Phase Factor Research Articles

Determination of mutual diffusivity of CO2/C3H8-heavy oil systems with consideration of natural convection under reservoir conditions

By performing dynamic volume analysis, we developed and applied an experimental and theoretical technique to determine mutual diffusivity (i.e., diffusivity of a gas component in an oil phase and that of the extracted oil components in the gas phase) of CO2/C3H8-heavy oil systems in the presence of natural convection under reservoir conditions. Experimentally, diffusion tests are conducted for CO2/C3H8-heavy oil systems at high pressures and elevated temperatures with a PVT setup, while swelling factors of the oil phase are measured and recorded continuously. We have collected gas and oil samples at end of the test for gas chromatography (GC) and oil compositional analysis. Theoretically, mutual diffusivity between a solvent and heavy oil can be determined once the discrepancies between the measured and calculated parameters, including swelling factors and gas compositions, have been minimized. The diffusivities of both solvents (i.e., CO2 and C3H8) and oil components are found to increase with pressure and temperature. Except for the dissolution of solvent(s) into heavy oil due to concentration difference, there exists an obvious extraction process from the oil to gas phases during each experiment at elevated temperatures as light-medium components (i.e., C1-C4 and C6-C8) have been detected in the collected gas samples at the end of the test, during which the oil swelling effect is diminished at its late period when the solvent-heavy oil system approaches its equilibrium state. Compared to the CO2-heavy oil systems, more light components have been detected for the C3H8-heavy oil systems, indicating that stronger extraction occurs when adding C3H8 to the heavy oil at elevated temperatures. Since natural convection has an opposite direction from molecular diffusion, separating the former from the latter results in larger diffusion coefficients of CO2 and C3H8. In addition to new experimental data, both diffusivity of a solvent/CO2 in heavy oil and that of the extracted oil components in the gas phase are quantified in a more complex solvent(s)/CO2-heavy oil system at high pressures and elevated temperatures, not only serving as the benchmark for future studies to consider the contribution of temperature and porous media, but also allowing us to evaluate and optimize the hybrid solvent-steam method in a heavy oil reservoir within a unified and consistent framework.

Opportunities and challenges in lung cancer screening implementation: a narrative review

: The U.S. Preventive Services Task Force and the Centers for Medicare and Medicaid Services (CMS) recommend lung cancer screening (LCS) for high risk current and former smokers. Developing a comprehensive LCS program requires coordinated planning from program conception through implementation and maintenance that address both pragmatic and regulatory matters. In this review article, we discuss the available evidence, guideline recommendations, and practical considerations for implementing a high-quality LCS program. Key factors in the initial planning phase include engagement of stakeholders with a particular focus on support from providers, patients and healthcare organizations. Additionally, it is important to consider the infrastructure and program design that will best serve local needs, and implement mandatory components such as a data registry and smoking cessation. We also discuss the implementation phase including strategies for optimizing the eligible patient population to be screened as well as the processes of shared decision making (SDM), standardization of screening results and communication of findings to patients. Once patients have been screened, maintenance of a successful LCS program requires iterative multidisciplinary reviews of key quality metrics and establishing systematic mechanisms to track evaluation, minimizing loss to follow-up. We also review other recommended components that contribute to maintaining a high-quality screening program such as a clinical screening coordinator, patient navigator, and tools to improve the uptake of and adherence to LCS.

Enhanced EIG in microwave controlled X-type atomic system

A microwave driven five-level X-type atomic system is proposed to diffract weak probe light into higher-order directions via the phenomenon of electromagnetically induced grating. In the proposed scheme, the effect of various system and field parameters on its higher-order diffraction efficiency is studied. The present atomic scheme offers excellent control over higher-order diffraction intensities by utilizing the microwave induced quantum interference effect. It is observed that the desired first-order diffraction efficiency can be attained through optimal selection of microwave field strength and relative phase factor.

