bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Chicken Litter for In Situ Polymerization of Poly(Butylene Succinate) (PBS) Based Polymer Composites
Authors: Nascimento Carla Oliveira , Benites Vinícius De Melo , Cabral‐Albuquerque Elaine Christine de Magalhães , Pinto José Carlos , Fialho Rosana Lopes
Published: April 2023

In the recent years, the growing amounts and incorrect disposal of solid wastes have created serious negative environmental impacts, including land and water pollution. Chicken litter (CL) is a type of solid waste which is generated during chicken production, the appropriate final destination of which is still subject to technical discussion. Because CL is composed mostly of fibers, proteins, carbohydrates, and different minerals, the use of this material as a filler for the manufacture of polymer materials has been suggested. The main objective of the present work is the manufacture of polymer composites in situ polymerization using CL as a filler and succinic acid and 1,4‐butanediol as monomers, considering that the fiber content in CL is ≈20 wt%. The obtained poly(butylene succinate) (PBS) composites are characterized by Fourier transformed infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), degradability in distilled water, and compression analyses. The results show that the addition of CL to the mixture do not affect the course of the polycondensation reaction significantly. Furthermore, compression tests show that the compressive strength of test pieces increases with the CL content.
A fast and practical computation method for magnetic resonance simulators
Authors: Takeshima Hidenori
Published: April 2023

Purpose

This work aims to develop a fast and practical computation method for MR simulations. The computational cost of MR simulations is often high because magnetizations of many isochromats are updated using a small step size on the order of microseconds. There are two types of subsequences to be processed for the simulations: subsequences with and without RF pulses. While straightforward implementations spend most of their time calculating subsequences with RF pulses, there is a method which efficiently reuses the computation for repetitive RF pulses.

Theory and Methods

A new method for efficiently processing subsequences with RF pulses is proposed. Rather than using an iterative update approach, the proposed method computes the combined transition which combines all transitions applied iteratively for each subsequence with RF pulses. The combined transition is used again when the same subsequence is used later. The combined transitions are cached and managed using a least recently used algorithm.

Results

The proposed method was found to accelerate the simulation by ˜20 times when 3.9 million isochromats were simulated using spin‐echo sequences. Even on a laptop computer, the proposed method was able to simulate these sequences in ˜3.5 min.

Conclusion

An efficient method for simulating pulse sequences is proposed. The proposed method computes and manages combined transitions, making MR simulation practical on a wide range of computers, including laptops.
Automated acoustic detection of river herring (Alewife and Blueback Herring) spawning activity
Authors: Staples Amber , Legett Henry D. , Deichmann Jessica L. , Heggie Keira , Ogburn Matthew B.
Published: April 2023

Objective

We used passive acoustic monitoring (PAM) and automatic detection of spawning splashes to examine the timing and environmental drivers of spawning in river herring (Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis).

Methods

Acoustic recordings of spawning splashes were collected from March to May 2021 in the Choptank River, Maryland, using an AudioMoth recorder. Recordings were analyzed using a random forest model on the Rainforest Connection ARBIMON platform to determine hourly presence–absence of splashes.

Result

At a seasonal scale, our results suggested two peaks in spawning activity: early March and mid-April, corresponding with the known phenologies of Alewife and Blueback Herring. Hourly patterns in spawning activity suggested distinct diel cycles, with spawning most concentrated at dawn. In contrast, sonar fish counts collected for 1 week during the season indicated that migration occurred throughout daylight hours. We also found a potential relationship between spawning activity and the presence of great blue herons Ardea herodias.

Conclusion

Overall, our results demonstrate that PAM can be an efficient and affordable method for studying the spawning ecology of anadromous fish.
Current nutrition assessment practice: A 2022 survey
Authors: Guenter Peggi , Blackmer Allison , Malone Ainsley , Phillips Wendy , Mogensen Kris M. , Becker Patricia
Published: April 2023

Background

Malnutrition remains a significant problem in patients with acute or chronic illnesses. Nutrition assessment is an important component in detecting malnutrition; but not always performed using a standardized tool. This survey on nutrition assessment evaluates current clinical practices on the assessment, diagnosis, and treatment of malnutrition.

Methods

This 2022 survey of US‐based nutrition clinicians collected data on assessment parameters used in hospitals, long‐term care facilities, and the home care setting.

Results

A total of 686 surveys were available for analysis. Ninety‐seven percent of adult and 91% of pediatric responding clinicians indicated that a dietitian completed the assessment. Parameters used most frequently among adult clinician respondents included nutrient intake, current weight, and weight history, those used by pediatric clinician respondents included nutrient intake, weight‐for‐age z score, and weight‐for‐length/height z score. Eighty‐nine percent of adult clinicians in all care settings and 85% of pediatric clinicians use the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition Indicators of Malnutrition (AAIM). Respondents reported malnutrition rates of 32%–40% for adults and 4%–30% for pediatric patients, depending on the setting. Appropriate interventions for those with malnutrition (as perceived by the survey respondents) were ordered 70% of the time.

Conclusion

This survey demonstrated significant use of the AAIM by both adult and pediatric clinicians across care settings. Reported malnutrition rates are consistent with others published in the literature. The authors suggest that quality improvement efforts should focus on the 30% of patients with malnutrition but without a reported appropriate nutrition intervention.
They patronize herbal medicine, coincidence or planned behaviour: A case of hypertensive patients in Tamale?
Authors: Iddrisu Mohammed , Doat Abdul Razak , Abdulai Abdul Malik , Wuni Abubakari
Published: April 2023

Aim

This study assessed, if use of herbal medicine (HM) among hypertensive patients is coincidence or planned.

