bluuebunny/crossref_metadata_2025 huggingface dataset:
Retraction: Mesoporous amorphous FeOF nanococoons for high-rate and long-life rechargeable sodium-ion batteries
Authors: Tong Dong Ge
Published: August 2019

Retraction of ‘Mesoporous amorphous FeOF nanococoons for high-rate and long-life rechargeable sodium-ion batteries’ by Shi Yan Fu et al., J. Mater. Chem. A, 2015, 3, 16716–16727.
Retraction: One-pot synthesis of O-doped BN nanosheets as a capacitive deionization electrode for efficient removal of heavy metal ions from water
Authors: Tong Dong Ge
Published: August 2019

Retraction of ‘One-pot synthesis of O-doped BN nanosheets as a capacitive deionization electrode for efficient removal of heavy metal ions from water’ by Ming Ming Chen et al., J. Mater. Chem. A, 2017, 5, 17029–17039.
Retraction: Novel mesoporous amorphous B–N–O–H nanofoam as an electrode for capacitive dye removal from water
Authors: Tong Dong Ge
Published: August 2019

Retraction of ‘Novel mesoporous amorphous B–N–O–H nanofoam as an electrode for capacitive dye removal from water’ by Ming Ming Chen et al., J. Mater. Chem. A, 2017, 5, 21400–21413.
Auditory and Cognitive Attributes of Hearing Aid Acclimatization in Individuals With Sensorineural Hearing Loss
Authors: Megha  , Maruthy Sandeep
Published: August 2019

Purpose

The study aimed to investigate the underlying mechanisms of perceived benefit of hearing aid acclimatization. Specifically, measures in the auditory and cognitive domain were tapped to investigate its relationship with the perceived benefit.

Method

Twenty-six individuals with sensorineural hearing loss served as participants for the study. The perceived benefit of hearing aid use was assessed using the Speech, Spatial and Qualities of Hearing Scale (SSQ;Gatehouse & Noble, 2004). Signal-to-noise ratio-50 (SNR-50) and acceptable noise levels were the measures in auditory domain, whereas working memory and listening effort (LE) were the measures in cognitive domain. All the measures were tracked over a span of 2 months of hearing aid use to determine the benefits of hearing aid acclimatization.

Results

The SSQ showed improvements from baseline to 2nd month of hearing aid use. The mean improvement in the SNR-50 scores was 3.19 dB from the baseline. Acceptable noise levels and working memory did not change with hearing aid use. LE showed improvements in quiet but not in noise. The improvements in the SSQ were found to relate with the improvements in SNR-50.

Conclusions

The study indicated a significant perceived benefit with hearing aid acclimatization, and the underlying mechanism appears to be the signal-to-noise ratio gain. The findings of LE indicated reduced LE, thereby suggesting lesser cognitive load with hearing aid acclimatization. In addition, the individuals who performed poorer in the baseline measurement showed greater perceived benefit with hearing aid acclimatization.

Supplemental Material

https://doi.org/10.23641/asha.9253175
A Novel Stimulation Paradigm for Obtaining Interfrequency Amplitude Ratio of Ocular Vestibular Evoked Myogenic Potentials
Authors: Singh Niraj Kumar , Kumar Prawin , Jha Raghav Hira
Published: August 2019

Purpose

Interfrequency amplitude ratio (IFAR), the ratio of amplitude between ocular vestibular evoked myogenic potentials (oVEMPs) for tone bursts of 500 and 1000 Hz, aids in identification of Ménière's disease with high sensitivity and specificity. However, it requires recording of oVEMP for 2 frequencies, which doubles the time of recording. Use of simultaneous recording of responses for both frequencies could potentially bring down testing time. Simultaneous recording might be possible by modifying the oddball paradigm and using a ratio of 1:1 for the 2 frequencies. This might also reduce variation in oVEMP amplitude between frequencies due to changes in gaze angle between the recordings. However, it remains to be explored whether or not the use of modified oddball paradigm to record oVEMP (MoVEMP) will produce comparable responses to conventional sequential recording of oVEMP (CoVEMP) for obtaining IFAR. Hence, the study aimed to compare MoVEMP and CoVEMP on various measures of oVEMP.

Method

The study included 29 healthy adults in the age range of 18–30 years, 23 of which were used for validation and 6 for finding test–retest reliability. All participants underwent contralateral oVEMP recording using 500- and 1000-Hz tone bursts presented using MoVEMP and CoVEMP paradigms.

Results

Comparable outcomes on latencies, amplitude, and IFAR were obtained between CoVEMP and MoVEMP. Furthermore, MoVEMP took significantly lesser time per ear and also produced better test–retest reliability than CoVEMP.

Conclusion

MoVEMP is a quicker and more reliable clinical stimulation paradigm for obtaining IFAR than CoVEMP.
The Influence of Efferent Inhibition on Speech Perception in Noise: A Revisit Through Its Level-Dependent Function
Authors: Yashaswini L. , Maruthy Sandeep
Published: August 2019

Purpose

The study aimed to assess the relationship between the level-dependent function of efferent inhibition and speech perception in noise across different intensities of suppressor and across different signal-to-noise ratios (SNRs) of speech.

