bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of presumptive identification of Enterobacterales using CHROMagar Orientation medium and rapid biochemical tests
Authors: Ohtaki Hirofumi , Takahashi Akifumi , Niwa Ayumi , Yonetamari Jun , Nakayama Asami , Kuchibiro Tomokazu , Ohta Hirotoshi , Ito Hiroyasu , Baba Hisashi , Murakami Nobuo , Ohkusu Kiyofumi
Published: June 2020

Background

The use of matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry is gradually spreading among large‐scale laboratories; however, this method is impractical for small‐scale laboratories. In laboratories without access to these rapid identification methods, problems related to them remain unsolved. In this study, we aimed to develop a rapid and inexpensive method to presumptively identify Enterobacterales using CHROMagar Orientation medium.

Methods

The algorithm for presumptive identification of Enterobacteriaceae using CHROMagar Orientation medium was based on our previous studies. Modified property tests for indole, lysine decarboxylase, ornithine decarboxylase, and hydrogen sulfide were performed to evaluate the differentiation of the bacterial species.

Results

Using the type strains and clinical isolates, it was possible to conduct the property tests at a low cost, within 4 hours. The spot indole test was performed without any nonspecific reactions for the bacteria forming colored colonies. The presumptive identification of bacteria was thereby possible within 24 hours after specimen submission.

Conclusion

All these results suggest that the rapid presumptive identification of Enterobacterales is possible with this new identification method using CHROMagar Orientation medium. This is therefore a prompt and economical method that can be used in routine laboratory work.
Predictors of preclinical hand skill performance in dental school
Authors: Johnson, Gary M. , Stein, Amy B. , Fitzgerald, Nancy M. , Copeland Cara C. , Velazquez Daphne M. , Trowbridge Tatiyana
Published: June 2020

Context

Preclinical dental school instructors often observe some first‐year students develop hand skills required for dental procedures more quickly and more easily than their peers. When questioned regarding prior experience, these advanced students often participated in physical activities that seem to predispose them to adapt their previously learned psychomotor hand skills to those required for dentistry.

Objective

This study examines the results of an Institutional Review Board approved 22‐question survey of various lifelong predental school activities and correlations to first‐year and second‐year simulation clinic practical exam performance.

Design

The survey was taken anonymously at the Midwestern University College of Dental Medicine‐Arizona by 4 consecutive dental school classes of 2017–2020 composed of 560 students, 552 of which responded. The purpose was to discover associations between lifelong activities and practical exam scores that may act as predictors of preclinical ability to develop visualization and psychomotor hand skills required for dental procedures.

Results

Higher preclinical practical scores were found to have the most correlation with higher levels of participation in psychomotor, artistic and outdoor physical activities. Participation in computer, musical instrument and culinary activities had no significant correlation, and prior experience in the medical or dental field had a negative correlation.

Conclusion

The lack of participation in these predisposing lifelong activities may predict slower development of dental hand skills and signal the need for more hands‐on tutorial instruction in the simulation clinic so these students do not lag behind their peers.
Hamiltonicity, pancyclicity, and full cycle extendability in multipartite tournaments
Authors: Zhang Zan‐Bo , Zhang Xiaoyan , Gutin Gregory , Lou Dingjun
Published: June 2020

A digraph with vertices is Hamiltonian (pancyclic and vertex‐pancyclic, respectively) if contains a Hamilton cycle (a cycle of every length , for every vertex , a cycle of every length through , respectively.) It is well‐known that a strongly connected tournament is Hamiltonian, pancyclic, and vertex pancyclic. A digraph is cycle extendable if for every non‐Hamiltonian cycle of , there is a cycle such that contains all vertices of plus another vertex of . A cycle extendable digraph is fully cycle extendable if for every vertex , there exists a cycle of length 3 through . Note that full cycle extendability is a stronger property than vertex pancyclicity. While it is well‐known that every strongly connected tournament is vertex pancyclic, Hendry showed that not every strongly connected tournament is fully cycle extendable and characterized an infinite class of strongly connected tournaments, which are not fully cycle extendable. A ‐partite tournament is an orientation of a ‐partite complete graph (for , it is called a bipartite tournament). Gutin and later Häggkvist and Manoussakis characterized Hamiltonian bipartite tournaments. A bipartite digraph with vertices is even pancyclic (even vertex pancyclic, respectively) if contains a cycle of every even length (a cycle of every even length through for every , respectively). Beineke and Little, and Zhang proved that every bipartite tournament is even pancyclic and even vertex pancyclic, respectively, if and only if it is Hamiltonian and does not belong to a well‐defined infinite class of regular bipartite tournaments. We prove that unlike in the case of tournaments, every even pancyclic bipartite tournament is fully cycle extendable. We show that this result cannot be extended to ‐partite tournaments for any fixed (where we naturally replace even vertex pancyclicity by vertex pancyclicity).
List Ramsey numbers
Authors: Alon Noga , Bucić Matija , Kalvari Tom , Kuperwasser Eden , Szabó Tibor
Published: June 2020

We introduce a list‐coloring extension of classical Ramsey numbers. We investigate when the two Ramsey numbers are equal, and in general, how far apart they can be from each other. We find graph sequences where the two are equal and where they are far apart. For ‐uniform cliques we prove that the list Ramsey number is bounded by an exponential function, while it is well known that the Ramsey number is superexponential for uniformity at least 3. This is in great contrast to the graph case where we cannot even decide the question of equality for cliques.
k‐quasi‐transitive digraphs of large diameter
Authors: Alva‐Samos Jesús , Hernández‐Cruz César
Published: June 2020

