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1.
IMpRH server: an RH mapping server available on the Web   总被引:9,自引:0,他引:9  
SUMMARY: The INRA-Minnesota Porcine Radiation Hybrid (IMpRH) Server provides both a mapping tool (IMpRH mapping tool) and a database (IMpRH database) of officially submitted results. The mapping tool permits the mapping of a new marker relatively to markers previously mapped on the IMpRH panel. The IMpRH database is the official database for submission of new results and queries. The database not only permits the sharing of public data but also semi-private and private data.  相似文献   
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The purpose of this study is to evaluate the efficiency of hybrid constructed wetlands (HCWs) in a rural mountainous area. The experiment was set up in small rural community named Tidili within the region of Marrakech, Morocco. The wastewater treatment plant was composed of three vertical flow constructed wetlands (VFCWs) working in parallel, followed by two parallel horizontal-subsurface flow constructed wetlands (HFCWs), with hydraulic loading rates of 0.5 and 0.75 m3/m2.d, respectively. The two units were planted with Phragmites australis at a density of 4 plants/m2. Wastewater samples were collected at the inlet of the storage tank and at the outlet of the whole system (VFCWs, HFCWs) stages. The main removal percentages of total suspended solids (TSS), biochemical oxygen demand measured in a 5-day test (BOD5), chemical oxygen demand (COD), total nitrogen, and total phosphorus were respectively 95%, 93%, 91%, 67%, and 62%. The system showed a very high capacity to remove total coliforms, fecal coliforms, and fecal streptococci (4.46, 4.31, and 4.10 Log units, respectively). Artificial neural networks (ANNs) were used to model the quality parameters (TSS, BOD5, COD) and total coliforms and fecal streptococci. Based on the obtained results, the ANN model could be considered as an efficient tool to predict the studied phytoremediation performances using HCWs.  相似文献   
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Floating seaweeds play an important role as a habitat for many animals accompanying or attaching to them in offshore waters. It was in 2000 that the first report described abundant distributions of floating seaweeds in offshore waters in the East China Sea in spring. Young individuals of the yellowtail Seriola quinqueradiata are captured for aquaculture purposes from floating seaweeds in the East China Sea. Therefore, a sound understanding of the distributions of floating seaweeds in the East China Sea is needed. Detailed information is especially important during the late winter to early spring, which corresponds to the juvenile period of the yellowtail. Thus, field surveys using R/V Tansei-Maru were conducted in the Japanese Exclusive Economic Zone in the East China Sea from late winter to early spring in 2010 and 2011. We obtained positions of the vessel by GPS and transversal distances from the vessel to a raft by visual observation. Distance sampling method (Thomas et al. 2010) was applied to estimation of floating seaweed densities (rafts km?2). Seaweed rafts were also randomly sampled using nets during the research cruises. In the East China Sea, seaweed rafts were distributed mainly on the continental shelf west of the Kuroshio, especially in waters between 26° N and 30° N. Collected rafts consisted of only one species, Sargassum horneri (Turner) C. Agardh. Taking into account surface currents and geographical distribution of S. horneri, it is estimated that these floating seaweeds originated from natural beds along the coast between mid and south China. Considering the approximate travel times, it is suggested that floating patches are colonized by yellowtails early on during their trips, i.e., close to the Chinese coast.  相似文献   
5.

Background

Essential oils extracted from aromatic and medicinal plants have many biological properties and are therefore an alternative to the use of synthetic products. The chemical composition of essential oils from two medicinal plants (Eucalyptus globulus and E. lehmannii) was determined and, their insecticidal effects on the third and fourth larval stages of Orgyia trigotephras were assessed.

Results

Larvae were collected from Jebel Abderrahmane (North-East of Tunisia), conserved in groups of 50/box (21 × 10 × 10 cm) at a temperature of 25°C. Larvae were tested for larvicidal activities of essential oils. Each oil was diluted in ethanol (96%) to prepare 3 test solutions (S1 = 0.05%, S2 = 0.10% and S3 = 0.50%). Essential oils were used for contact, ingestion and Olfactory actions and compared to reference products (Bacillus thuringiensis and Decis). Olfactory action of essential oils shows that larvae mortality is higher than contact action, lower than ingestion action. MTM and FTM of S3 of E. lehmannii were respectively 1 h 32 min and 1 h 39 min are higher than those of E. globulus (MTM = 51 min and FTM = 1 h 22 min 34 sec). Contact action of E. lehmannii oil shows low insecticidal activity compared to E. globulus. MTM are respectively (1 min 52 sec and 1 min 7 sec), FTM are (2 min 38 sec, 1 min 39 sec), are the shortest recorded for S3, on the third stage of larvae. The fourth stage of larvae, MTM are (2 min 20 sec and 2 min 9 sec), FTM are (3 min 25 sec, 3 min 19 sec). Ingestion action of essential oils is longer than the contact action, since the time of death exceeds 60 minutes for all species.

