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71.
Grynkiewicz M. Polkowska Ż Górecki T. Namieśnik J. 《Water, air, and soil pollution》2003,145(1-4):3-16
Using an atmospheric photochemical model, the photochemical ozonecreation potential (POCP) values of non-methane hydrocarbon(NMHC) species are studied under different NMHC/NOx ratios. The behavior of POCP values of NMHC changing with time is also discussed under the condition of higher NMHC/NOx ratios, referring to the situation of China. The following results can beobtained. Alkenes, high-reactivity alkanes and aromatics, andformaldehyde are the primary contributors of photochemicalozone; The POCP values of NMHC species vary withNMHC/NOx ratios systematically. The POCP values of highreactivity species decrease with NMHC/NOx ratio increasing,but the POCP values of low reactivity species changelittle. The POCP value for a given NMHC species varieswith time of photochemical reactions. The POCP values oflow reactivity species increase with time, but the POCPvalues of high reactivity species change little. NOx, alkenes,aromatics, and aldehydes have higher reactivity and shorterlifetimes, therefore their transportation distances arelimited and they mainly produce local pollution. Alkanes havelower chemical reactivity and longer lifetimes so that theycan transport farther distance from their sources. 相似文献
72.
Purpose
The intensive development of nanotechnology raises a question of the potential consequences of the presence of nanoparticles (NPs) in the different components of the environment, including sediments. The aim of this study was to evaluate the toxicity of nanoparticles of ZnO and Ni and their bulk counterparts in bottom sediments (SD1, SD2) with different properties collected from the Vistula River in Poland.Materials and methods
Sediment samples with NPs at a concentration of 100 mg kg?1 were incubated for 17 months in the dark or under a photoperiod of 12 h light/12 h dark. The Microtox® (bacteria, Vibrio fischeri) and OSTRACODTOXKIT F? (ostracods, Heterocypris incongruens) tests were used to evaluate toxicity. In addition, the contents of Zn and Ni were determined in extracts (H2O and CaCl2) of the bottom sediments.Results and discussion
The Zn concentration was much lower in the SD1 sediment with the addition of NPs/bulk particles (30–230 μg kg?1) compared to the SD2 sediment (280–1140 μg kg?1). The toxicity of ZnO and Ni was determined by the type of bottom sediment and the parameter studied. Both nano- and bulk-ZnO and Ni caused the mortality of H. incongruens at a level of 13.3–53.3 %. The influence of ZnO and Ni on the growth of H. incongruens was observed to be the opposite. ZnO resulted in growth stimulation, while Ni resulted in growth inhibition of H. incongruens. Both ZnO and Ni stimulated V. fisheri luminescence. In most cases, the incubation of ZnO and Ni under the photoperiod increased the toxicity or decreased the stimulation of V. fisheri bioluminescence and H. ingongruens growth compared to the dark-incubated sediments.Conclusions
The study provides new and important information on the ecotoxicological effects of ZnO and Ni nanoparticles in different sediments and under various environmental conditions that may be useful for the risk assessment of this new group of contaminants.73.
Katarzyna Ognik Ewelina Cholewińska Krzysztof Tutaj Monika Cendrowska-Pinkosz Wojciech Dworzański Anna Dworzańska Jerzy Juśkiewicz 《Journal of animal physiology and animal nutrition》2020,104(1):352-361
The aim of this experiment was to investigate whether the amount of Cu added to the diet of rats can be reduced without adversely affecting the antioxidant status of tissues and growth, and whether copper nanoparticles can be used for this purpose. For four weeks, four experimental groups of rats were fed diets with two dosages of added Cu (standard—6.5 or 3.25 mg/kg) in two forms (standard—CuCO3 or copper nanoparticles). Replacing the CuCO3 supplement with CuNPs resulted in a decreased lung weight and an increased Cu content in brain, kidney and lung, intensification of lipid peroxidation processes, and weakened antioxidant defence in the lungs and kidneys. This treatment also reduced the Cu content in heart, level of lipid oxidation in the liver and testes and improved antioxidant defence in the brain. Reducing the addition of Cu to the diet from 6.5 to 3.25 mg/kg reduced lung weight and increased lipid peroxidation in the liver, heart and lungs, and also weakened antioxidant defence in the lungs and testes. This treatment also weakened the lipid peroxidation process in the spleen, small intestine and brain and strengthened the antioxidant defence of the brain and kidneys. In conclusion, replacing CuCO3 with CuNPs and reducing the level of Cu in the diet of rats has a particularly unfavourable effect on the respiratory system, causing adverse changes in the lungs. However, these treatments have a clearly positive effect on the redox status of the liver and brain. 相似文献
74.
