bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biocatalysis with In‐Situ Product Removal Improves p‐Coumaric Acid Production
Authors: Virklund Alexander , Nielsen Alex Toftgaard , Woodley John M. 
Published: May 2024

AbstractNatural and pure p‐coumaric acid has valuable applications, and it can be produced via bioprocessing. However, fermentation processes have so far been unable to provide sufficient production metrics, while a biocatalytic process decoupling growth and production historically showed much promise. This biocatalytic process is revisited in order to tackle product inhibition of the key enzyme tyrosine ammonia lyase. In situ product removal is proposed as a possible solution, and a polymer/salt aqueous two‐phase system is identified as a suitable system for extraction of p‐coumaric acid from an alkaline solution, with a partition coefficient of up to 13. However, a 10 % salt solution was found to reduce tyrosine ammonia lyase activity by 19 %, leading to the need for a more dilute system. The cloud points of two aqueous two‐phase systems at 40 °C and pH 10 were found to be 3.8 % salt and 9.5 % polymer, and a 5 % potassium phosphate and 12.5 % poly(ethylene glycol‐ran‐propylene glycol) mW~2500 system was selected for in situ product removal. An immobilized tyrosine ammonia lyase biocatalyst in this aqueous two‐phase system produced up to 33 g/L p‐coumaric acid within 24 hours, a 1.9‐fold improvement compared to biocatalysis without in situ product removal.
Impact of Protein Corona Formation and Polystyrene Nanoparticle Functionalisation on the Interaction with Dynamic Biomimetic Membranes Comprising of Integrin
Authors: Janke Una , Geist Norman , Weilbeer Emma , Levin Wanda , Delcea Mihaela 
Published: May 2024

AbstractPlastics, omnipresent in the environment, have become a global concern due to their durability and limited biodegradability, especially in the form of microparticles and nanoparticles. Polystyrene (PS), a key plastic type, is susceptible to fragmentation and surface alterations induced by environmental factors or industrial processes. With widespread human exposure through pollution and diverse industrial applications, understanding the physiological impact of PS, particularly in nanoparticle form (PS‐NPs), is crucial. This study focuses on the interaction of PS‐NPs with model blood proteins, emphasising the formation of a protein corona, and explores the subsequent contact with platelet membrane mimetics using experimental and theoretical approaches. The investigation involves αIIbβ3‐expressing cells and biomimetic membranes, enabling real‐time and label‐free nanoscale precision. By employing quartz‐crystal microbalance with dissipation monitoring studies, the concentration‐dependent cytotoxic effects of differently functionalised ~210 nm PS‐NPs on HEK293 cells overexpressing αIIbβ3 are evaluated in detail. The study unveils insights into the molecular details of PS‐NP interaction with supported lipid bilayers, demonstrating that a protein corona formed in the presence of exemplary blood proteins offers protection against membrane damage, mitigating PS‐NP cytotoxicity.
Osthole exhibits the remedial potential for polycystic ovary syndrome mice through Nrf2‐Foxo1‐GSH‐NF‐κB pathway
Authors: Jin Shan , Wang Yu‐Si , Huang Ji‐Cheng , Wang Ting‐Ting , Li Bai‐Yu , Guo Bin , Yue Zhan‐Peng 
Published: May 2024

AbstractPolycystic ovary syndrome (PCOS) is the primary cause of female infertility with a lack of universal therapeutic regimen. Although osthole exhibits numerous pharmacological activities in treating various diseases, its therapeutic effect on PCOS is undiscovered. The present study found that application of osthole improved the symptoms of PCOS mice through preventing ovarian granulosa cells (GCs) production of more estrogen and alleviating the liberation of pro‐inflammatory cytokine interleukin (IL)‐1β, IL‐6, and tumor necrosis factor alpha. Meanwhile, osthole enhanced ovarian antioxidant capacity and alleviated intracellular reactive oxygen species (ROS) accumulation with a concurrent attenuation for oxidative stress, while intervention of antioxidant enzymic activity and glutathione (GSH) synthesis neutralized the salvation of osthole on GCs secretory disorder and chronic inflammation. Further analysis revealed that osthole restored the expression of nuclear factor erythroid 2‐related factor 2 (Nrf2) and forkhead box O 1 (Foxo1) whose repression antagonized the amelioration of osthole on the insufficiency of antioxidant capacity and accumulation of ROS. Moreover, Nrf2 served as an intermedium to mediate the regulation of osthole on Foxo1. Additionally, osthole restricted the phosphorylation of IκBα and nuclear factor kappa B (NF‐κB) subunit p65 by DHEA and weakened the transcriptional activity of NF‐κB, but this effectiveness was abrogated by the obstruction of Nrf2 and Foxo1, whereas adjunction of GSH renewed the redemptive effect of osthole on NF‐κB whose activation caused an invalidation of osthole in rescuing the aberration of GCs secretory function and inflammation response. Collectively, osthole might relieve the symptoms of PCOS mice via Nrf2‐Foxo1‐GSH‐NF‐κB pathway.
Treatment of tardive dyskinesia with clonazepam: A case report
Authors: Chhetri Bikram , Gyeltshen Dawa 
Published: May 2024

