bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of (−)‐(R)‐Sitagliptin by RhI‐Catalyzed Asymmetric Hydroamination
Authors: Berthold Dino , Breit Bernhard 
Published: September 2021

AbstractWe report of a concise synthesis of (R)‐sitagliptin monophosphate – a drug predominantly applied in the treatment of type 2 diabetes. Utilizing our recently developed RhI‐catalyzed hydroamination of allenes for the stereoselective construction of the inherent chiral amino function, a new approach to (R)‐sitagliptin monophosphate on a 3.5 mmol scale was established.
Continuous Flow Organocatalytic Chlorination of Alkenes
Authors: Iordanidis Nicolaos S. , Zografos Alexandros L. , Gallos John K. , Koftis Theocharis V. , Stathakis Christos I. 
Published: September 2021

AbstractA regioselective anti‐dichlorination and allylic chlorination of isolated double bonds is described. Such chlorination reactions benefit from a combination of methyl phenyl sulfoxide and TMSCl. The method has been appropriately adjusted to fit the continuous flow technology requirements, aiming to a broader industrial implementation for the synthesis of pharmaceutically important compounds. Towards the same direction, a catalytic protocol has been developed, using sub‐stoichiometric amount of sulfoxide and environmentally friendly H2O2 as the stoichiometric oxidant, with comparable efficacy.
An Overview of Antifouling Strategies for Electrochemical Analysis
Authors: Zhou Lin , Li Xinru , Zhu Boyu , Su Bin 
Published: September 2021

AbstractFouling is a key issue which limits the practical applications of electrochemical sensors (ECSens) in both in vitro and in vivo analysis. The analytical sensitivity, limit of detection (LOD), selectivity, reproducibility and life‐time of ECSens are all greatly affected by fouling. Although numerous methods and materials have been developed to minimize the fouling effect in past several decades, not all of them are suitable for constructing antifouling ECSens. In this paper we present an overview of surface antifouling strategies for ECSens. We begin with a short summary of sources and impacts of fouling under both in vitro and in vivo environments. Then the current surface antifouling strategies for ECSens are discussed, including self‐assembled monolayers (SAMs), antifouling polymers, porous coating, in‐situ electrochemical and photocatalytic cleaning. The antifouling mechanisms, advantages and challenges of each strategy are briefly summarized. The article ends up with a short conclusion and perspectives. We hope this article is helpful for constructing and designing ECSens with both outstanding antifouling performance and electrochemical activity for electrochemical analysis.
Measuring multi‐volatility states of financial markets based on multifractal clustering model
Authors: Huang Xun , Tang Huiyue 
Published: September 2021

AbstractMeasuring multi‐volatility states is an important component of financial risk management. In this paper, taking 17 years' high‐frequency data of the Shanghai Stock Exchange Composite Index (SSEC) as an example, we set out to propose a novel model of multifractal clustering model (MCM), combining multifractal algorithm with k‐mean clustering algorithm, to measure the multi‐volatility states of financial markets. The empirical results present that the financial markets are multifractal and the multifractal parameter Sα measured by multifractal algorithm correlates well with the performance of financial markets. Meanwhile, the multi‐volatility states recognized by k‐mean clustering algorithm based on Sα have obvious statistical significance. More importantly, the experiment results show that by the loss functions and Diebold–Mariano (DM) test, generalized autoregressive conditional heteroscedasticity (GARCH) model with the multi‐volatility state measured by MCM is superior to others measured by Markov switching (MRS) model and hidden Markov model (HMM) as well as that without the multi‐volatility states, which indicates that MCM has best performance of measuring the multi‐volatility states of financial markets. The robustness of MCM is also  evaluated by Shenzhen Securities Component Index (SZSE) instance set, SSEC instance sets with different time intervals, and different volatility models. The results still prove that MCM has strong robustness on measuring the multi‐volatility states of financial markets.
Ni migration in solid oxide cell electrodes: Review and revised hypothesis
Authors: Mogensen Mogens B. , Chen Ming , Frandsen Henrik Lund , Graves Christopher , Hauch Anne , Hendriksen Peter Vang , Jacobsen Torben , Jensen Søren Højgaard , Skafte Theis Løye , Sun Xiufu 
Published: September 2021

