Contenido de los nutrientes básicos en Catolaccus grandis Burks criados sobre larvas del picudo del algodon Basic nutrients content of Catolaccus grandis Burks reared in cotton boll weevil larvae

    Directory of Open Access Journals (Sweden)

    LÚCIA HELENA AVELINO ARAUJO

    2000-09-01

    Full Text Available El objetivo del trabajo fue determinar los niveles de carbohidratos, proteínas solubles y aminoácidos libres de larvas, pupas hembras y adultos hembras de Catolaccus grandis (Burks (Hymenoptera: Pteromalidae criados sobre larvas del picudo del algodón envenenadas por hembras del parasitoide y por larvas de primer instar del parasitoide. Esto estudio fue conducido en la Unidade de Investigación de Control Biologico de Plagas del Departamento de Agricultura de los Estados Unidos de la América, en Weslaco, Texas. Las 20 muestras de cada uno de los tres estados de desarrollo: tercer instar larval, pupas hembra y adultos hembra del parasitoide C. grandis, fueron separadas y pesadas individualmente y se cuantió el contenido de carbohidratos totales, proteínas solubles totales y aminoácidos libres criados en diferentes sustratos. Los resultados obtenidos confirman la existencia de patrones metabólicos significativamente distintos de estos nutrientes básicos.The aim of this work was to determine the levels of carbohydrate, soluble proteins and free amino acids of larvae, pupae and adult females Catolaccus grandis Burks (Hymenoptera: Pteromalidae which were reared in cotton (Gossypium hirsutum L. r. latifolium Hutch boll weevil (Anthonomus grandis larvae venomized by ectoparasitoid of female and 1st instar ectoparasitoid larvae. This study was carried out at the Biological Control of Pests Research Unit, Weslaco, Texas. The twenty samples of each one of three stages of development: 3rd instar larval, female pupae and female adult of parasitoid C. grandis were separated and individually weighted, and levels of carbohydrates, proteins and amino acids were quantified when reared in different substrates. The results confirmed the existence of metabolic patterns significantly distinct from the basic nutrient model.

  16. The effect of calcium on auxin depletion-induced tomato ...

    African Journals Online (AJOL)

    Indole-3-acetic acid (IAA) and calcium are the most important factors that instigate plant organ abscission. This study aimed to elucidate the mechanisms that underlie the effects of IAA and calcium on delayed abscission in tomato. The results showed a clear trend towards reduced abscission rates with increased ...

  17. Método de diagnóstico para el monitoreo de resistencia a insecticidas en poblaciones de "picudo del algodonero", Anthonomus grandis (Coleoptera: Curculionidae A diagnostic test for insecticide resistance monitoring in "cotton boll weevil" Anthonomus grandis (Coleoptera: Curculionidae populations

    Directory of Open Access Journals (Sweden)

    Teodoro Stadler

    2009-06-01

    Full Text Available El control de las poblaciones de Anthonomus grandis Boheman, por debajo de su umbral de daño económico durante el ciclo del cultivo del algodón, se realiza en forma efectiva hasta el momento, a través de insecticidas de síntesis. La presión selectiva de las aplicaciones extensivas e intensivas de insecticidas hace imperativa la detección temprana de focos de resistencia a los mismos, en función de un correcto manejo del fenómeno. Se desarrolló un método de diagnóstico de resistencia para A. grandis a partir de la técnica "vial test", que fue adaptada en forma de "kit" para el monitoreo rápido y sencillo de los focos de resistencia en el campo. La toxicidad (CL99, para calcular la concentración discriminante (CD del insecticida y la preparación del "kit", se obtiene a partir de bioensayos de laboratorio con una cepa normal susceptible de A. grandis. Se determinó la vida media de los insecticidas dentro de los viales por CIPAC MT 46, para establecer una fecha de vencimiento del "kit". La CD y el método en su conjunto fueron validados a través de ensayos a campo. El "kit", usado en el monitoreo de resistencia en el campo, fue especialmente diseñado para ser utilizado en las condiciones geográficas, económicas y socio-culturales presentes en la región algodonera argentina. La implementación de esta técnica permitirá conseguir la información necesaria, y así obtener una apropiada alternancia de insecticidas. Como consecuencia, se prevé una reducción de impacto ambiental de las prácticas agronómicas en el control de plagas en algodón.The in-season control of the cotton boll weevil Anthonomus grandis Boheman is done by insecticide application, which so far is the only effective way to reduce boll weevil populations to levels below economic significance. The extensive and intensive control actions with insecticides cause selective pressure on pest populations. Thus, to achieve an accurate insecticide resistance

  18. Germination rate is the significant characteristic determining coconut palm diversity.

    Science.gov (United States)

    Harries, Hugh C

    2012-01-01

    This review comes at a time when in vitro embryo culture techniques are being adopted for the safe exchange and cryo-conservation of coconut germplasm. In due course, laboratory procedures may replace the options that exist among standard commercial nursery germination techniques. These, in their turn, have supplanted traditional methods that are now forgotten or misunderstood. Knowledge of all germination options should help to ensure the safe regeneration of conserved material. This review outlines the many options for commercial propagation, recognizes the full significance of one particular traditional method and suggests that the diversity of modern cultivated coconut varieties has arisen because natural selection and domestic selection were associated with different rates of germination and other morphologically recognizable phenotypic characteristics. The review takes into account both the recalcitrant and the viviparous nature of the coconut. The ripe fruits that fall but do not germinate immediately and lose viability if dried for storage are contrasted with the bunches of fruit retained in the crown of the palm that may, in certain circumstances, germinate to produce seedlings high above ground level. Slow-germinating and quick-germinating coconuts have different patterns of distribution. The former predominate on tropical islands and coastlines that could be reached by floating when natural dispersal originally spread coconuts widely-but only where tides and currents were favourable-and then only to sea-level locations. Human settlers disseminated the domestic types even more widely-to otherwise inaccessible coastal sites not reached by floating-and particularly to inland and upland locations on large islands and continental land masses. This review suggests four regions where diversity has been determined by germination rates. Although recent DNA studies support these distinctions, further analyses of genetic markers related to fruit abscission and

  19. Germination rate is the significant characteristic determining coconut palm diversity

    Science.gov (United States)

    Harries, Hugh C.

    2012-01-01

    Rationale This review comes at a time when in vitro embryo culture techniques are being adopted for the safe exchange and cryo-conservation of coconut germplasm. In due course, laboratory procedures may replace the options that exist among standard commercial nursery germination techniques. These, in their turn, have supplanted traditional methods that are now forgotten or misunderstood. Knowledge of all germination options should help to ensure the safe regeneration of conserved material. Scope This review outlines the many options for commercial propagation, recognizes the full significance of one particular traditional method and suggests that the diversity of modern cultivated coconut varieties has arisen because natural selection and domestic selection were associated with different rates of germination and other morphologically recognizable phenotypic characteristics. The review takes into account both the recalcitrant and the viviparous nature of the coconut. The ripe fruits that fall but do not germinate immediately and lose viability if dried for storage are contrasted with the bunches of fruit retained in the crown of the palm that may, in certain circumstances, germinate to produce seedlings high above ground level. Significance Slow-germinating and quick-germinating coconuts have different patterns of distribution. The former predominate on tropical islands and coastlines that could be reached by floating when natural dispersal originally spread coconuts widely—but only where tides and currents were favourable—and then only to sea-level locations. Human settlers disseminated the domestic types even more widely—to otherwise inaccessible coastal sites not reached by floating—and particularly to inland and upland locations on large islands and continental land masses. This review suggests four regions where diversity has been determined by germination rates. Although recent DNA studies support these distinctions, further analyses of genetic markers

  20. Seed cotton yield, ionic and quality attributes of two cotton (Gossypium hirsutum L. varieties as influenced by various rates of K and Na under field conditions

    Directory of Open Access Journals (Sweden)

    Muhammad Sohail

    2011-11-01

    Full Text Available Cotton is more sensitive to low K availability than most other major field crops, and often shows symptoms of K deficiency in soils not considered K deficient. Field investigation was conducted at Sahiwal to study the effect of different rates of K and Na application on seed cotton yield, ionic ratio and quality characteristics of two cotton varieties. Ten soil K: Na ratios were developed after considering indigenous K, Na status in soil. The treatments of K+Na in kg ha-1 to give K:Na ratios were as: 210+ 60 (3.5:1 i.e. control, 225 + 60 (3.75:1, 240 + 60 (4:1, 255 + 60 (4.25:1, 270 + 60 (4.5:1, 210 + 75 (2.8:1, 225 + 75 (3:1, 240 + 75 (3.2:1, 255 + 75 (3.4:1 and 270 + 75 (3.6:1. Control treatment represented indigenous K, Na status of soil. The experiment continued until maturity. Maximum seed cotton yield of NIBGE-2 was observed at K: Na ratio of 3.6:1. Variety NIBGE-2 manifested greater seed cotton yield than MNH-786. Leaf K: Na ratio of two cotton varieties differed significantly (p < 0.01 due to varieties, rates of K and Na and their interaction. Variety NIBGE-2 maintained higher K: Na ratio than MNH-786 and manifested good fiber quality. There was significant relationship (R2 = 0.55, n = 10 between K: Na ratio and fiber length and significant relationship (R2 = 0.65, n = 10 between K concentration and fiber length for NIBGE-2. There was also significant relationship (R2 = 0.91, 0.78, n = 10 between boll number and seed cotton yield for both varieties. The increase in yield was attributed to increased boll weight.

  1. Ratings Revisited

    DEFF Research Database (Denmark)

    Lai, Signe Sophus

    2015-01-01

    tværs af medier og platforme, forskudt i tid og on-demand. This article focuses on audience ratings, which have functioned as the central ‘currency’ informing the media trade. It discusses changes to the production and accuracy of audience ratings at a time when established standards are being...

  2. Efeitos da utilização de misturas de adubos com ou sem enxofre na precocidade e nas características do capulho e da fibra do algodoeiro Effects of mixtures of fertilizers with or without sulfur on cotton earliness and some characteristics of fibers and bolls

    Directory of Open Access Journals (Sweden)

    Nelson Paulieri Sabino

    1984-01-01

    Full Text Available São apresentados resultados referentes à precocidade e características do capulho e da fibra do algodoeiro, obtidos em ensaio de caráter permanente, no município de Guaíra (SP, em gleba de Latossolo Roxo, durante o período 1974/75-1977/78, utilizando-se a variedade 'IAC 16'. Além da reação ao fósforo, foi planejado um estudo conjunto visando observar a resposta do algodoeiro à aplicação de misturas de adubo contendo fósforo e enxofre em quantidades variáveis. A análise e a interpretação dos resultados permitiram as seguintes conclusões: a Adubações com superfosfato triplo ou simples, em solo deficiente em fósforo, resultaram em maior precocidade no ciclo do algodoeiro, enquanto o uso de sulfato de amônio em cobertura tendeu a prolongar esse ciclo; b Ambas as fontes citadas de fósforo proporcionaram aumentos significativos no peso de capulho e no comprimento das fibras, enquanto apenas o superfosfato simples aumentou sensivelmente o peso de cem sementes e o índice Micronaire, que representa o complexo finura + maturidade da fibra; c As características porcentagem de fibras, uniformidade de comprimento, resistência e maturidade das fibras, não foram alteradas significativamente pelos tratamentos estudados.Effects of fertilizers mixtures with or without sulfur on cotton earliness and some characteristics of fiber and bolls, obtained in a field experiment carried out at Guaira County (SP in a oxisoil -"Latossolo Roxo" - during the years of 1974/75 to 1977/78, are related. The following conclusions can be drawn from the results: a - soil fertilizations with concentrated superphosphate or ordinary superphosphate resulted in early picking of cotton crop. Plant cycle, was delayed with split application of ammonium sulphate; b - both concentrated superphosphate and ordinary superphosphate increased significantly boll weight and fiber length, but only ordinary superphosphate gave significant increases on seed weights and

  3. Streamflow ratings

    Science.gov (United States)

    Holmes, Robert R.; Singh, Vijay P.

    2016-01-01

    Autonomous direct determination of a continuous time series of streamflow is not economically feasible at present (2014). As such, surrogates are used to derive a continuous time series of streamflow. The derivation process entails developing a streamflow rating, which can range from a simple, single-valued relation between stage and streamflow to a fully dynamic one-dimensional model based on hydraulics of the flow.

  4. Rate theory

    International Nuclear Information System (INIS)

    Maillard, S.; Skorek, R.; Maugis, P.; Dumont, M.

    2015-01-01

    This chapter presents the basic principles of cluster dynamics as a particular case of mesoscopic rate theory models developed to investigate fuel behaviour under irradiation such as in UO 2 . It is shown that as this method simulates the evolution of the concentration of every type of point or aggregated defect in a grain of material. It produces rich information that sheds light on the mechanisms involved in microstructure evolution and gas behaviour that are not accessible through conventional models but yet can provide for improvements in those models. Cluster dynamics parameters are mainly the energetic values governing the basic evolution mechanisms of the material (diffusion, trapping and thermal resolution). In this sense, the model has a general applicability to very different operational situations (irradiation, ion-beam implantation, annealing) provided that they rely on the same basic mechanisms, without requiring additional data fitting, as is required for more empirical conventional models. This technique, when applied to krypton implanted and annealed samples, yields a precise interpretation of the release curves and helps assess migration mechanisms and the krypton diffusion coefficient, for which data is very difficult to obtain due to the low solubility of the gas. (authors)

  5. Saussurea involucrata SiDhn2 gene confers tolerance to drought stress in upland cotton

    International Nuclear Information System (INIS)

    Liu, B.; Zhu, J.; Mu, J.; Zhu, J.; Liang, Z.; Zhang, L.

    2017-01-01

    Severe water shortage has long been acknowledged as one major limiting factor for global cotton production, and cultivation of cotton varieties with strong drought resistance is of important economic and social significances. In this study, the Xinjiang upland cotton variety Xinluzao 42 was transformed with the SiDhn2 gene by optimized agrobacterium transformation system. The integration of SiDhn2 gene into cotton genome was confirmed by PCR and Southern blot hybridization, and the drought resistance of transgenic and corresponding receptor cotton plants and their physiological indexes under drought stress were detailedly analyzed. Multiple physiological and biochemical indexes including soluble sugar content, free proline content, chlorophyll content, relative water content, net photosynthetic rate, transpiration rate, intercellular CO/sub 2/ concentration in transgenic cotton expressing SiDhn2 gene under drought stress were significantly higher than those of receptor cotton. More importantly, the transgenic cotton plants exhibited remarkably decreased boll abscission rate and highly increased seed yield, indicating the significant role of SiDhn2 gene in cotton drought resistance and its great application potential in agricultural production. (author)

  6. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae =Efeito da pilhagem de néctar por abelhas nativas sem ferrão (Hymenoptera: Apidae na abscisão floral de Bougainvillea spectabilis Willd. (Nyctaginaceae

    Directory of Open Access Journals (Sweden)

    Rodrigo Arand

    2011-09-01

    Full Text Available This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and nonrobber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear regression was used to see whether there was a relationship between the closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant. There were significant differences regarding all variables measured between soil and plant.A correlation was found at both closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant.O presente trabalho teve como objetivo avaliar a atividade de pilhagemde abelhas nativas influenciando a abscisão floral de Bougainvillea spectabilis. As coletas foram realizadas em dez indivíduos de B. spectabilis. Foram coletadas 2.874 flores no solo e 2.895 na planta no período de 4/5/2009 a 1/6/2009 com intervalo de três dias entre cada coleta, totalizando 10 repetições em cada indivíduo. Foram mensuradas as flores fechadas, flores abertas, flores fechadas pilhadas, flores fechadas não pilhadas, flores abertas pilhadas e flores abertas não pilhadas tanto no solo como na planta. Para as análises estatísticas foi utilizado o Teste-T para verificar se houve diferença entre as médias obtidas das características avaliadas entre as flores do solo e as

  7. Effect of different rates of potassium fertilizer on nitrogen use efficiency and cotton yield using an 15N isotopic dilution technique

    International Nuclear Information System (INIS)

    Khalifa, Kh.; Al-Chamma'a, M.; Al-Ain, F.

    2005-03-01

    A field study was carried out during the 2003 growing season on a loamy to sandy clay loamy soil, located at the Lower Euphrate's Valley, 15 km southeast of Deir - Ezzor city to evaluate the effect of K fertilizer on nitrogen , potassium use efficiency and cotton yield. Three nitrogen ( N1 =120, N2 =180, and N3 = 240 kg N / ha ) and four potassium application rates ( K0 = 0 , K1 = 50, K2 = 100, K3 = 150 kg K2O / ha ) were employed. The cotton variety was Deir 22 sown on April 2003 at a spacing of 70 cm between rows and 20 cm between pits with 5 seeds per pit. The plants were thinned to 2 plants per pit 4 weeks after planting. Representative samples of aboveground portions of cotton plants were harvested from labeled subplots at 108 and 161 days after planting . Dry matter weight , N uptake, N fertilizer yield, N use efficiency, K use efficiency, seed cotton yield, earliness, leaf area, number of bolls / plant, and number of branches / plant were evaluated. The results showed that seed cotton yield increased with increasing K levels applied under each rate of N ( except N120 ). The highest seed cotton yield was obtained with the combined treatment N3K1 ( 6442 kg/ha ). This treatment gave also the optimum potassium use efficiency ( 42 % ). Nitrogen use efficiency (at 180 days of harvest ) increased with the increasing K application rate. Nitrogen use efficiency (NUE) was decreased with increasing N rates . Increasing K application rate ( KUE ) decreased potassium use efficiency. A maximum N use efficiency ( 98% ) was obtained for combined treatment N2 K3. Also the results indicated that dry matter weight and N uptake increased with increasing K rates applied. Nitrogen derived from fertilizer (Ndff ) was higher in combined treatments than the control treatments (K0 ). (Authors)

  8. Heart rate index

    DEFF Research Database (Denmark)

    Haedersdal, C; Pedersen, F H; Svendsen, J H

    1992-01-01

    after the myocardial infarction. A significant correlation (Spearman's correlation coefficient rs, p less than 0.05) was found between LVEF at rest and the following variables assessed at exercise test: 1) the heart rate at rest, 2) rise in heart rate, 3) ratio between maximal heart rate and heart rate...... at rest, 4) rise in systolic blood pressure, 5) rate pressure product at rest, 6) rise in rate pressure product, 7) ratio (rHR) between maximal rate pressure product and rate pressure product at rest, 8) total exercise time. The heart rate was corrected for effects caused by age (heart index (HR...

  9. Real Property Tax Rates

    Data.gov (United States)

    Montgomery County of Maryland — The Levy Year 2012 real property tax rate dataset reflects all the rates per $100 set each year by the County Council. These rates are applied to the assessed value...

  10. Variable-Rate Premiums

    Data.gov (United States)

    Pension Benefit Guaranty Corporation — These interest rates are used to value vested benefits for variable rate premium purposes as described in PBGC's regulation on Premium Rates (29 CFR Part 4006) and...

  11. Rating Movies and Rating the Raters Who Rate Them.

    Science.gov (United States)

    Zhou, Hua; Lange, Kenneth

    2009-11-01

    The movie distribution company Netflix has generated considerable buzz in the statistics community by offering a million dollar prize for improvements to its movie rating system. Among the statisticians and computer scientists who have disclosed their techniques, the emphasis has been on machine learning approaches. This article has the modest goal of discussing a simple model for movie rating and other forms of democratic rating. Because the model involves a large number of parameters, it is nontrivial to carry out maximum likelihood estimation. Here we derive a straightforward EM algorithm from the perspective of the more general MM algorithm. The algorithm is capable of finding the global maximum on a likelihood landscape littered with inferior modes. We apply two variants of the model to a dataset from the MovieLens archive and compare their results. Our model identifies quirky raters, redefines the raw rankings, and permits imputation of missing ratings. The model is intended to stimulate discussion and development of better theory rather than to win the prize. It has the added benefit of introducing readers to some of the issues connected with analyzing high-dimensional data.

  12. Interest rate derivatives

    DEFF Research Database (Denmark)

    Svenstrup, Mikkel

    This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered.......This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered....

  13. Airline Quality Rating 1996

    OpenAIRE

    Bowen, Brent D.; Headley, Dean E.

    1996-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple factors important to consumers. Development history and calculation details for the AQR rating system are detailed in The Airline Quality Rating issued in April, 1991, by the National Institute for Aviation Research at Wichita State University. This current report, Airline Quality Rating 1996, contains monthly Airline Quality Rating scor...

  14. Irradiated boll weevils: pheromone production determined by GLC analysis

    International Nuclear Information System (INIS)

    McGovern, W.L.; McKibben, G.H.; Gueldner, R.C.; Cross, W.H.

    1975-01-01

    The production of pheromone by Anthonomus grandis Boheman when treated with 10,000 rad of 60 Co gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from day one. No direct correlation was found between production of pheromone and elimination of frass

  15. The rating reliability calculator

    Directory of Open Access Journals (Sweden)

    Solomon David J

    2004-04-01

    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.

  16. Labor Force Participation Rate

    Data.gov (United States)

    City and County of Durham, North Carolina — This thematic map presents the labor force participation rate of working-age people in the United States in 2010. The 2010 Labor Force Participation Rate shows the...

  17. Rate Review Data

    Data.gov (United States)

    U.S. Department of Health & Human Services — As of September 1, 2011, the Affordable Care Act and rate review regulation require review of rate increases of 10 percent or more. A non-grandfathered health plan...

  18. Interest Rates and Inflation

    OpenAIRE

    Coopersmith, Michael; Gambardella, Pascal J.

    2016-01-01

    This article is an extension of the work of one of us (Coopersmith, 2011) in deriving the relationship between certain interest rates and the inflation rate of a two component economic system. We use the well-known Fisher relation between the difference of the nominal interest rate and its inflation adjusted value to eliminate the inflation rate and obtain a delay differential equation. We provide computer simulated solutions for this equation over regimes of interest. This paper could be of ...

  19. Interest Rate Swaps

    OpenAIRE

    Marina Pepic

    2014-01-01

    Interest rates changes have a huge impact on the business performance. Therefore, it is of great importance for the market participants to identify and adequately manage this risk. Financial derivatives are a relatively simple way of protection from adverse changes in interest rates. Interest rate swaps are particularly popular because they reduce interest rate risk to a minimum with a relatively low initial cost and without great risk, but also because of the fact that there are many modific...

  20. Understanding Interest Rate Volatility

    OpenAIRE

    Volker, Desi

    2016-01-01

    This thesis is the result of my Ph.D. studies at the Department of Finance of the Copenhagen Business School. It consists of three essays covering topics related to the term structure of interest rates, monetary policy and interest rate volatility. The rst essay, \\Monetary Policy Uncertainty and Interest Rates", examines the role of monetary policy uncertainty on the term structure of interest rates. The second essay, \\A Regime-Switching A ne Term Structure Model with Stochast...

  1. Airline Quality Rating 2003

    OpenAIRE

    Bowen, Brent D.; Headley, Dean E.

    2003-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline quality on combined multiple performance criteria. This current report, the Airline Quality Rating 2003, reflects monthly Airline Quality Rating scores for 2002. AQR scores for the calendar year 2002 are based on 15 elements that focus on airline performance areas important to air travel consumers. The Airline Quality Rating 2003 is a summary of month-by-month qualit...

  2. Airline Quality Rating 2001

    OpenAIRE

    Bowen, Brent D.; Headley, Dean E.

