bluuebunny/crossref_metadata_2025 huggingface dataset:
A study on the application of control chart in healthcare
Authors: Seoh Yee Kam , Wong Voon Hee , Zangeneh Sirdari Mahboobeh
Published: January 2021

The most concerning issues in the healthcare system will always be quality control and quality improvement as they are significant to the health condition of the patient. A quality statistical tool such as statistical process control (SPC) charts will be efficient and highly effective in reducing the sources of variation within the healthcare process and in monitoring or controlling improvement of the process. The control chart is a statistical process control methodology designed to evaluate the process improvement or change in the manufacturing industry and is being implemented gradually in the healthcare sector. This will enable healthcare organizations to prevent unnecessary investment or spending in any changes that sound good but do not have any positive impact on real progress or improvement. When there is greater participation of humans in healthcare, the risks of error are also greater. Control charts help determine the source of error by differentiating the common and special cause of variation, each requiring a different response from healthcare management. This paper intends to deliver an overview of SPC theory and to explore the application of SPC charts by presenting a few examples of the implementation of control charts to common issues in the healthcare sector. After a brief overview of SPC in healthcare, the selection and construction of the two widely used control charts (Individuals and Moving Range chart, U chart) were adopted and illustrated by using the example from healthcare.
Change point detection in process control with robust individuals control chart
Authors: Ng Kooi Huat , Ng Kok Haur , Liew Jeng Young
Published: January 2021

It is crucial to realize when a process has changed and to what extent it has changed, then it would certainly ease the task. On occasion that practitioners could determine the time point of the change, they would have a smaller search window to pursue for the special cause. As a result, the special cause can be discovered quicker and the necessary actions to improve quality can be triggered sooner. In this paper, we had demonstrated the use of so-called exploratory data analysis robust modified individuals control chart incorporating the M-scale estimator and had made some comparisons to the existing charts. The proposed modified robust individuals control chart which incorporates the M-scale estimator in order to compute the process standard deviation offers substantial improvements over the existing median absolute deviation framework. With respect to the application in real data set, the proposed approach appears to perform better than the typical robust control chart, and outperforms other conventional charts particularly in the presence of contamination. Thus, it is for these reasons that the proposed modified robust individuals control chart is preferred especially when there is a possible existence of outliers in data collection process.
Underreporting traffic accidents in Malaysia – a sentiment analysis
Authors: Zamzuri Zamira
Published: January 2021

The underreporting scenario is claimed to be the source of the extra zeros in traffic accident data. This leads to a latter problem in which the fitted statistical model may not be able to produce correct and reliable estimates. Understanding the root of problem as to what is the main cause of the underreporting scenario is essential to assist on the decision making process in traffic accident analysis. In this study, 200 Malaysian drivers were interviewed on their sentiments towards this issue. Their opinions on the causes of underreporting scenario are investigated then assessed using text analyses. First, the Latent Dirichlet Allocation text modelling is employed to find the underlying themes in the reasons of not reporting a traffic accident. Then, the polarity of the topics is measured using a lexicon based sentiment analysis. Results showed that majority Malaysian drivers (80.5%) consider that reporting a minor or non-fatality accident is not important and can be neglected. The decision is due to the fact that of complicated and time consuming reporting process. The drivers are also asked on their opinion after the consequences of underreporting are informed to them. The polarity of their answers shifted to more positive in which 71% drivers will report an accident that occur in the future.
Spectral proximal method for solving large scale sparse optimization
Authors: Woo Gillian Yi Han , Sim Hong Seng , Goh Yong Kheng , Leong Wah June
Published: January 2021

In this paper, we propose to use spectral proximal method to solve sparse optimization problems. Sparse optimization refers to an optimization problem involving the ι0 -norm in objective or constraints. The previous research showed that the spectral gradient method is outperformed the other standard unconstrained optimization methods. This is due to spectral gradient method replaced the full rank matrix by a diagonal matrix and the memory decreased from Ο(n2) to Ο(n). Since ι0-norm term is nonconvex and non-smooth, it cannot be solved by standard optimization algorithm. We will solve the ι0 -norm problem with an underdetermined system as its constraint will be considered. Using Lagrange method, this problem is transformed into an unconstrained optimization problem. A new method called spectral proximal method is proposed, which is a combination of proximal method and spectral gradient method. The spectral proximal method is then applied to the ι0-norm unconstrained optimization problem. The programming code will be written in Python to compare the efficiency of the proposed method with some existing methods. The benchmarks of the comparison are based on number of iterations, number of functions call and the computational time. Theoretically, the proposed method requires less storage and less computational time.
Stability of neutral delay differential equations with applications in a model of human balancing
Authors: Domoshnitsky Alexander , Levi Shai , Kappel Ron Hay , Litsyn Elena , Yavich Roman
Published: January 2021

In this paper the exponential stability of linear neutral second order differential equations is studied. In contrast with many other works, coefficients and delays in our equations can be variable. The neutral term makes this object essentially more complicated for the study. A new method for the study of stability of neutral equation based on an idea of the Azbelev W-transform has been proposed. An application to stabilization in a model of human balancing has been described. New stability tests in explicit form are proposed.
Memory effects on the proliferative function in the cycle-specific of chemotherapy
Authors: Ahmed Najma , Vieru Dumitru , Zaman F.D.
Published: January 2021

