Hasil untuk "math-ph"

Iván Jares Salguero, Juan José del Campo Gorostidi, Guillermo Laine Cuervo et al.

Soil corrosion is a critical durability and cost factor for metallic foundations in photovoltaic (PV) power plants, yet it is still addressed with fragmented criteria compared with atmospheric corrosion. This paper reviews the main soil corrosivity drivers relevant to PV installations—moisture and aeration dynamics, electrical resistivity, pH and buffer capacity, dissolved ions (notably chlorides and sulfates), microbiological activity, hydro-climatic variability and geological heterogeneity—highlighting their coupled and non-linear effects, such as differential aeration, macrocell formation and corrosion localization. Building on this mechanistic basis, an engineering-oriented methodological roadmap is proposed to translate soil characterization into durability decisions. The approach combines soil corrosivity classification according to DIN 50929-3 and DVGW GW 9, tiered estimation of hot-dip galvanized coating consumption using AASHTO screening, resistivity–pH correlations and ionic penalty factors, and verification against conservative NBS envelopes. When coating life is insufficient, a traceable steel thickness allowance based on DIN bare-steel corrosion rates is introduced to meet the target service life. The framework provides a practical and auditable basis for durability design and risk control of PV foundations in heterogeneous soils. The proposed framework shows that, for soils exceeding AASHTO mild criteria, zinc corrosion rates may increase by a factor of 1.3–1.7 when chloride and sulfate penalties are considered, potentially reducing coating service life by more than 40%. The methodology proposed enables designers to estimate the penalty factors for sulfates (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>f</mi></mrow><mrow><mi>p</mi></mrow></msub><mfenced separators="|"><mrow><msubsup><mrow><mi>S</mi><mi>O</mi></mrow><mrow><mn>4</mn></mrow><mrow><mn>2</mn><mo>−</mo></mrow></msubsup></mrow></mfenced></mrow></semantics></math></inline-formula>) and chlorides (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>f</mi></mrow><mrow><mi>p</mi></mrow></msub><mfenced separators="|"><mrow><msup><mrow><mi>C</mi><mi>l</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></mfenced></mrow></semantics></math></inline-formula>) in each specific project, calculating the appropriate values of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>K</mi></mrow><mrow><msubsup><mrow><mi>S</mi><mi>O</mi></mrow><mrow><mn>4</mn></mrow><mrow><mn>2</mn><mo>−</mo></mrow></msubsup></mrow></msub></mrow></semantics></math></inline-formula> and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>K</mi></mrow><mrow><msup><mrow><mi>C</mi><mi>l</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></msub></mrow></semantics></math></inline-formula> using electrochemical techniques—ER/LPR and EIS—to estimate the effect of the soluble salts content in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>Z</mi><mi>n</mi></mrow><mrow><mi>C</mi><mi>o</mi><mi>r</mi><mi>r</mi><mo> </mo><mi>R</mi><mi>a</mi><mi>t</mi><mi>e</mi></mrow></msub></mrow></semantics></math></inline-formula>, not properly catch by the proxy indicator <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mrow><mi>V</mi></mrow><mrow><mi>c</mi><mi>o</mi><mi>r</mi><mi>r</mi></mrow></msub><mfenced separators="|"><mrow><mi>E</mi><mi>R</mi><mo>,</mo><mo> </mo><mi>p</mi><mi>H</mi></mrow></mfenced></mrow></semantics></math></inline-formula> when sulfate and chloride content are over AAHSTO limits for mildly corrosive soils.

