bluuebunny/crossref_metadata_2025 huggingface dataset:
Natural Radionuclide Analysis on Crude Petroleum from Some Oil Fields in Ghana
Authors: Gafrey Calvin Kwesi , Wilson Robert , Amoako George , Anderson Benjamin
Published: November 2021

The petroleum industries benefit immensely from developing scientific processes and procedures that determine characteristics of crude oils and distinct them. This is because crude oils are acquired from various geological sources and each sedimentary rock has its own distinct chemical properties that affect extraction, refinery and environmental safety. Extraction of crude oils may result in exposure of some radionuclide elements from sedimentary rocks into the environments. This nuclear exposure may affect lives and can cause ecological imbalance. Applications of gamma emission spectroscopy has grown rapidly around the world because of its accurate measurement and precision. Such technique has not been applied for the study of naturally occurring radionuclide materials (NORMs) in crude oils from the active oil fields in Ghana. The study employed the use of gamma spectroscopic technique for characterization of crude oil samples from Jubilee Oil Field, Tweneboa Enyenra Ntomme (TEN) Oil Field and Saltpond Oil Field. The technique was applied on four crude oil samples. The results of this paper actually report on radionuclide concentrations of naturally occurring radioactive materials in four crude samples using a Gamma-Ray spectrometer. Three radionuclides, radium-226 (226 Ra), thorium-232 (232 Th) and potassium-40 (40 K), were identified from each crude sample (JF, TF SF-1 and SF-2). It was observed that samples from Saltpond Oil Field estimated the highest activity concentration and the least was crude oil from Jubilee Oil Field. The activity concentration values were far less than the approved values by International Atomic Energy Agency for basic safety standard. Therefore, the radionuclides activity concentration values of crude oil samples from Jubilee, TEN, and Saltpond oil fields were within the basic safety standards exemption levels of the International Atomic Energy Agency (IAEA). The crude oils from the oil fields can therefore be considered safe to handle. Also, the results of the activity concentrations from the sample used for this study indicate that crude petroleum from the oil fields may relatively have little nuclear activity impact to ecology and human health. The result of this study may be adopted by the Environmental Protection Agency and the Petroleum Stakeholders of Ghana for development of petroleum geo-radionuclides radiation safety measures.
FERIDAS ABERTAS: NARCISISMO DAS PEQUENAS DIFERENÇAS, REPETIÇÃO E MEMÓRIA
Authors: Alves Lucas de Oliveira
Published: November 2021

Esse artigo propõe-se a refletir sobre o conceito freudiano de narcisismo das pequenas diferenças, pensado a partir da amarração dos registros lacanianos de real, simbólico e imaginário, e sua incidência nas relações sociais brasileiras em diferentes tempos. Parte-se da discussão do conceito na teoria psicanalítica, para na sequência, em diálogo com teóricos como Walter Benjamin e Giorgio Agamben, refletir sobre a repetição, assim como sobre relevância da memória para a percepção de nossos sintomas sociais. Discorre-se sobre como alguns discursos apropriam-se da imagem das diferenças para perpetrar e resgatar lógicas de opressão, desigualdade e sobre o modo como o resgate da memória, articulada a uma possibilidade de elaboração, pode ensejar diferentes modos de se relacionar na pólis e lidar com as diferenças.
A PSICANÁLISE NA TORMENTA - PSICANALISTAS BRASILEIROS TESTEMUNHAM
Authors: Oliveira Luiz Eduardo Prado de , Douville Olivier
Published: November 2021

Existem alguns testemunhos sobre o impacto da ascensão do fascismo na prática da psicanálise e sobre as reflexões dos grupos de intelectuais a ela ligados. Raramente estiveram tão atrelados à tormenta quanto estes aqui. Como os psicanalistas em sua clínica reagem ao impacto desse discurso de ódio tão violento? E aqueles que são alvos desse discurso, os negros, os homossexuais, entre outros? Sabemos que o ódio visa a eliminar tudo o que lhe escapa, sendo ele é exclusão máxima. Apresentamos aqui algumas respostas de psicanalistas e amigos brasileiros a esses questionamentos.
TESTEMUNHAS DO (DES)ENCONTRO: NOTAS PSICANALÍTICAS SOBRE O AMOR EM “FLORES AZUIS” DE CAROLA SAAVEDRA
Authors: Teixeira Leonia Cavalcante , Maia Mariana Ferreira
Published: November 2021

Este artigo objetiva discutir o amor na obra literária “Flores Azuis”, de Carola Saavedra, articulando-o a noção psicanalítica acerca do amor a partir de Freud e Lacan. O diálogo entre Literatura e Psicanálise visa a apreensão da experiência subjetiva do amor e de um possível desdobramento seu na figura de um sofrimento oriundo do desenlace amoroso. Privilegiou-se a modalidade amor-paixão (Verliebtheit), na qual se busca a plenitude a partir de uma negação da castração. As relações entre Literatura e Psicanálise são tematizadas, bem como a contextualização da obra de Carola Saavedra no cenário da literatura contemporânea, na qual o epistolar e o amor são ressaltados. A perda do objeto amado, ao remeter ao estado de desamparo, reafirma, de forma contundente e através do próprio amor, aquilo que as personagens buscavam negar amando: a castração de si e do Outro.
ABISMOS INOMINÁVEIS E NOVAÇÃO: QUESTÕES SOBRE O FINAL DE ANÁLISE
Authors: Leite Sonia
Published: November 2021

