Avaliação de diferentes híbridos suínos submetidos à insensibilização elétrica e gasosa (CO2): parte 2 - mensurações objetivas de qualidade

Suínos provenientes de três linhagens genética (A, B e C) comercializados no Brasil, com peso vivo de 100 a 120 kg foram submetidos ao insensibilizador elétrico manual (Karl Schermer 220-230/250 volts, 45-60 Hz e 1,4-1,5A) e ao gasoso coletivo (Combi-Butina 90% CO2) no mesmo abatedouro. O sistema gasoso proporcionou aos híbridos valores (b*) superiores (p<0,001) quando comparados ao sistema elétrico, assim como diferenças nos valores médios de refletância luminosa interna (Hennessy-gp4) aos 45 min. pm e 24ª h pm (p<0,05). Quando submetidos ao sistema gasoso, diferenças entre os híbridos nos valores médios de luminosidade superficial (L) 24ª h pm (p<0,0001), pH 24ª h pm (SM) (p<0,0001), valores (b*) 24ª h pm (p<0,05), reflectância luminosa interna aos 45 min e 24ª h (LD) (p<0,001) foram observadas. Utilizando-se o sistema manual elétrico verificaram-se diferenças significativas nos valores médios de refletância luminosa interna (LD) aos 45 min. e 24ª h pm (p<0,001), assim como nos valores médios de pH 24ª h pm (SM) e (SC) (p<0,05). Entretanto as diferenças obtidas entre os sistemas de insensibilização e híbridos estudados não foram suficientes para proporcionar diferenças significativas nos valores de capacidade de retenção de água, perda por exsudação e "umidade exprimível".

Avaliação de diferentes híbridos suínos submetidos à insensibilização elétrica e gasosa (CO2). Parte 3: mensurações visuais de qualidade

Três linhagens genética suína A, B e C comercializadas no Brasil, foram submetidas ao insensibilizador elétrico manual (Karl Schermer 220-230/250 volts, 45-60 Hz e 1,4 - 1,5 A) e ao sistema gasoso coletivo (COMBI-BUTINA 90% CO2) . A insensibilização elétrica proporcionou níveis mais elevados de salpicamento nas regiões do coxão mole (0,477 e 0,26, p < 0,01), paleta/cranial (0,154 e 0,039, p < 0,05), paleta/central (0,261 e 0,052, p < 0,001), paleta/caudal (0,180 e 0,030, p < 0,01), lombo/central (0,185 e 0,065, p < 0,01), lombo/caudal (0,06 e 0,207, p < 0,01) e lombo/lateral externa (0,061 e 0,013, p < 0,05), assim como salpicamento mais difuso nas regiões do coxão-mole (0,461 e 0,279, p < 0,05), paleta/cranial (0,154 e 0,039, p < 0,01), paleta/central (0,231 e 0,039, p < 0,001) e paleta/caudal (0,185 e 0,026, p < 0,001). O sistema elétrico também proporcionou maiores índices de escoriações da pele nas regiões da paleta (1,098 e 0,795, p < 0,001), corpo (1,04 e 0,948, p < 0,05) e pernil (0,84 e 0,68, p < 0,001), assim como elevados índices de reflexo palpebral (11,57%) comparativamente ao gasoso (2,86%), de um total de 426 suínos. Pequenos índices de fraturas ósseas e contusões musculares em animais de ambos os sistemas foram observados.

Avaliação de diferentes híbridos suínos submetidos à insensibilização elétrica e gasosa (CO2). Parte 1: mensuração de indicadores sanguíneos de estresse

Suínos provenientes de três linhagens genéticas A, B e C comercializadas no Brasil, com peso vivo de 100 a 120 kg foram submetidos ao insensibilizador elétrico manual (Karl Schermer 220-230/250 volts, 45-60 Hz e 1,4 -1,5 A) e ao sistema gasoso coletivo (COMBI-BUTINA 90% CO2). Alíquotas sanguíneas, para determinação dos níveis de creatina fosfoquinase (CPK), lactato e cortisol, assim como amostras do músculo semimembranosus (10 g) para a determinação do gene halotano, foram coletadas. Comparando-se os sistemas de insensibilização elétrico e gasoso (CO2), o elétrico demonstrou ser mais estressante, proporcionando maiores concentrações plasmáticas de cortisol (p < 0,001) e lactato (p < 0,001) para as linhagens genéticas A e C, nas condições estudadas, porém não se observou diferenças significativas para os indicadores sanguíneos e sistemas de insensibilização em questão quando a linhagem B foi considerada. Diferenças significativas entre as linhagens genéticas A, B e C foram obtidas comparando-se os valores plasmáticos de creatina fosfoquinase (p < 0,001), lactato (p < 0,001) e cortisol (p < 0,001) quando atordoados com o sistema gasoso, entretanto, quando o sistema elétrico foi utilizado, somente os valores de cortisol apresentaram diferenças significativas (p < 0,001). A presença do gene halotano (Nn) foi observada somente na linhagem B.

