bluuebunny/crossref_metadata_2025 huggingface dataset:
The effect of acid treatment and calcination on the modification of zeolite X in diesel fuel hydrodesulphurization
Authors: Karami Hamid , Kazemeini Mohammad , Soltanali Saeed , Rashidzadeh Mehdi
Published: December 2021

Faujasite (X, Y) zeolites are considered the main and important catalysts in hydrorefining processes. In order to obtain zeolites with higher acidity and volume of mesopores, post‐synthesis modification, dealumination by different pickling techniques (using ethylenediamine tetraacetic acid [EDTA] chelating agent), and thermal treatment (calcination) were employed. The dealumination process led to the removal of the aluminum atoms from the zeolite structure and a rise in acidity while maintaining the zeolite crystalline lattice. X‐ray diffraction (XRD), atomic absorption spectrometry (AAS), Fourier‐transform infrared (FT‐IR), field‐emission scanning electron microscopy (FE‐SEM), Brunauer–Emmett–Teller (BET), and temperature‐programmed desorption of ammonia (NH3‐TPD) analyses were performed to study the physicochemical characteristics of the zeolite and catalysts prepared. Atomic absorption spectroscopy showed an increase in the Si/Al ratio in the modified zeolites. Measuring the surface area of zeolite and the volume of the pores through BET‐BJH and t‐plot methods indicated a reduction in the surface area and an increase in the volume of the pores. Under the influence of the dealumination process, the volume of the mesopores in the modified zeolites increased from 0.056 cm3 g−1 in the initial zeolite (Na‐X) to 0.2105 cm3 g−1 (zeolite X1). The acidity of the modified zeolites (X1) increased from 0.32–0.95 mmol NH3/g. The application of the catalysts containing X1 zeolite in the hydrodesulphurization (HDS) process yielded a product with less sulphur (conversion = 87.5%).
Carbon doped selenium electrocatalyst toward CO2 reduction to chemical fuels
Authors: Chanda Debabrata , Basu Suddhasatwa
Published: December 2021

Herein, we demonstrate the catalytic performance of carbon‐doped selenium (C‐Se), prepared by a facile reproducible hydrothermal method, toward electro‐reduction of CO2 (ERC). Here, we adopted two binders, namely Fumion® (anion exchange) and Nafion® (cation exchange) to investigate the catalytic performance and product selectivity in alkaline electrolyte, KHCO3. The C‐Se/Fumion catalysts exhibit superior activity and stability toward ERC compared with C‐Se/Nafion. The main products obtained at a potential range (‐0.9 to ‐1.2 V vs. RHE) of ERC are CH4 and C2H6 for C‐Se/Nafion and CH4 for C‐Se/Fumion. The maximum faradic efficiency of the C‐Se/Nafion for CH4 and C2H6 production are 16.7% and 8.9% and that of the C‐Se/Fumion for CH4 production is 25.5% at ‐1.1 V vs. RHE. The present study reveals the influence of ionic binders on the selectivity of the ERC products.
Optical, anticancer, photoluminescent, and electrochemical properties of crystalline ZnS quantum dots
Authors: Assadullah Insaaf , Bhat Aadil Ahmad , Malik Javied Hamid , Malik Khurshaid Ahmad , Tomar Radha
Published: December 2021

In this study, we report the fabrication of binary chalcogenide zinc sulfide (ZnS) quantum dots (QDs) paying a facial, economical, eco‐friendly, and template‐free chemical method. The as‐synthesized nanomaterial has a single cubic phase; based on its structural features, it was confirmed that the nanoparticles are grown as QDs (2‐10 nm). Morphological studies display the formation of agglomerated QDs (3 nm). The energy‐dispersive spectroscopy shows that the essential elements are in the stoichiometric ratio as in the precursor solutions. Optical properties confirmed that the QDs are suitable for optoelectronic devices revealing room‐temperature photoluminescence. The charge‐storage electrochemical activity was explored via electrochemical characterization performances. Electrochemical studies show that the synthesized material has charge storage ability. And according to the International Commission on Illumination, the ZnS QDs show green emission, thus presenting that the material will be useful for biological applications. In addition, these nanoparticles exhibit incredible anticancer activities especially against breast cancer cells and may be used for biological or biomedical applications as well.
Zircon U–Pb ages of Lohit Plutonic Complex, NE India: Constraints on episodic magmatism of eastern Trans‐Himalaya
Authors: Pebam James , Duraisamy Kamalakannan , Krishna Kalyanam V.S.S. , Sengupta Siladitya , Ghosh Joy Gopal , Kumar Rajeev , Basak Krishnapriya , Guha Dipayan
Published: December 2021

The Lohit Plutonic Complex (LPC) represents Trans‐Himalayan magmatic rocks in the easternmost sector of the Himalayan Orogen. It is divided into leucogranite‐granodiorite‐diorite dominant suite in the NE and the gabbro‐diorite‐granodiorite‐granite–trondhjemite suite in the SE by the Walong Thrust. U–Pb geochronological analyses of euhedral zircon grains from different magmatic phases of LPC reveal episodic magmatism. Zircon U–Pb age of 153.4 ± 1.4 Ma of a garnetiferous granite gneiss suggest that the crustal sourced magmatism was active in Arunachal Trans‐Himalaya during the late Jurassic. U–Pb ages of subduction induced magmatic rocks of LPC range between 117 ± 0.6 Ma and 49.5 ± 0.3 Ma. A significant contribution in crustal recycling during the Oligocene–Miocene is evident from crustally derived leucogranites having U–Pb ages ranging from 35.6 ± 0.3 Ma to 30 ± 0.3 Ma. A comparison of the crystallization ages of the Western Trans‐Himalayan units with those of eastern Trans‐Himalayan units reveals an earlier onset of Tethyan arc magmatism in the eastern sector. The most prominent phase in the eastern sector is during the Late Cretaceous while western and central sector show major activity during the Palaeocene–Eocene.
Elucidating the structural–functional connectome of language in glioma‐induced aphasia using nTMS and DTI
Authors: Zhang Haosu , Ille Sebastian , Sogerer Lisa , Schwendner Maximilian , Schröder Axel , Meyer Bernhard , Wiestler Benedikt , Krieg Sandro M.
Published: December 2021

