bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analyzing bacterial community in pit mud of Yibin Baijiu in China using high throughput sequencing
Authors: Chen Li , Li Yuzhu , Jin Lei , He Li , Ao Xiaolin , Liu Shuliang , Yang Yong , Liu Aiping , Chen Shujuan , Zou Likou 
Published: May 2020

“Yibin Baijiu” (YB) is a special Chinese strong-aroma Baijiu (CSAB) that originated in Yibin, a city in western China. YB is fermented in cellars lined with pit mud (PM), the microbiota in which may affect YB quality. In this study, high throughput sequencing of the 16S rRNA gene was used to demonstrate the bacterial community structure and diversity in PM of YB. In addition, the physicochemical characteristics of PM were also analyzed, including moisture content, pH, and available phosphorous, ammonia nitrogen, and humic acid levels. Results showed that Firmicutes was the dominant phylum in all PM samples with abundance > 70.0%, followed by Euryarchaeota (11.3%), Bacteroidetes (6.5%), Synergistetes (3.0%), Actinobacteria (1.4%), and Proteobacteria (1.2%). Furthermore, 14 different genera with average relative abundance of > 1% were detected. The Chao1 and Shannon indexes did not vary significantly between the sub-layer and middle-layer PM (P > 0.05). However, Linear discriminant analysis Effect Size (LEfSe) analysis showed that the relative abundance of Lactobacillus in the sub-layer PM was significantly higher than in middle-layer PM. pH differed significantly (P < 0.05) between the two groups. Canonical correspondence analysis revealed that bacterial community in PM correlated significantly with available phosphorous content and pH. Our study provides basic data for further elucidating the diversity of microbiota in the PM of YB and the potential mechanism of Baijiu production.
Modeling EV Kinetics for Use in Early Cancer Detection
Authors: Ferguson Scott , Weissleder Ralph 
Published: May 2020

AbstractTumor‐derived extracellular vesicles (EVs) represent promising biomarkers for monitoring cancers. Technological advances have improved the ability to measure EV reliably in blood using protein, RNA, or lipid detection methods. However, it is less clear how efficacious current EV assays are for the early detection of small and thus curable tumors. Here, a mathematical model is developed to estimate key parameter values and future requirements for EV testing. Tumor volumes in mice correlate well with increases in total number of circulating EV allowing the researchers to calculate EV shed rates for four different published cancer models. Model extrapolations to human physiology show good agreement with published clinical data. Specifically, it is shown that current bulk EV detection systems are ≈104‐fold too insensitive to detect human cancers of ≈1 cm3. Conversely, it is predicted that emerging single EV methods will allow blood‐based detection of cancers of <1 mm3 in humans.
Palladium(II)‐Catalyzed Direct Access to Indeno[1,2‐c]isochromen‐5(11H)‐Ones via Intramolecular Oxypalladation‐Initiated Cascade Process
Authors: Karuppasamy Muthu , Vachan B. S. , Jandial Tanvi , Babiola Annes Sesuraj , Bhuvanesh Nattamai , Uma Maheswari C. , Sridharan Vellaisamy 
Published: May 2020

AbstractA palladium(II)‐catalyzed cascade approach was established for the synthesis of indeno[1,2‐c]isochromen‐5(11H)‐ones starting from 2‐alkynyl tert‐butyl benzoates bearing a pendant α,β‐unsaturated carbonyl moiety in high yields (up to 99%) under mild conditions. This strategy offered high atom and step economy by delivering isobutene as the only side product, and by generating two new bonds and two rings in a single synthetic operation. The mechanism of the cascade process was visualized comprising sequential intramolecular oxypalladation (6‐endo‐dig), intramolecular olefin insertion, and protonation steps.magnified image
Metformin Restores Tetracyclines Susceptibility against Multidrug Resistant Bacteria
Authors: Liu Yuan , Jia Yuqian , Yang Kangni , Li Ruichao , Xiao Xia , Zhu Kui , Wang Zhiqiang 
Published: May 2020

