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In 2003 the Institute for Plant Protection in Agriculture and Forestry of the Republic of Croatia started a national survey of the possible occurrence of quarantine Thysanoptera species for the EU ( Scirtothrips spp., Thrips palmi Karny) in greenhouses in Croatia. The survey was continued yearly until 2006. This project involved the most important producers of vegetables and flowers in greenhouses and importers of pot plants and cut flowers. Eventual presence of especially T. palmi was checked in glasshouses and plastic greenhouses at 45 localities in 12 continental and 5 Mediterranean counties of Croatia. A total of 26 Thysanoptera species were recorded in the greenhouses, of which 14 species were collected from plant material, 13 were from blue sticky boards and 17 were from yellow sticky boards. Compared to the latest check list of Thysanoptera in Croatia, the following species were recorded for the first time for the country: Echinothrips americanus, Hercinothrips femoralis, Parthenothrips dracaenae and Thrips simplex . The survey did not establish the presence of EU quarantine Thysanoptera.

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Alpine grasslands harbour species-rich communities of plants and invertebrates. We examined how environmental variables and anthropogenic impact shape species richness and community structure of terrestrial gastropods in alpine grasslands in the Val Müstair (Eastern Alps, Switzerland). Gastropods were sampled using a standardised method at 76 sites spanning an elevation range from 1430 m to 2770 m. A total of 4763 specimens representing 52 species were recorded. Correspondence analysis based on presence/absence data revealed that the grassland gastropod community was structured in a complex way with elevation, wetness, grazing intensity and inclination of the sites as key factors, while abundance-based analysis identified the importance of the elevation and wetness of sites. Generalized linear model showed that species richness decreased with increasing elevation and increased with increasing soil pH. The grassland gastropod communities were characterized by a high beta diversity, as indicated by the SDR-simplex analysis. Species-specific traits of gastropods showed sensitivity to the environmental characters of the sites, as shown by a fourth-corner analysis.

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Abstract  

Consider a 3-dimensional point set

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which contains the incenters of all the nondegenerate tetrahedra with vertices from
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. In this paper we prove that then
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is dense in its convex hull. This settles the last unsolved variation in a sequence of similar questions initiated by D. Ismailescu, where he required to include other simplex centers, e.g. the orthocenters or the circumcenters. Our method allows us to generalize the planar incenter problem, showing that the denseness follows from a much weaker assumption for planar point sets.

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Abstract  

Thermodynamics and crystallization kinetics of the hydrothermal synthesis of Na4Ti4Si3O10 (NaTS) were systemically studied by both experiments and model simulation. Experimental results showed that the curve of crystallinity with time was a characteristic signmoid in the shape that indicated the crystallization of Na4Ti4Si3O10 was a typical spontaneous nucleation process on the laboratory scale. Crystallization of NaTS belongs to the liquid-liquid transformation mechanism and the reaction is endothermic (ΔH = 15.3 kJ/mol). A mathematic model of crystallization kinetics was developed to simulate the synthesis of NaTS. Runge-Kutta and simplex methods were adopted to solve the partial differential equations. Model results fitted well with the experimental data and showed that the synthesis process belongs to spontaneous nucleation and crystal growth. Moreover, the very small crystal growth constant (5.6·10−7) and gel dissolution constant (7.0·10−7) indicate they are the rate-limiting steps of the whole synthesis process.

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Acta Microbiologica et Immunologica Hungarica
Authors: M. Yazdanpanah, Mojgan Mokhtari, K. Mostofi, M. Soleimani, M. Ebrahimirad, H. Esmaili, and Sara Ahmadi

Oral poliovirus vaccine (OPV) is reported to be effective in treatment of recurrent herpes simplex (RHS). According to our observation during recent years, OPV was not only effective in management of RHS but also in some patients with concomitant recurrent aphthous stomatitis (RAS) reducing its severity and frequency. The purpose of this study was to evaluate the efficacy of OPV in the management of RAS.In a longitudinal, case — control study 48 patients with RAS were recruited. Twenty patients received OPV and 28 patients received placebo. OPV was administered in a dose of 4 drops at monthly intervals for 3 months to the study group while the control group received placebo. The results were registered in 3 months after the last dose.Eight cases (40%) in the OPV group showed significant reduction in the duration of the ulcers, while no change was seen in the control group (P = 0.048). The frequency of recurrence of RAS was reduced in 13 cases (65%) in the OPV group, and in 6 cases (21.4%) of the placebo group (P = 0.006). The severity of attacks was reduced in 12 cases (60%) in the OPV group and in 4 cases (14.3%) in the placebo group (P = 0.008).In conclusion OPV appeared to be effective in the management of RAS.