    2001-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline quality on combined multiple performance criteria. This current report, Airline Quality Rating 2001, reflects monthly Airline Quality Rating scores for 2000. AQR scores for the calendar year 2000 are based on 15 elements that focus on airline performance areas important to air travel consumers. The Airline Quality Rating 2001 is a summary of month-by-month quality ra...

  3. Thermonuclear reaction rates. III

    International Nuclear Information System (INIS)

    Harris, M.J.; Fowler, W.A.; Caughlan, G.R.; Zimmerman, B.A.

    1983-01-01

    Stellar thermonuclear reaction rates are revised and updated, adding a number of new important reaction rates. Several reactions with large negative Q-values are included, and examples of them are discussed. The importance of the decay rates for Mg-26(p,n) exp 26 Al and Al-26(n,p) exp 26 Mg for stellar studies is emphasized. 19 references

  4. Resonant thermonuclear reaction rate

    International Nuclear Information System (INIS)

    Haubold, H.J.; Mathai, A.M.

    1986-01-01

    Basic physical principles for the resonant and nonresonant thermonuclear reaction rates are applied to find their standard representations for nuclear astrophysics. Closed-form representations for the resonant reaction rate are derived in terms of Meijer's G-function. Analytic representations of the resonant and nonresonant nuclear reaction rates are compared and the appearance of Meijer's G-function is discussed in physical terms

  5. Credit Rating and Competition

    OpenAIRE

    Nelson Camanho; Pragyan Deb; Zijun Liu

    2010-01-01

    In principle, credit rating agencies are supposed to be impartial observers that bridge the gap between private information of issuers and the information available to the wider pool of investors. However, since the 1970s, rating agencies have relied on an issuer-pay model, creating a conflict of interest the largest source of income for the rating agencies are the fees paid by the issuers the rating agencies are supposed to impartially rate. In this paper, we explore the trade-off between re...

  6. Understanding Interest Rate Volatility

    DEFF Research Database (Denmark)

    Volker, Desi

    This thesis is the result of my Ph.D. studies at the Department of Finance of the Copenhagen Business School. It consists of three essays covering topics related to the term structure of interest rates, monetary policy and interest rate volatility. The rst essay, \\Monetary Policy Uncertainty...... and Interest Rates", examines the role of monetary policy uncertainty on the term structure of interest rates. The second essay, \\A Regime-Switching A ne Term Structure Model with Stochastic Volatility" (co-authored with Sebastian Fux), investigates the ability of the class of regime switching models...... with and without stochastic volatility to capture the main stylized features of U.S. interest rates. The third essay, \\Variance Risk Premia in the Interest Rate Swap Market", investigates the time-series and cross-sectional properties of the compensation demanded for holding interest rate variance risk. The essays...

  7. Exchange rate policy

    Directory of Open Access Journals (Sweden)

    Plačkov Slađana

    2013-01-01

    Full Text Available Small oscillations of exchange rate certainly affect the loss of confidence in the currency (Serbian dinar, CSD and because of the shallow market even the smallest change in the supply and demand leads to a shift in exchange rate and brings uncertainty. Some economists suggest that the course should be linked to inflation and thus ensure predictable and stable exchange rates. Real exchange rate or slightly depressed exchange rate will encourage the competitiveness of exporters and perhaps ensure the development of new production lines which, in terms of overvalued exchange rate, had no economic justification. Fixed exchange rate will bring lower interest rates, lower risk and lower business uncertainty (uncertainty avoidance, but Serbia will also reduce foreign exchange reserves by following this trend. On the other hand, a completely free exchange rate, would lead to a (real fall of Serbian currency, which in a certain period would lead to a significant increase in exports, but the consequences for businessmen and citizens with loans pegged to the euro exchange rate, would be disastrous. We will pay special attention to the depreciation of the exchange rate, as it is generally favorable to the export competitiveness of Serbia and, on the other hand, it leads to an increase in debt servicing costs of the government as well as of the private sector. Oscillations of the dinar exchange rate, appreciation and depreciation, sometimes have disastrous consequences on the economy, investors, imports and exports. In subsequent work, we will observe the movement of the dinar exchange rate in Serbia, in the time interval 2009-2012, in order to strike a balance and maintain economic equilibrium. A movement of foreign currencies against the local currency is controlled in the foreign exchange market, so in case economic interests require, The National Bank of Serbia (NBS, on the basis of arbitrary criteria, can intervene in the market.

  8. Electric rate operations

    International Nuclear Information System (INIS)

    Maillard, D.

    1993-01-01

    The share of nuclear power in EDF production implies multiple rate structures. How are these rates determined. What are the new applications of electricity, and in particular those that make use of the especially low summer prices for electricity. These are topics of interest to the man in the street (witness EDF's recent 'red-white-blue' rates). This prompted the 'Nuclear Power in the Financial, Energy and Economic situation' department of France's nuclear power company to organize a conference bringing together an expert on rates - M.P. Bernard, head of the rate fixing service at the EDF's headquarters - and representatives from suppliers of equipment taking advantage of the various EDF rate options

  9. Observed Barium Emission Rates

    Science.gov (United States)

    Stenbaek-Nielsen, H. C.; Wescott, E. M.; Hallinan, T. J.

    1993-01-01

    The barium releases from the CRRES satellite have provided an opportunity for verifying theoretically calculated barium ion and neutral emission rates. Spectra of the five Caribbean releases in the summer of 1991 were taken with a spectrograph on board a U.S. Air Force jet aircraft. Because the line of sight release densities are not known, only relative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other observations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with photometric observations. It has been postulated that charge exchange between neutral barium and oxygen ions represents a significant source for ionization. If so. it should be associated with emissions at 4957.15 A and 5013.00 A, but these emissions were not detected.

  10. Understanding Rig Rates

    OpenAIRE

    Petter Osmundsen; Knut Einar Rosendahl; Terje Skjerpen

    2013-01-01

    We examine the largest cost component in offshore development projects, drilling rates, which have been high over the last years. To our knowledge, rig rates have not been analysed empirically before in the economic literature. By econometric analysis we examine the effects on Gulf of Mexico rig rates of gas and oil prices, rig capacity utilization, contract length and lead time, and rig specific characteristics. Having access to a unique data set containing contract information, we are able ...

  11. Airline Quality Rating 2013

    OpenAIRE

    Bowen, Brent D.; Headley, Dean E.

    2013-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method for assessing airline quality on combined multiple performance criteria. This current report, the Airline Quality Rating 2013, reflects monthly Airline Quality Rating scores for calendar year 2012. AQR scores for 2013 are based on 15 elements in four major areas that focus on airline performance aspects important to air travel consumers over the calendar year of 2012. The Airline Quality...

  12. Long Maturity Forward Rates

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2001-01-01

    The paper aims to improve the knowledge of the empirical properties of the long maturity region of the forward rate curve. Firstly, the theoretical negative correlation between the slope at the long end of the forward rate curve and the term structure variance is recovered empirically and found...... to be statistically significant. Secondly, the expectations hypothesis is analyzed for the long maturity region of the forward rate curve using "forward rate" regressions. The expectations hypothesis is numerically close to being accepted but is statistically rejected. The findings provide mixed support...... for the affine term structure model....

  13. Interest Rate Swaps

    Directory of Open Access Journals (Sweden)

    Marina Pepić

    2014-12-01

    Full Text Available Interest rates changes have a huge impact on the business performance. Therefore, it is of great importance for the market participants to identify and adequately manage this risk. Financial derivatives are a relatively simple way of protection from adverse changes in interest rates. Interest rate swaps are particularly popular because they reduce interest rate risk to a minimum with a relatively low initial cost and without great risk, but also because of the fact that there are manymodifications of the standard swap created to better satisfy the different needs of market players.

  14. Does basal metabolic rate drive eating rate?

    Science.gov (United States)

    Henry, Christiani Jeyakumar; Ponnalagu, Shalini; Bi, Xinyan; Forde, Ciaran

    2018-05-15

    There have been recent advances in our understanding of the drivers of energy intake (EI). However, the biological drivers of differences in eating rate (ER) remain less clear. Studies have reported that the fat-free mass (FFM) and basal metabolic rate (BMR) are both major components that contribute to daily energy expenditure (EE) and drive EI. More recently, a number of observations report that higher ER can lead to greater EI. The current study proposed that adults with a higher BMR and higher energy requirements would also exhibit higher ERs. Data on BMR, FFM, and ER were collected from 272 Chinese adults (91 males and 181 females) in a cross-sectional study. Analysis showed significant positive associations between BMR and ER (r s  = 0.405, p BMR explained about 15% of the variation in ER which was taken to be metabolically significant. This association provides metabolic explanation that the differences in an individual's BMR (hence energy requirements) may be correlated with ERs. This merits further research. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Rate of force development

    DEFF Research Database (Denmark)

    Maffiuletti, Nicola A; Aagaard, Per; Blazevich, Anthony J

    2016-01-01

    The evaluation of rate of force development during rapid contractions has recently become quite popular for characterising explosive strength of athletes, elderly individuals and patients. The main aims of this narrative review are to describe the neuromuscular determinants of rate of force devel...

  16. Extended rate equations

    International Nuclear Information System (INIS)

    Shore, B.W.

    1981-01-01

    The equations of motion are discussed which describe time dependent population flows in an N-level system, reviewing the relationship between incoherent (rate) equations, coherent (Schrodinger) equations, and more general partially coherent (Bloch) equations. Approximations are discussed which replace the elaborate Bloch equations by simpler rate equations whose coefficients incorporate long-time consequences of coherence

  17. Applications of Reaction Rate

    Science.gov (United States)

    Cunningham, Kevin

    2007-01-01

    This article presents an assignment in which students are to research and report on a chemical reaction whose increased or decreased rate is of practical importance. Specifically, students are asked to represent the reaction they have chosen with an acceptable chemical equation, identify a factor that influences its rate and explain how and why it…

  18. Rating mutual funds

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Rangvid, Jesper

    2007-01-01

    We develop a new rating of mutual funds: the atpRating. The atpRating assigns crowns to each individual mutual fund based upon the costs an investor pays when investing in the fund in relation to what it would cost to invest in the fund's peers. Within each investment category, the rating assigns...... the return of a fund in a certain year generally contains only little information about the future return that the fund will generate. Finally, we have information on the investments in different mutual funds made by a small subgroup of investors known to have been exposed to both the atp...... five crowns to funds with the lowest costs and one crown to funds with the highest costs. We investigate the ability of the atpRating to predict the future performance of a fund. We find that an investor who has invested in the funds with the lowest costs within an investment category would have...

  19. Rating Mutual Funds

    DEFF Research Database (Denmark)

    Bechmann, Ken L.; Rangvid, Jesper

    We develop a new rating of mutual funds: the atpRating. The atpRating assigns crowns to each individual mutual fund based upon the costs an investor pays when investing in the fund in relation to what it would cost to invest in the fund’s peers. Within each investment category, the rating assigns......, whereas the return of a fund in a certain year generally contains only little information about the future return that the fund will generate. Finally, we have information on the investments in different mutual funds made by a small subgroup of investors known to have been exposed to both the atp...... five crowns to funds with the lowest costs and one crown to funds with the highest costs. We investigate the ability of the atpRating to predict the future performance of a fund. We find that an investor who has invested in the funds with the lowest costs within an investment category would have...

  20. Interest rates mapping

    Science.gov (United States)

    Kanevski, M.; Maignan, M.; Pozdnoukhov, A.; Timonin, V.

    2008-06-01

    The present study deals with the analysis and mapping of Swiss franc interest rates. Interest rates depend on time and maturity, defining term structure of the interest rate curves (IRC). In the present study IRC are considered in a two-dimensional feature space-time and maturity. Exploratory data analysis includes a variety of tools widely used in econophysics and geostatistics. Geostatistical models and machine learning algorithms (multilayer perceptron and Support Vector Machines) were applied to produce interest rate maps. IR maps can be used for the visualisation and pattern perception purposes, to develop and to explore economical hypotheses, to produce dynamic asset-liability simulations and for financial risk assessments. The feasibility of an application of interest rates mapping approach for the IRC forecasting is considered as well.

  1. River rating complexity

    Science.gov (United States)

    Holmes, Robert R.

    2016-01-01

    Accuracy of streamflow data depends on the veracity of the rating model used to derive a continuous time series of discharge from the surrogate variables that can readily be collected autonomously at a streamgage. Ratings are typically represented as a simple monotonic increasing function (simple rating), meaning the discharge is a function of stage alone, however this is never truly the case unless the flow is completely uniform at all stages and in transitions from one stage to the next. For example, at some streamflow-monitoring sites the discharge on the rising limb of the hydrograph is discernably larger than the discharge at the same stage on the falling limb of the hydrograph. This is the so-called “loop rating curve” (loop rating). In many cases, these loops are quite small and variation between rising- and falling-limb discharge measurements made at the same stage are well within the accuracy of the measurements. However, certain hydraulic conditions can produce a loop that is large enough to preclude use of a monotonic rating. A detailed data campaign for the Mississippi River at St. Louis, Missouri during a multi-peaked flood over a 56-day period in 2015 demonstrates the rating complexity at this location. The shifting-control method used to deal with complexity at this site matched all measurements within 8%.

  2. Throughput rate study

    International Nuclear Information System (INIS)

    Ford, L.; Bailey, W.; Gottlieb, P.; Emami, F.; Fleming, M.; Robertson, D.

    1993-01-01

    The Civilian Radioactive Waste Management System (CRWMS) Management and Operating (M ampersand O) Contractor, has completed a study to analyze system wide impacts of operating the CRWMS at varying throughput rates, including the 3000 MTU/year rate which has been assumed in the past. Impacts of throughput rate on all phases of the CRWMS operations (acceptance, transportation, storage and disposal) were evaluated. The results of the study indicate that a range from 3000 to 5000 MTU/year is preferred, based on system cost per MTU of SNF emplaced and logistics constraints

  3. 76 FR 77581 - Interest Rates

    Science.gov (United States)

    2011-12-13

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  4. 77 FR 76586 - Interest Rates

    Science.gov (United States)

    2012-12-28

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  5. 76 FR 18821 - Interest Rates

    Science.gov (United States)

    2011-04-05

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  6. 78 FR 18664 - Interest Rates

    Science.gov (United States)

    2013-03-27

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  7. 75 FR 81326 - Interest Rates

    Science.gov (United States)

    2010-12-27

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  8. 77 FR 39560 - Interest Rates

    Science.gov (United States)

    2012-07-03

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  9. 75 FR 37872 - Interest Rates

    Science.gov (United States)

    2010-06-30

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  10. 77 FR 20476 - Interest Rates

    Science.gov (United States)

    2012-04-04

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  11. 75 FR 60152 - Interest Rates

    Science.gov (United States)

    2010-09-29

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  12. 77 FR 59447 - Interest Rates

    Science.gov (United States)

    2012-09-27

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  13. 78 FR 62932 - Interest Rates

    Science.gov (United States)

    2013-10-22

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  14. 78 FR 39434 - Interest Rates

    Science.gov (United States)

    2013-07-01

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This rate will...

  15. Allegheny County Obesity Rates

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Obesity rates for each Census Tract in Allegheny County were produced for the study “Developing small-area predictions for smoking and obesity prevalence in the...

  16. Lapse rate modeling

    DEFF Research Database (Denmark)

    De Giovanni, Domenico

    2010-01-01

    prepayment models for mortgage backed securities, this paper builds a Rational Expectation (RE) model describing the policyholders' behavior in lapsing the contract. A market model with stochastic interest rates is considered, and the pricing is carried out through numerical approximation...

  17. Lapse Rate Modeling

    DEFF Research Database (Denmark)

    De Giovanni, Domenico

    prepayment models for mortgage backed securities, this paper builds a Rational Expectation (RE) model describing the policyholders' behavior in lapsing the contract. A market model with stochastic interest rates is considered, and the pricing is carried out through numerical approximation...

  18. Resettlement and Birth Rates

    African Journals Online (AJOL)

    GB

    The Relationship between Resettlement and Birth Rates: The Case of ... statistical software. SAS is used. RESULTS: In a univariate analysis of Gambella's ..... World Bank Conference on Land And. Poverty. Washington DC, World Bank, April.

  19. Bridge element deterioration rates.

    Science.gov (United States)

    2008-10-01

    This report describes the development of bridge element deterioration rates using the NYSDOT : bridge inspection database using Markov chains and Weibull-based approaches. It is observed : that Weibull-based approach is more reliable for developing b...

  20. Allegheny County Smoking Rates

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Smoking rates for each Census Tract in Allegheny County were produced for the study “Developing small-area predictions for smoking and obesity prevalence in the...

  1. Interest Rates and Inflation

    OpenAIRE

    Coopersmith, Michael

    2011-01-01

    A relation between interest rates and inflation is presented using a two component economic model and a simple general principle. Preliminary results indicate a remarkable similarity to classical economic theories, in particular that of Wicksell.

  2. Fertility Clinic Success Rates

    Science.gov (United States)

    ... Defects ART and Autism 2013 Assisted Reproductive Technology Fertility Clinic Success Rates Report Recommend on Facebook Tweet ... Additional Information About ART in the United States. Fertility Clinic Tables Introduction to Fertility Clinic Tables [PDF - ...

  3. Debenture Interest Rates

    Data.gov (United States)

    Department of Housing and Urban Development — Interest rates to be paid on debentures issued with respect to a loan or mortgage insured by the Federal Housing Commissioner under the provisions of the National...

  4. Rate of Speed

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Rate of spread was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The tool...

  5. Rating Your Cash Manager?

    Science.gov (United States)

    Nielsen, George A.; Johannisson, Eric E.

    1989-01-01

    The primary objective of a public cash management policy should include safety, liquidity, yield, and legality. Contains a cash management policy/procedure checklist, a test for cash managers, and a formula for calculating the rate of return. (MLF)

  6. Ventilation rates and health

    DEFF Research Database (Denmark)

    Sundell, Jan; Levin, H; Nazaroff, W W

    2011-01-01

    and health effects to inform the relationship. Consistency was found across multiple investigations and different epidemiologic designs for different populations. Multiple health endpoints show similar relationships with ventilation rate. There is biological plausibility for an association of health outcomes...... studies of the relationship between ventilation rates and health, especially in diverse climates, in locations with polluted outdoor air and in buildings other than offices. PRACTICAL IMPLICATIONS: Ventilation with outdoor air plays an important role influencing human exposures to indoor pollutants...

  7. High population increase rates.

    Science.gov (United States)

    1991-09-01

    In addition to its economic and ethnic difficulties, the USSR faces several pressing demographic problems, including high population increase rates in several of its constituent republics. It has now become clear that although the country's rigid centralized planning succeeded in covering the basic needs of people, it did not lead to welfare growth. Since the 1970s, the Soviet economy has remained sluggish, which as led to increase in the death and birth rates. Furthermore, the ideology that held that demography could be entirely controlled by the country's political and economic system is contradicted by current Soviet reality, which shows that religion and ethnicity also play a significant role in demographic dynamics. Currently, Soviet republics fall under 2 categories--areas with high or low natural population increase rates. Republics with low rates consist of Christian populations (Armenia, Moldavia, Georgia, Byelorussia, Russia, Lithuania, Estonia, Latvia, Ukraine), while republics with high rates are Muslim (Tadzhikistan, Uzbekistan, Turkmenistan, Kirgizia, Azerbaijan Kazakhstan). The later group has natural increase rates as high as 3.3%. Although the USSR as a whole is not considered a developing country, the later group of republics fit the description of the UNFPA's priority list. Another serious demographic issue facing the USSR is its extremely high rate of abortion. This is especially true in the republics of low birth rates, where up to 60% of all pregnancies are terminated by induced abortions. Up to 1/5 of the USSR's annual health care budget is spent on clinical abortions -- money which could be better spent on the production of contraceptives. Along with the recent political and economic changes, the USSR is now eager to deal with its demographic problems.

  8. Floating Exchange Rate Regime

    OpenAIRE

    Quader, Syed Manzur

    2004-01-01

    In recent years, many developing countries having a history of high inflation, unfavorable balance of payment situation and a high level of foreign currencies denominated debt, have switched or are in the process of switching to a more flexible exchange rate regime. Therefore, the stability of the exchange rate and the dynamics of its volatility are more crucial than before to prevent financial crises and macroeconomic disturbances. This paper is designed to find out the reasons behind Bangla...

  9. Real exchange rate misalignments

    OpenAIRE

    Terra, Maria Cristina T.; Valladares, Frederico Estrella Carneiro

    2003-01-01

    This paper characterizes episodes of real appreciations and depreciations for a sample of 85 countries, approximately from 1960 to 1998. First, the equilibrium real exchange rate series are constructed for each country using Goldfajn and Valdes (1999) methodology (cointegration with fundamentals). Then, departures from equilibrium real exchange rate (misalignments) are obtained, and a Markov Switching Model is used to characterize the misalignments series as stochastic autor...

  10. Hydration rate of obsidian.

    Science.gov (United States)

    Friedman, I; Long, W

    1976-01-30

    The hydration rates of 12 obsidian samples of different chemical compositions were measured at temperatures from 95 degrees to 245 degrees C. An expression relating hydration rate to temperature was derived for each sample. The SiO(2) content and refractive index are related to the hydration rate, as are the CaO, MgO, and original water contents. With this information it is possible to calculate the hydration rate of a sample from its silica content, refractive index, or chemical index and a knowledge of the effective temperature at which the hydration occurred. The effective hydration temperature can be either measured or approximated from weather records. Rates have been calculated by both methods, and the results show that weather records can give a good approximation to the true EHT, particularly in tropical and subtropical climates. If one determines the EHT by any of the methods suggested, and also measures or knows the rate of hydration of the particular obsidian used, it should be possible to carry out absolute dating to +/- 10 percent of the true age over periods as short as several years and as long as millions of years.

  11. Ratings are Overrated!

    Directory of Open Access Journals (Sweden)

    Georgios N. Yannakakis

    2015-07-01

    Full Text Available Are ratings of any use in human-computer interaction and user studies at large? If ratings are of limited use, is there a better alternative for quantitative subjective assessment? Beyond the intrinsic shortcomings of human reporting, there are a number of supplementary limitations and fundamental methodological flaws associated with rating-based questionnaires --- i.e. questionnaires that ask participants to rate their level of agreement with a given statement such as a Likert item. While the effect of these pitfalls has been largely downplayed, recent findings from diverse areas of study question the reliability of using ratings. Rank-based questionnaires --- i.e. questionnaires that ask participants to rank two or more options --- appear as the evident alternative that not only eliminates the core limitations of ratings but also simplifies the use of sound methodologies that yield more reliable models of the underlying reported construct: user emotion, preference, or opinion. This paper solicits recent findings from various disciplines interlinked with psychometrics and offers a quick guide for the use, processing and analysis of rank-based questionnaires for the unique advantages they offer. The paper challenges the traditional state-of-practice in human-computer interaction and psychometrics directly contributing towards a paradigm shift in subjective reporting.

  12. 75 FR 17453 - Interest Rates

    Science.gov (United States)

    2010-04-06

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may [[Page 17454

  13. Predicting Agency Rating Migrations with Spread Implied Ratings

    OpenAIRE

    Jianming Kou; Dr Simone Varotto

    2005-01-01

    Investors traditionally rely on credit ratings to price debt instruments. However, rating agencies are known to be prudent in their approach to rating revisions, which results in delayed ratings adjustments to mutating credit conditions. For a large set of eurobonds we derive credit spread implied ratings and compare them with the ratings issued by rating agencies. Our results indicate that spread implied ratings often anticipate future movement of agency ratings and hence could help track cr...

  14. Asteroid rotation rates

    International Nuclear Information System (INIS)

    Binzel, R.P.; Farinella, P.