Given an integer with , a digraph is ‐quasi‐transitive if for every ‐directed path of length in , we have or (or both). In this study, we prove that if is an odd integer, , then every strong ‐quasi‐transitive digraph of diameter at least admits a partition of its vertex set such that is Hamiltonian, and both and are semicomplete bipartite, when is bipartite, or semicomplete, otherwise. As a consequence, for an odd integer , it is easy to prove that every non‐bipartite strong ‐quasi‐transitive digraph with diameter at least has a Hamiltonian path.
Primary autoimmune myelofibrosis: A case report in a child
Authors: Hexner‐Erlichman Zufit , Yacobovich Joanne , Trougouboff Philippe , Avraham‐Kelbert Moran , Eitam Harel , Spiegel Ronen , Yeganeh Shay , Levin Carina
Published: June 2020

Autoimmune myelofibrosis (AIMF) is an uncommon cause of myelofibrosis associated with favorable outcome. Primary AIMF, AIMF without a known systemic autoimmune disorder, has been described in adults, but never in children. Here, we present, for the first time, an apparent case of primary AIMF in a 15‐year‐old boy admitted with profound hypoproliferative anemia.
Therapy related acute myeloid leukemia with blast cannibalism and cytophagocytosis
Authors: Moshref Razavi Habib , Covello Thomas
Published: June 2020

The case of an 83‐year old male patient is described. He presented to our hospital with a 2 week history of intermittent syncope and was diagnosed with atrial fibrillation. His CBC showed bicytopenia with anemia and neutropenia in context of a leucoerythroblastic blood film and blastemia. As the patient was previously diagnosed with stage IV diffuse large B cell lymphoma; treated with CHOP‐R a bone marrow biopsy was requested to rule out acute leukemia. A cellular bone marrow aspirate showed presence of a myeloblast infiltrate (32.6%; confirmed by flow cytometry). Interestingly blast phagocytosis of terminally differentiated cells along with cannibalism of other blasts was identified. The diagnosis of therapy‐related acute myeloid leukemia was reached and a palliative consultation was requested. To our knowledge, this is the first report of blast cytophagocytosis and cannibalism associated with a therapy‐related acute myeloid leukemia with a complex karyotype.
Seeking double personality: Nakamura Kokyō's work in abnormal psychology in early 20th‐century Japan
Authors: Wu Yu‐chuan
Published: June 2020

This paper examines Nakamura Kokyō's study of a woman with a split personality who lived in his home as a maid from 1917 until her death in 1940. She was his indispensable muse and assistant in his efforts to promote abnormal psychology and psychotherapy. This paper first explores the central position of multiple personality in Nakamura's theory of the subconscious, which was largely based on the model of dissociation. It then examines how it became a central issue in Nakamura's disputes with religions including the element of spirit possession, which invoked Western psychical research to modernize their doctrines. While both were concerned with the subconscious and alterations in personality, Nakamura's psychological view was distinguished from those spiritual understandings by his emphasis on individual memories, particularly those that were traumatic, and hysteria. The remaining sections of the paper will examine Nakamura's views on memory and hysteria, which conflicted with both the academic mainstream and the established cultural beliefs. This conflict may partly explain the limited success of Nakamura's academic and social campaigns.
Sodium toluene‐4‐sulfonate as a reusable and ecofriendly catalyst for greener synthesis of 5‐aminopyrazole‐4‐carbonitrile in aqueous medium
Authors: Sapkal Aboli , Kamble Santosh
Published: June 2020

In these environmentally conscious days there is need to use eco‐friendly greener technologies, such as solvent free, microwave, ultrasound and use of room temperature. Here report an efficient and green protocol for the synthesis of 5‐aminopyrazole‐4‐carbonitrile from three component condensation of phenyl hydrazine, aldehyde, and malononitrile using NaPTS as catalyst in aqueous medium. Use of water has emerged as a versatile solvent for organic reaction; it is readily available, inexpensive, environmentally benign, neutral and natural solvent. Multicomponent reactions in water are of outstanding value in organic synthesis and green chemistry. The significant features of this article are short reaction time, provide excellent yield, removal of toxic solvent and use of water as green solvent.
Synthesis of indolo[2,1‐a]isoquinolines by CF3COOH‐induced cyclization
Authors: Wada Yasuhiro , Kurono Nobuhito , Senboku Hisanori , Orito Kazuhiko
Published: June 2020

Indolo[2,1‐a]isoquinoline alkaloids and related compounds have been known to have interesting biological activities, such as antileukemic and antitumor activities. We found that 1‐(3,4‐dimethoxyphenethyl)indole gave 2,3‐dimethoxyindolo[2,1‐a]isoquinoline and 1‐(3,4‐dimethoxyphenylacetyl)indole gave 2,3‐dimethoxy‐6‐oxoindolo[2,1‐a]isoquinoline, respectively, by an intramolecular cyclization carried out in boiling trifluoroacetic acid.
Depletion of microglia in developing cortical circuits reveals its critical role in glutamatergic synapse development, functional connectivity, and critical period plasticity
Authors: Ma Xiaokuang , Chen Ke , Cui Yuehua , Huang Guanqun , Nehme Antoine , Zhang Le , Li Handong , Wei Jing , Liong Katerina , Liu Qiang , Shi Lingling , Wu Jie , Qiu Shenfeng
Published: June 2020