L. Dugerdil, L. Dugerdil, S. Joannin et al.

<p>Past temperature reconstructions offer valuable insights into the impact of climate change on the global climate-human-vegetation system. Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are recognized as effective temperature proxies, particularly in lakes and peatlands, where they are well preserved. However, their reliability as palaeothermometers can be compromised by factors beyond air temperature, especially in drylands. This study investigates the recently compiled Arid Central Asian (ACA) brGDGT surface Data Base, a regional dataset consisting of 753 surface samples from the drylands of ACA. The distribution of brGDGTs in relation to climate and environmental variables was analysed to explore their potential as reliable temperature proxies, mainly focusing on brGDGTs methylation (MBT), cyclisation (CBT), and isomer (IR) indices. The brGDGT-based palaeothermometer is a promising tool for understanding past climates, but our comparison between an ACA-centred database and a worldwide continental surface sample database reveals several challenges. Drylands exhibit extreme climate and soil/lacustrine properties, amplifying the impact of confounding factors on brGDGT-based relationships with mean annual air temperature. Salinity emerges as the dominant factor influencing brGDGT variance, followed by sample type, pH, and aridity, all of which contribute significantly. These factors interact in complex ways, with the salinity effect varying between soil and lacustrine deposits. For sample physicochemical conditions, the <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi mathvariant="normal">IR</mi><mrow><mn mathvariant="normal">6</mn><mo>+</mo><mn mathvariant="normal">7</mn><mi mathvariant="normal">Me</mi></mrow><mo>′</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="39pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="404d15cb413636fa72b31d758eb2b8e4"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-23-1013-2026-ie00001.svg" width="39pt" height="15pt" src="bg-23-1013-2026-ie00001.png"/></svg:svg></span></span> index is best for salinity, and <span class="inline-formula">IR_6Me</span> is most suitable for pH reconstruction. Thus, the <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi mathvariant="normal">MBT</mi><mrow><mn mathvariant="normal">5</mn><mi mathvariant="normal">Me</mi></mrow><mo>′</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="41pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="d2673fdb423b1b85cfcf4412eef2b9e6"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-23-1013-2026-ie00002.svg" width="41pt" height="15pt" src="bg-23-1013-2026-ie00002.png"/></svg:svg></span></span>-temperature relationship is limited in ACA, particularly for lacustrine samples, and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi mathvariant="normal">MBT</mi><mrow><mn mathvariant="normal">6</mn><mi mathvariant="normal">Me</mi></mrow><mo>′</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="41pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="f4039b5ba56e3721568134c666667476"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-23-1013-2026-ie00003.svg" width="41pt" height="15pt" src="bg-23-1013-2026-ie00003.png"/></svg:svg></span></span> does not offer a better solution under hyper- to semi-arid conditions. Sub-calibrating models for specific environmental conditions such as salinity and aridity improves the accuracy of temperature reconstructions. Furthermore, the difference between <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M5" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi mathvariant="normal">MBT</mi><mrow><mn mathvariant="normal">5</mn><mi mathvariant="normal">Me</mi></mrow><mo>′</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="41pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="0a684ebc852fb94664967095c4a428eb"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-23-1013-2026-ie00004.svg" width="41pt" height="15pt" src="bg-23-1013-2026-ie00004.png"/></svg:svg></span></span> and <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mrow><msubsup><mi mathvariant="normal">MBT</mi><mrow><mn mathvariant="normal">6</mn><mi mathvariant="normal">Me</mi></mrow><mo>′</mo></msubsup></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="41pt" height="15pt" class="svg-formula" dspmath="mathimg" md5hash="6bb188ac6753569566e722fa36cae38a"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-23-1013-2026-ie00005.svg" width="41pt" height="15pt" src="bg-23-1013-2026-ie00005.png"/></svg:svg></span></span> provides a promising proxy to assess aridity. Although the brGDGT signal in drylands is influenced by multiple controlling factors, it remains a valuable tool for understanding past climate and environmental conditions, especially when accounting for the complex interactions between these factors based on each study's unique physicochemical and bioclimatic context. Further research, incorporating a broader range of surface samples alongside comprehensive soil and climate data, holds the potential to enhance the accuracy of brGDGT-based climate reconstructions.</p>

Sarina M. Sutter, Markus Penz, Michael Ruggenthaler et al.

We extend a previous result [Sutter et al., J. Phys. A: Math. Theor. 57, 475202 (2024)] to give an explicit form of the set of $v$-representable densities on the one-dimensional torus with any fixed number of particles in contact with a heat bath at finite temperature. The particle interaction has to satisfy some mild assumptions but is kept entirely general otherwise. For densities, we consider the Sobolev space $H^1$ and exploit the convexity of the functionals. This leads to a broader set of potentials than the usual $L^p$ spaces and encompasses distributions. By including temperature and thus considering all excited states in the Gibbs ensemble, Gâteaux differentiability of the thermal universal functional is guaranteed. This yields $v$-representability and it is demonstrated that the given set of $v$-representable densities is even maximal.

Siyu Ren, Yinghui Liu, Pei He et al.

Elucidating the effects of nitrogen and water addition on N₂O dynamics is critical, as N₂O is a key driver of climate change (including nitrogen deposition and shifting precipitation patterns) and stratospheric ozone depletion. The temperate steppe is a notable natural source of this potent greenhouse gas. This study uses field observations and soil sampling to investigate the seasonal pattern of N₂O emissions in the temperate steppe of Inner Mongolia and the mechanism by which nitrogen and water additions, as two different types of factors, alter this seasonal pattern. It explores the regulatory roles of environmental factors, soil physicochemical properties, microbial community structure, and abundance of functional genes in influencing N₂O emissions. These results indicate that the effects of nitrogen and water addition on N₂O emission mechanisms vary throughout the growing season. Nitrogen application consistently increase N₂O emissions. In contrast, water addition suppresses N₂O emissions during the early growing season but promotes emissions during the peak and late growing seasons. In the early growing season, nitrogen addition primarily increased the dissolved organic nitrogen (DON) levels, which provided a matrix for nitrification and promoted N₂O emissions. Meanwhile, water addition increased soil moisture, enhancing the abundance of the <i>nosZ</i> (nitrous oxide reductase) gene while reducing nitrate nitrogen (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msubsup><mrow><mi mathvariant="normal">N</mi><mi mathvariant="normal">O</mi></mrow><mn>3</mn><mo>−</mo></msubsup></semantics></math></inline-formula>-N) levels, as well as AOA (ammonia-oxidizing archaea) <i>amoA</i> and AOB (ammonia-oxidizing bacteria) <i>amoA</i> gene expression, thereby lowering N₂O emissions. During the peak growing season, nitrogen’s role in adjusting pH and ammonium nitrogen (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msubsup><mrow><mi mathvariant="normal">N</mi><mi mathvariant="normal">H</mi></mrow><mn>4</mn><mo>+</mo></msubsup></semantics></math></inline-formula>-N), along with amplifying AOB <i>amoA</i>, spiked N₂O emissions. Water addition affects the balance between nitrification and denitrification by altering aerobic and anaerobic soil conditions, ultimately increasing N₂O emissions by inhibiting <i>nosZ</i>. As the growing season waned and precipitation decreased, temperature also became a driver of N₂O emissions. Structural equation modeling reveals that the impacts of nitrogen and water on N₂O flux variations through nitrification and denitrification are more significant during the peak growing season. This research uncovers innovative insights into how nitrogen and water additions differently impact N₂O dynamics across various stages of the growing season in the temperate steppe, providing a scientific basis for predicting and managing N₂O emissions within these ecosystems.