A generalized mathematical model of the breast and ovarian cancer is developed by considering the fractional differential equations with Caputo time-fractional derivatives. The use of the fractional model shows that the time-evolution of the proliferating cell mass, the quiescent cell mass, and the proliferative function are significantly influenced by their history. Even if the classical model, based on the derivative of integer order has been studied in many papers, its analytical solutions are presented in order to make the comparison between the classical model and the fractional model. Using the finite difference method, numerical schemes to the Caputo derivative operator and Riemann-Liouville fractional integral operator are obtained. Numerical solutions to the fractional differential equations of the generalized mathematical model are determined for the chemotherapy scheme based on the function of “on-off” type. Numerical results, obtained with the Mathcad software, are discussed and presented in graphical illustrations. The presence of the fractional order of the time-derivative as a parameter of solutions gives important information regarding the proliferative function, therefore, could give the possible rules for more efficient chemotherapy.
Pharmacokinetic Properties of Moracin C in Mice
Authors: You Byoung Hoon , BasavanaGowda Melanayakanakatte Kuberappa , Lee Jae Un , Chin Young-Won , Choi Won Jun , Choi Young Hee
Published: January 2021

Moracin C from Morus alba fruits, also known as the mulberry, has been proven to exhibit inhibitory activities against lipoxygenase enzymes, TNF-α and interleukin-1β secretion, and proprotein convertase subtilisin/kexin type 9 expression. Despite the various pharmacological activities of moracin C, its pharmacokinetic characteristics have yet to be reported. Here, the pharmacokinetic parameters and tissue distribution of moracin C have been investigated in mice, and the plasma concentration of moracin C with multiple dosage regimens was simulated via pharmacokinetic modeling. Our results showed that moracin C was rapidly and well absorbed in the intestinal tract, and was highly distributed in the gastrointestinal tract, liver, kidneys, and lungs. Moracin C was distributed in the ileum, cecum, colon, and liver at a relatively high concentration compared with its plasma concentration. It was extensively metabolized in the liver and intestine, and its
glucuronidated metabolites were proposed. In addition, the simulated plasma concentrations of moracin C upon multiple treatments (i.e., every 12 and 24 h) were suggested. We suggest that the pharmacokinetic characteristics of moracin C would be helpful to select a disease model for in vivo evaluation. The simulated moracin C concentrations under various dosage regimens also provide helpful knowledge to support its pharmacological effect.
Intradural Spinal Arachnoid Cyst in a Pediatric Patient: A Case Report
Authors: Bedin André , Bizzi Jorge W. J. , Flores Evelise Vieira , Schmitz Fernando dos Anjos , Zanatta Cláudia , da Silva Bianca Brinques
Published: January 2021

The present case reports a 13-year-old patient with an intradural arachnoid cyst, which manifested itself with a sudden loss of strength and sensitivity in the lower and upper limbs and a severe pain in the cervical and thoracic region. On examination, a lesion displayed as an intradural hematoma; however, a laminotomy was performed and it was realized that the lesion was an arachnoid spinal cyst of the cervical-dorsal spine.
Clinical Profile and Predictors of Outcome in Children with Acute Fulminant Myocarditis Receiving Intensive Care: A Single Center Experience
Authors: Jayashree Muralidharan , Patil Manisha , Benakatti Govindappa , Rohit Manoj K. , Singhi Sunit , Bansal Arun , Baranwal Arun , Nallasamy Karthi , Angurana Suresh Kumar
Published: January 2021

Acute myocarditis in children is associated with high morbidity and mortality, with limited data on intravenous immunoglobulin (IVIG) treatment and outcome. Our goal was to describe clinical, treatment profile, and predictors of outcome in children with acute fulminant myocarditis (AFM) receiving intensive care. Case records of 120 children with clinical diagnosis of acute myocarditis from January 2008 to December 2018 were analyzed retrospectively. AFM was seen in 89 (74.2%) children of which nearly two-thirds (54 [60.7%]) were hypotensive at admission. The median (interquartile range [IQR]) ejection fraction on echocardiography was 25 (18.5–36%). Eighty-two children (68.3%) received IVIG. Intensive care needs were mechanical ventilation (n = 71; 59.2%) and inotrope support (n = 89; 74.2%); median inotrope score being 30 (IQR: 20–55). Twenty-one children died (17.5%). Fever (p = 0.004), arrhythmia (p = 0.03), shock (p = 0.015), higher inotrope score (p = 0.0001), need for ventilation (p = 0.025), acidosis (p = 0.013), AKI (p = 0.0001), transaminitis (p = 0.0001), and multiorgan dysfunction (p = 0.0001) were associated with mortality. The mortality was significantly less in IVIG treated group (12.1 vs. 28.9%; p = 0.02). On multiple logistic regression, MODS (p = 0.002) was independent predictor of mortality while IVIG treatment (p = 0.004) was favorably associated with survival. AFM complicated by multiorgan dysfunction carried a poor prognosis. IVIG was associated with survival benefit.
Metastatic Extraskeletal Mesenchymal Chondrosarcoma of the Pancreas: Report of an Unusual Case with Review of Literature
Authors: Shah Saloni Naresh , Parameswaran Ashok , Reddy Prasanna Kumar
Published: January 2021

