bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneous 1H and 13C Parahydrogen‐Induced Polarization of Acetate and Pyruvate Esters
Authors: Salnikov Oleg G. , Chukanov Nikita V. , Kovtunova Larisa M. , Bukhtiyarov Valerii I. , Kovtunov Kirill V. , Shchepin Roman V. , Koptyug Igor V. , Chekmenev Eduard Y. 
Published: April 2021

AbstractMagnetic resonance imaging of [1‐13C]hyperpolarized carboxylates (most notably, [1‐13C]pyruvate) allows one to visualize abnormal metabolism in tumors and other pathologies. Herein, we investigate the efficiency of 1H and 13C hyperpolarization of acetate and pyruvate esters with ethyl, propyl and allyl alcoholic moieties using heterogeneous hydrogenation of corresponding vinyl, allyl and propargyl precursors in isotopically unlabeled and 1‐13C‐enriched forms with parahydrogen over Rh/TiO2 catalysts in methanol‐d4 and in D2O. The maximum obtained 1H polarization was 0.6±0.2 % (for propyl acetate in CD3OD), while the highest 13C polarization was 0.10±0.03 % (for ethyl acetate in CD3OD). Hyperpolarization of acetate esters surpassed that of pyruvates, while esters with a triple carbon‐carbon bond in unsaturated alcoholic moiety were less efficient as parahydrogen‐induced polarization precursors than esters with a double bond. Among the compounds studied, the maximum 1H and 13C NMR signal intensities were observed for propyl acetate. Ethyl acetate yielded slightly less intense NMR signals which were dramatically greater than those of other esters under study.
A co‐designed consumer checklist to support people with eating disorders to locate evidence‐based treatment
Authors: Wade Tracey , Calvert Shannon , Thompson Elise , Wild Cie‐ayn , Mitchison Deborah , Hay Phillipa 
Published: April 2021

AbstractIdentifying a therapist with expertise in treating eating disorders (EDs) can be a daunting process for a consumer, resulting in delayed access to evidence‐based treatment, prolonging unnecessary suffering. We developed a consumer checklist designed to empower consumers to locate evidence‐based treatment earlier. We co‐designed (researchers and people with lived experience of an ED) a 15‐item consumer checklist, for use in a meeting with a potential therapist. A survey about the checklist was sent out to people with lived experience and clinicians, seeking quantitative endorsement of each item's helpfulness in the checklist, and inviting qualitative feedback. Seventeen people with lived experience and 11 clinicians gave feedback. The items were rated as being helpful, with overlap between the two groups as to the most helpful items. Both groups rated the checklist as likely to help locate effective treatment earlier. The checklist forms a basis for a useful consumer tool in their treatment journey. Examination of its uptake and impact on outcomes for consumers seeking treatment is recommended.
One‐Step Synthesis of Core‐Shell‐Structured Mixed‐Metal CPO‐27(Cu,Co) and Investigations on Its Controlled Thermal Transformation
Authors: Bitzer Johannes , Göbel Christoph , Muhamad Ismail Ayas , Fu Qi , Muhler Martin , Kleist Wolfgang 
Published: April 2021

AbstractUsing the mixed‐metal approach, a direct synthesis route at ambient pressure was developed for a new type of bimetallic metal‐organic framework based on the CPO‐27 structure. The structural characterization of CPO‐27(Cu0.6−CS−Co0.4) using X‐ray diffraction, transmission electron microscopy, energy‐dispersive X‐ray mapping and X‐ray absorption spectroscopy revealed that the Cu2+ and Co2+ ions were exclusively incorporated at the metal positions of the CPO‐27 lattice, but with a core‐shell distribution within the crystallites. The parent framework material was then utilized as a precursor for the generation of novel bimetallic carbon‐supported materials using the controlled thermal decomposition in a reducing atmosphere. During this decomposition process, the distribution of the two metals remained the same, which resulted in unique needle‐shaped particles with a high dispersion of cobalt at the periphery of the amorphous carbon and agglomerated copper particles in the inside.
On heated surface transport of heat bearing thermal radiation and MHD Cross flow with effects of nonuniform heat sink/source and buoyancy opposing/assisting flow
Authors: Ayub Assad , Wahab Hafiz A. , Hussain Shah Syed Zahir , Shah Syed Latif , Sabir Zulqurnain , Bhatti Saira 
Published: April 2021

