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Robustness of critical soil moisture to curve-fitting methods and its variability with soil depth, soil texture, and climatic conditions: insights from lysimeter data in Germany
No full textAbstract
Actual evapotranspiration (ETa) is a vital terrestrial ecosystem process that links water, energy, and carbon cycles. ETa can be limited by either energy or water availability. The transition between water- and energy-limited regimes is related to soil moisture and is often characterized as a threshold, denoted as critical soil moisture threshold (θcrit). However, the determination of θcrit is subject to uncertainties due to the different methods used to evaluate the relationship between ETa and soil moisture (SM), such as SM depths, definitions of ETa and curve fitting functions. Typically, surface SM is used to identify θcrit as it is easily accessible and assumed to represent root zone SM status. Weighable lysimeter technology provides a unique opportunity to assess the role of root zone SM on the transition between water and energy limited ETa. It is widely regarded as the gold standard for measuring in-situ ET, and at the same time allows for in-situ SM measurements at different depths. In this study, we estimated θcrit using in situ SM measurements at 10 cm depth and root zone SM by vertically integrating in situ SM (0–60 cm) observations. In addition, we applied three different definitions of relative evapotranspiration (evaporative fraction, the ratio of ETa to grass reference evapotranspiration and the ratio of actual ETa to calculated potential evapotranspiration) as well as two different fitting curves to investigate the sensitivities of θcrit. We found robust θcrit estimates across different definitions and fitting curve methods, but the estimates were significantly higher for root zone than for surface θcrit. Our results also highlight the high correlation (0.83) between root zone and surface θcrit. However, the relation between both values is not unique since it depends on the actual moisture profile and plant root system and, herewith, on the soil type and previous weather conditions. We further observed that both surface and root zone θcrit decreased with increasing sand fraction. Under changing climatic conditions but with identical soil and ecosystem types, both surface and root zone θcrit decreased with increasing aridity. Additionally, we found that using the midpoint between field capacity and wilting point provides a reliable range of root zone θcrit for a given soil texture.Abstract
Actual evapotranspiration (ETa) is a vital terrestrial ecosystem process that links water, energy, and carbon cycles. ETa can be limited by either energy or water availability. The transition between water- and energy-limited regimes is related to soil moisture and is often characterized as a threshold, denoted as critical soil moisture threshold (θcrit). However, the determination of θcrit is subject to uncertainties due to the different methods used to evaluate the relationship between ETa and soil moisture (SM), such as SM depths, definitions of ETa and curve fitting functions. Typically, surface SM is used to identify θcrit as it is easily accessible and assumed to represent root zone SM status. Weighable lysimeter technology provides a unique opportunity to assess the role of root zone SM on the transition between water and energy limited ETa. It is widely regarded as the gold standard for measuring in-situ ET, and at the same time allows for in-situ SM measurements at different depths. In this study, we estimated θcrit using in situ SM measurements at 10 cm depth and root zone SM by vertically integrating in situ SM (0–60 cm) observations. In addition, we applied three different definitions of relative evapotranspiration (evaporative fraction, the ratio of ETa to grass reference evapotranspiration and the ratio of actual ETa to calculated potential evapotranspiration) as well as two different fitting curves to investigate the sensitivities of θcrit. We found robust θcrit estimates across different definitions and fitting curve methods, but the estimates were significantly higher for root zone than for surface θcrit. Our results also highlight the high correlation (0.83) between root zone and surface θcrit. However, the relation between both values is not unique since it depends on the actual moisture profile and plant root system and, herewith, on the soil type and previous weather conditions. We further observed that both surface and root zone θcrit decreased with increasing sand fraction. Under changing climatic conditions but with identical soil and ecosystem types, both surface and root zone θcrit decreased with increasing aridity. Additionally, we found that using the midpoint between field capacity and wilting point provides a reliable range of root zone θcrit for a given soil texture
Challenges and opportunities of implementing artificial intelligence in the SME machinery industry : literature review
No full textTekoälyn hyödyntäminen valmistavassa teollisuudessa on viimevuosina kehittynyt nopeasti, mutta pienissä ja keskisuurissa konepajayrityksissä sen käyttöönotto etenee edelleen varovaisesti. Tämän kandidaatintyön tavoitteena oli tarkastella tekoälyn käyttöönottoa pk-konepajayrityksissä tuotannon näkökulmasta. Työssä selvitettiin tekoälyn keskeisiä sovelluskohteita tuotantoprosesseissa, tekoälyn käyttöönoton merkittävimpiä haasteita sekä niiden tekijöitä, jotka edistävät tekoälyn onnistunutta hyödyntämistä pk-yrityksissä. Tutkimus toteutettiin kirjallisuuskatsauksena, jossa hyödynnettiin ajankohtaisia tieteellisiä artikkeleita sekä pk-yrityksiin ja valmistavaan teollisuuteen kohdistuvia tutkimuksia.