Glioma‐induced aphasia (GIA) is frequently observed in patients with newly diagnosed gliomas. Previous studies showed an impact of gliomas not only on local brain regions but also on the functionality and structure of brain networks. The current study used navigated transcranial magnetic stimulation (nTMS) to localize language‐related regions and to explore language function at the network level in combination with connectome analysis. Thirty glioma patients without aphasia (NA) and 30 patients with GIA were prospectively enrolled. Tumors were located in the vicinity of arcuate fasciculus‐related cortical and subcortical regions. The visualized ratio (VR) of each tract was calculated based on their respective fractional anisotropy (FA) and maximal FA. Using a thresholding method of each tract at 25% VR and 50% VR, DTI‐based tractography was performed to construct structural brain networks for graph‐based connectome analysis, containing functional data acquired by nTMS. The average degree of left hemispheric networks (Mleft) was higher in the NA group than in the GIA group for both VR thresholds. Differences of global and local efficiency between 25% and 50% VR thresholds were significantly lower in the NA group than in the GIA group. Aphasia levels correlated with connectome properties in Mleft and networks based on positive nTMS mapping regions (Mpos). A more substantial relation to language performance was found in Mpos and Mleft compared to the network of negative mapping regions (Mneg). Gliomas causing deterioration of language are related to various cerebral networks. In NA patients, mainly Mneg was impacted, while Mpos was impacted in GIA patients.
Advances in clinical basic research: Performance, treatments, and mechanisms of Parkinson disease
Authors: Yang Ting‐Ting , Liu Yu‐Cong , Li Jing , Xu Hui‐Chan , Li Shun‐Lian , Xiong Liu‐Lin , Wang Ting‐Hua
Published: December 2021

The loss of neuronal in the substantia nigra of the elderly contributes to striatal damage and plays a critical part in the common forms of neurodegenerative diseases such as Parkinson disease (PD). The deficit of dopamine is one of the most familiar neuropathological features of PD as well as α‐Synuclein aggregation. The peripheral autonomic nervous system is also affected negatively during the course of the disease, although the subsistent of dyskinesias and else major motor characteristic deficits take significant role in the diagnostic methods during clinical practice, which is related to a number of non‐motor symptoms that might increase aggregate risks. Multiple pathways and mechanisms are involved in the molecular pathogenesis: α‐Synuclein, neuronal homeostasis, mitochondrial function, oxidative stress, as well as neuroinflammation. Investigations in the last few years for diagnostic biomarkers used neuroimaging, including single photon emission computed tomography  as well as cutting‐edge magnetic resonance imaging techniques, which has been presented to facilitate discrepant diagnosis. Pharmacological treatment is also important and efficient in equal measure. In addition to reliance on striatal dopamine replacement therapy, many solutions that are used for motor or nonmotor symptoms in these patients are available.
“Just Bring Me Some Books to Read”: Exploring Parental Literacy Narratives Within the Dis/ability Community
Authors: Lampp Berglund Alexandra
Published: December 2021

Parents of individuals with dis/abilities often grapple with their child’s dis/ability, as parents mediate their own experiences surrounding dis/ability. This research specifically investigates the literacy narratives in which parents reveal the literacy tools and practices they engaged with and in to aid in forming their own conceptions of dis/ability. Through narrative inquiry, three interviews with parents of children with dis/abilities were analyzed using postconventional perspectives of dis/ability to highlight the destabilization and multifaceted nature of dis/ability and the dis/ability experience. Findings drawn from parents’ literacy narratives suggest that parents have literacy experiences that stretch well beyond themselves and their immediate families and into the larger dis/ability community. Implications show that more pedagogical and communal resources are needed to support parents within the dis/ability community, as they search for ways to connect with others for emotional and educational purposes.
Ovarian cancer ascites induces skeletal muscle wasting in vitro and reflects sarcopenia in patients
Authors: Ubachs Jorne , van de Worp Wouter R.P.H. , Vaes Rianne D.W. , Pasmans Kenneth , Langen Ramon C. , Meex Ruth C.R. , van Bijnen Annemarie A.J.H.M. , Lambrechts Sandrina , Van Gorp Toon , Kruitwagen Roy F.P.M. , Olde Damink Steven W.M. , Rensen Sander S.
Published: December 2021

Background

Cachexia‐associated skeletal muscle wasting or ‘sarcopenia’ is highly prevalent in ovarian cancer and contributes to poor outcome. Drivers of cachexia‐associated sarcopenia in ovarian cancer remain elusive, underscoring the need for novel and better models to identify tumour factors inducing sarcopenia. We aimed to assess whether factors present in ascites of sarcopenic vs. non‐sarcopenic ovarian cancer patients differentially affect protein metabolism in skeletal muscle cells and to determine if these effects are correlated to cachexia‐related patient characteristics.

