bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis, Characterization and Interconversion of p–Tolylsulfone‐Functionalized Norbornadiene/Quadricyclane Couples
Authors: Krappmann Daniel , Hirsch Andreas 
Published: July 2024

AbstractWe report the synthesis and characterization of library of new 2,3–disubstituted norbornadiene/quadricyclane couples. For the first time, the para–tolylsulfone moiety was employed as electron–withdrawing substituent in combination with a variety of different electron donors as counterparts. Comprehensive characterization was conducted for every interconversion couple. By comparison with structurally related molecules published before we established the tosyl moiety as suitable alternative to previously investigated ester functionalities by providing similar photophysical properties. The photo–induced interconversion behavior was investigated via UV/Vis‐ and NMR–spectroscopy. The UV/Vis experiments were carried out exclusively in acetonitrile, whereas several solvents were investigated in the NMR studies. A detailed description and comparison of the isomerization behavior is provided, while examining relevant optical properties like λmax and λonset. Thereby, an enhanced red‐shift up to λmax=394 nm combined with an λonset value of 469 nm could be generated which is necessary for potential applications.
Improved Electrochemical Peptide Synthesis Enabled by Electron‐Rich Triaryl Phosphines
Authors: Shinjo‐Nagahara Shingo , Okada Yohei , Hiratsuka Goki , Kitano Yoshikazu , Chiba Kazuhiro 
Published: July 2024

AbstractWhile remarkable progress has been made in the development of peptide medicines, many problems related to peptide synthesis remain unresolved. Previously, we reported electrochemical peptide synthesis using a phosphine as a potentially recyclable coupling reagent. However, there was room for improvement from the point of view of reaction efficiency, especially in the carboxylic acid activation step and the peptide bond formation step. To overcome these challenges, we searched for the optimal phosphine. Among phosphines with various electronic properties, we found that electron‐rich triaryl phosphines improved the reaction efficiency. Consequently, we successfully performed electrochemical peptide synthesis on sterically hindered and valuable amino acids. We also synthesized oligopeptides that were challenging with our previous method. Finally, we examined the effect of substituents on the phosphine cations, and gained some insights into reactivity, which will aid researchers designing reactions involving phosphine cations.
Poly[2]catenane Gels Based on Sequential Assembly of Small Molecules†
Authors: Zhang Hanwei , Li Jinsa , Hu Ziqing , Ji Xiaofan 
Published: July 2024

Comprehensive SummaryPolycatenane gels have attracted extensive attention due to their high degree of freedom and mobility. However, the syntheses of poly[2]catenane gels reported to date all rely on the polymer as the backbone. Herein, we prepared poly[2]catenane gels based on entirely sequential assembly of small molecules. Monomer M1 with two unclosed rings was first prepared, which self‐assembled to form supramolecular polymers (SPs) via hydrogen bonding and π‐π interactions. Upon adding small molecule monomers M2 and M3 with aldehyde groups, ring closing of SPs occurred because the amino groups in the SPs reacted with M2 to form imine bonds. In addition, M3, which had twice the number of aldehyde groups as M2, enabled SPs to ring‐close, causing the proceeding of crosslinking process at the same time. Thus linear SPs were transformed into poly[2]catenane gel networks. Due to the presence of hydrogen bonds in the poly[2]catenane gel, the gel also possessed stimulus responsiveness and self‐healing properties.
Understanding the Temperature Effect on Carbon‐Carbon Coupling during CO2 and CO Electroreduction in Zero‐Gap Electrolyzers†
Authors: Zhuansun Mengjiao , Wang Xuan , Teng Wenzhi , Wang Yuhang 
Published: July 2024

