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1.
The aquatic insects have been used to evaluate water quality of aquatic environments. The population of aquatic insects and the water quality of the area were characterized according to the natural and human alterations present in the study site. During the monthly-survey, pH, DO, temperature, water level, DBO, PO4 and NO3 were measured. Biological indexes (abundance, species richness and the BMWP-CR) were used to evaluate the water quality. No relation between environmental and aquatic insects was detected. Temporal and spatial differences attributed to the flow events (temporal) and the presence of Pe?as Blancas reservoir (spatial). In the future, the investigations in Pe?as Blancas watershed need to be focused on determining the real influence of the flows, sediment release and the possible water quality degradation because of agriculture activities.  相似文献   

2.
正Translational medicine refers to the conversion of scientific discoveries into improvements in medical practice.‘From bench to bedside and back’is a phrase that is often used to describe the two-way information flow in translational medicine.On one hand,scientists working at the bench make new discoveries that enable clinicians to revolutionize  相似文献   

3.
The Jahrum Formation act as reservoir rocks in the Zagros Mountains west of Iran. For the study of this formation, a stratigraphic section of Lapoee which is situated north of Shiraz has been examined. Petrographic and stratigraphic results along with field observations show that the Jahrum Formation consists of cream-grey thin-to-medium-bedded limestone so that at the top of the formation, they are locally changed to dolomite. The Jahrum Formation overlies the Sachun Formation. We also found Nubecularids as paleoecology indicators in middle parts of the Jahrum Formation. The presence of Nubecularids in the Lapoee stratigraphic section (i.e. the Jahrum Formation) indicates a lagoon depositional environment.  相似文献   

4.
The viable propagule banks of a temporary stream were studied from sections with different agricultural history. Hatching of zooplankton (copepods, rotifers and cladocerans) was recorded in the laboratory under controlled temperature and light conditions from an agriculturally modified area with average hydroperiods of about a week per year and two semi-natural reference areas with average hydroperiods of more than 3 weeks per year. We found significant differences in both taxon richness and abundance of zooplankton hatching between areas, which were lower in the agriculturally modified section, compared to the reference sections. Another factor likely to have influenced hatching in our experiment was conductivity, which differed between the two reference sections and might have affected hatching at high conductivities. For restoration purposes, hydrological reconnection of stream segments is important to facilitate dispersal from the high diversity upstream segments to the depleted sites downstream.  相似文献   

5.
《Plains anthropologist》2013,58(15):2-23
Abstract

A re-study based upon translations of the original documents is made of the many published routes suggested for Coronado’s and Oñate’s routes into the Plains. The point is made that disagreements among historians stem from the differing initial point of reference, a bridge thrown across a large river. Others have identified this river as the Pecos but Schroeder feels the evidence shows this is the Canadian River. Coronado’s route is then traced across the Plains to the Cimarron River. From this point to Quivira Schroeder is in agreement with other historians that the route was along the Arkansas River. He also agrees with Wedel’s archaeological location of Quivira as being in the Rice-McPherson County area of Kansas. The separate routes of Coronado’s army and party are then traced back to the Pecos Pueblo along what Schroeder deduces to have been more or less a straight line across the Oklahoma-Texas Panhandles.

Oñte’s later trip into the Plains is compared with Coronado’s. Considered in some detail are the intervening location of the Apachean and Plains Caddoan groups in relation to each other as suggested by the statements of the various chroniclers. The conclusion is reached that Oñate’s Quivira was located farther south than that visited by Coronado. Schroeder feels that Wedel’s archaeological work supports this view and concludes that Oñate’s Quivira extended slightly farther south along the Chicaskia River near Ponca City, Oklahoma.  相似文献   

