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  • Liiwand, Maj Britt (2022)
    Chronic stress has been linked to the pathogenesis of various disorders, such as generalized anxiety disorder, depression, and post-traumatic stress disorder (PTSD). Stress-induced hyperexcitability of the basolateral amygdala (BLA) has implications in anxiety-like behavior. Promising evidence points to the direction of GluK1 subunit containing kainate receptors (KARs) having a role in the modulation of GABAergic transmission in the lateral amygdala (LA). The aim of the present study was to investigate whether dysfunction of KARs contribute to stress-induced amygdala hyperexcitability and anxiogenesis in mice. Chronic restraint stress (CRS) is an animal model simulating chronic psychological stress. An in situ hybridization experiment was performed to investigate how CRS affects expression levels of GluK1 in the different neuronal populations in the LA. These data show that CRS leads to downregulation of GluK1 expression in the parvalbumin-positive (PV+) interneurons specifically. Patch clamp recordings of spontaneous inhibitory postsynaptic currents showed that CRS did not affect synaptic GABAergic transmission to the principal neurons in the LA. Lastly, conditional knock-out (cKO) mice that have the Grik1 gene knocked out selectively in the PV-expressing interneurons showed no change in anxiety-like behavior after CRS while their wild-type counterparts demonstrated an increase in anxiety-like behavior observable in the elevated plus maze test. Thus, ablation of GluK1 in PV+ interneurons affects the stress-induced anxiogenesis. Due to low number of animals, it cannot be confirmed yet whether the deletion leads to stress resilience or a phenotype where even regular handling is an aversive experience comparable to physical restraint. GluK1 KAR modulation of PV+ interneuron excitability and its susceptibility to stress-related alterations is only a recently discovered phenomenon, and even though this study provides some insight into the underlying mechanism, further research is needed. Systematic characterization of the mechanism could provide a novel tool for understanding and treating stress-related pathological anxiety, possibly helping patients suffering from anxiety disorders resistant to current treatments available.
  • Lindberg, Maiju (2023)
    As the most common mental disorder, anxiety disorders present a major burden to healthcare worldwide and a challenging problem to overcome for the ones suffering from it. Recently, researchers have started to recognize that the relationship between sleep and anxiety disorders is bidirectional; disturbed sleep is a potential risk factor for the progression of anxiety and anxiety can lead to sleep disturbances. However, the neural mechanisms underlying anxiety and sleep problems are still poorly recognized. In this study, we used a chronic sleep fragmentation (SF) paradigm to investigate how disturbed sleep alters anxiety-like behavior in mice and what are the potential underlying neuronal mechanisms. This model was chosen because we wanted to focus on a common form of disturbed sleep in humans rather than total sleep deprivation. We measured anxiety-like behavior in the light-dark box and open field tests right after the 2-week SF period and again after a week of recovery. Additionally, we performed immunohistochemical analysis to study prolonged cell activity (transcription factor ∆FosB), parvalbumin (PV) interneurons and perineuronal net (PNN) structures in the medial prefrontal cortex (mPFC) of the mice. Changes in mPFC activity and related brain areas are associated to anxiety in humans and anxiety-like behavior in rodents alike. Similarly, changes in PV interneurons and PNNs, that regulates PV cell function, are associated to anxiety-like behavior. However, PV interneurons and PNNs have not been previously studied in a setting that combines sleep fragmentation and anxiety-like behavior. We found that chronic SF increases anxiety-like behavior in female mice and that this effect persists at least for a week. Conversely, we did not observe significant increase in anxiety-like behavior in male mice. Both female and male mice showed decrease in ∆FosB in the mPFC suggesting that SF treated mice had lower overall levels of cell activity. Similarly, we found that SF treated mice had decreased PV interneuron intensity in both sexes which could indicate changes in the cell activity. However, the pattern of changes in the IHC results was not identical in males and females. Based on the IHC results, we suggest that SF affects neuronal processes in both sexes but the disparity in them could explain the difference in the behavioral effect. This thesis shows that disturbed sleep can lead to increased anxiety-like behavior in rodent models and recognizes potential targets to study the mechanisms behind the phenomena.
  • Heikkinen, Panu (2021)
    This thesis is a case study that examines the reasons for the lack of citizen participation in the planning process of Kalasataman keskus, and, more generally, in the planning of megaprojects. The main observation of this thesis is that there are several reasons for this. Based on the interviews of main characters taking part in the planning of Kalasataman keskus and the planning documents of Kalasataman keskus (as well as the previous research on the topic) the reasons for lack of citizen participation were: the location of planning area with few inhabitants, the large size of the planning project, technical difficulty of the planning project, the weight on the commercial aspects of the planning, and the view of the planners (relying on experts in the planning). When these results were viewed together with the previous research, it was noted that, as the previous research suggests, the traditional practices of urban planning hinder citizen participation in planning. (For example, seeing that urban planning relies on the technical knowledge of experts.) Moreover, based on the findings of the thesis as well as the previous research, it is possible to see that when the tradition, which emphasizes expert knowledge, is paired with a planning project where the city has a commercial partner, the structures and procedures of planning tend to exclude citizens’ views from the planning process. Partly based on such findings, the thesis suggests that, if the intention is to strengthen citizen participation in, especially large, planning projects, the city should aim to strengthen, for example, local community organizations.