Pre-treatment of thermoduric spores in CO2 modified atmosphere and their survivability during food extrusion

The aim of this experiment was to evaluate how susceptible spores become to mechanical damage during food extrusion after being submitted to CO2. B. stearothermophilus spores sowed to corn and soy mix were submitted to 99% CO2 for 10 days and extruded in a single-screw extruder. The treatments were: T1 - spore-containing samples, extruded at screw rotational speed of 65 rpm and barrel wall temperature of 80 °C; T2 - as T1, except for screw rotational speed of 150 rpm; and T3 - as T2, except that samples were submitted to the modified atmosphere. The results for cell viability, minimum and maximum residence times, and static pressure were T1 - 19.90 ± 3.24%, 123.3 ± 14.50 seconds; 203.3 ± 14.05 seconds; 2.217 ± 62 kPa; T2 - 21.42 ± 8.24%, 70.00 ± 5.77 seconds; 170.00 ± 4.67 seconds; 2.310 ± 107 kPa; and T3 - 11.06 ± 2.46%, 86.00 ± 7.23 seconds; 186.00 ± 7.50 seconds; 2.403 ± 93 kPa, respectively. It was concluded that the extrusion process did reduce the cell count. However, screw rotational speed variation or CO2 pre-treatment did not affect cell viability.

Immunomodulatory effects of supercritical fluid CO2 extracts from freeze-dried powder of Tenebrio molitor larvae (yellow mealworm)

Abstract In order to take full advantage of Tenebrio molitor larvae (yellow mealworm) resources, the supercritical CO2 fluid freeze-dried powder of T. molitor larvae (fdTML) extraction on the immune systems of mice was carried out. The results about the effects of supercritical CO2 fluid fdTML extraction on carbon expurgation and phagocytosis of peritoneal macrophages experiments of mice indicated that the fdTML extraction enhanced observably carbon expurgatory index, phagocytic rate and phagocytic index. The fdTML extraction could stimulate response of delayed hypersensitivity. The proliferation of ConA-induced mitogenic reponse for spleen lymphocyte was also increased. The amount of hemolytic antibody in mice serum increased compared with those of the control group mice. The half of hemolysis values in serum of treated mice increased compared to the control group. Furthermore, serum NO content in all treatment groups was higher than that of the control group whereas acid phosphatase and alkaline phosphatase activity was only significantly higher relative to the control group. Our findings suggest that supercritical CO2 fluid the fdTML extraction has potential as a health food supplement.

Inactivation of Staphylococcus aureus in raw salmon with supercritical CO2 using experimental design

Abstract Considering the microbial safety of consumption of raw foods (Asian food), this study aimed to explore the inactivation S. aureus in raw salmon by supercritical CO2 treatment (SC-CO2). For this purpose, experimental design methodology was employed as a tool to evaluate the effects of pressure (120-220 bar), the depressurization rate (10 to 100 bar.min–1) and the salmon:CO2 mass relation (1:0.2 to 1:1.0). It was observed that the pressure and the depressurization rate was statistically significant, i.e. the higher the system pressure and depressurization rate, the greater the microbial inactivation. The salmon: CO2 mass relation did not influence the S. aureus inactivation in raw salmon. There was a total reduction in S. aureus with 225 bar, a depressurizing rate of 100 bar.min–1, a salmon: CO2 mass relation of 1:0.6, for 2 hours at 33 °C.

Climate change and global responsibility - the role of energy consumption, GDP and CO2 emissions

Climate change is one of the biggest challenges faced by this generation. Despite being the single most important environmental challenge facing the planet and despite over two decades of international climate negotiations, global greenhouse gas (GHG) emissions continue to rise. By the middle of this century, GHGs must be reduced by as much as 40-70% if dangerous climate change is to be avoided. In the Kyoto Protocol no quantitative emission limitation and reduction commitments were placed on the developing countries. For the planning of the future commitments period and possible participation of developing countries, information of the functioning of the energy systems, CO2 emissions development in different sectors, energy use and technological development in developing countries is essential. In addition to the per capita emissions, the efficiency of the energy system in relation to GHG emissions is crucial for the decision of future long-term burden sharing between countries. Country’s future development of CO2 emissions can be defined by the estimated CO2 intensity of the future and the estimated GDP growth. The changes in CO2 intensity depend on several factors, but generally developed countries’ intensity has been increasing in the industrialization phase and decreasing when their economy shifts more towards the system dominated by the service sector. The level of the CO2 intensity depends by a large extent on the production structure and the energy sources that are used. Currently one of the most urgent issues regarding global climate change is to decide the future of the Kyoto Protocol. Negotiations on this topic have already been initiated, with the aim of being finalised by the 2015. This thesis provides insights into the various approaches that can be used to characterise the concept of comparable efforts for developing countries in a future international climate agreement. The thesis examines the post-Kyoto burden sharing questions for developing countries using the contraction and convergence model, which is one approach that has been proposed to allocate commitments regarding future GHG emissions mitigation. This new approach is a practical tool for the evaluation of the Kyoto climate policy process and global climate change negotiations from the perspective of the developing countries.

