Kierrätettyjen ja biopohjaisten muovien elinkaariarviointi ja tekninen toimivuus

Environmental impacts of products can be reduced, for example, by reducing materials or by selecting materials, whose production causes low environmental impacts. In this thesis is studied, whether it is possible to reduce environmental impacts of a plastic product by using recycled or bio-based plastics. In this case, the environmental impacts refer to the greenhouse gas emissions and primary energy demand. Essential recycling methods of plastics are presented. The definitions and manufacturing of bio-based plastics are also discussed. Environmental impacts of recycled and bio-based plastics are assessed with life cycle assessment (LCA) method. In addition to the LCA, material tests are used to evaluate suitability of the plastics to be used in base stations of mobile networks. Testing included 6 months outdoor exposure in Finland, Greece and Kenya and also a long-term accelerated aging test at 85 °C and 85 % relative humidity. Testing samples were made with an actual production mould. Studied materials were polycarbonate (PC), polycarbonate-polyethylene terephthalate (PC/PET) blend, bio-based polyamide (PA) 410 and bio-based glass fibre reinforced polytrimethylene terephthalate (PTT). Results of LCA show that recycling of plastics reduces significantly environmental impacts of material production. If the plastic cover of a base station contains 100 % recycled PC, emissions and primary energy demand of plastics production are reduced by 86 %. Substituting 30 % of virgin PC by recycled PC reduces the environmental impacts of plastic production by 23 %. The effect of bio-based material content on the environmental impacts is not as straightforward. Depending on the plastic grade, the environmental impacts of the production of bio-based plastics are higher or lower than those of virgin PC. Based on the material testing, the properties of recycled PC are comparable to those of virgin PC. The bio-based plastics also performed well in the testing, and based on these results they provide sufficient properties to the plastic cover.Tuotteiden ympäristövaikutuksia voidaan pienentää esimerkiksi vähentämällä materiaalien määrää tai valitsemalla materiaaleja, joiden valmistus tuottaa pienet ympäristövaikutukset. Tässä työssä tutkitaan, voidaanko kierrätysmuovien tai biopohjaisten muovien käytöllä vähentää muovituotteen ympäristövaikutuksia. Ympäristövaikutuksilla tarkoitetaan tässä tapauksessa kasvihuonekaasupäästöjä ja primäärienergian kulutusta. Työssä esitetään keskeisimmät muovin kierrätysmenetelmät sekä selvitetään, mitä muovien biopohjaisuus tarkoittaa ja miten biopohjaisia muoveja valmistetaan. Kierrätettyjen ja biopohjaisten muovien valmistuksen ympäristövaikutuksia selvitetään standardisoidulla elinkaariarviointi-menetelmällä. Elinkaariarvioinnin lisäksi muovien soveltuvuutta mobiiliverkkojen tukiasemien kuorimateriaaliksi arvioidaan testien avulla. Testiohjelmaan kuuluu esimerkiksi 6 kk:n ulkoilmatestaus Suomessa, Kreikassa ja Keniassa sekä pitkäkestoinen vanhennustesti 85 °C:n lämpötilassa ja 85 % suhteellisessa kosteudessa. Testejä varten tutkituista muoveista ruiskupuristettiin todellisen tukiaseman suojamuoveja. Tutkittavat muovit ovat polykarbonaatti (PC), polykarbonaatti-polyeteeni tereftalaatti seos (PC/PET), biopohjainen polyamidi (PA) 410 ja biopohjainen, lasikuidulla lujitettu polytrimeteeni tereftalaatti (PTT). Työssä todettiin, että muovien kierrätys vähentää selvästi muovinvalmistuksen kasvihuonekaasupäästöjä sekä energian kulutusta. Jos tukiaseman suojakuori tehdään kokonaan kierrätetystä polykarbonaatista, muovin valmistuksen päästöt ja energian kulutus vähenevät 86 %. Korvaamalla 30 % neitseellisestä materiaalista kierrätetyllä, muovin valmistuksen ympäristövaikutukset laskevat 23 %. Biopohjaisen materiaalin vaikutus ympäristövaikutuksiin ei ollut yhtä suoraviivainen. Riippuen muovilaadusta biopohjaisten muovien valmistus aiheuttaa suuremmat tai pienemmät ympäristövaikutukset kuin neitseellinen polykarbonaatti. Tehtyjen testien perusteella kierrätetty PC on ominaisuuksiltaan lähellä neitseellistä PC:tä. Myös biopohjaiset muovit suoriutuivat testeistä ilman suuria ongelmia ja tarjoavat suojakuorelle vaadittavia ominaisuuksia

Novel manufacturing of multi-material component by hybrid friction stir channeling

