bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dissecting the Role of the Sergeants in Supramolecular Helical Catalysts: From Chain Capping to Intercalation
Authors: Martínez‐Aguirre Mayte A. , Li Yan , Vanthuyne Nicolas , Bouteiller Laurent , Raynal Matthieu 
Published: November 2020

AbstractControlling the properties of supramolecular assemblies requires unveiling the specific interactions between their components. In the present work, the catalytic properties and structure of co‐assemblies composed of a benzene‐1,3,5‐tricarboxamide (BTA) ligand coordinated to copper (the soldier) and seven enantiopure BTAs (the sergeants) have been determined. Whatever the sergeant, the enantioselectivity of the reaction is directly proportional to the optical purity of the supramolecular helices. More strikingly, the role played by the sergeant in the co‐assembly process differs significantly: from almost pure intercalator (when it is incorporated in the stacks of the soldier and generates long homochiral helices) to pure chain capper (when it leads to the formation of partly helically biased and short assemblies). The former situation leads to optimal enantioselectivity for the catalytic system under study (58 % ee) while the latter situation leads to very low selectivity (8 % ee). The successful rationalization of this high and unexpected difference is crucial for the development of more efficient catalysts and more elaborate supramolecular systems.
Carbazole‐Based DABNA Analogues as Highly Efficient Thermally Activated Delayed Fluorescence Materials for Narrowband Organic Light‐Emitting Diodes
Authors: Oda Susumu , Kumano Wataru , Hama Toshiki , Kawasumi Ryosuke , Yoshiura Kazuki , Hatakeyama Takuji 
Published: November 2020

AbstractCarbazole‐based DABNA analogues (CzDABNAs) were synthesized from triarylamine by regioselective one‐shot single and double borylation. The reaction proceeded selectively at the ortho position of the carbazolyl group, where the highest occupied molecular orbital is mainly localized owing to the difference in the electron‐donating abilities of the diarylamino and carbazolyl groups. The facile and scalable method enabled synthesis of CzDABNAs, exhibiting narrowband thermally activated delayed fluorescence with emission spectra ranging from deep blue to green. The organic light‐emitting diode devices employing these products as emitters exhibited deep‐blue, sky‐blue, and green emission with high external quantum efficiencies of 19.5, 21.8, and 26.7 %, respectively.
Optimization of off‐bottom spat collectors for restoration and production of the European flat oyster (Ostrea edulis) in Dutch coastal waters
Authors: van den Brink Anneke M. , Maathuis Margot A.M. , Kamermans Pauline 
Published: November 2020

Abstract

Efficient spat collection is essential to both the successful restoration and cultivation of the European flat oyster (Ostrea edulis).
The results of four different experiments investigating larval abundance, and the use of seven different types of suspended spat collectors in seven locations in the SW Netherlands were compared. These different types included Chinese hats, Vexar mesh, PVC tubes, and four types of bivalve shells.
Larval abundance, and timing of peaks in abundance for both O. edulis and the non‐indigenous Pacific oyster (Crassostrea gigas) varied between locations and years.
The most successful spat collectors were sacks of bivalve shells.
In general, most spat were observed on collectors deployed 1–2 weeks after the peak in larval abundance was detected.
Fouling was heavy and may have prevented larval settlement on collectors deployed too early. Suspended sacks of bivalve shells show great promise as O. edulis spat collectors intended for reef restoration purposes but may need further development for cultivation application.
Comparison of traditional and environmental DNA survey methods for detecting rare and abundant freshwater fish
Authors: Piggott Maxine P. , Banks Samuel C. , Broadhurst Ben T. , Fulton Christopher J. , Lintermans Mark 
Published: November 2020

Abstract

Detecting rare species is often a necessity for conservation and management, yet challenging for many field survey methods. Environmental DNA (eDNA) is a highly promising solution that has been shown to outperform many established survey methods.
Macquarie perch (Macquaria australasica) is an endangered native species that has declined significantly in range and abundance. Detection of M. australasica was compared with an abundant alien fish species (Oncorhynchus mykiss) using eDNA and three conventional survey methods: gill nets, electrofishing and fyke nets.
eDNA occupancy estimates for both fish species were compared using four different models to investigate what effect these differences have on false positives and false negatives for the rare and common fish species. These models used unadjusted eDNA detections in water samples, eDNA detections that have been screened using a limit of detection method to remove potential false positives, eDNA data supplemented with a second survey method, or eDNA data augmented with sequencing of positive polymerase chain reaction replicates.
eDNA surveying as a single detection method was found to be more efficient and sensitive compared with each capture method separately and combined. Occupancy estimates for the common and rare species did not vary significantly between the four site occupancy‐detection models, suggesting that supplementary data may not have as much effect on occupancy estimates compared with other approaches such as temporal or spatial sampling.
We conclude that eDNA outperforms the three established survey methods for both a rare and common freshwater fish species. Although there was no significant effect of augmenting eDNA survey methods with other survey data, additional data may improve confidence in detection, and provide confirmatory evidence for unexpected or new detections of a species.
Phage lysis‐lysogeny switches and programmed cell death: Danse macabre
Authors: Benler Sean , Koonin Eugene V. 
Published: November 2020