Tulosten perusteella tekoäly tarjoaa pk-konepajoille merkittäviä mahdollisuuksia tuotannon kehittämiseen, laadun parantamiseen ja päätöksenteon tukemiseen. Keskeisiä sovelluskohteita ovat ennakoiva kunnossapito, tuotannon suunnittelu ja aikataulutus, laadunvalvonta sekä toimitusketjun ja materiaalivirtojen optimointi. Näiden sovellusten avulla pk-yritykset voivat vähentää seisokkeja, parantaa resurssien käyttöä ja pienentää hukkakustannuksia ilman laajamittaisia tuotantojärjestelmien uudistuksia.
Tekoälyn käyttöönottoa pk-konepajoissa hidastavat kuitenkin useat toisiinsa kytkeytyvät haasteet. Keskeisimpiä esteitä ovat taloudellisten resurssien rajallisuus, puutteellinen data ja järjestelmien integraatio, osaamisvaje sekä organisatoriset ja kulttuuriset tekijät. Onnistunut käyttöönotto edellyttää selkeää strategista suuntaa, johdon sitoutumista, henkilöstön osaamisen kehittämistä sekä vaiheittaista ja realistista etenemistä. Työ osoittaa, että tekoäly voi toimia pk-konepajoille merkittävänä kilpailukykyä vahvistavana teknologiana, mikäli sen käyttöönotto sovitetaan yritysten todellisiin tarpeisiin ja toimintaympäristöön
Integrating sustainability assessments to facilitate decision making in sustainable water management in agriculture
No full textAbstract
Agricultural production necessitates sustainable practices to ensure long-term and sustained food security. Water is a key ingredient for food production. Ensuring sustainable water management in agriculture is thus essential for global wellbeing. But how do we make sure that our practices are sustainable? A large variety of sustainability assessments abound. Their results may even show conflicting results. In this study, we demonstrate the application of three sustainability assessment methods – Water Footprint Assessment, Cost-Benefit Analysis and Life Cycle Assessment – for the use of a water retainer product on different soil types, crops and growing seasons in a farm in Poland. In addition, we aggregate the results of these assessments through a Multi-Criteria Decision Analysis (PROMETHEE) to facilitate decision making. Our findings suggest that yields of all crops, on all soils in both growing seasons increased. However, yield gain was insufficient in most cases to offset the increased costs of using the water retainer product. The Multi-Criteria Decision Analysis showed that soil type and crops used had a larger effect on rank than the application of the water retainer. Overall, the conclusion from the various methods is to not recommend the use of the water retainer as an efficient water saving technology for the specific case. Our analysis showed the effects on the economic and environmental dimension of sustainability but does not include the social dimension due to the lack of data, leaving an incomplete picture of sustainability.Abstract
Agricultural production necessitates sustainable practices to ensure long-term and sustained food security. Water is a key ingredient for food production. Ensuring sustainable water management in agriculture is thus essential for global wellbeing. But how do we make sure that our practices are sustainable? A large variety of sustainability assessments abound. Their results may even show conflicting results. In this study, we demonstrate the application of three sustainability assessment methods – Water Footprint Assessment, Cost-Benefit Analysis and Life Cycle Assessment – for the use of a water retainer product on different soil types, crops and growing seasons in a farm in Poland. In addition, we aggregate the results of these assessments through a Multi-Criteria Decision Analysis (PROMETHEE) to facilitate decision making. Our findings suggest that yields of all crops, on all soils in both growing seasons increased. However, yield gain was insufficient in most cases to offset the increased costs of using the water retainer product. The Multi-Criteria Decision Analysis showed that soil type and crops used had a larger effect on rank than the application of the water retainer. Overall, the conclusion from the various methods is to not recommend the use of the water retainer as an efficient water saving technology for the specific case. Our analysis showed the effects on the economic and environmental dimension of sustainability but does not include the social dimension due to the lack of data, leaving an incomplete picture of sustainability
”There was no room for emotions, yet they rolled over me like a tidal wave” : the representation of affects and emotions in autobiography of Janne Raninen They Call Me a Hitman
