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Academic literature on the topic 'Spread F'

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Published: 6 September 2023

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Journal articles on the topic "Spread F"

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MacDougall, J. W., M. A. Abdu, P. T. Jayachandran, J. F. Cecile, and I. S. Batista. "Presunrise spread F at Fortaleza." Journal of Geophysical Research: Space Physics 103, A10 (October 1, 1998): 23415–25. http://dx.doi.org/10.1029/98ja01949.

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Carrasco, A. J., I. S. Batista, J. H. A. Sobral, and M. A. Abdu. "Spread F modeling over Brazil." Journal of Atmospheric and Solar-Terrestrial Physics 161 (August 2017): 98–104. http://dx.doi.org/10.1016/j.jastp.2017.06.015.

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From, W. R., and D. H. Meehan. "Mid-latitude spread-F structure." Journal of Atmospheric and Terrestrial Physics 50, no. 7 (July 1988): 629–38. http://dx.doi.org/10.1016/0021-9169(88)90061-x.

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Tozer, T. C. "Spread-Spectrum Systems." IEE Proceedings F Communications, Radar and Signal Processing 133, no. 1 (1986): 128. http://dx.doi.org/10.1049/ip-f-1.1986.0020.

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de Boorder, J. "Spread of F gigantica in Tanzania." Veterinary Record 131, no. 8 (August 22, 1992): 180. http://dx.doi.org/10.1136/vr.131.8.180.

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Wright, J. W. "Quantifying spread F by digital ionosondes." Advances in Space Research 31, no. 3 (January 2003): 729–34. http://dx.doi.org/10.1016/s0273-1177(03)00046-2.

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Becker-Guedes, F., Y. Sahai, P. R. Fagundes, W. L. C. Lima, V. G. Pillat, J. R. Abalde, and J. A. Bittencourt. "Geomagnetic storm and equatorial spread-F." Annales Geophysicae 22, no. 9 (September 23, 2004): 3231–39. http://dx.doi.org/10.5194/angeo-22-3231-2004.

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Abstract. In August 2000, a new ionospheric sounding station was established at Sao Jose dos Campos (23.2° S, 45.9° W; dip latitude 17.6° S), Brazil, by the University of Vale do Paraiba (UNIVAP). Another ionospheric sounding station was established at Palmas (10.2° S, 48.2° W; dip latitude 5.5° S), Brazil, in April 2002, by UNIVAP in collaboration with the Lutheran University Center of Palmas (CEULP), Lutheran University of Brazil (ULBRA). Both the stations are equipped with digital ionosonde of the type known as Canadian Advanced Digital Ionosonde (CADI). In order to study the effects of geomagnetic storms on equatorial spread-F, we present and discuss three case studies, two from the ionospheric sounding observations at Sao Jose dos Campos (September and November 2000) and one from the simultaneous ionospheric sounding observations at Sao Jose dos Campos and Palmas (July 2003). Salient features from these ionospheric observations are presented and discussed in this paper. It has been observed that sometimes (e.g. 4-5 November 2000) the geomagnetic storm acts as an inhibitor (high strong spread-F season), whereas at other times (e.g. 11-12 July 2003) they act as an initiator (low strong spread-F season), possibly due to corresponding changes in the quiet and disturbed drift patterns during different seasons.
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Alex, S., P. V. Koparkar, and R. G. Rastogi. "Spread-F and ionization anomaly belt." Journal of Atmospheric and Terrestrial Physics 51, no. 5 (May 1989): 371–79. http://dx.doi.org/10.1016/0021-9169(89)90119-0.

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Chandra, H., G. D. Vyas, H. S. S. Sinha, S. Prakash, and R. N. Misra. "Equatorial spread-F campaign over SHAR." Journal of Atmospheric and Solar-Terrestrial Physics 59, no. 2 (January 1997): 191–205. http://dx.doi.org/10.1016/1364-6826(95)00199-9.

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Jung, Hye-Young, Woo-Joo Lee, and Seung Hoe Choi. "Hybrid Fuzzy Regression Analysis Using the F-Transform." Applied Sciences 10, no. 19 (September 25, 2020): 6726. http://dx.doi.org/10.3390/app10196726.

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This paper proposes a hybrid estimation algorithm for independently estimating the response function for the center and the response function for the spread in fuzzy regression model. The proposed algorithm combines the least absolute deviations estimation with discriminant analysis. In addition, the F-transform is used to convert spreads of the dependent variable into several groups. Two examples show that our method is superior to the existing methods based on the fuzzy regression model that assumes the same function for spread and center.
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Dissertations / Theses on the topic "Spread F"

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Chapagain, Narayan P. "Dynamics of Equatorial Spread F Using Ground-Based Optical and Radar Measurements." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/897.

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The Earth's equatorial ionosphere most often shows the occurrence of large plasma density and velocity fluctuations with a broad range of scale sizes and amplitudes. These night time ionospheric irregularities in the F-region are commonly referred to as equatorial spread F (ESF) or plasma bubbles (EPBs). This dissertation focuses on analysis of ground-based optical and radar measurements to investigate the development and dynamics of ESF, which can significantly disrupt radio communication and GPS navigation systems. OI (630.0 nm) airglow image data were obtained by the Utah State University all-sky CCD camera, primarily during the equinox period, from three different longitudinal sectors under similar solar flux conditions: Christmas Island in the Central Pacific Ocean, Ascension Island in South Atlantic, and Brasilia and Cariri in Brazil. Well-defined magnetic field-aligned depletions were observed from each of these sites enabling detailed measurements of their morphology and dynamics. These data have also been used to investigate day-to-day and longitudinal variations in the evolution and distribution of the plasma bubbles, and their nocturnal zonal drift velocities. In particular, comparative optical measurements at different longitudinal sectors illustrated interesting findings. During the post midnight period, the data from Christmas Island consistently showed nearly constant eastward bubble velocity at a much higher value (~80 m/s) than expected, while data from Ascension Island exhibited a most unusual shear motion of the bubble structure, up to 55 m/s, on one occasion with westward drift at low latitude and eastward at higher latitudes, evident within the field of view of the camera. In addition, long-term radar observations during 1996-2006 from Jicamarca, Peru have been used to study the climatology of post-sunset ESF irregularities. Results showed that the spread F onset times did not change much with solar flux and that their onset heights increased linearly from solar minimum to solar maximum. On average, radar plume onset occurred earlier with increasing solar flux, and plume onset and peak altitudes increased with solar activity. The F-region upward drift velocities that precede spread F onset increased from solar minimum to solar maximum, and were approximately proportional to the maximum prereversal drift peak velocities.
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Pelon, Floriane. "Fibroblastic heterogeneity and metastatic spread in breast cancers Fibroblast heterogeneity drives metastatic spread in breast cancer through distinct mechanisms." Thesis, Sorbonne Paris Cité, 2018. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=2392&f=17330.

