bluuebunny/crossref_metadata_2025_split huggingface dataset:
Povidone‐Phosphotungstic Acid Hybrid: An Efficient and Environmentally Benign Catalyst for the Synthesis of Quinazolinone Derivatives
Authors: Kagne Raju , Kalalawe Virbhadra , Niwadange Sandeep , Mahurkar Shreyash , Munde Dashrath 
Published: August 2020

AbstractIn this research, a novel strategy for synthesis of quinazolinones has been formulated via one pot condensation of aromatic aldehydes, isatoic anhydride, and aniline by employing prepared povidone‐phosphotungstic acid (PVP‐PWA) hybrid as a novel solid acid heterogenous catalyst in methanol at 80 °C. The synthesized PVP‐PWA is confirmed by FTIR, XRD and studied for TGA, BET plots. The reaction is optimized for different solvents and loading of catalyst. The yields of all quinazolinone derivatives are observed in the range of 78–86%. All the synthesized quinazolinones are investigated by spectral data. The use of ecologically benign catalyst, good atom economy, environmental affordability, and easy work up makes this protocol sustainable.
Study of Bimolecular Quenching Reactions of Coumarin Dye C1 by the Fluorescence Behavior in Toluene and Butanol Binary Mixtures
Authors: Sharma Kalpana , Melavanki Raveendra , Muttannavar V. T. , Bhavya P. , U. Meghana , B. Suma 
Published: August 2020

AbstractInferable from the significance of solvent mixtures in practical chemistry, toluene (TL) and butanol (BL) mixtures are used to study fluorescence behavior of coumarin dye C1 namely 3‐hydroxy‐3‐[2‐oxo‐2‐(2‐oxo‐2H‐chromen‐3‐yl)‐ethyl]‐1,3‐dihydro‐indol‐2‐one. Bimolecular quenching reaction studies of C1 with aniline as quencher are made in mixtures of TL–BL to know the effect of viscosity and dielectric constant variation at room temperature. The quenching process is studied in all solvent mixtures by steady state method. Quenching is characterized by Stern–Volmer (S–V) plots having upward curvature. Analysis of modified S–V equations which accounts both static and dynamic quenching allows calculating bimolecular quenching rate constant. The bimolecular quenching reactions are found to be significantly larger. Further finite sink approximation model is invoked so as to check whether reactions are diffusion limited. The extents of these rate parameters demonstrate that positive deviations in the S–V plot are because of the presence of apparent static and dynamic quenching process.
Theoretical Study of Surface Plasmon Resonance in P3HT:PCBM/Cu Nano Film
Authors: Das Malyaj , Kushwaha Kamal Kumar , Sharma Divakar 
Published: August 2020

AbstractThe present paper discusses thoretical study about the surface plasmon resonance (SPR) properties of poly‐3 hexylthiophene‐2,5‐diyl, 6,6‐phenylC61 butyric acid methyl ester: Cu nano film with the variation of thickness of Cu nano film. The present theoretical studies show that the variation of thickness of the Cu nano film gives better result as compared to gold and silver nano films. The SPR Q‐factor infers that copper would be a good candidate to replace gold as potential plasmonic materials.
Physical and Fourier Transform Infrared Studies of ZnO‐Al2O3‐Li2O‐B2O3 Glass System Incorporated with Cu2+ and Mn3+ Ions
Authors: Rao B. Tirumala , Cole Sandhya 
Published: August 2020

AbstractZinc Alumino Lithium borate (ZnAlLiB) glasses of different compositions doped with Cu2+ and Mn3+ ions have been prepared using a conventional melt quenching technique. Fourier transform infrared (FT‐IR) studies have been carried out for ZnAlLiB glasses. The physical properties have been measured. The FT‐IR studies indicate that insertion of Cu2+ ions produces [BO3] and [BO4] basic structural units by breaking the boroxol (B3O6) ring, while manganese ions are found to gradually depolymerize MnO2─B2O3 glass matrix. This report presents the synthesis and FT‐IR studies of zinc alumino lithium borate glasses doped with CuO and MnO2. The local structure of copper and manganese ions in the glass system can be studied.
Upregulation of secreted phosphoprotein 1 affects malignant progression, prognosis, and resistance to cetuximab via the KRAS/MEK pathway in head and neck cancer
Authors: Liu Kai , Hu Huiying , Jiang Huanyu , Liu Chenglei , Zhang Haidong , Gong Shanchun , Wei Dongmin , Yu Zhenkun 
Published: August 2020