Design

Cross‐sectional survey.

Methods

The study used a cross‐sectional survey for collection of data from four (4) herbal medicine clinics in the Tamale metropolis in northern Ghana.

Results

The final or overall regression model was significant at R2 = 0.350, F(7, 214) = 16.464, p < 0.001. No sociodemographic characteristic predicted herbal medicine use. Only religion and educational level were associated with herbal medicine use. Attitude (p = 0.002), subjective norms (p = 0.001) and behavioural intention (p = 0.000) significantly predicted HM use.

Public contribution

Data were collected from respondents only after they had verbally given free and informed consent to take part in the study. The results of this study therefore showed that herbal medicine use among these patients is not coincidence but planned. Health professionals by this study should appreciate the effect of religion and educational background in their health education on Herbal Medicines.
Barriers and enabling factors for workplace integration of internationally qualified nurses: A qualitative study of perceptions of German nurses
Authors: Roth Catharina , Breckner Amanda , Wensing Michel , Mahler Cornelia , Krug Katja , Berger Sarah
Published: April 2023

Aim

Examine perceptions of nurses who obtained a recognised nursing qualification in Germany about the integration of internationally qualified nurses (IQN) in the German nursing workforce.

Design

Qualitative interview study.

Methods

Semi‐structured interviews with 21 state‐qualified nurses who had graduated from a German nursing program were conducted either face‐to‐face or by telephone. Nurses were selected using the purposive sampling method. Additionally, to reach a sufficient sample size, snowball sampling was applied. Each interview was pseudonymized and transcribed. Transcripts were coded according to Qualitative Content Analysis with data structured into themes and sub‐themes. The study was reported according to the Consolidated Criteria for Reporting Qualitative Studies (COREQ) checklist for qualitative research.

Results

Two main themes including sub‐themes were identified: (a) Enabling Factors to Workplace Integration: motivated nursing team, structured orientation program, support by a preceptor, additional practical skills and specific language training and (b) Barriers to Workplace Integration: lack of language proficiency, cultural differences, othering and racism/discrimination. The findings of the study suggest that working in a diverse workplace can be challenging, it is therefore important for successful integration to recognise not only the experiences of IQN but also the perceptions of nurses who work with internationally qualified peers.

No patient or public contribution.

Registration number

The study has been prospectively registered (27 June 2019) at the German Clinical Trial Register (REDACTED).
Compressible zinc‐ion hybrid supercapacitor and piezoresistive sensor based on reduced graphene oxide/polypyrrole modified melamine sponge
Authors: Wen Meichen , Yu Xiuwen , Yang Chao , Qiu Jianhui , Zang Limin
Published: April 2023

Compressible energy storage devices are very promising in wearable electronics owing to their stable performance under different compressed strains. Melamine sponge (MS) is modified by reduced graphene oxide (rGO) and polypyrrole (PPy) to obtain the compressible positive electrode (PPy/rGO@MS) in this work. Then a compressible zinc‐ion hybrid supercapacitor (CZHS) with a novel construction is designed by sandwiching the PPy/rGO@MS positive electrode between two Zn foils to improve the utilization of active materials. The CZHS with an operating voltage within 0.2–1.8 V exhibits high specific capacity of 129.8 mAh g−1, energy density of 103.8 Wh kg−1, capacity retention of 72.0% after 15,000 GCD cycles. Besides, capacity retention of the CZHS is 90.9% after 3000 compression/release cycles with a compressive strain of 40%. The results indicate the CZHS has both outstanding electrochemical performance and high compressibility. The charge storage mechanism of the Zn//PPy/rGO@MS system is also investigated by electrochemical analysis and density functional theory. Taking advantage of the compressibility and sensitive resistance change of the PPy/rGO@MS composite, a piezoresistive sensor with similar construction as the CZHS is fabricated. This work provides an effective strategy for fabricating compressible energy storage device and piezoresistive sensor with high performance.
Students engagement in remote‐learning during the Covid‐19 crisis: The role of the support provided to teachers and the parent–teacher relationship
Authors: Gershy Naama , Katz Idit
Published: April 2023

The global COVID‐19 pandemic has suddenly forced hundreds of millions of teachers to shift from in‐person to remote teaching. This abrupt change from classroom to home as the context for learning has required teachers to make substantial modifications and adjustments to engage their students in learning. This study was designed to explore what characterizes those teachers who better engage their students in learning. Based on the theoretical assumptions of Self Determination Theory (SDT), we asked whether teachers' experience of school as a need‐satisfying environment, their teaching style, efficacy, and their relations with the students' parents, impact students' engagement in remote learning. Three hundred and thirty‐six Israeli teachers completed self‐report questionnaires on need satisfaction, teaching efficacy, teaching style, parent–teacher relationship, and students' engagement during Israel's May 2020 school shutdown. The results showed that teachers' experience of need‐satisfaction emerged as a resource for teachers' efficacy, teaching style, and ability to create and maintain a positive relationship with parents. A positive relationship between parents and teachers, in turn, was associated with higher students' engagement in remote learning even when statistically controlling for socioeconomic status or grade level. These results highlight the critical role of the parent–teacher relationship in engaging students while learning remotely and suggest that the support provided to both teachers and parents can reduce disparities in students' engagement and promote engagement with learning under challenging contextual circumstances.
Measuring the impact of a positive psychology course at a Thai university: Addressing student well‐being in challenging times
Authors: McDonald Ian , Nanni Alexander
Published: April 2023

