bluuebunny/crossref_metadata_2025 huggingface dataset:
SPICE simulation of organic resistive memory with structure of ITO/polymethylmethacrylate/Al
Authors: Rong Jia-Ling  , Chen Yun-Han  , Zhou Jie  , Zhang Xue  , Wang Li  , Cao Jin  ,   Shanghai University School of Materials Science and Engineering, Shanghai 200072, China;,   Key Laborary of Advanced Display and System Applications, Shanghai University, Ministry of Education, Shanghai 200072, China
Published: December 2020

In this paper the resistive mechanism of the device with structure of ITO/PMMA/Al and the relevant SPICE simulation circuit are investigated. By optimizing the annealing temperature of PMMA, the devices can achieve continuous erasable-readable-writeable-readable operation. Based on the surface morphology researches of PMMA with different annealing temperatures, a physics model of nonlinear charge-drift mechanism in doping system is established to explain the resistance characteristics of the organic device. And the state equations are established to describe the interface movement of different doping regions in the model. Then, the SPICE simulation circuit is set up with feedback control integrator. Finally, substituting the measured parameters of device into the simulation circuit, we obtain the current-voltage simulation curve which is in good agreement with the actual results of the device. The results verify the resistance mechanism of nonlinear charge-drift in our device, and the applicability of the SPICE simulation of nonlinear charge-drift model based on inorganic memristors to the organic resistive memory.
Electric field induced polarization dynamics of graphene oxide
Authors: Gao Yan  , Chen Rui-Yun  , Wu Rui-Xiang  , Zhang Guo-Feng  , Xiao Lian-Tuan  , Jia Suo-Tang  ,   State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser Spectrum Shanxi University, Taiyuan 030006, China
Published: December 2020

We have changed the resonance energy of the graphene oxide molecular clusters by using the external electric field. From the graphene oxide resonance fluorescence we could study the polarization dynamics of graphene oxide under the electric field. It is found that the electric field makes the FWHM of fluorescence resonance peak tend to be saturated, and the temporal change of fluorescence resonance of the graphene oxide molecular clusters reflects the directional polarization and the deformation polarization generated in the graphene oxide due to the electric field.
Size effect of silk fibroin peptide chains in the growth process
Authors: Yang Meng-Shi  , Li Xin  , Ye Zhi-Peng  , Chen Liang  , Xu Can  , Chu Xiu-Xiang  ,   School of Engineering, Zhejiang A&F University, Zhejiang Province, Linan 311300, China;,   School of Science, Zhejiang A&F University, Zhejiang Province, Linan 311300, China;,   Key Lab for Magnetism and Magnetic Materials of Ministry of Education Lanzhou University, Lanzhou 730000, China
Published: December 2020

A theoretical study on 13 oligopeptides of glycine and alanine by density function theory (DFT) is given in this paper. Geometric structures, vibration frequency, average binding energies, dipole moment are studied, and IR spectra of the oligopeptides are examined. Results show that with increasing number of residues the average binding energies tend to a regular pattern, IR frequencies of typical functional groups start to shift, but stretching and bending vibrations of the groups show the opposite trend of red shift and blue shift. It is revealed that the physical and chemical properties of the silk fibroin peptide chain show size effect and anisotropic in the growth process. This phenomenon may come from the coupling effect of the similar groups, and the different effects of intramolecular hydrogen bond on the stretching and bending vibration.
Design of the ultra-thin perfect metamaterial absorber with high Q-factor
Authors: Li Si-Jia  , Cao Xiang-Yu  , Gao Jun  , Zheng Qiu-Rong  , Yang Qun  , Zhang Zhao  , Zhang Huan-Mei  ,   School of Information and Navigation, Air Force Engineering University, Xi’an 710077, China;,   School of Electronics and Information, North-Westen Polytechnical University, Xi’an 710072, China
Published: December 2020

A novel method to design an ultra-thin perfect metamaterial absorber (PMA) with high quality factor (Q-factor) at microwave frequencies is proposed to improve the absorption performance. The PMA achieves a high Q-factor by appropriately loading the metal cavity based on the substrate integrated waveguide (SIW) technology and the common PMA. An ultrathin absorber with a thickness of 0.0065λ and a full-width at half-maximum of 5.8% is designed. The Q-factor of absorptivity of the absorber is 33.9, which is enhanced by 20% compared with that of the conventional PMA. Meanwhile its Q-factors for radar cross section (RCS) reductions of 1.5 and 3 dBsm respectively increase 54% and 67% higher than those of the conventional PMA. The measured results show that the proposed SIW-PMA eliminates the frequency drift between the infinite periodic array and the finite periodic array, which occurs in the conventional design process. The simulated and measured results show that the proposed PMA has high Q-factor of absorptivity and excellent effect of RCS reduction. Its RCS reduction can reach a maximum value of 14.1 dBsm at the response frequency.
Experimental studies on pulsed neutron sensitivity of a fusion neutron spectrometer
Authors: Qi Jian-Min  , Zhou Lin  , Jiang Shi-Lun  , Zhang Jian-Hua  ,   Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900, China
Published: December 2020