Comprehensive SummaryCu‐catalyzed electrochemical CO2 reduction reaction (CO2RR) and CO reduction reaction (CORR) are of great interest due to their potential to produce carbon‐neutral and value‐added multicarbon (C2+) chemicals. In practice, CO2RR and CORR are typically operated at industrially relevant current densities, making the process exothermal. Although the increased operation temperature is known to affect the performance of CO2RR and CORR, the relationship between temperatures and kinetic parameters was not clearly elaborated, particularly in zero‐gap reactors. In this study, we detail the effect of the temperature on Cu‐catalyzed CO2RR and CORR. Our electrochemical and operando spectroscopic studies show that high temperatures increase the activity of CO2RR to CO and CORR to C2H4 by enhancing the mass transfer of CO2 and CO. As the rates of these two processes are highly influenced by reactant diffusion, elevating the operating temperature results in high local CO2 and CO availability to accelerate product formation. Consequently, the *CO coverage in both cases increases at higher temperatures. However, under CO2RR conditions, *CO desorption is more favorable than carbon‐carbon (C—C) coupling thermodynamically at high temperatures, causing the reduction in the Faradaic efficiency (FE) of C2H4. In CORR, the high‐temperature‐augmented CO diffusion overcomes the unfavorable adsorption thermodynamics, increasing the probability of C—C coupling.
Survival trends among patients with metastatic non–small cell lung cancer before and after the approval of immunotherapy in the United States: A Surveillance, Epidemiology, and End Results database–based study
Authors: Wang Yating , Kondrat Kyle , Adhikari Janak , Nguyen Quynh , Yu Qian , Uprety Dipesh 
Published: July 2024

AbstractBackgroundIn 2015, the US Food and Drug Administration approved nivolumab as the first immunotherapy for patients with advanced non–small cell lung cancer (NSCLC). However, population‐based survival benefit studies after the introduction of immunotherapy in lung cancer are lacking. This study examined overall survival (OS) and cancer‐specific survival in patients with NSCLC in the pre immunotherapy and immunotherapy eras.MethodsThis study used the Surveillance, Epidemiology, and End Results database, which spanned 17 registries from 2000 to 2020. Two cohorts were delineated: preimmunotherapy (2010–2014) and immunotherapy (2015–2020), which coincided with nivolumab’s approval.ResultsThis study included 191,802 patients, 90,807 in the preimmunotherapy era and 100,995 in the immunotherapy era. OS was significantly higher in the immunotherapy era, as shown by Kaplan–Meier curves (1‐year OS, 40.1% vs. 33.5%; 3‐year OS, 17.8% vs. 11.7%; 5‐year OS, 10.7% vs. 6.8%; median OS, 8 vs. 7 months; p < .001 by log‐rank test). Similarly, cancer‐specific survival improved in the immunotherapy era (1‐year survival, 44.0% vs. 36.8%; 3‐year survival, 21.7% vs. 14.4%; 5‐year survival, 14.3% vs. 9.0%; median OS, 10 vs. 8 months; p < .001 by log‐rank test). Survival rates were significantly better in the immunotherapy era, as confirmed by multivariate analysis with a Cox proportional hazards model after adjusting for age, sex, race, income, and geographical area (adjusted hazard ratio, 0.830; 95% CI, 0.821–0.840; p < .001).ConclusionsIn summary, the survival rate of patients with metastatic NSCLC has improved since the introduction of immunotherapy.
A phase 2 study of a brachyury‐targeting vaccine in combination with radiation therapy for the treatment of advanced chordoma
Authors: Cote Gregory M. , Conley Anthony P. , Attia Steven , Van Tine Brian A. , Seetharam Mahesh , Chen Yen‐Lin , Gafoor Zarina , Heery Christopher , Pico‐Navarro Cesar , Adams Tatiana 
Published: July 2024

AbstractBackgroundThis was a single‐arm, phase 2 clinical trial of Bavarian Nordic (BN)‐Brachyury vaccine plus radiotherapy (RT) designed to determine the objective response rate (ORR), progression‐free survival (PFS), and safety of the combination in chordoma.MethodsA total of 29 adult patients with advanced chordoma were treated with two subcutaneous priming vaccine doses of modified vaccinia Ankara‐Bavarian Nordic (MVA‐BN)‐Brachyury and one vaccine dose of fowlpox virus (FPV)‐Brachyury before RT. After RT, booster vaccinations were given with FPV‐Brachyury every 4 weeks for 4 doses, then every 12 weeks (week 110). A minimum RT dose of >8 Gy in one fraction for each target was required. Response was evaluated by modified Response Evaluation Criteria in Solid Tumors 1.1 (mRECIST), where only radiated lesions were considered targets, and by standard RECIST 1.1 in a subset of patients.ResultsTwo of 26 evaluable patients experienced durable partial response (PR) (ORR of 7.7%; 90% confidence interval [CI], 2.6–20.8]) by mRECIST 1.1. A total of 21 patients (80.8%; 90% CI, 65.4–90.3) had stable disease, and three patients (11.5%; 90% CI, 4.7–25.6) had progressive disease as best response per mRECIST 1.1. Median PFS was not reached during the study.ConclusionsThis trial confirms the safety of BN‐Brachyury and RT. Although the study did not meet the predefined study goal of four responses in 29 patients, we did observe two PRs and a PFS of greater than 2 years. For a vaccine‐based study in chordoma, an ultra‐rare disease where response rates are low, a randomized study or novel trial designs may be required to confirm activity.
Non‐orthogonal multiple access‐based task processing and energy optimization in vehicular edge computing networks
Authors: Shi Lei , Li Zepeng , Zhao Shuangliang , Fan Yuqi , Qian Dingjun 
Published: July 2024

