bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studying Cation Exchange in {Cr7Co} Pseudorotaxanes: Preparatory Studies for Making Hybrid Molecular Machines
Authors: Bennett Tom S. , Geue Niklas , Timco Grigore A. , Whitehead George F. S. , Vitorica‐Yrezabal Inigo J. , Barran Perdita E. , McInnes Eric J. L. , Winpenny Richard E. P. 
Published: April 2024

AbstractIn the design of dynamic supramolecular systems used in molecular machines, it is important to understand the binding preferences between the macrocycle and stations along the thread. Here, we apply 1H NMR spectroscopy to investigate the relative stabilities of a series of linear alkylammonium templated pseudorotaxanes with the general formula [H2NRR’][Cr7CoF8(O2CCH2tBu)16] by exchanging the cation in solution. Our results show that the pseudorotaxanes are able to exchange threads via a dissociative mechanism. The position of equilibrium is dependent upon the ammonium cation and solvent used. Short chain primary ammonium cations are shown to be far less favourable macrocycle stations than secondary ammonium cations. Collision‐induced dissociation mass spectrometry (CID‐MS) has been used to look at disassembly of the pseudorotaxanes in a solvent‐free environment and stability trends compared to those in acetone‐d6. The energy needed to induce 50 % of the precursor ion loss (E50) is used and shows a similar trend to the equilibria measured by NMR. The relative stabilities of these hybrid inorganic‐organic pseudo‐rotaxanes are different to those of host‐guest compounds involving crown ethers and this may be valuable for the design of molecular machines.
Redox Behaviour and Redox Potentials of Dyes in Aqueous Buffers and Protic Ionic Liquids
Authors: Smith Lachlan O. , Thatcher Kathryn M. , Henderson‐Walshe Oscar J. , Crittenden Deborah L. 
Published: April 2024

AbstractOrganic dyes hold promise as inexpensive electrochemically‐active building blocks for new renewable energy technologies such as redox‐flow batteries and dye‐sensitised solar cells, especially if they display high oxidation and/or low reduction potentials in cheap, non‐flammable solvents such as water or protic ionic liquids. Systematic computational and experimental characterisation of a representative selection of acidic and basic dyes in buffered aqueous solutions and propylammonium formate confirm that quinoid‐type mechanisms impart electrochemical reversibility for the majority of systems investigated, including quinones, fused tricyclic heteroaromatics, indigo carmine and some aromatic nitrogenous species. Conversely, systems that generate longlived radical intermediates – arylmethanes, hydroquinones at high pH, azocyclic systems – tend to display irreversible electrochemistry, likely undergoing ring‐opening, dimerisation and/or disproportionation reactions.
Electronic Control of Polyproline II Helix Stability via the Identity of Acyl Capping Groups: the Pivaloyl Group Particularly Promotes PPII
Authors: Bhatt Megh R. , Zondlo Neal J. 
Published: April 2024

AbstractThe type II polyproline helix (PPII) is a fundamental secondary structure of proteins, important in globular proteins, in intrinsically disordered proteins, and at protein‐protein interfaces. PPII is stabilized in part by n→π* interactions between consecutive carbonyls, via electron delocalization between an electron‐donor carbonyl lone pair (n) and an electron‐acceptor carbonyl (π*) on the subsequent residue. We previously demonstrated that changes to the electronic properties of the acyl donor can predictably modulate the strength of n→π* interactions, with data from model compounds, in solution in chloroform, in the solid state, and computationally. Herein, we examined whether the electronic properties of acyl capping groups could modulate the stability of PPII in peptides in water. In X−PPGY‐NH2 peptides (X=10 acyl capping groups), the effect of acyl group identity on PPII was quantified by circular dichroism and NMR spectroscopy. Electron‐rich acyl groups promoted PPII relative to the standard acetyl (Ac−) group, with the pivaloyl and iso‐butyryl groups most significantly increasing PPII. In contrast, acyl derivatives with electron‐withdrawing substituents and the formyl group relatively disfavored PPII. Similar results, though lesser in magnitude, were also observed in X−APPGY‐NH2 peptides, indicating that the capping group can impact PPII conformation at both proline and non‐proline residues. The pivaloyl group was particularly favorable in promoting PPII. The effects of acyl capping groups were further analyzed in X–DfpPGY‐NH2 and X−ADfpPGY‐NH2 peptides, Dfp=4,4‐difluoroproline. Data on these peptides indicated that acyl groups induced order Piv‐ > Ac‐ > For‐. These results suggest that greater consideration should be given to the identity of acyl capping groups in inducing structure in peptides.
Asymmetric catalysis by chiral FLPs: A computational mini‐review
Authors: Patra Shanti Gopal 
Published: April 2024