A sensitivity optimized magnetic proton recoil (MPROS) spectrometer for measuring both steady and pulsed fusion neutron spectra in several complicated environments is developed. The proton energy-position projection relationship of the spectrometer is measured by utilizing an imaging plate. The energy response to neutron sensitivity of the MPROS spectrometer is studied through a single event count method on an accelerated steady DT neutron source and simulations by a three-dimensional charged particle transport code. The detection efficiency of the spectrometer to DT neutrons reaches a level of 2×10-5 cm2 through high efficiency parameter settings, therefore the experimental data of high statistic accuracy are obtained on a comparatively weak neutron source. Results from simulations and experiments, such as α particle calibrations, and DT neutron calibrations, achieve good consistency. Based on this conclusion, precise solution technique of measured spectra can be developed to increase the sensitivity and energy resolution of measurements of pulsed neutron spectroscopy.
Awareness and Perception of Undergraduate Students towards Risk Associated with Wireless Electromagnetic Field Radiation Exposure in Enugu, South-East Nigeria: A Cross-sectional Study
Authors: Mgbe Emeka Kevin , Mgbe Chinenye Glory , Ajare Chuks Enyereibe , Nnamani Amaka Obiageli
Published: December 2020

Introduction: Use of telecommunication equipment (cell phone or mobile phone, tablets, walkie-talkie, ipads, ipods, android) has been on the increase globally. There is an estimate of over 145 million active subscribers on record in Nigeria. Hence, there is need for correct information about the associated risk of Electromagnetic Field (EMF) exposure of equipment so as to curb its debilitating effects. Aim: To evaluate the level of awareness and perceived health risks of EMFs exposure (Radiation) among undergraduate students’ of various discipline. Materials and Methods: The Health Belief Model (HBM) was used with descriptive cross-sectional research design from March 2017 to November 2018 to evaluate awareness and perception of EMF radiation exposure. Structured questionnaire, focus group discussion and in-depth interviews with a predominantly 1-5 scale grading was applied for data collection. Data analysis was conducted using Statistical Package for Social Science (SPSS) version 14 with correlation coefficient (r) and Chi-square test (χ2) of p-value <0.05 as significant. Results: A total of 576 undergraduate students from six tertiary institutions in Enugu State, Eastern Nigeria were recruited for the study. A total of 43% were males while 57% were females. Even though majority (93.9%) of the respondents rightly defined the meaning of EMF as a wave that transmits energy through space or material medium, only 34.6% had significant awareness of the radiation effect of this equipment. About 82% of respondents kept their telecommunication equipment close to their body thereby increasing exposure to EMF. The correlation coefficient (r) is 0.806 and the p-value <0.05 shows that there is a high positive relationship between risk reduction strategies like use of hand-free/ear piece etc., and level of awareness among students. There was significant positive correlation between awareness of EMF radiation and faculty of studies as well between perceived EMF risk and year of study (Each p-value <0.05). Conclusion: Increase in the level of health education is a key to reduction of risk of EMF exposure (Radiation) among undergraduate telecommunication equipment users and this invariably applies to the entire general population.
Synthesis and Characterization of Bi13B0.48V0.49-xPxO21.45 and Efficient Catalyst for the Synthesis of 2,3-dihydroquinazolin-4(1H)-ones Derivatives Synthesis
Authors: Barebita Hanane , Merroun Youssef , Ferraa Soumya , Nimour Abderrazak , Souizi Abdelaziz , Guedira Taoufiq
Published: December 2020

A new compound has been found in the system Bi13B0.48V0.49-x PxO21.45 (with 0≤x≤0.34), were prepared by the direct solid-state reaction of Bi2O3, (NH4)2HPO4, V2O5, and B2O3. This material melts congruently and it crystallize with the sillenite structure (space group I23) and form a solid solution with the cubic lattice parameter increasing from with a = 10.1568 Å to 10.1436 Å with increasing of P2O5 molar. Consequently, the new composites belong to g-variety of solid state. The samples have been characterized by Fourier transform infrared spectroscopy (FT-IR), diffraction XRD and scanning electron microscopy (SEM) coupled to the EDX. On the other hand, the valorization of the prepared composites was performed by using them as heterogeneous catalyst in the 2,3-dihydroquinazolin-4(1H)-ones derivatives synthesis. The catalyst is stable (as a bench top catalyst) and reusable. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).
Multi‐physics modeling of doxorubicine binding to ion‐exchange resin in blood filtration devices
Authors: Maani Nazanin , Balsara Nitash , Hetts Steven W. , Rayz Vitaliy L.
Published: December 2020

A group of drugs used in intra‐arterial chemotherapy (IAC) have intrinsic ionic properties, which can be used for filtering excessive drugs from blood in order to reduce systemic toxicity. The ion‐exchange mechanism is utilized in an endovascular Chemofilter device which can be deployed during the IAC for capturing ionic drugs after they have had their effect on the tumor. In this study, the concentrated solution theory is used to account for the effect of electrochemical forces on the drug transport and adsorption by introducing an effective diffusion coefficient in the advection–diffusion–reaction equation. Consequently, a multi‐physics model coupling hemodynamic and electrochemical forces is developed and applied to simulations of the transport and binding of doxorubicine in the Chemofilter device. A comparison of drug adsorption predicted by the computations to that measured in animal studies demonstrated the benefits of using the concentrated solution theory over the Nernst–Plank relations for modeling drug binding.
Additive manufacturing of PA12 carbon nanotube composites with a novel laser polymer deposition process
Authors: Wencke Yannick L. , Kutlu Yunus , Seefeldt Malte , Esen Cemal , Ostendorf Andreas , Luinstra Gerrit A.
Published: December 2020

