A renewable power system for an off-grid sustainable telescope fueled by solar power, batteries and green hydrogen

A large portion of astronomy's carbon footprint stems from fossil fuels supplying the power demand of astronomical observatories. Here, we explore various isolated low-carbon power system setups for the newly planned Atacama Large Aperture Submillimeter Telescope, and compare them to a business-as-usual diesel power generated system. Technologies included in the designed systems are photovoltaics, concentrated solar power, diesel generators, batteries, and hydrogen storage. We adapt the electricity system optimization model highRES to this case study and feed it with the telescope's projected energy demand, cost assumptions for the year 2030 and site-specific capacity factors. Our results show that the lowest-cost system with LCOEs of $116/MWh majorly uses photovoltaics paired with batteries and fuel cells running on imported and on-site produced green hydrogen. Some diesel generators run for backup. This solution would reduce the telescope's power-side carbon footprint by 95% compared to the business-as-usual case.Comment: 16 pages, 10 figure

Editorial for the special issue “characterization of nanomaterials: Selected papers from 6th dresden nanoanalysis symposium”

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Tailoring the properties of a-site substituted Ba1-xGd0.8La0.2+xCo2O6-δ

The double perovskite BaGd0.8La0.2Co2O6-δ (BGLC) shows excellent performance as oxygen electrode for Proton Ceramic Fuel Cells (PCFCs) and electrolyzer cells (PCEC), with polarization resistances in wet oxygen of 0.04 and 10 Ωcm2 at 650 and 350 ⁰C, respectively [1]. Compared with other reported PCFC cathodes [2], BGLC performs better both at high and low temperature. The excellent performance of BGLC in proton ceramic cells is rationalized by a suggested partial proton conductivity at intermediate temperatures, supported by significant hydration up to 400°C observed by thermogravimetric studies. However, the chemical stability of BGLC in high steam pressures under PCEC operation remains a concern due to its highly basic A-site. Thus, tailoring the A-site stoichiometry by partial substitution of Ba with La may be a viable route for further optimizing the balance between chemical stability and electrochemical performance. In the literature we find numerous defect chemical models describing REBaCo2O5.5+δ-type double perovskites, but these are typically limited to describing the oxygen non-stoichiometry. Little can be found which relates defect chemistry to electrochemical performance, electrical conductivity or hydration behavior. Thus, this contribution aims to develop a global defect chemical model of the system Ba1‑xGd0.8La0.2+xCo2O6-δ (x = 0-0.5) by investigating its structural and functional properties as a function of Ba-site substitution. The complex structural behavior of Ba-site substituted BGLC is elucidated by combining synchrotron and neutron diffraction data with high temperature XRD to describe the local Co-O environment and the degree of cation and anion ordering as a function of temperature and pO2. The implications of A-site stoichiometry on proton incorporation are further investigated by thermogravimetric hydration studies supported by neutron powder diffraction of dry and deuterated samples. Finally, these properties are linked to oxygen non-stoichiometry, electrical conductivity and electrochemical performance to develop and validate our general defect chemical model for the system Ba1‑xGd0.8La0.2+xCo2O6-δ (x = 0-0.5). Please click Additional Files below to see the full abstract

Simulating offshore hydrogen production via PEM electrolysis using real power production data from a 2.3 MW floating offshore wind turbine

This work presents simulation results from a system where offshore wind power is used to produce hydrogen via electrolysis. Real-world data from a 2.3 MW floating offshore wind turbine and electricity price data from Nord Pool were used as input to a novel electrolyzer model. Data from five 31-day periods were combined with six system designs, and hydrogen production, system efficiency, and production cost were estimated. A comparison of the overall system performance shows that the hydrogen production and cost can vary by up to a factor of three between the cases. This illustrates the uncertainty related to the hydrogen production and profitability of these systems. The highest hydrogen production achieved in a 31-day period was 17 242 kg using a 1.852 MW electrolyzer (i.e., utilization factor of approximately 68%), the lowest hydrogen production cost was 4.53 $/kg H2, and the system efficiency was in the range 56.1–56.9% in all cases.publishedVersio