SummaryVehicular edge computing (VEC) is envisioned as a promising approach to process explosive vehicle tasks, where vehicles can choose to upload tasks to nearby edge nodes for processing. However, since the communication between vehicles and edge nodes is via wireless network, which means the channel condition is complex. Moreover, in reality, the arrival time of each vehicle task is stochastic, so efficient communication methods should be designed for VEC. As one of the key communication technologies in 5G, non‐orthogonal multiple access (NOMA) can effectively increase the number of simultaneous transmission tasks and enhance transmission performance. In this article, we design a NOMA‐based task allocation scheme to improve the VEC system. We first establish the mathematical model and divide the allocation of tasks into two processes: the transmission process and the computation process. In the transmission process, we adopt the NOMA technique to upload the tasks in batches. In the computation process, we use a high response‐ratio strategy to determine the computation order. Then we define the optimization objective as maximizing task completion rate and minimizing task energy consumption, which is an integer nonlinear problem with lots of integer variables and cannot be solved directly. Through further analysis, we design a heuristics algorithm which we name as the AECO (average energy consumption optimization) algorithm. By using the AECO, we obtain the optimal allocation strategy by constantly adjusting the optimal variables. Simulation results demonstrate that our algorithm has a significant number of advantages.
Tricyclic 1,4‐Diphosphinines: Local vs. Global Aromaticity
Authors: Kalisch Tim , Brehm Philipp C. , Streubel Rainer 
Published: July 2024

Abstract1D and 2D
(Sigma only model) calculations were performed on recently established tricyclic 1,4‐diphosphinines as well as related benzene and pyrazine derivatives. The study was extended to evaluate the effect of the fused rings on the overall aromatic properties with a special focus on functional groups such as carbenes. The effect of non‐aromatic heterocycles on the local ring current of the central ring is small, while aromatic heterocycles (e. g. NHC, imidazolium) lead to a global aromaticity. A higher sulfur content of the adjacent five‐membered rings reduces the central ring current. The comparison to related tricyclic benzene and pyrazine derivatives showed that the 1,4‐diphosphinine systems resemble more closely the situation in the benzene derivatives than the pyrazines. The effect of charged systems was studied using bis(TTF)‐fused 1,4‐diphosphinines and, according to
values, the neutral form doesn't possess significant aromaticity but the tetracation resembles the global aromatic situation observed for other heterocycles in this study.
Optical Emission Spectra of Molecular Excitonic Polariton Computed at the First‐Principles Level QED‐TDDFT
Authors: Deng Shanhao , Yang Junjie , Shao Yihan , Ou Qi , Shuai Zhigang 
Published: July 2024

AbstractIn microcavity, strong coupling between light and molecules leads to the formation of hybrid excitations, i. e., the polaritons, or exciton‐polaritons. Such coupling may alter the energy landscape of the system and the optical properties of the material, making it an effective approach for controlling the light emission from molecular materials. However, due to the complexity of vibrational modes, spectroscopic calculations for organic exciton‐polaritons remain to be challenging. In this work, based on the linear‐response quantum‐electrodynamical time‐dependent density functional theory (QED‐TDDFT), we employ the thermal vibrational correlation function (TVCF) formalism to calculate the molecular optical spectrum of the lower polaritons (LP) at first‐principles level for three molecules, i. e., anthracene, distyrylbenzenes (DSB), and rubrene. The polaron decoupling effect is confirmed from our first‐principles computations. The theoretical emission spectra of LP provide new insights for aiding molecular and device design in microcavities that are otherwise hindered due to the lack of vibrational information.
Towards Sustainable Production of Polybutylene Adipate Terephthalate: Non‐Biological Catalytic Syntheses of Biomass‐Derived Constituents
Authors: Lee Jechan , Park Chanyeong , Fai Tsang Yiu , Andrew Lin Kun‐Yi 
Published: July 2024