Method

Twenty-six young normal-hearing adults participated in the study. Contralateral suppression of transient evoked otoacoustic emissions (TEOAEs) was measured for 3 levels of suppressor (40, 50, and 60 dB SPL). Speech identification score (SIS) was measured at 5 ipsilateral SNR conditions (quiet, 0, −5, −10, and −15 dB), with and without contralateral broadband noise at 3 levels (40, 50, and 60 dB SPL). Furthermore, SNR-50 was measured with and without the same 3 levels of contralateral broadband noise.

Results

The results showed that the suppression magnitude of TEOAE increased with an increase in suppressor level. However, neither SIS nor SNR-50 was influenced by the contralateral noise. In addition, SIS and SNR-50 did not show significant correlation with contralateral suppression of TEOAEs. This was true at all the SNRs and contralateral noise levels used in the study.

Conclusions

The findings suggest that the intensity of noise directly influences medial olivocochlear bundle–mediated efferent inhibition. However, the role of the medial olivocochlear bundle in regulating speech perception in noise needs to be revisited.

Supplemental Material

https://doi.org/10.23641/asha.9336353
Radio loudness along the quasar main sequence
Authors: Ganci V. , Marziani P. , D’Onofrio M. , del Olmo A. , Bon E. , Bon N. , Negrete C. A.
Published: August 2019

Context.When can an active galactic nucleus (AGN) be considered radio loud (RL)? Following the established view of the AGNs inner workings, an AGN is RL if associated with relativistic ejections emitting a radio synchrotron spectrum (i.e., it is a “jetted” AGN). In this paper we exploit the AGN main sequence that offers a powerful tool to contextualize radio properties.

Aims.If large samples of optically-selected quasars are considered, AGNs are identified as RL if their Kellermann’s radio loudness ratioRK >  10. Our aims are to characterize the optical properties of different classes based on radio loudness within the main sequence and to test whether the conditionRK >  10 is sufficient for the identification of RL AGNs, since the origin of relatively strong radio emission may not be necessarily due to relativistic ejection.

Methods.A sample of 355 quasars was selected by cross-correlating the Very Large Array Faint Images of the Radio Sky at Twenty-Centimeters survey (FIRST) with the twelfth release of the Sloan Digital Sky Survey Quasar Catalog published in 2017. We classified the optical spectra according to their spectral types along the main sequence of quasars. For each spectral type, we distinguished compact and extended morphology (providing a FIRST-based atlas of radio maps in the latter case), and three classes of radio loudness: detected ( specific flux ratio in thegband and at 1.4 GHz,R′K< 10), intermediate (10 ≤R′K< 70), and RL (R′K≥ 70).

Results.The analysis revealed systematic differences between radio-detected (i.e., radio-quiet), radio-intermediate, and RL classes in each spectral type along the main sequence. We show that spectral bins that contain the extreme Population A sources have radio power compatible with emission by mechanisms ultimately due to star formation processes. RL sources of Population B are characteristically jetted. Their broad Hβprofiles can be interpreted as due to a binary broad-line region. We suggest that RL Population B sources should be preferential targets for the search of black hole binaries, and present a sample of binary black hole AGN candidates.

Conclusions.The validity of the Kellermann’s criterion may be dependent on the source location along the quasar main sequence. The consideration of the main sequence trends allowed us to distinguish between sources whose radio emission mechanisms is jetted from the ones where the mechanism is likely to be fundamentally different.
A variational formulation for computing shape derivatives of geometric constraints along rays
Authors: Feppon Florian , Allaire Grégoire , Dapogny Charles
Published: August 2019

In the formulation of shape optimization problems, multiple geometric constraint functionals involve the signed distance function to the optimized shape Ω. The numerical evaluation of their shape derivatives requires to integrate some quantities along the normal rays to Ω, a challenging operation to implement, which is usually achieved thanks to the method of characteristics. The goal of the present paper is to propose an alternative, variational approach for this purpose. Our method amounts, in full generality, to compute integral quantities along the characteristic curves of a given velocity field without requiring the explicit knowledge of these curves on the spatial discretization; it rather relies on a variational problem which can be solved conveniently by the finite element method. The well-posedness of this problem is established thanks to a detailed analysis of weighted graph spaces of the advection operator β ⋅ ∇ associated to a C1 velocity field β. One novelty of our approach is the ability to handle velocity fields with possibly unbounded divergence: we do not assume div(β) ∈ L∞. Our working assumptions are fulfilled in the context of shape optimization of C2 domains Ω, where the velocity field β = ∇dΩ is an extension of the unit outward normal vector to the optimized shape. The efficiency of our variational method with respect to the direct integration of numerical quantities along rays is evaluated on several numerical examples. Classical albeit important implementation issues such as the calculation of a shape’s curvature and the detection of its skeleton are discussed. Finally, we demonstrate the convenience and potential of our method when it comes to enforcing maximum and minimum thickness constraints in structural shape optimization.
An experimental and numerical study on vascular self-healing cementitious materials
Authors: Jefferson Anthony , Selvarajoo Tharmesh , Freeman Brubeck , Davies Robert
Published: August 2019

