bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reaction wheel pendulum control using fourth‐order discontinuous integral algorithm
Authors: Gutiérrez‐Oribio Diego , Mercado‐Uribe Ángel , Moreno Jaime A. , Fridman Leonid 
Published: October 2020

SummaryThe fourth‐order model of the reaction wheel pendulum is considered and a fourth‐order discontinuous integral algorithm is used for stabilization and tracking of the system, using a continuous control signal. The states reach the origin or a reference signal in finite‐time, even in presence of uncertain control coefficient and a kind of matched and unmatched uncertainties/disturbances. A homogeneous Lyapunov function is designed to ensure local finite‐time stability of the system, which can be used for designing the controller gains. Simulations and experimental results illustrate the performance and advantages of the presented algorithm.
Physicochemical Comparison of Chitin Extracted from Horseshoe Crab (Limulus polyphemus) Exoskeleton and Exuviae
Authors: Mendez‐Alpuche A. A. , Ríos‐Soberanis C. R. , Rodriguez‐Laviada J. , Perez‐Pacheco E. , Zaldivar‐Rae J. A. 
Published: October 2020

AbstractIn this paper, horseshoe crab exoskeleton and exuviae were collected on the coasts of Yucatan and physicochemical studies were carried out. Samples from different sections of the exoskeleton were taken to evaluate chitin content and properties in order to be compared with exuviae. The isolation of chitin was realized by chemical processes involving deproteinization, demineralization and discoloration. Physicochemical properties of chitin extracted from both sources were compared in terms of characterization analysis in particular achieved under EDX, FTIR and calorimetric techniques (DSC and TGA). In such comparative analysis lies the importance to establish differences or similitudes in chitin contents, structure, etc. Scanning Electron Microcopy was conducted on exuviae and exoskeleton selected parts in order to identify horseshoe crab structure and surface morphology. Differential scanning calorimetry was focused on changes in physical and chemical structures at different samples showing two endothermic peaks related to the complete elimination of hydroxyl groups attached to polysaccharide rings. TGA thermograms were characterized by endo and exotherms corresponding to water evaporation and decomposition of polymer respectively. Exoskeleton SEM images shown a tubular network and porous surface while exuviae exhibited irregular surface and diatom unicellular microalgae embedded. Calorimetric measurements confirmed that exuviae is richer in chitin than exoskeleton and that the main allotropic crystal structure corresponds to α‐chitin. FTIR analysis supported these results by exhibiting different absorption bands corresponding to α‐chitin.
Kaurenoic Acid Induces Cell Cycle Arrest and Apoptosis in the MCF‐7 Breast Cancer Cell Line
Authors: Roberto de Souza Anderson , Stefany de Souza Castro Mona , Olímpio de Souza Thiago , Cassio Sola Veneziani Rodrigo , Kenupp Bastos Jairo , Ricardo Ambrósio Sérgio , Alves dos Santos Raquel 
Published: October 2020

AbstractBreast cancer continues to be the major cause of cancer death among women. The high genetic heterogeneity and chemoresistant phenotypes of breast tumors require the search for new compounds to expand the options for the treatment of this disease. Kaurenoic acid (KA) is an ent‐kaurane type‐diterpene with cytotoxic and genotoxic effects against gastric and cervical cancer cells. In the present study, we report the antiproliferative effects of KA in the breast tumoral cell line MCF‐7 and the normal breast counterpart MCF‐10 A. The long‐term cytotoxic effects of KA were observed by the reduction of survival fraction at 50 and 100 μM. At these concentrations, the treatment with KA increased the extension of DNA damage followed by G1 cell cycle phase accumulation and induction of apoptosis in both cell lines. Taken together, the results contained herein support the promising antiproliferative effects of KA.
One‐step Preparation of Conducting Polymer/Metal Oxide Doped RGO Trinary Composite for Supercapacitor Applications
Authors: Wadekar Pravin H. , Khose Rahul V. , Pethsangave Dattatray A. , Some Surajit 
Published: October 2020