S. Bianco, S. Bianco, S. Bianco et al.

<p>Studies on CO<span class="inline-formula">₂</span> effects on coccolithophores, unicellular calcifying phytoplankton, show species-specific responses, although only fewer than 5 % of the <span class="inline-formula">∼</span> 280 living species have been tested so far. <i>Helicosphaera carteri</i> significantly contributes to carbon fluxes and CaCO<span class="inline-formula">₃</span> storage due to its size and high calcite production. Despite its importance, few studies have examined <i>H. carteri</i> under experimental conditions, and only one has addressed the effects of rising CO<span class="inline-formula">₂</span>/decreasing pH. <i>H. carteri</i> being a large-sized, obligated calcifier species, an important aspect to understand is how changes in seawater carbonate chemistry may affect its morphology. It has already been suggested for other coccolithophores species that the presence of malformed coccoliths may represent a disadvantage for these organisms. Moreover, an alteration in coccolith morphology may affect their contribution to CaCO<span class="inline-formula">₃</span> sedimentation and ballasting. As for <i>H. carteri</i>, it has also been suggested that due to its high <span class="inline-formula">PIC:POC</span> ratio, the species could show a high sensitivity to CO<span class="inline-formula">₂</span> rise. In this study, we investigate for the first time whether high <span class="inline-formula"><i>p</i></span>CO<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M11" display="inline" overflow="scroll" dspmath="mathml"><mrow><msub><mi/><mn mathvariant="normal">2</mn></msub><mo>/</mo></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="13pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="3893fa1895987b3f7aa0444298f8eafe"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-22-1821-2025-ie00001.svg" width="13pt" height="14pt" src="bg-22-1821-2025-ie00001.png"/></svg:svg></span></span>low pH does affect the morphology of <i>H. carteri</i> coccoliths, by culturing this species under pre-industrial CO<span class="inline-formula">₂</span> levels (<span class="inline-formula">∼</span> 295 <span class="inline-formula">µ</span>atm) and <span class="inline-formula">∼</span> 600 <span class="inline-formula">µ</span>atm, i.e., the SSP 2-4.5 scenario for 2100 (IPCC, 2021). We also analyzed cellular PIC and POC quotas using morphometric data, roundness, and protoplast and coccosphere size to observe the <span class="inline-formula"><i>p</i></span>CO<span class="inline-formula">₂</span> influence on the calcification and photosynthesis ratio.</p> <p>Our results indicate that <i>H. carteri</i> morphology is not significantly affected by increasing CO<span class="inline-formula">₂</span>, in contrast to other heavily calcified species. The protoplast volume and coccosphere shape of <i>Helicosphaera carteri</i> did not vary with changes in CO<span class="inline-formula">₂</span>, and neither did its particulate inorganic carbon (PIC) and particulate organic carbon (POC) quotas, nor the <span class="inline-formula">PIC:POC</span> ratio, indicating unaltered physiological state.</p> <p>The low <span class="inline-formula">PIC:POC</span> ratio found in this work for <i>H. carteri</i> compared to ratios previously measured in the same strain under different experimental conditions, and compared to other highly calcified species, could explain the observed low sensitivity of <i>H. carteri </i>to CO<span class="inline-formula">₂</span>. Moreover, the observation of a stable ratio between calcification and photosynthesis in <i>H. carteri</i> under increasing CO<span class="inline-formula">₂</span> might suggest a constant contribution to the rain ratio under climate change. However, further studies comparing experimental and field data from past ocean acidification events will be required to confirm the conclusions drawn here.</p>

Fernando Flores, Daniel G. Trabada, Álvaro Martín-Rodero et al.

In order to elucidate the mechanism creating superconductivity in the 2-dimensional layer of a p-doped Sn/Si(111) surface, we have analyzed the many-body effects associated with the electron-phonon (e-ph) coupling and the electron–electron interaction. First, we have calculated the DFT surface band of the system and the coupling associated with the different interactions. In our calculations we find a mean field (DFT) electron bandwidth of 0.54 eV, an attractive coupling <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>U</mi><mrow><mi>n</mi><mi>e</mi><mi>g</mi></mrow></msup><mo>=</mo><mn>0.32</mn></mrow></semantics></math></inline-formula> eV associated with the e-ph coupling and an effective electron–electron Hubbard repulsion of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>U</mi><mo>=</mo><mn>0.83</mn></mrow></semantics></math></inline-formula> eV. Then, we analyze the Hubbard Hamiltonian, neglecting in this step the e-ph coupling that is much smaller than the Hubbard coupling, by considering a p-doping in this Hamiltonian of 10%; by means of a Dynamical Mean Field (DMF) approach combined with an interpolative calculation for the self-energy, we deduce the local density of states (DOS) and show that the quasi-particle DOS induced by the doping is not large enough to induce magnetism in the Sn-monolayer. This leads us to analyze the possibility of having superconductivity by considering the attractive interaction induced by the e-ph coupling within an appropriate BCS-Hamiltonian. Our calculations show that the quasiparticle metallic system has a superconductivity critical temperature of ≈7–9 K, in good agreement with experiments.

