bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectroscopic, thermodynamic and ultrasonic properties of pseudo‐binary mixtures of organic extractants and vegetable oil at 25–60°C under atmospheric pressure
Authors: Sarkar Soumi , Mondal Supriyo Kumar , Beriya Manoj Kumar , Saha Prabirkumar 
Published: May 2021

AbstractThis work is intended to investigate the molecular interactions and transport properties of five pseudo‐binary mixtures of various combinations of vegetable oils (sesame oil and sunflower oil) and organic extractants (Aliquat 336, TBP, D2EHPA and TOA) by determining their surface tension, density and viscosity over a temperature range of 25–60°C at atmospheric pressure. The experimental data are fitted into various literature models. Information on excess molar volume and viscosity deviation leads to an understanding of solute–solvent interactions. Further, the ultrasonic velocity, isentropic compressibility, intermolecular free length, specific impedance, apparent molar volume, volumetric thermal expansion coefficient, excess Gibbs' free energy, change in enthalpy of mixing and entropy of activation of the liquids have been calculated. A model relating the surface tension, density and viscosity of the pseudo‐binary mixtures has been proposed in this paper. Analysis of Fourier transform infrared (FTIR) studies has further illustrated the intermolecular interactions in the pseudo‐binary mixtures.
3D printing of shape memory polymers
Authors: Ehrmann Guido , Ehrmann Andrea 
Published: May 2021

AbstractShape memory polymers (SMPs) are polymers which ''remember'' their original shape and can return to it after deformation, if an external stimulus—often an increased temperature – is applied. Some SMPs can be 3D printed, typically by fused deposition modeling (FDM). The most well‐known SMP is poly(lactic acid), which belongs to the most often used materials in FDM 3D printing. There are; however, many more SMPs which can be 3D printed to combine the possibilities to prepare new, sophisticated shapes with the opportunity to restore these shapes after undesirable or intentional deformation. This review gives an overview of several 3D printable SMPs, their mechanical characteristics and their possible applications.
Estimating herbarium specimen digitization rates: Accounting for human experience
Authors: Powell Caleb , Krakowiak Alaina , Fuller Rachel , Rylander Erica , Gillespie Emily , Krosnick Shawn , Ruhfel Brad , Morris Ashley B. , Shaw Joey 
Published: April 2021

PremiseHerbaria are invaluable sources for understanding the natural world, and in recent years there has been a concerted effort to digitize these collections. To organize such efforts, a method for estimating the necessary labor is desired. This work analyzes digitization productivity reports of 105 participants from eight herbaria, deriving generalized labor estimates that account for human experience.Methods and ResultsIndividuals’ rates of digitization were grouped based on cumulative time performing each task and then used to estimate a series of generalized labor projection models. In most cases, productivity was shown to improve with experience, suggesting longer technician retention can reduce labor requirements by 20%.ConclusionsUsing student labor is a common tactic for digitization efforts, and the resulting outreach exposes future professionals to natural history collections. However, overcoming the learning curve should be considered when estimating the labor necessary to digitize a collection.
Predicting Dinitrogen Activation via Transition‐Metal‐Involved [4+2] Cycloaddition Reaction
Authors: Dong Shicheng , Zhu Jun 
Published: May 2021

AbstractAs the strongest triple bond in nature, the N≡N triple bond activation has always been a challenging project in chemistry. On the other hand, since the award of the Nobel Prize in Chemistry in 1950, the Diels‐Alder reaction has served as a powerful and widely applied tool in the synthesis of natural products and new materials. However, the application of the Diels‐Alder reaction to dinitrogen activation remains less developed. Here we first demonstrate that a transition‐metal‐involved [4+2] Diels‐Alder cycloaddition reaction could be used to activate dinitrogen without an additional reductant by density functional theory calculations. Further study reveals that such a dinitrogen activation by 1‐metalla‐1,3‐dienes screened out from a series of transition metal complexes (38 species) according to the effects of metal center, ligand, and substituents can become favorable both thermodynamically (with an exergonicity of 28.2 kcal mol−1) and kinetically (with an activation energy as low as 13.8 kcal mol−1). Our findings highlight an important application of the Diels‐Alder reaction in dinitrogen activation, inviting experimental chemists’ verification.
Pharmacokinetic comparisons of six steroid saponins in rat plasma following oral administration of crude and stir‐fried Fructus Tribuli extracts by UHPLC–MS/MS
Authors: Song Xiao , Yuan Yaohui , Wang Shuyue , Sun Xiaochen , Zhang Chao , Gao Peng , Shi Lei 
Published: May 2021

