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Benchmarking energy efficiency in vertical farming: Status and prospects
No full textEnergy efficiency is a critical yet challenging key performance indicator for vertical farming. The absence of a representative benchmark has thus far hindered comparison with traditional agricultural techniques. This paper aims to establish the current status and future prospects of energy efficiency in vertical farming by exploring the interplay between plant physiology and facility design and operation. Energy use is primarily driven by the need to control the physical environment for crop productivity and quality, resulting in specific lighting and climate control requirements. While artificial lighting technologies are advancing towards the current biological limits of photosynthesis, climate control is increasingly influenced by plant physiological activity. An analysis of studies focusing on energy use in vertical farming reveals a current specific energy consumption of 10–18 kWh kg−1 for lettuce production, corresponding to an energy use intensity of 850–1150 kWh m−2 year−1. Consideration of theoretical crop energy requirements, together with expected advances in equipment efficiency and operational control strategies, suggests a technical energy benchmark of 3.1–7.4 kWh kg−1. Despite projected gains in energy efficiency, the current economic costs and environmental impacts associated with increased electricity use highlight significant challenges to the short-term energy sustainability of vertical farming
Transforming achiral semiconductors into chiral domains with exceptional circular dichroism
No full text: Highly concentrated solutions of asymmetric semiconductor magic-sized clusters (MSCs) of cadmium sulfide, cadmium selenide, and cadmium telluride were directed through a controlled drying meniscus front, resulting in the formation of chiral MSC assemblies. This process aligned their transition dipole moments and produced chiroptic films with exceptionally strong circular dichroism. G-factors reached magnitudes as high as 1.30 for drop-cast films and 1.06 for patterned films, approaching theoretical limits. By controlling the evaporation geometry, various domain shapes and sizes were achieved, with homochiral domains exceeding 6 square millimeters that transition smoothly between left- and right-handed chirality. Our results uncovered fundamental relationships between meniscus deposition processes, the alignment of supramolecular filaments and their MSC constituents, and their connection to emergent chiral properties
How reliable is the evaluation of DNA binding constants? Insights and best practices based on an inter-laboratory fluorescence titration study
No full textIn all experimental sciences, the precision and reliability of quantitative measurements are paramount. This is particularly true when examining the interactions between small molecules and biomolecules/polyelectrolytes, such as DNAs/RNAs, and yet it is overlooked in most publications of thermodynamic binding parameters. This paper presents findings from COST Action 18202 "Network for Equilibria and Chemical Thermodynamics Advanced Research," which assessed the consistency of data derived from the interactions of calf-thymus DNA (CT-DNA) with the fluorescent intercalator ethidium bromide (EB) through spectrofluorimetric titrations. We first discuss critical experimental aspects and propose a reference experimental protocol which can be used to calibrate procedures for the determination of nucleic acid binding equilibrium constants. We then fit the experimental point according to different procedures and analyse the results focusing on the statistical dispersion of the data, aiming at enlightening the strong and weak points of different fitting procedures. The implications of this work are significant, demonstrating how the statistical dispersion of experimental data can influence the interpretation of biochemical coordination mechanisms. Our study reveals that, despite rigorous protocol standardization, the determination of binding parameters remains sensitive to the choice of data fitting method, with deviations in the logarithmic stability constant (logK) values not falling below 5% relative standard deviation (RSD), or ±0.5 logK units for 95% confidence. This variability evidences the critical need for standardized best practices in data treatment as well as experimental procedures. Although our study focuses on the EB/CT-DNA system through fluorescence titrations, the broader implications for other methodologies across various biochemical systems highlight the importance of this first-of-its-kind inter-laboratory comparison in advancing our understanding of biochemical coordination processes
Algorithmic Drift: A simulation framework to study the effects of recommender systems on user preferences
No full textUser navigation on social media platforms is often driven by recommendation algorithms. A growing body of literature questions whether these recommendation systems may exacerbate detrimental phenomena, perpetrate intrinsic biases, and alter user preferences in the long-term. Driven by this premise, the present study formalizes the concept of “algorithmic drift”, further introducing a novel framework and two metrics to quantify it. Our methodology involves a simulation process that models user behavior through random walks, reflecting user navigation under the influence and guidance of recommendation systems. This approach highlights that each user may respond differently to such stimuli, varying in both resistance to recommendation influence and inertia in selecting new steps in the random walk. The proposed metrics measure the drift in user behavior and item consumption over time in the random walks. We conduct a comprehensive evaluation over both synthetic and real-world datasets to validate the framework's ability to measure drift across different parameter settings. All code and data used in our experimentation are publicly accessible online.