No full textProperties of Fe-bearing Mg silicate glasses as novel supplementary cementitious materials
No full textAbstract
Blended cements incorporating supplementary cementitious materials (SCMs) offer a viable strategy for reducing the carbon footprint of Portland cement. As traditional SCMs (e.g., blast furnace slags, coal fly ash) become increasingly scarce, the development of alternative materials is crucial. This study evaluates synthetic Fe-bearing Mg silicate glasses as potential low-carbon SCMs, free from direct CO2 emissions associated with raw material processing. Three types of synthetic glasses (Mg-Si, Fe3+-Mg-Si, and Fe2+/Fe3+-Mg-Si glasses) were assessed for their pozzolanic activity and used to replace 20 wt% of Portland cement. Mortar samples incorporating these glasses demonstrated a strength activity index increase of up to 120% compared to the control. Microstructural analysis revealed enhanced formation of C-(A-)S-H and Fe-bearing Mg-containing phases, including Mg-Al(Fe) layered double hydroxides (LDHs). The incorporation of Fe was observed to promote Al mobilization, facilitating early sulfate reactions and potentially influencing cement hydration kinetics. This work shows how non-conventional glass-based SCMs can be engineered to enhance blended cement performance while lowering carbon emissions.Abstract
Blended cements incorporating supplementary cementitious materials (SCMs) offer a viable strategy for reducing the carbon footprint of Portland cement. As traditional SCMs (e.g., blast furnace slags, coal fly ash) become increasingly scarce, the development of alternative materials is crucial. This study evaluates synthetic Fe-bearing Mg silicate glasses as potential low-carbon SCMs, free from direct CO2 emissions associated with raw material processing. Three types of synthetic glasses (Mg-Si, Fe3+-Mg-Si, and Fe2+/Fe3+-Mg-Si glasses) were assessed for their pozzolanic activity and used to replace 20 wt% of Portland cement. Mortar samples incorporating these glasses demonstrated a strength activity index increase of up to 120% compared to the control. Microstructural analysis revealed enhanced formation of C-(A-)S-H and Fe-bearing Mg-containing phases, including Mg-Al(Fe) layered double hydroxides (LDHs). The incorporation of Fe was observed to promote Al mobilization, facilitating early sulfate reactions and potentially influencing cement hydration kinetics. This work shows how non-conventional glass-based SCMs can be engineered to enhance blended cement performance while lowering carbon emissions
Solvent-Mediated Dewetting Principles for Cell-Sized Liposome Formation
No full textAbstract
Reconstitution of synthetic cells holds potential to advance synthetic biology, biomanufacturing, and therapeutics. Microfluidic generation of cell-sized liposomes via double emulsion templating offers precise control over composition and formation process, yet the principles underlying solvent-mediated dewetting remain poorly understood. Using a solvent combination of hexanol and paraffin oil, we demonstrate that solvent-mediated dewetting liposome generation entails both solvent removal and the application of mechanical stimuli. Solvent removal suffices to induce the morphological transition from double emulsions to partially dewetted liposomes exhibiting low and high budding angles of the residual oil pockets. This transition is driven by relaxation of monolayer and membrane tensions, arising from the increased lipid packing density at the liposome interfaces during solvent depletion. While dewetting kinetics and intermediate stages are governed by solvent removal rate, complete dewetting is not spontaneous. Using optical tweezers, we identify tethering between the liposome and oil pocket and characterize the mechanical force required for liposome detachment. By integrating these principles, a predictive, high-throughput approach for generating biocompatible, surfactant-free liposomes is provided. These findings establish a mechanistic framework for liposome dewetting and, through similarities to lipid droplet morphogenesis, offer a protocell platform that could further the understanding of biological budding processes.Abstract