AbstractExploration of immune systems in prokaryotes, such as restriction‐modification or CRISPR‐Cas, shows that both innate and adaptive systems possess programmed cell death (PCD) potential. The key outstanding question is how the immune systems sense and “predict” infection outcomes to “decide” whether to fight the pathogen or induce PCD. There is a striking parallel between this life‐or‐death decision faced by the cell and the decision by temperate viruses to protect or kill their hosts, epitomized by the lysis‐lysogeny switch of bacteriophage Lambda. Immune systems and temperate phages sense the same molecular inputs, primarily, DNA damage, that determine whether the cell lives or dies. Because temperate (pro)phages are themselves components of prokaryotic genomes, their shared “interests” with the hosts result in coregulation of the lysis‐lysogeny switch and immune systems that jointly provide the cell with the decision machinery to probe and predict infection outcomes, answering the life‐or‐death question.
Single‐cell transcriptome analyses reveal heterogeneity in suspension cultures and clonal markers of CHO‐K1 cells
Authors: Ogata Norichika , Nishimura Akio , Matsuda Tomoko , Kubota Michi , Omasa Takeshi 
Published: November 2020

AbstractCell‐to‐cell variability in cell populations arises from a combination of intrinsic factors and extrinsic factors related to the milieu. However, the heterogeneity of high cell density suspension cultures for therapeutic protein production remains unknown. Here, we illustrate the increasing heterogeneity in the cellular transcriptome of serum‐free adapted CHO K1 cells during high cell density suspension culture over time without concomitant changes in the genomic sequence. Cell cycle‐dependent subpopulations and cell clusters, which typically appear in other single‐cell transcriptome analyses, were not found in these suspension cultures. Our results indicate that cell division changes the intracellular microenvironment and leads to cell cycle‐dependent heterogeneity. Whole mitochondrial single‐cell genome sequencing showed cell‐to‐cell mitochondrial genome variation and heteroplasmy within cells. The mitochondrial genome sequencing method developed here is potentially useful for the validation of cell clonality. The culture time‐dependent increase in cellular heterogeneity observed in this study did not show any attenuation in this increasing heterogeneity. Future advances in bioengineering such as culture upscaling, prolonged culturing, and complex culture systems will be confronted with the need to assess and control cellular heterogeneity, and the method described here may prove useful for this purpose.
Simplified Monopalmitoyl Toll‐like Receptor 2 Ligand Mini‐UPam for Self‐Adjuvanting Neoantigen‐Based Synthetic Cancer Vaccines
Authors: van den Ende Thomas C. , Heuts Jeroen M. M. , Gential Geoffroy P. P. , Visser Marten , van de Graaff Michel J. , Ho Nataschja I. , Jiskoot Wim , Valentijn A. Rob P. M. , Meeuwenoord Nico J. , Overkleeft Herman S. , Codée Jeroen D. C. , van der Burg Sjoerd H. , Verdegaal Els M. E. , van der Marel Gijsbert A. , Ossendorp Ferry , Filippov Dmitri V. 
Published: November 2020