Methods

Fifteen patients with an ovarian mass and ascites underwent extensive physical screening focusing on cachexia‐related parameters. Based on computed tomography‐based body composition imaging, six cancer patients were classified as sarcopenic and six were not; three patients with a benign condition served as an additional non‐sarcopenic control group. Ascites was collected, and concentrations of cachexia‐associated factors were assessed by enzyme‐linked immunosorbent assay. Subsequently, ascites was used for in vitro exposure of C2C12 myotubes followed by measurements of protein synthesis and breakdown by radioactive isotope tracing, qPCR‐based analysis of atrophy‐related gene expression, and NF‐κB activity reporter assays.

Results

C2C12 protein synthesis was lower after exposure to ascites from sarcopenic patients (sarcopenia 3.1 ± 0.1 nmol/h/mg protein vs. non‐sarcopenia 5.5 ± 0.2 nmol/h/mg protein, P < 0.01), and protein breakdown rates tended to be higher (sarcopenia 31.2 ± 5.2% vs. non‐sarcopenia 20.9 ± 1.9%, P = 0.08). Ascites did not affect MuRF1, Atrogin‐1, or REDD1 expression of C2C12 myotubes, but NF‐κB activity was specifically increased in cells exposed to ascites from sarcopenic patients (sarcopenia 2.2 ± 0.4‐fold compared with control vs. non‐sarcopenia 1.2 ± 0.2‐fold compared with control, P = 0.01). Protein synthesis and breakdown correlated with NF‐κB activity (rs = −0.60, P = 0.03 and rs = 0.67, P = 0.01, respectively). The skeletal muscle index of the ascites donors was also correlated to both in vitro protein synthesis (rs = 0.70, P = 0.005) and protein breakdown rates (rs = −0.57, P = 0.04).

Conclusions

Ascites of sarcopenic ovarian cancer patients induces pronounced skeletal muscle protein metabolism changes in C2C12 cells that correlate with clinical muscle measures of the patient and that are characteristic of cachexia. The use of ascites offers a new experimental tool to study the impact of both tumour‐derived and systemic factors in various cachexia model systems, enabling identification of novel drivers of tissue wasting in ovarian cancer.
Safe endoscopic removal of ingested fish bone with esophageal perforation and impingement on the aortic wall
Authors: Hoang Van Trung , Van Hoang Anh Thi , Chansomphou Vichit , Vo Uyen Giao
Published: December 2021

Esophageal foreign bodies are common conditions that may lead to serious complications, such as esophageal perforation, neck abscess, mediastinitis, arterial injury, and lung damage. We report a rare case of esophageal fish bone impingement on the aorta that was managed without complication by endoscopic removal.
Mechanisms responsible for interdecadal variation of the thermodynamic component of East Asian summer monsoon moisture transport
Authors: Su Tao , Li Yue , Huang Bicheng , Qu Shulin , Han Zixuan , Qian Zhonghua , Feng Guolin , Wu Yongping
Published: December 2021

In this study, the East Asian summer (June–July–August) monsoon (EASM) atmospheric moisture transport variability under global warming are examined using ERA‐Interim reanalysis data from 1979 to 2019. The total EASM atmospheric moisture transport is decomposed into the thermodynamic (δTH) and dynamic (δMCD) components, which are related to specific humidity and wind velocity, respectively. Based on empirical orthogonal function (EOF) analysis, both the second and the fourth modes of δTH are linked to δMCD, indicating that δMCD can impact the moisture distribution and consequently influence δTH indirectly. Both the first (δTH_EOF1) and the third (δTH_EOF3) modes of δTH show considerable interdecadal changes. It is noted that their principal components exhibit significant increasing trends in recent decades. The response of EASM moisture transport to global warming is probably reflected in these two modes. δTH_EOF1 is associated with negative phases of the Interdecadal Pacific Oscillation (IPO)/Pacific Decadal Oscillation (PDO). This causes the western North Pacific subtropical high (WNPSH) to extend westward and the strengthening of Pacific trade winds. As a result, positive precipitable water anomalies dominate East Asia and δTH_EOF1 is characterized by anomalous southwesterly moisture transport along the East China Sea to southern Japan. δTH_EOF3 corresponds to anomalous moisture transport over the Indochina Peninsula and Japan. The precipitable water associated with δTH_EOF3 in general represents a meridional dipole. Anomalous southward wind induced by the eastward extension of the WNPSH is the main reason for positive (negative) precipitable water anomalies in southern (northern) East Asian. The anomalous circulation associated with the anomalous east–west sea surface temperature gradient over the Indian Ocean affects atmospheric moisture in southern East Asian and can dramatically impact δTH_EOF3.
SEAS5 skilfully predicts late wet‐season precipitation in Central American Dry Corridor excelling in Costa Rica and Nicaragua
Authors: Kowal Katherine M. , Slater Louise J. , Van Loon Anne F. , Birkel Christian
Published: December 2021