AbstractHeat transport subject to nonlinear thermal radiation has multiple applications in physics, industry, engineering field, and space technology, such as aerodynamic rockets, solar power technology, large open water reservoirs, and gas‐cooled nuclear reactors. This effort studies the magnetohydrodynamic flow of cross fluid, which is a type of non‐Newtonian, along a heated surface. Furthermore, the transportation of heat in the fluid is induced by thermal radiation. Furthermore, the behavior of opposing/assisting flow and impact of nonuniform heat sink/source is scrutinized. The reserved suitable transformations are carried out to shift the ruling equations into nondimensional class. Through reserved transformations, two nonlinear partial differential equations are altered into corresponding nonlinear ordinary differential equations. Then a scheme of integration referred to as Runge–Kutta–Fehlberg is imposed to get a numerical solution of these. The impact of parameters are mentioned concisely on temperature and velocity profiles in the absence and presence of a magnetic parameter. It is proved that the presence of a magnetic field steps up the velocity and temperature as well.
Nkx2‐3 induces autophagy inhibiting proliferation and migration of vascular smooth muscle cells via AMPK/mTOR signaling pathway
Authors: Zheng Huajun , Zhai Weicheng , Zhong Chongbin , Hong Qingqing , Li Hekai , Rui Bowen , Zhu Xingxing , Que Dongdong , Feng Liyun , Yu Bin , Huang Guanlin , Yin Jianlong , Li Jiacheng , Yan Jing , Yang Pingzhen 
Published: April 2021

AbstractVascular remodeling and restenosis are common complications after percutaneous coronary intervention. Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) play important roles in intimal hyperplasia‐induced vascular restenosis. NK2 Homeobox 3 (Nkx2‐3), a critical member of Nkx family, is involved in tissue differentiation and organ development. However, the role of Nkx2‐3 in VSMCs proliferation and migration remains unknown. In this study, we used carotid balloon injury model and platelet‐derived growth factor‐BB (PDGF)‐treated VSMCs as in vivo and in vitro experimental models. EdU assay and CCK‐8 assay were used to detect cell proliferation. Migration was measured by scratch test. Hematoxylin and eosin staining and immunohistochemistry staining were used to evaluate the intimal hyperplasia. The autophagy level was detected by fluorescent mRFP‐GFP‐LC3 in vitro and by transmission electron microscopy in vivo. It was shown that Nkx2‐3 was upregulated both in balloon injured carotid arteries and PDGF‐stimulated VSMCs. Adenovirus‐mediated Nkx2‐3 overexpression inhibited intimal hyperplasia after balloon injury, and suppressed VSMCs proliferation and migration induced by PDGF. Conversely, silencing of Nkx2‐3 by small interfering RNA exaggerated proliferation and migration of VSMCs. Furthermore, we found that Nkx2‐3 enhanced autophagy level, while the autophagy inhibitor 3‐MA eliminated the inhibitory effect of Nkx2‐3 on VSMCs proliferation and migration both in vivo and in vitro. Moreover, Nkx2‐3 promoted autophagy in VSMCs by activating the AMP‐activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) signaling pathway. These results demonstrated for the first time that Nkx2‐3 inhibited VSMCs proliferation and migration through AMPK/mTOR‐mediated autophagy.
Characteristics of the HIV cascade of care and unsuppressed viral load among gay, bisexual and other men who have sex with men living with HIV across Canada’s three largest cities
Authors: Moore David M , Cui Zishan , Skakoon‐Sparling Shayna , Sang Jordan , Barath Justin , Wang Lu , Lachowsky Nathan , Cox Joseph , Lambert Gilles , Noor Syed W , Grace Daniel , Jollimore Jody , Apelian Herak , Lal Allan , Parlette Abbie , Hart Trevor A 
Published: April 2021