AbstractSevere degradation of Ni‐YSZ (yttria stabilized zirconia) electrodes of solid oxide cells (SOCs) due to Ni migration is well known, but the literature contains apparent contradictions. The mechanisms are still under debate. Fine structured Ni‐YSZ composite electrodes often degrade at operation temperature (700–950°C), because Ni particles lose electrical contact with each other as larger Ni‐particles grow on the expense of smaller ones. Another type of Ni migration, which may be very damaging, is the relocation of Ni in the most active part of the Ni‐YSZ cermet electrode next to the dense YSZ electrolyte. Emphasis is put on the migration of Ni away from the YSZ electrolyte in solid oxide electrolysis cells (SOECs). This is seen as an important obstacle to the commercialization of SOC systems.Apart from temperature, degradation of Ni‐YSZ electrodes in SOCs is related to Ni‐YSZ electrode overpotential and the local redox potential of the gas mixture inside the porous Ni‐YSZ electrode. A unifying Ni migration mechanism is proposed, and methods of alleviating the electrode degradation are discussed. The hypothesis is that Ni migrates via surface diffusion of Ni(OH)x species below ca. 800°C and via Ni(OH)x species in gas phase above ca. 900°C.
Horizontalverspannung nicht bindiger Böden durch die Rütteldruckverdichtung mit Tiefenrüttler – Experimentelle und numerische Untersuchungen
Authors: Gasser Daniel , Marte Roman , Tschuchnigg Franz 
Published: September 2021

AbstractVibrationsverdichtungsverfahren zur tief reichenden Verbesserung nicht bindiger Böden werden seit den 1930er‐Jahren eingesetzt. Verwendet werden entweder Tiefenrüttler oder Aufsatzrüttler. Die Planung der Verdichtungsmaßnahme wie auch die anschließende Qualitätskontrolle erfolgt bis heute fast ausschließlich auf der Grundlage von empirischen Zusammenhängen. Diesbezüglich hat sich der Einsatz von indirekten Untergrunderkundungsmethoden wie z. B. Ramm‐ oder Drucksondierungen und die arbeitsbegleitende Aufzeichnung von Verfahrensparametern etabliert.Im gegenständlichen Beitrag werden experimentelle Untersuchungen zur Erfassung der Horizontalverspannung im Untergrund in der Folge von Rütteldruckverdichtung mit Tiefenrüttler vorgestellt, um Grundlagen für das bessere Verständnis der Steifigkeits‐ und Festigkeitserhöhung verbesserter, nicht bindiger Böden zu erlangen. Des Weiteren werden in verkürzter Form Ergebnisse einer stark vereinfachten numerischen Simulation zur Abschätzung der Verspannung diskutiert.Es wurde ein großmaßstäblicher Verdichtungsversuch realisiert. An zwei Versuchsfeldern mit unterschiedlichem Verdichtungsraster kam neben herkömmlichen Methoden zur Erfassung des Verdichtungserfolgs (Ramm‐ und Drucksondierungen) das Inklinodeformeter erstmals für diesen Anwendungsfall zum Einsatz. Neben dem qualitativen Verlauf der Verspannung über die Tiefe konnte auch der Einfluss des Verdichtungsrasterabstands messtechnisch aufgezeichnet werden.
Products of an Early Cretaceous extensional mechanism in the central Great Xing'an Range: Felsic plutons in the Zhalantun area and their parental magma compositions and diagenetic processes
Authors: Huang Xiao , Guo Rong‐Rong , Li Zong‐Hui , Yan Ming , Sun Bao‐Liang 
Published: September 2021

