bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pseudo‐Membrane Jackets: Two‐Dimensional Coordination Polymers Achieving Visible Phase Separation in Cell Membrane
Authors: Ohtani Ryo , Kawano Kenichi , Kinoshita Masanao , Yanaka Saeko , Watanabe Hikaru , Hirai Kenji , Futaki Shiroh , Matsumori Nobuaki , Uji‐i Hiroshi , Ohba Masaaki , Kato Koichi , Hayami Shinya 
Published: July 2020

AbstractCell membranes contain lateral systems that consist of various lipid compositions and actin cytoskeleton, providing two‐dimensional (2D) platforms for chemical reactions. However, such complex 2D environments have not yet been used as a synthetic platform for artificial 2D nanomaterials. Herein, we demonstrate the direct synthesis of 2D coordination polymers (CPs) at the liquid‐cell interface of the plasma membrane of living cells. The coordination‐driven self‐assembly of networking metal complex lipids produces cyanide‐bridged CP layers with metal ions, enabling “pseudo‐membrane jackets” that produce long‐lived micro‐domains with a size of 1–5 μm. The resultant artificial and visible phase separation systems remain stable even in the absence of actin skeletons in cells. Moreover, we show the cell application of the jackets by demonstrating the enhancement of cellular calcium response to ATP.
Grubbs Metathesis Enabled by a Light‐Driven gem‐Hydrogenation of Internal Alkynes
Authors: Biberger Tobias , Zachmann Raphael J. , Fürstner Alois 
Published: July 2020

Abstract[(NHC)(cymene)RuCl2] (NHC=N‐heterocyclic carbene) complexes instigate a light‐driven gem‐hydrogenation of internal alkynes with concomitant formation of discrete Grubbs‐type ruthenium carbene species. This unorthodox reactivity mode is harnessed in the form of a “hydrogenative metathesis” reaction, which converts an enyne substrate into a cyclic alkene. The intervention of ruthenium carbenes formed in the actual gem‐hydrogenation step was proven by the isolation and crystallographic characterization of a rather unusual representative of this series carrying an unconfined alkyl group on a disubstituted carbene center.
Electrocatalysis as the Nexus for Sustainable Renewable Energy: The Gordian Knot of Activity, Stability, and Selectivity
Authors: Masa Justus , Andronescu Corina , Schuhmann Wolfgang 
Published: July 2020

AbstractThe use of renewable energy by means of electrochemical techniques by converting H2O, CO2 and N2 into chemical energy sources and raw materials, is the basis for securing a future sustainable “green” energy supply. Some weaknesses and inconsistencies in the practice of determining the electrocatalytic performance, which prevents a rational bottom‐up catalyst design, are discussed. Large discrepancies in material properties as well as in electrocatalytic activity and stability become obvious when materials are tested under the conditions of their intended use as opposed to the usual laboratory conditions. They advocate for uniform activity/stability correlations under application‐relevant conditions, and the need for a clear representation of electrocatalytic performance by contextualization in terms of functional investigation or progress towards application is emphasized.
LeafMachine: Using machine learning to automate leaf trait extraction from digitized herbarium specimens
Authors: Weaver William N. , Ng Julienne , Laport Robert G. 
Published: July 2020

PremiseObtaining phenotypic data from herbarium specimens can provide important insights into plant evolution and ecology but requires significant manual effort and time. Here, we present LeafMachine, an application designed to autonomously measure leaves from digitized herbarium specimens or leaf images using an ensemble of machine learning algorithms.Methods and ResultsWe trained LeafMachine on 2685 randomly sampled specimens from 138 herbaria and evaluated its performance on specimens spanning 20 diverse families and varying widely in resolution, quality, and layout. LeafMachine successfully extracted at least one leaf measurement from 82.0% and 60.8% of high‐ and low‐resolution images, respectively. Of the unmeasured specimens, only 0.9% and 2.1% of high‐ and low‐resolution images, respectively, were visually judged to have measurable leaves.ConclusionsThis flexible autonomous tool has the potential to vastly increase available trait information from herbarium specimens, and inform a multitude of evolutionary and ecological studies.
Breast cancer survivors' risk of interval cancers and false positive results in organized mammography screening
Authors: Njor Sisse Helle , Vejborg Ilse , Larsen Mette Bach 
Published: July 2020