AbstractSteric hindrance in Lewis acid (LA) and Lewis base (LB) obstruct the Lewis acid–base adduct formation, and the pair was termed as frustrated Lewis pair (FLP). In the past 16 years, the field of enantioselective catalysis by chiral FLPs has been slowly growing. It was shown that chiral LAs are significant as they are involved in the hydrogen transfer (HT) step to the imine, resulting in enantioselectivity. After H2 activation, the borohydride can exist in a number of plausible conformations and their stability is governed by the presence of noncovalent interaction through C–H····π and π····π interactions. However, LBs are not ideal for asymmetric induction as they compete with the imine substrate as a counter LB. Further, the proton transfer from chiral LB to the imine does not induce any chirality as chirality develops in the HT step. However, intramolecular FLPs with chiral scaffold are very efficient as they possess an optimum distance between LA and LB, which facilitates the H2 activation but precludes the adduct formation of the small molecules substrate with the LA component. This mini‐review summarizes computational investigation involving chiral LA and LB, and discusses intramolecular FLPs in the enantioselective catalysis.
Pd‐Catalyzed Dienylation of Propargylic Esters Enabling Highly Stereoselective Synthesis of Danishefsky‐Type Trisubstituted Dienes
Authors: Zhou Chen , Dai Mengfu , Yin Xiaoyu , Zhang Mingyue , Gu Weijin , Chen Liang‐An 
Published: April 2024

Comprehensive SummaryThe stereochemical synthesis of highly substituted Danishefsky‐type dienes remains unsolved in organic chemistry. We describe a simple and efficient approach for the stereoselective synthesis of Danishefsky‐type trisubstituted dienes from readily available propargylic esters via Pd‐catalyzed dienylation reaction through the key intermediate metallacyclobutene in a regio‐, chemo‐ and stereoselective fashion. This method facilitates a broad range of challenging trisubstituted dienes with a high level of stereocontrol. The synthetic utilities of oxygenated trisubstituted dienes have been demonstrated by the downstream chemistry, which notably undergoes Diels‐Alder reaction with a variety of electron‐deficient dienophiles to furnish multisubstituted cyclohexenes in good yields with excellent stereoselectivity.
Metal‐Organic Framework Nanozyme Enabling Dual‐Functional Photo‐Induced Charge Transfer and Biomimetic Precipitation for Advanced Organic Photoelectrochemical Transistor Bioanalysis
Authors: Xu Ke‐Xin , Yuan Cheng , Lou Hao , Chen Feng‐Zao , Zhang Ling , Chen Guangxu , Han De‐Man , Zhao Wei‐Wei 
Published: April 2024