This paper gives an overview of a combined experimental-numerical study on vascular self-healing (SH) systems for cementitious composite materials. The work aimed to bridge the gap between numerical and experimental investigations for this type of SH system and to provide a set of data for developing, calibrating and validating a finite element model for these materials. The study investigated both healing-agent transport and mechanical damage-healing processes, including healing-agent curing. The experimental programme included mechanical tests on notched concrete beams and compact direct-tension specimens with inbuilt vascular healing systems, as well as tests to measure the transport properties of healing-agent within discrete concrete cracks and through the concrete matrix. The new coupled model employs elements with embedded strong discontinuities to simulate cracks and mechanical healing behaviour. A damage-healing constitutive model is described that simulates multiple damage-healing ‘events’. This mechanical model is coupled to discrete and continuum flow models that simulate healing-agent transport. The transport model accounts for pressurised and capillary flow, as well as curing-dependent flow properties. The main focus of this contribution is to show how these parallel programmes of work were combined so that the experimental observations guided the numerical developments and modelling questions were answered using experimental findings.
Abrasion resistance of high early-strength concrete for rapid repair
Authors: Ghafoori Nader , Maler Matthew O. , Najimi Meysam , Hasnat Ariful
Published: August 2019

This paper examines the abrasion resistance of high early-strength concrete developed for rapid repair of highways and bridge decks. The cement types chosen for this study included ASTM Type III, ASTM Type V, and Calcium Sulfoaluminate (CSA) cements. A cement content of 386 kg/m3 (650 lb/yd3) was maintained for all studied concretes. Test samples were tested after 24 hours and 28 days of curing in order to evaluate compressive strength and depth of wear. Test results revealed that the opening time to attain minimum required compressive strength for CSA cement concrete was one hour, whereas the values for Type V and Type III cement concretes were 8.5 and 6 hours, respectively. After 24 hours curing, CSA cement concrete displayed the highest strength, but lowest resistance to wear. The 28-day cured CSA cement concrete produced the highest strength and resistance to abrasion, while Type III cement concrete showed a similar strength, but lower resistance to wear, when compared to those of the Type V cement concrete.
Insights from corrosion current measurements on corrosion mechanisms in reinforced concrete and on the evaluation of other corrosion data
Authors: Schneck Ulrich
Published: August 2019

During the past years Tafel polarization measurements have been implemented into the scope of measurements of CITec corrosion diagnosis projects. This has created a vast database of different and corresponding corrosion parameters, such as chloride and water content in the rebar vicinity, open circuit potential, electrolyte resistance, polarization resistance (from galvanostatic pulse and linear polarization) and corrosion current from Tafel polarization measurements. Although general limitations in using these methods on macro cell systems such as reinforced concrete are known, the comparative assessment of these data has led to a better understanding of the corrosion behaviour and of specific circumstances of the structures which deviated partly from usual expectations. For instance, a low polarization resistance at high chloride content will not result necessarily in a high corrosion current, if the reinforcement in the wider vicinity of the test location is similar active, and cathodic rebar areas are either very distant or retarded by very wet concrete. So the extended range of corrosion testing gives a more precise evaluation of the corrosion situation and permits a tailored repair and maintenance concept to be found. It has also been found that the Stern-Geary equation which is often used to calculate corrosion current densities and material loss of the reinforcement from linear polarization (LPR) measurements, doesn’t seem very feasible if used on reinforced concrete structures, as there appears to be a dominant influence of macro cell corrosion over the corrosion model of a homogenous mixed electrode (for which the Stern-Geary equation applies), and the true corrosion current densities may be either larger or (very often) much smaller than those calculated from Stern-Geary. This is not a new observation, and the findings will be discussed for several project cases.
Corrosion protection of steel reinforcement by using surface applied corrosion inhibitors
Authors: Seyhan Engin Cueneyt , Goodwin Fred , Huang I-Wen (Evan)
Published: August 2019

Surface applied corrosion inhibitors (SACI) are widely used to mitigate the corrosion process of steel reinforcement in concrete. But they remain controversial as to their effectiveness and the ability to compare materials from different manufacturers and technologies. They are applied onto the surface of hardened concrete and penetrate towards the steel reinforcement. This paper discusses the corrosion inhibition performances of a dual-phase corrosion inhibitor and field surveys through corrosion monitoring the selected structures. The efficiency of the corrosion inhibitor is assessed by selected testing procedures in laboratories.
Estimation of In-situ concrete strength using drilling resistance
Authors: Karatosun Serkan , Asan Muhammet , Gunes Oguz
Published: August 2019

Rapid and reliable condition assessment of reinforced concrete structures in high seismicity regions is a priority task in estimating their seismic safety. Non-destructive testing (NDT) methods may contribute to the condition assessment practice by providing fast and reliable strength estimation while causing minimal or no damage to the structure. Drilling resistance is an NDT method that has been used for mechanical characterization of natural stone and wood by measuring the force response for constant penetration rate and rotational speed. This paper focuses on the relationship between drilling resistance and compressive strength of concrete, including when it is combined with other NDT methods. Concrete cube samples produced using 6 different concrete mixtures were tested. Correlation equations were then obtained using statistical analysis. The results reveal that it may be possible to reliably estimate the compressive strength of concrete using drilling resistance method.
Comparison of 2D and 3D ultrasonic pulse echo imaging techniques for structural assessment.
Authors: Misak Lubos , Corbett David , Grantham Michael
Published: August 2019