The hybrid friction stir channeling (HC) is a recent manufacturing technique, reinforcing the broad range of solutions provided by the technological domain of solid-state friction stir-based welding and processing. HC enables the simultaneous welding of multiple components and the sub-surface channeling within the desired region at the stir zone. HC provides new demanding solutions having free path sub-surface channeling and welding for multi-material components with optimized physical and chemical performances. In the present investigation, a multi-material system consisting of 8 mm thick Al-Mg alloy (AA5083) and 3 mm thick oxygen free copper (Cu-OF) was processed by HC. A specially designed tool consists of the probe’s body features that steer materials extraction and the probe’s tip features that generate materials mixing was applied to produce sub-surface channel at AA5083, along with its simultaneous welding to Cu-OF material. Visual examination of the AA5083′s surface processed by the shoulder, cross-sectional dimensioning, optical 3D scanning of the internal surfaces of the channel, optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, electron backscatter diffraction and micro-hardness measurements were applied to investigate the results. The successful application of HC to manufacture multi-material Al-Cu component is demonstrated. A large sub-surface quasi rectangular channel with 9.6 mm in width per 3.3 mm in height was produced in the AA5083 rib along with defect free welding to thin Cu-OF plate at just below the channel region multi-material. The resulted sub-surface channel was consisted of unique wall surface features, with non-uniform and non-oriented surface roughness, suitable to activate turbulent fluid flow. The microhardness field depicts a higher-strength domain of the stirred material, at the ceiling of the sub-surface channel in comparison with the base materials. The welding zone comprises a metal matrix composite structure with Al-Cu inter-mixing and a mechanical hooking from Cu into the Al matrix. The metallurgical features of the weld stirred zone were analyzed, with an interpretation of Al-Cu phases, and solid solution of Al and Cu in each other. In this zone, Cu-rich lamellae regions are dispersed within the Al-matrix, presenting thin layers of discontinuous intermetallic compounds. The effective potential of manufacturing multi-material component for applicability in thermal management system is demonstrated

Thermal Control of Plasmonic Surface Lattice Resonances

Plasmonic metasurfaces exhibiting collective responses known as surface lattice resonances (SLRs) show potential for realizing tunable and flat photonic components for wavelength-selective processes, including lasing and optical nonlinearities. However, post-fabrication tuning of SLRs remains challenging, limiting the applicability of SLR-based components. Here, we demonstrate how the properties of high quality factor SLRs are easily modified by breaking the symmetry of the nanoparticle surroundings. We break the symmetry by changing the refractive index of the overlying immersion oil simply by controlling the ambient temperature of the device. We show that already modest temperature changes of 10{\deg}C can increase the quality factor of the investigated SLR from 400 to 750. Our results demonstrate accurate and reversible modification of the properties of the SLRs, paving the way towards tunable SLR-based photonic devices. On a more general level, our results demonstrate how symmetry breaking of the surrounding dielectric environment can be utilized for efficient and potentially ultrafast modification of the SLR properties

Branched-Chain Amino Acid Deprivation Decreases Lipid Oxidation and Lipogenesis in C2C12 Myotubes

Impaired lipid metabolism is a common risk factor underlying several metabolic diseases such as metabolic syndrome and type 2 diabetes. Branched-chain amino acids (BCAAs) that include valine, leucine and isoleucine have been proven to share a role in lipid metabolism and hence in maintaining metabolic health. We have previously introduced a hypothesis suggesting that BCAA degradation mechanistically connects to lipid oxidation and storage in skeletal muscle. To test our hypothesis, the present study examined the effects of BCAA deprivation and supplementation on lipid oxidation, lipogenesis and lipid droplet characteristics in murine C2C12 myotubes. In addition, the role of myotube contractions on cell metabolism was studied by utilizing in vitro skeletal-muscle-specific exercise-like electrical pulse stimulation (EPS). Our results showed that the deprivation of BCAAs decreased both lipid oxidation and lipogenesis in C2C12 myotubes. BCAA deprivation further diminished the number of lipid droplets in the EPS-treated myotubes. EPS decreased lipid oxidation especially when combined with high BCAA supplementation. Similar to BCAA deprivation, high BCAA supplementation also decreased lipid oxidation. The present results highlight the role of an adequate level of BCAAs in healthy lipid metabolism.Peer reviewe

PO-201 Aging attenuates the effect of aerobic capacity in muscle and serum metabolic profile but not in white adipose tissue