AbstractAcquired resistance is a barrier to cetuximab efficacy in patients with head and neck squamous cell carcinoma (HNSCC). Secreted phosphoprotein 1 (SPP1) is involved in various biological processes, including immune responses, cancer progression, and prognosis in many cancers, while little is known in HNSCC. Bioinformatics methods were used to identify candidate genes and further in vivo and in vitro experiments were performed to examine and validate the function of SPP1. We found that SPP1 was upregulated and has been found to have an oncogenic role in HNSCC. We further confirmed that overexpression of SPP1 affected proliferation, migration, invasion, and survival, and inhibited apoptosis, whereas silencing of SPP1 yielded opposite results to those of SPP1 overexpression. In addition, activation of the KRAS/MEK pathway contributed to the SPP1‐induced malignant progression of HNSCC and resistance to cetuximab. Furthermore, SPP1 knockdown or an MEK inhibitor overcame this cetuximab‐resistance pattern. Taken together, our findings for the first time identify the role of SPP1 in tumor promotion, prognostic prediction, and potential therapeutic targeting, as well as resistance to cetuximab in HNSCC.
LncRNA UCA1 maintains the low‐tumorigenic and nonmetastatic status by stabilizing E‐cadherin in primary prostate cancer cells
Authors: Zhao Xian , Wang Yanli , He Jianfeng , Deng Rong , Huang Xiaojun , Guo Yanmin , Li Lian , Xie Ruiyu , Yu Jianxiu 
Published: August 2020

AbstractLong noncoding RNAs (LncRNAs) have emerged as important players in cancer biology. Increasing evidence suggests that LncRNAs are frequently dysregulated in cancer and may function as oncogenes or tumor suppressors. Urothelial carcinoma associated 1 (UCA1), a LncRNA, firstly identified in bladder transitional cell carcinoma, seems to act as an oncogene in many different types of human cancers by promoting cell proliferation and migration. In this study, we revealed a novel biological function of UCA1, which was different from that reported by previous studies, was responsible for maintaining the low‐tumorigenic, nonmetastatic phenotypes in primary prostate epithelial cells. UCA1 could stabilize E‐cadherin protein by preventing the interaction between E‐cadherin and its E3 ligase MDM2, which suppressed MDM2‐mediated ubiquitination and degradation of E‐cadherin. In addition, we also found that UCA1 acted as a sponge of miR‐296‐3p, which targeted E‐cadherin gene CDH1 messenger RNA at the posttranscription level. Taken together, these findings demonstrated that UCA1 had a new important role in effectively keeping E‐cadherin at a high level through a dual mechanism, which maintained primary prostate cancer cells at the low‐tumorigenic and nonmetastatic status.
MYC‐binding lncRNA EPIC1 promotes AKT‐mTORC1 signaling and rapamycin resistance in breast and ovarian cancer
Authors: Wang Yifei , Zhang Min , Wang Zehua , Guo Weiwei , Yang Da 
Published: August 2020

AbstractAKT‐mTORC1 (mammalian target of rapamycin complex 1) signaling pathway plays a critical role in tumorigenesis and can be targeted by rapamycin. However, the underlying mechanism of how long noncoding RNA (lncRNAs) regulate the AKT‐mTORC1 pathway remains unclear. EPIC1 (epigenetically‐induced lncRNA 1) is a Myc‐binding lncRNA, which has been previously demonstrated to be overexpressed in multiple cancer types. In a pathway analysis including 4962 cancer patients, we observed that lncRNA EPIC1 expression was positively correlated with the AKT‐mTORC1 signaling pathway in more than 10 cancer types, including breast and ovarian cancers. RNA‐seq analysis of breast and ovarian cancer cells demonstrated that EPIC1‐knockdown led to the downregulation of genes in the AKT‐mTORC1 signaling pathway. In MCF‐7, OVCAR4, and A2780cis cell lines, EPIC1 knockdown and overexpression, respectively, inhibited and activated phosphorylated AKT and the downstream phosphorylation levels of 4EBP1 and S6K. Further knockdown of Myc abolished the EPIC1′s regulation of AKT‐mTORC1 signaling; suggested that the regulation of phosphorylation level of AKT, 4EBP1, and S6K by EPIC1 depended on the expression of Myc. Moreover, EPIC1 overexpressed MCF‐7, A2780cis, and OVCAR4 cells treated with rapamycin showed a significant decreasing in rapamycin mediated inhibition of p‐S6K and p‐S6 comparing with the control group. In addition, Colony Formation assay and MTT assay indicated that EPIC1 overexpression led to rapamycin resistance in breast and ovarian cancer cell lines. Our results demonstrated the lncRNA EPIC1 expression activated the AKT‐mTORC1 signaling pathway through Myc and led to rapamycin resistance in breast and ovarian cancer.
Uncooled antenna‐coupled terahertz thermal detector using CMOS process
Authors: Wang Xu 
Published: August 2020