The use of ultrasonic waves in the medical field is quite advanced, especially in the area of three-dimensional (3D) imaging of the human body and is quite common. Also, in Non-Destructive Testing of metal (for example weld checking), flaw detection with reliable 3D imaging is already in use. In the past 1 -2 years, the construction industry has made significant advances in two-dimensional (2D) and three-dimensional (3D) imaging of concrete structures, for finding problems, or irregularities inside, or just for confirming the quality of the construction work. This paper describes the principles of the different types of scan, A Scan, B Scan etc and how the scans can be combined to make 3D images. The advantages of multi head array systems in providing more detail and revealing depth information are shown. This paper will show the advantages of this development and how it can ease workflow.
Pretensioned BFRP reinforced concrete beams: Flexural behaviour and estimation of initial prestress losses
Authors: Pavlović Ana , Donchev Ted , Petkova Diana , Limbachiya Mukesh , Almuhaisen Refad
Published: August 2019

Fibre Reinforced Polymers (FRP) are becoming a popular reinforcement option for RC elements mainly due to good strength to weight ratio and resistance to corrosion. The main limitation for their wider application is their relatively low Young’s modulus, which results in unfavourable serviceability performance, in terms of early development of deflections and cracks. Among others, prestressing has been suggested as one of the possible approaches to addressing this issue, with encouraging results from research conducted so far. This experimental study aimed to explore prestress losses of basalt fibre reinforced polymer (BFRP) reinforced pretensioned concrete beams. Five beams were produced, three of them internally reinforced with 6mm diameter BFRP bars, pretensioned to 20%, 30% and 40% of the ultimate load level of prestress. Additionally, two beams, acting as control samples, were reinforced with unprestressed BFRP and steel bars of same cross-sectional area, respectively. The dimensions of all samples were 125x200x1900 mm. Prestress losses were monitored with the aid of strain gauges attached to the reinforcing bars, as well as load cells. The strain readings were continuously taken during the pretensioning process, from initial application of the prestressing force, during casting and curing of concrete, until releasing of the beams from prestressing devices after curing. Ultimately, all samples were subjected to a quasi-static, load-controlled, four-point bending test until destruction. The results provide the information about the flexural behaviour of pretensioned BFRP reinforced beams, along with insight into some of the initial prestress losses of these elements.
Development of sustainable concrete repair materials via microencapsulated agents
Authors: Litina Chrysoula , Al-Tabbaa Abir
Published: August 2019

Identification of non-structural damage in concrete infrastructure and actuation of preventive repair solutions is an established approach to avoid further structural damages and more expensive repair regimes. However the repair of concrete itself is not infallible with 55% of reported repairs in the EU failing within 5 years of service. Thus the already once repaired concrete structure is then subject to a constant cycle of repeated repair and a cumulative associated life cycle cost. The development of external repair material with self-healing capabilities, can affect a real step-change on the life-cycle costs and maintenance of existing and new infrastructure. Developed polymeric microcapsules containing liquid sodium silicate were used to impart autonomic self-healing to readily available commercial repair mortars for the first time. These materials cover a range of potential real time repair applications. Initially the compatibility between the developed self-healing agents and commercial products was established and the self-healing performance of the novel composite system was then evaluated. The results underlined the huge potential for the proposed composite systems as a stepping stone toward commercial uptake of self-healing microcapsule-based cementititious materials.
Guidance and Control Method for Vehicle with Strap-down Seeker
Authors: Fugui Li , Shengwei Jia , Zeyou Tong , Changjian Zhao , Yahui Li , Feng Gao , Min Gong
Published: August 2019

Guidance and control method was presented in this paper for flight vehicle with a strap-down seeker. Firstly, an extended Kalman filter was constructed in LOS (line of sight) coordinate system to estimate the guidance signal based on the information measured by strap-down seeker and inertial measurement unit. Secondly, an optimal guidance law which could reduce the target maneuvering and guidance system dynamics was proposed. Thirdly, three-loop acceleration autopilot with pseudo-angle of attack feedback was presented to control the flight vehicle. Finally, the proposed methods were simulated under typical condition. The simulation results demonstrated that the proposed methods were valid, and good performance could be achieved by the guidance and control method with the guidance signal estimated by the extended Kalman filter.
Statistical Analysis of Aviation Accidents and Incidents Caused by Failure of Hydraulic Systems
Authors: Woch Marta , Zieja Mariusz , Tomaszewska Justyna , Janicki Mateusz
Published: August 2019

