bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carbofluorination of π‐Bonds and Related Reactions Involving Tandem C−C/C−F Bond Formation
Authors: McKnight E. Ali , Cadwallader Dusty , Le Christine M. 
Published: April 2023

AbstractDue to the unique properties of C−F bonds, organofluorine compounds occupy a privileged space in the pharmaceutical, agrochemical, and polymer industries. Carbofluorination reactions involve the formation of a C−C and a C−F bond, typically across a π‐bond or another unsaturated functionality that is revealed upon in situ activation. The design of tailored substrates and new catalyst systems has enabled carbofluorination chemistry to emerge as a promising manifold for the synthesis of unique fluorinated scaffolds. This review covers the application of nucleophilic and electrophilic fluorinating reagents in this chemistry, in addition to recently developed atom‐economical carbofluorination reactions using organofluorine compounds as dual reagents.
Simulation‐based methodology to identify damage indicators and safety thresholds for post‐earthquake evaluation of structures
Authors: Galvis Francisco A. , Hulsey Anne M. , Baker Jack W. , Deierlein Gregory G. 
Published: April 2023

AbstractAfter a strong earthquake, criteria are needed to determine whether buildings are safe to reoccupy based on observable damage. This paper presents a simulation‐based methodology to identify relevant damage indicators and safety thresholds for building structures. Prior knowledge of the most relevant damage indicators and their thresholds can increase the accuracy and confidence of post‐earthquake evaluations. Current practice to translate observable damage into a tagging decision relies on qualitative guidelines based on past earthquake experience and judgment, which may be susceptible to speculation and interpretation. In addition, past experience may not be relevant to newer structural systems and to large or complex (e.g., high‐rise) buildings. To augment past observations and data from structural component tests, nonlinear dynamic analyses can be used to estimate the collapse safety of structures with simulated damage. Technologies to execute these simulations have matured over the years, although to date they have not been systematically applied to evaluate the destabilizing effects of simulated damage on collapse safety. In this paper, a methodology is presented to use numerical simulations of damage to identify and evaluate relevant damage indicators that can be quantitatively related to safety thresholds. Damage indicators are selected based on their reliability in estimating the structural safety and their sensitivity to modeling uncertainty, that is, where the preferred indicators are insensitive to variability in the structural materials and model parameters. The safety threshold for each damage indicator is selected to maximize accuracy in post‐earthquake building assessments. The methodology is demonstrated through an application study of ductile reinforced concrete frame buildings. Results show that aggregated indices of structural component damage (e.g., aggregated over the floor of a building) outperform other damage indicators based on peak or residual drifts or simpler percentages of damaged components. Subject to agreement of a number underlying assumptions, this methodology can be applied to a wider variety of structures to improve post‐earthquake evaluation guidelines.
Investigation of buried karst sinkholes under a bog using ground penetrating radar (GPR) and electrical resistivity tomography (ERT)
Authors: Džeriņš Peteris , Karušs Jānis , Lamsters Kristaps , Ješkins Jurijs , Ķelpe Artūrs 
Published: April 2023

AbstractActive evaporite karst processes in the Baltic states are associated with a few relatively small regions where gypsum rocks can be found close to the Earth's surface. One of these areas lies in the vicinity of the Pandu bog. However, such a possibly active karst region, which is covered by peat and in which the mapping of karst formations is complex, has not been previously investigated. In this study, we present a buried and peat‐filled karst cover‐collapse sinkhole mapping approach that involves a combination of ground‐penetrating radar (GPR), electrical resistivity tomography (ERT) and conventional boreholes. A detailed map of the bog's substratum topography was constructed from a geophysical surveying dataset. It reveals 15 distinctly expressed sinkholes with diameters of several tens of metres. Overall, 140 potential sinkholes were also mapped using remote sensing data in the vicinity of the bog. Higher electrical resistivity anomalies were identified inside the peat; they coincide with scatter‐free zones in GPR data and water layers in boreholes. Highly disturbed internal peat layering was also detected in these sinkholes. It is suggested that these water layers and disturbed peat layering may have formed due to the subsidence of the lower peat layers, and thus they represent relatively younger sinkholes. This is also supported by evidence from orthophoto maps, which showed the formation and disappearance of surficial lakes and depressions on the bog surface. Our results revealed the presence of active and widespread karst processes under the bog that have not been previously noticed despite the fact that they have implications for the assessment of geohazards in this area.
Antioxidant activity and total phenolic compounds of Commiphora gileadensis extracts obtained by ultrasonic‐assisted extraction, with monitoring antiaging and cytotoxicity activities
Authors: Ahmed Hani , Rashed Marwan M. A. , Almoiliqy Marwan , Abdalla Mohammed , Bashari Mohanad , Zaky Mohamed Y. , Hailin Zhu , Naji Taha A. A. , Eibaid Ahmed , Wang Jinpeng , Jiang Li‐Ping 
Published: April 2023