Better drought preparedness is critically needed in the Central American Dry Corridor (CADC). Seasonal forecasts can be used to build this preparedness but need localized evaluations to ensure they are relevant and useful. This study provides a CADC‐focused assessment of the SEAS5 seasonal forecasting system produced by the European Centre for Medium‐Range Weather Forecasts (ECMWF). We evaluate SEAS5 predictions of the mean, variability, and extremes of precipitation across the CADC at 1–7‐month lead times. We assess differences in regional forecast quality across seasons and lead times by evaluating spatial and temporal associations with El Niño–Southern Oscillation (ENSO) phase, topography, and continentality. Results show that SEAS5 precipitation forecasts often have better skill primarily during the mid to late wet season (July–October). In these months, low/normal precipitation forecasts outperform the climatological mean (1982–2016) up to 5‐ or 6‐month lead times in some subregions. Forecast skill is often worse, however, for predicting precipitation during the early wet season, primarily in June. Forecast skill varies spatially across the region, with higher skill concentrated in the southeast (Costa Rica and Nicaragua). Forecast skill is significantly related to continentality and topography, and together these factors account for at least a quarter of the spatial variance in annual skill at all lead times. Forecast accuracy varies depending on ENSO phase: predictions are often worse in El Niño (warm ENSO) periods during the early wet season when ENSO also has a weaker association with cumulative precipitation relative to the later wet season. SEAS5 could be a particularly useful tool during the second half of the wet season in the southeast CADC, skilfully alerting of upcoming precipitation variability with over 3‐month lead times.
The Effects of Amniotic Membrane Transplantation on Vocal Fold Regeneration
Authors: Ogawa Machiko , Mukudai Shigeyuki , Sugiyama Yoichiro , Matsushita Hiroki , Kinoshita Shota , Ozawa Satomi , Hashimoto Keiko , Fuse Shinya , Kaneko Mami , Nakanishi Yosuke , Yoshizaki Tomokazu , Sotozono Chie , Hirano Shigeru
Published: December 2021

Objectives/Hypothesis

Vocal fold (VF) scar and sulcus cause severe vocal problems, but optimal methods have not been established. Total replacement of the mucosa is required particularly for cases in which the whole lamina propria is occupied by severe fibrosis and vibratory function is totally lost. The amniotic membrane (AM) has been proven to have regenerative potential, as it contains stem cells and growth factors. The current study investigated the biocompatibility and effects of AM for regeneration of the VF mucosa.

Study Design

In vitro and in vivo studies.

Methods

Vocal fold fibroblasts (VFFs) from 13 Sprague–Dawley rats were seeded on AM and subjected to histology and immunohistochemistry, and gene expressions in the VFFs on AM were examined in in vitro study. Twelve New Zealand White rabbits were used in in vivo study. VFs were stripped down and were reconstructed with AM. The regenerative effects were examined 3 months later by histological examination.

Results

In vitro study indicated VFFs survived on AM and stained positively for Ki67, vimentin, and fibronectin. Gene expressions of Has1, Has2, and Hgf were significantly increased in the VFFs on AM compared with the other groups. The in vivo study indicated AM‐transplanted VFs showed a significantly higher density of hyaluronic acid and lower density of collagen compared with sham VFs.

Conclusions

The current preliminary study suggests biocompatibility and possible regenerative effects of AM for VFs.

Level of Evidence

NA Laryngoscope, 132:2017–2025, 2022
Covalently Cross‐Linked Pig Gastric Mucin Hydrogels Prepared by Radical‐Based Chain‐Growth and Thiol‐ene Mechanisms
Authors: Brand Jessica S. , Forster Leonard , Böck Thomas , Stahlhut Philipp , Teßmar Jörg , Groll Jürgen , Albrecht Krystyna
Published: December 2021

Mucin, a high molecular mass hydrophilic glycoprotein, is the main component of mucus that coats every wet epithelium in animals. It is thus intrinsically biocompatible, and with its protein backbone and the o‐glycosidic bound oligosaccharides, it contains a plethora of functional groups which can be used for further chemical modifications. Here, chain‐growth and step‐growth (thiol‐ene) free‐radical cross‐linked hydrogels prepared from commercially available pig gastric mucin (PGM) are introduced and compared as cost‐efficient and easily accessible alternative to the more broadly applied bovine submaxillary gland mucin. For this, PGM is functionalized with photoreactive acrylate groups or allyl ether moieties, respectively. Whereas homopolymerization of acrylate‐functionalized polymers is performed, for thiol‐ene cross‐linking, the allyl‐ether‐functionalized PGM is cross‐linked with thiol‐functionalized hyaluronic acid. Morphology, mechanical properties, and cell compatibility of both kinds of PGM hydrogels are characterized and compared. Furthermore, the biocompatibility of these hydrogels can be evaluated in cell culture experiments.
A PIAS1 Protective Variant S510G Delays polyQ Disease Onset by Modifying Protein Homeostasis
Authors: Lee Yan Hua , Tsai Yu‐Shuen , Chang Che‐Chang , Ho Chun‐Chen , Shih Hsiu‐Ming , Chen Hui‐Mei , Lai Hsing‐Lin , Lee Chia‐Wei , Lee Yi‐Chung , Liao Yi‐Chu , Yang Ueng‐Cheng , Cheng Tzu‐Hao , Chern Yijuang , Soong Bing‐Wen
Published: December 2021

Background

Polyglutamine (polyQ) diseases are dominant neurodegenerative diseases caused by an expansion of the polyQ‐encoding CAG repeats in the disease‐causing gene. The length of the CAG repeats is the major determiner of the age at onset (AO) of polyQ diseases, including Huntington's disease (HD) and spinocerebellar ataxia type 3 (SCA3).

Objective

We set out to identify common genetic variant(s) that may affect the AO of polyQ diseases.

