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1.
The olive tree had been domesticated during the early Neolithic in the Near East, and more than 1000 different cultivars have been identified to date. However, examples of wild olive trees (Olea europaea oleaster) can still be found in the Mediterranean basin. Evidence of oleaster use for oil production can be found in historical and sacred texts, such as the Odyssey, the Holey Koran, and the Holey Bible. While the nutritional and healthful properties of olive oil are actively being explored, there are no data on the human actions of oleaster oil. Therefore, we investigated the effect of prolonged, i.e., 1 month, consumption of oleaster oil on the lipid profile of a 40 healthy Algerian subjects (aged 27.9 ± 3.85 years), as compared to nonconsumers from the same area. Plasma urea, creatinine, and uric acid concentrations and glycemia did not significantly differ, at the end of the study, between controls and oleaster-oil-supplemented subjects. Conversely, we recorded significant decreases of plasma triglyceride concentration (-24.8%; p < 0.05), total cholesterol (-12.13%; p < 0.05), and low-density lipoprotein-cholesterol (LDL-C) (-24.39%; p < 0.05) in oleaster-oil-treated subjects. Concomitantly, high-density lipoprotein-cholesterol (HDL-C) concentrations were significantly increased (17.94%; p < 0.05) by oleaster oil administration. In conclusion, we show that oil obtained from feral olive trees, i.e., oleasters, improves the plasma lipid profile of healthy volunteers.  相似文献   
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3.
In a topical bioassay with pupae and adults of the mealwormTenebrio molitor (Coleoptera: Tenebrionidae), an important pest in stored products worldwide, three insect growth inhibitors (IGRs) were tested: the two chitin synthesis inhibitors diflubenzuron and flucycloxuron, and the ecdysone agonist halofenozide (RH-0345). To address differences in toxicity, we determined with the use of a14C-labeled isotope, the pattern of absorption through the cuticle and then the distribution in the different body tissues of gut, hemolymph, integument and reproductive organs (ovaries, testis). The rate of absorption through the cuticle was highest for flucycloxuron, and this concurred with its high toxicity. In general, the patterns of absorption followed a similar trend in young and old pupae and in the adult stage. Accumulation in the reproductive system of females and males was relatively high, which may explain the strong reproductive effects of the IGRs tested. In addition, we recorded large differences in the clearance of insecticide from the insect bodyvia the excrements, with the chitin synthesis inhibitors exhibiting higher rates than halofenozide.  相似文献   
4.
Olive oil mill wastewater (OMW) generates a wide variety of pollutants depending on the production process and other factors such as olive varieties and cultivation system. Efforts to mitigate the impact of these effluents in the environment have been made by developing more efficient treatment systems in terms of removal of chemical oxygen demand (COD), color, organic compounds, and toxicity. This study is the first that reports the potential of a treatment of OMW by biocomposites of silica?Calginate?Cfungi (Pleurotus sajor caju and Trametes versicolor). The treatment by biocomposites can be considered as a three-step process responsible for the removal of the compounds: (1) adsorption of reactants on the monolithic structure and diffusion to the biological active sites, (2) biodegradation by the fungi, and (3) diffusion of the products resulting from the biodegradation. Both treatments tested showed potential capacity to remove organic compounds, color, COD, and toxicity. The T. versicolor biocomposites were the most effective and responsible for the reduction in color (from 38.4 to 44.9?%), COD (from 42.8 to 63.8?%), and total phenolic content (from 85.3 to 88.7?%) after 29?days of treatment. The toxicity reduction on Portuguese OMW was minimal, but the use of composites on the Moroccan OMW caused a 9.5- to 19-fold reduction in toxicity. Furthermore, the biocomposites showed potential for re-utilization for more 29?days of treatment.  相似文献   
5.
Abstract