The facile manufacture of PA12 MWCNT/silica (50/50 by weight) nanocomposite powders through a high energy mixing process is presented, which are useful to generate 3D objects by a novel Laser Polymer Deposition (LPD) process. The mixing as well as the LPD process led to no discernible changes in the material properties (DSC, SEM, LD) of the core‐shell nanocomposites, enabling the recycling of unconverted powder. The built parts yield ultimate tensile stresses and Young's modulus at 10%–20% of the bulk material. Partially unmolten particles and voids were identified as the main mechanical failure mechanism in the built parts. The mechanical properties are better with low additive content (Young's modulus: 89.8 ± 5.4 MPa; UTS: 12.9 ± 5.3 MPa with 0.25 wt% additives). Electronic conductivity up to the region of moderate conductivity could be achieved by multiwalled carbon nanotube (MWCNT) network formation (8 × 10−4 S cm−1 at 1.25 wt% of additives). A variant of the processing strategy revealed that a higher mechanical strength can be achieved by a laser induced remelting of the traces following their initial construction.
Physiologically based pharmacokinetic model of renally cleared antibacterial drugs in Chinese renal impairment patients
Authors: Cui Cheng , Li Xiaobei , Liang Hao , Hou Zhe , Tu Siqi , Dong Zhongqi , Yao Xueting , Zhang Miao , Zhang Xuan , Li Haiyan , Zuo Xiaocong , Liu Dongyang
Published: December 2020

To preliminarily develop physiologically based population models for Chinese renal impairment patients and to evaluate the prediction performance of new population models by renally cleared antibacterial drugs. First, demographic data and physiological parameters of Chinese renal impairment patients were collected, and then the coefficients of the relative demographic and physiological equation were recalibrated to construct the new population models. Second, drug‐independent parameters of ceftazidime, cefodizime, vancomycin, and cefuroxime were collected and verified by Chinese healthy volunteers, Caucasian healthy volunteers, and Caucasian renal impairment population models built in Simcyp. Finally, the newly developed population models were applied to predict the plasma concentration of four antibacterial drugs in Chinese renal impairment patients. The new physiologically based pharmacokinetic (PBPK) population models can predict the main pharmacokinetic parameters, including area under the plasma concentration–time curve extrapolated to infinity (AUCinf), renal clearance (CLr), and peak concentration (Cmax), of ceftazidime, cefodizime, vancomycin, and cefuroxime following intravenous administrations with less than twofold error in mild, moderate, and severe Chinese renal impairment patients. The accuracy and precision of the predictions were improved compared with the Chinese healthy volunteers and Caucasian renal impairment population models. The PBPK population models were preliminarily developed and the first‐step validation results of four antibacterial drugs following intravenous administration showed acceptable accuracy and precision. The population models still need more systematic validation by using more drugs and scenarios in future studies to support their applications on dosage recommendation for Chinese renal impairment patients.
Preparative isolation of the major metabolite NK‐1375 of diamide insecticide cyclaniliprole and its application to pertinent residue analysis in plant‐origin foods using UHPLC–MS/MS
Authors: Lu Zhou , Pan Hongyu
Published: December 2020

NK‐1375 is a major metabolite of the diamide insecticide cyclaniliprole (CYCP) with toxicological significance. It is formed in various transformation pathways of CYCP, including photolysis and plant metabolism. In the present study, NK‐1375 was produced employing the liquid‐phase photolysis of CYCP followed by isolation using preparative liquid chromatography. The structure of the isolated substance was confirmed using MS and 1H NMR spectroscopy, and its purity was measured to be 95.9% using HPLC. As its application, a residue analysis method was first developed for the simultaneous determination of CYCP and NK‐1375 in six representative plant‐origin foods using fast multi‐plug filtration cleanup and UHPLC–MS/MS. Excellent linearity (r > 0.999) was obtained over the calibration range from 0.001 to 0.1 μg mL−1. The recoveries (intra‐day and inter‐day) of CYCP and NK‐1375 from different matrices ranged from 74 to 112%, with corresponding relative standard deviations less than 13%. The limits of quantitation of these two compounds were defined at 0.01 mg kg−1. This study can be useful for the subsequent analytical or toxicological research on this important pesticide metabolite.
Survival benefit from immunocheckpoint inhibitors in stage IV non‐small cell lung cancer patients with brain metastases: A National Cancer Database propensity‐matched analysis
Authors: Takamori Shinkichi , Komiya Takefumi , Powell Emily
Published: December 2020

