bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 5H‐Selenopheno[3,2‐c]isochromen‐5‐ones Promoted by Dialkyl Diselenides and Oxone®
Authors: Goulart Helen A. , Neto José S. S. , Barcellos Angelita M. , Barcellos Thiago , Silva Márcio S. , Alves Diego , Jacob Raquel G. , Lenardão Eder J. , Perin Gelson 
Published: May 2019

AbstractWe describe here for the first time the synthesis of isochromenones fused to selenophenes. 5H‐Selenopheno[3,2‐c]isochromen‐5‐ones were obtained through a double intramolecular cyclization of methyl 2‐(organyl‐1,3‐diynyl)benzoate promoted by electrophilic species of selenium generated in situ by the reaction of dialkyl diselenides with Oxone®, using ethanol as solvent. The reactions were conducted satisfactorily under mild conditions, using a range of 1,3‐diynes and dialkyl diselenides as substrates. A total of sixteen unprecedent 5H‐selenopheno[3,2‐c]isochromen‐5‐ones were selectively obtained in moderate to good yields (40–86%) under reflux in an open flask and in short reaction times (1.0–2.5 h).magnified image
Palladium(II)‐Catalyzed Intermolecular Cascade Cyclization of Methylenecyclopropanes with Aromatic Alkynes: Construction of Spirocyclic Compounds Containing Indene and 1,2‐Dihydronaphthalene Moieties
Authors: Fang Wei , Wei Yin , Shi Min 
Published: May 2019

AbstractA palladium(II)‐catalyzed intermolecular cascade cyclization of methylenecyclopropanes with aromatic alkynes is reported in this paper. The reaction involves a migratory insertion of alkyne, an intramolecular Heck‐type reaction, and β‐H elimination, providing a series of spirocyclic compounds containing indene and 1,2‐dihydronaphthalene moieties in moderate to excellent yields upon heating.magnified image
Enantioselective Construction of Bispirooxindoles via Squaramide‐Catalysed Cascade Michael/Cyclization Reaction
Authors: Zhao Bo‐Liang , Lin Ye , Du Da‐Ming 
Published: May 2019

AbstractA series of readily available 2‐(2‐oxoindolin‐3‐yl)malononitriles bearing multiple active sites were first used in asymmetric catalytic synthesis, which have been successfully applied to develop a bifunctional squaramide‐catalyzed cascade Michael/cyclization reaction strategy. Various cyclopentene‐bispirooxindoles with three continuous stereocenters, two of which are quaternary spiro‐stereocenters, were constructed in good yields with excellent stereoselectivities (up to >20:1 dr, >99% ee).magnified image
Dual‐Band Terahertz Auto‐Focusing Airy Beam Based on Single‐Layer Geometric Metasurfaces with Independent Complex Amplitude Modulation at Each Wavelength
Authors: Wang Tailei , Zhai Guohua , Xie Rensheng , Zhu Shouzheng , Gao Jianjun , An Sensong , Zheng Bowen , Li Hang , Liu Yong , Zhang Hualiang , Ding Jun 
Published: May 2019

AbstractThe Airy beam has attracted considerable interests due to its remarkable non‐diffracting, self‐bending, and self‐healing properties. An auto‐focusing Airy (AFA) beam can be achieved by constructing two counter‐propagation Airy beams, which is a novel method to generate focusing effect. Traditionally, because of the complexity of the generation mechanism, it is hard to realize the Airy beam with complex amplitude modulation. The reported ones usually require bulky optical systems and typically work at one single wavelength. Here, a general scheme is proposed to launch dual‐band Airy and AFA beams based on the single‐layer geometric metasurface, consisting of a newly designed meta‐atom that can realize independent complex amplitude modulations at two arbitrary terahertz wavelengths. Based on the proposed meta‐atom, the aforementioned attractive properties of the Airy beam are demonstrated at two terahertz wavelengths. Besides, the dual‐band AFA beams are illustrated to have the practically important adjustability of the focal length. Furthermore, owing to the self‐healing property, the proposed focusing scheme (i.e., AFA beam) shows a much better capability of circumventing the PEC obstacles compared to the conventional metalens, which could have potential applications in various important scenarios such as biomedical imaging/therapy and nondestructive evaluation with compact size and multiwavelength functionalities.
Improving Operational Stability of p‐Type Field‐Effect Transistors by Charge Selective Electrodes: a General Strategy
Authors: Zhou Guodong , Zhou Shuang , Zhu Qiang , Zhao Ni 
Published: May 2019