AbstractThis article presents an uncooled monolithic resonant terahertz (THz) thermal detector using a standard 55 nm CMOS process without any postprocessing procedures. The detector is composed of a resonant loop antenna loaded with a polysilicon resistor and a proportional to absolute temperature (PTAT) sensor which is used as a temperature sensitive device. The basic operation principle, overall design considerations and relatively better measurement results are demonstrated. A maximum responsivity of 30.6 V/W and a minimum noise equivalent power (NEP) of 1.68 μW Hz for the thermal detector are measured at the operating frequency of 910 GHz.
High‐sensitive temperature sensor based on ethanol‐filled elliptical‐core side‐hole fiber Sagnac interferometer
Authors: Gong Zhonghua , Zhang Hao , Liu Teng , Huang Bangcai , Liu Bo , Sun Jianjun , Wang Dongbo 
Published: August 2020

AbstractThe birefringence properties of two types of side‐hole fibers have been numerically studied, based on which a Sagnac fiber interferometer employing ethanol‐filled side‐hole fibers is proposed and experimentally demonstrated for high‐sensitive temperature measurement. Thanks to highly temperature‐sensitive refractive index of ethanol infiltrated in the air holes of side‐hole fibers, high‐sensitive temperature measurement could be realized by monitoring fiber‐birefringence‐induced resonance wavelength shift of the fiber Sagnac interferometer in response to environmental temperature variation. Experimental results show that within a temperature range of 26°C to 54°C, there exists some critical temperature point around 40°C, on both sides of which the resonance dips exhibit inverse temperature‐dependent shift behaviors. A temperature sensitivity of 1.10 nm/°C is experimentally achieved for our proposed side‐hole fiber Sagnac interferometer.
Dynamic B0 shimming for multiband imaging using high order spherical harmonic shims
Authors: Hetherington Hoby P. , Moon Chan Hong , Schwerter Michael , Shah Nadim Joni , Pan Jullie W. 
Published: August 2020

PurposeTo describe and implement a strategy for dynamic slice‐by‐slice and multiband B0 shimming using spherical harmonic shims in the human brain at 7T.TheoryFor thin axial slices, spherical harmonic shims can be divided into pairs of shims (z‐degenerate and non‐z‐degenerate) that are spatially degenerate, such that only ½ of the shims (non‐z‐degenerate) are required for single slice optimizations. However, when combined, the pairs of shims can be used to simultaneously generate the same in‐plane symmetries but with different amplitudes as a function of their z location. This enables multiband shimming equivalent to that achievable by single slice‐by‐slice optimization.MethodsAll data were acquired at 7T using a spherical harmonic shim insert enabling shimming up through 4th order with two additional 5th order shims (1st‐4th+). Dynamic shim updating was achieved using a 10A shim power supply with 2 ms ramps and constrained optimizations to minimize eddy currents.ResultsIn groups of eight subjects, we demonstrated that: 1) dynamic updating using 1st‐4th+ order shims reduced the SD of the B0 field over the whole brain from 32.4 ± 2.6 and 24.9 ± 2 Hz with 1st‐2nd and 1st‐4th+ static global shimming to 15.1 ± 1.7 Hz; 2) near equivalent performance was achieved when dynamically updating only the non‐z‐degenerate shims (14.3 ± 1.5 Hz), or when a using multiband shim factor of 2, MBs = 2, and all shims (14.4 ± 2.0 Hz).ConclusionHigh order spherical harmonics provide substantial improvements over static global shimming and enable dynamic multiband shimming with near equivalent performance to that of dynamic slice‐by‐slice shimming. This reduces distortion in echo planar imaging.
Global and peak local specific absorption rate control on parallel transmit systems using k‐means SAR compression model
Authors: Mao Xianglun , Bari Sumra , Love David J. , Rispoli Joseph V. 
Published: August 2020