    1989-01-01

    Within the last decade the data base of asteroid rotation parameters (rotation rates and lightcurve amplitudes) has become sufficiently large to identify some definite rends and properties which can help us to interpret asteroid collisional evolution. Many significant correlations are found between rotation parameters and diameter, with distinct changes occurring near 125 km. The size range, which is also the diameter above which self-gravity may become important, perhaps represents a division between surviving primordial asteroids and collisional fragments. A Maxwellian is able to fit the observed rotation rate distributions of asteroids with D>125 km, implying that their rotation rates may be determined by collisional evolution. Asteroids with D<125 km show an excess of slow rotators and their non-Maxwellian distributions suggests that their rotation rates are more strongly influenced by other processes, such as the distribution resulting from their formation in catastrophic disruption events. Other correlations observed in the data set include different mean rotation rates for C, S and M type asteroids implying that their surface spectra are indicative of bulk properties

  15. Calculating graduation rates.

    Science.gov (United States)

    Starck, Patricia L; Love, Karen; McPherson, Robert

    2008-01-01

    In recent years, the focus has been on increasing the number of registered nurse (RN) graduates. Numerous states have initiated programs to increase the number and quality of students entering nursing programs, and to expand the capacity of their programs to enroll additional qualified students. However, little attention has been focused on an equally, if not more, effective method for increasing the number of RNs produced-increasing the graduation rate of students enrolling. This article describes a project that undertook the task of compiling graduation data for 15 entry-level programs, standardizing terms and calculations for compiling the data, and producing a regional report on graduation rates of RN students overall and by type of program. Methodology is outlined in this article. This effort produced results that were surprising to program deans and directors and is expected to produce greater collaborative efforts to improve these rates both locally and statewide.

  16. Rate based failure detection

    Science.gov (United States)

    Johnson, Brett Emery Trabun; Gamage, Thoshitha Thanushka; Bakken, David Edward

    2018-01-02

    This disclosure describes, in part, a system management component and failure detection component for use in a power grid data network to identify anomalies within the network and systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription. The failure detection component may identify an anomaly within the network and a source of the anomaly. Based on the identified anomaly, data rates and or data paths may be adjusted in real-time to ensure that the power grid data network does not become overloaded and/or fail.

  17. Homicide Rates in Lithuania.

    Science.gov (United States)

    Chmieliauskas, Sigitas; Laima, Sigitas; Andriuskeviciute, Gerda; Jurolaic, Eleonora; Jasulaitis, Algimantas

    2018-05-01

    Homicide rate in Lithuania between 2004 and 2013 decreased and reached an average of 6.7 per 100,000 people in 2013. The data regarding forensic autopsies of intentional homicide victims were obtained from the State Forensic Medicine Service. Spearman's correlation test was used to assess trends in the homicide rates. A significant correlation was observed between homicide distribution and the following variables: Lithuania's gross domestic product (r = -0.85, p = 0.003), the number of alcohol intoxication cases of victims (r = 0.97, p homicide distribution (p homicides were carried out indoors, 57% in urban area. The presented findings help decide which prevention programs may be the most effective in homicide rate reduction. © 2017 American Academy of Forensic Sciences.

  18. 76 FR 38717 - Interest Rates

    Science.gov (United States)

    2011-07-01

    ... SMALL BUSINESS ADMINISTRATION Interest Rates The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120.214) on a quarterly basis. This rate is a.... This rate may be used as a base rate for guaranteed fluctuating interest rate SBA loans. This [[Page...

  19. Estimating Discount Rates

    Directory of Open Access Journals (Sweden)

    Laurence Booth

    2015-04-01

    Full Text Available Discount rates are essential to applied finance, especially in setting prices for regulated utilities and valuing the liabilities of insurance companies and defined benefit pension plans. This paper reviews the basic building blocks for estimating discount rates. It also examines market risk premiums, as well as what constitutes a benchmark fair or required rate of return, in the aftermath of the financial crisis and the U.S. Federal Reserve’s bond-buying program. Some of the results are disconcerting. In Canada, utilities and pension regulators responded to the crash in different ways. Utilities regulators haven’t passed on the full impact of low interest rates, so that consumers face higher prices than they should whereas pension regulators have done the opposite, and forced some contributors to pay more. In both cases this is opposite to the desired effect of monetary policy which is to stimulate aggregate demand. A comprehensive survey of global finance professionals carried out last year provides some clues as to where adjustments are needed. In the U.S., the average equity market required return was estimated at 8.0 per cent; Canada’s is 7.40 per cent, due to the lower market risk premium and the lower risk-free rate. This paper adds a wealth of historic and survey data to conclude that the ideal base long-term interest rate used in risk premium models should be 4.0 per cent, producing an overall expected market return of 9-10.0 per cent. The same data indicate that allowed returns to utilities are currently too high, while the use of current bond yields in solvency valuations of pension plans and life insurers is unhelpful unless there is a realistic expectation that the plans will soon be terminated.

  20. Rates of star formation

    International Nuclear Information System (INIS)

    Larson, R.B.

    1977-01-01

    It is illustrated that a theoretical understanding of the formation and evolution of galaxies depends on an understanding of star formation, and especially of the factors influencing the rate of star formation. Some of the theoretical problems of star formation in galaxies, some approaches that have been considered in models of galaxy evolution, and some possible observational tests that may help to clarify which processes or models are most relevant are reviewed. The material is presented under the following headings: power-law models for star formation, star formation processes (conditions required, ways of achieving these conditions), observational indications and tests, and measures of star formation rates in galaxies. 49 references

  1. Estimating NHL Scoring Rates

    OpenAIRE

    Buttrey, Samuel E.; Washburn, Alan R.; Price, Wilson L.; Operations Research

    2011-01-01

    The article of record as published may be located at http://dx.doi.org/10.2202/1559-0410.1334 We propose a model to estimate the rates at which NHL teams score and yield goals. In the model, goals occur as if from a Poisson process whose rate depends on the two teams playing, the home-ice advantage, and the manpower (power-play, short-handed) situation. Data on all the games from the 2008-2009 season was downloaded and processed into a form suitable for the analysis. The model...

  2. Weak interaction rates

    International Nuclear Information System (INIS)

    Sugarbaker, E.

    1995-01-01

    I review available techniques for extraction of weak interaction rates in nuclei. The case for using hadron charge exchange reactions to estimate such rates is presented and contrasted with alternate methods. Limitations of the (p,n) reaction as a probe of Gamow-Teller strength are considered. Review of recent comparisons between beta-decay studies and (p,n) is made, leading to cautious optimism regarding the final usefulness of (p,n)- derived GT strengths to the field of astrophysics. copyright 1995 American Institute of Physics

  3. Weather Balloon Ascent Rate

    Science.gov (United States)

    Denny, Mark

    2016-05-01

    The physics of a weather balloon is analyzed. The surprising aspect of the motion of these balloons is that they ascend to great altitudes (typically 35 km) at a more or less constant rate. Such behavior is not surprising near the ground—say for a helium-filled party balloon rising from street level to the top of the Empire State building—but it is unexpected for a balloon that rises to altitudes where the air is rarefied. We show from elementary physical laws why the ascent rate is approximately constant.

  4. Basic Exchange Rate Theories

    NARCIS (Netherlands)

    J.G.M. van Marrewijk (Charles)

    2005-01-01

    textabstractThis four-chapter overview of basic exchange rate theories discusses (i) the elasticity and absorption approach, (ii) the (long-run) implications of the monetary approach, (iii) the short-run effects of monetary and fiscal policy under various economic conditions, and (iv) the transition

  5. Openings for Zero Rating

    NARCIS (Netherlands)

    A. Preta (Augusto); P. Peng (Peng)

    2016-01-01

    textabstractZero rating (toll-free data) is the practice of internet service providers (ISPs) and mobile operators not charging end users for data usage of specific internet content and applications of content providers through their network. On one hand it may benefit consumers from using the

  6. Rating of environmental criteria

    Energy Technology Data Exchange (ETDEWEB)

    Glueck, K; Krasser, G

    1980-01-01

    After a general theoretical discussion on the question of rating within a framework of cost-benefit studies, first trials as to the quantification and standardisation of twelve selected environmental criteria by means of an indicator system are worked out and compiled. The selection includes the criteria exhaust gas, dust, micro climate, water pollution, water regime, land requirement, vibrations, traffic noise, landscape scene, urban scene, effect of separation and safety risks. An insight is given of the rating practice using an evaluation of the available literature, of a household interview and of an interview of experts. The interviewing of 156 experts as to their rating conception of ten criteria in the second round has provided contributions to the general problem of the evaluation estimate based on multi criteria analysis as well as differentiation of the twelve or ten environmental criteria. The following criteria ratings given by the experts and which are averaged and smoothed are: traffic noise 20,0% +- 8,5; air pollution 15,0% +- 7,0; safety risk 13,0% +- 7,0; soil and water pollution 8,5% +- 5,0; landscape scene 8,0% +- 4,5; urban scene 8,0% +- 4,5; water regime 6,5% +- 3,5 and vibrations 4,5% +- 2,5.

  7. NUTRITIONAL AND HORMONAL FACTORS AFFECTING FRUIT SET IN AVOCADO (Persea americana Mill.)

    OpenAIRE

    D'ASARO, ANTONIO

    2017-01-01

    Under favourable conditions, the avocado sets more fruits than the tree is able to bring to maturity, so that the plant adjusts, during the early stages of development, its ability to nourish them by modifying their number, that is, causing the fruit drop of those who can not maintain their growth rate. Accordingly, carbohydrate availability could be a key factor in the physiological abscission of these fruits. Since this species presents dichogamy, the abscission of fruits has also been attr...

  8. Unusual ISS Rate Signature

    Science.gov (United States)

    Laible, Michael R.

    2011-01-01

    On November 23, 2011 International Space Station Guidance, Navigation, and Control reported unusual pitch rate disturbance. These disturbances were an order of magnitude greater than nominal rates. The Loads and Dynamics team was asked to review and analyze current accelerometer data to investigate this disturbance. This paper will cover the investigation process under taken by the Loads and Dynamics group. It will detail the accelerometers used and analysis performed. The analysis included performing Frequency Fourier Transform of the data to identify the mode of interest. This frequency data is then reviewed with modal analysis of the ISS system model. Once this analysis is complete and the disturbance quantified, a forcing function was produced to replicate the disturbance. This allows the Loads and Dynamics team to report the load limit values for the 100's of interfaces on the ISS.

  9. Time, rate, and conditioning.

    Science.gov (United States)

    Gallistel, C R; Gibbon, J

    2000-04-01

    The authors draw together and develop previous timing models for a broad range of conditioning phenomena to reveal their common conceptual foundations: First, conditioning depends on the learning of the temporal intervals between events and the reciprocals of these intervals, the rates of event occurrence. Second, remembered intervals and rates translate into observed behavior through decision processes whose structure is adapted to noise in the decision variables. The noise and the uncertainties consequent on it have both subjective and objective origins. A third feature of these models is their timescale invariance, which the authors argue is a very important property evident in the available experimental data. This conceptual framework is similar to the psychophysical conceptual framework in which contemporary models of sensory processing are rooted. The authors contrast it with the associative conceptual framework.

  10. Radiation dose rate meter

    International Nuclear Information System (INIS)

    Kronenberg, S.; Siebentritt, C.R.

    1981-01-01

    A combined dose rate meter and charger unit therefor which does not require the use of batteries but on the other hand produces a charging potential by means of a piezoelectric cylinder which is struck by a manually triggered hammer mechanism. A tubular type electrometer is mounted in a portable housing which additionally includes a geiger-muller (Gm) counter tube and electronic circuitry coupled to the electrometer for providing multi-mode operation. In one mode of operation, an rc circuit of predetermined time constant is connected to a storage capacitor which serves as a timed power source for the gm tube, providing a measurement in terms of dose rate which is indicated by the electrometer. In another mode, the electrometer indicates individual counts

  11. On multiple discount rates

    OpenAIRE

    Chambers, Christopher P.; Echenique, Federico

    2016-01-01

    We propose a theory of intertemporal choice that is robust to specific assumptions on the discount rate. One class of models requires that one utility stream be chosen over another if and only if its discounted value is higher for all discount factors in a set. Another model focuses on an average discount factor. Yet another model is pessimistic, and evaluates a flow by the lowest available discounted value.

  12. VAP rates unchanged

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2016-12-01

    Full Text Available No abstract available. Article truncated at 150 words. In a research letter to JAMA Metersky and colleagues (1 report that ventilator-associated pneumonia (VAP rates have remained near 10% since 2005. The authors reviewed Medicare Patient Safety Monitoring System (MPSMS data on a representative sample of more than 86,000 critically ill patients treated at 1330 US hospitals between 2005 and 2013. To meet a diagnosis of VAP patients were required to have at least 2 days' ventilation in intensive care units; a chest radiograph with a new finding suggesting pneumonia; a physician diagnosis of pneumonia; and an order for antibiotics. VAP incidence was 10.8% (95% confidence interval, 7.4% - 14.4% during 2005 to 2006 and 9.7% (95% confidence interval, 5.1% - 14.9% during 2012 to 2013. In contrast, data from the CDC's National Healthcare Safety Network (NHSN have shown declines in VAP rates of 71% and 62% in medical and surgical intensive care units, respectively, between 2006 and 2012 …

  13. Neonatal heart rate prediction.

    Science.gov (United States)

    Abdel-Rahman, Yumna; Jeremic, Aleksander; Tan, Kenneth

    2009-01-01

    Technological advances have caused a decrease in the number of infant deaths. Pre-term infants now have a substantially increased chance of survival. One of the mechanisms that is vital to saving the lives of these infants is continuous monitoring and early diagnosis. With continuous monitoring huge amounts of data are collected with so much information embedded in them. By using statistical analysis this information can be extracted and used to aid diagnosis and to understand development. In this study we have a large dataset containing over 180 pre-term infants whose heart rates were recorded over the length of their stay in the Neonatal Intensive Care Unit (NICU). We test two types of models, empirical bayesian and autoregressive moving average. We then attempt to predict future values. The autoregressive moving average model showed better results but required more computation.

  14. Money market rates and implied CCAPM rates: some international evidence

    OpenAIRE

    Yamin Ahmad

    2004-01-01

    New Neoclassical Synthesis models equate the instrument of monetary policy to the implied CCAPM rate arising from an Euler equation. This paper identifies monetary policy shocks within six of the G7 countries and examines the movement of money market and implied CCAPM rates. The key result is that an increase in the nominal interest rate leads to a fall in the implied CCAPM rate. Incorporating habit still yields the same result. The findings suggest that the movement of these two rates implie...

  15. 29 CFR 778.112 - Day rates and job rates.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Day rates and job rates. 778.112 Section 778.112 Labor... Requirements Principles for Computing Overtime Pay Based on the âregular Rateâ § 778.112 Day rates and job rates. If the employee is paid a flat sum for a day's work or for doing a particular job, without regard...

  16. Various rates of k and Na influence growth, seed cotton yield and ionic ratio of two cotton varieties in soil culture

    International Nuclear Information System (INIS)

    Ali, L.; Maqsood, M.A.; Ashraf, M.

    2009-01-01

    Cotton is generally grown on alkaline calcareous soils in arid and semi-arid areas of the country. Sodium can interact with other earth cations like K, Ca and Mg. Therefore, a pot study was conducted to investigate the growth, yield and ionic response of two cotton varieties. Four levels of K and Na were developed after considering indigenous K, Na status in soil. The treatments of K+Na in mg/kg were adjusted as, 105+37.5, 135+30 135+37.5 and 105+30 (control). Control treatment represented indigenous K, Na status of soil. The experiment continued until maturity. Application of K and Na increased seed cotton yield and boll weight significantly (p<0.01). Both varieties varied non-significantly with respect to K:Na ratio in leaf. The beneficial effects of Na with K application over control on seed cotton yield and boll weight were greater in NIBGE-2 than in MNH-786. Increase in seed cotton yield was attributed to maximum boll weight of both varieties. Significant negative correlation (r= -0.89, - 0.76, n= 4) was found between K:Na ratio and K use efficiency in shoot of NIBGE-2 and MNH-786, respectively. (author)

  17. Credit rating dynamics and competition

    DEFF Research Database (Denmark)

    Hirth, Stefan

    2014-01-01

    I analyze the market for credit ratings with competition between more than two rating agencies. How can honest rating behavior be achieved, and under which conditions can a new honest rating agency successfully invade a market with inflating incumbents? My model predicts cyclic dynamics...

  18. Decomposing the social discount rate

    OpenAIRE

    Scarborough, Helen

    2010-01-01

    Recent modelling of the costs and benefits of climate change has renewed debate surrounding assumptions regarding the social discount rate in analysing the impacts of environmental change. Previous literature segments the social discount rate into being influenced by two key factors; the rate of pure time preference and the elasticity of marginal utility of future consumption. These components of the social discount rate reinforce the linkages between the choice of social discount rate and in...

  19. Exchange rate smoothing in Hungary

    OpenAIRE

    Karádi, Péter

    2005-01-01

    The paper proposes a structural empirical model capable of examining exchange rate smoothing in the small, open economy of Hungary. The framework assumes the existence of an unobserved and changing implicit exchange rate target. The central bank is assumed to use interest rate policy to obtain this preferred rate in the medium term, while market participants are assumed to form rational expectations about this target and influence exchange rates accordingly. The paper applies unobserved varia...

  20. Estimating diversification rates for higher taxa: BAMM can give problematic estimates of rates and rate shifts.

    Science.gov (United States)

    Meyer, Andreas L S; Wiens, John J

    2018-01-01

    Estimates of diversification rates are invaluable for many macroevolutionary studies. Recently, an approach called BAMM (Bayesian Analysis of Macro-evolutionary Mixtures) has become widely used for estimating diversification rates and rate shifts. At the same time, several articles have concluded that estimates of net diversification rates from the method-of-moments (MS) estimators are inaccurate. Yet, no studies have compared the ability of these two methods to accurately estimate clade diversification rates. Here, we use simulations to compare their performance. We found that BAMM yielded relatively weak relationships between true and estimated diversification rates. This occurred because BAMM underestimated the number of rates shifts across each tree, and assigned high rates to small clades with low rates. Errors in both speciation and extinction rates contributed to these errors, showing that using BAMM to estimate only speciation rates is also problematic. In contrast, the MS estimators (particularly using stem group ages), yielded stronger relationships between true and estimated diversification rates, by roughly twofold. Furthermore, the MS approach remained relatively accurate when diversification rates were heterogeneous within clades, despite the widespread assumption that it requires constant rates within clades. Overall, we caution that BAMM may be problematic for estimating diversification rates and rate shifts. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  1. National Utility Rate Database: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Ong, S.; McKeel, R.

    2012-08-01

    When modeling solar energy technologies and other distributed energy systems, using high-quality expansive electricity rates is essential. The National Renewable Energy Laboratory (NREL) developed a utility rate platform for entering, storing, updating, and accessing a large collection of utility rates from around the United States. This utility rate platform lives on the Open Energy Information (OpenEI) website, OpenEI.org, allowing the data to be programmatically accessed from a web browser, using an application programming interface (API). The semantic-based utility rate platform currently has record of 1,885 utility rates and covers over 85% of the electricity consumption in the United States.

  2. The influence of sovereign credit ratings on corporate credit ratings.

    OpenAIRE

    Umutoni, Liliane

    2017-01-01

    Credit ratings have a key role in modern financial markets as they communicate crucial information on the creditworthiness of a debt issuer to investors and regulators. These credit ratings are mostly determined by three rating agencies, namely Standard & Poor’s, Moody’s and Fitch, even though, the credit rating industry counts a dozen of recognized rating agencies. Indeed, the three agencies have become the market leaders with a market share of 94.3% on the U.S market (Bloomberg, 2015) and 9...

  3. Content and ratings of mature-rated video games.

    Science.gov (United States)

    Thompson, Kimberly M; Tepichin, Karen; Haninger, Kevin

    2006-04-01

    To quantify the depiction of violence, blood, sexual themes, profanity, substances, and gambling in video games rated M (for "mature") and to measure agreement between the content observed and the rating information provided to consumers on the game box by the Entertainment Software Rating Board. We created a database of M-rated video game titles, selected a random sample, recorded at least 1 hour of game play, quantitatively assessed the content, performed statistical analyses to describe the content, and compared our observations with the Entertainment Software Rating Board content descriptors and results of our prior studies. Harvard University, Boston, Mass. Authors and 1 hired game player. M-rated video games. Percentages of game play depicting violence, blood, sexual themes, gambling, alcohol, tobacco, or other drugs; use of profanity in dialogue, song lyrics, or gestures. Although the Entertainment Software Rating Board content descriptors for violence and blood provide a good indication of such content in the game, we identified 45 observations of content that could warrant a content descriptor in 29 games (81%) that lacked these content descriptors. M-rated video games are significantly more likely to contain blood, profanity, and substances; depict more severe injuries to human and nonhuman characters; and have a higher rate of human deaths than video games rated T (for "teen"). Parents and physicians should recognize that popular M-rated video games contain a wide range of unlabeled content and may expose children and adolescents to messages that may negatively influence their perceptions, attitudes, and behaviors.

  4. 2007 Wholesale Power Rate Schedules : 2007 General Rate Schedule Provisions.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2006-11-01

    This schedule is available for the contract purchase of Firm Power to be used within the Pacific Northwest (PNW). Priority Firm (PF) Power may be purchased by public bodies, cooperatives, and Federal agencies for resale to ultimate consumers, for direct consumption, and for Construction, Test and Start-Up, and Station Service. Rates in this schedule are in effect beginning October 1, 2006, and apply to purchases under requirements Firm Power sales contracts for a three-year period. The Slice Product is only available for public bodies and cooperatives who have signed Slice contracts for the FY 2002-2011 period. Utilities participating in the Residential Exchange Program (REP) under Section 5(c) of the Northwest Power Act may purchase Priority Firm Power pursuant to the Residential Exchange Program. Rates under contracts that contain charges that escalate based on BPA's Priority Firm Power rates shall be based on the three-year rates listed in this rate schedule in addition to applicable transmission charges. This rate schedule supersedes the PF-02 rate schedule, which went into effect October 1, 2001. Sales under the PF-07 rate schedule are subject to BPA's 2007 General Rate Schedule Provisions (2007 GRSPs). Products available under this rate schedule are defined in the 2007 GRSPs. For sales under this rate schedule, bills shall be rendered and payments due pursuant to BPA's 2007 GRSPs and billing process.

  5. Breast Cancer Rates by State

    Science.gov (United States)

    ... Associated Lung Ovarian Prostate Skin Uterine Cancer Home Breast Cancer Rates by State Language: English (US) Español (Spanish) ... from breast cancer each year. Rates of Getting Breast Cancer by State The number of people who get ...

  6. 76 FR 7879 - Fee Rate

    Science.gov (United States)

    2011-02-11

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted preliminary annual fee rates of 0.00% for tier 1 and 0.074% (.00074) for tier 2 for... part 518, the preliminary fee rate on class II revenues for calendar year 2011 shall be one-half of the...

  7. 78 FR 14821 - Fee Rate

    Science.gov (United States)

    2013-03-07

    ... DEPARTMENT OF THE INTERIOR National Indian Gaming Commission Fee Rate AGENCY: National Indian..., that the National Indian Gaming Commission has adopted its 2013 preliminary annual fee rates of 0.00... self-regulation under 25 CFR part 518, the 2013 preliminary fee rate on Class II revenues shall be one...

  8. 75 FR 5342 - Fee Rate

    Science.gov (United States)

    2010-02-02

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted preliminary annual fee rates of 0.00% for tier 1 and 0.060% (.00060) for tier 2 for... part 518, the preliminary fee rate on class II revenues for calendar year 2010 shall be one-half of the...

