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1.
A total of 25 aphid species were collected from 49 ornamental plant species in S?o Carlos-S?o Paulo, Brazil; 12 aphids were monophagous, four oligophagous and nine polyphagous. A total of 58 aphid-plant associations are recorded, 43 unknown from Brazil. Eucarazzia elegans (Ferrari, 1872) (Aphididae: Aphidinae: Macrosiphini) is recorded for the first time from Brazil, and Nectandra megapotamica Spreng. (Lauraceae) is recorded for the first time as host plant for Lizerius tuberculatus (E.E. Blanchard, 1939) (Drepanosiphidae: Drepanosiphinae: Lizeriini). We also describe the injuries caused by aphids to the ornamental plants.  相似文献   

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All morphs of two species of the genus Dysaphis, D. radicola (Mordv.) and D. rumecicola (Hori), living on plants of the family Polygonaceae, are described in detail. Morphometrical analysis has shown that D. radicola meridialis Shaposhnikov, 1964 is merely a synonym of D. radicola radicola (Mordvilko, 1897), and D. albocinerea (Hille Ris Lambers, 1956) and D. rheicola Daniyarova ex Narzikulov et Daniyarova, 1971, synonyms of D. rumecicola (Hori, 1935). D. emicis (Mimeur, 1935) is downgraded to a subspecies of D. rumecicola. Keys to species of the genus Dysaphis living on plants of the family Polygonaceae are provided.  相似文献   

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Peanut is an economically important legume nodulated by slow-growing bacteria of the genus Bradyrhizobium. In this study, a collection of native slow-growing peanut rhizobial isolates from Argentina was obtained and characterized. The phenotypical characterization included the determination of the symbiotic properties, whereas the genetic and phylogenetic diversity was assessed through ERIC-PCR and sequencing of the internal transcribed spacer (ITS) region, as well as the dnaK and nodA genes. The results obtained indicated that peanut nodulating bradyrhizobia were phenotypically and genotypically diverse, and included locally adapted variants of B. yuanmingense and B. iriomotense carrying novel nodA alleles.  相似文献   

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A survey of aphids was carried out during the period 2008-2011 in different regions of Algeria by collecting and identifying aphids and their host plants. Aphids were collected from 46 host plants. Forty-six species were reported including thirty-six species which were recorded for the first time in this country and thirty species which were recorded for the first time in the Maghreb (North Africa). This study extends the number of known Algerian aphid to 156 species.  相似文献   

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《Endocrine practice》2011,17(3):412-417
ObjectiveTo determine whether environmental perchlorate exposure adversely affects thyroid function in women in the first trimester of pregnancy.MethodsFirst-trimester pregnant women were recruited from prenatal clinics in the Los Angeles County Hospital, Los Angeles, California, and in the Hospital Universitario de Maternidad dependent Universidad Nacional de Córdoba, Córdoba, Argentina, between 2004 and 2007. Spot urine and blood specimens were obtained during the clinic visit. Urinary perchlorate, iodine, and creatinine were measured, and thyroid function tests were performed.ResultsThe study included 134 pregnant women from Los Angeles, California (mean gestational age ± SD = 9.1 ± 2.2 weeks), and 107 pregnant women from Córdoba, Argentina (mean gestational age = 10.0 ± 2.0 weeks). Median urinary iodine values were 144 mg/L in California and 130 mg/L in Argentina. Urinary perchlorate levels were detectable in all women (California: median, 7.8 mg/L [range, 0.4-284 mg/L] and Argentina: median, 13.5 mg/L [range, 1.1-676 mg/L]). Serum thyroperoxidase antibodies were detectable in 21 women from California (16%) and in 17 women from Argentina (16%). Using Spearman rank correlation analyses, there was no association between urinary perchlorate concentrations and serum thyrotropin, free thyroxine index, or total triiodothyronine values, including within the subset of women with urinary iodine values less than 100 mg/L. In multivariate analyses using the combined Argentina and California data sets and adjusting for urinary iodine concentrations, urinary creatinine, gestational age, and thyroperoxidase antibody status, urinary perchlorate was not a significant predictor of thyroid function.ConclusionsLow-level perchlorate exposure is ubiquitous, but is not associated with altered thyroid function among women in the first trimester of pregnancy. (Endocr Pract. 2011;17:412-417)  相似文献   