AbstractBackgroundBreast cancer survivors are increasing followed for new breast cancers / recurrences by mammography screening only. We aimed at assessing how often breast cancer survivors get a false positive or false negative result at mammography screening.MethodsAll mammography screenings performed between 2007 and 2017 in the Danish national mammography screening programme were included. Screenings in women with a breast cancer diagnosis prior to invitation were included in the “breast cancer survivors” group, while remaining screenings were included in the “no previous breast cancer” group. We compared the proportion of false positive screenings and the proportion of breast cancers detected at screening among breast cancer survivors and women without previous breast cancer. The analyses were further stratified according to whether the women had a diagnostic breast imaging in the 21 months prior to the screening.ResultsAt initial screenings, breast cancer survivors had a significant lower false positive risk than other women, while the risk was similar at subsequent screenings. Breast cancer survivors had a significant lower proportion of breast cancers detected at screening compared to other women. This was true both for women who had a diagnostic breast imaging in the 21 months prior to screening and those who did not.ConclusionThis study shows that breast cancers survivors have a smaller amount of their new breast cancers detected at mammography screening, when compare to the amount of new breast cancers detected at mammography screening among women without previous breast cancer. The lower sensitivity does not seem to be due to different behavior among breast cancer survivors.
Genetic‐Code‐Expansion Strategies for Vaccine Development
Authors: Fok Jelle A. , Mayer Clemens 
Published: July 2020

AbstractAbstract: By providing long‐term protection against infectious diseases, vaccinations have significantly reduced death and morbidity worldwide. In the 21st century, (bio)technological advances have paved the way for developing prophylactic vaccines that are safer and more effective as well as enabling the use of vaccines as therapeutics to treat human diseases. Here, we provide a focused review of the utility of genetic code expansion as an emerging tool for the development of vaccines. Specifically, we discuss how the incorporation of immunogenic noncanonical amino acids can aid in eliciting immune responses against adverse self‐proteins and highlight the potential of an expanded genetic code for the construction of replication‐incompetent viruses. We close the review by discussing the future prospects and remaining challenges for the application of these approaches in the development of both prophylactic and therapeutic vaccines in the near future.
Human Cellular Retinol Binding Protein II Forms a Domain‐Swapped Trimer Representing a Novel Fold and a New Template for Protein Engineering
Authors: Ghanbarpour Alireza , Santos Elizabeth M. , Pinger Cody , Assar Zahra , Hossaini Nasr Seyedmehdi , Vasileiou Chrysoula , Spence Dana , Borhan Babak , Geiger James H. 
Published: July 2020

AbstractDomain‐swapping is a mechanism for evolving new protein structure from extant scaffolds, and has been an efficient protein‐engineering strategy for tailoring functional diversity. However, domain swapping can only be exploited if it can be controlled, especially in cases where various folds can coexist. Herein, we describe the structure of a domain‐swapped trimer of the iLBP family member hCRBPII, and suggest a mechanism for domain‐swapped trimerization. It is further shown that domain‐swapped trimerization can be favored by strategic installation of a disulfide bond, thus demonstrating a strategy for fold control. We further show the domain‐swapped trimer to be a useful protein design template by installing a high‐affinity metal binding site through the introduction of a single mutation, taking advantage of its threefold symmetry. Together, these studies show how nature can promote oligomerization, stabilize a specific oligomer, and generate new function with minimal changes to the protein sequence.
Are unusual ultrastructural features occurring in the pollen endomembrane system of Cyperaceae and other angiosperms?
Authors: Rocha Danilo M. , Vanzela André L. L. , Mariath Jorge E. A. 
Published: July 2020