AbstractIntroductionTreatment as prevention strategies have been variously applied across provinces in Canada. We estimated HIV care cascade indicators and correlates of unsuppressed viral load (VL) among gay, bisexual and other men who have sex with men (GBM) recruited in Vancouver, Toronto and Montreal.MethodsSexually active GBM, aged ≥16 years, were recruited through respondent‐driven sampling (RDS) from February 2017 to August 2019. Participants completed a Computer‐Assisted Self‐Interview and tests for HIV and other sexually transmitted infections (STIs). We conducted bivariate analyses comparing RDS‐adjusted proportions across cities. We used multivariable logistic regression to examine factors associated with having a measured VL ≥ 200 copies/mL with data pooled from all three cities.ResultsWe recruited 1179 participants in Montreal, 517 in Toronto and 753 in Vancouver. The RDS‐adjusted HIV prevalence was 14.2% (95% CI 11.1 to 17.2) in Montreal, 22.1% (95% CI 12.4 to 31.8) in Toronto and 20.4% (95% CI 14.5 to 26.3) in Vancouver (p < 0.001). Of participants with confirmed HIV infection, 3.3% were previously undiagnosed in Montreal, 3.2% undiagnosed in Toronto and 0.2% in Vancouver (p = 0.154). In Montreal, 87.6% of GBM living with HIV were receiving antiretroviral therapy (ART) and 10.6% had an unsuppressed VL; in Toronto, 82.6% were receiving ART and 4.0% were unsuppressed; in Vancouver, 88.5% were receiving ART and 2.6 % were unsuppressed (p < 0.001 and 0.009 respectively). Multivariable modelling demonstrated that participants in Vancouver (adjusted odds ratio [AOR]=0.23; 95% CI 0.06 to 0.82), but not Toronto (AOR = 0.27; 95% CI 0.07 to 1.03), had lower odds of unsuppressed VL, compared to Montreal, as did older participants (AOR 0.93 per year; 95% CI 0.89 to 0.97), those at high‐risk for hazardous drinking (AOR = 0.19; 95% CI 0.05 to 0.70), those with a primary care provider (AOR = 0.11; 95% CI 0.02 to 0.57), and those ever diagnosed with other STIs (AOR = 0.12; 95% CI 0.04 to 0.32).ConclusionsGBM living in Montreal, Toronto and Vancouver are highly engaged in HIV testing and treatment and all three cities have largely achieved the 90‐90‐90 targets for GBM. Nevertheless, we identified disparities which can be used to identify GBM who may require additional interventions, in particular younger men and those who are without a regular primary care provider.
Switched linear parameter‐varying tracking control for quadrotors with large attitude angles and time‐varying inertia
Authors: Nie Liang , Cai Bo , Zhu Yimin , Yang Jianan , Zhang Lixian 
Published: April 2021

AbstractThis paper is concerned with large‐angle attitude tracking control for quadrotors in the presence of time‐varying inertia and external disturbances using a switched linear parameter‐varying (LPV) system method. The attitude system of the quadrotor is divided into two parts, that is, the outer attitude‐angle loop and inner angular‐velocity loop. A feedback linearization controller is designed in the outer loop to generate the desired angular velocities. In the inner loop, the nonlinear quadrotor dynamics with time‐varying inertia is approximated by a switched LPV system that consists of a series of LPV models. The persistent dwell time (PDT) switching logic is adopted to describe the fast and slow switches coexist among these LPV models. Then, both the continuous‐time state‐feedback and dynamic output‐feedback controllers are designed, which ensure the globally uniformly asymptotically stability and external disturbance attenuation performance of the attitude tracking error system. Finally, the effectiveness of the proposed tracking control method of quadrotors is validated with an example.
Are finite‐amplitude effects important in non‐breaking mountain waves?
Authors: Metz Johnathan J. , Durran Dale R. 
Published: April 2021

AbstractLinear theory has long been used to study mountain waves and has been successful in describing much of their behaviour. In the simplest theoretical context, that of two‐dimensional steady‐state flow with constant Brunt–Väisälä frequency (N) and horizontal wind speed (U), finite‐amplitude effects are relatively minor until wave breaking occurs. However, in more complex environmental profiles, significant finite‐amplitude effects occur below the wave‐breaking threshold. We constructed a linearized version of a fully nonlinear time‐dependent model, thereby facilitating direct comparisons between linear and finite‐amplitude solutions in cases with upstream profiles representative of typical real‐world events. Beginning with the simplest profile that includes a tropopause, namely an environment with constant upstream wind speed and two layers of constant static stability, we progressively investigate more complex profiles that include vertical wind shear typical of the midlatitude westerlies. Our results demonstrate that, even without wave breaking, finite‐amplitude effects can play an important role in modulating the mountain‐wave amplitude and gravity‐wave drag. The modulation is a function of the tropopause height and is most pronounced when the cross‐ridge flow increases strongly with height.
Elucidation of the Active Phase in Pd‐Based Catalysts Supporting on Octahedral CeO2 for Low‐Temperature Methane Oxidation
Authors: Wu Mingwei , Li Wenzhi , Zhang Xia , Xue Fengyang , Yang Tao , Yuan Liang 
Published: April 2021