Extraskeletal mesenchymal chondrosarcoma (ESMC) metastasizing to the pancreas in isolation is a rare occurrence. We report a 49-year-old gentleman who had undergone excision of an ESMC of the thigh in 2009 and presented with sudden onset abdominal pain and icterus in 2019. Radiological imaging revealed calcified mass of the pancreas with multiple nodules with extension into the adipose tissue. Distal pancreatectomy was performed and the pathology revealed a bimorphic tumor composed of undifferentiated round blue cells with abrupt transition to hyaline cartilage, typical of mesenchymal chondrosarcoma. To the best of our knowledge, there are only seven prior cases of metastatic ESMC of the pancreas in the English literature. Surgical intervention appears to be the preferred modality of treatment for metastatic pancreatic tumors. These patients may have long latency period before metastasizing and seem to have a good survival period post excision.
The Utility of Epworth Sleepiness Scale to Screen Moderate and Severe Obstructive Sleep Apnea Preoperatively to Predict Difficult Airway
Authors: Soori Rashmi , D’Sa Ivor , Hosmane Giridhar
Published: January 2021

Introduction Obstructive sleep apnea (OSA) is sleep-disordered breathing characterized by repetitive episodes of partial or complete upper airway collapse in sleep leading to apnea and/or hypopnea, desaturations, sleep disruptions, and cardiovascular changes. OSA is a known cause for difficult airway, especially mask ventilation. Daytime sleepiness is one of the hallmark symptoms of OSA. So, we used the Epworth sleepiness score (ESS) in patients suspected of OSA undergoing a sleep study.

Methods Overall, 44 subjects suspected to have OSA and undergoing polysomnography were included in the study. The socio-demographic details and the complaints were recorded and the Epworth sleepiness questionnaire was administered. The severity of OSA was graded as per the American Academy of Sleep Medicine using the apnea hypopnea index.

Results A total of 44 patients were included in the study. Out of these, 19 were mild, 13 moderate, and 12 severe OSA cases, respectively. ESS of more than 10 showed a positive predictive value of 81.25% and specificity of 85% in screening patients with moderate and severe OSA. But the sensitivity and negative predictive value was only 54.16 and 60.71%, respectively.

Conclusion ESS being a simple questionnaire can be easily used preoperatively. A score of more than 10 effectively diagnoses moderate and severe OSA, but less than 10 cannot rule out OSA
Prostatic Artery Embolization through the Profunda Femoris Artery
Authors: Sajan Abin , Isaacson Ari , Bagla Sandeep
Published: January 2021

An 88-year-old catheter-dependent patient with peripheral vascular disease and benign prostatic hyperplasia was referred for prostatic artery embolization (PAE). Selective angiography of the left internal iliac artery (IIA) revealed a 2.5-cm aneurysm and a single artery comprising the anterior division of the IIA (inferior gluteal artery). No prostatic artery (PA) was identified on the left. Additional angiography of the left external iliac artery (EIA), right IIA, and right EIA did not demonstrate prostatic perfusion. The right profunda femoris artery was then selected given previously reported atherosclerotic collaterals, which revealed an ascending branch of the medial circumflex femoral artery coursing through the upper thigh into the pelvis and reconstituting the right anterior division of the IIA. A 2.4-French microcatheter (Terumo) and 0.018-inch wire (Transcend, Boston Scientific) were used to enter the pelvic vasculature, right PA was identified, and a 2-mm coil was used to perform embolization of a potential nontarget anterior division branch. Embolization of the right PA was then performed with 250-µm particulate and Gelfoam slurry. Two-week follow-up revealed spontaneous voiding and catheter independence.
Thermo emf in a two-dimensional electron-hole system in HgTe quantum wells in the presence of magnetic field. The role of the diffusive and the phonon-drag contributions
Authors: Olshanetsky E. B. , Kvon Z. D. , Gusev G. M. , Entin M. V. , Magarill L. I. , Mikhailov N. N.
Published: January 2021

We present an experimental study of the thermo emf of a two-dimensional electron-hole system in a 21 nm HgTe quantum well in the presence of magnetic field. The first experimental observation of Nernst-Ettingshausen effect in a 2D semimetal is reported. The comparison between theory and experiment shows that the thermo emf is determined by two contributions: the diffusion and the phonon drag, with the latter contribution several times greater than the first. The conclusion is drawn about the important role of electron-hole scattering in the formation of both thermoelectric power mechanisms.
Features of the electroresistivity, magnetic and galvanomagnetic characteristics in Co2MeSi Heusler alloys
Authors: Marchenkov V. V. , Perevozchikova Yu. A. , Semiannikova A. A. , Korenistov P. S. , Marchenkova E. B. , Domozhirova A. N.
Published: January 2021

The electro- and magneto-transport as well as magnetic properties of Co2MeSi (Me = Ti, V, Cr, Mn, Fe, Co, Ni) Heusler alloys were studied. The electroresistivity was measured from 4.2 to 300 K, the galvanomagnetic properties (magnetoresistivity and Hall effect) were measured at T = 4.2 K in magnetic fields of up to 100 kOe, and the magnetization at T = 4.2 and 300 K in fields of up to 70 kOe. The normal and anomalous Hall coefficients, saturation magnetization, residual resistivity, current carrier concentration, coefficients at linear contributions into the electroresistivity and magnetoresistivity were obtained. It was shown that on the one hand, there is quite clear correlation between the electronic and magnetic characteristics of Heusler alloys studied, and the spin polarization coefficients of current carriers, taken from well know literature data, on the other hand. The obtained results can be used for creation of new materials for spintronics.
On airborne virus transmission in elevators and confined spaces
Authors: Dbouk Talib , Drikakis Dimitris
Published: January 2021