Microglia populate the early developing brain and mediate pruning of the central synapses. Yet, little is known on their functional significance in shaping the developing cortical circuits. We hypothesize that the developing cortical circuits require microglia for proper circuit maturation and connectivity, and as such, ablation of microglia during the cortical critical period may result in a long‐lasting circuit abnormality. We administered PLX3397, a colony‐stimulating factor 1 receptor inhibitor, to mice starting at postnatal day 14 and through P28, which depletes >75% of microglia in the visual cortex (VC). This treatment largely covers the critical period (P19‐32) of VC maturation and plasticity. Patch clamp recording in VC layer 2/3 (L2/3) and L5 neurons revealed increased mEPSC frequency and reduced amplitude, and decreased AMPA/NMDA current ratio, indicative of altered synapse maturation. Increased spine density was observed in these neurons, potentially reflecting impaired synapse pruning. In addition, VC intracortical circuit functional connectivity, assessed by laser scanning photostimulation combined with glutamate uncaging, was dramatically altered. Using two photon longitudinal dendritic spine imaging, we confirmed that spine elimination/pruning was diminished during VC critical period when microglia were depleted. Reduced spine pruning thus may account for increased spine density and disrupted connectivity of VC circuits. Lastly, using single‐unit recording combined with monocular deprivation, we found that ocular dominance plasticity in the VC was obliterated during the critical period as a result of microglia depletion. These data establish a critical role of microglia in developmental cortical synapse pruning, maturation, functional connectivity, and critical period plasticity.
Lesion network mapping demonstrates that mind‐wandering is associated with the default mode network
Authors: Philippi Carissa L. , Bruss Joel , Boes Aaron D. , Albazron Fatimah M. , Deifelt Streese Carolina , Ciaramelli Elisa , Rudrauf David , Tranel Daniel
Published: June 2020

Functional neuroimaging research has consistently associated brain structures within the default mode network (DMN) and frontoparietal network (FPN) with mind‐wandering. Targeted lesion research has documented impairments in mind‐wandering after damage to the medial prefrontal cortex (mPFC) and hippocampal regions associated with the DMN. However, no lesion studies to date have applied lesion network mapping to identify common networks associated with deficits in mind‐wandering. In lesion network mapping, resting‐state functional connectivity data from healthy participants are used to infer which brain regions are functionally connected to each lesion location from a sample with brain injury. In the current study, we conducted a lesion network mapping analysis to test the hypothesis that lesions affecting the DMN and FPN would be associated with diminished mind‐wandering. We assessed mind‐wandering frequency on the Imaginal Processes Inventory (IPI) in participants with brain injury (n = 29) and healthy comparison participants without brain injury (n = 19). Lesion network mapping analyses showed the strongest association of reduced mind‐wandering with the left inferior parietal lobule within the DMN. In addition, traditional lesion symptom mapping results revealed that reduced mind‐wandering was associated with lesions of the dorsal, ventral, and anterior sectors of mPFC, parietal lobule, and inferior frontal gyrus in the DMN (p < 0.05 uncorrected). These findings provide novel lesion support for the role of the DMN in mind‐wandering and contribute to a burgeoning literature on the neural correlates of spontaneous cognition.
Changes in reference evapotranspiration over the non‐monsoon region of China during 1961–2017: Relationships with atmospheric circulation and attributions
Authors: Dong Yiyang , Zhao Yong , Zhai Jiaqi , Zhao Jianshi , Han Jingyan , Wang Qingming , He Guohua , Chang Huanyu
Published: June 2020

Reference evapotranspiration (ET0) is an essential component of the hydrological cycle and is crucial to water resources management and assessment. Spatiotemporal variations in ET0 and their attribution to five climatic variables (maximum and minimum air temperatures, solar radiation, vapour pressure, and wind speed) were estimated for the non‐monsoon region of China from 1961–2017 meteorological data by using the Penman–Monteith equation and the partial‐differential method. The association between ET0 and atmospheric circulation patterns was explored by applying Pearson's correlation analysis. The annual ET0 series had two earlier shift points, the first showing a significant increase from 1961 to 1973 (period I) and the second showing a significant decrease from 1974 to 1994 (period II). ET0 has significantly increased again since 1994 (period III). Wind speed has been the dominant contributing factor to ET0 followed by maximum air temperature during all three periods, but the contribution gap between minimum and maximum air temperatures is narrowing. ET0 has been strongly correlated with eight selected teleconnection indices in some regions, but the locations and spatial extents have varied considerably for different indices. Eight relationships with ET0 were divided into four groups: North Atlantic Oscillation and Arctic Oscillation (mainly the northwest non‐monsoon region), Pacific North American Index and Pacific Decadal Oscillation (mainly the northern non‐monsoon region), Antarctic Oscillation and Atlantic Multidecadal Oscillation (mainly the Hexi Corridor and the southern Xinjiang), and East Asian Summer Monsoon Index and South China Sea Summer Monsoon Index (mainly the southeast non‐monsoon region). The Antarctic Oscillation, Atlantic Multidecadal Oscillation, and South China Sea Summer Monsoon Index indicated more potential for predicting ET0. When we used Pearson's correlation analysis to analyse the relationship between atmospheric circulation and the dominant factors affecting ET0, we found that the circulation patterns are likely to affect the variation in ET0 by influencing the dominant climatic variables.
Inclusion of limited amounts of extruded legumes plus cereal mixes in normocaloric or obesogenic diets for rats: effects on intestinal microbiota composition
Authors: Rubio Luis A , Aranda‐Olmedo Isabel , Contreras Soraya , Góngora Tania , Domínguez Gema , Peralta‐Sánchez Juan M , Martín‐Pedrosa Mercedes
Published: June 2020

BACKGROUND

Differences in the composition of the intestinal microbiota and energetic metabolism between lean and obese populations have been described. Legume consumption has been reported to modulate intestinal microbiota composition. However, to the best of our knowledge, no information can be found in the literature on the effects of consumption of diets containing extruded legume plus cereal mixes on the intestinal microbiota composition of rats. Our purpose was to evaluate the effects on lipids profile (see the accompanying paper) and intestinal microbiota composition (current paper) of incorporating this new food ingredient in normocaloric and obesogenic diets.

