bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inclusive modelling and parameter estimation of a steam power plant using an LMI‐based unknown input reconstruction algorithm
Authors: Arastou Alireza , Rabieyan Hadi , Karrari Mehdi 
Published: December 2021

AbstractA comprehensive dynamic model of a steam power plant, including turbine, governor, and boiler models, is proposed in this paper. The whole turbine‐boiler control strategies inter alia turbine following, boiler following, coordinated control, and sliding pressure control modes are also taken into account in the modelling procedure, making the integrated model adaptable for all the steam units. A novel multi‐stage algorithm is asserted in the other part of the paper to estimate the obtained model parameters using input‐output data from operational tests. Regarding the fact that the mechanical power as the turbine output and one of the synchronous generator (SG) inputs cannot be measured directly, an efficacious unknown input reconstruction (UIR) method is employed in this paper to determine the mechanical power from SG measured signals. The UIR observer in this method is obtained by solving a linear matrix inequality (LMI). Other parameters are identified by applying a Genetic Algorithm (GA) to the measurement data. Finally, the acquired model and parameters are validated by employing the recorded data from several tests, and the results are discussed.
Investigation of the diffusion and permeation of several media molecules in nano‐sealing composites using molecular dynamics simulation
Authors: Li Kun , Sha Haojie , Gu Boqin 
Published: December 2021

AbstractTo investigate the effect of carbon nanotubes (CNTs) on the sealing performance for nitrile rubber (NBR), a permeability and diffusion model was established that more accurately represented actual sealing. Applying molecular dynamics simulations were conducted, COMPASS force fields were used to calculate the diffusion coefficients, and the mean square displacement values of several molecules in the NBR and its nanocomposites (NBR/CNTs) were calculated. The results showed that the addition of CNTs reduced the diffusion coefficients for small molecules in the NBR materials and improved the sealing performance.
Asymmetrical eleven‐level inverter topology with reduced power semiconductor switches, total standing voltage and cost factor
Authors: Mustafa Uvais , Arif M Saad Bin , Kennel Ralph , Abdelrahem Mohamed 
Published: December 2021

AbstractVoltage source multilevel inverters (MLI) is widely utilized in medium and high‐power applications due to their advantages. Here, an 11‐level, asymmetrical multilevel inverter topology is proposed. The topology utilizes four unidirectional switches, three bidirectional switches along with two dc sources. The proposed configuration of switches and the concept of the dc‐link capacitor is utilized to generate eleven level output voltage. The reduced number of components such as power switches and DC sources, lower control complexity due to capacitors' self‐balancing nature, and low total standing voltage (TSV) are the critical features of the proposed topology. Moreover, a reliability assessment of the topology shows that the topology has a high mean time to fault (MTTF), which makes it robust and reliable. Matlab/Simulink environment is used to develop a simulation model of the proposed topology, while PLECS is used for the thermal modelling and analysis of the converter. A prototype is developed and tested in the laboratory to validate the performance for different loading conditions. The proposed topology can be cascaded to produce the ‘n’ number of levels. The critical comparison of the proposed topology shows that the proposed circuit has advantages over other compared topologies.
Wellenreiten – 12 Monate COVID-19 im Maximalversorger
Authors: Fistera David , Pabst Dirk , Falk Maximilian , Anastasiou Olympia E. , Goer Stefan , Dolff Sebastian , Konik Margarethe , Herbstreit Frank , Taube Christian , Kill Clemens , Risse Joachim 
Published: December 2021