Freud em "Análise terminável e interminável" indica que ao final de uma análise encontra-se um rochedo, o insuperável rochedo da castração, tanto para as mulheres como para os homens.  Lacan, por sua vez, fala da presença de uma pedra no caminho em direção ao final da análise, encontro do real que, ao contrário de Freud, considera passível de ser transposto.  A travessia da fantasia supõe, assim, o embaraço diante da crueza de algo que se apresenta como intransponível.  Encontro com o inominável que comporta duas facetas: por um lado, o silenciamento do sujeito , diante do traumático e, por outro, aquilo que, incitando o ultrapassamento do plano das identificações, permite o aparecimento de um sentido novo, de uma novação. Uma nova-ação que afirma um paradoxo que demanda a invenção ao final de cada experiência analítica e que compromete o sujeito com a transmissão daquilo que é essencial à psicanálise.
LES RYTHMES DE L'EXISTENCE
Authors: Vendier Véronique
Published: November 2021

Cet article esquisse l'itinéraire de reconquête des rythmes de l'existence. Partant d'un constat, l'existence est en fait rythmée mais ces rythmes sont le plus souvent passivement subis et ne sont pas ceux choisis par le sujet, nous nous demandons comment retrouver une maîtrise de ces rythmes car cette maîtrise est une condition pour vivre mieux, sinon pour bien vivre. De l'écoute du corps, mis en péril par la rupture d'une maladie, en passant par la contrainte de règles rigides, nous verrons que l'issue se situe dans la création de rythmes propres.
ARTICULAÇÕES ENTRE PSICANÁLISE E MÚSICA: A PRESENÇA DA VOZ NA CONSTITUIÇÃO DO SUJEITO
Authors: Viana Beatriz Alves , Pieri Luciana Carvalho
Published: November 2021

O trabalho articula psicanálise e música, buscando refletir como a dimensão da musicalidade está presente na constituição do sujeito. Considera-se que, primordialmente, a voz materna – através de uma construção sonora por meio de sua fala carregada de jogos fonéticos e ritmos – transmite ao Infans o convite para tornar-se sujeito e poder, assim, compor sua própria música singular. Para tanto, utilizaremos algumas contribuições teóricas do campo da música – que concebem esta última enquanto uma linguagem – visando pensar sobre as primeiras experiências sonoras vinculadas à musicalidade que existe desde os primeiros meses de vida. Estas nos servirão de subsídios para pensar como a musicalidade da voz materna transmite a linguagem que inicialmente se inscreve para além da significação, uma vez que o bebê antes de ter acesso à dimensão da significação capta e registra o que há de material na voz.
Prediction and comparison of postural discomfort based on MLP and quadratic regression
Authors: Lee Jinwon , Hwang Jaejin , Lee Kyung-Sun
Published: November 2021

Objective

The objective of this study was to predict postural discomfort based on the deep learning-based regression (multilayer perceptron [MLP] model).

Methods

A total of 95 participants performed 45 different static postures as a combination of 3 neck angles, 5 trunk angles, and 3 knee angles and rated the whole-body discomfort. Two different combinations of variables including model 1 (all variables: gender, height, weight, exercise, body segment angles) and model 2 (gender, body segment angles) were tested. The MLP regression and a conventional regression (quadratic regression) were both conducted, and the performance was compared.

Results

In the overall regression analysis, the quadratic regression showed better performance than the MLP regression. For the postural discomfort group-specific analysis, MLP regression showed greater performance than the quadratic regression especially in the high postural discomfort group. The MLP regression also showed better performance in predicting postural discomfort among individuals who had a variability of subjective rating among different postures compared to the quadratic regression. The deep learning for postural discomfort prediction would be useful for the efficient job risk assessment for various industries that involve prolonged static postures.

Conclusions

The deep learning for postural discomfort prediction would be useful for the efficient job risk assessment for various industries that involve prolonged static postures. This information would be meaningful as basic research data to study in predicting psychophysical data in ergonomics.
Boosting Piezoelectricity under Illumination via the Bulk Photovoltaic Effect and the Schottky Barrier Effect in BiFeO3
Authors: Heo Yooun , Alexe Marin
Published: November 2021

Piezoelectricity is a key functionality induced by conversion between mechanical and electrical energy. Enhancement of piezoelectricity in ferroelectrics often has been realized by complicated synthetical approaches to host unique structural boundaries, so‐called morphotropic phase boundaries. While structural approaches are well‐known, enhancing piezoelectricity by external stimuli has yet to be clearly explored, despite their advantages of offering not only simple and in situ control without any prior processing requirement, but compatibility with other functionalities. Here, it is shown that light is a powerful control parameter to enhance the piezoelectric property of BiFeO3 single crystals. A series of measurements based on piezoresponse force microscopy and conductive atomic force microscopy, under illumination, reveal a locally enhanced effective piezoelectric coefficient, dzz, eventually showing almost a sevenfold increase. This phenomenon is explained with theoretical models by introducing the two main underlying mechanisms attributed to the bulk photovoltaic effect and Schottky barrier effect, involving the role of open‐circuit voltage and photocharge carrier density. These results provide key insights to light‐induced piezoelectricity enhancement, offering its potential for multifunctional optoelectronic devices.
Black Mesoporous TiO2 Nanoparticles for Enhancing Surface Assisted Laser Desorption and Ionization in Mass Spectrum Analysis
Authors: Chang Wenya , Ouyang Xueliang , Zhong Huan , Liu Daoxue , Deng Dawei , Xie Zhuoying
Published: November 2021