AbstractCyperaceae representatives present peculiar microsporogenesis and microgametogenesis, which raises the question of how regular the sedge pollen is. In order to answer this question, preanthesis pollen grains of Cyperaceae individuals were analyzed under different tools such as light and transmission electron microscopy, which included cytochemistry and immunogold procedures. The results showed that maturing pollen in Cyperaceae presents some unusual endomembrane behaviors. Endoplasmic reticulum and dictyosomes are concerned in classic secretion pathways in vegetative cells, and possibly the late breakdown of degenerative microspores. However, cortical and concentric endoplasmic reticulum are also present and are possibly related to other functions aside the biosynthetic pathway. Unconventional secretion of large membrane‐bound bodies containing cell wall precursors was also observed and confirmed by immunogold. However, since these bodies most likely receive material from dictyosomes, as observed in silver nitrate reaction, the “unconventional” status of this secretion is debatable. Reports of the literature show that these unusual endomembrane formations are not exclusive of the sedge pollen, but little attention have been given to them so far. This could represent an opportunity to re‐examine our understanding on the endomembrane system in pollen cells in general.
Technical and Economic Analysis of Conventional and Supercritical Transesterification for Biofuel Production
Authors: Nguyen Dinh Duc , Habibi Ali , Ghadami Azam , Pirouzfar Vahid , Su Chia-Hung 
Published: July 2020

AbstractThe transesterification process with potassium hydroxide (KOH) catalyst and the methanol supercritical process were evaluated by Aspen HYSYS software. Castor oil and methanol were used as feed and alcohol. In order to accomplish verification, the simulation results were compared to a laboratory research. For economic analysis, these results were transferred to Aspen Economic Analyzer software. Piping and process equipment cost were calculated for the two processes. Additionally, direct and indirect costs of these processes were estimated.
Establishing Primary Cultures of Trunk Neural Crest Cells
Authors: Duband Jean‐Loup , Nekooie‐Marnany Nioosha , Dufour Sylvie 
Published: July 2020

AbstractNeural crest cells constitute a unique population of progenitor cells with extensive stem cell capacities able to navigate throughout various environments in the embryo and are a source of multiple cell types, including neurons, glia, melanocytes, smooth muscles, endocrine cells, cardiac cells, and also skeletal and supportive tissues in the head. Neural crest cells are not restricted to the embryo but persist as well in adult tissues where they provide a reservoir of stem cells with great therapeutic promise. Many fundamental questions in cell, developmental, and stem cell biology can be addressed using this system. During the last decades there has been an increased availability of elaborated techniques, animal models, and molecular tools to tackle neural crest cell development. However, these approaches are often very challenging and difficult to establish and they are not adapted for rapid functional investigations of mechanisms driving cell migration and differentiation. In addition, they are not adequate for collecting pure populations of neural crest cells usable in large scale analyses and for stem cell studies. Transferring and adapting the neural crest system in tissue culture may then represent an attractive alternative, opening up numerous prospects. Here we describe a simple method for establishing primary cultures of neural crest cells derived from trunk neural tubes using the avian embryo as a source of cells. This protocol is suited for producing pure populations of neural crest cells that can be processed for cytological, cellular, and functional approaches aimed at characterizing their phenotype, behavior, and potential. © 2020 Wiley Periodicals LLC.Basic Protocol: Primary cultures of avian trunk neural crest cellsSupport Protocol: Adaptations for immunofluorescence labeling and videomicroscopy
Designing Hole Transport Materials with High Hole Mobility and Outstanding Interface Properties for Perovskite Solar Cells
Authors: Jiang Rui , Zhu Rui , Li Ze‐Sheng 
Published: July 2020