An Aurignacian Assemblage from the Island of Lemnos (Greece): Some Aspects of the Beginning of the Upper Paleolithic in the Northeast Aegean
No full textThe discovery of an Aurignacian lithic assemblage along the northern coast of the Island of Lemnos in the northeastern Aegean Sea has opened new perspectives on the study of the beginning of the Upper Paleolithic in this region. The site is located some 93 m from the present seashore. It was discovered in the summer of 2020, ca. 2 km west of the Pournias Bay. The lithics were exposed in a well-defined oval concentration, ca. 25 × 10 m wide, buried by a Holocene sand dune. They were uncovered following sand removal by a bulldozer for the construction of a parking lot. The knapped stones are made almost exclusively from hydrothermal siliceous rocks, a raw material available on the island. Raman spectroscopy and optical observations confirmed that this raw material is chalcedony. The surfaces of most artefacts are weathered due to deposition in
an environment rich in marine salt, which does not preserve any organic material suitable for radiocarbon dating. The knapped stone assemblage consists of diagnostic artefacts, among which are different types of carinated end scrapers, cores, and a few bladelets. The discovery of an Aurignacian site plays an important role in the study of the Paleolithic peopling of Lemnos and the Northeast Aegean in general, a period that was previously
known only through Epipaleolithic sites discovered and excavated mainly along the eastern coast of the island
Suppellettile in vetro e faïence dalla necropoli romana di Antinoupolis
No full textThis paper will focus on glass and faïence finds discovered in the North Roman Necropolis at Antinoupolis. All the materials were found during the excavations carried out from 2012 to 2014 by the mission of the Istituto Papirologico “G. Vitelli” (University of Florence) directed by Rosario Pintaudi. Glass and faïence findings come from a multi-chambered funerary complex intended to accommodate multiple burials. The group of faïence artifacts is outstanding in its richness and variety and includes figurines of a standing god Bes with a flat back, a very interesting inkwell and some plaques with wdjat eye. The glass assemblage consists mainly of free-blown vessels belonging to different forms, mostly bowls, beakers and toilet bottles; of special interest are some candlestick-type bottles and small mould-blown flasks used for the conservation of perfumes and medical substances. All the materials date to the 2nd and 3rd centuries AD
Atherectomy-assisted endovascular therapy versus open repair for atherosclerotic common femoral artery disease: The multicenter ARISTON study
No full textBackground: Endarterectomy (open repair) represents the gold-standard for common femoral atherosclerotic disease (CFAD) treatment. However, with developments like atherectomy, endovascular therapy (endovascular revascularization) may offer an alternative option. The aim of the present study was to evaluate the safety and effectiveness of endovascular versus open therapy for the CFAD. Methods: The ARISTON (AtheRectomy-assIsted endovaScular Therapy versus OpeN) study was an 11-center research collaborative in which data from consecutive patients with symptomatic CFAD were analyzed. Retrospective matching was performed for patient-specific characteristics, including age, cardiovascular risk factors and comorbidities, and lesion-specific variables, including lesion calcification and complexity. Primary endpoints were all-cause mortality and freedom from clinically driven target lesion revascularization (CD-TLR). Amputation-free survival (AFS) was a secondary endpoint. Results: From 2015 to 2022, 826 patients undergoing endovascular (n = 213 [25.8%]) versus open therapy (n = 613 [74.2%]) were analyzed. The total number of procedural complications was higher with open therapy, whereas hospital stay was shorter with endovascular therapy (p < 0.0001 for both). Major adverse cardiac and limb events at 30-day outcomes were, however, not statistically different (p = 0.06). Bail-out stent rates with atherectomy-assisted endovascular therapy were 5.1%. After matching and during 1.72 (0.9–3.3) years of follow up, all-cause mortality, AFS, and CD-TLR were not statistically different in endovascular versus open therapy (HR = 0.68, 95% CI 0.36–1.29; HR = 1.5, 95% CI 0.59–3.77; and HR = 1.46, 95% CI 0.61–3.49, p = NS for all). Conclusion: Endovascular and open therapy exhibit comparable outcomes for the treatment of patients with symptomatic CFAD, including similar CD-TLR in patients with claudication and AFS in patients with chronic limb-threatening ischemia, during short-term follow up. Atherectomy-assisted endovascular therapy may therefore provide a useful alternative for patients who are unfit for surgery