Production of magnesium carbonates from serpentinites for CO2 mineral sequestration : optimisation towards industrial application

Global warming is one of the most alarming problems of this century. Initial scepticism concerning its validity is currently dwarfed by the intensification of extreme weather events whilst the gradual arising level of anthropogenic CO2 is pointed out as its main driver. Most of the greenhouse gas (GHG) emissions come from large point sources (heat and power production and industrial processes) and the continued use of fossil fuels requires quick and effective measures to meet the world’s energy demand whilst (at least) stabilizing CO2 atmospheric levels. The framework known as Carbon Capture and Storage (CCS) – or Carbon Capture Utilization and Storage (CCUS) – comprises a portfolio of technologies applicable to large‐scale GHG sources for preventing CO2 from entering the atmosphere. Amongst them, CO2 capture and mineralisation (CCM) presents the highest potential for CO2 sequestration as the predicted carbon storage capacity (as mineral carbonates) far exceeds the estimated levels of the worldwide identified fossil fuel reserves. The work presented in this thesis aims at taking a step forward to the deployment of an energy/cost effective process for simultaneous capture and storage of CO2 in the form of thermodynamically stable and environmentally friendly solid carbonates. R&D work on the process considered here began in 2007 at Åbo Akademi University in Finland. It involves the processing of magnesium silicate minerals with recyclable ammonium salts for extraction of magnesium at ambient pressure and 400‐440⁰C, followed by aqueous precipitation of magnesium in the form of hydroxide, Mg(OH)2, and finally Mg(OH)2 carbonation in a pressurised fluidized bed reactor at ~510⁰C and ~20 bar PCO2 to produce high purity MgCO3. Rock material taken from the Hitura nickel mine, Finland, and serpentinite collected from Bragança, Portugal, were tested for magnesium extraction with both ammonium sulphate and bisulphate (AS and ABS) for determination of optimal operation parameters, primarily: reaction time, reactor type and presence of moisture. Typical efficiencies range from 50 to 80% of magnesium extraction at 350‐450⁰C. In general ABS performs better than AS showing comparable efficiencies at lower temperature and reaction times. The best experimental results so far obtained include 80% magnesium extraction with ABS at 450⁰C in a laboratory scale rotary kiln and 70% Mg(OH)2 carbonation in the PFB at 500⁰C, 20 bar CO2 pressure for 15 minutes. The extraction reaction with ammonium salts is not at all selective towards magnesium. Other elements like iron, nickel, chromium, copper, etc., are also co‐extracted. Their separation, recovery and valorisation are addressed as well and found to be of great importance. The assessment of the exergetic performance of the process was carried out using Aspen Plus® software and pinch analysis technology. The choice of fluxing agent and its recovery method have a decisive sway in the performance of the process: AS is recovered by crystallisation and in general the whole process requires more exergy (2.48–5.09 GJ/tCO2sequestered) than ABS (2.48–4.47 GJ/tCO2sequestered) when ABS is recovered by thermal decomposition. However, the corrosive nature of molten ABS and operational problems inherent to thermal regeneration of ABS prohibit this route. Regeneration of ABS through addition of H2SO4 to AS (followed by crystallisation) results in an overall negative exergy balance (mainly at the expense of low grade heat) but will flood the system with sulphates. Although the ÅA route is still energy intensive, its performance is comparable to conventional CO2 capture methods using alkanolamine solvents. An energy‐neutral process is dependent on the availability and quality of nearby waste heat and economic viability might be achieved with: magnesium extraction and carbonation levels ≥ 90%, the processing of CO2‐containing flue gases (eliminating the expensive capture step) and production of marketable products.