Methods

Three hundred thirty‐seven patients with HD or SCA3 were enrolled for targeted sequencing of 583 genes implicated in proteinopathies. In total, 16 genes were identified as containing variants that are associated with late AO of polyQ diseases. For validation, we further investigate the variants of PIAS1 because PIAS1 is an E3 SUMO (small ubiquitin‐like modifier) ligase for huntingtin (HTT), the protein linked to HD.

Results

Biochemical analyses revealed that the ability of PIAS1S510G to interact with mutant huntingtin (mHTT) was less than that of PIAS1WT, resulting in lower SUMOylation of mHTT and lower accumulation of insoluble mHTT. Genetic knock‐in of PIAS1S510G in a HD mouse model (R6/2) ameliorated several HD‐like deficits (including shortened life spans, poor grip strength and motor coordination) and reduced neuronal accumulation of mHTT.

Conclusions

Our findings suggest that PIAS1 is a genetic modifier of polyQ diseases. The naturally occurring variant, PIAS1S510G, is associated with late AO in polyQ disease patients and milder disease severity in HD mice. Our study highlights the possibility of targeting PIAS1 or pathways governing protein homeostasis as a disease‐modifying approach for treating patients with HD. © 2021 International Parkinson and Movement Disorder Society
Soft model of solidification with the order–disorder states competition
Authors: Vasin Mikhail , Ankudinov Vladimir
Published: December 2021

A theoretical model is proposed that describes the kinetics of the formation and evolution of competing phases, one of which is a disordered system of topologically stable excitations (vortices) and the second one is an ordered (crystalline) phase. This model is intended to be the simplest model which can demonstrate such important characteristics of solidification process as a sensitivity to the cooling speed, natural appearance of the relaxation times of kinetic phase transformations, and particular features of the rapidly solidified systems. The model was studied numerically showing the crucial properties relevant to the obtained in the experiments on the amorphization in metals. In the present work, we derive a general form of the system's Hamiltonian and stochastic dynamical equations to describe the rapid solidification and a competing formation of amorphous and crystalline phases. The numerical study of the formation of both phases shows the competition of inherited phases during the simultaneous growth from nuclei. The cooling speed has a significant impact on the regimes of the phase formation. We find that solidification during fast cooling leads to the preferred selection of the disordered phase, then the subsequent evolution leads to the aging and to continuous transition to a solid ordered phase. Also, it is shown that further cooling leads to the spinodal decomposition, and the mobility of phases plays a significant role in the dynamics of the defects migration.
Factors associated with timely initiation of antenatal care among pregnant women in Bahir Dar city, Northwest Ethiopia: Cross‐sectional study
Authors: Tesfu Azimeraw Arega , Aweke Amlaku Mulat , Gela Getahun Belay , Wudineh Kihinetu Gelaye , Beyene Fentahun Yenealem
Published: December 2021

Aim

This study aimed to assess the timely initiation of Antenatal Care and associated factors among pregnant women attending antenatal care clinics at Bahir Dar city, North West Ethiopia.

Design

Institutional based cross‐sectional study was conducted.

Methods

Data were collected on 804 pregnant women from 20 February to 27 March 2017. Face‐to‐face interview through systematic sampling technique was applied. Binary logistic regression was performed using SPSS software version 21, and the level of significance of association was determined at p‐value <0.05 with a 95%confidence interval.

Results

This study identified 44.2% of pregnant women started their first antenatal care timely. Maternal secondary and above level of education AOR = 7.07 (95% CI: 4.41, 11.35)), age at first pregnancy >18 years AOR = 2.77 (95% CI: 1.39, 5.57) and having information about the correct time of ANC booking AOR = 3.14 (95% CI: 1.67, 5.92) were significantly associated with timely commencement to first antenatal care.
Modified equation based mesh adaptation algorithm for evolutionary scalar partial differential equations
Authors: Dubey Ritesh Kumar , Mishra Prabhat
Published: December 2021

It is well known that on uniform mesh classical higher order schemes for evolutionary problems yield an oscillatory approximation of the solution containing discontinuity or boundary layers. In this article, an entirely new approach for constructing locally adaptive mesh is given to compute nonoscillatory solution by representative “second” order schemes. This is done using modified equation analysis and a notion of data dependent stability of schemes to identify the solution regions for local mesh adaptation. The proposed algorithm is applied on scalar problems to compute the solution with discontinuity or boundary layer. Presented numerical results show underlying second order schemes approximate discontinuities and boundary layers without spurious oscillations.
Investigation of initiator metal efficiency in the ring‐opening polymerization of lactones: an experimental and computational study
Authors: Gümüştaş Sıla , Balcan Mehmet , Kinal Armağan
Published: December 2021