AbstractOperational instability caused by unintentional electron injection is a common problem for field‐effect transistors (FETs) based on relatively narrow‐bandgap semiconductors. Typically, the electron injection is followed by electron trapping at the semiconductor/dielectric interface or sometimes in the bulk semiconductor, resulting in a modification of the built‐in field in the FETs. Such a dynamic process causes continuous threshold voltage or Dirac voltage (Vth/Dirac) shift and thus unstable device operation. A charge‐selective electrode (CSE) design is used to address these problems. The CSE is formed by inserting a molybdenum trioxide interlayer between the electrode and the semiconductor, which creates an energy barrier to block electron injection. It is shown that the CSE strategy can generally work for FETs based on three semiconductor families, namely conjugated polymer, graphene, and quantum dot, and greatly suppresses the Vth/Dirac shift, enhancing the bias stress stability as well as reducing the noise level of the FETs. The mechanism for CSE‐reduced bias stress is investigated through trap analysis. CSE is a general strategy for achieving stable and low‐noise operation of unipolar FETs. The device design concept can be applied to other device configurations.
Photovoltaic–Pyroelectric–Piezoelectric Coupled Effect Induced Electricity for Self‐Powered Coupled Sensing
Authors: Ji Yun , Wang Yuanhao , Yang Ya 
Published: May 2019

AbstractMultifunctional sensors have attracted great interests as potential candidates for application of human health and ambient circumstance monitoring devices. Recent investigations are focused on novel materials or device structure to achieve simultaneously detecting various stimulations. Here, the photovoltaic–pyroelectric–piezoelectric coupled effect induced electricity for self‐powered coupled sensing in ferroelectric BaTiO3 material is reported, which can be utilized to detect light intensity, temperature variation, and vibration frequency with the sensitivities of 0.17 nA (mW cm−2)−1, 4.80 nA K−1, 21.02 nA Hz−1 (≤17 Hz), respectively. The sensitivities for the light+temperature, temperature+vibration, and light+temperature+vibration monitoring of the device are found to depend on the variation of spontaneous polarization in the BaTiO3 material. This work provides an inspiration to achieve individual/simultaneous light, temperature, and vibration sensing by employing ferroelectric materials, which greatly simplifies the structure of a multifunctional sensor, and holds significant potentials for self‐powered sensing in healthcare and ambient environment monitoring fields.
Uniform High Ionic Conducting Lithium Sulfide Protection Layer for Stable Lithium Metal Anode
Authors: Chen Hao , Pei Allen , Lin Dingchang , Xie Jin , Yang Ankun , Xu Jinwei , Lin Kaixiang , Wang Jiangyan , Wang Hansen , Shi Feifei , Boyle David , Cui Yi 
Published: May 2019

AbstractArtificial solid‐electrolyte interphase (SEI) is one of the key approaches in addressing the low reversibility and dendritic growth problems of lithium metal anode, yet its current effect is still insufficient due to insufficient stability. Here, a new principle of “simultaneous high ionic conductivity and homogeneity” is proposed for stabilizing SEI and lithium metal anodes. Fabricated by a facile, environmentally friendly, and low‐cost lithium solid‐sulfur vapor reaction at elevated temperature, a designed lithium sulfide protective layer successfully maintains its protection function during cycling, which is confirmed by both simulations and experiments. Stable dendrite‐free cycling of lithium metal anode is realized even at a high areal capacity of 5 mAh cm−2, and prototype Li–Li4Ti5O12 cell with limited lithium also achieves 900 stable cycles. These findings give new insight into the ideal SEI composition and structure and provide new design strategies for stable lithium metal batteries.
Triggering the Passivation Effect of Potassium Doping in Mixed‐Cation Mixed‐Halide Perovskite by Light Illumination
Authors: Zheng Fei , Chen Weijian , Bu Tongle , Ghiggino Kenneth P. , Huang Fuzhi , Cheng Yibing , Tapping Patrick , Kee Tak W. , Jia Baohua , Wen Xiaoming 
Published: May 2019

