Changes in surface water supply across Africa with predicted climate change   总被引：2，自引：0，他引：2  

de Wit M  Stankiewicz J 《Science (New York, N.Y.)》2006,311(5769):1917-1921

Across Africa, perennial drainage density as a function of mean annual rainfall defines three regimes separated by threshold values of precipitation. This nonlinear response of drainage to rainfall will most seriously affect regions in the intermediate, unstable regime. A 10% decrease in precipitation in regions on the upper regime boundary (1000 millimeters per year) would reduce drainage by 17%, whereas in regions receiving 500 millimeters per year, such a drop would cut 50% of surface drainage. By using predicted precipitation changes, we calculate that a decrease in perennial drainage will significantly affect present surface water access across 25% of Africa by the end of this century.  相似文献   

Dose-dependent influence of commercial garlic (Allium sativum) on rats fed cholesterol-containing diet     

Gorinstein S  Leontowicz M  Leontowicz H  Jastrzebski Z  Drzewiecki J  Namiesnik J  Zachwieja Z  Barton H  Tashma Z  Katrich E  Trakhtenberg S 《Journal of agricultural and food chemistry》2006,54(11):4022-4027

The aim of this investigation was to evaluate the dose-dependent influence of commercial garlic on rats fed cholesterol-containing diets. It was found that commercial garlic contains high concentrations of dietary fibers, microelements, and total polyphenols, and its total antioxidant capacity as determined by two independent assays [1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)] was similar to that of the original garlic samples. Wistar rats (35) were randomly divided into five diet groups, named control, Chol, Garlic500, Garlic750, and Garlic1000. Control rats were fed basal diet (BD), which included wheat starch, casein, soybean oil, and vitamin and mineral mixtures. To the BD of the Chol group was added 1% of cholesterol. To the BD of the other three groups (Garlic500, Garlic750, and Garlic1000) were added 1% of cholesterol and commercial garlic equal to 500, 750, and 1000 mg of raw garlic per kilogram of animal weight. After 4 weeks of the experiment only in rats from the Garlic500 group were a significant hindering in the rise in plasma lipids and also a significant hindering in a decrease of plasma antioxidant activity registered. A significant decrease in plasma circulating fibrinogen and an increase in the clotting time were found in the same group of rats (P < 0.05 in both cases). The fibrinogenolytic effect of garlic diets was visualized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In the fibrinogen fraction of Garlic500 the 66, 24, and 14 kDa protein bands were detected with weaker protein intensity than in the corresponding ones in the Garlic750 and Garlic1000 diet groups. In conclusion, the positive influences of commercial garlic on plasma lipids, proteins, antioxidant activity, and some indices of blood coagulation are dose-dependent. Therefore, commercial garlic (Elena, Zelazków, Poland) could be a valuable component of atherosclerosis-preventing diets only in optimal doses.  相似文献   

Environmental studies of agricultural soils in Poland     

Stuczynski  Tomasz  Rybicka  Edeltrauda Helios  Pechalski  Jacek 《Journal of Soils and Sediments》2003,3(4):254-255

Journal of Soils and Sediments -  相似文献   

Preliminary study of guard hair morphology in four dog breeds          下载免费PDF全文

Paweł Tumiłowicz  Agata Goliszewska  Jacek Arct  Katarzyna Pytkowska  Marcin Szczepanik 《Veterinary dermatology》2018,29(4):332-e116

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Impact of scale on morphological spatial pattern of forest   总被引：1，自引：1，他引：0  

Katarzyna Ostapowicz  Peter Vogt  Kurt H. Riitters  Jacek Kozak  Christine Estreguil 《Landscape Ecology》2008,23(9):1107-1117

Assessing and monitoring landscape pattern structure from multi-scale land-cover maps can utilize morphological spatial pattern analysis (MSPA), only if various influences of scale are known and taken into account. This paper lays part of the foundation for applying MSPA analysis in landscape monitoring by quantifying scale effects on six classes of spatial patterns called: core, edge, perforation, branch, connector and islet. Four forest maps were selected with different forest composition and configuration. The sensitivity of MSPA to scale was studied by comparing frequencies of pattern classes in total forest area for various combinations of pixel size (P) and size parameter (S). It was found that the quantification of forest pattern with MSPA is sensitive to scale. Differences in initial composition and configuration influence the amount but not the general tendencies of the variations of morphological spatial pattern (MSP) class proportions with scale. Increase of P led to data generalization resulting in either a removal of the small size features or their potential transformation into other non-core MSP classes, while an increase of S decreases the MSP core area and this process may transform small core areas into the MSP class islet. We established that the behavior of the MSPA classes with changing scale can be categorized as consistent and robust scaling relations in the forms of linear, power, or logarithmic functions over a range of scales.  相似文献   

General combining ability and heterosis regarding the phytochemical properties in strawberry (Fragaria × ananassa) hybrids          下载免费PDF全文

