bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proline and its Derivatives as Organocatalysts for Multi‐ Component Reactions in Aqueous Media: Synergic Pathways to the Green Synthesis of Heterocycles
Authors: Vachan B. S. , Karuppasamy Muthu , Vinoth Perumal , Vivek Kumar Sundaravel , Perumal Subbu , Sridharan Vellaisamy , Menéndez J. Carlos 
Published: July 2019

AbstractProline is a non‐toxic and inexpensive natural amino acid that is readily available in both enantiomeric forms and was one of the very first compounds to be studied as an organocatalyst. Proline can engage in several modes of organocatalysis, as it can behave both as a Brønsted acid or a Brønsted base, and it can also easily generate the iminium or enamine intermediates that are typical of covalent organocatalysis. In view of the importance of diminishing the generation of residues formed by volatile organic solvents, the development of synthetically useful reactions that can be performed in aqueous environments is of increasing significance. The synergic combination of the advantages of water as a reaction medium with the efficiency associated to reactions that are able to generate several bonds in one operation is particularly relevant from the point of view of sustainable chemistry. In this review we critically summarize the use of proline and proline derivatives as catalysts of multi‐component reactions performed in aqueous media and leading to synthetically and biologically relevant heterocycles, a very important class of compounds that constitutes over 60% of drugs and agrochemicals.magnified image
Indocyanine Green–Coated Gold Nanoclusters for Photoacoustic Imaging and Photothermal Therapy
Authors: Higbee‐Dempsey Elizabeth , Amirshaghaghi Ahmad , Case Matthew J. , Miller Joann , Busch Theresa M. , Tsourkas Andrew 
Published: July 2019

AbstractTraditional oncology treatment modalities are often associated with a poor therapeutic index. This has driven the development of new targeted treatment modalities, including several based on the conversion of optical light into heat energy (photothermal therapy, PTT) and sound waves (photoacoustic imaging, PA) that can be applied locally. These approaches are especially effective when combined with photoactive nanoparticles that preferentially accumulate in tissues of interest and thereby further increase spatiotemporal resolution. In this study, two clinically used materials that have proven effective in both PTT and PA—indocyanine green (ICG) and gold nanoparticles (AuNPs)—are combined into a single nanoformulation. These particles, “ICG–AuNP clusters,” incorporate high concentrations of both moieties without the need for additional stabilizing or solubilizing reagents. The clusters demonstrate high theranostic efficacy both in vitro and in vivo, compared with ICG alone. Specifically, in an orthotopic mouse model of triple‐negative breast cancer, ICG–AuNP clusters can be injected intravenously, imaged in the tumor by PA, and then combined with near‐infrared laser irradiation to successfully thermally ablate tumors and prolong animal survival. Altogether, this novel nanomaterial demonstrates excellent therapeutic potential for integrated treatment and imaging.
Graphitic Carbon Nitride with Dopant Induced Charge Localization for Enhanced Photoreduction of CO2 to CH4
Authors: Fu Junwei , Liu Kang , Jiang Kexin , Li Huangjingwei , An Pengda , Li Wenzhang , Zhang Ning , Li Hongmei , Xu Xiaowen , Zhou Haiqing , Tang Dongsheng , Wang Xiaoming , Qiu Xiaoqing , Liu Min 
Published: July 2019

AbstractThe photoreduction of CO2 to hydrocarbon products has attracted much attention because it provides an avenue to directly synthesize value‐added carbon‐based fuels and feedstocks using solar energy. Among various photocatalysts, graphitic carbon nitride (g‐C3N4) has emerged as an attractive metal‐free visible‐light photocatalyst due to its advantages of earth‐abundance, nontoxicity, and stability. Unfortunately, its photocatalytic efficiency is seriously limited by charge carriers′ ready recombination and their low reaction dynamics. Modifying the local electronic structure of g‐C3N4 is predicted to be an efficient way to improve the charge transfer and reaction efficiency. Here, boron (B) is doped into the large cavity between adjacent tri‐s‐triazine units via coordination with two‐coordinated N atoms. Theoretical calculations prove that the new electron excitation from N (2px, 2py) to B (2px, 2py) with the same orbital direction in B‐doped g‐C3N4 is much easier than N (2px, 2py) to C 2pz in pure g‐C3N4, and improves the charge transfer and localization, and thus the reaction dynamics. Moreover, B atoms doping changes the adsorption of CO (intermediate), and can act as active sites for CH4 production. As a result, the optimal sample of 1%B/g‐C3N4 exhibits better selectivity for CH4 with ≈32 times higher yield than that of pure g‐C3N4.
Cu14 Cluster with Partial Cu(0) Character: Difference in Electronic Structure from Isostructural Silver Analog
Authors: Li Yan‐Ling , Wang Jie , Luo Peng , Ma Xiao‐Hong , Dong Xi‐Yan , Wang Zhao‐Yang , Du Chen‐Xia , Zang Shuang‐Quan , Mak Thomas C. W. 
Published: July 2019

