bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and Antitrypanosomal Activity of 1,4‐Disubstituted Triazole Compounds Based on a 2‐Nitroimidazole Scaffold: a Structure‐Activity Relationship Study
Authors: Assunção Elvis L. F. , Carvalho Diego B. , das Neves Amarith R. , Kawasoko Shiguemotto Cristiane Y. , Portapilla Gisele B. , de Albuquerque Sergio , Baroni Adriano C. M. 
Published: July 2020

AbstractChagas disease affects 6–8 million people worldwide, remaining a public health concern. Toxicity, several adverse effects and inefficiency in the chronic stage of the disease are the major challenges regarding the available treatment protocols. This work involved the synthesis of twenty‐two 1,4‐disubstituted‐1,2,3‐triazole analogues of benznidazole (BZN), by using a click chemistry strategy. Analogues were obtained in moderate to good yields (40‐97 %). Antitrypanosomal activity was evaluated against the amastigote forms of Trypanosoma cruzi. Compound 8 a (4‐(2‐nitro‐1H‐imidazol‐1‐yl)methyl)‐1‐phenyl‐1H‐1,2,3‐triazole) without substituents on phenyl ring showed similar biological activity to BZN (IC50=3.0 μM, SI>65.3), with an IC50=3.1 μM and SI>64.5. Compound 8 o (3,4‐di‐OCH3−Ph) with IC50 = 0.65 μM was five‐fold more active than BZN, and showed an excellent selectivity index (SI>307.7). Compound 8 v (3‐NO2, 4‐CH3−Ph) with IC50=1.2 μM and relevant SI>166.7, also exhibited higher activity than BZN. SAR analysis exhibited a pattern regarding antitrypanosomal activity relative to BZN, in compounds with electron‐withdrawing groups (Hammett σ+) at position 3, and electron‐donating groups (Hammett σ‐) at position 4, as observed in 8 o and 8 v. Further research might explore in vivo antitrypanosomal activity of promising analogues 8 a, 8 o, and 8 v. Overall, this study indicates that approaches such as the bioisosteric replacement of amide group by 1,2,3‐triazole ring, the use of click chemistry as a synthesis strategy, and design tools like Craig‐plot and Topliss tree are promising alternatives to drug discovery.
An Aminopyridinium Ionic Liquid: A Simple and Effective Bifunctional Organocatalyst for Carbonate Synthesis from Carbon Dioxide and Epoxides
Authors: Ebrahimi Amirhossein , Rezazadeh Mostafa , Khosravi Hormoz , Rostami Ali , Al‐Harrasi Ahmed 
Published: July 2020

AbstractAn aminopyridinium ionic liquid is presented as a green, tunable, and active metal‐free one‐component catalytic system for the atom‐efficient transformation of oxiranes and CO2 to cyclic carbonates. Inclusion of a positively charged moiety into aminopyridines, through a simple single‐step synthesis, provides a one‐component ionic liquid catalytic system with superior activity; effective in ring opening of epoxide, CO2 inclusion, and stabilization of oxoanionic intermediates. An efficiency assessment of a variety of positively charged aminopyridines was pursued, and the impact of temperature, catalyst loading, and the kind of nucleophile on the catalytic performance was also investigated. Under solvent‐free conditions, this bifunctional organocatalytic system was used for the preparation of 18 examples of cyclic carbonates from a broad range of alkyl‐ and aryl‐substituted oxiranes and CO2, where up to 98 % yield and high selectivity were achieved. DFT calculations validated a mechanism in which nucleophilic ring‐opening and CO2 inclusion occur simultaneously towards cyclic carbonate formation.
Photochemistry of a 9‐Dithianyl‐Pyronin Derivative: A Cornucopia of Reaction Intermediates Lead to Common Photoproducts
Authors: Martínek Marek , Váňa Jiří , Šebej Peter , Navrátil Rafael , Slanina Tomáš , Ludvíková Lucie , Roithová Jana , Klán Petr 
Published: July 2020