Surface assisted laser desorption ionization mass spectrometry (SALDI‐MS) is a powerful analytical technology for the high‐throughput detection of metabolites, drugs, and other bioactive molecules. The performance of SALDI‐MS in enhancing molecules desorption and ionization mainly depends on the surface properties of matrix utilized. Here, black titanium dioxide (B‐TiO2) nanoparticle is used for the first time as a novel matrix for enhancing laser desorption and ionization (LDI) and demonstrates significant advantages over white titanium dioxide (W‐TiO2). Further, the black mesoporous TiO2 coated Fe3O4 magnetic nanoparticles (B‐mTiO2 MNPs) are designed and prepared, which possess a high molar absorption coefficient, strong magnetic response, higher specific surface area, and ample phosphorylation binding sites. The B‐mTiO2 MNPs exhibit a superior ionization efficiency, low background signal, and good reproducibility (RSD < 10%) in the analysis of compounds with different molecular weights and practical bio‐sample. Salt tolerance of B‐mTiO2 MNPs up to 10 mm PBS, meanwhile, B‐mTiO2 MNPs also provides excellent enrichment efficiency for phosphopeptides (the detection limit low to 5 × 10−10 M).
Ultra‐Fast and In‐Depth Reconstruction of Transition Metal Fluorides in Electrocatalytic Hydrogen Evolution Processes
Authors: Ji Pengxia , Yu Ruohan , Wang Pengyan , Pan Xuelei , Jin Huihui , Zheng Deyong , Chen Ding , Zhu Jiawei , Pu Zonghua , Wu Jinsong , Mu Shichun
Published: November 2021

Hitherto, there are almost no reports on the complete reconstruction in hydrogen evolution reaction (HER). Herein, the authors develop a new type of reconfigurable fluoride (such as CoF2) pre‐catalysts, with ultra‐fast and in‐depth self‐reconstruction, substantially promoting HER activity. By experiments and density functional theory (DFT) calculations, the unique surface structure of fluorides, alkaline electrolyte and bias voltage are identified as key factors for complete reconstruction during HER. The enrichment of F atoms on surface of fluorides provides the feasibility of spontaneous and continuous reconstruction. The alkaline electrolyte triggers rapid F− leaching and supplies an immediate complement of OH− to form amorphous α‐Co(OH)2 which rapidly transforms into β‐Co(OH)2. The bias voltage promotes amorphous crystallization and accelerates the reconstruction process. These endow the generation of mono‐component and crystalline β‐Co(OH)2 with a loose and defective structure, leading to an ultra‐low overpotential of 54 mV at 10 mA cm−2 and super long‐term stability exceeding that of Pt/C. Moreover, DFT calculations confirm that F− leaching optimizes hydrogen and water adsorption energies, boosting HER kinetics. Impressively, the self‐reconstruction is also applicable to other non‐noble transition metal fluorides. The work builds the fundamental comprehension of complete self‐reconstruction during HER and provides a new perspective to conceive advanced catalysts.
Releasable AlGaN/GaN 2D Electron Gas Heterostructure Membranes for Flexible Wide‐Bandgap Electronics
Authors: Zhang Yi‐Yu , An Shu , Zheng Yixiong , Lai Junyu , Seo Jung‐Hun , Lee Kwang Hong , Kim Munho
Published: November 2021

The development of transferrable free‐standing semiconductor materials and their heterogeneous integration to arbitrary substrates open up new possibilities in improving device performance, exploring nonconventional manufacturing approaches, and offering a pathway to soft, conformal, and flexible electronics. In this work, flexible AlGaN/GaN high‐electron mobility transistors (HEMTs) are demonstrated, which are transfer‐printed from AlGaN/GaN on insulator to a flexible substrate using a novel releasing strategy based on the fast, facile, and reliable transfer process. Flexible AlGaN/GaN HEMTs possess good electrical performance such as the maximum saturated drain current density and transconductance of 110 mA mm−1 and 42.5 mS mm−1, respectively. Moreover, a significant piezoelectric behavior is observed when the device is under strain, resulting from the piezoelectric‐induced polarization at the heterostructure interface. Owing to an additional strain‐induced piezoelectric effect by the mechanical bending, the performance of AlGaN/GaN HEMT can be further improved. The results demonstrate that the device has great potential in applications for the next‐generation flexible electronics, such as wearable systems, intelligent microinductor systems, and smart systems that can sense or feedback external mechanical stimuli.
Highly Stable Forming‐Free Bipolar Resistive Switching in Cu Layer Stacked Amorphous Carbon Oxide: Transition between CC Bonding Complexes
Authors: Hyeon Da Seul , Jang Gabriel , Min SunHwa , Hong Jin Pyo
Published: November 2021

Recent advances in resistive switching devices have garnered a considerable amount of interest as an alternative option for next‐generation nonvolatile memories due to their distinct advantages of ultralow power consumption, fast operation, and outstanding scaling potential. Among the recently considered active media, amorphous carbon oxide (α‐C:Ox) shows promise in terms of device performance, essentially due to the transition between carbon sp2–sp3 complex under bias. However, widespread utilization of this media still remains a challenge due to its undesirable high forming voltage and insufficient stability issues. Here, a simple approach to stack a suitable Cu layer at the α‐C:Ox layer/W interface of simple Pt/α‐C:O/W frames is introduced to engineer resistive switching characteristics. Precise control of a stacked Cu layer (2.5 nm thick) identifies numerous benefits of forming‐free characteristics, reliable switching time, and appreciably stable features compared with those of single α‐C:Ox active medium. The possible principle underlying the experimental findings is described based on the oxygen ion drift‐driven transition between sp2 and sp3 bonds at the intermixed regions of α‐C:Ox/Cu interfaces under bias, which are systematically confirmed by structural observations.
Device Performance of Emerging Photovoltaic Materials (Version 2)
Authors: Almora Osbel , Baran Derya , Bazan Guillermo C. , Berger Christian , Cabrera Carlos I. , Catchpole Kylie R. , Erten‐Ela Sule , Guo Fei , Hauch Jens , Ho‐Baillie Anita W. Y. , Jacobsson T. Jesper , Janssen Rene A. J. , Kirchartz Thomas , Kopidakis Nikos , Li Yongfang , Loi Maria A. , Lunt Richard R. , Mathew Xavier , McGehee Michael D. , Min Jie , Mitzi David B. , Nazeeruddin Mohammad K. , Nelson Jenny , Nogueira Ana F. , Paetzold Ulrich W. , Park Nam‐Gyu , Rand Barry P. , Rau Uwe , Snaith Henry J. , Unger Eva , Vaillant‐Roca Lídice , Yip Hin‐Lap , Brabec Christoph J.
Published: November 2021

