bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of novel engineered materials from nano‐silica incorporated phenol‐formaldehyde‐flax fabric hybrid composite: Thermal, wear, aging and biodegradability analysis
Authors: Lakshmipriya Ravindran , Unnikrishnan T. G. , Soney C. George , Sreekala M. S. , Sabu Thomas
Published: August 2024

With the growing awareness of environmental issues, natural fiber composites have emerged as a viable substitute for conventional polymer composites. The usage of natural fiber reinforced with nano fillers composites has increased significantly in recent years, especially in the building, automotive, and aerospace industries. This research explores the effect of nano‐silica in tribological, thermal behavior, water diffusion properties and biodegradation of flax fabric/phenol‐formaldehyde hybrid composites. We have fabricated the hybrid composites utilizing compression molding technique. The results showed that after reaching the lowest value for 4 nanosilica (NS), the volumetric wear rose when the addition of nano‐silica was increased. However, the volumetric wear decreased as the weight percentage of nano‐silica improved. At lower sliding speeds (1 m/s), the VW value is between 0.06782 and 0.05455 cm3, but at higher sliding speeds (3 m/s), it is roughly 0.09253–0.06187 cm3. The thermal stability was improved for 1 NS, 2 NS, and 3 NS is 1.20%, 1.64%, and 0.71%, respectively. At three different temperatures (30, 60, and 90°C) the impact of nano‐silica on the water diffusion behavior of PF‐flax fabric hybrid composites was examined. 2 NS showed the least amount of water sorption. it was noted that the three coefficients—Diffusion, Sorption, and Permeation‐were all declining when compared to PF‐flax fabric composites devoid of nano‐silica following computing the Arrhenius values, the free energy change was always negative, indicating the spontaneity of sorption in non‐reinforced samples. The tensile strength of every composite in this investigation was marginally changed by the water aging process.
Characteristics and competitive mechanisms of polycondensation and cyclization induced by end‐groups in polyamide 6 melt
Authors: Chen Kefan , Wang Yongjun , Zhou Liangliang , Dai Junming , Chen Wenxing , Lu Wangyang
Published: August 2024

Polycondensation and ring‐formation reactions are the main factors that cause instability in the molecular structure of commercial polyamide 6 (PA6) during melting. In this study, the mechanisms and interactions of the ring‐formation and polycondensation reactions induced by various factors were thoroughly investigated. The findings suggest that the average molecular weight of PA6 increased by 20.4% during melting. The total monomer and oligomer content increased by 79.2%, and the ring‐forming reaction was promoted with an increase in temperature. Moreover, a high concentration of the end‐amino in PA6 promoted the ring‐forming reaction, whereas similar concentrations of the end‐amino and end‐carboxyl groups were more conducive to the polycondensation reaction. In short, the nitrogen atoms in the end‐amino group on the PA6 molecular chain attack the carbonyl carbon at different sites, including the carbonyl carbon in the amide bond and the carbonyl carbon in the end‐carboxyl group, which is the key to the strength of the ring‐formation and polycondensation reactions.
Discovery of anisiflupurin, an inhibitor of cytokinin dehydrogenase that mitigates heat‐induced yield reduction in rice
Authors: Leipner Jörg , Ruta Nathinee
Published: August 2024

BACKGROUND

In a screening of anilinopurine, anisiflupurin was identified as potent inhibitor of cytokinin dehydrogenase/oxidase (CKX). Inhibitors of CKX have been supposed to be potent plant growth regulators to alleviate the detrimental effects of abiotic stress on crop production. The aim of the study was to profile anisiflupurin in a set of physiological assays and to evaluate its potential for heat stress mitigation in rice field trials.

RESULTS

Anisiflupurin delayed dark‐induced senescence and increased transpiration in detached maize leaves in a dose‐dependent manner. Similarly, the transpiration of young rice plants under heat stress was increased for several days after application with anisiflupurin. Application of anisiflupurin during early phases of generative growth not only restored heat‐induced pollen alterations it increased grain yield in field grown rice under heat conditions as demonstrated in a large field program conducted in southeast Asia. Thereby, efficacy of anisiflupurin was rate‐dependent and most effective when applied during early generative growth phases prior heat stress.

CONCLUSIONS

Application of anisiflupurin secures seed setting by protecting pollen development and enhances grain weight under heat stress conditions in rice. The results of this research opens up a promising avenue for mitigating the adverse effects of heat stress in rice cultivation. © 2024 Society of Chemical Industry.
Discovering new mode‐of‐action pesticide leads inhibiting protein–protein interactions: example targeting plant O‐acetylserine sulfhydrylase
Authors: Ben‐Shushan Rotem Shelly , Cohen Elad , Ben‐Naim Noam , Amram Eytan , Gressel Jonathan , Peleg Dotan , Dotan Nesly , Bloch Itai , Gal Maayan
Published: August 2024

BACKGROUND

The widespread evolution of pesticide resistance poses a significant challenge to current agriculture, necessitating the discovery of molecules with new modes of action. Despite extensive efforts, no major molecules with new modes of action have been commercialized for decades. Most pesticides function by binding to specific pockets on target enzymes, enabling a single target site mutation to confer resistance. An alternative approach is the disruption of protein–protein interactions (PPI), which require complementary mutations on both interacting partners for resistance to occur. Thus, our aim is the discovery and design of small‐molecule inhibitors that target the interface of the PPI complex of O‐acetylserine sulfhydrylase (OASS) and serine acetyltransferase (SAT), key obligatory interacting plant enzymes involved in the biosynthesis of the amino acid cysteine.