Immunocheckpoint inhibitors (ICIs) have become a standard pharmacological therapy in non‐small cell lung cancer (NSCLC). Because brain metastases (BMs) have historically been listed as exclusion criteria in previous clinical trials involving ICIs in advanced NSCLC, the survival benefit from ICI in NSCLC patients with BMs remains unclear. The National Cancer Database was queried for stage IV NSCLC patients with or without BMs between 2014 and 2015. Overall survival (OS) of stage IV NSCLC patients who received immunotherapy and that of stage IV NSCLC patients who did not receive immunotherapy were compared according to the presence or absence of BMs. Multivariable logistic analyses identified the clinical characteristics predictive of overall survival. A propensity score analysis was conducted with the aim of adjusting the potential biases arising from the clinical characteristics. This study included 42,512 patients with stage IV NSCLC; 11,810 patients with BMs and 30,702 patients without BMs. In univariate analysis, stage IV NSCLC patients with BMs treated with immunotherapy had a significantly longer OS than those without immunotherapy after propensity score matching (median OS: 12.8 vs 10.1 months, hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.72–0.89, p < 0.0001). Multivariable Cox modeling after propensity score matching confirmed the survival benefit from ICI for stage IV NSCLC patients with BMs (HR: 0.75, 95% CI: 0.67–0.83, p < 0.0001). The HR in NSCLC patients without BMs treated with ICI compared with those without ICI was 0.77 (95% CI: 0.73–0.82, p < 0.0001). Survival in stage IV NSCLC patients with BMs was significantly improved by ICI treatment at levels comparable to those without BMs using a retrospective database. ICI may be one of the promising treatment options for stage IV NSCLC patients with BMs. These findings should be validated in future prospective studies.
Effect of gibberellic acid and nitrogen application on biomass and nutritive value of annual ryegrass
Authors: Lemus Rocky , White Joshua A. , Morrison Jesse I.
Published: December 2020

Enhancing the growth of annual ryegrass (Lolium multiflorum Lam.) would be beneficial to livestock producers to decrease supplementation. The objective of the study was to examine the effects of nitrogen (N) and gibberellic acid (GA) in biomass production and nutritive. We evaluated the application of N (0, 20, and 40 lb N acre–1) and RyzUp Smartgrass (RYZ) [gibberellic acid (gibberellin A3)] at a rate of 0.4 oz acre–1 across two growing seasons (2011–2012 and 2012–2013). The experimental design was a split‐plot replicated four times. The main plots consisted of four treatment application dates (mid‐December, early and late January, and mid‐February) and the subplots consisted of four treatments (RYZ, 40 lb N acre‐1 [40N], 20 lb N acre‐1 [20N] plus RYZ, and 40N plus RYZ) and untreated control (UC). Seasonal dry matter (DM) yield was not different between UC and RYZ treatments, while N treatments had significantly greater biomass production but were not different from each other. RYZ had a 5% yield increase while 40N+RYZ had a 26% yield increase compared with UC. Treatment had a significant effect on crude protein (CP) (P < .01), neutral detergent fiber (NDF) (P = .02), and water‐soluble carbohydrate (WSC) (P < .01). No differences in WSC were detected between UC and RYZ treatments, while the treatments containing N had a slight decrease in concentration. Data suggests that temperatures in the southern United States during annual ryegrass production might be too mild to observe a GA response at the applied rates.
Pulse‐assisted fluidization of nanoparticles: Case of lithium iron phosphate material
Authors: Aghaee Sarbarze Samira , Latifi Mohammad , Rasouli Majid , Rousselot Steeve , Dollé Mickaël , Chaouki Jamal
Published: December 2020

Pulse‐assisted fluidization was developed for the fluidization of nanoparticles at high‐temperature processes (eg, above 600°C, depending on the material of interest). The technique was employed for carbon coating of lithium iron phosphate (LFP) nanoparticles with a gas‐phase carbon precursor (ie, propylene) through chemical vapour deposition (PAFB‐CVD). LFP has been extensively investigated as an environmentally friendly and cost‐effective cathode material of rechargeable lithium‐ion batteries. LFP nanoparticles of this research were, in fact, cohesive secondary particles of Geldart's group C. The CVD tests were carried out at temperatures between 600°C‐750°C. Uniform layers of carbon were deposited on the surface of LFP nanoparticles with a thickness less than 10 nm while particles were not sintered under high temperature operations. Also, the generated C‐LFP material held a superior electrical conductivity of 1010 times more than the conductivity of uncoated raw LFP; it also featured a significant enhancement of discharge capacity despite the considerable delay between the production of raw LFP nanoparticles and the CVD process.
Recent Advance in Carbon Dots: From Properties to Applications
Authors: Wu Hao , Xu Huimin , Shi Yuxin , Yuan Ting , Meng Ting , Zhang Yang , Xie Wenjing , Li Xiaohong , Li Yunchao , Fan Louzhen
Published: December 2020

As a new type of nanomaterial, carbon dots (CDs) have been recognized as a versatile nanoplatform with enormous potential for biomedical and optoelectronic applications because of low cytotoxicity, photostability, biocompatibility and versatility in addition to their tunable photoluminescence. In this review, we aim at updating the latest research on preparation, optoelectronic and chemical properties of CDs as well as their biomedical and optoelectronic applications. We highlight the applications of CDs for stem cell imaging, cell nucleus imaging, two‐photon fluorescence imaging, tumor diagnosis and therapy and their optoelectronic applications including light‐emitting diodes (LEDs), solar cells and electrocatalysis. Furthermore, we also discuss current challenges and breakthroughs on machine‐learning‐driven synthesis of CDs as well as nucleic acid detection with an eye towards the future. Finally, we hope that this review will give further impulses to target‐oriented research on CDs for biomedical and optoelectronic applications.
Forebrain projection neurons target functionally diverse respiratory control areas in the midbrain, pons, and medulla oblongata
Authors: Trevizan‐Baú Pedro , Dhingra Rishi R. , Furuya Werner I. , Stanić Davor , Mazzone Stuart B. , Dutschmann Mathias
Published: December 2020