Reconstitution of synthetic cells holds potential to advance synthetic biology, biomanufacturing, and therapeutics. Microfluidic generation of cell-sized liposomes via double emulsion templating offers precise control over composition and formation process, yet the principles underlying solvent-mediated dewetting remain poorly understood. Using a solvent combination of hexanol and paraffin oil, we demonstrate that solvent-mediated dewetting liposome generation entails both solvent removal and the application of mechanical stimuli. Solvent removal suffices to induce the morphological transition from double emulsions to partially dewetted liposomes exhibiting low and high budding angles of the residual oil pockets. This transition is driven by relaxation of monolayer and membrane tensions, arising from the increased lipid packing density at the liposome interfaces during solvent depletion. While dewetting kinetics and intermediate stages are governed by solvent removal rate, complete dewetting is not spontaneous. Using optical tweezers, we identify tethering between the liposome and oil pocket and characterize the mechanical force required for liposome detachment. By integrating these principles, a predictive, high-throughput approach for generating biocompatible, surfactant-free liposomes is provided. These findings establish a mechanistic framework for liposome dewetting and, through similarities to lipid droplet morphogenesis, offer a protocell platform that could further the understanding of biological budding processes
Prevalence and determinants of time to first intimate partner violence incidents among ever-married Ethiopian women
No full textAbstract
Background:
Intimate partner violence (IPV), including physical, emotional, and sexual abuse disproportionately affects women globally, particularly in sub-Saharan Africa.
Objective:
This study examined the timing and determinants of first experiences of IPV among ever-married Ethiopian women.
Participants and setting:
The study analyzed nationally representative data from 4720 ever-married women who participated in the 2016 Ethiopian Demographic and Health Survey.
Methods:
Cox proportional hazards and parametric accelerated failure time (AFT) models were used to identify factors influencing time to first IPV. Women who had not experienced IPV by the survey date or who reported IPV occurring before marriage were treated as right-censored. Multiple AFT distributions were compared, and the best-fitting models were selected.
Results:
Approximately 30 % of women reported experiencing at least one form IPV, most commonly emotional (22.3 %). The log-normal AFT model best fit physical and sexual violence, while the Weibull AFT model fit emotional violence. Older women (35–49 years) experienced IPV later than younger women (time ratios [TR]: 2.09 physical, 2.82 sexual, 3.00 emotional). Husband's alcohol use, controlling behavior, family violence history, and fear of the husband were associated with earlier IPV occurrence (TR 1), while older age at marriage predicted earlier emotional violence (TR = 0.7).
Conclusions:
Age, regional differences, family background, and husbands' behaviors significantly influence the timing of IPV onset among Ethiopian women. Targeted prevention programs addressing harmful partner behaviors, alcohol use, and intergenerational violence are essential to delay or prevent IPV and safeguard women's wellbeing.Abstract
Background:
Intimate partner violence (IPV), including physical, emotional, and sexual abuse disproportionately affects women globally, particularly in sub-Saharan Africa.
Objective:
This study examined the timing and determinants of first experiences of IPV among ever-married Ethiopian women.
Participants and setting:
The study analyzed nationally representative data from 4720 ever-married women who participated in the 2016 Ethiopian Demographic and Health Survey.
Methods:
Cox proportional hazards and parametric accelerated failure time (AFT) models were used to identify factors influencing time to first IPV. Women who had not experienced IPV by the survey date or who reported IPV occurring before marriage were treated as right-censored. Multiple AFT distributions were compared, and the best-fitting models were selected.
Results:
Approximately 30 % of women reported experiencing at least one form IPV, most commonly emotional (22.3 %). The log-normal AFT model best fit physical and sexual violence, while the Weibull AFT model fit emotional violence. Older women (35–49 years) experienced IPV later than younger women (time ratios [TR]: 2.09 physical, 2.82 sexual, 3.00 emotional). Husband's alcohol use, controlling behavior, family violence history, and fear of the husband were associated with earlier IPV occurrence (TR 1), while older age at marriage predicted earlier emotional violence (TR = 0.7).