  9. 77 FR 5267 - Fee Rate

    Science.gov (United States)

    2012-02-02

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted preliminary annual fee rates of 0.00% for tier 1 and 0.074% (.00074) for tier 2 for... part 518, the preliminary fee rate on class II revenues for calendar year 2012 shall be one-half of the...

  10. 75 FR 44807 - Fee Rate

    Science.gov (United States)

    2010-07-29

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted final annual fee rates of 0.00% for tier 1 and 0.060% (.00060) for tier 2 for calendar... 518, the preliminary fee rate on class II revenues for calendar year 2010 shall be one-half of the...

  11. 76 FR 38207 - Fee Rate

    Science.gov (United States)

    2011-06-29

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted final annual fee rates of 0.00% for tier 1 and 0.074% (.00074) for tier 2 for calendar... 518, the final fee rate on class II revenues for calendar year 2011 shall be one-half of the annual...

  12. 77 FR 41202 - Fee Rate

    Science.gov (United States)

    2012-07-12

    ... NATIONAL INDIAN GAMING COMMISSION Fee Rate AGENCY: National Indian Gaming Commission. ACTION... Commission has adopted final annual fee rates of 0.00% for tier 1 and 0.074% (.00074) for tier 2 for calendar... 518, the final fee rate on class II revenues for calendar year 2012 shall be one-half of the annual...

  13. Heart rate monitoring mobile applications

    OpenAIRE

    Chaudhry, Beenish M.

    2016-01-01

    Total number of times a heart beats in a minute is known as the heart rate. Traditionally, heart rate was measured using clunky gadgets but these days it can be measured with a smartphone?s camera. This can help you measure your heart rate anywhere and at anytime, especially during workouts so you can adjust your workout intensity to achieve maximum health benefits. With simple and easy to use mobile app, ?Unique Heart Rate Monitor?, you can also maintain your heart rate history for personal ...

  14. Heart rate monitoring mobile applications.

    Science.gov (United States)

    Chaudhry, Beenish M

    2016-01-01

    Total number of times a heart beats in a minute is known as the heart rate. Traditionally, heart rate was measured using clunky gadgets but these days it can be measured with a smartphone's camera. This can help you measure your heart rate anywhere and at anytime, especially during workouts so you can adjust your workout intensity to achieve maximum health benefits. With simple and easy to use mobile app, 'Unique Heart Rate Monitor', you can also maintain your heart rate history for personal reflection and sharing with a provider.

  15. Legal issues of tax rates

    OpenAIRE

    Sadílek, Jiří

    2010-01-01

    Tax rate problems The subject of the graduation thesis is legal problems of tax rate. The aim of this thesis is description and estimation of the flat tax rate and states, where is established. First of all I define the basic kinds of tax systems - the tax system with one tax rate, the progressive tax system and the flat tax system. Further I deal with the principles and elements of the flat tax rate as interpreted by American economists Robert E. Hall and Alvin Rabushka who are generally ack...

  16. Aggregate Social Discount Rate Derived from Individual Discount Rates

    OpenAIRE

    Kenneth F. Reinschmidt

    2002-01-01

    In the economic evaluation of large public-sector projects, an aggregate social discount rate may be used in present worth comparison of alternatives. This paper uses the assumptions that individual discount rates are constant over time and approximately Normally distributed across the affected population, with mean \\mu and variance \\sigma 2 , to derive an aggregate discount function that is exponential in form but with time-dependent aggregate discount rate \\rho (t) = \\mu - \\sigma 2 t/2, whe...

  17. Female literacy rate is a better predictor of birth rate and infant mortality rate in India

    Directory of Open Access Journals (Sweden)

    Suman Saurabh

    2013-01-01

    Full Text Available Background: Educated women are known to take informed reproductive and healthcare decisions. These result in population stabilization and better infant care reflected by lower birth rates and infant mortality rates (IMRs, respectively. Materials and Methods: Our objective was to study the relationship of male and female literacy rates with crude birth rates (CBRs and IMRs of the states and union territories (UTs of India. The data were analyzed using linear regression. CBR and IMR were taken as the dependent variables; while the overall literacy rates, male, and female literacy rates were the independent variables. Results: CBRs were inversely related to literacy rates (slope parameter = -0.402, P < 0.001. On multiple linear regression with male and female literacy rates, a significant inverse relationship emerged between female literacy rate and CBR (slope = -0.363, P < 0.001, while male literacy rate was not significantly related to CBR (P = 0.674. IMR of the states were also inversely related to their literacy rates (slope = -1.254, P < 0.001. Multiple linear regression revealed a significant inverse relationship between IMR and female literacy (slope = -0.816, P = 0.031, whereas male literacy rate was not significantly related (P = 0.630. Conclusion: Female literacy is relatively highly important for both population stabilization and better infant health.

  18. Understanding High Rate Behavior Through Low Rate Analog

    Science.gov (United States)

    2014-04-28

    challenges in high rate character- isation of polymers. The most important is that, owing to their low stress wavespeed, the structural response of...box’ tool, to provide supporting date for the rate dependent mechanical character- isation . Experiments were performed on a TA instruments Q800

  19. 15 CFR 700.3 - Priority ratings and rated orders.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Priority ratings and rated orders. 700.3 Section 700.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE NATIONAL SECURITY INDUSTRIAL BASE...

  20. Effects of Liraglutide on Heart Rate and Heart Rate Variability

    DEFF Research Database (Denmark)

    Kumarathurai, Preman; Anholm, Christian; Larsen, Bjørn Strøier

    2017-01-01

    OBJECTIVE: Reduced heart rate variability (HRV) and increased heart rate (HR) have been associated with cardiovascular mortality. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) increase HR, and studies have suggested that they may reduce HRV. We examined the effect of the GLP-1 RA...

  1. Rate My Stake: Interpretation of Ordinal Stake Ratings

    Science.gov (United States)

    Patricia Lebow; Grant Kirker

    2014-01-01

    Ordinal rating systems are commonly employed to evaluate biodeterioration of wood exposed outdoors over long periods of time. The purpose of these ratings is to compare the durability of test systems to nondurable wood products or known durable wood products. There are many reasons why these systems have evolved as the chosen method of evaluation, including having an...

  2. The foreign exchange rate rate exposure of nations

    OpenAIRE

    Entorf, Horst; Moebert, Jochen; Sonderhof, Katja

    2007-01-01

    Following the well-known approach by Adler and Dumas (1984) we evaluate the foreign exchange rate exposure of nations. Results based on data from 27 countries show that national foreign exchange rate exposures are significantly related to the current trade balance variables of corresponding economies.

  3. The optimal rating philosophy for the rating of SMEs

    NARCIS (Netherlands)

    Rikkers, F.; Thibeault, A.

    2007-01-01

    The objective of this research is to determine the optimal rating philosophy for the rating of SMEs, and to describe the consequences of the chosen philosophy on several related aspects. As to our knowledge, this is the first paper that studies the considerations of financial institutions on what

  4. BANK RATING. A COMPARATIVE ANALYSIS

    Directory of Open Access Journals (Sweden)

    Batrancea Ioan

    2015-07-01

    Full Text Available Banks in Romania offers its customers a wide range of products but which involves both risk taking. Therefore researchers seek to build rating models to help managers of banks to risk of non-recovery of loans and interest. In the following we highlight rating Raiffeisen Bank, BCR-ERSTE Bank and Transilvania Bank, based on the models CAAMPL and Stickney making a comparative analysis of the two rating models.

  5. Can Exchange Rates Be Predicted?

    OpenAIRE

    Siriwutiset, Trin

    2007-01-01

    Foreign exchange rates produce significant impacts on both the macroeconomic and microeconomic scale. Countries� government and multinational companies have been seeking ways to stabilize the exchange rates for a few decades. However, there is no perfect consensus on methods to control and stabilize the exchange rates. In fact, there are several occasions in history where turbulence movements caused crisis in the economies. There are several factors that are identified by economis...

  6. Management of interest rate risk

    Directory of Open Access Journals (Sweden)

    Šabović Šerif

    2014-01-01

    Full Text Available Interest rate risk is one of the biggest and most dangerous risks that a bank is exposed to. When a change of interest rates occurs, the incomes of a bank based on credits and securities endure significant changes. Banks resources also endure some changes. The change of interest rates changes the value of the assets and liabilities of the bank and it's net and investment worth . The change of interest rates also affects bank's balance sheet, income sheet statement and bank's share capital.

  7. Spontaneous mutation rates and the rate-doubling dose

    International Nuclear Information System (INIS)

    Von Borstel, R.C.; Moustaccki, E.; Latarjet, R.

    1978-01-01

    The amount of radiation required to double the frequency of mutations or tumours over the rate of those that occur spontaneously is called the rate-doubling dose. An equivalent concept has been proposed for exposure to other environmental mutagens. The doubling dose concept is predicated on the assumption that all human populations have the same spontaneous mutation rate, and that this spontaneous mutation rate is known. It is now established for prokaryotes and lower eukaryotes that numerous genes control the spontaneous mutation rate, and it is likely that the same is true for human cells as well. Given that the accepted mode of evolution of human populatons is from small, isolated groups of individuals, it seems likely that each population would have a different spontaneous mutation rate. Given that a minimum of twenty genes control or affect the spontaneous mutation rate, and that each of these in turn is susceptible to spontaneously arising or environmentally induced mutations, it seems likely that every individual within a population (except for siblings from identical multiple births) will have a unique spontaneous mutation rate. If each individual in a population does have a different spontaneous mutation rate, the doubling dose concept, in rigorous terms, is fallacious. Therefore, as with other concepts of risk evaluation, the doubling dose concept is subject to criticism. Nevertheless, until we know individual spontaneous mutation rates with precision, and can evaluate risks based on this information, the doubling dose concept has a heuristic value and is needed for practical assessment of risks for defined populations. (author)

  8. Failure Rates in Introductory Programming

    DEFF Research Database (Denmark)

    Bennedsen, Jens; Caspersen, Michael Edelgaard

    2007-01-01

    It is a common conception that CS1 is a very difficult course and that failure rates are high. However, until now there has only been anecdotal evidence for this claim. This article reports on a survey among institutions around the world regarding failure rates in introductory programming courses...

  9. Nontraditional Student Graduation Rate Benchmarks

    Science.gov (United States)

    Miller, Nathan B.

    2014-01-01

    The prominence of discourse on postsecondary degree completion, student persistence, and retention has increased in the national dialogue. Heightened attention to college completion rates by the federal government and pressure to tie state funding to performance metrics associated with graduation rates are catalysts for the discussion.…

  10. Can you Trust Online Ratings?

    DEFF Research Database (Denmark)

    Wulff, Julie; Hardt, Daniel

    2014-01-01

    Do user populations differ systematically in the way they express and rate sentiment? We use large collections of Danish and U.S. reviews to investigate this question, and we find evidence of important systematic differences: first, positive ratings are far more common in the U.S. data than in th...

  11. What Is a Reaction Rate?

    Science.gov (United States)

    Schmitz, Guy

    2005-01-01

    The definition of reaction rate is derived and demonstrations are made for the care to be taken while using the term. Reaction rate can be in terms of a reaction property, the extent of reaction and thus it is possible to give a definition applicable in open and closed systems.

  12. Rate of volcanism on Venus

    International Nuclear Information System (INIS)

    Fegley, B. Jr.; Prinn, R.G.

    1988-07-01

    The maintenance of the global H 2 SO 4 clouds on Venus requires volcanism to replenish the atmospheric SO 2 which is continually being removed from the atmosphere by reaction with calcium minerals on the surface of Venus. The first laboratory measurements of the rate of one such reaction, between SO 2 and calcite (CaCO 3 ) to form anhydrite (CaSO 4 ), are reported. If the rate of this reaction is representative of the SO 2 reaction rate at the Venus surface, then we estimate that all SO 2 in the Venus atmosphere (and thus the H 2 SO 4 clouds) will be removed in 1.9 million years unless the lost SO 2 is replenished by volcanism. The required rate of volcanism ranges from about 0.4 to about 11 cu km of magma erupted per year, depending on the assumed sulfur content of the erupted material. If this material has the same composition as the Venus surface at the Venera 13, 14 and Vega 2 landing sites, then the required rate of volcanism is about 1 cu km per year. This independent geochemically estimated rate can be used to determine if either (or neither) of the two discordant (2 cu km/year vs. 200 to 300 cu km/year) geophysically estimated rates is correct. The geochemically estimated rate also suggests that Venus is less volcanically active than the Earth

  13. Lung Cancer Rates by State

    Science.gov (United States)

    ... the Biggest Cancer Killer in Both Men and Women” Stay Informed Rates by State for Other Kinds of Cancer All Cancers Combined Breast Cervical Colorectal (Colon) HPV-Associated Ovarian Prostate Skin Uterine Cancer Home Lung Cancer Rates by State Language: English (US) ...

  14. Temporal Trends in Fertility Rates

    DEFF Research Database (Denmark)

    Jensen, Martin Blomberg; Priskorn, Lærke; Jensen, Tina Kold

    2015-01-01

    OBJECTIVE: Increasing age at first childbirth has been suggested to increase the risk for infertility. Our objective is to determine whether women above thirty years of age historically have been able to sustain fertility rates above replacement level. DESIGN: A descriptive nationwide Danish study...... to determine total and age specific fertility rates. RESULTS: Total fertility rate (TFR) decreased from 4.1 to 1.8 children per woman and age specific fertility also decreased from 1901 to 2014. Women aged 30-34, 35-39 or 40-44 years in the first decade of the 20th century had higher fertility rates than...... for 10% of TFR in 1901 compared with 4% in 2014 despite usage of assisted reproduction. CONCLUSION: This nationwide study shows that women above 30 years of age historically have been able to sustain fertility rates above replacement level. This implies that other factors besides age are strong...

  15. The Logic of Collective Rating

    Science.gov (United States)

    Nax, Heinrich

    2016-05-01

    The introduction of participatory rating mechanisms on online sales platforms has had substantial impact on firms' sales and profits. In this note, we develop a dynamic model of consumer influences on ratings and of rating influences on consumers, focussing on standard 5-star mechanisms as implemented by many platforms. The key components of our social influence model are the consumer trust in the `wisdom of crowds' during the purchase phase and indirect reciprocity during the rating decision. Our model provides an overarching explanation for well-corroborated empirical regularities. We quantify the performance of the voluntary rating mechanism in terms of realized consumer surplus with the no-mechanism and full-information benchmarks, and identify how it could be improved.

  16. High Rate Digital Demodulator ASIC

    Science.gov (United States)

    Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew

    1998-01-01

    The architecture of High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation in other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA's Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an over-view of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

  17. Implantation rate effects on microstructure

    International Nuclear Information System (INIS)

    Choyke, W.J.; Spitznagel, J.A.; Wood, S.; Doyle, N.J.

    1981-01-01

    We report a detailed TEM study of rate effects in a metal (304 SS) where we dope with an insoluble atom (He) and create the displacement damage with high energy Si. The rates of doping and the rates of producing lattice damage are independently varied during dual implantation. In addition to varying the doping rates of the He the magnitude of the displacement damage prior to He implantation is also varied (beam history). We find that the beam history has virtually no effect on maximum bubble size but it has a major effect on the average cavity diameter. A weak dependence of cavity number density on helium implantation rate is found. The total dislocation density is relatively independent of the doping rate and beam history at 550 and 700 0 C, whereas the loop fraction is sensitive to beam history at these temperatures. Acicular precipitate formation is weakly dependent on doping, doping rate and more strongly dependent on doping concentration and temperature. This form of solute segregation is very sensitive to beam history. (orig.)

  18. Relaxed Poisson cure rate models.

    Science.gov (United States)

    Rodrigues, Josemar; Cordeiro, Gauss M; Cancho, Vicente G; Balakrishnan, N

    2016-03-01

    The purpose of this article is to make the standard promotion cure rate model (Yakovlev and Tsodikov, ) more flexible by assuming that the number of lesions or altered cells after a treatment follows a fractional Poisson distribution (Laskin, ). It is proved that the well-known Mittag-Leffler relaxation function (Berberan-Santos, ) is a simple way to obtain a new cure rate model that is a compromise between the promotion and geometric cure rate models allowing for superdispersion. So, the relaxed cure rate model developed here can be considered as a natural and less restrictive extension of the popular Poisson cure rate model at the cost of an additional parameter, but a competitor to negative-binomial cure rate models (Rodrigues et al., ). Some mathematical properties of a proper relaxed Poisson density are explored. A simulation study and an illustration of the proposed cure rate model from the Bayesian point of view are finally presented. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Heart rate response to breathing

    DEFF Research Database (Denmark)

    Mehlsen, J; Pagh, K; Nielsen, J S

    1987-01-01

    Heart rate responses to stepwise and periodic changes in lung volume were studied in seven young healthy males. Stepwise inspiration and expiration both resulted in an increase in heart rate followed by a rapid decrease in heart rate. The fastest heart rate was reached in 1.6 +/- 0.5 s and in 3.......6 +/- 1.4 s in response to inspiration and expiration, respectively (P less than 0.01). The slowest heart rate was reached in 4.8 +/- 1.0 s and in 7.6 +/- 1.9 s in response to inspiration and expiration, respectively (P less than 0.01). Following this biphasic change the heart rate returned to a steady...... level. The difference between the fastest and the slowest heart rates was significantly larger in response to inspiration (21.7 +/- 7.3 beats per minute) than in response to expiration (12.0 +/- 7.3 beats per minute; P less than 0.01). Periodic changes in lung volume were performed with frequencies from...

  20. The Optimal Interest Rates and the Current Interest Rate System

    Directory of Open Access Journals (Sweden)

    Ioannis N. Kallianiotis

    2014-12-01

    Full Text Available The paper discusses the current target interest rate, which is closed to zero with the new experiment of quantitative easing since 2009 and has reduced the rate of return and the income and has made the real savings rate negative. This target rate has not reduced unemployment and has not improved growth (it is not optimal, but has increased the debt of individuals and the low taxes on businesses have magnified the budget deficits and the national debt. People were borrowing the present value of their uncertain future wealth and their high debt and low income raise the risk and this high risk premium heighten the interest rate on loans, especially on credit cards. The current monetary system needs to be changed and an interest rate floor on deposits (savings and an interest rate ceiling on individuals‟ loans (borrowings is necessary to improve social welfare, fairness, and justice in our society and not to support only disintermediation (financial markets. The middle class cannot work only to pay taxes and interest on its debt (redistribution of their wealth to government and banks or worse to be in chronic unemployment. Many home owners defaulted on their loans payments and their homes are foreclosed. They will end up without property (real assets. The unconcern towards the middle class will affect negatively the entire socio-economic structure of the nation and after losing its productive power, it will start declining, as history has shown to us with so many empires that do not exist anymore. We hope the leaders (the democratic governments to improve public policies, to regulate the financial market and institutions, and to satisfy their policy ultimate objective, which is citizens‟ perfection and the nation‟s highest point of prosperity.

  1. Blood Pressure vs. Heart Rate

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Blood Pressure vs. Heart Rate (Pulse) Updated:Nov 13,2017 ... This content was last reviewed October 2016. High Blood Pressure • Home • Get the Facts About HBP Introduction What ...

  2. Comprehensive Error Rate Testing (CERT)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Centers for Medicare and Medicaid Services (CMS) implemented the Comprehensive Error Rate Testing (CERT) program to measure improper payments in the Medicare...

  3. Rate Adaptive OFDMA Communication Systems

    International Nuclear Information System (INIS)

    Abdelhakim, M.M.M.

    2009-01-01

    Due to the varying nature of the wireless channels, adapting the transmission parameters, such as code rate, modulation order and power, in response to the channel variations provides a significant improvement in the system performance. In the OFDM systems, Per-Frame adaptation (PFA) can be employed where the transmission variables are fixed over a given frame and may change from one frame to the other. Subband (tile) loading offers more degrees of adaptation such that each group of carriers (subband) uses the same transmission parameters and different subbands may use different parameters. Changing the code rate for each tile in the same frame, results in transmitting multiple codewords (MCWs) for a single frame. In this thesis a scheme is proposed for adaptively changing the code rate of coded OFDMA systems via changing the puncturing rate within a single codeword (SCW). In the proposed structure, the data is encoded with the lowest available code rate then it is divided among the different tiles where it is punctured adaptively based on some measure of the channel quality for each tile. The proposed scheme is compared against using multiple codewords (MCWs) where the different code rates for the tiles are obtained using separate encoding processes. For bit interleaved coded modulation architecture two novel interleaving methods are proposed, namely the puncturing dependant interleaver (PDI) and interleaved puncturing (IntP), which provide larger interleaving depth. In the PDI method the coded bits with the same rate over different tiles are grouped for interleaving. In IntP structure the interleaving is performed prior to puncturing. The performance of the adaptive puncturing technique is investigated under constant bit rate constraint and variable bit rate. Two different adaptive modulation and coding (AMC) selection methods are examined for variable bit rate adaptive system. The first is a recursive scheme that operates directly on the SNR whereas the second

  4. Risk, ambiguity and sovereign rating

    OpenAIRE

    Di Caro, Paolo

    2014-01-01

    Decisions of investing in sovereign assets involve both risk and ambiguity. Ambiguity arises from unknown elements characterizing the value of a generic sovereign. In presence of ambiguity, ambiguity-averse investors are prone to pay for obtaining summary information such as ratings which reduces ambiguity. Ambiguity-neutral and ambiguity-averse investors, then, make decisions on the basis of different informative sources. By presenting a simple model of sovereign rating under ambiguity, thre...

  5. Reaction rate of propene pyrolysis.

    Science.gov (United States)

    Han, Peipei; Su, Kehe; Liu, Yan; Wang, Yanli; Wang, Xin; Zeng, Qingfeng; Cheng, Laifei; Zhang, Litong

    2011-10-01

    The reaction rate of propene pyrolysis was investigated based on the elementary reactions proposed in Qu et al., J Comput Chem 2009, 31, 1421. The overall reaction rate was developed with the steady-state approximation and the rate constants of the elementary reactions were determined with the variational transition state theory. For the elementary reaction having transition state, the vibrational frequencies of the selected points along the minimum energy path were calculated with density functional theory at B3PW91/6-311G(d,p) level and the energies were improved with the accurate model chemistry method G3(MP2). For the elementary reaction without transition state, the frequencies were calculated with CASSCF/6-311G(d,p) and the energies were refined with the multireference configuration interaction method MRCISD/6-311G(d,p). The rate constants were evaluated within 200-2000 K and the fitted three-parameter expressions were obtained. The results are consistent with those in the literatures in most cases. For the overall rate, it was found that the logarithm of the rate and the reciprocal temperature have excellent linear relationship above 400 K, predicting that the rate follows a typical first-order law at high temperatures of 800-2000 K, which is also consistent with the experiments. The apparent activation energy in 800-2000 K is 317.3 kJ/mol from the potential energy surface of zero Kelvin. This value is comparable with the energy barriers, 365.4 and 403.7 kJ/mol, of the rate control steps. However, the apparent activation energy, 215.7 kJ/mol, developed with the Gibbs free energy surface at 1200 K is consistent with the most recent experimental result 201.9 ± 0.6 kJ/mol. Copyright © 2011 Wiley Periodicals, Inc.

  6. Rating af banker og banksystemer

    DEFF Research Database (Denmark)

    Grosen, Anders

    2010-01-01

    Banksystemer over hele verdenen er med nød og næppe blevet reddet af diverse statslige hjælpepakker. Derfor er der i disse år øget fokus på banker og banksystemers rating. Denne interesse bliver ikke mindre af, at de statslige garantier til bankerne i mange lande udløber i de kommende år. Rating ...