  • Råberg, Mirka (2022)
    Circular economy (CE) is often offered as a solution to mitigate climate change and more efficient resource use. However, the socio-cultural side of transformation to CE is widely overlooked in the academic literature (Kirchherr et al., 2018) and in the context of CE, consumer-citizens are often framed as “consumers”, “users” and in terms of “acceptance” of new products and modes of provision (Hobson & Lynch, 2016). In fact, taking part in CE can be quite laborious and the notion of consumption work highlights the time, skills and access needed to participate in circular consumption (Hobson et al., 2021). Existing research on CE skills are scarce, outdated and focused on only one practice at a time. The research gap of citizens’ CE skills has been identified by several researchers (e.g. Hobson et al., 2021; Wieser, 2019) and this thesis aims to fulfil the gap by adopting a qualitative approach. The data on which this research is based on, consists of semi-structured interviews with 20 Finnish citizens who have been active in implementing zero waste lifestyles and responsible consumption principles that are relevant for CE. By exploring their everyday practices related to CE, I identify six skill categories that the active citizens utilise to take part in CE. Particularly (1) manual skills were identified by the interviewees as central to performing circular activities. They include skills such as sewing and technical skills that enable repair and repurposing materials. The interviewees possess (2) divergent thinking skills and abilities to think creatively, for example about the ways you can use a certain item. They are also skilful in questioning consumption related social norms. (3) Research and communication skills are central for active citizens as they are trying to figure out the most sustainable options and inspire others with humour and positivity to take part in the circular economy. The interviewees describe often utilising (4) organising and prioritising skills that revolve around time management. They need to make decisions and prioritise certain actions that preferably are quite influential in terms of their carbon footprint. Moreover, when buying products second hand they should start looking for the items early and with rental options, the need should be anticipated and planned. Another identified set of skills are (5) household skills. They include maintenance skills of household goods and clothes, cooking skills to avoid food waste by using creativity and planning as well as recycling skills on sorting different fractions. The respondents also described (6) skills brought by experience. Knowledge on different second hand marketplaces and the skills to recognise good quality on materials and items enable circular practices. One of the main contributions of this thesis is consolidation of various sets of citizen skills relevant for the CE into a single framework. The findings further illustrate that consumer-citizens are doing a multitude of CE activities that require consumption work and certain skills. The findings provide information on how citizens engage and coordinate CE practices on the household level by prioritising and planning, a topic on which research has been lacking (Hobson et al., 2021). The skills of “thinking outside the box” are also a new set of skills that emerged from the interviews and it has a clear connection to the “unlearning” of noncircular consumption practices (Wieser, 2019). The identified skills could be taught more through formal and informal education channels, but it should be considered, how infrastructure, companies and services can ease people’s participation in CE. Findings of the thesis offer insight on the domestic reality of CE and how it could be improved in the Finnish context.
  • Moliner, Rafael (2019)
    Classical and rapid-acting antidepressant drugs have been shown to reinstate juvenile-like plasticity in the adult brain, allowing mature neuronal networks to rewire in an environmentally-driven/activity-dependent process. Indeed, antidepressant drugs gradually increase expression of brain-derived neurotrophic factor (BDNF) and can rapidly activate signaling of its high-affinity receptor TRKB. However, the exact mechanism of action underlying drug-induced restoration of juvenile-like plasticity remains poorly understood. In this study we first characterized acute effects of classical and rapid-acting antidepressant drugs on the interaction between TRKB and postsynaptic density (PSD) proteins PSD-93 and PSD-95 in vitro. PSD proteins constitute the core of synaptic complexes by anchoring receptors, ion channels, adhesion proteins and various signaling molecules, and are also involved in protein transport and cell surface localization. PSD proteins have in common their role as key regulators of synaptic structure and function, although PSD-93 and PSD-95 are associated with different functions during development and have opposing effects on the state of plasticity in individual synapses and neurons. Secondly, we investigated changes in mobility of TRKB in dendritic structures in response to treatment with antidepressant drugs in vitro. We found that antidepressant drugs decrease anchoring of TRKB with PSD-93 and PSD-95, and can rapidly increase TRKB turnover in dendritic spines. Our results contribute to the mechanistic model explaining drug-induced restoration of juvenile-like neuronal plasticity, and may provide a common basis for the effects of antidepressant drugs.
  • Vo, Quynh Le (2021)
    As the effects of climate change have become increasingly more visible in recent years, interest in climate adaptation has grown in both research and policy contexts. However, although Southeast Asia is one of the regions most vulnerable to climate change impacts, there has not yet been an effort to comprehensively track how Southeast Asian countries and communities are adapting to climate change. I apply a systematic review methodology developed for adaptation research to map adaptation responses identified in the Asian Development Bank’s (ADB) projects in Southeast Asia in 2016-2020. My results show that close to a fifth of the ADB’s adaptation projects in Southeast Asia is implemented in Cambodia, while Thailand and Timor-Leste are the least covered countries. In general, the characteristics of my examined projects are relatively similar to global adaptation trends. Flooding, drought, storms, and other heavy rainfall events are the most frequently addressed climate hazards by both the projects I examined as well as by UNFCCC climate fund projects and by adaptation responses documented in scientific papers. The sectors addressed and actors targeted by ADB projects were also typical to multilateral funding institutions, focusing on the agricultural and water sectors as well as national and local governments and farmers. Capacity building was the most frequent adaptation response category, indicating that adaptation implementation as delivered by the ADB is still in a relatively early phase in most Southeast Asian countries. In addition to results related to climate adaptation in Southeast Asia, I also demonstrate the applicability of a systematic review methodology for tracking climate change adaptation responses implemented by multilateral development banks, given sufficient information is made available on relevant projects.