Key Clinical MessageClonazepam has some evidence in the treatment of tardive dyskinesia. It can be used as an alternative treatment option in situations where vesicular monoamine transporter 2 inhibitors are not available or when it is not feasible to use them.
Regiodivergent Synthesis of 4‐ and 5‐Sulfenyl Oxazoles from Alkynyl Thioethers
Authors: Sekar Prakash , Gupta Aniket , English Laura E. , Rabbitt Clare E. , Male Louise , Jupp Andrew R. , Davies Paul W. 
Published: May 2024

AbstractThe regiodivergent synthesis of 4‐ and 5‐sulfenyl oxazoles from 1,4,2‐dioxazoles and alkynyl thioethers has been achieved. Gold‐catalysed conditions are used to favour the formation of 5‐sulfenyl oxazoles via β‐selective attack of the nitrenoid relative to the sulfenyl group. In contrast, 4‐sulfenyl oxazoles are formed by α‐selective reaction under Brønsted acid conditions from the same substrates. The nature of stabilising gold‐sulfur interactions have been investigated by natural bond orbital analysis, showing that the S→Au interactions are significantly stronger in the intermediate that favours the 5‐sulfenyl oxazoles. A kinetic survey identifies catalyst inhibition processes. This study into the regiodivergent methods includes the development of telescoped annulation‐oxidation protocols for regioselective access to oxazole sulfoxides and sulfones.
Photocatalytic C(sp3)‐H gem‐Difluoroallylation and Alkylation with Alkenes via a Base‐Assisted Formal 1,2‐Hydrogen Atom Transfer of Amidyl Radicals
Authors: Tang Meifang , Feng Bingbing , Bao Yanyang , Xu Zhongtian , Huang Chao , Zheng Hanliang , Zhu Gangguo , Wang Yanan , Yuan Zheliang 
Published: May 2024

Comprehensive SummaryCompared to well‐established 1,5‐HAT of N‐centered radicals, the synthetic applications of 1,2‐HAT process were scarce due to the high barrier and constrained three‐membered transition state. Here, we have developed a novel C(sp3)‐H gem‐difluoroallylation via a base assisted formal 1,2‐HAT of amidyl radicals with the reductive quenching cycle of photocatalyst. This transformation enables the efficient formation of α‐aminoalkyl radicals via 1,2‐HAT and showcases good functional group tolerance. Our preliminary mechanistic experiments, along with Density Functional Theory (DFT) calculations demonstrate the feasibility of 1,2‐HAT of amidyl radicals, especially when assisted by a base. Furthermore, our method also succeeds in the Giese addition of electron‐deficient alkenes as well as styrene.
Hyperlanins A and B, Two Highly Rearranged Meroterpenoids from Hypericum lancasteri
Authors: You Jin‐Qiu , Jin Yun‐Qi , Li Meng‐Yu , Zhang Bo‐Chao , Sun Xin‐Yu , Ding Chun‐Yong , Li Jing‐Ya , Hou Ai‐Jun 
Published: May 2024