AbstractA naive one‐pot strategy developed to prepare high‐performance trinary based material as an energy storage material for supercapacitor. Herein, we have systematically studied and established an effortless and proficient synthetic method to formulate reduced graphene oxide (rGO)/polyaniline (PANI)/manganese dioxide (MnO2) (RPM) trinary material in one‐step without any additional oxidizing/polymerizing agent and acidic condition. The approach of “one arrow two targets” have employed to synthesize trinary based nanocomposite. For the first time, we have synthesized this trinary material in one step. Initially, in‐situ synthesized carbonic acid was consumed as a reducing agent to reduce the graphene oxide (GO) as well as it provided acidic condition for the formation of MnO2 and polymerization of aniline. Secondarily, MnO2 particles synthesized from KMnO4 precursor, which acted as an oxidizing agent to polymerize aniline in the presence of carbonic acid. The material reflected the electrical double layer capacitance as well as pseudocapacitance of RGO and PANI/MnO2. The material exhibited the maximum specific capacitance, 592 F/g at 1 A/g current density corresponds to excessive specific energy and specific power 66.6 Wh/kg, 1800 W/kg, respectively. This familiar route of direct production of graphene with the synergism of PANI‐MnO2 on carbon can be useful for large‐scale fabrication of nano‐carbon material for diverse applications including energy storage application.
Improved In Vitro Antimycobacterial Activity of Trinuclear Complexes Cobalt(II,III) and Iron(III) with 2‐Furoic Acid againstMycolicibacterium smegmatis
Authors: Lutsenko Irina A. , Yambulatov Dmitriy S. , Kiskin Mikhail A. , Nelyubina Yulia V. , Primakov Petr V. , Bekker Olga B. , Levitskiy Oleg A. , Magdesieva Tatiana V. , Imshennik Vladimir K. , Maksimov Yurii V. , Sidorov Aleksey A. , Danilenko Valery N. , Eremenko Igor L. 
Published: October 2020

AbstractThe reaction of cobalt(II) and iron(III) pivalates with anions of 2‐furancarboxylic acid (pyromucic acid, Hfur) yielded trinuclear homometallic complexes with linear ([Co3(fur)6(phen)2] (1, phen=1,10‐phenanthroline)) and triangular ([Co3O(fur)6(H2O)3] (3), [Fe3O(fur)6(THF)3] ⋅ 3THF (4)) structures of the metal moiety. The hexanuclear mixed carboxylate cobalt complex [Co6(piv)8(Hpiv)4(fur)2(OH)2] (2, piv−=(CH3)3COO−) was isolated as an intermediate in the synthesis of3. According to CVA data, complex3contains bivalent and trivalent cobalt ions. According to Mossbauer spectroscopy data, all the iron(III) atoms in4, which is an isostructural analogue of3, are solely in the high‐spin state. The antibacterial activity of compounds1–4, K(fur) (5) and Na(fur) (6) was determined in vitro against a non‐pathogenicMycolicibacterium smegmatisstrain. The results of in vitro biological tests againstMycolicibacterium smegmatisshowed a high bioactivity of complexes1and4.
Asymmetric Hydrogenation of Acetophenone Catalyzed by Chirally Modified Ruthenium Nanoparticles Supported on Carbon Nanotubes
Authors: Lv Bolin , Lei Chen , Ren Fupeng , Wang Mingming , Hua Fenglin , Meng Shuangyan , Yang Yaoxia , Yang Zhiwang , Lei Ziqiang 
Published: October 2020