AbstractPd catalysts supported on CeO2 (Pd/CeO2) are highly active towards lean methane combustion, and the catalytic behavior is substantially affected by the chemical property of surface palladium species. In this work, various Pd catalysts supported on octahedral‐CeO2 (Pd/O‐CeO2) were successfully prepared by redox interation‐engaged strategy. The oxidation state of palladium species was controlled by varying the calcination condition. X‐ray absorption characterization coupled with light‐off curves confirmed that the catalytic activity of relevant catalysts was closely related with the proportion of the metallic Pd and PdO species. Within limits, increasing Pd0/PdO ratio can bring superior catalytic behavior and the approximately equal ratio of interfacial hybrid Pd0/PdO phase exhibits the optimal catalytic activity. Importantly, in situ DRIFTS results demonstrated that the hybrid Pd0/PdO phase was recognized as the active site pair for lean methane oxidation, which is attributed to the fact that the metallic Pd0 species can adsorb and dissociate methane molecules and then the resulting intermediate species further react with the active O* of PdO, which thereby promotes CH4 activation.
Dual‐Ligand Functionalized Ag2S Quantum Dots for Turn‐On Detection of Lead (II) Ions in Mineral Samples Based on Aggregation‐Induced Enhanced Emission
Authors: Cheng Shasha , Hou Dongyan , Li Chen , Liu Shu , Zhang Cuiling , Kong Qianqian , Ye Mingqiang , Wu Shan , Xian Yuezhong 
Published: April 2021

AbstractLead ion (Pb2+) is considered as one of the most toxic elements because it damages human health and pollutes the environment. Therefore, it is of great significance to develop convenient assays for the detection of Pb2+ with high sensitivity. A simple fluorescent probe for selective Pb2+ sensing based on silver sulfide quantum dots (Ag2S QDs) was developed in this work. The Ag2S QDs with excellent fluorescence properties were synthesized without the need of oxygen‐free condition. In the presence of Pb2+, the coordination between Pb2+ with glutathione ligand modified on Ag2S QDs could enhance the signal intensity of Ag2S QDs via aggregation induced enhanced emission (AIEE). Thus, the Pb2+ sensor was successfully developed based on a fluorescence turn‐on mechanism. The Pb2+ sensor shows a linear detection range from 0.05–20.0 μM, and the detection limit is down to 15.5 nM. Furthermore, the constructed assay have been successfully applied for the detection of Pb2+ in the mineral samples. The sensing system for Pb2+ detection based 3‐MPA/GSH‐Ag2S QDs has outstanding advantages, including fast response, high sensitivity, and easy operation. Therefore, it shows great potential in environmental detection.
Iron‐Catalyzed N‐Alkylation of Secondary Amines with Alcohols Using Borrowing Hydrogen Strategy
Authors: Qu Ruxin , Cheng Yaxuan , Yang Siwei , Zhao Chaoyu , Liu Huiling , Huang Xuri 
Published: April 2021

AbstractIron‐based catalysts have been widely used in N‐alkylation of amines with alcohol using borrowing hydrogen strategy, due to low toxicity and cost. Herein, based on Saito and co‐workers’ experiment, we discuss a possible mechanism for N‐alkylation of secondary amines with alcohol under an iron‐based catalyst using DFT calculations. Contrary to N‐alkylation of primary amines, only one hydrogen on alcohol benzyl group is taken by the iron‐catalyst during radical transfer process. Thus, instead of forming an imine, a structure with a radical is formed. Overall, there are three parts to this mechanism: 1) hydrogen borrowing by the iron‐based catalyst; 2) radical addition; 3) hydrogen reduction. There are two possible pathways of hydrogen borrowing: either by a distal oxygen or by the oxygen directly coordinating with iron. According to the computed free energy barrier, the former one is more favorable. We also found four possible pathways of radical addition. Our calculations suggest a direct dehydration step with short steps and lower energy barrier was more favorable.
Cu(II)‐Catalyzed Synthesis of 2,3,6‐Trisubstituted Pyridines from Saturated Ketone and Alkynones/1,3‐Dicarbonyl Compounds
Authors: Zhan Zhen Z. , He Jian P. , Jiang Peng B. , Zhang Ming M. , Wang He S. , Luo Nan , Huang Guo S. 
Published: April 2021

AbstractIn this work, a highly efficient one‐pot synthesis of 2,3,6‐trisubstituted pyridines has been achieved through copper‐catalyzed saturated ketones and alkynones/1,3‐dicarbonyl compounds. This method provided the convenient routes to the synthesis of 2,3,6‐trisubstituted pyridines with good functional group tolerance. Compared with previous works, this method does not require the synthesis of enamine in advance.
Follow the smoke: The pollution haven effect on global sourcing
Authors: Berry Heather , Kaul Aseem , Lee Narae 
Published: April 2021