AbstractLeaving groups attached to the meso‐methyl position of many common dyes, such as xanthene, BODIPY, or pyronin derivatives, can be liberated upon irradiation with visible light. However, the course of phototransformations of such photoactivatable systems can be quite complex and the identification of reaction intermediates or even products is often neglected. This paper exemplifies the photochemistry of a 9‐dithianyl‐pyronin derivative, which undergoes an oxidative transformation at the meso‐position to give a 3,6‐diamino‐9H‐xanthen‐9‐one derivative, formic acid, and carbon monoxide as the main photoproducts. The course of this multi‐photon multi‐step reaction was studied under various conditions by steady‐state and time‐resolved optical spectroscopy, mass spectrometry and NMR spectroscopy to understand the effects of solvents and molecular oxygen on individual steps. Our analyses have revealed the existence of many intermediates and their interrelationships to provide a complete picture of the transformation, which can bring new inputs to a rational design of new photoactivatable pyronin or xanthene derivatives.
“Studies of the Uptake of Nitrate in Barley. I. Kinetics of 13NO3− Influx” by M.Y. Siddiqi, A.D.M. Glass, T.J. Ruth, and T.W. Rufty, Jr., Plant Physiology (1990) 93:1426–1432
Authors: Sinclair Thomas R. 
Published: July 2020

AbstractThis article is part of a series of brief commentaries to highlight papers that have resulted in important and distinctly new perspectives in crop science. A criterion for selection of papers is that they must have been published at least 20 yr ago to allow for a long‐range perspective in assessment of the papers. The current article briefly reviews the paper by M.Y. Siddiqi, A.D.M. Glass, T.J. Ruth, and T.W. Rufty, Jr. published in 1990 that investigated the kinetics of nitrate influx by barley (Hordeum vulgare L.) seedlings. Using 13NO3−, they documented the existence of two influx systems. One was inducible and nitrate influx saturated under low nitrate concentrations. The second was noninducible and expressed a linear increase in nitrate influx over high nitrate concentrations. Key transformative results from this study were the demonstration that both systems were under negative feedback control based on root nitrate concentration.
Theoretical Insights into the Effect of Cations, Anions, and Water on Fixation of CO2 Catalyzed by Different Ionic Liquids
Authors: Xia Yangfeng , Zhang Yanqiang , Su Qian , Dong Kun 
Published: July 2020

AbstractChemical fixation of CO2 is an efficient means for decreasing amount of CO2 in the atmosphere. One of promising technologies is the cycloaddition of CO2 with epoxides to synthesize cyclic carbonates. In this reaction, ionic liquid (IL) catalysts show versatile and unique advantages. However, the reaction mechanism using ILs is not clear. In this work, a detailed theoretical investigation was performed by DFT calculations. The energetic profile shows that the reaction consists of three steps, with the ring‐opening step being the rate‐determining step. Based on the results, effects of cations, anions and water were calculated. Cations show strong hydrogen bonding interactions with epoxides, which decreases the energy barrier of the ring‐opening step, indicating that hydrogen bonds play a positive role in promoting the reaction. The effect of anions was evaluated by nucleophilicity index (NNu); anions with a larger NNu (stronger nucleophilicity) value show lower energy barriers. The influence of water was investigated by implicit and explicit models. Compared with the solvent‐free case, water as an implicit solvent decreases the energy barriers through polarization with epoxides. In the explicit solvent model, the water molecules form new hydrogen bonds with epoxides and cations, which can efficiently reduce the energy barriers. The result indicates that there is a new synergic catalytic mechanism, in which the water acts not only as solvent but also as a catalyst in the reaction. Supporting experiments further confirm the calculation results.
Data dissemination with interoperability in IoT network
Authors: Rathanasalam Radhika , Kanagasabai Kulothungan 
Published: July 2020

SummaryInternet of Things (IoT) is connected to heterogeneous devices. Efficient adaptive scheduling with encoding and decoding of data is an unaddressed issue in IoT. This paper processes the data under three major hierarchy: namely, adaptability, scheduling of data, and network coding for that data. The reliable access to the information is ensured by a device which is a primary eminence in IoT. Device must be able to adapt itself according to the changes in the network and to maintain its reliability as well as transparency and seamless access to the resources. To enhance the performance of the data dissemination, the scheduling process is investigated using the spatial grouping in IoT devices; this is achieved by joint spatial and code domain scheduling scheme, and the novel preconfigured access scheme is coined in order to minimize the collision rate of arbitrary access; during the data dissemination, the erasure coding scheme is used for the encoding and decoding of packets which provides optimal redundancy. We carried the simulation using Contiki and it shows the proposed Polymorphic Erasure Coding with Markov decision Adaptability and Neural networks (PECMAN) improves in terms of cost, overhead, and delay when compared with Multi‐user Shared Access (EMUSA), Polynomial‐time Optimal Storage Allocation (OSA) scheme, and Event‐Aware Back pressure Scheduling Scheme (EABS).
Applying computational modeling to assess age‐, sex‐, and strategy‐related differences in Spin the Pots, a working memory task for 2‐ to 4‐year‐olds
Authors: Zimmermann Laura , Frank Hannah E. , Subiaul Francys , Barr Rachel 
Published: July 2020

