bluuebunny/crossref_metadata_2025 huggingface dataset:
Post‐Modification of a Robust Covalent Organic Framework for Efficient Sequestration of 99TcO4−/ReO4−
Authors: Zhu Lei , Li Hai‐Ruo , Liu Zhao‐Fei , Di Zhengyi , Xu Wengui , Zhang Libo , Li Cheng‐Peng
Published: August 2023

Nuclear industry spent fuel reprocessing and some radioactive contamination sites often involve high acidity and salinity environments. Currently developed and reported sorbents in 99TcO4− sequestration from the nuclear waste are unstable and show low adsorption efficiency in harsh conditions. To address this issue, we developed a post‐synthetic modification strategy by grafting imidazole‐based ionic liquids (ILs) onto the backbone of covalent organic framework (COF) via vinyl polymerization. The resultant COF‐polyILs sorbent exhibits fast adsorption kinetics (<5 min) and good sorption capacity (388 mg g−1) for ReO4− (a nonradioactive surrogate of 99TcO4−). Outstandingly, COF‐polyILs composite shows superior ReO4− removal even under highly acidic conditions and in the presence of excess competing ions of Hanford low‐level radioactive waste stream, benefiting from the stable covalent bonds between the COF and polyILs, mass of imidazole rings, and hydrophobic pores in COF.
Continuous‐Flow Synthesis of Cycloparaphenylene Building Blocks on a Large Scale
Authors: Griwatz Jan H. , Kessler Mika L. , Wegner Hermann A.
Published: August 2023

The synthesis of [n]cycloparaphenylenes ([n]CPPs) and similar nanohoops is usually based on combining building blocks to a macrocyclic precursor, which is then aromatized in the final step. Access to those building blocks in large amounts will simplify the synthesis and studies of CPPs as novel functional materials for applications. Herein, we report a continuous‐flow synthesis of key CPP building blocks by using versatile synthesis techniques such as electrochemical oxidation, lithiations and Suzuki cross‐couplings in self‐built reactors on up‐to kilogram scale.
Advances in RNA Labeling with Trifluoromethyl Groups
Authors: Eichler Clemens , Himmelstoß Maximilian , Plangger Raphael , Weber Leonie I. , Hartl Markus , Kreutz Christoph , Micura Ronald
Published: August 2023

Fluorine labeling of ribonucleic acids (RNA) in conjunction with 19F NMR spectroscopy has emerged as a powerful strategy for spectroscopic analysis of RNA structure and dynamics, and RNA‐ligand interactions. This study presents the first syntheses of 2′‐OCF3 guanosine and uridine phosphoramidites, their incorporation into oligoribonucleotides by solid‐phase synthesis and a comprehensive study of their properties. NMR spectroscopic analysis showed that the 2′‐OCF3 modification is associated with preferential C2′‐endo conformation of the U and G ribose in single‐stranded RNA. When paired to the complementary strand, slight destabilization of the duplex caused by the modification was revealed by UV melting curve analysis. Moreover, the power of the 2′‐OCF3 label for NMR spectroscopy is demonstrated by dissecting RNA pseudoknot folding and its binding to a small molecule. Furthermore, the 2′‐OCF3 modification has potential for applications in therapeutic oligonucleotides. To this end, three 2′‐OCF3 modified siRNAs were tested in silencing of the BASP1 gene which indicated enhanced performance for one of them. Importantly, together with earlier work, the present study completes the set of 2′‐OCF3 nucleoside phosphoramidites to all four standard nucleobases (A, U, C, G) and hence enables applications that utilize the favorable properties of the 2′‐OCF3 group without any restrictions in placing the modification into the RNA target sequence.
Idiopathic premature ventricular complexes treatment: Comparison of flecainide, propafenone, and sotalol
Authors: Kojić Dejan , Radunović Anja , Bukumirić Zoran , Rajsic Sasa , Sušić Maša , Marić Marija , Žugić Vasko , Jurčević Ružica , Tomović Milosav
Published: August 2023

Background

Beta‐blockers (BB) or dihydropyridine calcium channel blockers (CCBs) are still the first choices in the treatment of idiopathic premature ventricular complexes (PVCs), with low‐modest efficacy. Antiarrhythmic drugs (AADs) of Ic class are moderate to highly efficient but the evidence on their benefits is still limited.

Aim

To compare effectiveness and safety of flecainide, propafenone, and sotalol in the treatment of symptomatic idiopathic PVCs.

Methods

Our single‐center retrospective study analyzed 104 consecutive patients with 130 medication episodes of frequent idiopathic PVCs treated with AADs flecainide, propafenone (Ic class) or sotalol (III class). The primary outcome was complete/near complete reduction of PVCs after medication episode (PVCs burden reduction >99%), and the secondary outcome was significant PVC burden reduction (≥80%).

Results

The complete/near complete PVCs burden reduction occurred in 31% and was significant in 43% of treated patients. A reduction of PVC burden for >99% was achieved in 56% of patients on flecainide, in 11% of patients on propafenone (p = .002), and in 21% of patients receiving sotalol (p = .031). There was no difference between propafenone and sotalol (p = .174). A reduction of PVC burden for ≥80% was achieved in 64% of patients on flecainide, in 30% of patients on propafenone (p = .009), and 33% of patients on sotalol (p = .020). There was no difference between propafenone and sotalol (p = .661).