RESULTS

By employing in silico filtering techniques on a virtual library of 30 million small molecules, we identified initial hits capable of binding OASS and interfering with its interaction with a peptide derived from SAT with a half‐maximal inhibitory concentration (IC50) of 34 μm. Subsequently, we conducted molecular chemical optimizations, generating an early lead molecule (PJ4) with an IC50 value of 4 μm. PJ4 successfully inhibited the germination of Arabidopsis thaliana seedlings and inhibited clover growth in a pre‐emergence application at an effective concentration of 4.6 kg ha−1.

CONCLUSION

These new compounds described herein can serve as promising leads for further optimization as herbicides with a new mode‐of‐action. This technology can be used for discovering new modes of action chemicals inhibiting all pest groups. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Jellyfish‐inspired multimodular bionic amphibious robot
Authors: Ma Pan , Qu Haibo , Liu Wenju , Wang Xiaolei , Wang Haoqian , Hu Buqin , Guo Sheng
Published: August 2024

To make the amphibious robot have a lot of functions while keeping the overall structure relatively simple, this paper proposes a multimodule bionic amphibious robot (MMBAR) inspired by the movement mode of jellyfish. The MMBAR consists of four modules, which are connected by snaps, and can be assembled quickly. The wing–leg structure suitable for swimming in the water is designed, which combines the legs and wings using a flexible hinge. Meanwhile, the integrated design principle is adopted to combine the wing–leg structure with the wheel structure to design a deformable wheel suitable for land movement. The overall structure of the MMBAR is simple, and the wing–legs can be deformed to perform a variety of functions, such as acting as a wheel for land movement, as a claw for grasping objects, and as a propulsion mechanism to power the MMBAR for swimming. Theoretical modeling and simulation analyses are conducted separately for the MMBAR on land and in water, which helps understand the movement characteristics of the MMBAR and to obtain more optimized movement parameters. In addition, we conducted experiments on the MMBAR, such as climbing slopes, climbing steps, walking on snow, swimming in water, grasping objects, and so forth, which confirm that the MMBAR possesses a strong ability to adapt to the environment. These research results add new content to the research of amphibious robots, which are expected to replace humans to fulfill more dangerous jobs.
Key technology of temporary support robot for rapid excavation of coal mine roadway
Authors: Zhang Heng , Ma Hongwei , Mao Qinghua , Xue Xusheng , Wang Chuanwei
Published: August 2024

The coal industry has long been troubled by the imbalance between mining and tunneling, and between excavating and support. The main cause of this problem is the inability to perform excavating and permanent support operations in parallel. Additionally, the limited space near the tunneling face hampers the efficiency of permanent support. Temporary support is an effective method to ensure the stability of the surrounding rock and expand the space for parallel operations between excavating and permanent support activities. This work provides a brief overview of the current research status on temporary support, emphasizing that the key to achieving safe, efficient, and rapid excavation lies in the development of temporary support robots. To meet the development needs of temporary support robots, three key technologies are proposed: the construction of a coupling model between the robot and the surrounding rock, spatial layout optimization of the rapid advancement system, and adaptive control of the robot. This work details the methods and approaches for constructing the coupling model, the elements of system spatial layout optimization, and the methods and strategies for the robot's adaptive control. Our team successfully tested the shield robot system at Xiaobaodang Mining Company, verifying the feasibility of these key technologies.
How effective are trade policy and monetary policy in achieving a pathway to sustainable development? Evidence from a wavelet quantile‐on‐quantile Granger causality analysis
Authors: Adebayo Tomiwa Sunday , Olanrewaju Victoria Olushola
Published: August 2024

The paper explores the impact of trade policy (TRP) and monetary policy (MP) on CO2 emissions in the United States over the period February 1, 1988–December 12, 2022. The study employed wavelet quantile‐on‐quantile regression (WQQR) to explore the relationship across different quantiles and time‐scales. Furthermore, the present study introduced wavelet quantile‐on‐quantile Granger causality (WQQGC) to explore the predictive power of the independent variable over the dependent variable with a focus on different time‐scales and quantiles. The use of wavelet quantile‐based tools is supported by the nonlinear and non‐normal distribution of the variables. The results from WQQR show that in the short and medium term, an increase in renewable energy consumption (REC) in the United States is accompanied by an increase in CO2 emissions. However, in the long term, across all quantiles, REC effectively reduces CO2. In the short and medium term, the negative impact of TRP on CO2 emissions is apparent; however, we observed a supportive positive effect of TRP on reducing CO2 emissions in the long term. Across all periods, the influence of MP on CO2 emissions is generally weak yet positive; however, there are instances of negative associations. Across all quantiles in the short term, the impact of natural gas on CO2 emissions remains positive, although this positive effect diminishes in the long term. Finally, all the regressors can significantly predict CO2 emissions at dissimilar quantiles and time‐scales. The study formulates Sustainable Development Goals policies based on the above findings.
Eccrine Angiomatous Hamartoma Treated with Multimodal Vascular Laser and Incobotulinum
Authors: Gu Yaron , Truong Kelvin , Kossard Steven , Lim Adrian , Sebaratnam Deshan F.
Published: August 2024

Eccrine angiomatous hamartoma (EAH) is a rare benign vascular lesion that is distinguished histologically by vascular and eccrine overgrowth. We report the case of a 46-year-old woman with EAH who was successfully treated with multimodal incobotulinum toxin A, pulsed dye laser and long-pulsed neodymium-doped yttrium aluminium garnet laser.
KOtBu Assisted Regio‐ and Stereo‐Selective Alkoxy‐Isomerization of Ortho‐Alkynyl Allylic Alcohols: Synthesis of Alkylidene Dihydroisobenzofurans and Indenones
Authors: Biswas Dwaipayan , Kishore Dakoju Ravi , Naveen Jakkula , Satyanarayana Gedu
Published: August 2024