Eupnea is generated by neural circuits located in the ponto‐medullary brainstem, but can be modulated by higher brain inputs which contribute to volitional control of breathing and the expression of orofacial behaviors, such as vocalization, sniffing, coughing, and swallowing. Surprisingly, the anatomical organization of descending inputs that connect the forebrain with the brainstem respiratory network remains poorly defined. We hypothesized that descending forebrain projections target multiple distributed respiratory control nuclei across the neuroaxis. To test our hypothesis, we made discrete unilateral microinjections of the retrograde tracer cholera toxin subunit B in the midbrain periaqueductal gray (PAG), the pontine Kölliker‐Fuse nucleus (KFn), the medullary Bötzinger complex (BötC), pre‐BötC, or caudal midline raphé nuclei. We quantified the regional distribution of retrogradely labeled neurons in the forebrain 12–14 days postinjection. Overall, our data reveal that descending inputs from cortical areas predominantly target the PAG and KFn. Differential forebrain regions innervating the PAG (prefrontal, cingulate cortices, and lateral septum) and KFn (rhinal, piriform, and somatosensory cortices) imply that volitional motor commands for vocalization are specifically relayed via the PAG, while the KFn may receive commands to coordinate breathing with other orofacial behaviors (e.g., sniffing, swallowing). Additionally, we observed that the limbic or autonomic (interoceptive) systems are connected to broadly distributed downstream bulbar respiratory networks. Collectively, these data provide a neural substrate to explain how volitional, state‐dependent, and emotional modulation of breathing is regulated by the forebrain.
Synergistic effects of long‐term herbivory and previous fire on fine‐scale heterogeneity of prescribed grassland burns
Authors: Werner Chhaya M. , Kimuyu Duncan , Veblen Kari E. , Sensenig Ryan L. , LaMalfa Eric , Young Truman P.
Published: December 2020

Grassland and savanna ecosystems, important for both livelihoods and biodiversity conservation, are strongly affected by ecosystem drivers such as herbivory, fire, and drought. Interactions among fire, herbivores and vegetation produce complex feedbacks in these ecosystems, but these have rarely been studied in the context of fuel continuity and resultant fire heterogeneity. We carried out 36 controlled burns within replicated experimental plots that had allowed differential access by wild and domestic large herbivores since 1995 in a savanna ecosystem in Kenya. Half of these were reburns of plots burned 5 yr previously. We show here that the fine‐scale spatial heterogeneity of fire was greater in plots (1) previously burned, (2) accessible to large herbivores, and especially (3) these two in combination. An additional embedded experiment demonstrated that even small experimental burn‐free patches can have strong positive effects on tree saplings, which experienced less damage during controlled burns and quicker postfire recovery. This work highlights the importance of simultaneously examining the interactions between fire and herbivory on fuel heterogeneity, which can have important impacts on the growth of woody saplings in savanna grasslands.
Polarity effect of breakdown characteristics across micrometer‐scale surface gap
Authors: Iwabuchi Hiroyuki , Oyama Tsutomu , Kumada Akiko , Hidaka Kunihiko
Published: December 2020

With a miniaturization of electrical devices, the gap between electrode becomes lower and lower. In order to optimize the insulation design, the understanding of breakdown phenomenon across micrometer‐scale gap is essential. In this study, breakdown characteristics across micrometer‐scale gap was investigated based on experiment and numerical simulation. The result shows that the breakdown voltage under positive voltage application is 1.5 times higher than the one under the negative voltage application. The polarity effect can be explained by the source of initial electrons. Under negative voltage application, the initial electrons are emitted from the cathode surface based on Fowler‐Nordheim equation. On the other hand, under positive voltage application, the insulator plays an important role on breakdown voltage.
Assessment of 1/f noise associated with nanopores fabricated through chemically tuned controlled dielectric breakdown
Authors: Saharia Jugal , Bandara Y. M. Nuwan D. Y. , Karawdeniya Buddini I. , Alexandrakis George , Kim Min Jun
Published: December 2020

Recently, we developed a fabrication method—chemically‐tuned controlled dielectric breakdown (CT‐CDB)—that produces nanopores (through thin silicon nitride membranes) surpassing legacy drawbacks associated with solid‐state nanopores (SSNs). However, the noise characteristics of CT‐CDB nanopores are largely unexplored. In this work, we investigated the 1/f noise of CT‐CDB nanopores of varying solution pH, electrolyte type, electrolyte concentration, applied voltage, and pore diameter. Our findings indicate that the bulk Hooge parameter (αb) is about an order of magnitude greater than SSNs fabricated by transmission electron microscopy (TEM) while the surface Hooge parameter (αs) is ∼3 order magnitude greater. Theαs of CT‐CDB nanopores was ∼5 orders of magnitude greater than theirαb, which suggests that the surface contribution plays a dominant role in 1/f noise. Experiments with DNA exhibited increasing capture rates with pH up to pH ∼8 followed by a drop at pH ∼9 perhaps due to the onset of electroosmotic force acting against the electrophoretic force. The1/f noise was also measured for several electrolytes and LiCl was found to outperform NaCl, KCl, RbCl, and CsCl. The 1/f noise was found to increase with the increasing electrolyte concentration and pore diameter. Taken together, the findings of this work suggest the pH approximate 7–8 range to be optimal for DNA sensing with CT‐CDB nanopores.
TF33 Turbofan engine in every respect: Performance, environmental, and sustainability assessment
Authors: Balli Ozgur , Ekici Selcuk , Karakoc T. Hikmet
Published: December 2020

