bluuebunny/crossref_metadata_2025 huggingface dataset:
A Highly Efficient Conjoined‐twin Porphyrin‐based Complex for the Electrochemical Reduction of CO to Ethanol
Authors: Kour Gurpreet , Mao Xin , Du Aijun
Published: April 2021

Electrochemical conversion of carbon monoxide, a major one‐carbon product of carbon dioxide reduction, into high‐value multi‐carbon products is one of the promising strategies to address the overall energy demands and climate change. A lot of efforts have been devoted to the exploration of highly efficient catalysts for the formation of single carbon products. However, further reduction to more reduced products is hampered by high energy barriers for C−C bond formation and low selectivity of the products. Herein, the potential of homo‐bimetallic and hetero‐bimetallic complexes of previously established expanded twin porphyrin (H4L) ligand, also known as conjoined‐twin porphyrin (CTP) ligand, towards the reduction of CO to valued commodity chemicals is systematically investigated by using density functional theory (DFT) computations. In these complexes, the presence of two metal atoms in the N4 pockets enhances the chances of coupling of two adsorbed CO molecules, thus facilitating the formation of C−C bond formation. The results reveal that both the dicobalt and cobalt nickel complex of conjoined‐twin porphyrin ligand show high activity and selectivity towards the conversion of CO to ethanol with a limiting potential of only −0.59 V and −0.61 V, respectively. The narrow band gap and shallower d band centre could be attributed to the potential cause for the enhanced activity of Co containing complexes. Moreover, these complexes displayed high thermal stability, thus acts as potential candidates for experimental exploration. Our results offer a promising alternative to traditional Cu‐based electrocatalysts for the formation of C2 products.
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

Magnetic 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

Identifying 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

Using 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

Heat 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

Vascular 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

Introduction

Treatment 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.

Methods

Sexually 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.

Results

We 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).

Conclusions

GBM 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.
Pullback exponential attractors for some non‐autonomous dissipative dynamical systems
Authors: You Bo
Published: April 2021

The main objective of this paper is to develop a mathematical framework of pullback exponential attractors for some non‐autonomous dissipative dynamical systems via the ℓ‐trajectories methods. As an application, we prove the existence of pullback exponential attractors for three‐dimensional non‐autonomous planetary geostrophic equations of large‐scale ocean circulation, which implies that the fractal dimension of each section of the pullback attractor is finite.
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

This 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.
Magnetoresponsive smart nanocomposites with highly cross‐linked polymer matrix
Authors: Komarov Pavel V. , Khalatur Pavel G. , Khokhlov Alexei R.
Published: April 2021

We propose a coarse‐grained model, which is used for mesoscale simulation of nanocomposites based on a highly cross‐linked polymer network with embedded magnetic nanoparticles (MNPs) whose structure is represented as a set of connected magnetic dipoles. All the simulations are carried out with reactive dissipative particle dynamics, taking into account the interaction of MNPs with an external magnetic field. To study the effect of the spatial organization of MNPs, the network formation from polymerizing monomers is simulated both in the field and without it. Under the influence of the field, the nanoparticles are organized into filamentous aggregates that induce the anisotropic structure of the polymer matrix and affect the network topology. The stress–strain curves demonstrate that the ordering of MNPs also causes anisotropy of mechanical properties and leads to an increase in Young's modulus for uniaxial tension along the long aggregate axis. When monomers polymerize in the presence of MNPs at zero applied field, the filler particles remain disordered and Young's modulus of such a composite can exhibit a weak linear decrease with increasing filler content. This behavior is well attributed to the reduction in the number of load‐bearing chains in the simulation box. Additionally, the role of the polymer/MNP interface is studied. To this end, the corresponding interaction parameters are varied. It is found that the interface can provide an additional contribution to the tensile rigidity of composites.
Are finite‐amplitude effects important in non‐breaking mountain waves?
Authors: Metz Johnathan J. , Durran Dale R.
Published: April 2021

Linear 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

Pd 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

Lead 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

Iron‐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

In 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

Research abstract

We 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 summary

Prior 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.
Enhanced Charge Transport and Interface Passivation in Efficient Perovskite Solar Cells Using Sulfur‐Doped Graphite Carbon Nitride‐Modified SnO2‐Based Electron Transport Layers
Authors: Cao Wei , Zhang Jian , Lin Kaifeng , Qiu Lele , Li Junzhuo , Dong Yayu , Wang Jiaqi , Xia Debin , Fan Ruiqing , Yang Yulin
Published: April 2021