The impact of air ventilation systems on airborne virus transmission (AVT), and aerosols in general, in confined spaces is not yet understood. The recent pandemic has made it crucial to understand the limitations of ventilation systems regarding AVT. We consider an elevator as a prototypical example of a confined space and show how ventilation designs alone, regardless of cooling or heating, contribute to AVT. Air circulation effects are investigated through multiphase computational fluid dynamics, and the performance of an air purifier in an elevator for reducing AVT is assessed. We have investigated three different flow scenarios regarding the position and operation of inlets and outlets in the elevator and a fourth scenario that includes the operation of the air purifier. The position of the inlets and outlets significantly influences the flow circulation and droplet dispersion. An air purifier does not eliminate airborne transmission. The droplet dispersion is reduced when a pair of an inlet and an outlet is implemented. The overall practical conclusion is that the placement and design of the air purifier and ventilation systems significantly affect the droplet dispersion and AVT. Thus, engineering designs of such systems must take into account the flow dynamics in the confined space the systems will be installed.
First- and second-order crossover between quantum and classical regimes for the escape rate of a nanomagnet manipulated by a Josephson current
Authors: Kim Gwang-Hee
Published: January 2021

Employing the instanton technique and the nonlinear perturbation method, we study quantum-classical escape rate crossover for several forms of magnetic anisotropy in a nanomagnet sandwiched between two superconductors called Josephson φ0 junction. It is shown that the phase boundary separating the first- and second-order crossover is greatly influenced by the bias current as well as the anisotropy constant and the external magnetic field. These features are expected to be observable with existing experimental techniques.
Magnetic and magnetocaloric properties of the nanocrystalline Pr0.7Ba0.2Ca0.1MnO3 sample
Authors: shi Meenak , Bisht Priyanka , Kumar Amit , Mahato Rabindra Nath
Published: January 2021

We have investigated the structural and magnetization properties of the nanocrystalline Pr0.7Ba0.2Ca0.1MnO3 sample, synthesized using the sol–gel method. The Rietveld refinement of the X-ray diffraction pattern of the nanocrystalline sample (recorded at room temperature) confirmed the formation of the orthorhombic crystal structure with Pnma space group. The temperature dependent magnetization M(T) measurements suggested that the present sample undergoes a paramagnetic to ferromagnetic phase transition and the Curie temperature was found to be ∼ 126 K. The positive slopes observed from the Arrott plots for the present sample indicate the second order of magnetic phase transition, as per the Banerjee’s criterion. The maximum value of magnetic entropy change |ΔSMmax| and relative cooling power (RCP) were found to be ∼ 2.2 J kg-1K-1 and 261 Jkg-1 for a magnetic field change of 5 T. The phenomenological universal curve was constructed for the present sample and ΔSM curves were found to collapse into one, and the universal curve confirmed the second order of magnetic phase transition. The relatively large values of |ΔSM| and RCP make the present nanocrystalline compound promising for the magnetic refrigeration technology.
Effects of fuel spatial distribution on wildland fire behaviour
Authors: Atchley Adam L. , Linn Rodman , Jonko Alex , Hoffman Chad , Hyman Jeffrey D. , Pimont Francois , Sieg Carolyn , Middleton Richard S.
Published: January 2021

The distribution of fuels is recognised as a key driver of wildland fire behaviour. However, our understanding of how fuel density heterogeneity affects fire behaviour is limited because of the challenges associated with experiments that isolate fuel heterogeneity from other factors. Advances in fire behaviour modelling and computational resources provide a means to explore fire behaviour responses to fuel heterogeneity. Using an ensemble approach to simulate fire behaviour in a coupled fire–atmosphere model, we systematically tested how fuel density fidelity and heterogeneity shape effective wind characteristics that ultimately affect fire behaviour. Results showed that with increased fuel density fidelity and heterogeneity, fire spread and area burned decreased owing to a combination of fuel discontinuities and increased fine-scale turbulent wind structures that blocked forward fire spread. However, at large characteristic length scales of spatial fuel density, the fire spread and area burned increased because local fuel discontinuity decreased, and wind entrainment into the forest canopy maintained near-surface wind speeds that drove forward fire spread. These results demonstrate the importance of incorporating high-resolution fuel fidelity and heterogeneity information to capture effective wind conditions that improve fire behaviour forecasts.
Annual variation rate of KL-6 for predicting acute exacerbation in patients with rheumatoid arthritis-associated interstitial lung disease
Authors: Tanaka Nozomi , Nishimura Keisuke , Waki Daisuke , Kadoba Keiichiro , Murabe Hiroyuki , Yokota Toshihiko
Published: January 2021

Objectives

This study evaluated the prognostic factors for acute exacerbation (AE), including sequential changes in Krebs von den Lungen-6 (KL-6) levels, in rheumatoid arthritis-associated interstitial lung disease (RA-ILD) patients.

Methods

This was a retrospective observational study. We reviewed 125 patients diagnosed with RA-ILD between 2010 and 2019. We defined ΔKL-6 as the annual variation rate of KL-6 one visit before AE onset (or the last visit). The Cox regression analysis was used for evaluating significant variables associated with AE. We analysed the overall survival and respiratory-related death-free survival.