RESULTS

Intestinal and fecal qPCR‐based microbial composition of rats fed the extruded legumes plus cereal mixes differed (P < 0.05) from controls. Obesogenic diets did not affect bacterial counts. However, the inclusion of the extruded mixes reduced (P < 0.05) log10 counts in some bacterial groups and increased (P < 0.05) counts of Lactobacilli, while others remained unaffected. PCoA at the genus level grouped together Lactobacillus reuteri, Akkermansia miciniphila and species from Parabacteroides, Prevotella, Rikenellaceae, and Lactobacillus with extruded legume plus cereal diets. Feeding on extruded legumes plus cereal mixes was associated with increased mRNA expression of the cytokines IL6 and TNF‐α and decreased expression of TLR4.

CONCLUSIONS

Our results show that the inclusion in the feed of limited amounts of extruded legumes plus cereal mix, providing a diet that is closer to a normal human one, did modulate the intestinal microbiota composition. Taken together, these results point to the protective, health‐promoting properties of extruded legume plus cereal mixes.
Evaluating aggregate stability, surface properties and disintegration behaviour of bauxite residue induced by Ca/Na
Authors: Xue Shengguo , Ke Wenshun , Zhu Feng , Fan Jiarong , Wang Qiongli , Liu Zheng , Hartley William
Published: June 2020

Bauxite residue, a typical industrial solid waste which contains a large amount of Na+, is usually physically degraded. Understandings of aggregate formation, which is a critical process in soil development, are essential to facilitate ecological rehabilitation on the disposal areas. However, few studies have investigated the aggregation behaviour and mechanisms of key salt ions (Ca2+ and Na+) in residue aggregates. Therefore, an integrated method of Le Bissonnais' method, the combined determination method and laser diffraction measurements was applied to evaluate aggregate stability, surface properties and disintegration behaviour of bauxite residue following Ca/Na additions. With increasing Ca2+ addition, mean weight diameter increased, indicating improved resistance to dispersion. Ca2+ had a positive effect on flocculation of silt‐size microaggregates, while disintegration was induced following Na+ addition. Repeated laser diffraction analysis of residue samples circulating in 50 mmol L−1 electrolyte solution (Ca2+/Na+) provided a detailed view of the changes in particle size distribution as aggregates fragmented. The visualized three‐dimensional surface map revealed that Na+ promoted the disintegration of >250 μm aggregates into finer dispersed particles, while Ca2+ protected the microaggregates from fragmenting into smaller particles. Variation in electrochemical properties of aggregate surfaces affected the micro‐morphology significantly. The findings provide a new approach to specify pedogenic aggregate behavior of bauxite residue, while revealing the effects of Ca2+/Na+ on aggregate stability, surface electrochemical properties and its micromorphology. The results will provide a detailed understanding of aggregate behavior during soil formation process in bauxite residue.
A delivery quality assurance tool based on the actual leaf open times in tomotherapy
Authors: Schopfer Mathieu , Bochud François O. , Bourhis Jean , Moeckli Raphaël
Published: June 2020

Purpose

To validate a delivery quality assurance (DQA) protocol for tomotherapy based on the measurement of the leaf open times (LOTs). In addition, to show the correlation between the mean relative LOT discrepancy and the dose deviation in the planning target volume (PTV).

Materials and methods

We used a LOT measurement algorithm presented in a previous work on our two tomotherapy treatment units (TOMO1 and TOMO2).

We generated TomoPhant plans with intentional random LOT discrepancies following Gaussian distributions of −6%, −4%, −2%, 2%, 4%, and 6%. We irradiated them on the Cheese Phantom with two ion chambers and collected the raw data on both our treatment units. Using the raw data, we measured the actual LOTs and verified that the induced discrepancies were highlightable. Then, we calculated the actual dose using Accuray’s standalone dose calculator and verified that the calculated dose agreed with the ion chamber measurement.

We randomly chose 60 clinical treatment plans, delivered them in air, and collected the raw detector data. We measured the actual LOTs from the raw data and calculated the corresponding dose distributions using Accuray’s standalone dose calculator. We assessed the Pearson coefficient correlation of the deviation between expected and actual dose in the PTV (a) with the mean relative LOT discrepancy and (b) with the γ‐index pass rate for different tolerances.

Results

The mean relative discrepancy between actual (measured by the algorithm) and expected LOTs on the modified TomoPhant plans was 1.10 ± 0.05% on TOMO1 and 0.02 ± 0.03% on TOMO2, respectively. The agreement between measured and calculated dose was 0.2 ± 0.3% on TOMO1 and 0.1 ± 0.3% on TOMO2, respectively.