AbstractDifferent types of carbon nanotubes as carriers were used to prepare ruthenium nano‐catalysts loaded outside (named as Ru/CNTs) and inside (named as Ru@CNTs) the tube. The catalysts were modified in situ with chiral ligands (1S, 2S)‐DPEN (1S, 2S)‐DPEN=(1S, 2S)‐1,2‐diphenyl‐1,2‐ethanediamine). In the presence of TPP (TPP=triphenylphosphine) as the stabilization, the catalytic asymmetric hydrogenation of acetophenone was carried out with the modified catalysts. A novel approach to prepare the inside‐loaded catalysts of Ru@CNTs was explored in the preparation. The catalyst can efficiently prevent the Ru nanoparticles from oxidizing in the air in this approach. The catalysts were well characterized by means of TEM, XRD, XPS, BET and H2 Pulse Chemisorption. The effect of the diameter of carbon nanotubes on the particle size of ruthenium nanoparticles loaded on the tubes was also well studied. When Ru@CNTs (8 %, S) (“S” abbreviated from “short”, the same below) was used in the asymmetric hydrogenation of acetophenone, 100 % conversion of acetophenone achieved, and the ee value reached 76.4 %. Under the same reaction conditions, 100 % conversion of acetophenone as well as the highest ee value of 80.8 % were obtained when Ru/CNTs (8 %, S) was applied in the reaction.
Studies Towards the Synthesis of Pristinamycin IIA
Authors: Sušnik Peter , Koert Ulrich 
Published: October 2020

AbstractStudies towards a total synthesis of pristinamycin IIA (1) as part of group A streptogramins is described. Stereoselective syntheses of three building blocks A, B and C including the 2,3‐dehydroproline substructure and their assembly into advanced CAB‐precursor molecules for the natural product was achieved. Attempts to close the macrocylic ring at a late stage by Sm2/Barbier or Nozaki‐Hiyama‐Takai‐Kishi‐reaction demonstrate challenges and limitations of this approach.
Non‐Equilibrium Synthesis of Highly Active Nanostructured, Oxygen‐Incorporated Amorphous Molybdenum Sulfide HER Electrocatalyst
Authors: Giuffredi Giorgio , Mezzetti Alessandro , Perego Andrea , Mazzolini Piero , Prato Mirko , Fumagalli Francesco , Lin Yu‐Chuan , Liu Chenze , Ivanov Ilia N. , Belianinov Alex , Colombo Massimo , Divitini Giorgio , Ducati Caterina , Duscher Gerd , Puretzky Alexander A. , Geohegan David B. , Di Fonzo Fabio 
Published: October 2020

AbstractMolybdenum sulfide emerged as promising hydrogen evolution reaction (HER) electrocatalyst thanks to its high intrinsic activity, however its limited active sites exposure and low conductivity hamper its performance. To address these drawbacks, the non‐equilibrium nature of pulsed laser deposition (PLD) is exploited to synthesize self‐supported hierarchical nanoarchitectures by gas phase nucleation and sequential attachment of defective molybdenum sulfide clusters. The physics of the process are studied by in situ diagnostics and correlated to the properties of the resulting electrocatalyst. The as‐synthesized architectures have a disordered nanocrystalline structure, with nanodomains of bent, defective S‐Mo‐S layers embedded in an amorphous matrix, with excess sulfur and segregated molybdenum particles. Oxygen incorporation in this structure fosters the creation of amorphous oxide/oxysulfide nanophases with high electrical conductivity, enabling fast electron transfer to the active sites. The combined effect of the nanocrystalline pristine structure and the surface oxidation enhances the performance leading to small overpotentials, very fast kinetics (35.1 mV dec−1 Tafel slope) and remarkable long‐term stability for continuous operation up to ‐1 A cm−2. This work shows possible new avenues in catalytic design arising from a non‐equilibrium technique as PLD and the importance of structural and chemical control to improve the HER performance of MoS‐based catalysts.
An examination of the features of science fairs that support students' understandings of science and engineering practices
Authors: DeLisi Jacqueline , Kook Janna F. , Levy Abigail Jurist , Fields Erica , Winfield Lukas 
Published: October 2020