Objective Aerobic capacity is a quantitative predictor of the morbidity and mortality in many diverse patient populations. While aging is the main factor affecting aerobic capacity. The present study aimed to assess the effect of aerobic capacity and aging on metabolic profile in rats and to investigate the metabolic interactions between white adipose tissue (WAT), muscle and serum. Methods In this study, we used rat models that were selectively bred to differ in maximal running capacity (High capacity runners (HCR) and Low capacity runners (LCR)). Part of the rats were sacrificed after 9 months and the rest at 21 months. The effect of aerobic capacity on metabolic profile was assessed from 9 months old young rats (HCR-Y and LCR-Y), while the effect of aging on the metabolic profile in different capacity rats was determined comparing 9 months to 21 months old rats (HCR-O and LCR-O). Nuclear magnetic resonance (NMR) spectroscopy was performed to detect the metabolomics of WAT, muscle and serum. Partial least-squares-discriminant analysis (PLS-DA) was used for pattern recognition between HCR-Y and LCR-Y and between HCR-O and LCR-O. Metabolites with variable influence on projection (VIP) >1.0 and p<0.05 were classified as significantly different metabolites between groups. Spearman correlation was used to assess the metabolic interactions between white adipose tissue (WAT), muscle and serum. Results  HCR-Y rats had significantly higher skeletal muscle mass-to-body mass ratio (p<0.001), while lower body mass (p<0.001), fat mass (p<0.001), skeletal muscle mass (p=0.035) and fat mass to body mass ratio (p=0.004) than LCR-Y rats. The running capacity of HCR-Y rats was 132.7% (best running speed) better than LCR-Y rats (p<0.001). However, with age, the difference between body compositions between the two capacity groups became insignificant. HCR-O only had significantly lower body mass than the LCR-O (p=0.02). Running capacity (p=0.06) was 86.4% (best running speed) higher in the HCR-O rats than that of the LCR-O rats. PLS-DA revealed marked effects of aerobic capacity on metabolic profile in all three tissue types between HCR-Y and LCR-Y. The metabolic profile classification and prediction was best (i.e. sharper) in muscle than in WAT and serum. In addition, muscle and serum contained more significantly different metabolites than WAT in HCR-Y than in LCR-Y. Pathway analysis of the significantly different metabolites between HCR-Y and LCR-Y revealed that all the pathways belong to the lipid metabolism and amino acid metabolism in muscle while in serum it is only amino acid metabolism. However, in the case of the old groups, the PLS-DA gave reversed results. It revealed that WAT performed best in terms of classification and prediction of metabolites between HCR-O and LCR-O and had the most significantly different metabolites out of the three tissue types. The significantly different metabolites’ pathways belong to lipid metabolism in WAT. When assessing the metabolic interaction between different tissue types, all significantly different metabolites between HCR and LCR rats in young and old groups were moderately or strongly correlated (Spearman correlation between 0.45-0.9) with one or more metabolites in any of the three tissues. Conclusions In this study, we assessed the metabolic profile and body composition of WAT, muscle and serum in young and old rats with different aerobic capacities. We found that aerobic capacity greatly impacts body composition and the metabolic profile in muscle and serum in young rats, however the impact is attenuated with age. In addition, it is aging and not aerobic capacity that had the most influence on WAT metabolites. This suggest that WAT has more important role in aging process than previously assumed

Interactive effects of aging and aerobic capacity on energy metabolism-related metabolites of serum, skeletal muscle, and white adipose tissue

Aerobic capacity is a strong predictor of longevity. With aging, aerobic capacity decreases concomitantly with changes in whole body metabolism leading to increased disease risk. To address the role of aerobic capacity, aging, and their interaction on metabolism, we utilized rat models selectively bred for low and high intrinsic aerobic capacity (LCRs/HCRs) and compared the metabolomics of serum, muscle, and white adipose tissue (WAT) at two time points: Young rats were sacrificed at 9 months of age, and old rats were sacrificed at 21 months of age. Targeted and semi-quantitative metabolomics analysis was performed on the ultra-pressure liquid chromatography tandem mass spectrometry (UPLC-MS) platform. The effects of aerobic capacity, aging, and their interaction were studied via regression analysis. Our results showed that high aerobic capacity is associated with an accumulation of isovalerylcarnitine in muscle and serum at rest, which is likely due to more efficient leucine catabolism in muscle. With aging, several amino acids were downregulated in muscle, indicating more efficient amino acid metabolism, whereas in WAT less efficient amino acid metabolism and decreased mitochondrial beta-oxidation were observed. Our results further revealed that high aerobic capacity and aging interactively affect lipid metabolism in muscle and WAT, possibly combating unfavorable aging-related changes in whole body metabolism. Our results highlight the significant role of WAT metabolism for healthy aging.Peer reviewe