Comprehensive SummaryWe report herein the first observation of MOF nanozyme enabling dual‐functional photo‐induced charge transfer and biomimetic precipitation for advanced organic photoelectrochemical transistor (OPECT) bioanalysis. Specifically, Fe/Co‐MIL‐88, serving simultaneously as the semiconductor and nanozyme, was explored as a dual‐functional gating module in OPECT. Upon light illumination, it could accelerate the charge transfer of the photogate to produce enhanced photo‐induced voltage. Meanwhile, its catalytic property could efficiently produce biomimetic precipitation to block the nanopores in Fe/Co‐MIL‐88 and thus alter the device characteristics. The generic bioanalytical potential of such a rationale was then demonstrated with an aptasensing assisted by magnetic separation. This work represents the first exploration of biomimetic precipitation from MOF nanozymes for generic OPECT bioanalysis, it is expected to attract more interest in various nanozymes for novel optoelectronic bioanalytics.
Chiral Lewis Base/Achiral Acid Co‐Catalyzed Atroposelective Sulfenylation of Pyrrole Derivatives: Construction of C—N Axially Chiral Sulfides
Authors: Yang Qin , Luo Hui‐Yun , Zhu Deng , Zhang Xin‐Yu , Ke Hua , Chen Zhi‐Min 
Published: April 2024

Comprehensive SummaryChiral BINAM‐derived selenide/achiral acid co‐catalyzed atroposelective electrophilic sulfenylation of pyrrole derivatives has been realized for the first time. A variety of C—N axially chiral sulfur‐containing pyrrole derivatives were readily obtained in moderate to good yields with moderate to excellent enantioselectivities. This catalytic system involves sequential desymmetrization and kinetic resolution.
Comparison of programmed death‐ligand 1 expression in adenocarcinoma and squamous cell carcinoma of the cervix in paraffin blocks of patients with cervical cancer
Authors: Hosseini Maryam Sadat , Shafizadeh Fatemeh , Bahremani Mohammad Hashemi , Farzaneh Farah , Ashrafganjoei Tahereh , Arab Maliheh , Talayeh Maryam , Jafari Fatemeh , Abdshah Alireza 
Published: April 2024

AbstractAimsCervical cancer (CC) is a common malignancy in women, predominantly caused by human papillomavirus. The most subtypes are adenocarcinomas (AC) and squamous cell carcinomas (SCC), which show various features and treatment responses. Programmed death‐ligand 1 (PD‐L1) and programmed cell death protein 1 (PD‐1) as Immune checkpoint molecules, play a role in immune evasion. We investigated PD‐L1 expression in AC and SCC of the cervix and explored its link to clinical characteristics.Methods and resultsThe present cross‐sectional research was done between 2016 and 2022 on samples in Shahid Beheshti University of Medical Sciences‐affiliated hospitals in Iran. Histological tissue samples of CCs (16 AC and 48 SCC) were assessed, and clinical information was obtained by reviewing their medical documents. PD‐L1 expression was evaluated by immunohistochemistry and we used the combined positive score. SCC cases showed a higher (not significant) PD‐L1 expression. The PD‐L1 expression and clinical characteristics were not significantly correlated in both subgroups.ConclusionAlthough SCC cases exhibited higher PD‐L1 expression, this difference was non‐significant. More investigations should highlight the role of PD‐L1 in CC and the potential benefits of immunotherapy.
Carbon‐Rich Plasma‐Deposited Silicon Oxycarbonitride Films Derived from 4‐(Trimethylsilyl)morpholine as a Novel Single‐Source Precursor
Authors: Ermakova Evgeniya , Tsyrendorzhieva Irina , Mareev Alexander , Pavlov Dmitry , Maslova Olga , Shayapov Vladimir , Maksimovskiy Eugene , Yushina Irina , Kosinova Marina 
Published: April 2024