In the era of globalization and permanent travel of people between far away regions of the world, air transport is one of the most important means of transport. Today it is also one of the most secure transport modes possibilities. Despite this, it is crucial to continuously improve the level of safety and reduce the absolute number of accidents and their victims. This idea stands at the beginning of the article subject creation and at the same time an attempt to further improve safety. The safety of the pilots and passengers plays a crucial role during air operations. One of the most important factors is the reliability of the aircraft. The main goal in the reliability work is to estimate the percentage of units of a product that will still be functioning after a particular period of time. In order to be able to make such a statement, it is necessary to select a probability distribution that will facilitate the construction of reasonably precise probability statements of the type that one wishes to make. In this analysis, the number of hours between failures has been used as the main variable for reaching the conclusion about the reliability of the aircraft at the selected examples.
Investigation of Slip Occurrence in the Ring Rolling Process
Authors: Gontarz Andrzej , Surdacki Piotr
Published: August 2019

Ring rolling is a hot forming process for producing rings that have large diameters when compared to their cross sections. This process is very dynamic and involves considerable variations in ring shape and size. One of the failure modes in ring rolling processes is slip that occurs when a thickness reduction, exceeds the limit value. The thickness reduction depends on the tool speed and dimensions as well as ring size, and varies over time. This paper reports results of a study investigating the thickness reduction with respect to slip occurrence. In terms of wall thickness reduction, the process can be divided into three distinct stages (excluding the sizing stage): (i) initial stage corresponding to the first revolution of the roll, (ii) main stage, when the proper ring rolling takes place, (iii) final stage, when the main roll does not move in an axial direction but the ring is being formed during one revolution of the tool. It has been found that the most slip-prone moment is the end of the second and the beginning of the third stage of the ring rolling process, when the wall thickness reduction is the highest. Based on a comparison of the calculated thickness reduction and its limit values, it could be predicted whether slip would occur, and if so – in what stage of the rolling process. Numerical results and experimental findings are in good agreement.
Practical Application of the Aqueous ‘Sulfonyl-Azide-Free’ (SAFE) Diazo Transfer Protocol to Less α-C–H Acidic Ketones and Esters
Authors: Dar’in Dmitry , Kantin Grigory , Krasavin Mikhail
Published: August 2019

The earlier described ‘sulfonyl-azide-free’ (‘SAFE’) protocol for diazo transfer to CH-acidic 1,3-dicarbonyl compounds (and their similarly activated congeners) has been extended to the less reactive monocarbonyl substrates, which previously required a separate activation step. Formylation in situ, followed by the addition of an optimized amount of the ‘SAFE cocktail’ (obtained by mixing sodium azide, potassium carbonate, and m-carboxybenzenesulfonyl chloride in water) led to the formation of the desired diazo compounds, which were isolated by extraction in moderate to excellent yields, and, in most cases, with no need for additional purification.
Antibacterial and Remineralization Efficacy of Casein Phosphopeptide, Glycomacropeptide Nanocomplex, and Probiotics in Experimental Toothpastes: An In Vitro Comparative Study
Authors: Elgamily Hanaa , Safwat Engie , Soliman Zainab , Salama Heba , El-Sayed Hoda , Anwar Mohamed
Published: August 2019

Objective This article evaluates the antibacterial and remineralization potential of experimentally prepared toothpastes containing different mixtures of nano casein phosphopeptides (nCPP), nano amorphous calcium phosphate (nACP), probiotic ­ Lactobacillus rhamnosus B-445 (L. rhamnosus), and nano glycomacropeptide (nGMP).

Materials and Methods Five experimental toothpaste samples were prepared and grouped, such that group (A0) was the experimental toothpaste base formula. Groups (A1), (A2), (A3), and (A4) were the experimental toothpastes containing: nCPP; nCPP and nACP; nCPP, nACP, and L. rhamnosus, and nCPP, nACP, and nGMP, ­respectively. Group (A5) was the commercial group (GC MI Paste Plus). The five groups were screened against Streptococcus mutans (ATCC 25175) growth, and investigated for their remineralizing potentials on demineralized bovine enamel using Vickers ­microhardness test (Vickers hardness number [VHN]). Scanning electron microscope (SEM) images were obtained for the demineralized and remineralized enamel of the two most effective toothpastes against in vitro bacterial induced enamel demineralization. Statistical analysis was performed using one-way analysis of variance (ANOVA) as well as repeated measures ANOVA followed by Tukey’s post hoc test.

Results Both (A3) and (A4) were significantly higher in mean inhibition zone ­diameters than group (A1) and (A2). Group (A4) showed the highest statistical ­significance in the mean difference between VHN values of demineralization and 15 days remineralization period. SEM images showed the deposition of nano-sized particles fill the ­microrough surface pattern of the etched enamel.

Conclusion All these findings suggest the use of probiotic, nCPP–nACP, and nGMP as a dental anticariogenic and remineralizing active agents.
Nurses' Expectations of an Inpatient Portal for Hospitalized Patients and Caregivers
Authors: Hoonakker Peter L. T. , Rankin Rebecca J. , Passini Jennifer C. , Bunton Jenny A. , Ehlenfeldt Bradley D. , Dean Shannon M. , Thurber Anne S. , Kelly Michelle M.
Published: August 2019

Background Patient portals are intended to engage patients and enhance patient-centered care. Recent studies suggest that the information within portals could provide benefits to patients and their caregivers during hospitalization; however, few studies have examined nurse and staff expectations of portals when used in the hospital setting.