PurposeTo improve the specific absorption rate (SAR) compression model capability in parallel transmission (pTx) MRI systems.MethodsA k‐means clustering method is proposed to group voxels with similar SAR behaviors in the scanned object, providing a controlled upper‐bounded estimation of peak local SARs. This k‐means compression model and the conventional virtual observation point (VOP) model were tested in a pTx MRI framework. The pTx pulse design with different SAR controlling schemes was simulated using a numerical human head model and an eight‐channel 7T coil array. Multiple criteria (including RF power, global and peak local SARs, and excitation accuracy) were compared for the performance testing.ResultsThe k‐means compression model generated a narrower overestimation bound, leading to a more accurate local SAR estimation. Among different pTx pulse design approaches, the k‐means compression model showed the best trade‐off between the SAR and excitation accuracy.ConclusionsThe developed SAR compression model is advantageous for pTx framework given the narrower overestimation bound and control over the compression ratio. Results also illustrate that a moderate increase of maximum RF power can be useful for reducing the maximum local SAR deposition.
Measurements of venous oxygen saturation in the superior sagittal sinus using conventional 3D multiple gradient‐echo MRI: Effects of flow velocity and acceleration
Authors: Cheng Chou‐Ming , Chou Chih‐Che , Yeh Tzu‐Chen , Chung Hsiao‐Wen 
Published: August 2020

PurposeThis work investigates the effects of flow acceleration in the superior sagittal sinus on slice‐dependent variations in venous oxygen saturation (SvO2) estimations using susceptibility‐based MR oximetry.MethodsThree‐dimensional multiple gradient‐echo images, with first‐order flow compensation along the anterior–posterior readout direction for the first echo, were acquired twice from 15 healthy volunteers. For all slices, phases within the superior sagittal sinus were fitted using linear regression across four TEs to obtain the Pearson’s correlation coefficients (PCCs), the largest of which corresponded to minimum acceleration influence. SvO2 derived from odd echoes on this slice was used to assess interscan difference, and compared with the central 15th slice for slice‐dependent difference, both using Bland‐Altman analysis. Within‐scan interslice SvO2 consistency was examined versus PCC. Multislice‐averaged SvO2 values were then computed from slices with PCCs above a certain threshold.ResultsSlice‐dependent difference in SvO2 varied from −16.2% to 21.5% at two SDs, in agreement with a recent report, and about twice larger than interscan differences for the automatically selected slice (−7.5% to 10.3%) and for the central 15th slice (−8.0% to 8.8%). For slices with PCCs higher than −0.98, interslice SvO2 deviations were all found to be less than 5.0%. Multislice‐averaged SvO2 with PCCs higher than −0.98 further reduced interscan difference to −4.7% to 8.2%.ConclusionSlice‐dependent variations in SvO2 may partly be explained by the effects of flow acceleration. Our method may enable conventional 3D multiple gradient echo to be used for SvO2 estimations in the presence of pulsatile flow.
Impact of gestational diabetes on pelvic floor: A prospective cohort study with three‐dimensional ultrasound during two‐time points in pregnancy
Authors: Sartorão Filho Carlos I. , Pinheiro Fabiane A. , Prudencio Caroline B. , Nunes Sthefanie K. , Takano Luiz , Enriquez Eusebio M. A. , Orlandi Maiara I. G. , Junginger Baerbel , Hallur Raghavendra L. S. , Rudge Marilza V. C. , Barbosa Angélica M. P. 
Published: August 2020