Conclusions

The efficacy of AADs class Ic and III in the treatment of idiopathic PVCs was modest. Flecainide was the most effective AAD in the achievement of complete/near complete or significant PVC burden reduction, compared to propafenone and sotalol.
Eco‐friendly Synthesis of Silver Nanoparticles and its Application in Hydrogen Photogeneration and Nanoplasmonic Biosensing
Authors: Strapasson Guilherme B. , de C. Flach Eduarda , Assis Marcelo , Corrêa Silma A. , Longo Elson , Machado Giovanna , Santos Jacqueline F. L. , Weibel Daniel E.
Published: August 2023

Environmentally friendly methods for silver nanoparticles (AgNPs) synthesis without the use of hazardous chemicals have recently drawn attention. In this work, AgNPs have been synthesized by microwave irradiation using only honey solutions or aqueous fresh pink radish extracts. The concentrations of honey, radish extract, AgNO3 and pH were varied. AgNPs presented mean sizes between 7.0 and 12.8 nm and were stable up to 120 days. The AgNPs were employed as co‐catalyst (TiO2@AgNPs) to increase the hydrogen photogeneration under UV‐vis and only visible light irradiation, when compared to pristine TiO2 NPs. The prepared photocatalyst also showed hydrogen generation under visible light. Additionally, AgNPs were used to assemble a nanoplasmonic biosensor for the biodetection of extremely low concentrations of streptavidin, owing to its specific binding to biotin. It is shown here that green AgNPs are versatile nanomaterials, thus being potential candidates for hydrogen photogeneration and biosensing applications.
Development and validation of a short version of the questionnaire of stressful life events (QSLE)
Authors: Butjosa Anna , Usall Judith , Vila‐Badia Regina , Del Cacho Nuria , Gómez‐Benito Juana , Barajas Ana , Banos Iris , Grau Norma , Granell Luis , Sola Andrea , Hami‐Carlson Janina , Dolz Montserrat , Sanchez Bernardo ,   GENIPE group, Ochoa Susana
Published: August 2023

Stressful life events (SLE) tend to occur before the onset of psychosis, this highlights the importance of its detection and evaluation in these patients. The need to have instruments that assess SLE easily and quickly underpins the objective of this study, which is to validate a short version of the questionnaire of stressful life events (QSLE). 124 patients with first‐episode psychosis and 218 healthy controls aged between 11 and 52 years were recruited. The QSLE scale underwent discrimination analysis, which revealed 18 items had good SLEs discriminability between the two samples. These 18 items were then used to create the shorter QSLE‐SV. The QSLE‐SV showed good internal consistency (Cronbach's alpha = 0.749). An AUC of 0.830 was observed, suggesting that the predictor was good. Using 2 as the cut‐off score to predict an individual as a patient would yield a sensitivity of 91.1% and a specificity of 51.6%, and using a cut‐off point of 3, the sensitivity was 77.4% and the specificity was 72.5%. QSLE‐SV displayed satisfactory psychometric properties in a Spanish population. The QSLE‐SV allows for investigating childhood, adolescent and adult life events by measuring current stress and age on a continuous scale in a quick and easy way.
Fitness, behavioral, and energetic trade‐offs of different migratory strategies in a partially migratory species
Authors: Soriano‐Redondo Andrea , Franco Aldina M. A. , Acácio Marta , Payo‐Payo Ana , Martins Bruno Herlander , Moreira Francisco , Catry Inês
Published: August 2023

Alternative migratory strategies can coexist within animal populations and species. Anthropogenic impacts can shift the fitness balance between these strategies leading to changes in migratory behaviors. Yet some of the mechanisms that drive such changes remain poorly understood. Here we investigate the phenotypic differences, and the energetic, behavioral, and fitness trade‐offs associated with four different movement strategies (long‐distance and short‐distance migration, and regional and local residency) in a population of white storks (Ciconia ciconia) that has shifted its migratory behavior over the last decades, from fully long‐distance migration toward year‐round residency. To do this, we tracked 75 adult storks fitted with GPS/GSM loggers with tri‐axial acceleration sensors over 5 years, and estimated individual displacement, behavior, and overall dynamic body acceleration, a proxy for activity‐related energy expenditure. Additionally, we monitored nesting colonies to assess individual survival and breeding success. We found that long‐distance migrants traveled thousands of kilometers more throughout the year, spent more energy, and >10% less time resting compared with short‐distance migrants and residents. Long‐distance migrants also spent on average more energy per unit of time while foraging, and less energy per unit of time while soaring. Migratory individuals also occupied their nests later than resident ones, later occupation led to later laying dates and a lower number of fledglings. However, we did not find significant differences in survival probability. Finally, we found phenotypic differences in the migratory probability, as smaller sized individuals were more likely to migrate, and they might be incurring higher energetic and fitness costs than larger ones. Our results shed light on the shifting migratory strategies in a partially migratory population and highlight the nuances of anthropogenic impacts on species behavior, fitness, and evolutionary dynamics.
Irreversible phase back conversion of α‐FAPbI3 driven by lithium‐ion migration in perovskite solar cells
Authors: Choi Seung‐Gu , Lee Jin‐Wook
Published: August 2023

Typically n‐i‐p structured perovskite solar cells (PSCs) incorporate 2,2′,7,7′‐tetrakis (N,N‐di‐p‐methoxyphenyl amine)‐9,9′‐spirobifluorene (spiro‐OMeTAD) as the hole‐transporting material. Chemical doping of spiro‐OMeTAD involves a lithium bis(trifluoromethyl sulfonyl)imide dopant, causing complex side‐reactions that affect the device performance, which are not fully understood. Here, we investigate the aging‐dependent device performance of widely used formamidinium lead triiodide (FAPbI3)‐based PSCs correlated with lithium‐ion (Li+) migration. Comprehensive analyses reveal that Li+ ions migrate from spiro‐OMeTAD to perovskite, SnO2, and their interfaces to induce the phase‐back conversion of α‐FAPbI3 to δ‐FAPbI3, generation and migration of iodine defects, and de‐doping of spiro‐OMeTAD. The rapid performance drop of FAPbI3‐based PSCs, even aging under dark conditions, is attributed to a series of these processes. This study identifies the hidden side effects of Li+ ion migration in FAPbI3‐based PSCs that can guide further work to maximize the operational stability of PSCs.