Even before the onset of the COVID‐19 pandemic, researchers had raised concerns about the mental health of youth worldwide. One response has been the development of positive psychology interventions (PPIs) designed to enhance well‐being. This study, conducted at a Thai university, investigated the impact of an online positive psychology course containing several PPIs on student well‐being as measured by the EPOCH Measure of Adolescent Well‐Being, the Satisfaction With Life Scale (SWLS), and Subjective Happiness Scale. The scores of the students in the positive psychology course (n = 84) increased in all areas measured, with statistically significant increases in the Perseverance, Optimism, and Happiness subscales of the EPOCH. Meanwhile, the scores of the control group (n = 105) decreased in all but two areas, with statistically significant decreases in the SWLS and Optimism. These findings suggest that teaching PPIs online can positively impact students' well‐being.
Advances in proteomic phenotyping of microglia in neurodegeneration
Authors: Sunna Sydney , Bowen Christine A. , Ramelow Christina C. , Santiago Juliet V. , Kumar Prateek , Rangaraju Srikant
Published: April 2023

Microglia are dynamic resident immune cells of the central nervous system (CNS) that sense, survey, and respond to changes in their environment. In disease states, microglia transform from homeostatic to diverse molecular phenotypic states that play complex and causal roles in neurologic disease pathogenesis, as evidenced by the identification of microglial genes as genetic risk factors for neurodegenerative disease. While advances in transcriptomic profiling of microglia from the CNS of humans and animal models have provided transformative insights, the transcriptome is only modestly reflective of the proteome. Proteomic profiling of microglia is therefore more likely to provide functionally and therapeutically relevant targets. In this review, we discuss molecular insights gained from transcriptomic studies of microglia in the context of Alzheimer's disease as a prototypic neurodegenerative disease, and highlight existing and emerging approaches for proteomic profiling of microglia derived from in vivo model systems and human brain.
The Resilience Scale for Parents of Children with Cancer: Scale development and psychometric evaluation
Authors: Önal Gözde , Huri Meral , Karakükçü Musa , Demir Hacı Ahmet
Published: April 2023

Objective

This study aimed to develop a Resilience Scale for Parents of Children with Cancer (RSP‐CC) designed specifically for parents of children with cancer and to evaluate its psychometric properties.

Methods

Based on the Resilience Model for Families of Children with Cancer, items were created after an extensive literature review and evaluated through expert consultation and a pilot study. Psychometric evaluation was conducted with the parents of 601 children with cancer in the pediatric hematology oncology services of different hospitals in the Ankara and Kayseri provinces in Turkey.

Results

A 4‐factor structure was illustrated by exploratory factor analysis and confirmed by confirmatory factor analysis, explaining 62.192% of the total variance. In the reliability analysis of the scale, Interclass correlation = 0.993 and Cronbach's alpha = 0.994 were found for the scale. Robust correlation coefficients were found between test‐retest, and the correlation between the two measurements was statistically significant (r = 0.990; p ˂ 0.001). As a result, the validity of a 24‐item scale structure consisting of 4 dimensions was validated.

Conclusions

It may be said that the RSP‐CC meets the necessary criteria to examine the resilience in parents of children aged 0–18 with a cancer diagnosis, and its psychometric properties are reasonable sufficient.
Kinetic evidence in favor of glyoxalase III and against deglycase activity of DJ‐1
Authors: Choi Joonhyeok , Tak Sungho , Jung Hoe‐Myung , Cha Soyoung , Hwang Eunha , Lee Donghan , Lee Joon‐Hwa , Ryu Kyoung‐Seok , Park Chankyu
Published: April 2023

DJ‐1, a protein encoded by PARK7 plays a protective role against neurodegeneration. Since its glyoxalase III activity catalyzing methylglyoxal (MG) to lactate was discovered, DJ‐1 has been re‐established as a deglycase decomposing the MG‐intermediates with amino acids and nucleotides (hemithioacetal and hemiaminal) rather than MG itself, but it is still debatable. Here, we have clarified that human DJ‐1 directly recognizes MG, and not MG‐intermediates, by monitoring the detailed catalytic processes and enantiomeric lactate products. The hemithioacetal intermediate between C106 of 15N‐labeled DJ‐1 (15NDJ‐1) and MG was also monitored by NMR. TRIS molecule formed stable diastereotopic complexes with MG (Kd, 1.57 ± 0.27 mM) by utilizing its three OH groups, which likely disturbed the assay of deglycase activity. The low kcat of DJ‐1 for MG and its MG‐induced structural perturbation may suggest that DJ‐1 has a regulatory function as an in vivo sensor of reactive carbonyl stress.
New method for peptide purification based on selective removal of truncation peptide impurities after SPPS with orthogonal capping
Authors: Wunderlich Hendrik , Alvaro Roque Augusto Castro , Wenschuh Holger , Schnatbaum Karsten
Published: April 2023