Characterization of amine-based CO2 adsorbent for Direct Air Capture

Direct air capture technologies extract CO2 from air at a concentration of as low as 400ppm. The captured CO2 can be used for the production of synthetic methane or liquid fuels. In the literature survey of this thesis, results related to direct air capture by using solid sorbents are presented and critically discussed. In the experimental part, a proprietary amine functionalized resin is characterized for direct air capture. Structural comparison is also made to a commercial resin of similar type. Based on the literature survey, the most important parameters in direct air capture process are low adsorption and desorption temperatures, good cyclic stability in dry and humid conditions, high CO2 outlet purity and a high working capacity. Primary amine functionalized solid sorbents are found to often have good qualities for direct air capture, but overall process performance is rarely studied exhaustively. Based on FTIR spectra, both resin adsorbents are found to be consisted of polystyrene functionalized with primary amine, and capture CO2 by forming carbamate. The commercial resin is more porous, has a slightly higher particle size and contains fewer impurities. Important physical parameters are gained of the proprietary resin, such as internal porosity and median particle size. The resin’s amine group is found to endure thermal treatment reasonably well. CO2 adsorption capacity gained by thermal gravimetry from 400ppm CO2 is highest at 25oC, and is found to be reasonable compared to values presented in literature. Thus, the resin is stated to exhibit promising qualities for direct air capture.

Desiccation tolerance and DNA integrity in Eugenia pleurantha O. Berg. (myrtaceae) seeds

The aim of this study was to assess the desiccation tolerance and DNA integrity in Eugenia pleurantha seeds dehydrated to different moisture contents (MCs). Seeds extracted from mature fruits were submmited to drying in silica gel and evaluated at every five percentual points of decrease from the initial MC (35.5%, fresh weight basis). The effects of dehydration on seeds were verified through germination tests and DNA integrity assessment. Undried seeds achieved 87% germination, value reduced to 36% after being dried to 9.8% MC. When dried slightly more, to 7.4% MC, seeds were no longer able to germinate, suggesting an intermediate behavior in relation to desiccation tolerance. It was observed DNA degradation in seeds with 7.4% MC, which might have contributed to the loss of seed germination.

Desiccation tolerance and dna integrity in Eugenia pleurantha o. berg. (Myrtaceae) seeds

The aim of this study was to assess the desiccation tolerance and DNA integrity in Eugenia pleurantha seeds dehydrated to different moisture contents (MCs). Seeds extracted from mature fruits were dried in silica gel and evaluated at every five percentual points of decrease from the initial MC (35.5%, fresh weight basis). The effects of dehydration on seeds were verified through germination tests and DNA integrity assessment. Undried seeds achieved 87% germination, value reduced to 36% after being dried to 9.8% MC. When dried slightly more, to 7.4% MC, seeds were no longer able to germinate, suggesting an intermediate behavior in relation to desiccation tolerance. DNA degradation was observed in seeds with 7.4% MC, which might have contributed to the loss of seed germination.

Changes in gene expression during drying and imbibition of desiccation sensitive Magnolia ovata (A. St.-Hil.) spreng. seeds

Seeds of Magnolia ovata were dried to different water contents to assess the viability and transcript abundance of genes related to seed development, cell cycle, cytoskeleton and desiccation tolerance.The expression of development, cell cycle and cytoskeleton relative genes (ABI3, CDC2-like and ACT2) alone could not explain the germination behaviour of M. ovata seeds in relation to drying damage. Irrespective of their initial water content, the seeds performed in the same way during the initial period of germination and the deleterious effects of desiccation only occurred in later stages. Expression of PKABA1, sHSP17.5 and 2-Cys-PRX did not show a relationship with desiccation. However, the expression patterns of PKABA1 and sHSP17.5 suggested the participation of these genes in protective mechanisms during the imbibition of M. ovata seeds.

Desiccation tolerance of Tapirira obtusa seeds collected from different environments

This study was aimed at evaluating the desiccation sensitivity in seeds of the tree Tapirira obtusa (Benth.) J. D. Mitchell collected from three different environments and subjected to two distinct drying speeds. Seeds were collected from a rocky area, in the "Cerrado", and in a riparian forest area, in the region of municipality of Lavras, State of Minas Gerais. The seeds were subjected to drying with magnesium chloride (slow drying) or silica gel (fast drying), into closed environment, until moisture contents of 40%, 30%, 20% and 10%, considering as control, the percentage of germination at the initial moisture content in each environment, which varied from 47% to 50%. Percentages of germination and normal seedlings as well as germination speed index were assessed. For the three environments studied, there was no effect of slow drying on seed germination. Seeds from area of Cerrado, however, have shown a slight reduction on germination when subjected to fast drying. Oppositely, seeds from rocky area had germination increased when subjected to fast drying. Seeds from riparian forest area had no reduction on germination percentage, independent of drying speed. Results suggest that seeds of T. obtusa are not sensitive to desiccation.