Shuai Zhang, Caizhang Wu, Zhike Zhao et al.

We reported a highly efficient electrochemical immunosensor utilizing chitosan–graphene nanosheets (CS-GNs) nanocomposites for the detection of aflatoxin B₁ (AFB₁) in corn samples. The CS-GNs nanocomposites, serving as a modifying layer, provide a significant specific surface area and biocompatibility, thereby enhancing both the electron transfer rate and the efficiency of antibody immobilization. The electrochemical characterization was conducted utilizing both differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Moreover, the antibody concentration, pH, antibody immobilization time, and immunoreaction time, were optimized. The results showed that the current change (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>Δ</mo><mi>I</mi></mrow></semantics></math></inline-formula>) before and after the immunoreaction demonstrated a strong linear relationship (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>R</mi><mn>2</mn></msup><mo>=</mo><mn>0.990</mn></mrow></semantics></math></inline-formula>) with the AFB₁ concentration, as well as good specificity and stability. The linear range extended from 0.05 to 25 ng/mL, with a detection limit of 0.021 ng/mL (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>S</mi><mo>/</mo><mi>N</mi><mo>=</mo><mn>3</mn></mrow></semantics></math></inline-formula>). The immunosensor exhibited a recovery rate ranging from 97.3% to 101.4% in corn samples, showing a promising performance using an efficient method, and indicating a remarkable prospect for the detection of fungal toxins in grains.

Rafael Hernandez Heredero, Decio Levi, Christian Scimiterna

In this article we present the results obtained applying the multiple scale expansion up to the order $\varepsilon^6$ to a dispersive multilinear class of equations on a square lattice depending on 13 parameters. We show that the integrability conditions given by the multiple scale expansion give rise to 4 nonlinear equations, 3 of which seem to be new, depending at most on 2 parameters.

Asim Najmi, Zia ur Rehman, Hassan Ahmed Alhazmi et al.

Aim: Bosutinib (BST) is an anti-cancer medicine that is used to treat a variety of different types of cancer. Using the HPLC method of analysis and the Quality by Design (QbD) strategy, the study aimed to precisely quantify the drug in tablet form and in rat plasma. Methodology: For the developed method’s validation, the chromatographic settings were fine-tuned by making use of the Box–Behnken Design (BBD). In the BBD, two dependent variables and three independent variables were selected. Isocratically, samples were eluted, having eluent phase composition of ammonium acetate (CH₃COONH₄) buffer pH 3.0 and acetonitrile (CH₃CN) (60:40% <i>v</i>/<i>v</i>), in Raptor C-18 column at temperature 25 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mo>∘</mo></msup></semantics></math></inline-formula>C with a flow rate of 1 mL/min for 5 min. The wavelength of detection was set at 260 nm. In this study, encorafenib (ENC) was employed as an internal standard. Result: A sharp and resolved peak of BST and ENC at a retention time of 1.92 min and 4.01 min, respectively, was observed by the developed method. The limits of quantification and detection of the newly established method were found to be 1.503 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="sans-serif">μ</mi></semantics></math></inline-formula>g/mL⁻¹ and 0.496 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="sans-serif">μ</mi></semantics></math></inline-formula>g/mL⁻¹. The calibration curve’s observed linearity range was between 2 and 20 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="sans-serif">μ</mi></semantics></math></inline-formula>g/mL⁻¹, with an r² of 0.999. The developed and optimized method was verified in compliance with the ICH guidelines. The results of all validation parameters were within the acceptable range, for example, % RSD of system suitability (0.63–4.46), % RSD of linear regression (1.659), interday and intraday precision % RSD value (1.723–1.892), and (1.762–1.923), respectively, and accuracy (1.476–1.982). Conclusion: The quantity of BST in tablet dosage form and in rat plasma samples was determined using a simple, quick, and robust method that was devised and validated.

Yan Sheng, Wan-Yi Wang, Ming-Feng Wu et al.

