bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acid catalyzed cross‐linking of polyvinyl alcohol for humidifier membranes
Authors: Michele Andre , Paschkowski Patrick , Hänel Christopher , Tovar Günter E. M. , Schiestel Thomas , Southan Alexander 
Published: September 2021

AbstractPolyvinyl alcohol (PVA) is a hydrophilic polymer well known for good film forming properties, high water vapor permeance JW, and low nitrogen permeance. However, depending on molar mass and temperature, PVA swells strongly in water until complete dissolution. This behavior affects the usability of PVA in aqueous environments and makes cross‐linking necessary if higher structural integrity is envisaged. In this work, PVA networks are formed by thermal cross‐linking in the presence of p‐toluenesulfonic acid (TSA) and investigated in a design of experiments approach. Experimental parameters are the cross‐linking period tc, temperature ϑ and the TSA mass fraction wTSA. Cross‐linking is found to proceed via ether bond formation at all reaction conditions. Degradation is promoted especially by a combination of high wTSA, tc and ϑ. Thermal stability of the networks after preparation is strongly improved by neutralizing residual TSA. Humidification membranes with a JW of 6423 ± 63.0 gas permeation units (GPU) are fabricated by coating PVA on polyvinyliden fluoride hollow fibers and cross‐linking with TSA. Summarizing, the present study contributes to a clearer insight into the cross‐linking of PVA in presence of TSA, the thermal stability of the resulting networks and the applicability as selective membrane layers for water vapor transfer.
Physicochemical characterization and flocculation performance evaluation ofPAC/PMAPTACcomposite flocculant
Authors: Guo Yiming , Li Xiaoxiao , Sun Jun , Liu Yanyan , Wang Hua , Ding Jianjun , Chen Lin , Tian Xingyou , Yuan Yun 
Published: September 2021

AbstractA novel inorganic–organic composite flocculant was prepared with polyaluminum chloride (PAC) and poly(methacrylamido propyl trimethyl ammonium chloride) (PMAPTAC). To understand the physicochemical characterization of PAC/PMAPTAC and evaluate its flocculation efficiency, the interactions of PAC and cationic polymer were investigated, then the characterization and flocculation performance of PAC/PMAPTAC and PAC/Poly‐dimethyldiallylammonium chloride (PDMDAAC) were compared. The results showed that there were obvious interactions between PAC and cationic polymer in composite flocculant. The cationic polymer chain exhibited a coiled state in PAC solution, and the curly degree of PMAPTAC chain was lower than that of PDMDAAC due to the intermolecular association of methyl of PMAPTAC. The cationic polymer enhanced the charge neutralization ability of PAC and changed the aluminum hydrolysis polymerization species of PAC from low and medium polymeric species to high‐polymeric species. The flocculation sedimentation experiments turned out that the charge neutralization and bridging ability of PAC/PMAPTAC was higher than that of PAC/PDMDAAC, and the increase of molecular weight or content of PMAPTAC in PAC/PMAPTAC could enhance the charge neutralization and adsorption bridging ability simultaneously. The enhanced effects may come from the exist of polymer and the interactions between PAC and cationic polymer in composite flocculant.
Near‐infrared light responsive dendrimers facilitate the extraction of bicalutamide from human plasma and urine
Authors: Mahdavijalal Mohammadreza , Ahmad Panahi Homayon , Niazi Ali , Tamaddon Atefeh 
Published: September 2021

AbstractBackgroundToday, it is well accepted that the quantitative measurement of anti‐cancer drugs in human biological samples requires the development and validation of efficient bioanalytical methods. This study attempts to provide a high‐capacity and thermo‐sensitive nano‐adsorbent for bicalutamide extraction from human biological fluids.Main Methods and Major ResultsIn this study, five generations of thermo‐sensitive dendrimers were synthesized onto the surface of WS2 nano‐sheets. After drug‐loading process from body fluids, the near‐infrared (NIR) light (at 808 nm) was applied and light‐to‐heat conversion by the WS2 nano‐sheets led to shrinkage in polymer chains, resulting the release of the entrapped drug. Finally, the extracted drug was analyzed via HPLC‐UV system (at 270 nm). The final nano‐adsorbent was described via FE‐SEM, XRD, FT‐IR, and TGA techniques. The adsorption isotherm data were well fitted by Langmuier isotherm model (R2 = 0.9978). The mean recoveries for spiking bicalutamide at three different concentrations in plasma and urine samples were 92.12% and 94.54% under the NIR light irradiation.Conclusions and ImplicationsWe have developed a smart strategy to analyze bicalutamide in biological samples using near‐infrared light irradiation in a controlled manner. All the results indicate the promising application of the proposed method for the extraction and determination of bicalutamide.
Synthesis and biological evaluation of dimeric peptide derivatives as proliferation‐stimulating agents in human follicle dermal papilla cells
Authors: Jeong Jisu , Park Kyeong‐Yong , Kim Jiyeon 
Published: September 2021

