The accumulation of electrochemically produced bubbles is inevitable in gas-evolving reactions and can induce potential losses by theoretically increasing activation, concentration, and ohmic overpotentials. These effects are often either overstated or completely neglected in the literature, which complicates the accurate analysis of experimental results for gas evolution reactions. This study systematically identifies and quantifies the overpotential losses induced by bubbles by combining experimental results for hydrogen (HER) and oxygen evolution reactions (OER), obtained using the rotating disk electrode (RDE) technique, with simulations based on a two-dimensional transmission line model. Our results show that ohmic overpotential is the primary cause of apparent activity loss due to bubbles in RDE. This effect leads to catalyst activity misestimates exceeding 2 orders of magnitude, and Tafel slope errors of 100% at higher currents if left uncorrected. By identifying these effects, this work provides a robust framework for mitigating inaccuracies and improving the characterization of electrocatalysts for gas evolution reactions.
This summary of the second Terrestrial Very-Long-Baseline Atom Interferometry (TVLBAI) Workshop provides a comprehensive overview of our meeting held in London in April 2024 (Second Terrestrial Very-Long-Baseline Atom Interferometry Workshop, Imperial College, April 2024), building on the initial discussions during the inaugural workshop held at CERN in March 2023 (First Terrestrial Very-Long-Baseline Atom Interferometry Workshop, CERN, March 2023). Like the summary of the first workshop (Abend et al. in AVS Quantum Sci. 6:024701, 2024), this document records a critical milestone for the international atom interferometry community. It documents our concerted efforts to evaluate progress, address emerging challenges, and refine strategic directions for future large-scale atom interferometry projects. Our commitment to collaboration is manifested by the integration of diverse expertise and the coordination of international resources, all aimed at advancing the frontiers of atom interferometry physics and technology, as set out in a Memorandum of Understanding signed by over 50 institutions (Memorandum of Understanding for the Terrestrial Very Long Baseline Atom Interferometer Study).
This article is concerned with qualitative and quantitative refinements of the concepts of the log-convexity and log-concavity of positive sequences. A new class of tempered sequences is introduced, its basic properties are established and several interesting examples are provided. The new class extends the class of log-balanced sequences by including the sequences of similar growth rates, but of the opposite log-behavior. Special attention is paid to the sequences defined by two- and three-term linear recurrences with constant coefficients. For the special cases of generalized Fibonacci and Lucas sequences, we graphically illustrate the domains of their log-convexity and log-concavity. For an application, we establish the concyclicity of the points a2na2n+1,1a2n+1 for some classes of Horadam sequences (an) with positive terms.
Aging residential buildings in urban areas require effective thermal insulation to enhance energy efficiency and indoor comfort. In Bosnia and Herzegovina (BiH), expanded polystyrene (EPS) is the most commonly used insulation material due to its affordability, despite concerns regarding its flammability and environmental impact. While regulatory changes since 2019 have recommended rock wool for high-rise buildings, the absence of binding fire safety regulations has allowed the continued use of EPS, often driven by financial constraints. This study examines energy efficiency refurbishments in Sarajevo’s high-rise residential buildings and analyze the implications of the partial implementation of recommended measures. Using case studies, surveys, and expert interviews, this research identifies key challenges, such as limited funding, fragmented renovations, and inconsistent coordination between stakeholders. The findings indicate that facade insulation is often prioritized over comprehensive upgrades, including window replacement and heating system improvements, leading to suboptimal energy savings and minimal cost reductions for residents. Additionally, the complexity of multi-apartment ownership structures hinders uniform improvements in energy efficiency. Despite these challenges, property values tend to increase after renovation, highlighting the long-term financial benefits. To maximize energy savings and ensure sustainable urban housing, stronger interdisciplinary collaboration, improved funding mechanisms, and adherence to fire-safety standards are necessary. These measures would enhance the effectiveness of renovations and support long-term energy efficiency strategies.
Climate change is predicted to drive geographical range shifts that will result in changes in species diversity and functional composition and have potential repercussions for ecosystem functioning. However, the effect of these changes on species composition and functional diversity (FD) remains unclear, especially for mammals, specifically bats. We used species distribution models and a comprehensive ecological and morphometrical trait database to estimate how projected future climate and land‐use changes could influence the distribution, composition, and FD of the European bat community. Future bat assemblages were predicted to undergo substantial shifts in geographic range and trait structure. Range suitability decreased substantially in southern Europe and increased in northern latitudes. Our findings highlight the potential for climate change to drive shifts in bat FD, which has implications for ecosystem function and resilience at a continental scale. It is important to incorporate FD in conservation strategies. These efforts should target species with key functional traits predicted to be lost and areas expected to experience losses in FD. Conservation strategies should include habitat and roost protection, enhancing landscape connectivity, and international monitoring to preserve bat populations and their ecosystem services.
Human cathelicidin LL‐37 derivative, the 24‐mer SAAP‐148, is highly effective in vitro in eradicating multidrug‐resistant bacteria without inducing resistance. SAAP‐148 has a high cationic charge (+11) and 46% hydrophobicity, which, once the peptide folds into an alpha helix, forms a wide hydrophobic face. This highly amphipathic nature facilitates on the one hand its insertion into the membrane's fatty acyl chain region and on the other hand it´s interaction with anionic membrane components, which aids in killing bacteria. However, the contributions of the secondary and quaternary structures have not been thoroughly investigated so far. To address this, we applied circular dichroism, NMR spectroscopy, X‐ray scattering, AlphaFold 3 protein folding software, and molecular dynamics simulations. Our results reveal that SAAP‐148 adopts a stable hexameric bundle composed of three parallel dimers, that together form a hydrophobic core of aromatic side chain residues. The hexameric structure is retained at the membrane interface, whereby, MD simulation studies indicated the formation of a fiber‐like structure in the presence of anionic membranes. This certainly seems plausible, as oligomers are stabilized by aromatic residues, and the exposure of positively charged side chains on the surface likely facilitates the transition of the peptide into fibrils on anionic membranes.