Spin-wave-based tunable coupler between superconducting flux qubits

Quantum computing and simulation based on superconducting qubits have achieved significant progress and entered the noisy intermediate-scale quantum (NISQ) era recently. Using a third qubit or object as a tunable coupler between qubits is an important step in this process. In this article, we propose a hybrid system made of superconducting qubit and a yttrium iron garnet (YIG) system as an alternative way to realize this. YIG thin films have spin wave (magnon) modes with low dissipation and reliable control for quantum information processing. Here, we propose a scheme to achieve strong coherent coupling between superconducting (SC) flux qubits and magnon modes in YIG thin film. Unlike the direct $\sqrt{N}$ enhancement factor in coupling to the Kittel mode and other spin ensembles, with $N$ the total number of spins, an additional spatial-dependent phase factor needs to be considered when the qubits are magnetically coupled with the magnon modes of finite wavelength. To avoid undesirable cancellation of coupling caused by the symmetrical boundary condition, a CoFeB thin layer is added to one side of the YIG thin film to break the symmetry. Our numerical simulation demonstrates avoided crossing and coherent transfer of quantum information between the flux qubit and the standing spin waves in YIG thin films. We show that the YIG thin film can be used as a tunable coupler between two flux qubits, which have a modified shape with small direct inductive coupling between them. Our results manifest that by cancellation of direct inductive coupling and indirect spin-wave couple of flux qubits we can turn on and off the net coupling between qubits. This bring magnonic YIG thin film into the field of quantum information processing.

Shipbuilding Decision-Making Optimization Based on the Functional Technical Documentation Information Level Usage in Ship Production

_ Decision-makers in shipyards face the problem of determining the design cost concerning the information level contained in drawing and how it influences the shipbuilding process efficiency. Shipyards have their approach and shipbuilding practices about the level of functional technical documentation usage directly in ship production. However, decisions may vary related to the ship type, complexity, size, and deadlines. The shipbuilding decision-making optimization model based on functional technical documentation defines an algorithm for creating and analyzing the data representing the effects of applying functional technical documentation in ship production. Based on such analysis, it is possible to decide the preferred shipbuilding strategy, based on the level of functional technical documentation usage directly in ship production at the level other than one identified in the ship contractual stage, reducing overall shipbuilding costs. By varying different factors of the technological phase of ship production and the relative labor cost with the level of functional technical documentation usage directly in ship production, the curves of the shipbuilding cost and duration deviations, in relation with the value specified by the reference point, are obtained. Also, such analysis provides relevant conclusions about the trend of losses or savings of budget and labor hours based on the level of functional technical documentation usage directly in ship production.

Single-pixel phase microscopy without [formula omitted] system

We present single-pixel phase microscopy (SPPM) without 4f system, as a novel common-path quantitative phase imaging method, to acquire the amplitude and phase of any transmissive object. To get rid of the 4f system and make the experimental setup more compact and practical, SPPM adopts the phase-modulated detection mode. A single microscopy objective is employed for image magnification, and a collecting lens is used to circumvent the quadratic phase factor introduced by the objective. A phase-only liquid crystal on silicon is utilized to modulate the phase of object light to achieve Hadamard basis scan phase imaging and Fourier basis scan phase imaging with a single photomultiplier tube. We apply SPPM to observe several different types of objects, from simple artificial objects to complex biological specimens. The experimental results show that SPPM provides clear imaging, accurate phase, and spatial resolution up to 2.19 µm (a spatial frequency of 456 lp/mm). Without the 4f system, SPPM can be implemented as an add-on module to existing optical microscopy, which facilitates its adoption in biomedical science and optical metrology.

Generation of modulated magnetic structures based on cluster multipole expansion: Application to α -Mn and CoM3S6

We present a systematic method to automatically generate symmetry-adapted magnetic structures for given crystal structure and general propagation vector k as an efficient approach of the analysis of complex modulated magnetic structures. The method is developed as an extension of the generation scheme based on multipole expansion, which was demonstrated only for the propagation vector k=0 [M.-T. Suzuki et al., Phys. Rev. B 99, 174407 (2019)]. The symmetry-adapted magnetic structures characterized with an ordering vector k are obtained by mapping the multipole magnetic alignments on a virtual cluster to the periodic crystal structure with the phase factor for the wave vector k. This method provides all magnetic bases compatible with irreducible representations under k-group for given crystal structure and wave vector k. Multiple-k magnetic structures are derived from superposition of single-k magnetic bases related with space group symmetry. We apply the scheme to deduce the magnetic structures of $\alpha$-Mn and Co$M_{3}$S$_6$ (M = Nb, Ta), in which large anomalous Hall effect has recently been observed in antiferromagnetic phases, and identify the magnetic structures inducing anomalous Hall effect without net magnetization. The physical phenomena originating from emergent multipoles in the ordered phases are also discussed based on the Landau theory.