  7. Evaporation rate of nucleating clusters.

    Science.gov (United States)

    Zapadinsky, Evgeni

    2011-11-21

    The Becker-Döring kinetic scheme is the most frequently used approach to vapor liquid nucleation. In the present study it has been extended so that master equations for all cluster configurations are included into consideration. In the Becker-Döring kinetic scheme the nucleation rate is calculated through comparison of the balanced steady state and unbalanced steady state solutions of the set of kinetic equations. It is usually assumed that the balanced steady state produces equilibrium cluster distribution, and the evaporation rates are identical in the balanced and unbalanced steady state cases. In the present study we have shown that the evaporation rates are not identical in the equilibrium and unbalanced steady state cases. The evaporation rate depends on the number of clusters at the limit of the cluster definition. We have shown that the ratio of the number of n-clusters at the limit of the cluster definition to the total number of n-clusters is different in equilibrium and unbalanced steady state cases. This causes difference in evaporation rates for these cases and results in a correction factor to the nucleation rate. According to rough estimation it is 10(-1) by the order of magnitude and can be lower if carrier gas effectively equilibrates the clusters. The developed approach allows one to refine the correction factor with Monte Carlo and molecular dynamic simulations.

  8. Community Rates of Breastfeeding Initiation.

    Science.gov (United States)

    Grubesic, Tony H; Durbin, Kelly M

    2016-11-01

    Breastfeeding initiation rates vary considerably across racial and ethnic groups, maternal age, and education level, yet there are limited data concerning the influence of geography on community rates of breastfeeding initiation. This study aimed to describe how community rates of breastfeeding initiation vary in geographic space, highlighting "hot spots" and "cool spots" of initiation and exploring the potential connections between race, socioeconomic status, and urbanization levels on these patterns. Birth certificate data from the Kentucky Department of Health for 2004-2010 were combined with county-level geographic base files, Census 2010 demographic and socioeconomic data, and Rural-Urban Continuum Codes to conduct a spatial statistical analysis of community rates of breastfeeding initiation. Between 2004 and 2010, the average rate of breastfeeding initiation for Kentucky increased from 43.84% to 49.22%. Simultaneously, the number of counties identified as breastfeeding initiation hot spots also increased, displaying a systematic geographic pattern in doing so. Cool spots of breastfeeding initiation persisted in rural, Appalachian Kentucky. Spatial regression results suggested that unemployment, income, race, education, location, and the availability of International Board Certified Lactation Consultants are connected to breastfeeding initiation. Not only do spatial analytics facilitate the identification of breastfeeding initiation hot spots and cool spots, but they can be used to better understand the landscape of breastfeeding initiation and help target breastfeeding education and/or support efforts.

  9. Inflation Rate Modelling in Indonesia

    Directory of Open Access Journals (Sweden)

    Rezzy Eko Caraka

    2016-10-01

    Full Text Available The purposes of this research were to analyse: (i Modelling the inflation rate in Indonesia with parametric regression. (ii Modelling the inflation rate in Indonesia using non-parametric regression spline multivariable (iii Determining the best model the inflation rate in Indonesia (iv Explaining the relationship inflation model parametric and non-parametric regression spline multivariable. Based on the analysis using the two methods mentioned the coefficient of determination (R2 in parametric regression of 65.1% while non-parametric amounted to 99.39%. To begin with, the factor of money supply or money stock, crude oil prices and the rupiah exchange rate against the dollar is significant on the rate of inflation. The stability of inflation is essential to support sustainable economic development and improve people's welfare. In conclusion, unstable inflation will complicate business planning business activities, both in production and investment activities as well as in the pricing of goods and services produced.DOI: 10.15408/etk.v15i2.3260

  10. Decreasing incidence rates of bacteremia

    DEFF Research Database (Denmark)

    Nielsen, Stig Lønberg; Pedersen, C; Jensen, T G

    2014-01-01

    BACKGROUND: Numerous studies have shown that the incidence rate of bacteremia has been increasing over time. However, few studies have distinguished between community-acquired, healthcare-associated and nosocomial bacteremia. METHODS: We conducted a population-based study among adults with first......-time bacteremia in Funen County, Denmark, during 2000-2008 (N = 7786). We reported mean and annual incidence rates (per 100,000 person-years), overall and by place of acquisition. Trends were estimated using a Poisson regression model. RESULTS: The overall incidence rate was 215.7, including 99.0 for community......-acquired, 50.0 for healthcare-associated and 66.7 for nosocomial bacteremia. During 2000-2008, the overall incidence rate decreased by 23.3% from 254.1 to 198.8 (3.3% annually, p incidence rate of community-acquired bacteremia decreased by 25.6% from 119.0 to 93.8 (3.7% annually, p

  11. Automatic Strain-Rate Controller,

    Science.gov (United States)

    1976-12-01

    D—AO37 9~e2 ROME AIR DEVELOPMENT CENTER GRIFFISS AFB N 1’ FIG 13/ 6AUTOMATIC STRAIN—RATE CONTROLLER, (U) DEC 76 R L HUNTSINGER. J A ADAMSK I...goes to zero. CONTROLLER, Leeds and Northrup Series 80 CAT with proportional band , rate , reset, and approach controls . Input from deviation output...8) through ( 16) . (8) Move the set-point slowl y up to 3 or 4. (9) If the recorder po inter hunts , adjust the func t ion controls on tine Ser

  12. Containment leakage rate testing requirements

    International Nuclear Information System (INIS)

    Arndt, E.G.

    1992-01-01

    This report presents the status of several documents under revision or development that provide requirements and guidance for testing nuclear power plant containment systems for leakage rates. These documents include the general revision to 10 CFR Part 50, Appendix J; the regulatory guide affiliated with the revision to Appendix J; the national standard that the regulatory guide endorses, ANSI/ANS-56.8, 'Containment System Leakage Rate Testing Requirements'; and the draft industry Licensing Topical Report, 'Standardized Program for Primary Containment Integrity Testing'. The actual or potential relationships between these documents are also explored

  13. Rate Change Big Bang Theory

    Science.gov (United States)

    Strickland, Ken

    2013-04-01

    The Rate Change Big Bang Theory redefines the birth of the universe with a dramatic shift in energy direction and a new vision of the first moments. With rate change graph technology (RCGT) we can look back 13.7 billion years and experience every step of the big bang through geometrical intersection technology. The analysis of the Big Bang includes a visualization of the first objects, their properties, the astounding event that created space and time as well as a solution to the mystery of anti-matter.

  14. [Awareness rate, treatment rate and control rate of dyslipidemia in Chinese adults, 2010].

    Science.gov (United States)

    Li, Jian-hong; Wang, Li-min; Mi, Sheng-quan; Zhang, Mei; Li, Yi-chong; Jiang, Yong; Xu, Yu; Dai, Meng; Wang, Lin-hong

    2012-08-01

    To explore the awareness, treatment and control rates of dyslipidemia among Chinese adults aged over 18 in 2010, and to analyze the prevalent features. 97 409 subjects aged over 18 were recruited from 162 monitoring sites around 31 provinces in China mainland in 2010, applying multi-stage stratified cluster random sampling method. Information about subjects' history of dyslipidemia, treatment and control were collected by face-to-face interview; and each subject's fasting venous blood was drawn in the morning before having food, to test total cholesterol (TC), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C) and low density lipoprotein-cholesterol (LDL-C). In total, 51 818 cases of dyslipidemia ever or now, including 2235 subjects who once suffered from dyslipidemia but had their blood lipid controlled to normal, were screened out. And the awareness, treatment and control rates were calculated by complex weighting. The awareness rate of dyslipidemia among Chinese adults was 10.93%, while the stratified rates were 6.00%, 16.75% and 18.74% in the groups of subjects aged 18 - 44, 45 - 59 and over 60 years old, respectively (χ² = 1293.02, P China, respectively (χ² = 117.04, P China, respectively (χ² = 50.71, P control rate of dyslipidemia was 3.53% among total subjects, while whose stratified rates were 1.64%, 5.49% and 6.94% in the groups of subjects aged 18 - 44, 45 - 59 and over 60 years old, respectively (χ² = 554.12, P China, respectively (χ² = 91.45, P control rates of dyslipidemia have been comparatively low among Chinese adults, especially among the population who were young, or who were from rural area or western China.

  15. 76 FR 46603 - Security Ratings

    Science.gov (United States)

    2011-08-03

    ... settled derivative securities). See Simplification of Registration of Reporting Requirements for Foreign... SECURITIES AND EXCHANGE COMMISSION 17 CFR Parts 200, 229, 230, 232, 239, 240, and 249 [Release No. 33-9245; 34-64975; File No. S7-18-08] RIN 3235-AK18 Security Ratings AGENCY: Securities and Exchange...

  16. SPECTRAL ANALYSIS OF EXCHANGE RATES

    Directory of Open Access Journals (Sweden)

    ALEŠA LOTRIČ DOLINAR

    2013-06-01

    Full Text Available Using spectral analysis is very common in technical areas but rather unusual in economics and finance, where ARIMA and GARCH modeling are much more in use. To show that spectral analysis can be useful in determining hidden periodic components for high-frequency finance data as well, we use the example of foreign exchange rates

  17. True mean rate measuring system

    International Nuclear Information System (INIS)

    Eichenlaub, D.P.

    1980-01-01

    A digital radiation-monitoring system for nuclear power plants uses digital and microprocessor circuitry to enable rapid processing of pulse information from remote radiation monitors. The pulse rates are analyzed to determine whether new pulse-rate information is statisticaly the same as that previously received and to determine the best possible averaging time, which can be changed so that the statistical error remains below a specified level while the system response time remains short. Several data modules each process the pulse-rate information from several remote radiation monitors. Each data module accepts pulse data from each radiation monitor and measures the true average or mean pulse rate of events occurring with a Poisson distribution to determine the radiation level. They then develop digital output signals which indciate the respective radiation levels and which can be transmitted via multiplexer circuits for additional processing and display. The data modules can accept signals from remote control stations or computer stations via the multiplexer circuit to change operating thresholds and alarm levels in their memories. A check module scans the various data modules to determine whether the output signals are valid. It also acts as a redundant data module and will automatically replace an inoperative unit. (DN)

  18. Speed control variable rate irrigation

    Science.gov (United States)

    Speed control variable rate irrigation (VRI) is used to address within field variability by controlling a moving sprinkler’s travel speed to vary the application depth. Changes in speed are commonly practiced over areas that slope, pond or where soil texture is predominantly different. Dynamic presc...

  19. Cohort Default Rates in Context

    Science.gov (United States)

    Looney, Shannon M.

    2011-01-01

    Burgeoning student loan debt indicates problems not only for the country's borrowers but also for the postsecondary system. The rise in student loan defaults signifies a rise in institutional cohort default rates (CDRs)--a measure of accountability that informs the government and the general public how well an institution prepares its students for…

  20. Diffusion rates for elevated releases

    International Nuclear Information System (INIS)

    Ramsdell, J.V.

    1983-11-01

    A search of the literature related to diffusion from elevated sources has determined that an adequate data base exists for use in developing parameterizations for estimating diffusion rates for material released from free standing stacks at nuclear power plants. A review of published data analyses indicates that a new parameterization of horizontal diffusion rates specifically for elevated releases is not likely to significantly change the magnitudes of horizontal diffusion coefficients on the average. However, the uncertainties associated with horizontal diffusion coefficient estimates under any given set of atmospheric conditions could be reduced by a new parameterization. Similarly, a new parameterization of vertical diffusion rates would be unlikely to significantly alter the magnitudes of diffusion coefficients for unstable atmospheric conditons. However, for neutral and stable atmospheric conditions, a new parameterization of vertical diffusion rates might increase vertical diffusion coefficients significantly. The increase would move ground-level time-integrated concentration maxima closer to the plant and would increase the maxima. 55 references, 2 figures, 4 tables

  1. Intuitive Understanding of Base Rates

    DEFF Research Database (Denmark)

    Austin, Laurel

    Purpose: This study examines whether physicians and other adults intuitively understand that the probability a positive test result is a true positive (positive predictive value, PPV) depends on the base rate of disease in the population tested. In particular, this research seeks to examine perce...

  2. Publication rates following pancreas meetings.

    Science.gov (United States)

    Timmer, A; Blum, T; Lankisch, P G

    2001-08-01

    Publication rates and determinants of publication were studied based on abstracts presented at pancreatic meetings. All abstracts presented at the 1994 and 1995 annual meetings of the European Pancreatic Club (EPC) and the American Pancreatic Association (APA) were followed up by searching MEDLINE. Publication rates were compared using log-rank tests and multiple logistic regression. The prestige of the publishing journals was compared using Kruskal-Wallis tests on scientific impact factors (SIF). Overall, 340 abstracts were presented at the EPC, and 254 were presented at the APA. Of these, 203 (59.7%, EPC) and 138 (54.3%, APA) were later published in peer-reviewed journals. Publication rates did not differ by study type or country region of origin. In addition, median SIFs were similar by conference (APA vs. EPC) and research type (basic science vs. clinical studies) (overall, 1.7). However, North American and North/West European articles were published in higher impact journals as compared with those from other countries. Publication rates and median journal SIFs in pancreas research are similar to those reported from other medical specialty meetings. There is no difference by conference, type of research, or origin (North American vs. European).

  3. Speculation, Hedging, and Interest Rates

    DEFF Research Database (Denmark)

    Buraschi, Andrea; Whelan, Paul

    of Treasury bond markets that the singleagent paradigm finds difficult to reconcile. Empirically, we test predictions from themodel using a large dataset on beliefs about fundamentals and find that: (i) shocksto disagreement lower short term interest rates; (ii) raise the slope of the yield curve;and (iii...

  4. Forecasting Interest Rates and Inflation

    DEFF Research Database (Denmark)

    Chun, Albert Lee

    the best overall for short horizon forecasts of short to medium term yields and inflation. Econometric models with shrinkage perform the best over longer horizons and maturities. Aggregating over a larger set of analysts improves inflation surveys while generally degrading interest rates surveys. We...

  5. Frame Rate and Human Vision

    Science.gov (United States)

    Watson, Andrew B.

    2012-01-01

    To enhance the quality of the theatre experience, the film industry is interested in achieving higher frame rates for capture and display. In this talk I will describe the basic spatio-temporal sensitivities of human vision, and how they respond to the time sequence of static images that is fundamental to cinematic presentation.

  6. 78 FR 15973 - Fee Rate

    Science.gov (United States)

    2013-03-13

    ... DEPARTMENT OF THE INTERIOR National Indian Gaming Commission Fee Rate Correction In notice document 2013-05334, appearing on page 14821 in the issue of Thursday, March 7, 2013, make the following correction: On page 14821, in the second column, in the eighth line from the bottom of the page, ``Dated...

  7. The dose-rate effect

    International Nuclear Information System (INIS)

    Steel, G.G.

    1989-01-01

    This paper presents calculations that illustrate two conclusions; for any particular cell type there will be a critical radius at which tumor control breaks down, and the radius at which this occurs is strongly dependent upon the low-dose-rate radiosensitivity of the cells

  8. European rating of drug harms

    NARCIS (Netherlands)

    van Amsterdam, Jan; Nutt, David; Phillips, Lawrence; van den Brink, Wim

    2015-01-01

    The present paper describes the results of a rating study performed by a group of European Union (EU) drug experts using the multi-criteria decision analysis model for evaluating drug harms. Forty drug experts from throughout the EU scored 20 drugs on 16 harm criteria. The expert group also assessed

  9. Rate meter design and construction

    International Nuclear Information System (INIS)

    Peon Aguirre, R.; Fonseca Araujo, W.H.

    1989-01-01

    An electric diagram is proposed to build a geiger detector Rate Meter, to count gamma radiation and X ray. This idea was made up with the prototype construction which has a five scales analogue display (100, 300, 1000, 3000 and 10000 c/s). (Author)

  10. Antipredator defenses predict diversification rates

    Science.gov (United States)

    Arbuckle, Kevin; Speed, Michael P.

    2015-01-01

    The “escape-and-radiate” hypothesis predicts that antipredator defenses facilitate adaptive radiations by enabling escape from constraints of predation, diversified habitat use, and subsequently speciation. Animals have evolved diverse strategies to reduce the direct costs of predation, including cryptic coloration and behavior, chemical defenses, mimicry, and advertisement of unprofitability (conspicuous warning coloration). Whereas the survival consequences of these alternative defenses for individuals are well-studied, little attention has been given to the macroevolutionary consequences of alternative forms of defense. Here we show, using amphibians as the first, to our knowledge, large-scale empirical test in animals, that there are important macroevolutionary consequences of alternative defenses. However, the escape-and-radiate hypothesis does not adequately describe them, due to its exclusive focus on speciation. We examined how rates of speciation and extinction vary across defensive traits throughout amphibians. Lineages that use chemical defenses show higher rates of speciation as predicted by escape-and-radiate but also show higher rates of extinction compared with those without chemical defense. The effect of chemical defense is a net reduction in diversification compared with lineages without chemical defense. In contrast, acquisition of conspicuous coloration (often used as warning signals or in mimicry) is associated with heightened speciation rates but unchanged extinction rates. We conclude that predictions based on the escape-and-radiate hypothesis must incorporate the effect of traits on both speciation and extinction, which is rarely considered in such studies. Our results also suggest that knowledge of defensive traits could have a bearing on the predictability of extinction, perhaps especially important in globally threatened taxa such as amphibians. PMID:26483488

  11. The influence of interest rates on the exchange rate and exchange rate volatility

    OpenAIRE

    Florin MAVRIS; Dumitru-Cristian OANEA

    2014-01-01

    The dynamic of interest rates has been the subject of attention by both traders and researchers. We see in what manner different factors that depend on the actions of central banks that influence them by using a GARCH type model and we compare its performance with other models to see what approach explains and predicts the movement of the exchange rate. To better understand the type of model that is applicable the data is tested for heteroskedasticity, and only after that the model is impleme...

  12. Content and ratings of teen-rated video games.

    Science.gov (United States)

    Haninger, Kevin; Thompson, Kimberly M

    2004-02-18

    Children's exposure to violence, blood, sexual themes, profanity, substances, and gambling in the media remains a source of public health concern. However, content in video games played by older children and adolescents has not been quantified or compared with the rating information provided to consumers by the Entertainment Software Rating Board (ESRB). To quantify and characterize the content in video games rated T (for "Teen") and to measure the agreement between the content observed in game play and the ESRB-assigned content descriptors displayed on the game box. We created a database of all 396 T-rated video game titles released on the major video game consoles in the United States by April 1, 2001, to identify the distribution of games by genre and to characterize the distribution of ESRB-assigned content descriptors. We randomly sampled 80 video game titles (which included 81 games because 1 title included 2 separate games), played each game for at least 1 hour, quantitatively assessed the content, and compared the content we observed with the content descriptors assigned by the ESRB. Depictions of violence, blood, sexual themes, gambling, and alcohol, tobacco, or other drugs; whether injuring or killing characters is rewarded or is required to advance in the game; characterization of gender associated with sexual themes; and use of profanity in dialogue, lyrics, or gestures. Analysis of all content descriptors assigned to the 396 T-rated video game titles showed 373 (94%) received content descriptors for violence, 102 (26%) for blood, 60 (15%) for sexual themes, 57 (14%) for profanity, 26 (7%) for comic mischief, 6 (2%) for substances, and none for gambling. In the random sample of 81 games we played, we found that 79 (98%) involved intentional violence for an average of 36% of game play, 73 (90%) rewarded or required the player to injure characters, 56 (69%) rewarded or required the player to kill, 34 (42%) depicted blood, 22 (27%) depicted sexual themes

  13. Optimal Discount Rates for Government Projects

    OpenAIRE

    Park, Sangkyun

    2012-01-01

    Project selection based on the net present value can be optimal only if the discount rate is optimal. The optimal discount rate for a government project can be a risk-free rate, a comparable market rate (market interest rate corresponding to the risk of cash flows to the government), or an adjusted market rate, depending on circumstances. This paper clarifies the conditions for each case. Provided that the optimal discount rate is the comparable market rate, it varies across intervention meth...

  14. Financial markets and interest rate

    Directory of Open Access Journals (Sweden)

    Dudić Zdenka

    2012-01-01

    Full Text Available The paper 'Financial Markets and Interest Rate' originated from the thesis paper. This topic is very interesting and more and more present in the recent few years. Various changes in the market, increased competition, the development of information technologies, application of innovations, all these contribute to the rapid expansion of scope and use of financial derivatives. Therefore, under these influences, oscillations in various markets are present on a daily basis, so that the vast expansion of financial contracts is present, which is mainly related to interest rates. What are the world's best-known stock markets? What are the instruments most actively traded on stock exchanges? The words LIBOR and BBA LIBOR are frequently heard in today's media. What is LIBOR? What is BBA LIBOR? How and when is it determined? Where is LIBOR used?.

  15. What Determines Star Formation Rates?

    Science.gov (United States)

    Evans, Neal John

    2017-06-01

    The relations between star formation and gas have received renewed attention. We combine studies on scales ranging from local (within 0.5 kpc) to distant galaxies to assess what factors contribute to star formation. These include studies of star forming regions in the Milky Way, the LMC, nearby galaxies with spatially resolved star formation, and integrated galaxy studies. We test whether total molecular gas or dense gas provides the best predictor of star formation rate. The star formation ``efficiency," defined as star formation rate divided by mass, spreads over a large range when the mass refers to molecular gas; the standard deviation of the log of the efficiency decreases by a factor of three when the mass of relatively dense molecular gas is used rather than the mass of all the molecular gas. We suggest ways to further develop the concept of "dense gas" to incorporate other factors, such as turbulence.

  16. The instantaneous frequency rate spectrogram

    Science.gov (United States)

    Czarnecki, Krzysztof

    2016-01-01

    An accelerogram of the instantaneous phase of signal components referred to as an instantaneous frequency rate spectrogram (IFRS) is presented as a joint time-frequency distribution. The distribution is directly obtained by processing the short-time Fourier transform (STFT) locally. A novel approach to amplitude demodulation based upon the reassignment method is introduced as a useful by-product. Additionally, an estimator of energy density versus the instantaneous frequency rate (IFR) is proposed and referred to as the IFR profile. The energy density is estimated based upon both the classical energy spectrogram and the IFRS smoothened by the median filter. Moreover, the impact of an analyzing window width, additive white Gaussian noise and observation time is tested. Finally, the introduced method is used for the analysis of the acoustic emission of an automotive engine. The recording of the engine of a Lamborghini Gallardo is analyzed as an example.

  17. 13 CFR 301.4 - Investment rates.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Investment rates. 301.4 Section... ELIGIBILITY, INVESTMENT RATE AND PROPOSAL AND APPLICATION REQUIREMENTS Investment Rates and Matching Share Requirements § 301.4 Investment rates. (a) Minimum Investment Rate. There is no minimum Investment Rate for a...

  18. Injury rates in Shotokan karate

    OpenAIRE

    Critchley, G. R.; Mannion, S.; Meredith, C.

    1999-01-01

    OBJECTIVE: To document the injury rate in three British Shotokan karate championships in consecutive years. In these tournaments strict rules governed contact, with only "light" or "touch" contact allowed. Protective padding for the head, hands, or feet was prohibited. METHODS: Prospective recording of injuries resulting from 1770 bouts in three national competitions of 1996, 1997, and 1998. Details of ages and years of karate experience were also obtained. RESULTS: 160 injuries were su...