  • Käyhkö, Janina (2017)
    Climate change causes climatic risks (hazard-exposure-vulnerability) that are experienced in agriculture as problems with increased precipitation, droughts, pest invasions and weather variability. Agriculture needs to adapt to these changing conditions to secure its continuation in future. It is the farmers, who in last hand take action for adaptation. Farmers are recognized as a stakeholder group in agricultural with plenty of skills to tackle varying weather conditions. In fact, farmers are already implementing adaptation measures, although it is not always driven by or aimed at climate change explicitly. Adaptation policies aimed at farm-scale are being planned and developed. The Intergovernmental Panel on Climate Change (IPCC) is the leading scientific source of adaptation policy recommendations. Currently it is recommending risk management approach for managing the known and unknown climatic risks that societies and sectors like agriculture are facing. In agriculture, for example, crop loss insurances are part of climate risk management. Farmers are making adaptation decisions at farm-scale based on their own beliefs and experiences, on information from variable sources, and guided by policies and legislation. The primary driver for taking adaptive action at farm, according to protection motivation theory (PMT), however, is the perception of risk – if the risk is assessed high enough and the adaptation is assessed possible. In this thesis, PMT and the theory of risk perception are used to explain farm-scale adaptation. Adaptation is examined as climate or weather variation driven adaptation measures implemented by farmers autonomously or guided by policies. A case study approach and stakeholder interviews were used because of the novelty of the study topic. By examining the case of ‘adaptation in Uusimaa agriculture’ through the perceptions of interviewed farmers and extension officers, an overview on farm-scale adaptation with its variety of influencing factors, and better understanding of risk perceptions as adaptation drivers is reached. Findings of the study show that farmers in Uusimaa are taking adaptation measures, but adaptation policies are not yet guiding adaptation at farm level and that farmers are divided by the ways they respond to climatic risks. Further studies on adaptation policies and agricultural adaptation should recognize the varying risk responses, the need for better adaptation policy guidance and farmers’ adaptation experiences and skills.
  • Peters, Dana (2021)
    Concern about global warming can lead to climate change anxiety, a form of anxiety characterized by excessive worry about the climate crisis and associated consequences on the natural world and human society. It has been suggested by previous research that humor can be used to manage feelings of anxiety. This study seeks to determine if this phenomenon can be applied specifically to climate change anxiety. The research combines a comprehensive literature review with an online survey that leveraged climate change themed internet memes as a proxy for humor to gather opinions about the intersections between these two topics. The survey data supplemented claims made by existing literature, indicating that climate change themed internet memes and humor in general can be useful coping mechanisms to mitigate feelings of climate anxiety. The survey was completed by 93 respondents; most of these participants were women, located in the US, and/or between the ages of 20 and 29. Results from the survey showed that people tend to feel best about their environmental anxiety when they are taking active steps to solve the problem. Conscious decisions such as reducing waste or participating in activist movements are easier to recognize and self-report than more passive coping skills. Reliance on humor was reported as a supplementary coping skill, but many respondents indicated that looking at humorous climate change themed memes did influence their feelings about climate change overall. The scope of this study was relatively small in scale, therefore the results presented in this thesis may not be indicative of broader social trends and likely require further research.
  • Pörsti, Saara Kyllikki (2022)
    Climate change have widespread increasing negative health impacts on urban residents. The impacts vary in different temporal and spatial dimensions and include health impacts such as increases in heat related illnesses, respiratory issues, and vector-borne diseases. Vulnerability and exposure to those impacts depend on different interacting factors from city level systems to individual characteristics. Papers that study how cities’ moderating factors impact on different climate change induced health impacts are an important part for setting adaptation policies. Little is known how city systems and system factors (social and physical environment and policy and planning) moderate climate change induced health impacts in cities and their role in different vulnerability and exposure outcomes. With an analytical framework that utilizes systems approach and follows conceptual framework that considers city systems as moderating factors to different vulnerability and exposure outcomes, this thesis answers the questions: How are the city systems and system factors, and climate risk elements (vulnerability, exposure) related? And what are the different types of interactions that lead to vulnerability and exposure outcomes? The main data of this qualitative case study is collected with 18 expert pair-interviews. The experts are selected from four residential areas that represent different municipalities in Helsinki and Turku. The interviews are transcribed and coded with Atlas.ti. The findings of this study emphasize that moderating factors have an impact on different vulnerability and exposure outcomes. The results also show that adaptation measures that would consider cities moderating factors, would have a significant impact on reduced exposure and vulnerability to begin with. Identification of different city system, climate risk and health impact pathway synergies doesn’t promote better adaptation policies as such. Better understanding of efficient adaptation policies require further studies of the consequences resulting from the policy decisions in physical and social environment in the long run.