Following the 1st release of the “Emerging photovoltaic (PV) reports”, the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer‐reviewed articles in academic journals since August 2020. Updated graphs, tables, and analyses are provided with several performance parameters, e.g., power conversion efficiency, open‐circuit voltage, short‐circuit current density, fill factor, light utilization efficiency, and stability test energy yield. These parameters are presented as a function of the photovoltaic bandgap energy and the average visible transmittance for each technology and application and are put into perspective using, e.g., the detailed balance efficiency limit. The 2nd instalment of the “Emerging PV reports” extends the scope toward tandem solar cells and presents the current state‐of‐the‐art in tandem solar cell performance for various material combinations.
Sheared Thick‐Film Electrode Materials Containing Silver Powders with Nanoscale Surface Asperities Improve Solar Cell Performance
Authors: Hilali Mohamed M. , Pal Shweta , More Rishabh V. , Saive Rebecca , Ardekani Arezoo M.
Published: November 2021

Thick‐film screen‐printed fine‐line metallization is one of the most important process steps in the whole production chain of photovoltaic cell manufacturing as variations in industrial solar cell performance mainly depend on electrode properties. The impact of Ag powder surface topography on viscoelastic characteristics and geometry of solar cell electrodes is studied. Numerical simulations for concentrated non‐Brownian suspensions show that shear viscosity and storage modulus increase with particle roughness. Experimental rheological analysis shows improvement in thixotropy and shear storage modulus for pseudoplastic electrode materials with corrugated Ag powders. Consequently, viscoelastic recovery is enhanced for frontside electrode gridlines with rough‐surface Ag powders. This results in aspect‐ratio and cross‐sectional symmetry enhancement for rough‐surface Ag powder gridlines compared with smooth‐surface Ag powder gridlines. Rough‐surface Ag powder gridlines have smaller height variations, making them more suitable for high‐throughput screen printing. Optical simulations show improved light redirection into the solar cell for gridlines formed from rough‐surface Ag powders, leading to higher solar cell photocurrent. The improved gridline definition results in an increase in short‐circuit current density, yielding average efficiency improvement of ≈0.1% absolute for monocrystalline‐Si solar cells with screen‐printed gridlines having rough‐surface Ag powders. This results in monocrystalline‐Si solar cells with 22.45% average conversion efficiency.
One‐time N fertilization reduces greenhouse emissions and N leaching while maintaining high yields in a rape–rice rotation system
Authors: Ding Wuhan , Lei Haojie , Zhang Jing , Wang Ligang , Zhang Jianfeng , Ju Xuehai , Li Hu , Zhang Guilong
Published: November 2021

In China, the rice (Oryza sativa L.)–rapeseed (Brassica napus L.) rotation system is facing great challenges, including constantly growing demand, on‐going labor shortages, and increasing environmental burdens. Thus, producing more food and higher benefits while minimizing environmental costs is required for future development. A 2‐yr field experiment comparing three nitrogen (N) fertilization treatments (non‐N treatment as control [CK], conventional urea application [CU], one‐time application of controlled‐release urea [CRU]) was performed. Results showed that the rice season dominated annual CH4 emissions (>95%) and on average contributed more than 50% of the annual N2O emissions. Additionally, the main forms of mineral N leaching were different for rape and rice. Nitrate (NO3–)–N was the major component of leaching in rape season, while for rice season NO3––N and NH4+–N were equal. Relative to CU, CRU significantly increased the rapeseed yield by 10.7∼13.9% and maintained the rice productivity, reduced mineral N leaching losses by 19.6∼20.8% for the rice season, and resulted in less total methane (CH4) and nitrous oxide (N2O) emissions (TGHGs) by 12.1% across the two rotations. Furthermore, a net economic benefit (NEB) considering yields, fertilizer input, labor, and other input costs indicated CRU increased the economic return by 58.3%. However, CRU did not improve partial factor productivity of nitrogen fertilizer (PFPN) and decreased the NEB by 3.1% without considering the labor cost. It indicated a one‐time application of the CRU for rice–rapeseed rotation system was an environmentally and economically profitable technology. This paper provided a promising solution for farmers to enhance rice–rapeseed productivity and increase income while minimizing the environmental footprint.
The impact of DNA testing on management of patients with colorectal cancer
Authors: Howe James R.
Published: November 2021

Knowledge of the genetic basis of colorectal cancer has evolved over the past decades, allowing for the pre‐symptomatic identification of affected patients in those with familial syndromes and to the understanding of the multi‐step progression to carcinogenesis in tumors. Knowledge of the genes and pathways involved in colorectal cancer has allowed for targeted therapies in patients in addition to standard chemotherapy for those with metastases. Next‐generation sequencing technologies have now also allowed for the sensitive detection of circulating mutations derived from tumors, which can give insight into the presence of residual disease and has implications for changing the standard paradigms for treatment. This article will specifically review advances in targeted therapy in metastatic colon cancer and the progress being made in using circulating tumor DNA in patient management.
Wood density relates negatively to maximum plant height across major angiosperm and gymnosperm orders
Authors: Fajardo Alex
Published: November 2021

Premise

Wood density is a crucial plant functional trait related to plant life history strategies. Its ecological importance in small‐stature growth forms (e.g., shrubs) has not been extensively examined. Given that hydraulic conduit dimensions vary positively with plant height and that there is a negative relationship between conduits' diameter and wood density, I hypothesized an also negative relationship between wood density and plant height. Knowing that bark and pith proportions are significant in small‐diameter stems, I additionally disentangled the contribution of wood, bark, and pith to stem density.