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Aesthetic and efficient perovskite/Si tandem solar cells using luminescent down‐shifting textured anti‐reflection films
Authors: Jung Eui Dae , Kim Chan Ul , Noh Young Wook , Seo Seong Kuk , Noh Young Im , Choi Kyoung Jin , Song Myoung Hoon
Published: August 2023

Perovskite‐based tandem cells are emerging as new photovoltaic (PV) cells with a high efficiency that exceeds the efficiency limit of single‐junction cells. Building‐integrated PVs that require high efficiency are attractive, but aesthetics play key roles in these urban applications. One of the most challenging problems with respect to aesthetic PV cells is the efficiency loss due to color tuning. Here, we demonstrate for the first time lossless full‐color tunable PV cells based on the use of textured luminescent down‐shifting (LDS) films with LDS dyes with ultraviolet‐selective absorption. The LDS anti‐reflection (AR) films improve the perovskite/Si tandem cell efficiency by reducing the loss of parasitic UV absorption of the layers above the perovskite film due to LDS effect and the loss due to cell reflection due to the textured surface. Therefore, color tuning with LDS AR films can be used to produce highly aesthetic and efficient PV cells for urban applications.

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Effects of superfine grinding sweet potato leaf powders on physicochemical and structure properties of sweet potato starch noodles
Authors: Li Guanghui , Gao Xueli , Wang Yonghui , He Shenghua , Guo Weiyun , Huang Jihong
Published: August 2023

Sweet potato leaves (SPLs) containing abundant functional components are consumed primarily as fresh vegetables worldwide. This study investigated the physical properties of superfine grinding SPLs powder, and their effects on cooking, texture, and sensory properties, micro‐ and molecular structures of starch noodles were also explored. The results showed that the bulk and tapped density (from 0.34 to 0.28 g/mL3 and from 0.69 to 0.61 g/mL3), repose and slid angle (from 42.15 to 30.96° and from 48.67 to 22.00°), water‐holding capacity and swelling capacity (from 8.66 to 4.94 g/g and from 10.03 to 7.77 mL/g) of SPLs powders were decreased with milling time increased. The cooking loss, swelling index, texture, and sensory properties of SPLs sweet potato starch noodles (SPLSNs) were improved as the particle size of SPLs decreased. XRD and FT‐IR showed that SPLSNs contained less complete crystallites (from 28.85% to 14.19%) and lower proportion of crystalline region (R1047/1017 from 0.96 to 0.81, R1017/994 from 0.41 to 0.43). SEM revealed that SPLSNs exhibited fewer ordered arrays and smooth cross sections. Our findings provide a foundation for utilizing SPLs and developing functional starch noodles.
Are foreign‐born CEOs held to a higher performance standard? The role of national origin in CEO dismissals
Authors: Thams Yannick , Rickley Marketa
Published: August 2023

Research Summary

Foreign‐born chief executive officers (CEOs) are increasingly common in US corporations. However, little is known about whether they are held to the same performance standard as native‐born CEOs. We examine whether CEO national origin moderates the relationship between firm performance and CEO dismissal. Drawing on social identity and attribution theories, we argue that CEO foreignness becomes more salient when firm performance is poor, increasing foreign‐born CEOs' dismissal likelihood. Using a large sample of US firms, we find that at low levels of performance, the dismissal probability for foreign‐born CEOs is 15.96% compared to 4.02% for native‐born CEOs. While the increase in foreign‐born CEOs in US corporations may reflect the declining importance of national origin for C‐suite appointments, boards' evaluations of these “elite migrants” may be biased.

Managerial Summary

Foreign‐born leaders are increasingly common in US C‐suites and currently manage several global firms, including Google, Microsoft, and Pepsi. But, once hired, are foreign‐ and native‐born CEOs evaluated uniformly by corporate boards? Given that CEOs are more likely to be dismissed when firm performance is low, we compare dismissal likelihoods for foreign‐ and native‐born CEOs when performance is subpar. Using a sample of 11,947 observations from firms in the Standard & Poor's 1500, we find significant disparities in the dismissal likelihoods between the two groups. At low levels of performance and ceteris paribus, the dismissal likelihood for a foreign‐born CEO is 15.96% compared to 4.02% for a native‐born CEO, highlighting biases relating to foreign origin in CEO evaluations.
Different cognitive mechanisms used for solving open and closed math problems
Authors: Cui Jiaxin , Wang Shumin , Lv Liting , Ran Xiaomeng , Cui Zhanling , Zhou Xinlin
Published: August 2023

Problem‐solving skills are very important in our daily life. Almost all problem‐solving studies have addressed the cognitive correlates of solving closed problems, but only limited studies have investigated the cognitive mechanisms of solving open problems. The current study aimed to systematically examine differences between the cognitive mechanisms used for solving open and closed problems. In total, the abilities of 142 high school students to solve open and closed problems were assessed, as were a series of general cognitive abilities as controlled variates. Analogical reasoning uniquely contributed to solving both open and closed math problems, after controlling for age, gender, and inductive reasoning. Reactive cognitive flexibility (measured using the Wisconsin card sorting test) and spatial working memory uniquely correlated only with solving open and closed math problems, respectively. These findings suggest that the cognitive processes used to solve open and closed math problems differ. Open and closed math problems appear to require more reactive cognitive flexibility for generation and more memory for retrieval, respectively.
Human resource attendance mechanism based on the internet of things: A method based on data fusion
Authors: Wu Qiong , Shen Ying
Published: August 2023