AbstractRenewable chemicals, which are made from renewable resources such as biomass, have attracted significant interest as substitutes for natural gas‐ or petroleum‐derived chemicals to enhance the sustainability of the chemical and petrochemical industries. Polybutylene adipate terephthalate (PBAT), which is a copolyester of 1,4‐butanediol (1,4‐BDO), adipic acid (AA), and dimethyl terephthalate (DMT) or terephthalic acid (TPA), has garnered significant interest as a biodegradable polymer. This study assesses the non‐biological production of PBAT monomers from biomass feedstocks via heterogeneous catalytic reactions. The biomass‐based catalytic routes to each monomer are analyzed and compared to conventional routes. Although no fully commercialized catalytic processes for direct conversion of biomass into 1,4‐BDO, AA, DMT, and TPA are available, emerging and promising catalytic routes have been proposed. The proposed biomass‐based catalytic pathways toward 1,4‐BDO, AA, DMT, and TPA are not yet fully competitive with conventional fossil fuel‐based pathways mainly due to high feedstock prices and the existence of other alternatives. However, given continuous technological advances in the renewable production of PBAT monomers, bio‐based PBAT should be economically viable in the near future.
Electrochemical CO2 Reduction to Multicarbon Products on Non‐Copper Based Catalysts
Authors: Huang Jiayi , Liu Qianwen , Huang Jianmei , Xu Ming , Lai Wenchuan , Gu Zhiyuan 
Published: July 2024

AbstractElectrochemical CO2 reduction reaction (eCO2RR) to value‐added multicarbon (C2+) products offers a promising approach for achieving carbon neutrality and storing intermittent renewable energy. Copper (Cu)‐based electrocatalysts generally play the predominant role in this process. Yet recently, more and more non‐Cu materials have demonstrated the capability to convert CO2 into C2+, which provides impressive production efficiency even exceeding those on Cu, and a wider variety of C2+ compounds not achievable with Cu counterparts. This motivates us to organize the present review to make a timely and tutorial summary of recent progresses on developing non‐Cu based catalysts for CO2‐to‐C2+. We begin by elucidating the reaction pathways for C2+ formation, with an emphasis on the unique C−C coupling mechanisms in non‐Cu electrocatalysts. Subsequently, we summarize the typical C2+‐involved non‐Cu catalysts, including ds‐, d‐ and p‐block metals, as well as metal‐free materials, presenting the state‐of‐the‐art design strategies to enhance C2+ efficiency. The system upgrading to promote C2+ productivity on non‐Cu electrodes covering microbial electrosynthesis, electrolyte engineering, regulation of operational conditions, and synergistic co‐electrolysis, is highlighted as well. Our review concludes with an exploration of the challenges and future opportunities in this rapidly evolving field.
Numerical investigation of thermal damage in rocks under high‐voltage electric pulse
Authors: Zhu Xiaohua , Liu Siqi , Liu Weiji , Zhou Xin , Tang Wuji 
Published: July 2024

AbstractThe high‐voltage electric pulse fracturing (HVEPF) technology represents a novel and highly promising approach in rock fracturing. The investigation of thermal damage inflicted upon rocks by high‐voltage electrical pulses under multi‐physical field coupling is of great significance in the development of deep geothermal energy. This study establishes a damage model for rocks under electric fragmentation conditions by integrating electric field, heat transfer field, and solid mechanics field. Based on the developed damage model, the insulating properties, temperature variations, and forms of damage of rocks during electric fracturing are explored. Subsequently, the influence of voltage on rock damage status is investigated. The findings reveal that damage to the rock does not occur immediately after electrical breakdown; rather, it increases with the growth of current and temperature within the breakdown channel. Initial damage occurs at the ends of the breakdown channel, followed closely by damage in the central region of the channel. The predominant form of damage in rocks is tensile failure, with shear failure playing a secondary role, and the volume of damage increases with voltage. These results elucidate the characteristics of rock damage during electric fracturing, providing valuable insights for the engineering application of electric fracturing techniques.
Unraveling spatial heterogeneity of soil legacy phosphorus in subtropical grasslands
Authors: Qiu Jiangxiao , Zhi Ran , Boughton Elizabeth H. , Li Haoyu , Henderson Charlotte R. B. , Petticord Daniel F. , Sparks Jed P. , Saha Amartya , Reddy K. Ramesh 
Published: July 2024