  • Skogberg, Mikko (2020)
    Static floating chamber (FC) measurements of CH₄ and CO₂ fluxes from northern boreal river Kitinen were analyzed for this thesis. Measurements were carried out in summer 2018. Spatiotemporal variability was measured in the fluxes by comparing three chamber measuring locations: the opposite river banks and the middle of the river. Mean CO₂ flux estimate was 0.83±0.54 μmol CO₂ m⁻² s⁻¹ (mean ± SD, n = 73), consistent with other estimates for similar systems, with a corresponding k₆₀₀ CO₂ gas transfer velocity estimate of 17±9 cm h⁻¹ . Nonlinear modelling of CO₂ flux was found useful for analyzing floating chamber data from a river. The mean CH₄ flux was 0.0084±0.0047 μmol CH₄ m⁻² s⁻¹ , slightly lower than the median for different river systems in literature. The flux estimates were compared with eddy covariance measurements (EC). FC measurements are expected to give larger results, but additionally chambers are known to overestimate fluxes in flowing water. The comparison yielded chamber fluxes 3.3 and 2.9 times the EC median values for CO₂ and CH₄ respectively. Fluxes were similar between the three locations, and they peaked in late July for both gases in all loca- tions. Some differences over the river cross-section were observed. Discharge was significantly correlated to fluxes in the middle of the river, which could be explained by inhomogeneous flow. On two measuring days in early August, the mid-river CO₂ fluxes were three times those observed near the banks. The difference was also measured in methane. No clear cause was determined, but measuring spatial variation in surface water gas concentrations and flow could clarify the causes of similar observations in further studies.
  • Malkamäki, Henriikka (2023)
    Tropical coral reefs are amongst the most biodiverse and productive ecosystems on Earth. In recent decades, coral reefs have suffered an unprecedented decline in habitat-forming hard coral cover due to anthropogenic stressors, with severe impacts on ecosystem functioning and the provision of ecosystem services. Some of the pressing issues that coral reefs are facing can be mitigated through active reef restoration, such as coral transplantation, which aims to increase the hard coral cover, biodiversity, and structural complexity of a reef site. Studies on the passive benefits that increase the natural recovery potential and resilience of coral reefs following active restoration efforts remain scarce. In collaboration with Indo Ocean Project, this study aimed to compare benthic recruitment patterns between three coral sites located within the Nusa Penida Marine Protected Area, Indonesia. The reef sites included a restoration site with gardened Acropora corals, a natural site, and a rubble site that could serve as a restoration site. The experiment was conducted using standardized settlement tiles to measure and observe various response variables as indicators for the natural recovery potential and resilience capacity of the reef. The sites were also surveyed for their benthic reef cover, structural complexity, and fish abundance and community composition. The research objective was to find out how benthic recruitment patterns differ between restoration and natural reef sites, and why. The results confirm that active coral reef restoration efforts induce co-benefits in the benthic environment through enhanced structural complexity, leading to subsequent increases in overall fish abundance and particularly the number of herbivorous fish, and thus to a lower density of turf algae. These are promising findings for the later development of the reef site. The results do not imply that restoration efforts directly translate into enhanced coral recruitment or increases in crustose coralline algae abundance. However, the plentiful supply of spats observed at the restoration site indicates that local coral recruitment can improve over time after the transplanted corals have healed from transplantation stress and become fecund. Finally, the current rubble area can be expected to function as a restoration area in the future, as it appears to be within the reach of coral recruits. This study demonstrates that active coral reef restoration can yield benefits for the whole benthic ecosystem, and thereby aid recovery and strengthen resilience at localized scales. Given the accelerated rate of coral reef degradation, regular monitoring of restoration success is crucial to avoid loss of information regarding the benefits of active coral reef restoration for the fragile benthic ecosystem.
  • Honkanen, Julia (2023)
    Both microplastics (MPs, size 0.1 to 5 mm) and pharmaceuticals and personal care products (PPCPs) are ubiquitous in aquatic environments globally. Polystyrene microplastic (PS-MP) and diclofenac (DCF) are among the most widespread and commonly occurring MPs and PPCPs in the environment. Exposure to these chemicals in single has been reported to cause oxidative stress, immobilization, changes in growth and reproduction and even mortality in Daphnia magna. Moreover, MPs have the ability to act as a vector for PPCPs, and several laboratory studies have reported that PS-MP is able to absorb DCF. However, the combined toxicity of MPs and PPCPs remains largely unknown, especially as is the case for the combined toxicity of PS-MP and DCF in D. magna. In this study, D. magna was exposed to PS-MP and DCF, both in single and combined, at a concentration of 0.5 mg/L each. The aim was to assess the combined toxicity of the two, and determine whether they had a synergistic, additive, or antagonistic effect in D. magna. Whole organism endpoints monitored included mortality, immobilization, and moulting. Physiological endpoints monitored focused on oxidative stress and antioxidant defence, including reactive oxygen species (ROS), superoxidase dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST). The results indicated that both PS-MP and DCF in single were able to significantly alter D. magna antioxidant and biotransformation enzyme activities by inhibition of SOD and GST, while there were no observed impacts on the monitored whole organism endpoints or ROS and CAT. However, similar significant inhibition of SOD and GST was not observed in the combined exposure, which indicates that the combined toxicity of PS-MP and DCF in D. magna was most likely antagonistic. These results highlight that the combined toxicity of MPs and PPCPs is a complex topic that still needs further investigation to fully understand the complex interactions between MPs and PPCPs.
