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Variation in food resources can result in dramatic fluctuations in the body condition of animals dependent on those resources. Decreases in body mass can disrupt patterns of energy allocation and impose stress, thereby altering immune function. In this study we investigated links between changes in body mass of captive cane toads (Rhinella marina), their circulating white blood cell populations, and their performance in immune assays. Captive toads that lost weight over a 3-month period had increased levels of monocytes and heterophils and reduced levels of eosinophils. Basophil and lymphocyte levels were unrelated to changes in mass. Because individuals that lost mass had higher heterophil levels but stable lymphocyte levels, the ratio of these cell types was also higher, partially consistent with a stress response. Phagocytic ability of whole blood was higher in toads that lost mass, due to increased circulating levels of phagocytic cells. Other measures of immune performance were unrelated to mass change. These results highlight the challenges faced by invasive species as they expand their range into novel environments which may impose substantial seasonal changes in food availability that were not present in the native range. Individuals facing energy restrictions may shift their immune function towards more economical and general avenues of combating pathogens.

The characteristic blood flow patterns through the major vessels can serve as indicator of cardiovascular health, where pathologies in the cardiovascular system express themselves in form of unphysiolocial flow conditions. Implantable sensor systems in conjunction with machine learning algorithms provide powerful tools to improve healthcare by long-term monitoring of crucial markers while reducing costs through automated diagnostic tasks. This thesis describes methods for blood flow measurement in large vessels and how these can be incorporated in wireless implants for long-term remote patient monitoring and postoperative care. The development process of an implantable magnetic blood flow sensor utilizing permanent magnets in a circular Halbach array configuration is outlined. This design enables fully batteryless and wireless operation using the user's smartphone for transcutaneous communication and power transfer. A machine learning framework is proposed which performs automated diagnostic tasks based on the sensor data without user interaction through unsupervised learning algorithms.

United Bank of India, 507 R. B. C. Road, Garifa, North 24-Parganas Department of Chemistry, University of Kalyani, Kalyani-741 235 Department of Chemistry, Vivekananda Mission Mahavidyalaya, Viveknagar, P.O. Chaitanyapur (Haldia)-721 645 Manuscript received 9 June 1992, revised 22 October 1992, accepted 2 December 1992 ln order to understand the nature of ion-solvent interactions and structural changes of the solvent mixtures associated with the addition of ions, conductance measurements of the tetraalkylammonium halides in ethanol + water mixtures were made. The results have been analysed using the Fuoss equations. In absence of transference number values, the single ion values of tetraalkylammonium ions at 16.4, 34.4, 54.1 and 76 wt% of ethanol have been calculated using reference electrolyte method taking Bu4NBPh4 as the electrolyte. The variation of \(\Lambda\)o and \(\Lambda\)oηo or \(\Lambda\)o±ηo With solvent composition has been interpreted in terms of structural changes associated with the addition of electrolytes. Most of the electrolytes can be regarded to be associated in the solvent mixtures.

It has been increasingly aware to the world today that reserves of fossil fuels are limited and their use has serious environmental side effects. Encouraged by this realization was the evolution of the use of cleaner alternative energy, among which Dye-sensitized solar cells (DSCs) are potentially attractive candidates for the lower cost of producing devices which convert an abundant amount of energy from the sun into electricity. Dye-sensitizer in DSCs plays a crucial role as the chlorophyll in plants; to harvest solar light and transfer the energy via electron transfer to a suitable material (TiO2 in this case) to produce electricity. The topic of interest for this thesis is to further enhance the photovoltaic performance and the robustness of DSCs by tuning the optical properties of the dye-sensitizer (Ruthenium complex, in this case) using several strategies including an extension of the π-conjugation system, an introduction of antenna molecules and a modification of the Ru-complex structure. This work focuses on the DSC device fabrication and photovoltaic characterization in order to investigate more insight into structure-property-device performance relationship. New benchmarks for high performance DSCs with ruthenium complex sensitizers with π-extension in their ancillary ligands were presented. The overall conversion efficiency of 9.6% and 8.5% have been achieved with Ru-based sensitizer containing ethylenedioxythiophene, using low-volatile electrolyte and solvent-free electrolyte, respectively. The Rusensitizer functionalized with hexylthio-bithiophene unit exhibited a conversion efficiency of 9.4% with low-volatile electrolyte. All these devices showed good stability under prolonged light soaking at 60 °C. Extending π-conjugation of the anchoring ligand with thiophene units in monoleptic Ru-sensitizer also yields an impressive conversion efficiency of 6.1% using 3-µm-thin mesoporous TiO2 film in corporate with low-volatile electrolyte. DSC devices based on ruthenium sensitizers functionalized with thienothiophene- and EDOT-conjugated bridge, together with carbazole moiety on the ancillary ligands were found efficient with conversion efficiencies of 9.4% and 9.6%, respectively, in presence of a volatile electrolyte. The carbazole-functionalized ruthenium-based DCSs also performed excellently in the stability test using a low-volatile electrolyte. Furthermore, the Ru-complexes synthesized by click-chemistry in association with triazole-derivative moieties were successfully used as DCS sensitizers. DSC devices sensitized with these dyes provided the overall conversion efficiency close to 10% with volatile electrolyte. Further studies with solvent-free electrolyte showed notable device stability under extending full sunlight intensity at 60 °C. The results presented here provide a fertile base for further investigation, which will focus on improving the spectral response of ruthenium dye-sensitizer to full sunlight by searching for new strategies to modify the sensitizer with more efficient functional groups. The target is to reach higher conversion efficiency of DSC devices while retaining their stability under standard reporting conditions.