AbstractModern pharmacological studies have shown that Fructus Tribuli can improve sexual function and treat cardiovascular diseases. In this study, we focused on comparing the pharmacokinetics of crude Fructus Tribuli (CFT) and stir‐fried Fructus Tribuli (SFT) to further clarify the changes in chemical composition in vivo. The quantitation of six analytes was performed in a triple quadrupole mass spectrometer using the multiple reaction monitoring mode. Separation was performed on a Halo® C18 column using 0.05% formic acid and 5 μmol/L sodium formate in water, and 0.05% formic acid and 5 μmol/L sodium formate in acetonitrile as the mobile phase. The selectivity, precision, accuracy, extraction recovery, matrix effect and stability of the method were fully validated. Compared with the crude group, the parameters Cmax and AUC0–t of terrestroside B and terrestrosin K increased significantly (P < 0.05), but the Cmax and AUC0–t of polianthoside D, terrestrinin D, tribuluside A and terrestrosin D were decreased, terrestrosin D being especially decreased (P < 0.05), after oral administration of SFT extract. These results showed that the developed method was suitable for pharmacokinetic analysis of the six steroid saponins of CFT and SFT in rat plasma, and can be used to facilitate future clinical studies.
Embryonic ethanol exposure on zebrafish early development
Authors: Pinheiro‐da‐Silva Jaquelinne , Luchiari Ana Carolina 
Published: May 2021

AbstractIntroductionEmbryonic exposure to ethanol leads to a condition of physical, behavioral, and cognitive deficiencies named fetal alcohol spectrum disorders (FASD). The most severe variations are in fetal alcohol syndrome (FAS), which is easier to diagnose and not studied in animal models. On the other side, the pFAS (partial fetal alcohol syndrome) includes cases of alcohol‐related congenital disabilities and neurodevelopmental disorder with an inconclusive diagnosis. In recent years, the zebrafish has become a valuable model to study FASD and its variations.MethodsThis study characterizes the zebrafish embryonic and larval development after low and moderate ethanol concentration exposure. Fish eggs were exposed to 0.0%, 0.25%, 0.5%, and 1.0% ethanol at 24 hr postfertilization, and embryonic development was observed every 8 hr up to 120 hpf. It evaluated movements, phenotypic abnormalities, hatching, cardiac function and heartbeat frequency, larvae length at 120 hpf, and the apoptotic cells' fluorescence stained with acridine orange.ResultsEmbryonic exposure to 0.5% and 1% ethanol presented reduced body size, decreased heartbeat rate, higher numbers of apoptotic cells, and hatching time differences.ConclusionsOur results suggest any ethanol exposure during embryogenesis can be harmful and reinforces zebrafish as a suitable model for fetal alcohol spectrum disorders (FASD).
Data mining of an acoustic biomarker in tongue cancers and its clinical validation
Authors: Xiao Yudong , Wang Tao , Deng Wei , Yang Le , Zeng Bin , Lao Xiaomei , Zhang Sien , Liu Xiangqi , Ouyang Daiqiao , Liao Guiqing , Liang Yujie 
Published: May 2021

AbstractThe promise of speech disorders as biomarkers in clinical examination has been identified in a broad spectrum of neurodegenerative diseases. However, to the best of our knowledge, a validated acoustic marker with established discriminative and evaluative properties has not yet been developed for oral tongue cancers. Here we cross‐sectionally collected a screening dataset that included acoustic parameters extracted from 3 sustained vowels /ɑ/, /i/, /u/ and binary perceptual outcomes from 12 consonant‐vowel syllables. We used a support vector machine with linear kernel function within this dataset to identify the formant centralization ratio (FCR) as a dominant predictor of different perceptual outcomes across gender and syllable. The Acoustic analysis, Perceptual evaluation and Quality of Life assessment (APeQoL) was used to validate the FCR in 33 patients with primary resectable oral tongue cancers. Measurements were taken before (pre‐op) and four to six weeks after (post‐op) surgery. The speech handicap index (SHI), a speech‐specific questionnaire, was also administrated at these time points. Pre‐op correlation analysis within the APeQoL revealed overall consistency and a strong correlation between FCR and SHI scores. FCRs also increased significantly with increasing T classification pre‐operatively, especially for women. Longitudinally, the main effects of T classification, the extent of resection, and their interaction effects with time (pre‐op vs. post‐op) on FCRs were all significant. For pre‐operative FCR, after merging the two datasets, a cut‐off value of 0.970 produced an AUC of 0.861 (95% confidence interval: 0.785–0.938) for T3‐4 patients. In sum, this study determined that FCR is an acoustic marker with the potential to detect disease and related speech function in oral tongue cancers. These are preliminary findings that need to be replicated in longitudinal studies and/or larger cohorts.
First‐line therapy of bevacizumab plus chemotherapy versus cetuximab plus chemotherapy for metastatic colorectal cancer patients with mucinous adenocarcinoma or mucinous component
Authors: Zhou Yu‐Wen , Long Yi‐Xiu , Chen Ye , Liu Ji‐Yan , Pu Dan , Huang Jia‐Yan , Bi Feng , Li Qiu , Gou Hong‐Feng , Qiu Meng 
Published: May 2021