AbstractCommiphora gileadensis (C. gileadensis) has been identified and linked with various health benefits and pharmaceutical potential for its phytochemical activities and chemical constituents. This study aimed to evaluate ultrasonic‐assisted extraction (USE) technique for total phenols content from C. gileadensis leaf compared to the hydrodistillation extraction (HDE). Our results showed that the USE operating conditions were identified as: MeOH·H2O solvent‐to‐fresh sample ratio of 80:20 (v/v); ultrasonic power/frequency at 150 W/20 kHz; and a temperature of 40 ± 1°C; subjected to acoustic waves intermittently for a calculated time (5 min) during the total programmed time of 12 min. The USE exhibited (118.71 ± 0.009 mg GAE/g DM) more amounts of all phenols than HDE (101.47 ± 0.005 mg GAE/g DM), and antioxidant (77.78 ± 0.73%, 75.27 ± 0.59% scavenging inhibition of DPPH), respectively. Anti‐aging and Cytotoxicity activities were investigated. The results of biological evaluations showed that the crude extracts of C. gileadensis significantly extended the replicative lifespan of K6001 yeast. In addition, in vitro cytotoxicity against the HepG2 cell line showed significant anticancer activity, and approximately 100 μg/mL is required to decrease viability compared with that of the control. This study is proven for a larger scale to extract and isolate compounds of C. gileadensis for potential utilization in the pharmaceutical industry. In conclusion, advanced methods afford an extract with high activity in the biological properties of the extract.
Evaluating robust determinants of the WTI/Brent oil price differential: A dynamic model averaging analysis
Authors: Filippidis Michail , Filis George , Magkonis Georgios , Tzouvanas Panagiotis 
Published: April 2023

AbstractWe investigate the robust determinants of the West Texas Intermediate/Brent oil price differential by employing a time‐varying framework. To achieve this, a dynamic model averaging framework is used, considering monthly data over the period 1994:1–2021:3. Our results suggest that the convenience yield, the global economic activity index, and the government bond yields act as the main factors that exercise a persistent and significant impact, for the largest part of the study period, although at different magnitude. More importantly, though, we show that at different time periods there are additional factors that exercise a significant impact on the oil price differential, such as refining constraints, stock market volatility, trading volume, and geopolitical risk. Thus, unless a dynamic modeling framework is employed, the full spectrum of the related effects cannot be revealed. A series of tests confirm the robustness of our findings. Several policy implications of these results are also discussed.
Differential activity of transcription factor Sox9 in early and adult oligodendroglial progenitor cells
Authors: Hassel Lisa A. , Fröb Franziska , Küspert Melanie , Hillgärtner Simone , Arnold Philipp , Huang Wenhui , Kirchhoff Frank , Wegner Michael 
Published: April 2023