AbstractWorking memory (WM) develops rapidly during early childhood. In the present study, visual WM (VSM) was measured using the well‐established Spin the Pots task (Hughes & Ensor, 2005), a complex non‐verbal eight‐location object occlusion task. A self‐ordered hiding procedure was adopted to allow for an examination of children's strategy use during a VWM task. Participants (N = 640) between the ages of 2 and 4 years were tested under semi‐naturalistic conditions, in the home or in a museum. Computational modeling was used to estimate an expected value for the total trials to complete Spin the Pots via a random search and child performance was compared to expected values. Based on this approach, we determined that children who found six stickers retrieved them in significantly fewer trials than the expected value, excluding chance performance and implicating VWM. Results also showed age‐related and sex‐related changes in VWM. Between 2 and 4 years of age, 4‐year‐olds performed significantly better than younger children and girls out‐performed the boys. Spontaneous use of a color matching hiding strategy was associated with a higher success rate on the task. Implications of these findings for early development of VWM are discussed.
Don’t judge toxic weeds on whether they are native but on their ecological effects
Authors: Zhang Zhenchao , Sun Jian , Liu Miao , Xu Ming , Wang Yi , Wu Gao‐lin , Zhou Huakun , Ye Chongchong , Tsechoe Dorji , Wei Tianxing 
Published: July 2020

AbstractThe sharp rise in anthropogenic activities and climate change has caused the extensive degradation of grasslands worldwide, jeopardizing ecosystem function, and threatening human well‐being. Toxic weeds have been constantly spreading in recent decades; indeed, their occurrence is considered to provide an early sign of land degeneration. Policymakers and scientific researchers often focus on the negative effects of toxic weeds, such as how they inhibit forage growth, kill livestock, and cause economic losses. However, toxic weeds can have several potentially positive ecological impacts on grasslands, such as promoting soil and water conservation, improving nutrient cycling and biodiversity conservation, and protecting pastures from excessive damage by livestock. We reviewed the literature to detail the adaptive mechanisms underlying toxic weeds and to provide new insight into their roles in degraded grassland ecosystems. The findings highlight that the establishment of toxic weeds may provide a self‐protective strategy of degenerated pastures that do not require special interventions. Consequently, policymakers, managers, and other personnel responsible for managing grasslands need to take appropriate actions to assess the long‐term trade‐offs between the development of animal husbandry and the maintenance of ecological services provided by grasslands.
A High‐sensitivity and Enzyme‐free Clenbuterol Sensor using SWCNT Arrays Prepared with a One‐pot Method Comprising Gold Nanoparticles and Cl−
Authors: Chen Baitao , Liu Jia , Li Shasha , Ren Yuanhui , Yuan Yi , Zhu Hong , Li Hongna 
Published: July 2020

AbstractWe describe a novel enzyme‐free sensor for clenbuterol (CLE) prepared by a simple electrochemical method. A new method to detect clenbuterol hydrochloride was developed by single‐walled carbon nanotubes (SWCNTs) arrays and gold nanoparticles (AuNPs)‐Cl− complex. SWCNT arrays modified glass carbon electrode (GCE) was first prepared by one‐pot method with cyclic voltammetry.Then AuNPs were deposited on the SWCNT arrays and complexed with a high concentration of chloride ions (0.1 mol/L). The as‐fabricated SWCNT arrays/AuNPs senor have showed an excellent sensitivity in CLE detection with lower detection limit (0.5 ng/L) and wider linear range (1–800 ng/L). Its high performance can be attributed to the high catalytic activity of SWCNT arrays and the special absorption of CLE on AuNPs. The surface morphology of the electrode was analyzed by atomic force microscopy, X‐ray photoelectron spectroscopy and SEM. This work offers a new method for the synthesis of SWCNT arrays and a novel avenue for CLE detection. The modified electrode was stable with 98.5 % of its initial current response after remained one month, it was used to detect CLE in human urine, animal tissues and food with satisfactory results.
The autism diagnostic observation schedule: Patterns in individuals with anorexia nervosa
Authors: Bentz Mette , Westwood Heather , Jepsen Jens Richardt Møllegaard , Plessen Kerstin Jessica , Tchanturia Kate 
Published: July 2020

