AN EFFECT OF CROSSING WITH FRENCH BEEF BREEDS ON MEAT PERFORMANCE OF BULLS

Pokus tova obuhvaćao je 13 čistokrvnih čeških bikova Pied (C), 10 Blon\u27d Aquitaine (B) i 11 Charolais (CH) generacije križanih bikova F₁, čije su majke češke Pied ženke. Za vrijeme tova životinje su hranjene kukuruznom silažom, sijenom lucerne i koncentratima do konačne težine od 567 (C), 573 (B) i 566 (CH) kg (starosti 550, 523 odn. 556 dana). Sto se tiče performance tovljenja prosječni dnevni prirast za vrijeme tova bio je za C, B i CH 1145, 1234 odn. 1332 g, prirast neto težine bio je 538, 607 odnosno 643 g. Značajno najveći postotak randmana (p<0.01) postigli su bikovi B (60.6%) u usporedbi s C (57.4%) i CH( 58.0%). Razlike u ukupnoj količini masti nisu bile značajne s relativnim vrijednostima 2.6 (C), 2.2 (B) i 2.7 (CH)%. Tehnološka analiza polovica otkrila je značajne razlike (p<0.01) u odnosu na prvorazredno meso (C=38.7%, B=41.3% i CH=40.1%). Značajno niži (p<0.05) omjer kostiju (16.7%) bio je karakterističan za slabije kosture skupine B u usporedbi sa skupinama C i CH (17.8%). Postojale su neznačajne razlike među skupinama u rezultatima kemijske analize uzoraka MLD (sadržaj suhe tvari, sadržaj masnoće i sadržaj sirovih bjelančevina).Fattening experiment involved 13 purebred Czech Pied (C) bulls, 10 Blond\u27d\u27Aquitaine (B) and 11 Charolais (CH) F₁ generation crossbred bulls coming from Czech Pied dams. During the fattening period, animals were fed with corn silage, alfalfa hay and concentrates up to the final weight of 567 (C), 573 (B) a 566 (CH) kg (age 550, 523 and 556 days resp). As for the fattening performance, average daily gain during the fattening period for C, B and CH was 1145, 1284 and 1332 g resp., net weight gain was 538,607, and 543 g resp. Significantly highest dressing percentage (p<0.01) reached B bulls (60.6%) compared with C (57.4%) and CH (58.0%). Differences in the total amount of fat were not significant with relative values 2.6 (c). 2.2 (b) and 2.7 (CH)%. The technological analysis of carcasses revealed significant differences (P<0.01) in the proportion of first-rate meat (C=38.7%, B=41.3% and CH=40.1%). More subtle skeletons of B group were characterised by significantly (P<0.05) lower proportion of bones (16.7%) in comparison with C and CH groups (17.8%). There were insignificant differences among groups in the results of chemical analysis of eye-muscle samples (dry matter content, fat content and crude protein content)

Graphene-Based Photodynamic Therapy and Overcoming Cancer Resistance Mechanisms: A Comprehensive Review

Hanna Dilenko, Kate&rcaron;ina Barto&ncaron; Tománková, Lucie Válková, Barbora Hošíková, Markéta Kola&rcaron;íková, Lukáš Malina, Robert Bajgar, Hana Kolá&rcaron;ov&#x00E1Department of Biophysics, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech RepublicCorrespondence: Kate&rcaron;ina Barto&ncaron; Tománková, Department of Biophysics, Faculty of Medicine and Dentistry, Palacky University, Hn&ecaron;votinska 3, Olomouc, 77900, Czech Republic, Tel +420 733 690 914, Email [email protected]: Photodynamic therapy (PDT) is a non-invasive therapy that has made significant progress in treating different diseases, including cancer, by utilizing new nanotechnology products such as graphene and its derivatives. Graphene-based materials have large surface area and photothermal effects thereby making them suitable candidates for PDT or photo-active drug carriers. The remarkable photophysical properties of graphene derivates facilitate the efficient generation of reactive oxygen species (ROS) upon light irradiation, which destroys cancer cells. Surface functionalization of graphene and its materials can also enhance their biocompatibility and anticancer activity. The paper delves into the distinct roles played by graphene-based materials in PDT such as photosensitizers (PS) and drug carriers while at the same time considers how these materials could be used to circumvent cancer resistance. This will provide readers with an extensive discussion of various pathways contributing to PDT inefficiency. Consequently, this comprehensive review underscores the vital roles that graphene and its derivatives may play in emerging PDT strategies for cancer treatment and other medical purposes. With a better comprehension of the current state of research and the existing challenges, the integration of graphene-based materials in PDT holds great promise for developing targeted, effective, and personalized cancer treatments.Keywords: graphene quantum dots, graphene oxide, cancer research, photosensitizers, drug deliver