A transition metal‐free synthesis of alkylidene dihydroisobenzofurans from the ortho‐alkynyl allylic alcohols is reported herein. Notably, a simple base tBuOK is utilized for the 5‐exo‐dig cyclization and double bond isomerization of ortho‐alkynyl allylic alcohols to furnish alkylidene dihydrobenzofurans with Z‐stereoselectivity under shorter reaction times. In addition, the geometry of the double bonds was confirmed by 1D Selective Gradient NOESY and 2D NMR (NOESY) analysis. Furthermore, the effectuality of the ortho‐alkynyl allylic alcohols has been shown by extending to the one‐pot synthesis of indanones via aqueous acid‐mediated hydrolysis (ring‐opening) of in‐situ formed dihydroisobenzofurans followed by intramolecular condensation reaction under acidic conditions
Fabrication of Ag2MoO4/CuWO4 Nanocomposite Photocatalyst for the Degradation of Rhodamine‐B
Authors: Jatav Neha , Kumar Uttam , Shrivastava Anshu , Singh Nivedita , Sinha Indrajit
Published: August 2024

Herein, we investigate the photocatalytic properties of a new Ag2MoO4/CuWO4 composite. Three different composites with 5, 10, and 15 weight percent of fine Ag2MoO4 nanostructures were precipitated on CuWO4 nanoparticles. Given the staggered valence and conduction band positions of the two components, the composite with the 10 % weight percent Ag2MoO4 loading on CuWO4 demonstrated the slowest recombination kinetics. The same composite also exhibited the best photocatalytic degradation of RhB under UV light irradiation. The photocatalytic turnover frequency of this composite was also among the best reported for RhB degradation reported in the literature. Photocatalytic kinetics, active species trapping, and various control experiments were carried out to get an insight into the photocatalytic mechanism. The optimum photocatalyst exhibited its highest activity at pH 3 and a RhB degradation turnover frequency (photocatalytic activity) comparable to the best values reported in the literature.
Greener Synthesis of Copper Oxide Nano‐Particles Using Rivina Humilis L. Plant Extract, Characterization and Their Biological Evaluation for Anti‐Microbial and Anti‐Oxidant Activity
Authors: Sheikh Sartaj , Mungole Arvind J. , Pandhurnekar Chandrashekhar P. , Kanfade Harsha P. , Pandhurnekar Himani C. , Pawar Abhimanyu P.
Published: August 2024

Synthesis of nano‐particles using various greener approaches such as the use of plant extract, microbes, etc. is gaining a lot of popularity in the scientific community due to their advantages of being a cheaper protocol, reduction in the use of less hazardous chemicals, more environmentally benign method and good yield. It has been previously reported by many research groups that plant material provides reducing, capping as well as stabilizing agents and brings down biological and environmental risks in the green synthesis of nano‐particles. So it was thought worthwhile to synthesize copper oxide nano‐particles (CuO NPs) using some locally available medicinal plants. Rivina humilis L. plants which are available in our region of Vidarbha in Maharashtra State, India are considered to be the herbal plant for the treatment of respiratory‐related disorders mainly for asthma and cold by local tribal peoples. It has been found that it contains a variety of phytochemicals which can be employed for the synthesis of nanomaterials. With this aim it was thought worthwhile to present an efficient and greener approach for the synthesis of copper oxide nano‐particles using Rivina humilis L. (RH) whole plant extract. For characterization of bio‐synthesized CuO NPs, various spectral and analytical techniques such as UV‐Vis spectroscopy, FT‐IR, XRD, SEM, TEM, and EDS were employed. The newly synthesized CuO NPs were also tested for their potential biological activities against six different bacterial stains namely E. coli, P. aeruginosa, S. aureus, P. vulgaris, B. subtilis, and S. typhi using the well diffusion method. The antioxidant efficacy of the synthesized CuO NPs was undertaken through 1,1‐Diphenyl‐2‐picrylhydrazyl (DPPH) free radical scavenging activity. Their results have been presented and discussed in the present work.
Fabrication of an In‐situ Synthesized Porous Silica‐Ruthenium‐Nickel Composite Catalyst for Hydrolysis of Ammonia Borane
Authors: Umegaki Tetsuo , Uchida Takanobu , Imai Haruhiro , Xu Qiang , Kojima Yoshiyuki
Published: August 2024

This work investigated in‐situ synthesis of porous silica‐nickel‐ruthenium composite catalysts for hydrolysis of ammonia borane. The precursors were prepared with an anionic surfactant, sodium dodecyl sulfate (SDS), to form porous structure in the precursor particles, and the precursors was treated in aqueous solution including sodium borohydride and ammonia borane for in‐situ process to parallelly activate and use the catalysts for hydrolysis of ammonia borane. The result of TEM and nitrogen sorption measurements suggested that the primary particle size of the in‐situ synthesized catalysts decrease with increasing the amount of SDS and sodium chloride as the additive for controlling the primary particle size probably because of the effect of sodium ions to inhibit nuclei growth of the primary particles. From the EDS analyses, the composition of active nickel and ruthenium contents increased with increasing the amount of SDS and sodium chloride except for the highest amount of SDS probably because of adsorption of the metal cations with the excess amount of the surfactant anion to decrease the amount of the metal cations including the catalyst. The in‐situ synthesized catalyst including small size primary particles and high nickel and ruthenium content tended to exhibit high activity for hydrolysis of ammonia borane.
Metal‐Ion and UVC Light‐Catalyzed Oxidation and Biodetoxification of Ponceau Xylidine in Aqueous Solution: A Comparative Study
Authors: Marbaniang Morten , Kumar John Elisa , Mulai Tsungom , Kharmawphlang Wanshanlang , Sharan Rajeswar N. , Sahoo Mihir Kumar
Published: August 2024