AbstractPotassium (K+) doping has been recently discovered as an effective route to suppress hysteresis and improve the performance stability of perovskite solar cells. However, the mechanism of these K+ doping effects is still under debate, and rationalization of the improved performance in these perovskites is needed. Herein, the photoluminescence (PL) properties and device performance of mixed‐cation mixed‐halide perovskite are dynamically monitored with and without K+ doping under bias light illumination via a confocal fluorescence microscope, together with ultrafast transient absorption as well as time‐dependent and time‐resolved PL measurements. It is demonstrated that illumination is essential to trigger the passivation effect of K+ by forming KBr‐like compounds, leading to the elimination of interface trapping defects and suppression of mobile ion migration, thus resulting in improved power conversion efficiency and negligible current–voltage hysteresis of solar cells. This work provides novel insight into the hysteresis suppression upon K+ doping and highlights the significance of light illumination when using this protocol.
Total neoadjuvant therapy in locally advanced rectal cancer: Role of systemic chemotherapy
Authors: Yoo Ri Na , Kim Hyung Jin 
Published: May 2019

AbstractFor the past several decades, disease‐related outcomes, particularly local recurrence rate, in patients with locally advanced rectal cancer have significantly improved as a result of advancement of surgical technique and implementation of neoadjuvant chemoradiation. However, distant metastasis remains unresolved, being a significant cause of cancer death. To focus on micrometastases early in the course of multimodal treatment, delivering systemic chemotherapy in the neoadjuvant setting is emerging. Also, driven by patient demand and interest in preserving quality of life, upfront chemotherapy prior to surgery serves as a strategy for organ preservation in the management of rectal cancer. Herein, currently available literature on different methods and strategies of the multimodal approach is critically appraised.
Palatal evaluation and treatment in 22q11.2 deletion syndrome
Authors: Jackson Oksana , Crowley T. Blaine , Sharkus Robert , Smith Robert , Jeong Stephanie , Solot Cynthia , McDonald‐Mcginn Donna 
Published: May 2019

AbstractPalatal involvement occurs commonly in patients with 22q11.2 Deletion Syndrome (22qDS), and includes palatal clefting and velopharyngeal dysfunction in the absence of overt or submucous clefts. The reported incidence and distribution of palatal abnormalities vary in the literature. The aim of this article is to revisit the incidence and presenting features of palatal abnormalities in a large cohort of patients with 22qDS, summarize the surgical treatments performed in this cohort, and provide an overview of surgical treatment protocols and management guidelines for palatal abnormalities in this syndrome. Charts of 1,121 patients seen through the 22q and You Center at the Children's Hospital of Philadelphia were reviewed for palatal status, demographic factors, deletion size, and corrective surgical procedures. Statistical analysis was performed using Pearson's chi‐squared test to identify differences between gender, deletion size, and palatal abnormality. Of the patients with complete evaluations, 67% were found to have a palatal abnormality. The most common finding was velopharyngeal dysfunction in 55.2% of patients, and in 33.3% of patients, this occurred in the absence of palatal clefting. There was no significant difference in the incidence of palatal abnormalities by gender; however, a difference was noted among race (p < 0.01) and deletion sizes (p < 0.01). For example, Caucasian and Asian patients presented with a much higher prevalence of palatal abnormalities, and conversely those with nested deletions presented with a much lower rate of palatal defects. Overall, 26.9% of patients underwent palatal surgery, and the most common indication was velopharyngeal dysfunction. Palatal abnormalities are a hallmark feature of 22q11.2 Deletion Syndrome; understanding the incidence, presenting features, and treatment protocols are essential for practitioners counseling and treating families affected with this disorder.
Identification of novel pathogenic variants and features in patients with pseudohypoparathyroidism and acrodysostosis, subtypes of the newly classified inactivating PTH/PTHrP signaling disorders
Authors: Truelove Adam , Mulay Akhilesh , Prapa Matina , Casey Ruth T. , Adler Amanda I. , Offiah Amaka C. , Poole Kenneth E. S. , Trotman Jamie , Al Hasso Namir , Park Soo‐Mi 
Published: May 2019