Structural studies of thermally stable, combustion-resistant polymer composites

Composites of the industrially important polymer, poly(methyl methacrylate) (PMMA), were prepared by free-radical polymerization of MMA with varying amounts (1–30 wt. %) of sodium dioctylsulfosuccinate (Aerosol OT or AOT) surfactant added to the reaction mixture. The composites with AOT incorporated show enhanced resistance to thermal degradation compared to pure PMMA homopolymer, and micro-cone combustion calorimetry measurements also show that the composites are combustion-resistant. The physical properties of the polymers, particularly at low concentrations of surfactant, are not significantly modified by the incorporation of AOT, whereas the degradation is modified considerably for even the smallest concentration of AOT (1 wt. %). Structural analyses over very different lengthscales were performed. X-ray scattering was used to determine nm-scale structure, and scanning electron microscopy was used to determine μm-scale structure. Two self-assembled species were observed: large phase-separated regions of AOT using electron microscopy and regions of hexagonally packed rods of AOT using X-ray scattering. Therefore, the combustion resistance is observed whenever AOT self-assembles. These results demonstrate a promising method of physically incorporating a small organic molecule to obtain a highly thermally stable and combustion-resistant material without significantly changing the properties of the polymer

Measurement of the Shear Bond Stability of Different Generation Dental Adhesives

The study was aimed at comparison of adhesion of 4th to 6th generation of dentin adhesives by measuring the shear bond strength according to method ISO/TR 11405:1994(E). The study compared the adhesion systems Prompt L-Pop (6th generation), Excite and Prime & Bond NT belonging to the 5th generation, All Bond 2 from the 4th generation of adhesive and Evicrol Dual Bond, which belongs to 2nd generation of adhesives served as a control material. The etching of dentin was performed by the recommended conditioner based of phosphoric acid with the exception of Prompt L-Pop, in the case of Excite the etching was also performed by "no name" etching gel of similar composition for the sake of comparison. The adhesives were combined with two types of filling materials, the micro-hybrid composite Charisma and the Dyract AP compomer. In the Dyract AP compomer the authors also tested a procedure without dentin etching. In each adhesive the shear strength was tested in the group of 8-14 intact grinding molar with the use of measuring preparation Bencor Multi-T. It has become obvious that Prompt L-Pop provides an easier and faster application, while the bonding stability (9.2-9.6) MPa to both tested filling materials was close to adhesions (7.3-8.8) MPa observed in previous 4th and 5th generations, respectively. On the hand the adhesion system Excite of the 5th generation displayed, in using the original conditioner, approximately two-fold higher MPa values (17.3-19.0). The conditioning of dentin by a no-name gel resulted in adhesions at the level of other types, though. A high level of adhesion of 15.4 MPa was found in a combination of Dyract AP - P&B. In view of lower number of samples the results should be verified in further investigation. As expected, the lowest values were reached with the Evicrol Dual Bond system, where the adhesion values (2.9-3.2) MPa do not warrant sufficient bond strength of the filling material and tooth tissues

Nanocrystalline Zn2TiO4 films for distributed Bragg's reflectors operating in near infrared region

International audienceWe present a generic sol-gel approach for the preparation of a distributed Bragg reflector (DBR) based on combining nanocrystalline Zn2TiO4 with amorphous SiO2 xerogel films. We determined the effects of the annealing temperatures on the structural and optical properties of nanocrystalline Zn2TiO4 films. The increasing size of nanocrystals and film's density caused a regular growth of the films' refractive indices at 632 nm from the value of 1.837–1.960. The acquired data were applied to design the DBR with tailored reflectance at 980 nm and the data predicted by the theoretical model were compared with experimental transmission and reflection spectra. Although the high optical losses caused by the Rayleigh scattering were observed at short wavelengths, the prepared films were fully transparent above 600 nm. The uniform dielectric structure reflecting over 97% of incident light at 980 nm was prepared from eight Bragg's pairs. The normalized spectral bandwidth was about 0.22. We proved the nanocrystalline films exhibiting scattering in UV-VIS spectral region can be used for the construction of the distributed Bragg's reflectors operating in near infrared region. The presented approach can be easily extended to other nanocrystalline films allowing the integration of nanocrystalline luminophores into advanced photonic structures

Diamond Coated LW-SAW Sensors-Study of Diamond Thickness Effect

This study focuses on the fabrication and characterization of Love wave surface acoustic wave (LW-SAW) sensors with a thin nano-crystalline diamond (NCD) coating with an integrated microfluidics system. The effect of diamond layer thickness on the acoustic wave phase velocity and the sensor’s sensitivity have been investigated experimentally and compared with theoretical simulations. The fabricated sensors have been tested with a several liquids using a home-made microfluidics system