bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous quantitation and identification of intact Nandrolone phase II oxo‐metabolites based on derivatization and inject LC–MS/(HRMS) methodology
Authors: Sakellariou Panagiotis , Kiousi Polyxeni , Petrou Michael , Angelis Yiannis S. 
Published: April 2024

AbstractΑ sensitive and selective derivatization and inject method for the quantification of intact nandrolone phase II oxo‐metabolites was developed and validated using liquid chromatography ‐ (tandem high resolution) mass spectrometry (LC–MS/(HRMS)). For the derivatization, Girard's reagent T (GRT) was used directly in natural urine samples and the analysis of the metabolites of interest was performed by direct injection into LC–MS/(HRMS) system operating in positive ionization mode. Derivatization enabled the efficient detection of nandrolone oxo‐metabolites, while at the same time producing intense product ions under collision‐induced dissociation (CID) conditions that are related to metabolites of the steroid backbone and not to the conjugated moieties. Glucuronide and sulfate metabolites of nandrolone were chromatographically resolved and quantified in the same run in the range of 1–100 ng mL−1, while at the same time structure identification could be performed for each metabolite. Full validation of the method was performed according to the World Anti‐Doping Agency (WADA) International Standard for Laboratories (ISL). Nandrolone oxo‐metabolites were quantified in two sets of urine samples, the first set consisted of real urine samples previously detected as negative and the second set consisted of urine samples collected from two excretion studies after nandrolone decanoate administration. The results for 19‐norandrosterone glucuronide (19‐NAG) and 19‐noretiocholanolone glucuronide (19‐NEG) were compared with those obtained by traditional gas chromatography ‐ (tandem) mass spectrometry (GC–MS/[MS]) method.
Ungulates mitigate the effects of drought and shrub encroachment on the fire hazard ofMediterranean oak woodlands
Authors: Lecomte Xavier , Bugalho Miguel N. , Catry Filipe X. , Fernandes Paulo M. , Cera Andreu , Caldeira Maria C. 
Published: April 2024

AbstractClimate change is increasing the frequency of droughts and the risk of severe wildfires, which can interact with shrub encroachment and browsing by wild ungulates. Wild ungulate populations are expanding due, among other factors, to favorable habitat changes resulting from land abandonment or land‐use changes. Understanding how ungulate browsing interacts with drought to affect woody plant mortality, plant flammability, and fire hazard is especially relevant in the context of climate change and increasing frequency of wildfires. The aim of this study is to explore the combined effects of cumulative drought, shrub encroachment, and ungulate browsing on the fire hazard of Mediterranean oak woodlands in Portugal. In a long‐term (18 years) ungulate fencing exclusion experiment that simulated land abandonment and management neglect, we investigated the population dynamics of the native shrubCistus ladanifer, which naturally dominates the understory of woodlands and is browsed by ungulates, comparing areas with (no fencing) and without (fencing) wild ungulate browsing. We also modeled fire behavior in browsed and unbrowsed plots considering drought and nondrought scenarios. Specifically, we estimatedC. ladaniferpopulation density, biomass, and fuel load characteristics, which were used to model fire behavior in drought and nondrought scenarios. Overall, drought increased the proportion of deadC. ladanifershrub individuals, which was higher in the browsed plots. Drought decreased the ratio of live to dead shrub plant material, increased total fuel loading, shrub stand flammability, and the modeled fire parameters, that is, rate of surface fire spread, fireline intensity, and flame length. However, total fuel load and fire hazard were lower in browsed than unbrowsed plots, both in drought and nondrought scenarios. Browsing also decreased the population density of living shrubs, halting shrub encroachment. Our study provides long‐term experimental evidence showing the role of wild ungulates in mitigating drought effects on fire hazard in shrub‐encroached Mediterranean oak woodlands. Our results also emphasize that the long‐term effects of land abandonment can interact with climate change drivers, affecting wildfire hazard. This is particularly relevant given the increasing incidence of land abandonment.
Achieved dose and treatment discontinuation of candesartan in men and women with chronic heart failure: data from CHARM
Authors: Qin Hailun , Dewan Pooja , Santema Bernadet T. , ter Maaten Jozine M. , Swedberg Karl , McMurray John J. V. , Voors Adriaan A. 
Published: April 2024