In the study, papain was chosen from five proteases to hydrolyze proteins of monkfish swim bladders for effectively utilizing monkfish (<i>Lophius litulon</i>) processing byproducts, and the hydrolysis conditions of papain were optimized as hydrolysis temperature of 65 °C, pH 7.5, enzyme dose 2.5% and time 5 h using single-factor and orthogonal experiments. Eighteen peptides were purified from the swim bladder hydrolysate of monkfish by ultrafiltration and gel permeation chromatography methods and identified as YDYD, QDYD, AGPAS, GPGPHGPSGP, GPK, HRE, GRW, ARW, GPTE, DDGGK, IGPAS, AKPAT, YPAGP, DPT, FPGPT, GPGPT, GPT and DPAGP, respectively. Among eighteen peptides, GRW and ARW showed significant DPPH· scavenging activities with EC₅₀ values of 1.053 ± 0.003 and 0.773 ± 0.003 mg/mL, respectively; YDYD, QDYD, GRW, ARW and YPAGP revealed significantly HO· scavenging activities with EC₅₀ values of 0.150 ± 0.060, 0.177 ± 0.035, 0.201 ± 0.013, 0.183 ± 0.0016 and 0.190 ± 0.010 mg/mL, respectively; YDYD, QDYD, ARW, DDGGK and YPAGP have significantly <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msubsup><mi mathvariant="normal">O</mi><mn>2</mn><mo>−</mo></msubsup><mo>·</mo></mrow></semantics></math></inline-formula> scavenging capability with EC₅₀ values of 0.126 ± 0.0005, 0.112 ± 0.0028, 0.127 ± 0.0002, 0.128 ± 0.0018 and 0.107 ± 0.0002 mg/mL, respectively; and YDYD, QDYD and YPAGP showed strong ABTS⁺· scavenging ability with EC₅₀ values of 3.197 ± 0.036, 2.337 ± 0.016 and 3.839 ± 0.102 mg/mL, respectively. YDYD, ARW and DDGGK displayed the remarkable ability of lipid peroxidation inhibition and Ferric-reducing antioxidant properties. Moreover, YDYD and ARW can protect Plasmid DNA and HepG2 cells against H₂O₂-induced oxidative stress. Furthermore, eighteen isolated peptides had high stability under temperatures ranging from 25–100 °C; YDYD, QDYD, GRW and ARW were more sensitive to alkali treatment, but DDGGK and YPAGP were more sensitive to acid treatment; and YDYD showed strong stability treated with simulated GI digestion. Therefore, the prepared antioxidant peptides, especially YDYD, QDYD, GRW, ARW, DDGGK and YPAGP from monkfish swim bladders could serve as functional components applied in health-promoting products because of their high-antioxidant functions.

Massimo Ostilli, Carlo Presilla

We formalize and prove the extension to finite temperature of a class of quantum phase transitions, acting as condensations in the space of states, recently introduced and discussed at zero temperature~(Ostilli and Presilla 2021 \textit{J. Phys. A: Math. Theor.} \textbf{54} 055005). In details, we find that if, for a quantum system at canonical thermal equilibrium, one can find a partition of its Hilbert space $\mathcal{H}$ into two subspaces, $\mathcal{H}_\mathrm{cond}$ and $\mathcal{H}_\mathrm{norm}$, such that, in the thermodynamic limit, $\dim \mathcal{H}_\mathrm{cond}/ \dim \mathcal{H} \to 0$ and the free energies of the system restricted to these subspaces cross each other for some value of the Hamiltonian parameters, then, the system undergoes a first-order quantum phase transition driven by those parameters. The proof is based on an exact probabilistic representation of quantum dynamics at an imaginary time identified with the inverse temperature of the system. We also show that the critical surface has universal features at high and low temperatures.

Anna A. Vedernikova, Mikhail D. Miruschenko, Irina A. Arefina et al.

Today, the development of nanomaterials with sensing properties attracts much scientific interest because of the demand for low-cost nontoxic colloidal nanoprobes with high sensitivity and selectivity for various biomedical and environment-related applications. Carbon dots (CDs) are promising candidates for these applications as they demonstrate unique optical properties with intense emissions, biocompatibility, and ease of fabrication. Herein, we developed synthesis protocols to obtain CDs based on o-phenylenediamine with a variety of optical responses depending on additional precursors and changes in the reaction media. The obtained CDs are N-doped (N,S-doped in case of thiourea addition) less than 10 nm spherical particles with emissions observed in the 300–600 nm spectral region depending on their chemical composition. These CDs may act simultaneously as absorptive/fluorescent sensing probes for solvent polarity with <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>∆</mo><mi mathvariant="normal">S</mi><mo>/</mo><mo>∆</mo><msubsup><mi mathvariant="normal">E</mi><mi mathvariant="normal">N</mi><mi mathvariant="normal">T</mi></msubsup><mo> </mo></mrow></semantics></math></inline-formula> up to 85, for <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mo>∆</mo><msubsup><mi mathvariant="normal">E</mi><mi mathvariant="normal">N</mi><mi mathvariant="normal">T</mi></msubsup></mrow></semantics></math></inline-formula> from 0.099 to 1.0 and for pH values in the range of 3.0–8.0, thus opening an opportunity to check the pH in non-pure water or a mixture of solvents. Moreover, CDs preserve their optical properties when embedded in cellulose strips that can be used as sensing probes for fast and easy pH checks. We believe that the resulting dual-purpose sensing nano probes based on CDs will have high demand in various sensing applications.

Gaoyang Liu, Faguo Hou, Xindong Wang et al.

Recently, nickel phosphides (Ni-P) in an amorphous state have emerged as potential catalysts with high intrinsic activity and excellent electrochemical stability for hydrogen evolution reactions (HER). However, it still lacks a good strategy to prepare amorphous Ni-P with rich surface defects or structural boundaries, and it is also hard to construct a porous Ni-P layer with favorable electron transport and gas–liquid transport. Herein, an integrated porous electrode consisting of amorphous Ni-P and a Ni interlayer was successfully constructed on a 316L stainless steel felt (denoted as Ni-P/Ni-316L). The results demonstrated that the pH of the plating solution significantly affected the grain size, pore size and distribution, and roughness of the cell-like particle surface of the amorphous Ni-P layer. The Ni-P/Ni-316L prepared at pH = 3 presented the richest surface defects or structural boundaries as well as porous structure. As expected, the as-developed Ni-P/Ni-316L demonstrated the best kinetics, with <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>η</mi><mrow><mn>10</mn></mrow></msub></mrow></semantics></math></inline-formula> of 73 mV and a Tafel slope of ca. 52 mV dec-1 for the HER among all the electrocatalysts prepared at various pH values. Furthermore, the Ni-P/Ni-316L exhibited comparable electrocatalytic HER performance and better durability than the commercial Pt (20 wt%)/C in a real water electrolysis cell, indicating that the non-precious metal-based Ni-P/Ni-316L is promising for large-scale processing and practical use.