AbstractSynthetic vaccines, based on antigenic peptides that comprise MHC−I and MHC‐II T‐cell epitopes expressed by tumors, show great promise for the immunotherapy of cancer. For optimal immunogenicity, the synthetic peptides (SPs) should be adjuvanted with suitable immunostimulatory additives. Previously, we have shown that improved immunogenicity in vivo is obtained with vaccine modalities in which an SP is covalently connected to an adjuvanting moiety, typically a ligand to Toll‐like receptor 2 (TLR2). SPs were covalently attached to UPam, which is a derivative of the classic TLR2 ligand Pam3CysSK4. A disadvantage of the triply palmitoylated UPam is its high lipophilicity, which precludes universal adoption of this adjuvant for covalent modification of various antigenic peptides as it renders the synthetic vaccine insoluble in several cases. Here, we report a novel conjugatable TLR2 ligand, mini‐UPam, which contains only one palmitoyl chain, rather than three, and therefore has less impact on the solubility and other physicochemical properties of a synthetic peptide. In this study, we used SPs that contain the clinically relevant neoepitopes identified in a melanoma patient who completely recovered after T‐cell therapy. Homogeneous mini‐UPam‐SP conjugates have been prepared in good yields by stepwise solid‐phase synthesis that employed a mini‐UPam building block pre‐prepared in solution and the standard set of Fmoc‐amino acids. The immunogenicity of the novel mini‐UPam‐SP conjugates was demonstrated by using the cancer patient's T‐cells.
n‐Butyllithium Catalyzed Hydroboration of Nitriles and Carbodiimides
Authors: Yan Ben , He Xing , Ni Congjian , Yang Zhi , Ma Xiaoli 
Published: November 2020

AbstractHighly efficient and selective hydroboration of nitriles and carbodiimides with pinacolborane (HBpin) is achieved by using the simple and convenientn‐BuLi as a catalyst. Solvent‐free and good functional group tolerance under mild conditions have been achieved. A possible mechanistic pathway of then‐BuLi catalyzed hydroboration of nitriles with HBpin is proposed.
Electrochemical Determination of the Steroid Tibolone and Its Metabolites in Saliva Samples
Authors: Silva Weberson P. , Rocha Raquel G. , Felisbino John K. R. P. , Sousa Raquel M. F. , Munoz Rodrigo A. A. , Richter Eduardo M. 
Published: November 2020

AbstractTibolone (TIB) is a synthetic steroid banned by the World Anti‐Doping Agency (WADA) due to its similar properties to estrogen and progesterone. In this work, a simple and low‐cost electrochemical method for the determination of TIB and its metabolites (3‐α hydroxytibolone and 3‐β hydroxytibolone) in authentic human saliva is reported. Square‐wave voltammetry (SWV) with an unmodified boron‐doped diamond (BDD) electrode and phosphate buffer 0.1 mol L−1 were selected as the electrochemical technique, working electrode, and supporting electrolyte, respectively. Analytical characteristics of the proposed method include good repeatability (RSD <2.4 %), wide linear range (1 to 110 μmol L−1; r=0.999) and low detection limit (0.3 μmol L−1). Average recovery values (104±3 % for TIB and 98±5 % for the metabolites) for direct analysis of spiked saliva samples (only diluted in supporting electrolyte) indicate that no significant matrix interference was observed. The proposed method was also efficient for the determination of TIB in pharmaceutical samples (statistically similar results to those obtained by HPLC).
Electrochemical Activity of Cytochrome P450 1A2: The Relevance of O2 Control and the Natural Electron Donor
Authors: Silveira Célia M. , Rodrigues Patrícia R. , Ghach Wissam , Pereira Sofia A. , Esteves Francisco , Kranendonk Michel , Etienne Mathieu , Almeida M. Gabriela 
Published: November 2020

AbstractThe direct electrochemical response of membrane‐bound human cytochrome P450 1A2 (CYP1A2) was studied on pyrolytic graphite electrodes, while encapsulated in a sol‐gel matrix. The enzymatic reduction of O2 was evaluated in the presence and absence of its electron donor partner, cytochrome P450 oxidoreductase (CPR). When used without CPR, CYP1A2 was shown to be highly sensitive to O2 even in the presence of residual amounts. Under aerobic conditions (air‐saturated solutions), the catalytic signal attributed to the reaction with O2 was lost, suggesting the enzyme was inactivated. In contrast, the CYP1A2/CPR complex retained O2 reductase activity with high O2 concentration in solution. The results demonstrated a crucial role of CPR in stabilizing the immobilized CYP1A2 enzyme and in the preservation of O2 electrocatalysis, when using this electrochemical set‐up. Though the enzyme's monooxygenase activity towards caffeine was not detected, this study highlights the complexity of coupling CYP1A2 reduction currents with substrate turnover, owing to the simultaneous electrochemical measurement of the O2 reduction reaction.
Use of florpyrauxifen‐benzyl in non‐flooded rice production systems
Authors: Wright Hannah E. , Norsworthy Jason K. , Roberts Trenton L. , Scott Robert C. , Hardke Jarrod T. , Gbur Edward E. 
Published: November 2020