Results

Thirty-three patients (26.4%) developed AE during the observation period. The univariate analysis revealed that KL-6 levels at RA-ILD diagnosis [hazard ratio (HR), 1.11; 95% confidence interval (CI), 1.05–1.15; p < .01) and ΔKL-6 (HR: 3.69; 95% CI: −1.36 to 7.96; p = .01] were significantly associated with AE. ΔKL-6 was an independent prognostic factor for AE in the multivariate analysis (HR: 3.37; 95% CI: −1.16 to 8.87; p = .03). Patients with AE had a significantly higher overall mortality rate (p = .02) and respiratory-related mortality rate (p < .01) than those without AE.

Conclusion

ΔKL-6 can be a prognostic marker for detecting AE in RA-ILD patients.
QTc interval prolongation in patients with systemic lupus erythematosus treated with hydroxychloroquine
Authors: Nishiyama Taihei , Kondo Yuya , Tsuboi Hiroto , Noma Hisashi , Tabuchi Daiki , Sugita Toshiki , Okamoto Shota , Terasaki Toshihiko , Shimizu Masaru , Honda Fumika , Ohyama Ayako , Kurata Izumi , Yagishita Mizuki , Abe Saori , Takahashi Hiroyuki , Osada Atsumu , Hagiwara Shinya , Matsumoto Isao , Sumida Takayuki
Published: January 2021

Objectives

The primary objective is to reveal the effect of hydroxychloroquine (HCQ) treatment on corrected QT (QTc) interval in patients with systemic lupus erythematosus (SLE). The secondary objective is to investigate factors that affect QTc prolongation.

Methods

SLE patients who had electrocardiograms between 2015 and 2020 were recruited and assigned to two groups based on whether they were treated with HCQ (HCQ group) or not (control group). Change of QTc before and after HCQ administration in the HCQ group was measured and compared with the control group. Patients treated with HCQ were further divided into two groups based on presence or absence of QTc prolongation and the characteristics were compared.

Results

In total, 126 patients were recruited, of whom 42 were treated with HCQ. In the HCQ group, the mean QTc significantly increased (p < .001), while there was no significant difference of mean QTc in the control group. Moreover, those in the HCQ group with QTc prolongation showed a significantly higher proportion of hypertension and longer SLE duration compared to those without QTc prolongation. However, the multiple logistic regression analysis showed that there were no significant differences among them.

Conclusion

HCQ could induce QTc prolongation in SLE patients. It might be better that the possibility of QTc prolongation was taken into consideration when HCQ was administered in the patients with longer disease duration of SLE and coincidence of hypertension.
Pathogenic mutations in the kinesin-3 motor KIF1A diminish force generation and movement through allosteric mechanisms
Authors: Budaitis Breane G. , Jariwala Shashank , Rao Lu , Yue Yang , Sept David , Verhey Kristen J. , Gennerich Arne
Published: January 2021

The kinesin-3 motor KIF1A functions in neurons, where its fast and superprocessive motility facilitates long-distance transport, but little is known about its force-generating properties. Using optical tweezers, we demonstrate that KIF1A stalls at an opposing load of ~3 pN but more frequently detaches at lower forces. KIF1A rapidly reattaches to the microtubule to resume motion due to its class-specific K-loop, resulting in a unique clustering of force generation events. To test the importance of neck linker docking in KIF1A force generation, we introduced mutations linked to human neurodevelopmental disorders. Molecular dynamics simulations predict that V8M and Y89D mutations impair neck linker docking. Indeed, both mutations dramatically reduce the force generation of KIF1A but not the motor’s ability to rapidly reattach to the microtubule. Although both mutations relieve autoinhibition of the full-length motor, the mutant motors display decreased velocities, run lengths, and landing rates and delayed cargo transport in cells. These results advance our understanding of how mutations in KIF1A can manifest in disease.
Modifying self-sensing cement-based composites through multiscale composition
Authors: Dong Sufen , Zhang Wei , Wang Danna , Wang Xinyue , Han Baoguo
Published: January 2021

This paper aims to develop self-sensing cement-based composites with high sensitivity through building a multiphasic and multiscale conductive network formed by hybrid super-fine stainless steel wires (SSWs) and carbon nanotubes (CNTs)/nano-TiO2 particles (NTs). Experimental results show that 0.15 vol% SSWs are already in the percolation threshold zone, and incorporating CNTs/NTs has a synergistic effect of decreasing the electrical resistivity and increasing the strain sensitivity of cement-based composites under cyclic/monotonic compressive loading. The hybrid modification effect is closely related to the dosage and conductivity of nano-fillers. The sensing mechanisms mainly include the change of capacitance, tunneling resistance between fillers and intrinsic resistivity of fillers. For cement-based composites with 0.3 vol% SSWs, the electrical resistivity and self-sensing properties are primarily dominated by the SSW network, and are barely affected by the addition of CNTs. However, the strain sensitivity corresponding to the maximum absolute value of fractional change in electrical resistivity under monotonic loading is increased by 62.8% and reaches up to 140 as NTs are added, resulting from the semiconductor and nano-core properties of NTs to form a barrier between overlapping SSW conductive networks. It can therefore be concluded that tailoring different conductive networks by incorporating hybrid multiscale and multicharacteristic fillers is an effective method of developing self-sensing cement-based composites with high sensitivity.
A static beam delivery device for fast scanning proton arc-therapy
Authors: Nesteruk K P , Bolsi A , Lomax A J , Meer D , van de Water S , Schippers J M
Published: January 2021