On clinical plans, the means of the relative LOT discrepancies ranged from −3.0 % to 1.4%. The dose deviation in the PTVs ranged from −1.6% to 2.4%. The Pearson coefficient correlation between the mean relative LOT discrepancy and the dose deviation in the PTV was 0.76 (P ≈ 10−15) on TOMO1 and 0.65 (P ≈ 10−10) on TOMO2, respectively. There was no correlation between the γ‐index pass rate and the dose deviation in the PTV.

Conclusion

The method made it possible to measure and to correctly highlight the LOT discrepancies on the TomoPhant plans. The dose subsequently calculated was accurate. On clinical plans, the mean LOT discrepancy correlated with the dose deviation in the PTV. This makes the mean LOT discrepancy a handy indicator of the plan quality.
Catfish Population Characteristics among River Segments with Altered Fluvial Geomorphic Conditions in the Missouri River, Nebraska, USA
Authors: Hamel Martin J. , Spurgeon Jonathan J. , Pegg Mark A.
Published: June 2020

Alteration of river systems around the world has created novel environments that have been fragmented, homogenized, or transformed from their natural state, thus posing challenges for understanding how fish populations function. The Missouri River has undergone significant alteration through reservoir construction and channelization. Channel Catfish Ictalurus punctatus and Flathead Catfish Pylodictis olivaris both reside in various fragmented sections of the river, and there is a substantial gap in knowledge of how catfishes synchronously function in this modified system. From 2009 to 2018, we assessed catfishes with baited hoop nets and low-frequency electrofishing among four different areas: upper and lower unchannelized segments and upper and lower channelized segments. Differences in population demographics and dynamics occurred for both species among segments. Both the highest and lowest relative abundances for Channel Catfish occurred in channelized segments, and Flathead Catfish relative abundance was lowest in both unchannelized segments. Subadult growth rates for both catfish species were greater in channelized segments. Channel Catfish mortality was highest in channelized segments, which was consistent with the maximum ages found in channelized (age 9) versus unchannelized (age 15) segments. High-flow events in 2010 and 2011 led to an increase in recruitment, but populations declined in subsequent years. This long-term assessment revealed spatial and temporal differences in population dynamics among varying levels of anthropogenic alteration. Our study illustrates how river modification and extreme climatological events may impact and structure catfish populations. These data provide a basis for assessing catfish throughout the Missouri River system and offer insight into how catfish populations in other altered large-river systems might function.
Graded energy band engineering for efficient perovskite solar cells
Authors: Cao Fengren , Wang Meng , Li Liang
Published: June 2020

Metal‐halide perovskite materials have attracted extensive attention in the field of photovoltaics due to their excellent optical and electrical properties. In just several years, the power conversion efficiency (PCE) of metal‐halide perovskite solar cells quickly increased from 3.8% to 25.2%. To further realize their theoretical PCE limit and improve their stability, matched energy levels at the interfaces among the perovskite device are critical. Appropriate energy‐level tailoring facilitates charge separation and transport, which contribute to increased open‐circuit voltage, short‐circuit current, and fill factor. In band engineering, the construction of the graded band structure can match the interfacial energy levels on both sides at the same time and provide a stronger build‐in electric field for carrier transfer. Herein, this review focuses on the graded band structure design, summarizes the recent application progress of the graded band structure in PSCs, and discusses possible promising research directions for further improvements.
Metal‐microstructure based flexible transparent electrodes and their applications in electronic devices
Authors: Xu Guiying , Li Yaowen
Published: June 2020

Novel flexible transparent electrodes (FTEs) based on metal nanoparticles/nanowires (NWs), carbon nanotubes, graphene and conductive polymers play important roles in the development of flexible and even wearable electronic devices. Among them, the metal‐nanostructure‐based FTEs present high mechanical flexibility, excellent optical/electrical properties, and low cost, so they are attracting considerable attention in recent years. In this review, we will summarize the recent progress in metal‐nanostructure FTEs, including the metal NWs, ultrathin metals, metals mesh, and composite electrodes. Moreover, we will also systematically introduce their applications in flexible electronic devices such as organic light‐emitting diodes, supercapacitors, and solar cells.
Alternate‐stacked Li4Ti5O12 nanosheets/d‐Ti3C2 flexible film as a current collector‐free, high‐capacity and robust cathode for rechargeable Mg batteries
Authors: Yang Chaoran , Yang Lanlan , Chai Zhigang , Zheng Xiang , Li Jianming , Yang Yuying , Zhu Jiefang , Jin Xu , Li Qi , Xu Dongsheng
Published: June 2020

Rechargeable magnesium batteries (RMBs) have gained increasing attention owing to its high volumetric capacity, crust abundance, and safety from dendrite‐free characteristic. However, the lack of development of high‐performance cathode materials with long cycling stability and satisfactory capacity has greatly restricted the development of RMBs. Herein, a self‐supported, current collector‐free and soft electrode is prepared with delaminated Ti3C2 (d‐Ti3C2) and Li4Ti5O12 nanosheets by simple vacuum filtration as flexible cathode in RMBs. Fabricated into a full cell with hybrid AlCl3/MgCl2/Mg(TFSI)2 electrolyte and Mg anode (a thin Mg foil with thickness of 50 μm), the flexible cathode shows high initial specific capacity of 320 mAh g−1 at 20 mA g−1, excellent cycling stability (good retention even after 1000 cycles) and outstanding rate performance. Detailed mechanistic studies reveal that introduction of d‐Ti3C2 provide fast transport paths for electrons and Mg2+. The enlarged layer spacing of composited d‐Ti3C2 accounts for significant increment in capacity. Benefiting from above‐mentioned advantages, the best performance among Ti‐based electrode materials is realized and make wearable devices powered by RMBs possible, thus circumventing the safety issues of lithium batteries.
Improving LiNixCoyMn1−x−yO2 cathode electrolyte interface under high voltage in lithium ion batteries
Authors: Wu Qian , Mao Shulan , Wang Zhuoya , Tong Yang , Lu Yingying
Published: June 2020