B. Króliczewska D. Miśta W. Zawadzki A. Wypchło J. Króliczewski 《Journal of animal physiology and animal nutrition》2011,95(1):114-124
We studied the effects of Scutellaria baicalensis root on blood parameters and antioxidant enzyme activities in rabbits fed a high‐cholesterol diet. Thirty‐two New Zealand White rabbits were divided into four groups of eight animals each. They were fed a standard diet (C group), a diet with a 1% pure cholesterol supplement (CH group), a diet with a 1% pure cholesterol supplement and a 9% skullcap root supplement (CH + SR group), or a diet with a 9% skullcap root supplement (SR group). After 6 weeks, the rabbits fed the high‐cholesterol diet had significantly decreased RBC and Hb levels and significantly increased MCV, MCH and Fe levels (p ≤ 0.05). The skullcap root supplement had no adverse effects on the haematological parameters. The values for RBC, Hb, HCT, MCV, MCH and MCHC were similar in the skullcap root‐treated and control rabbits. We also observed a remarkable elevation in the serum TC, LDL and TG levels at the end of the 6‐week period. The rabbits fed the cholesterol diet showed decreased activity of the erythrocyte GSH‐Px compared with the rabbits fed the basal diet. The GSH‐Px activity was significantly higher in the rabbits fed the CH + SR diet than in those on the CH diet. The erythrocyte SOD activity was also significantly decreased in the rabbits on the CH diet. However, the CH + SR group rabbits showed significantly enhanced erythrocyte SOD activity. The SOD level in the CH + SR rabbits was 34.91 U/ml, which was a 23% increase (p ≤ 0.05) in relation to the results for the CH group and only 15% diminished in relation to the control group. These results suggest that the dietary supplementation of skullcap root may improve rabbit antioxidant systems and protect against the risks from a high‐cholesterol diet. 相似文献
75.
Analysis of integrins and vascular endothelial growth factor isoforms mRNA expression in the canine uterus during perimplantation period 总被引:1,自引:0,他引:1
Bukowska D Kempisty B Jackowska M Woźna M Antosik P Piotrowska H Jaśkowski JM 《Polish journal of veterinary sciences》2011,14(2):253-258
Integrins are the major receptors within the extracellular matrix (ECM) that mediate several functions connected with cell life and metabolism, such as cell adhesion, migration, cytoskeletal organization, proliferation, survival, and differentiation. A vascular endothelial growth factor (VEGF) is one of the most important angiogenic factors. It has been suggested that the expression of this gene may play crucial physiological roles in reproductive organs. All investigated endometrial tissues were isolated on day 10-12 after mating. Control bitches, used in this study, were in metestrus, which was determined according to the vaginal cytology and progesterone level in blood. Early pregnancy was verified by flushing the uterine horns with PBS. Total RNA was isolated from the bitches endometrium by means of the Chomczyński and Sacchi method, treated by DNase I, and reverse-transcribed into cDNA. A quantitative analysis of integrins alpha2b, beta2 and beta3, VEGF 164, 182 and 188 cDNA was performed by RT-PCR. In results we have shown an increased expression of all investigated genes (integrins alpha2b, beta2 and beta3, VEGF 164, 182, and 188) in pregnant bitches uterus as compared to non-pregnant females (P < 0.001). Our results indicated that the expression of genes encoding integrins and vascular endothelial growth factors is different in relation to the time of the embryo implantation and it is increased in the first period of this process. This may be associated with the induction of specific mechanisms responsible for receptivity of uterus following the embryo attachment. In addition, all of investigated genes are up-regulated in a pregnancy-specific manner and the increased expression of these genes may regulate the uterus function during the implantation of canine embryos. 相似文献
76.
Leszek Lenc Hanna Kwaśna Czesław Sadowski 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(4):603-620
Microbial communities in the root, rhizoplane, and rhizosphere and non-rhizosphere soil in potato, in organic and integrated
production systems, were compared at the emergence and flowering phases of plant development. Microorganisms were identified
on the basis of their morphology. The dominant groups included Clonostachys + Gliocladium + Trichoderma, Fusarium + Gibberella + Haematonectria + Neonectria, Paecilomyces, Penicillium and Phoma. Microbial density at the flowering phase was often significantly greater in roots and non-rhizosphere soil than in the rhizoplane
and rhizosphere. Diversity of the communities often remained stable or was greater at the emergence phase. The density of
bacteria changed with time. The density of Pseudomonas often decreased while Streptomyces significantly increased with time. Changes in densities of pathogens and antagonists decreased the suppressiveness of the
habitat towards soil-borne potato pathogens at the flowering phase. The study contributes information that will help to: (a)
understand the epidemiology of some potato diseases, (b) make decisions on the economic and ecological aspects of chemical
control in potato, (c) develop strategies for manipulation of the soil microbial environment as a viable crop management technique,
and (d) develop prognosis models for potato diseases in central Europe. 相似文献
77.