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Les cancers du sein, premiers cancers féminins et causes aujourd’hui encore de nombreux décès, sont classés en 3 sous-types moléculaires : luminaux –les plus répandus, HER2 et triple-négatifs (TN) –les plus agressifs. Lors du diagnostic, l’envahissement des ganglions lymphatiques axillaires par les cellules tumorales est établi. Il s’agit, en plus de la classification moléculaire, d’un marqueur pronostique utilisé en clinique pour stratifier les patientes, car il informe sur le risque de développement ultérieur de métastases, cause majeure des décès à l’heure actuelle. Les tumeurs solides, et notamment les cancers du sein, sont des écosystèmes complexes comprenant de nombreux types cellulaires qui interagissent avec les cellules cancéreuses. Parmi eux, les fibroblastes associés au cancer (CAF) sont les plus abondants et participent activement à de nombreux aspects de la tumorigenèse dont la croissance, l’invasion, l’angiogenèse, l’immunosuppression. Cependant, ils constituent une population hétérogène et à ce jour, très peu d’études ont analysé cette hétérogénéité tout en la liant aux diverses fonctions décrites des CAF. Dans ce projet, nous nous sommes intéressés au rôle de cette hétérogénéité fibroblastique dans la dissémination métastatique des cancers du sein. En combinant l’étude de plusieurs marqueurs de CAF, nous avons montré que les ganglions lymphatiques envahis par les cellules tumorales sont constitués de 4 sous-populations de CAF (CAF-S1, S2, S3 et S4), similaires à celles identifiées dans les tumeurs primaires appariées. De façon intéressante, ce sont les deux sous-types de CAF myofibroblastiques (αSMA+), CAF-S1 et particulièrement CAF-S4, qui s’accumulent préférentiellement dans les ganglions métastatiques. Ils présentent les mêmes signatures transcriptomiques entre les deux localisations tissulaires (ganglions envahis et tumeurs primaires correspondantes). Or, ces deux populations CAF-S1 et CAF-S4 augmentent le phénotype invasif des cellules tumorales, en régulant des fonctions complémentaires. D’un côté, les CAF-S1 sont hautement motiles, et stimulent la prolifération, la migration, l’invasion et l’initiation d’une transition épithélio-mésenchymateuse des cellules de cancer du sein. De l’autre, les CAF-S4 sont très contractiles, capables de remodeler la matrice extracellulaire et promeuvent ainsi l’invasion et la motilité des cellules tumorales dans des systèmes en 3 dimensions. Des expériences fonctionnelles suggèrent que l’action des CAF-S1 implique CXCL12 et TGFβ tandis que celle des CAF-S4 dépend de la voie NOTCH. En accord avec ces résultats, l’accumulation des CAF et leur identité dans les ganglions envahis constituent deux nouveaux facteurs pronostics dans les cancers du sein, indépendants du sous-type de cancers du sein et de l’envahissement ganglionnaire. En effet, un fort contenu en CAF-S4 y est associé avec un développement ultérieur de métastases à longue distance. Ainsi, analyser le contenu fibroblastique des ganglions axillaires au diagnostic pourrait constituer une information nouvelle et utile à la prise en charge des patientes
Breast cancers are the most common cancers in women and despite great improvements in treatments, they are still responsible for many deaths worldwide. They are classified into 3 main molecular subtypes: Luminal cancers are the most frequent ones, while HER2 and TN are the most aggressive. At diagnostic, lymph node involvement is also assessed as it constitutes, in addition to molecular classification, a strong prognostic marker. Indeed, it informs on the risk to develop further distant metastases, which is the main cause of death by cancer. Solid tumors, including breast cancers, are complex ecologies comprising numerous different cell types that interact with cancer cells. Among them, cancer-associated-fibroblasts (CAF) are the most abundant and actively participate in many tumor hallmarks such as tumor growth, invasion, immunosuppression and angiogenesis. However, they do not constitute a homogeneous population but so far, only few studies have characterized this heterogeneity and linked it to CAF previously described functions. In this project, we focused on the potential involvement of CAF heterogeneity in breast cancer metastatic spread. Combining the analysis of several CAF markers, we showed that invaded LN comprise 4 CAF subsets (CAF-S1, S2, S3 and S4), similar to those found in primary tumors. Interestingly, the two myofibroblastic subsets (αSMA+) CAF-S1 and especially CAF-S4 preferentially accumulate in metastatic LN and present the same transcriptomic profiles in both tumors and LN. Importantly, both CAF-S1 and CAF-S4 display pro-invasive properties, by acting at different levels on tumor cells. On the one hand, highly motile CAF-S1 stimulate breast cancer cell proliferation, migration and EMT initiation. On the other hand, CAF-S4 exhibit an important contractility and by remodeling the matrix they are able to promote tumor cell invasion in 3D. Functional studies highlight a CXCL12/TGFβ involvement in CAF-S1 functions while CAF-S4 pro-invasive phenotype appears to be Notch-dependent. In agreement with these data, we found that CAF accumulation and subset enrichment in involved LN were two new prognostic factors, independent of breast cancer molecular subtypes and LN status at diagnosis. Indeed, stromal rich LN with a predominance of CAF-S4 are associated with long distance metastases development and poor overall survival. Thus, we propose that analyzing LN fibroblastic content at diagnosis could constitute new and useful information to breast cancer patients’ care
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Paradza, Masimba Wellington. "Development of a neural network based model for predicting the occurrence of spread F within the Brazilian sector." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1005245.