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Acta Alimentaria
Authors: L. Silva, G. Maia, P. Sousa, R. Figueiredo, M. Afonso, M. Gonzaga, C. Gomes, and E. Figueiredo

The purpose of this experiment was to evaluate the effect of heat treatment on the rheological properties of mixed nectars, based on cashew apple, mango, and acerola pulps. Ten different formulations with different mass fractions of cashew apple, mango, and acerola pulps were prepared using a simplex centroid design [with a total of 35% (w/w) pulp] and submitted to heat treatment at 90 °C for 1 min. Samples were collected before and after heat treatment and characterization of their rheological properties was carried out. The rheological behaviour was obtained at 25 °C, with shear rate ranging from 108 to 500 s−1 (upward curve) and from 500 to 108 s−1 (downward curve) for 1 min with 25 readings for each curve. The Ostwald de Waele model showed to be a good fit for all formulations studied, which showed a non-Newtonian behaviour and a pseudoplastic character. Results of apparent viscosity for the non-heated formulations were well fitted by the linear model and the heat treated formulations by the cubic model. The heat treated formulations had higher (P<0.05) values of consistency index and apparent viscosity, as well as lower (P<0.05) values of flow behaviour index compared to non-heated formulations. The rheological characterization of these formulations is a very useful tool during product development and processing control of mixed nectars of fruit juice.

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The objective of this study was to examine antibacterial, antifungal and antiviral properties of selected Phlomis species (Lamiaceae) growing in Turkey. The petroleum ether and methanol extracts of the seven species, namely P. armeniaca Willd., P. bourgaei Boiss., P. leucophracta P.H. Davis & Hub.-Mor., P. lunariifolia Sibth. & Sm., P. lycia D. Don, P. pungens Willd. var. pungens , and P. pungens var. hirta Velen. were tested against Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus, Bacillus subtilis , and Enterococcus faecalis for their antibacterial activity using ampicillin and oflaxocin as references. Antifungal activity of the same extracts was determined against Candida albicans using microdilution method with ketocanazole as reference. Both DNA virus Herpes simplex type-1 (HSV-1) and RNA virus Parainfluenza (PI-3) were employed for antiviral assessment of the Phlomis extracts using Madin-Darby Bovine Kidney and Vero cell lines in which acyclovir for HSV-1 and oseltamivir for PI-3 were employed as reference drugs. Although both the petroleum ether and methanol extracts seemed to exert similar antibacterial activity, the methanolic extracts were observed to be more active against S. aureus and E. faecalis . On the other hand, methanolic extract of P. pungens var. pungens possessed notable antiviral activity against both type of viruses.

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Antagonistic microorganisms have been used as biological control agents to reduce the use of chemical fungicides in the control of crop diseases. The present work was conducted to determine the antagonistic potential of Bacillus sp. isolates against the soil-borne fungus Cochliobolus sativus, the causal agent of barley common root (CRR) disease. Out of 525 isolates, 40 were showed in vitro antagonistic activity against the virulent C. sativus isolate CRR16. On the basis of 16S rRNA gene sequencing Bacillus sp. isolates are identified as B. atrophaeus, B. subtilis, Paenibacillus polymyxa, B. amyloliquefaciens, B. simplex and B. tequilensis. Results showed that Bacillus sp. had significant (P<0.05) antagonistic activities against the C. sativus where the percentage of radial growth inhibition of the fungi colonies ranged from 59 to 92%, compared to the untreated control. The B. subtilis isolate SY41B had the highest inhibition effect on the vegetative growth zones as compared with the other species isolates. In view of these, our results indicate that the antagonistic effect of the Bacillus sp. isolates may be important contributors as a biocontrol approach that could be employed as a part of integrated CRR management system.

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Acta Veterinaria Hungarica
Authors: Adauto Chiamenti, Cristiano Filho, Marcelo Moura, Fabíola Paula-Lopes, Jairo Neves, Cícero Neto, Paulo Gonçalves, Paulo Lima, and Marcos Oliveira

Experiments were carried out to investigate the beneficial effects of retinyl acetate (RAc) and retinoic acid (RA) on goat oocyte maturation as well as the effects of insulin-like growth factor-I (IGF-I), RAc and RA during embryo culture under chemically defined conditions. In Experiment 1, in vitro maturation (IVM) was performed in a chemically defined basic maturation medium (bMM) supplemented with 0.3 μM RAc or 0.5 μM RA. Presumptive zygotes and embryos (2–4 cells) were cultured in droplets of potassium simplex optimised medium (KSOM); however, none of the embryos reached the blastocyst stage. In Experiment 2, oocytes were matured in bMM + RAc or bMM + RA. Presumptive zygotes and 2- to 4-cell embryos were placed in fresh KSOM droplets supplemented with RAc, RA, IGF-I, RAc+IGF-I or RA+IGF-I. In Experiment 1, addition of RAc and RA to bMM increased (P < 0.05) the proportion of 2- to 4-cell embryos reaching the morula stage as compared to the control. In Experiment 2, supplementation of embryo culture media with retinoids and IGF-I increased (P < 0.05) the proportion of 2- to 4-cell stage embryos developing to the morula and blastocyst stage. Our data demonstrate that goat embryo production in chemically defined media could be improved by exogenous RAc or RA and by the interaction between retinoids and IGF-I, and that goat embryos can be produced in vitro from oocytes following protocols similar to those currently used for cattle.

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Fawl, R. L., Gesser, R. M., Valyi-Nagi, T. and Fraser, N. W. (1996): Reactivation of herpes simplex virus from latently infected mice after administration of cadmium is mouse-strain-dependent. J. Gen. Virol. 77, 2781

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