Grazia Cottone, Letizia Chiodo, Luca Maragliano et al.

Although botulinum neurotoxins (BoNTs) are among the most toxic compounds found in nature, their molecular mechanism of action is far from being elucidated. A key event is the conformational transition due to acidification of the interior of synaptic vesicles, leading to translocation of the BoNT catalytic domain into the neuronal cytosol. To investigate these conformational variations, homology modeling and atomistic simulations are combined to explore the internal dynamics of the sub-types BoNT/A1 (the most-used sub-type in medical applications) and BoNT/E1 (the most kinetically efficient sub-type). This first simulation study of di-chain BoNTs in closed and open states considers the effects of both neutral and acidic pH. The conformational mobility is driven by domain displacements of the ganglioside-binding site in the receptor binding domain, the translocation domain (HC<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mi>NT</mi></msub></semantics></math></inline-formula>) switch, and the belt <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-helix, which present multiple conformations, depending on the primary sequence and the pH. Fluctuations of the belt <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>α</mi></semantics></math></inline-formula>-helix are observed for closed conformations of the toxins and at acidic pH, while patches of more solvent-accessible residues appear under the same conditions in the core translocation domain HC<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mi>NT</mi></msub></semantics></math></inline-formula>. These findings suggest that, during translocation, the higher mobility of the belt could be transmitted to HC<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mi>NT</mi></msub></semantics></math></inline-formula>, leading to the favorable interaction of HC<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mi>NT</mi></msub></semantics></math></inline-formula> residues with the non-polar membrane environment.

Jun-Hui Fan, Ke-Yin Chen, Hu-Bing Xiao et al.

In this work, the support vector machine (SVM) method is adopted to separate BL Lacertae objects (BL Lacs) and flat spectrum radio quasars (FSRQs) in the plots of the photon spectrum index against the photon flux, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi></mrow></semantics></math></inline-formula>, those of the photon spectrum index against the variability index, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mi mathvariant="italic">V</mi><mspace width="-0.166667em"></mspace><mi mathvariant="italic">I</mi></mrow></semantics></math></inline-formula> and those of the variability index against the photon flux, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>log</mi><mspace width="0.166667em"></mspace><mrow><mi>V</mi><mspace width="-0.166667em"></mspace><mi>I</mi></mrow><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi></mrow></semantics></math></inline-formula>. Then, we used the dividing lines to distinguish BL Lacs from FSRQs in the blazar candidates of uncertain types from the <i>Fermi</i>/LAT catalogue. Our main conclusions are: 1. We separate BL Lacs and FSRQs by <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>=</mo><mo>−</mo><mn>0.123</mn><mspace width="0.166667em"></mspace><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi><mo>+</mo><mn>1.170</mn></mrow></semantics></math></inline-formula> in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi></mrow></semantics></math></inline-formula> plot, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>=</mo><mo>−</mo><mn>0.161</mn><mspace width="0.166667em"></mspace><mi>log</mi><mspace width="0.166667em"></mspace><mrow><mi>V</mi><mspace width="-0.166667em"></mspace><mi>I</mi></mrow><mo>+</mo><mn>2.594</mn></mrow></semantics></math></inline-formula> in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>α</mi><mi>ph</mi></msub><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mrow><mi>V</mi><mspace width="-0.166667em"></mspace><mi>I</mi></mrow></mrow></semantics></math></inline-formula> plot and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>log</mi><mspace width="0.166667em"></mspace><mrow><mi>V</mi><mspace width="-0.166667em"></mspace><mi>I</mi></mrow><mo>=</mo><mn>0.792</mn><mspace width="0.166667em"></mspace><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi><mo>+</mo><mn>9.203</mn></mrow></semantics></math></inline-formula> in the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>log</mi><mspace width="0.166667em"></mspace><mrow><mi>V</mi><mspace width="-0.166667em"></mspace><mi>I</mi></mrow><mo>∼</mo><mi>log</mi><mspace width="0.166667em"></mspace><mi>F</mi></mrow></semantics></math></inline-formula> plot. 2. We obtain 932 BL Lac candidates and possible BL Lac candidates, and 585 FSRQ candidates and possible FSRQ candidates. 3. Discussion is given regarding comparisons with the literature.