Methods

I determined density in small‐diameter stems across 153 species spanning all major angiosperm and gymnosperm orders by considering a diversity of growth forms (trees, treelets, shrubs, vines, and hemiparasites). Stem cross sections were dissected to consider the densities of wood with bark and pith; wood with pith and without bark; wood with bark and no pith; and wood without bark and pith. Secondary growth was also measured.

Results

Trees showed similar wood densities as non‐self‐supporting vines, and both showed significantly less dense wood than treelets, shrubs, and hemiparasites. General comparisons showed that wood was significantly denser than all other tissues, and these differences did not depend on growth form. Wood density was significantly and negatively related to growth rate and pith area proportions but not to bark thickness proportion.

Conclusions

An implicit negative relationship between maximum plant height and stem density emerges as a property of plants likely linked to hydraulic conductive size.
Brønstedsäure‐Zentren in Zeolith SSZ‐42 werden von Wasserstoffbrücken dominiert – eine Einteilung ihrer Vielfalt
Authors: Schroeder Christian , Zones Stacey I. , Hansen Michael Ryan , Koller Hubert
Published: November 2021

Der Zeolithkatalysator SSZ‐42 besitzt einen außerordentlich hohen Anteil von Wasserstoff‐verbrückten Brønstedsäure‐Zentren (Brønsted acid sites, BAS) von ≈80 %, deren 1H chemische Verschiebung verglichen mit unverbrückten BAS (bei typischerweise 4 ppm) stärker entschirmt ist. Dies kommt durch die Wechselwirkung aufgrund einer günstigen Ausrichtung zu benachbarten Sauerstoffatomen des Zeolithgerüsts zustande. Eine Einteilung der Vielfalt der Wasserstoffbrücken wurde durch DFT‐Rechnungen beleuchtet, wobei 5‐Ringe und ovale 6‐Ringe zu stärkeren Wasserstoffbrücken zwischen entgegengesetzten Seiten der Ringe führen (höhere experimentelle Verschiebung, δ(1H)=6.4 ppm) als kreisförmige 6‐Ringe (δ(1H)=5.2 ppm). Käfigartige Strukturen und intra‐tetraedrische Wechselwirkungen können ebenfalls zu Wasserstoffbrücken führen. Es ist zu erwarten, dass die Ausrichtung von Sauerstoffatomen deren Rolle bei der Stabilisierung von katalytischen Zwischenprodukten beeinflussen, wie Oberflächen‐Alkoxy‐Gruppen und möglicherweise auch Übergangszustände.
Imaging Membrane Order and Dynamic Interactions in Living Cells with a DNA Zipper Probe
Authors: Bagheri Yousef , Ali Ahsan Ausaf , Keshri Puspam , Chambers James , Gershenson Anne , You Mingxu
Published: November 2021

The cell membrane is a dynamic and heterogeneous structure composed of distinct sub‐compartments. Within these compartments, preferential interactions occur among various lipids and proteins. Currently, it is still challenging to image these short‐lived membrane complexes, especially in living cells. In this work, we present a DNA‐based probe, termed “DNA Zipper”, which allows the membrane order and pattern of transient interactions to be imaged in living cells using standard fluorescence microscopes. By fine‐tuning the length and binding affinity of DNA duplex, these probes can precisely extend the duration of membrane lipid interactions via dynamic DNA hybridization. The correlation between membrane order and the activation of T‐cell receptor signaling has also been studied. These programmable DNA probes function after a brief cell incubation, which can be easily adapted to study lipid interactions and membrane order during different membrane signaling events.
Polyacids for producing colloidally stable amorphous calcium carbonate clusters in water
Authors: Jia Xianjing , Kayitmazer A. Basak , Ahmad Ayyaz , Ramzan Naveed , Li Yongsheng , Xu Yisheng , Sun Shengtong
Published: November 2021

As an important precursor of crystalline phases, amorphous calcium carbonate (ACC), especially ultrasmall ACC clusters, have been attracting great interest in fundamental research, materials chemistry, as well as industrial applications. However, it is still challenging to synthesize stable ACC clusters in water that can be isolated and concentrated without severe aggregation. Herein, we report a facile dialysis method for producing colloidally stable ACC clusters that are well dispersed in water with the protection of specific polycarboxylic acids, which could be also easily deprotected by small‐molecule acids like sodium citrate. Inherent proto‐calcite short‐range order is found to be present in all the obtained ACC clusters. The present strategy not only allows for the preparation of monodisperse isolated ACC clusters in aqueous solution but also shows great potential in industrial uses like waste water treatment.
Alcohol‐associated capillarization of sinusoids: A critique since the discovery by Schaffner and Popper in 1963
Authors: Mak Ki M. , Kee Dustin , Shin Da Wi
Published: November 2021