Comprehensive SummaryHyperlanins A (1) and B (2), two highly rearranged polycyclic polyprenylated acylphloroglucinol (PPAP)‐related meroterpenoids based on different new carbon skeletons, were isolated from Hypericum lancasteri. Compound 1 incorporates an unprecedented 5/6/7/5 ring system featuring a 3,13‐dioxatetracyclo[9.2.1.12,5.01,8]pentadecane core. Compound 2 possesses a unique compact 6/6/5/6/6/5/6 ring system with a caged tetracyclo[6.2.1.13,8.05,11]dodecane motif. Their structures were established by spectroscopic data, X‐ray diffraction, and computational approaches. Both compounds showed anti‐inflammatory activity in vitro. Compounds 1 and 2 could decrease the lipopolysaccharide (LPS)‐/nigericin‐induced IL‐1β release in THP‐1 cells. Both compounds also showed inhibition in hypoxia‐inducible factor‐1α (HIF‐1α) pathway luciferase reporter assay.
Nickel/Photoredox Dual Catalytic Chan‐Lam Coupling of Aryl Azides and Arylboric Acids
Authors: Ge Xia , Ji Haojie , Lu Hongjian 
Published: May 2024

Comprehensive SummaryUnsymmetrical diarylamines are crucial components in many pharmaceuticals and functional materials. In this study, we introduce an efficient Chan‐Lam cross‐coupling method that utilizes phenylboronic acids and aryl azides as coupling agents in a redox‐neutral environment, enabled by a synergistic nickel/photoredox catalytic system. This approach leverages a proton‐coupled electron transfer mechanism to bypass the typical nitrene pathway associated with aryl azides, which is prone to intramolecular rearrangement, C—H amination, and reductive hydrogenation. Notably, our method exhibits broad compatibility with a variety of functional groups, including those derived from pharmaceuticals, demonstrating its versatile potential in organic synthesis and drug modification.
Experimental and Theoretical Predictors for Redox Potentials of Bispyridinylidene Electron Donors
Authors: Khor Chun Keat , Calhoun Larry A. , Neville John J. , Dyker C. Adam 
Published: May 2024

AbstractBispyridinylidenes are neutral organic molecules capable of two‐electron oxidation at a range of redox potentials that are widely tunable by choice of substituent, making them attractive as homogeneous organic reductants and active materials in redox flow batteries. In an effort to readily predict the redox potentials of this important class of compounds, we have developed correlations between the experimental redox potentials and both experimental and theoretical predictors. On the experimental side, we show that multinuclear NMR chemical shifts of related pyridinium ions correlate well with the redox potentials of bispyridinylidenes, with R2 and standard errors (S) reaching 0.9810 and 0.048 V, respectively, when the 13C (N‐CH3) and 1H (ortho) chemical shifts are used together. Theoretical studies of the bispyridinylidenes and their doubly oxidized bipyridinium ions gave a range of predictively valuable equations at various levels of computational cost. This ranged from a simple model using only the EHOMO of the bispyridinylidenes (R2=0.9689; S=0.060 V), to a more computationally intensive model which include solvation effects for both redox states which gave the highest predictive value for all methods (R2=0.9958; S=0.022 V). This work will guide further studies of this important class of molecules.
Predictable local adaptation in butterfly photoperiodism but not thermal performance along a latitudinal cline
Authors: Siemers Isabelle , von Schmalensee Loke , Ziesemer Sabine , Gotthard Karl , Lehmann Philipp 
Published: May 2024

AbstractIn seasonal environments, organisms must synchronize their life cycles to conditions favorable for growth and reproduction. Because season length varies geographically, local adaptation should arise in traits that regulate phenological responses. Geographic photoperiodism clines are well known, but comparable studies on thermal performance are equivocal and often overlook nonlinear responses. Therefore, we examined local adaptation in plastic responses to both photoperiod and temperature along a 752‐km latitudinal cline, by comparing four Swedish populations of the butterflyPieris napi. Using a common garden design, we estimated (1) photoperiod response curves for diapause induction and (2) thermal performance curves for development and growth rates. We show that differences in photoperiodism follow the expected geographical pattern, where diapause is induced at longer daylengths in northern populations (where growth seasons are short and summer days long). However, population differences in thermal performance curves were small and seemingly idiosyncratic, without clear clinal patterns. Photoperiodic responses appear to evolve more readily than thermal responses, highlighting photoperiodism as a key driver of local life cycle synchronization.
Predation of cougar kittens following the aggregation of American black bears
Authors: Bianco Marcus D. , Ruprecht Joel , Clark Darren A. , Forrester Tavis , Levi Taal 
Published: May 2024