  19. Exchange Rate and Inflation Dynamics

    OpenAIRE

    Eatzaz Ahmad; Saima Ahmed Ali

    1999-01-01

    This paper studies simultaneous determination of nominal exchange rate and domestic price level in Pakistan. The estimated model contains sufficient built-in dynamics to trace the pattern and speed of adjustment in the two variables in response to temporary or permanent shocks. The two domestic shocks considered in the paper are monetary and real shocks, while the three external shocks considered are import price, export price and foreign exchange reserves shocks. The study finds that the imp...

  20. Gig economy, rating, labour relationship

    OpenAIRE

    Gemma Pacella

    2017-01-01

    In the era of gig economy, the job performance is now influenced by the customer rating system. A new London’s Employment Tribunal judgment approaches the Uber London issue focusing also on customer feedback. Since drivers are qualified as workers, not self-employed, as the English Court ruled on, this article tooks a position about on-line feedback incidence on job relationship. Referring to customer’s opinion, the employer exercises control on services performed by each worker, whereas Ital...

  1. Extended Power Up-rates

    International Nuclear Information System (INIS)

    Jon Ball

    2006-01-01

    Full text of publication follows: Nuclear energy is a reliable and cost-competitive global source of power. With rising oil and gas prices, nuclear continues to provide economic and environmental benefits. Extended Power Up-rate (EPU) provides a means for existing nuclear assets to generate increased power and substantially reduce electrical generation costs. GE Energy's Nuclear Business is the global leader in boiling water reactor (BWR) technology. The experience-base of plants that have successfully achieved EPU includes Spain, Switzerland, Sweden, Germany and the United States. The GE experience-base includes fourteen BWRs with over fifty-eight reactor-years of operating experience at EPU conditions. Other than the expected plant modifications needed to accommodate higher steam flows, flow-induced vibration (FIV) has been identified as the major area of concern when up-rating. Two plants have experienced damage to their steam dryers that has lead to an extensive program to improve the understanding of the effects of up-rates. This program includes extensive in-plant data collection, the development of a scale model test facility to study components susceptible to FIV and improvements in analytical techniques for evaluating loading on reactor internals. As global energy demands increase, oil and gas prices escalate, and environmental concerns over greenhouse effects challenge us to find environmentally friendly sources of energy, Nuclear is the most viable and economical source of power in the world. With a focused effort on plant reliability, existing plants can undergo Extended Power Up-rate, and continue to meet the ever-increasing energy demands in the world. (author)

  2. Rates for the competitive market

    International Nuclear Information System (INIS)

    Ander, B.; Watson, I.; Snelson, K.

    1997-01-01

    The discussion panel consisted of Bruce Ander of Pamco Atlas, Ian Watson, Chair of the Ontario Chamber of Commerce Energy Committee, and Ken Snelson, Principal of Snelson International Energy. Ian Watson shared his membership's views on the future supply of electric power under a competitive energy system in Ontario, stressing the need for the government to instruct Ontario Hydro to bring forward a transmission rate to the Ontario Energy Board in 1997, and for legislation to allow independent buyers and sellers to contract with one another to use that transmission rate outside the control of Ontario Hydro. He also expressed concern about Ontario Hydro's anti-competitive load retention rate which was an obvious bid to retain its major customers. Ken Snelson reported on a review of the effects of competition on Canada's long-term energy outlook. He predicted that in a competitive market with full retail access, customers can expect a lot more choice; independent producers also will have many more options for selling power

  3. Status of rates and rate equations for thermal leptogenesis

    Science.gov (United States)

    Biondini, S.; Bödeker, D.; Brambilla, N.; Garny, M.; Ghiglieri, J.; Hohenegger, A.; Laine, M.; Mendizabal, S.; Millington, P.; Salvio, A.; Vairo, A.

    2018-02-01

    In many realizations of leptogenesis, heavy right-handed neutrinos play the main role in the generation of an imbalance between matter and antimatter in the early Universe. Hence, it is relevant to address quantitatively their dynamics in a hot and dense environment by taking into account the various thermal aspects of the problem at hand. The strong washout regime offers an interesting framework to carry out calculations systematically and reduce theoretical uncertainties. Indeed, any matter-antimatter asymmetry generated when the temperature of the hot plasma T exceeds the right-handed neutrino mass scale M is efficiently erased, and one can focus on the temperature window T ≪ M. We review recent progress in the thermal field theoretic derivation of the key ingredients for the leptogenesis mechanism: the right-handed neutrino production rate, the CP asymmetry in the heavy-neutrino decays and the washout rates. The derivation of evolution equations for the heavy-neutrino and lepton-asymmetry number densities, their rigorous formulation and applicability are also discussed.

  4. Response rate and reinforcement rate in Pavlovian conditioning.

    Science.gov (United States)

    Harris, Justin A; Carpenter, Joanne S

    2011-10-01

    Four experiments used delay conditioning of magazine approach in rats to investigate the relationship between the rate of responding, R, to a conditioned stimulus (CS) and the rate, r, at which the CS is reinforced with the unconditioned stimulus (US). Rats were concurrently trained with four variable-duration CSs with different rs, either as a result of differences in the mean CS-US interval or in the proportion of CS presentations that ended with the US. In each case, R was systematically related to r, and the relationship was very accurately characterized by a hyperbolic function, R = Ar/(r +c). Accordingly, the reciprocal of these two variables-response interval, I (= 1/R), and CS-US interval, i (= 1/r) - were related by a simple affine (straight line) transformation, I = mi+b. This latter relationship shows that each increment in the time that the rats had to wait for food produced a linear increment in the time they waited between magazine entries. We discuss the close agreement between our findings and the Matching Law (Herrnstein, 1970) and consider their implications for both associative theories (e.g., Rescorla & Wagner, 1972) and nonassociative theories (Gallistel & Gibbon, 2000) of conditioning. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  5. Heart rate variability in newborns.

    Science.gov (United States)

    Javorka, K; Lehotska, Z; Kozar, M; Uhrikova, Z; Kolarovszki, B; Javorka, M; Zibolen, M

    2017-09-22

    Heart rate (HR) and heart rate variability (HRV) in newborns is influenced by genetic determinants, gestational and postnatal age, and other variables. Premature infants have a reduced HRV. In neonatal HRV evaluated by spectral analysis, a dominant activity can be found in low frequency (LF) band (combined parasympathetic and sympathetic component). During the first postnatal days the activity in the high frequency (HF) band (parasympathetic component) rises, together with an increase in LF band and total HRV. Hypotrophy in newborn can cause less mature autonomic cardiac control with a higher contribution of sympathetic activity to HRV as demonstrated by sequence plot analysis. During quiet sleep (QS) in newborns HF oscillations increase - a phenomenon less expressed or missing in premature infants. In active sleep (AS), HRV is enhanced in contrast to reduced activity in HF band due to the rise of spectral activity in LF band. Comparison of the HR and HRV in newborns born by physiological vaginal delivery, without (VD) and with epidural anesthesia (EDA) and via sectio cesarea (SC) showed no significant differences in HR and in HRV time domain parameters. Analysis in the frequency domain revealed, that the lowest sympathetic activity in chronotropic cardiac chronotropic regulation is in the VD group. Different neonatal pathological states can be associated with a reduction of HRV and an improvement in the health conditions is followed by changes in HRV what can be use as a possible prognostic marker. Examination of heart rate variability in neonatology can provide information on the maturity of the cardiac chronotropic regulation in early postnatal life, on postnatal adaptation and in pathological conditions about the potential dysregulation of cardiac function in newborns, especially in preterm infants.

  6. Global warming and interest rate

    International Nuclear Information System (INIS)

    Rey, Francisco C.

    1999-01-01

    The socio-economical growth of our country will yield unavoidably a sustained growth on the energy demand, particularly on the electricity demand. If the expected assumptions are fulfilled, the needed power needed to cover the electrical demand between 1997 and 2020 will almost triple, and the natural gas consumption by the generating facilities and CO 2 emissions in that sector will multiply by five. If the emissions of other sector grow at the same rate as those of the electric sector the level of the emissions in our country will be equivalent to those of the developed countries at present. It is imperative to put limits to the growth of those emissions. In order to avoid that limiting of the emissions to be just a declaration, it is necessary to find and implement mechanisms that will lead to that goal. In the electric sector, and in order to promote the use of energy sources free of those emissions, the possible measures are: Application of an emission tax of U$ 10 (or higher) per ton of CO 2 and use of the resulting funds to cause a decrease in the interest rate applied to electric generation projects which do not emit greenhouse gases. Contributions by the countries responsible for the present level of CO 2 in the atmosphere to lower the incidence of the initial capital costs on the generation costs for the same type of projects (via low rate loans or subsidies). Being active any one of these two mechanisms (or both), will provoke those clean generation sources to compete successfully and will allow them to be a valuable tool to effectively diminish the growth of the emissions of those gases from the electric sector. Besides, a tax of such magnitude would not provoke an important increase on the electric energy prices. If any mechanism is implemented which intends to effectively diminish the CO 2 emissions, the first important project to be completed is the completion of the Atucha II power station. (author)

  7. Atmospheric radiation flight dose rates

    Science.gov (United States)

    Tobiska, W. K.

    2015-12-01

    Space weather's effects upon the near-Earth environment are due to dynamic changes in the energy transfer processes from the Sun's photons, particles, and fields. Of the domains that are affected by space weather, the coupling between the solar and galactic high-energy particles, the magnetosphere, and atmospheric regions can significantly affect humans and our technology as a result of radiation exposure. Space Environment Technologies (SET) has been conducting space weather observations of the atmospheric radiation environment at aviation altitudes that will eventually be transitioned into air traffic management operations. The Automated Radiation Measurements for Aerospace Safety (ARMAS) system and Upper-atmospheric Space and Earth Weather eXperiment (USEWX) both are providing dose rate measurements. Both activities are under the ARMAS goal of providing the "weather" of the radiation environment to improve aircraft crew and passenger safety. Over 5-dozen ARMAS and USEWX flights have successfully demonstrated the operation of a micro dosimeter on commercial aviation altitude aircraft that captures the real-time radiation environment resulting from Galactic Cosmic Rays and Solar Energetic Particles. The real-time radiation exposure is computed as an effective dose rate (body-averaged over the radiative-sensitive organs and tissues in units of microsieverts per hour); total ionizing dose is captured on the aircraft, downlinked in real-time, processed on the ground into effective dose rates, compared with NASA's Langley Research Center (LaRC) most recent Nowcast of Atmospheric Ionizing Radiation System (NAIRAS) global radiation climatology model runs, and then made available to end users via the web and smart phone apps. Flight altitudes now exceed 60,000 ft. and extend above commercial aviation altitudes into the stratosphere. In this presentation we describe recent ARMAS and USEWX results.

  8. Dose and dose rate monitor

    International Nuclear Information System (INIS)

    Novakova, O.; Ryba, J.; Slezak, V.; Svobodova, B.; Viererbl, L.

    1984-10-01

    The methods are discussea of measuring dose rate or dose using a scintillation counte. A plastic scintillator based on polystyrene with PBD and POPOP activators and coated with ZnS(Ag) was chosen for the projected monitor. The scintillators were cylindrical and spherical in shape and of different sizes; black polypropylene tubes were chosen as the best case for the probs. For the counter with different plastic scintillators, the statistical error 2σ for natural background was determined. For determining the suitable thickness of the ZnS(Ag) layer the energy dependence of the counter was measured. Radioisotopes 137 Cs, 241 Am and 109 Cd were chosen as radiation sources. The best suited ZnS(Ag) thickness was found to be 0.5 μm. Experiments were carried out to determine the directional dependence of the detector response and the signal to noise ratio. The temperature dependence of the detector response and its compensation were studied, as were the time stability and fatigue manifestations of the photomultiplier. The design of a laboratory prototype of a dose rate and dose monitor is described. Block diagrams are given of the various functional parts of the instrument. The designed instrument is easiiy portable, battery powered, measures dose rates from natural background in the range of five orders, i.e., 10 -2 to 10 3 nGy/s, and allows to determine a dose of up to 10 mGy. Accouracy of measurement in the energy range of 50 keV to 1 MeV is better than +-20%. (E.S.)

  9. NPP ATMS Snowfall Rate Product

    Science.gov (United States)

    Meng, Huan; Ferraro, Ralph; Kongoli, Cezar; Wang, Nai-Yu; Dong, Jun; Zavodsky, Bradley; Yan, Banghua

    2015-01-01

    Passive microwave measurements at certain high frequencies are sensitive to the scattering effect of snow particles and can be utilized to retrieve snowfall properties. Some of the microwave sensors with snowfall sensitive channels are Advanced Microwave Sounding Unit (AMSU), Microwave Humidity Sounder (MHS) and Advance Technology Microwave Sounder (ATMS). ATMS is the follow-on sensor to AMSU and MHS. Currently, an AMSU and MHS based land snowfall rate (SFR) product is running operationally at NOAA/NESDIS. Based on the AMSU/MHS SFR, an ATMS SFR algorithm has been developed recently. The algorithm performs retrieval in three steps: snowfall detection, retrieval of cloud properties, and estimation of snow particle terminal velocity and snowfall rate. The snowfall detection component utilizes principal component analysis and a logistic regression model. The model employs a combination of temperature and water vapor sounding channels to detect the scattering signal from falling snow and derive the probability of snowfall (Kongoli et al., 2015). In addition, a set of NWP model based filters is also employed to improve the accuracy of snowfall detection. Cloud properties are retrieved using an inversion method with an iteration algorithm and a two-stream radiative transfer model (Yan et al., 2008). A method developed by Heymsfield and Westbrook (2010) is adopted to calculate snow particle terminal velocity. Finally, snowfall rate is computed by numerically solving a complex integral. NCEP CMORPH analysis has shown that integration of ATMS SFR has improved the performance of CMORPH-Snow. The ATMS SFR product is also being assessed at several NWS Weather Forecast Offices for its usefulness in weather forecast.

  10. Reaction rates for neutrino processes

    International Nuclear Information System (INIS)

    Shalitin, D.

    1978-01-01

    Some integrals involved in neutrino processes are evaluated by transformation to a special system of reference - usually to the center of mass system (CM). Rather simple analytic expressions are obtained for reaction rates and, though less simple, for moments. An interesting result thus obtained is for an isotropic interaction (in CM) of a neutrino with a monoenergetic isotropic gas of extreme relativistic electrons: it is found that the probability of the scattered neutrino to have energy in a certain range is independent of this energy. (Auth.)

  11. Charge balancing fill rate monitor

    International Nuclear Information System (INIS)

    Rothman, J.L.; Blum, E.B.

    1995-01-01

    A fill rate monitor has been developed for the NSLS storage rings to allow machine tuning over a very large dynamic range of beam current. Synchrotron light, focused on a photodiode, produces a signal proportional to the beam current. A charge balancing circuit processes the diode current, creating an output signal proportional to the current injected into the ring. The unit operates linearly over a dynamic range of 120 dB and can resolve pulses of injected beam as small as 1 μA

  12. CHANGES IN EXCHANGE RATE REGIMES

    Directory of Open Access Journals (Sweden)

    Carmen SANDU (TODERASCU

    2014-06-01

    Full Text Available The experience of recentyears showsthat it hasa fundamentalroleformation mechanismof the exchange rateinmacroeconomic stabilization. Global economiccrises, oil shockshave shownthe difficultyoffloatingsustainabilitybyparticipants in the system. EuropeanMonetary System, focused onconcertedfloatingcurrenciestoECU, was formedunder the conditionsin which somecountries have adoptedregional monetaryarrangements(EU countries, with suchbasescurrencyregimeshybridthat combinesspecific mechanismsto those offixedratefree floating. This paperaims to demonstratethe important role thatithasthe choice ofexchange rateregimeas abasic elementin thefoundationofmacroeconomic stabilizationinstruments. Consideredan expression of thestateof the domestic economyandinternationalcompetitiveness, the exchange rate is determined bya complex set ofexternal factorsorinternalstabilityisa prerequisite forthe crisis.

  13. Rating prediction using textual reviews

    Science.gov (United States)

    NithyaKalyani, A.; Ushasukhanya, S.; Nagamalleswari, TYJ; Girija, S.

    2018-04-01

    Information today is present in the form of opinions. Two & a half quintillion bytes are exchanged today in Internet everyday and a large amount consists of people’s speculation and reflection over an issue. It is the need of the hour to be able to mine this information that is presented to us. Sentimental analysis refers to mining of this raw information to make sense. The discipline of opinion mining has seen a lot of encouragement in the past few years augmented by involvement of social media like Instagram, Facebook, and twitter. The hidden message in this web of information is useful in several fields such as marketing, political polls, product review, forecast market movement, Identifying detractor and promoter. In this endeavor, we introduced sentiment rating system for a particular text or paragraph to determine the opinions polarity. Firstly we resolve the searching problem, tokenization, classification, and reliable content identification. Secondly we extract probability for given text or paragraph for both positive & negative sentiment value using naive bayes classifier. At last we use sentiment dictionary (SD), sentiment degree dictionary (SDD) and negation dictionary (ND) for more accuracy. Later we blend all above mentioned factor into given formula to find the rating for the review.

  14. Sedimentation rate in Ariake Sea

    International Nuclear Information System (INIS)

    Momoshima, Noriyuki; Nishio, Souma; Honza, Eiichi

    2004-01-01

    rate by 210 Pb(22 y) and 137 Cs(30 y). The depth profiles of the Sta.2 which is about 10 km away form the mouth of the Chikugo river showed almost constant 210 Pb concentration at upper several cm and subsequent decrease in concentration in deeper layers down to 24 cm. The sedimentation rate of 0.11 g/cm 2 /y was obtained by the decline of excess 210 Pb, yielding 0.24 cm/y sedimentation rate at the sediment surface. Another core at Sta. 4 which is south west of the Sta. 2 showed very slow sedimentation rate. The 137 Cs supplied by atmospheric nuclear tests was detected down to 34 cm at Sta. 2, the year calculated for 34 cm depth using the 210 Pb sedimentation rate was older than 1954 for the initiation of 137 Cs contamination by nuclear tests. The 137 Cs profile at Sta. 4 showed very slow sedimentation rate as observed for 210 Pb, suggesting necessity of thinner sectioning the core. There are several rivers are flowing into the Ariake sea and the Chikugo river is one of the major rivers. The Sta. 2 would be affected mostly by the Chikugo river and thus would record historical change of the environmental condition related to the Chikugo river. Anti-clockwise current is flowing in inner area of the Ariake sea, which would bring suspended materials supplied from the Chikugo river to the west of the Ariake sea. Larger materials would be accumulated at closer area to the mouth of the Chikugo river and less would be transported to the West. The slower accumulation rate at Sta. 4 than Sta. 2 is reasonable considering the situation mentioned above. The model calculation on 137 Cs and 210 Pb distribution for Sta. 2 suggests that assumption of a constant mixing at upper layers for 210 Pb and 137 Cs gives inconsistency with the observed distribution, 137 Cs was observed at deeper depth that estimated from 210 Pb sedimentation rate. The inventory of 137 Cs at Sta. 2 decay corrected to 2003 was 17.8% of total deposition at ground surface and 2.8% at Sta. 4, this would be related to

  15. Bypass flow rate control method

    International Nuclear Information System (INIS)

    Kiyama, Yoichi.

    1997-01-01

    In a PWR type reactor, bypass flow rate is controlled by exchanging existent jetting hole plugs of a plurality of nozzles disposed to the upper end of incore structures in order to flow a portion of primary coolants as a bypass flow to the upper portion of the pressure vessel. Two kinds of exchange plugs, namely, a first plug and a second plug each having a jetting out hole of different diameter are used as exchange plugs. The first plug has the diameter as that of an existent plug and the second plug has a jetting out hole having larger diameter than that of the existent plug. Remained extent plugs are exchanged to a combination of the first and the second plugs without exchanging existent plugs having seizing with the nozzles, in which the number and the diameter of the jetting out holes of the second plugs are previously determined based on predetermined total bypass flow rate to be jetted from the entire plugs after exchange of plugs. (N.H.)

  16. Gig economy, rating, labour relationship

    Directory of Open Access Journals (Sweden)

    Gemma Pacella

    2017-04-01

    Full Text Available In the era of gig economy, the job performance is now influenced by the customer rating system. A new London’s Employment Tribunal judgment approaches the Uber London issue focusing also on customer feedback. Since drivers are qualified as workers, not self-employed, as the English Court ruled on, this article tooks a position about on-line feedback incidence on job relationship. Referring to customer’s opinion, the employer exercises control on services performed by each worker, whereas Italian Legal System bounds it, within the meaning of article 4 of Worker’s Statutory. On the other hand, the customer rating can be considered as a type of control on the business organization, in observance of limits established by the same article.Moreover, the paper’s purpose is to inquire about the feedback positive impact on workers: customer satisfaction could provide business bonus, or it could become an evidence against employer in a court case.

  17. 47 CFR 65.800 - Rate base.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Rate base. 65.800 Section 65.800 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES (CONTINUED) INTERSTATE RATE OF RETURN PRESCRIPTION PROCEDURES AND METHODOLOGIES Rate Base § 65.800 Rate base. The rate base shall...

  18. 78 FR 44459 - Rate Regulation Reforms

    Science.gov (United States)

    2013-07-24

    ... the interest rate. A simple multiplication of the nominal rate by the portion of the year covered by... makes technical changes to the full and simplified rate procedures; changes the interest rate that... allocation methodology for cross-over traffic. Part IV sets out the change in the interest rate carriers must...

  19. 27 CFR 70.93 - Interest rate.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Interest rate. 70.93... Excise and Special (Occupational) Tax Interest § 70.93 Interest rate. (a) In general. The interest rate... annual percentage rate of interest will exceed the prescribed rate of interest. (b) Applicability of...

  20. 76 FR 59767 - Interest Rates; Notice

    Science.gov (United States)

    2011-09-27

    ... SMALL BUSINESS ADMINISTRATION Interest Rates; Notice AGENCY: Small Business Administration. The Small Business Administration publishes an interest rate called the optional ``peg'' rate (13 CFR 120... fluctuating interest rate SBA loans. This rate will be 3.125 (3\\1/8\\) percent for the October-December quarter...

  1. 7 CFR 1779.33 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Interest rates. 1779.33 Section 1779.33 Agriculture... (CONTINUED) WATER AND WASTE DISPOSAL PROGRAMS GUARANTEED LOANS § 1779.33 Interest rates. (a) General. Rates.... Interest rates will be those rates customarily charged borrowers in similar circumstances in the ordinary...

  2. 7 CFR 4279.125 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rates. 4279.125 Section 4279.125 Agriculture... Interest rates. The interest rate for the guaranteed loan will be negotiated between the lender and the applicant and may be either fixed or variable as long as it is a legal rate. Interest rates will not be more...

  3. 7 CFR 1980.320 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Interest rate. 1980.320 Section 1980.320 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.320 Interest rate. The interest rate must not... interest rate over the life of the loan. The rate shall be agreed upon by the borrower and the Lender and...

  4. 7 CFR 3575.33 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rates. 3575.33 Section 3575.33 Agriculture... GENERAL Community Programs Guaranteed Loans § 3575.33 Interest rates. (a) General. Rates will be negotiated between the lender and the borrower. They may be either fixed or variable rates. Interest rates...

  5. 7 CFR 1714.4 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Interest rates. 1714.4 Section 1714.4 Agriculture... PRE-LOAN POLICIES AND PROCEDURES FOR INSURED ELECTRIC LOANS General § 1714.4 Interest rates. (a) Municipal rate loans. Each advance of funds on a municipal rate loan shall bear interest at a single rate...

  6. Winning the rate base battle

    International Nuclear Information System (INIS)

    Steigelmann, W.H.