Metal ion (
/oxidant) and UV light catalyzed (UV/oxidant) mineralization and biodetoxification of Ponceau Xylidine (PX) was undertaken in this study. Hydrogen peroxide (HP) and ammonium persulphate (APS) were employed as oxidants and
and
as metal ion catalysts. Although highest mineralization in
/APS and UV/HP systems was exhibited at pH 1 (63.09 %) and 3 (64.83 %), respectively, lowest was shown by
/oxidant systems at any pH. The Fenton process achieved mineralization of ≈48.50 % within the pH range of 3 to 6.15. The study established
as a better catalyst than
, and HP, a better oxidant (2.5 times more effective) than APS. Mineralization with UV/HP at 120 min is highest at pH 3 (92.0 %) and 6.15 (86.17 %). Various inorganic anions were found to inhibit mineralization. The maximum and minimum inhibition was shown by
in UV/HP and UV/APS systems respectively. The inhibition effect of
decreases with concentration till 0.01 mM, beyond which an increasing trend was observed. This study also demonstrates that the biodetoxification efficiency of various systems is in the order: UV/HP>UV/APS>
/HP. Thus, UV/HP is the most suitable system for the treatment of PX, displaying a biodetoxification efficiency of 83.0 % and mineralization of 92.0 %.
Crystallization Kinetics and Melting Behavior of Novel Biobased Poly(butylene 2,5‐thiophenedicarboxylate)
Authors: Chen Changlin , Pan Siyu , Qiu Zhaobin
Published: August 2024

Poly(butylene 2,5‐thiophenedicarboxylate) (PBTh) is a novel biobased semicrystalline polyester with superior thermal, mechanical, and gas barrier properties; however, the crystallization kinetics and melting behavior of PBTh have not been studied in detail so far. The crystallization kinetics of PBTh was first studied in this research. The Ozawa equation failed to describe the nonisothermal melt crystallization kinetics of PBTh due to the secondary crystallization. The crystallization activation energy value was calculated by the Friedman method, which was negative and exhibited the conversion dependence. The isothermal melt crystallization kinetics of PBTh was well described by the Avrami equation in a wide range of crystallization temperature from 84 to 120 °C. PBTh showed the fastest crystallization rate at 104 °C; moreover, the Avrami exponent value slightly varied between 2.2 and 2.7, suggesting the same crystallization mechanism within the investigated temperature range. PBTh displayed one or two melting endotherms depending on crystallization temperature, which was well explained by the melting, recrystallization, and remelting mechanism. In addition, the equilibrium melting point of PBTh was estimated to be 163.1 °C with the Hoffmann−Weeks equation.
Acid Mediated In‐Situ Catalytic Cleavage/Making of C=N Bonds in Bis‐Hydrazone Uranyl Complexes: Exploration of Photophysical, Electrochemical, Dye Sorption Properties and DFT Studies
Authors: Devi Sarau , Nayak Sampurna , Richard Bartholomew , Ravindran Reena , Salaria Punam , Chatterjee Aditi , Arivazhagan C. , Garai. Abhijit , Reddy M Amarendar , Kim Sung Yeol , Konavarapu Satyanarayana K.
Published: August 2024

Two new uranium complexes [UO2L2(H2O)] (where L2=diacetyl bis‐isonicotinoyl hydrazone) complex 1, and [UO2(L1)2] (where L1=diacetylmonoxime isonicotinoylhydrazone) complex 2, have been synthesized by precisely adjusting the pH values of the reaction system. Complex 1 was formed in an acidic ethanolic solution (pH=3) through an in‐situ acid catalytic reaction of diacetylmonoxime isonicotinoylhydrazone and UO2(NO3)2.6H2O, while complex 2 was acquired in a neutral medium (pH=7) through self‐assembly of two ligands and one uranium (VI) metal centre. Both complexes were thoroughly characterized by elemental analysis, UV‐Visible spectroscopy, IR spectroscopy, NMR, TGA, cyclic voltammetry, and powder X‐ray diffraction. The studies indicate that the bis‐hydrazone in complex 1 is a dianionic tetradentate N2O2 donor, whereas in complex 2 it is a monoanionic tridendate N2O donor. The formation of complex 1 was further confirmed by a single‐crystal X‐ray diffraction study, which revealed the role of a water molecule in forming a pentagonal bipyramidal geometry of [UO2L2(H2O)]. Photophysical studies revealed that complexes 1 and 2 exhibited low band gap values of 2.07 and 2.12 eV, respectively, indicating their semiconducting nature. From the CV measurements, the higher negative potentials of the complexes 1 & 2 {1, −0.6 V and 2, −0.5 V vs. ferrocenium/ferrocene (Fc+/Fc)} in DMSO are assigned to the presence of {UO2}2+/{UO2}+ couple signifying their redox active nature. Dye adsorption studies show that both the complexes were able to remove 90 % of Methylene blue (MB) and Rhodamine B (RhB) from the solutions with the concentration of 10−5 M. The structural insights and electronic properties of Ligand HL1 and complex 1 were further explored by density functional theory (DFT) calculations.
Isoniazid Derivatives as Potential Lipoxygenase‐15 Inhibitors: In‐vitro and In‐silico Studies
Authors: Alghamdi Mashael A. , Azam Faizul , Jamir Anwar Md , Mahmood Danish , Ali Mohamed A. M. , Khan Majid
Published: August 2024