Arc-therapy is a dose delivery technique regularly applied in photon radiation therapy, and is currently subject of great interest for proton therapy as well. In this technique, proton beams are aimed at a tumor from different continuous ranges of incident directions (so called ‘arcs’). This technique can potentially yield a better dose conformity around the tumor and a very low dose in the surrounding healthy tissue. Currently, proton-arc therapy is performed by rotating a proton gantry around the patient, adapting the normally used dose-delivery method to the arc-specific motion of the gantry. Here we present first results from a feasibility study of the conceptual design of a new static fast beam delivery device/system for proton-arc therapy, which could be used instead of a gantry. In this novel concept, the incident angle of proton beams can be set rapidly by only changing field strengths of small magnets. This device eliminates the motion of the heavy gantry and related hardware. Therefore, a reduction of the total treatment time is expected. In the feasibility study presented here, we concentrate on the concept of the beam transport. Based on several simple, but realistic assumptions and approximations, proton tracking calculations were performed in a 3D magnetic field map, to calculate the beam transport in this device and to investigate and address several beam-optics challenges. We propose and simulate corresponding solutions and discuss their outcomes. To enable the implementation of some usually applied techniques in proton therapy, such as pencil beam scanning, energy modulation and beam shaping, we present and discuss our proposals. Here we present the concept of a new idea to perform fast proton arc-scanning and we report on first results of a feasibility study. Based on these results, we propose several options and next steps in the design.
Isovector giant dipole resonances in proton-rich Ar and Ca isotopes *
Authors: Liu Ling , Liu Shuai , Zhang Shi-Sheng , Cao Li-Gang
Published: January 2021

The isovector giant dipole resonances (IVGDR) in proton-rich Ar and Ca isotopes have been systematically investigated using the resonant continuum Hartree-Fock+BCS (HF+BCS) and quasiparticle random phase approximation (QRPA) methods. The Skyrme SLy5 and density-dependent contact pairing interactions are employed in the calculations. In addition to the giant dipole resonances at energy around 18 MeV, pygmy dipole resonances (PDR) are found to be located in the energy region below 12 MeV. The calculated energy-weighted moments of PDR in nuclei close to the proton drip-line exhaust about 4% of the TRK sum rule. The strengths decrease with increasing mass number in each isotopic chain. The transition densities of the PDR states show that motions of protons and neutrons are in phase in the interiors of nuclei, while the protons give the main contribution at the surface. By analyzing the QRPA amplitudes of proton and neutron 2-quasiparticle configurations for a given low-lying state, we find that only a few proton configurations give significant contributions. They contribute about 95% to the total QRPA amplitudes, which indicates that the collectivity of PDR states is not strong in proton-rich nuclei in the present study.
Anisotropic stellar structures in the

theory of gravity with quintessence via embedding approach
Authors: Ditta Allah , Ahmad Mushtaq , Hussain Ibrar , Mustafa G.
Published: January 2021

This work suggests a new model for anisotropic compact stars with quintessence in

gravity by using the off-diagonal tetrad and the power-law as

, where T is the scalar torsion and

and n are real constants. The acquired field equations incorporating the anisotropic matter source along with the quintessence field, in

gravity, are investigated by making use of the specific character of the scalar torsion T for the observed stars

,

,

,

, and

. It is suggested that all the stellar structures under examination are advantageously independent of any central singularity and are stable. Comprehensive graphical analysis shows that various physical features which are crucially important for the emergence of the stellar structures are conferred.
Mid-infrared spectral responsivity scale based on an absolute cryogenic radiometer and a tunable quantum cascade laser
Authors: Liu Wende , Xu Nan , He Yingwei , Gan Haiyong , Feng Guojin , Wang Yanfei , Liu Xiangliang , Fu Yangting , Wang Yingce , Lin Yandong
Published: January 2021

The spectral optical radiant power of a quantum cascade laser (QCL) in the (7.35–10.6) µm spectral range has been measured using a Y-shape absolute cryogenic radiometer (ACR). The spectral responsivity (SR) of a transfer detector based on an integrating-sphere-coupled mercury-cadmium-telluride (IS-MCT) photoconductive detector has been calibrated. The optical radiant power of the QCL can be adjusted and stabilized in the range of (0.035–0.6) mW. The relative uncertainty of the ACR-based optical radiant power measurement was evaluated to be 0.023%–0.04% (k = 1). The relative uncertainty of the SR calibration of the IS-MCT transfer detector was analyzed to be 0.097%–0.16% (k = 1). The spectral range for the SR calibration can be extended to cover (3–12) µm using commercially available QCLs.
Advanced multi-step brazing for fabrication of a divertor heat removal component
Authors: Tokitani M. , Hamaji Y. , Hiraoka Y. , Masuzaki S. , Tamura H. , Noto H. , Tanaka T. , Tsuneyoshi T. , Tsuji Y. , Muroga T. , Sagara A. , Design Group the FFHR
Published: January 2021