Background: Undernutrition disorder is a prevalent comorbidity (up to 25%) in type 2 diabetes (T2D) patients which significantly compromises their health. We aimed to assess the association between single nucleotide polymorphysms (SNPs) adiponectin (ADIPOQ) +276 (G/T) and resistin (RETN) −420 (C/G) with the risk of developing T2D and undernutrition in patients with T2D. Methods: The research was conducted as prospective case-control study among 106 patients with T2D and 106 healthy control individuals in the territory of the Bosnia and Herzegovina from Sep 1st 2022 to May 1st 2023. For assessing the nutritional status, the mini nutritional assessment (MNA) was used. DNA analysis was carried out by restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) method. The data were analyzed using chi-square test, t-test for independent samples and binary multivariate logistic regression. Results: The research included 212 subjects of which 124 (58.5%) were male. The mean age of the subjects was 68.48±4,67 yr. Almost 20% of subjects were undernourished, significantly more T2D patients when compared to controls (33% vs. 6.6%; P<0.001). ADIPOQ +276 GT genotype was identified as significant predictor of T2D (OR: 3.454; 95% CI: 1.400–8.521; P=0.007) and undernutrition disorder (OR: 3.453; 95% CI: 1.331–8.961; P=0.011) in T2D population, while the presence of RETN −420 CG genotype had protective effect against occurrence of T2D (OR: 0.353; 95% CI: 0.144–0.867; P=0.023). However, RETN genotypes were not associated with undernutrition disorder. Conclusion: ADIPOQ +276 gene polymorphism represent a significant predictor for development of T2D and undernutrition disorder in T2D population, while RETN −420 gene polymorphism was identified as a significant factor associated with a reduced risk for T2D, but was not associated with undernutrition.
Background: The main feature of osteoarthritis (OA) is the deterioration of articular cartilage, but numerous studies have demonstrated the role of synovial inflammation in the early stages of the disease, leading to further progression of OA. The WNT signaling pathway is involved in numerous activities in joint tissue, but there is a lack of evidence considering the role of WNT in OA synovitis. Our research aims to investigate the expression of WNT Family Member 5A/B (WNT5A/B), β-catenin, acetyl-α-tubulin, Dishevelled-1 (DVL-1), and Inversin (INV) in the synovial membrane of osteoarthritis (OA) hips. Methods: The immunohistochemical expressions of the aforementioned proteins in the synovial membrane were analyzed and compared with samples of control group participants with fractured femoral necks. Results: The immunoexpression of acetyl-α-tubulin was significantly increased in the intima (p < 0.0001) and subintima (p < 0.0001) of the group with OA compared with the intima and subintima of the control group. At the same time, acetyl-α-tubulin was also more highly expressed in the intima of the OA group than in the subintima of the OA group (p < 0.05); we found the same expression pattern in the control group (p < 0.0001). The differential analysis of the GEO dataset did not show significant differences between the osteoarthritis (OA) and control groups in the expression of TUBA1A. β-catenin was significantly increased in the subintima (p < 0.01) of the group with OA compared to the subintima of the control group. WNT expression has significantly higher positivity in the subintima than in the intima, especially in the control group (p < 0.01). WNT5A and WNT5B were significantly down-regulated in OA compared to the control in the differential analysis of the GEO dataset. The expression of INV and DVL-1 in our study and the differential analysis of the GEO dataset did not differ significantly between the osteoarthritis (OA) and control groups. Conclusions: Based on our results, we suggest that acetyl-α-tubulin and β-catenin might be involved in synovial membrane inflammation in OA and serve as potential therapeutic targets.
Background: Different dietary components can affect hematological and biochemical profiles, potentially causing pathohistological changes in liver and kidney tissue. Aim: The animals in the experiment consumed various bakery and meat products, and ultimately, the potential effects on hematological, biochemical, and pathological parameters were evaluated. Methods: The study involved 24 clinically healthy adult rats, randomized into three groups of eight rats each, as follows: rats that consumed meat products (group M), rats that consumed bakery products (group H), and a control group that consumed conventional rodent food (group K) for 7 weeks. After 7 weeks, hematological and biochemical blood analyses were conducted along with pathohistological examinations of the liver and kidneys. Results: Significant differences (p < 0.05) were observed among groups for several hematological and biochemical parameters, including creatinine (CREA), urea, blood urea nitrogen /CREA, calcium, alanine transaminase, alkaline phosphatase, and lipase. Consuming meat products had a less favorable impact on the occurrence of kidney function disorders. Group H exhibited significant differences in leukocyte and platelet counts compared with groups M and K. Extreme echinocytosis was recorded in group M, whereas sideropenic anemia was prominent in group H. Analysis of the livers of rats in groups K and H did not show significant differences in the observed parameters (gamma-glutamyl transferase and total bilirubin), whereas group M had a significantly higher degree of hepatocyte degeneration and steatosis, and the observed infiltrate was also more pronounced, but not significantly. The kidneys of group M showed discrete alterations of the microstructure, i.e., slightly increased cellularity of renal corpuscles and hypertrophy of proximal nephrocyte, whereas the kidney tissue of group K had a regular appearance. Conclusion: Consuming meat products was associated with adverse liver and kidney changes, whereas bakery products led to sideropenic anemia and altered hematological values.
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