The enzymatic oxidation of polyunsaturated fatty acids, particularly arachidonic acid, produces important lipid mediators such as leukotrienes and prostaglandins, which are critical for triggering inflammatory cascades in the body. The enzyme lipoxygenase‐15 (LOX‐15) plays a crucial role in the oxygenation of unsaturated fatty acids. Targeting this enzyme for inhibition is essential for diminishing inflammation and averting numerous potentially fatal diseases. Therefore, the inhibitory activity of a series of isoniazid derivatives, selected from our in‐house library, was assessed against LOX‐15 by employing both in vitro and in silico methods. Among the 23 compounds evaluated, 15 showed activity in vitro. Notably, compound 7 was the most effective, demonstrating an IC50 value of 1.4±0.1 μM while the standard inhibitor, NDGA, showed an inhibition at 9.4±0.6 μM. These compounds were found to competitively inhibit LOX‐15, with Ki values ranging from 1.2–7.1 μM. Molecular docking was utilized to investigate the intermolecular interactions among the active compounds. The thermodynamic stability of the compound 7 and NDGA in complex with LOX‐15 was verified through 100 ns of molecular dynamics simulations. Post‐simulation analyses involved RMSD, RMSF, RoG, free energy landscape, principal component analysis, and dynamic cross‐correlation matrix. Compound 7 and NDGA had MM/GBSA binding energies of −54.14±2.55 kcal/mol and −35.24±3.23 kcal/mol, respectively. The study underscores the significant potential of isoniazid derivatives in LOX‐15 inhibition and their role in managing inflammatory diseases.
Deciphering the Impact of Cyclization and Lysine Charges on Antimicrobial Peptides Using Molecular Dynamics Simulations and Density Functional Theory
Authors: Saghiri Afsane , Reza Bozorgmehr Mohammad , Morsali Ali
Published: August 2024

This study utilized molecular dynamics simulations (MD) to explore the impact of cyclization and lysine charges on antimicrobial peptides (AMPs) across eight simulation boxes designed with water and water‐sodium dodecyl sulfate (SDS) micelles. Cyclic AMPs with positively charged lysine residues (c‐AMP+) displayed increased stability in both environments compared to linear AMPs (l‐AMP+), with removal of positive charges notably destabilizing the linear form in water‐SDS. Findings revealed enhanced mobility due to cyclization and charged lysine residues, further boosted by SDS presence. Notably, lysine residues exhibited a stronger affinity for SDS than tryptophan and phenylalanine, especially lysine number 5. Analysis extended to peptide backbone conformation and electronic features, showing cyclization's greater impact on psi and phi angles over charge presence, with linear AMPs displaying lower reactivity than cyclic counterparts. This research underscores the significance of cyclization and lysine charges in AMP behavior, suggesting the potential of c‐AMP+ for further development owing to their improved stability, mobility, and membrane interactions.
2‐DPC Mediated Effective Synthesis of Peptide Conjugates, their Antifungal and Antibacterial Properties
Authors: Kumari Dalli , Vhanmane Vaishnavi Raosaheb , Gouthami Kuruvalli , Reddy Vaddi Damodara , Nagendra Govindappa
Published: August 2024

The present work demonstrates the effective synthesis of amide derivatives of Nα‐protected amino acids and aryl/heteroaryl amines using di‐2‐pyridyl carbonate (2‐DPC) and cat. DMAP mediated coupling reaction. Several coupling methods were employed for the screening of the amides using EDC, HATU, mixed anhydride, T3P, CDI, COMU, DPTC, and 2‐DPC, where 2‐DPC/cat. DMAP method furnished amides with better yields and purity in shorter durations. Seventeen amide derivatives (3 a–3 q) were successfully synthesized using the present protocol and were characterized by NMR, mass and IR spectroscopy. Further, we performed the in‐silico and in‐vitro studies on the synthesized molecules on antifungal and antibacterial activity. Molecular docking studies reveal the binding affinity of protein‐ligand interactions ranging from −6.2 to −11.0 kcal/mol (Aspergillus Niger Esta), −5.9 to −9.9 kcal/mol (DNA gyrase subunit B) and −6.4 to −13.4 kcal/mol (CYP51B). Compounds like 3 d, 3 e, 3 h, 3 i, 3 j and 3 l exhibit the highest antibacterial and antifungal activity when compared to the standards delafloxacin, ketoconazole, and bifonazole in in‐silico studies. Whereas the in‐vitro studies also unveiled good antimicrobial activity with peptide conjugates. The results of antimicrobial activity exhibits in antifungal species show the good activity concentrations in compounds 3 j is 11.2±3.54 μg/mL and 3 l is 10.3±2.76 μg/mL. The anti‐bacterial species exhibit the compound 3 g showing good activity in different concentrations 12±3.08 μg/mL, 12.2±3.04 μg/mL, 12.6±2.78 μg/mL and 12.5±2.98 μg/mL.
Peptide Based Quantum Dots Conjugates as Promising Theranostic Candidates in Nanomedicines: Applications in Drug Delivery and Bioimaging
Authors: Saima  , Aggarwal Varun , Bala Ekta , Kachore Ankit , Singh Hemant , Kushwaha Sapana , Kumar Rakesh , Kumar Verma Praveen
Published: August 2024

Advancement in nanotechnology paves new way in nanomedicine via synthesis of various scaffolds bearing multifunctionalities having characteristics of both as diagnostic and therapeutic applications. Quantum dots (QDs) with exceptional luminescent properties exhibited some unbeatable characteristics of small size with ease in surface modifications and thus make them suitable candidates to be used in drug delivery and diagnosis of diseases. Meanwhile, various type of peptides are known in literature for their excellent therapeutic properties and thus make them promising candidates to be used as conjugate partner with the QDs. Highly luminescent properties and surface modifications flexibility of QDs, further urge to use them as promising conjugate partner with many small molecules including peptides and thus found applications in the field of nanomedicines. Thus Peptides ‐QDs conjugates exhibited the properties of both QDs and bioactivity, biocompatibility features of peptides and hence leave behind the limitation of both the individual partners (i. e. QDs and peptides). Thus the combined Peptides‐QDs conjugates acts as theranostic agent for various diseases where these acts as both imaging and drug delivery agent. Hence the present review focused on the theranostic applications of the Peptides‐QDs conjugates in various area of the nanomedicines. Also we focus on the area of improvement and advancement in nanomedicines for the diagnosis and treatment of the diseases in the early stages.
New Pathway for the Synthesis of Pyrimido[4,5‐b]quinolines via One‐pot Reaction of Isatins, 6‐Aminouracils and 1,3‐Dimethylbarbituric Acid
Authors: Arizavi Marziyeh , Reza Mohammadizadeh Mohammad , Saberi Dariush , Ghodrati Atefeh , Fatemeh Hashemi S.
Published: August 2024