Late Mesozoic extensional mechanisms in the Great Xing'an Range (GXR) and relevant crust–mantle interactions are complicated, which result in widespread magmatisms with diverse parental origins and petrogenesises. In this paper, we present the lithology, whole‐rock geochemistry, and zircon U–Pb–Lu–Hf isotopes for granodiorite‐monzogranite rocks (GM) and their enclaves of quartz monzodiorites in the Zhalantun area, east of central GXR. Zircon U–Pb dating results reveal that both GM rocks and their enclaves of quartz monzodiorites yield a nearly identical crystallization age of ~125 Ma. The GM rocks exhibit weak peraluminous and high‐K calc‐alkaline compositions with high SiO2, Na2O + K2O, and Al2O3 contents, and low MgO, Mg#, Fe2O3T, and TiO2 contents, which are characterized by fractionated REE patterns, relatively strong negative Eu anomalies, enrichments of LILEs (e.g., Rb, Ba, and K), and depletions of Nb, Ta, P, and Ti. The parental origins for GM samples were juvenile crustal materials, with positive zircon εHf(t) values of +2.5 to +12.9. The whole‐rock and zircon geochemical simulations limit slightly lower GM magma crystallization temperatures (TTi‐Zrn) of 683–824°C and relatively more oxidizing conditions (log(fO2) = FMQ+7.6–FMQ‐6.8), and further confine that they were probably formed by ~10–35% degrees of fluid‐present partial melting of lower to middle crustal materials, with fractional crystallization and/or residual mineral phases of plagioclase, amphibole, clinopyroxene, and garnet. By contrast, the enclaves of quartz monzodiorites possess lower SiO2 and Na2O + K2O compositions, but higher MgO, Mg#, Fe2O3T, and TiO2 values, which are consistent with metaluminous–weak peraluminous and high‐K calc‐alkaline series. All quartz monzodiorites exhibit sub‐parallel right‐declined REE patterns, negligible to none Eu anomalies, enrichments of LILEs, and depletions of Nb, Ta, and Ti. Combined with mineral morphology and disequilibrium structures, the whole‐rock geochemical and Hf isotopic simulations imply that parental magmas for quartz monzodiorites were hybrid mixtures between ~50% host GM acid magmas and ~50% ancient crust compositions, with a wide range of zircon εHf(t) of +14.0 to −7.7, slightly higher TTi‐Zrn of 710–835°C, and lower log(fO2) of FMQ+8.2–FMQ‐10.5. Taken together, felsic plutons in the Zhalantun area correspond to an episode of extensional mechanism‐related crust–mantle interactions, which might be induced by either the Mongol‐Okhotsk domain or Palaeo‐Pacific tectonic domain, or both of them.
Depositional age and provenance analysis of the Wufoshan Group in the southern North China Craton: Constraints from detrital zircon U–Pb geochronology and Hf isotopes
Authors: Li Zhensheng , Jiang Rourou , Cao Gaoshe , Ma Xueting , Zhang Jiaodong , Zhang Yan , Jia Chao 
Published: September 2021

The Late Precambrian Wufoshan Group from the southern North China Craton (NCC) is significant for its contribution to our understanding of the Precambrian evolution of the NCC, which consists of the Lower Ma'anshan, Upper Ma'anshan, Puyu, Luotuopan, and Hejiazhai formations. Detrital zircon U–Pb ages and Lu–Hf isotopes from the Puyu, Luotuopan, and Hejiazhai formations are used in this study to constrain the depositional age and provenance of the Wufoshan Group and crustal evolution of the NCC. The Puyu Formation is characterized by detrital zircon U–Pb age populations of ~2.13 Ga and ~2.50 Ga, similar to the Lower–Upper Ma'anshan formations from the literature. The Luotuopan Formation exhibits age populations of 1.85–2.18 Ga and 2.28–2.98 Ga, with mainly negative εHf(t) values and scattered positive εHf(t) values clustering at two groups of 2.48–2.52 Ga and 2.64–2.97 Ga. The Hejiazhai Formation displays age populations of 0.98–2.00 Ga and 2.51–2.79 Ga with mainly positive εHf(t) values, whose depositional age is constrained as Neoproterozoic era by the youngest graphical detrital zircon age of 976 ± 20 Ma. Provenance studies indicate that the Mesoproterozoic Lower–Upper Ma'anshan and Puyu formations were sourced from the middle Trans‐North China Orogen (TNCO), while the Neoproterozoic Luotuopan and Hejiazhai formations were derived from the southern TNCO and the North Qinling Terrane, respectively. The clastic rock series in the southern NCC is divided into Luotuopan type and Hejiazhai type by detrital zircon U–Pb age pattern and Hf isotopic characteristics, suggesting Late Mesoarchean to Early Palaeoproterozoic (2.47–2.97 Ga) crustal growth in the interior NCC, and Late Palaeoproterozoic to Early Neoproterozoic (0.98–2.08 Ga) crustal growth in the marginal NCC. The crustal evolution of the NCC can be classified into three stages, namely >3.0 Ga continental nuclei generation, the Meso‐Neoarchean massive growth, and the Palaeo‐Mesoproterozoic interior reworking and marginal growth.
Speech pathology service enhancement for people with head and neck cancer living in rural areas: Using a concept mapping approach to inform service change
Authors: Foley Jasmine , Ward Elizabeth C. , Burns Clare L. , Nund Rebecca L. , Wishart Laurelie , Graham Nicky , Patterson Corey , Ashley Amy , Fink Julie , Tiavaasue Emily , Comben Wendy 
Published: September 2021

