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Palinologia de espécies da tribo Eupatorieae (Compositae Giseke) ocorrentes na Restinga de Carapebus, Carapebus, Rio de Janeiro
Brazilian Journal of Botany , 2000,
Abstract: Foram estudados os gr os de pólen de sete táxons pertencentes à tribo Eupatorieae, ocorrentes na Restinga de Carapebus, Carapebus, Estado do Rio de Janeiro. S o eles: Barrosoa atlantica King & Robins., B. betonicaeformis (DC.) King & Robins., Mikania belemii King & Robins., M. cordifolia Willd., M. glomerata Spreng., M. micrantha H.B.K., M. trinervis Hook & Arn. e Trichogoniopsis podocarpa (DC.) King & Robins. A tribo apresentou em comum, gr os de pólen pequenos a médios, oblato-esferoidais a prolato-esferoidais, tricolporados, sexina espinhosa e cavada. Os táxons puderam ser separados quando foram consideradas a forma polínica, as dimens es do espinho e a distancia entre eles. Assim, foi possível formar dois conjuntos de espécies identificados pela forma polínica: o primeiro, com forma oblato-esferoidal, composto por Barrosoa atlantica, Mikania micrantha e M. trinervis e o segundo, com forma prolato-esferoidal, composto por Barrosoa betonicaeformis, Mikania belemii, M. cordifolia, M. glomerata e Trichogoniopsis podocarpa. Os resultados obtidos, em compara o à literatura corrente, permitem concluir que a tribo Eupatorieae é, palinologicamente, homogênea, porém algumas espécies podem ser separadas pelo gr o de pólen, exceto M. glomerata de T. podocarpa e M. belemii de M. cordifolia.
Compositae dermatitis
Jovanovi? Mirjana,Polja?ki Mirjana N.
Medicinski Pregled , 2003, DOI: 10.2298/mpns0302043j
Abstract: Introduction Compositae dermatitis is an allergic contact dermatitis caused by plant species of the Compositae family. The first report of a cutaneous reaction to the Chrysanthemum genus was made by Howe JS in 1887. In 1895 Maiden JH reported about skin lesions among men working with Tagetes minute Case reports of contact allergic-ragweed dermatitis appeared in the American literature as early as 1919. The North American feverfew - Parthenium Hysterophorus was brought to India from America in 1956 and it caused thousands of cases of so-called parthenium dermatitis. Ragweed and parthenium dermatitis became prototypes for the classic, so-called 'airborne' Compositae dermatitis, that affects primarily exposed skin surfaces, and produces a universal erythroderma. Epidemiology The frequency of contact allergy to Compositae in Europe is higher than previously believed. It occurs most frequently in middle-aged and elderly persons, but also in all age groups During the two past decades a more equal sex ratio has been established. The prevalence varies from 0.7-1.4% in the general population, up to 4.5% among occupationally exposed persons. Compositae allergy is among the top ten contact sensitivities in Europe. In North Europe plants were the cause of 4.4% cases of occupational allergic contact dermatitis. Etiology and pathogenesis Among cultivated Compositae plants, Chrysanthemum is considered to be a major sensitizer in Europe (60%). Among the edible types, it is lettuce - Lactuca sativa and endive Cichorium endivia (20-30%), and wild-growing feverfew - Tanacetum parthenium (70-90%), tansy - Tanacetum vulgare (54%), and dandelion - Taraxacum officinale (65%). Sesquiterpene lactones are the main sensitizers of the Compositae family. Other components thiophenes and acetylenes are said to elicit only phytophotodermatitis, but recent studies have demonstrated that some thiophenes and benzofuran derivates possess not only phototoxic activity, but also sensitizing properties. Photosensitivity is present in 22-75% Compositae sensitive individuals. Extracts from Compositae are known to be phototoxic in vitro Photoreactivity of alpha-methylene-gamma-lactone group of sesquiterpene-lactone directed towards the DNA base thymine, thus producing intermolecular 2+2 photoadducts (antigen within the cell), was also thought to be related to photosensitivity. Clinical manifestations vary from generalized eczema (20-30%), eczema of hands and face (24%), hand (36-44%) or facial eczema (11-28%). 65% of patients have vesicular hand eczema Diagnosis Routine patch testing with sesqui
Anatomia foliar de Richterago Kuntze (Mutisieae, Asteraceae)
Melo-de-Pinna, Gladys Flávia de A.;
Acta Botanica Brasilica , 2004, DOI: 10.1590/S0102-33062004000300017
Abstract: leaf anatomy of richterago species revealed rather variability concerning mesophyll organization and stomata arrangement. as a character of taxonomic value, only non-glandular thricomes were used to compare r. arenaria and r. lanata,r. conduplicata and r. radiata, whose leaves are morphologically similar. anatomical xeromorphic characters, e.g. the bundles sheath extensions and terminal tracheids were observed in all species. the waterside species (r. polymorpha e r. riparia) showed hydathodes in the leaves, which represent the first record in mutisieae.
Dos especies nuevas de Acourtia (Compositae, Mutisieae) del estado de Querétaro (México).  [cached]
Jerzy Rzedowski,Graciela Calderón de Rzedowski
Acta botánica mexicana , 1990,
Presence of flavonoids and intrafamilial ciassification of the Compositae
Bogus?aw Wi?komirski,Andrzej Batko
Acta Societatis Botanicorum Poloniae , 1993, DOI: 10.5586/asbp.1993.009
Abstract: The structure of flavonoids isolated from plants of the Compositae family was applied for comparision of two classifications (Wagenitz 1976 and Takhtadjan 1987). The methods of numerical taxonomy, both phenetic and phylogenetic, confirm that Takhtadjan's classication based on morphological and anatomical data is more adequate to the flavonoid diversity.
Contact dermatitis from compositae plants  [cached]
Sharma S,Kaur S
Indian Journal of Dermatology, Venereology and Leprology , 1990,
Abstract: Eighty patients (58 males and 22 females) suspected of compositae contact dermatitis and 22 controls were investigated using ethanolic plants extracts., Fifty four (68%) patients and none of the controls had positive patch tests. Forty five (56%) of these patients showed positive reactions with, extracts of only a single Compositae plant. Parthenium hysterophorus produced positive reactions in 51%, Chrysanthemum morifolium in 23%, Dahlia pinnata in 9% and Tagetes indica in 4% patients. The highest number (84%) of patients with positive patch tests were exposed to these plants during their occupation.
Control Parameters of the Tribo Complex Systems in Dynamic Testes Specifications
Nasir Al-Kloub
Journal of Applied Sciences , 2004,
Abstract: The present study deals with the control methods of the reliability parameters regulated by the states branch standards managing documents and standards of the enterprises. Its reliability and quality determine the optimum choice of Tribo system elements. It is inconceivable without the information about the processes of friction and wear proceeding in system at each stage. Therefore, creation of Tribo system with test bench parameters begins with search for the information, which is the authentic source, are the tests.
Contact allergy to Compositae plants in patients with atopic dermatitis  [PDF]
Jovanovi? Marina,Polja?ki Mirjana N.,?uran Verica D.,Vujanovi? Ljuba M.
Medicinski Pregled , 2004, DOI: 10.2298/mpns0406209j
Abstract: To investigate the frequency of Compositae sensitivity is one of the most important goals of current dermatology and allergology. We have patch tested 30 adult patients suffering from “extrinsic” atopic dermatitis with sesquiterpene lactone mix and Compositae mix including Compositae mix individual ingredients, extracts of arnica (Arnica montana), chamomile (Chamomilla recutita), tansy (Tanacetum vulgare), feverfew (Tanacetum parthenium) and yarrow (Achillea millefolium) as well as with specific series for patients with atopic dermatitis. All allergens were purchased from Hermal-Trolab (Reinbek, Germany). There were 6 (20%) patients positive to Compositae mix only, and 3 (10%) patients positive to both Compositae mix and sesquiterpene lactone mix. Among 9 Compositae mix-sensitive patients 8 (88.8%) were positive to at least 1 of its individual ingredients: 5 (55.5%) to chamomile, 4 (44.4%) to arnica, 2 (22.2%) to tansy, and 2 (22.2%) to feverfew. Among Compositae-sensitive patients 78.8% had other contact allergies, most often to nickel (33.3%). Since our study represents the first report on contact allergy to Compositae among patients with "extrinsic" type of atopic dermatitis, it substantiates the statement that atopy represents a risk factor for Compositae allergy. In conclusion, the overall prevalence of 30% Compositae-sensitive among patients with “extrinsic” atopic dermatitis detected in our study represents a basal sesquiterpene lactone mix detection rate of 10%, reinforced and safely supplemented by 20% by testing with the Compositae mix.
Research Progress in Tribo-Electrochemistry and Tribo-Electrochemical Polishing

