Integrating Economic and Ecological Benchmarking for a Sustainable Development of Hydropower

Hydropower reservoirs play an increasingly important role for the global electricity supply. Reservoirs are anthropogenically-dominated ecosystems because hydropower operations induce artificial water level fluctuations (WLF) that exceed natural fluctuations in frequency and amplitude. These WLF have detrimental ecological effects, which can be quantified as losses to ecosystem primary production due to lake bottoms that fall dry. To allow for a sustainable development of hydropower, these “ecological costs” of WLF need to be weighed against the “economic benefits” of hydropower that can balance and store intermittent renewable energy. We designed an economic hydropower operation model to derive WLF in large and small reservoirs for three different future energy market scenarios and quantified the according losses in ecosystem primary production in semi-natural outdoor experiments. Our results show that variations in market conditions affect WLF differently in small and large hydropower reservoirs and that increasing price volatility magnified WLF and reduced primary production. Our model allows an assessment of the trade-off between the objectives of preserving environmental resources and economic development, which lies at the core of emerging sustainability issues

Flow field-induced drag forces and swimming behavior of three benthic fish species

Modern ethohydraulics is the study of the behavioral responses of swimming fish to flow fields. However, the exact drag forces experienced by fish remain poorly studied; this information is required to obtain a better understanding of the behavioral responses of fish and their current resistance strategies. We measured near-ground frontal drag forces on preserved individuals of three benthic fish species, round goby ( Neogobius melanstomus ), gudgeon ( Gobio gobio ) and bullhead ( Cottus gobio ), in a flow channel. The forces were compared to acoustic Doppler velocity (ADV) measurements and fish tracking data based on video observations of live fish in the flow channel. Overall, we observed drag coefficients (C D ) of ∼10 −3 at Reynolds numbers ∼10 5 . The frontal drag forces acting on preserved fish with non-spread fins ranged from -1.96 mN*g -1 (force per fish wet weight, velocity 0.55 m*s -1 ) to 11.01 mN*g -1 (velocity 0.85 m*s -1 ). Spreading the fins strongly increased the drag forces for bullhead and round goby. In contrast, the drag forces were similar for gudgeon with spread fins and all fish with non-spread fins. Video tracking revealed no clear relationship between the position of the fish in the flow field and the forces experienced by the preserved fish at these positions. Collectively, these results suggest that i) the differences in frontal drag forces between species are small in homogenous flow, ii) individuals chose their position in the flow field based on factors other than the drag forces experienced, and iii) whether fins are spread or non-spread is an essential quality that modulates species-specific differences. The methodology and results of this study will enable integration of flow measurements, fish behavior and force measurements and inform ethohydraulics research. More advanced force measurements will lead to a detailed understanding of the current resistance strategies of benthic fish and improve the design of fish passes

Comparative swimming performance and behaviour of three benthic fish species: The invasive round goby (Neogobius melanostomus), the native bullhead (Cottus gobio), and the native gudgeon (Gobio gobio)

Efforts to restore river ecosystem connectivity focus predominantly on diadromous, economically important fish species, and less attention is given to nonmigratory, small‐bodied, benthic fish species. Data on benthic fish swimming performance and behaviour in comparison with ecologically similar native species are especially relevant for the study of one of the most successful invaders in the last decades: the Ponto‐Caspian gobiid species Neogobius melanostomus. To evaluate future measures against its further upstream dispersal, we conducted comparative swimming performance and behaviour experiments with round goby and two native species: the European bullhead (Cottus gobio) and the gudgeon (Gobio gobio). Experiments in a swim tunnel revealed a high variation in the swimming performance and behaviour within and among the three species. Gudgeon performed best in both U$_{crit}$ and U$_{sprint}$ experiments and displayed a rather continuous, subcarangiform swimming mode, whereas bullhead and round goby displayed a burst‐and‐hold swimming mode. Experiments in a vertical slot pass model, which contained a hydraulic barrier as a challenge to upstream movement, confirmed the high swimming performance of gudgeon. Gudgeon dispersed upstream even across the hydraulic barrier at the highest flow velocities. Round goby showed a higher capability to disperse upstream than bullhead, but failed to pass the hydraulic barrier. Our results on comparative swimming performance and behaviour can inform predictive distribution modelling and range expansion models, and also inform the design of selective barriers to prevent the round goby from dispersing farther upstream