AbstractAimTo evaluate the pelvic floor (PF) biometry using three‐dimensional ultrasound (US) at two‐time points of gestational in pregnant women with gestational diabetes mellitus (GDM).MethodsA prospective cohort study conducted at the Perinatal Diabetes Research Center including 44 pregnant women with GDM and 66 pregnant women without GDM at 24 to 28 weeks of gestation. Three‐dimensional transperineal US was performed at 24 to 28 and 34 to 38 weeks of gestation in the lithotomy position at rest. The axial plane of the minimal Levator hiatal dimensions was used to determine Levator ani muscle and Hiatal area (HA) biometry at 24 to 28 and 34 to 38 weeks of gestation.ResultsOf the 110 pregnant women, 100 (90.9%) completed the follow‐up at 34 to 38 weeks of gestation. The evaluation by US showed a negative biometric change between the two‐time points, during pregnancy in women with GDM; in the HA (β coefficient: estimative of effect in biometric progression according to GDM diagnosis, using the non‐GDM group as reference = −6.76; P = .020), anteroposterior diameter (β = −5.07; P = .019), and Levator ani thickness (β = −12.34; P = .005).ConclusionsPregnant women with GDM had a significantly lower than expected percentage of changes in biometry of Levator ani thickness and HA from 24 to 28 to 34 to 38 weeks of gestation when compared with the group of pregnant women without GDM. GDM alters the morphology of PF structures assessed by three‐dimension US. This reported complication may be implicated in adverse birth outcomes and may play a role in the development of PF dysfunction.
An unconventional method for calculating porosity of marine clay deposits using the 2D resistivity method
Authors: Rosli Najmiah , Saad Rosli , Rahman Nazrin , Ismail Nur Azwin 
Published: August 2020

ABSTRACTVarious methods were earlier designed to calculate porosity of a formation, but many of them are reliant on physical soil sampling and/or laboratory measurements. The present work examines a recently proposed method, which we call here as Sample‐free Porosity Calculation from Resistivity Imaging Data (SPyCRID), to calculate porosity of unconsolidated soils. By conjoining Archie's and Waxman–Smits’ equations, SPyCRID can achieve high accuracy in porosity calculation, while requiring no physical soil‐sampling data. Two‐dimensional resistivity data acquired at Segantang Garam were modelled to calibrate SPyCRID's workflow and to devise data constraints for marine clay and brackish pore‐fluid conditions. Measured porosities from soil samples were used only for calibration and validation purposes. With data transformation added into the workflow, the performance of SPyCRID was improved as it was possible to achieve more precise value for the calculated porosity (error ≤3.1%). The final step to establish SPyCRID's competency was implemented through testing SPyCRID at the Nibong Tebal test site that has similar geological conditions to the model. Results from this test site showed nominal errors (≤3.9%) in the calculated porosity. SPyCRID could successfully calculate the porosity of the unconsolidated, marine clayey soils with a confidence limit exceeding 96%, while requiring no physical sampling data.
Evaluation method and key factor analysis for thermal protection performance of multifunctional integrated ablative materials
Authors: Li Weijie , Huang Jie , Zhang Zhongwei , Huang Haiming , Liang Jun , Wang Liyan 
Published: August 2020

AbstractThe thermal protection materials of hypersonic aircrafts in near space are subjected to extremely serious aerothermodynamic environment under long heating time, higher enthalpy, larger heat accumulation, and so forth. Proposing new concepts of materials and accurate evaluation of their performance take the dominant roles in developing high‐efficiency thermal protection materials under this severe environment. By introducing the concepts of gradient and fiber hybridization, this study proposes a multifunctional integrated ablative material scheme to replace heritage ones in order to improve the heat insulation, ablation resistant, and weight reduction capacities. Meanwhile, a thermal‐fluid‐ablative coupling mathematical model taking the manufacturing processing parameters reflecting the gradient and fiber hybridization into consideration is established. Furthermore, the sensitivity analysis for the manufacturing processing parameters is carried out. A simulation tool is developed based on writing FORTRAN codes to solve the multi‐field coupling model numerically. The results that the model and code are effective in analyzing the material's performance and the key manufacturing processing parameters influencing on the thermal protection performance of multifunctional integrated ablative material are pointed out. This work helps to design new thermal protection materials for hypersonic vehicles under extreme aerothermodynamic environments.Highlights
New scheme of multifunctional integrated ablative material is proposed.
Developed multi‐field coupling thermal protection model for new material is established.
A bridge between material responses and manufacture processing parameters is built.
Key factors influencing on material performance are pointed out by sensitivity analysis.