High‐quality electron transport layer (ETL) is beneficial to improve the charge extraction and transport, which determines the performance of perovskite solar cells (PSCs). However, the unbalanced charge extraction and interface problems commonly occur in the tin oxide (SnO2) ETL. Herein, the sulfur‐doped graphite carbon nitride (CNS) nanosheets are prepared and utilized for modifying the SnO2 ETL to fabricate high‐performance PSCs. The CNS‐modified SnO2 ETL exhibits enhanced electron mobility and conductivity, and matched energy level with perovskite, which promotes the extraction and transport of charge carriers at the interface, and balances charge extraction with the hole transport layer. In addition, interfacial carrier recombination is significantly reduced through effective interface passivation of sulfur atoms in CNS with the undercoordinated lead ions in perovskite films. Meanwhile, the introduction of an interfacial control material CNS also contributes to improve the crystalline quality of perovskite films with increasing grain size and light absorption intensity. As a consequence, an outstanding improvement in power conversion efficiency (PCE) from 18.98% to 20.33% is achieved after introducing CNS into the SnO2 ETL, as well as an enhancement in stability against humidity, retaining near 90% of the initial PCE after aging in the ambient atmosphere for 30 days.
Dual–Functional‐Polymer Dopant–Passivant Boosted Electron Transport Layer for High‐Performance Inverted Perovskite Solar Cells
Authors: Xu Rongguo , Wang Zhenfeng , Xu Wenzhan , Xu Xiuwen , Wang Jian , Hu Zhicheng , Li Yu , Wang Gaopeng , Cai Wanqing , Zheng Shizhao , Wei Guodan , Huang Fei , Yang Shihe
Published: April 2021

Herein, the use of the polymer poly([N,
N
′‐bis(2‐octyldodecyl)‐naphthalene‐1,4,5,8‐bis(dicarboximide)‐2,6‐diyl]‐alt‐5,5′‐(2,2′‐bithiophene)) (PNDI‐2T) as both a dopant in the [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) electron transport layer (ETL) of inverted perovskite solar cells (PSCs) and a surface passivant on the perovskite layer is reported. The PNDI‐2T doping is found to be crucial for improving the homogeneity of the ETL film with complete surface coverage, enhancing the electron mobility of the ETL, and promoting the energy level match between the perovskite and ETL, thereby significantly facilitating electron transport in the PSC devices. Furthermore, as a passivant, the PNDI‐2T in the ETL tends to pin on the top surface of the perovskite layer via PbS coordination. The surface passivation is also beneficial for the suppression of ion migration and diffusion of metal species from the electrodes. In consequence, PSCs with the PCBM:PNDI‐2T ETL reached an efficiency of 21.13% and retain 90% of their original performance after 860 h light soaking. This work will inspire new efforts to take advantage of multifunctional ETLs as a simple and effective method to enhance the performance and long‐term stability of PSCs.
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

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.
Effects of psilocybin microdosing on awe and aesthetic experiences: a preregistered field and lab-based study
Authors: van Elk Michiel , Fejer George , Lempe Pascal , Prochazckova Luisa , Kuchar Martin , Hajkova Katerina , Marschall Josephine
Published: April 2021

There is an increased societal trend to engage in microdosing, in which small sub-hallucinogenic amounts of psychedelics are consumed on a regular basis. Following subjective reports that microdosing enhances the experience of nature and art, in the present study we set out to study the effects of psilocybin microdosing on feelings of awe and art perception. In this preregistered combined field- and lab-based study, participants took part in a microdosing workshop after which they volunteered to self-administer a psilocybin microdose or a placebo for three consecutive weeks, while the condition was kept blind to the participants and researchers. Following a 2-week break, the condition assignment was reversed. During each block, participants visited the lab twice to measure the effects of psilocybin microdosing vs. placebo. We used standardized measures of awe, in which participants reported their experiences in response to short videos or when viewing abstract artworks from different painters. Our confirmatory analyses showed that participants felt more awe in response to videos representing funny animals and moving objects in the microdosing compared to the placebo condition. However, about two-third of our participants were breaking blind to their experimental condition. Our exploratory findings suggest that expectancy-effects may be a driving factor underlying the subjective benefits of microdosing.
Hybride Wissensarbeit
Authors: Oeste-Reiß Sarah , Bittner Eva , Cvetkovic Izabel , Günther Andreas , Leimeister Jan Marco , Memmert Lucas , Ott Anja , Sick Bernhard , Wolter Kathrin
Published: April 2021

Aufgrund der Fortschritte im Bereich der künstlichen Intelligenz (KI) ergeben sich neue Gestaltungsmöglichkeiten zur Reorganisation von Wissensarbeit an der Schnittstelle von Menschen und Maschine. Durch die Verschmelzung von menschlicher und künstlicher Intelligenz können komplementäre Stärken zum Lösen von Arbeitsaufgaben gebündelt werden. Neuartige Wissensarbeitssysteme sind erforderlich, die Wissensarbeitende sowohl bei der Ausübung von Routineaufgaben als auch Nichtroutineaufgaben unterstützen.