    1986-01-01

    In most states, all costs associated with building new power plants and other facilities are born by the owning utility until the facility becomes useful to customers. For a nuclear plant, this means that a utility must raise several billion dollars in capital over a period of 10 to 20 years, often undergrowing pressures to cancel the project. None of the possible ways of mitigating rate shock is free of controversy, but the objective should be to do that which is most equitable and has least adverse effects. The basic options are discussed, and all but one involves phasing in over time the full economic effects of the new plant. The impacts on average electricity price of three of the seven approaches are illustrated

  7. Radiation dose rate measuring device

    International Nuclear Information System (INIS)

    Sorber, R.

    1987-01-01

    A portable device is described for in-field usage for measuring the dose rate of an ambient beta radiation field, comprising: a housing, substantially impervious to beta radiation, defining an ionization chamber and having an opening into the ionization chamber; beta radiation pervious electrically-conductive window means covering the opening and entrapping, within the ionization chamber, a quantity of gaseous molecules adapted to ionize upon impact with beta radiation particles; electrode means disposed within the ionization chamber and having a generally shallow concave surface terminating in a generally annular rim disposed at a substantially close spacing to the window means. It is configured to substantially conform to the window means to define a known beta radiation sensitive volume generally between the window means and the concave surface of the electrode means. The concave surface is effective to substantially fully expose the beta radiation sensitive volume to the radiation field over substantially the full ambient area faced by the window means

  8. Systematic Differences and Random Rates

    DEFF Research Database (Denmark)

    Knudsen, Thorbjørn; Levinthal, Daniel A.; Winter, Sidney G.

    2017-01-01

    evolutionary dynamics of firm entry, and the subsequent consolidation of market share and industry shake-out is considered, then during early epochs of industry evolution, one would tend to observe systematic differences in growth rates associated with firm’s competitive fitness. Thus, it is only......A fundamental premise of the strategy field is the existence of persistent firm level differences in resources and capabilities. This property of heterogeneity should express itself in a variety of empirical “signatures,” such as firm performance and arguably systematic and persistent differences...... component, but for much of an industry’s and firm’s history should have a random pattern consistent with the Gibrat property. The intuition is as follows. In a Cournot equilibrium, firms of better “type” (i.e., lower cost) realize a larger market share, but act with some restraint on their choice...

  9. Flow, diffusion, and rate processes

    International Nuclear Information System (INIS)

    Sieniutycz, S.; Salamon, P.

    1992-01-01

    This volume contains recent results obtained for the nonequilibrium thermodynamics of transport and rate processes are reviewed. Kinetic equations, conservation laws, and transport coefficients are obtained for multicomponent mixtures. Thermodynamic principles are used in the design of experiments predicting heat and mass transport coefficients. Highly nonstationary conditions are analyzed in the context of transient heat transfer, nonlocal diffusion in stress fields and thermohydrodynamic oscillatory instabilities. Unification of the dynamics of chemical systems with other sorts of processes (e.g. mechanical) is given. Thermodynamics of reacting surfaces is developed. Admissible reaction paths are studied and a consistency of chemical kinetics with thermodynamics is shown. Oscillatory reactions are analyzed in a unifying approach showing explosive, conservation or damped behavior. A comprehensive review of transport processes in electrolytes and membranes is given. Applications of thermodynamics to thermoelectric systems and ionized gas (plasma) systems are reviewed

  10. Creep at very low rates

    CSIR Research Space (South Africa)

    Nabarro, FRN

    2002-02-01

    Full Text Available stream_source_info nabarro_2002.pdf.txt stream_content_type text/plain stream_size 31615 Content-Encoding ISO-8859-1 stream_name nabarro_2002.pdf.txt Content-Type text/plain; charset=ISO-8859-1 Creep at Very Low Rates F... to the necessary condition: vol. 29, p. 1285. 10. J.E. Harris, R.B. Jones, G.W. Greenwood, and M.J. Ward: J. Aust.L/b . m/2psp [5] Inst. Met., 1969, vol. 14, p. 154. 11. G.B. Gibbs: Mem. Sci. Rev. Met., 1965, vol. 62, p. 781.Even if this condition is satisfied, H...

  11. 19 CFR 159.33 - Proclaimed rate.

    Science.gov (United States)

    2010-04-01

    ... currency involved, such proclaimed rate shall be used unless it varies by 5 percent or more from the... (CONTINUED) LIQUIDATION OF DUTIES Conversion of Foreign Currency § 159.33 Proclaimed rate. If a rate of...

  12. Reduced Disparities in Birth Rates Among Teens

    Science.gov (United States)

    ... Teens Winnable Battles Social Media at CDC Reduced Disparities in Birth Rates among Teens Aged 15–19 ... Pregnancy Prevention Community-Wide Initiative. National Rates and Disparities Nationally, the teen birth rate (number of births ...

  13. 78 FR 73821 - Publication of Depreciation Rates

    Science.gov (United States)

    2013-12-09

    ... DEPARTMENT OF AGRICULTURE Rural Utilities Service Publication of Depreciation Rates AGENCY: Rural Utilities Service. ACTION: Notice of Depreciation Rates for Telecommunications Plant. SUMMARY: The United... programs, including the Telecommunications Program. RUS announces the depreciation rates for...

  14. A Decision Model for Merging Base Operations: Outsourcing Pest Management on Joint Base Anacostia-Bolling

    Science.gov (United States)

    2011-11-30

    OH: South- Western Cengage Learning. Mankiw , N. G. (2006). Principles of economics (4th ed.). Mason, OH: Thompson South- Western. Private...When the choice to in-source or outsource an installation function or service requirement exists, in these challenging economic times, it is now more...decision uncertainties. When the choice to in-source or outsource an installation function or service requirement exists, in these challenging economic

  15. Competition between Catolaccus grandis (Hymenoptera: Pteromalidae and Bracon vulgaris (Hymenoptera: Braconidae, parasitoids of the Boll Weevil

    Directory of Open Access Journals (Sweden)

    Francisco de Sousa Ramalho

    2007-05-01

    Full Text Available The competition between populations of the parasitoids C. grandis and B. vulgaris was studied using larvae of Euscepes postfasciatus (Fairmaire as an alternative host. A series of biological parameters was observed and related to the competitive abilities of both parasitoid species. They were capable of colonizing and maintaining their populations regardless of host location. The population growth of C. grandis and B. vulgaris, based on fecundity was not affected by the competition. The parasitism and survivorship to the adult stage were affected by competition, except when the host was located at the bottom of the rearing cage. C. grandis performed better than B. vulgaris independently of the competition and host location, but it did not exclude the other species.Catolaccus grandis (Burks e Bracon vulgaris Ashmead são os principais parasitóides do bicudo-do-algodoeiro Anthonomus grandis Boheman no Nordeste do Brasil. É importante que se determinem as interações entre esses parasitóides e o seu efeito em programas de controle biológico dessa praga com os mesmos. A competição entre os parasitóides C. grandis e B. vulgaris foi estudada, utilizando-se larvas de Euscepes postfasciatus Fairmaire como hospedeiro alternativo. A fecundidade de C. grandis e B. vulgaris baseada na produção de ovos, não foi afetada pela competição, mas o parasitismo e a produção de adultos desses parasitóides foram afetados pela competição, exceto quando o hospedeiro se encontrava na base da caixa de criação. Independentemente da competição e da localização do hospedeiro, C. grandis apresentou melhor desempenho que B. vulgaris, mas não excluiu as populações da outra espécie de parasitóide.

  16. Selection of Bacillus thuringiensis strains toxic to cotton boll weevil (Anthonomus grandis, Coleoptera: Curculionidae) larvae.

    Science.gov (United States)

    Pérez, Melisa P; Sauka, Diego H; Onco, María I; Berretta, Marcelo F; Benintende, Graciela B

    Preliminary bioassays with whole cultures (WC) of 124 Bacillus thuringiensis strains were performed with neonate larvae of Anthonomus grandis, a major cotton pest in Argentina and other regions of the Americas. Three exotic and four native strains were selected for causing more than 50% mortality. All of them were β-exotoxin producers. The native strains shared similar morphology of parasporal crystals, similar protein pattern and identical insecticidal gene profiles. These features resembled Lepidoptera-toxic strains. Furthermore, these strains showed a Rep-PCR pattern identical to lepidoptericidal strain HD-1, suggesting that these strains may belong to serovar kurstaki. However, some differences were observed in the plasmid profiles and in the production of β-exotoxin. To determine the culture fractions where the insecticidal metabolites were present, bioassays including resuspended spore-crystal pellets, filtered supernatants (FS) were compared with those of WC. Both fractions tested showed some level of insecticidal activity. The results may suggest that the main toxic factors can be found in FS and could be directly correlated with the presence of β-exotoxin. Based on the bioassays with FS and autoclaved FS, the participation of thermolabile virulence factors such as Cry1I in toxicity is neither discarded. In the selected strains, β-exotoxin would be the major associated virulence factor; therefore, their use in biological control of A. grandis should be restricted. Nevertheless, these strains could be the source of genes (e.g., cry1Ia) to produce transgenic cotton plants resistant to this pest. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Registration of 'Bolles' hard red spring wheat with high grain protein concentration and superior baking quality

    Science.gov (United States)

    The hard red spring wheat market class in the U.S. commands the highest prices on the worldwide wheat markets because of its high protein content, strong gluten, and good baking properties. ‘Bolles’ (PI 678430), a hard red spring wheat cultivar, was released by the University of Minnesota Agricultu...

  18. Screwing or unscrewing device for studs or bolls of big dimension

    International Nuclear Information System (INIS)

    Sevelinge, G.; Bourdonne, J.C.

    1988-01-01

    The device for screwing or unscrewing large studs or bolts has a system determining the optimun screwing position and orientation of the bolt, a variable speed bidirectional drive a pin holding the bolt axially and system compensating the weight of the bolt with an hydraulic jack with a pressure detector to which the drive is slaved [fr

  19. Variation in the Indian summer monsoon intensity during the Bolling-Allerod and Holocene

    Digital Repository Service at National Institute of Oceanography (India)

    Kessarkar, P.M.; Rao, V.P.; Naqvi, S.W.A.; Karapurkar, S.G.

    to PDB. Repetitive analysis of the NBS 18, 19 and internal laboratory standards revealed that analytical standard deviation was better than ±0.07‰. Total inorganic carbon (TIC) was determined using a coulometer. CaCO3 (%) was calculated... by multiplying TIC with factor of 8.333, the reproducibility was found to be better than 5 %. In order to estimate total organic carbon (Corg), total carbon was measured by CNS elemental analyser (NCS 2500) and Corg was derived from the difference between...

  20. Boll sampling protocols and their impact on measurements of cotton fiber quality

    Science.gov (United States)

    Within plant fiber variability has long contributed to product inconsistency in the cotton industry. Fiber quality uniformity is a primary plant breeding objective related to cotton commodity economic value. The physiological impact of source and sink relationships renders stress on the upper bran...

  1. Final Environmental Assessment: For Joint Base Anacostia-Bolling Master Plan District of Columbia

    Science.gov (United States)

    2010-09-30

    512 513 mil Mission I Admil’llslrative D moeld Ope<alloll$ CJ Logistics /Industrial 0 Open Spac:e I Recreation Naval Researc ~ Labohtory C...August 2009 a commuter 2033 ferry service is a viable option. It will undergo closer study in terms of market viability for certain 2034 stops in

  2. Energy efficiency assessment methods and tools evaluation. Bolling Air Force Base. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    McMordie, K.L.; Richman, E.E.; Keller, J.M.; Dixon, D.R.

    1995-05-01

    The goal of the U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP) is to facilitate energy-efficiency improvements at federal facilities. This is accomplished by a balanced program of technology development, facility assessment, and use of cost-sharing procurement mechanisms. Technology development focuses upon the tools, software, and procedures used to identify and evaluate energy-efficiency technologies and improvements. For facility assessment, FEMP provides metering equipment and trained analysts to federal agencies exhibiting a commitment to improve energy use efficiency. To assist in procurement of energy-efficiency measures, FEMP helps federal agencies devise and implement performance contracting and utility demand-side management strategies. Pacific Northwest Laboratory (PNL) supports the FEMP mission of energy systems modernization. Under this charter, the Laboratory and its contractors work with federal facility energy managers to assess and implement energy-efficiency improvements at federal facilities nationwide.

  3. 5 CFR 531.245 - Computing locality rates and special rates for GM employees.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Computing locality rates and special... Gm Employees § 531.245 Computing locality rates and special rates for GM employees. Locality rates and special rates are computed for GM employees in the same manner as locality rates and special rates...

  4. Energy reviews: the expense rate

    International Nuclear Information System (INIS)

    Chavanne, X.; Frangi, J.P.

    2008-01-01

    The threats against energy supplies push the prices of energy increasingly and lasting/ higher. Therefore it is important to establish the energy balance of an energy industry, which is more accurate than a too global financial balance. Life Cycle Analyses could be finely tuned using a method and tool suggested here: the T expense rate, the ratio between dissipated or spent energies, and extracted energy. T is a profitability indicator based on thermodynamics principles with 1 or 100 % as a theoretical limit. T is convenient too, because it can be broken down between the various steps or processes, and their D expenses. T also allows for a finely tuned analysis, to identify physical and technical parameters impacting the balance sheet. Uncertainties and arbitrary assumptions are explained, after having been boiled down to a minimum amount. A comparison between industries is thus possible for a given use (transportation, electrical production) depending on the form of energy extracted and the processes used. The energy balance is supplemented by the resource availability balance, different from the first one, even though availability may depend on it. (authors)

  5. Failure rate analysis using GLIMMIX

    International Nuclear Information System (INIS)

    Moore, L.M.; Hemphill, G.M.; Martz, H.F.

    1998-01-01

    This paper illustrates use of a recently developed SAS macro, GLIMMIX, for implementing an analysis suggested by Wolfinger and O'Connell (1993) in modeling failure count data with random as well as fixed factor effects. Interest in this software tool arose from consideration of modernizing the Failure Rate Analysis Code (FRAC), developed at Los Alamos National Laboratory in the early 1980's by Martz, Beckman and McInteer (1982). FRAC is a FORTRAN program developed to analyze Poisson distributed failure count data as a log-linear model, possibly with random as well as fixed effects. These statistical modeling assumptions are a special case of generalized linear mixed models, identified as GLMM in the current statistics literature. In the nearly 15 years since FRAC was developed, there have been considerable advances in computing capability, statistical methodology and available statistical software tools allowing worthwhile consideration of the tasks of modernizing FRAC. In this paper, the approaches to GLMM estimation implemented in GLIMMIX and in FRAC are described and a comparison of results for the two approaches is made with data on catastrophic time-dependent pump failures from a report by Martz and Whiteman (1984). Additionally, statistical and graphical model diagnostics are suggested and illustrated with the GLIMMIX analysis results

  6. Arrhenius Rate: constant volume burn

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-12-06

    A constant volume burn occurs for an idealized initial state in which a large volume of reactants at rest is suddenly raised to a high temperature and begins to burn. Due to the uniform spatial state, there is no fluid motion and no heat conduction. This reduces the time evolu tion to an ODE for the reaction progress variable. With an Arrhenius reaction rate, two characteristics of thermal ignition are illustrated: induction time and thermal runaway. The Frank-Kamenetskii approximation then leads to a simple expression for the adiabatic induction time. For a first order reaction, the analytic solution is derived and used to illustrate the effect of varying the activation temperature; in particular, on the induction time. In general, the ODE can be solved numerically. This is used to illustrate the effect of varying the reaction order. We note that for a first order reaction, the time evolution of the reaction progress variable has an exponential tail. In contrast, for a reaction order less than one, the reaction completes in a nite time. The reaction order also affects the induction time.

  7. Shapley ratings in brain networks

    Directory of Open Access Journals (Sweden)

    Rolf Kötter

    2007-11-01

    Full Text Available Recent applications of network theory to brain networks as well as the expanding empirical databases of brain architecture spawn an interest in novel techniques for analyzing connectivity patterns in the brain. Treating individual brain structures as nodes in a directed graph model permits the application of graph theoretical concepts to the analysis of these structures within their large-scale connectivity networks. In this paper, we explore the application of concepts from graph and game theory toward this end. Specifically, we utilize the Shapley value principle, which assigns a rank to players in a coalition based upon their individual contributions to the collective profit of that coalition, to assess the contributions of individual brain structures to the graph derived from the global connectivity network. We report Shapley values for variations of a prefrontal network, as well as for a visual cortical network, which had both been extensively investigated previously. This analysis highlights particular nodes as strong or weak contributors to global connectivity. To understand the nature of their contribution, we compare the Shapley values obtained from these networks and appropriate controls to other previously described nodal measures of structural connectivity. We find a strong correlation between Shapley values and both betweenness centrality and connection density. Moreover, a stepwise multiple linear regression analysis indicates that approximately 79% of the variance in Shapley values obtained from random networks can be explained by betweenness centrality alone. Finally, we investigate the effects of local lesions on the Shapley ratings, showing that the present networks have an immense structural resistance to degradation. We discuss our results highlighting the use of such measures for characterizing the organization and functional role of brain networks.

  8. Heart rate variability and swimming.

    Science.gov (United States)

    Koenig, Julian; Jarczok, Marc N; Wasner, Mieke; Hillecke, Thomas K; Thayer, Julian F

    2014-10-01

    Professionals in the domain of swimming have a strong interest in implementing research methods in evaluating and improving training methods to maximize athletic performance and competitive outcome. Heart rate variability (HRV) has gained attention in research on sport and exercise to assess autonomic nervous system activity underlying physical activity and sports performance. Studies on swimming and HRV are rare. This review aims to summarize the current evidence on the application of HRV in swimming research and draws implications for future research. A systematic search of databases (PubMed via MEDLINE, PSYNDEX and Embase) according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (a) empirical investigation (HRV) in humans (non-clinical); (b) related to swimming; (c) peer-reviewed journal; and (d) English language. The search revealed 194 studies (duplicates removed), of which the abstract was screened for eligibility. Fourteen studies meeting the inclusion criteria were included in the review. Included studies broadly fell into three classes: (1) control group designs to investigate between-subject differences (i.e. swimmers vs. non-swimmers, swimmers vs. other athletes); (2) repeated measures designs on within-subject differences of interventional studies measuring HRV to address different modalities of training or recovery; and (3) other studies, on the agreement of HRV with other measures. The feasibility and possibilities of HRV within this particular field of application are well documented within the existing literature. Future studies, focusing on translational approaches that transfer current evidence in general practice (i.e. training of athletes) are needed.

  9. 77 FR 36585 - Postal Rate Changes

    Science.gov (United States)

    2012-06-19

    ... Service notice of rate and changes affecting Inbound Air Parcel Post at Universal Postal Union (UPU) rates... United States Postal Service of Filing Changes in Rates Not of General Applicability and Application for... the Postal Service's explanation of Inbound Air Parcel Post (at UPU Rates) provided in the initial...

  10. Base Rates: Both Neglected and Intuitive

    Science.gov (United States)

    Pennycook, Gordon; Trippas, Dries; Handley, Simon J.; Thompson, Valerie A.

    2014-01-01

    Base-rate neglect refers to the tendency for people to underweight base-rate probabilities in favor of diagnostic information. It is commonly held that base-rate neglect occurs because effortful (Type 2) reasoning is required to process base-rate information, whereas diagnostic information is accessible to fast, intuitive (Type 1) processing…

  11. Dynamic half-rate connections in GSM

    NARCIS (Netherlands)

    Winands, E.M.M.; Wieland, J.; Sanders, B.

    2006-01-01

    Dynamic half-rate is an optional feature that allows a Global System for Mobile communication (GSM) cell to switch new incoming half-rate capable calls to half-rate speech coding, when the cell is nearly congested. Since two half-rate speech calls can be put together in one single-time slot, dynamic

  12. 24 CFR 206.21 - Interest rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Interest rate. 206.21 Section 206... CONVERSION MORTGAGE INSURANCE Eligibility; Endorsement Eligible Mortgages § 206.21 Interest rate. (a) Fixed interest rate. A fixed interest rate is agreed upon by the mortgagor and mortgagee. (b) Adjustable interest...

  13. 12 CFR 614.4155 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Interest rates. 614.4155 Section 614.4155 Banks... Policies for Banks and Associations § 614.4155 Interest rates. Loans made by each bank and direct lender association shall bear interest at a rate or rates as may be determined by the institution board. The board...

  14. 7 CFR 4280.124 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rates. 4280.124 Section 4280.124 Agriculture... Improvements Program Section B. Guaranteed Loans § 4280.124 Interest rates. (a) The interest rate for the... in similar circumstances in the ordinary course of business. The interest rate charged is subject to...

  15. 7 CFR 4274.325 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rates. 4274.325 Section 4274.325 Agriculture... (IRP) § 4274.325 Interest rates. (a) Loans made by the Agency pursuant to this subpart shall bear interest at a fixed rate of 1 percent per annum over the term of the loan. (b) Interest rates charged by...

  16. 7 CFR 1950.105 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Interest rate. 1950.105 Section 1950.105 Agriculture... rate. (a) The Soldiers and Sailors Relief Act requires that the effective interest rate charged a... Supervisor will send the borrower a letter which states that the interest rate on the borrower's FmHA or its...

  17. 7 CFR 1980.423 - Interest rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Interest rates. 1980.423 Section 1980.423 Agriculture... REGULATIONS (CONTINUED) GENERAL Business and Industrial Loan Program § 1980.423 Interest rates. (a) Guaranteed... variable as long as they are legal. Interest rates will be those rates customarily charged borrowers in...

  18. 48 CFR 942.704 - Billing rates.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION AND AUDIT SERVICES Indirect Cost Rates 942.704 Billing rates. (b) When the contracting officer or auditor responsible for establishing billing rates, in accordance with 48 CFR 42.704, has not established... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Billing rates. 942.704...

  19. 78 FR 62627 - Sam Rayburn Dam Rate

    Science.gov (United States)

    2013-10-22

    ..., Wholesale Rates for Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative, Inc. (Contract No... Schedule SRD-08, Wholesale Rates for Hydro Power and Energy Sold to Sam Rayburn Dam Electric Cooperative... ADMINISTRATION RATE SCHEDULE SRD-13 \\1\\ WHOLESALE RATES FOR HYDRO POWER AND ENERGY SOLD TO SAM RAYBURN DAM...

  20. 23 CFR 650.707 - Rating factor.

    Science.gov (United States)

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Rating factor. 650.707 Section 650.707 Highways FEDERAL..., STRUCTURES, AND HYDRAULICS Discretionary Bridge Candidate Rating Factor § 650.707 Rating factor. (a) The.... ER15OC02.010 The lower the rating factor, the higher the priority for selection and funding. (b) The terms...

  1. Factors influencing variation in dentist service rates.

    Science.gov (United States)

    Grembowski, D; Milgrom, P; Fiset, L

    1990-01-01

    In the previous article, we calculated dentist service rates for 200 general dentists based on a homogeneous, well-educated, upper-middle-class population of patients. Wide variations in the rates were detected. In this analysis, factors influencing variation in the rates were identified. Variation in rates for categories of dental services was explained by practice characteristics, patient exposure to fluoridated water supplies, and non-price competition in the dental market. Rates were greatest in large, busy practices in markets with high fees. Older practices consistently had lower rates across services. As a whole, these variables explained between 5 and 30 percent of the variation in the rates.

  2. Rate design in a competitive environment

    International Nuclear Information System (INIS)

    Wathen, J.M.