AbstractBackgroundTo compare the efficacy of first‐line bevacizumab plus chemotherapy with cetuximab plus chemotherapy based on the stratification of metastatic colorectal cancer (mCRC) patients with mucinous adenocarcinoma (MA) or mucinous component (MC).MethodsA retrospective study involving all mCRC patients receiving first‐line bevacizumab‐based or cetuximab‐based chemotherapy at our hospital from September 2013 to January 2020 was conducted. Overall survival (OS), progression‐free survival (PFS), and objective response rate (ORR) were compared between the cetuximab‐chemotherapy group and the bevacizumab‐chemotherapy group on the basis of the conventional pathological classification of MA or MC.ResultsA total of 620 patients with mCRC were included in our study, consisting of 141 (22.7%) patients with MA/MC and 479 (77.3%) patients with non‐mucinous adenocarcinoma (NMA). In the MA/MC cohort, patients who were treated with bevacizumab‐based chemotherapy were associated with significantly better OS than those treated with cetuximab‐base chemotherapy (30.0 vs. 26.3 months, p = 0.002), irrespective of tumor sites. The efficacy of bevacizumab‐based chemotherapy was higher in nearly all subgroups as shown in the subgroup analysis. In the NMA cohort, median OS was better in the cetuximab plus chemotherapy group than that in the bevacizumab plus chemotherapy group (32.2 vs. 27.0 months, p = 0.005) for left‐side mCRC patients, whereas OS was significantly longer in the bevacizumab plus chemotherapy group for right‐side mCRC patients (26.0 vs. 20.9 months, p = 0.013).ConclusionConventional pathological classification (e.g. MA/MC) should be considered when tailoring the individualized optimal treatment for mCRC. Bevacizumab plus chemotherapy as first‐line therapy may be the optimal option for patients with MA/MC.
A rare cause of lumbar nerve root compression: Extramedullary hematopoiesis in a patient with thalassemia major
Authors: Boussaa Hiba , Kaffel Dhia , Maatallah Kaouther , Lassoued Ferjani Hanene , Hamdi Wafa 
Published: May 2021

AbstractExtramedullary hematopoiesis (EMH) can rarely involve the epidural space, leading to spinal cord compression syndrome. No treatment guidelines have been established yet.
Two‐Dimensional Guanidine‐Based Hybrid Perovskites with Strong Dichroism for Multiwavelength Polarization‐Sensitive Detection
Authors: Lu Lei , Ma Yu , Wang Jiaqi , Liu Yi , Han Shiguo , Liu Xitao , Guo Wuqian , Xu Haojie , Luo Junhua , Sun Zhihua 
Published: April 2021

AbstractTwo‐dimensional (2D) organic–inorganic hybrid perovskites, benefiting from their natural anisotropy of quantum‐well motifs and optical properties, have shown remarkable polarization‐dependent responses superior to the 3D counterparts. Here, for the first time, multiwavelength polarization‐sensitive detectors were fabricated by using single crystals of a guanidine‐based 2D hybrid perovskite, (BA)2(GA)Pb2I7 (where BA+ is n‐butylammonium and GA+ is guanidium). Its unique 2D quantum‐well structure results in strong crystallographic‐dependence of optical absorption. Strikingly, our crystal‐based photodetector exhibits a prominent photocurrent dichroic ratio (Imax/Imin) of ∼2.2 at 520 nm, higher than the typical 2D inorganic materials (GeSe, ∼1.09, PdSe2, ∼1.8). In addition, notable dichroic ratios of 1.29 and 1.23 at 405 nm and 637 nm are also created for the multiwavelength polarized‐light detection. The prominent detecting performances, including low dark current (1.6×10−11 A), considerable on/off ratio (∼2×103), high photodetectivity (∼3.3×1011 Jones) and responsivity (∼12.01 mA W−1), make (BA)2(GA)Pb2I7 a promising candidate for polarized‐light detection. This work sheds light on the rational engineering of new 2D hybrid perovskites for the high‐performance optoelectronic device applications.
CeO2/TiO2/SiO2 nanocatalyst for the photocatalytic and sonophotocatalytic degradation of chlorpyrifos
Authors: Mansourian Reza , Mousavi Seyedeh Maryam , Alizadeh Shahin , Sabbaghi Samad 
Published: May 2021