  • Lackman, Madeleine Helena (2022)
    Diabetes mellitus is an incurable disease caused by dysfunctional insulin signaling. The brown adipose tissue (BAT) serves as a hotspot for both lipid and glucose consumption and is thus an attractive target for treating metabolic diseases. Newly surfacing evidence suggest that the endothelial cells (ECs) lining the inner layer of vessels might regulate the morphology and function of adipose tissues. Several studies, including our own, suggest that the vessel density is negatively affected by metabolic diseases. As the BAT is an important organ for systemic lipid and glucose metabolism, and as the effects of metabolic diseases on BAT vessels are not adequately explored, I wanted to investigate how the BAT vasculature changes upon early time points of type 1 (T1D) and 2 (T2D) diabetes in this thesis work. To this end, I used mouse models with chemically induced T1D and genetic T2D and characterized these models with immunohistochemical analyses and immunoassays. To explore the transcriptomic landscapes of ECs and adipose stem cells (ASCs), I analyzed scRNAseq data of BAT stromal vascular fractions (SVF), focusing on changes in gene expression and EC-ASC interactions at a transcriptomic level. Also, by using a publicly available single-cell RNA sequencing (scRNAseq) dataset, I compared BAT SVF gene expression to complement the data resulting from our experiments. The results from this work reveal differential angiogenic responses in the T1D and T2D mouse models and open new avenues of research into how these different pathways are activated and how we can take advantage of these differences to treat diseases. All in all, this work will support the efforts in developing better options for future diabetes prevention, diagnosis, and care.
  • Avdonin, Savva (2021)
    Tiivistelmä – Referat – Abstract ROS or Reactive Oxygen Species can be found throughout all living organisms on the planet. Without ROS, processes, which are essential for the sustainment of most living organisms, such as respiration would not be possible. On the other hand, uncontrolled ROS generation can cause severe damage to the cellular structure. The family of ROS includes multiple compounds, which share a common trait of high chemical activity. ROS can be produced on demand by specific enzymes which are localized within cellular structures, such as membranes. One group of enzymes is called NADPH (Nicotinamide adenine dinucleotide phosphate) oxidases. These enzymes possess common structure which is composed of transmembrane region with multiple loop helixes and usually two or more terminal motifs, which are devised into regulatory EF-hand motifs and catalytic motifs. NADPH oxidases are essential ROS producers and can be found throughout most clades of living organism and are widely represented in different cellular compartments and distributed across different tissues in multicellular organisms. As an example, Nox family of NADPH oxidases can be found in human tissues and immune cells. Another common group of NADPH oxidases is respiratory burst oxidase homologues (RBOH) can be found in plants. Members of this group play important role in plant immune defense against pathogens. One example is AtRBOHD, which is expressed in Arabidopsis genus of plants. Upon activation, these enzymes are known to produce hydrogen peroxide (H2O2) as mean of antibacterial defense. These host defense mechanisms are known to be driven by different signaling molecules. It has been determined that in some examples of NADPH Oxidases, including Nox5 and RBOHD, the state of activation can be induced through the effects of Ca2+ ions. Moreover, it has been determined, that ROS-producing state of these NADPH oxidases is achieved through change of conformation. This change in conformation is attributed to the different modes of interaction of motifs of oxidases, which are dependent on concentration of bivalent cation Ca2+. Previous research regarding intramolecular interactions within specific NADPH oxidase- Nox5β has been performed by multiple research teams and different sources appear to contradict each other on the exact mode of interaction of Nox5β EF-hand upon presence of Ca2+. Therefore the exact interaction model of terminals of Nox5β is unclear. In addition, the effect of presence of Ca2+ on the interaction terminals in another representative of NADPH oxidases- AtRBOHD, which possess highly analogous molecular structure of catalytic C-terminus to Nox5β, has never been thoroughly studied, as well as interactive cross-compatibility of the C and N terminals from these two distinct species of NADPH oxidases. The objectives of this research are to analyze intramolecular interactions of N- and C- terminals in Arabidopsis RBOHD and Human Nox5β upon presence of ionic calcium, compare Ca2+-induced terminals interactions in said oxidases and to establish possible cross-compatibility of terminals in these two distinct NADPH oxidase species. Practical aspects of this research included cloning the C- and N- cytoplasmic regions of Nox5β and AtRBOHD into bacterial expression vectors utilizing the PIPE cloning method, heterologous production of epitope-tagged tails of NOX5β and RBOHD in E. Coli BL21 and finally in-vitro pull-down assays to analyse the interactions of the tails upon the presence of Ca2+ as well as interactive cross-compatibility of these tails. By utilizing methods mentioned above, this research has demonstrated that interactions of terminals motifs both in Nox5β and AtRBOHD are possible even in calcium-deprived environment, which was achieved through use calcium-binding agent (EDTA) and the effect of calcium on interactions of terminals both in RBOHD and Nox5β is very limited if not insignificant. This research has also demonstrated that the cross-compatible interactions between terminals of Nox5β and AtRBOHD are possible. Results of this research indicate a strong structural conservation within NADPH oxidases, which indicates similar intramolecular interaction mechanisms within two highly diverged species. These findings may prove to be useful as a background for the future research regarding ROS producing enzymes and evolutional conservation in structures of oxidases.