The development of Internet of Things technology makes people need to deal with an increasing amount of data, which brings the poor data quality, fast data generation speed and other problems. These problems have become one of the main obstacles restricting the development of human resource attendance. At present, data fusion methods as important methods in data fusion technology. This article fully utilizes human resource attendance data and proposes the LSTM‐Attention data fusion method. This method uses LSTM to model the data, extract potential features of the data, and filter out meaningful data in the human resource attendance mechanism through the Attention mechanism to achieve data fusion. Finally, experimental results in this article showed that the LSTM‐Attention data fusion method designed in this article has higher prediction accuracy. It fully mines the correlation between data, and further improves the accuracy of analysis and prediction in the human resource attendance mechanism based on the Internet of Things.
Modeling and optimization of biodiesel from high free‐fatty‐acid chicken fat by non‐catalytic esterification and mussel‐shell‐catalyzed transesterification
Authors: Rashid Israa M , Abdulwahab Yussur D , Mohammed Alaa Kareem , Wan Isahak Wan Nor Roslam , Jassam Bushra A
Published: August 2023

BACKGROUND

In this study, biodiesel was prepared from chicken fat via a transesterification reaction using Mussel shells as a catalyst. Pretreatment of chicken fat was carried out using non‐catalytic esterification to reduce the free fatty acid content from 36.28 to 0.96 mg KOH/g oil using an ethanol/ fat mole ratio equal to 115:1. In the transesterification reaction, the studied variables were methanol: oil mole ratio in the range of (6:1 ‐ 30:1), catalyst loading in the range of (9‐15) wt%, reaction temperature (55‐75 °C), and reaction time (1‐7) h. The heterogeneous alkaline catalyst was greenly synthesized from waste mussel shells throughout a calcination process at different calcination times of (1‐5) h and temperatures of (700‐900) °C. The catalyst was characterized using BET, SEM, EDX, XRD, and FTIR.

RESULTS

In the transesterification reaction, the best values of the studied parameters were: 21:1 methanol: oil molar ratio, 12 wt% catalyst loading, 5 h reaction time, and 63°C reaction temperature, which gave 96.2% methyl esters content. For catalyst synthesis, it was found that the optimum calcination conditions were 900 °C and 3 h, which resulted in a specific surface area of 10.5 m2/g and a large pore volume of 0.0033 cm3/g.

CONCLUSION

A calcium oxide catalyst was successfully prepared from mussel shells. This catalyst was used to transesterify the chicken fat into biodiesel. The prepared catalyst exhibited a high active surface area and a pore volume, confirming that the CaO catalyst produced from waste mussel shells worked effectively, steadily, and affordably to produce renewable biodiesel. The best working conditions for the transesterification reaction were determined using the central Composite Design method (CCD). © 2023 Society of Chemical Industry.
Should genes for non‐syndromic hearing loss be included in reproductive genetic carrier screening: Views of people with a personal or family experience of deafness
Authors: Freeman Lucinda , Bristowe Lisa , Kirk Edwin P. , Delatycki Martin B. , Scully Jackie Leach
Published: August 2023

Many commercial reproductive genetic carrier screening (RGCS) panels include genes associated with non‐syndromic hearing loss (NSHL), however little is known about the general acceptability of their inclusion. Although some couples wish to avoid having a deaf child, there are effective interventions and supports available for deafness, and no consensus on whether it is appropriate to reproductively screen NSHL genes. This study explored views of people with personal experience of deafness regarding carrier screening for genes associated with NSHL. We interviewed 27 participants; 14 who identified as deaf and 13 hearing parents of a deaf child. Thematic analysis was undertaken on transcripts of interviews. The findings reveal the complexity of attitudes within these groups. Some vacillated between the wish to support prospective parents' reproductive autonomy and concerns about potential harms, especially the expression of negative messages about deafness and the potential loss of acceptance in society. While some participants felt carrier screening could help prospective parents to prepare for a deaf child, there was little support for reproductive screening and termination of pregnancy. Participants emphasized the need for accurate information about the lived experience of deafness. The majority felt deafness is not as severe as other conditions included in RGCS, and most do not consider deafness as a disability. People with personal experience of deafness have diverse attitudes towards RGCS for deafness informed by their own identify and experience, and many have concerns about how it should be discussed and implemented in a population wide RGCS program.
Availability of screening and treatment for common mental disorders in HIV clinic settings: data from the global International epidemiology Databases to Evaluate AIDS (IeDEA) Consortium, 2016–2017 and 2020
Authors: Parcesepe Angela M. , Stockton Melissa , Remch Molly , Wester C. William , Bernard Charlotte , Ross Jeremy , Haas Andreas D. , Ajeh Rogers , Althoff Keri N. , Enane Leslie , Pape William , Minga Albert , Kwobah Edith , Tlali Mpho , Tanuma Junko , Nsonde Dominique , Freeman Aimee , Duda Stephany N. , Nash Denis , Lancaster Kathryn ,   the IeDEA Consortium
Published: August 2023

Introduction

Common mental disorders (CMDs) are highly prevalent among people with HIV. Integrating mental healthcare into HIV care may improve mental health and HIV treatment outcomes. We describe the reported availability of screening and treatment for depression, anxiety and post‐traumatic stress disorder (PTSD) at global HIV treatment centres participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) Consortium in 2020 and changes in availability at sites in low‐ or middle‐income countries (LMICs) between 2016/2017 and 2020.

Methods

In 2020, 238 sites contributing individual‐level data to the IeDEA Consortium and in 2016/2017 a stratified random sample of IeDEA sites in LMICs were eligible to participate in site surveys on the availability of screening and treatment for CMDs. We assessed trends over time for 68 sites across 27 LMICs that participated in both surveys.