AbstractAimsAngiotensin receptor blockers have been shown to reduce heart failure hospitalization and cardiovascular mortality in men and women with heart failure with reduced ejection fraction (HFrEF). It is unknown whether there are differences between men and women in achieved dose and treatment discontinuation due to adverse events of candesartan.Methods and resultsWe conducted a post hoc analysis of the Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity (CHARM) programme. A total of 3172 men and 1106 women with HFrEF [left ventricular ejection fraction (LVEF) ≤ 40%] in New York Heart Association class II–IV were randomized to candesartan or placebo. Every 2 weeks, patients were up‐titrated from 4 or 8, to16, to 32 mg once daily, unless a higher dose was contraindicated or not tolerated. Women were older (66 vs. 64 years), had a higher LVEF (29.9% vs. 28.6%), and had more hypertension (54% vs. 47%) than men. The mean achieved dose of candesartan was 21.5 ± 12.6 mg in men and 20.7 ± 12.9 mg in women (P = 0.19). In both the candesartan and placebo groups, cardiovascular death and heart failure hospitalizations were higher in men and women who achieved lower dose levels. Event rates for achieved dose levels of 0, 4 or 8, 16, and 32 mg candesartan were 20.8, 17.2, 14.0, and 10.1 per 100 person‐years in men, respectively, and 23.6, 13.7, 14.0, and 9.1 per 100 person‐years in women, respectively. In each of the achieved dose levels, there was no sex difference in the proportion of patients with an event, neither in the candesartan group nor in the placebo group (P‐value for all > 0.05). There was no significant interaction between sex and treatment‐related discontinuation for hypotension (P = 0.520), an increase in creatinine (P = 0.102), and hyperkalaemia (P = 0.905).ConclusionsIn a randomized clinical trial in patients with HFrEF, men and women achieved similar doses of candesartan. Primary event rates and treatment‐related discontinuation due to adverse events were also similar between men and women.
Association between pulmonary artery pulsatility and mortality after implantation of left ventricular assist device
Authors: Akamkam Ali , Galand Vincent , Jungling Marie , Delmas Clément , Dambrin Camille , Pernot Mathieu , Kindo Michel , Gaudard Philippe , Rouviere Philippe , Senage Thomas , Chavanon Olivier , Para Marylou , Gariboldi Vlad , Pozzi Matteo , Litzler Pierre‐Yves , Babatasi Gerard , Bouchot Olivier , Radu Costin , Bourguignon Thierry , D'Ostrevy Nicolas , Abi Akar Ramzi , Vanhuyse Fabrice , Gaillard Maïra , Chatelier Gilles , Fels Audrey , Flecher Erwan , Guihaire Julien 
Published: April 2024

AbstractAimsRight ventricular failure after left ventricular assist device (LVAD) implantation is a major concern that remains challenging to predict. We sought to investigate the relationship between preoperative pulmonary artery pulsatility index (PAPi) and mortality after LVAD implantation.Methods and resultsA retrospective analysis of the ASSIST‐ICD multicentre registry allowed the assessment of PAPi before LVAD according to the formula [(systolic pulmonary artery pressure − diastolic pulmonary artery pressure)/central venous pressure]. The primary endpoint was survival at 3 months, according to the threshold value of PAPi determined by the receiver operating characteristic (ROC) curve. A multivariate analysis including demographic, echographic, haemodynamic, and biological variables was performed to identify predictive factors for 2 year mortality. One hundred seventeen patients were included from 2007 to 2021. The mean age was 58.45 years (±13.16), with 15.4% of women (sex ratio 5.5). A total of 53.4% were implanted as bridge to transplant and 43.1% as destination therapy. Post‐operative right ventricular failure was observed in 57 patients (48.7%), with no significant difference between survivors and non‐survivors at 1 month (odds ratio 1.59, P = 0.30). The median PAPi for the whole study population was 2.83 [interquartile range 1.63–4.69]. The threshold value of PAPi determined by the ROC curve was 2.84. Patients with PAPi ≥ 2.84 had a higher survival rate at 3 months [PAPi < 2.84: 58.1% [46.3–72.8%] vs. PAPi ≥ 2.84: 89.1% [81.1–97.7%], hazard ratio (HR) 0.08 [0.02–0.28], P < 0.01], with no significant difference after 3 months (HR 0.67 [0.17–2.67], P = 0.57). Other predictors of 2 year mortality were systemic hypertension (HR 4.22 [1.49–11.97], P < 0.01) and diabetes mellitus (HR 4.90 [1.83–13.14], P < 0.01). LVAD implantation as bridge to transplant (HR 0.18 [0.04–0.74], P = 0.02) and heart transplantation (HR 0.02 [0.00–0.18], P < 0.01) were associated with a higher survival rate at 2 years.ConclusionsPreoperative PAPi < 2.84 was associated with a higher risk of early mortality after LVAD implantation without impacting 2 year outcomes among survivors.
The peptide neuromedin U (NMU) is elevated in NYHA II and III heart failure
Authors: Healy Vincent , O'Hora Therese Ruane , Markos Farouk 
Published: April 2024