The performance parameters, environmental sensitivity, and sustainability of a turbofan engine used extensively in military aviation are examined to the last detail. Assessment parameters named as energy efficiency, specific fuel consumption (SFC) and thrust, fuel heating value ratio (FHVR), thermal limit ratio (TLR), enthalpy ratio (ER), engine thrust ratio (ETR), fuel cost rate (FCR), specific fuel cost rate (SFCR), exergy efficiency, exergy destruction ratio, exergy loss ratio (ExLR), waste exergy ratio (WExR), exergetic improvement potential (ExIP), relative exergetic improvement potential (RExIP), productivity lack ratio (PLR), fuel exergy waste ratio (FExWR), environmental effect factor (EEF), ecological effect factor (EcoEF), sustainable efficiency factor (SEF), and exergetic sustainability index (ESI) were used to analyze thermodynamically the engine. The most sustainable and environmentally friendly components are researched and the results are presented to the literature. Between the components, the combustion chamber (CC) has the highest EEF with 0.8627 and the highest EcoEF value with 1.8627. Comparing the engine components, the low‐pressure turbine (LPT) has the best SEF value with 67.83 and the best ESI value with 66.83. Conversely, the CC has the worst SEF value with 2.16 and the best ESI value with 1.16. Ultimately, environmental and sustainability results from the analysis are expected to help understand the link between turbofan engine selection for both commercial and military aircraft and green flight paths, and therefore, make the choice of turbofan engines environmentally benign and greener.
The emergence and intensification of early hunter‐gatherer niche construction
Authors: Thompson Jessica C. , Wright David K. , Ivory Sarah J.
Published: December 2020

Hunter‐gatherers, especially Pleistocene examples, are not well‐represented in archeological studies of niche construction. However, as the role of humans in shaping environments over long time scales becomes increasingly apparent, it is critical to develop archeological proxies and testable hypotheses about early hunter‐gatherer impacts. Modern foragers engage in niche constructive behaviors aimed at maintaining or increasing the productivity of their environments, and these may have had significant ecological consequences over later human evolution. In some cases, they may also represent behaviors unique to modern Homo sapiens. Archeological and paleoenvironmental data show that African hunter‐gatherers were niche constructors in diverse environments, which have legacies in how ecosystems function today. These can be conceptualized as behaviorally mediated trophic cascades, and tested using archeological and paleoenvironmental proxies. Thus, large‐scale niche construction behavior is possible to identify at deeper time scales, and may be key to understanding the emergence of modern humans.
Complex mediating effects of rumination facets between personality traits and depressive symptoms
Authors: Lyon Kieran A. , Elliott Rebecca , Brown Laura J. E. , Eszlari Nora , Juhasz Gabriella
Published: December 2020

This study investigates whether facets of rumination statistically mediate the relationships between Big Five personality traits and depressive symptoms. Self‐reported personality traits and rumination were investigated as predictors of depressive symptoms in a cross‐sectional sample of 3043 participants aged 18–60 years (68.8% female). Multiple regression analysis investigated which personality traits and rumination facets best explained variance in depressive symptoms. Structural equation modelling was used to determine whether facets of rumination mediated the relationships between personality traits and depressive symptoms. Multiple regression analysis found that variance in depressive symptoms was best explained by the personality traits neuroticism, extroversion, conscientiousness; and both facets of rumination, brooding and reflection. Structural equation modelling added that the effects of neuroticism, extroversion, conscientiousness and openness on depressive symptoms were statistically mediated by brooding; the effects of neuroticism, extroversion and openness to depressive symptoms were statistically mediated by reflection. Rumination facets statistically mediated the effects of various personality traits on depressive symptoms. These results provide insights into which individuals may be best suited to treatments for depression targeting rumination.
Interleukin‐4 repairs wear particle induced osteolysis by modulating macrophage polarization and bone turnover
Authors: Pajarinen Jukka , Lin Tzuhua , Nabeshima Akira , Sato Taishi , Gibon Emmanuel , Jämsen Eemeli , Khan Tahsin N. , Yao Zhenyu , Goodman Stuart B.
Published: December 2020

Periprosthetic osteolysis remains as a major complication of total joint replacement surgery. Modulation of macrophage polarization with interleukin‐4 (IL‐4) has emerged as an effective means to limit wear particle‐induced osteolysis. The aim of this study was to evaluate the efficacy of local IL‐4 delivery in treating preexisting particle‐induced osteolysis. To this end, recently established 8 week modification of murine continuous femoral intramedullary particle infusion model was utilized. Subcutaneous infusion pumps were used to deliver polyethylene (PE) particles into mouse distal femur for 4 weeks to induce osteolysis. IL‐4 was then added to the particle infusion for another 4 weeks. This delayed IL‐4 treatment (IL‐4 Del) was compared to IL‐4 delivered continuously (IL‐4 Cont) with PE particles from the beginning and to the infusion of particles alone for 8 weeks. Both IL‐4 treatments were highly effective in preventing and repairing preexisting particle‐induced bone loss as assessed by μCT. Immunofluorescence indicated a significant reduction in the number of F4/80 + iNOS + M1 macrophages and increase in the number of F4/80 + CD206 + M2 macrophages with both IL‐4 treatments. Reduction in the number of tartrate resistant acid phosphatase + osteoclasts and increase in the amount of alkaline phosphatase (ALP) + osteoblasts was also observed with both IL‐4 treatments likely explaining the regeneration of bone in these samples. Interesting, slightly more bone formation and ALP + osteoblasts were seen in the IL‐4 Del group than in the IL‐4 Cont group although these differences were not statistically significant. The study is a proof of principle that osteolytic lesions can be repaired via modulation of macrophage polarization.
Therapeutic plasma exchange with albumin as a valuable method of preparing thyrotoxic patients for a life‐saving thyroidectomy
Authors: Tańska Kamila , Leszczyńska Dorota , Glinicki Piotr , Kapuścińska Renata , Szczepkowski Marek , Dedecjus Marek , Stachlewska‐Nasfeter Elżbieta , Brym Izabela , Żelek Tomasz , Daniewska Dorota , Gietka‐Czernel Małgorzata
Published: December 2020