Conclusions:
Age, regional differences, family background, and husbands' behaviors significantly influence the timing of IPV onset among Ethiopian women. Targeted prevention programs addressing harmful partner behaviors, alcohol use, and intergenerational violence are essential to delay or prevent IPV and safeguard women's wellbeing
Ionosphere-Thermosphere Coupling in the Northern Polar Region During the May 2024 Geomagnetic Superstorm
No full textAbstract
The May 2024 superstorm, as the most intense geomagnetic storm since 2003, caused a variety of disturbances in the magnetosphere-ionosphere-thermosphere system. This study investigates the long-lasting electron density depletion in the polar region and the underlying ionosphere-thermosphere coupling, based on a comprehensive set of observations from ground and space. Initially, a significant amount of solar wind energy was dissipated at high latitudes, and we estimate that the hemispheric Joule heating reached 1.25 TW by using a newly developed method that utilizes SuperDARN, SuperMAG, and AMPERE data. This intense heating increased the ion temperature by 500–1,200 K in the polar region, as detected by the EISCAT Svalbard radar (ESR). Furthermore, Joule heating caused significant upwelling of the polar thermosphere, evidenced by 300%–480% increase in neutral mass density and a substantial depletion in ΣO/ N2 up to 50%, as observed by several low-Earth-orbit satellites. Both the increase in ion temperature and the change in neutral composition are crucial factors in accelerating the F-region recombination process. Consequently, the transition altitude of molecular to oxygen ions increased dramatically from 200 to 380 km, as detected by the ESR radar. The ultimate consequence was a severe depletion in electron density in the polar F–region ionosphere, reaching 70%–85% on 11 May, which gradually recovered over the next two days. Our analysis underscores the importance of simultaneous, multi-instrument observations for a comprehensive understanding of the coupling chain during extreme geomagnetic disturbances.Abstract
The May 2024 superstorm, as the most intense geomagnetic storm since 2003, caused a variety of disturbances in the magnetosphere-ionosphere-thermosphere system. This study investigates the long-lasting electron density depletion in the polar region and the underlying ionosphere-thermosphere coupling, based on a comprehensive set of observations from ground and space. Initially, a significant amount of solar wind energy was dissipated at high latitudes, and we estimate that the hemispheric Joule heating reached 1.25 TW by using a newly developed method that utilizes SuperDARN, SuperMAG, and AMPERE data. This intense heating increased the ion temperature by 500–1,200 K in the polar region, as detected by the EISCAT Svalbard radar (ESR). Furthermore, Joule heating caused significant upwelling of the polar thermosphere, evidenced by 300%–480% increase in neutral mass density and a substantial depletion in ΣO/ N2 up to 50%, as observed by several low-Earth-orbit satellites. Both the increase in ion temperature and the change in neutral composition are crucial factors in accelerating the F-region recombination process. Consequently, the transition altitude of molecular to oxygen ions increased dramatically from 200 to 380 km, as detected by the ESR radar. The ultimate consequence was a severe depletion in electron density in the polar F–region ionosphere, reaching 70%–85% on 11 May, which gradually recovered over the next two days. Our analysis underscores the importance of simultaneous, multi-instrument observations for a comprehensive understanding of the coupling chain during extreme geomagnetic disturbances
SheafAlign: A Sheaf-theoretic Framework for Decentralized Multimodal Alignment
No full textAbstract
Conventional multimodal alignment methods assume mutual redundancy across all modalities, an assumption that fails in real-world distributed scenarios. We propose SheafAlign, a sheaf-theoretic framework for decentralized multimodal alignment that replaces single-space alignment with multiple comparison spaces. This approach models pairwise modality relations through sheaf structures and leverages decentralized contrastive learning-based objectives for training. SheafAlign overcomes the limitations of prior methods by not requiring mutual redundancy among all modalities, preserving both shared and unique information. Experiments on multimodal sensing datasets show superior zero-shot generalization, cross-modal alignment, and robustness to missing modalities, with 34% lower communication cost than state-of-the-art baselines.Abstract
Conventional multimodal alignment methods assume mutual redundancy across all modalities, an assumption that fails in real-world distributed scenarios. We propose SheafAlign, a sheaf-theoretic framework for decentralized multimodal alignment that replaces single-space alignment with multiple comparison spaces. This approach models pairwise modality relations through sheaf structures and leverages decentralized contrastive learning-based objectives for training. SheafAlign overcomes the limitations of prior methods by not requiring mutual redundancy among all modalities, preserving both shared and unique information. Experiments on multimodal sensing datasets show superior zero-shot generalization, cross-modal alignment, and robustness to missing modalities, with 34% lower communication cost than state-of-the-art baselines