AbstractObjectiveStudies have used the Autism Diagnostic Observation Schedule (the ADOS‐2) in individuals with anorexia nervosa (AN), but the patterns of scores have not been assessed. We examined which subset of the ADOS‐2 items best discriminate individuals with AN from healthy controls (HC), and assessed the potential clustering of AN participants based on different profiles of the ADOS‐2 item scores.MethodWe combined datasets from two previous studies, and (a) compared mean ranks between young AN participants (N = 118) and HC (N = 42), (ii) replicated the item selection procedure of the existing ADOS‐2 algorithm to assess sensitivity of items in the AN group, and (c) applied a two‐step clustering analysis in the AN group (N = 149).ResultsAN participants displayed significantly higher mean ranks than HC participants in five of 32 items. All five items are part of the existing ADOS‐2 algorithm. We found two clusters of AN participants; one representing normal social behaviour, comprising 68% of the individuals with AN, and one representing less efficient social behaviour, comprising 32% of individuals with AN.ConclusionsThe items comprising the social affective cluster of the existing ADOS‐2 algorithm are well suited to assess difficulties with social functioning in individuals with AN.
Stock‐induced Google trends and the predictability of sectoral stock returns
Authors: Salisu Afees A. , Ogbonna Ahamuefula E. , Adediran Idris 
Published: July 2020

AbstractIn this paper, we consider Google trends (G‐trends) as a measure of investors' attention in the predictability of stock returns across eleven major US sectors. The theoretical motivation for our paper is clear. In seeking information to guide investment decisions, investors' sentiments are shaped by news such as G‐trends that could induce changes in the prices of stocks. Thus, we construct a predictive model that incorporates G‐trends series as a predictor of stock returns and thereafter we account for evident asymmetry in G‐trends to analyze the signficance of positive‐ and negative‐worded news in the predictability of stock returns. We also compare single‐ and multi‐factor predictive models augmented with distinctive statistical effects against the baseline time series model. We highlight three key findings: (1) G‐trends record consistent negative correlations with stock returns across sectors. (2) The proposed predictive model with G‐trends outperforms the baseline (random walk) model. (3) The inclusion of asymmetry and macroeconomic variables improves the outperformance of G‐trends over the baseline model.
Evaluation of the efficacy of pimavanserin in the treatment of agitation and aggression in patients with Alzheimer's disease psychosis: A post hoc analysis
Authors: Ballard Clive G. , Coate Bruce , Abler Victor , Stankovic Srdjan , Foff Erin 
Published: July 2020

ObjectivesPatients with Alzheimer's disease psychosis (ADP) commonly experience concomitant agitation and aggression. We investigated whether a reduction in ADP following pimavanserin treatment conferred a reduction in associated agitation and aggression.MethodsACP‐103‐019 was a 12‐week, randomized, double‐blind, placebo‐controlled study that evaluated the efficacy of pimavanserin (34 mg) in reducing psychotic symptoms in patients with ADP. The primary endpoint was change from baseline in Neuropsychiatric Inventory‐Nursing Home Version‐Psychosis Score (NPI‐NH‐PS) at week six. A post hoc analysis examined whether there was a greater reduction in agitation and aggression (NPI‐NH domain C [agitation/aggression] and Cohen‐Mansfield Agitation Inventory‐Short Form [CMAI‐SF]) in pimavanserin‐treated patients who experienced a reduction of hallucinations and delusions (psychosis responders defined as ≥50% reduction from baseline in NPI‐NH‐PS, week six) when compared with those who did not (nonresponders).ResultsPimavanserin‐treated patients with ≥50% response in psychotic symptoms (n = 44) showed a greater improvement in agitation and aggression symptoms on the NPI‐NH domain C (week six, least squares mean [LSM] difference = −3.64, t = −4.69, P < .0001) and the CMAI‐SF (week six, LSM difference = −3.71, t = −2.01, P = .0483) than nonresponders (n = 32). Differences between psychosis responders and nonresponders were also observed in patients with more severe agitation and aggression at baseline on the NPI‐NH domain C (responders, n = 26; nonresponders, n = 13; week six, LSM difference = −3.03, t = −2.44, P = .019).ConclusionsPatients with ADP, who show improvement in psychotic symptoms after pimavanserin treatment, also experience an improvement in concomitant agitation and aggression.
Can we predict real‐time fMRI neurofeedback learning success from pretraining brain activity?
Authors: Haugg Amelie , Sladky Ronald , Skouras Stavros , McDonald Amalia , Craddock Cameron , Kirschner Matthias , Herdener Marcus , Koush Yury , Papoutsi Marina , Keynan Jackob N. , Hendler Talma , Cohen Kadosh Kathrin , Zich Catharina , MacInnes Jeff , Adcock R. Alison , Dickerson Kathryn , Chen Nan‐Kuei , Young Kymberly , Bodurka Jerzy , Yao Shuxia , Becker Benjamin , Auer Tibor , Schweizer Renate , Pamplona Gustavo , Emmert Kirsten , Haller Sven , Van De Ville Dimitri , Blefari Maria‐Laura , Kim Dong‐Youl , Lee Jong‐Hwan , Marins Theo , Fukuda Megumi , Sorger Bettina , Kamp Tabea , Liew Sook‐Lei , Veit Ralf , Spetter Maartje , Weiskopf Nikolaus , Scharnowski Frank 
Published: July 2020