AbstractThe lack of a flood on rice (Oryza sativa) levees and in furrow‐irrigated rice creates a favorable environment for terrestrial weeds like Palmer amaranth (Amaranthus palmeri S. Wats) to emerge and quickly overtake the crop for a longer portion of the year than in flooded rice culture. Florpyrauxifen‐benzyl is a new auxin herbicide labeled for use in rice that has activity on both grasses and broadleaf weeds, as well as certain sedges. Field experiments were conducted to determine the efficacy of florpyrauxifen‐benzyl in a non‐flooded environment. Experiments were conducted in 2017 and 2018 at the Lon Mann Cotton Research Station in Marianna, AR and the Pine Tree Research Station near Colt, AR to evaluate florpyrauxifen‐benzyl within a herbicide‐based weed control program in furrow‐irrigated rice. Programs evaluated included two preemergence herbicide combinations, four mid‐postemergence combinations, and a late‐postemergence application versus none. Another experiment was conducted at the Pine Tree Research Station in 2017 and 2018 to compare florpyrauxifen‐benzyl with 2,4‐D in different herbicide mixtures for weed control on rice levees. Treatments consisted of several commonly used rice herbicides applied alone and in a mixture with florpyrauxifen‐benzyl and with 2,4‐D. In the furrow‐irrigated rice experiment, programs containing florpyrauxifen‐benzyl in the mid‐postemergence application resulted in higher levels of late‐season Palmer amaranth control (96–98%) compared to the standard mid‐postemergence treatment (85%). Additionally, programs that included a late‐postemergence herbicide application controlled Palmer amaranth (98%) compared to programs where no late‐postemergence herbicide was applied (91%). In the levee experiment, mixtures where florpyrauxifen‐benzyl was used offered comparable control of Palmer amaranth to mixtures containing 2,4‐D. Mixtures where 2,4‐D or florpyrauxifen‐benzyl were used controlled Palmer amaranth better than the individual herbicide applied alone. Results from these experiments indicate florpyrauxifen‐benzyl will sufficiently control Palmer amaranth in a non‐flooded environment, providing a good alternative herbicide and viable weed control option in furrow‐irrigated rice and on rice levees.
A novel fuzzy clustering algorithm based on rough set and inhibitive factor
Authors: Tang Leiyu , Wang Chenxi , Wang Shudong , Dong Guoliang , Fan Jiancong 
Published: November 2020

SummaryAs an important data analysis method, rough set theory can be used to analyze data with uncertainties. Rough set is able to acquire knowledge by the indistinguishable relationship among data objects without any prior knowledge. Rough set theory provides a new theoretical means for solving soft computing problems and has a wide application space in data mining. Meanwhile, the fuzzy C‐means clustering algorithm is sensitive to noisy points and has low convergence speed. In order to deal with the above problems, a novel fuzzy clustering algorithm based on rough set and inhibitive factor is proposed. According to the related concepts of rough set theory, the membership model of fuzzy C‐means algorithm is redefined. Besides, an inhibitive factor is set to improve the convergence speed of the algorithm under the premise of guaranteeing the clustering effect.
Sensitive Electrochemical Detection of Pb(II) and H2O2 via a Dual‐functional Sn‐doped Defective Bi2S3 Microspheres
Authors: Fu Yanqiu , Li Jinrui , Jin Wei , Liu Zhonggang 
Published: November 2020

AbstractIn this work, a dual‐functional electrochemical sensor has been proposed based on Sn‐doped defective Bi2S3 (TDDB) microspheres, which exhibited the excellent electrochemical performance on Pb(II) and H2O2 detection. The TDDB offered a satisfied detection limit of 8.0 nM towards Pb(II) with a sensitivity of 96.7 μA ⋅ μM−1. As a H2O2 sensor, a high sensitivity of 3540 μA mM−1 cm−2 was obtained in a linear range from 0.45 mM to 10 mM with a detection limit of 10 nM. Moreover, the electrochemical detection of Pb(II) in Taihu Lake and H2O2 in human serum was achieved with high reliability and good recovery.
A novel hydrogel sheet prevents postoperative pancreatic fistula in a rat model
Authors: Kemmochi Akira , Tamura Takafumi , Shimizu Yoshio , Owada Yohei , Ozawa Yusuke , Hisakura Katsuji , Oda Tatsuya , Kawano Yayoi , Hanawa Takehisa , Ohkohchi Nobuhiro 
Published: November 2020

