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911.
The aim of this study was to assess the exposure to organic dust and (1 → 3)-β-D-glucans in the buildings where an intensive breeding of swine is going on and evaluation of the impact of the breeding technical conditions on the observed levels of bioaerosols. The study was carried out in 30 swine farms differentiated by the size of the herd and technical conditions of breeding. In 35 randomly selected buildings, air samples were collected by stationary measurements to determine the concentrations of organic dust and (1 → 3)-β-D-glucans in inhalable and respirable fractions. Furthermore, each of the investigated buildings was precisely characterized by means of a questionnaire for technical conditions and type of breeding. In each of the points, the microclimate parameters were measured, i.e., temperature, relative humidity, CO2 concentration and air velocity. The analyzed levels of organic dust and (1 → 3)-β-D-glucans were characterized by a wide range of concentrations. For inhalable fraction, they reached respectively: organic dust (0.43–11.8 mg/m3), (1 → 3)-β-D-glucans (14–3,594 ng/m3). For respirable fraction, the results were as follows: organic dust (0.01–4.69 mg/m3), (1 → 3)-β-D-glucans (1–703 ng/m3). The concentrations of (1 → 3)-β-D-glucans were positively correlated with organic dust (r = 0.68; p < 0.001). The most significant factor increasing the concentrations of organic dust and (1 → 3)-β-D-glucans was the use of bedding in the form of cut straw. Additionally, the levels of (1 → 3)-β-D-glucans were affected by manual forage feeding, mechanical manure disposal and the lack of the liquid manure container in breeding buildings. In view of the hazardous effects of biological agents on the health of swine-breeding workers, the swine management systems without beddings should be used, along with automated dosing techniques.  相似文献   
912.
Patchoulol was subjected to transformation by Absidia coerulea AM93 and Mucor hiemalis AM450 strains. Both micro-organisms, which displayed differing vulnerability to the fungistatic action of the patchoulol, were capable of selective hydroxylations of the substrate. The major constituents of the mixtures after transformation were (8S)-8-hydroxypatchoulol and (9R)-9-hydroxypatchoulol; the transformation carried out by M. hiemalis resulted in the additional formation of (3R)-3-hydroxypatchoulol. The mixture of (8S)-8-hydroxypatchoulol and (9R)-9-hydroxypatchoulol can be used in the synthesis of patchoulenol, a compound with an odour very similar to that of a valuable fragrance, norpatchoulenol.  相似文献   
913.

Comparative effect of meta-topolin and other cytokinins was assessed to develop an efficient and reliable regeneration protocol for Tecoma stans, using mature nodal explants. The morphogenic effect of benzyl adenine (BA), kinetin (Kin), meta- topolin (mT) and 2-iP (2-iso pentenyl adenine) at various concentrations (1.0–10 µM) was studied individually or in combination with auxins (IAA, IBA or NAA). Superior multiplication rates were achieved on MS medium supplemented with mT and NAA. Of the tested combinations, maximum shoot regeneration (95%), mean shoot number (19.6?±?0.60) and length (5.26?±?0.73 cm) was recorded on MS medium supplemented with 7.5 µM mT?+?0.5 µM NAA after 8 weeks of incubation. Among the different auxins employed for in vitro root induction, 92.5% microshoots rooted on MS medium enriched with 1.0 µM IBA with 10.8?±?0.20 mean root number and 5.62?±?0.17 cm length after 4 weeks of incubation. The acclimatized plants grew well in green house with 90% survival rate. The gas chromatography–mass spectrometry (GC–MS) analysis of ethanol leaf extract of in vitro-raised plants yielded a higher number of compounds than control plant. The assessment of genetic fidelity among regenerants, using ISSR markers did not reveal any somaclonal variation. Therefore, the protocol developed appears to be simple and reliable for mass production of clones with higher diversity of secondary metabolites.

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Photosensitized efficacy of tetrasulfonated phthalocyanines of zinc, aluminum and nickel (ZnPcS4, AlPcS4 and NiPcS4, respectively) as studied by gramicidin channel (gA) photoinactivation was compared with adsorption of the dyes on the surface of a bilayer lipid membrane as measured by the inner field compensation method. The adsorption of the negatively charged phthalocyanines on diphytanoylphosphatidylcholine (DPhPC) membranes led to formation of a negative boundary potential difference between the membrane/water interfaces. Good correlation was shown between the photodynamic activity and the membrane binding of the three metallophthalocyanines. ZnPcS4 appeared to be the most potent of these photosensitizers, while NiPcS4 was completely ineffective. All of these phthalocyanines displayed no binding and negligible gA photoinactivation with membranes formed of glycerol monooleate (GMO), whereas Rose Bengal exhibited significant binding and photodynamic efficacy with GMO membranes. Gramicidin photoinactivation in the presence of AlPcS4, being insensitive to the ionic strength of the bathing solution, was inhibited by fluoride and attenuated by phosphate ions. A blue shift of the fluorescence peak position of ZnPcS4 dissolved in ethanol was elicited by phosphate, similarly to fluoride, which was indicative of the coordination interaction of these ions with the central metal atom of the phthalocyanine macrocycle. This interaction was enhanced in the medium modeling the water-membrane interface. The results obtained imply that binding of tetrasulfonated metallophthalocyanines to phospholipid membranes is determined primarily by metal-phosphate coordination.  相似文献   
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919.
Identification of individuals at risk of bone fractures remains challenging despite recent advances in bone strength assessment. In particular, the future degradation of the microstructure and load adaptation has been disregarded. Bone remodeling simulations have so far been restricted to small-volume samples. Here, we present a large-scale framework for predicting microstructural adaptation in whole human vertebrae. The load-adaptive bone remodeling simulations include estimations of appropriate bone loading of three load cases as boundary conditions with microfinite element analysis. Homeostatic adaptation of whole human vertebrae over a simulated period of 10 years is achieved with changes in bone volume fraction (BV/TV) of less than 5 %. Evaluation on subvolumes shows that simplifying boundary conditions reduces the ability of the system to maintain trabecular structures when keeping remodeling parameters unchanged. By rotating the loading direction, adaptation toward new loading conditions could be induced. This framework shows the possibility of using large-scale bone remodeling simulations toward a more accurate prediction of microstructural changes in whole human bones.  相似文献   
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