AbstractScience fairs have a long history in the United States and internationally. Their implementation varies greatly (Kook et al, 2020), yet few empirical studies have examined the outcomes of these experiences for student learning. Research indicates that authentic scientific inquiry that focus on students' agency in investigations can contribute to students learning (e.g., Houseal, Abd‐El‐Khalick, and Destefano, 2014). However, teachers have been challenged with implementing inquiry‐based investigations (e.g., Anderson, 2007; Harris & Rooks, 2010). As new science standards increase the demand for science investigations in classrooms that afford students opportunities to engage with science and engineering practices (SEPs; NGSS Lead States, 2013), research is needed to understand the role of teachers and how these experiences can contribute to student learning. In this article, we describe the results of a national study that included data from 21 middle school science fairs. Data included observations of 20 science fairs, pre and postscience fair assessment data from 343 sixth grade students, and interviews or focus groups with 131 students, 122 teachers, 16 administrators, and 29 science fair judges. These data enabled the exploration of features of science fairs, including opportunities for students to engage in SEPs and the teachers support for SEPs through the science fair investigations. Findings reveal that science fair implementation varies considerably across schools. HLM analysis indicates that teachers' support for critiquing practices, particularly when it included students' engagement in evaluating the work of their peers, are positively associated with students understandings of SEPs. Qualitative findings highlight the ways in which teachers structured students' experiences and supported their enactment of SEPs as they conducted their science fair investigations.
Incorporating dose–volume histogram parameters of swallowing organs at risk in a videofluoroscopy-based predictive model of radiation-induced dysphagia after head and neck cancer intensity-modulated radiation therapy
Authors: Ursino Stefano , Giuliano Alessia , Martino Fabio Di , Cocuzza Paola , Molinari Alessandro , Stefanelli Antonio , Giusti Patrizia , Aringhieri Giacomo , Morganti Riccardo , Neri Emanuele , Traino Claudio , Paiar Fabiola 
Published: October 2020

Abstract
Purpose
To develop a videofluoroscopy-based predictive model of radiation-induced dysphagia (RID) by incorporating DVH parameters of swallowing organs at risk (SWOARs) in a machine learning analysis.

Methods
Videofluoroscopy (VF) was performed to assess the penetration-aspiration score (P/A) at baseline and at 6 and 12 months after RT. An RID predictive model was developed using dose to nine SWOARs and P/A-VF data at 6 and 12 months after treatment. A total of 72 dosimetric features for each patient were extracted from DVH and analyzed with linear support vector machine classification (SVC), logistic regression classification (LRC), and random forest classification (RFC).

Results
38 patients were evaluable. The relevance of SWOARs DVH features emerged both at 6 months (AUC 0.82 with SVC; 0.80 with LRC; and 0.83 with RFC) and at 12 months (AUC 0.85 with SVC; 0.82 with LRC; and 0.94 with RFC). The SWOARs and the corresponding features with the highest relevance at 6 months resulted as the base of tongue (V65 and Dmean), the superior (Dmean) and medium constrictor muscle (V45, V55; V65; Dmp; Dmean; Dmax and Dmin), and the parotid glands (Dmean and Dmp). On the contrary, the features with the highest relevance at 12 months were the medium (V55; Dmin and Dmean) and inferior constrictor muscles (V55, V65 Dmin and Dmax), the glottis (V55 and Dmax), the cricopharyngeal muscle (Dmax), and the cervical esophagus (Dmax).