AbstractAimTo evaluate the efficacy of a novel hydrogel sheet in preventing postoperative pancreatic fistula (POPF).BackgroundPostoperative pancreatic fistula is a life‐threatening complication. As no study has reported the use of hydrogel sheets in preventing POPF, their effectiveness for that purpose remains unclear.MethodsA novel hydrogel sheet made of polyvinyl alcohol (PVA) was prepared by the freeze‐thaw method. The pancreatic ducts and surrounding pancreatic parenchyma of rats were transected to induce a pancreatic fistula. Next, the sheet was attached to the transection site. Ascitic fluid amylase and lipase concentrations were measured. Neoveil®, a nonwoven polyglycolic acid (PGA) felt, is already clinically used as an absorbable reinforcing material at pancreatic transection sites. Neoveil® was used for comparison, as was VIEWGEL®, which is marketed as a wound dressing.ResultsThe hydrogel sheet remained in place 48 hours postoperatively. The ascitic amylase concentrations in the control, VIEWGEL®‐treated, Neoveil®‐treated, and hydrogel‐treated rats, respectively, were 4992.4 ± 5355.7, 1068.4 ± 269.1, 730.2 ± 425.2, and 303.1 ± 240.1 IU/L; the ascitic lipase concentrations were 2279.8 ± 3395.2, 169.5 ± 100.6, 90.4 ± 71.0, and 86.8 ± 59.8 IU/L. The ascitic amylase and lipase levels were significantly lower in the hydrogel group than in the other groups (P < .05).ConclusionsThis novel hydrogel sheet effectively prevents pancreatic fistulas and has promising clinical application potential.
Microserendipity in the Creative Process
Authors: Ross Wendy , Vallée‐Tourangeau Frédéric 
Published: November 2020

AbstractQualitative research on creativity often highlights the role of accidents in creative process, but there is little research that takes these as its main topic. Perhaps because a model that relies on accidents undermines the meaningfulness of creativity; perhaps because the phenomenon itself is too complex to underwrite an entire research program. This paper suggests the framework of serendipity to better understand the interaction between a person and chance occurrences. Serendipity is a fortuitous accident, the enactment of environmental luck by a prepared mind. Current research on serendipity proceeds from a mainly retrospective position, centring the experience of the person. This creates a serendipitous narrative without necessarily telling us more about the moment itself. It is thus harder to consider the role of accidental moments and the nature of their contribution to the creative process. We argue that these moments, viewed outside of the person’s narrative account, are worthy of study and offer some suggestions for how that might occur. We use the term “microserendipity” to designate moments which arise from distributed creative agency. We suggest we can support current research in both creativity and serendipity by undertaking detailed analysis of observational data to scaffold understanding of these complex phenomena.
Effects of superfine grinding using ball‐milling on the physical properties, chemical composition, and antioxidant properties of Quercus salicina (Blume) leaf powders
Authors: Hong Seong‐Jin , Das Protiva Rani , Eun Jong‐Bang 
Published: November 2020

AbstractBACKGROUNDQuercus salicina (Blume) leaves are traditionally used as folk medicine in some Asian countries. The aim of this study was to evaluate the effects of ball milling for different periods (0, 6, 12, 18, and 24 h) on the physicochemical properties of superfine Quercus salicina (Blume) leaf (QSL) powders.RESULTSThe particle sizes, water‐holding capacity, angle of repose, and redness of the superfine QSL powder decreased with increasing ball‐milling times, whereas the water solubility index, bulk density, tapped density, brightness, and yellowness were found to increase. Significantly higher (P > 0.05) total phenolic and flavonoid contents, and antioxidant activities, were observed for the superfine QSL powders obtained after 24 h ball‐milling time. A total of 12 phenolic compounds in free and cell‐wall‐bound forms were quantified in the superfine QSL powder. Free phenolics such as protocatechuic acid, caffeic acid, rutin, and p‐coumaric acid were increased and all cell‐wall‐bound phenolics were decreased with increasing ball‐milling times. The antioxidant activity of the free phenolics increased with increasing ball‐milling times, and the cell‐wall‐bound forms decreased.CONCLUSIONSuperfine grinding by ball milling for 24 h can thus be used to produce superfine QSL powder with higher free phenolic metabolite content and antioxidant activity, and improved water solubility index, color, bulk, and tapped densities. This study will be useful for the food / nutraceutical / pharmaceutical industries in the manufacturing of active food ingredients or value‐added products using QSL powders. © 2020 Society of Chemical Industry