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Hoplias malabaricus behaves as a zoophagous and euryphagic species with a strong tendency to eat fish during its entire life. Fish begin to constitute its main food at approximately 200 mm standard length. Insects are important for fish smaller than 50 mm. Crustaceans are of lesser importance for both size groups."Mojarras" (genus Astyanax), the characin Odontostilbe microcephala, and the catfish Pimelodus albicans are its main prey. The relative importance of each prey type varies with predator length.In high summer more food is eaten by H. malabaricus, and digestion rate, related to the higher temperatures, is also higher. During colder seasons feeding activities decreases markedly.  相似文献   

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In Argentina, most information on hepatitis C virus (HCV) genotype distribution comes from studies carried out in Buenos Aires (east province). In order to identify HCV subtypes in central Argentina, nucleotide sequencing of core region was performed in samples from 36 patients living in Córdoba, the second most populated province of Argentina. The sequence analysis identified subtype 2c as the most prevalent (50%), followed by subtype 1b (33%) and to a lesser extent by subtypes 1a (11%), 3a (3%) and 4a (3%). This is the first report of circulation of HCV subtype 2c in this region of Argentina and also such high prevalence has never been found before in the genotype distribution of South America.  相似文献   

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Surnames analysis is useful for populations in which only written documents remain, as is the case for historical populations. In Córdoba province, Argentina, census records contain nominal data of inhabitants, including information on sex, age, ethnosocial category, civil status, occupation, place of birth, and residence, that can be analyzed using surnames. Relationship indicators within and among ecclesiastic units in Córdoba were estimated by isonymy for the adult white population registered in the 1813 census. The Rii, Rij, and R(ST) coefficients and the surname abundance indicator (a) were calculated. Lasker's distances among categories of population units were used to cluster the 16 provincial population categories. Gradients for kinship within population and for surname diversity were in agreement with the principal areas and waves of original settlement in the province. The main population clusters reflect those areas, whereas minor clusters coincide with the network of roads existing in the territory by 1813. The structure of the white population in Córdoba province was determined by the geographic location of the original waves of settlement, and it followed a pattern of relationships conditioned by the routes connecting population units in the Colonial period.  相似文献   

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Temperature and humidity conditions affect livestock production in Central Argentina. This study evaluates the risk of thermal stress affecting dairy production. The temperature-humidity index (THI) was used to analyze the regional and seasonal effects of temperature and humidity. Statistically, the THI was found to be normally distributed. The probability of occurrence of a daily THI higher than 72 was 40% for Río Cuarto during January. Regional variability of THI indicates a low risk of harmful extreme thermal stress conditions. The probability of THI being 78 or above ranges between 4% and 10% for the main dairy region of Córdoba during January. Also, in January and February, dairy production losses between 3 and 4 l cow(-1) day(-1) could be expected with a frequency of 5% in Río Cuarto and 15% in Villa de María de Río Seco.  相似文献   

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We report the aerobic biodegradation of Microcystin-RR (MC-RR) by a bacterial strain isolated from San Roque reservoir (Córdoba – Argentina). This bacterium was identified as Sphingomonas sp. (CBA4) on the basis of 16S rDNA sequencing. The isolated strain was capable of degrading completely MC-RR (200 μg l−1) within 36 h. We have found evidence that MC-RR biodegradation pathway by this Sphingomonas sp. strain would start by demethylating MC-RR, affording an intermediate product, which is finally biodegraded by this strain within 72 h. Our results confirm that certain environmental bacteria, living in the same habitat as toxic cyanobacteria, have the capability to perform complete biodegradation of MC, leading to natural bioremediation of waterbodies. The bacterium reported here presents genetic homologies with other strains that degrade MC-LR. However, initial demethylation of MC-RR has been not described previously, raising questions on the probable presence of different biodegradation pathways for different MC variants.  相似文献   

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We report the presence of the competent vector for Leishmaniaspp, Migonemyia migonei, and theEvandromyia cortelezzii-sallesi complex south of its known distribution in the central temperate region of Argentina, in the province of Córdoba. The persistence of this phlebotomine in the northern border of the province, its association with a case of cutaneous leishmaniasis, and the new record in the outskirts of the city of Córdoba, the second most populated in the country, strengthens the need for regular vector surveillance and a case detection-sensitive health system in vulnerable regions, even in temperate climates.  相似文献   