Objective This article examines inpatient nurse and support staff expectations of a commercially available inpatient portal prior to its hospital-wide implementation.

Methods In this cross-sectional study, nurses and support staff were surveyed 1 month prior to the implementation of an inpatient portal for patients. Items included respondent characteristics, satisfaction with online inpatient portal training, expectations of the effects of portal use on patients, caregivers, and staff, overall acceptance, and barriers to its implementation.

Results Of 881 respondents, 73.0% were staff nurses, 18.4% nurse assistants, 4.3% unit coordinators, and 1.2% nurse managers. Respondents were generally satisfied with the portal information they received from online training. A majority liked the portal to some extent prior to its use (66.7%); however, they noted multiple implementation barriers, including: tablets would get lost/damaged (66.2% of respondents), patients and/or caregivers would have too many questions (48.5%), and staff would have problems integrating it into their workflow (44.7%). Respondents working on medical units had higher expectations (p < 0.001) and acceptance (p < 0.01) of the portal than those on surgical and intensive care units. Nurse managers were more positive than respondents with other job roles were (all p < 0.001).

Conclusion Overall, nurse and support staff had high expectations of the effects of inpatient portal use prior to its hospital-wide implementation. They thought it would benefit patients and/or their caregivers; however, they also perceived several barriers to its implementation. These results will be used in conjunction with patient and caregiver perspectives to inform future efforts to evaluate and improve upon inpatient portal implementation and dissemination across health systems.
Well-posedness and scattering of inhomogeneous cubic-quintic NLS
Authors: Cho Yonggeun
Published: August 2019

In this paper, we consider inhomogeneous cubic-quintic nonlinear Schrödinger (ICQNLS) in space dimension d = 3, iut = −Δu + K1(x)|u|2u + K2(x)|u|4u. We study local well-posedness, finite time blowup, and small data scattering and nonscattering for the ICQNLS when K1,K2∈C4(R3\{0}) satisfy growth condition |∂jKi(x)|≲|x|bi−j (j=0,1,2,3,4) for some bi ≥ 0 and for x ≠ 0. To this end, we use the Sobolev inequality for the functions f ∈ Hn (n = 1, 2) such that ‖|L|ℓf‖Hn<∞ (ℓ=1,2), where L is the angular momentum operator defined by L = x × (−i∇).
Multi-objective optimization of a thick blade root airfoil to improve the energy production of large wind turbines
Authors: Herrmann Jordis , Bangga Galih
Published: August 2019

With the growing need for renewable energy, the size of wind turbines is significantly increasing nowadays. This enforces blade designers to employ much thicker airfoils than conventional turbines to provide the necessary structural strength with reduced aerodynamic performance. In the present work, a numerical optimization process employing a genetic algorithm approach for the thick DU 00-W-401 airfoil has been applied to improve its aerodynamic performance, making it suitable for large wind turbine rotors. The maximal relative thickness of the airfoil is kept constant at 40% to retain the structural strength, and the trailing edge remains sharp to avoid a significant drag increase. The optimization is conducted under both clean and soiled conditions. Ten different objective functions are compared with each other, and several parametric studies are conducted on the optimal setting of the user variables. More than 900 data points are simulated. The airfoil has a wider operating regime than the baseline airfoil. For the soiled condition case, the airfoil clearly shows improved characteristics. The optimized airfoil is confirmed to improve the overall aerodynamic performance. Further quantification of the cost of energy generated by the optimized airfoil is carried out taking into account the 3D effects.
Effects of the guide field on electron distribution functions in the diffusion region of asymmetric reconnection
Authors: Bessho N. , Chen L.-J. , Wang S. , Hesse M.
Published: August 2019

Crescent electron distribution functions in the electron diffusion region in asymmetric reconnection with a guide field (strength less than 50% of the upstream magnetic field) are investigated by theory and fully kinetic simulations. Electron motion in the electron diffusion region is a combination of meandering across the current sheet and gyration around the guide field. Combining the two canonical momentum conservation laws in a one-dimensional model with the energy conservation law, we derive the shape of crescent electron distribution functions in both velocity planes: perpendicular to the magnetic field and coplanner with the magnetic field. There are two major effects of the guide field on crescent distribution functions: (1) widening the opening angle of the crescent in a reduced distribution function and (2) the linear cut-off of a distribution function nonparallel to the magnetic field. We also discuss a translational mapping (perpendicular to the linear cut-off) of distribution functions between the X-line and another position. In addition, considering the gyration due to the normal magnetic field, we predict the shape of distribution functions in general positions in the electron diffusion region. The predictions will be useful to identify features of magnetic reconnection in a guide field by satellite observations.
Homogenization of nonlinear equations with mixed boundary conditions
Authors: Zhao Jie , Wang Juan
Published: August 2019