Results

Among the 238 sites eligible to participate in the 2020 site survey, 227 (95%) participated, and mental health screening and treatment data were available for 223 (98%) sites across 41 countries. A total of 95 sites across 29 LMICs completed the 2016/2017 survey. In 2020, 68% of sites were in urban settings, and 77% were in LMICs. Overall, 50%, 14% and 12% of sites reported screening with a validated instrument for depression, anxiety and PTSD, respectively. Screening plus treatment in the form of counselling was available for depression, anxiety and PTSD at 46%, 13% and 11% of sites, respectively. Screening plus treatment in the form of medication was available for depression, anxiety and PTSD at 36%, 11% and 8% of sites, respectively. Among sites that participated in both surveys, screening for depression was more commonly available in 2020 than 2016/2017 (75% vs. 59%, respectively,p= 0.048).

Conclusions

Reported availability of screening for depression increased among this group of IeDEA sites in LMICs between 2016/2017 and 2020. However, substantial gaps persist in the availability of mental healthcare at HIV treatment sites across global settings, particularly in resource‐constrained settings. Implementation of sustainable strategies to integrate mental health services into HIV care is needed.
Salt effects on the reactivity for ligand substitution reactions of [Ru(CN)5OH2]3−anion with two naphthalene substituted ligands (nitroso‐R‐salt and α‐nitroso‐β‐naphthol) in presence of Tetrapropylammonium bromide (Pr4NBr) and Sodium chloride (NaCl)
Authors: Yadav Rupal , Srivastava Abhishek , Singh Ruchi , Naik Radhey Mohan , Yadav Shiv Bali Singh , Pandey Pradeep Kumar
Published: August 2023

The kinetics of the ligand exchange reaction between aquapentacyanoruthenate(II) [Ru(CN)5OH2]3−ion and naphthalene substituted ligands [α‐nitroso‐β‐naphthol (αNβN), and nitroso‐R‐salt (NRS)] has been studied in aqueous salt solutions of sodium chloride (NaCl) or tetrapropylammonium bromide (Pr4NBr) salt. The kinetics was monitored spectrophotometrically at 525 nm corresponding to the λmaxof reddish‐brown‐colored substituted products, [Ru(CN)5(αNβN)]3−or [Ru(CN)5(NRS)]3−. Increasing the ionic strength of the reaction mixture using NaCl, exerted a negative salt effect on the rate of formation of naphthalene‐substituted products. At the same time, an increment in the concentration of Pr4NBr imparted a positive salt effect on the reaction. The observed rate constant (kobs) exhibits linear increment with respect to the concentration of NRS or αNβN while remaining invariant with variation in [Ru(CN)5OH2]3−. The computed activation parameters for NRS (∆H# = 24.55 kJ mol−1,Ea = 27.03 kJ mol−1, ∆G# = 87.83 kJ mol−1, and ∆S# = – 212.5 J K−1 mol−1) and αNβN ((∆H# = 17.33 kJ mol−1,Ea = 19.81 kJ mol−1, ∆G# = 87.87 kJ mol−1, and ∆S# = – 236.7 J K−1 mol−1) also support the proposed mechanism.
Digital Light Processing 3D Bioprinting of Gelatin‐Norbornene Hydrogel for Enhanced Vascularization
Authors: Duong Van Thuy , Lin Chien‐Chi
Published: August 2023

Digital light processing (DLP) bioprinting can be used to fabricate volumetric scaffolds with intricate internal structures, such as perfusable vascular channels. The successful implementation of DLP bioprinting in tissue fabrication requires using suitable photo‐reactive bioinks. Norbornene‐based bioinks have emerged as an attractive alternative to (meth)acrylated macromers in 3D bioprinting owing to their mild and rapid reaction kinetics, high cytocompatibility for in situ cell encapsulation, and adaptability for post‐printing modification or conjugation of bioactive motifs. In this contribution, the development of gelatin‐norbornene (GelNB) is reported as a photo‐cross‐linkable bioink for DLP 3D bioprinting. Low concentrations of GelNB (2–5 wt.%) and poly(ethylene glycol)‐tetra‐thiol (PEG4SH) are DLP‐printed with a wide range of stiffness (G' ≈120 to 4000 Pa) and with perfusable channels. DLP‐printed GelNB hydrogels are highly cytocompatible, as demonstrated by the high viability of the encapsulated human umbilical vein endothelial cells (HUVECs). The encapsulated HUVECs formed an interconnected microvascular network with lumen structures. Notably, the GelNB bioink permitted both in situ tethering and secondary conjugation of QK peptide, a vascular endothelial growth factor (VEGF)‐mimetic peptide. Incorporation of QK peptide significantly improved endothelialization and vasculogenesis of the DLP‐printed GelNB hydrogels, reinforcing the applicability of this bioink system in diverse biofabrication applications.
Enhanced Maturation of 3D Bioprinted Skeletal Muscle Tissue Constructs Encapsulating Soluble Factor‐Releasing Microparticles
Authors: de Barros Natan Roberto , Darabi Mohammad Ali , Ma Xin , Diltemiz Sibel Emir , Ermis Menekse , Hassani Najafabadi Alireza , Nadine Sara , Banton Ethan A. , Mandal Kalpana , Abbasgholizadeh Reza , Falcone Natashya , Mano João F. , Nasiri Rohollah , Herculano Rondinelli Donizetti , Zhu Yangzhi , Ostrovidov Serge , Lee Junmin , Kim Han‐Jun , Hosseini Vahid , Dokmeci Mehmet R. , Ahadian Samad , Khademhosseini Ali
Published: August 2023