The demanding for high energy density as well as high safety is still an important threshold for battery commercialization. Next‐generation layered LiNixCoyMn1−x−yO2 (NCM) cathodes will meet the specific energy required for driving range of at least 300 miles from a single charge to guarantee the success of electric vehicles. Extending operating voltage of NCM cathode materials is considered as an effective way to increase energy density of lithium ion batteries. However, unstable electrode electrolyte interface (CEI) limits the electrochemical performance of NCM cathodes when operating at high voltages (>4.3 V). In this review, underlying factors and mechanisms that result in the failure to form a robust CEI are analyzed, including surface phase reconstruction, stress‐induced cracking, transition metal dissolution, electrolyte decomposition and oxygen redox reaction. Then, progress on how to improve and stabilize CEI is summarized. To bridge the gap between current and next generation automotive batteries, it is expected that the situation of NCM electrode materials at high voltage to be fine‐tuned with available variables such as nickel content, packaging density and loading level. Moreover, more detailed work on designing and studying a reliable CEI can help the application of NCM cathodes under high voltage.
Poly(maleic anhydride) copolymers‐based polymer electrolytes enlighten highly safe and high‐energy‐density lithium metal batteries: Advances and prospects
Authors: Tang Ben , Zhou Qian , Du Xiaofan , Zhang Jianjun , Zhang Huanrui , Zou Zhenyu , Zhou Xinhong , Cui Guanglei
Published: June 2020

Polymer electrolytes‐based lithium metal batteries have attracted much more attention for next‐generation energy storage devices owing to their high energy density and superior safety characteristics. However, there are still some obstacles to ameliorate interfacial compatibility between conventional polymer electrolytes with lithium metal anode and high‐voltage cathodes. It is noted that poly (maleic anhydride) copolymers (PMAC)‐based polymer electrolytes (PEs) exhibit superior interfacial compatibility with both lithium metal anode and high‐voltage cathodes in virtue of their distinctive structure. These superb characteristics will endow PMAC‐based PEs very promising candidate to develop highly safe and high‐energy‐density lithium metal batteries. So far, PMAC‐based PEs have been widely used in lithium metal batteries and high‐voltage lithium metal batteries because of their prominent advantages. Herein, recent key advances of PMAC‐based PEs are summarized. The key factors affecting ionic conductivity are elaborated in terms of structural control of PMAC, lithium salts, fillers, and plasticizers. Moreover, the interfacial compatibility of PMAC‐based PEs with lithium metal anode and high‐voltage cathodes is also discussed in details. Furthermore, potential challenges and prospects of PMAC‐based PEs are also envisioned at the end of this review. It is believed that this review will shed light on highly safe and high‐energy‐density lithium metal batteries.
How to make use of methanol in green catalytic hydrogen production?
Authors: Zhao Jiaqi , Shi Run , Li Zhenhua , Zhou Chao , Zhang Tierui
Published: June 2020

Hydrogen production and storage as the core of novel hydrogen economy attract extensive attentions in both industry and academia. Methanol‐involved hydrogen production has been considered as an alternative strategy towards conventional methane stream reforming owing to its milder reaction condition and lower carbon footprint. Currently, it mainly includes three branches: (1) thermocatalytic methanol reforming, (2) photocatalytic methanol reforming, and (3) photocatalytic water reduction using methanol as a sacrificial agent. These branches with many similarities, however, are relatively independent in their development stages and research focuses, which seriously restricted the fundamental understanding of using methanol as both hydrogen carrier and catalytic accelerant in hydrogen production reactions. We summarize latest research progresses by expounding their respective advantages, common and individual problems, as well as methods and experiences being developed. The role of methanol and its feasibility in photocatalytic hydrogen production were also discussed from both reaction mechanism and system cost‐efficiency perspectives. Finally, frontiers of the three hydrogen production approaches are prospected, providing overall guidance for the potential application of economic and environmental sustainable methanol‐mediated hydrogen energy.
Recent advances in morphology optimizations towards highly efficient ternary organic solar cells
Authors: Xu Xiaopeng , Li Ying , Peng Qiang
Published: June 2020

Organic solar cells (OSCs) have attracted considerable attention and have witnessed rapid progress in the aspects of materials design, device engineering and device physics. Ternary blend organic solar cells (TB‐OSCs), which incorporate more than two chromophores into the active blend, combine the merits of both single‐junction and tandem systems, leading to impressive device performances. However, the introduction of third component into the active blend makes the resulting morphology more complicated than the traditional binary blend. Revealing the morphology evolution and the underlying working mechanism are of great importance to guide the smart design of highly efficient TB‐OSCs. This review introduces the recent different methods that predict the miscibility, a key factor which plays an important role in morphology evolution of OSCs, and classifies the miscibility induces various morphology types of TB‐OSCs. Then, this review summarizes the recent advances in TB‐OSCs that following the above morphology types to provide an insight into the “miscibility‐morphology‐performance” relationship. Finally, challenges and perspectives toward the future development of TB‐OSCs have been presented.
Origin of functionality for functional materials at atomic scale
Authors: Xiao Dongdong , Gu Lin
Published: June 2020