AbstractHumans have profoundly altered phosphorus (P) cycling across scales. Agriculturally driven changes (e.g., excessive P‐fertilization and manure addition), in particular, have resulted in pronounced P accumulations in soils, often known as “soil legacy P.” These legacy P reserves serve as persistent and long‐term nonpoint sources, inducing downstream eutrophication and ecosystem services degradation. While there is considerable scientific and policy interest in legacy P, its fine‐scale spatial heterogeneity, underlying drivers, and scales of variance remain unclear. Here we present an extensive field sampling (150‐m interval grid) and analysis of 1438 surface soils (0–15 cm) in 2020 for two typical subtropical grassland types managed for livestock production: Intensively managed (IM) and Semi‐natural (SN) pastures. We ask the following questions: (1) What is the spatial variability, and are there hotspots of soil legacy P? (2) Does soil legacy P vary primarily within pastures, among pastures, or between pasture types? (3) How does soil legacy P relate to pasture management intensity, soil and geographic characteristics? and (4) What is the relationship between soil legacy P and aboveground plant tissue P concentration? Our results showed that three measurements of soil legacy P (total P, Mehlich‐1, and Mehlich‐3 extractable P representing labile P pools) varied substantially across the landscape. Spatial autoregressive models revealed that soil organic matter, pH, available Fe and Al, elevation, and pasture management intensity were crucial predictors for spatial patterns of soil P, although models were more reliable for predicting total P (68.9%) than labile P. Our analysis further demonstrated that total variance in soil legacy P was greater in IM than SN pastures, and intensified pasture management rescaled spatial patterns of soil legacy P. In particular, after controlling for sample size, soil P was extremely variable at small scales, with variance diminished as spatial scale increased. Our results suggest that broad pasture‐ or farm‐level best management practices may be limited and less efficient, especially for more IM pastures. Rather, management to curtail soil legacy P and mitigate P loading and losses should be implemented at fine scales designed to target spatially distinct P hotspots across the landscape.
Long‐distance swimming by African lions in Uganda
Authors: Braczkowski A. , Ochse L. , Atukwatse B. , Cornille O. , O'Bryan C. , Lindsey P. , Kotze R. , Gibson L. , Biggs D. 
Published: July 2024

AbstractEarth's most imperiled and iconic wildlife are facing tough decisions under increasing human pressure and limited resources. Swimming across rivers and water bodies filled with high densities of predators may be one such example. In African lions Panthera leo, previous water crossings (recorded in the peer‐reviewed and gray literature, on film, and found using Google Search, and YouTube) have recorded distances ranging from <10 to 100 m, with some resulting in mortality by Nile Crocodiles Crocodylis niloticus. However, we observed a coalition of male lions swimming >1 km across Uganda's Kazinga channel located in the Queen Elizabeth National Park six times, and recorded this behavior on film on February 1st 2024. We speculate that three factors could be driving these lions to take long‐distance swims with a high density of crocodiles and hippos Hippopotamus amphibius, namely (1) the lack of lionesses in this ecosystem, (2) intraspecific fights over territory with other male coalitions, and (3) the only other land connection giving lions access to the peninsula is a small road bridge with a strong human presence.
Distribution patterns of soil bacteria, fungi, and protists emerge from distinct assembly processes across subcommunities
Authors: Kayiranga Alexis , Isabwe Alain , Yao Haifeng , Shangguan Huayuan , Coulibaly Justin Louis Kafana , Breed Martin , Sun Xin 
Published: July 2024

AbstractEnvironmental change exerts a profound effect on soil microbial domains—including bacteria, fungi, and protists—that each perform vital ecological processes. While these microbial domains are ubiquitous and extremely diverse, little is known about how they respond to environmental changes in urban soil ecosystems and what ecological processes shape them. Here we investigated the community assembly processes governing bacteria, fungi, and protists through the lens of four distinct subcommunities: abundant, conditionally rare, conditionally abundant, and rare taxa. We show that transient taxa, including the conditionally rare and conditionally rare or abundant taxa, were the predominant subcommunities. Deterministic processes (e.g., environmental filtering) had major roles in structuring all subcommunities of fungi, as well as conditionally rare and abundant protists. Stochastic processes had strong effects in structuring all subcommunities of bacteria (except rare taxa) and conditionally rare protists. Overall, our study underscores the importance of complementing the traditional taxonomy of microbial domains with the subcommunity approach when investigating microbial communities in urban soil ecosystems.