Peptide purification by high‐performance liquid chromatography (HPLC) is associated with high solvent consumption, relatively large effort and lack of efficient parallelization. As an alternative, many catch‐and‐release (c&r) purification methods have been developed over the last decades to enable the efficient parallel purification of peptides originating from solid‐phase peptide synthesis (SPPS). However, with one exception, none of the c&r systems has been widely established in industry and academia until today. Herein, we present an entirely new chromatography‐free purification concept for peptides synthesized on a solid support, termed reactive capping purification (RCP). The RCP method relies on the capping of truncation peptides arising from incomplete coupling of amino acids during SPPS with a reactive tag. The reactive tag contains a masked functionality that, upon liberation during cleavage from the resin, enables straightforward purification of the peptide by incubation with a resin‐bound reactive moiety. In this work, two different reactive tags based on masked thiols were developed. Capping with these reactive tags during SPPS led to effective modification of truncated sequences and subsequent removal of the latter by chemoselective reaction with a maleimide‐functionalized solid support. By introducing a suitable protecting group strategy, the thiol‐based RCP method described here could also be successfully applied to a thiol‐containing peptide. Finally, the purification of a 15‐meric peptide by the RCP method was demonstrated. The developed method has low solvent consumption, has the potential for efficient parallelization, uses readily available reagents, and is experimentally simple to perform.
Polysilsesquioxane Gate Dielectric Layers Cured by UV Light Irradiation Using Thiol–Ene Reaction for Organic Thin‐Film Transistors
Authors: Nakahara Yoshio , Yamane Ken-ichiro , Nakagami Tomoaki , Uno Kazuyuki , Tanaka Ichiro
Published: April 2023

Polysilsesquioxane (PSQ) is used to make gate dielectric layers with pentacene to create thin‐film transistors (TFTs) by incorporating 3‐mercaptopropyl functional groups for UV light‐initiated thiol–ene polymerization with vinyl‐containing cross‐linkers. The dielectric constant (ε) of the polymerized PSQ films is controlled by the ratio of 3‐mercaptopropyl groups. When the 3‐mercaptopropyl group comprises 20%, it yields a polymerized film with a ε of 4.2 ± 0.2; upon decreasing this proportion to 10%, the ε for the subsequent film became 3.5 ± 0.2. The hole mobility of the fabricated pentacene TFTs is observed to increase as ε decreases, reaching a maximum of 0.96 cm2 V−1 s−1.
Synthesis of CoFe2O4 Nanomaterials via Sol–Gel Auto‐Combustion Method using Different Chelating Agent, and Its Effects on Magnetic and Dielectric Properties
Authors: Gatchakayala Naresh Babu , Dachuru Rama Sekhara Reddy
Published: April 2023

Herein, the structural and magnetic properties of cobalt ferrite (CoFe2O4 [CFO]) nanomaterials obtained from sol–gel auto‐combustion method using different chelating agent (tartaric acid, citric acid, and oxalic acid) are reported. The obtained precursors from the different chelating agents are calcined at 500 °C for 5 h. The X‐ray diffraction (XRD) analysis suggests that all the synthesized samples show the single‐phase spinel ferrite structure without existing any secondary impurity phases. The lattice parameter, cell volume, density, crystallite size, and dislocation density are computed for all the synthesized samples utilizing the XRD data. The irregular‐shaped grains morphology with a homogeneous distribution is observed through scanning electron microscopy study. The sample synthesized by using the tartaric acid as a chelating agent shows a high magnetization value, highest coercivity, and highest anisotropy constant (K) when compared to those of other chelating agents. High grain‐boundary activation energy is also observed for the CFO nanomaterials obtained from the tartaric acid as a chelating agent.
Indirect Orbital Hybridization Induced by Nonbonding Interaction at Li‐Intercalated IrO2 Monolayers for Oxygen Evolution Reaction
Authors: Shan Yun , Gao Qian , Zhu Yuan , Wang Ying , Wu Shuyi , Li Tinghui
Published: April 2023

The development of excellent catalysts with high reactive activity remains a significant challenge for overcoming the sluggish oxygen evolution reaction (OER). Different from other catalysts, herein, a feasible Li intercalation strategy is suggested to regulate the spin‐resolved electronic structures of 2D‐layered IrO2 nanostructures for improving their reactive activity. When some Li ions are intercalated into the layered IrO2 materials, the spin splitting at Ir‐5d orbitals occurs, leading to an obvious reduction in the relative activation energies at OER. The detailed analysis about spin‐resolved electronic structures demonstrates that the intercalated Li ions can provide some 1s electrons to the O‐2p orbitals via a weak bonding interaction, for which the electronic occupation at Ir‐5d orbitals becomes asymmetric, giving rise to a spin polarization. More interestingly, the catalytic activity is enhanced with Li‐intercalation concentration. Herein, a new door is opened to improve OER performance by an intriguing indirect orbital hybridization.
Fast Quantifier of High‐Dimensional Frequency Entanglement through Hong–Ou–Mandel Interference
Authors: Hong Ling , Zhang Yuning , Chen Yuanyuan , Chen Lixiang
Published: April 2023

High‐dimensional frequency entanglement is an enabling resource in quantum technology due to its high information capacity and error resilience. A concise yet efficient method for precisely quantifying its dimensionality remains an open challenge, owing to the difficulties for performing required superposition measurements in energy‐time domains, and the complexity associated with full quantum state tomography that scales unfavorably with dimensions. With the assistance of Hong–Ou–Mandel experiment that performs a Fourier transform between the entangled photons in terms of joint spectral intensities and the quantum interference in terms of biphoton temporal coincidences, the concept of Shannon dimensionality as a fast quantifier of bipartite continuous frequency entanglement is unlocked. This quantitative technique reveals the complete distribution of frequency entanglement but without suffering from any limitation of modal capacity of the detection geometry. These results may significantly facilitate the use of quantum interference for characterizing the high‐dimensional entanglement nature by avoiding some stringent conditions.
Deterministic algorithms for the Lovász local lemma: Simpler, more general, and more parallel
Authors: Harris David G.
Published: April 2023