Elżbieta Kaczmarska  Jacek Gawroński  Ewa Jabłońska‐Ryś  Marta Zalewska‐Korona  Wojciech Radzki  Aneta Sławińska 《Plant Breeding》2017,136(1):111-118

Strawberries are a common and important fruit in human diet because of their high content of essential nutrients and beneficial phytochemicals, which have relevant biological activity in human health. In this study, six cultivars and 15 selected F₁ hybrids between S₄ inbred lines and tester (cv. ‘Dukat’) were evaluated in a field trial over a period of two consecutive years. The amounts of total anthocyanin, phenolics and vitamin C in fruits and antiradical activity were analysed. General combining ability (GCA) and mid‐parent heterosis were also determined for those characteristics. Among all the genotypes tested, the inbred lines of ‘Senga Sengana’ 17 showed the highest breeding value based on GCA for all studied traits. Estimated heterosis varied among genotypes tested. The highest heterosis in terms of vitamin C occurred in the offspring of clone 1387 18‐15 × ‘Dukat’, but with regard to phenols and antiradical activity in hybrid ‘Teresa’ 18‐15 with cv. ‘Dukat’. This study revealed that the differentiation in chemical composition of strawberry fruits between genotypes is clearly dependent on individual genotype combinations and demonstrated the presence of heterosis in phytochemical contents in some specific genotypic combinations.  相似文献   

Diet and water temperature affect growth and body deformities in juvenile tench Tinca tinca (L.) reared under controlled conditions          下载免费PDF全文

Rafał Kamiński  Justyna Sikorska  Jacek Wolnicki 《Aquaculture Research》2017,48(3):1327-1337

The experiment was designed to determine the combined effect of fish diet and water temperature on juvenile tench Tinca tinca (L.). Three diets were used: commercial dry diet for fish Aller Futura (diet F); frozen Chironomidae larvae (diet C); and Aller Futura substituted with Chironomidae at a ratio of 3:2 (dry weight; diet FC). Daily food rations and duration of the experiment were adjusted to temperatures of 20°C, 23°C and 26°C based on a correction factor q equal to 1.000, 0.779 and 0.609 respectively. The experiment lasted 92, 72 and 56 days for the respective temperatures. No mortality occurred. The highest relative growth rates were found at 26°C in diets F and FC. The lowest food conversion ratio of 1.12–1.22 (recalculated for dry weight of feed diet) was determined in fish fed diet F at 23°C and 26°C. A high value of condition index appeared to be the early warning of decreasing biological quality of fish and deformities. The lowest incidence of fish with deformities (IDef) was found in groups fed diet C (<1%), while the highest (90%) in fish fed diet F at 26°C. A lower share of dry diet in the fish food and a lower water temperature led to a lower IDef. Thus, amount of dry feed in fish diet was the major factor inducing body deformities, while water temperature only modified the effects of the dietary factor. Diet C at 23–26°C was the most cost‐effective of the tested combinations of diet and temperature.  相似文献   

Lactones 43. New biologically active lactones: β‐cyclocitral derivatives     

Marcelina Mazur  Witold Gładkowski  Magdalena Podkowik  Jacek Bania  Jan Nawrot  Agata Białońska  Czesław Wawrzeńczyk 《Pest management science》2014,70(2):286-294

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Hybrid performance and heterosis in strawberry (Fragaria × ananassa Duchesne), regarding acidity,soluble solids and dry matter content in fruits          下载免费PDF全文

Elżbieta Kaczmarska  Jacek Gawroński  Ewa Jabłońska‐Ryś  Marta Zalewska‐Korona  Wojciech Radzki  Aneta Sławińska 《Plant Breeding》2016,135(2):232-238

A top‐cross‐mating design among 29 S₄ inbred lines and tester (cultivar ‘Dukat’) was carried out to study their breeding value in terms of general combining ability (GCA). The objectives of this study were to evaluate the acidity, soluble solids and dry matter contents in fruits of progeny F₁ in comparison with S₄ inbred lines as well as the cultivars (S₀); identify strawberry genotypes with high value of GCA for use in cultivar development; and determine mid‐parent heterosis regarding S₄ inbred lines and cultivated strawberry. The 2‐year observations showed statistically significant differences between tested genotypes in terms of the studied traits. The highest breeding value based on GCA was estimated for Chandler 123‐5 for soluble solids and dry matter content, and Kent 7‐6 for acidity. Estimated mid‐parent heterosis had positive and negative values. The highest heterosis in terms of extract and dry matter content (26.71% and 17.50%, respectively) occurred in the offspring Chandler 123‐5 × ‘Dukat’, but as regards acidity in hybrid Chandler 123‐22 with cv. ‘Dukat’. The study of genetic divergence by dendrograms may help to identify parents suitable for obtaining hybrids with higher heterosis effects.  相似文献   

Seasonal changes of mercury speciation in the coastal sediments     

Jacek Bełdowski  Marta Szubska  Magdalena Bełdowska  Katarzyna Jankowska  Ewa Kotlarska  Bożena Graca 《Journal of Soils and Sediments》2018,18(12):3424-3436

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