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Spread F is a phenomenon of the ionosphere in which the pulses returned from the ionosphere are of a much greater duration than the transmitted ones. The occurrence of spread F can be predicted using the technique of Neural Networks (NNs). This thesis presents the development and evaluation of NN based models (two single station models and a regional model) for predicting the occurrence of spread F over selected stations within the Brazilian sector. The input space for the NNs included the day number (seasonal variation), hour (diurnal variation), sunspot number (measure of the solar activity), magnetic index (measure of the magnetic activity) and magnetic position (latitude, magnetic declination and inclination). Twelve years of spread F data measured during 1978 to 1989 inclusively at the equatorial site Fortaleza and low latitude site Cachoeira Paulista are used in the development of an input space and NN architecture for the NN models. Spread F data that is believed to be related to plasma bubble developments (range spread F) were used in the development of the models while those associated with narrow spectrum irregularities that occur near the F layer (frequency spread F) were excluded. The results of the models show the dependency of the probability of spread F as a function of local time, season and latitude. The models also illustrate some characteristics of spread F such as the onset and peak occurrence of spread F as a function of distance from the equator. Results from these models are presented in this thesis and compared to measured data and to modelled data obtained with an empirical model developed for the same purpose.
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Küsgen, Jörg. "Entwicklung von Kreditrisikopreisen und externen Ratings : eine systematische Überblicksanalyse /." Hamburg : Diplomica Verl, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=015791521&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Wolff, Jürgen. "Eine Intermarket-Analyse der Komponenten der Geld-Brief-Spanne : am Beispiel des deutschen Aktienmarktes /." Wiesbaden : Dt. Univ.-Verl, 2003. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016960607&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Küster-Simić, André. "Orderbuchtransparenz, Bietverhalten und Liquidität /." Wiesbaden : Dt. Univ.-Verl, 2001. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=009498556&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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Thompson, G. "The Effects of Navel Orange Prorate Suspension on F. O. B. to Retail Price Spreads." College of Agriculture, University of Arizona (Tucson, AZ), 1988. http://hdl.handle.net/10150/215711.

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The effects of the navel orange prorate suspension on packinghouse to retail price spreads are analyzed When compared with price spreads for the 1986 season, F.o.b.-retail price spreads declined for Atlanta and San Francisco, but increased for Dallas.
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Hjertberg, Jenny. ""Ja fast fler sanningar kontra att försöka sprida ett budskap det är ju två olika saker tycker jag" : En studie om lågstadielärares historieförståelse." Thesis, Högskolan Dalarna, Pedagogiskt arbete, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:du-24019.

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Syftet med den här studien var att synliggöra F-3 lärares historieförståelse. Ambitionen med detta synliggörande var att bidra med en fördjupad insikt om potentialen av F-3 lärares historieförståelse vad gäller möjligheter att främja elevers tolerans och kritiska förmåga. Studiens syfte och frågeställningar besvarades med hjälp av kvalitativ metod i form av intervjuer med F-3 lärare som undervisar i historia. Data analyserades med inspiration av en fenomenografisk ansats och med teorier om en historieförståelse utifrån perspektivets och sammanhangets betydelse och Rüsens typologi om olika funktioner av berättande. Resultatet tyder på att hälften av de studerade lärarna har en traditionell historieförståelse, vilket betyder att historia framställs som något faktiskt och statiskt. Resterande lärare kan relateras till en genetisk historieförståelse, vilket betyder att historia betraktas utifrån flera perspektiv och sammanhang. Med en sådan historieförståelse är det möjligt att främja elevers tolerans och kritiska tänkande då flera förståelser framhävs. Detta talar för att låta elever möta historia som utgår från en genetisk förståelse redan i lågstadiet, eftersom det är i grundskolans tidigare år som grunden för all utveckling läggs.

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Costa, Juliana Nascimento da. "Estudo da estabilidade de maracujà (Passiflora edulis Sims f. flavicarpa degener) em pÃ, proveniente de cultivo orgÃnico." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8523.

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FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico
O maracujà à um fruto originÃrio da AmÃrica Tropical, sendo cultivado em paÃses de climas tropical e subtropical, pertencente à famÃlia Passifloraceae, gÃnero Passiflora. O Brasil à o maior produtor mundial de maracujÃ, sendo o maracujÃ-amarelo ou azedo, o mais cultivado, tendo sua produÃÃo voltada ao consumo in natura e à industrializaÃÃo. Dentre os mÃtodos de cultivo do maracujÃ, tem-se a produÃÃo pelo sistema orgÃnico, ainda incipiente no Brasil, no entanto, jà existe grande demanda, principalmente no mercado Europeu, se tornando uma prÃtica cada vez mais comum, visando aliar qualidade de produtos alimentÃcios com a preservaÃÃo ambiental. O MaracujÃ-amarelo à muito apreciado na alimentaÃÃo humana pelo seu sabor intenso e aroma exÃtico, no entanto, a sua elevada perecibilidade dificulta o aumento da vida pÃs-colheita e armazenamento in natura dos frutos. Considerando as tendÃncias atuais por alimentos nutritivos e de rÃpido preparo, a sua utilizaÃÃo sob a forma desidratada, consiste em uma interessante alternativa para a reduÃÃo de perdas, agregar valor ao produto e proporcionar outras maneiras de consumo da fruta. Com base nessas informaÃÃes, o objetivo do trabalho à avaliar a estabilidade do pà de maracujà amarelo, proveniente de cultivo orgÃnico, obtido por spray drying, durante armazenamento por 360 dias, sob temperatura ambiente (Â25ÂC), caracterizando-o quanto aos aspectos fÃsico-quÃmicos, quÃmicos e microbiolÃgicos, acompanhando assim a qualidade desse produto ao longo de sua vida de prateleira. O produto em pà orgÃnico foi cedido por uma empresa processadora de frutos, localizada em Ubajara/CE. ApÃs o processamento as amostras foram levadas para o LaboratÃrio de Frutos e HortaliÃas e Microbiologia de Alimentos do DTA/CCA/UFC em Fortaleza, CE, onde foram mantidas à temperatura ambiente (Â25ÂC) durante os procedimentos analÃticos. Os pÃs de maracujà foram avaliados a cada 30 dias, durante 360 dias de armazenamento, quanto aos seguintes parÃmetros: pH, sÃlidos solÃveis, acidez titulÃvel, SS/AT, atividade de Ãgua, umidade, cinzas, higroscopicidade, solubilidade, aÃÃcares solÃveis totais, aÃÃcares redutores, coordenadas de cor L* a*, b*, croma (c*) e hue ( h*), flavonÃides-amarelos, polifenÃis extraÃveis totais, clorofila total, Ãcido ascÃrbico e β-caroteno. O pà de maracujà orgÃnico manteve-se praticamente estÃvel durante os 360 dias de armazenamento, sob temperatura ambiente (Â25ÂC), oferecendo um grande potencial de utilizaÃÃo, por apresentar adequada retenÃÃo de Ãcido ascÃrbico, higroscopicidade desejada, baixa atividade de Ãgua, pH Ãcido estÃvel, altos teores de cinzas, aÃÃcares, polifenÃis extraÃveis totais e resultados microbiolÃgicos satisfatÃrios, estando o produto sob Ãtimas condiÃÃes higiÃnico-sanitÃrias, apto para o consumo humano.
Passion fruit is a fruit which originates from Tropical America, is cultivated in countries with tropical and subtropical climates, and belongs to the Passifloracea family and Passiflora genus. Brazil is the largest producer of passion fruit in the world, and yellow or sour passion fruit is the most cultivated. Its production has focused on in natura consumption and industrialization. Among the methods of cultivation of passion fruit, the organic production system stands out. It is still incipient in Brazil, but there is great demand, especially in the European market, as it is becoming a common practice in order to combine food quality with environmental preservation. The yellow passion fruit is highly appreciated for the intense flavor and exotic aroma of this fruit, but it has high perishability which makes it difficult to increase the postharvest life and storage of in natura fruits. Considering the current trends in nutritional foods, which canbe prepared quickly their use in dehydrated form is an interesting alternative to reduce losses, add value to the product and provide other ways consume the fruit. Based on this information, the study aims to evaluate the stability of the passion fruit powder from organic cultivation, obtained by spray drying, during 360 days of storage at room temperature (Â25ÂC), characterizing it as to the physical-chemical, chemical and microbiological aspects, monitoring the quality of the product throughout its shelf life. The organic powder product was obtained from a fruit processing company, located in Ubajara, Ceara, north-east Brazil. After processing, the samples were taken to the Fruits and Vegetables Laboratory and to Food Microbiology Laboratory of DTA/CCA/UFC in Fortaleza, where they were kept at room temperature (Â25ÂC) during the analytical procedures. The passion fruit powder was evaluated every 30 days during 360 days of storage, for the following parameters: pH, soluble solids, titratable acidity, SS/AT, water activity, moisture, ash, hygroscopicity, solubility, soluble sugars, reducers sugars, color coordinates L*, a*, b*, chroma (c*) and Hue (H*), total anthocyanins, yellow flavonoids, total extractable polyphenols, total chlorophyll, ascorbic acid and β-carotene. The passion fruit powder remained stable during 360 days of storage at room temperature (Â25ÂC), offering a great potential for use. It presented adequate retention of ascorbic acid, hygroscopicity desired, low water activity, acid pH stable, high levels of ash, sugars, total extractable polyphenols and satisfactory microbiological result so that the product was in optimum hygienic and sanitary condition, fit for human consumption.
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Sepret, Virginie. "Application de la PIV sur traceurs fluorescents à l'étude de l'entraînement d'air par un spray Diesel. Influence de la densité ambiante et du diamètre de trou d'injecteur." Thesis, Toulouse, INPT, 2009. http://www.theses.fr/2009INPT015H/document.