The seeds of \(Trigonella\) \(cornioulata\), Linn. yields three steroidal sapogenins in the form of saponins. One of the sapogenins present in 70% yield of the total genins has been identified as yuccagenin in adqition to diosgenin already reported. The third sapogenin is present in traces only.

This thesis is organized into three main sections, and is concerned with the design and synthesis of novel ionic liquids (ILs), and their associated electrochemical applications. In the first section, a general introduction to the field of ionic liquids is presented, followed by the synthesis and characterization details of all novel compounds used in the study. The second section summarizes work done on the development of more stable dye-sensitized solar cells (DSCs). An introduction to the field of photovoltaics and DSCs is first delivered in Chapter 3, which is followed by two chapters of original work on ionic liqiud-based electrolytes for DSC applications. In Chapter 4, it is shown that novel triazolium-based ionic liquids can be used to fabricate dye-sensitized solar cells, giving power conversion efficiencies of up to 6.00 %. The ionic liquid-based electrolytes are found to be compatible with a range of organic and inorganic photosensitizers, although the ruthenium-based dye (coded C106) exhibits the best performance. A device employing one of these newly-developed electrolytes is also shown to be very stable, retaining ca. 90% of its initial performance even after 1000 hours of continuous full sun illumination at 60 â ŠC. In Chapter 5, we focus on the development of stable porphyrin-sensitized solar cells, using IL-based electrolytes. Our studies reveal that the long-term stability of porphyrin-based DSCs are highly dependent on additives in the electrolyte. In particular, it is found that the additive, guanidinium thiocyanate, is essential for the preparation of long-lived devices. It is also shown that the beneficial effect of this additive originates from the thiocyanate anion, rather than the guanidinium cation. The third section of this thesis deals with the ionic liquid-catalyzed electroï¿Œchemical reduction of carbon dioxide. Following a general introduction on carbon dioxide mitigation using ionic liquids (Chapter 6), the results of our work in this area are presented in Chapter 7. Our studies reveal that not all ionic liquids are stable at the potentials required for CO2 reduction. However, the imidazolium-based salts generally perform quite well. The catalytic effect of the IL is found to mainly stem from the cation, with the anion playing a somewhat secondary role. Our results also demonstrate that substitutions on the imidazolium ring can have a huge impact on catalysis. Product analysis shows that the best-performing catalyst produces carbon monoxide as the dominant product, with Faradaic efficiencies of between 70 to 80 %.