    1995-01-01

    Innovative rate designs used by several United States utilities to become more competitive, were presented. Considerations of retail wheeling and other services for increasing competitiveness were debated. The process for designing specialized rate programs was described, along with descriptions of special rate types, including economic development rates, load retention/anti-bypass rates, cogeneration/self-generation rates, distressed industry rates, load management rates and special situation rates. The existence of special provisions in state legislation allowing special rates to be offered was noted. Confidentiality and the need for a review process to ensure fairness of special agreements was discussed. The efficacy of using individual customer contracts to allow full recognition of the special characteristics and needs of individual customers and the effects of such contracts on the industry, were considered

  3. Corporate financing and anticipated credit rating changes

    OpenAIRE

    Hung, Chi-Hsiou D.; Banerjee, Anurag; Meng, Qingrui

    2017-01-01

    Firm circumstances change but rating agencies may not make timely revisions to their\\ud ratings, increasing information asymmetry between firms and the market. We examine\\ud whether firms time the securities market before a credit rating agency publicly reveals\\ud its decision to downgrade a firm's credit rating. Using quarterly data, we show that\\ud firms adjust their financing structures before credit rating downgrades are publicly\\ud revealed. More specifically, firms on average increase t...

  4. Exchange rate stabilization under imperfect credibility

    OpenAIRE

    Calvo, Guillermo; Vegh, Carlos

    1991-01-01

    This paper analyzes stabilization policy under predetermined exchange rates in a cash-in-advance, staggered-prices model. Under full credibility, a reduction in the rate of devaluation results in an immediate and permanent reduction in the inflation rate, with no effect on output or consumption. In contrast, a non-credible stabilization results in an initial expansion of output, followed by a later recession. The inflation rate of home goods remains above the rate of devaluation throughout...

  5. Exchange Rate Policy in Philippine Development

    OpenAIRE

    Bautista, Romeo M.

    2003-01-01

    This paper examines the conduct of exchange rate policy in the Philippines since the early 1980s, paying particular attention to the influence of exchange rate adjustments on relative production incentives. While primary interest is in the exchange rate regime and its incentive effects, the role of trade policy has to be simultaneously analyzed in view of its influence on the conduct of exchange rate policy as well as its direct effect on the real exchange rate. Moreover, there are analytical...

  6. Effective Exchange Rate Classifications and Growth

    OpenAIRE

    Justin M. Dubas; Byung-Joo Lee; Nelson C. Mark

    2005-01-01

    We propose an econometric procedure for obtaining de facto exchange rate regime classifications which we apply to study the relationship between exchange rate regimes and economic growth. Our classification method models the de jure regimes as outcomes of a multinomial logit choice problem conditional on the volatility of a country's effective exchange rate, a bilateral exchange rate and international reserves. An `effective' de facto exchange rate regime classification is then obtained by as...

  7. Intergenerational equity and the social discount rate

    OpenAIRE

    Scarborough, Helen

    2011-01-01

    Recent modelling of the costs and benefits of climate change has renewed debate regarding assumptions for the social discount rate in analysing the impacts of environmental change. Previous literature suggests two key factors influence estimates of the social discount rate: the rate of pure time preference and the elasticity of marginal utility of future consumption. These components of the social discount rate reinforce the linkages between the choice of social discount rate and intergenerat...

  8. 7 CFR 1714.5 - Determination of interest rates on municipal rate loans.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Determination of interest rates on municipal rate... General § 1714.5 Determination of interest rates on municipal rate loans. (a) RUS will post on the RUS website, Electric Program HomePage, a schedule of interest rates for municipal rate loans at the beginning...

  9. Mortality Rates Among Arab Americans in Michigan

    OpenAIRE

    Dallo, Florence J.; Schwartz, Kendra; Ruterbusch, Julie J.; Booza, Jason; Williams, David R.

    2012-01-01

    The objectives of this study were to: (1) calculate age-specific and age-adjusted cause-specific mortality rates for Arab Americans; and (2) compare these rates with those for blacks and whites. Mortality rates were estimated using Michigan death certificate data, an Arab surname and first name list, and 2000 U.S. Census data. Age-specific rates, age-adjusted all-cause and cause-specific rates were calculated. Arab Americans (75+) had higher mortality rates than whites and blacks. Among men, ...

  10. What does self rated mental health represent

    Directory of Open Access Journals (Sweden)

    Daphna Levinson

    2014-12-01

    Full Text Available Background. Unlike the widely used self rated health, the self rated mental health was found unsuitable as a proxy for mental illness. This paper analyses the relationships between the self ratings of physical health, mental health and overall health, and their association of with the objective indicators for physical and mental health. Design and methods. The study is a secondary analysis of data from a nationwide representative sample of the non-institutionalized adult residents of Israel in 2003 that was collected via computer-assisted personal interview methods [n=4859].Results. The self rated physical health and the self rated mental health were strongly related to each other yet the self rated mental health was not related to chronic physical conditions and the self rated physical health was not related to mental disorders. In a multiple logistic regression analysis, those with positive self rated mental health had 93 times the odds of reporting positive overall health whereas those with positive self rated physical health had 40 times the odds of reporting positive overall health. Conclusions. The self rating of mental health presents a qualitatively different dimension from mental illness. The self rated mental health is two times more important than the self rated physical health in predicting the self rated overall health

  11. Prostate Cancer Rates by Race and Ethnicity

    Science.gov (United States)

    ... HPV-Associated Lung Ovarian Skin Uterine Cancer Home Prostate Cancer Rates by Race and Ethnicity Language: English (US) ... Tweet Share Compartir The rate of men getting prostate cancer or dying from prostate cancer varies by race ...

  12. Rate type isotach compaction of consolidated sandstone

    NARCIS (Netherlands)

    Waal, J.A. de; Thienen-Visser, K. van; Pruiksma, J.P.

    2015-01-01

    Laboratory experiments on samples from a consolidated sandstone reservoir are presented that demonstrate rate type compaction behaviour similar to that observed on unconsolidated sands and soils. Such rate type behaviour can have large consequences for reservoir compaction, surface subsidence and

  13. 76 FR 48159 - Integrated System Power Rates

    Science.gov (United States)

    2011-08-08

    ... DEPARTMENT OF ENERGY Southwestern Power Administration Integrated System Power Rates AGENCY... American Electric Reliability Corporation and to cover increased investments and replacements in..., prepared a Current Power Repayment Study using existing system rates. The Study indicates that Southwestern...

  14. Colorectal Cancer Rates by Race and Ethnicity

    Science.gov (United States)

    ... Associated Lung Ovarian Prostate Skin Uterine Cancer Home Colorectal Cancer Rates by Race and Ethnicity Language: English (US) ... Tweet Share Compartir The rate of people getting colorectal cancer or dying from colorectal cancer varies by race ...

  15. Predicting Performance Ratings Using Motivational Antecedents

    National Research Council Canada - National Science Library

    Zazania, Michelle

    1998-01-01

    This research examined the role of motivation in predicting peer and trainer ratings of student performance and contrasted the relative importance of various antecedents for peer and trainer ratings...

  16. Stochastic interest rates model in compounding | Galadima ...

    African Journals Online (AJOL)

    Stochastic interest rates model in compounding. ... in finance, real estate, insurance, accounting and other areas of business administration. The assumption that future rates are fixed and known with certainty at the beginning of an investment, ...

  17. Mortality rates in people with intellectual disabilities

    Directory of Open Access Journals (Sweden)

    Rachael Williams

    2017-04-01

    National English data confirm that patients with ID have higher mortality rates than those without. Mortality rates for patients with ID were higher across all age/sex groups and causes, with almost half of deaths classified as avoidable.

  18. 77 FR 44571 - Rate Regulation Reforms

    Science.gov (United States)

    2012-07-30

    ... current T-bill rate to the U.S. Prime Rate, as published in The Wall Street Journal. Additional... ``exponential'' approach, the total cumulative reparations payment (including interest) is calculated by...

  19. National Marriage and Divorce Rate Trends

    Science.gov (United States)

    ... Vital Statistics Online National Death Index NCHS National Marriage and Divorce Rate Trends Recommend on Facebook Tweet Share Compartir Provisional number of marriages and marriage rate: United States, 2000-2014 Year ...

  20. Dose-rate dependence of thermoluminescence response

    International Nuclear Information System (INIS)

    McKeever, S.W.S.; Chen, R.; Groom, P.J.; Durrani, S.A.

    1980-01-01

    The previously observed dose-rate effect of thermoluminescence in quartz at high dose-rates is given at theoretical formulation. Computer calculations simulating the experimental conditions yield similar results to the experimental ones. (orig.)

  1. Measuring the costs of exchange rate volatility

    OpenAIRE

    Paul R. Bergin

    2004-01-01

    Many countries go to great lengths to manage their exchange rates. Probably the most prominent recent example is the European Monetary Union, where all the members abandoned their national currencies and adopted the euro. A number of developing countries maintain other kinds of regimes of managed exchange rates, even though they face potent market pressures to let their exchange rates float. One of the main motives for these arrangements stems from the extreme volatility of exchange rates. Th...

  2. Rate control for electron gun evaporation

    International Nuclear Information System (INIS)

    Schellingerhout, A.J.G.; Janocko, M.A.; Klapwijk, T.M.; Mooij, J.E.

    1989-01-01

    Principles for obtaining high-quality rate control for electron gun evaporation are discussed. The design criteria for rate controllers are derived from this analysis. Results are presented which have been obtained with e-guns whose evaporation rate is controlled by a Wehnelt electrode or by sweeping of the electron beam. Further improvements of rate stability can be obtained by improved design of e-guns and power supplies

  3. Cyclotron heating rate in a parabolic mirror

    International Nuclear Information System (INIS)

    Smith, P.K.

    1984-01-01

    Cyclotron resonance heating rates are found for a parabolic magnetic mirror. The equation of motion for perpendicular velocity is solved, including the radial magnetic field terms neglected in earlier papers. The expression for heating rate involves an infinite series of Anger's and Weber's functions, compared with a single term of the unrevised expression. The new results show an increase of heating rate compared with previous results. A simple expression is given for the ratio of the heating rates. (author)

  4. The Neutral Interest Rate: Estimates for Chile

    OpenAIRE

    Rodrigo Fuentes S; Fabián Gredig U.

    2008-01-01

    To estimate the neutral real interest rate for Chile, we use a variety of methods that can be classified into three categories: those derived from economic theory, the neutral rate implicit in financial assets, and statistical procedures using macroeconomic data. We conclude that the neutral rate is not constant over time, but it is closely related with—though not equivalent to—the potential GDP growth rate. The application of the different methods yields fairly similar results. The neutral r...

  5. Measuring Implicit Rental Rates for Farm Capital

    OpenAIRE

    Hrubovcak, James

    1986-01-01

    Developing implicit rental rates for capital inputs is an Important step in understanding the Impact of tax law changes on agricultural investments This article develops a methodology for estimating implicit rental rates and presents annual estimates of rental rates for seven categories of farm equipment and structures from 1955 to 1979 This article also compares these rental rates With those estimated under a no-tax alternative The author developed a method for estimating marginal Federal In...

  6. The local authority rating of independent generators

    International Nuclear Information System (INIS)

    Chapman, G.C.

    1991-01-01

    A brief history of the rating is given covering the public utilities. Formula rating of the nationalised electricity supply industry is described with independent generators' rates, the effect of privatisation and the longer term outlook considered. The need to convince the UK government that power generating machinery should no more be rated than any manufacturing or process machinery, and that all power producers should be treated the same is noted. (Author)

  7. Browse Title Index

    African Journals Online (AJOL)

    EE Akporhonor, IO Asia ... Vol 4, No 6 (2005):, The effect of spawn grains, culture media, oil types and rates on ... and nutrients digestibility in broilers fed with diet containing different levels of phosphorous, Abstract PDF ... involved in ethylene biosynthesis and signal perception during tomato flower abscission, Abstract PDF.

  8. Points of Interest: What Determines Interest Rates?

    Science.gov (United States)

    Schilling, Tim

    Interest rates can significantly influence people's behavior. When rates decline, homeowners rush to buy new homes and refinance old mortgages; automobile buyers scramble to buy new cars; the stock market soars, and people tend to feel more optimistic about the future. But even though individuals respond to changes in rates, they may not fully…

  9. Atmospheric production rate of {sup 36}Cl

    Energy Technology Data Exchange (ETDEWEB)

    Parrat, Y.; Hajdas, W.; Baltensperger, U.; Synal, H.A.; Kubik, P.W.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Suter, M. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    Using experimental cross sections, a new calculation of the atmospheric production rate of {sup 36}Cl was carried out. A mean production rate of 20 atoms m{sup -2}s{sup -1} was obtained, which is lower than mean {sup 36}Cl deposition rates. (author) 2 figs., 7 refs.

  10. Exchange rate policy under sovereign default risk

    OpenAIRE

    Schabert, Andreas

    2011-01-01

    We examine monetary policy options for a small open economy where sovereign default might occur due to intertemporal insolvency. Under interest rate policy and floating exchange rates the equilibrium is indetermined. Under a fixed exchange rate the equilibrium is uniquely determined and independent of sovereign default.

  11. 40 CFR 1033.140 - Rated power.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Rated power. 1033.140 Section 1033.140... EMISSIONS FROM LOCOMOTIVES Emission Standards and Related Requirements § 1033.140 Rated power. This section describes how to determine the rated power of a locomotive for the purposes of this part. (a) A locomotive...

  12. 76 FR 16570 - Interest Rate Risk

    Science.gov (United States)

    2011-03-24

    ... NATIONAL CREDIT UNION ADMINISTRATION 12 CFR Part 741 RIN 3133-AD66 Interest Rate Risk AGENCY... regulations to require Federally insured credit unions to have a written policy addressing interest rate risk... Risk Management for Credit Unions with Large Positions in Fixed Rate Mortgages; 06-CU-16 Inter-Agency...

  13. 12 CFR 563e.28 - Assigned ratings.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Assigned ratings. 563e.28 Section 563e.28 Banks... for Assessing Performance § 563e.28 Assigned ratings. (a) Ratings in general. Subject to paragraphs (b... performance under the lending, investment and service tests, the community development test, the small savings...

  14. Factors influencing HIV seroprevalence rate among pregnant ...

    African Journals Online (AJOL)

    Human immune deficiency virus (HIV) seroprevalence among pregnant women in Calabar was studied. The aims were to establish HIV seroprevalence rate and to identify factors which influence this rate in our pregnant women. HIV seroprevalence rate of 2.7% among antenatal women in Calabar was recorded with a ...

  15. Smoking, Discount Rates, and Returns to Education

    Science.gov (United States)

    Fersterer, Josef; Winter-Ebmer, Rudolf

    2003-01-01

    Individual time preference determines schooling enrolment. Moreover, smoking behavior in early ages has been shown to be highly related to time preference rates. Insofar as discount rates are uncorrelated to ability, predicting school enrolment by discount rates can get rid of the ability bias in an earnings regression. Accordingly, we use smoking…

  16. 18 CFR 704.39 - Discount rate.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Discount rate. 704.39... STANDARDS AND PROCEDURES Standards for Plan Formulation and Evaluation § 704.39 Discount rate. (a) The interest rate to be used in plan formulation and evaluation for discounting future benefits and computing...

  17. Currency crises and the interest rate defence

    NARCIS (Netherlands)

    Daniëls, T.

    2008-01-01

    While virtually all modern models of exchange rate crises recognise that the decision to abandon an exchange rate peg depends on how harshly policy makers are willing to defend the regime, they virtually never model how the exchange rate is defended. We argue that incorporating both the mechanics of

  18. Uncertain discount rates in climate policy analysis

    International Nuclear Information System (INIS)

    Newell, R.G.; Pizer, W.A.

    2004-01-01

    Consequences in the distant future - such as those from climate change--have little value today when discounted using conventional rates. This result contradicts our 'gut feeling' about such problems and often leads to ad hoc application of lower rates for valuations over longer horizons - a step facilitated by confusion and disagreement over the correct rate even over short horizons. We review the theory and intuition behind the choice of discount rates now and, importantly, the impact of likely variation in rates in the future. Correlated changes in future rates imply that the distant future should be discounted at much lower rates than suggested by the current rate, thereby raising the value of future consequences - regardless of opinions concerning the current rate. Using historic data to quantity the likely changes and correlation in changes in future rates, we find that future valuations rise by a factor of many thousands at horizons of 300 years or more, almost doubling the expected present value of climate mitigation benefits relative to constant 4% discounting. Ironically, uncertainty about future rates reduces the ratio of valuations based on alternate choices of the current rate

  19. 24 CFR 232.560 - Interest rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Interest rate. 232.560 Section 232... Equipment Eligible Security Instruments § 232.560 Interest rate. (a) The loan shall bear interest at the rate agreed upon by the lender and the borrower. (b) Interest shall be payable in monthly installments...

  20. 7 CFR 3550.66 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Interest rate. 3550.66 Section 3550.66 Agriculture... DIRECT SINGLE FAMILY HOUSING LOANS AND GRANTS Section 502 Origination § 3550.66 Interest rate. Loans will be written using the applicable RHS interest rate in effect at loan approval or loan closing...

  1. 24 CFR 200.83 - Interest rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Interest rate. 200.83 Section 200... Eligibility Requirements for Existing Projects Mortgage Provisions § 200.83 Interest rate. (a) The mortgage shall bear interest at the rate agreed upon by the mortgagee and the mortgagor. (b) Interest shall be...

  2. 8 CFR 293.2 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Interest rate. 293.2 Section 293.2 Aliens... CASH RECEIVED TO SECURE IMMIGRATION BONDS § 293.2 Interest rate. The Secretary of the Treasury has determined that effective from date of deposit occurring after April 27, 1966, the interest rate shall be 3...

  3. 5 CFR 1655.7 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Interest rate. 1655.7 Section 1655.7 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD LOAN PROGRAM § 1655.7 Interest rate. (a... interest rate established by the Department of the Treasury in effect on the date the TSP record keeper...

  4. 13 CFR 120.932 - Interest rate.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Interest rate. 120.932 Section 120.932 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) 504 Loans and Debentures § 120.932 Interest rate. The interest rate of the 504 Loan...

  5. 77 FR 65664 - Publication of Depreciation Rates

    Science.gov (United States)

    2012-10-30

    ... DEPARTMENT OF AGRICULTURE Rural Utilities Service Publication of Depreciation Rates AGENCY: Rural... announces the depreciation rates for telecommunications plant for the period ending December 31, 2011. DATES... Loans, Sec. 1737.70(e) explains the depreciation rates that are used by RUS in its feasibility studies...

  6. 76 FR 72672 - Publication of Depreciation Rates

    Science.gov (United States)

    2011-11-25

    ... DEPARTMENT OF AGRICULTURE Rural Utilities Service Publication of Depreciation Rates AGENCY: Rural... announces the depreciation rates for telecommunications plant for the period ending December 31, 2010. DATES..., Sec. 1737.70(e) explains the depreciation rates that are used by RUS in its feasibility studies. Sec...

  7. 76 FR 6762 - Publication of Depreciation Rates

    Science.gov (United States)

    2011-02-08

    ... DEPARTMENT OF AGRICULTURE Rural Utilities Service Publication of Depreciation Rates AGENCY: Rural... States Department of Agriculture (USDA), announces the depreciation rates for telecommunications plant...) explains the depreciation rates that are used by RUS in its feasibility studies. Sec. 1737.70(e)(2) refers...

  8. 7 CFR 25.104 - Poverty rate.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Poverty rate. 25.104 Section 25.104 Agriculture Office... § 25.104 Poverty rate. (a) General. Eligibility of an area on the basis of poverty shall be established in accordance with the following poverty rate criteria specific to Round I, Round II, Round IIS and...

  9. 24 CFR 597.103 - Poverty rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Poverty rate. 597.103 Section 597... Area Requirements § 597.103 Poverty rate. (a) General. The poverty rate shall be established in accordance with the following criteria: (1) In each census tract within a nominated urban area, the poverty...

  10. 24 CFR 598.115 - Poverty rate.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 3 2010-04-01 2010-04-01 false Poverty rate. 598.115 Section 598... Requirements § 598.115 Poverty rate. (a) General. In order to be eligible for designation, an area's poverty... poverty rate must be not less than 20 percent; and (2) For at least 90 percent of the census tracts within...

  11. Test Review: Autism Spectrum Rating Scales

    Science.gov (United States)

    Simek, Amber N.; Wahlberg, Andrea C.

    2011-01-01

    This article reviews Autism Spectrum Rating Scales (ASRS) which are designed to measure behaviors in children between the ages of 2 and 18 that are associated with disorders on the autism spectrum as rated by parents/caregivers and/or teachers. The rating scales include items related to behaviors associated with Autism, Asperger's Disorder, and…

  12. Have Floating Rates Been a Success?

    Science.gov (United States)

    Higham, David

    1983-01-01

    Floating exchange rates have not lived up to all expectations, but neither have they performed as badly as some critics have suggested. Examined are the impact of floating rates on balance of payments adjustment, domestic economic policy, and inflation and the claim that floating rates have displayed excessive fluctuations. (Author/RM)

  13. International convergence of capital market interest rates.

    NARCIS (Netherlands)

    Fase, M.M.G.; Vlaar, P.J.G.

    1997-01-01

    This article investigates the extent of capital market interest rate convergence among six EU countries on the one hand, and a group of four countries with floating exchange rates - US, Germany, Japan and Switzerland - on the other. We conclude that interest rate changes within the EU have been and

  14. The Deceptive Resilience of Fixed Exchange Rates

    OpenAIRE

    Mushin, Jerry

    2004-01-01

    This paper is an examination of the experience of exchange-rate systems since 1978. Despite the accelerating trend in favour of floating exchange rates, a substantial minority of IMF members have continued to fix the value of their currencies. The recent incidence of each of the principal types of exchange-rate peg is described.

  15. 7 CFR 1435.101 - Loan rates.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Loan rates. 1435.101 Section 1435.101 Agriculture... AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS SUGAR PROGRAM Sugar Loan Program § 1435.101 Loan rates. (a) The national average loan rate for raw cane sugar produced from domestically grown sugarcane is: 18...

  16. 33 CFR 159.69 - Motor ratings.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Motor ratings. 159.69 Section 159.69 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.69 Motor ratings. Motors must be rated...

  17. Exchange Rate and the PRC Foreign Trade

    Directory of Open Access Journals (Sweden)

    Izotov D. A.

    2009-09-01

    Full Text Available The stages of exchange rate regulation and foreign trade systems reforming in PRC during the period 1978-2008 are examined. A quantitative assessment of PRC foreign trade parameters reactions to the currency rate dynamics on the national and regional levels is made. Also the import and export impact of potential exchange rate changes is estimated

  18. Tabulated Neutron Emission Rates for Plutonium Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Shores, Erik Frederick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-24

    This work tabulates neutron emission rates for 80 plutonium oxide samples as reported in the literature. Plutonium-­238 and plutonium-­239 oxides are included and such emission rates are useful for scaling tallies from Monte Carlo simulations and estimating dose rates for health physics applications.

  19. 78 FR 25101 - Credit Ratings Roundtable

    Science.gov (United States)

    2013-04-29

    ... SECURITIES AND EXCHANGE COMMISSION [Release No. 34-69433; File No. 4-661] Credit Ratings... examine issues in connection with the possibility of developing a credit rating assignment system. The... FURTHER INFORMATION CONTACT: Scott Davey at (212) 336-0075, Office of Credit Ratings, Securities and...

  20. 5 CFR 430.308 - Rating performance.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Rating performance. 430.308 Section 430.308 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERFORMANCE MANAGEMENT Managing Senior Executive Performance § 430.308 Rating performance. (a) Initial summary rating...