Zusammenfassung
Einleitung Mit weit mehr als 1400 stationär behandelten COVID-19-Patienten ist die Universitätsmedizin Essen der größte COVID-19-Versorger der Region Rhein-Ruhr. Wir präsentieren die Daten unserer Patienten aus den ersten 12 Monaten der Pandemie und die hieraus entstandenen praktischen Konzepte.
Methode Retrospektive Analyse aller 1396 stationären COVID-19-Patienten, die zwischen dem 1. März 2020 und 28. Februar 2021 versorgt wurden, im Hinblick auf Komorbiditäten, Überleben und Komplikationen im Verlauf. Es erfolgte ein Gruppenvergleich zwischen Patienten auf Normalstation und Überwachungs-/ Intensivstation.
Ergebnisse Bei einer Gesamtmortalität von 19,8 % (277/1396) starben 10,6 % (93/877) der Patienten auf Normalstation und 35,5 % (184/519) der Patienten auf Intensiv- und Überwachungsstationen im klinischen Verlauf. Hierbei waren ein Alter über 60 Jahre, Adipositas, maschinelle Beatmung, NO-Therapie, ECMO-Therapie sowie akutes Nierenversagen und Apoplex im Therapieverlauf unabhängige Prädiktoren für Mortalität.
Fazit Die Mortalität unseres Kollektivs auf Normal- bzw. Intensivstationen liegt im Rahmen international publizierter Daten. Sowohl die hohe Rate von Komplikationen bei schwerem Verlauf als auch die große Bedeutung einfacher Komorbiditäten kann eindrücklich gezeigt werden. Das mittlere Alter der Patienten ist mit 60 Jahren auf Normalstation und 63 Jahren auf Intensivstationen überraschend niedrig. Maximaler Patienten- und Personalschutz, eine rasche und effektive Teststrategie im Rahmen der primären Triage, standardisierte Abläufe von der Notaufnahme bis zur Intensivstation sowie eine dynamische tagesaktuelle Anpassung der Ressourcen können eine hohe Versorgungsqualität, auch während der Pandemie, sichern.
Antimicrobial Formulation of Chrysopogon zizanioides Essential Oil in an Emulsified Lotion for Acne
Authors: Kurrimboccus Fadilah , Orchard Ané , Danckwerts Michael Paul , van Vuuren Sandy 
Published: December 2021

AbstractAcne is a skin condition arising from excess sebum production and microbial overgrowth within the pilosebaceous unit. Several commercial essential oils have shown promising activity against acne-related pathogens. Due to their volatility and thermal instability, the formulation of essential oils into commercial products remains a pharmaceutical challenge. Thus, this study aimed to develop a viable anti-acne topical treatment as an oil-in-water emulsified lotion to overcome these challenges. Chrysopogon zizanioides (vetiver) displayed noteworthy antimicrobial activity with a mean minimum inhibitory concentration of 0.14 mg/mL against Cutibacterium acnes, Staphylococcus aureus, Staphylococcus epidermidis, and Streptococcus pyogenes. Emulsified lotions containing C. zizanioides were developed through the hydrophilic-lipophilic balance approach. At tested hydrophilic-lipophilic balance values of 8, 9, and 10, C. zizanioides emulsified
lotions displayed maximum stability at hydrophilic-lipophilic balance 9 with a minimum change in mean droplet size and polydispersity index of 20.61 and 33.33%, respectively, over 84 days. The C. zizanioides emulsified lotion at optimum hydrophilic-lipophilic balance 9 completely inhibited the growth of C. acnes and killed S. aureus, S. epidermidis, and S. pyogenes within 24 h. Additionally, the lotion retained antimicrobial activity against these test micro-organisms over the 84-day stability test period. Thus, the C. zizanioides emulsified lotion demonstrated physical stability and antimicrobial efficiency, making it an ideal natural product anti-acne treatment.
Impact of the COVID 19 Pandemic on Radiological Imaging in Germany
Authors: Schmidbauer Martina , Grenacher Lars , Juchems Markus S. , Memmel Erik , Lauenstein Thomas , Schreyer Andreas G. , Verloh Niklas , Becker Claus , Vogl Thomas J. , Wessling Johannes , Wacker Frank K. , Ringe Kristina Imeen 
Published: December 2021

Purpose To analyze the impact of the COVID-19 pandemic in 2020 on the radiological imaging volume in Germany.
Materials und Methods In this retrospective multicenter study, we analyzed CT and MRI examinations of 7 radiology institutes across Germany from January to December 2020. The imaging volume was compared to 2019 (Wilcoxon-Mann-Whitney test). Modality, patient service locations, and examined body parts were assessed in consideration of time periods of the pandemic. In addition, correlation with the incidence of SARS-CoV-2 cases and associated death was performed (Spearman-test).
Results In total, in 2020, imaging volume declined by 4 % (n = 8314) compared with 2019 (p < 0.05). The hard lockdown during the first pandemic wave (calendar week 12–16, March 22 – April 19) revealed the highest decrease with 29 % (n = 894, p < 0.01), with the greatest decrease in CT (36 % vs. MRI 26 %), outpatients (38 %, p < 0.01), and imaging of the spine and extremities (51–72 %, < 0.05 – p < 0.01). Examinations referred from the emergency department (–13 %, p < 0.05) and CT of the chest (–16 %, p < 0.05) were least affected. With the end of the first wave, gradual normalization of the imaging volume was observed and persisted until the end of the observation period. A reduction of imaging volume negatively correlated with the incidence of SARS-CoV-2-positive cases and associated deaths (r = 0.28 and 0.49, p < 0.05 and p < 0.001).
Conclusion The COVID-19 pandemic was associated with a significant temporary decline in imaging volume. After the first lockdown period, a quick recovery was observed with radiologic imaging examinations steadily approaching prior-year figures.
Key points:
Citation Format
Cytochalasan Alkaloids as TRAIL Sensitizers from an Endophytic Fungus
Chaetomium sp.
Authors: Gao Ying , Mao Ruihua , Liu Ye , Zhou Ming , Ruan Hanli 
Published: December 2021