ZHAI Wen-jie,

摩擦学学报 , 2006,
Abstract: A review is given on the current state and recent progress in the research of tribo-electrochemistry in aqueous media and non-aqueous media, respectively, with special attention being paid to the triboelectrochemical mechanisms for the control of friction and wear. Along with a summary on the conventional polishing principles of hard and brittle materials, the tribo-electrochemical polishing method is proposed. Preliminary test results show that tribo-electrochemical polishing is promising to become the critical technology in the high efficient polishing and planarization of microelectronic materials.
The Compositae of Xizang (Tibet)

Shih Chu,Chen Yi-Ling,

中国科学院研究生院学报 , 1982,
Abstract: 1) The Compositae in Tibet so far known comprise 508 species and 88 genera, which nearly amounts to one fourth of the total number of genera and one third of the total number of species of Compositae in all China, if the number of 2290 species and 220 genera have respectively been counted in all China. In Tibet there are all tribes of Com- positae known in China, and surprisingly, the large tribes in Tibetan Compositae are also large ones in all China and the small tribes in Tibet are also small ones in all China. Generally speaking, the large genera in Tibet are also large ones in all China and the small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China. In the Compositae flora of Tibet, there are only 5 large genera each containing 30 species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And 5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium, Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87% of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc. 2) The constituents of Compositae flora in Tibet is very closely related to those of Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation is evidently brought about by the geographycal proximity in which the Hengtuang Shan Range links southeastern and eastern Tibet with northern and northwestern Sichuan- Ynnnan. With India the Tibetan Compositae have 59 genera and 132 species in common, also showing close floristic relationships between the two regions. Apparently the floris- tic exchange of Compositae between Tibet and India is realized by way of the mountain range of the Himalayas. The mountain range of the Himalayas, including the parallel ranges, plays a important role as a bridge hereby some members of the Compositae of western or northern Central Asia and of the northern Africa or of western Asia have migrated eastwards or southeastwards as far as the southern part of Fibet and northern part of India, or hereby some Compositae plants of eastern and southeastern Asia or Asia Media have migrated northwestwards as the northern part of Central Asia. Some of the species and genera in common to both Tibet and Sinjiang indicate that this weak floristical relationship between these regions is principally realized through two migration routes: one migration route is by way of the Himalayas including the parallel ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu, Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa. However, Tibet is not entirely situated at a migration crossroad of the floral ele- ments. An ample amount of the dat
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