Der Schlagwortartikel umreißt die Grundlagen von Wissensarbeit und arbeitet die Charakteristika von Routineaufgaben und Nichtroutineaufgaben innerhalb von Arbeitsprozessen auf. Es werden Grenzen klassischer IT-gestützter Wissensarbeitssysteme als Werkzeuge umrissen, die Wissensarbeitende im Arbeitsprozess unterstützen. Aufbauend darauf diskutiert der Artikel, dass technologische Fortschritte eine arbeitsprozessintegrierte und personalisierte Unterstützung von Wissensarbeitenden erlauben. Dazu verweist der Artikel auf die Charakteristika von kollaborativ interaktiv lernenden Systemen. Darauf aufbauend werden Hybride Wissensarbeitssysteme vorgestellt, die sowohl das KI-unterstützte menschliche Lernen als auch das Mensch-unterstützte maschinelle Lernen unterstützen. In diesem Zusammenhang beschreibt der Artikel definitorische Grundlagen von menschlicher, künstlicher und hybrider Intelligenz, stellt drei Archetypen von Mensch-Maschine-Aufgaben innerhalb von hybriden Wissensarbeitssystemen vor und umreißt drei Gestaltungsdimensionen solcher Systeme. Mittels eines Praxisbeispiels zum kollaborativen Schreiben von Journalist*innen beschreibt der Artikel exemplarisch die hybride Wissensarbeit. Der Artikel schließt mit einem Ausblick auf zukünftige Forschungsbedarfe.
A biomechanical comparison of a cement-augmented odontoid screw with a posterior-instrumented fusion in geriatric patients with an odontoid fracture type IIb
Authors: Schwarz Falko , Liebsch Christian , Berger-Roscher Nikolaus , Wilke Hans-Joachim , Sakr Yasser , Kalff Rolf , Waschke Albrecht
Published: April 2021

Purpose

Possible surgical therapies for odontoid fracture type IIb include odontoid screw osteosynthesis (OG) with preservation of mobility or dorsal C1/2 fusion with restriction of cervical rotation. In order to reduce material loosening in odontoid screw osteosynthesis in patients with low bone density, augmentation at the base of the axis using bone cement has been established as a suitable alternative. In this study, we compared cement-augmented OG and C1/2 fusion according to Harms (HG).

Methods

Body donor preparations of the 1st and 2nd cervical vertebrae were randomized in 2 groups (OG vs. HG). The range of motion (ROM) was determined in 3 principle motion plains. Subsequently, a cyclic loading test was performed. The decrease in height of the specimen and the double amplitude height were determined as absolute values as an indication of screw loosening. Afterward, the ROM was determined again and loosening of the screws was measured in a computed tomography.

Results

A total of 16 were included. Two groups of 8 specimens (OG vs. HG) from patients with a median age of 80 (interquartile range (IQ) 73.5–85) years and a reduced bone density of 87.2 (IQ 71.2–104.5) mg/cc dipotassium hydrogen phosphate were examined for their biomechanical properties. Before and after exposure, the OG preparations were significantly more mobile. At the time of loading, the OG had similar loading properties to HG decrease in height of the specimen and the double amplitude height. Computed tomography revealed similar outcomes with regard to the screw loosening rate (62.5 vs. 87.5%, p = 0.586).