AbstractOrganic–inorganic halide perovskite solar cells (PSCs) have attracted much attention due to their rapid increase in power conversion efficiencies (PCEs), and many efforts are devoted to further improving the PCEs. Designing highly efficient hole transport materials (HTMs) for PSCs may be one of the effective ways. Herein we theoretically designed three new HTMs (FDT−N, FDT−O, and FDT−S) by introducing a nitrogen‐phenyl group, an oxygen atom, and a sulfur atom into the spiro core of an experimentally synthesized HTM (FDT), respectively. And then we performed quantum chemical calculation to study their application potential. The results show that the devices with FDT−O and FDT−S instead of FDT may have higher open circuit voltages owing to their lower highest occupied molecular orbital (HOMO) energy levels. Moreover, FDT−S exhibits the best hole transport performance among the studied HTMs, which may be due to the significant HOMO‐HOMO overlap in the hole hopping path with the largest transfer integral. Furthermore, the results on interface properties indicate that introducing oxygen and sulfur atoms can enhance the MAPbI3/HTM interface interaction. The present work not only offers two promising HTMs (FDT−O and FDT−S) for PSCs but also provides theoretical help for subsequent research on HTMs.
Unexpected food web responses to low dissolved oxygen in an estuarine fjord
Authors: Moriarty Pamela E. , Essington Timothy E. , Horne John K. , Keister Julie E. , Li Lingbo , Parker‐Stetter Sandra L. , Sato Mei 
Published: July 2020

AbstractIn coastal marine ecosystems, the depletion of dissolved oxygen can cause behavioral and distributional shifts of organisms and thereby alter ecological processes. We used the spatiotemporal variation in the onset and intensity of low dissolved oxygen in Hood Canal, Washington, USA, to investigate consequences of seasonally reduced oxygen on fish–zooplankton predator–prey interactions. By simultaneously monitoring densities of zooplankton (primarily the euphausiid; Euphausia pacifica) and zooplanktivorous fish (Pacific herring, Clupea pallasii, and Pacific hake, Mercluccius productus), and the feeding of zooplanktivorous fish, we could separate the effects of dissolved oxygen on fish–zooplankton interactions from other seasonal changes. We expected that fish predators (especially Pacific herring) would be less abundant and have lower feeding rates when oxygen levels declined below biological thresholds, and that this would result in increased zooplankton abundance in areas with lowest dissolved oxygen. However, these expectations were not borne out. Overall, there was mixed evidence for an effect of dissolved oxygen on many of our response variables, and when effects were detected, they were frequently in the opposite direction of our expectations. Specifically, the pelagic fish community became more abundant (as measured by increasing acoustic backscatter), which was particularly pronounced for Pacific herring. Zooplankton had weak evidence for a response to dissolved oxygen, but the direction was negative instead of positive. Although predator feeding composition was unrelated to dissolved oxygen, stomach fullness (an index of feeding intensity) of Pacific herring declined, as per our expectations. These unexpected findings highlight the importance of in situ measurements of multiple aspects of predator–prey linkages in response to environmental stress to enhance our ability to predict ecological consequences of declining oxygen.
The use of the CALL Risk Score for predicting mortality in Brazilian heart failure patients
Authors: Nakazone Marcelo Arruda , Otaviano Ana Paula , Machado Maurício Nassau , Bestetti Reinaldo Bulgarelli 
Published: July 2020