AbstractTwo new cytochalasans with a rare 6/6/5/5/7 pentacyclic ring system, named
chaetoconvosins C−D (1−2), together with two known congeners
(3−4), were isolated from the fermentation of an endophytic
fungus, Chaetomium sp. SG-01, harbored in the fibrous roots of
Schisandra glaucescens Diels. Their structures including the absolute
configuration were elucidated by extensive spectroscopic (HRESIMS, NMR, and ECD)
and X-ray crystallographic analyses. The TRAIL-resistance-overcoming activity of
1–4 in a TRAIL-resistant HT29 colorectal cancer cell line was
evaluated, which revealed that co-treatment of 1–4 at 50 µM
with TRAIL (150 ng/mL) reduced the HT29 cell viability by 19.0%, 24.1%, 17.9%,
and 15.5%, respectively, compared to treatment with 1–4 alone.
Computed Tomography–Guided Microcoil Localization of Pulmonary Nodules: Effects of Multiple Punctures
Authors: Tian Ye , An Jianli , Zou Zibo , Dong Yanchao , Wu Jingpeng , Chen Zhuo , Niu Hongtao 
Published: December 2021

Abstract
Background The aim of the study is to analyze the effect of multiple punctures in computed tomography (CT)-guided microcoil localization of pulmonary nodules with other risk factors for common complications.
Methods Consecutive patients who underwent CT-guided microcoil localization and subsequent video-assisted thoracoscopic surgery (VATS) between January 2020 and February 2021 were enrolled. Nodules successfully located after only one puncture were defined as the single puncture group, and nodules requiring two or more punctures were defined as the multiple puncture group. Binary logistic regression analysis was performed to assess the relationship between the number of punctures and pneumothorax and intrapulmonary hemorrhage.
Results A total of 121 patients were included. There were 98 (68.1%) pulmonary nodules in the single puncture group compared with 46 (31.9%) nodules in the multiple puncture group. The frequencies of pneumothorax and intrapulmonary hemorrhage were higher in the multiple puncture group than in the single puncture group (p = 0.019 and <0.001, respectively). Binary logistic regression demonstrated that independent risk factors for developing pneumothorax included lateral positioning of the patient (p < .001) and prone positioning (p = 0.014), as well as multiple punctures (p = 0.013). Independent risk factors for intrapulmonary hemorrhage included the distance between the distal end of the coil and the surface of the pleura (p = 0.033), multiple punctures (p = 0.003), and passage through the pulmonary vasculature (p < 0.001).
Conclusion Multiple punctures resulted in an increased incidence of pneumothorax and intrapulmonary hemorrhage compared with single puncture during CT-guided microcoil localization of pulmonary nodules and were independently associated with both pneumothorax and intrapulmonary hemorrhage.
Long-Term Follow-up from the Treatment and Crossover Arms of a Randomized Controlled Trial of an Absorbable Nasal Implant for Dynamic Nasal Valve Collapse
Authors: Bikhazi Nadim , Ow Randall A. , O'Malley Ellen M. , Perkins Nora , Sidle Douglas M. , Stolovitzky Pablo 
Published: December 2021