Hyperthyroidism affects approximately 1.2% of the population and its routine treatment includes antithyroid drugs (ATDs), radioiodine and surgery. Management of patients with resistance or contraindications to ATDs who require thyroidectomy may be challenging. We present the experience of our department in preparing thyrotoxic patients for life‐saving thyroidectomy by using therapeutic plasma exchange (TPE) with albumin: one patient with Graves' disease and previous history of agranulocytosis and cholestatic jaundice after ATDs and two patients with amiodarone‐induced thyrotoxicosis. Five to six TPEs were applied to each patient resulting in a decrease of fT3 by 57% to 83%, fT4 by 21% to 60% and decrease/normalization of total thyroid hormones. All patients underwent surgery successfully. In case of drug‐resistant thyrotoxicosis or contraindications to ATDs, TPE can be a valuable tool in preparing patients for surgery. Albumin used as a replacement fluid appears to be effective in ameliorating clinical and laboratory symptoms of thyrotoxicosis.
Implementing a human factors approach to RCA2: Tools, processes and strategies
Authors: Wiegmann Douglas A. , Wood Laura J. , Solomon Demetrius B. , Shappell Scott A.
Published: December 2020

Root Cause Analysis and Action (RCA2) guidelines offer fundamental improvements to traditional RCA. Yet, these guidelines lack robust methods to support a human factors analysis of patient harm events and development of systems‐level interventions. We recently integrated a complement of human factors tools into the RCA2process to address this gap. These tools include the Human Factors Analysis and Classification System (HFACS), the Human Factors Intervention Matrix (HFIX), and a multiple‐criterion decision tool called FACES, for selecting effective HFIX solutions. We describe each of these tools and illustrate how they can be integrated into RCA2to create a robust human factors RCA process called HFACS‐RCA2. We also present qualitative results from an 18‐month implementation study within a large academic health center. Results demonstrate how HFACS‐RCA2can foster a more comprehensive, human factors analysis of serious patient harm events and the identification of broader system interventions. Following HFACS‐RCA2implementation, RCA team members (risk managers and quality improvement advisors) also experienced greater satisfaction in their work, leadership gained more trust in RCA findings and recommendations, and the transparency of the RCA process increased. Effective strategies for overcoming implementation barriers, including changes in roles, responsibilities and workload will also be presented.
Editorial for “Can arterial spin labeling perfusion imaging be used to differentiate nasopharyngeal carcinoma from nasopharyngeal lymphoma?”
Authors: Gökçe Erkan
Published: December 2020

Level of Evidence

5

Technical Efficacy Stage

2
Biogeochemical characteristics and hydroperiod affect carbon dioxide flux rates from exposed high‐elevation pond sediments
Authors: DelVecchia Amanda Gay , Gougherty Steven , Taylor Brad W. , Wissinger Scott A.
Published: December 2020

While inundated, small ponds (< 1000 m2 area) account for disproportionately large contributions of CO2 efflux to the global carbon budget and also store carbon in anoxic sediments. However, pond hydrology is shifting toward increasingly dry conditions in alpine and temperate zones, which might lead to increased exposure of shallow pond sediments. We analyzed sediment CO2 efflux rates in dried sediments of multiple ponds of varying hydrology and sediment characteristics at montane and subalpine elevations near the Rocky Mountain Biological Laboratory in Colorado. Average CO2 efflux rates from exposed sediments, 331.5 ± 11.5 mmol m−2 d−1 at the montane sites and 142.8 ± 45.1 mmol m−2 d−1 at the subalpine sites, were 10 times higher than average CO2 efflux rates from pond water. Principal components analysis to reduce dimensionality of sediment characteristics revealed that random inter‐pond differences rather than exposure timing or hydroperiod drove variation among sediments. In linear mixed effects models of CO2 flux rates, significant predictors included sediment moisture and temperature, pH, total organic carbon, and organic matter content at all pond hydroperiod classifications and sites. However, the sediment characteristics explaining the most variance differed among sites and hydroperiods and included nitrate concentrations, pH, bulk density, and temperature. We conclude that pond sediments are heterogeneous both within and among ponds in close proximity, and drivers of relatively high CO2 efflux rates differ among pond hydroperiods and elevations. This work emphasizes that local differences can impact predictions of CO2 flux from lentic sediments which are becoming increasingly exposed.
Existence and controllability of nonlocal mixedVolterra‐Fredholmtype fractional delay integro‐differential equations of order 1 < r < 2
Authors: Kavitha Williams W. , Vijayakumar V. , Udhayakumar R. , Panda Sumati Kumari , Nisar Kottakkaran Sooppy
Published: December 2020