N. Schleinkofer, N. Schleinkofer, D. Evans et al.

<p><i>Hyrrokkin sarcophaga</i> is a parasitic foraminifera that is commonly found in cold-water coral reefs where it infests the file clam <i>Acesta excavata</i> and the scleractinian coral <i>Desmophyllum pertusum</i> (formerly known as <i>Lophelia pertusa)</i>. Here, we present measurements of the trace element and isotopic composition of these parasitic foraminifera, analyzed by inductively coupled optical emission spectrometry (ICP-OES), electron probe microanalysis (EPMA) and mass spectrometry (gas-source MS and inductively-coupled-plasma MS).</p> <p>Our results reveal that the geochemical signature of <i>H. sarcophaga</i> depends on the host organism it infests. Sr <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M1" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="1b4178c77ca0d4bfee6c9ddd864f3a43"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-4733-2021-ie00001.svg" width="8pt" height="14pt" src="bg-18-4733-2021-ie00001.png"/></svg:svg></span></span> Ca ratios are 1.1 mmol mol<span class="inline-formula">⁻¹</span> higher in <i>H. sarcophaga</i> that infest <i>D. pertusum</i>, which could be an indication that dissolved host carbonate material is utilized in shell calcification, given that the aragonite of <i>D. pertusum</i> has a naturally higher Sr concentration compared to the calcite of <i>A. excavata</i>. Similarly, we measure 3.1 ‰ lower <span class="inline-formula"><i>δ</i>¹³</span>C and 0.25 ‰ lower <span class="inline-formula"><i>δ</i>¹⁸</span>O values in <i>H. sarcophaga</i> that lived on <i>D. pertusum</i>, which might be caused by the direct uptake of the host's carbonate material with a more negative isotopic composition or different pH regimes in these foraminifera (pH can exert a control on the extent of CO<span class="inline-formula">₂</span> hydration/hydroxylation) due to the uptake of body fluids of the host. We also observe higher Mn <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M6" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="073414a2b77546d8d5847ae97897d626"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-4733-2021-ie00002.svg" width="8pt" height="14pt" src="bg-18-4733-2021-ie00002.png"/></svg:svg></span></span> Ca ratios in foraminifera that lived on <i>A. excavata</i> but did not penetrate the host shell compared to specimen that penetrated the shell, which could be interpreted as a change in food source, changes in the calcification rate, Rayleigh fractionation or changing oxygen conditions.</p> <p>While our measurements provide an interesting insight into the calcification process of this unusual foraminifera, these data also indicate that the geochemistry of this parasitic foraminifera is unlikely to be a reliable indicator of paleoenvironmental conditions using Sr <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M7" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="36bd7baae116a5efc17e692d563c2b51"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-4733-2021-ie00003.svg" width="8pt" height="14pt" src="bg-18-4733-2021-ie00003.png"/></svg:svg></span></span> Ca, Mn <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M8" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="fb147fccdcf98a9911cf3d26a8f6dc33"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-18-4733-2021-ie00004.svg" width="8pt" height="14pt" src="bg-18-4733-2021-ie00004.png"/></svg:svg></span></span> Ca, <span class="inline-formula"><i>δ</i>¹⁸</span>O or <span class="inline-formula"><i>δ</i>¹³</span>C unless the host organism is known and its geochemical composition can be accounted for.</p>

Nathaniel Brochu, Benjamin Belanger-Huot, Dmytro Humeniuk et al.

This paper describes a two-cycle bacteria energy recovery system (BERS) to power two embedded sensors: an ultra-low portable pH sensor and a sound sensor. The designed unit can handle up to seven microbial fuel cells (MFCs) to charge a super-capacitor. This allows the BERS to provide a constant 0.14 mW without further electrical components for signal conditioning. The two cycles were driven with a 100 k<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi mathvariant="sans-serif">Ω</mi></semantics></math></inline-formula> load and a 10 Hz frequency. The BERS is also self-powered with an integrated start-up unit to be self-activated when the MFCs charge the energy-storing unit after three days. The BERS powered pH sensor has an error below 5% at 25 <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msup><mrow></mrow><mo>∘</mo></msup></semantics></math></inline-formula>C and is able to work continuously while being activated for 4 h. The performances of the pH and sound sensors were determined based on a compromise between accuracy and power consumption.

Shruti Kulkarni, S. B. Patil, S. Mishra et al.

Context: This study is aimed to analyse heavy metal content and antioxidant potential of three types of Jamun honey samples from Western Ghats of India. Ash, pH, and colour intensity were anlyased. Heavy metal analysis for Arsenic (As), Lead (Pb), chromium (Cr) and Mercury (Hg) were carried out using inductively coupled plasma - optical emission spectrometry (ICP-OES). Total polyphenol (TPC), total flavonoid content (TFC) and antioxidant assays such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) were performed. Comparative studies of Jamun honeys revealed strong correlation between TPC and TFC as significant radical scavenging activities. Colour values represented strong correlation with TPC and TFC at (r= 0.9) and FRAP at (r= 0.8) whereas a negative correlation with IC 50 values of DPPH at (r= -0.6) was observed.

Yuto Moriwaki

We introduce the notion of a genus and its mass for vertex algebras. For lattice vertex algebras, their genera are the same as those of lattices, which plays an important role in the classification of lattices. We derive a formula relating the mass for vertex algebras to that for lattices, and then give a new characterization of some holomorphic vertex operator algebras.