Poly(δ‐valerolactone) (PVL) was synthesized by ring‐opening polymerization (ROP), employing tin(II) acetate (SnAcet2), lead(II) acetate trihydrate (PbAcet2·3H2O) and cadmium(II) acetate dihydrate (CdAcet2·2H2O) complexes as initiators without any co‐initiator. The highest molecular weight PVL (45 438 g mol−1, 91% yield) was obtained with CdAcet2·2H2O. Characterization of the synthesized products was performed by FTIR, 1H NMR, 13C NMR, gel permeation chromatography (GPC), matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry (MALDI‐TOF/TOF MS), TGA and DSC. Electrostatic data (natural bond orbital and Hirshfeld) and lowest unoccupied molecular orbital (LUMO) of the initiators were obtained by using several density functional theory methods (B3LYP, ωB97X‐D, PBEPBE, BPV86, HSEH1PBE, MPW1PW91, M06 and M062X). In addition, the initiation stage of the ROP mechanism of δ‐valerolactone with these metal acetate complexes was investigated at the ωB97X‐D level with a mixed basis set. It was computationally determined that the most effective initiator was also CdAcet2. The molecular weight variation of PVLs synthesized with these initiators can be associated with the combined evaluation of atomic charge, LUMO and orbital overlap analyses. The computationally obtained reaction barriers for the initiators support this idea, also. In addition, toxicity tests carried out for PVLs synthesized with acetate complexes containing Sn, Cd and Pb revealed that the Sn and Cd complexes do not have a toxic effect on cell viability at some dilution rates. © 2021 Society of Industrial Chemistry.
The mechanism of photoconversion of cyclic dinitrone to oxaziridine and dioxaziridine: A computational investigation of an experimentally reported photochemical reaction
Authors: Sen Sindhuja , Sisodiya Dilawar Singh , Chattopadhyay Anjan
Published: December 2021

The unexplored photochemistry behind the conversion of cyclic dinitrone to oxaziridine and dioxaziridine has been investigated computationally. The mechanism behind the experimentally reported photo‐conversion reaction of 2,2,4,5‐tetramethyl‐2H‐imidazole‐1,3‐dioxide has been analyzed. The allowed S0‐S1 transition in this cyclic dinitrone system is characterized by a transition moment value of 3 Debye. The photo‐excitation to the vertically excited S1 state is subsequently followed by a passage through low‐lying conical intersection(S0/S1). This photoproduct oxaziridine can undergo reverse transformation to the parent dinitrone through a transition state (barrier height 30–40 kcal/mol) with imaginary frequency value close to 1000i cm−1. Under photo‐irradiation, oxaziridine of this dioxide system can undergo strongly allowed singlet‐singlet transition, characterized by HOMO LUMO excitation with transition moment value close to 2.70 Debye. Subsequently, formations of the trans‐ and cis‐dioxaziridines take place through S0/S1 conical intersections.
A semimechanistic population pharmacokinetic and pharmacodynamic model incorporating autoinduction for the dose justification of TAS‐114
Authors: Araki Hikari , Takenaka Toru , Takahashi Koichi , Yamashita Fumiaki , Matsuoka Kazuaki , Yoshisue Kunihiro , Ieiri Ichiro
Published: December 2021

TAS‐114 is a dual deoxyuridine triphosphatase (dUTPase) and dihydropyrimidine dehydrogenase (DPD) inhibitor expected to widen the therapeutic index of capecitabine. Its maximum tolerated dose (MTD) was determined from a safety perspective in a combination study with capecitabine; however, its inhibitory effects on DPD activity were not assessed in the study. The dose justification to select its MTD as the recommended dose in terms of DPD inhibition has been required, but the autoinduction profile of TAS‐114 made it difficult. To this end, an approach using a population pharmacokinetic (PPK)/pharmacodynamic (PD) model incorporating autoinduction was planned; however, the utility of this approach in the dose justification has not been reported. Thus, the aim of this study was to demonstrate the utility of a PPK/PD model incorporating autoinduction in the dose justification via a case study of TAS‐114. Plasma concentrations of TAS‐114 from 185 subjects and those of the endogenous DPD substrate uracil from 24 subjects were used. A two‐compartment model with first‐order absorption with lag time and an enzyme turnover model were selected for the pharmacokinetic (PK) model. Moreover, an indirect response model was selected for the PD model to capture the changes in plasma uracil concentrations. Model‐based simulations provided the dose justification that DPD inhibition by TAS‐114 reached a plateau level at the MTD, whereas exposures of TAS‐114 increased dose dependently. Thus, the utility of a PPK/PD model incorporating autoinduction in the dose justification was demonstrated via this case study of TAS‐114.
Traditional uses, phytochemistry, and pharmacology of genus Vitex (Lamiaceae)
Authors: Das Niranjan , Salgueiro Andréia C. F. , Choudhury Debasish Roy , Mandal Sudip Kumar , Logesh Rajan , Hassan Md. Mahadi , Devkota Hari Prasad
Published: December 2021

Vitex, the genus of the family Lamiaceae, comprises of about 230 species mostly distributed in the warm regions of Europe and temperate regions of Asia. Several Vitex species have been used as folk medicine in different countries for the treatment of various kinds of diseases and ailments. The main aim of this review is to collect and analyze the scientific information available about the Vitex species regarding their chemical constituents and pharmacological activities. The phytochemical investigation of various Vitex species has resulted in the isolation of about 556 chemical constituents belong to various chemical category viz. iridoids, diterpenoids, triterpenoids, flavonoids, lignans, sesquiterpenoids, monoterpenoids, ecdysteroids, and others. The crude extracts of different Vitex species as well as pure phytochemicals exhibited a wide spectrum of in‐vitro and in‐vivo pharmacological activities. In the present review, the scientific literature data on the ethnopharmacological, phytochemical, and pharmacological investigations on the genus Vitex are summarized. More attention should be given in future research to evaluate the pharmacological potential with detailed mechanism of actions for the pure compounds, extracts of plants from this genus. Moreover, their clinical study is needed to justify their use in modern medicine and to further exploring this genus for new drug discovery.
A novel protocol for in‐depth analysis of recombinant adeno‐associated virus capsid proteins using UHPLC–MS/MS
Authors: Zarei Mostafa , Wang Peng , Jonveaux Jérôme , Haller Friedrich M. , Gu Bingnan , Koulov Atanas V. , Jahn Michael
Published: December 2021

Rationale

In‐depth characterization of the three capsid viral proteins (VPs 1, 2, and 3) of adeno‐associated viruses (AAVs) is immediately needed to ensure the consistency in gene therapy products and processes. These proteins are typically present at very low concentrations in matrices containing high concentrations of excipients and salts. Thus, there is a need for convenient methods for sample preparation before proteomic analysis. The aim of this study was to meet this need by developing a fast, reliable approach for isolating VPs in a manner enabling their efficient digestion and in‐depth characterization using liquid chromatography–mass spectrometry (LC–MS).