The advanced fabrication method named advanced multi-step brazing (AMSB) has been developed for fabrication of a tungsten (W)/copper alloy divertor heat removal component in a fusion reactor. The principle of AMSB is repetitive application of the advanced brazing technique (ABT). The ABT was originally developed in our previous work for jointing of W and oxide dispersion strengthened copper alloy (ODS-Cu: GlidCop®) with the BNi-6 (Ni-11%P) filler material. The special feature of the AMSB is that the leak-tight joint of GlidCop® (GlidCop®/GlidCop®) and of stainless steel (SUS) and GlidCop® (SUS/GlidCop®) can be realized by application of the ABT. Therefore, the AMSB enables production of a leak-tight sealing structure with the appropriate lid material such as GlidCop® or SUS for a pre-processed rectangle-shaped cooling flow path channel. The rectangle-shaped cooling flow path channel has an advantage regarding its heat removal capability. Another special feature of the AMSB is that the physical properties of the AMSB joint has strong tolerance against the repetitive brazing heat cycle. Thus, repetitive application of the ABT does not cause any undesired effects on the leak tightness of the GlidCop®/GlidCop® and the SUS/GlidCop®. The new AMSB type component with the rectangle-shaped fluid flow path and the V-shaped staggered rib structure were successfully produced; therein a pre-processed rectangle-shaped cooling flow path channel was sealed with a GlidCop® and SUS lid structure with leak-tight conditions. The component showed excellent heat removal capability under reactor-relevant conditions with ∼30 MW m−2.
A machine-learning approach to human footprint index estimation with applications to sustainable development
Authors: Keys Patrick W , Barnes Elizabeth A , Carter Neil H
Published: January 2021

The human footprint index (HFI) is an extensively used tool for interpreting the accelerating pressure of humanity on Earth. Up to now, the process of creating the HFI has required significant data and modeling, and updated versions of the index often lag the present day by many years. Here we introduce a near-present, global-scale machine learning-based HFI (ml-HFI) which is capable of routine update using satellite imagery alone. We present the most up-to-date map of the HFI, and document changes in human pressure during the past 20 years (2000–2019). Moreover, we demonstrate its utility as a monitoring tool for the United Nations Sustainable Development Goal 15 (SDG15), ‘Life on Land’, which aims to foster sustainable development while conserving biodiversity. We identify 43 countries that are making progress toward SDG15 while also experiencing increases in their ml-HFI. We examine a subset of these in the context of conservation policies that may or may not enable continued progress toward SDG15. This has immediate policy relevance, since the majority of countries globally are not on track to achieve Goal 15 by the declared deadline of 2030. Moving forward, the ml-HFI may be used for ongoing monitoring and evaluation support toward the twin goals of fostering a thriving society and global Earth system.
Assessment on the impact of FSP process parameters on microstructural, mechanical and wear behaviour of FSPed AA6082
Authors: M Sivanesh Prabhu , Elayaperumal A , Arulvel S , Wasim Khan M
Published: January 2021

The present research work demonstrates the effect of friction stir process (FSP) and its process parameters (rotation speed and travel speed) on the microstructure evaluation, microhardness and wear behaviour of FSPed AA6082. The microstructure characterization of the processed samples was examined using the Optical Microscope (OM). Dry sliding wear test was carried out by varying the sliding velocity (0.5, 0.75 and 1.0 m s−1) and applied load (5, 10 and 15N) using the pin on disc apparatus. Wear mechanisms experienced by the FSPed AA6082 were mapped, and the optimal FSP and wear parameters have been determined using Taguchi analysis. The results showed that there is a significant improvement in the microhardness (92 HV

0.3) and wear resistance for RS 1250 rpm & TS 40 mm min−1 due to the grain strengthening mechanism and microstructure modification. Formation of oxide layer played a crucial role on the wear resistance of the FSPed AA6082 and its significance has been discussed elaborately using the Scanning Electron Microscope (SEM) and Energy Dispersive Spectroscopy (EDS).
Effect of centrifugal casting temperature on the microstructure and properties of ZTAP/HCCI matrix composites
Authors: Niu Ge , Sui Yudong , Zeng Hongbin , He Han , Jiang Yehua , Zhou Mojin
Published: January 2021

In the centrifugal casting process, the casting temperature parameters affected the microstructure characteristics, and the performance of the materials was greatly significant. ZTA (ZrO2 reinforced Al2O3) particles reinforced HCCI (High chromium cast iron) matrix composites with honeycomb structure were obtained by centrifugal casting. With the increased casting temperature (1450 °C, 1500 °C, 1550 °C, and 1600 °C), the austenite equivalent diameter size was 43.5 μm, 34.8 μm, 33.1 μm, 22.3 μm respective in the compound area and 58.3 μm, 63.1 μm, 65.2 μm, 71.5 μm respective in substrate area. The average size of eutectic carbides in the compound area decreased from 5.7 μm to 2.5 μm with the casting temperature increased. Meanwhile, the lattice constants of austenite and carbide increased with the increased temperature. The hardness of the composites increased by 4 ∼ 6HRC with a change in casting temperature. The results of three-body abrasive wear under high-stress static load conditions showed that the wear volume loss of the composites reduced with the temperature increased and the wear resistance was 1.4 times at 1600 °C than that at 1450 °C.
High ionic conductivity of Lu2O3–TiO2 co-doped Bi2O3 ceramics
Authors: Luo Zeyang , Wang Huan , Ma Yuxin , Zhang Guodong , Yan Duanting , Bai Xinyu , Wang Dejun , Liu Runru
Published: January 2021