The reaction between 6‐aminouracils and isatins having no substitution on nitrogen was carried out in acetic acid at 80 °C. This was followed by the oxidative decarboxylation of the resulting intermediates in the presence of Pb(OAc)4, resulting in the synthesis of the corresponding 6‐aminouracil substituted pyrimido[4,5‐b]quinolines with good to excellent yields. Additionally, the reaction of 6‐aminouracils, isatin derivatives, and 1,3‐dimethylbarbituric acid yielded similar results, and the corresponding products were efficiently obtained with symmetric and asymmetric structures. Furthermore, N‐substituted isatins were also subjected to the reaction conditions and the resulted spirooxindoles prepared, showing resistance against oxidation with (Pb(OAc)4. Notably, the condensation reaction of N‐substituted isatins with N‐arylaminouracils was also investigated, leading to spiro[indoline‐3,5′‐pyrimido[4,5‐b]quinoline] derivatives.
Antitumor Activity of New Pd(II) Complexes with Ligands Derived from O‐Vanillin Acting as Topoisomerase I and II Inhibitors
Authors: Franco Mariane A. , Guedes Adriana P. M. , Batista Alzir A. , Deflon Victor M. , Akinyemi Amos O. , Rocha Josias S. , Rocha Fillipe V.
Published: August 2024

This study investigates topoisomerase I and II enzyme inhibition by novel Pd(II) complexes. TSC represents the chelating ligand thiosemicarbazone, which is modified at its 4(N)‐nitrogen terminal position with substituents such as C2H5, CH3, and H. PR3 represents the triphenylphosphine ligand, with positional variations including para substituents H, F, OCH3, and CH3. The aim is to establish a correlation between these molecular variations and cytotoxicity. In particular, the compounds show promising cytotoxicity against MDA‐MB‐231 and A549 tumor cell lines, especially those with H substitution at the terminal position 4(N) of TSC and H and F in the triphenylphosphine. The results suggest that a smaller molecular volume of ligand substituents may enhance the cytotoxic effects. The inhibitory potential of the complexes against DNA topoisomerase enzymes was investigated. The IC₅₀ values of the most promising complexes strongly inhibit TOPOIIα and TOPOIβ, suggesting these enzymes as primary targets. These complexes exhibited significantly lower IC₅₀ values (4.32–4.88 μM) compared to cisplatin (10.2 μM) against MDA‐MB‐231 cells, indicating a distinct mode of action. However, it is noteworthy that the complexes did not inhibit the action of DNA topoisomerase IIβ, suggesting selectivity against specific isoforms of DNA topoisomerase II that act as catalytic inhibitors.
Comparing the MP2, DKH2‐MP2 and SCAN Hybrid Forces Molecular Dynamics Simulation on the Structure and Dynamics of Hydrated Ion Ba2+ in Aqueous Solution
Authors: Prasetyo Niko , Anjani Seruni Gita , Kusuma Alberto Krishna Ksatria Winning , Iqbal La Ode Muhamad
Published: August 2024

The study investigated the structural and dynamical properties of hydrated ion Barium (Ba2+) in aqueous solution using quantum mechanical/molecular mechanical molecular dynamics simulations (QM/MM MD simulation). The primary objective was to assess the performance of the SCAN functional in describing the structure and dynamics of formed Ba2+ hydration shells in aqueous solution. The SCAN/MM MD simulation demonstrated the closest agreement with previously reported experimental data regarding the structural and dynamical properties of hydrated ion Ba2+. Specifically, the Ba2+ and surrounding water molecules distance was determined to be 2.79 Å, with equal distribution of coordination numbers of 8 and 9 in the first hydration shell. Moreover, the stretching frequency of 232.21 cm−1 closely matched the CCSD(T) results. The obtained results from SCAN/MM MD has a better agreement than results from MP2/MM and DKH2 MP2/MM molecular dynamics simulation. These findings underscore the potential of SCAN/MM MD simulation as a promising method for investigating the structural and dynamical properties of hydrated ions.
Purpose in life and stress: Momentary associations from a micro‐longitudinal study
Authors: Sutin Angelina R. , Luchetti Martina , Stephan Yannick , Stokes Jeffrey E. , Terracciano Antonio
Published: August 2024

Purpose in life is an aspect of well‐being associated with less subjective stress. The present research sought to expand this literature by testing the association between both dispositional and momentary purpose with stress in daily life using a micro‐longitudinal study design. Participants (N = 303) reported their dispositional purpose at baseline and reported their momentary purpose and stress three times a day for 8 days. Between‐person, dispositional purpose was associated with less momentary stress across the 8 days tested with linear regression (β = −0.29, 95% CI = −0.39, −18, p < 0.001); it was unrelated to variability in stress (β = 0.05, 95% CI = −0.05, 0.14, p = 0.310). In contrast, the within‐person analysis tested with multilevel modelling indicated that in moments when participants felt more purpose‐driven than their average, they felt more stressed (b = 0.09, 95% CI = 0.06, 0.12, SE = 0.01, p < 0.001). This association was slightly stronger among participants with relatively lower dispositional purpose (binteraction = −0.04, SE = 0.02, 95% CI = −0.08, −0.01, p = 0.032). This study replicated the negative association between dispositional purpose and subjective stress when stress was measured at moments in daily life. It also found that feeling more purpose‐driven than usual in the moment is stressful, a counterintuitive finding that, if replicated, suggests that striving for purpose can be stressful in the moment, even if feeling more purposeful in general is associated with lower stress.
Redox‐Responsive AIEgen Diselenide‐Covalent Organic Framework Composites Targeting Hepatic Macrophages for Treatment of Drug‐induced Liver Injury
Authors: Zhuang Jialu , Zhang Hao , Wu Jin , Hu Danyou , Meng Tao , Xue Jing , Xu Hanyang , Wang Gang , Wang Hua , Zhang Guiyang
Published: August 2024