  • Lahtinen, Oskari (2022)
    Agriculture is emitting ~6.2 Gt CO2-Eq. annually, which accounts for ~12 % of the total annual net anthropogenic greenhouse gas (GHG) emissions globally. Agriculture emits N2O and CH4, and it is responsible globally for ~79% of N2O emissions and ~40% CH4 emissions. These emissions are vital since N2O and CH4 are 273- and 27-times greater GHG than CO2, respectively. There are many different food production systems developed to reduce these emissions. One of the most promising systems is agroforestry. Agroforestry is a complex system where trees and/or shrubs are interacting with crops and/or animals. Agroforestry is an old practice which can provide plenty of advantages, e.g., increased yields, increased biodiversity, and increased carbon sequestration. Therefore, the interest towards it has been increasing in the last decades. In this master’s thesis the different maize production systems in Zambia were studied. The comparison was conducted between low-input maize monoculture where only external input was maize seed for sowing; high-input maize monoculture where mineral fertilizers and seeds for sowing were used; and maize-Faidherbia albida agroforestry system where only external input was maize seed for sowing. The goal of this master’s thesis was to find out, which production system is having the lowest climate change potential in the Central Province of Zambia. To conduct this study, Life Cycle Assessment (LCA) -method was used. Two cases were used in LCA, i.e., Case 1 with functional unit (FU) of 1000 kg d.m. maize grain, and Case 2 with FU of 3 ha maize field. Also, four sensitivity analyses were conducted. The result from this study indicates that agroforestry system had the lowest climate change potential in both cases, and in most of the sensitivity analyses. Only exception was found in the sensitivity analysis where above-ground biomass of F. albida was substituting hydropower. In this sensitivity analysis the monoculture without external inputs had the lowest climate change potential. Since the food production in Zambia must increase in the future to reduce the hunger, the high-input system or agroforestry system are more favourable options as they produce higher crop yields. When taking the climate change potential into account, according to the results of this thesis, the agroforestry system provides more benefits. The results of this thesis can provide new knowledge which could be used in the future decision-making processes. Yet, in the future studies, more complex agroforestry systems with more sustainability pillars should be considered to provide improved information for decision-making.
  • Lindholm, Tanja (2015)
    Suomesta tavataan kaksi majavalajia: alkuperäinen euroopanmajava (Castor fiber) ja vieraslaji amerikanmajava (Castor canadensis). Euroopanmajava metsästettiin sukupuuttoon 1800–luvulla ja viimeinen euroopanmajava ammuttiin tiettävästi Sallan Eniönjoesta vuonna 1868. Vuonna 1935 aloitettiin majavien uudelleenistutukset 17 Norjasta tuodulla euroopanmajavalla. Vuonna 1937 Suomen majavakantaa vahvistettiin seitsemällä Amerikasta tuodulla amerikanmajavalla. Tahallisesta vieraslajin tuomisesta ei kuitenkaan ollut kyse, vaan vasta vuonna 1973 todettiin Castor-suvun koostuvan kahdesta eri lajista. Alueilla, joille istutettiin molempia lajeja, on jäljellä ainoastaan amerikanmajava. Syyt ovat edelleen epäselviä. Molempien lajien kannat ovat edelleen keskittyneet alkuperäisten istutusalueiden läheisyyteen, ja amerikanmajavakanta on muutamia poikkeuksia lukuun ottamatta saanut kasvaa ilman euroopanmajavan kilpailun vaikutusta. Jos lajien elinympäristövaatimukset ovat samat, eivät lajit voi esiintyä rinnakkain. Näin ollen on tärkeää tuntea molempien lajien elinympäristön käyttö mahdollisemman tarkkaan aluekohtaisesti ja ennakoida, johtaako majavalajien kohtaaminen kahden lajin rauhaisaan yhteiseloon vai mahdollisesti euroopanmajavan häviämiseen läntisestä Suomesta. Tutkimuksen tarkoituksena oli vertailla lajien elinympäristön vaatimuksia ja sitä kautta tuoda lisätietoa euroopanmajavan suojeluun. Tutkimusalueeksi valikoitui keskinen Pirkanmaan alue, missä lajien välinen etäisyys on ainoastaan 11 kilometriä linnuntietä. Aineisto koostuu vuoden 2013 Luonnonvarakeskuksen koordinoimista valtakunnallisten majavalaskentojen pesätiedoista sekä erilaisista paikkatietoaineistoista. Elinympäristönkäytön mallin muuttujat on tuotettu CORINE Land Cover 2012 (CLC2012), vuoden 2011 Valtakunnallisen Metsien Inventoinnin (VMI) ja Maanmittauslaitoksen maastotietokannan digitaalisiin paikkatietoaineistojen avulla. Alueelle luotiin 60 satunnaispistettä, jotka kuvaavat