AbstractTripeptides containing lysine such as Arg‐His‐Lys (AHK) and Gly‐His‐Lys (GHK) are known to modulate biological regeneration. Here, we synthesized and evaluated the biological effects of dimeric peptide derivatives on the proliferation of human follicle dermal papilla cells (HFDPCs) in an in vitro model. Treatment of dimeric peptide derivatives stimulated the proliferation of HFDPCs more when compared to the group treated with AHK. Dimeric peptide derivatives also stimulated the phosphorylation of mitogen‐activated protein kinases extracellular signal‐regulated kinase (ERK1/2). In particular, peptide No. 20 Arg‐Trp‐Lys (AWK') was found to promote the phosphorylation of ERK1/2 most strongly. In addition, peptide No. 20 (AWK') activated mRNA expression of hair regeneration‐related genes such as VEGF, FGF‐2, and FGF‐7. Our results suggest that dimeric peptide derivatives exert a stimulating effect on HFDPC proliferation through activation of ERK1/2 signaling and without significant cytotoxicity. These results provide important data for the development of peptide‐based hair‐regenerative agents and treatment of alopecia.
LC–MS/MS for determination of aesculetin in rat plasma and its application to a pharmacokinetic study
Authors: Jiao Weijie , Qin Nan , Wang Kun , Wu Dongmei , Yu Hongyan , Du Lei , Wu Guiyue , Wu Hong , Zhao Xu 
Published: September 2021

AbstractAesculetin, a coumarin compound present in the sancho tree and chicory, exhibits excellent antioxidant and anti‐inflammatory activities in the vascular and immune system. In this study, a rapid and sensitive ultra‐high performance liquid chromatography electrospray ionization–tandem mass spectrometry (UHPLC–ESI–MS/MS) method was established and validated for the determination of aesculetin in rat plasma. Plasma samples were prepared by protein precipitation with acetonitrile. Chromatographic separation was performed on an Acquity UPLC HSS T3 C18 column (2.1 × 100 mm, 1.8 μm) with gradient elution at a flow rate of 0.3 ml/min, using mobile phase consisting of 0.1% formic acid (A) and acetonitrile (B). Aesculetin and puerarin (internal standard) were detected by multiple reaction monitoring in negative ion mode. The method was fully validated according to the US Food and Drug Administration guidelines. The calibration curve was linear over the range of 2–1,000 ng/ml with correlation coefficient >0.9980. The carry‐over, matrix effect, extraction recovery, dilution effect, intra‐ and inter‐day precision and the accuracy were within acceptable limits. The method was then applied to a pharmacokinetic study of aesculetin in rats. After oral administration at doses of 5, 10 and 20 mg/kg, the plasma concentration reached peaks of 95.7, 219.9, 388.6 ng/ml at times of 1.22–1.78 h. The oral bioavailability was calculated as 15.6–20.3% in rat plasma. The result provided pre‐clinical information for further application of aesculetin.
Metacognitive therapy versus cognitive–behavioral therapy in adults with generalized anxiety disorder: A 9‐year follow‐up study
Authors: Solem Stian , Wells Adrian , Kennair Leif Edward Ottesen , Hagen Roger , Nordahl Hans , Hjemdal Odin 
Published: September 2021

AbstractObjectiveMetacognitive therapy (MCT) and cognitive–behavior therapy (CBT) are effective treatments for generalized anxiety disorder. In this study, we followed‐up patients who had previously participated in a randomized controlled trial of MCT compared against CBT.MethodWe collected 9‐year follow‐up data on 39 out of 60 original patients (i.e., 65% response rate).ResultsAt 9 years, the recovery rates were 57% for MCT and 38% for CBT (completer analysis). Following MCT, 43% maintained their recovery status and a further 14% achieved recovery. Following CBT, the sustained recovery rate was 13%, while a further 25% achieved recovery. Patients in the MCT condition showed significantly more improvement with respect to symptoms of worry and anxiety. In the CBT group, 23.1% were re‐diagnosed with generalized anxiety disorder (GAD) compared with 9.5% in the MCT group.ConclusionsThis follow‐up study showed a continuation of gains in both treatments at long‐term follow‐up, but with outcomes continuing to favor MCT and strengthening its comparative superiority.
Cellulose Depolymerization with LPMO‐inspired Cu Complexes
Authors: Castillo Ivan , Torres‐Flores Andrea P. , Abad‐Aguilar Diego F. , Berlanga‐Vázquez Armando , Orio Maylis , Martínez‐Otero Diego 
Published: September 2021