In this paper, we will study the convergence rates of solutions for homogenization of quasilinear elliptic equations with the mixed Dirichlet-Robin boundary conditions. Thanks to the smoothing operator as well as homogenization tools, we could handle the different boundary conditions in a uniform fashion. As a consequence, we establish the sharp rates of convergence in H1 and L2, which may be regarded as an extension from the classical linear equations Dirichlet or Neumann problems to a nonlinear case with the mixed boundary settings.
A theory of average response to large jump perturbations
Authors: Abramov Rafail V.
Published: August 2019

A key feature of the classical Fluctuation Dissipation theorem is its ability to approximate the average response of a dynamical system to a sufficiently small external perturbation from an appropriate time correlation function of the unperturbed dynamics of this system. In the present work, we examine the situation where the state of a nonlinear dynamical system is perturbed by a finitely large, instantaneous external perturbation (jump), for example, the Earth climate perturbed by an extinction level event. Such jump can be either deterministic or stochastic, and in the case of a stochastic jump its randomness can be spatial, or temporal, or both. We show that, even for large instantaneous jumps, the average response of the system can be expressed in the form of a suitable time correlation function of the corresponding unperturbed dynamics. For stochastic jumps, we consider two situations: one where a single spatially random jump of a system state occurs at a predetermined time, and the other where jumps occur randomly in time with small space-time dependent statistical intensity. For all studied configurations, we compute the corresponding average response formulas in the form of suitable time correlation functions of the unperturbed dynamics. Some efficiently computable approximations are derived for practical modeling scenarios.
Femtosecond pulsed laser deposited Er3+-doped zinc-sodium tellurite glass on Si: Thin-film structural and photoluminescence properties
Authors: Mann Thomas , Richards Billy , Kumi-Barimah Eric , Mathieson Robert , Murray Matthew , Ikonic Zoran , Steenson Paul , Russell Christopher , Jose Gin
Published: August 2019

We characterise the thin-film structural properties and photoluminescence of femtosecond (40 fs, 800 nm) pulsed laser deposited Er3+-doped zinc-sodium tellurite glass on Si as a function of laser fluence. The laser fluence regime required for the formation of films composed of nanoparticles without droplets is found, the composition and crystallinity of the deposited material is reported and the photoluminescence of the films is characterised in dependence of film thickness.
Impact of targeted attack on the spontaneous activity in spatial and biologically-inspired neuronal networks
Authors: Faci-Lázaro Sergio , Soriano Jordi , Gómez-Gardeñes Jesús
Published: August 2019

We study the structural and dynamical consequences of damage in spatial neuronal networks. Inspired by real in vitro networks, we construct directed networks embedded in a two-dimensional space and follow biological rules for designing the wiring of the system. As a result, synthetic cultures display strong metric correlations similar to those observed in real experiments. In its turn, neuronal dynamics is incorporated through the Izhikevich model adopting the parameters derived from observation in real cultures. We consider two scenarios for damage, targeted attacks on those neurons with the highest out-degree and random failures. By analyzing the evolution of both the giant connected component and the dynamical patterns of the neurons as nodes are removed, we observe that network activity halts for a removal of 50% of the nodes in targeted attacks, much lower than the 70% node removal required in the case of random failures. Notably, the decrease of neuronal activity is not gradual. Both damage scenarios portray “boosts” of activity just before full silencing that are not present in equivalent random (Erdös–Rényi) graphs. These boosts correspond to small, spatially compact subnetworks that are able to maintain high levels of activity. Since these subnetworks are absent in the equivalent random graphs, we hypothesize that metric correlations facilitate the existence of local circuits sufficiently integrated to maintain activity, shaping an intrinsic mechanism for resilience.
Gasistor: A memristor based gas-triggered switch and gas sensor with memory
Authors: Vidiš Marek , Plecenik Tomáš , Moško Martin , Tomašec Samuel , Roch Tomáš , Satrapinskyy Leonid , Grančič Branislav , Plecenik Andrej
Published: August 2019

Capacitorlike metal/metal oxide/metal structures are widely used as resistive switching cells and are utilized in resistive random access memories. Recently, it has been demonstrated that they also perform well as gas sensors. In this work, we have merged the gas sensing and resistive switching capabilities of the capacitorlike Pt/TiO2/Pt structures to constitute a simple device which works as a gas-triggered thyristorlike switch and as a gas sensor with a built-in memory.
Convergence patterns and rates in two-state perturbation expansions
Authors: Olsen Jeppe , Jørgensen Poul
Published: August 2019