The physical properties of functional materials are closely related to the intrinsic symmetry and applied fields, wherein symmetry breaking under external fields generates functionalities for functional materials that underlie various technological applications. Understanding the origin of functionalities requires us to determine the precise atomic structure and electronic configurations of functional materials in the broken‐symmetry states, thereby establishing the direct correlation between the structural details and functional properties of materials. The recent advances in aberration‐corrected transmission electron microscopy (TEM) have enabled real‐space imaging and spectroscopy at sub‐ångström resolution with extraordinary sensitivity to structure, chemistry, and bonding, providing great opportunities to bridge the gap between structure and functionality. Here we present case studies highlighting the utility of advanced TEM in understanding the origin of functionality for functional materials, alongside these examples is a discussion of the physical underpinnings of specific functional properties. We then conclude with a personal perspective on future directions as well as fundamental challenges.
Active learning method combining Kriging model and multimodal‐optimization‐based importance sampling for the estimation of small failure probability
Authors: Yang Xufeng , Cheng Xin
Published: June 2020

A novel method which combines the active learning Kriging (ALK) model with important sampling is proposed in this paper. The main aim of the proposed method is to solve problems with very small failure probability and multiple failure regions. A surrogate limit state surface (LSS) which strikes a balance between the Kriging mean and variance is proposed. In each iteration, important samples of the surrogate LSS are generated, optimal training points are chosen, the Kriging model is updated and the surrogate LSS is refined. After several iterations, the surrogate LSS will converge to the true LSS. To obtain all the local and global most probable points (MPPs) on the surrogate LSS in each iteration, a recently proposed evolutionary algorithm from the field of multimodal optimization is introduced. In this way, none of the potential failure regions is missed and the unbiasedness of the proposed method is guaranteed. The contribution factor of each MPP is defined and a weighted multimodal instrumental sampling density is formulated. In this way, more attention is paid to the more important failure regions and training points are further saved. The performance of the proposed method is verified by six case studies.
Appearance of fetal intestinal obstruction on fetal MRI
Authors: Li Xu , Zhao Zhen , Li Xuelei , Zhao Mengtian , Kefei Hu
Published: June 2020

Objective

To retrospectively analyze the imaging findings of fetal intestinal obstruction diagnosed by MRI and compare with postnatal surgery findings.

Methods

MRI data of 3346 pregnant women were retrospectively analyzed; we found 47 cases of suspected fetal small intestinal obstruction. Twenty‐nine underwent postnatal surgery.

Results

We identified one case of jejunal obstruction secondary to perforation, five annular pancreas, 10 duodenal stenoses, four jejunal stenoses, five jejunal atresias, two ileal atresias, four intestinal volvulus, and four intestinal malrotations. We further found four cases of duodenal stenosis with intestinal malrotation (two cases also showed volvulus). On fetal MRI, annular pancreas and duodenal obstruction manifested as a “double bubble.” Jejunal stenosis appeared as a “triple bubble.” Jejunal and ileal atresia mainly manifested as proximal dilatation with high signal on T1WI. Intestinal volvulus showed a sausage‐like intestinal distortion and mixed signals on T1WI and DWI sequences. Intestinal malrotations were characterized as abnormal duodenal morphology. We missed two malrotations; one jejunal obstruction was misdiagnosed.

Conclusion

Prenatal MRI can accurately determine the degree of intestinal obstruction and help qualitatively diagnose its possible etiology according to changes in MRI signals in multiple sequences, providing guidance for prenatal counseling.
Design and synthesis of poly(arylene ether sulfone)s with high glass transition temperature by introducing biphenylene groups
Authors: Liu Xin , Gao Yanwei , Zhu Xuanbo , Shang Yingshuang , Cui Zengduo , Yan Qixing , Zhang Haibo
Published: June 2020

Two novel poly(arylene ether sulfone)s with high biphenylene content (BDS‐PES and BDS‐PDBES) are prepared by nucleophilic substitution polymerization of synthesized 4,4′‐bis(4‐hydroxyphenyl)diphenyl sulfone (BDS) with 4,4′‐sulfonylbis(fluorobenzene) and 4,4‐bis[(4‐chlorophenyl)sulfonyl], respectively. The prepared polymers show high glass transition temperature and excellent high‐temperature mechanical properties. The glass transition temperature of BDS‐PDBES with higher biphenylene content is as high as 300 °C, and BDS‐PDBES can still maintain its 30% storage modulus at 295 °C. In addition, the two novel polymers also show excellent thermal stability (Td5 = 526 °C), high elongation at break (ε ≈ 20%), good tensile strength (73 MPa) and modulus (1.73 GPa) and good thermal conductivity (λ300°C = 0.28 W ·m−1 ·K−1).
Thiol–ene addition enables tailored synthesis of poly(2‐oxazoline)‐graft‐poly(vinyl pyrrolidone) copolymers for binder jetting 3D printing
Authors: Wilts Emily M , Long Timothy E
Published: June 2020