AbstractAn atom‐precise Cu0‐containing copper cluster, Cu14(C2B10H10S2)6(CH3CN)8 (abbreviated as Cu14‐8CH3CN) is reported, which is synthesized via a simultaneous reduction strategy and fully characterized by single‐crystal X‐ray diffraction, ESI‐TOF‐MS, and X‐ray photoelectron spectroscopy. Cu14‐8CH3CN is the only copper cluster that has a virtually identical silver structural analog, i.e., Ag14(C2B10H10S2)6(CH3CN)8 (hereafter as Ag14‐8CH3CN). Nevertheless, density functional theory calculations reveal that the electronic structure of Cu14‐8CH3CN differs significantly from the superatom electronic configuration of Ag14‐8CH3CN. Moreover, Cu14‐8CH3CN shows room‐temperature luminescence and good electrocatalytic activities in the ethanol oxidation reaction and detection of H2O2. This pair of unprecedented analogous molecular nanoscale systems offer an ideal platform to investigate the fundamental differences between copper and silver in terms of catalytic activity and optical properties.
Bubble dynamics in bubbling fluidized beds of ellipsoidal particles
Authors: Shrestha Siddhartha , Kuang Shibo , Yu Aibing , Zhou Zongyan 
Published: July 2019

AbstractThis article presents a CFD‐DEM study on the effect of particle shape on bubble dynamics in bubbling fluidized beds. The particles used are ellipsoids, covering from disk‐type to cylinder‐type. The phenomena such as bubble coalescence and splitting are successfully generated, and the results are compared with literature, showing a good agreement. The results demonstrate that the bubble forming/rising regions and patterns are influenced significantly by particle shape. Ellipsoidal particles have asymmetrical bubble patterns with two or more circulation vortices while the bubbles for spherical particles form at the bed centerline and rise through the center of the bed. Hence, the vertical mass flux at the bed centerline for spheres is always positive, and ellipsoids have negative or positive vertical mass fluxes. The solid mixing estimated based on the dispersion coefficient revealed poor mixing for ellipsoids. Spherical particles have a larger bubble size and higher bubble rising velocity than ellipsoids.
Woodhouse–Sakati Syndrome: First report of a Portuguese case
Authors: Louro Pedro , Durães João , Oliveira Diana , Paiva Sandra , Ramos Lina , Macário Maria Carmo 
Published: July 2019

AbstractWoodhouse–Sakati Syndrome is a very rare autosomal recessive disorder caused by pathogenic variants in the DCAF17 gene, which encodes DDB1‐ and CUL4‐associated factor 17. It is a multisystemic disorder characterized by hypogonadism, adolescent‐ to young adult‐onset diabetes mellitus, hypothyroidism, and alopecia. Neurologic involvement includes childhood‐onset moderate bilateral sensorineural hearing loss, mild intellectual disability adolescent‐ to young adult‐onset of extrapyramidal findings, dysarthria, and dysphagia. Brain imaging typically reveals iron deposition in the globus pallidus and periventricular leukodystrophy. We report the case of a 31‐year‐old Portuguese female, the only child of a consanguineous couple. She presented with cognitive impairment, spastic paraparesis, lower limb dystonia, dysarthria, and dysphagia. She also had hypergonadotrophic hypogonadism associated with primary amenorrhea, insulin‐dependent diabetes mellitus with retinopathy, primary hypothyroidism, moderate bilateral sensorineural hearing loss, and alopecia. Serial brain magnetic resonance imaging showed a progressive periventricular leukodystrophy with pontine involvement and significant bilateral iron deposition in the globus pallidus, substantia nigra, and red nucleus. The diagnosis of Woodhouse–Sakati Syndrome was eventually proposed and DCAF17 gene sequencing identified a novel likely pathogenic homozygous variant NG_013038.1(NM_025000.3):c.1091+2T>C. Genetic testing allowed a more accurate prognosis and a precise genetic counseling for our patient's family.
Prostate‐Specific Membrane Antigen (PSMA)‐Targeted Radionuclide Probes for Imaging and Therapy of Prostate Cancer
Authors: Kwon Hongmok , Son Sang‐Hyun , Byun Youngjoo 
Published: July 2019