AbstractThe prevalence, intensity, or outcome of interference competition and interspecific killing between predominantly solitary species operating on large spatial scales is challenging to document or test. Here, we present a detailed account of inter‐ and intraspecific interactions from contemporaneous GPS location data and in‐field investigation. In June 2018, a GPS‐collared female cougar (Puma concolor) maintained strong site fidelity for a period of 19 days, indicative of parturition behavior and establishment of a nursery site. In early July 2018, three GPS‐collared black bears (Ursus americanus) arrived at the nursery site, after which the female cougar abandoned the site. Site investigation showed that one or more bears predated an unknown number of cougar kittens. The evidence supports ecological theory suggesting that body size, mass, or group number is an important predictor of outcome. Our observation provides an example of bears potentially making risk–reward trade‐offs by eliminating a potential competitor that at the same time provisions carrion as critical food resources. These real‐time inter‐ and intraspecies competitive interactions as documented using GPS collars allow for greater insight into individual fitness and community‐level effects.
Translocation in a fragmented river provides demographic benefits for imperiled fishes
Authors: Pennock Casey A. , Healy Brian D. , Bogaard Matthew R. , McKinstry Mark C. , Gido Keith B. , Cathcart C. Nathan , Hines Brian 
Published: May 2024

AbstractFragmentation isolates individuals and restricts access to valuable habitat with severe consequences for populations, such as reduced gene flow, disruption of recolonization dynamics, reduced resiliency to disturbance, and changes in aquatic community structure. Translocations to mitigate the effects of fragmentation and habitat loss are common, but few are rigorously evaluated, particularly for fishes. Over six years, we translocated 1215 individuals of four species of imperiled fish isolated below a barrier on the San Juan River, Utah, USA, that restricts access to upstream habitat. We used re‐encounter data (both passive integrated transponder tag and telemetry detections and physical recaptures) collected between 2016 and 2023, to inform a spatially explicit multistate mark–recapture model that estimated survival and transition probabilities of translocated and non‐translocated individuals, both below and above the barrier. Individuals of all four species moved large (>200 km) distances upstream following translocation, with the maximum upstream encounter distance varying by species. Results from the multistate mark–recapture model suggested translocated fish survived at a higher rate compared with non‐translocated fish below the barrier for three of the four species. Above the barrier, translocated individuals survived at similar rates as non‐translocated fish for bluehead sucker (Catostomus discobolus) and flannelmouth sucker (Catostomus latipinnis), while survival rates of translocated endangered Colorado pikeminnow (Ptychocheilus lucius; mean, 95% CI: 0.75, 0.55–0.88) and endangered razorback sucker (Xyrauchen texanus; 0.86, 0.75–0.92) were higher relative to non‐translocated individuals (Colorado pikeminnow: 0.52, 0.51–0.54; razorback sucker: 0.75, 0.74–0.75). Transition probabilities from above the barrier to below the barrier were generally low for three of the four species (all upper 95% CI ≤ 0.23), but they were substantially higher for razorback sucker. Our results suggest translocation to mitigate fragmentation and habitat loss can have demographic benefits for large‐river fish species by allowing movements necessary to complete their life history in heterogeneous riverscapes. Further, given the costs or delays in providing engineered fish passage structures or in achieving dam removal, we suggest translocations may provide an alternative conservation strategy in fragmented river systems.
Environmental DNA metabarcoding reliably recovers arthropod interactions which are frequently observed by video recordings of flowers
Authors: Stothut Manuel , Kühne Damaris , Ströbele Vanessa , Mahla Lisa , Künzel Sven , Krehenwinkel Henrik 
Published: May 2024