Robert Klewicki Dorota Konopacka Małgorzata Uczciwek Zbigniew Irzyniec Ewelina Piasecka Catherine Bonazzi 《The Journal of Horticultural Science and Biotechnology》2013,88(6):75-79
SummaryThe aim of our work was to measure sorption isotherms on freeze-dried and convectively-dried fruits (apple cv. Idared; sour cherry cv. English Morello; blackcurrant cv. Tiben), previously osmotically dehydrated in fructo-oligosaccharide solution, or concentrated apple juice. Isotherms were fitted using the Guggenheim-Anderson-de Boer Model. In none of the cases studied was isotherm non-continuity in the vicinity of the initial value of aw observed. All isotherms, classified as type III, demonstrated an increase in the equilibrium water content, along with an increase in water activity. A higher water content was observed in lyophilised material compared to material dried by convection. The water content in the monolayer (100 g?1 dry matter) ranged from 12.0 g for dried apple, to 17.0 g for dried sour cherry. These values can be considered as optimal in order to ensure safe storage conditions. The dried fruits should therefore be kept in a water activity range of 0.45 – 0.54 for lyophilised, and 0.46 – 0.63 for convectively-dried material. 相似文献
78.
The effect of chemical composition of starch samples derived from selected wheat cultivars harvested in different years (lipid content, amylose–lipid complex (AML) content, amylose concentration and the degree of starch damage) on physicochemical properties of glucose syrups produced from these starches was determined. It was found that glucose syrups obtained from the same wheat cultivar but harvested in different years displayed different physicochemical attributes such as concentration of reducing compounds, rate of filtration and coefficients of colour and transparency. Besides, the analyses showed that AML changed their form from amorphous to crystalline during enzymatic starch liquefaction by α-amylase. This in turn rendered starch less susceptible to enzymatic digestion and affected physicochemical features of glucose syrups. Presented results provide evidence that not only the total concentration of lipids and AML but also the AML polymorph present in starch hydrolysates (on completion of starch liquefaction) have an impact on quality of glucose syrups. 相似文献
79.
Penicillium adametzii significantly inhibited the growth of Heterobasidium annosum sensu stricto on 2% potato dextrose agar after 10 days at 20–25°C. Chloroform extracts from P. adametzii culture filtrate and from culture grown on rice often decreased the dry weight of Armillaria colony and diameter of Heterobasidion colony in vitro. The effect depended on species and isolate of Armillaria, Heterobasidion and P. adametzii and concentration of the extract. Higher concentration of chloroform extract increased the dry weight of stems and roots of Pinus sylvestris plants inoculated with either of two isolates of Armillaria ostoyae and one isolate of Armillaria gallica. Lower concentrations of chloroform extract increased the dry weight of stems and roots of P. sylvestris inoculated with another isolate of A. gallica. Culture filtrate of P. adametzii decreased the length of necrosis on P. sylvestris stem inoculated with either of two of four isolates of H. annosum s.s., but if applied 1 month before inoculation, it increased the length of necrosis caused by another H. annosum s.s. isolate. Twenty fractions from the P. adametzii chloroform extract were separated by thin layer chromatography. Carboxylic acids, flavonoids and glycosides were detected in chloroform extract of P. adametzii by high performance liquid chromatography/mass spectrometer analysis. This is the first report of interactions between P. adametzii and either Armillaria or Heterobasidion with P. sylvestris. 相似文献
80.
Epidemiological features of Morel's disease in goats 总被引:1,自引:0,他引:1
Szaluś-Jordanow O Kaba J Czopowicz M Witkowski L Nowicki M Nowicka D Stefańska I Rzewuska M Sobczak-Filipiak M Binek M Frymus T 《Polish journal of veterinary sciences》2010,13(3):437-445
Morel's disease caused by Staphylococcus aureus subsp. anaerobius was diagnosed for the first time in Poland in October 2006 in a goat flock. A second infected flock was found two months later. The course of the disease in both flocks was observed for 15-17 months. Clinical manifestation was confined to abscesses located near major superficial lymph nodes, mostly: superficial cervical, subiliac, parotid and mandibular. At necropsy no other lesions were found. The incubation period was estimated at 3 weeks. Clinical signs were seen both in young and adult goats and up to 7 abscesses in one animal were noted. Abscesses tended to persist for 1 to 5 months, then rupture and heal completely. The initial high in-flock point prevalence in both flocks (93.6% and 84.4%) dropped to approximately 10-30% during next 3-4 months. Until the end of the observation period the in-flock point prevalence remained at this level and only single abscesses were observed, mainly in young animals. No influence of the concurrent caprine arthritis encephalitis virus (CAEV) infection on the clinical course of Morel's disease was noticed. It is to be concluded that the clinical course of Morel's disease in a goat flock resembles caseous lymphadenitis (CLA). However, in Morel's disease abscesses occur more frequently in young goats and are located near, not inside, the lymph nodes, as in the case with CLA. Also, the incubation period of Morel's disease seems to be shorter (3 weeks versus 2-6 months in CLA). 相似文献