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41.
The Gorka pit lake was formed in an inactive Jurassic limestone quarry after cessation of open-pit dewatering. The main problem of the water quality in this area is linked to a large volume of extremely alkaline leachate disposed in the flooded quarry. The lake is meromictic due to a large density contrast between shallow and deep water layers. Water in the lake is of the Na?CCO3?COH type, pH is in the range from 11.5 to 13.3, and there are high concentrations of sulfate and several toxic elements (Al, As, Cr, Mo, P, and V). The chemical composition of the extremely alkaline leachate was formed as a result of the groundwater interaction with the industrial red mud wastes containing 5?C10 wt.% of sodium carbonate. There is a trend of increasing concentrations and pH values with depth, mainly due to the in-gassing of atmospheric CO2 into the surface layer and due to density stratification in the water column. Similar stratification is observed in groundwater wells around the lake. High dissolved concentrations of oxyanionic contaminants such as As, Cr, and V are caused by their high mobility and desorption under extremely alkaline conditions. In spite of reducing conditions at the bottom of the lake, caused by high concentrations of dumped organic matter, sulfate behaves conservatively because sulfate reducing bacteria do not survive in this pH range.  相似文献   
42.
The aim of this investigation was to determine the prevalence of coccidian infections in suckling piglets and sows in Poland. The research was carried out in 14 out of 16 Polish provinces in the years 2003-2005. The investigation was conducted on three types of farms: large farms (>100 sows), medium farms (25-100 sows) and small farms (<25 sows). Diarrhoea of unweaned piglets was observed on all the examined farms. Overall, 780 litters of suckling piglets from 104 farms and 267 mother sows were examined. The faeces were analyzed with the modified McMaster method. Isopsora suis was found in 217 (27.8%) litters from 70 (66.7%) farms. Eimeria spp. was detected only in 20 (2.6%) litters from 12 (11.5%) farms. On the large farms I. suis infection was detected in 31.7% of litters whereas Eimeria spp. in 1.4% of them. On the medium sized farms I. suis was found in 18.1% of litters and Eimeria spp. in 0.6%. On the small farms I. suis was detected in only 13.2% of litters, whereas Eimeria spp. in as many as 28.9%. I. suis and Eimeria spp. oocysts were found in 18 (6.7%) and 16 (6%) sows respectively. From 72 sows producing I. suis infected piglets only 12 (16.7%) shed I. suis oocysts and as little as 4 (5.6%) shed Eimeria oocysts. In the remaining 56 sows (77.8%) no cases of coccidian infections were detected. The results of this investigation demonstrate the high prevalence of I. suis in suckling piglets on the large swine farms in Poland.  相似文献   
43.
Journal of Soils and Sediments - This paper investigates the morphological and location features influencing the sediment texture of small reservoirs located within the embanked floodplain of a...  相似文献   
44.
The bioactivity of two kiwifruit’s cultivars growing under organic and conventional conditions were studied and compared. The bioactive compounds were extracted with water and ethanol using similar conditions which are applied in pharmaceutical applications and for daily fruit consumption such as tea drink. Antioxidant radical scavenging assays [ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC); 2, 2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)], fourier transform infrared (FT-IR) and ultraviolet spectroscopy, two (2D-FL) and three-dimensional (3D-FL) fluorometry were used for the detection of biologically active metabolites derived from kiwifruits (total phenols, flavonoids, chlorophylls, carotenoids and ascorbic acid). The correlation between the total phenol content (TPC) and other bioactive compounds, and their total antioxidant capacities (TAC) was calculated for studied kiwifruit’s extracts. The interaction between drugs and human serum albumin (HSA) plays an important role in the distribution and metabolism of drugs. The properties of kiwifruit’s phenol extracts showed their ability to quench HSA, forming the complexes similar to the ones between the proteins and pure flavonoids such as quercetin. The cultivar ‘Bidan’ exhibited significantly higher TAC than the classic ‘Hayward’. In conclusion, for the first time ‘Bidan’ organic kiwifruit was analyzed and compared with widely consumed ‘Hayward’, using its bioactive and fluorescence properties. The influence of physiologically active kiwifruit’s compounds on human health, through our investigations in vitro and scientifically proven information, was explained. Relatively high content of bioactive compounds, high antioxidant and fluorescence properties of kiwifruit justify its use as a source of valuable antioxidants.  相似文献   
45.
In this study, different Polish cultivars of blue-berried honeysuckles (Lonicera caerulea L.), wild and bog bilberry, were analyzed for bioactive compounds. The chemical properties verified included composition of anthocyanins and other polyphenols, antioxidant activity, and profiles of antioxidants by HPLC postcolumn derivatization or TLC. The antioxidant activities of different blue-berried honeysuckle cultivars were similar to that of wild-growing bilberries (ranging from 170 to 417 μmol TE/g dm in ABTS and from 93 to 166 μmol TE/g dm in DPPH and Folin-Ciocalteu tests). The major anthocyanin in the blue-berried honeysuckle was cyanidin-3-glucoside, which constituted 84-92% of the total anthocyanins. The TLC and HPLC postcolumn antioxidant profiles indicated that anthocyanins are the major antioxidants in all berries studied. Wild berries and the cultivars of the blue-berried honeysuckles are also a similar source of such minerals as K, Mg, and Ca.  相似文献   
46.