The escalating misuse of antipyretic and analgesic drugs, alongside the rising incidents of acute drug‐induced liver injury, underscores the need for a precisely targeted drug delivery system. Herein, two isoreticular covalent organic frameworks (Se‐COF and Se‐BCOF) are developed by Schiff‐base condensation of emissive tetraphenylethylene and diselenide‐bridged monomers. Leveraging the specific affinity of macrophages for mannose, the first precise targeting of these COFs to liver macrophages is achieved. The correlation is also explored between the therapeutic effects of COFs and the NLRP3/ASC/Caspase‐1 signaling pathway. Utilizing this innovative delivery vehicle, the synergistic delivery of matrine and berberine are accomplished, compounds extracted from traditional Chinese medicine. This approach not only demonstrated the synergistic effects of the drugs but also mitigated their toxicity. Notably, berberine, through phosphorylation of JNK and up‐regulation of nuclear Nrf‐2 and its downstream gene Mn‐SOD expression, simultaneously countered excessive ROS and suppressed the activation of the NLRP3/ASC/Caspase‐1 signaling pathway in injured liver tissues. This multifaceted approach proved highly effective in safeguarding against acute drug‐induced liver injury, ultimately restoring liver health to normalcy. These findings present a novel and promising strategy for the treatment of acute drug‐induced liver injury.
Direct Exfoliation of Nanoribbons from Bulk van der Waals Crystals
Authors: Saunders Ashley P. , Chen Victoria , Wang Jierong , Li Qitong , Johnson Amalya C. , McKeown‐Green Amy S. , Zeng Helen J. , Mac T. Kien , Trinh M. Tuan , Heinz Tony F. , Pop Eric , Liu Fang
Published: August 2024

Confinement of monolayers into quasi‐1D atomically thin nanoribbons could lead to novel quantum phenomena beyond those achieved in their bulk and monolayer counterparts. However, current experimental availability of nanoribbon species beyond graphene is limited to bottom‐up synthesis or lithographic patterning. In this study, a versatile and direct approach is introduced to exfoliate bulk van der Waals crystals as nanoribbons. Akin to the Scotch tape exfoliation method for producing monolayers, this technique provides convenient access to a wide range of nanoribbons derived from their corresponding bulk crystals, including MoS2, WS2, MoSe2, WSe2, MoTe2, WTe2, ReS2, and hBN. The nanoribbons are predominantly monolayer, single‐crystalline, parallel‐aligned, flat, and exhibit high aspect ratios. The role of confinement, strain, and edge configuration of these nanoribbons is observed in their electrical, magnetic, and optical properties. This versatile exfoliation technique provides a universal route for producing a variety of nanoribbon materials and supports the study of their fundamental properties and potential applications.
An Integrated Nanoplatform via Dual Channel Excitation for Both Precise Fluorescence Imaging and Photodynamic Therapy of Orthotopic Breast Tumor in NIR‐II Region
Authors: Lv Kehong , Wang Hongli , Fu Xinyu , Chen Shengzhe , Zhang Ruohao , Zhou Yifei , Feng Jing , Zhang Hongjie
Published: August 2024

Although research on photodynamic therapy (PDT) of malignant tumor has made considerable progress in recent years, it is a remaining challenge to extend PDT to the second near‐infrared window (NIR‐II) along with real‐time and accurate NIR‐II fluorescence imaging to determine drug enrichment status and achieve high treatment efficacy. In this work, lanthanide nanoparticles (Ln NPs)‐based nanoplatform (LCR) equipped with photosensitizer Chlorin e6 (Ce6) and targeting molecular NH2‐PEG1000‐cRGDfK are developed, which can achieve NIR‐II photodynamic therapy (PDT) and NIR‐II fluorescence imaging by dual channel excitation. Under 808 nm excitation, Nd3+ in the outer layer can absorb the energy and transfer inward to emit strong NIR‐II emissions (1064 and 1525 nm). Due to the low background noise of NIR‐II light and the targeting effect of NH2‐PEG1000‐cRGDfK, LCR can recognize tiny tumor tissue (≈3 mm) and monitor drug distribution in vivo. Under 1530 nm excitation, internal Er3+ can be self‐sensitized, generating intense upconversion emission (662 nm) that can effectively activate Ce6 for in vivo PDT due to the deep tissue penetration of NIR‐II light. This study provides a paradigm of theranostic nanoplatform for both real‐time fluorescence imaging and PDT of orthotopic breast tumor in NIR‐II window.
Centimeter‐Scale Assembly of Fractal Organic Crystals with Crisscross Structures for Flexible Photosynapses
Authors: Liu Bin , Dong Xuemei , Li Yinxiang , He Zixi , Sun Hongchao , Wang Kaili , Wang Min , Xu Min , Miao Chunyang , Huang Wei , Liu Juqing
Published: August 2024