Methods

VPs from Anc80 were precipitated with different organic solvents, and the resulting precipitates were dissolved in either sodium deoxycholate (SDC) and N‐dodecyl‐beta‐D‐maltoside (DDM) or guanidine hydrochloride (Gu‐HCl). The peptides obtained by the following enzymatic digestion by either trypsin or Asp‐N were analyzed using LC–MS/MS.

Results

We found that precipitation with chloroform/methanol/water results in fast, efficient preparation of VP samples, allowing 100% and 99.2% amino acid sequence coverage of VP1 for trypsin and Asp‐N digestion, respectively. This also allowed complete sequence confirmation of VP1, VP2, and VP3 of Anc80, as well as characterization of the amino acid sequences of the N‐ and C‐terminal regions of each VP, together with their post‐translational modifications (PTMs).

Conclusions

The presented method enables fast, reliable, and relatively cheap sample preparation for identifying AAV serotypes and characterizing the heterogeneity of capsid viral proteins, including their PTMs.
Proof of concept study for using UR10 robot to help total hip replacement
Authors: Walker Peter , Li Tiancheng , Khonasty Richardo , Ponnanna K. M. , Kuo Alexander , Zhao Liang , Huang Shoudong
Published: December 2021

Background

The demand for total hip replacement (THR) for treating osteoarthritis has grown substantially worldwide. The existing robotic systems used in THR are invasive and costly. This study aims to develop a less‐invasive and low‐cost robotic system to assist THR surgery.

Methods

A preliminary robotic reaming system was developed based on a UR10 robot equipped with a reamer to cut acetabulum. A novel approach was proposed to cut through a 5 mm hole in femur such that the operation is less invasive to the patients.

Results

The average error of the cutting hemisphere by the robotic reaming system is 0.1182 mm which is smaller than the average result reaming by hand (0.1301 mm).

Conclusion

The robotic reaming can help make THR procedures less invasive and more accurate. Moreover, the system is expected to be significantly less expensive than the robotic systems available in the market at present.
Distributed adaptive impedance control of networked Lagrangian systems with neighborhood interaction feedback
Authors: Chen Zhenlei , Guo Qing , Li Tieshan , Shi Yan
Published: December 2021

In this study, a new distributed impedance control is proposed in networked Lagrangian systems to improve the compliant performance of each node in respective environment. Different from previous state consensus, this control objective focuses on the dynamic impedance cooperation of networked Lagrangian systems. The augmented impedance error is introduced in the distributed impedance control frame to evaluate the compliant performance of the designed controller. Based on this impedance control frame, the virtual interaction field is proposed to address some typical tasks such that avoid node collision and ensure high cooperation of neighborhood nodes. Then a distributed adaptive impedance controller together with the radial basis function neural network is employed to compensate the model uncertainties of networked Lagrangian systems and guarantee each note convergence to the prescribed dynamic impedance model, which is governed by the robot‐environment interaction. Finally, the comparative simulations have verified the effectiveness of the proposed distributed impedance control method.
Bio‐tillage improves soil physical properties and maize growth in a compacted Vertisol by cover crops
Authors: Zhang Zhongbin , Yan Lei , Wang Yuekai , Ruan Renjie , Xiong Peng , Peng Xinhua
Published: December 2021

Bio‐tillage has recently been proposed as a measure to alleviate soil compaction through biopores created by cover crop roots. The objective of this study was to determine the effect of different cover crops on soil physical properties and the succeeding maize (Zea mays L.) growth in compacted soil. Four treatments, including no cover crop as a control (Con), alfalfa (Medicago sativa L.), oilseed rape (Brassica napus L.), and radish and hairy vetch mixture (Raphanus sativus L. and Vicia villosa Roth), were carried out under both compacted and noncompacted soil conditions. Soil physical properties, such as the volumetric soil water content (SWC), bulk density, saturated hydraulic conductivity (Ks) and air permeability at water potential of −60 hPa (Ka60), and maize root characteristics and yield were measured. The cover crops did not affect the soil bulk density but significantly decreased the SWC in both the compacted and noncompacted soils relative to the Con treatment. The alfalfa treatment presented significantly higher Ks in the noncompacted soil and Ka60 in both the compacted and noncompacted soils than the Con treatment in the soil layer depth of 20–50 cm. The three cover crop treatments improved the maize root biomass density (173.2% for 2018 and 35.6% for 2019) and root length density (50.9% for 2018 and 51.8% for 2019) relative to the Con treatment in the soil layer depth of 10–70 cm in 2018 and soil layer depth of 10–50 cm in 2019 in the compacted soil rather than in the noncompacted soil. Compared with the Con treatment, the radish mixed with hairy vetch treatment in 2018 and the oilseed rape treatment in 2019 significantly enhanced the maize yield in the compacted soil. Our results suggest that alfalfa is the best crop for improving air permeability; however, the oilseed rape and mixture of radish and hairy vetch lead to better maize growth in the compacted soil. Bio‐tillage using cover crops is effective in alleviating soil compaction.
Fast Peel‐Off Ultrathin, Transparent, and Free‐Standing Films Assembled from Low‐Dimensional Materials Using MXene Sacrificial Layers and Produced Bubbles
Authors: Ling Zheng , Wang Fuqiang , Shi Changrui , Wang Zhiyu , Fan Xuanhui , Wang Lu , Zhao Jiafei , Jiang Lanlan , Li Yanghui , Chen Cong , Tang Dawei , Song Yongchen
Published: December 2021