In this study, a promising electrolyte material Bi0.76Lu0.16Ti0.08O1.5+δ
(abbreviated as ‘8T16LSB’) with high oxygen ion conductivity was obtained by co-doping with Lu2O3 and TiO2 into Bi2O3. The phase composition, microstructure, and conductivity of TLSB ceramics were respectively investigated by x-ray diffraction, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). XRD results exhibited that the sintered TLSB ceramics with an unchanged total doping concentration of 24 mol.% existed as a cubic fluorite structure. SEM results showed that the TLSB pellets were relatively dense. The relationship between temperature and conductivity showed that the 8T16LSB ceramic exhibited the highest conductivity of 0.56 S cm−1 at 700 °C, which was higher than the value of 0.37 S cm−1 for the representative single-doping Er0.4Bi1.6O3 (abbreviated as ‘20ESB’). The results certified that the electrochemical performance of Bi2O3 was promoted by the co-dopant of Lu3+and Ti4+.
Influence of drying methods on the physical properties of bacterial nanocellulose
Authors: Andree Verena , Niopek Daniel , Müller Christine , Eiselt Jan-Philipp , Foh Nina , Rzany Alexander , Hensel Bernhard
Published: January 2021

Bacterial nanocellulose (BNC) is a promising material for the use in medical implants. BNC does not induce unwanted reactions in vivo, is long term stable and possesses unique mechanical properties. However, to make the most of these features, BNC must be carefully processed. Details of the cultivation and post-synthetic methods offer various ways to control the properties of BNC. The focus of this work is put on drying of the BNC. Different unconstrained drying methods (climate chamber at 23°C, oven at 100°C, freeze-drying) and constrained drying under excertion of uniaxial pressure at various temperatures have been investigated. The reduction of the high water content of native BNC (≈98%) causes a thickness reduction of the samples. For oven or climate chamber drying a thickness reduction of 98% is observed, while freeze-drying widely preserves the nano- or micro-structure of the fibrous material and leads to a thickness reduction of only ≈13%. During drying or pressing at high temperature (100°C), i.e. by evaporation of the water, intermolecular hydrogen bonds are formed and interconnect the individual fibres and strands. Consequently mechanical stiffening is observed in tensile tests at small strains. After drying, a densified cellulose nano-fibre network is observed by scanning electron microscopy. Due to the irreversibility of drying by evaporation, the water content and water retention capacity of BNC are not recovered by rehydration. Applying uniaxial pressure before drying further enhances the irreversible reinforcement of the fibre network, while this is not the case when pressing the samples after drying. The presented results show that the properties of BNC can be widely controlled by post-processing steps. Thus, taylor-made BNC can be produced for biomedical applications.
The white light caused by defects and complex cation distribution in ZnAl2-xFexO4 magnetic nanocrystals
Authors: Zhang Dong , Zhu Bingjun , Ren Shiqi , Wang Qingru , Wang Qinglin , Li Shuhong , Zhang Bingyuan , Wang Wenjun
Published: January 2021

ZnAl2O4 with spinel structure has attracted more attentions due to its robust dielectric and luminescence properties. Complex cation distribution in spinel structure influences the optical and magnetic properties. Herein, we report white emission related to the defects and the magnetism assigned to Fe impurity in ZnAl2-xFexO4 (

0
≤
x
≤
0.6

) nanocrystals fabricated by using common sol-gel method at a relatively lower temperature (700 °C) than that reported earlier. ZnAl2-xFexO4 phosphors reveal single spinel phase without impure phase. Complex cation distribution is observed in all samples, for instance, Fe and Zn in antisites, cation vacancies, and with Fe content increasing, cation distribution reveals obvious change. The band gap energy of ZnAl2-xFexO4 phosphors is reduced from 3.84 eV to 3.33 eV when the content of Fe ions (x value) increases from 0 to 0.6. Two wide band emissions assigned to the various types of shallow and deep donor/acceptor defects are observed, monitoring with the excitation wavelength of 280 nm. The Commission International de I’Eclairage (CIE) colour coordinate (x, y) of the ZnAl2-xFexO4 phosphors is found to shift from (0.3218, 0.2957) to (0.3422, 0.3122) with Fe doping in spinel lattices owing to rearrangement of defects, indicating the potential application in white-light illumination. ZnAl2-xFexO4 reveals a room ferromagnetism resulting from Fe3 + ions in spinel lattices.
Characterization of carbonate apatite derived from chicken bone and its in-vitro evaluation using MC3T3-E1 cells
Authors: Xuan Thanh Tram Nguyen , Ishikawa Kunio , Minh Tran Hoang , Benson David , Tsuru Kanji
Published: January 2021

Chicken bone by-product has the potential to be utilized as a source of carbonate apatite (CO3Ap) for the preparation of bone grafts. In this study, the raw bones were cleaned with NaCl and then immersed in NaOH solution at 80 °C. After chemical treatment, the as-prepared powder was calcined in a range of 300 °C–900 °C. The results showed that calcination was useful for the complete elimination of organic residues; but, it led to increasing of crystal size, coarsening of particles, and the loss of the carbonate groups in the apatite structure. In vitro evaluation showed that CO3Ap prepared at the optimum temperature, 500 °C, exhibited a great biological response; such as good cell attachment, cell viability, and cell morphology. This research suggests a promising biomaterial for the fabrication of bone substitutes and could offer a solution for recycling and adding value to food waste.