AbstractBis(benzimidazole)amine‐based copper complexes, with structural similarities to the active sites of Lytic Polysaccharide Monooxygenase enzymes (LPMOs), were tested for the oxidative degradation of cellulose. Spectroscopic characterization of the complexes, as well as structural authentication of one of them, confirm a tetragonal coordination environment with 3 nitrogen donors, as well as a thioether in axial positions. Aqueous oxidative degradation of cellulose was achieved with the CuII complexes and H2O2 as oxidant through putative cupric‐hydroperoxo intermediates. Conversion of cellulose was achieved in up to 67 % yield of soluble oligosaccharide derivatives at ambient temperature and pressure. The products were analyzed in aqueous solution by HPLC‐MS, confirming oxidative depolymerization of cellulose under ambient conditions, in an analogous fashion to LPMOs.
Using Terpene Synthase Plasticity in Catalysis: On the Enzymatic Conversion of Synthetic Farnesyl Diphosphate Analogues
Authors: Hou Anwei , Dickschat Jeroen S. 
Published: September 2021

AbstractFour synthetic farnesyl diphosphate analogues were enzymatically converted with three bacterial sesquiterpene synthases, including β‐himachalene synthase (HcS) and (Z)‐γ‐bisabolene synthase (BbS) from Cryptosporangium arvum, and germacrene A synthase (SmTS6) from Streptomyces mobaraensis. These enzyme reactions not only yielded several previously unknown compounds, showing that this approach opened the door to a new chemical space, but substrates with blocked or altered reactivities also gave interesting insights into the cyclisation mechanisms and the potential to catalyse reactions with different initial cyclisation modes.
Analysis of dynamic topology wireless sensor networks for the internet of things (IoT)
Authors: R Praveen Kumar , Raj Jennifer S. , S Smys 
Published: September 2021

SummaryThe availability of the smart existing systems utilizes the system assets for crucial internet of things (IoT). The IoT visions to develop effectively with the processing model. Past customary versatile figuring set‐ups utilize advanced mobile phones and portables. A sensor could drop out for various reasons, for the system to act naturally adjusting and consider multipath steering. Dynamic topology for a remote sensor arranges all the detecting hubs that are associated together for gathering information that are transmitted. The goals that are accompanying are set for exploring the work that are to be finished. Several sensor hubs in the system are arranged for the improvement of proficiency dynamic topology. The novel strategy has been proposed for the improvement in oneself sorting out, multi‐bounce systems for the remote sensor hubs. Because of its ability to decrease energy utilisation, a cluster‐based model is the best in the remote sensor arrangement. The cluster head selection processes are a lumbering procedure that influences execution on the system execution. Few investigations propose the determination of the cluster head techniques that are being large portion of them that are not fitting for a powerful grouping condition. The calculations for the proposed methodology work better inside a solitary bounce grouping model structure, and the system lifetime establishes a major issue if there should be an occurrence of multi‐jump bunching conditions. The manuscript presents cluster head determination technique novel single‐hop and multi‐hop cluster head selection by GA (S/M HCH‐GA) in wireless sensor networks (WSNs) for both one‐hop as well as multi‐hop cluster models. The technique that is proposed intends to meet the prerequisites of dynamic situations; this is done by choosing cluster head that is dependent on the energy that remains along with the energy that is consumed.
Effect ofAPOEε4 allele on levels of apolipoproteins E, J, and D, and redox signature in circulating extracellular vesicles from cognitively impaired with no dementia participants converted to Alzheimer's disease
Authors: Ben Khedher Mohamed Raâfet , Haddad Mohamed , Laurin Danielle , Ramassamy Charles 
Published: September 2021

AbstractIntroductionThe substantial link between apolipoprotein E (APOE) ε4 allele and oxidative stress may underlie enhanced Alzheimer's disease (AD) risk. Here, we studied the impact ofAPOEε4 on the level of apolipoproteins with antioxidant activities along with oxidative markers in circulating extracellular vesicles (cEVs) and plasma from cognitively impaired‐not demented (CIND) individuals converted to AD (CIND‐AD).MethodsApolipoproteins E, J, and D and antioxidant response markers were determined in cEVs and plasma using immunoblotting, electrochemical examination, and spectrofluorimetry.ResultsTotal antioxidant capacity and apolipoprotein D levels in cEVs, as judged by regression analysis and cognitive performance correlations, allowed us to differentiate CINDAPOEε4 carriers from controls and to predict their progression to AD 5 years later.DiscussionOur findings support the pathological redox linkage betweenAPOEε4 and AD onset and suggest the use of cEVs oxidative signature in early AD diagnosis.
Haemodynamic parameters associated with renal function prior to and following heart transplantation
Authors: Baudry Guillaume , Sebbag Laurent , Bourdin Juliette , Hugon‐Vallet Elisabeth , Jobbe Duval Antoine , Mewton Nathan , Pozzi Matteo , Rossignol Patrick , Girerd Nicolas 
Published: September 2021