Flow field-induced drag forces and swimming behavior of three benthic fish species

Modern ethohydraulics is the study of the behavioral responses of swimming fish to flow fields. However, the exact drag forces experienced by fish remain poorly studied; this information is required to obtain a better understanding of the behavioral responses of fish and their current resistance strategies. We measured near-ground frontal drag forces on preserved individuals of three benthic fish species, round goby ( Neogobius melanstomus ), gudgeon ( Gobio gobio ) and bullhead ( Cottus gobio ), in a flow channel. The forces were compared to acoustic Doppler velocity (ADV) measurements and fish tracking data based on video observations of live fish in the flow channel. Overall, we observed drag coefficients (C D ) of ∼10 −3 at Reynolds numbers ∼10 5 . The frontal drag forces acting on preserved fish with non-spread fins ranged from -1.96 mN*g -1 (force per fish wet weight, velocity 0.55 m*s -1 ) to 11.01 mN*g -1 (velocity 0.85 m*s -1 ). Spreading the fins strongly increased the drag forces for bullhead and round goby. In contrast, the drag forces were similar for gudgeon with spread fins and all fish with non-spread fins. Video tracking revealed no clear relationship between the position of the fish in the flow field and the forces experienced by the preserved fish at these positions. Collectively, these results suggest that i) the differences in frontal drag forces between species are small in homogenous flow, ii) individuals chose their position in the flow field based on factors other than the drag forces experienced, and iii) whether fins are spread or non-spread is an essential quality that modulates species-specific differences. The methodology and results of this study will enable integration of flow measurements, fish behavior and force measurements and inform ethohydraulics research. More advanced force measurements will lead to a detailed understanding of the current resistance strategies of benthic fish and improve the design of fish passes

Device-independent and semi-device-independent entanglement certification in broadcast Bell scenarios

It has recently been shown that by broadcasting the subsystems of a bipartite quantum state, one can activate Bell nonlocality and significantly improve noise tolerance bounds for device-independent entanglement certification. In this work we strengthen these results and explore new aspects of this phenomenon. First, we prove new results related to the activation of Bell nonlocality. We construct Bell inequalities tailored to the broadcast scenario, and show how broadcasting can lead to even stronger notions of Bell nonlocality activation. In particular, we exploit these ideas to show that bipartite states admitting a local hidden-variable model for general measurements can lead to genuine tripartite nonlocal correlations. We then study device-independent entanglement certification in the broadcast scenario, and show through semidefinite programming techniques that device-independent entanglement certification is possible for the two-qubit Werner state in essentially the entire range of entanglement. Finally, we extend the concept of EPR steering to the broadcast scenario, and present novel examples of activation of the two-qubit isotropic state. Our results pave the way for broadcast-based device-dependent and semi-device-independent protocols.Comment: Updated appendices, 28 pages, 4 figure

Increasing flexibility in teacher education: An analysis of current and prospective students’ perspectives

Ausgehend von der Annahme, dass eine höhere Flexibilität bei der Erfüllung der Studienanforderungen zu mehr Attraktivität der Lehrerinnen- und Lehrerbildung und zu besserer Studierbarkeit beitragen kann, werden in diesem Beitrag Äusserungen von Studieninteressierten und Studierenden zu Flexibilität im Studium explorativ untersucht. Beide Gruppen äussern klare Wünsche nach räumlich-zeitlicher Flexibilität, die es ihnen ermöglicht, Studienanforderungen mit anderen Lebensanforderungen zu vereinbaren. Geringe Flexibilität erzeugt ein Stressempfinden bei Studierenden und stellt für Studieninteressierte eine mögliche Hürde bei der Studienwahl dar. (DIPF/Orig.)Based on the assumption that increased flexibility in the fulfilment of study requirements can enhance the attractiveness and the feasibility of teacher education programmes, this article explores the views of current and prospective students regarding flexibility in study programmes and student life. Both groups express a clear wish for spatial and temporal flexibility, which would allow them to balance academic requirements with other demands of life. A lack of flexibility causes stress among current students and may pose a barrier for prospective students when choosing their study programme. (DIPF/Orig.