J. Hepp, J. Hepp, I. K. Schäfer et al.

<p>Molecular fossils, like bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs), and the stable isotopic composition of biomarkers, such as <span class="inline-formula"><i>δ</i>²H</span> of leaf wax-derived <span class="inline-formula"><i>n</i></span>-alkanes (<span class="inline-formula"><i>δ</i>²H</span><span class="inline-formula">_{<i>n</i>-alkane}</span>) or <span class="inline-formula"><i>δ</i>¹⁸O</span> of hemicellulose-derived sugars (<span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_sugar</span>), are increasingly used for the reconstruction of past climate and environmental conditions. Plant-derived <span class="inline-formula"><i>δ</i>²H</span><span class="inline-formula">_{<i>n</i>-alkane}</span> and <span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_sugar</span> values record the isotopic composition of plant source water (<span class="inline-formula"><i>δ</i>²</span>H<span class="inline-formula">_source-water</span> and <span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_source-water</span>), which usually reflects mean annual precipitation (<span class="inline-formula"><i>δ</i>²</span>H<span class="inline-formula">_precipiation</span> and <span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_precipiation</span>), modulated by evapotranspirative leaf water enrichment and biosynthetic fractionation (<span class="inline-formula"><i>ε</i>_bio</span>). Accuracy and precision of respective proxies should be ideally evaluated at a regional scale. For this study, we analysed topsoils below coniferous and deciduous forests as well as grassland soils along a central European transect in order to investigate the variability and robustness of various proxies and to identify effects related to vegetation. Soil pH values derived from brGDGTs correlate reasonably well with measured soil pH values but are systematically overestimated (<span class="inline-formula">Δ</span>pH&thinsp;<span class="inline-formula">=</span>&thinsp;<span class="inline-formula">0.6±0.6</span>). The branched vs. isoprenoid tetraether index (BIT) can give some indication whether the pH reconstruction is reliable. Temperatures derived from brGDGTs overestimate mean annual air temperatures slightly (<span class="inline-formula">Δ<i>T</i>_MA=0.5</span>&thinsp;<span class="inline-formula">^∘</span>C&thinsp;<span class="inline-formula">±</span>&thinsp;2.4). Apparent isotopic fractionation (<span class="inline-formula"><i>ε</i>_{<i>n</i>-alkane/precipitation}</span> and <span class="inline-formula"><i>ε</i>_{sugar∕precipitation}</span>) is lower for grassland sites than for forest sites due to signal damping; i.e. grass biomarkers do not record the full evapotranspirative leaf water enrichment. Coupling <span class="inline-formula"><i>δ</i>²H</span><span class="inline-formula">_{<i>n</i>-alkane}</span> with <span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_sugar</span> allows us to reconstruct the stable isotopic composition of the source water more accurately than without the coupled approach (<span class="inline-formula">Δ<i>δ</i>²H</span>&thinsp;<span class="inline-formula">=</span>&thinsp;<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M39" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>∼</mo><mo>-</mo><mn mathvariant="normal">21</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="32pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="e82a4d8b4a959976b462fc4efa2646e9"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-17-741-2020-ie00001.svg" width="32pt" height="10pt" src="bg-17-741-2020-ie00001.png"/></svg:svg></span></span>&thinsp;‰&thinsp;<span class="inline-formula">±</span>&thinsp;22&thinsp;‰ and <span class="inline-formula">Δ<i>δ</i>¹⁸O</span>&thinsp;<span class="inline-formula">=</span>&thinsp;<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M43" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>∼</mo><mo>-</mo><mn mathvariant="normal">2.9</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="35pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="fa28c201b7bdb30ed9d566e4ac581654"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-17-741-2020-ie00002.svg" width="35pt" height="10pt" src="bg-17-741-2020-ie00002.png"/></svg:svg></span></span>&thinsp;‰&thinsp;<span class="inline-formula">±</span>&thinsp;2.8&thinsp;‰). Similarly, relative humidity during daytime and the vegetation period (RH<span class="inline-formula">_MDV</span>) can be reconstructed using the coupled isotope approach (<span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M46" display="inline" overflow="scroll" dspmath="mathml"><mrow><mi mathvariant="normal">Δ</mi><msub><mi mathvariant="normal">RH</mi><mi mathvariant="normal">MDV</mi></msub><mo>=</mo><mo>∼</mo><mo>-</mo><mn mathvariant="normal">17</mn><mo>±</mo><mn mathvariant="normal">12</mn></mrow></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="107pt" height="12pt" class="svg-formula" dspmath="mathimg" md5hash="d823af5a8ee2834d6d10a3ec7bc50932"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="bg-17-741-2020-ie00003.svg" width="107pt" height="12pt" src="bg-17-741-2020-ie00003.png"/></svg:svg></span></span>). Especially for coniferous sites, reconstructed RH<span class="inline-formula">_MDV</span> values as well as source water isotope composition underestimate the measured values. This can likely be explained by understorey grass vegetation at the coniferous sites contributing significantly to the <span class="inline-formula"><i>n</i></span>-alkane pool but only marginally to the sugar pool in the topsoils. Vegetation-dependent variable signal damping and <span class="inline-formula"><i>ε</i>_bio</span> (regarding <span class="inline-formula">²H</span> between <span class="inline-formula"><i>n</i></span>-alkanes and leaf water) along our European transect are difficult to quantify but likely contribute to the observed underestimation in the source water isotope composition and RH reconstructions. Microclimate variability could cause the rather large uncertainties. Vegetation-related effects do, by contrast, not affect the brGDGT-derived reconstructions. Overall, GDGTs and the coupled <span class="inline-formula"><i>δ</i>²H</span><span class="inline-formula">_{<i>n</i>-alkane}</span>–<span class="inline-formula"><i>δ</i>¹⁸O</span><span class="inline-formula">_sugar</span> approach have great potential for more quantitative paleoclimate reconstructions.</p>