AbstractAimsCurrently, there is no reliable biomarker to detect pre‐heart failure in humans. An early risk signal is an elevated left atrial pressure (LAP) and preliminary results from animal studies strongly suggest the neuropeptide neuromedin U (NMU) is released in response to this increase in LAP. However, it is unknown whether NMU is elevated in patients with heart failure. Therefore, the aim of this study was to assess if NMU levels are elevated in human cases of heart failure.Methods and resultsTwenty‐four serum samples were obtained from patients in stage II and III heart failure from the Royal Papworth Hospital in Cambridge UK and tested using a selective NMU‐ELISA; the data were compared with serum obtained commercially from self‐declared healthy donors. NMU concentrations in serum from heart failure patients were significantly higher (P = 0.0007; unpaired Student's t‐test) than control, 8.48 ± 0.67 ng/mL (mean ± SEM) versus 5.43 ± 0.46 ng/mL. There was no significant difference between NYHA stage II and III patients (P = 0.85, unpaired Student's t‐test), which were 8.33 ± 0.89 ng/mL (n = 9) and 8.6 ± 0.95 ng/mL (n = 15), respectively. Only mean right atrial pressure was found to have a significant correlation with serum NMU (R = 0.81, P < 0.00001; regression analysis).ConclusionsNMU is elevated in serum from stage II and III heart failure patients, supporting data from our pre‐heart failure animal model; however, further study is needed to determine whether NMU is a reliable biomarker for pre‐heart failure.
Tumor‐associated macrophages impair NK cell IFN‐γ production and contribute to tumor progression in clear cell renal cell carcinoma
Authors: Núñez Sol Yanel , Trotta Aldana , Regge María Victoria , Amarilla María Sofía , Secchiari Florencia , Sierra Jessica Mariel , Santilli María Cecilia , Gantov Mariana , Rovegno Agustín , Richards Nicolás , Ameri Carlos , Ríos Pita Hernando , Rico Luis , Mieggi Mauro , Vitagliano Gonzalo , Blas Leandro , Friedrich Adrián David , Domaica Carolina Inés , Fuertes Mercedes Beatriz , Zwirner Norberto Walter 
Published: April 2024

AbstractTumor‐associated macrophages (TAM) are abundant in several tumor types and usually correlate with poor prognosis. Previously, we demonstrated that anti‐inflammatory macrophages (M2) inhibit NK cell effector functions. Here, we explored the impact of TAM on NK cells in the context of clear‐cell renal cell carcinoma (ccRCC). Bioinformatics analysis revealed that an exhausted NK cell signature strongly correlated with an M2 signature. Analysis of TAM from human ccRCC samples confirmed that they exhibited an M2‐skewed phenotype and inhibited IFN‐γ production by NK cells. Moreover, human M0 macrophages cultured with conditioned media from ccRCC cell lines generated macrophages with an M2‐skewed phenotype (TAM‐like), which alike TAM, displayed suppressive activity on NK cells. Moreover, TAM depletion in the mouse Renca ccRCC model resulted in delayed tumor growth and reduced volume, accompanied by an increased frequency of IFN‐γ‐producing tumor‐infiltrating NK cells that displayed heightened expression of T‐bet and NKG2D and reduced expression of the exhaustion‐associated co‐inhibitory molecules PD‐1 and TIM‐3. Therefore, in ccRCC, the tumor microenvironment polarizes TAM toward an immunosuppressive profile that promotes tumor‐infiltrating NK cell dysfunction, contributing to tumor progression. In addition, immunotherapy strategies targeting TAM may result in NK cell reinvigoration, thereby counteracting tumor progression.
Structural and Electronic Impacts of the Axial Substitution at the Phosphorus Center of C(sp3)‐Bridged P‐Heterotriangulenes
Authors: Harrer Siegfried , Schühle Johannes D. R. , Neiß Christian , Günthert Marina , Mittmann Lena , Reule Andrea , Leitner Jonas , Rominger Frank , Görling Andreas , Kivala Milan 
Published: April 2024