6.
The patterns of serum luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone and estradiol-17β during the estrous cycle of six crossbred (Alpine × Nubian × Native) and six native goats showing a 21 day estrous cycle in a semiarid zone of Venezuela are presented. In the crossbred goats, FSH had two significant peaks on Days 19 and 0 (33 ± 8.6 ng ml−1 and 25 ± 6 ng ml−1, respectively); in contrast, native goats only had one significant peak on the day of estrus (22 ± 2 ng ml−1), with the increase beginning on Day 17. During the follicular phase of crossbred goats, estradiol-17β and LH increased to 28 ± 6 pg ml−1 and 23 ± 6.9 ng ml−1, respectively, on Day 0. Prior to Day 0, LH increased to 10.0 ± 4.9 ng ml−1 on Day 18, decreasing to 1.5 ng ml−1 on Day 19, while estradiol-17β was increasing. This relationship between estradiol-17β and LH was not found to exist in native does, which presented a LH peak on Day 0 (30 ± 8 ng ml−1 and 35 ± 10 ng ml−1 in first and second estrus, respectively). LH basal levels were notably higher in native does. The highest concentrations of progesterone (10 and 12 ng ml−1) were detected on Days 12 and 15 in crossbred and native females, respectively. In conclusion, the relationship between estradiol-17β and gonadotropins during the follicular phase in crossbred goats suggests negative and positive feedback effects on both LH and FSH. Serum concentrations of LH were higher in native than in crossbred goats, whereas concentrations of FSH were higher in crossbred does. Thus, genetic factors need to be taken into account when comparing blood levels of gonadotropins in goats raised in tropical semiarid zones.  相似文献   

7.
Flowering and fruiting phenological patterns at the individual-, population-, and community level were studied in a southern Spanish scrub community composed of 30 shrub species. Few individuals of any species produced a high number of flowers. Intrapopulation deviation in the peak time of flowering showed a strong and positive skewness. Relative flowering duration, however, displayed a virtually normal distribution. Generally, species flowering in spring have a short flowering time, while species flowering earlier or later in the year show significantly longer flowering periods. Species were in bloom throughout the year, but there was a major peak during spring and two lesser ones in autumn and early summer. Shallow rooting taxa in typically mediterranean genera displayed a strategy of spring flowering and summer fruiting. Summer and autumn flowering occurred among heath-like shrubs of relatively wet places, and forest-associated, vertebrate-dispersed species which commonly have underground storage organs. Species with ripe fruits presented two peaks, the major one during the summer including the majority of taxa with seeds dispersed by non-vertebrate agents. There was a minor fruiting peak in autumn dominated by taxa that rely on vertebrates for dispersal. The complex seasonal patterns observed are interpreted in relation to environmental conditions and physiological constraints on species living in a highly seasonal climate.  相似文献   

8.
A list of 244 bryophytes (67 hepatics and 177 mosses) from Sierra de Peña Sagra (Cantabria) is given; Ctenidium molluscum var. sylvaticum is new record from the Iberian Peninsula and 27 taxa are new records for this province. We remark the presence of Cephaloziella hampeana, Lejeunea lamacerina, Kurzia pauciflora, Sphagnum brevifolium, S. girgensohnii, Hypnum hamulosum, Orthotrichum consimile, Ulota bruchii, Mnium lycopodioides, Plagiomnium medium subsp. medium, Grimmia anomala and Tortella densa.  相似文献   

9.
The phenology of tree species in environments that are subject to strong climatic seasonality is mainly determined by water availability, which may vary as a function of wood density. The relationship among phenology, water potential, wood density and the capacity of water storage in the stem were determined for woody species of caatinga vegetation (dry forest) in the semiarid region of NE Brazil. Leaf flush and fall, flowering and fruiting events were recorded over a 31-month period, and the water potential was measured over a two-year period. These data were related to precipitation, water availability in the soil and photoperiod. Seven deciduous species exhibited low wood density (DLWD,?<0.5?g?cm?3), high capacity of water storage in the stem (until 250?% of the dry weight) and high water potential during the year, as opposed to 15 deciduous species that showed high wood density (DHWD,?≥0.5?g?cm?3). Leaf flush, flowering and the fruiting of DHWD species were related to precipitation, whereas these phenological events occurred at the end of the dry season and/or the beginning of the rainy season for DLWD species and were related to the photoperiod. The two evergreen species showed variations of water potential that were intermediate between those of DHWD and DLWD deciduous species, leaf flush during the dry season and flowering at the end of dry season. These results suggest the existence of three functional groups: evergreen species, DHWD deciduous species and DLWD deciduous species.  相似文献   

10.
This paper examines the abundance and Aboriginal use of botanical non-timber forest products in the Gwich’in Settlement Area in the Northwest Territories, Canada. Informants indicated that wild berries are important to Gwich’in diets and an important factor in culture and traditional land use. People collected mostly cloudberries (Rubus chamaemorus), blueberries (Vaccinium uliginosum), and lingonberries (Vaccinium vitisidaea). The total quantities collected were estimated to be greater than other published accounts of berry gathering by northern Aboriginal peoples in North America. The total collected by the 450 households in the year 2000 was about 16,000 L. Inventories of wild berries on the landscape suggest that substantial quantities could be collected for commercial production, although the between-year supply can show considerable variation.  相似文献   