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Le développement actuel des moteurs doit répondre à une volonté de réduction de la consommation et à des normes de plus en plus sévères. Les moteurs Diesel, bien que performants, présentent des émissions trop importantes d'oxydes d'azote (NOx) et de particules de suies. Ces émissions polluantes proviennent essentiellement de l'existence de zones riches en carburant ne permettant pas une combustion optimale. La préparation du mélange air / carburant, fortement conditionné par l'entraînement d'air par le spray est donc essentielle. La Vélocimétrie par Images de Particules sur traceurs Fluorescents, associée à un traitement spécifique des champs de vitesses instantanés de la phase gazeuse externe sont utilisés afin d'obtenir des mesures en proche frontière du spray. Dans la zone quasi statique du spray, un effet important de la densité ambiante sur le taux de mélange est mis en évidence. D'autre part, la diminution du diamètre de trou d'injecteur améliore sensiblement le taux de mélange local. Pour compléter cette analyse, un gain du taux de mélange entre les deux injecteurs est calculé pour chaque densité ambiante. Pour les fortes densités, le gain issu de la réduction du diamètre de trou peut at! teindre une valeur importante (> 60%). La phase gazeuse latérale dans la zone instationnaire du spray est ensuite investiguée et la méthodologie de la F-PIV est transposée à cette zone. Un lien entre la longueur de pénétration du spray et des longueurs d'entraînement est défini. La densité ambiante n'a pas d'effet sur ces longueurs d'entraînement. La diminution du diamètre de trou engendre une augmentation du gaz entraîné à une distance plus courte du nez de l'injecteur. Cependant, cette étude montre que les deux sprays n'engendrent pas un entraînement de gaz similaire
The actual development of the engine must reply to a will of fuel consumption reduction and to stricter norms concerning the pollutant emissions. Although the Diesel engines are competitive, the NOx and soot particle emissions mainly come from the existence of wealthy fuel zone preventing an optimal combustion. Therefore, the air / fuel mixing preparation, highly controlled by the air entrainment in spray, is essential. Particle Image Velocimetry on fluorescent tracers, associated with a specific processing of the instantaneous velocity fields have been applied to obtain measurements in the near vicinity of the spray edge. In the "quasi- teady" region of the spray, the important effect of the ambient density on the mixing rate has been pointed out. On the other hand, an orifice diameter decrease significantly improves the local air / fuel ratio. To complete this analyse, a gain in mixing rate between two different injectors has! been calculated for each gas density. For high densities, the gain due to a reduction of the hole diameter can reach important value (> 60%). Then, lateral gaseous phase in no stationary zone of spray is studying and F-PIV method is transposed to this zone. A link between the penetration length and entrainment lengths is defined. Ambient density has not effect on entrainment lengths. The hole diameter decrease generates entrained gas increase at shorter distance of injector nozzle. However, this study shows two sprays do not generated the same gas entrainment
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Books on the topic "Spread F"

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Calvert, Wynne. Equatorial Spread F; NBS Technical Note 145. Hassell Street Press, 2021.

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Golf, John. F*cking Spread of Disease: Swear Words Coloring and Activity Book for Teens and Adults with 30 Pictures of Foul Mouths of VIRUS in Size 8. 5x11 Inches Page Each. Independently Published, 2020.

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Press, What The Fork, and What The Fork Press Weekly Meal Plans. What the Fork Should I Make for Dinner Weekly Meal Planner for 52 Weeks: Funny What the F**k Menu Planner 2 Full Page Spread for each Week, Breakfast, ... Notes, Funny & Practical Gag Gift , 8 x 10. CreateSpace Independent Publishing Platform, 2018.

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Parkinson, Michael, John P. Dalton, and Sandra M. O’Neill. Fasciolosis. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780198570028.003.0079.