tarjolla olevaa elinympäristöä. Lajien elinympäristöjen käyttöä analysoitiin kahden logistisen regressioanalyysimallin avulla, joista ensimmäisessä tarkastellaan ydinaluetta (50m) ja toisessa elinpiiriä (1km). Analyyseissä verrattiin lajeja keskenään sekä satunnaispisteisiin. Ennen regressioanalyysejä tarkasteltiin muuttujien kolineaarisuutta Variance Inflation Factor:in (VIF) avulla, jonka jälkeen tarkasteltiin aineiston yhteensopivuuttaa mallin kanssa Akaiken informaatiokriteerin (AIC) avulla. Pienin AIC ilmaisee parhaan mallin korkeimman selitysasteen ja mallin yksinkertaisuuden (parsimonisuuden) kompromissina. Ydinalueella ei havaittu merkitseviä eroja elinympäristön vaatimuksissa lajien välillä. Majavien elinympäristönkäyttö ei kuitenkaan ollut satunnaista. Kuusen tilavuudella oli positiivinen vaikutus euroopanmajavan esiintymiseen ja lehtipuiden tilavuudella oli positiivinen vaikutus amerikanmajavan esiintymiseen verrattuna tarjolla olevaan ympäristöön. Elinpiirianalyyseissä lajien välillä havaittiin merkitseviä eroja, joissa euroopanmajava esiintyi alueilla, missä kuusen tilavuus ja sekametsän osuus oli suurempi verrattuna amerikanmajavan elinpiiriin. Kasvavalla kuusen tilavuudella, sekametsän osuudella sekä vesistöjen määrällä oli positiivinen vaikutus euroopanmajavan esiintymiseen ja rakennetuilla alueilla negatiivinen vaikutus euroopanmajavan esiintymiseen verrattaessa tarjolla olevaan ympäristöön. Amerikanmajavan elinympäristön käyttö ei poikennut satunnaisesta. Tulokset saattavat heijastaa rantavyöhykkeen metsäsukkession eri vaiheita, mutta on huomattava, että lajien välillä oli merkittäviä eroja. Elinympäristön muuttujat selittivät huomattavasti enemmän euroopanmajavan esiintymistä alueella verrattuna amerikanmajavaan. Toisin sanoen euroopanmajavan elinympäristön vaatimukset ovat spesifimmät/tarkemmat/ominaisemmat. Tulosten avulla on mahdollista ennustaa niin amerikanmajavan leviämistä alueella kuin hyödyntää tietoja euroopanmajavalle tärkeiden elinympäristöjen suojelussa.
  • Malmsten, Annina Maria (2023)
    Promoting carbon sequestration and storage is an important part of climate change mitigation. Soils play a prominent role in this, as they contain the largest terrestrial carbon pools. Urban soils have been shown to contain significant amounts of carbon, and thus, urban green spaces have the potential to contribute to climate regulation through soil carbon sequestration and storage. Many green spaces in cities consist of managed lawns containing significant amounts of soil organic carbon, although management activities such as mowing can also be a source of carbon emissions. A low-maintenance alternative to lawns is urban meadows. The benefits in terms of soil carbon sequestration in urban meadows, however, are still poorly documented. This study aims to contribute to an increased understanding of the ecosystem services urban meadows provide, which is valuable in the planning of urban green infrastructure. I quantified soil organic carbon content in 140 urban meadows of different land use types in the Helsinki Metropolitan Area to determine their value in terms of carbon storage and to compare this with the soil carbon storage in highly managed urban lawns. The meadow types explored included valuable grasslands, which have special nature or cultural values, landscape meadows, road verge grasslands, and rocky outcrops. Soil samples were taken from a depth of 0–10 cm using a soil corer. The soil organic matter content and bulk density were measured. Existing data from the soils of city park lawns in Helsinki were used for comparison in the analysis. The soil organic carbon content in the different meadows, as well as in the lawns, was then analysed using land use type and site productivity as explanatory variables. Results show that park lawn soils have a significantly higher carbon density (kg C per square meter) than any of the meadow types. Out of the meadow sites, valuable grasslands had the highest carbon density. The higher carbon content in park lawn soils may be due to increased productivity due to frequent mowing, as well as the fact that these lawns were likely established on nutrient-rich soil. Interestingly, the highest %C was detected in rocky sites. However, the total carbon stocks of rocky sites are lower due to the soil cover being shallow and large portions of the sites not having soil cover at all. To answer the question of whether a lawn should be converted into a meadow in hopes of increasing carbon sequestration and storage, future studies should focus on meadows that were formerly lawns, and that had the same or similar initial conditions as a typical lawn.