Subunits of high molecular weight glutenins strongly influence wheat bread making quality and can be associated with important agronomic traits. Polish winter wheats show a significant quantitative dominance of the null allele over the coding alleles of the Glu-A1 locus. To identify the causes of such skewed distribution, 116 F5 lines obtained from six cross combinations were analyzed for their HMW glutenin subunits and 11 agronomic characteristics, such as plant height and uniformity, leaf blotch and leaf rust resistance, grain yield per plot, number of grains per ear, grain yield per ear, 1000 kernel weight, frost tolerance, total protein content and the SDS-sedimentation value. The SDS-sedimentation value, resistance to leaf blotch and frost tolerance showed statistically significant associations with the status of the Glu-A1 locus. It appears that chromosome 1A with the null allele at Glu-A1 carries a closely linked locus responsible for frost tolerance. With early strong selection for winter hardiness, the null allele of Glu-A1 becomes fixed in advanced breeding materials despite its strong negative impact on the end use quality.  相似文献   
47.
This research introduces a new share design (L-share) that reduces the undesired random soil movement, providing a more controlled disturbance of the upper soil layer. Purpose: The aim of this study was to evaluate draught forces and soil movements when operating the new share. Materials and Methods: Experiments were conducted in a laboratory set-up using a soil bin with a fine loamy soil texture. The soil was compacted to a bulk density of 1500?kg?m?3, with a penetration index of 486?kPa and a mean water content of 10%. The cultivation depths were 30, 50 and 70?mm and the operation speeds were 0.84, 1.67 and 2.31?m?s?1. Cubes were used to measure soil movement by recording the displacement from their initial positions. The soil surface and furrow profile were measured by using a 2D laser range scanner. Results: The results showed that increasing operation speed and cultivation depths generally increased draught forces and soil movement. Changing the cultivation depth from 30 to 50?mm resulted in a 63% greater longitudinal force (Fx), and 71% greater Fx when increasing the cultivation depth from 50 to 70?mm. Conclusion: The study showed that the new L-share mounted on a modified spring tine only causes minor soil movement and thereby minimising the undesirable soil movement.  相似文献   
48.
Polish garlic and white and red onions were subjected to blanching, boiling, frying, and microwaving for different periods of time, and then their bioactive compounds (polyphenols, flavonoids, flavanols, anthocyanins, tannins, and ascorbic acid) and antioxidant activities were determined. It was found that blanching and frying and then microwaving of garlic and onions did not decrease significantly the amounts of their bioactive compounds and the level of antioxidant activities ( P > 0.05). The HPLC profiles of free and soluble ester- and glycoside-bound phenolic acids showed that trans-hydroxycinnamic acids (caffeic, p-coumaric, ferulic, and sinapic) were as much as twice higher in garlic than in onions. Quercetin quantity was the highest in red onion among the studied vegetables. The electrophoretic separation of nonreduced garlic and onion proteins after boiling demonstrated their degradation in the range from 50 to 112 kDa.  相似文献   
49.
OBJECTIVE: Comparison of 2 methods of surgical management of cranial cruciate ligament (CCL) injury in large-breed dogs using a radiographic osteoarthrosis (OA) scoring system. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n=66). METHODS: Radiographs were evaluated from dogs weighing >/=22.7 kg, with surgical management of CCL rupture using extracapsular repair (ECR) or tibial plateau leveling osteotomy (TPLO). Radiographs were taken immediately before surgery and >/=12 months later. An OA score was assigned to each set of radiographs taken at the preoperative and final examinations by evaluating 32 specific features of stifle OA. The difference between preoperative and final OA scores were subtracted and 2 final score categories of a change 5 were created. A logistic regression model was used to evaluate the effect of right versus left pelvic limb, age, preoperative weight, postoperative weight, days from surgery until final radiographic recheck, cranial cruciate status at surgery, medial meniscus status at surgery, and ECR versus TPLO. RESULTS: The ECR group had 27 stifles (22 dogs) and the TPLO group had 52 stifles (44 dogs). ECR dogs had a preoperative weight of 33.4+/-9.3 kg (range 22.7-54.1 kg) and a preoperative OA score of 13.0+/-8.4 (range 1-34) compared with TPLO dogs that had a preoperative weight of 38.9+/-9.1 kg (range 25-63.9 kg) and preoperative OA score of 15.9+/-8.4 (range 4-44). Postoperative weights for ECR and TPLO dogs were 33.6+/-9 kg (range 21.8-54.6 kg) and 39.4+/-10.1 kg (range 24-72 kg), respectively. Final OA scores were: ECR dogs, 26.3+/-10.8 (range, 10-54); TPLO dogs, 23.3+/-9.5 (range, 12-50). Dogs with a final change in OA score of >/=6 were 5.78 times more likely to have had ECR compared with those that had TPLO as stabilization procedure (odds ratio=5.78; Log-likelihood test P-value=.025). Other dependent variables were not significant. CONCLUSIONS: Based on logistic regression analysis, dogs with larger OA score differences were 5.78 times more likely to have had ECR than TPLO. CLINICAL RELEVANCE: Prospective, randomized surgical trials with pre-defined objective measures would be required to further evaluate the clinical importance of these preliminary findings which suggest that TPLO may help stabilize the cranial tibial thrust as originally proposed.  相似文献   
50.
Thearubigins are the quantitatively major phenolic compounds in black tea, accounting for some 60-70% of the solids in a typical black tea infusion. MALDI-TOF mass spectra for caffeine-precipitated SII thearubigins (SII CTRs) from 15 different commercial teas support previous conclusions that SII CTRs are polyhydroxylated oligomers (rather than polymers) of catechins and catechin gallates in redox equilibrium with their quinone counterparts. Some 4500 peaks were revealed in a mass range from m/z 500 to 2100. Polyphenols are redox-susceptible and readily generate artifacts during MALDI-TOF analysis when the matrix is also redox-susceptible. Of the nine matrices evaluated, 3',4',5'-trihydroxyacetophenone (F) provided the best compromise between signal intensity and redox artifact formation.  相似文献   
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