GH and IGF System: The Regulatory Role of miRNAs and lncRNAs in Cancer

Growth hormone (GH) and the insulin-like growth factor (IGF) system are involved in many biological processes and have growth-promoting actions regulating cell proliferation, differentiation, apoptosis and angiogenesis. A recent chapter in epigenetics is represented by microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) which regulate gene expression. Dysregulated miRNAs and lncRNAs have been associated with several diseases including cancer. Herein we report the most recent findings concerning miRNAs and lncRNAs regulating GH and the IGF system in the context of pituitary adenomas, osteosarcoma and colorectal cancer, shedding light on new possible therapeutic targets. Pituitary adenomas are increasingly common intracranial tumors and somatotroph adenomas determine supra-physiological GH secretion and cause acromegaly. Osteosarcoma is the most frequent bone tumor in children and adolescents and was reported in adults who were treated with GH in childhood. Colorectal cancer is the third cancer in the world and has a higher prevalence in acromegalic patients

Facilitating Sustainable Career Development in Fragility: A Psycho-Linguistic Intervention for Employability of Individuals with Fragile Literacy Skills

The brief report examines the burgeoning interest in sustainable career development by discussing the role of employability of individuals with fragile literacy skills, i.e., second-language learners (L2), and individuals with developmental dyslexia (DD). Considering sustainable career development as the umbrella of practices facilitating individuals flourishing, we aim to present an integrated flexible intervention to promote the employability of individuals with fragile literacy skills (DD and L2) that combines both the promotion of linguistic skills and psychological resources. Using an experimental research design, we tested our training intervention on language skills (reading and writing) coupled with psychological training intended to enhance psychological resources and psychological capital. A total of 38 individuals with DD took part in our examination (n = 22 in the experimental group) and n = 26 L2 (n = 11 in the experimental group). We measured employability skills and psychological capital pre and post our interventions both in the control and in the experimental groups. Our result show that the intervention led to a significant improvement in L2 and DD. We discuss our results and implications for research and practice

Sustainable Astronomy: A comparative Life Cycle Assessment of Off-grid Hybrid Energy Systems to supply large Telescopes

Purpose Supplying off-grid facilities such as astronomical observatories with renewable energy-based systems (RES) instead of diesel generators can considerably reduce their environmental impact. However, RES require oversized capacities to counter intermittency and comply with reliability requirements, hence shifting the environmental impact from operation to construction phase. We assess whether 100% RES scenarios are favorable from an environmental point of view, and discuss the trade-offs in systems with backup fossil generators versus 100% renewable ones. Methods In this comparative life cycle assessment (LCA), we study various RES supply systems to power a new telescope in the Atacama desert, Chile. We compare six setups, including 100% RES scenarios, namely photovoltaics (PV) with batteries and hydrogen energy storage; high-renewable scenarios, with fossil fuel power generation next to RES and storage; and a system combining PV with diesel generation. We base system sizing on a techno-economical optimization for the start of operation in 2030. Foreground data stem from recent life cycle inventories of RES components and 2030 electricity mix assumptions of production places. We assess environmental impact in the categories climate change, mineral resource depletion and water use. Results and discussion We find that 100% RES and high-renewable scenarios result in emissions of 0.077-0.115kg CO2e/kWh supplied, compared to 0.917kg CO2e/kWh in the reference case with solely diesel generation. 100% RES scenarios have a lower CO2e impact than high-renewable scenarios. However, the latter lower the mineral resource depletion and water use by about 27% compared to 100% RES scenarios. Applying hybrid energy storage systems increases the water use impact, while reducing the mineral resource depletion. Conclusions None of the six energy systems we compared was clearly the best in all environmental impacts considered. Trade-offs must be taken when choosing an energy system to supply the prospective off-grid telescope in Chile. We find high-renewable systems with some fossil generation as the better option regarding power reliability, mineral resource depletion and water use, while inducing slightly higher greenhouse gas emissions than the 100% RES scenarios. As remote research facilities and off-grid settlements today are mainly supplied by fossil fuels, we expect to motivate more multifaceted decisions for implementing larger shares of RES for these areas. To advance the LCA community in the field of energy systems, we should strive to incorporate temporal and regional realities into our life cycle inventories. To ease the path for upcoming studies, we publish this work’s inventories as detailed activity level datasets