AbstractA new nanohybrid photocatalyst named cerium (IV) oxide (CeO2)/TiO2 (titania)/silicon dioxide (SiO2) was firstly synthesized employing the co‐precipitation technique to elaborate the degradation efficiency of chlorpyrifos (CPS) as a relatively indelible organophosphorus pesticide in deionized water in photocatalytic and sonophotocatalytic processes. The influence of various parameters, including photocatalyst dosage, the CPS pesticide concentration, pH, and irradiation time, was investigated, and the optimal parameters for photodegradation and sonophotodegradation were determined. The activity and the electrical energy of this photocatalyst in the photodegradation and sonophotodegradation processes were compared, and it was revealed that the sonophotocatalytic process was superior to the photocatalytic one (about 15%). Results depicted that it can be employed four times for the photocatalytic reactions with the same yield of CPS degradation. Besides, the CPS degradation efficiency at the optimum conditions was found to be 81.1% and 90.8% for the photo‐degradation and sonophotodegradation, respectively. Pursuant to the kinetic studies, the kinetics models that govern these processes are leaner with acceptable accuracy.
Conformational Space Sampled by Domain Reorientation of Linear Diubiquitin Reflected in Its Binding Mode for Target Proteins
Authors: Hou Xue‐Ni , Sekiyama Naotaka , Ohtani Yasuko , Yang Feng , Miyanoiri Yohei , Akagi Ken‐ichi , Su Xun‐Cheng , Tochio Hidehito 
Published: April 2021

AbstractLinear polyubiquitin chains regulate diverse signaling proteins, in which the chains adopt various conformations to recognize different target proteins. Thus, the structural plasticity of the chains plays an important role in controlling the binding events. Herein, paramagnetic NMR spectroscopy is employed to explore the conformational space sampled by linear diubiquitin, a minimal unit of linear polyubiquitin, in its free state. Rigorous analysis of the data suggests that, regarding the relative positions of the ubiquitin units, particular regions of conformational space are preferentially sampled by the molecule. By combining these results with further data collected for charge‐reversal derivatives of linear diubiquitin, structural insights into the factors underlying the binding events of linear diubiquitin are obtained.
A Machine Learning Approach for Metal Oxide Based Polymer Composites as Charge Selective Layers in Perovskite Solar Cells
Authors: Yildirim Murat Onur , Gok Elif Ceren , Hemasiri Naveen Harindu , Eren Esin , Kazim Samrana , Oksuz Aysegul Uygun , Ahmad Shahzada 
Published: May 2021

AbstractA library of metal oxide‐conjugated polymer composites was prepared, encompassing WO3‐polyaniline (PANI), WO3‐poly(N‐methylaniline) (PMANI), WO3‐poly(2‐fluoroaniline) (PFANI), WO3‐polythiophene (PTh), WO3‐polyfuran (PFu) and WO3‐poly(3,4‐ethylenedioxythiophene) (PEDOT) which were used as hole selective layers for perovskite solar cells (PSCs) fabrication. We adopted machine learning approaches to predict and compare PSCs performances with the developed WO3and its composites. For the evaluation of PSCs performance, a decision tree model that returns 0.9656 R2score is ideal for the WO3‐PEDOT composite, while a random forest model was found to be suitable for WO3‐PMANI, WO3‐PFANI, and WO3‐PFu with R2scores of 0.9976, 0.9968, and 0.9772 respectively. In the case of WO3, WO3‐PANI, and WO3‐PTh, a K‐Nearest Neighbors model was found suitable with R2scores of 0.9975, 0.9916, and 0.9969 respectively. Machine learning can be a pioneering prediction model for the PSCs performance and its validation.
OH− Conductive Properties and Water Uptake of Anion Exchange Thin Films
Authors: Wang Fangfang , Wang Dongjin , Nagao Yuki 
Published: April 2021