AbstractAlbright hereditary osteodystrophy (AHO) is a complex disorder defined by the presence of a short adult stature relative to the height of an unaffected parent and brachydactyly type E, as well as a stocky build, round face, and ectopic calcifications. AHO and pseudohypoparathyroidism (PHP) have been used interchangeably in the past. The term PHP describes end‐organ resistance to parathyroid hormone (PTH), occurring with or without the physical features of AHO. Conversely, pseudopseudohypoparathyroidism (PPHP) describes individuals with AHO features in the absence of PTH resistance. PHP and PPHP are etiologically linked and caused by genetic and/or epigenetic alterations in the guanine nucleotide‐binding protein alpha‐stimulating (Gsα) locus (GNAS) in chromosome 20q13. Another less‐recognized group of skeletal dysplasias, termed acrodysostosis, partially overlap with skeletal, endocrine, and neurodevelopmental features of AHO/PHP and can be overlooked in clinical practice, causing confusion in the literature. Acrodysostosis is caused by defects in two genes, PRKAR1A and PDE4D, both encoding important components of the Gsα‐cyclic adenosine monophosphate‐protein kinase A signaling pathway. We describe the clinical course and genotype of two adult patients with overlapping AHO features who harbored novel pathogenic variants in GNAS (c.2273C > G, p.Pro758Arg, NM_080425.2) and PRKAR1A (c.803C > T, p.Ala268Val, NM_002734.4), respectively. We highlight the value of expert radiological opinion and molecular testing in establishing correct diagnoses and discuss phenotypic features of our patients, including the first description of subcutaneous ossification and spina bifida occulta in PRKAR1A‐related acrodysostosis, in the context of the novel inactivating PTH/PTH related peptide signaling disorder classification system.
Middle ear pneumatization in nonhuman primates: A comparative analysis
Authors: Bernardi Margot , Couette Sébastien , Chateau Smith Carmela , Montuire Sophie 
Published: May 2019

AbstractObjectivesWe test the effects of body mass and phylogeny on middle ear cavity pneumatization, and the role of pneumatization in hearing function, spanning the anatomical, ecological, and behavioral diversity of nonhuman primates.Materials and methodsAll cavities were segmented in middle ear scans of 96 specimens, from 12 strepsirrhine and 15 haplorhine extant species. We measured the tympanic cavity (TC) separately, and all other middle ear spaces together (MES), calculating the degree of pneumatization with the surface area‐to‐volume ratio. We tested body mass effect with linear regression; we evaluated the phylogenetic signal and selection patterns, using a Kappa statistic test, and Ornstein‐Uhlenbeck models (OU). We investigated the link between pneumatization and hearing sensitivity using phylogenetic regression.ResultsTesting body mass reveals an allometric pattern for both TC and MES dimensions. Degree of pneumatization in MES is dependent on body mass in haplorhines: larger animals have more pneumatized MES. Differences at various taxonomic ranks were observed for MES, while no phylogenetic influence was observed for TC. Infraorder selection patterns are different. Auditory performance is significantly related to degree of pneumatization, indicating that a pneumatized middle ear is associated with better perception of low frequencies.DiscussionPneumatization in MES is under differential selective pressure, indicating several optima for this trait. Pneumatization in MES probably modifies hearing sensitivity through pressure regulation mechanisms, auditory bulla size reduction, and frequency modulation. This could explain strepsirrhine adaptation to high‐frequency perception, while haplorhine auditory perception is adapted to a broader sound range, including high and low frequencies.
Effect of temperature on tensile and creep‐recovery properties of braided polyester harness cord
Authors: Xie Kaifang , Shen Hua , Xu Guangbiao 
Published: May 2019

ABSTRACTTensile and creep‐recovery properties of braided polyester (PET) harness cord under various temperature and tension were studied by using an Instron universal tester. The study reveals that the tensile properties are highly related to the temperature, with a decrease of 29.6, 50.0, and 33.8% in initial modulus, yield force, and breaking force (BF), respectively, as increasing the temperature from 25 to 100 °C. Under the condition of 5% BF, the creep and recovery strain of harness cord increased by 185.7 and 353.8% separately, when the temperature increased from 40 to 100 °C, indicating the significant effect of temperature and tension on the creep‐recovery properties. The similar tendencies were also observed under the conditions of 10 and 15% BF. These results could be well described by Burgers four‐element model. During the 1.5 h creep test, only instant elastic and retarded elastic deformation could be observed and accounting for 56.1–84.3% and 15.2–43.4% of the total creep deformation, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47864.
Extending the working life of toluene diisocyanate‐based polyurethanes
Authors: Reardon Sean , Carroll Anna L. , Dumont Joseph H. , Park Chi Hoon , Lee Kwan‐Soo , Labouriau Andrea 
Published: May 2019

ABSTRACTThis work demonstrates that the addition of tridecanoic acid to a toluene diisocyante (TDI)‐based polyurethane considerable increases its working life. Formulations with the additive exhibited little changes in chemistry, glass‐transition temperatures, and thermal stability as determined by Fourier transform infrared spectroscopy, rheology studies, nuclear magnetic resonance, solvent swelling tests, and thermal analyses. There was a slight increase in toughness of the additive formulation associated with an increase in engineering strain and a decrease in peak engineering stress. Molecular dynamics simulations indicated that the acid forms hydrogen bonding with the OH groups from the diols, slowing down the polymerization. These studies demonstrate that tridecanoic acid can be used to extend working time of a TDI‐based polyurethane with minimal changes to physical and chemical properties when compared to the pristine polyurethane. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47865.
Self‐healing and conductivity of chitosan‐based hydrogels formed by the migration of ferric ions
Authors: Fu Beijia , Cheng Baoxiao , Bao Xiaojiong , Wang Zhengke , Shangguan Yonggang , Hu Qiaoling 
Published: May 2019