Operando SAXS/WAXS on the a-P/C as the Anode for Na-Ion Batteries

A complete chemical and morphological analysis of the evolution of battery electrode materials can be achieved combining different and complementary techniques. Operando small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) were combined to investigate structural and electrochemical performances of an Na-ion battery, with amorphous red phosphorus in a carbon matrix (a-P/C) as the active anode material in a Swagelok-type cell. The charging process results in the formation of crystalline Na3P, while during discharging, the anode material returns to the initial a-P/C. From the analysis of the WAXS curves, the formation of crystalline phases appears only at the end of charging. However, SAXS data show that partial reorganization of the material during charging occurs at length scales nonaccessible with conventional X-ray diffraction, corresponding to a real space ordering distance of 4.6 nm. Furthermore, the analysis of the SAXS data shows that the electrode remains dense during charging, while it develops some porosity during the discharge phase. The presented results indicate that the combination of SAXS/WAXS adopted simultaneously, and nondestructively, on a working electrochemical cell can highlight new mechanisms of reactions otherwise undetected. This method can be applied for the study of any other solid electrode material for batteries

Specific miRNAs Change After 3 Months of GH treatment and Contribute to Explain the Growth Response After 12 Months

Context: There is growing evidence of the role of epigenetic regulation of growth, and miRNAs potentially play a role. Objective: The aim of this study is to identify changes in circulating miRNAs following GH treatment in subjects with isolated idiopathic GH deficiency (IIGHD) after the first 3 months of treatment, and verify whether these early changes can predict growth response. Design and methods: The expression profiles of 384 miRNAs were analyzed in serum in 10 prepubertal patients with IIGHD (5 M, 5 F) at two time points before starting GH treatment (t-3, t0), and at 3 months on treatment (t+3). MiRNAs with a fold change (FC) >+1.5 or <-1.5 at t+3 were considered as differentially expressed. In silico analysis of target genes and pathways led to a validation step on 8 miRNAs in 25 patients. Clinical and biochemical parameters were collected at baseline, and at 6 and 12 months. Simple linear regression analysis and multiple stepwise linear regression models were used to explain the growth response. Results: Sixteen miRNAs were upregulated and 2 were downregulated at t+3 months. MiR-199a-5p (p = 0.020), miR-335-5p (p = 0.001), and miR-494-3p (p = 0.026) were confirmed to be upregulated at t+3. Changes were independent of GH peak values at testing, and levels stabilized after 12 months. The predicted growth response at 12 months was considerably improved compared with models using the common clinical and biochemical parameters. Conclusions: MiR-199a-5p, miR-335-5p, and miR-494-3p changed after 3 months of GH treatment and likely reflected both the degree of GH deficiency and the sensitivity to treatment. Furthermore, they were of considerable importance to predict growth response.Context: There is growing evidence of the role of epigenetic regulation of growth, and miRNAs potentially play a role. Objective: The aim of this study is to identify changes in circulating miRNAs following GH treatment in subjects with isolated idiopathic GH deficiency (IIGHD) after the first 3 months of treatment, and verify whether these early changes can predict growth response. Design and methods: The expression profiles of 384 miRNAs were analyzed in serum in 10 prepubertal patients with IIGHD (5 M, 5 F) at two time points before starting GH treatment (t-3, t0), and at 3 months on treatment (t+3). MiRNAs with a fold change (FC) >+1.5 or <-1.5 at t+3 were considered as differentially expressed. In silico analysis of target genes and pathways led to a validation step on 8 miRNAs in 25 patients. Clinical and biochemical parameters were collected at baseline, and at 6 and 12 months. Simple linear regression analysis and multiple stepwise linear regression models were used to explain the growth response. Results: Sixteen miRNAs were upregulated and 2 were downregulated at t+3 months. MiR-199a-5p (p = 0.020), miR-335-5p (p = 0.001), and miR-494-3p (p = 0.026) were confirmed to be upregulated at t+3. Changes were independent of GH peak values at testing, and levels stabilized after 12 months. The predicted growth response at 12 months was considerably improved compared with models using the common clinical and biochemical parameters. Conclusions: MiR-199a-5p, miR-335-5p, and miR-494-3p changed after 3 months of GH treatment and likely reflected both the degree of GH deficiency and the sensitivity to treatment. Furthermore, they were of considerable importance to predict growth response