AbstractSeveral investigations have indicated that proton conduction and hydration properties of acidic ionomers differ from those of membranes. However, relations between the OH− conductivity and water uptake in thin film forms of anion exchange membranes have not been reported yet. For this study, new in situ measurements were established to elucidate the OH− conductivity and water uptake without allowing any influence of CO2 from the air. Poly[(9,9‐bis(6′‐(N,N,N‐trimethylammonium)‐hexyl)‐9H‐fluorene)‐alt‐(1,4‐benzene)], denoted as PFB+, was synthesized as a model ionomer. The highest OH− conductivity of 273 nm‐thick PFB+ film was 5.3×10−2 S cm−1 at 25 °C under 95 % relative humidity (RH), which is comparable to the reported OH− conductivity of PFB+ membrane. Reduced OH− conductivity was found in the thinner film at 95 % RH. The decreased OH− conductivity is explainable by the reduced number of water molecules contained in the thinner film. The OH− conductivity was reduced only slightly under the same water uptake.
A 4GS/s 8‐bit time‐interleaved SAR ADC with an energy‐efficient architecture in 130 nm CMOS
Authors: Solis Fredy , Fernández Bocco Álvaro , Galetto Agustín C. , Passetti Leandro , Hueda Mario R. , Reyes Benjamín T. 
Published: May 2021

AbstractThis paper presents the design, implementation, and measurements of a 4 GS/s, 8‐bit resolution, time‐interleaved (TI) analog‐to‐digital converter (ADC) comprised of 32 asynchronous successive approximation register (SAR) ADCs. The chip is fabricated in a 130 nm CMOS process. This prototype achieves the highest sampling rate and the best efficiency for a SAR TI‐ADC in the process used. An energy‐efficient hierarchical T&H architecture, ranked in a 4 × 8 structure, has been used to interleave the aforementioned high number of SAR ADCs avoiding the power hungry buffers typically used in the input signal path and/or T&H outputs. The sampling architecture includes programmable delay cells with up to 104 fs resolution to calibrate sampling time errors. Additionally, the input matching network uses an on‐chip inductance to mitigate the impact of the packaging on the analog bandwidth. An efficient SAR ADC implementation is achieved by an optimized comparator design, which allows for both, noise and asynchronous clock control, and includes background DC offset calibration. The test chip is the core of a measurement platform dedicated to the evaluation of mismatch calibration techniques for ADCs used in high speed digital communication systems. To enable this application, a 32Gb/s low‐voltage differential signaling interface is included to transmit the samples off‐chip without any decimation. The TI‐ADC achieves a peak 7.09 effective number of bits (ENOB) (5.47ENOB at Nyquist) and 1.3 GHz input bandwidth with a power consumption of 93 mW at 1.2 V. Each SAR ADC channel achieves a Walden figure of merit (FOM) of 123fJ/conv‐step and owing to the efficient interleaved architecture the full TI‐ADC achieves a peak FOM of 171fJ/conv‐step (526fJ/conv‐step at Nyquist).
Channel estimation and secure data transmission using hybrid particle swarm optimisation–gray wolf optimisation‐leaky least‐Mean‐Square and affine elliptic curves cryptography algorithm in MU‐multi‐input multi‐output orthogonal frequency division multiplexing system
Authors: R Jeya , Amutha B. 
Published: May 2021

SummaryIn a huge multi‐input multi‐output orthogonal frequency divisions multiplexing (MIMO‐OFDM), an exact Channel State Information (CSI) is required to understand the system performance, which includes high spectrum together with energy efficiency. Using the OFDM, substantial numbers of pilots are distributed over a huge range of time–frequency sources to efficiently assess a vast range of channel coefficients in space along with the frequency domains, forfeiting spectral efficiency. Here, an optimised Channel Estimation (CE) framework aimed at the MU‐MIMO OFDM system is proposed utilising Hybrid Particle Swarm Optimisation–Gray Wolf Optimisation‐Leaky Least‐Mean‐Square (HPG‐LLMS) to attain high accurateness and secure data transmission (DT) with the aid of proposed Affine ECC. Herein, the video is considered as an input in the transmitter side and transformed into data frames and compressed with the help of ASCII‐based Huffman algorithm. Using Affine ECC, the compressed data are encrypted as well as modulated with the help of the MQPSK method. Then, transmute the modulated data into IFFT and incorporate the Guard Interval (GI) to the data. And then, over the Multi‐Path Channel (MPC), the symbols will be passed on to the receiver with the Additives White Gaussian Noise (AWGN). Execute the Inverse operations on the receiver side and centred on fuzzy centred priority scheduling algorithm (FPSA), sent the data to the user. Lastly, utilising HPG‐LLMS, the CE is performed.