11.
12.
The abundance and aggregation of eggs of Aedes aegypti L. and Aedes albopictus Skuse was evaluated in the municipalities of Cambé, Ibipor?, Jacarezinho, Maringá and Paranavaí, in the State of Paraná, Brazil by means of oviposition traps. Of the 225 installed traps, 100 were registered as positive for eggs; 4140 eggs were collected, thus demonstrating an highly aggregate distribution. Both species were registered in Cambé, Jacarezinho, Maringá and Paranavaí. Ae. albopictus was generally less abundant and was not present in Ibipor? nor in the oviposition traps of a second collection of Maringá. The relation between sexes for Ae. aegypti was approximately 1:1. In the comparison of the number of adults collected between the two species, a negative correlation was obtained in the samples of Maringá and Cambé, what was attributed the seasonality of these populations. The coexistence of these species indicates that both are under pressure by the control programs, therefore specific evaluations are necessary.  相似文献   

13.

During the Festival of Our Lady of Urkupin ¨ a, held every August in Quillacollo, Bolivia, an estimated half million pilgrims petition Our Lady for wealth and material goods. The festival has become a national event and now includes the participation of government officials, including the President, as well as widespread coverage by the media. The festival has also become a point of controversy and contestation over the meanings of Bolivian nationalism, commercialism, and economic development. These issues, as I will show, have been articulated through criticisms of the festival as being too sensuous and overly commercialized. Through an examination of media coverage of the festival of Urkupiña, this article focuses on the ways that "evils" of materialism and sensuality are represented visually. The Bolivian state and the Catholic Church have sought to define the meaning of the festival in terms of devotion and national identity while criticizing some festival practices associated with gaining wealth. Here I show how the folkloric and devotional elements of the festival are embodied in the dancers while the visual referent for the materialism of the festival is street vendors. I also discuss how the festival transforms the meanings of the ch'alla and other Andeanpractices that anthropologists have traditionally associated with resistance to capitalism (as found for example in the work of June Nash and Michael Taussig). The article concludes by noting that, rather than mapping these meanings ontogeneralized resistance, anthropologists must be prepared fully to engage contestations over devotion, material gain, sensuousness, and economic development. In short, we should also be prepared to dance with the devil.  相似文献   

14.
The microbial community of artisanal corn fermentation called Chicha were isolated, purified and then identified using protein profile by Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF) and confirmed by partial ribosomal gene sequencing. Samples from Chicha beverage were chemically characterized by gas and liquid chromatography (HPLC and GC-MS). Aerobic mesophilic bacteria (AMB) (35.8% of total of isolated microorganisms), lactic acid bacteria (LAB) (21.6%) and yeast (42.6%) were identified. Species of the genera Klebsiella, Bacillus, Staphylococcus, Micrococcus, Enterobacter, and Weissella were identified. Rhodotorula mucilaginosa, Lodderomyces elongisporus, Candida metapsilosis, and C. bohicensis were the yeasts found. The LAB isolates detected were responsible for the high concentrations of lactic acid found during the fermentation process (1.2 g L??1), which is directly related to the decrease in pH values (from 6.95 to 3.70). Maltose was the main carbohydrate detected during corn fermentation (7.02 g L??1 with 36 h of fermentation). Ethanol was found in low concentrations (average 0.181 g L??1), making it possible to characterize the beverage as non-alcoholic. Twelve volatile compounds were identified by gas chromatography; belonging to the groups acids, alcohols aldehydes, acetate and others. MALDI-TOF was successfully used for identification of microbiota. Weissella confusa and W. cibaria were detected in the final product (after 36 h of fermentation), W. confusa is often classified as probiotic and deserve further application studies.  相似文献   

15.
Native to Brazil,Schinus terebinthifolius Raddi, of the family Anacardiaceae, has been commonly cultivated in Florida for over 50 years as a dooryard ornamental. Use of its sprays of showy red fruits for Christmas decoration gave rise to the popular misnomer “Florida holly.” Too late it was found to become a large, spreading tree; aggressive seedlings began springing up near and far. Jungles ofSchinus have crowded out native vegetation over vast areas of Florida and the Bahamas, as in all the islands of Hawaii. When in bloom, the tree is a major source of respiratory difficulty and dermatitis; the fruits, in quantity, intoxicate birds and cause fatal trauma in four-footed animals. The abundant nectar yields a spicy commercial honey and beekeepers are opposed to eradication programs.  相似文献   