AbstractWe report the long-term safety and efficacy outcomes of the treatment and crossover arms of a randomized controlled trial evaluating an absorbable nasal implant to address dynamic nasal valve collapse. Participants were adults with severe/extreme nasal airway obstruction primarily due to nasal valve insufficiency who had implant placement. Follow-up visits were at 3, 6, 12, 18, and 24 months post implant. Visits included collection of the following patient-reported outcome measures: nasal obstructive symptom evaluation (NOSE), nasal obstruction visual analog scale (VAS), and the Epworth Sleepiness Scale (ESS). Adverse events were evaluated at each visit. One-hundred-eleven participants with implants were followed. Of the 111, 90 completed the 12-month visit and 70 completed the 24-month visit. NOSE responder rates are greater than 80% at all follow-ups through 24 months. Mean reduction from baseline in NOSE scores is ≥30 points and statistically significant (p <0.001) at all time points through 24 months. Mean VAS score reduction is ≥29.7 points and statistically significant (p <0.001) at all time points. The subgroup of participants with baseline ESS values >10 experienced statistically significant (p <0.001) and clinically meaningful reductions at all postimplant periods, suggesting that the reduction in nasal symptoms may reduce daytime sleepiness for patients who have problems with sleep quality. No serious device-/procedure-related adverse events were reported. Implant migration/retrieval rate was 4.5% (10/222) of total implants or 9% of participants (10/111). The implant is safe and effective for dynamic nasal valve collapse in patients with severe/extreme nasal obstruction and provides durable symptom improvement 24 months after placement.
Factors Related to the Delayed Cure of Hemifacial Spasm after Microvascular Decompression: An Analysis of 175 Consecutive Patients
Authors: Sato Yosuke , Shimizu Katsuyoshi , Iizuka Kazuki , Irie Ryo , Matsumoto Masaki , Mizutani Tohru 
Published: December 2021

AbstractDetailed studies assessing the factors related to delayed cure of hemifacial spasm (HFS) after microvascular decompression (MVD) are sparse. We aimed to evaluate the effect of 11 clinical factors on the time until the patient became spasm free after MVD. We enrolled 175 consecutive patients with HFS who underwent MVD between 2012 and 2018. The end point was defined as the time point at which the patient became spasm free based on the outpatient interview. Patients were divided into six groups depending on when they became spasm free after the operation, as follows: <7 days (n = 62), 7 days to 1 month (n = 28), 1 to 3 months (n = 38), 3 to 6 months (n = 25), 6 to 12 months (n = 17), and >12 months (n = 5). The median time to become spasm free after MVD was 30.0 days. Association of 11 factors (age, sex, laterality, number of offending arteries, vertebral artery compression, number of compression sites, compression at root detachment zone, preoperative Botox treatment, indentation of the brain stem on preoperative magnetic resonance image, transposition, and interposition) with spasm-free rate was assessed using the Cox's proportional hazards model. Spasm-free rate curve after MVD for the significant factor was obtained using the Kaplan–Meier method. In univariate and multivariate analyses, nontransposition was significantly related to delayed HFS cure after MVD (hazard ratio [HR], 0.60; 95% confidence interval [CI], 0.42, 0.87; p = 0.0068 and HR, 0.60; CI, 0.43, 0.85; p = 0.042, respectively). The spasm-free rate was higher in the transposition than in the nontransposition group (p = 0.0013). As shortening the time until spasm free after MVD improves patients' quality of life, transposition should be recommended. Prediction of spasm-free time could relieve the anxiety of postoperative patients.
Carbon nanotube/glycerol embedded low cost flexible sensor for large deflection sensing of continuum manipulators
Authors: Bhattacherjee Saptak , Chatterjee Sananda , Bhaumik Subhasis 
Published: December 2021

Abstract
Large deflection sensing is highly crucial for proper positioning and control of continuum robots during robot assisted minimally invasive surgery (MIS). Existing techniques suffer from eletromagnetic noise susceptibility, harmful radiation exposure, limited range, bio-incompatibility and necessity of expensive instruments. In the present study, we propose a multi-walled carbon nanotubes/polyglycerol based low cost, flexible and biocompatible sensor which could allow safer, faster and accurate angular deflection measurement of continuum robots for biomedical applications. Experimental results demonstrate that the sensor is stretchable up to 100%, provides a gauge factor up to 11.65, have response time around 8 ms, durability of −0.14% for cyclic loading and unloading and show very small creep up to

±
0.0008

(
±
2.88
%
)

. Furthermore, the sensor can measure continuum robot deflection up to

±

150

∘

with a sensitivity of 666.67 ohms/degree, with a maximum error of 1.67% and maximum hysteresis of 1.41%. Thus, wide range, low cost, fast response, and biocompatibility justify the potential of the proposed sensor for large deflection sensing of continuum robots during robot assisted MIS.
Targeted drug delivery vehicles mediated by nanocarriers and aptamers for posterior eye disease therapeutics: barriers, recent advances and potential opportunities
Authors: Zhang Tingting , Jin Xin , Zhang Nan , Jiao Xinyi , Ma Yuanyuan , Liu Rui , Liu Boshi , Li Zheng 
Published: December 2021