Dataset associated with the publication "Environmental and economic potential of decentralised electrocatalytic ammonia synthesis powered by solar energy" by Sebastiano C. D'Angelo, Antonio J. Martín, Selene Cobo, Diego Freire-Ordóñez, Gonzalo Guillén-Gosálbez, and Javier Pérez-Ramírez, available at https://doi.org/10.1039/D2EE02683J. The dataset includes the numeric data required to plot all the figures embedded in the main manuscript and in the Electronic Supplementary Information (ESI). The structure of the dataset is here elucidated sheet by sheet: GeneralParameters: numerical values for the scaled functional unit used in the study, the world population value adopted, and the three voltage efficiencies assumed in different parts of the study. AL_BaseCase_SensECE: numerical values associated with the results for the ammonia leaf scenarios adopting a voltage efficiency of 63% (base case) and a Faradaic efficiency varying from 1% to 100%; highest, average, and lowest capacity factors for the solar power production were here used. The ammonia leaf configuration here assessed is the one including solar panels, electrolyzer, and fuel cell as key components. The results report all the ReCiPe 2016 (hierarchical approach) midpoints and endpoints and the values for the assessed planetary boundaries; the levelised cost of ammonia (LCOA) is reported, as well. AL_EtaV75_SensECE: this sheet has the structure as the previous one, but includes the results for the ammonia leaf scenario using 75% voltage efficiency, instead of 63%. The remaining assumptions do not deviate from the base case. AL_Eta100_SensECE: this sheet has the structure as the previous one, but includes the results for the ammonia leaf scenario using 100% voltage efficiency, instead of 63%. The remaining assumptions do not deviate from the base case. AL_NoFC_H2Vented_SensECE: this sheet has the same structure as the sheet "AL_BaseCase_SensECE", but includes the ammonia leaf scenario using a configuration with no fuel cell. The hydrogen by-product was here considered vented to the air. The remaining assumptions do not deviate from the base case. AL_NoFC_H2Subst_SensECE: this sheet has the same structure as the sheet "AL_BaseCase_SensECE", but includes the ammonia leaf scenario using a configuration with no fuel cell. The hydrogen by-product was here considered substituting the production of an equivalent quantity from a water electrolyzer deployed in the same location as the ammonia leaf. The remaining assumptions do not deviate from the base case. AL_BaseCase_SpatAnal_BreakFEff: numerical results for the ammonia leaf base case scenario stemming from the spatial analysis performed on a global grid of 1140 points. The yearly average capacity factors for the solar panels at each location are included, and the results portraying the breakeven Faradaic efficiency for the indicators climate change - CO2 concentration, global warming, human health, and levelised cost of ammonia were included. The assumptions for the voltage efficiency and the other parameters correspond to the base case. AL_BaseCase_SpatAnal_AbsValues: numerical results for the ammonia leaf scenarios using the base case state-of-the-art (34%) and 100% Faradaic efficiency, as well as the base case voltage efficiency of 63%. The same metrics as the previous sheet are reported. The structure of the sheet is the same as the previous one. AL_BaseCase_Breakdowns: breakdown of the same four indicators as the previous sheet for the best and worst combination of Faradaic efficiency and solar panels capacity factors, i.e., 34% Faradaic efficiency and 6% capacity factor on one side and 100% Faradaic efficiency and 26% capacity factor on the other side. The breakdown is divided into solar panels, electrolyser, fuel cell, and other elements. A further breakdown of the levelised cost of ammonia (LCOA) into capital expenditure (CAPEX) and operating expenditure (OPEX) is provided, as well. The voltage efficiency is the same as the base case, as well as the other parameters. AL_BaseCase_CAPEXSens: numerical results for the levelised cost of ammonia (LCOA) in dependence of the sensitivity on the capital expenditure (CAPEX) for the ammonia leaf configuration assessed in the base case. Two cases assuming state-of-the-art (34%) and 100% Faradaic efficiency were assumed, and lowest, average, and highest capacity factor are included. The remaining parameters do not deviate from the base case configuration. AL_gHB_BestMap: numerical results to produce the map showing the best technology between ammonia leaf (AL) and green Haber-Bosch (gHB) in the category climate change - CO2 concentration for all the assessed locations. column D shows the share of safe operating space (%SOS) for each location, while column E shows which technology was selected, where 1 is ammonia leaf and 2 is green HB. AL_BaseCase_Sensitivity: percentual variation of the results obtained assuming the base configuration ammonia leaf for a state-of-the-art Faradaic efficiency and an average capacity factor for the solar panels. The varied parameters include the voltage efficiency (columns C-D-E), the levelised cost of electricity (columns G-H-I), the electrolyser cost (columns K-L-M), the fuel cell cost (columns O-P-Q), the electrolyser environmental impact (columns S-T-U), and the fuel cell environmental impact (columns W-X-Y). CompTech_BaseCase: environmental and economic metrics characterizing the assessed Haber-Bosch scenarios (business as usual, BAU; blue Haber-Bosch; green Haber-Bosch for lowest, average, and highest solar panels capacity factor; BAU assuming natural gas spot prices in Europe in August 2022). The reported metrics are the ReCiPe 2016 (hierarchical approach) midpoints and endpoints, the planetary boundaries, and the levelised cost of ammonia (LCOA). CompTech_EtaV75: this sheet has the same structure as the previous one, but the hydrogen electrolyser used for the green Haber-Bosch scenarios was assumed to have a 10% stack efficiency improvement. The remaining parameters are the same. CompTech_EtaV100: this sheet has the same structure as the previous one, but the hydrogen electrolyser used for the green Haber-Bosch scenarios was assumed to have a 100% stack efficiency. The remaining parameters are the same. CompValues_Fig1: numerical values for yearly global warming impacts of a selection of countries, as well as for the yearly human health impacts of selected diseases and catastrophic events.