AbstractHighly persistent incidence of multidrug resistant (MDR) bacterial pathogens constitutes a global burden for public health. An alternative strategy to alleviate such a crisis is to identify promising compounds to restore antibiotics activity against MDR bacteria. It is reported that the antidiabetic drug metformin exhibits the potentiation effect on tetracycline antibiotics, particularly doxycycline and minocycline, against MDR S. aureus, E. faecalis, E. coli, and S. enteritidis. Mechanistic studies demonstrate that metformin promotes intracellular accumulation of doxycycline in tetracycline‐resistant E. coli. In addition, metformin boosts the immune response and alleviates the inflammatory responses in vitro. Last, metformin fully restores the activity of doxycycline in three animal infection models. Collectively, these results reveal the potential of metformin as a novel tetracyclines adjuvant to circumvent MDR bacterial pathogens and to improve the treatment outcome of recalcitrant infections.
Energetics and Energy Loss in 2D Ruddlesden–Popper Perovskite Solar Cells
Authors: Yang Jianming , Xiong Shaobing , Song Jingnan , Wu Hongbo , Zeng Yihan , Lu Linyang , Shen Kongchao , Hao Tianyu , Ma Zaifei , Liu Feng , Duan Chungang , Fahlman Mats , Bao Qinye 
Published: May 2020

Abstract2D Ruddlesden–Popper perovskites (RPPs) are emerging as potential challengers to their 3D counterpart due to superior stability and competitive efficiency. However, the fundamental questions on energetics of the 2D RPPs are not well understood. Here, the energetics at (PEA)2(MA)n−1PbnI3n+1/[6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM) interfaces with varying n values of 1, 3, 5, 40, and ∞ are systematically investigated. It is found that n–n junctions form at the 2D RPP interfaces (n = 3, 5, and 40), instead of p–n junctions in the pure 2D and 3D scenarios (n = 1 and ∞). The potential gradient across phenethylammonium iodide ligands that significantly decreases surface work function, promotes separation of the photogenerated charge carriers with electron transferring from perovskite crystal to ligand at the interface, reducing charge recombination, which contributes to the smallest energy loss and the highest open‐circuit voltage (Voc) in the perovskite solar cells (PSCs) based on the 2D RPP (n = 5)/PCBM. The mechanism is further verified by inserting a thin 2D RPP capping layer between pure 3D perovskite and PCBM in PSCs, causing the Voc to evidently increase by 94 mV. Capacitance–voltage measurements with Mott–Schottky analysis demonstrate that such Voc improvement is attributed to the enhanced potential at the interface.
Sustainable Engaged Accountable Learners
Authors: Gisondi Michael A. , Branzetti Jeremy , Hopson Laura R. , Regan Linda 
Published: May 2020

AbstractThe development of lifelong learners is among the most challenging goals for medical educators. The authors identify two important scholarly works that profoundly altered their understanding and approach to lifelong learning and curriculum design: L. Dee Fink’sTaxonomy of Significant Learningand Cutrer et al.’sMaster Adaptive Learnermodel. By applying these guides to their teaching and related research, three important characteristics of lifelong learning became evident: sustainability, engagement, and accountability. These are abbreviated “SEALs,” for sustainable engaged accountable learners. This paper defines these qualities as they relate to emergency medicine training, significant learning, and the development of adaptive expertise. Connections to Fink’s and Cutrer’s works are offered for each learner characteristic. Educational and psychological theories that support the SEALs model are paired with practical suggestions for educators to promote these desired qualities in their trainees. Relevant features of adult learning are highlighted, including self‐regulation, motivation, agency, and autonomy.
Determination and correlation of temperature and pH value dependent solubility of dl‐methionine
Authors: Chen Zhirong , Zhou Rongfan , Yin Hong , Yuan Shenfeng 
Published: May 2020

AbstractIn order to provide basic data for the crystallization of dl‐methionine and understand the thermodynamic properties of dissolution, the solubility of dl‐methionine in water was measured by gravimetric method from 294.05 to 347.05 K and the solubility at different pH values under temperature 302.95 to 342.05 K was determined by elemental analysis in this work. The experimental data show that the solubility of dl‐methionine increases with increasing temperature as well as more acidic or basic pH values. The van't Hoff equation, modified Apelblat equation, λh equation, Wilson model, NRTL model, and UNIQUAC model were used to correlate the solubility data versus temperature. The melting temperature, enthalpy of fusion, enthalpy and entropy of dissolution were estimated from solubility data and it shows that the expression of solubility by enthalpy and entropy of dissolution gives more reasonable estimation and Wilson model gives a better correlation for these thermodynamic properties.
Precision Molecular Threading/Dethreading
Authors: Groppi Jessica , Casimiro Lorenzo , Canton Martina , Corra Stefano , Jafari‐Nasab Mina , Tabacchi Gloria , Cavallo Luigi , Baroncini Massimo , Silvi Serena , Fois Ettore , Credi Alberto 
Published: May 2020