The Lovász local lemma (LLL) is a keystone principle in probability theory, guaranteeing the existence of configurations which avoid a collection of “bad” events which are mostly independent and have low probability. A seminal algorithm of Moser and Tardos (J. ACM, 2010, 57, 11) (which we call the MT algorithm) gives nearly‐automatic randomized algorithms for most constructions based on the LLL. However, deterministic algorithms have lagged behind. We address three specific shortcomings of the prior deterministic algorithms. First, our algorithm applies to the LLL criterion of Shearer (Combinatorica, 1985, 5, 241–245); this is more powerful than alternate LLL criteria and also leads to cleaner and more legible bounds. Second, we provide parallel algorithms with much greater flexibility. Third, we provide a derandomized version of the MT‐distribution, that is, the distribution of the variables at the termination of the MT algorithm. We show applications to non‐repetitive vertex coloring, independent transversals, strong coloring, and other problems.
Rapidly Progressing Necrotic Hand Ulcer in a Patient with Angioimmunoblastic T-Cell Lymphoma
Authors: Wang Hua Xian Elizabeth , Ooi Xue Ting , Lim Kok Hing , Oh Choon Chiat
Published: April 2023

Mucormycosis is a fungal infection caused by opportunistic fungi of the phylum Glomeromycota, subphylum Mucormycotina. In developed countries, it affects patients with haematological malignancies undergoing chemotherapy and those who have received allogenic stem cell transplants, while in developing countries it is seen in those with uncontrolled diabetes mellitus. Herein, we report a case of cutaneous mucormycosis in a 67yo Chinese gentleman with background of angioimmunoblastic T cell lymphoma (AITL) on chemotherapy. We also share the clinicopathological findings of this and correlate these findings with those present in the current literature. Finally, we outline treatment options and prognosis of cutaneous mucormycosis.
Total Synthesis of Natural Products Dysideolide A and B
Authors: Anil Talakokkula , Karunakar Baikadi , Ranganath Prathapagiri L. N. , Narsaiah Akkirala Venkat
Published: April 2023

The total synthesis of marine sponge products dysideolide A and B have been achieved in stereo controlled manner. The butenolide and pentenolide lactones are consisting of sensitive, α,β‐unsaturated cis‐olefin functional group and which was installed by Still‐Gennari olefination with ketone. The synthesis starts from D‐mannitol and D‐ribose respectively. Notable features of the synthesis are Z‐selective Still‐Gennari olefination, Pinnick oxidation and Shiina macrolactonization.
Mannich Reaction: Review of Amine‐Functionalized Lignin Derivatives and Their Applications
Authors: Jayaramudu Tippabattini , Varaprasad Kokkarachedu , Adamus Grazyna , Amber Jennings Jessica , Bumgardner Joel D.
Published: April 2023

In recent years naturally resourced materials have played a significant role in many applications ranging from biomedical to automotive applications. Among them, lignin has received much attention towards these applications owing to its abundance and readily modified chemical structures. Recent research studies have focused on various chemical modifications of lignin, including the increasingly popular Mannich reaction that aminates the lignin structure to expand the applicability of lignin in advanced fields. This article reviews the recent Mannich reaction‐based lignin developments with different types of amines used in lignin modifications and discusses how the reaction enhances functionality in engineering, biomedical and environmental technology applications.
An Efficient Solvothermal Method for One‐Pot Batch Simultaneous Synthesis of OZPMs and DHPMs**
Authors: Chen Dan , Pan Xin‐Guang , An Yan , Zheng Lu , Liu Yu , Wang Shi‐Fan
Published: April 2023

An efficient solvothermal method for one pot batch simultaneous synthesis of oxazolopyrimidines and dihydropyrimidinones has been developed in a small amount of lactic acid without any additional catalysts and additives for the first time. Ten oxazolopyrimidines and nine novel dihydropyrimidinones were simultaneously synthesized by the condensation of 1, 3‐dicarbonyl compounds, aromatic aldehydes and β‐hydroxyethylurea in the solvothermal reactors. All products were obtained in high yields and characterized by IR, 1H NMR, 13C NMR, and HR‐MS. Further, the structure of oxazolopyrimidine has been undoubtedly identified with the means of single crystal X‐ray diffraction.
Novel Azapodophyllotoxin Induces DNA Cleavage via Groove Binding: An Advancement in Exploration of Anticancer Activity of a Known Inhibitor of Tubulin Polymerization and Topoisomerase
Authors: Gupta Smruti , Kumar Ajay , Ghosh Sujit Kumar
Published: April 2023

The present study embodies exploration of new potential targets for bioactive azapodophyllotoxins (AZP) that have been mainly considered as inhibitor of tubulin polymerization and topoisomerases. The interaction of a novel AZP, HTDQ, with potential target DNA (calf thymus DNA) has been investigated alongwith its mechanism of action by using combined biophysical spectroscopic techniques and in silico approach. The steady state absorption and fluorescence studies highlights binding interaction of HTDQ with the nucleic acid and the value of Stern Volmer quenching constant (8.07×103 L mol−1) hints towards minor groove binding interaction. The KI quenching studies, helix melting and viscosity measurements further supports our speculation and is substantiated by fluorescence displacement assay using standard minor groove binder, Hoechst 33258. The conformational alterations due to HTDQ‐ctDNA binding is evident from circular dichroism studies and have been further validated from the in silico molecular docking and molecular dynamics simulation studies. Additionally, with a view to get thorough understanding of the mechanism, the DNA cleavage studies have been performed using gel electrophoresis that proved instrumental in determining the ability of HTDQ to damage the structural homogeneity of the nucleic acid.
Preparation of Chitosan Hydrogels Containing Ruhemann's Purple and Zn(II) Complex of Ninhydrin with Antibacterial and Antioxidant and Photodynamic Therapy Properties
Authors: Doosti Fatemeh , Karimi Ali Reza , Hadizadeh Mahnaz
Published: April 2023