AbstractThe high‐mobility‐group domain‐containing transcription factor Sox9 confers glial competence to neuroepithelial precursors in the developing central nervous system and is an important determinant of astroglial and oligodendroglial specification. In oligodendroglial cells, it remains expressed in oligodendrocyte progenitor cells (OPCs) of the developing nervous system, but is shut off in differentiating oligodendrocytes as well as in OPCs that persist in the adult nervous system. To better understand the role of Sox9 in OPCs, we generated mouse models that allowed oligodendroglial expression of a Sox9 transgene during development or in the adult. With transgene expression beginning in the last trimester of pregnancy, the number of OPCs increased dramatically, followed by comparable gains in the number of pre‐myelinating and myelinating oligodendrocytes as assessed by marker gene expression. This argues that Sox9 boosts oligodendrogenesis during ontogenetic development at all stages, including terminal oligodendrocyte differentiation. When Sox9 transgene expression started in the adult, many transgene‐expressing OPCs failed to maintain their progenitor cell identity and instead converted into myelinating oligodendrocytes. As infrequent and inefficient differentiation of adult OPCs is one of the main obstacles to effective remyelination in demyelinating diseases such as Multiple Sclerosis, increased Sox9 levels in adult OPCs may substantially increase their remyelination capacity.
Prevalence of congenital heart disease according to the echocardiography findings in 8145 neonates, multicenter study in southern Iran
Authors: Parvar Seyedeh Yasamin , Ghaderpanah Rezvan , Naghshzan Amir 
Published: April 2023

AbstractIntroductionCongenital heart disease (CHD), the lethal congenital anomaly in newborns, is multifactorial, with environmental and genetic factors contributing to its occurrence. Although some studies on the prevalence of CHD have been conducted throughout the country, this large‐scale study aims to provide information on the prevalence of various types of CHDs in newborns according to the echocardiography findings.Patients and MethodsOver 3 years, 8145 neonates with suspected CHD who underwent echocardiography by a trained pediatric cardiologist were included in this multicenter, cross‐sectional observational study. CHD was categorized into two major groups; cyanotic and acyanotic heart disease. The SPSS version 22 software was used to analyze the data with a significance level set at 0.05.ResultsOf 8145 neonates who were referred to our centers with CHD symptoms, 6307 were indicated for echocardiography. The mean age of the studied population was 8.5 ± 9.3 days and the male‐to‐female ratio was 2.6, especially in the arterial septal defect (ASD), ventricular septal defect (VSD), and patent ductus arteriosus (PDA) groups. 77.2% of patients had acyanotic heart disease (100 in 1000 neonates) with ASD as the most common one and 9% were diagnosed with cyanotic heart disease (11 in 1000 neonates) with transposition of the great arteries as the most common form and the aortopulmonary window was the rarest form.ConclusionThis large prospective, multicenter screening study reported arterial septal defect (85%) and patents with ductus arteriosus (32%) as the most frequent type of CHD. Moreover, the prevalence of male patients was significantly higher. This information would be helpful for health policy makers, stakeholders, and general practitioners in regions where there are no trained pediatric cardiologist fellowships and limited access to echocardiography devices for better management of CHD.
Population Pharmacokinetics of Anlotinib, a Multiple Receptor Tyrosine Kinase Inhibitor, in Chinese Patients With Malignant Tumors
Authors: Xu Gaoqi , Yang Dihong , Shu Qi , Zhu Junfeng , Ding Haiying , Xin Wenxiu , Zhong Like , Zhu Liqin , Fang Luo 
Published: April 2023

AbstractThe objective of this study was to investigate the pharmacokinetic behavior of anlotinib in Chinese patients with malignant tumors using the population approach. A total of 407 anlotinib plasma concentrations from 16 patients were analyzed in this study. Anlotinib was administered orally 12 or 16 mg in the single‐dose phase and 12 mg once daily in the multiple‐dose phase. A population pharmacokinetic model was established using nonlinear mixed‐effects model method. The potential influence of demographic and pathophysiological factors on oral anlotinib pharmacokinetics was investigated in a covariate analysis. The final model was evaluated using goodness‐of‐fit plots, visual predictive check, and bootstrap methods. The pharmacokinetic profile of anlotinib was best described by a 1‐compartment model with first‐order absorption and first‐order elimination. The population estimates of the apparent total clearance, apparent volume of distribution, and absorption rate constant were 8.91 L/h, 1950 L, and 0.745/h, respectively. Body weight was identified as a significant covariate on apparent volume of distribution. Patients with low body weight tended to show higher exposure to anlotinib than those with high body weight. However, these differences were not clinically significant based on the simulations of the individual body weight effects. Taken together, this population pharmacokinetic model adequately described the pharmacokinetics of anlotinib in patients with malignant tumors and supports the same starting dose among them.
Australian graduate radiographers' perspectives and experiences of work readiness
Authors: Zhang Julie , Makanjee Chandra , Hayre Christopher M. , Lewis Shantel 
Published: April 2023