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Liver fluke disease, or fasciolosis, of livestock and humans is caused by endoparasitic trematodes of the genus Fasciola. Fasciola hepatica is responsible for the disease in temperate climates whereas F. gigantica is found in tropical zones. Recently, hybrids between F. hepatica and F. gigantica have been described (Le et al. 2008, Periago et al. 2008). Fasciolosis is a true zoonoses as it is predominantly a disease of animals that can be transmitted to humans at a specific stage of the parasite’s complex life cycle. There are a number of definitive hosts which includes sheep, cattle, and humans but this parasite has evolved to infect many other mammalian hosts including pigs, dogs, alpacas, llamas, rats, and goats (Apt et al. 1993; Chen and Mott 1990; Esteban et al. 1998). While prevalence of infection in humans may be relatively low in relation to animals, in specific geographic locations, for example in Bolivia, the prevalence of fasciolosis is so high in the human populations (hyperendemic) that it contributes to the spread of disease in animals (Esteban et al. 1999; Mas-Coma et al. 1999).Archeological studies showing Fasciola eggs in ancient mummies in Egypt demonstrate that fasciolosis is an ancient human disease (David 1997). Sporadic cases of fasciolosis were reported in Egypt in 1958 (Kuntz et al. 1958). The first to carry out an extensive review on human fasciolosis were Chen and Mott (1990). They reported 2,595 cases in over 40 countries in Europe, the Americas, Asia, Africa and the western Pacifi c from 1970 – 1990. This review raised awareness of fasciolosis in humans and triggered a growth in epidemiological studies and a consequential dramatic increase in reporting of cases in the literature. Now human fasciolosis is recognized by the World Health Organization (WHO) as an important disease in humans with an estimated 2.4 million people infected annually and 180 million at risk to infection in over 61 countries (Haseeb et al. 2002). There have been several cases of large scale epidemics in France (Dauchy et al. 2007), Egypt (Curtale et al. 2007) and Iran (Rokni et al. 2002).However, the only extensive epidemiological studies to determine the rate of infection have been carried out in Egypt and Bolivia (Curtale et al. 2003, 2007; Esteban et al. 2002; Parkinson et al. 2007). These studies have shown that co-infection with other diseases is a common occurrence and this may lead to under-reporting of the incidence of fasciolosis (Esteban et al. 2003; Maiga et al. 1991). In many countries, the overall rates of infection are extrapolated from sporadic reports of the disease and, consequently, worldwide disease prevalence is uncertain. In this chapter we will review the cause and effect of human fasciolosis, and particularly highlight important considerations in designing control strategies to reduce infection in at-risk communities.
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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Journale, Papierschule Planer. Planer 2020 Januar - Dezember: Ein Monats- und Wochenplaner Ab Dem 1. Januar Bis 31. Dezember 2020, der Die Kalender F�r 2019, 2020, 2021, 12 Monatskalender Spreads und 53 Wochen Spreads Umfasst. Independently Published, 2019.

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Book chapters on the topic "Spread F"

1

Novak, Robert, and Witold A. Krzymień. "Packet Re-Transmission Options for the SS-OFDM-F/TA System." In Multi-Carrier Spread-Spectrum, 89–100. Dordrecht: Springer Netherlands, 2004. http://dx.doi.org/10.1007/978-94-017-0502-8_11.

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Huba, J. D., G. Joyce, and J. Krall. "Three-Dimensional Modeling of Equatorial Spread F." In Aeronomy of the Earth's Atmosphere and Ionosphere, 211–18. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-0326-1_15.

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Novak, R., and W. A. Krzymien. "A Downlink SS-OFDM-F/TA Packet Data System Employing Multi-User Diversity." In Multi-Carrier Spread-Spectrum & Related Topics, 181–90. Boston, MA: Springer US, 2002. http://dx.doi.org/10.1007/978-1-4757-3569-7_19.

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Abdu, Mangalathayil Ali, and E. Alam Kherani. "Coupling Processes in the Equatorial Spread F/Plasma Bubble Irregularity Development." In Aeronomy of the Earth's Atmosphere and Ionosphere, 219–38. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-0326-1_16.

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Sekar, R., and D. Chakrabarty. "A Review of the Recent Advances in the Investigation of Equatorial Spread F and Space Weather Effects over Indian Sector Using Optical and Other Techniques." In Aeronomy of the Earth's Atmosphere and Ionosphere, 251–68. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-94-007-0326-1_18.

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Bussmann, Rainer W., Narel Y. Paniagua-Zambrana, and Grace N. Njoroge. "Lippia javanica (Burm. f.) Spreng. Verbenaceae." In Ethnobotany of the Mountain Regions of Africa, 1–5. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-77086-4_102-1.

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Bussmann, Rainer W., Narel Y. Paniagua-Zambrana, and Grace N. Njoroge. "Lippia javanica (Burm. f.) Spreng. Verbenaceae." In Ethnobotany of the Mountain Regions of Africa, 667–71. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-38386-2_102.

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Ikhmayies, Shadia J. "Characterization of Nanocrystalline SnO2:F Thin Films Prepared by the Spray Pyrolysis Technique." In T.T. Chen Honorary Symposium on Hydrometallurgy, Electrometallurgy and Materials Characterization, 508–22. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118364833.ch46.

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Ikhmayies, Shadia J. "Thickness Dependence of the Optical Parameters of Spray-Deposited SnO2: F Thin Films." In TMS2015 Supplemental Proceedings, 593–600. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2015. http://dx.doi.org/10.1002/9781119093466.ch74.

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Ikhmayies, Shadia J. "Thickness Dependence of the Optical Parameters of Spray-Deposited SnO2:F Thin Films." In TMS 2015 144th Annual Meeting & Exhibition, 593–600. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-48127-2_74.

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Conference papers on the topic "Spread F"

1

Onwumechili, C. Agedi. "Spread F phenomenon." In Basic space science. AIP, 1992. http://dx.doi.org/10.1063/1.41726.

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Deosarkar, S. B., T. R. Sontakke, and A. B. Nandgaonkar. "Assessing the Performance of Ferrite Filters deploying Spread Spectrum modulation." In Proceedings of the Symposium F. WORLD SCIENTIFIC, 2003. http://dx.doi.org/10.1142/9789812704344_0039.

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Castilho, Vivian Moreira, José Humberto Andrade Sobral, Mangalathayil Ali Abdu, and Daniela Cristina Santana Arruda. "ASSOCIATION BETWEEN IONOSPHERIC PLASMA BUBBLES AND SPREAD-F." In 9th International Congress of the Brazilian Geophysical Society & EXPOGEF, Salvador, Bahia, Brazil, 11-14 September 2005. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2005. http://dx.doi.org/10.1190/sbgf2005-458.