Perceived Recovery States and Physical Fitness in Reserve Officers’ Training Corps Cadets

Reserve Officers’ Training Corps (ROTC) cadets are challenged mentally, emotionally, and physically with the physical fitness requirements (e.g., Army Combat Fitness Test or ACFT) required within their military science curriculum. Common physical fitness tests such as those for strength, power, and balance can provide insight into the recovery and readiness status of tactical athletes. PURPOSE: The purpose of this study was to explore the relationship between scores on the Short Recovery and Stress Scale (SRSS) and performance on a physical fitness test battery assessing balance, mobility, body composition, muscular strength, and power in collegiate ROTC cadets. METHODS: Seventeen ROTC cadets (20.1 ± 1.2y, 171.1 ± 11.2cm, 76.7 ± 21.0kg) volunteered to participate in a test battery and complete the eight items on the SRSS during the same week they conducted the ACFT. The test battery included measures of body composition (skinfolds), muscular strength (hand-grip), power (vertical jump), balance (Y-Balance), and mobility (sit and reach test). The SRSS consisted of the short recovery scale (SRS) and the short stress scale (SSS). The SRS contains 4 items on physical (PPC) and mental performance capabilities (MPC), emotional balance and overall stress. The SSS contains 4 items on muscular stress (MS), lack of activation (LA), negative emotional state (NES), and overall stress (OS). Descriptive statistics and correlations were calculated using SPSS version 28 (IBM Corp, Armonk, NY). RESULTS: For the SRS, significant correlations were found between 1) vertical jump power and both PPC (r = 0.59, p = 0.02) and MPC (r = 0.74, p \u3c 0.01), 2) MPC and body composition (r = -0.64, p = 0.01), and 3) PPC and right hand-grip (r = 0.52, p = 0.03). For the SSS, significant correlations were found for 1) vertical jump power and MS (r = -0.59, p = 0.02), LA (r = -0.51, p = 0.04), and OS (r = -0.51, p = 0.04), 2) NES and Y-Balance composite score for the right side of the body (r = 0.57, p = 0.02), and 3) OS and body composition (r = 0.64, p = 0.01). CONCLUSION: Conducting regular physical tests such as hand grip strength or vertical jump to give ROTC cadets feedback on current performance status may help increase awareness of the impact of physical, mental and emotional stress on their readiness for the demanding requirements of the military science curriculum

Perceived Recovery States and Physical Fitness in Reserve Officers’ Training Corps Cadets

Reserve Officers’ Training Corps (ROTC) cadets are challenged mentally, emotionally, and physically with the physical fitness requirements (e.g., Army Combat Fitness Test or ACFT) required within their military science curriculum. Common physical fitness tests such as those for strength, power, and balance can provide insight into the recovery and readiness status of tactical athletes. PURPOSE: The purpose of this study was to explore the relationship between scores on the Short Recovery and Stress Scale (SRSS) and performance on a physical fitness test battery assessing balance, mobility, body composition, muscular strength, and power in collegiate ROTC cadets. METHODS: Seventeen ROTC cadets (20.1 ± 1.2y, 171.1 ± 11.2cm, 76.7 ± 21.0kg) volunteered to participate in a test battery and complete the eight items on the SRSS during the same week they conducted the ACFT. The test battery included measures of body composition (skinfolds), muscular strength (hand grip) and power (countermovement vertical jump), balance (Y-Balance), and mobility (sit and reach test). The SRSS consisted of the short recovery scale (SRS) and the short stress scale (SSS). The SRS contains 4 items on physical (PPC) and mental performance capabilities (MPC), emotional balance and overall stress. The SSS contains 4 items on muscular stress (MS), lack of activation (LA), negative emotional state (NES), and overall stress (OS). Descriptive statistics and correlations were calculated using SPSS version 28 (IBM Corp, Armonk, NY), using an alpha significance level of p \u3c 0.05. RESULTS: For the SRS, significant correlations were found between 1) vertical jump power and both PPC and MPC (r = 0.59 and r = 0.74, respectively), 2) MPC and body composition (r = -0.64), and 3) PPC and right hand-grip (r = 0.52). For the SSS, significant correlations were found for 1) vertical jump power and MS (r = -0.59), LA (r = -0.51), and OS (r = -0.51), 2) NES and Y-Balance composite score for the right side of the body (r = 0.57), and 3) OS and body composition (r = 0.57). CONCLUSION: Conducting regular physical tests such as hand grip strength or vertical jump to give ROTC cadets feedback on current performance status may help increase awareness of the impact of physical, mental, and emotional stress on their readiness for the demanding requirements of the military science curriculum