Abstract
Nanomedicine and aptamer have excellent potential in giving play to passive and active targeting respectively, which are considered to be effective strategies in the retro-ocular drug delivery system. The presence of closely adjoined tissue structures in the eye makes it difficult to administer the drug in the posterior segment of the eye. The application of nanomedicine could represent a new avenue for the treatment, since it could improve penetration, achieve targeted release, and improve bioavailability. Additionally, a novel type of targeted molecule aptamer with identical objective was proposed. As an emerging molecule, aptamer shows the advantages of penetration, non-toxicity, and high biocompatibility, which make it suitable for ocular drug administration. The purpose of this paper is to summarize the recent studies on the effectiveness of nanoparticles as a drug delivery to the posterior segment of the eye. This paper also creatively looks forward to the possibility of the combined application of nanocarriers and aptamers as a new method of targeted drug delivery system in the field of post-ophthalmic therapy.
‘Why don’t you just tell us what light really is?’ Easy-to-implement teaching materials that link quantum physics to nature of science
Authors: Stadermann Kirsten , Goedhart Martin 
Published: December 2021

Abstract
High school students’ difficulties with quantum physics (QP) are partly due to their limited understanding of the nature of science (NOS). The essence of QP can only be understood with informed views about NOS aspects such as the role of models and the relevance of controversies between physicists. Inversely, QP is an ideal topic for teaching aspects of NOS. However, secondary school textbooks seldom support teachers to explicitly address NOS in QP. Drawing on a five year research program, including observations of students and teachers, we present teaching resources that link NOS aspects with QP. Our materials support active and reflective learning activities, while being adaptable to teachers’ individual needs and affordances. We hope to inspire teachers to address NOS in their QP lessons.
Graphical analysis of the movements of a line-following robot
Authors: Santos Paulo José Sena dos , Vargas Josemar de Siqueira , Cé Amanda Vogel , Perfeito Correia Tiago Fernandes , Dias Weslley de Oliveira , Tiedt Rodrigo Sérgio 
Published: December 2021

Abstract
The difficulties in the interpretation of graphs in kinematics have been studied since the 1980s. To try to reduce students’ learning problems, the researchers point to the need for different didactic strategies, some with the use of new technologies. In this context, we present an experimental proposal that uses a line-following robot based on Arduino to teach graph interpretation in movements with constant velocity.
Biophysical compartment models for single-shell diffusion MRI in the human brain: a model fitting comparison
Authors: Davis Andrew D , Hassel Stefanie , Arnott Stephen R , Hall Geoffrey B , Harris Jacqueline K , Zamyadi Mojdeh , Downar Jonathan , Frey Benicio N , Lam Raymond W , Kennedy Sidney H , Strother Stephen C 
Published: December 2021

Abstract
Clinically oriented studies commonly acquire diffusion MRI (dMRI) data with a single non-zero b-value (i.e. single-shell) and diffusion weighting of b = 1000 s mm−2. To produce microstructural parameter maps, the tensor model is usually used, despite known limitations. Although compartment models have demonstrated improved fits in multi-shell dMRI data, they are rarely used for single-shell parameter maps, where their effectiveness is unclear from the literature. Here, various compartment models combining isotropic balls and symmetric tensors were fitted to single-shell dMRI data to investigate model fitting optimization and extract the most information possible. Full testing was performed in 5 subjects, and 3 subjects with multi-shell data were included for comparison. The results were tested and confirmed in a further 50 subjects. The Markov chain Monte Carlo (MCMC) model fitting technique outperformed non-linear least squares. Using MCMC, the 2-fibre-orientation mono-exponential ball and stick model (

BS

ME

2

) provided artifact-free, stable results, in little processing time. The analogous ball and zeppelin model (

BZ

2

) also produced stable, low-noise parameter maps, though it required much greater computing resources (50 000 burn-in steps). In single-shell data, the gamma-distributed diffusivity ball and stick model (

BS

GD

2

) underperformed relative to other models, despite being an often-used software default. It produced artifacts in the diffusivity maps even with extremely long processing times. Neither increased diffusion weighting nor a greater number of gradient orientations improved

BS

GD

2

fits. In white matter (WM), the tensor produced the best fit as measured by Bayesian information criterion. This result contrasts with studies using multi-shell data. However, in crossing fibre regions the tensor confounded geometric effects with fractional anisotropy (FA): the planar/linear WM FA ratio was 49%, while

BZ

2

and

BS

ME

2

retained 76% and 83% of restricted fraction, respectively. As a result, the

BZ

2

and

BS

ME

2

models are strong candidates to optimize information extraction from single-shell dMRI studies.