Abstract4‐(trimethylsilyl)morpholine O(CH2CH2)2NSi(CH3)3 (TMSM) was investigated as a single‐source precursor for SiCNO films synthesis. Optical emission spectroscopy of plasma generated from TMSM/He, TMSM/H2, and TMSM/NH3 gas mixtures revealed the presence of N2, CH, H, CN, and CO species. The last two are suggested to be responsible for the lowering of carbon concentration in the films in comparison with the precursor. The refractive index ranged from 1.5 to 2.0, and bandgap varied from 2.0 to 4.6 eV, which pointed that some of the films can be used as antireflective coatings in silicon photovoltaic cell technologies and dielectric layers in electronic devices.
Aβ oligomers peak in early stages of Alzheimer's disease preceding tau pathology
Authors: Blömeke Lara , Rehn Fabian , Kraemer‐Schulien Victoria , Kutzsche Janine , Pils Marlene , Bujnicki Tuyen , Lewczuk Piotr , Kornhuber Johannes , Freiesleben Silka D. , Schneider Luisa‐Sophie , Preis Lukas , Priller Josef , Spruth Eike J. , Altenstein Slawek , Lohse Andrea , Schneider Anja , Fliessbach Klaus , Wiltfang Jens , Hansen Niels , Rostamzadeh Ayda , Düzel Emrah , Glanz Wenzel , Incesoy Enise I. , Butryn Michaela , Buerger Katharina , Janowitz Daniel , Ewers Michael , Perneczky Robert , Rauchmann Boris‐Stephan , Teipel Stefan , Kilimann Ingo , Goerss Doreen , Laske Christoph , Munk Matthias H. , Sanzenbacher Carolin , Spottke Annika , Roy‐Kluth Nina , Heneka Michael T. , Brosseron Frederic , Wagner Michael , Wolfsgruber Steffen , Kleineidam Luca , Stark Melina , Schmid Matthias , Jessen Frank , Bannach Oliver , Willbold Dieter , Peters Oliver 
Published: April 2024

AbstractINTRODUCTIONSoluble amyloid beta (Aβ) oligomers have been suggested as initiating Aβ related neuropathologic change in Alzheimer's disease (AD) but their quantitative distribution and chronological sequence within the AD continuum remain unclear.METHODSA total of 526 participants in early clinical stages of AD and controls from a longitudinal cohort were neurobiologically classified for amyloid and tau pathology applying the AT(N) system. Aβ and tau oligomers in the quantified cerebrospinal fluid (CSF) were measured using surface‐based fluorescence intensity distribution analysis (sFIDA) technology.RESULTSAcross groups, highest Aβ oligomer levels were found in A+ with subjective cognitive decline and mild cognitive impairment. Aβ oligomers were significantly higher in A+T− compared to A−T− and A+T+. APOE ε4 allele carriers showed significantly higher Aβ oligomer levels. No differences in tau oligomers were detected.DISCUSSIONThe accumulation of Aβ oligomers in the CSF peaks early within the AD continuum, preceding tau pathology. Disease‐modifying treatments targeting Aβ oligomers might have the highest therapeutic effect in these disease stages.Highlights
Using surface‐based fluorescence intensity distribution analysis (sFIDA) technology, we quantified Aβ oligomers in cerebrospinal fluid (CSF) samples of the DZNE‐Longitudinal Cognitive Impairment and Dementia (DELCODE) cohort
Aβ oligomers were significantly elevated in mild cognitive impairment (MCI)
Amyloid‐positive subjects in the subjective cognitive decline (SCD) group increased compared to the amyloid‐negative control group
Interestingly, levels of Aβ oligomers decrease at advanced stages of the disease (A+T+), which might be explained by altered clearing mechanisms
Cardiac sympathetic nerve activity trends after renal denervation in heart failure with preserved ejection fraction
Authors: Shiraki Tatsuya , Mizuno Hiroya , Kishi Takuya , Asakura Masanori , Asanoi Hidetsugu , Yasumura Yoshio , Sakata Yasushi 
Published: April 2024