In our article, we are primarily concentrating on existence and controllability of nonlocal mixed Volterra‐Fredholm type fractional delay integro‐differential equations of order 1 < r < 2. By applying the results and facts belongs to the cosine function of operators, fractional calculus, the measure of noncompactness and fixed point approach, the main results are established. Initially, we focus the existence of mild solution, and later we establish the controllability of the considered fractional system. Finally, we present an example to demonstrate the theory.
Simultaneous detection of fetal aneuploidy, de novoFGFR3 mutations and paternally derived β‐thalassemia by a novel method of noninvasive prenatal testing
Authors: Yang Lin , Wu Yujing , Hu Zhiyang , Zhang Haiping , Pu Dandan , Yan Huijuan , Zhang Sijia , Jiang Hui , Liu Qiang , Yuan Yuying , Zhang Yanyan , Chen Fang , Lu Yanping , Pan Silin , Lin Linhua , Gao Ya
Published: December 2020

Objective

The aim is to develop a novel noninvasive prenatal testing (NIPT) method that simultaneously performs fetal aneuploidy screening and the detection of de novo and paternally derived mutations.

Methods

A total of 68 pregnancies, including 26 normal pregnancies, 7 cases with fetal aneuploidies, 7 cases with fetal achondroplasia or thanatophoric dysplasia, 18 cases with fetal skeletal abnormalities, and 10 cases with β‐thalassemia high risk were recruited. Plasma cell‐free DNA was amplified by Targeted And Genome‐wide simultaneous sequencing (TAGs‐seq) to generate around 99% of total reads covering the whole‐genome region and around 1%  covering the target genes. The reads on the whole‐genome region were analyzed for fetal aneuploidy using a binary hypothesis T‐score and the reads on target genes were analyzed for point mutations by calculating the minor allelic frequency of loci on FGFR3 and HBB. TAGs‐seq results were compared with conventional NIPT and diagnostic results.

Results

In each sample, TAGs‐seq generated 44.7–54 million sequencing reads covering the whole‐genome region of 0.1–3× and the target genes of >1000×depth. All cases of fetal aneuploidy and de novo mutations of achondroplasia/thanatophoric dysplasia were identified with high sensitivities and specificities except for one false‐negative paternal mutation of β‐thalassemia.

Conclusions

TAGs‐seq is a novel NIPT method that combines the fetal aneuploidy screening and the detection of de novo FGFR3 mutations and paternal HBB mutations.
Interlaminar strength in large‐scale additive manufacturing of slow crystallizing polyaryletherketone carbon composites
Authors: Consul Patrick , Chaplin Adam , Tagscherer Nevine , Zaremba Swen , Drechsler Klaus
Published: December 2020

Fusion bonding theory is applied to the additive manufacturing process to predict the strength developed across the interface between the deposited layers in material extrusion based large‐scale additive manufacturing. Relaxation times were determined through rheology investigations of the neat polymers and were extrapolated across the entire process temperature range to estimate the required welding times for optimal bond formation. For the calculation of bond formation during cooling from the melt, the semicrystalline polyaryletherketone is considered amorphous until the onset of crystallization which is determined by recreating the process thermal history in DSC measurements. A significant improvement in bond development during additive manufacturing is achieved through the use of specifically designed polymers with slower crystallization kinetics. Both in small‐scale additive manufacturing, achieving full bonding, and in large‐scale additive manufacturing, they achieve significantly higher interlaminar strength than the reference material, validated by three‐point bending. A very good match between the estimated degree of bonding and the tested strength of upright printed specimens in three‐point bending was found. While the fusion bonding model calculates a degree of bonding of 42.07%, mechanical testing showed 42.54% of the bulk flexural strength. The study outlines a procedure to evaluate materials for additive manufacturing by material extrusion based on small material samples to shorten and improve the process development. © 2020 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry
The Impact of an Ultrasound Curriculum on the Accuracy of Resident Joint Line Palpation
Authors: Bowers Robert , Neuberger David , Williams Christopher , Kneer Lee , Sussman Walter
Published: December 2020

Background

Ultrasound education has been used as a tool to help improve physical examination skills. However, its utility in increasing accuracy of joint line palpation has yet to be investigated.

Objective

To evaluate the accuracy of resident palpation and identification of the lateral knee joint line before and after introducing a musculoskeletal ultrasound (MSUS) curriculum.

Design

Cohort study.

Setting

A physical medicine and rehabilitation (PM&R) residency program at an academic institution.

Participants

Seventeen PM&R residents.

Interventions

Residents underwent a knee‐focused MSUS workshop.

Main Outcome Measures

Distance from needle placement to joint line confirmed with ultrasound.

Results

All residents demonstrated improved accuracy in lateral knee joint line palpation after completing a knee‐focused MSUS workshop, with statistically significant (P < .05) improvement in postgraduate year (PGY) 2 (P = .02), PGY‐3 (P = .04), and across all residents (P = .001).

Conclusions

MSUS education significantly improved lateral knee joint line palpation accuracy in resident physicians.