A simple two-state model has previously been shown to be able to describe and rationalize the convergence of the most common perturbation method for including electron correlation, the Møller-Plesset expansion. In particular, this simple model has been able to predict the convergence rate and the form of the higher-order corrections for typical Møller-Plesset expansions of the correlation energy. In this paper, the convergence of nondegenerate perturbation expansions in the two-state model is analyzed in detail for a general form of two-state perturbation expansion by examining the analytic expressions of the corrections and series of the values of the corrections for various choices of the perturbation. The previous analysis that covered only a single form of the perturbation is thereby generalized to arbitrary forms of the perturbation. It is shown that the convergence may be described in terms of four characteristics: archetype, rate of convergence, length of recurring period, and sign pattern. The archetype defines the overall form of a plot of the energy-corrections, and the remaining characteristics specify details of the archetype. For symmetric (Hermitian) perturbations, five archetypes are observed: zigzag, interspersed zigzag, triadic, ripples, and geometric. Two additional archetypes are obtained for an asymmetric perturbation: zigzag-geometric and convex-geometric. For symmetric perturbations, each archetype has a distinctive pattern that recurs with a period which depends on the perturbation parameters, whereas no such recurrence exists for asymmetric perturbations from a series of numerical corrections. The obtained relations between the form of a two-state perturbation and the energy corrections allow us to obtain additional insights into the convergence behavior of the Møller-Plesset and other forms of perturbation expansions. This is demonstrated by analyzing several diverging or slowly converging perturbation expansions of ground state and excitation energies. It is demonstrated that the higher-order corrections of these expansions can be described using the two-state model and each expansion can therefore be described in terms of an archetype and the other three characteristics. Examples of all archetypes except the zigzag and convex-geometric archetypes are given. For each example, it is shown how the characteristics may be extracted from the higher-order corrections and used to identify the term in the perturbation that is the cause of the observed slow convergence or divergence.
Possible high Tc superconductivity in the doped channel of a field effect transistor
Authors: Sahraoui-Tahar M.
Published: August 2019

We predict high Tc superconductivity in the doped channel of a field effect transistor; where the electron-phonon interaction is due to the Jahn-Teller effect. An analytic expression of the electron-phonon interaction constant is derived; and the McMillan formula is used to estimate the transition temperature in semiconductors with different Debye temperatures. Experiments are also suggested.
A project of advanced solid-state neutron polarizer for PF1B instrument at Institut Laue-Langevin
Authors: Petukhov A. K. , Nesvizhevsky V. V. , Bigault T. , Courtois P. , Jullien D. , Soldner T.
Published: August 2019

Among polarizers based on the neutron reflection from Super-Mirrors (SMs), solid-state neutron-optical devices have many advantages. The most relevant is the 5–10 times smaller size along the neutron beam direction compared to more traditional air-gap devices. An important condition for a good SM polarizer is the matching of the substrate SLD (Scattering Length Density) with the SM coating SLD for the spin-down component. For traditional Fe/Si SM on the Si substrate, this SLD step is positive when a neutron goes from the substrate to the SM, which leads to a significant degradation of the polarizer performance in the small Q region. This can be solved by replacing single-crystal Si substrates by single-crystal sapphire or quartz substrates. The latter shows a negative SLD step for the spin-down neutron polarization component at the interface with Fe and, therefore, avoid the total reflection regime in the small Q region. In order to optimize the polarizer performance, we formulate the concept of sapphire V-bender. We perform ray-tracing simulations of sapphire V-bender, compare results with those for traditional C-bender on Si, and study experimentally V-bender prototypes with different substrates. Our results show that the choice of substrate material, polarizer geometry, as well the strength and quality of magnetizing field have dramatic effect on the polarizer performance. In particular, we compare the performance of polarizer for the applied magnetic field strength of 50 mT and 300 mT. Only the large field strength (300 mT) provides an excellent agreement between the simulated and measured polarization values. For the double-reflection configuration, a record polarization >0.999 was obtained in the neutron wavelength band of 0.3–1.2 nm with only 1% decrease at 2 nm. Without any collimation, the polarization averaged over the full outgoing capture spectrum, 0.997, was found to be equal to the value obtained previously using only a double polarizer in the “crossed” (X-SM) geometry. These results are applied in a full-scale polarizer for the PF1B instrument.
Direct measurement of anisotropic conductivity in a nanolaminated (Mn0.5Cr0.5)2GaC thin film
Authors: Flatten Tim , Matthes Frank , Petruhins Andrejs , Salikhov Ruslan , Wiedwald Ulf , Farle Michael , Rosen Johanna , Bürgler Daniel E. , Schneider Claus M.
Published: August 2019

The direct and parameter-free measurement of anisotropic electrical resistivity of a magnetic Mn+1AXn (MAX) phase film is presented. A multitip scanning tunneling microscope is used to carry out 4-probe transport measurements with variable probe spacing s. The observation of the crossover from the 3D regime for small s to the 2D regime for large s enables the determination of both in-plane and perpendicular-to-plane resistivities ρab and ρc. A (Cr0.5Mn0.5)2GaC MAX phase film shows a large anisotropy ratio ρc/ρab=525±49. This is a consequence of the complex bonding scheme of MAX phases with covalent M–X and metallic M–M bonds in the MX planes and predominately covalent, but weaker bonds between the MX and A planes.
Theoretical Energy Levels of 1sns
and 1snp
States of Helium-Like Ions
Authors: Yerokhin V. A. , Surzhykov A.
Published: August 2019

Energy levels of the 1sns and 1snp states of ions along the helium isoelectronic sequence from carbon to uranium are calculated, with n = 3–7. The computation is performed within the relativistic configuration-interaction method, including the relativistic nuclear recoil effect, the leading quantum electrodynamics effects, and the frequency dependence of the Breit interaction. All theoretical energies are supplied with uncertainty estimates.