AbstractProstate cancer (PCa) is one of the common cancers among men. Despite the prevalence of PCa, there are still unmet medical needs in the diagnosis and treatment of metastatic prostate cancer. Prostate‐specific membrane antigen (PSMA) is a type II zinc‐dependent metalloprotease which is highly overexpressed in metastatic PCa. In the last several years, PCa imaging probes targeting PSMA have been developed in academia as well as in industry. Among them, low molecular weight PSMA‐targeted ligands based on the Glu‐urea‐Lys scaffold have been evaluated in preclinical and clinical studies. This review provides an overview of the recent development in PSMA‐targeted imaging or therapeutic probes for metastatic PCa.
Future manufacturing and remanufacturing of polymeric materials
Authors: Schork F. Joseph 
Published: July 2019

AbstractThis paper will attempt to describe the future of manufacturing technology in polymeric products. While a wide range of literature references are cited to illustrate the technologies discussed, it is not meant to be a literature review of such a wide field, but rather as an educated guess about where polymer manufacturing (and remanufacturing) will evolve in the foreseeable future.
Effects of stick–slip transition on polymer melt apparent shear viscosity measurement
Authors: Zhang Yinglan , Song Xiaoping , Kan Ying , Huang Mengmeng , Shi Cuijie , Dai Xiaoping , Zhang Zhengdong 
Published: July 2019

ABSTRACTA twin‐bore capillary rheometer is used for the apparent shear viscosity measurement of commercial polyolefin melts based on Ostwald‐de Waele model. The effects of stick–slip transition of linear low‐density polyethylene (LLDPE) and high‐density polyethylene (HDPE) are investigated. The maximum error of apparent shear viscosity calculated by corrected shear rate is 23% when the stick–slip transition occurs. Based on the entanglement‑disentanglement theory, a schematic diagram for shear stress curve containing stick–slip transition is presented to illustrate polymer melt flow in capillary. In this study, the critical stress at the beginning of stick–slip transition at 220 °C is 23.01 kPa higher than that at 190 °C, and why it increases with increasing temperature is discussed with a molecular mechanism in combination with entropy elasticity and entanglement‑disentanglement theory. Through the analysis of ULDPE, PS, EVA, and K‐Resin, it can be found that short branches or side groups are helpful to avoid the stick–slip transition. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 48230.
Castor oil‐based polyols with gradually increasing functionalities for biopolyurethane synthesis
Authors: Park Chang Kyu , Lee Joo Hyung , Kim Ick Soo , Kim Seong Hun 
Published: July 2019

ABSTRACTIn this research, castor oil‐based polyols with gradual increasing functionalities were prepared using thiol‐ene photo click reaction. The polyols were prepared by facile and efficient photo‐click reaction using thiols with different number of hydroxyl groups. The polyols were successfully synthesized using a modified bio‐oxygen demand (BOD) reactor and their structures were characterized. The hydroxyl number of the prepared polyols gradually increased depending on the thiol used for preparation. The increased hydroxyl number resulted in increased crosslinking densities for the prepared polyurethanes. The effect of the increasing crosslinking density and structure of the polyols on the mechanical and thermal properties of polyurethane were investigated. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48304.
Implications of nutrient enrichment for the conservation and management of seagrass Zostera muelleri meadows
Authors: Li Moyang , Lundquist Carolyn J. , Pilditch Conrad A. , Rees T.A.V. , Ellis Joanne 
Published: July 2019