The continued interest in graft copolymer architectures arises from their unique solution properties and potential for a myriad of applications ranging from drug delivery to adhesives. Poly(vinyl pyrrolidone) (PVP) represents a popular amorphous, water‐soluble polymer used as a polymeric binder in binder jetting additive manufacturing, as fillers in cosmetic products, and for subcutaneous drug delivery systems. This report describes the synthesis of poly(2‐oxazoline) and PVP graft copolymers using a ‘grafting to’ methodology with an efficient thiol–ene ‘click’ reaction. Copolymerization of 2‐methyl‐2‐oxazoline and 2‐(3‐butenyl)‐2‐oxazoline introduced pendent vinyl grafting sites with a predictable absolute number‐average molecular weight. In parallel, reversible addition‐fragmentation chain‐transfer polymerization and subsequent aminolysis yielded well‐defined, oligomeric, thiol‐terminated PVP. Thiol–ene click chemistry enabled the formation of poly(2‐oxazoline)‐graft‐poly(vinyl pyrrolidone) (PMeOx‐g‐PVP) copolymers with varying mole percent grafting sites and PVP graft length. 1H NMR spectroscopy, aqueous SEC with multiangle light scattering (SEC‐MALS), and bromine titrations confirmed chemical structure, and DSC with TGA elucidated thermal transitions. Aqueous SEC‐MALS and 1H NMR spectroscopy also determined absolute number‐ and weight‐average molecular weights and average grafting levels, which revealed optimal reaction conditions. Zero‐shear viscosities of 5 and 10 wt% solutions in deionized water for each graft copolymer compared to their linear analogs demonstrated a significant (ca 31%) decrease in viscosity at the same number‐average molecular weight. This decrease in solution viscosity suggested PMeOx‐g‐PVP copolymers as exceptional alternatives to linear analogs for aqueous‐based, binder jetting additive manufacturing.
On the photophysics of a polyene dissolved in n‐alkanes when the temperature drops from 293 to 77 K
Authors: Catalán Javier
Published: June 2020

The odd–even behavior of n‐alkanes shows that polyene molecules can be minority trapped in the crystalline phase of these saturated compounds, forcing to the fraction of trapped polyenes to adopt an all‐trans structure very close to coplanar. This evidence helps us explain the photophysical behavior of these important compounds based on conformational changes of their molecular structure.
Enhanced uptake of drip‐applied flonicamid by arbuscular mycorrhizal fungi and improved control of cotton aphid
Authors: Jiang Hui , Tian Yongqing , Chen Jianjun , Zhang Zhixiang , Xu Hanhong
Published: June 2020

BACKGROUND

Drip application of insecticides has been used for controlling crop pests, but the application doses are usually higher than those used for foliar spray. Arbuscular mycorrhizal fungi (AMF) have been reported to improve root absorption of nutrients from soil, which may also enhance the uptake of drip‐applied insecticides, reducing application doses. In this study, greenhouse and field experiments were carried out to determine if AMF could colonize cotton roots, if the colonization could enhance the absorption of drip‐applied flonicamid, and if the enhanced uptake could reduce flonicamid application dose, while maintaining control efficacy against cotton aphid.

RESULTS

The applied AMF effectively colonized cotton roots and significantly promoted root growth. Fresh weights of cotton roots inoculated with multiple AMF were 28% greater than those of uninoculated plants. Multiple AMF colonization significantly increased flonicamid concentrations in leaves, which were 44.5–139.7% higher than for non AMF‐colonized roots, corresponding to 3.7–31.8% increases in corrected mortalities of cotton aphid compared with uninoculated plants. AMF colonization reduced the application rate of flonicamid and the residue level of flonicamid in soil.

CONCLUSION

Drip application of flonicamid to cotton roots inoculated with AMF represents a new approach to insecticide application. AMF colonization increased flonicamid uptake, improved aphid control efficacy and reduced flonicamid application rates. © 2020 Society of Chemical Industry
Introgressive hybridization between two non‐native apple snails in China: widespread hybridization and homogenization in egg morphology
Authors: Yang Qian‐Qian , He Chao , Liu Guang‐Fu , Yin Chuan‐Lin , Xu Yi‐Peng , Liu Su‐Wen , Qiu Jian‐Wen , Yu Xiao‐Ping
Published: June 2020

BACKGROUND

Apple snails from the genus Pomacea have spread widely in paddy fields and other wetlands of southern China since their introduction in the 1980s. Pomacea spp. are commonly identified using mitochondrial COI sequences. However, sequencing the nuclear elongation factor 1‐alpha (EF1α) gene revealed genetic introgression between field populations of P. canaliculata and P. maculata, which produce surviving hybrids in laboratory crossbreeding experiments.

RESULTS

In this study, we sequenced 1054 EF1α clones to design specific primers and established a fast and accurate multiplex polymerase chain reaction (PCR) method for genotyping EF1α. Combined with genotyping P. canaliculata and P. maculata based on mitochondrial COI and nuclear EF1α, we revealed the genetic introgression patterns of 30 apple snail populations in China. Purebred and hybrid individuals of P. canaliculata were widely distributed, while pure maculata‐EF1α type was detected only in a few individuals identified as P. canaliculata based on COI sequences. Each egg clutch had one to three genetic patterns, indicating multiple paternity or segregation in the progeny of hybrids. The higher percentages of hybrids in both wild populations and progeny than the homozygotes indicated a potential heterosis in the apple snail populations. Additionally, egg size and clutch size of the apple snails became homogeneous among the non‐native populations exhibiting introgression hybridization.

CONCLUSION

Our findings emphasize the value of apple snails as a model to study the mechanisms and impacts of introgressive hybridization on fitness traits. © 2020 Society of Chemical Industry