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Bostan, Salih M., Julio V. Urbina, John D. Matthews, James K. Breakall, and Ross L. Dinsmore. "An unusual spread-F-like event over Arecibo." In 2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS). IEEE, 2021. http://dx.doi.org/10.23919/ursigass51995.2021.9560326.

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Castilho, H., Vivian Moreira, José Humberto Andrade; Abdu, Mangalathayil Ali; Arruda, and Daniela Cristina. "ASSOCIATION BETWEEN IONOSPHERIC PLASMA BUBBLES AND SPREAD-F." In 9th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2005. http://dx.doi.org/10.3997/2214-4609-pdb.160.sbgf458.

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Vryonides, P., H. Haralambous, and M. Fragoudi. "Spread F observations during low solar activity over Cyprus." In 2011 XXXth URSI General Assembly and Scientific Symposium. IEEE, 2011. http://dx.doi.org/10.1109/ursigass.2011.6050956.

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Pezzaniti, J. Larry, and Russell A. Chipman. "Point Spread Matrices: A Polarization Generalization of the Point Spread Function." In International Optical Design Conference. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/iodc.1994.dmtsg.72.

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This paper describes the point spread matrix, a matrix transfer function for relating an object polarization state to the polarization and intensity distribution across its image. Measurements of a point spread matrix of a 4-F optical system with large polarization aberration are presented. Measurements were performed with a Mueller matrix imaging polarimeter.
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S. Batista, Inez, M. A. Abdu, R. T. de Medeiros, and J. H. A. Sobral. "Equatorial Spread-F And Plasma Bubbles: A Step Towards Prediction." In 6th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 1999. http://dx.doi.org/10.3997/2214-4609-pdb.215.sbgf018.

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Abdu, M. A., J. R. Souza, I. S. Batista, J. H. A. Sobral, H. Takahashi, J. MacDougall, and E. R. de Paula. "Magnetospheric Disturbance Effects On Equatorial Spread F And Thermospheric Winds." In 7th International Congress of the Brazilian Geophysical Society. European Association of Geoscientists & Engineers, 2001. http://dx.doi.org/10.3997/2214-4609-pdb.217.425.

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Cueva, R. Y. C., C. Valladares, E. R. de Paula, and I. S. Batista. "Longitudinal variation of equatorial spread F occurrence over South America." In 12th International Congress of the Brazilian Geophysical Society & EXPOGEF, Rio de Janeiro, Brazil, 15-18 August 2011. Society of Exploration Geophysicists and Brazilian Geophysical Society, 2011. http://dx.doi.org/10.1190/sbgf2011-445.

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Reports on the topic "Spread F"

1

Kelley, Michael C. Prediction of Equatorial Spread F Based on Assimilation of Daytime GPS Data. Fort Belvoir, VA: Defense Technical Information Center, September 2006. http://dx.doi.org/10.21236/ada613105.

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Kelley, Michael C. Prediction of Equatorial Spread F Based on Assimilation of Daytime GPS Data. Fort Belvoir, VA: Defense Technical Information Center, September 2003. http://dx.doi.org/10.21236/ada628801.

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Kelly, Michael C. Prediction of Equatorial Spread F Based on Assimilation of Daytime GPS Data. Fort Belvoir, VA: Defense Technical Information Center, September 2007. http://dx.doi.org/10.21236/ada573169.

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Oppenheim, Meers, Yann Tambouret, and Yakov Dimant. First Kinetic Simulations of Equatorial Spread-F - Analysis of Kilometer-to-Meter Scale Irregularities. Fort Belvoir, VA: Defense Technical Information Center, February 2012. http://dx.doi.org/10.21236/ada567574.

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Eberle, Caitlyn, Oscar Higuera Roa, and Edward Sparkes. Technical Report: British Columbia heatwave. United Nations University - Institute for Environment and Human Security (UNU-EHS), August 2022. http://dx.doi.org/10.53324/gzuq8513.

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In summer 2021, air temperatures in Canada broke records multiple days in a row as a powerful heatwave spread over the Pacific Northwest, registering over 600 heat-related deaths and setting an all-time high-temperature record for the country at 49.6°C (121.3°F). An insufficient preparedness for such high temperatures meant that emergency response capacity was overwhelmed while the general public was unequipped to deal with anomalous temperatures. As climate change continues to make heat events such as this one more frequent and intense, the lessons learned during this disaster are critical to prepare for the next. This technical background report for the 2021/2022 edition of the Interconnected Disaster Risks report analyses the root causes, drivers, impacts and potential solutions for the British Columbia heatwave through a forensic analysis of academic literature, media articles and expert interviews.
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Shannon. L51584 Effect of Water Chemistry on Internal Corrosion Rates in Offshore Pipelines.pdf. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), March 1988. http://dx.doi.org/10.55274/r0010643.

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This work is an extension of a program reported in 1984 to establish factors which control corrosion of API line pipe in gas containing carbon dioxide and water. In this phase of the program, there were four objectives. One was to establish the temperature of maximum corrosion in the range of 75�, 100� and 175�F at 1000 psi in water saturated with carbon dioxide at partial pressures of 15 and 50 psia. The next was to explore the role of carbon content and microstructure in the steel, iron carbonate film formation, and resulting corrosion rates. The third was to examine the role of pre-existing mill scale and corrosion films on accelerating pitting attack. The final objective was to extend a spread sheet computer model to calculate corrosion rates from field data. Tests were run in a refreshed, recirculating autoclave at a total pressure of 1000 psi in water saturated with CO2 at partial pressures of 15 and 50 psia, and containing bicarbonate ion to adjust the pH either to 5 or 6. Six materials were tested: ASTM-A53B, two lots of API5LX-X52 and three lots of API5LX-X60. Samples were pulled at intervals for weight loss corrosion and to examine the surface films by electron microscope and metallography. After plotting the weight loss results, corrosion rates in mils per year (MPY) were calculated. The microstructure of the metal, the corrosion films of iron carbonate, and the weight loss results were then examined. The corrosion data were incorporated into a spread sheet computer model for users to calculate their own pipe line corrosion rates.
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Ullman, Diane E., Benjamin Raccah, John Sherwood, Meir Klein, Yehezkiel Antignus, and Abed Gera. Tomato Spotted Wilt Tosporvirus and its Thrips Vectors: Epidemiology, Insect/Virus Interactions and Control. United States Department of Agriculture, November 1999. http://dx.doi.org/10.32747/1999.7573062.bard.