AbstractThe general principles guiding the design of molecular machines based on interlocked structures are well known. Nonetheless, the identification of suitable molecular components for a precise tuning of the energetic parameters that determine the mechanical link is still challenging. Indeed, what are the reasons of the “all‐or‐nothing” effect, which turns a molecular “speed‐bump” into a stopper in pseudorotaxane‐based architectures? Here we investigate the threading and dethreading processes for a representative class of molecular components, based on symmetric dibenzylammonium axles and dibenzo[24]crown‐8 ether, with a joint experimental–computational strategy. From the analysis of quantitative data and an atomistic insight, we derive simple rules correlating the kinetic behaviour with the substitution pattern, and provide rational guidelines for the design of modules to be integrated in molecular switches and motors with sophisticated dynamic features.
Direct Umpolung Morita–Baylis–Hillman like α‐Functionalization of Enones via Enolonium Species
Authors: Arava Shlomy , Santra Sourav K. , Pathe Gulab K. , Kapanaiah Raja , Szpilman Alex M. 
Published: May 2020

AbstractHerein we report on the umpolung of Morita–Baylis–Hillman type intermediates and application to the α‐functionalization of enone C−H bonds. This reaction gives direct access to α‐chloro‐enones, 1,2‐diketones and α‐tosyloxy‐enones. The latter are important intermediates for cross‐coupling reaction and, to the best of our knowledge, cannot be made in a single step from enones in any other way. The proposed mechanism is supported by spectroscopic studies. The key initial step involves conjugate attack of an amine (DABCO or pyridine), likely assisted by hypervalent iodine acting as a Lewis acid leading to formation of an electrophilic β‐ammonium‐enolonium species. Nucleophilic attack by acetate, tosylate, or chloride anion is followed by base induced elimination of the ammonium species to give the noted products. Hydrolysis of α‐acetoxy‐enones lead to formation of 1,2‐diketones. The α‐tosyl‐enones participate in Negishi coupling reactions under standard conditions.
DNA Nanolithography Enables a Highly Ordered Recognition Interface in a Microfluidic Chip for the Efficient Capture and Release of Circulating Tumor Cells
Authors: Zhang Jialu , Lin Bingqian , Wu Lingling , Huang Mengjiao , Li Xingrui , Zhang Huimin , Song Jia , Wang Wei , Zhao Gang , Song Yanling , Yang Chaoyong 
Published: May 2020

AbstractMicrofluidic chips with nano‐scale structures have shown great potential, but the fabrication and cost issues restrict their application. Herein, we propose a conceptually new “DNA nanolithography in a microfluidic chip” by using sub‐10 nm three‐dimensional DNA structures (TDNs) as frameworks with a pendant aptamer at the top vertex (ApTDN‐Chip). The nano‐scale framework ensures that the aptamer is in a highly ordered upright orientation, avoiding the undesired orientation or crowding effects caused by conventional microfluidic interface fabrication processes. Compared with a monovalent aptamer modified chip, the capture efficiency of ApTDN‐Chip was enhanced nearly 60 % due to the highly precise dimension and rigid framework of TDNs. In addition, the scaffolds make DNase I more accessible to the aptamer with up to 83 % release efficiency and 91 % cell viability, which is fully compatible with downstream molecular analysis. Overall, this strategy provides a novel perspective on engineering nano‐scaffolds to achieve a more ordered nano‐topography of microfluidic chips.
Complementing Pyridine‐2,6‐bis(oxazoline) with Cyclometalated N‐Heterocyclic Carbene for Asymmetric Ruthenium Catalysis
Authors: Li Long , Han Feng , Nie Xin , Hong Yubiao , Ivlev Sergei , Meggers Eric 
Published: May 2020

AbstractA strategy for expanding the utility of chiral pyridine‐2,6‐bis(oxazoline) (pybox) ligands for asymmetric transition metal catalysis is introduced by adding a bidentate ligand to modulate the electronic properties and asymmetric induction. Specifically, a ruthenium(II) pybox fragment is combined with a cyclometalated N‐heterocyclic carbene (NHC) ligand to generate catalysts for enantioselective transition metal nitrenoid chemistry, including ring contraction to chiral 2H‐azirines (up to 97 % ee with 2000 TON) and enantioselective C(sp3)−H aminations (up to 97 % ee with 50 TON).
Epoxy‐based composite adhesives with improved lap shear strengths at high temperatures for steel‐steel bonded joints
Authors: Chailee Orawan , Parnklang Tewarak , Mora Phattarin , Pothisiri Thanyawat , Jubsilp Chanchira , Rimdusit Sarawut 
Published: May 2020