16.
Delphinium barbeyi is a common herbaceous wildflower in montane meadows at 2,900 m near the Rocky Mountain Biological Laboratory, and its flowers are important nectar resources for bumblebees and hummingbirds. During the period 1977-1999 flowering was highly variable in both timing (date of first flower ranged from 5 July to 6 August, mean=17 July) and abundance (maximum open flowers per 2Ƕ-m plot ranged from 11.3 to 197.9, mean=82). Time and abundance of flowering are highly correlated with the previous winter's snowpack, as measured by the amount of snow remaining on the ground on 15 May (range 0-185 cm, mean=67.1). We used structural equation modeling to investigate relationships among snowpack, first date of bare ground, first date of flowering, number of inflorescences produced, and peak number of flowers, all of which are significantly correlated with each other. Snowpack depth on 15 May is a significant predictor of the first date of bare ground (R2=0.872), which in turn is a significant predictor of the first date of flowering (R2=0.858); snowpack depth is also significantly correlated with number of inflorescences produced (R2=0.713). Both the number of inflorescences and mean date of first flowering are significant predictors of flowers produced (but with no residual effect of snowpack). Part of the effect of snowpack on flowering may be mediated through an increased probability of frost damage in years with lower snowpack - the frequency of early-season "frost events" explained a significant proportion of the variance in the number of flowers per stem. There is significant reduction of flower production in La Niña episodes. The variation in number of flowers we have observed is likely to affect the pollination, mating system, and demography of the species. Through its effect on snowpack, frost events, and their interaction, climate change may influence all of these variables.  相似文献   

17.
Life-history parameters of pterosaurs such as growth and ontogenetic development represent an enigma. This aspect of pterosaur biology has remained perplexing because few pterosaur taxa are represented by complete ontogenetic series. Of these, Pterodaustro is unique in that besides being represented by hundreds of individuals with wing spans ranging from 0.3 to 2.5m, it includes an embryo within an egg. Here we present a comprehensive osteohistological assessment of multiple skeletal elements of a range of ontogenetic sizes of Pterodaustro, and we provide unparalleled insight into its growth dynamics. We show that, upon hatching, Pterodaustro juveniles grew rapidly for approximately 2 years until they reached approximately 53% of their mature body size, whereupon they attained sexual maturity. Thereafter, growth continued for at least another 3-4 years at comparatively slower rates until larger adult body sizes were attained. Our analysis further provides definitive evidence that Pterodaustro had a determinate growth strategy.  相似文献   

18.
The fascination of Antarctic scientists with Antarctic krill and their capabilities has a long and varied history, and prompted many scientists to maintain and manipulate krill under laboratory conditions. Starting in the Discovery era with Mackintosh at the King Edward Point labs on South Georgia, 1930, scientists have collected krill from sailing vessels, small boats, inflatable zodiacs and large ice-breaking vessels. Krill have been maintained in small and large jars, deep rectangular tanks, large round tanks and in flow-through and recycling systems. They have been maintained both on board research vessels and in laboratories, in flowing seawater systems at ambient conditions and in temperature-controlled environmental rooms. A few researchers have transported living krill back to their home laboratories, for example tropical laboratories in Japan (Murano) and Australia (Ikeda), temperate laboratories (Nicol) in Australia, a northern European laboratory in Germany (Marschall) and a sunny maritime laboratory in California (Ross and Quetin). The goals have been varied: short-term experiments to understand in situ physiological rates, long-term experiments to test the effects of manipulations or controlled changes in environmental conditions, and behavioral responses. We take you on a brief historical tour as we trace the lineage of modern day research on living Antarctic krill.  相似文献   

19.
The zooplankton composition is studied in the thermokarst, glacial and meteorite lakes, channels, former riverbeds, and hollows in the basin of Anadyr’. We found 174 taxa: 78, Rotatoria, 55, Cladocera, and 41, Copepoda. The most diverse is the lake fauna: 51 taxa of Rotatoria, 48, Cladocera, and 37, Copepoda. The thermokarst Lake Maiorskoe hosts 68 taxa: 31, Rotatoria, 14, Cladocera, and 23, Copepoda, wheras the cold ultraoligotrophic Lake El’gygytgyn features only one species of Cyclop of the group scutifer Cyclops neymanae Strel., and Rotatoria and Cladocera are present as allochtonous forms. The Copepoda illustrate the relations of the Anadyr’ fauna with those of Europe, North America, and Japan.  相似文献   

20.
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