Several microfabrication technologies have been used to engineer native‐like skeletal muscle tissues. However, the successful development of muscle remains a significant challenge in the tissue engineering field. Muscle tissue engineering aims to combine muscle precursor cells aligned within a highly organized 3D structure and biological factors crucial to support cell differentiation and maturation into functional myotubes and myofibers. In this study, the use of 3D bioprinting is proposed for the fabrication of muscle tissues using gelatin methacryloyl (GelMA) incorporating sustained insulin‐like growth factor‐1 (IGF‐1)‐releasing microparticles and myoblast cells. This study hypothesizes that functional and mature myotubes will be obtained more efficiently using a bioink that can release IGF‐1 sustainably for in vitro muscle engineering. Synthesized microfluidic‐assisted polymeric microparticles demonstrate successful adsorption of IGF‐1 and sustained release of IGF‐1 at physiological pH for at least 21 days. Incorporating the IGF‐1‐releasing microparticles in the GelMA bioink assisted in promoting the alignment of myoblasts and differentiation into myotubes. Furthermore, the myotubes show spontaneous contraction in the muscle constructs bioprinted with IGF‐1‐releasing bioink. The proposed bioprinting strategy aims to improve the development of new therapies applied to the regeneration and maturation of muscle tissues.
Amphiphilic Zwitterionic Bioderived Block Copolymers from Glutamic Acid and Cholesterol – Ability to Form Nanoparticles and Serve as Vectors for the Delivery of 6‐Mercaptopurine
Authors: Leiske Meike N. , Kuenneth Christopher , De Breuck Jonas , De Geest Bruno G. , Hoogenboom Richard
Published: August 2023

In this work, the straightforward synthesis of amphiphilic zwitterionic bioderived block copolymers (BCPs) using glutamic acid (Glu) and cholesterol (Chol) as building blocks are reported. The previously established Glu‐derivative NBoc‐Glu‐OtBu‐methacrylate (NBoc‐Glu‐OtBu‐MA) serves as hydrophobic precursor for the zwitterionic block, while a mostly unexplored cholesteryl‐derived methacrylate monomer (Chol‐MA) with increased side chain flexibility functions as the hydrophobic block. In the first step, NBoc‐Glu‐OtBu‐MA is polymerized via reversible addition‐fragmentation chain‐transfer (RAFT) polymerization. Afterward, the linear polymer is chain‐extended with Chol‐MA, yielding P(NBoc‐Glu‐OtBu‐MA)n‐b‐(Chol‐MA)m BCPs with varying block ratios. After deprotection under acidic conditions, polymers with a block weight ratio of 87:13 (Glu‐OH‐MA:Chol‐MA) readily assemble into polymeric nanoparticles (NPs) of a desirable size below 100 nm diameter, making them good candidates for biomedical applications. The experimental results are supported using computations of the partition coefficients and machine learning models for the prediction of the polymer densities of the different BCPs. In addition, high (up to 20 wt.%) loading of the hydrophobic anti‐cancer drug 6‐mercaptopurine (6‐MP) is achieved in these NPs during the assembly process. The cytostatic activity of 6‐MP NPs is demonstrated in vitro on MDA‐MB‐231 breast cancer cells. These results emphasize the potential of amphiphilic zwitterionic bioderived NPs for the delivery of hydrophobic drugs.
Engineering Nanotrap Hydrogel for Immune Modulation in Wound Healing
Authors: Yang Xiguang , Guo Dandan , Ji Xiaotian , Shi Changying , Luo Juntao
Published: August 2023

Imbalanced immune regulation leads to the abnormal wound healing process, e.g., chronic unhealing wound or hypertrophic scar formation. Thus, the attenuation of the overflowing inflammatory factors is a viable approach to maintain the homeostatic immune regulation to facilitate normal wound healing. A versatile telodendrimer (TD) nanotrap (NT) platform is developed for efficient biomolecular protein binding. The conjugation of TD NT in size‐exclusive biocompatible hydrogel resin allows for topical application for cytokine scavenging. Fine‐tuning the TD NT density/valency in hydrogel resin controls resin swelling, optimizes molecular diffusion, and improves cytokine capture for effective immune modulation. The hydrogel with reduced TD NT density allows for higher protein/cytokine adsorption capacity with faster kinetics, due to the reduced barrier of TD NT nano‐assembly. The positively charged TD NT hydrogel exhibits superior removal of negatively charged proinflammatory cytokines from the lipopolysaccharide (LPS, a potent endotoxin) primed immune cell culture medium. The negatively charged TD NT hydrogel removes positively charged anti‐inflammatory cytokines efficiently from cell culture medium. TD NT hydrogel effectively constrains the local inflammation induced by subcutaneous LPS injection in mice. These results indicate the great potential applications of the engineered TD NT hydrogel as topical immune modulatory treatments to attenuate local inflammation.
Azobenzene‐Containing Liquid Crystalline Twisted Ribbons via Polymerization‐Induced Hierarchical Self‐Assembly
Authors: Deng Zichao , Sun Yalan , Guan Song , Chen Aihua
Published: August 2023