AbstractHigh‐performance room temperature‐cure epoxy structural adhesives utilizing simplified formulation are developed. The developed structural adhesive consists of diglycidyl ether of bisphenol A (DGEBA) and novolac epoxy blend as a base resin, micrometer‐sized silica particles as a reinforcing filler, and triethylenetetramine as a curing agent. The developed ambient temperature‐cure epoxy structural adhesive with optimized formulation exhibits outstanding properties including high glass transition temperature of 95°C, high thermal stability with degradation temperature at 5% weight loss of 364°C, exceptionally high rubbery plateau modulus of 320 MPa, good flame‐retardant characteristics with limiting oxygen index of 40, and high single lap shear strength for single lap steel‐steel bonded joint of 548 MPa at the temperature of 80°C. The silica‐filled DGEBA/novolac epoxy composite adhesive is a potential candidate for applying as a structural adhesive for construction with long‐term durability.
A new approach to estimate the curing mode of thermosetting polymer films with regard to physical aging and slow chemical processes
Authors: Zhavoronok Elena S. , Senchikhin Ivan N. 
Published: May 2020

AbstractWe propose an original method to determine the temperature and time required for additional curing of physically aged partially cured glass‐shaped systems, based on the example of epoxy amine systems. The approach consists of the plotting of temperature–time–transformation (TTT) diagrams, supplemented with lines, which illustrate the shift in glass transition temperature (Tg) as a result of the processes of physical aging (enthalpy relaxation) and with isoconversion curves. Then we should determine Tg of partially cured and aged sample at a certain temperature. Having known this Tg value, the position of the isoconversion curve at a given point and Tg,∞ as well, we can determine the postcuring time at T = Tg,∞ + 5 K. Thus, the method provides information about the temperatures and the duration of these two consecutive steps. The TTT diagrams are based on experimental results obtained by differential scanning calorimetry in dynamic mode with preliminary heated samples in an external thermostat. The proposed approach based on epoxy amine systems allows the prediction of the optimal curing mode for thermosetting systems to provide the highest degree of cure. Our method is applicable to a wide range of thermosetting polymer systems that complete transition to a glassy state before full conversion is achieved.
Variation within laminae: Semi‐automated methods for quantifying leaf venation using phenoVein
Authors: Newsome Eastyn L. , Brock Grace L. , Lutz Jared , Baker Robert L. 
Published: May 2020

PremisePhysiological processes may vary within leaf laminae; however, the accompanying heterogeneity in leaf venation is rarely investigated because its quantification can be time consuming. Here we introduce accelerated protocols using existing software to increase sample throughput and ask whether laminae venation varies among three crop types and four subspecies of Brassica rapa.MethodsFAA (formaldehyde, glacial acetic acid, and ethanol)‐fixed samples were stored in ethanol. Without performing any additional clearing or staining, we tested two methods of image acquisition at three locations along the proximal‐distal axis of the laminae and estimated the patterns of venation using the program phenoVein. We developed and made available an R script to handle the phenoVein output and then analyzed our data using linear mixed‐effects models.ResultsBeyond fixation and storage, staining and clearing are not necessary to estimate leaf venation using phenoVein if the images are acquired using a stereomicroscope. All estimates of venation required some manual adjustment. We found a significant effect of location within the laminae for all aspects of venation.DiscussionBy removing the clearing and staining steps and utilizing the semi‐automated program phenoVein, we quickly and cheaply acquired leaf venation data. Venation may be an important target for crop breeding efforts, particularly if intralaminar variation correlates with variation in physiological processes, which remains an open question.
RETRACTED:Alpinumisoflavone triggers GSDME‐dependent pyroptosis in esophageal squamous cell carcinomas
Authors: Zhang Bin , Zhu Wen‐Yong , Tian Hui , Zhang Huan‐Rong 
Published: May 2020

