This study aimed to evaluate the nutritional behavior and some immunological criteria (encapsulation index and phenoloxidase – PO activity, the key enzyme for melanization) as well as to study the effect of protein to fat (P : F) diets on hypopharyngeal gland (HPG) protein content. Bees were restricted to consuming specific P : F diets varying in fat ratio under laboratory conditions. These diets included 25 : 1, 10 : 1, 5 : 1 (low-fat diet, LFD); 1 : 1 (equal-fat diet); 1 : 5, 1 : 10 (high-fat diet, HFD), and 1 : 0 (zero-fat diet) as a control. Bees preferred low-fat diets over high-fat diets, where it was 11.27 ± 0.68 μl · day–1 bee in 10 : 1 P : F, while it was 4.99 ± 0.67 μl · day–1 bee in 1 : 10 P : F. However, sucrose consumption was higher in high-fat diets where it was 25.83 ± 1.69 μl · day ^–1 bee in 10 : 1 P: F, while it was 30.66 ± 0.9 μl · day–1 bee in 1 : 10 P : F. The encapsulation index and phenoloxidase activity of bees were positively linked with the fat level they consumed during all 10 days. The maximum percentage of encapsulation index was 74.6 ± 7.2% in bees fed a high-fat diet, whereas the minimum percentage was 16.5 ± 3.6% in bees which consumed a lowfat diet. Similarly, phenoloxidase activity increased in the haemolymph with increasing fat consumed by bees (0.001 ± 0.0001 and 0.005 ± 0.0003 mM · min ^–1 · mg ^–1 at 25 : 1 and 1 : 10 P : F, respectively). The protein content of hypopharyngeal glands in bees which consumed HFD was double that of LFD. Overall results suggest a connection between a fat diet and bee health, indicating that colony losses in some cases can be reduced by providing a certain level of fat supplemental feeding along with sucrose and protein nutrition.

The formation of texture and microstructure in polycrystalline Cu and Cu-5 wt. % Al alloy during two modes of homogenous rolling have been compared. Two samples of each metal were rolled. One sample was rolled unidirectionally, while the other by reverse rolling. Some differences in the textures depending on the rolling mode have been observed in the range of deformation of the Cu-5 wt. % Al alloy where intensive twinning took place. It was also found that the texture of reverse rolling was more homogeneous across the thickness of the rolled alloy sheet than the texture of unidirectionally rolled material. No clear effect of the rolling mode on microstructure has been observed.

In order to improve the output performance of direct methanol fuel cell, the finite-time thermodynamic model of direct methanol fuel cell is developed in this paper. Then, mathematical expressions for energy efficiency, power density, exergy efficiency and exergy coefficient of performance are derived. In addition, the effects of operating temperature, inlet pres-sure and membrane thickness on the performance of direct methanol fuel cells are considered. The results show that the exergetic performance coefficient not only considers the exergy loss rate to minimize the loss, but also the power density of the direct methanol fuel cell to maximize its power density and improve its efficiency. Therefore, the exergetic perfor-mance coefficient is a better performance criterion than conventional power and efficiency. In addition, increasing the inlet pressure and decreasing the membrane thickness can significantly improve the exergetic performance coefficient and en-ergy efficiency.

The paper presents the results and analysis of biomass processing in order to provide the conditions for the most profitable use of the biomass in modern and efficient power generation systems with particular attention put on the decrease of the emission of carbon dioxide (CO2) and no need to develop carbon capture and storage plants. The promising concept of CO2 storage via the production of biochar and the advantages of its application as a promising carbon sink is also presented and the results are supported by authors’ own experimental data. The idea enables the production of electricity, as well as (optionally) heat and cold from the thermal treatment of biomass with simultaneous storage of the CO2 in a stable and environmentally-friendly way. The key part of the process is run in a specially-designed reactor where the biomass is heated up in the absence of oxygen. The evolved volatile matter is used to produce heat/cold and electricity while the remaining solid product (almost completely dry residue) is sequestrated in soil. The results indicate that in order to reduce the emission of CO2 the biomass should rather be ‘cut and char’ than just ‘cut and burn’, particularly that the charred biomass may also become a significant source of nutrients for the plants after sequestration in soil.

This paper presents the image of St. Joseph in one of the sermons preached by Joseph Ratzinger on the occasion of the 60th anniversary of religious vows by two sisters from the Congregation of Our Lady of Sorrows. The special character of this approach lies in the fact that the main source of inspiration for the Bavarian Theologian is a relief from the Baroque altar located in a specific and largely unknown church in Portugal. The preacher – thanks to the reading of certain elements contained in the sculpture of St. Joseph – was able to emphasize aspects that had so far remained invisible: a readiness to do God’s will, going on a pilgrimage in faith or resignation from one’s own plans made to the point of heroism. Ratzinger’s interpretation, reinforced with references to Sacred Scripture, confirms the value of the presence of a work of art among theological topics.