AbstractBackgroundSpeech pathology (SP) services provide swallowing and communication intervention to people with head and neck cancer (HNC) across the continuum of care. However, difficulties exist with access and delivery of services in rural areas. The study aim was to identify actionable goals for SP change, utilizing a concept mapping approach.MethodsEleven SP staff from two regional/remote services completed the concept mapping process. Multivariate analysis and multidimensional scaling were used to develop a final set of prioritized goals for change.ResultsBetween the two participating health services, 30 actionable goals were identified within the “green‐zone” on the go‐zone graph of importance and changeability. Among the most highly rated areas for change was the need to deliver and receive more support for training, mentoring, and supervision to consolidate skills.ConclusionsThis methodology enabled identification of prioritized, actionable changes to improve SP services for people with HNC living in regional/remote areas.
Agua Salud project experimental catchments hydrometric data, Panama
Authors: Regina Jason A. , Ogden Fred L. , Hall Jefferson S. , Stallard Robert F. 
Published: September 2021

AbstractThe Smithsonian Tropical Research Institute (STRI) instrumented the Agua Salud (AS) Experimental Catchments as part of an ongoing series of land‐cover related experiments in the steep, saprolitic, lowland, seasonal tropics of central Panama. The sites include tree plantations, rotational grazed pastures, native forests from 10 to over 80 years old, and a monoculture grassland. This data note provides a brief description of the instrumented catchments, rainfall and discharge data collection methods, data processing, and online availability.
Geomorphology and vegetation drive hydrochemistry changes in two Northeast Greenland streams
Authors: Pastor Ada , Skovsholt Louis J. , Christoffersen Kirsten S. , Wu Naicheng , Riis Tenna 
Published: September 2021

AbstractClimate change is causing drastic landscape changes in the Arctic, but how these changes modify stream biogeochemistry is not clear yet. We examined how catchment properties influence stream nitrogen (N) and dissolved organic carbon concentrations (DOC) in a high‐Arctic environment. We sampled two contrasting headwater streams (10–15 stations over 4.8 and 6.8 km, respectively) in Northeast Greenland (74°N). We characterized the geomorphology (i.e., bedrock, solifluction and alluvial types) and the vegetation (i.e., barren, fell field, grassland and tundra types) cover of each subcatchment area draining into each sampling station and collected water samples for hydrochemistry characterization. The two sampled streams differed in geomorphology and vegetation cover in the catchment. Aucellaelv catchment was mostly covered by a ‘bedrock’ geomorphology (71%) and ‘fellfield’ vegetation (51%), whereas Kæerelv was mostly covered by ‘alluvial’ geomorphology (65%) and ‘grassland’ and ‘tundra’ vegetation (42% and 41% respectively). Hydrochemistry also differed between the two study streams, with higher concentrations of inorganic N forms in Aucellaelv and lower DOC concentrations, compared to Kærelv. The results from the linear mixed model selection showed that vegetation and geomorphology had contrasting effects on stream hydrochemistry. Subcatchments with higher solifluction sheets and limited vegetation had higher nitrate concentrations but lower DOC concentrations. Interestingly, we also found high variability on the production and removal of nitrate across subcatchments. These results indicate landscape controls to nutrient and organic matter exports via flow paths, soil organic matter stocks and nutrient retention via terrestrial vegetation. Moreover, the results suggest that climate change induced alterations to vegetation cover and soil physical disturbance in high‐Arctic catchments will affect stream hydrochemistry, with potential effects in stream productivity, trophic relations as well as change of solute export to downstream coastal areas.
Factors accelerating agricultural innovation and sustainability: The case of paddy farmers
Authors: Aydoğan Mehmet , Demiryürek Kürşat , Özer Osman Orkan , Uysal Osman 
Published: September 2021

