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31.
Various pesticides have immuno-suppressive effects, and thus the organisms become responsive to viral, bacterial and parasitic diseases and neoplasm. The aim of the study was to observe the structure of the small intestine (height of enterocytes and crypts), mucosal lymphoid tissue (Payer's patches, lymphocytes in lamina propria) and a lymph node after administration of bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-yl-methylcarbamate) on days 3, 10, 20, 30 and 60 of the experiment. The height of the observed enterocytes showed an increasing tendency. On days 20, 30 and 60 we also observed an increase in diameter of crypts located in intestinal epithelium. The number of cells in lamina propria mucosae was significantly reduced on days 20 and 30 after administration of bendiocarb. Observations of the lymph node showed that on days 10 and 20 there was a significant increase in relative volume of medulla at the expense of the relative volume of the cortex and a decrease in the number of lymphocytes. However, we recorded an increase in diameter of lymphocytes. The intracellular parasite Toxoplasma gondii (T. gondii) belongs to the most common pathogenic parasites in the world and it can cause serious health complications in pregnant and immunodeficient individuals. DNA isolation, standard polymerase chain reaction (PCR) and visualization in a 2.5 % agarose gel, the presence of DNA T. gondii was detected in no examined rabbit brain samples. Using real time PCR T. gondii DNA was detected and quantified in the three rabbit brain samples (10 %).  相似文献   
32.
Hydrogen sulphide, ammonia, nitrogen dioxide, mercaptans and sulphur dioxide (H2S, NH3, NO2, R-SH, SO2) concentrations were measured at the location in the vicinity of the waste dump to determine the air pollution level of these pollutants prior to the operation of the Mobile Thermal Treatment Plant. Samples were collected over one year period. Seasonal differences, and the influence of meteorological parameters (temperature, relative humidity, pressure and wind direction) on the air pollution levels were studied. Results show relatively low concentrations of H2S, NO2, R-SH and SO2, while NH3 levels were higher compared to the guideline values. Good weather conditions (high air pressure and low relative humidity) are connected to long range transport of NO2, while higher temperatures result in elevated NH3 and R-SH concentrations. Because of the predominant northeast wind direction (the same as the waste dump direction), the contribution of air pollution from the direction of the waste dump at the measuring site is significant, but that does not necessarily mean that the pollutants originated from that source.  相似文献   
33.
In this work was described poly(d,l-lactide) microwave synthesis using tin(II) 2-ethylhexanoate initiated ring-opening polymerization. Polymerization was performed at 100 °C with monomer to initiator molar ratio ([M]/[I]) of 5,000 in 30 min. The achieved number average molar mass of obtained polymers (determined by gel permeation chromatography) was 102,320 g/mol, with the polydispersion index, Q, 2.80. Structural characterization was performed by FT-IR spectroscopy followed characteristic bands. For applicative purposes the obtained polymer was purified during the procedure of microsphere preparation. Biodegradable microspheres prepared from poly(d,l-lactide) have been widely studied in recent years and have become well established controlled drug delivery systems. In this work microspheres were loaded with allyl thiosulfinate (allicin) and its transforments products (ajoene and vinyldithiine), as pharmacological active substances. The morphology of the microspheres was analyzed using a scanning electron microscope. Allicin was synthesized by acid oxidation of allyl disufide and purification of obtained products by liquid–liquid extraction with diethyl ether. Obtained allicin, purity 73%, was transformed using microwave in acetone solution, at solvent boiling temperature, for 5 min. For the quality and quantity analysis of allicin and its transformation process was used LC/MS chromatography. (E)- and (Z)-ajoene were detected at retention time 3.1 and 3.3 min, respectively, whence 3-vynil-4H-1,2-dithiine and 2-vynil-4H-1,3-dithiine were detected at 4.3 and 4.8 min, respectively. Retention time of allicin was 2.93 min, according to liquid chromatography results. HPLC method was used for assessment of pharmaceutical substances (alicine and alicine transforments) releasing from microspheres at room temperature in solutions with different pH (pH = 3 and pH = 8) for 24 h.  相似文献   
34.
The largest areas of acid sulphate (AS) soils in Europe are located in Finland, where 67,000–130,000 ha of AS soils are in agricultural use. In addition to their acidifying effects on waters, AS soils might be a significant source of greenhouse gases. In this pilot research, carbon and nitrogen content and microbial activity were studied in an AS and a non-AS soil. Large carbon and nitrogen stocks (110 Mg Corg ha?1 and 15 Mg Ntot ha?1) as well as high substrate induced respiration (33 μg CO2–C g?1h?1) were found in the C horizons of the AS soil but not in the non-AS soil. High microbial activity in these horizons of the AS soil was further confirmed by the measurement of dehydrogenase activity, basal respiration, the numbers of culturable bacterial cells, and the ratio of culturable to total numbers of cells. Still, the denitrifying enzyme activity was very low in the anaerobic horizons of the AS soil, indicating the prevalence of microbes other than denitrifiers. We suspect that the microbial community originated with the genesis of AS soil and has been supported by the large stocks of accumulated carbon and mineral nitrogen in the C horizons. If these permanently water-saturated subsoils are exposed to oxygen and their microbial activity consequently increases, large carbon and nitrogen stocks are likely to be mobilised, resulting in increased emission of greenhouse gases. Additional studies of boreal AS soils are needed to assess their potential contribution to increases in greenhouse gas fluxes at the local, regional, and global scales.  相似文献   
35.
36.