The objective was to evaluate the economic feasibility of introducing fish culture into irrigated cotton production on farms in central Arizona. Water as a production variable was calculated only for the additional quantity required to keep water in the ditches during the growing season for fish. Raising tilapia in pulsed‐flow culture systems on Arizona cotton farms is economically feasible. Production function estimates indicate that profits can be increased through additional use of feed. At any ditch capacity, a density of six fish/m3 provided the optimal economic results, as the value of marginal product (VMP) equalled the price of fingerlings stocked/m3. This optimum fish production scenario would increase the net income for a typical irrigated cotton farm by 7 per cent. Increasing the initial size of the fingerlings improved the percentage of fish reaching marketable size and perhaps will increase economic returns, a question to be studied by future research.  相似文献   
6.
Rickettsioses and bartonelloses are arthropod-borne diseases of mammals with widespread geographical distributions. Yet their occurrence in specific regions, their association with different vectors and hosts and the infection rate of arthropod-vectors with these agents remain poorly studied in South-east Asia. We conducted entomological field surveys in the Lao PDR (Laos) and Borneo, Malaysia by surveying fleas, ticks, and lice from domestic dogs and collected additional samples from domestic cows and pigs in Laos. Rickettsia felis was detected by real-time PCR with similar overall flea infection rate in Laos (76.6%, 69/90) and Borneo (74.4%, 268/360). Both of the encountered flea vectors Ctenocephalides orientis and Ctenocephalides felis felis were infected with R. felis. The degrees of similarity of partial gltA and ompA genes with recognized species indicate the rickettsia detected in two Boophilus spp. ticks collected from a cow in Laos may be a new species. Isolation and further characterization will be necessary to specify it as a new species. Bartonella clarridgeiae was detected in 3/90 (3.3%) and 2/360 (0.6%) of examined fleas from Laos and Borneo, respectively. Two fleas collected in Laos and one flea collected in Borneo were co-infected with both R. felis and B. clarridgeiae. Further investigations are needed in order to isolate these agents and to determine their epidemiology and aetiological role in unknown fever in patients from these areas.  相似文献   
7.
Since 1960, the steppe regions of North Africa have been subject to an increasing desertification, including the degradation of traditional pastures. The initially dominant species(Artemisia herba-alba, Lygeum spartum and Stipa tenacissima) declined and were progressively replaced by other species(Atractylis serratuloides and Salsola vermiculata) that are more tolerant to the new conditions. It is not clear whether these changes are due to anthropogenic reasons or climatic determinism. We have carried out a statistical analysis of the climate to detect putative rainfall changes during the 20~(th) century in the Algerian steppes based on data from 9 meteorological stations, including 2 Saharan stations(El Oued and Touggourt), 3 pre-Saharan stations(Biskra, Laghouat and Ain Sefra) and 4 steppe stations(Djelfa, Saida, Méchéria and El-Bayadh) located in the arid high plains, which represent the bioclimate diversities of the region. Previous studies suggested that significant rainfall changes for the 20~(th) century only had records in the south of the Oran region. Most of the studies, however, looked at restricted territories over limited periods, and did not integrate the rainiest period 2004–2014. Our work is designed to integrate all the longest time series of meteorological data available for the steppe regions of Algeria. Our results confirm the spatial rainfall distribution(significant rainfall changes only recorded in the southwestern region) evidenced by previous studies, and reveal a decreasing rainfall gradient from northeastern to southwestern Algeria. Moreover, the results reveal a trend of significant decrease of rainfall in the southern Oran region, marked by two drought periods in 1980–1985 and 1999–2003. However, with the exception of the southwestern region, rainfall overall has not declined since the beginning of the 20~(th) century. While less marked in other regions, the drought appear to have affected all territories of the Algerian steppe. Consequently, our study implies that the climate was not a leading influence in the on-going degradation of the vegetation cover of steppe landscapes. Such a vegetation evolution thus appears to be have been determined more by human activities than by climate forcing.  相似文献   
8.
In this work, electrospinning of poly(lactic acid) (PLA), chitosan and their blends has been investigated, and nanofibers with a diameter ranging from 90 nm to 1.9 microns were produced and used as carriers for immobilization of the phospholipase A1. A strong influence of chitosan (CS) and the solvent trifluoroacetic acid (TFA) on the morphology, distribution of the nanofibers diameter and on their hydrophobicity was observed. The yield of phospholipase A1 (PLA1) on non-woven fibers was evaluated using the method of Bradford. Their activities and their reutilisability were assessed titrimetrically using soybean lecithin as substrate. The results showed that the degree of immobilization on the non-woven fibers of pure PLA and mixtures PLA/CS4 and PLA/SC6 are 73, 54, 45 % respectively and can be reused up to 4 cycles without significant loss of enzyme activity. Moreover, a remarkable improvement of the activity of phospholipase A1 on non-woven based on pure PLA fibers was observed, indicating that most of the enzymes were probably in their active form.  相似文献   
9.
The ethereal extract of the roots of Opopanax chironium yielded peucelinenoxide acetate (1), a new natural product with an irregular diterpene skeleton, besides the known coumarins gaudichaudin, columbianadin, peucedanin and officinalin isobutyrate.  相似文献   
10.

Purpose

Ichkeul National Park, NW Tunisia, is a UNESCO Biosphere Reserve. Garaet El Ichkeul Lake is known for its seasonal variability in water level and salinity. In recent decades, the waterbody has been affected by the construction of new hydraulic structures. To reduce the impacts of dams and to maintain the sustainability of the ecosystem, a sluice was built at the outlet of the lake, and it operated for the first time in 1996. This paper describes an investigation of recent sedimentation dynamics in Ichkeul Lake, determined by radiometric dating of sediment cores.

Materials and methods

A sediment core was collected with a UWITEC gravity corer at the deepest, central part of the lake in August 2009. Specific activities of unsupported lead-210 (210Pb) and caesium-137 (137Cs) were measured in the core, enabling calculation of recent sediment accumulation rates (SAR). Published radiometric data from nearby sediment cores, collected in 1997 and 1982, provide a comparison.

Results and discussion

The measured excess 210Pb inventory was 5300?±?500?Bq?m?2, leading to an estimation of constant flux of 165?±?16?Bq?m?2?yr?1, a value higher than the best estimate for local atmospheric fluxes (123?±?12?Bq?m?2?yr?1) and the flux estimated from the core collected in 1982 (48?Bq?m?2?yr?1). The 137Cs inventory was 3550?±?120?Bq?m?2, two times higher than the historical 137Cs atmospheric deposition in the area. The 137Cs profile displayed a distinct peak, but the 137Cs depth-distribution did not follow the pattern expected from atmospheric deposition. Application of the constant rate of supply (CRS) model, with the reference point method, produced a chronology and SAR values comparable to those found in previous work. The whole 137Cs profile was quantitatively reconstructed from the historical records of atmospheric deposition, using the system-time-averaged (STA) model.

Conclusions

The CRS and STA models provide consistent sediment accumulation results for the whole data set, considering the time resolution of the chronology (~6?years) and analytical uncertainties. Results from cores sampled in 1982, 1997 and 2009 reveal an increasing SAR trend, from ~0.25?g?cm?2?yr?1 in the early 1940s to ~0.67?g?cm?2?yr?1 at present. In the 13?years since installation of sluice gates at Tinja, SAR in the central Ichkeul Lake has not declined. Thus, if siltation continues at the present rate, shallowing of the lake will seriously affect the hydromorphology and ecology of this important lake.  相似文献   
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