Conclusion
We trained and cross-validated an RID predictive model with high discriminative ability at both 6 and 12 months after RT. We expect to improve the predictive power of this model by enlarging the number of training datasets.
Image-based failure detection for material extrusion process using a convolutional neural network
Authors: Kim Hyungjung , Lee Hyunsu , Kim Ji-Soo , Ahn Sung-Hoon 
Published: October 2020

AbstractThe material extrusion (ME) process is one of the most widely used 3D printing processes, especially considering its use of inexpensive materials. However, the error known as the “spaghetti-shape error,” related to filament tangling, is a common problem associated with the ME process. Once occurring, this issue, which consumes both time and materials, requires a restart of the entire process. In order to prevent this, the user must constantly monitor the process. In this research, a failure detection method which uses a webcam and deep learning is developed for the ME process. The webcam captures images and then analyzes them by machine learning based on a convolutional neural network (CNN), showing outstanding performance in both image classification and the recognition of objects. Sample images were trained based on a modified Visual Geometry Group Network (VGGNet) model and the trained model was evaluated, resulting in 97% accuracy. The pre-trained model was tested on a 3D printer monitoring system for its ability to recognize the “spaghetti-shape-error” and was able to detect 96% of abnormal deposition processes. The proposed method can analyze the ME process in real time and informs the user or halts the process when abnormal printing is detected.
Chronic nonbacterial osteomyelitis — clinical and magnetic resonance imaging features
Authors: d’Angelo Paola , de Horatio Laura Tanturri , Toma Paolo , Ording Müller Lil-Sofie , Avenarius Derk , von Brandis Elisabeth , Zadig Pia , Casazza Ines , Pardeo Manuela , Pires-Marafon Denise , Capponi Martina , Insalaco Antonella , Fabrizio Benedetti , Rosendahl Karen 
Published: October 2020

Abstract
Background
Chronic nonbacterial osteomyelitis (CNO) is a rare autoinflammatory bone disorder. Little information exists on the use of imaging techniques in CNO.

Materials and methods
We retrospectively reviewed clinical and MRI findings in children diagnosed with CNO between 2012 and 2018. Criteria for CNO included unifocal or multifocal inflammatory bone lesions, symptom duration >6 weeks and exclusion of infections and malignancy. All children had an MRI (1.5 tesla) performed at the time of diagnosis; 68 of these examinations were whole-body MRIs including coronal short tau inversion recovery sequences, with additional sequences in equivocal cases.

Results
We included 75 children (26 boys, or 34.7%), with mean age 10.5 years (range 0–17 years) at diagnosis. Median time from disease onset to diagnosis was 4 months (range 1.5–72.0 months). Fifty-nine of the 75 (78.7%) children presented with pain, with or without swelling or fever, and 17 (22.7%) presented with back pain alone. Inflammatory markers were raised in 46/75 (61.3%) children. Fifty-four of 75 (72%) had a bone biopsy. Whole-body MRI revealed a median number of 6 involved sites (range 1–27). Five children (6.7%) had unifocal disease. The most commonly affected bones were femur in 46 (61.3%) children, tibia in 48 (64.0%), pelvis in 29 (38.7%) and spine in 20 (26.7%). Except for involvement of the fibula and spine, no statistically significant differences were seen according to gender.

Conclusion
Nearly one-fourth of the children presented with isolated back pain, particularly girls. The most common sites of disease were the femur, tibia and pelvic bones. Increased inflammatory markers seem to predict the number of MRI sites involved.
Faster age-related decline in cardiorespiratory fitness in rheumatoid arthritis patients: an observational study in the Trøndelag Health Study
Authors: Liff Marthe Halsan , Hoff Mari , Wisløff Ulrik , Videm Vibeke 
Published: October 2020