AbstractThis case report describes the application of ultrasound renal denervation (uRDN) using the Paradise System in a patient with heart failure with preserved ejection fraction. Initially, the cardiac sympathetic nerve activity of the patient exhibited a late heart/mediastinum (H/M) ratio of 2.00 and a washout rate of 66.0% by cardiac iodine‐123 metaiodobenzylguanidine (123I‐MIBG) scintigraphy. Subsequently, the patient underwent transfemoral uRDN targeting the left, right upper, and right lower renal arteries. At the 6 month follow‐up, no significant change was observed in 123I‐MIBG findings; however, the estimated stressed blood volume (eSBV) decreased from 1722 to 1029 mL/70 kg. At 18 months, 123I‐MIBG findings improved, with the late H/M ratio reaching 2.76 and the washout rate decreasing to 43.1%. This case report highlights the potential of uRDN in reducing eSBV within 6 months and subsequently improving cardiac sympathetic nerve activity at the 18 month follow‐up.
Stoichiometric and Catalytic Reduction of Carbon Dioxide by a Sterically Encumbered Amidinato Magnesium Hydride
Authors: Huadsai Wimonsiri , Vendier Laure , Görls Helmar , Magna Lionel , Bontemps Sébastien , Westerhausen Matthias 
Published: April 2024

AbstractA sterically encumbered dinuclear amidinato magnesium hydride 3 with bridging hydrido ligands was synthesized from the metalation of the corresponding amidine 1 with dibutylmagnesium and subsequent treatment with phenylsilane. This complex reacts stoichiometrically with 1 atm of carbon dioxide at room temperature in tetrahydrofuran (THF) to the corresponding bis(thf) adduct of the dinuclear formate complex 4‐2 thf with bridging formate anions. This complex is stable in THF at 60 °C for more than 16 hours but decomposes into the amidine 1 upon removal of ligated thf ligands. Complex 3 efficiently catalyzes the reduction of carbon dioxide with 9‐BBN, yielding bis(boryl)acetal (R2BO)2CH2, and with silanes H4‐nSiPhn (n=1, 2, and 3). The bis(silyl)acetal is quantitatively accessible for Ph3SiH (n=3) whereas during the reduction of CO2 with hydrogen‐richer silanes (n=1, 2) siloxanes form and methane evolves.
Selenosulfones, a Meetup of Chalcogens: A Journey Into Their Recent Chemistry
Authors: Bagnoli Luana , Rosati Ornelio , Marini Francesca , Santi Claudio , Sancineto Luca 
Published: April 2024

AbstractA mini review focused on the chemistry of selenosulfones reported since 2019 is here presented. Initially, methods aimed to the preparation of such moiety are discussed. Successively 1,2‐, 1,3‐, 1,4‐ and 1,7‐addition reactions to C−C single and multiple bonds are illustrated. The forth chapter focuses on electrophilic aromatic substitutions. The fifth chapter deals with C−H functionalizations while the sixth one shows the reactions with aryl diazonium salts or its precursors. The radical coupling with redox active reagents, is the subject of section seventh. Selenosulfones challenged in nucleophilic substitutions and in reactions with phosphorus‐containing compounds are shown in chapter eight and nine followed by the conclusions and perspectives section.
Life cycle assessment of lead‐free potassium sodium niobate versus lead zirconate titanate: Energy and environmental impacts
Authors: Wu Yanqi , Soon Pak‐Sheng , Lu Jing‐Tong , Zhou Jinling , Liu Yi‐Xuan , Guo Zhaohui , Wang Ke , Gong Wen 
Published: April 2024