Conclusion

Results shows that essential oils have a toxic action on nerves leading to a disruption of vital system of insects. High toxic properties make these plant-derived compounds suitable for incorporation in integrated pest management programs.  相似文献   
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Imposex occurrence in the changeable nassa Nassarius (Sphaeronassa) mutabilis (Linnaeus, 1758) was confirmed in the present study. Advanced imposex stages were discovered for the first time in this nassarid starting from the initial appearance of the vas deference sequence or the bud penis (VDS1), to the point where this duct reaches the vaginal opening (VDS4). Three types of imposex pathways were found for stage 1 (VDS1a, VDS1b and VDS1d), two for stage 2 (VDS2a and VDS2d) and stage 3 (VDS3a and VDS3b). Affected females were found in the three studied stations with imposex frequency ranging from 10.5 to 47.2%, VDSI from 0.1 to 0.8, FPL from 0 to 0.1 mm, RPLI from 0 to 0.9, and VDL from 0.2 to 1.3 mm. Organotins body burden ranged from 0.8 to 16 ng/g d.w. for MBT, 2.5–14.9 for DBT, and 3.7–14.4 for TBT. To our knowledge, this is the first detailed report on imposex in N. mutabilis suggests its inclusion to list of imposex-affected gastropods.  相似文献   
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The banded murex Hexaplex trunculus (Linnaeus, 1758) is a commercially exploited gastropod in the Mediterranean region including Tunisia where it has become an important fishery resource these last years. In the present investigation, some reproductive aspects of this species were described in the population of Boughrara lagoon based on macroscopic examination of the gonads (gonadic conditional indices) together with observation of the seasonal hypertrophy of the penis in males and capsule gland in females. This procedure of assessing reproductive activity was validated by field observations of copulation and spawning. Mature females were found during 10 months and mature males during 8 months being both frequent in January and February. Reproductive activity was slightly asynchronous between sexes with males reaching maturity before females. Gonadic release occurred earlier in males between January and March against February to April in females. These findings were in agreement with field observations of copulation in January and February and egg-capsule laying in late February and March. Hatching juveniles were observed in the field in April and May.  相似文献   
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Spawning, development and growth of Siphonaria pectinata in the laboratory were studied and described in detail during a one-year study period. Egg ribbons were observed in February, March, April, June, July, August and September, with a peak in number of ribbons per individual in July. On average, individuals laid 9.0 ± 5.1 egg ribbons at a spawning frequency of one egg ribbon day?1. The number of eggs per ribbon ranged from 752 to 50,400 depending on ribbon length. Embryonic development studied in February (13–15 °C), April (15–17 °C) and July (25–27 °C), reached hatching within 8–16 days with average larval lengths of 76.7 ± 5.9, 83.0 ± 11.3 and 78.3 ± 9.0 μm, respectively. Massive mortality was registered a few days after hatching, with larval longevity depending on the study period. Larval settlement occurred within 36–38 days after hatching, but only in the spawn deposited in February. Larval growth was slow during the first three weeks (18–26 μm week?1) and then accelerated until the sixth week (40–67 μm week?1). The present study contributes knowledge on the spawning, development and growth of S. pectinata, an alien species recently spreading throughout the Tunisian coast.  相似文献   
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In the following study, we investigate the effects of static magnetic field (SMF) (128 mT, 1 h/day during 5 or 15 consecutive days) on anthropometric parameters, glucose and lipid metabolism in rats. Exposure to SMF during 5 days induced a decrease (-8%, p < 0.05) in relative liver weight and serum insulin concentration (-56%, p < 0.001), while blood glucose level was increased (+10%, p < 0.001). By contrast, the same treatment failed to alter body weight, relative kidney weight and levels of lactate, cholesterol, triglycerides and phospholipids. Exposure to SMF during 15 days induced a decrease (-15 %, p < 0.001) in body weight, liver weight (-15 %, p < 0.05), insulin concentration (-63%, p < 0.001), plasmatic lactate level (-55%, p < 0.05) and increased glucose (+24%, p < 0.001), cholesterol (+30%, p < 0.01,) and phospholipids levels (+58%, p < 0.001), whereas, triglycerides decreased (-28%, p < 0.001). These results showed that SMF effects on glucose and lipid metabolism are time-dependent.  相似文献   
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