Conclusion

In patients with an odontoid fracture type IIb and reduced bone density, cement-augmented odontoid screw yielded similar properties in the loading tests compared to the HG. It may, therefore, be considered as a primary alternative to preserve cervical mobility in these patients.
Self-adapting data migration in the context of schema evolution in NoSQL databases
Authors: Hillenbrand Andrea , Störl Uta , Nabiyev Shamil , Klettke Meike
Published: April 2021

When NoSQL database systems are used in an agile software development setting, data model changes occur frequently and thus, data is routinely stored in different versions. The management of versioned data leads to an overhead potentially impeding the software development. Several data migration strategies exist that handle legacy data differently during data accesses, each of which can be characterized by certain advantages and disadvantages. Depending on the requirements for the software application, we evaluate and compare different migration strategies through metrics like migration costs and latency as well as precision and recall. Ideally, exactly that strategy should be selected whose characteristics fulfill service-level agreements and match the migration scenario, which depends on the query workload and the changes in the data model which imply an evolution of the database schema. In this paper, we present a methodology of self-adapting data migration, which automatically adjusts migration strategies and their parameters with respect to the migration scenario and service-level agreements, thereby contributing to the self-management of database systems and supporting agile development.
Effects of outplanting time on growth, shedding and quality of Saccharina latissima (Phaeophyceae) in its northern distribution range
Authors: Matsson Sanna , Metaxas Anna , Forbord Silje , Kristiansen Svein , Handå Aleksander , Bluhm Bodil A.
Published: April 2021

To reach the goal of large-scale seaweed cultivation in Norway and the rest of Europe, new knowledge about the commercially important kelp species Saccharina latissima is needed. Efforts to maximise biomass by outplanting the seaweed in different seasons can affect seaweed quality. Here, we investigate the effects of outplanting time (February, April, and May) when cultivating S. latissima in the northern range of the species’ distribution. We studied the quantity and quality of the seaweed biomass produced in the autumn following outplanting. Effects on quantity were evaluated as seaweed frond area, relative daily growth rate (DGR) and relative daily shedding rate (DSR). Quality was evaluated by tissue content of carbon and nitrogen compounds and number of fouling epizoans. Cultivation was successful when seedlings were outplanted in both February and April, but not in May. An earlier outplanting, in February, gave a prolonged time for grow-out at sea prior to the main recruitment event of epizoans that occurred in September, thereby earlier outplanting resulted in larger frond areas. The frond area reached in September was doubled when seedlings were outplanted in February compared to April, whereas a later outplanting in April gave a higher DGR and DSR, higher carbon content, and lower amount of fouling epizoans. The outplanting season did not affect tissue nitrate concentration or internally stored nitrate. These results show that outplanting time is an important factor to consider especially for biomass yield, but also for seaweed quality, including epibiosis of the seaweed biomass.
Alzheimer’s Disease and Epilepsy: A Perspective on the Opportunities for Overlapping Therapeutic Innovation
Authors: Lehmann Leanne , Lo Alexandria , Knox Kevin M. , Barker-Haliski Melissa
Published: April 2021

Early-onset Alzheimer’s disease (AD) is associated with variants in amyloid precursor protein (APP) and presenilin (PSEN) 1 and 2. It is increasingly recognized that patients with AD experience undiagnosed focal seizures. These AD patients with reported seizures may have worsened disease trajectory. Seizures in epilepsy can also lead to cognitive deficits, neuroinflammation, and neurodegeneration. Epilepsy is roughly three times more common in individuals aged 65 and older. Due to the numerous available antiseizure drugs (ASDs), treatment of seizures has been proposed to reduce the burden of AD. More work is needed to establish the functional impact of seizures in AD to determine whether ASDs could be a rational therapeutic strategy. The efficacy of ASDs in aged animals is not routinely studied, despite the fact that the elderly represents the fastest growing demographic with epilepsy. This leaves a particular gap in understanding the discrete pathophysiological overlap between hyperexcitability and aging, and AD more specifically. Most of our preclinical knowledge of hyperexcitability in AD has come from mouse models that overexpress APP. While these studies have been invaluable, other drivers underlie AD, e.g. PSEN2. A diversity of animal models should be more frequently integrated into the study of hyperexcitability in AD, which could be particularly beneficial to identify novel therapies. Specifically, AD-associated risk genes, in particular PSENs, altogether represent underexplored contributors to hyperexcitability. This review assesses the available studies of ASDs administration in clinical AD populations and preclinical studies with AD-associated models and offers a perspective on the opportunities for further therapeutic innovation.
Large Eddy Simulation of the By-pass Transition Process under Different Inlet Turbulence Conditions
Authors: Barsi Dario , Costa Carlo , Lengani Davide , Simoni Daniele , Ubaldi Marina
Published: April 2021

The transition process of the boundary layer developing over a flat plate with elevated inlet Free Stream Turbulence Intensity (FSTI) has been studied by means of Large Eddy Simulation (LES). To this purpose, four cases with different inflow disturbances have been tested varying the magnitude and the length scale of turbulence. LES has been performed by using the finite-volume ANSYS Fluent code. The computational domain, which was constituted by a rectangular domain with a zero thickness plate, was based on an ERCOFTAC test case in order to provide a validation with a well-known set of data by comparing the boundary layer integral parameters and mean and fluctuating streamwise velocity profiles.