This article reviews the literature on capillarization of hepatic sinusoids since its discovery in 1963. Liver sinusoidal endothelial cells are uniquely fenestrated and lack an underlying basement membrane. In chronic liver disease, the sinusoids capillarize and transform into systemic capillaries, a process termed capillarization of sinusoids. The histopathology is marked by defenestration, basement membrane formation, and space of Disse fibrogenesis. Capillarized sinusoids compromise the bidirectional exchange of materials between sinusoids and hepatocytes, leading to hepatocellular dysfunction. Sinusoidal capillarization was first described in active cirrhosis of alcoholics in 1963. Since then, it has been found in early and progressive stages of alcoholic hepatic fibrosis before the onset of cirrhosis. The sinusoidal structure is not altered in alcoholic steatosis without fibrosis. Defenestration impairs the ability of the endothelium to filter chylomicron remnants from sinusoids into the Disse's space, contributing to alcohol‐induced postprandial hyperlipidemia and possibly atherosclerosis. Ethanol also modulates the fenestration dynamics in animals. In baboons, chronic alcohol consumption diminishes endothelial porosity in concomitance with hepatic fibrogenesis and in rats defenestrates the endothelium in the absence of fibrosis, and sometimes capillarizes the sinusoids. Acute ethanol ingestion enlarges fenestrations in rats and contracts fenestrations in rabbits. In sinusoidal endothelial cell culture, ethanol elicits fenestration dilation, which is likely related to its interaction with fenestration‐associated cytoskeleton. Ethanol potentiates sinusoidal injury caused by cocaine, acetaminophen or lipopolysaccharide in mice and rats. Understanding ethanol's mechanisms on pathogenesis of sinusoidal capillarization and fenestration dynamics will lead to development of methods to prevent risks for atherosclerosis in alcoholism.
Insights into the chemistry and therapeutic potential of acrylonitrile derivatives
Authors: Unsal Tan Oya , Zengin Merve
Published: November 2021

Acrylonitrile is a fascinating scaffold widely found in many natural products, drugs, and drug candidates with various biological activities. Several drug molecules such as entacapone, rilpivirine, teriflunomide, and so forth, bearing an acrylonitrile moiety have been marketed. In this review, diverse synthetic strategies for constructing desired acrylonitriles are discussed, and the different biological activities and medicinal significance of various acrylonitrile derivatives are critically evaluated. The information gathered is expected to provide rational guidance for the development of clinically useful agents from acrylonitriles.
A Modular System for the Rapid Comparison of Different Membrane Anchors for Surface Display on Escherichia coli
Authors: Gallus Sabrina , Mittmann Esther , Rabe Kersten S.
Published: November 2021

Comparison of different membrane anchor motifs for the surface display of a protein of interest (passenger) is crucial for achieving the best possible performance. However, generating genetic fusions of the passenger to various membrane anchors is time‐consuming. We herein employ a recently developed modular display system, in which the membrane anchor and the passenger are expressed separately and assembled in situ via SpyCatcher and SpyTag interaction, to readily combine a model passenger cytochrome P450 BM3 (BM3) with four different membrane anchors (Lpp‐OmpA, PgsA, INP and AIDA‐I). This approach has the significant advantage that passengers and membrane anchors can be freely combined in a modular fashion without the need to generate direct genetic fusion constructs in each case. We demonstrate that the membrane anchors impact not only cell growth and membrane integrity, but also the BM3 surface display capacity and whole‐cell biocatalytic activity. The previously used Lpp‐OmpA as well as PgsA were found to be efficient for the display of BM3 via SpyCatcher/SpyTag interaction. Our strategy can be transferred to other user‐defined anchor and passenger combinations and could thus be used for acceleration and improvement of various applications involving cell surface display.
Use of iso‐osmolar contrast media during endovascular revascularization is associated with a lower incidence of major adverse renal, cardiac, or limb events
Authors: Prasad Anand , Amin Amit P. , Ryan Michael P. , Gunnarsson Candace , Brilakis Emmanouil S.
Published: November 2021

Objective

We examined the association of iso‐osmolar contrast media (IOCM) versus low‐osmolar contrast media (LOCM) with major adverse renal, cardiovascular, or limb events in patients at high‐risk of acute kidney injury (AKI) undergoing peripheral endovascular procedures.

Background

Procedural characteristics including iodinated contrast type and volume have been associated with adverse renal and cardiovascular outcomes in patients undergoing angiographic interventions.

Methods

Patients at high‐risk of AKI, undergoing peripheral endovascular procedures were identified using the Premier Healthcare Database and separated into claudication and critical limb ischemia (CLI) cohorts. For each cohort, we compared IOCM versus LOCM for the primary endpoint of MARCE (major adverse renal or cardiovascular events) and secondary endpoints of major adverse renal events (MARE) and major adverse renal and limb events (MARLE). These outcomes were captured within the indexed hospitalization via adjusted multivariable regression analyses.

Results

Two procedure‐based cohorts of high‐risk patients were formed: claudication (N = 11,976) and CLI (N = 8713). Use of IOCM was associated with a significant absolute risk reduction (ARR) of 2.2% (p < 0.0001) for MARCE overall and in each cohort (claudication, 1.8%, p = 0.0070; CLI, 2.7%, p = 0.0054). The incidence of MARE and MARLE in the overall cohort was also lower with the use of IOCM: MARE (ARR = 1.4%, p = 0.0072) and MARLE (ARR = 2.0%, p = 0.0043).