AbstractAimsAbnormal renal function is a common feature in patients on heart transplant waiting lists. This study aimed to identify the haemodynamic parameters associated with decreased estimated glomerular filtration rate (eGFR) in patients listed for heart transplantation (HT) and renal function improvement following HT.Methods and resultsA total of 176 adults (52 years old, 81% men) with available right heart catheterization (RHC) listed in our centre for HT between 2014 and 2019 were studied. Cardiac catheterization measurements were obtained at time of HT listing evaluation. Changes in renal function were assessed between RHC and 6 months after HT. Median eGFR was 63 mL/min/1.73 m2 at time of RHC. Central venous pressure > 10 mmHg was associated with a two‐fold increase in the likelihood of eGFR < 60 mL/min/1.73 m2 at time of RHC (adjusted odd ratio, 2.2; 95% confidence interval, 1.1–4.7; P = 0.04). In the 134 patients (76%) who underwent HT during follow‐up, eGFR decreased by 7.9 ± 29.7 mL/min/1.73 m2 from RHC to 6 months after HT. In these patients, low cardiac index (<2.1 L/min/m2) at initial RHC was associated with a (adjusted) 6 month post‐HT eGFR improvement of 12.2 mL/min/1.73 m2 (P = 0.018). Patients with eGFR < 60 mL/min/1.73 m2 and low cardiac index at time of RHC exhibited the greatest eGFR improvement (delta eGFR = 18.3 mL/min/1.73 m2) while patients with eGFR ≥ 60 mL/min/1.73 m2 and normal cardiac index had a marked decrease in eGFR (delta eGFR = −27.7 mL/min/1.73 m2, P < 0.001).ConclusionsCentral venous pressure is the main haemodynamic parameter associated with eGFR < 60 mL/min/1.73 m2 in patients listed for HT. Low cardiac index prior to HT is associated with post‐transplant renal function recovery.
Periprocedural changes in natriuretic peptide levels and clinical outcome after transcatheter mitral valve repair
Authors: Tanaka Tetsu , Kavsur Refik , Spieker Maximilian , Iliadis Christos , Metze Clemens , Horn Patrick , Sugiura Atsushi , Kelm Malte , Baldus Stephan , Nickenig Georg , Westenfeld Ralf , Pfister Roman , Becher Marc Ulrich 
Published: September 2021

AbstractAimsThis multicentre study investigated the association of periprocedural changes in the levels of N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) with clinical outcomes after transcatheter edge‐to‐edge mitral valve repair (TMVR).Methods and resultsPatients were retrospectively analysed who underwent TMVR with the MitraClip system (Abbott Vascular, Santa Clara, CA, USA) and had available sequential NT‐proBNP testing at baseline and 2 months after TMVR. Periprocedural changes in NT‐proBNP following TMVR were assessed as the percent change in NT‐proBNP between baseline and the 2 month follow‐up, and the significant reduction in NT‐proBNP was defined as a decrease of >30% in the follow‐up NT‐proBNP compared with the pre‐procedural NT‐proBNP level. Primary outcome was defined as a composite outcome consisting of all‐cause mortality and hospitalization due to heart failure from 2 months to 2 years after TMVR. Additionally, we identified the cut‐off value of pre‐procedural NT‐proBNP to predict the composite outcome using a receiver operating characteristic analysis (cut‐off: 2485 pg/mL). Of 485 patients undergoing TMVR (age: 76.2 ± 9.2 years, female: 42.1%, secondary mitral regurgitation: 67.2%), 150 patients (30.9%) had the significant reduction in NT‐proBNP (>30%) following the procedure. Patients with the NT‐proBNP reduction had a lower incidence of the composite outcome, compared with those without the reduction in NT‐proBNP (31.4% vs. 40.2%; log‐rank P = 0.03). The significant reduction in NT‐proBNP was also associated with a lower risk of the composite outcome [adjusted hazard ratio (HR): 0.67; 95% confidence interval (CI): 0.45–0.97; P = 0.04], independently of pre‐procedural NT‐proBNP levels and other clinical parameters. The percent change in NT‐proBNP was associated with a linear trend of the incidence of the composite outcome (adjusted HR per 10% decrease: 0.96; 95% CI: 0.94–0.98; P < 0.001). A stratified analysis revealed that the prognostic impact of the significant reduction in NT‐proBNP was consistent among clinical subgroups, including aetiology of mitral regurgitation (P for interaction = 0.99). Higher pre‐procedural NT‐proBNP level (>2485 pg/mL) was associated with the increased risk of the composite outcome (adjusted HR: 1.50; 95% CI: 1.03–2.17; P = 0.03); however, patients with a higher pre‐procedural NT‐proBNP who achieved the significant reduction in NT‐proBNP had a similar risk of the composite outcome to those with a lower pre‐procedural NT‐proBNP.ConclusionsChanges in sequential NT‐proBNP measurements were associated with clinical outcomes within 2 years after TMVR. The assessment of NT‐proBNP dynamics may be valuable to assess the residual risk for patients undergoing TMVR and could assist with post‐procedural management after TMVR.
Multicomponent Domino Approaches for the Synthesis of Spirooxazolidine‐2‐thiones and Spirooxothiolane‐2‐imines
Authors: Reddy Indukuri Divakar , Reddy Potuganti Gal , Maria Cherian Arsha , Babu Nanubolu Jagadeesh , Soujanya Yarasi , Alla Manjula 
Published: September 2021