AbstractEnvironmental DNA (eDNA) metabarcoding promises to be a cost‐ and time‐efficient monitoring tool to detect interactions of arthropods with plants. However, observation‐based verification of the eDNA‐derived data is still required to confirm the reliability of those detections, i.e., to verify whether the arthropods have previously interacted with the plant. Here, we conducted a comparative analysis of the performance of eDNA metabarcoding and video camera observations to detect arthropod communities associated with sunflowers (Helianthus annuus, L.). We compared the taxonomic composition, interaction type, and diversity by testing for an effect of arthropod interaction time and occupancy on successful taxon recovery by eDNA. We also tested if prewashing of the flowers successfully removed eDNA deposition from before the video camera recording, thus enabling a reset of the community for standardized monitoring. We find that eDNA and video camera observations recovered distinct communities, with about a quarter of the arthropod families overlapping. However, the overlapping taxa comprised ~90% of the interactions observed by the video camera. Interestingly, eDNA metabarcoding recovered more unique families than the video cameras, but approximately two‐thirds of those unique observations were of rare species. The eDNA‐derived families were biased toward plant sap‐suckers, showing that such species may deposit more eDNA than, for example, transient pollinators. We also find that prewashing of the flower heads did not suffice to remove all eDNA traces, suggesting that eDNA on plants may be more temporally stable than previously thought. Our work highlights the great potential of eDNA as a tool to detect plant‐arthropod interactions, particularly for specialized and frequently interacting taxa.
One‐pot hydrothermal biochar obtained from malt bagasse waste as an electrode‐modifying material towards the stripping voltammetric sensing of lead
Authors: Dias da Silva Alexsandra , Silva Aline Aparecida dos Santos , da Silva Renê Chagas , Moreira Renata Pereira Lopes , Silva Tiago Almeida 
Published: May 2024

AbstractPb2+ ions are highly toxic to living beings because they tend to bioaccumulate in the body. For this reason, the development of simpler, low‐cost, and easy‐to‐operate techniques that can detect and quantify low concentrations of metal ions would help to identify contaminating media and improve public health. This work proposes a Pb2+ voltammetric sensor based on a carbon paste electrode modified with hydrothermal biochar (hydrochar, HC) obtained from malt bagasse waste (HC/CPE). The obtained hydrochar was characterized by zero‐charge point, FT‐IR, XRD and thermogravimetry. The differential pulse adsorptive anodic stripping voltammetry (DPAdASV) technique was used to perform the Pb2+ determination. After optimizing important parameters for detecting Pb2+ ions and the parameters of the voltammetric technique employed, a linear response range of 0.50 to 7.06 μmol L−1 with a limit of detection (LOD) and limit of quantification (LOQ) of 55.0 and 181.5 nmol L−1 were achieved, respectively. The developed voltammetric procedure was applied towards the Pb2+ determination at tap water and river water samples, with excellent recoveries (ranging of 91.19 to 109.22 %), proving that the HC‐based electrode has great potential for detecting Pb2+ ions. Hydrothermal carbonization allowed the biomass to be converted into functionalized hydrochar, eliminating the need for subsequent functionalization/activation steps for use as a Pb2+ adsorbing material on the electrodic surface. The proposed sensor also proved to be easy to assemble and environmentally friendly by using biomass waste as the carbon material. Thus, the proposed sensor adds to the literature the possibility of simple and easy detection of metal ions with a waste reuse bias.
What controls river widening? Comparing large and extreme flood events
Authors: Davidson Sarah L. , Marin‐Esteve Blanca , Eaton Brett 
Published: May 2024

AbstractExtreme (i.e., centennial‐scale) floods are by definition rare and can therefore be difficult to study. As a result, case studies of response to extreme floods can provide unique insights. On 15 November 2021, the Nicola River in British Columbia, Canada, experienced a 200‐year flood that increased the average width of the Nicola River by more than 50% (35 m), leaving the only highway in the region impassable for nearly 12 months. This research assesses the spatial variability of erosion along a 71‐km‐long segment of the Nicola River during a period with a large flood (2015–2018) and a second period containing the extreme flood in 2021 (2018–2021). We use a random forest statistical analysis to explore the most important valley and channel characteristics affecting relative widening during both periods. Unit stream power, gradient and valley confinement were the primary determinants of erosion during the extreme flood, whereas vegetation cover, channel pattern and surficial material were less important. Erosion during the large flood event was not related to these variables, with channel pattern providing a better indication of widening potential. As the Nicola River is flanked by erodible glacial deposits, this work provides important insight into river response in the paraglacial environments that are common throughout much of Canada and the northern United States, as well as Europe and Asia, but less intensely studied. In these settings, the geomorphic response to large floods may not be representative of the potential erosion (and infrastructure impacts) that can occur during extreme events, which destabilize glacial terraces in confined reaches. Historical observations should therefore be used with caution in paraglacial settings as extreme events may not be captured in available data, creating a perception of stability in confined reaches that may have the potential to erode dramatically during extreme events.