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Objectives. The major aim of the proposed research was to study thrips-TSWV relationships and their role in the epidemiology of the virus with the aim of using this knowledge to reduce crop losses occurring due to epidemics. Our specific objectives were: To determine the major factors involved in virus outbreaks, including: a) identifying the thrips species involved in virus dissemination and their relative role in virus spread; b) determining the virus sources among wild and cultivated plants throughout the season and their role in virus spread, and, c) determining how temperature and molecular variations in isolates impact virus replication in plants and insects and impact the transmission cycle. Background to the topic. Tospoviruses are among the most important emerging plant viruses that impact production of agricultural and ornamental crops. Evolution of tospoviruses and their relationships with thrips vector species have been of great interest because of crop damage caused world wide and the complete absence of suitable methods of control. Tospoviruses threaten crops in Israel and the United States. By understanding the factors contributing to epidemics and the specific relationships between thrips species and particular tospoviruses we hope that new strategies for control can be developed that will benefit agriculture in both Israel and the United States. Major conclusions, solutions, achievements. We determined that at least three tospoviruses were involved in epidemics in Israel and the United States, tomato spotted wilt virus (TSWV), impatiens necrotic spot virus (INSV) and iris yellow spot virus (IYSV). We detected and characterized INSV for the first time in Israel and, through our efforts, IYSV was detected and characterized for the first time in both countries. We demonstrated that many thrips species were present in commercial production areas and trap color influenced thrips catch. Frankliniella occidentalis was the major vector species of INSV and TSWV and populations varied in transmission efficiency. Thrips tabaci is the sole known vector of IYSV and experiments in both countries indicated that F. occidentalis is not a vector of this new tospovirus. Alternate plant hosts were identified for each virus. A new monitoring system combining sticky cards and petunia indicator plants was developed to identify sources of infective thrips. This system has been highly successful in the U.S. and was used to demonstrate to growers that removal of plant sources of infective thrips has a dramatic impact on virus incidence. Finally, a putative thrips receptor mediating acquisition of TSWV was discovered. Implications, scientific and agricultural. Our findings have contributed to new control measures that will benefit agriculture. Identification of a putative thrips receptor for TSWV and our findings relative to thrips/tospovirus specificity have implications for development of innovative new control strategies.
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Ullman, Diane, James Moyer, Benjamin Raccah, Abed Gera, Meir Klein, and Jacob Cohen. Tospoviruses Infecting Bulb Crops: Evolution, Diversity, Vector Specificity and Control. United States Department of Agriculture, September 2002. http://dx.doi.org/10.32747/2002.7695847.bard.

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Objectives. The overall goal of the proposed research was to develop a mechanistic understanding of tospovirus evolution, diversity and vector specificity that could be applied to development of novel methods for limiting virus establishment and spread. Our specific objectives were: 1) To characterize newly intercepted tospoviruses in onion, Hippeastrum and other bulb crops and compare them with the known tomato spotted wilt virus (TSWV) and its isolates; 2) To characterize intra- and interspecific variation in the virus transmission by thrips of the new and distinct tospoviruses. and, 3) To determine the basis of vector specificity using biological, cellular and molecular approaches. Background. New tospoviruses infecting bulb crops were detected in Israel and the US in the mid-90s. Their plant host ranges and relationships with thrips vectors showed they differed from the type member of the Tospovirus genus, tomato spotted wilt virus (TSWV). Outbreaks of these new viruses caused serious crop losses in both countries, and in agricultural and ornamental crops elsewhere. In the realm of plant infecting viruses, the tospoviruses (genus: Tospovirus , family: Bunyaviridae ) are among the most aggressive emerging viruses. Tospoviruses are transmitted by several species of thrips in a persistent, propagative fashion and the relationships between the viruses and their thrips vectors are often specific. With the emergence of new tospoviruses, new thrips vector/tospovirus relationships have also arisen and vector specificities have changed. There is known specificity between thrips vector species and particular tospoviruses, although the cellular and molecular bases for this specificity have been elusive. Major conclusions, solutions and achievements. We demonstrated that a new tospovirus, iris yellow spot virus (IYSV) caused "straw bleaching" in onion (Allium cepa) and lisianthus necrosis in lisianthus (Eustoma russellianum). Characterization of virus isolates revealed genetic diversity among US, Brazilian, Dutch and Israeli isolates. IYSV was not seed transmitted, and in Israel, was not located in bulbs of infected plants. In the US, infected plants were generated from infected bulbs. The relationship between IYSV and Thrips tabaci was shown to be specific. Frankliniella occidentalis, the primary vector of many other tospoviruses, did not transmit IYSV isolates in Israel or the US. Furthermore, 1': tabaci populations varied in their transmission ability. Transmission was correlated to IYSV presence in thrips salivary glands. In Israel, surveys in onion fields revealed that the onion thrips, Thrips tabaci Lindeman was the predominant species and that its incidence was strongly related to that of IYSV infection. In contrast, in the U.S., T. tabaci and F. occidentalis were present in high numbers during the times sampled. In Israel, insecticides reduced onion thrips population and caused a significant yield increase. In the US, a genetic marker system that differentiates non-thrips transmissible isolates from thrips transmissible isolate demonstrated the importance of the M RNA to thrips transmission of tospoviruses. In addition, a symbiotic Erwinia was discovered in thrips and was shown to cause significant artifacts in certain types of virus binding experiments. Implications, scientific and agricultural. Rapid emergence of distinct tospoviruses and new vector relationships is profoundly important to global agriculture. We advanced the understanding of IYSV in bulb crops and its relationships with thrips vector species. The knowledge gained provided growers with new strategies for control and new tools for studying the importance of particular viral proteins in thrips specificity and transmission efficiency.
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Needham, Glenn R., Uri Gerson, Gloria DeGrandi-Hoffman, D. Samatero, J. Yoder, and William Bruce. Integrated Management of Tracheal Mite, Acarapis woodi, and of Varroa Mite, Varroa jacobsoni, Major Pests of Honey Bees. United States Department of Agriculture, March 2000. http://dx.doi.org/10.32747/2000.7573068.bard.