Polymerization‐induced self‐assembly incorporating liquid crystallization, as a polymerization‐induced hierarchical self‐assembly (PIHSA) method to produce polymeric particles with anisotropic morphologies facilely and efficiently, has drawn wide attention recently. However, the means of regulating the morphologies of liquid crystalline (LC) polymer assemblies still need to be explored. Herein, a route is presented to fabricate the twisted ribbons via PIHSA containing azobenzene based on poor reversible addition‐fragmentation chain transfer (RAFT) control, called poorly controlled PIHSA. Cyano‐4‐(dodecylsulfanylthiocarbonyl)sulfanyl pentanoic acid‐2‐(2‐pyridyldithio) ethyl ester is used as the RAFT agent with poor controllability, and the morphological evolution from ribbons to twisted ribbons can be observed in the corresponding PIHSA system. The formation mechanism of the twisted ribbons is studied systematically and the broad molecular weight distribution is considered to be the decisive factor. Moreover, the supramolecular chirality induced by symmetry breaking is also related to the twist of the ribbons. This study enriches the methods of controlling the morphologies of LC polymer particles and is helpful for further clarifying the mechanism of PIHSA.
On the solution of random linear difference equations with Laplace transform method
Authors: Şişman Şeyma , Merdan Mehmet
Published: August 2023

In this study, Laplace transformation, which is very important for solutions to initial value problems, is examined. To solve the initial value problem of a discrete‐time equation, Laplace implements the conversion method. Here, Laplace transformation is used to obtain an approach to the solutions of random difference equations formed by randomizing components of deterministic difference equations. For random behavior of linear difference equations under random effects, uniform, geometric, binomial, Poisson, and Bernouilli distributions are used, and approximate expected value, variance, standard deviation, and confidence interval of equations obtained by Laplace transformation are calculated. The results were obtained through the Maple package program.
A generalized local fractional LWR model of vehicular traffic flow and its solution
Authors: Pokhriyal Bhawna , Goswami Pranay
Published: August 2023

In this study, a generalized nonlinear local fractional Lighthill‐Whitham‐Richards (LFLWR) model has been developed. The local fractional variational iteration method (LFVIM) solves and analyzes the proposed model. Numerous works have been described in the past to address linear LWR and linear LFLWR models. This research highlighted on generalized nonlinear LFLWR model, and LFVIM is employed to derive non‐differentiable solutions of the suggested model. The existence and uniqueness of the solution of LFLWR model have also been established. Furthermore, several exemplary instances are discussed to demonstrate the success of implementing LFVIM to the proposed model. The numerical simulations for each of the cases have also been shown. Additionally, the obtained solutions of the suggested model have been compared with the solutions of the classical LWR model with non‐differentiable conditions in few examples. The study demonstrates that the employed iterative scheme is quite efficient and can be utilized to obtain the non‐differentiable solution to the proposed generalized nonlinear LFLWR traffic flow model.
Spinal cord motion and CSF flow in the cervical spine of 70 healthy participants
Authors: Beltrán Saúl , Reisert Marco , Krafft Axel J. , Frase Sibylle , Mast Hansjoerg , Urbach Horst , Luetzen Niklas , Hohenhaus Marc , Wolf Katharina
Published: August 2023

Pulsatile spinal cord and CSF velocities related to the cardiac cycle can be depicted by phase‐contrast MRI. Among patients with spontaneous intracranial hypotension, we have recently described relevant differences compared with healthy controls in segment C2/C3. The method might be a promising tool to solve clinical and diagnostic ambiguities. Therefore, it is important to understand the physiological range and the effects of clinical and anatomical parameters in healthy volunteers. Within a prospective study, 3D T2‐weighted MRI for spinal canal anatomy and cardiac‐gated phase‐contrast MRI adapted to CSF flow and spinal cord motion for time‐resolved velocity data and derivatives were performed in 70 participants (age 20–79 years) in segments C2/C3 and C5/C6. Correlations were analyzed by multiple linear regression models; p < 0.01 was required to assume a significant impact of clinical or anatomical data quantified by the regression coefficient B. Data showed that in C2/C3, the CSF and spinal cord craniocaudal velocity ranges were 4.5 ± 0.9 and 0.55 ± 0.15 cm/s; the total displacements were 1.1 ± 0.3 and 0.07 ± 0.02 cm, respectively. The craniocaudal range of the CSF flow rate was 8.6 ± 2.4 mL/s; the CSF stroke volume was 2.1 ± 0.7 mL. In C5/C5, physiological narrowing of the spinal canal caused higher CSF velocity ranges and lower stroke volume (C5/C6 B = +1.64 cm/s, p < 0.001; B = −0.4 mL, p = 0.002, respectively). Aging correlated to lower spinal cord motion (e.g., B = −0.01 cm per 10 years of aging, p < 0.001). Increased diastolic blood pressure was associated with lower spinal cord motion and CSF flow parameters (e.g., C2/C3 CSF stroke volume B = −0.3 mL per 10 mmHg, p < 0.001). Males showed higher CSF flow and spinal cord motion (e.g., CSF stroke volume B = +0.5 mL, p < 0.001; total displacement spinal cord B = +0.016 cm, p = 0.002). We therefore propose to stratify data for age and sex and to adjust for diastolic blood pressure and segmental narrowing in future clinical studies.
Petrov–Galerkin zonal free element method for 2D and 3D mechanical problems
Authors: Xu Bing‐Bing , Gao Xiao‐Wei
Published: August 2023

In this article, a novel weak‐form zonal Petrov–Galerkin free element method is proposed for two‐ and three‐dimensional linear mechanical problems. By absorbing the advantages of finite block method and strong‐form finite element method, the block mapping technique is used in the free element method. Combining the characteristics of the meshless local Petrov–Galerkin method, the local Petrov–Galerkin formulation based on the zonal free element method is formed at last. Besides, the local integral domain selected in the local collocation element is circular or spherical to simplify programming. The transformation of the local integral domain between the physical and normalized spaces is given for two‐ and three‐dimensional problems. The comparison of accuracy and convergence between the new proposed Petrov–Galerkin method and the conventional methods is carried out. Some challenging examples including fracture mechanics problems and a complex 3D problem are given to validate the convergence and accuracy of the proposed method.
Understanding health‐related quality of life trajectories among older adults with diabetes mellitus: Mixed methods research
Authors: Park Sunhee , Lee Taewha
Published: August 2023

Aim

To examine health‐related quality of life trajectories among older adults with diabetes mellitus (DM).