AbstractA one pot multicomponent protocol is described herein as an approach for construction of spirooxazolidine‐2‐thiones and spirooxothiolane‐2‐imines. In a DBU mediated reaction, isatin, phenyl acetylenes, and aryl isothiocyanates undergo hydrothiolation whereas aliphatic isothiocyanates undergo hydroamination. In the presence of a strong base, NaOH for instance, isothiocyanates are exclusively hydrothiolated. This domino approach proceeds by the addition and 5‐exo dig cyclization via hydroamination/hydrothiolation, involves consecutive C−C,C−O and C−N/C−S bond formations, the reaction pathway is further studied by DFT calculations.
Effect of micropores on the structure and CO2methanation performance of supported Ni/SiO2catalyst
Authors: Shen Liang , Zhu Minghui , Xu Jing 
Published: September 2021

AbstractTwo types of SiO2with different microporosities were evaluated as supports for the Ni/SiO2catalysts. The CO2methanation performance of the catalysts was evaluated, and the structure‐activity relationship was elucidated with thorough characterizations. For the Ni/SiO2catalyst with plenty of micropores, both ultrasmall Ni nanoclusters and larger Ni nanoparticles are present. In contrast, the one with fewer micropores only contains large Ni nanoparticles. During the CO2methanation reaction, CO2can be activated to CO on small Ni nanoclusters and further converted to CH4on larger Ni nanoparticles. Such a tandem catalysis behavior greatly improves the CO2methanation activity. The CH4yield reaches 33.5 μmol·g–1·s–1at 450 °C under 0.1 MPa with a feed H2/CO2mol ratio of 4:1 and a space velocity of 30 L·h–1·g–1. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd.
Neuroimaging measures of iron and gliosis explain memory performance in aging
Authors: Venkatesh Anu , Daugherty Ana M. , Bennett Ilana J. 
Published: September 2021

AbstractEvidence from animal and histological studies has indicated that accumulation of iron in the brain results in reactive gliosis that contributes to cognitive deficits. The current study extends these findings to human cognitive aging and suggests that magnetic resonance imaging (MRI) techniques like quantitative relaxometry can be used to study iron and its effects in vivo. The effects of iron on microstructure and memory performance were examined using a combination of quantitative relaxometry and multicompartment diffusion imaging in 35 young (21.06 ± 2.18 years) and 28 older (72.58 ± 6.47 years) adults, who also completed a memory task. Replicating past work, results revealed age‐related increases in iron content (R2*) and diffusion, and decreases in memory performance. Independent of age group, iron content was significantly related to restricted (intracellular) diffusion in regions with low‐moderate iron (hippocampus, caudate) and to all diffusion metrics in regions with moderate‐high iron (putamen, globus pallidus). This pattern is consistent with different stages of iron‐related gliosis, ranging from astrogliosis that may influence intracellular diffusion to microglial proliferation and increased vascular permeability that may influence all sources of diffusion. Further, hippocampal restricted diffusion was significantly related to memory performance, with a third of this effect related to iron content; consistent with the hypothesis that higher iron‐related astrogliosis in the hippocampus is associated with poorer memory performance. These results demonstrate the sensitivity of MRI to iron‐related gliosis and extend our understanding of its impact on cognition by showing that this relationship also explains individual differences in memory performance.