AbstractNeurofeedback training has been shown to influence behavior in healthy participants as well as to alleviate clinical symptoms in neurological, psychosomatic, and psychiatric patient populations. However, many real‐time fMRI neurofeedback studies report large inter‐individual differences in learning success. The factors that cause this vast variability between participants remain unknown and their identification could enhance treatment success. Thus, here we employed a meta‐analytic approach including data from 24 different neurofeedback studies with a total of 401 participants, including 140 patients, to determine whether levels of activity in target brain regions during pretraining functional localizer or no‐feedback runs (i.e., self‐regulation in the absence of neurofeedback) could predict neurofeedback learning success. We observed a slightly positive correlation between pretraining activity levels during a functional localizer run and neurofeedback learning success, but we were not able to identify common brain‐based success predictors across our diverse cohort of studies. Therefore, advances need to be made in finding robust models and measures of general neurofeedback learning, and in increasing the current study database to allow for investigating further factors that might influence neurofeedback learning.
Do intrinsic brain functional networks predict working memory from childhood to adulthood?
Authors: Zhang Han , Hao Shuji , Lee Annie , Eickhoff Simon B. , Pecheva Diliana , Cai Shirong , Meaney Michael , Chong Yap‐Seng , Broekman Birit F. P. , Fortier Marielle V. , Qiu Anqi 
Published: July 2020

AbstractWorking memory (WM) is defined as the ability to maintain a representation online to guide goal‐directed behavior. Its capacity in early childhood predicts academic achievements in late childhood and its deficits are found in various neurodevelopmental disorders. We employed resting‐state fMRI (rs‐fMRI) of 468 participants aged from 4 to 55 years and connectome‐based predictive modeling (CPM) to explore the potential predictive power of intrinsic functional networks to WM in preschoolers, early and late school‐age children, adolescents, and adults. We defined intrinsic functional networks among brain regions identified by activation likelihood estimation (ALE) meta‐analysis on existing WM functional studies (ALE‐based intrinsic functional networks) and intrinsic functional networks generated based on the whole brain (whole‐brain intrinsic functional networks). We employed the CPM on these networks to predict WM in each age group. The CPM using the ALE‐based and whole‐brain intrinsic functional networks predicted WM of individual adults, while the prediction power of the ALE‐based intrinsic functional networks was superior to that of the whole‐brain intrinsic functional networks. Nevertheless, the CPM using the whole‐brain but not the ALE‐based intrinsic functional networks predicted WM in adolescents. And, the CPM using neither the ALE‐based nor whole‐brain networks predicted WM in any of the children groups. Our findings showed the trend of the prediction power of the intrinsic functional networks to cognition in individuals from early childhood to adulthood.
Multicomponent Alginate‐Derived Hydrogel Microspheres Presenting Hybrid Ionic‐Covalent Network and Drug Eluting Properties
Authors: Szabó Luca , Noverraz François , Gerber‐Lemaire Sandrine 
Published: July 2020

AbstractThe development of multifunctional encapsulation biomaterials could help the translation of cell‐based therapies into standard medical care. One of the major hurdles in the field of encapsulated cell transplantation is the current lack of materials presenting optimal properties, including long term stability, mechanical durability and non‐immunogenic character. Modification of sodium alginate (Na‐alg) with polyethylene glycol (PEG) derivatives, without restricting its gelling abilities, appeared as an efficient strategy to produce dual ionic‐covalent spherical hydrogels with enhanced mechanical performance as well as drug‐eluting microspheres (MS) for the mitigation of inflammatory response after transplantation. In this study, the combination of PEGylated alginates equipped with cross‐reactive functionalities and the anti‐inflammatory drug ketoprofen (KET) resulted in the assembly of multifunctional (MF) hybrid MS, merging the advantages of ionic‐covalent hydrogels with the ability for controlled drug delivery. Physical characterization confirmed their improved mechanical resistance, their higher shape recovery performance and increased stability toward non‐gelling ions, as compared to pure Ca‐alg hydrogels. In vitro release kinetics revealed the controlled and sustained delivery of KET for over two weeks.