Human-driven climate disruption and widespread energy poverty are among the major challenges of our time (Alstone, 2015; SEAll, 2017). An estimated 1.1 billion people remain without access to modern energy, most of whom rely on biomass and fossil fuels for lighting, cooking, and heating — energy sources that lead to indoor air pollution and global warming (SEAll, 2017; WHO, 2016). Policy makers, entrepreneurs, and researchers across the globe place high hopes on renewable energy, particularly off-grid solar, to provide cheap and clean energy to those without access to the electric grid. The hope is that off-grid solar can reduce harmful and warming emissions from kerosene combustion and, at the same time, improve access to modern energy for unelectrified households. Despite this excitement, there is still little empirical evidence that there is demand for this technology solution, that it brings about the hoped for environmental and health effects, and that it confers private returns. It seems particularly relevant to evaluate the impact of this technology in a real-world setting since, previously, both private and environmental gains from novel technologies, such as cookstoves, have been overestimated (Hanna, Duflo & Greenstone, 2016). This thesis investigates take-up, use, and impacts of off-grid solar lighting in rural Kenya. To this end we conducted a randomized control trial with over 1,400 households. We begin by providing an analysis of the demand for solar lights, their environmental and health effects as well as the private returns to households (Chapter 2, joint work with I. Günther). We find that access to a solar light leads to a reduction in kerosene consumption of over 1.4 liters per month, curbing emissions at a cost of less than USD 6 per ton of CO_{2} equivalent. This cost is low compared with the frequently cited Social Cost of Carbon (SCC) of USD 50 per ton of CO_{2}equivalent (Revesz et al., 2017; IWG, 2015). Children's symptoms related to dry eye disease and respiratory illnesses reduce by about a fourth standard deviation and a third standard deviation, respectively. In addition, households save around 2-3% of their monthly cash expenditure. However, we do not find any effect on children's test scores. Finally, we find that reducing transaction costs increases demand 19% to 44% at a market price of USD 9, however, large price subsidies (over 55%) are needed to increase adoption rates to 70%. Price also does not seem to affect use. We conclude this chapter by suggesting that environmental and health effects combined with the high price sensitivity of demand and the fact that subsidies do not decrease use might justify subsidies in some settings. The impact of solar lights on rural households and their environment depends heavily on whether households actually use them over time, which, as can be seen from the example of clean cookstoves, is not always the case (Hanna, Duflo & Greenstone, 2016). Measuring technology usage can be challenging, especially if respondents believe that it is socially desirable to use a device (social desirability bias). In this case, they might overreport use, which would lead to biased results. This bias has been found in several studies of technology adoption in developing countries (Wilson et al., 2016; Thomas et al., 2013). To address social desirability bias and other measurement issues, we used sensors to measure the use of solar lights. The sensors were developed for this study by an engineering team. Chapter 3 (joint work with I. Günther and Y. Borofsky) focuses on information provided by sensor data. Specifically, we deployed sensors to gather an objective measure of solar light use. We then compared this data with survey data in order to analyze the extent to which survey data is limited by systematic and/or random error and discuss what type of questions provided more accurate answers. We learn from sensor data that households used solar lights almost every day, for four hours per day on average, mostly in the evening and the morning hours. Furthermore, we find that, on average, self-reported estimates of solar light use are very similar to sensor measurements, however, the correlation of estimates at the individual household level are weak, suggesting that random errors are large. Our findings indicate that households that used the solar lights infrequently were more likely to overreport, whereas those who used them a lot were more likely to underreport use. We also find that asking about general usage provided more accurate information than asking about disaggregated use for each hour of the day. Finally, and as the Hawthorne effect would predict, frequent visits from surveyors to a random subsample increased solar light use initially, but it had no long-term effects. Due to the novelty of both affordable solar lighting and the sensors used, this study is the first to both use sensors to study solar light use and compare sensor data with survey data at a large scale. One of the key findings of Chapter 2 is that emissions reductions might justify subsidizing solar lights in some contexts, however, temporary subsidies can have complex and contradictory effects on take-up and use. Chapter 4 discusses the direct and indirect implications of subsidies on take-up and use in more detail. We begin by analyzing how subsidies affect use. They could lead to lower use, since paying a lower price might lead adopters to value the product less (sunk cost effect), or they might lead to poor targeting since households that do not actually need the subsidy might use it to purchase the product (selection effect). Social interaction effects could also affect adoption, as people might learn from early adopters or imitate them. We find that subsidies sharply increase demand for solar lights without compromising use, thus we do not find evidence for sunk cost or selection effects. Further, our results suggest that social interaction effects might increase the price sensitivity of demand, whereby demand decreases among households that received an offer to purchase at a high price, but tends to increase among households that received the low price. These findings have two implications. First, they suggest that social learning about the limited private returns are more likely than imitation, since in the latter case we would have expected to see increased adoption across the board. Second, they imply that social interaction effects are complements for subsidies, but that they do not increase adoption on their own. To summarize, we find that in our setting solar lights are used a lot and substantially reduce kerosene use. They reduce warming emissions at a low cost and provide cheaper and better quality light to rural households. Moreover, we observe that further price reductions are needed to increase adoption rates above 50% and that subsidies do not affect use. Taken together, these findings suggest that subsidizing off-grid solar can be justified in some settings.