AbstractOver the years, lead‐based piezoelectric ceramics found extensive use in vital fields such as sensors and actuators. Despite their exceptional electromechanical properties, lead‐containing materials pose severe environmental risks and foster a new era of lead‐free piezoelectric materials after decades of research. However, recent comparative assessments of potassium sodium niobate (KNN) versus lead zirconate titanate (PZT) piezoelectric materials proposed that the environmental damage already presented before use due to raw material extraction and processing, invoking concerns on the true greenness of the lead‐free alternatives. Nevertheless, many other factors deserve further consideration, for example, reference geometry and life cycle stage. Herein, the comprehensive life cycle assessment is undertaken on PZT and KNN‐based ceramics with a unit volume of 0.001 m3 from cradle to gate. Results show that PZT exhibits higher negative impacts than KNN‐based counterparts, attributed to lead extraction, processing, and associated environmental emissions. Across primary quantitative impact indicators from toxicity, environmental, and resource aspects, KNN‐based ceramics impose fewer risks on the environment and human health, with the overall impact being only 28% of PZT ceramics. Still, more efficient methods are required for KNN‐based ceramics to reduce the high energy consumption and emission during extraction and purification of raw material Nb2O5. This work not only offers critical insights for material development but also serves as a multifaceted reference for advanced fabrication technologies.image
Ecological Risk Assessment of Three Pesticide Additives in Soil and Application to the Remediation of Contaminated Soil
Authors: Li Ying , Zhang Jing , Wang Wenqiang , Lu Yongze , Sun Liwei , Zhang Yimin 
Published: April 2024

Abstract
Pesticide additives (PAs) are auxiliary ingredients added to the pesticide manufacturing and use processes, constituting 1% to 99% of the pesticide and often composed of benzene and chlorinated hydrocarbons. We selected three typical PAs, toluene, chloroform, and trichloroethylene, to evaluate their retention function toxicity and ecological risk in soil. Soil immobilization techniques and aquatic model organisms were used to demonstrate the effectiveness of the immobilized soil method to determine the ecological risk of chemicals. The 48-h median lethal concentrations of toluene, chloroform, and trichloroethylene alone in spiked soil on Daphnia magna were 10.5, 2.3, and 1.1 mg/L (medium, high, and high toxicity, respectively). The toxicity of the three-PA mixtures showed an antagonistic effect. The risk levels of toluene, chloroform, and trichloroethylene in the soil were evaluated as moderate to high, low to high, and high risk, respectively. The toxicity of two pesticide-contaminated sites in the Yangtze River Delta before and after remediation was successfully evaluated by immobilized soil technology. The toxicity of two soil sampling points was reduced from medium toxic to low toxic and no toxic, respectively, after remediation. The results of our study give a rationale for and prove the validity of the aquatic model organisms and soil immobilization techniques in assessing the soil retention functions toxicity of PAs. Environ Toxicol Chem 2024;43:1677–1689. © 2024 SETAC
Evaluating the impact of the degree of extranodal extension on outcomes in locally advanced oral cavity cancer
Authors: Yalamanchali Anirudh , Griffith Christopher , Reddy Chandana A. , Koyfman Shlomo A. , Woody Neil M. , Campbell Shauna R. , Silver Natalie , Scharpf Joseph , Lorenz Robert R. , Prendes Brandon , Ku Jamie A. , Lamarre Eric , Geiger Jessica L. 
Published: April 2024

AbstractBackgroundEvaluate whether extranodal extension (ENE) extent impacts outcomes in patients with oral cavity squamous cell carcinoma (OCSCC).MethodsFrom an institutional database, patients with OCSCC and pathologic ENE who received adjuvant treatment were included. Surgical slides were reviewed to confirm ENE extent.Multivariable Cox regression was used to relate patient/treatment characteristics with disease‐free survival (DFS) and overall survival (OS). ENE was analyzed as both a dichotomous and continuous variable.ResultsA total of 113 patients were identified. Between major (>2 mm) versus minor ENE (≤2 mm), there was no significant difference in DFS (HR 1.18, 95%CI 0.72–1.92, p = 0.51) or OS (HR 1.17, 95%CI 0.70–1.96, p = 0.55). There was no significant association between ENE as a continuous variable and DFS (HR 0.97 per mm, 95%CI 0.87–1.4, p = 0.96) or OS (HR 0.96 per mm, 95%CI 0.83–1.11, p = 0.58).ConclusionNo significant relationship was seen between ENE extent and DFS or OS in individuals with OCSCC.