Vertigo's Musical Gaze: Neo-Riemannian Symmetries and Spirals

Laura Mulvey coined the term ‘male gaze’ (1975), using Lacanian theory as a ‘political weapon’ against the standard mode of viewing in which the viewing subject turns onscreen women into fantasy objects. While politically laudable, her article misconstrues Lacan's concept of ‘the gaze’, the power of which emanates from the object itself. We might better serve Lacanian theory by inverting Mulvey's reading of Alfred Hitchcock's Vertigo to suggest that Scottie (James Stewart) is himself objectified by the mystique of the ‘object’ he watches and follows: Madeleine (Kim Novak). The screen's gaze reduces spectators to objects too. From this perspective, rather than watching the film, the film can be said to be watching us. This extends to Bernard Herrmann's soundtrack, famously influenced by the yearning of Wagner's Tristan und Isolde . Developing David Schwarz's (2006) musical gaze (in which repeated pedal points of Schubert songs gaze at us), I analyse Vertigo ’s frequent emphasis on the pitch class D. A pedal D is often repeated in alluring yet sinister bare octaves as Scottie follows Madeleine. But at key moments in the film, the pitch becomes a sophisticated tool that captivates us in unique ways. Around this central pitch third‐relationships circle. These resonate with neo‐Riemannian theory, particularly in their hexatonic ‘poles’, which Cohn shows to be agents of the Freudian ‘uncanny’ (2004) and which here also serve as an alternative gaze to the reiterated D. Other pitch constellations, in symmetries or spirals, form similar obsessional musical ‘gazes’ that, using Lacanian theory, prompt the question about whether we are listening to the music or the music is listening to us

Lipid and Non-lipid Factors Affecting Macrophage Dysfunction and Inflammation in Atherosclerosis

Atherosclerosis is a chronic inflammatory disease and a leading cause of human mortality. The lesional microenvironment contains a complex accumulation of variably oxidized lipids and cytokines. Infiltrating monocytes become polarized in response to these stimuli, resulting in a broad spectrum of macrophage phenotypes. The extent of lipid loading in macrophages influences their phenotype and consequently their inflammatory status. In response to excess atherogenic ligands, many normal cell processes become aberrant following a loss of homeostasis. This can have a direct impact upon the inflammatory response, and conversely inflammation can lead to cell dysfunction. Clear evidence for this exists in the lysosomes, endoplasmic reticulum and mitochondria of atherosclerotic macrophages, the principal lesional cell type. Furthermore, several intrinsic cell processes become dysregulated under lipidotic conditions. Therapeutic strategies aimed at restoring cell function under disease conditions are an ongoing coveted aim. Macrophages play a central role in promoting lesional inflammation, with plaque progression and stability being directly proportional to macrophage abundance. Understanding how mixtures or individual lipid species regulate macrophage biology is therefore a major area of atherosclerosis research. In this review, we will discuss how the myriad of lipid and lipoprotein classes and products used to model atherogenic, proinflammatory immune responses has facilitated a greater understanding of some of the intricacies of chronic inflammation and cell function. Despite this, lipid oxidation produces a complex mixture of products and with no single or standard method of derivatization, there exists some variation in the reported effects of certain oxidized lipids. Likewise, differences in the methods used to generate macrophages in vitro may also lead to variable responses when apparently identical lipid ligands are used. Consequently, the complexity of reported macrophage phenotypes has implications for our understanding of the metabolic pathways, processes and shifts underpinning their activation and inflammatory status. Using oxidized low density lipoproteins and its oxidized cholesteryl esters and phospholipid constituents to stimulate macrophage has been hugely valuable, however there is now an argument that only working with low complexity lipid species can deliver the most useful information to guide therapies aimed at controlling atherosclerosis and cardiovascular complications