Summary. The diterpene neocembrene A or (1E,5E,9E,12R)-1,5,9-trimethyl-12-(1-methylethenyl)-1,5,9-cyclotetradecatriene, known as the trail-following pheromone of the advanced Termitidae Nasutitermitinae Nasutitermes exitiosus and Trinervitermes bettonianus, has been identified after SPME-GC/MS as the major component of the trail-following pheromone of the Rhinotermitidae Prorhinotermitinae, Prorhinotermes canalifrons and P. simplex. In all the other Rhinotermitidae studied until now, the major component of their trail pheromones is dodecatrienol ((3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol). This biochemical data further add to the anatomical and molecular characteristics that give a special status to the taxon Prorhinotermes among Rhinotermitidae. In Prorhinotermes canalifrons and P. simplex, neocembrene A was the only secretory compound specific to the sternal gland surface that could be detected after SPME. It elicited orientation as well as recruitment behavioral effects. However, the comparison of the respective biological activities triggered by neocembrene A and by sternal gland secretion suggests that minor components of the latter are acting in synergy with neocembrene A.  相似文献   
37.
38.
Elie Gaget  Diego Pavón-Jordán  Alison Johnston  Aleksi Lehikoinen  Wesley M. Hochachka  Brett K. Sandercock  Alaaeldin Soultan  Hichem Azafzaf  Nadjiba Bendjedda  Taulant Bino  Luka Božič  Preben Clausen  Mohamed Dakki  Koen Devos  Cristi Domsa  Vitor Encarnação  Kiraz Erciyas-Yavuz  Sándor Faragó  Teresa Frost  Clemence Gaudard  Lívia Gosztonyi  Fredrik Haas  Menno Hornman  Tom Langendoen  Christina Ieronymidou  Vasiliy A. Kostyushin  Lesley J. Lewis  Svein-Håkon Lorentsen  Leho Luigujõe  Włodzimierz Meissner  Tibor Mikuska  Blas Molina  Zuzana Musilová  Viktor Natykanets  Jean-Yves Paquet  Nicky Petkov  Danae Portolou  Jozef Ridzoň  Samir Sayoud  Marko Šćiban  Laimonas Sniauksta  Antra Stīpniece  Nicolas Strebel  Norbert Teufelbauer  Goran Topić  Danka Uzunova  Andrej Vizi  Johannes Wahl  Marco Zenatello  Jon E. Brommer 《Conservation biology》2021,35(3):834-845
Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species. An evaluation of the relative importance of colonization-extirpation processes is important to inform conservation strategies that aim for both climate debt reduction and species conservation. We assessed the colonization-extirpation dynamics involved in community changes in response to climate inside and outside PAs. To do so, we used 25 years of occurrence data of nonbreeding waterbirds in the western Palearctic (97 species, 7071 sites, 39 countries, 1993–2017). We used a community temperature index (CTI) framework based on species thermal affinities to investigate species turnover induced by temperature increase. We determined whether thermal community adjustment was associated with colonization by warm-dwelling species or extirpation of cold-dwelling species by modeling change in standard deviation of the CTI (CTISD). Using linear mixed-effects models, we investigated whether communities in PAs had lower climatic debt and different patterns of community change than communities outside PAs. For CTI and CTISD combined, communities inside PAs had more species, higher colonization, lower extirpation, and lower climatic debt (16%) than communities outside PAs. Thus, our results suggest that PAs facilitate 2 independent processes that shape community dynamics and maintain biodiversity. The community adjustment was, however, not sufficiently fast to keep pace with the large temperature increases in the central and northeastern western Palearctic. Our results underline the potential of combining CTI and CTISD metrics to improve understanding of the colonization-extirpation patterns driven by climate warming.  相似文献   
39.
The efficiency of providing a waste management system in the coastal part of Croatia consisting of four Dalmatian counties has been modelled. Two multi-criteria decision-making (MCDM) methods, PROMETHEE and GAIA, were applied to assist with the systematic analysis and evaluation of the alternatives. The analysis covered two levels; first, the potential number of waste management centres resulting from possible inter-county cooperation; and second, the relative merits of siting of waste management centres in the coastal or hinterland zone was evaluated. The problem was analysed according to several criteria; and ecological, economic, social and functional criteria sets were identified as relevant to the decision-making process. The PROMETHEE and GAIA methods were shown to be efficient tools for analysing the problem considered. Such an approach provided new insights to waste management planning at the strategic level, and gave a reason for rethinking some of the existing strategic waste management documents in Croatia.  相似文献   
40.
Current flood risk strategies in Malawi are characterized by community-based flood risk management (CB-FRM), even though studies explicitly documenting evidence of successful CB-FRM remain limited. This paper investigates the realities and challenges of CB-FRM as seen through a lens of different stakeholders. In order to capture the experiences of CB-FRM, a predominantly qualitative research framework was developed. In 2016, 11 focus group discussions with stakeholder groups (local communities, local government and non-governmental organisations) were held. Additionally, informal discussions, field visits, a short survey and an extensive desk study were undertaken. The findings were analysed according to the major themes that emerged related to the realities and challenges of specific stakeholder groups. Although response and relief still remain prominent components of CB-FRM in Malawi, a number of mitigation and preparedness activities is observed. However, a lack of in-country resources, relief-oriented aid approaches and an ‘aid dependency’ syndrome represent obstacles. Different stakeholder groups share similar challenges in terms of financing, participation, decentralised governance and project management. Lack of project sustainability and localised ownership also emerged as major challenges. The identified challenges shed light on the frontiers and directions in which improvements are needed, thus offering a valuable contribution to the existing knowledgebase.  相似文献   
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