Abstract

Nutrient overenrichment in aquatic environments, or eutrophication, is increasingly affecting seagrass habitats around the world, leading to the degradation of seagrass ecosystems and the loss of associated ecosystem services.
The resistance of seagrass to nutrient enrichment is believed to be site specific, yet the direct correlations between environmental factors and the resistance of seagrass meadows has not yet been adequately resolved. The response of seagrass beds to long‐term multiple‐level sediment nutrient enrichment represents a current research gap.
This study therefore assessed the in situ long‐term influence of four levels of sediment urea fertilizer addition on Zostera muelleri plants using a manipulative experimental design at three sites with diverse sediment characteristics. Specifically, this study investigated the response of porewater nutrient concentration, seagrass morphology indices, and seagrass plant tissue carbon and nitrogen contents under experimental nutrient stress levels.
Over a 13‐month experiment, sediment nutrient addition substantially increased the ammonium concentrations in the sediment porewater, significantly decreased seagrass morphology indices, and caused a carbon and nitrogen imbalance in plant tissues. Ammonium toxicity was more pronounced in seagrass meadows growing on sandy substrates with lower relative above‐ground biomass, which showed low resistance to eutrophication at sediment ammonium concentrations of up to 1 × 104 μM. Plants growing in muddy sand substrates with higher relative above‐ground biomass were more resistant to nutrient impacts, however, with a delayed negative response observed in response to higher nutrient concentrations (up to 1 × 105 μM).
Our findings suggest that seagrasses in low‐nutrient sandy environments show more rapid responses to eutrophication, although seagrasses in both sandy and muddy substrates exhibited declines in response to a long‐term elevation of sediment nutrient concentrations. While continuing to assess the relative susceptibility of seagrass habitats across differing environments to inform coastal management, conservation efforts should allocate resources accordingly and prioritize reducing nutrient overenrichment in sensitive seagrass meadows.
Imaging of Hypochlorous Acid by Fluorescence and Applications in Biological Systems
Authors: Yudhistira Tesla , Mulay Sandip V. , Kim Youngsam , Halle Mahesh B. , Churchill David G. 
Published: July 2019

AbstractIn recent decades, HOCl research has attracted a lot of scientists from around the world. This chemical species is well known as an important player in the biological systems of eukaryotic organisms including humans. In the human body, HOCl is produced by the myeloperoxidase enzyme from superoxide in very low concentrations (20 to 400 μm); this species is secreted by neutrophils and monocytes to help fight pathogens. However, in the condition called “oxidative stress”, HOCl has the capability to attack many important biomolecules such as amino acids, proteins, nucleotides, nucleic acids, carbohydrates, and lipids; these reactions could ultimately contribute to a number of diseases such as neurodegenerative diseases (AD, PD, and ALS), cardiovascular diseases, and diabetes. In this review, we discuss recent efforts by scientists to synthesize various fluorophores which are attached to receptors to detect HOCl such as: chalcogen‐based oxidation, oxidation of 4‐methoxyphenol, oxime/imine, lactone ring opening, and hydrazine. These synthetic molecules, involving rational synthetic pathways, allow us to chemoselectively target HOCl and to study the level of HOCl selectivity through emission responses. Virtually all the reports here deal with well‐defined and small synthetic molecular systems. A large number of published compounds have been reported over the past years; this growing field has given scientists new insights regarding the design of the chemosensors. Reversibility, for example is considered important from the stand point of chemosensor reuse within the biological system; facile regenerability using secondary analytes to obtain the initial probe is a very promising avenue. Another aspect which is also important is the energy of the emission wavelength of the sensor; near‐infrared (NIR) emission is favorable to prevent autofluorescence and harmful irradiation of tissue; thus, extended applicability of such sensors can be made to the mouse model or animal model to help image internal organs. In this review, we describe several well‐known types of receptors that are covalently attached to the fluorophore to detect HOCl. We also discuss the common fluorophores which are used by chemist to detect HOCl, Apart from the chemical aspects, we also discuss the capabilities of the compounds to detect HOCl in living cells as measured through confocal imaging. The growing insight from HOCl probing suggests that there is still much room for improvement regarding the available molecular designs, knowledge of interplay between analytes, biological applicability, biological targeting, and chemical switching, which can also serve to further sensor and theurapeutic agent development alike.
Pupil Dilation Progression Modulates Aberrant Social Cognition in Autism Spectrum Disorder
Authors: Bast Nico , Banaschewski Tobias , Dziobek Isabel , Brandeis Daniel , Poustka Luise , Freitag Christine M. 
Published: July 2019