AbstractPrimary aim: Compare change in estimated cardiorespiratory fitness (eCRF change) in rheumatoid arthritis (RA) patients with population-based age- and sex-matched controls during ~ 11-year follow-up and identify variables associated with eCRF change. Secondary aim: Compare eCRF level in RA patients and controls. eCRF change from the second (HUNT2 1995–1997) to the third (HUNT3 2006–2008) surveys of the Norwegian Trøndelag Health Study was compared between RA patients (n = 188) and controls (n = 26,202) attending both surveys. Predictors of eCRF change were identified by Lasso regression followed by multiple linear regression. Mean eCRF level in RA patients (n = 436) and controls (n = 67,910) was compared using age-adjusted linear regression stratified on sex, as well as two-sample t tests including RA patients (n = 432) and controls (n = 59,124) who attended either HUNT2, HUNT3 or both HUNT2 and HUNT3. The mean eCRF decline from HUNT2 to HUNT3 in RA patients was 8.3 mL min−1 kg−1 versus 6.7 mL min−1 kg−1 in controls (p < 0.001). The decline was faster in RA patients and larger with higher baseline age (standardized regression coefficient for RA patients: (− 0.482 × age + 0.044); controls: (− 0.367 × age, p < 0.001). The decline was also associated with smoking, cardiovascular disease, increasing body mass index, asthma, and hypertension. Mean differences in age-adjusted eCRF level for RA patients versus controls (p < 0.001): women HUNT2: − 3.2 mL min−1 kg−1; HUNT3: − 5.0 mL min−1 kg−1; men HUNT2: − 1.8 mL min−1 kg−1; HUNT3: − 4.0 mL min−1 kg−1. Higher age at baseline was associated with faster decline in eCRF. This change was more pronounced in RA patients than controls, indicating a larger negative effect on fitness of aging in RA. RA patients had lower eCRF compared to healthy individuals.
Comparing the adiabatic and isothermal pressure dependence of the index of refraction in a drop-weight apparatus
Authors: Slanina O. , Quabis S. , Derksen S. , Herbst J. , Wynands R. 
Published: October 2020

AbstractWe have investigated the difference between adiabatic and isothermal compression of liquids by an impacting weight, as observed in the resulting change to the index of refraction. The liquids examined were sebacate, glycerol, and water. For practical reasons, sebacate is best suited for the use of a drop-weight apparatus as a metrologically traceable calibration facility for dynamic pressure. We find that its optical properties under adiabatic and isothermal compression can be converted into each other using literature values of its thermodynamic properties. Care has to be taken to avoid cavitation-like effects, an observation that might need to be taken into account for other methods of generating short pressure pulses in the hundreds-of-MPa range.
Oxygen isotopes in ophicalcites: an ever-lasting controversy?
Authors: Bernoulli Daniel , Weissert Helmut 
Published: October 2020

AbstractTectono-sedimentary breccias, known as ophicalcites, overlie serpentinised peridotites at a Jurassic ocean–continent transition along the Penninic-Austroalpine transition in the Eastern Alps of Switzerland. Deformation of the exhumed mantle rocks and breccia formation occurred under decreasing temperatures and along low-angle detachment faults exposing the mantle rocks at the sea floor and was coupled with hydrothermal activity and carbonation of the serpentinites at shallow depth and/or at the sea floor. Carbon isotopes in the ophicalcites persistently show marine values; however, the interpretation of oxygen-isotope values remained controversial: are they related to Jurassic hydrothermal activity or do they reflect Alpine metamorphic overprint? Here we discuss recent interpretations that relate oxygen isotope values measured in ophicalcites exclusively to Jurassic hydrothermal activity; to this end we use data that we earlier obtained along a north–south profile across Graubünden (eastern Switzerland). We revisited the sites of controversial interpretation along a north–south profile in eastern Switzerland. Along this profile, oxygen isotope values in ophicalcites and overlying pelagic sediments, up to 25 my younger than the ophicalcites, show identical values and become systematically lower with increasing Alpine metamorphism; they strongly deviate from values in ophicalcites and pelagic sediments measured along the Mid-Atlantic Ridge or ancient Atlantic ocean-continent transitions as e.g. in the Iberia–Newfoundland transect. The oxygen-isotope values measured in Alpine ophicarbonates thus reflect isotopic resetting during the Alpine orogeny, related to fluid-rock interaction during regional metamorphism. Hydrothermal processes that accompanied the formation of ophicalcites are not disputed; however, they cannot be traced by oxygen isotope geochemistry.