Conclusions

Using IOCM versus LOCM in patients at high‐risk of adverse renal events undergoing peripheral endovascular procedures was independently associated with lower risk of MARCE, MARE, and MARLE.
Bromine Substitution of Organic Modifiers Fixed on a Titanium(IV) Oxide Photocatalyst: A New Strategy Accelerating Visible Light‐Induced Hydrogen‐Free Hydrogenation of Furfural to Furfuryl Alcohol
Authors: Yamamoto Yuhei , Toda Hibiki , Tanaka Atsuhiro , Kominami Hiroshi
Published: November 2021

Titanium(IV) oxide (TiO2) modified with 2,3‐naphthalenediol (NDO) works as a photocatalyst for some reactions under irradiation of visible light. We prepared and characterized nine kinds of organically modified TiO2 (OM/TiO2) and used OM/TiO2 for chemoselective hydrogenation of furfural (FAL) to furfuryl alcohol (FOL) under irradiation of visible light without the use of hydrogen gas. All OM/TiO2 prepared in this study produced FOL and a linear relation between the reaction rate and amount of FAL adsorbed on the OM/TiO2 was observed. Among them, OM/TiO2 having bromine (Br)‐substituted NDO exhibited larger reaction rates and the rate increased with an increase in the number of Br groups. In the case of the most active 1,4,6‐tribromo‐2,3‐naphthalenediol‐modified TiO2 (TB‐NDO/TiO2), the reaction rate was not dependent on the amount of TB‐NDO and the photoabsorption of TB‐NDO/TiO2 but was dependent on the amount of FAL adsorbed on TB‐NDO/TiO2. These results revealed that substitution of hydrogen atoms of organic modifiers with Br is a simple but effective method for increasing the photocatalytic activity. The explored TB‐NDO/TiO2 also showed high performance in H2‐free chemoselective reduction of benzaldehydes having reducible groups to corresponding benzyl alcohols.
1D GNR‐PPy Composite for Remarkably Sensitive Detection of Heavy Metal Ions in Environmental Water**
Authors: Kulkarni Bhakti B. , Suvina V. , Balakrishna R. Geetha , Nagaraju D. H. , Jagadish Kusuma
Published: November 2021

The work reported here exploits the extraordinary features of graphene nanoribbons (GNR) and well‐known conductive polypyrrole (PPy) polymer to develop a very good electrochemically active composite for sensing metal ions. A strong hydrogen bond and π‐π interaction between the two components facilitates an enhanced conductive 3D network that has been used to design and fabricate an electrochemical sensor for selective and sensitive determination of Pb2+ ions by differential pulse voltammetry (DPV). The probe has been further extended to simultaneously detect Zn2+, Cd2+, As2+, Cu2+, Pb2+, Fe2+ and Hg2+ ions. Moreover, the larger effective surface area, higher porosity and chelating groups of composite promotes better adsorption‐stripping process of Pb2+ ions, leading to a high detection limit of 0.03 nM with a sensitivity of 0.7557 μA μM−1cm−2. This study is extended to detect heavy metal ions in lake water samples, demonstrating promising applications in real time (environmental) samples, and the study shows a deviation of ≈10 %, when validated with atomic absorption spectroscopy studies.
Emerging adulthood milestones, perceived capability, and psychological well‐being while transitioning to adulthood: Evidence from a national study
Authors: Chatterjee Swarn , Kim Jinhee , Chung Saerom
Published: November 2021

Using the 2017 wave of the transition to adulthood dataset, this study examined the association between the achievement of key milestone markers of adulthood and the well‐being of emerging adults between ages 18 and 28. Results indicate that relationship status, financial behavior, and perceived capability were positively associated with the well‐being of emerging adults. The results also indicate that financial responsibility, mediated by cohabiting relationship status, was negatively associated with relationship satisfaction and life satisfaction of emerging adults. All relationship categories were positively associated with well‐being when compared with the reference group of emerging adults who were single and not in a relationship. The study also found that being African Americans or other racial‐ethnic minority groups was negatively associated with life satisfaction, thus indicating a greater need for programs and policies to bridge the gap in perceived well‐being that currently exists between Non‐Hispanic Whites and other racial‐ethnic minority groups. Educational attainment was positively associated with the perceived well‐being of emerging adults. Implications of the key findings of this study are included for financial planners, scholars, and policymakers.
Intramolecular N−H⋅⋅⋅F Hydrogen Bonding Interaction in a Series of 4‐Anilino‐5‐Fluoroquinazolines: Experimental and Theoretical Characterization of Electronic and Conformational Effects
Authors: Urner Lorenz M. , Young Lee Ga , Treacy Joseph W. , Turlik Aneta , Khan Saeed I. , Houk K. N. , Jung Michael E.
Published: November 2021

The 4‐anilino‐6,7‐ethylenedioxy‐5‐fluoroquinazoline scaffold is presented as a novel model system for the characterization of the weak NH⋅⋅⋅F hydrogen bonding (HB) interaction. In this scaffold, the aniline NH proton is forced into close proximity with the nearby fluorine (dH,F∼2.0 Å, ∠∼138°), and a through‐space interaction is observed by NMR spectroscopy with couplings (1hJNH,F) of 19±1 Hz. A combination of experimental (NMR spectroscopy and X‐ray crystallography) and theoretical methods (DFT calculations) were used for the characterization of this weak interaction. In particular, the effects of conformational rigidity and steric compression on coupling were investigated. This scaffold was used for the direct comparison of fluoride with methoxy as HB acceptors, and the susceptibility of the NH⋅⋅⋅F interaction to changes in electron distribution and resonance was probed by preparing a series of molecules with different electron‐donating or ‐withdrawing groups in the positions para to the NH and F. The results support the idea that fluorine can act as a weak HB acceptor, and the HB strength can be modulated through additive and linear electronic substituent effects.
Chemistry on the Complex: Derivatization of TiO4N2‐Based Complexes and Application to Multi‐Step Synthesis
Authors: Scarpi‐Luttenauer Matthieu , Kyritsakas Nathalie , Chaumont Alain , Mobian Pierre
Published: November 2021