AbstractEsophageal squamous cell carcinoma (ESCC) presents a common human malignancy in the digestive system. We aimed to explore the critical effects of alpinumisoflavone (AIF) on ESCC in vitro and in vivo. The cell counting kit‐8 assay was used to determine cell viability. Colony formation assay was employed to examine the effect of AIF on the long‐term growth of ESCC cells. Cell apoptosis was determined by flow cytometry and terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling assay. Cell morphologies were observed by light microscopy. The enzyme‐linked immunosorbent assay was performed to examine the lactate dehydrogenase release from AIF‐treated cells. Immunofluorescent labeling was utilized to examine AIF‐induced GSDME expression. Western blot was employed to determine the expression levels of the associated proteins. Immunohistochemistry was performed to determine the localization and expression of the associated proteins in mice tumor tissues. AIF inhibited ESCC cell viability and suppressed cell growth in a dose‐ and time‐dependent fashion. Results showed that AIF promoted apoptosis in ESCC cells. Meanwhile, our results also showed that AIF triggered pyroptotic cell death in ESCC, which was mediated by gasdermin E (GSDME) cleavage. In addition, our experiments provided experimental evidence that AIF‐induced GSDME cleavage was dependent on caspase‐3 activation. Moreover, the inhibition of GSDSE by knockdown was able to switch the form of cell death from pyroptosis to apoptosis. Furthermore, the results from the xenograft animal model also supported our findings in vitro that AIF was able to promote GSDME‐mediated pyroptotic cell death in ESCC. AIF inhibited ESCC growth in vitro and in vivo by triggering GSDME‐mediated pyroptotic cell death, which is dependent on caspase‐3 activation.
Histological, histochemical, and immunohistochemical studies of hippocampus in male New Zealand rabbits
Authors: Mazher Khaled M. , Hassan Randa M. 
Published: May 2020

AbstractThe present study aims to give detailed histomorphological features of the hippocampus of adult male New Zealand rabbits. Both histological and histochemical specimens were prepared to be examined microscopically by using a light microscope. The hippocampus appeared as C‐shaped hippocampal proper, dentate gyrus, and subiculum. The hippocampal proper subdivided along its length according to the density and size of its major constituent pyramidal cells into four distinct regions named Cornu Ammonis (CA1, CA2, CA3, and CA4). With the histochemical preparations, each of these regions consisted of five layers, stratum alveolus, stratum oriens, stratum pyramidale, stratum radiatum, and stratum lacunosum‐moleculare. The stratum pyramidale constituted the middle dark zone and contained the principal excitatory neurons and a few interneurons. Histochemically, the pyramidal neurons along all regions of the CA reacted positively to Grimelius silver impregnation, lead hematoxylin, Gomori's aldehyde fuchsin, aldehyde thionine, Gomori's chrome alum hematoxylin, and performic acid alcian blue stains. Immunohistochemically, the pyramidal neurons reacted positively to anti‐NSE antibodies. The dentate gyrus was formed of three distinct layers. The subiculum was formed of proper subiculum, presubiculum, and parasubiculum.
Immunohistochemical characterization of postnatal changes in cerebellar cortical cytoarchitectures in ferrets
Authors: Kamiya Shiori , Sawada Kazuhiko 
Published: May 2020

AbstractWe immunohistochemically characterized postnatal changes in cerebellar cortical cytoarchitectures in ferrets using markers for cerebellar cortical neurons and glial cells. Although 10 lobules of the vermis were already observed on postnatal day (PD) 4, Purkinje cells were still arrayed into two to three layers. Purkinje cells were aligned in a monolayer by PD 10 and formed mature shapes on PD 42 by developing their dendritic arbors. Parvalbumin immunostaining revealed relatively slower maturation of Purkinje cells in the Lobule X cortex than in other lobules. Basket and stellate cells emerged in the molecular layer on PDs 21 and 42, respectively. Rosette‐like arranged glutamate decarboxylase 65 and 67‐positive puncta were observed in the inner granular layer (IGL) on PD 21. Proliferating cell nuclear antigen immunostaining appeared in the outer zone of the external granular layer (EGL) containing progenitors of granular neurons on PDs 4–21. Bergmann glial processes extending vertically through the molecular layer and EGL were visible with GFAP immunostaining on PD 10 and thereafter. Their somata, aligned in the Purkinje cell layer, showed immunopositivity to Sox2 already on PD 4 and subsequently to S100 protein on PD 10. Sox2‐positive cells were found sparsely in the IGL. Few of them were NeuN positive on PD 90, predicting the possibility of adult neurogenesis. These immunohistochemical results revealed that ferrets underwent cerebellar cortical histogenesis during their postnatal life in sequences. Relatively slow development or maturation of the ferret cerebellum was revealed by the timing of the monolayer alignment and morphological maturation of Purkinje cells.