Progression of pupil dilation (PD) in response to visual stimuli may indicate distinct internal processes. No study has been performed on PD progression during a social cognition task. Here, we describe PD progression during the Movie for the Assessment of Social Cognition (MASC) test in n = 23 adolescents with Autism Spectrum Disorder (ASD) and n = 24 age, IQ and sex‐matched neurotypical controls (NTC). The MASC consists of 43 video sequences depicting human social interactions, each followed by a multiple‐choice question concerning characters' mental states. PD progression data were extracted by eye tracking and controlled for fixation behavior. Segmenting PD progression during video sequences by principal component analysis, three sequential PD components were unveiled. In ASD compared with NTC, a distinct PD progression was observed with increased constriction amplitude, increased dilation latency, and increased dilation amplitude that correlated with PD progression components. These components predicted social cognition performance. The first and second PD components correlated positively with MASC behavioral performance in ASD but negatively in NTC. These PD components may be interpreted as indicators of sensory‐perceptual processing and attention function. In ASD, aberrant sensory‐perceptual processing and attention function could contribute to attenuated social cognition performance. This needs to be tested by additional studies combining the respective cognitive tests and the outlined PD progression analysis. Phasic activity of the locus coeruleus–norepinephrine system is discussed as putatively shared underlying mechanism. Autism Res2019. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.Lay SummaryIn adolescents with autism, we found an altered pupil dilation during watching scenes of human interactions. Early pupil dilation correlated positively with the number of correct answers to questions about the shown human interactions. Our findings suggest that aberrant sensory processing and attention function may contribute to altered social cognition in autism.
Altered Neural Connectivity in Females, But Not Males with Autism: Preliminary Evidence for the Female Protective Effect from a Quality‐Controlled Diffusion Tensor Imaging Study
Authors: Lei Jiedi , Lecarie Emma , Jurayj Jane , Boland Sarah , Sukhodolsky Denis G. , Ventola Pamela , Pelphrey Kevin A. , Jou Roger J. 
Published: July 2019

Previous studies using diffusion tensor imaging (DTI) to investigate white matter (WM) structural connectivity have suggested widespread, although inconsistent WM alterations in autism spectrum disorder (ASD), such as greater reductions in fractional anisotropy (FA). However, findings may lack generalizability because: (a) most have focused solely on the ASD male brain phenotype, and not sex‐differences in WM integrity; (b) many lack stringent and transparent data quality control such as controlling for head motion in analysis. This study addressed both issues by using Tract‐Based Spatial Statistics (TBSS) to separately compare WM differences in 81 ASD (56 male, 25 female; 4–21 years old) and 39 typically developing (TD; 23 males, 16 females; 5–18 years old) children and young people, carefully group‐matched on sex, age, cognitive abilities, and head motion. ASD males and females were also matched on autism symptom severity. Two independent‐raters completed a multistep scan quality assurance to remove images that were significantly distorted by motion artifacts before analysis. ASD females exhibited significant widespread reductions in FA compared to TD females, suggesting altered WM integrity. In contrast, no significant localized or widespread WM differences were found between ASD and TD males. This study highlights the importance of data quality control in DTI, and outlines important sex‐differences in WM alterations in ASD females. Future studies can explore the extent to which neural structural differences might underlie sex‐differences in ASD behavioral phenotype, and guide clinical interventions to be tailored toward the unique needs of ASD females and males. Autism Res 2019, 12: 1472–1483. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.Lay SummaryPrevious Diffusion Tensor Imaging (DTI) studies have found atypical brain structural connectivity in males with autism, although findings are inconclusive in females with autism. To investigate potential sex‐differences, we studied males and females with and without autism who showed a similar level of head movement during their brain scan. We found that females with autism had widespread atypical neural connectivity than females without autism, although not in males, highlighting sex‐differences.