Ultrathin, transparent, and free‐standing films assembled from low‐dimensional nanomaterials (LDMs) are promising for various applications, including transparent heaters and membranes. However, the intact separation of the assembled films, especially those with controlled ultrathin thickness from deposited substrates, is a tremendous challenge, particularly for fast peeling off via self‐detaching. Herein, we propose a versatile method to rapidly peel off ultrathin assembled LDM films, including three types of carbon nanotubes, vermiculite, Ag nanowires, and carbon nanotube@graphene, by dissolving the MXene interlayer from the layer‐by‐layer filtered MXene/LDM Janus films using diluted H2O2. The MXene sacrificial interlayers play dual roles, including physical isolation of LDM films from filter membranes and the production of bubbles that buoy ultrathin LDM films, making them free‐standing. The integrality and self‐detaching rate of the LDM films are determined by the loading and reactivity of the MXene interlayers. The intact LDM films can self‐detach in 80 s by dissolving the optimized MXene interlayer and producing bubbles. The as‐made free‐standing ultrathin LDM films can be transferred to arbitrary substrates and exhibit outstanding performance as transparent heaters. This scalable method provides an efficient and versatile method to produce ultrathin, transparent, and free‐standing LDM films and finds new applications for the growing MXene family.
Evaluation of plasticity‐based concrete constitutive models under monotonic and cyclic loadings
Authors: Gharavi Ali , Asgarpoor Masoumeh , Epackachi Siamak
Published: December 2021

This paper evaluates the applicability of several concrete models to simulate the behavior of concrete elements under monotonic and cyclic loadings. Several robust constitutive models based on the combination of plasticity and continuum damage or plasticity and smeared crack approach are selected. The behavior of one concrete element is evaluated under different uniaxial compression, uniaxial tension, biaxial compression, biaxial tension, biaxial compression–tension, and triaxial compression loads. Then, the applicability of the concrete models is investigated for two flexural beams under cyclic loading. Five concrete models available in the versatile finite element‐based software LS‐DYNA are selected, including Winfrith, CSCM, RHT, KCC, and CDPM. The prepeak, peak, and postpeak behaviors of all selected models are presented, including initial stiffness, peak strength, strain at peak strength, postpeak stiffness, and failure strain.
Validation of cluster analysis results on validation data: A systematic framework
Authors: Ullmann Theresa , Hennig Christian , Boulesteix Anne‐Laure
Published: December 2021

Cluster analysis refers to a wide range of data analytic techniques for class discovery and is popular in many application fields. To assess the quality of a clustering result, different cluster validation procedures have been proposed in the literature. While there is extensive work on classical validation techniques, such as internal and external validation, less attention has been given to validating and replicating a clustering result using a validation dataset. Such a dataset may be part of the original dataset, which is separated before analysis begins, or it could be an independently collected dataset. We present a systematic, structured review of the existing literature about this topic. For this purpose, we outline a formal framework that covers most existing approaches for validating clustering results on validation data. In particular, we review classical validation techniques such as internal and external validation, stability analysis, and visual validation, and show how they can be interpreted in terms of our framework. We define and formalize different types of validation of clustering results on a validation dataset, and give examples of how clustering studies from the applied literature that used a validation dataset can be seen as instances of our framework.

This article is categorized under:

Technologies > Structure Discovery and Clustering

Algorithmic Development > Statistics

Technologies > Machine Learning
Conformally soft fermions
Authors: Pano Yorgo , Pasterski Sabrina , Puhm Andrea
Published: December 2021

Abstract

Celestial diamonds encode the global conformal multiplets of the conformally soft sector, elucidating the role of soft theorems, symmetry generators and Goldstone modes. Upon adding supersymmetry they stack into a pyramid. Here we treat the soft charges associated to the fermionic layers that tie this structure together. This extends the analysis of conformally soft currents for photons and gravitons which have been shown to generate asymptotic symmetries in gauge theory and gravity to infinite-dimensional fermionic symmetries. We construct fermionic charge operators in 2D celestial CFT from a suitable inner product between 4D bulk field operators and spin s = $$ \frac{1}{2} $$

1
2

and $$ \frac{3}{2} $$

3
2

conformal primary wavefunctions with definite SL(2, ℂ) conformal dimension ∆ and spin J where |J| ≤ s. The generator for large supersymmetry transformations is identified as the conformally soft gravitino primary operator with ∆ = $$ \frac{1}{2} $$

1
2

and its shadow with ∆ = $$ \frac{3}{2} $$

3
2

which form the left and right corners of the celestial gravitino diamond. We continue this analysis to the subleading soft gravitino and soft photino which are captured by degenerate celestial diamonds. Despite the absence of a gauge symmetry in these cases, they give rise to conformally soft factorization theorems in celestial amplitudes and complete the celestial pyramid.