AbstractIntroductionGraduate radiographers entering their qualified positions need to orientate and familiarise themselves with a rapidly changing work environment to deliver a high standard of diagnostic imaging services. During this transitional phase, these newcomers also strive to meet self‐expectations and workplace expectations. This study was performed to understand the work readiness perspectives and initial experiences of graduate radiographers on beginning their newly qualified roles.MethodsThe study used a qualitative phenomenological approach to collect data through individual semi‐structured in‐depth telephone interviews with 14 purposively sampled undergraduate and postgraduate radiographers. The rich data were transcribed verbatim and then thematically analysed.ResultsFour major themes emerged: (1) preparing to be ‘work‐ready’, (2) initial encounters as qualified radiographers, (3) personal and professional challenges and (4) support strategies and advice for new graduates.ConclusionsNew graduate radiographers face many personal and professional challenges but agree that they thrive in supportive collegial environments. Most participants had a high perspective of their work readiness strongly related to their clinical placements as students, workplace familiarity, support networks and coping strategies. Further review into individual workplace orientations by organisation leaders may benefit the immersion and enhancement of graduate radiographers' initial experiences in their new role.
Coordinated framework for active distribution system planning integrating active system management schemes
Authors: Sannigrahi Surajit , Ghatak Sriparna Roy , Acharjee Parimal 
Published: April 2023

AbstractTo counter different technical challenges with large‐scale renewable energy sources (RESs) integration, distribution systems (DS) are recently undergoing the transition process from passive to active DS (ADS), which has introduced further complications for system planning. In such context, this study proposes an ADS expansion planning (ADSEP) framework in coordination with active system management (ASM) schemes. A multi‐stage ADSEP model, unlike the traditional single‐stage model, is designed where the planning horizon is divided into several stages to make the planning investments gradually. For proper coordination of different planning alternatives, an effective bi‐level model is formulated based on upper‐level and lower‐level planning. In accordance with recent energy market scenario, RESs are assumed to be invested by RES Investor (RESI) and to ensure the desired financial benefits of RESI, the Distribution Company (DISCOM) offers bus‐wise contract price (BCP) for purchasing RESs generated energy. Moreover, a computationally efficient 2 m point estimate method (PEM) is applied to model the uncertainties of load and RESs. The proposed planning framework with multiple objectives is solved using the multi‐objective PSO technique considering 69‐bus test system.
Nanoattapulgite reduces the stimulation effect of nitrogen fertilizer on ammonia‐oxidizing microorganisms in salinized fluvo‐aquic soil
Authors: Li Hongqiang , Yao Rongjiang , Gao Qiancheng , Liu Yuxing , Yang Jingsong , Wang Xiangping , Xie Wenping , Zhang Xing 
Published: April 2023