In this study, homogeneous hydrogels based on chitosan containing ninhydrin derivatives, including Ruhemann's purple (RP) and its Zn(II) Schiff base chelate of indane‐l,3‐dione‐2‐imine‐N‐acetic acid (Zn(II)IDIA), as photosensitizers have been synthesized with the potential of photodynamic therapy (PDT) applications. Ninhydrin is a valuable organic compound that exhibits bacteriostatic, virucidal, and anti‐diabetogenic properties. This study describes how the use of ninhydrin is a viable option for the investigation of in vitro PDT activities. The hydrogels were prepared through chemical cross‐linking using glutaraldehyde and loaded with water‐soluble photosensitizers. According to the results, the hydrogels demonstrated a three‐dimensional (3D) porous morphology, remarkable singlet oxygen generation, antibacterial activity, and good mechanical strength. The results of the cell viability assay illustrated their excellent biocompatibility and safety. All the information in this study supports the capability of the hydrogels containing RP and Zn(II)IDIA for PDT treatment.
Naphthalene‐1,2‐dione and indoline‐2,3‐dione as Convenient Ligands to Prepare Mixed Ligand Complexes of Mn, Cu And Cd: Synthesis, Spectroscopic Characterization, DFT Study and Antibacterial Activity
Authors: Zayed Ehab M. , Abd ElSallam Hayam A. , Fathala Maha I. , Sroor Farid M.
Published: April 2023

Mixed ligand (L1L2) (where L1=naphthalene‐1,2‐dione and L2=indoline‐2,3‐dione) and its Mn(II), Cu(II) and Cd(II) complexes (3 a, 3 b, and 3 c, respectively) were prepared and described using analytical analysis, FT‐IR, UV–Vis, magnetic measurements, XRD‐diffraction and molar conductivity. Moreover, the structural properties of the mixed ligand complexes were investigated using mass spectrometry and elemental analysis. These complexes are expected to have octahedral molecular geometry depending on the electronic spectra and magnetic susceptibility tests. The two mixed ligands (L1L2) are bivalent ligands with two oxygen atoms. As an example, the quantum chemical properties, bond lengths, and bond angles were discussed for the Cu(II) complex. The Gaussian09 program was used to optimize the structural formula for the investigated ligand. The energy gaps and other essential theoretical properties were calculated using the DFT/B3LYP approach. The prepared mixed ligand complexes 3 a, 3 b, and 3 c were evaluated for their antibacterial properties. These complexes were tested against both Gram‐positive bacteria (Bacillus subtilis and Staphylococcus aureus) and Gram‐negative bacteria (Escherichia coli and Pseudomonas aeruginosa) using the agar diffusion method. The organic ligands were observed to be less biologically active than the targeted complexes as antimicrobial agents. According to molecular docking, the title compounds have a positive interaction with the crystal structures of Escherichia coli (3HUM), Staphylococcus aureus (5 M18), Bacillus subtilis (5ZW4), and Pseudomonas aeruginosa (4WEL).
N‐Aroyl‐N′‐(1‐Naphthyl)‐N′′‐aryl guanidines as a New Entry to Urease Inhibitors: Synthesis, Kinetic Mechanism, Molecular Docking and MD Simulation Studies
Authors: Tahira Sarwat , Saeed Aamer , Farid Aftab , Channar Pervaiz Ali , Tehzeeb Arfa , Abbas Qamar , Abdalla Mohnad
Published: April 2023

A series of novel guanidines (6 a–j) was synthesized from corresponding thioureas using catalytic mercuric chloride in DMF. The synthesized compounds were characterized by spectroscopic techniques and appraised for Jack Bean Urease (JBU) inhibition. All compounds (6 a–j) exhibited strong potential against JBU whilst compound6 b(IC50=0.0155±0.00087 μM) and6 e(IC50=0.0091±0.00036 μM) displayed excellent urease inhibition compared to thiourea (IC50=18.27 μM) used as reference. The kinetic mechanism analyzed by Lineweaver‐Burk plots revealed that6 bis a mixed‐type inhibitor while6 eis a non‐competitive inhibitor. Thus, compounds6 eand6 bcan serve as a structural model for the designing of super‐effective urease inhibitors. Binding affinity and interaction ofN‐aryl guanidine analogs were evaluated through molecular docking studies. To evaluate the residual flexibility of receptor through MD simulation, RMSD and RMSF graphs were evaluated to determine the protein structural behavior. It is implied that compound6 ecan serve as a novel molecular template to medicinal chemists for designing more potent urease inhibitors.
Nanoclusterzyme for Dual Colorimetric Sensings: A Case Study on [Au14(Dppp)5I4]2+
Authors: Zhao Hongliang , You Qing , Zhu Wanli , Li Jin , Deng Haiteng , Li Man‐Bo , Zhao Yan , Wu Zhikun
Published: April 2023