  • Yrjölä, Veikko (2023)
    While the effects of agricultural land use on biodiversity are beginning to unravel in Europe and North America, Africa remains poorly studied. Biodiversity in a broad sense provides ecosystem functioning and services, whose importance has become obvious to humankind in the quickly changing modern world. In Ghana, the practice of mango farming continues to grow in popularity due to suitable climate and potential source of livelihood. With increased demand and production of mango, natural habitats, namely savannahs, are being converted to plantations. The effects of such habitat conversion on local biodiversity are unknown for most taxa, thus providing an interesting study system for biodiversity research. Given the direct relation between functional diversity and ecosystem services, in this work I compare the taxonomic and functional diversity of ground-living spiders between mango orchards and savannah. I chose spiders (Arthropoda; Araneae) as model organisms as they critically contribute to several ecosystem services, such as biological pest control and nitrogen cycling, while being ubiquitous and abundant, thus easy to collect in the field. Spiders were captured with pitfall traps from six mango and four savannah areas in the Northern region of Ghana. A total of 424 individuals and 53 (morpho)species were identified and counted. Additionally, six morphological and four ecological traits were quantified for each (morpho)species. With these data, I calculated taxonomic richness and evenness, functional richness, dispersion, and evenness, and beta diversity of the different assemblages in the R environment. These metrics were then compared between spiders collected from mango orchards and savannah. Mango orchards showed lower taxonomic and functional evenness than savannah, contrary to all other alpha diversity measures. The two habitat types share many of the same diversity of ground-living spiders, but species and traits are distributed less evenly in mango orchards due to incomplete niche differentiation between species. Both taxonomic and functional beta diversity were significantly different between habitat types indicating that mango orchards sustain a similar richness of species as savannah, but the species composition is different. In conclusion, mango orchards have the potential to conserve some aspects of the original diversity, but species composition and the way species interact are substantially different. We should strive to find the best practices to produce mango without radically changing the natural biodiversity patterns.
  • Pykäri, Janina (2022)
    Light is crucial for aquatic ecosystems, as photosynthesis supports the higher trophic levels. Light attenuates in water due to absorption and scattering by optically active substances (OAS), the main ones in coastal environments being chlorophyll-a (chl-a), particulate matter and coloured dissolved organic matter (CDOM). Light attenuation measurements are also important indicators of many environmental changes. Traditionally, Secchi depth has been used to monitor changes in light attenuation. However, Secchi depth (ZS) is a not an accurate estimate of light attenuation, and conversion to light attenuation coefficient (Kd) is needed to study light conditions as aquatic organisms observe them. Therefore, calibration between methods is important. In this study, light attenuation was estimated with Secchi disc, a light meter and light loggers to scrutinize the possibilities of autonomous measurements in this context. The aims of the study were 1) to compare three methods for estimating light attenuation and 2) to identify the environmental drivers affecting the relationships and accuracy of these methods, and 3) to assess the possibility of using conductivity as a proxy for light attenuation. The main hypotheses were that the differences in conversion between ZS and the two sensor-based methods in different concentrations of optically active substances can be explained by contribution of scattering to light attenuation, and that variation in different Kd-estimates is due to the different measurement spectra. The effect of three OASs (chl-a, particulate matter, CDOM) on differences among light attenuation estimates were quantified in Pohjanpitäjänlahti bay. Light attenuation was mainly controlled by CDOM, followed by particulate matter and chl-a. Conductivity was found to be a good proxy for light attenuation. However, there was a mixed signal if the differences among methods could be explained by OAS concentrations or conductivity, as the hypotheses were supported with one device pair but not with the other. Therefore, the differences among light measurement methods might stem from the characteristics of the devices or measurement errors. However, all the methods were found suitable for tracking changes in light attenuation and a summary table of the advantages and disadvantages of each method is presented to help choose a suitable method to estimate light attenuation e.g., in future studies or environmental monitoring.
  • Oikkonen, Jaana (2012)
    Genome wide linkage and association methods are used to map genes affecting traits with genetic predisposition. In this thesis, I compare the methods suitable for quantitative trait mapping in complex, extended pedigrees. As a case study, gene-mapping study of musical aptitude is performed with these methods. Linkage analysis methods are developed for family studies. However, only a few methods are suitable for extended families with a quantitative trait. Three linkage programs were successfully applied for such data in this study. These programs are the SOLAR, JPSGCS and KELVIN. All of these three programs are based on different methods and thus, the same calculations are not repeated. SOLAR is based on the variance components method, JPSGCS on a graphical method and KELVIN on the Bayesian method. Association analysis is also difficult to implement for large pedigrees, because it is best suited for case-control data. Fortunately, methods are extended also for family-based studies. Here, a genomic control method was used to correct for the familial relationships. The method evaluates the relatedness from the whole genome data and the association tests are corrected for the relatedness rates. This method was implemented from the GenAbel program. As a case study, these methods were applied to a musical aptitude study. The musical aptitude is here understood as an ability to perceive the melody, harmony and rhythm of music, and to recognize structures in set of sounds. These abilities were tested with Carl Seashore s tests for pitch and time and Kai Karma's test for auditory structuring. The data consists of 107 pedigrees and 93 sporadic subjects, comprising in total of 915 individuals. Each family includes 2 - 50 individuals. These individuals were genotyped with a SNP chip for over 700,00 SNPs. The linkage analyses revealed several promising loci for the musical aptitude. The best result was located in 4q12 and it was found with all of the three linkage programs. Most of the other results could also be identified with multiple programs, but some differences also occurred. However, none of the findings could be discovered with association analysis, probably due to a too small sample size.