Design

A sequential explanatory mixed method study protocol.

Methods

In the quantitative phase, health‐related quality of life trajectory over 5 years, from 2009 to 2013, of a national representative sample (N = 440) of older adults with DM was analysed using group‐based modelling. Next, a qualitative multiple case study (N = 10) was conducted between November 2017 and April 2018. In the mixed phase, by linking the quantitative and qualitative data, similarities and differences among the four trajectories were identified.

Results

Four distinctive health‐related quality of life trajectories could be distinguished: high then decrease, high stable, medium stable and low then increase. These differed in attitude towards DM, self‐management of DM‐related tasks, comorbidity‐related health‐related quality of life, coping with DM and financial concerns about medical needs.

Relevance to Clinical Practice

Our results help illuminate the heterogeneity of health‐related quality of life trajectories in older adults with DM. This research may help healthcare providers understand the need to assess the HR–QoL comprehensively and promote HR–QoL for older adults with DM.
Monitoring the salt stability and solvent swelling behavior of PAH‐based polyelectrolyte multilayers by quartz crystal microbalance with dissipation
Authors: Konyalı Eymen , Cengiz Hacer Yeşim , Müftüler Ayça , Deligöz Hüseyin
Published: August 2023

This contribution is aimed to examine the layer stability and solvent swelling behavior of polyelectrolyte multilayers (PEMs) obtained from poly(allylamine hydrochloride) (PAH), poly(styrene sulfonic acid sodium salt) (PSS), and poly(acrylic acid) against different salt solutions using Quartz Crystal Microbalance with Dissipation in terms of the solution concentration, charge type of the top layer, and PEM structure. In general, all multilayers remain stable against MgCl2 and NaCl, phosphate buffer saline, ionic liquid, and solvents, namely methanol and heptane, while 4.5‐bilayered PAH‐PSS film displays partial layer decomposition against 1 M NaOCl. Additionally, it is found that the stability of Layer‐by‐Layer (LbL) films remains unaffected by the surface charge type, although variations in the adsorbed and desorbed amounts, as well as the viscoelastic properties, occur during the salt passage and rinsing steps. Along the salt exposure, changes in dissipation (ΔD) significantly increase because of the fast diffusion of ions through the multilayers but return to their initial value after washing. Especially high and reversible ΔD values of the PEMs against methanol are evaluated as swelling in methanol without chemical disintegration. This behavior can be attractive for solvent‐induced release behavior for the LbL‐assembled films or microcapsules.

Highlights

Multilayer stability and solvent swelling of PEMs are discussed using QCM‐D.

PAH‐PSS films have the highest stability against salt solutions.

PAH‐PAA films exhibited significant changes in dissipation values.

PEMs did not show multilayer stability against NaOCl solution.

(PAH‐PSS)5 film was stable and had swelling/de‐swelling capability against methanol.
Mechanosensitive ion channels MSL8, MSL9, and MSL10 have environmentally sensitive intrinsically disordered regions with distinct biophysical characteristics in vitro
Authors: Flynn Aidan J. , Miller Kari , Codjoe Jennette M. , King Matthew R. , Haswell Elizabeth S.
Published: August 2023

Intrinsically disordered protein regions (IDRs) are highly dynamic sequences that rapidly sample a collection of conformations over time. In the past several decades, IDRs have emerged as a major component of many proteomes, comprising ~30% of all eukaryotic protein sequences. Proteins with IDRs function in a wide range of biological pathways and are notably enriched in signaling cascades that respond to environmental stresses. Here, we identify and characterize intrinsic disorder in the soluble cytoplasmic N‐terminal domains of MSL8, MSL9, and MSL10, three members of the MscS‐like (MSL) family of mechanosensitive ion channels. In plants, MSL channels are proposed to mediate cell and organelle osmotic homeostasis. Bioinformatic tools unanimously predicted that the cytosolic N‐termini of MSL channels are intrinsically disordered. We examined the N‐terminus of MSL10 (MSL10N) as an exemplar of these IDRs and circular dichroism spectroscopy confirms its disorder. MSL10N adopted a predominately helical structure when exposed to the helix‐inducing compound trifluoroethanol (TFE). Furthermore, in the presence of molecular crowding agents, MSL10N underwent structural changes and exhibited alterations to its homotypic interaction favorability. Lastly, interrogations of collective behavior via in vitro imaging of condensates indicated that MSL8N, MSL9N, and MSL10N have sharply differing propensities for self‐assembly into condensates, both inherently and in response to salt, temperature, and molecular crowding. Taken together, these data establish the N‐termini of MSL channels as intrinsically disordered regions with distinct biophysical properties and the potential to respond uniquely to changes in their physiochemical environment.
Energy efficient thermochromic smart windows based on polymers and metal oxides
Authors: Chen Guoqi , Zhang Yunting , Chen Yongming , Fu Jun
Published: August 2023

Thermochromic energy efficient windows dynamically regulate building energy exchange by changing their optical transmittance. Recently, thermochromic materials with different chromic mechanisms are developed to fulfill smart window demands. Advanced fabrication technologies for smart windows also lead to building energy efficiency optimization. In this Perspective, representative mechanisms and performances of promising thermochromic systems, including vanadium dioxide, hydrogels, perovskites, ionic liquids, and liquid crystals, are discussed. Furthermore, the emerging technology of radiative cooling is emphasized for future building energy saving. Building temperature regulation and energy saving based on smart windows will make great impacts on the global low carbon economy.