The enzymatic activity of atomically precise metal nanoclusters has recently been recognized; however, the number of nanoclusterzymes is very small. Besides, the applications of nanoclusterzyme wait to be explored. Herein, a novel nanoclusterzyme is synthesized and its structure is majorly resolved by single‐crystal X‐ray diffraction and mass spectrometry, which reveal that the nanocluster consists of an Au13 icosahedron capped by an exterior shell including four I, three Dppp (1,3‐bis(diphenylphosphino) propane) ligands, and a rarely reported Dppp‐Au‐Dppp handle staple, which contributes a lot to the enzyme activity of [Au14(Dppp)5I4]2+ nanocluster. The as‐obtained nanocluster can catalyze oxygen to O2•− under visible light irradiation with a specific activity up to 0.182 U·mg−1 and lead to the blue color of 3,3′,5,5′‐tetramethylbenzidine (TMB) in both solution and solid states. With the addition of acetylcholinesterase (AChE), the blue color of (Au14 + TMB) solution system disappears due to the nanoclusterzyme activity inhibition, but the further addition of organophosphorus pesticides (OPs) into the above mixture can restore the nanoclusterzyme and recover the blue color. Based on the color turn‐off and on, the various nanoclusterzyme‐containing systems are used to colorimetrically sense AChE and OPs with the detection limits reaching 0.04 mU·mL−1 and 0.02 ng·mL−1, respectively.
Second Near‐Infrared Plasmonic Nanomaterials for Photoacoustic Imaging and Photothermal Therapy
Authors: Yan Tingjun , Su Mengyao , Wang Zhimin , Zhang Jiatao
Published: April 2023

Photoacoustic imaging (PAI) and imaging‐guided photothermal therapy (PTT) in the second near‐infrared window (NIR‐II, 1000–1700 nm) have received increasing attention owing to their advantages of greater penetration depth and higher signal‐to‐noise ratio. Plasmonic nanomaterials with tunable optical properties and strong light absorption provide an alternative to dye molecules, showing great prospects for phototheranostic applications. In this review, the research progress in principally modulating the optical properties of plasmonic nanomaterials, especially affecting parameters such as size, morphology, and surface chemical modification, is introduced. The commonly used plasmonic nanomaterials in the NIR‐II window, including noble metals, semiconductors, and heterostructures, are then summarized. In addition, the biomedical applications of these NIR‐II plasmonic nanomaterials for PAI and PTT in phototheranostics are highlighted. Finally, the perspectives and challenges for advancing plasmonic nanomaterials for practical use and clinical translation are discussed.
Stratified Oxygen Vacancies Enhance the Performance of Mesoporous TiO2 Electron Transport Layer in Printable Perovskite Solar Cells
Authors: Liu Jiale , Li Sheng , Qiu Zexiong , Liu Yang , Qiu Cheng , Zhang Wenhao , Qi Jianhang , Chen Kai , Wang Wei , Wang Chaoyang , Cui Zhaozhen , Su Yaqiong , Hu Yue , Mei Anyi , Han Hongwei
Published: April 2023

The low electrical conductivity and the high surface defect density of the TiO2 electron transport layer (ETL) limit the power conversion efficiency (PCE) of corresponding perovskite solar cells (PSCs). Here, the conductivity and defect modulation of the mesoporous TiO2 (mp‐TiO2) ETL via oxygen vacancy (OV) management by the reduction and oxidation treatment are reported. Reduction treatment via reducing agent introduces abundant OVs into the TiO2 nanocrystalline particles on the surface and at the subsurface. The following oxidation treatment via hydrogen peroxide removes the surface OVs while remains the subsurface OVs, resulting in stratified OVs. The stratified OVs improve the conductivity of TiO2 ETL by increasing carrier donors and decrease nonradiative centers by reducing surface defects. Such synergy ensures the capability of mp‐TiO2 as the well‐performed ETL with improved energy level alignment, suppressed interface recombination, enhanced carrier extraction, and transport. As a result, printable hole‐conductor‐free carbon‐based mesoscopic PSCs based on the modulated mp‐TiO2 ETL demonstrate a highest reported PCE of 18.96%.
Revealing Site Occupancy in a Complex Oxide: Terbium Iron Garnet
Authors: Rosenberg Ethan , Bauer Jackson , Cho Eunsoo , Kumar Abinash , Pelliciari Jonathan , Occhialini Connor A , Ning Shuai , Kaczmarek Allison , Rosenberg Richard , Freeland John W. , Chen Yu‐Chia , Wang Jian‐Ping , LeBeau James , Comin Riccardo , de Groot F. M. F. , Ross Caroline A
Published: April 2023

Complex oxide films stabilized by epitaxial growth can exhibit large populations of point defects which have important effects on their properties. The site occupancy of pulsed laser‐deposited epitaxial terbium iron garnet (TbIG) films with excess terbium (Tb) is analyzed, in which the terbium:iron (Tb:Fe)ratio is 0.86 compared to the stoichiometric value of 0.6. The magnetic properties of the TbIG are sensitive to site occupancy, exhibiting a higher compensation temperature (by 90 K) and a lower Curie temperature (by 40 K) than the bulk Tb3Fe5O12 garnet. Data derived from X‐ray core‐level spectroscopy, magnetometry, and molecular field coefficient modeling are consistent with occupancy of the dodecahedral sites by Tb3+, the octahedral sites by Fe3+, Tb3+ and vacancies, and the tetrahedral sites by Fe3+ and vacancies. Energy dispersive X‐ray spectroscopy in a scanning transmission electron microscope provides direct evidence of TbFe antisites. A small fraction of Fe2+ is present, and oxygen vacancies are inferred to be present to maintain charge neutrality. Variation of the site occupancies provides a path to considerable manipulation of the magnetic properties of epitaxial iron garnet films and other complex oxides, which readily accommodate stoichiometries not found in their bulk counterparts.
Digital Detection of Single Virus Particles by Multi‐Spot, Label‐Free Imaging Biosensor on Anti‐Reflective Glass
Authors: Nava Giovanni , Casiraghi Luca , Carzaniga Thomas , Zanchetta Giuliano , Chiari Marcella , Damin Francesco , Bollati Valentina , Signorini Lucia , Delbue Serena , Bellini Tommaso , Buscaglia Marco
Published: April 2023