Abstract
The primary purpose of this study is to reveal the factors accelerating both the innovativeness and sustainability levels of paddy farmers. The data used in the study were obtained from the questionnaires conducted with 70 paddy farmers in the Bafra district of Samsun province, Turkey, determined by a simple random sampling method. Paddy farmers were divided into three groups as low, medium, and high innovativeness groups with hierarchical cluster analysis. An ANOVA was used to compare the socioeconomic and farming characteristics of the paddy farmers, and accelerated failure time models were used to analyze the factors affecting the innovativeness and sustainability variables. The research results indicated that the number of years of formal education, the agricultural experience, the amount of labor per unit area, the animal assets, the share of agricultural income in the total income, the number of memberships to farmer organizations, paddy production area, sustainable agriculture area, and cooperation scores differed from the innovativeness groups. The farmers' collaboration in agricultural activities increased the likelihood that they are an innovator. The results concluded that the number of years of formal education, global good agriculture practice, agricultural experience, household size, animal assets, and women's employment influenced both the innovativeness and sustainability variables. Encouraging the participation of women in agricultural production in rural areas, including sustainability-related issues in addition to technical issues in farmer training programs, and ensuring the participation of women in such training are issues that should be considered in future. Integr Environ Assess Manag 2022;18:824–835. © 2021 SETAC
KEY POINTS
The organization and increased cooperation between farmers increase innovativeness. Innovative farmers are more sustainable than non-innovative farmers. The participation of women in farm activities positively affects agricultural sustainability and innovation. The agricultural innovations raise sustainability.
Ovarian function following use of various hemostatic techniques during treatment for unilateral endometrioma: A randomized controlled trial
Authors: Araujo Raquel Silveira da Cunha , Maia Sabina Bastos , Baracat Clara Micalli Ferruzzi , Fernandes Clarissa Queiroz Bezerra de Araujo , Ribeiro Helizabet Salomão Abdalla Ayroza , Ribeiro Paulo Augusto Ayroza Galvão 
Published: September 2021

AbstractObjectiveTo compare the effect of hemostatic techniques (bipolar energy versus hemostatic sealants versus suture) on the ovarian reserve of patients submitted to laparoscopic cystectomy for the surgical excision of unilateral endometrioma.MethodsA randomized controlled trial conducted in a teaching hospital included 84 patients with unilateral endometrioma. The patients underwent laparoscopic stripping for excision of the unilateral endometrioma between March 2018 and February 2020. Three different hemostatic techniques—bipolar energy (Group 1), hemostatic sealants (Group 2), and suture (Group 3)—were compared. Anti‐Müllerian hormone (AMH) levels were measured before, and 1 and 6 months after surgery to determine changes in ovarian function.ResultsFollowing surgery, AMH levels decreased in all the groups; however, this decrease was not statistically significant. Comparison between groups showed no statistically significant differences in AMH levels between the three hemostatic techniques used. Six months after surgery, median AMH levels were: 1.65 ng/mL (interquartile range [IQR] 0.62–2.08 ng/mL) in Group 1, 1.87 ng/mL (IQR 1.27–2.97 ng/mL) in Group 2, and 1.53 ng/mL (IQR 1.18–2.44 ng/mL) in Group 3.ConclusionThe present study suggests that there is no difference between the different hemostatic techniques used in laparoscopic cystectomy for the treatment of unilateral endometriomas.Registered at ClinicalTrials.gov: NCT03430609.
https://clinicaltrials.gov/ct2/show/NCT03430609
Negative histology in surgically managed tubal ectopic pregnancy
Authors: Shehab Qasem J. , Dolloway Lucasta , Damra Amal M. , Al Zoubi Mazhar S. , Albeitawi Soha N. 
Published: September 2021

AbstractObjectiveTo determine the rate of negative histology following salpingectomy for suspected ectopic pregnancy.MethodsA retrospective case series in a university hospital in the southwest of England was carried out. The records of all patients who had a salpingectomy for suspected ectopic pregnancy between January 2007 and December 2012 were reviewed. The primary outcome was the histology result.ResultsIn total, 359 salpingectomies were performed for suspected ectopic pregnancy over 6 years. On histologic examination, 4.7% of fallopian tubes did not have evidence of an implantation site or trophoblastic tissue. When the macroscopic appearance of the fallopian tube was correlated with the surgical findings (e.g., rupture with large hemoperitoneum) and follow‐up notes were reviewed thoroughly, the histology of 0.84% of all salpingectomies was not consistent with a tubal ectopic pregnancy.ConclusionsTrue negative histology for surgically managed ectopic pregnancy is less than 1%.