AbstractResearch abstractWe examine whether and how foreign environmental standards influence global sourcing decisions. Taking a question‐driven approach, we find a negative association between the stringency of a country's environmental standards and its share in US imports for 82 manufacturing industries across 77 countries between 2006 and 2016. This pollution haven effect holds not only for sourcing from owned foreign operations (offshore integration), but also for sourcing from unrelated third parties abroad (offshore outsourcing), and is stronger in industries with high toxic emissions and low technological intensity. These results are robust across alternative measures of environmental stringency and to using the Kyoto Agreement as an instrumental variable. These findings shed new light on how firms use global sourcing, and especially offshore outsourcing, to arbitrage across institutional environments.Managerial summaryPrior work has shown that multinational firms prefer to locate their plants in countries with weak environmental standards: the so‐called Pollution Haven Effect. We extend this research to show that firms not only source from countries with weak environmental standards from their own plants, but also from third‐party foreign suppliers. Using Census data on US manufacturing imports from 77 countries between 2006 and 2016 we show that when the stringency of environmental standards in a country decreased, sourcing from that country increased, and that this effect was just as strong for sourcing from third parties as from owned operations. Our study thus suggests that previous work may have substantially underestimated the pollution haven effect, by focusing on owned global sourcing rather than all global sourcing.
String fragmentation in supercooled confinement and implications for dark matter
Authors: Baldes Iason , Gouttenoire Yann , Sala Filippo 
Published: April 2021

Abstract
A strongly-coupled sector can feature a supercooled confinement transition in the early universe. We point out that, when fundamental quanta of the strong sector are swept into expanding bubbles of the confined phase, the distance between them is large compared to the confinement scale. We suggest a modelling of the subsequent dynamics and find that the flux linking the fundamental quanta deforms and stretches towards the wall, producing an enhanced number of composite states upon string fragmentation. The composite states are highly boosted in the plasma frame, which leads to additional particle production through the subsequent deep inelastic scattering. We study the consequences for the abundance and energetics of particles in the universe and for bubble-wall Lorentz factors. This opens several new avenues of investigation, which we begin to explore here, showing that the composite dark matter relic density is affected by many orders of magnitude.
Early morbidity and dose–volume effects in definitive radiochemotherapy for locally advanced cervical cancer: a prospective cohort study covering modern treatment techniques
Authors: Seppenwoolde Yvette , Majercakova Katarina , Buschmann Martin , Dörr Elke , Sturdza Alina E. , Schmid Maximilian P. , Pötter Richard , Georg Dietmar 
Published: April 2021

Abstract
Purpose
Predicting morbidity for patients with locally advanced cervix cancer after external beam radiotherapy (EBRT) based on dose–volume parameters remains an unresolved issue in definitive radiochemotherapy. The aim of this prospective study was to correlate patient characteristics and dose–volume parameters to various early morbidity endpoints for different EBRT techniques, including volumetric modulated arc therapy (VMAT) and adaptive radiotherapy (ART).

Methods and materials
The study population consisted of 48 patients diagnosed with locally advanced cervix cancer, treated with definitive radiochemotherapy including image-guided adaptive brachytherapy (IGABT). Multiple questionnaires (CTCAE 4.03, QLQ-C30 and EORTC QLQ-CX24) were assessed prospectively for patients treated with different EBRT techniques, including online adaptive VMAT. Contouring and treatment planning was based on the EMBRACE protocols. Acute toxicity, classified as general, gastrointestinal (GI) or genitourinary (GU) and their corresponding dose–volume histograms (DVHs) were first correlated by applying least absolute shrinkage and selection operator (LASSO) and subsequently evaluated by multiple logistic binomial regression.

Results
The treated EBRT volumes varied for the different techniques with ~2500 cm3 for 3D conformal radiotherapy (3D-CRT), ~2000 cm3 for EMBRACE‑I VMAT, and ~1800 cm3 for EMBRACE-II VMAT and ART. In general, a worsening of symptoms during the first 5 treatment weeks and recovery afterwards was observed. Dose–volume parameters significantly correlating with stool urgency, rectal and urinary incontinence were as follows: bowel V40Gy < 250 cm3, rectum V40Gy < 80% and bladder V40Gy < 80–90%.

Conclusion
This prospective study demonstrated the impact of EBRT treatment techniques in combination with chemotherapy on early morbidity. Dose–volume effects for dysuria, urinary incontinence, stool urgency, diarrhea, rectal bleeding, rectal incontinence and weight loss were found.