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Objectives: The Israeli work plan regarding HBTM included: (a) producing a better diagnostic method; (b) following infestations during the season and evaluating damage to resistant bees and, (c) controlling HBTM by conventional means under local conditions. For varroa our plans to try novel control (e.g. oil novel control (e.g. oil patties & essential oils) were initially delayed by very low pest populations, then disrupted by the emergence of fluvalinate resistance. We monitored the spread of resistance to understand it better, and analyzed an underlying biochemical resistance mechanism in varroa. The US work plan focused on novel management methods for both mites with an emphasis on reducing use of traditional insecticides due to resistance and contamination issues. Objectives were: (a) evaluating plant essential oils for varroa control; (b) exploring the vulnerability of varroa to desiccation for their management; and (c) looking for biological variation in HBTM that could explain virulence variability between colonies. Although the initial PI at the USDA Beltsville Bee Lab, W.A. Bruce, retired during the project we made significant strides especially on varroa water balance. Subcontracts were performed by Yoder (Illinois College) on varroa water balance and DeGrandi-Hoffman (USDA) who evaluated plant essential oils for their potential to control varroa. We devised an IPM strategy for mite control i the U.S. Background: Mites that parasitize honey bees are a global problem. They are threatening the survival of managed and feral bees, the well-being of commercial/hobby beekeeping, and due to pollination, the future of some agricultural commodities is threatened. Specific economic consequences of these mites are that: (a) apiculture/breeder business are failing; (b) fewer colonies exist; (c) demand and cost for hive leasing are growing; (d) incidences of bee pathogens are increasing; and, (e) there are ore problems with commercial-reared bees. As a reflection of the continued significance f bee mites, a mite book is now in press (Webster & delaplane, 2000); and the 2nd International Conference on Africanized Honey Bees and Bee Mites is scheduled (April, 2000, Arizona). The first such conference was at OSU (1987, GRN was co-organizer). The major challenge is controlling two very different mites within a colony while not adversely impacting the hive. Colony management practices vary, as do the laws dictating acaricide use. Our basic postulates were that: (a) both mites are of economic importance with moderate to high infestations but not at low rates and, (b) once established they will not be eradicated. A novel strategy was devised that deals with the pests concomitantly by maintaining populations at low levels, without unnecessary recourse to synthetic acaricides. Major Conclusions, Solutions, Achievements: A major recent revelation is that there are several species of "Varroa jacobsoni" (Anderson & Trueman 1999). Work on control, resistance, population dynamics, and virulence awaits knowing whether this is a problem. In the U.S. there was no difference between varroa from three locales in terms of water balance parameters (AZ, MN & PA), which bodes well for our work to date. Winter varroa (U.S.) were more prone to desiccation than during other seasons. Varroa sensitivity to desiccation has important implications for improving IPM. Several botanicals showed some promise for varroa control (thymol & origanum). Unfortunately there is varroa resistance to Apistan in Israel but a resistance mechanism was detected for the first time. The Israel team also has a new method for HBTM diagnosis. Annual tracheal mite population trends in Israel were characterized, which will help in targeting treatment. Effects of HBTM on honey yields were shown. HBTM control by Amitraz was demonstrated for at least 6 months. Showing partial resistance by Buckfast bees to HBTM will be an important IPM tactic in Israel and U.S.
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Fridman, Eyal, and Eran Pichersky. Tomato Natural Insecticides: Elucidation of the Complex Pathway of Methylketone Biosynthesis. United States Department of Agriculture, December 2009. http://dx.doi.org/10.32747/2009.7696543.bard.

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Plant species synthesize a multitude of specialized compounds 10 help ward off pests. and these in turn may well serve as an alternative to synthetic pesticides to reduce environmental damage and health risks to humans. The general goal of this research was to perform a genetic and biochemical dissection of the natural-insecticides methylketone pathway that is specific to the glandular trichomes of the wild species of tomato, Solanumhabrochaites f. glabratum (accession PI126449). Previous study conducted by us have demonstrated that these compounds are synthesized de novo as a derivate pathway of the fatty acid biosynthesis, and that a key enzyme. designated MethylketoneSynthase 1 (MKS 1). catalyzes conversion of the intermediate B-ketoacyl- ACPs to the corresponding Cn-1 methylketones. The approach taken in this proposed project was to use an interspecific F2 population. derived from the cross between the cultivated lV182 and the wild species PIl26449. for three objectives: (i) Analyze the association between allelic status of candidate genes from the fatty acid biosynthesis pathway with the methylketone content in the leaves (ii) Perform bulk segregant analysis of genetic markers along the tomato genome for identifying genomic regions that harbor QTLs for 2TD content (iii) Apply differential gene expression analysis using the isolated glands of bulk segregant for identifying new genes that are involved in the pathway. The genetic mapping in the interspecific F2 population included app. 60 genetic markers, including the candidate genes from the FAS pathway and SSR markers spread evenly across the genome. This initial; screening identified 5 loci associated with MK content including the candidate genes MKS1, ACC and MaCoA:ACP trans. Interesting observation in this genetic analysis was the connection between shape and content of the glands, i.e. the globularity of the four cells, typical to the wild species. was associated with increased MK in the segregating population. In the next step of the research transcriptomic analysis of trichomes from high- and 10w-MK plants was conducted. This analysis identified a new gene, Methy1ketone synthase 2 (MKS2), whose protein product share sequence similarity to the thioesterase super family of hot-dog enzymes. Genetic analysis in the segregating population confirmed its association with MK content, as well as its overexpression in E. coli that led to formation of MK in the media. There are several conclusions drawn from this research project: (i) the genetic control of MK accumulation in the trichomes is composed of biochemical components in the FAS pathway and its vicinity (MKS 1 and MKS2). as well as genetic factors that mediate the morphology of these specialized cells. (ii) the biochemical pathway is now realized different from what was hypothesized before with MKS2 working upstream to I\1KS 1 and serves as the interface between primary (fatty acids) and secondary (MK) metabolism. We are currently testing the possible physical interactions between these two proteins in vitro after the genetic analysis showed clear epistatic interactions. (iii) the regulation of the pathway that lead to specialized metabolism in the wild species is largely mediated by transcription and one of the achievements of this project is that we were able to isolate and verify the specificity of the MKS1 promoter to the trichomes which allows manipulation of the pathways in these cells (currently in progress). The scientific implications of this research project is the advancement in our knowledge of hitherto unknown biochemical pathway in plants and new leads for studying a new family in plants (hot dog thioesterase). The agricultural and biotechnological implication are : (i) generation of new genetic markers that could assist in importing this pathway to cultivated tomato hence enhancing its natural resistance to insecticides, (ii) the discovery of MKS2 adds a new gene for genetic engineering of plants for making new fatty acid derived compounds. This could be assisted with the use of the isolated and verified MKS1 promoter. The results of this research were summarized to a manuscript that was published in Plant Physiology (cover paper). to a chapter in a proceeding book. and one patent was submitted in the US.
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