AbstractAimsThis study aimed to develop and validate a simple method for predicting long‐term all‐cause mortality in ambulatory patients with chronic heart failure (CHF) residing in an area where Chagas disease is endemic, which will be important not only for patients living in Latin America but also to those living in developed non‐endemic countries.Methods and resultsA total of 677 patients with a wide spectrum of aetiologies for left ventricular systolic dysfunction and receiving optimized evidence‐based treatment for CHF were prospectively followed for approximately 11 years. We established a risk score using Cox proportional hazard regression models. After multivariable analysis, four variables were independently associated with mortality and included in the CALL Risk Score: Chagas cardiomyopathy aetiology alone [hazard ratio, 3.36; 95% confidence interval (CI), 2.61–4.33; P < 0.001], age ≥60 years (hazard ratio, 1.36; 95% CI, 1.06–1.74; P = 0.016), left anterior fascicular block (hazard ratio, 1.64; 95% CI, 1.27–2.11; P < 0.001), and left ventricular ejection fraction <40% (hazard ratio, 1.73; 95% CI, 1.30–2.28; P < 0.001). The internal validation considered the bootstrapping, a resampling technique recommended for prediction model development. Hence, we established a scoring system attributing weights according to each risk factor: 3 points for Chagas cardiomyopathy alone, 1 point for age ≥60 years, and 2 points each for left anterior fascicular block and left ventricular ejection fraction <40%. Three risk groups were identified: low risk (score ≤2 points), intermediate risk (score of 3 to 5 points), and high risk (score ≥6 points). High‐risk patients had more than two‐fold increase in mortality (26.9 events/100 patient‐years) compared with intermediate‐risk patients (10.1 events/100 patient‐years) and almost seven‐fold increase compared with low‐risk patients (4.3 events/100 patient‐years). The CALL Risk Score data sets from the development and internal validation cohorts both displayed suitable discrimination c‐index of 0.689 (95% CI, 0.688–0.690; P < 0.001) and 0.687 (95% CI, 0.686–0.688; P < 0.001), respectively, and satisfactory calibration [Greenwood–Nam–D'Agostino test (8) = 7.867; P = 0.447] and [Greenwood–Nam–D'Agostino test (8) = 10.08; P = 0.273], respectively.ConclusionsThe CALL Risk Score represents a simple and validated method with a limited number of non‐invasive variables that successfully predicts long‐term all‐cause mortality in a real‐world cohort of patients with CHF. Patients with CHF stratified as high risk according to the CALL Risk Score should be monitored and aggressively managed, including those with CHF secondary to Chagas disease.
Biventricular imaging markers to predict outcomes in non‐compaction cardiomyopathy: a machine learning study
Authors: Rocon Camila , Tabassian Mahdi , Tavares de Melo Marcelo Dantas , de Araujo Filho Jose Arimateia , Grupi Cesar José , Parga Filho Jose Rodrigues , Bocchi Edimar Alcides , D'hooge Jan , Salemi Vera Maria Cury 
Published: July 2020

AbstractAimsLeft ventricular non‐compaction cardiomyopathy (LVNC) is a genetic heart disease, with heart failure, arrhythmias, and embolic events as main clinical manifestations. The goal of this study was to analyse a large set of echocardiographic (echo) and cardiac magnetic resonance imaging (CMRI) parameters using machine learning (ML) techniques to find imaging predictors of clinical outcomes in a long‐term follow‐up of LVNC patients.Methods and resultsPatients with echo and/or CMRI criteria of LVNC, followed from January 2011 to December 2017 in the heart failure section of a tertiary referral cardiologic hospital, were enrolled in a retrospective study. Two‐dimensional colour Doppler echocardiography and subsequent CMRI were carried out. Twenty‐four hour Holter monitoring was also performed in all patients. Death, cardiac transplantation, heart failure hospitalization, aborted sudden cardiac death, complex ventricular arrhythmias (sustained and non‐sustained ventricular tachycardia), and embolisms (i.e. stroke, pulmonary thromboembolism and/or peripheral arterial embolism) were registered and were referred to as major adverse cardiovascular events (MACEs) in this study. Recruited for the study were 108 LVNC patients, aged 38.3 ± 15.5 years, 48.1% men, diagnosed by echo and CMRI criteria. They were followed for 5.8 ± 3.9 years, and MACEs were registered. CMRI and echo parameters were analysed via a supervised ML methodology. Forty‐seven (43.5%) patients had at least one MACE. The best performance of imaging variables was achieved by combining four parameters: left ventricular (LV) ejection fraction (by CMRI), right ventricular (RV) end‐systolic volume (by CMRI), RV systolic dysfunction (by echo), and RV lower diameter (by CMRI) with accuracy, sensitivity, and specificity rates of 75.5%, 77%, 75%, respectively.ConclusionsOur findings show the importance of biventricular assessment to detect the severity of this cardiomyopathy and to plan for early clinical intervention. In addition, this study shows that even patients with normal LV function and negative late gadolinium enhancement had MACE. ML is a promising tool for analysing a large set of parameters to stratify and predict prognosis in LVNC patients.