Fractal assembly technology enables scalable construction of organic crystal patterns for emerging nanoelectronics and optoelectronics. Here, a polymer‐templating assembly strategy is presented for centimeter‐scale patterned growth of fractal organic crystals (FOCs). These structures are formed by drop‐coating perylene solution directly onto a gelatin‐modified surface, resulting in the formation of crisscross fractal patterns. By adjusting the tilt angle of the template, the morphology of FOCs can be effectively controlled, with the diameter distribution of each level branch ranging from hundreds to ten micrometers. The planar FOC device exhibits flexible photoreception and photosynaptic capabilities, with a high specific detectivity of 1.35 × 109 Jones and paired‐pulse facilitation (PPF) index of 104%, withstanding a 0.5 cm bending radius during bending test. These findings present a reliable route for large‐scale assembly of flexible organic crystalline materials toward neuromorphic electronics.
In Situ Formation of Iodide Precursor for Perovskite Quantum Dots with Application in Efficient Solar Cells
Authors: Ye Lvhao , Chen Jingxuan , Zhang Mingxu , Wang Guoliang , Zhang Xiaoliang
Published: August 2024

Perovskite quantum dots (PQDs) become a kind of competitive material for fabricating high‐performance solar cells due to their solution processability and outstanding optoelectronic properties. However, the current synthesis method of PQDs is mostly based on the binary‐precursor method, which results in a large deviation of the I/Pb input ratio in the reaction system from the stoichiometric ratio of PQDs. Herein, a ternary‐precursor method with an iodide source self‐filling ability is reported for the synthesis of the CsPbI3 PQDs with high optoelectronic properties. Systematically experimental characterizations and theoretical calculations are conducted to fundamentally understand the effects of the I/Pb input molar ratio on the crystallographic and optoelectronic properties of PQDs. The results reveal that increasing the I/Pb input molar ratio can obtain ideal cubic structure PQDs with iodine‐rich surfaces, which can significantly reduce the surface defects of PQDs and realize high orientation of PQD solids, facilitating charge carrier transport in the PQD solids with diminished nonradiative recombination. Consequently, the PQD solar cells exhibit an impressive efficiency of 15.16%, which is largely improved compared with that of 12.83% for the control solar cell. This work provides a feasible strategy for synthesizing high‐quality PQDs for high‐performance optoelectronic devices.
An Efficient MnO2 Photocathode with an Excellent SnO2 Electron Transport Layer for Photo‐Accelerated Zinc Ion Batteries
Authors: Gao Xinyu , Tian Dongyue , Shi Zhengguang , Zhang Nana , Sun Ruyu , Liu Jiaming , Tsai Hsu‐Sheng , Xiang Xingde , Feng Wei
Published: August 2024

Photo‐accelerated rechargeable batteries play a crucial role in fully utilizing solar energy, but it is still a challenge to fabricate dual‐functional photoelectrodes with simultaneous high solar energy harvesting and storage. This work reports an innovative photo‐accelerated zinc‐ion battery (PAZIB) featuring a photocathode with a SnO2@MnO2 heterojunction. The design ingeniously combines the excellent electronic conductivity of SnO2 with the high energy storage and light absorption capacities of MnO2. The capacity of the SnO2@MnO2‐based PAZIB is ≈598 mAh g−1 with a high photo‐conversion efficiency of 1.2% under illumination at 0.1 A g−1, which is superior to that of most reported MnO2‐based ZIB. The boosting performance is attributed to the synergistic effect of enhanced photogenerated carrier separation efficiency, improved conductivity, and promoted charge transfer by the SnO2@MnO2 heterojunction, which is confirmed by systematic experiments and theoretical simulations. This work provides valuable insights into the development of dual‐function photocathodes for effective solar energy utilization.
Elasticity Mapping of Colloidal Glasses Reveals the Interplay between Mesoscopic Order and Granular Mechanics
Authors: Vasileiadis Thomas , Schöttle Marius , Theis Maximilian , Retsch Markus , Fytas George , Graczykowski Bartlomiej
Published: August 2024

Colloidal glasses (CGs) made of polymer (polymethylmethacrylate) nanoparticles are promising metamaterials for light and sound manipulation, but fabrication imperfections and fragility can limit their functionality and applications. Here, the vibrational mechanical modes of nanoparticles are probed to evaluate the nanomechanical and morphological properties of various CGs architectures. Utilizing the scanning micro‐Brillouin light scattering (µ‐BLS), the effective elastic constants and nanoparticles' sizes is determined as a function of position in a remote and non‐destructive manner. This method is applied to CG mesostructures with different spatial distributions of their particle size and degree of order. These include CGs with single‐sized systems, binary mixtures, bilayer structures, continuous gradient structures, and gradient mixtures. The microenvironments govern the local mechanical properties and highlight how the granular mesostructure can be used to develop durable functional polymer colloids. A size effect is revealed on the effective elastic constant, with the smallest particles and ordered assemblies forming robust structures, and classify the various types of mesoscale order in terms of their mechanical stiffness. The work establishes scanning µ‐BLS as a tool for mapping elasticity, particle size, and local structure in complex nanostructures.
Microneedle Optimization: Toward Enhancing Microneedle's Functionality and Breaking the Traditions
Authors: Lori Zoudani Elham , Nguyen Nam‐Trung , Kashaninejad Navid
Published: August 2024

Microneedles hold remarkable potential for providing convenient and unique solutions for disease diagnosis and therapy. However, their integration into clinical practices has been slow, primarily due to the challenge of developing models that meet the criteria of a particular application. A comprehensive and systematic analysis of all aspects of microneedle platforms is imperative to overcome this bottleneck. The analysis involves gathering performance‐related information and understanding the factors affecting the functionality of microneedles. The performance of microneedles is heavily influenced by parameters such as dimensions, needle shape, array arrangement, and materials (flexible, stretchable, stimuli‐responsive, biodegradable). This article presents a fresh perspective on microneedles, introducing concepts toward optimal designs across various microneedle platforms. This includes application, design, fabrication techniques, and understanding how a specific microneedle design can effectively meet the requirements of a particular application. By addressing these crucial issues, further advancement of microneedle technology occurs.