AbstractThe structural and electronic properties of the dimethylmethylene‐bridged P‐heterotriangulene have been systematically modulated by functionalization of its phosphorus center. The optoelectronic properties of the obtained derivatives in solution were characterized by UV/Vis absorption and emission spectroscopy, cyclic voltammetry and 31P NMR spectroscopy. The solid state structures were analyzed by X‐ray crystallography. The experimental results were corroborated by density functional theory calculations which revealed the crucial influence of the axial substitution on the bowl‐shaped geometry of the phosphorus‐centered polycyclic scaffold, which is proportional to the s‐character of the P−X bond. The advantage of the bowl‐shaped P‐heterotriangulene scaffold was demonstrated by successful co‐crystallization with fullerene C60.
A novel composite electrode based on graphene oxide/MnO2:h‐MoO3 particles for square wave voltammetric determination of acetaminophen
Authors: Aktürk Merve , Dursun Zekerya 
Published: April 2024

AbstractA novel composite electrode was developed based on graphene oxide (GO)/MnO2:h‐MoO3 nanocomposite for sensitive and selective voltammetric detection of acetaminophen (ACP). The composite electrode materials were characterized using X‐Ray photoelectron spectroscopy (XPS), X‐Ray Diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetric (CV) techniques. In the optimum conditions, the oxidation peak current (Ipa) of ACP was increased linearly with its concentration over two linear ranges from 0.06 to 10.0 μmol L−1 and 20.0 to 80.0 μmol L−1 with a detection limit of 0.0133 μmol L−1. Due to its higher selectivity and long term stability, the composite electrode was applied to the detection of ACP in pharmaceutical formulations.
Study of the water electrolyzer with proton exchange membrane performance based on Ti current collectors charged with hydrogen
Authors: Sinyakov Matvey , Mensharapov Ruslan , Ivanov Boris , Spasov Dmitry , Zasypkina Adelina , Pak Yuri , Ivanova Nataliya 
Published: April 2024

AbstractThis work investigates the influence of hydrogen accumulation in titanium current collectors on the operating characteristics of a water electrolyzer. The investigated dependence is complex and considers the influence of both hydrogen concentration and formed titanium hydride on the characteristics of the water electrolyzer. Additionally, it takes into account the deformation of collectors and the state of their surface, which changes depending on the method of hydrogen charging from the gas phase. As the hydrogen concentration in cathode current collectors increases up to 50.2 at. %, there is a tendency for the performance of the electrolysis cell to decrease. However, the total overvoltage of the cell does not increase by more than 5 %. The transport losses of the cell are primarily affected by the hydrogen content in the current collectors. The change in morphology and structure of grains in the near‐surface layer is associated with the formation of the titanium hydride phase and the cracking of samples. The maximum increase in overvoltage for transport losses under the studied conditions was approximately 37.5 %. This effect must be considered when scaling and developing large hydrogen generation systems.
Colloidal quantum dots and two‐dimensional material heterostructures for photodetector applications
Authors: Luo Jingying , Selopal Gurpreet Singh , Tong Xin , Wang Zhiming 
Published: April 2024

AbstractPhotodetectors (PDs) are optoelectronic devices that convert optical signals into electrical responses. Recently, there has been a tremendous increase in research interest in PDs based on colloidal quantum dots (QDs) and two‐dimensional (2D) material heterostructures owing to the strong light‐absorption capacity and the well‐adjustable band gap of QDs and the superior charge carriers transfer ability of 2D materials. In particular, the heterojunction formed between QDs and 2D materials can effectively enhance the separation and transport of photogenerated charge carriers, which is expected to establish PDs with ultrahigh photoconductive gain, high responsivity, and detectivity. This review aimed to summarize the state‐of‐the‐art advances in the research of QDs/2D material nanohybrid PDs, including the device parameters, architectures, working mechanisms, and fabrication technologies. The progress of hybrid PDs based on the heterojunction of QDs with different 2D materials, along with their innovative applications, are comprehensively described. In the end, the challenges and feasible strategies in future research and development are briefly proposed.
The grain size of sediments delivered to steep debris‐flow prone channels prior to and following wildfire
Authors: Neely Alexander B. , Moon Seulgi , DiBiase Roman A. , Sklar Leonard S. , Argueta Marina O. 
Published: April 2024