Rapid detection of whole virus particles in biological or environmental samples represents an unmet need for the containment of infectious diseases. Here, an optical device enabling the enumeration of single virion particles binding on antibody or aptamers immobilized on a surface with anti‐reflective coating is described. In this regime, nanoparticles adhering to the sensor surface provide localized contributions to the reflected field that become detectable because of their mixing with the interfering waves in the reflection direction. Thus, these settings are exploited to realize a scan‐free, label‐free, micro‐array‐type digital assay on a disposable cartridge, in which the virion counting takes place in wide field‐of‐view imaging. With this approach we could quantify, by enumeration, different variants of SARS‐CoV‐2 virions interacting with antibodies and aptamers immobilized on different spots. For all tested variants, the aptamers showed larger affinity but lower specificity relative to the antibodies. It is found that the combination of different probes on the same surface enables increasing specificity of detection and dynamic range.
Concentration Phase Separation of Substitution‐Doped Atoms in TMDCs Monolayer
Authors: Wang Shuang , Ding Degong , Li Pai , Sui Yanping , Liu Guanyu , Zhao Sunwen , Xiao Runhan , Tian Chuang , Chen Zhiying , Wang Haomin , Chen Chen , Mu Gang , Liu Yixin , Zhang Yanhui , Jin Chuanhong , Ding Feng , Yu Guanghui
Published: April 2023

The density and spatial distribution of substituted dopants affect the transition metal dichalcogenides (TMDCs) materials properties. Previous studies have demonstrated that the density of dopants in TMDCs increases with the amount of doping, and the phenomenon of doping concentration difference between the nucleation center and the edge is observed, but the spatial distribution law of doping atoms has not been carefully studied. Here, it is demonstrated that the spatial distribution of dopants changes at high doping concentrations. The spontaneous formation of an interface with a steep doping concentration change is named concentration phase separation (CPS). The difference in the spatial distribution of dopants on both sides of the interface can be identified by an optical microscope. This is consistent with the results of spectral analysis and microstructure characterization of scanning transmission electron microscope. According to the calculation results of density functional theory, the chemical potential has two relatively stable energies as the doping concentration increases, which leads to the spontaneous formation of CPS. Understanding the abnormal phenomena is important for the design of TMDCs devices. This work has great significance in the establishment and improvement of the doping theory and the design of the doping process for 2D materials.
A 3D Mathematical Modeling on Meniscus Solidification and Heat Transfer in Continuous Casting Chamfered Mold of Slab
Authors: Zhang Li , Wei Sentai , He Shengping , Zhang Xubin , Wang Qiangqiang
Published: April 2023

Herein, a 3D mathematical model is established to elucidate the meniscus solidification and heat transfer in the chamfered mold. The fluid flow, heat transfer, the solidification of steel, the oscillation of the mold, and the steel–slag interfacial tension are considered, and the meniscus behavior on different longitudinal sections and cross sections is discussed. Under the influence of the upper roll flow, the height of the steel level increases from submerged entry nozzle to narrow face, which affects the distribution of the oscillation mark on the surface of the shell. With the mold chamfer and two new corners, the thickness of the slag film at the corner 1 with angle of 123.7° is the largest, and the shell thickness is the smallest, which is related to the 3D profile of the meniscus near the corner. The largest heat flux is located at 10–14 mm below the initial level of liquid steel and is below 3.0 MW m−2. The heat flux at the corner 1 with small obtuse angle is the smallest on the same cross section, indicating that small obtuse angle near the corner resulted in the low heat transfer.
Dynamic Precipitation of Laves Phase in FeCrAl Alloy with Zr Addition
Authors: Liu Wenbo , Liu Zhe , Liu Huiqun , Zhang Luhuai , Zhang Ruiqian
Published: April 2023

FeCrAl alloy is one of potential candidates for accident‐tolerant‐fuel (ATF)‐cladding materials due to its excellent oxidation and corrosion resistance at accident temperature, combining good mechanical properties at service temperature. Alloying strategy is an important way for improving comprehensive properties of FeCrAl alloy through the precipitation of fine Laves phase. Zr alloying can stabilize the Laves phase due to its lower diffusion coefficient and solubility in body‐centered‐cubic ferrite matrix. Herein, it is found that Zr addition changes the dynamic precipitation features of Laves phase in FeCrAl alloy during high‐temperature deformation, from only one type of Fe2M (M = Nb, Mo, Ta) Laves phase to Fe2Zr combining Fe2M‐type Laves phase. The Fe2Zr‐type Laves phase precipitates dynamically first, and the interface precipitates between which with ferrite matrix creates more nucleation sites for subsequent precipitation of Fe2M Laves phase. The results can be possibly applied for alloy design and microstructure tailoring in series of FeCrAl alloys used for ATF cladding in the near future.