ABSTRACTThe currently reported self‐healing hydrogels have problems of low mechanical strength, single performance, and poor self‐healing efficiency, which greatly limit their applications. Here, through adding N‐carboxyethyl chitosan to acrylic‐Fe3+ system, the self‐healing physically crosslinked hydrogels were prepared via in situ free radical polymerization, which have excellent self‐healing ability and mechanical properties. The maximum tensile strength and elongation at break of the hydrogels can reach up to 280 KPa and 1900%, respectively. Owing to the reversibility of coordination, self‐healing efficiency of the hydrogels can reach 98% in 2.5 h. Moreover, the hydrogels also have good conductivity due to the migration of Fe3+. This strategy can broaden the applications of chitosan‐based self‐healing hydrogels. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47885.
Recycling of thermoplastic polystyrene waste using citrus peel extract for oil spill remediation
Authors: Yadav Shital , Mattaparthi Srinadh , Sreenivasulu Kuncham , Khandelwal Mudrika , Majumdar Saptarshi , Sharma Chandra Shekhar 
Published: May 2019

ABSTRACTIn this work, we report a low‐cost, less energy intensive, and an innovative way of recycling thermoplastic polystyrene (PS) waste objects into submicron, aligned fibers using extract from citrus peel, an agricultural waste. As‐fabricated recycled PS fabric is then structurally characterized and tested as an oil sorbent material. The hydrophobic‐oleophilic PS fabric is found to absorb 40.5 ± 3.6 g/g of oil, with 77.3% oil retention within 1 h. To investigate the practical application of recycled PS fabric for oil spills remediation, we tested its buoyancy properties in oil‐over‐water static and dynamic system besides examining their reusability. The as‐fabricated fabric floats on water after oil sorption indicating its high buoyancy and therefore can be collected easily after soaking the oil. This work is a simple illustration of systematic analysis of recycling two different waste materials (thermoplastic polystyrene and citrus peels) and reusing them into a more valuable product. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47886.
Synthesis of a polyethylene glycolylated polysiloxane system through a two‐step procedure and its compatibility
Authors: Liang Hongping , Tang Zilun , Feng Minghui , Wu Jianyu , Lin Wenjing , Zu Xihong , Zhang Jie , Gu Yuxin , Yi Guobin 
Published: May 2019

ABSTRACTAcrylic macromonomer was synthesized by esterification of acrylic acid (AA) and PEGylated siloxane alcohol. And the acrylic macromonomer was employed as unsaturated precursor for the hydrosilylation with polymethylhydrosiloxane (PMHS). FTIR,1H,13C,29Si‐NMR, and TGA proved that PEGylated polysiloxane was successfully synthesized. The morphological studies revealed that the dimples in the cross sections were attributed to polyethylene glycol (PEG) phase domains with diameters of 5–15 μm. The contribution of polar and dispersion factor toward surface energy was studied by contact angle (CA) measurement. The results showed that wetting behavior could transform from hydrophobic to hydrophilic with the CA from 122° to 54°. The final PEGylated polysiloxane provided sufficient compatibility and good wetting behavior, in contrast with silane ethers or alkyl silanes, indicating that it might be utilized as an alternate candidate for personal care. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47889.
Micro‐/Nanomachines Driven by Ultrasonic Power Sources
Authors: Lu Xiaolong , Shen Hui , Zhao Kangdong , Wang Zhiwen , Peng Hanmin , Liu Wenjuan 
Published: May 2019

AbstractAutonomous micro‐/nanomachines that can convert diverse energy sources into effective locomotion under the constraint of low Reynolds numbers hold considerable promise for a variety of applications, such as cargo delivery, localized biosensing, nanosurgery, and detoxification. In this Minireview, we briefly overview recent advances in the development of micro‐/nanomachines that are specifically powered by ultrasound, in particular new concept design, their working principles, and their fabrication and manipulation strategies. Finally, the exclusive biocompatibility and sustainability of ultrasound‐powered micro‐/nanomachines, as well as the critical challenges that face their in vivo application, are discussed to provide insight for the next phase of micro‐/nanomachines with versatile functionalities and enhanced capabilities.