The four cases were discussed within the paper by looking at classical statistical properties as well as advanced post-processing tools. It was shown that the decrease in the free stream turbulence level postpones the transition location, whereas the variation of the integral length scale has a very low influence on the distribution of the time-mean flow properties. Proper Orthogonal Decomposition (POD) has been applied to the instantaneous LES flow fields in order to provide a statistical representation of the structures responsible for transition and their response to free-stream turbulence intensity and length scale. The presence of vortical filaments parallel to the wall, typically referred as boundary layer streaks, is clearly identified; their characteristic dimensions and how they change as a function of FSTI properties were analyzed within the paper.
Performance Comparison of the Deep Learning and the Human Endoscopist for Bleeding Peptic Ulcer Disease
Authors: Yen Hsu-Heng , Wu Ping-Yu , Su Pei-Yuan , Yang Chia-Wei , Chen Yang-Yuan , Chen Mei-Fen , Lin Wen-Chen , Tsai Cheng-Lun , Lin Kang-Ping
Published: April 2021

Purpose

Management of peptic ulcer bleeding is clinically challenging. Accurate characterization of the bleeding during endoscopy is key for endoscopic therapy. This study aimed to assess whether a deep learning model can aid in the classification of bleeding peptic ulcer disease.

Methods

Endoscopic still images of patients (n = 1694) with peptic ulcer bleeding for the last 5 years were retrieved and reviewed. Overall, 2289 images were collected for deep learning model training, and 449 images were validated for the performance test. Two expert endoscopists classified the images into different classes based on their appearance. Four deep learning models, including Mobile Net V2, VGG16, Inception V4, and ResNet50, were proposed and pre-trained by ImageNet with the established convolutional neural network algorithm. A comparison of the endoscopists and trained deep learning model was performed to evaluate the model’s performance on a dataset of 449 testing images.

Results

The results first presented the performance comparisons of four deep learning models. The Mobile Net V2 presented the optimal performance of the proposal models. The Mobile Net V2 was chosen for further comparing the performance with the diagnostic results obtained by one senior and one novice endoscopists. The sensitivity and specificity were acceptable for the prediction of “normal” lesions in both 3-class and 4-class classifications. For the 3-class category, the sensitivity and specificity were 94.83% and 92.36%, respectively. For the 4-class category, the sensitivity and specificity were 95.40% and 92.70%, respectively. The interobserver agreement of the testing dataset of the model was moderate to substantial with the senior endoscopist. The accuracy of the determination of endoscopic therapy required and high-risk endoscopic therapy of the deep learning model was higher than that of the novice endoscopist.

Conclusions

In this study, the deep learning model performed better than inexperienced endoscopists. Further improvement of the model may aid in clinical decision-making during clinical practice, especially for trainee endoscopist.
Sexual dysfunctions and short-term glucose variability in young men with type 1 diabetes
Authors: Caruso Paola , Cirillo Paolo , Carbone Carla , Sarnataro Annalisa , Maiorino Maria Ida , Bellastella Giuseppe , Esposito Katherine
Published: April 2021

Purpose

Erectile dysfunction (ED) and premature ejaculation (PE) are common sexual disorders in people with diabetes. Glucose variability (GV) has been recognized as a predictor of microvascular complications. The aim of this study was to investigate the relationship between glucose variability and sexual dysfunctions in young men with type 1 diabetes.

Methods

One hundred and twelve patients with type 1 diabetes, aged 18–30 years, were enrolled. Patients were divided into two groups according to glucose variability [group 1 (high GV with coefficient of variation ≥ 36%)] and group 2 (low GV with coefficient of variation < 36%)). The presence of sexual dysfunctions was investigated with validated questionnaires.

Results

ED and PE prevalence rates in group 1 were 26% and 13%, respectively. Similarly, in group 2, the prevalence of ED was 24%, and the prevalence of PE was 13%. In both groups, no significant associations between sexual dysfunctions and parameters of glucose variability were found. Multiple regression analysis identified age and depression as independent predictors of ED and PE.

Conclusion

Young male patients affected by type 1 diabetes with high or low glucose variability show a similar prevalence of sexual dysfunctions. ED is the most common sexual dysfunction in diabetic men. Age and depression were the only independent predictive factors for sexual dysfunctions in this population.