The chemistry on octahedral TiO4N2‐complexes is described. The Ti(IV)‐based precursors are composed of two 3,3’‐diphenyl‐2,2’‐biphenolato ligands (1) and one substituted 1,10‐phenanthroline ligand (2‐5). The application of imine condensation, palladium‐catalyzed C−C bond formation or copper‐catalysed azide‐alkyne cycloaddition allowed the grafting of various new groups onto these species. In particular Sonogashira reactions permitted to observe an excellent conversion of the starting complexes. This systematic study enabled to compile the factors required to preserve the framework of the complexes in the course of a chemical transformation. Thanks to this chemistry realized on the complex, the Ti(1)2 fragment was used as a protecting group to develop a multi‐step synthesis of a bis‐phenanthroline compound (12), for which the synthesis without this protection failed. Thus, a dinuclear complex [Ti2(1)4(12)] was first prepared starting from complex precursor bearing an acetylenic function via a Hay coupling reaction. This was followed by a deprotection step affording 12. Overall, this work illustrates how the Ti(1)2 fragment could be an useful tool for the preparation of unprecedented diimine compounds.
Merging of a Perylene Moiety Enables a RuII Photosensitizer with Long‐Lived Excited States and the Efficient Production of Singlet Oxygen
Authors: Schmid Marie‐Ann , Brückmann Jannik , Bösking Julian , Nauroozi Djawed , Karnahl Michael , Rau Sven , Tschierlei Stefanie
Published: November 2021

Multichromophoric systems based on a RuII polypyridine moiety containing an additional organic chromophore are of increasing interest with respect to different light‐driven applications. Here, we present the synthesis and detailed characterization of a novel RuII photosensitizer, namely [(tbbpy)2Ru((2‐(perylen‐3‐yl)‐1H‐imidazo[4,5‐f][1,10]‐phenanthrolline))](PF6)2 RuipPer, that includes a merged perylene dye in the back of the ip ligand. This complex features two emissive excited states as well as a long‐lived (8 μs) dark state in acetonitrile solution. Compared to prototype [(bpy)3Ru]2+‐like complexes, a strongly altered absorption (ϵ=50.3×103 M−1 cm−1 at 467 nm) and emission behavior caused by the introduction of the perylene unit is found. A combination of spectro‐electrochemistry and time‐resolved spectroscopy was used to elucidate the nature of the excited states. Finally, this photosensitizer was successfully used for the efficient formation of reactive singlet oxygen.
Elucidating the Supramolecular Copolymerization of N‐ and C‐Centered Benzene‐1,3,5‐Tricarboxamides: The Role of Parallel and Antiparallel Packing of Amide Groups in the Copolymer Microstructure
Authors: de Windt Lafayette N. J. , Fernández Zulema , Fernández‐Míguez Manuel , Freire Félix , Palmans Anja R. A.
Published: November 2021

An in‐depth study of the supramolecular copolymerization behavior of N‐ and C‐centered benzene‐1,3,5‐tricarboxamides (N‐ and C‐BTAs) has been conducted in methylcyclohexane and in the solid state. The connectivity of the amide groups in the BTAs differs, and mixing N‐ and C‐BTAs results in supramolecular copolymers with a blocky microstructure in solution. The blocky microstructure results from the formation of weaker and less organized, antiparallel hydrogen bonds between N‐ and C‐BTAs. In methylcyclohexane, the helical threefold hydrogen‐bonding network present in C‐ and N‐BTAs is retained in the mixtures. In the solid state, in contrast, the hydrogen bonds of pure BTAs as well as their mixtures organize in a sheet‐like pattern, and in the mixtures long‐range order is lost. Drop‐casting to kinetically trap the solution microstructures shows that C‐BTAs retain the helical hydrogen bonds, but N‐BTAs immediately adopt the sheet‐like pattern, a direct consequence of the lower stabilization energy of the helical hydrogen bonds. In the copolymers, the stability of the helical aggregates depends on the copolymer composition, and helical aggregates are only preserved when a high amount of C‐BTAs is present. The method outlined here is generally applicable to elucidate the copolymerization behavior of supramolecular monomers both in solution as well as in the solid state.
Chirality determination in crystals
Authors: Valentín‐Pérez Ángela , Rosa Patrick , Hillard Elizabeth A. , Giorgi Michel
Published: November 2021

This tutorial review article discusses chirality determination in the solid state, both in single crystals and in crystal assemblies, with an emphasis on X‐ray diffraction. The main principles of using X‐ray diffraction to reliably determine absolute structure are summarized, and the complexity which can be encountered in chiral structures—kryptoracemates, scalemates, and inversion twinning—is illustrated with examples from our laboratories and the literature. We then address the problem of the bulk crystallization and discuss different techniques to determine chirality in a large assembly of crystal structures, with a special prominence given to an X‐ray natural circular dichroism mapping technique that we recently reported.
Synthesis of Graphene Oxide Membrane for Separation of p‐Xylene and o‐Xylene by Pervaporation
Authors: Guo Hao , Wan Zheng , Li Yanhong , He Xiao , Huang Aisheng
Published: November 2021

In this study, a graphene oxide (GO) membrane is developed for the separation of p‐xylene (PX, 0.58 nm) from o‐xylene (OX, 0.68 nm). Attributing to the suitable d‐spacing size (0.58 nm), the GO membrane allows more PX to pass through than OX, leading to a high PX/OX selectivity. At 110 °C for the separation of equimolar PX/OX mixture, the PX/OX separation factor is 9.4 and PX flux is 145.3 g m−2h−1, respectively, which is promising for the separation of xylene isomers by pervaporation. The separation performance of the GO membrane is further confirmed by simulation studies.