AbstractThe nitrification, which utilized ammonium nitrogen (NH4+‐N) as substrate, is susceptible to the bioavailability of NH4+‐N. However, it is unclear how the nitrification process responds to the decrease of NH4+‐N availability due to nanoattipulgite (NA) addition, especially in salt‐affected soils. A pot experiment was performed to study the effect of different NA rates (NA0, NA1, and NA2: 0, 25, 50 g kg−1) and nitrogen fertilizer (F) gradients (F1, F2, and F3: 54, 81, 108 mg N kg−1) on the net nitrification rate (NNR), abundance of ammonia monooxygenase (amoA) gene copies, and communities of ammonia‐oxidizing archaea (AOA) and bacteria (AOB) in a moderately salinized fluvo‐aquic soil. The concentrations of NH4+‐N and nitrate nitrogen in soils showed insignificant differences among various NA treatments. The addition of NA reduced NNR after topdressing but had no significant effect on NNR after base fertilizer. Nitrogen fertilizer could decrease the amoA gene abundance of AOA and increase the amoA gene abundance of AOB in soil. NA could maintain the relative stability of AOB amoA gene abundance. NA treatment only changed the community composition of AOB before topdressing at the F2 level but did not change the community composition of ammonia‐oxidizing microorganisms under other conditions. Overall, NA adsorbs more NH4+‐N and indirectly affects nitrification by reducing the stimulating effect of F on the activity of ammonia‐oxidizing microorganisms, which can play an important role in reducing nitrate pollution and denitrification loss from saline soil.
General Simulation Method for Quantum‐Sensing Systems
Authors: Riexinger Felix , Kutas Mirco , Haase Björn , Bortz Michael , von Freymann Georg 
Published: April 2023

AbstractQuantum sensing encompasses highly promising techniques with diverse applications including noise‐reduced imaging, super‐resolution microscopy, as well as imaging and spectroscopy in challenging spectral ranges. These detection schemes use biphoton correlations to surpass classical limits or transfer information to different spectral ranges. Theoretical analysis is mostly confined to idealized conditions. Therefore, theoretical predictions and experimental results for the performance of quantum‐sensing systems often diverge. This general simulation method that includes experimental imperfections bridges the gap between theory and experiment. A theoretical approach is developed and the capabilities are demonstrated with the simulation of aligned and misaligned quantum‐imaging experiments. The results recreate the characteristics of the experimental data. The simulation results were further used to improve the obtained images in post‐processing. As a simulation method for general quantum‐sensing systems, this work provides a step toward powerful simulation tools for interactively exploring the design space and optimizing the experiment's characteristics.
Sub‐THz 3D printed lens based on diffractive neural network for low‐cost detection of orbital angular momentum states
Authors: Cheng Fangxiao , Li Yan , Deng Li , Yang Yang , Yin Liang 
Published: April 2023

AbstractAccurate detection of orbital angular momentum (OAM) is one of the critical techniques for OAM‐related communications. However, conventional OAM identification approaches are often complicated and costly. In this letter, a convenient method based on diffraction neural network (DNN) is presented for OAM states detection in the sub‐terahertz (sub‐THz) regime. The optimal phase distribution of the lens for OAM state detection is obtained from DNN training. Then, a prototype based on three‐dimensional printing is fabricated according to the training results. Numerical simulation and experiment are performed at 140 GHz to verify the proposed approach. The results show that the proposed method can accurately detect the OAM state with lower complexity. This convenient detection approach can provide a novel pathway for realizing low‐cost THz OAM receiving systems, promoting the development of future communication technology.
A hydro‐mechanically‐coupled XFEM model for the injection‐induced evolution of multiple fractures
Authors: Wang Yuxiao , Javadi Akbar A. , Fidelibus Corrado 
Published: April 2023

AbstractIn this paper, a two‐dimensional eXtended Finite Element Method (XFEM) solution is presented for the hydro‐mechanically coupled hydro‐frac‐induced propagation of multiple fractures in rocks. Fractures are considered one‐dimensional objects, and the rock matrix is regarded as a two‐dimensional medium. Rules for improving the accuracy of the solution are included to deal with the transfer of variables between fractures and matrix in the coupling process. The main variables include fluid pressure and fracture aperture. The following assumptions are made: (1) the fluid pressure inside a fracture is applied as a net pressure; (2) fluid leak‐off is ignored; (3) the fluid front is regarded as a fracture front provided that the area of fluid lag has a small effect on fracture propagation compared to the area at which the fluid pressure is applied. The fluid flow is governed by the lubrication equation, while the XFEM is used to describe the behaviour of the elastic medium. The simulation results are compared with analytical solutions for a single hydraulic fracture model to verify and validate the proposed algorithm. A simulation with multiple hydraulic fractures is also performed to investigate the interference effect of multiple fractures and fracture propagation. The shadow effect caused by multiple fractures is analysed to manifest the stress variation along the propagation path.