Over the past few decades, the debates have shifted from whether to how Computer Science (CS) should be introduced into formal education. Given the diverse ways to introduce CS into formal education, and the struggles many countries have faced, considerably more research is required to provide a framework for effective CS curricular reforms. Effectiveness implies implementing a scalable reform and teacher Professional Development (PD) program that promotes teachers' acceptance of the discipline and sustains changes in their practices to affect student learning and perception. This thesis investigated these prerequisites within a mandatory curricular reform project in the Canton of Vaud in Switzerland. The project introduces CS as a part of Digital Education in the K-12 curriculum through the collaboration between 4 major institutions in a Research Practice Partnership (RPP). The RPP brought together the main reform stakeholders to conceive, pilot and deploy the CS curriculum and teacher PD program to all 93 schools in the region (130'000 students, 9'000 teachers) within a framework that looks to address existing barriers to affecting sustained changes in teachers' practices. In this thesis we focus on the mandatory primary school Digital Education curricular reform where teachers teach all subjects and are generally less interested in teaching CS than specialised teachers. The thesis examines all phases of the reform, from conception to widespread deployment, with inputs from coordinators, trainers, teachers, students and researchers in order to: - Understand how to effectively co-construct a CS PD program with key stakeholders and propose recommendations to improve the outcomes of RPP initiatives. The findings draw from 3 studies where we interviewed project coordinators, trainers, teachers and researchers. - Validate the effectiveness of the proposed curricular reform framework and PD program in terms of teacher perception, short-term and sustained adoption. The validation relies on 3 studies following 350 pilot grades 1-4 teachers for four years, of which two after their PD program. Additional studies then investigated (i) the factors that influence teachers' decision to teach a given CS pedagogical activity through adoption modelling, and (ii) solutions to improve teachers' acceptance of CS. - Investigate how the reform contributes to equity in terms of student perception and learning in one study involving 4 data collections with approximately 13'500 grades 3-6 student- and 320 teacher respondents. Two of these data collections evaluated student learning using the competent Computational Thinking (CT) test, a CT-concepts test we designed and validated through 3 main studies with data from 2'700 grade 3-6 students. - Validate the effectiveness of our adapted cascade deployment model to spread the PD program to all teachers in the region in our final study. The validation concerns the first of three deployment phases and involves 14 teacher-trainers, 700 grades 1-4 teachers and a comparison with the pilot program's outcomes. To conclude, this thesis contributes to validating longitudinally, at a large scale, and through multiple studies, a framework for the sustainable and scalable implementation of CS curricular reforms and their PD program. This framework provides insight which are useful for all stakeholders involved in CS curricular reforms, and will hopefully increase the likelihood of their reforms succeeding.

The master's thesis project "Future Learning Space" is embedded into the context of the contemporary learning environment at ETH Zurich. The thesis advocates for the preservation and re-use of the Huber Pavilions on ETH Campus Hönggerberg, which coincidentally were being demolished at the same time. While exploring the question “what makes a healthy learning environment?”, the diploma project tests the limits to collaborate with the existing network of stakeholders at ETH, from a student's perspective. The diploma thesis concludes with a 1:1 mock-up, a building site and -permit for the construction of a research object next to the HIL building, allowing students of the following semesters to continue the legacy of the Huber Pavilions and build their own learning environment.