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Cohen  Rosa Graciela 《Hydrobiologia》2002,486(1):91-100
At present, the American genus Thamnocephalus has three species, recorded from several states of U.S.A., México and Venezuela: Thamnocephalus platyurus Packard, T. mexicanus Linder and T. venezuelensis Belk & Pereira. The new species Thamnocephalus salinarum, from a turbid saline temporary pond inside the Salinas Grandes of Córdoba, Argentina is described here. The new species differs from all other congeners by the presence in the male, of an unbranched frontal appendage and a pair of soft cordiform parapenial lobes; also, by the sexually dimorphic caudal fin-like lobe. This new species may represent a new genus, however since only five specimens were collected it was not possible to observe if the penial ornamentation conforms to the Thamnocephalus type. Therefore, a conservative position is taken until new material allows proper analysis, by keeping the new species in the genus Thamnocephalus under the new subgenus Simplicephalus.  相似文献   

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Species do not respond identically to the presence of humans, and this may have consequences at higher-levels of ecological organization. We established bird transects on and off recreational trails in the high Córdoba Mountains of Argentina, a biogeographic island characterized by high levels of endemism, to examine the effect of human visitation at three different levels: (a) community (avian species richness and diversity), (b) guild (relative density of carnivores, granivores, insectivores, and omnivores), and (c) population (relative density of individual bird species). Human presence in the high Córdoba Mountains decreased avian species richness and diversity, and reduced insectivorous relative density, but we did not detect significant effects on granivores, omnivores, and carnivores. At the population level, 6 of 28 species were negatively affected by human visitation; four of these species are of conservation concern. Our results show negative responses to recreationists at multiple levels (e.g., reductions in density, displacement of species from highly visited areas), which may be related to spatial and temporal access to suitable resources, physical disturbance or species-specific tolerance thresholds. Our study area had lower levels of human visitation relative to other protected areas in the Northern Hemisphere, which raises the issue of whether this kind of biogeographically isolated habitat may be too fragile to sustain increasing levels of tourism.  相似文献   

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The Hepatitis C Virus Genotype 2 subtype 2c (HCV-2c) is detected as a low prevalence subtype in many countries, except in Southern Europe and Western Africa. The current epidemiology of HCV in Argentina, a low-prevalence country, shows the expected low prevalence for this subtype. However, this subtype is the most prevalent in the central province of Córdoba. Cruz del Eje (CdE), a small rural city of this province, shows a prevalence for HCV infections of 5%, being 90% of the samples classified as HCV-2c. In other locations of Córdoba Province (OLC) with lower prevalence for HCV, HCV-2c was recorded in about 50% of the samples. The phylogenetic analysis of samples from Córdoba Province consistently conformed a monophyletic group with HCV-2c sequences from all the countries where HCV-2c has been sequenced. The phylogeographic analysis showed an overall association between geographical traits and phylogeny, being these associations significant (α = 0.05) for Italy, France, Argentina (places other than Córdoba), Martinique, CdE and OLC. The coalescence analysis for samples from CdE, OLC and France yielded a Time for the Most Common Recent Ancestor of about 140 years, whereas its demographic reconstruction showed a “lag” phase in the viral population until 1880 and then an exponential growth until 1940. These results were also obtained when each geographical area was analyzed separately, suggesting that HCV-2c came into Córdoba province during the migration process, mainly from Europe, which is compatible with the history of Argentina of the early 20th century. This also suggests that the spread of HCV-2c occurred in Europe and South America almost simultaneously, possibly as a result of the advances in medicine technology of the first half of the 20th century.  相似文献   

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Feedstuffs used for poultry nutrition in Argentina were analyzed for fungal flora and natural incidence of mycotoxins. Survey of 120 samples of poultry feeds, taken from May 1998 to April 1999, showed the presence of 15 genera of filamentous fungi. The predominant genera wereFusarium spp. andPenicillium ssp., isolated in 67.5 % of the samples, followed byAspergillus spp. (57.5 %). Yeast, were significantly isolated from most of the samples. Species identification was carried down for the toxigenic genera. Fungal total counts of poultry feeds ranged from 2.0 × 103 to 3.0 × 105 CFU g-1 The fungal total counts during two months of sampling, were slightly over the limit value of 1 × 105 CFU g-1, which ensure the hygienic quality of the feed. Potentially toxicogenic species presented moderate mean colony counts. Many of the fungi isolated from poultry feeds are mycotoxin producers. Fumonisins had the highest incidence, and were found in 97 % of the analyzed samples followed by aflatoxin B1 (46 %), zearalenone (18 %) and deoxynivalenol (6 %). On the co-occurrence of both carcinogenic mycotoxins, all of the FBs contaminated feed samples were co-contaminated with AFB1. The results show the relevance of the samples screening for viable fungi propagules and the surveillance of their associated mycotoxins in poultry feeds.  相似文献   

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