Physical activity in adulthood : genes and mortality

Observational studies report a strong inverse relationship between leisure-time physical activity and all-cause mortality. Despite suggestive evidence from population-based associations, scientists have not been able to show a beneficial effect of physical activity on the risk of death in controlled intervention studies among individuals who have been healthy at baseline. On the other hand, high cardiorespiratory fitness is known to be a strong predictor of reduced mortality, even more robust than physical activity level itself. Here, in both animals and/or human twins, we show that the same genetic factors influence physical activity levels, cardiorespiratory fitness, and risk of death. Previous observational follow-up studies in humans suggest that increasing fitness through physical activity levels could prolong life; however, our controlled interventional study with laboratory rats bred for low and high intrinsic fitness contrast with these findings. Also, we find no evidence for the suggested association using pairwise analysis among monozygotic twin pairs who are discordant in their physical activity levels. Based on both our animal and human findings, we propose that genetic pleiotropy might partly explain the frequently observed associations between high baseline physical activity and later reduced mortality in humans.Peer reviewe

Physical activity in adulthood: genes and mortality OPEN

Observational studies report a strong inverse relationship between leisure-time physical activity and allcause mortality. Despite suggestive evidence from population-based associations, scientists have not been able to show a beneficial effect of physical activity on the risk of death in controlled intervention studies among individuals who have been healthy at baseline. On the other hand, high cardiorespiratory fitness is known to be a strong predictor of reduced mortality, even more robust than physical activity level itself. Here, in both animals and/or human twins, we show that the same genetic factors influence physical activity levels, cardiorespiratory fitness, and risk of death. Previous observational follow-up studies in humans suggest that increasing fitness through physical activity levels could prolong life; however, our controlled interventional study with laboratory rats bred for low and high intrinsic fitness contrast with these findings. Also, we find no evidence for the suggested association using pairwise analysis among monozygotic twin pairs who are discordant in their physical activity levels. Based on both our animal and human findings, we propose that genetic pleiotropy might partly explain the frequently observed associations between high baseline physical activity and later reduced mortality in humans. Intervention studies in humans show several positive effects of exercise on physical performance and health-related metabolism 1 . Also, in humans, observational follow-up studies report an association between high baseline levels of leisure-time physical activity and low all-cause mortality 2 . However, a causal relationship between adulthood physical activity and mortality/lifespan has not been confirmed, either in randomized controlled intervention studies, with initially healthy individuals, or in animal experiment

Modelling aerosol transport and virus exposure with numerical simulations in relation to SARS-CoV-2 transmission by inhalation indoors

We provide research findings on the physics of aerosol and droplet dispersion relevant to the hypothesized aerosol transmission of SARS-CoV-2 during the current pandemic. We utilize physics-based modeling at different levels of complexity, along with previous literature on coronaviruses, to investigate the possibility of airborne transmission. The previous literature, our 0D-3D simulations by various physics-based models, and theoretical calculations, indicate that the typical size range of speech and cough originated droplets (dPeer reviewe

Meriseurannan tiekartta – SYKEn ylläpitämien ja koordinoimien meren tilaseurantojen nykytila ja kehittäminen

Raportissa kuvataan nykyiset SYKEn ylläpitämät ja koordinoimat meren kuormitus- ja tilaseurannat ja esitetään tavoitteita seurantojen kehittämiselle ja seurantatiedon käytön tehostamiselle vuoteen 2026 mennessä. Työ perustuu vuonna 2016 tehtyyn meriseurantojen toteutusta ja niiden kehittämistarvetta koskeneeseen kyselyyn, joka lähetettiin n. 30 seurantojen ja kehittämishankkeiden vastuuhenkilölle SYKEssä. Vastausten perusteella koottiin tiekartan alustava luonnos, jota on vuosina 2018-2019 päivitetty ja tarkistettu yhteistyössä seurantojen ja kehittämishankkeiden vastuuhenkilöiden kanssa. Nyt raportoitava versio antaa ajantasaisen kuvan SYKEn ylläpitämistä ja koordinoimista meren tilaseurannoista ja niiden kehittämisestä heinäkuussa 2020 alkaneen merenhoidon toisen seurantakauden kynnyksellä. Työ jakautuu aihealueisiin, joita ovat manuaaliseen näytteenottoon perustuva seuranta, automaatio, kaukokartoitus, kansalaishavainnointi, seurannan tietojärjestelmät, mallinnus ja sen tietotarpeet, seurantojen optimointi ja aineistojen yhteiskäyttö sekä merenhoidon ja HELCOM -työn tietotarpeet. Lisäksi tarkastellaan seuranta-aineistojen käyttöä. Seurantojen kehittämiselle esitetään välittömät tavoitteet (vastikään valmistunut tai valmistumassa oleva kehittämistyö) sekä tavoitteet vuoden 2020 aikana ja vuoteen 2026 mennessä