AbstractDebris flows are powered by sediment supplied from steep hillslopes where soils are often patchy and interrupted by bare‐bedrock cliffs. The role of patchy soils and cliffs in supplying sediment to channels remains unclear, particularly surrounding wildfire disturbances that heighten debris‐flow hazards by increasing sediment supply to channels. Here, we examine how variation in soil cover on hillslopes affects sediment sizes in channels surrounding the 2020 El Dorado wildfire, which burned debris‐flow prone slopes in the San Bernardino Mountains, California. We focus on six headwater catchments (<0.1 km2) where hillslope sources ranged from a continuous soil mantle to 95% bare‐bedrock cliffs. At each site, we measured sediment grain size distributions at the same channel locations before and immediately following the wildfire. We compared results to a mixing model that accounts for three distinct hillslope sediment sources distinguished by local slope thresholds. We find that channel sediment in fully soil‐mantled catchments reflects hillslope soils (D50 = 0.1–0.2 cm) both before and after the wildfire. In steeper catchments with cliffs, channel sediment is consistently coarse prior to fire (D50 = 6–32 cm) and reflects bedrock fracture spacing, despite cliffs representing anywhere from 5% to 95% of the sediment source area. Following the fire, channel sediment size reduces most (5‐ to 20‐fold) in catchments where hillslope sources are predominantly soil covered but with patches of cliffs. The abrupt fining of channel sediment is thought to facilitate postfire debris‐flow initiation, and our results imply that this effect is greatest where bare‐bedrock cliffs are present but not dominant. A patchwork of bare‐bedrock cliffs is common in steeplands where hillslopes respond to channel incision by landsliding. We show how local slope thresholds applied to such terrain aid in estimating sediment supply conditions before two destructive debris flows that eventually nucleated in these study catchments in 2022.
Rock glacier distribution and kinematics in Shigar and Shayok basins based on radar and optical remote sensing
Authors: Hassan Javed , Berg Danjal Longfors , Lippert Eigil Y. H. , CHEN Xiaoqing , Hassan Wajid , Hassan Muzammil , Hussain Iqtidar , Bazai Nazir Ahmed , Khan Shfaqat A. 
Published: April 2024

AbstractRecent studies have demonstrated the rock glacier destabilisation and permafrost thawing induced by warming climate represent a continuous threat to life, infrastructure and socio‐economic development in the mountainous regions of the Hindu Kush Himalaya. This study presents the first systematic rock glacier inventory for the Shigar and Shayok basins, quantifying rock glacier geomorphology and kinematics based on morphological evidence using Google Earth images and interferometric synthetic aperture radar (InSAR). The certainty index of each inventoried rock glacier is recorded, along with its geomorphological properties and kinematic attributes. The rock glacier velocity is estimated through the InSAR time series analysis of Sentinel‐1 images from 2020 to 2021, with temporal baselines at 12‐day intervals. We developed a rock glacier inventory consisting of 84 rock glaciers covering an area of 29 km2 for the Shigar Basin and 2206 rock glaciers encompassing 369 km2 for the Shayok Basin. Among these rock glaciers, 69% and 52% are categorised as active rock glaciers, respectively. Rock glaciers in both catchments are confined to elevations between 3600 and 5875 m a.s.l., with a mean area of 0.22 km2. The maximum recorded velocity for active rock glaciers in the Shigar Basin is 101 ± 9 cm year−1, with a median of 27 ± 10 cm year−1, and in the Shayok Basin 114 ± 10 cm year−1 (median of 29 ± 9 cm year−1). Temporal variations in the surface velocities of the rock glaciers reveal that they increase with rising temperatures in both catchments, highlighting the seasonality in the rock glacier surface velocity. In total, we recorded the kinematic attributes of 98% of the inventoried rock glaciers in the study area.