Antipodal angular correlations of inflationary stochastic gravitational wave background

The measurement of the inflationary stochastic gravitational-wave background (SGWB) is one of the main goals of future GW experiments. In direct GW experiments, an obstacle to achieving it is the isolation of the inflationary SGWB from the other types of SGWB. In this paper, as a distinguishable signature of the inflationary SGWB, we argue the detectability of its universal property: antipodal correlations, i.e., correlations of GWs from the opposite directions, as a consequence of the horizon re-entry. A phase-coherent method has been known to be of no use for detecting the angular correlations in SGWB due to a problematic phase factor that erases the signal. We thus investigate whether we can construct a phase-incoherent estimator of the antipodal correlations in the intensity map. We found that the conclusion depends on whether the inflationary GWs have statistical isotropy or not. In the standard inflationary models with statistical homogeneity and isotropy, there is no estimator that is sensitive to the antipodal correlations but does not suffer from the problematic phase factor. On the other hand, it is possible to find a non-vanishing estimator of the antipodal correlations for inflationary models with statistical anisotropy. SGWB from anisotropic inflation is distinguishable from the other components.

Parameters for ferroelectric phase stabilization of sputtered undoped hafnium oxide thin films

In this work, various stabilization factors for the ferroelectric phase of undoped hafnium oxide prepared by physical vapour deposition were investigated. The capping of the thin films with platinum top electrodes before annealing, as well as the amount of oxygen during sputter deposition and subsequent annealing was shown to have a significant influence on the resulting ferroelectric properties and phase of the HfO x layer. When the prepared films were not capped, only one specific set of process parameters was found to lead to the formation of the ferroelectric phase. We conclude that capping is a crucial condition for stabilizing the ferroelectric phase. Furthermore, it is shown that the amount of oxygen supply during all fabrication processes determines the resulting ferroelectric phase fraction for capped samples. Increasing the oxygen flow during sputtering and annealing results in a larger monoclinic phase fraction and thus a decrease of the remanent polarization.

MAGNETIC FIELD-DEPENDENT ELECTRIC CURRENT ON A PERIODIC POLY(DA)-POLY(DT) DNA MOLECULE STRUCTURE

An electric current flowing on the Poly(dA)-poly(dT) DNA molecule structure has been calculated. The current was calculated from transmission probabilities by employing Landauer-Buttiker formalism. Green’s function technique has been used for obtaining the transmission probabilities. The DNA molecule structure was modeled within the tight-binding Hamiltonian model approach. The model takes into account electron hopping parameters which are dependent on the magnetic field as well as the electric field. The presence of a magnetic field causes the Peierls phase factor on the electron hopping parameters. The calculation results at low electric voltages show that after decreasing, the electric current oscillates with the magnetic field. However, at higher electric voltages, the electric current is increasing and oscillates with the magnetic field.

Sampling at Twice the Nyquist Rate in Two Frequency Bins Guarantees Uniqueness in Gabor Phase Retrieval

We show that bandlimited signals can be uniquely recovered (up to a constant global phase factor) from Gabor transform magnitudes sampled at twice the Nyquist rate in two frequency bins.

RELIEF, REGRETS, AND REINVENTION: LIFE AFTER GRAY DIVORCE

Abstract “Gray divorce,” or divorce which occurs in later life, is rapidly becoming more common in the United States. The purpose of this grounded theory study was to examine the lived experience of getting divorced in mid to later life. Data address the following research questions: 1) What are the divorcees’ expectations for the process of divorce and post-divorce life? 2) How do life phase factors and family relationships shape the divorce experience? Participants included 41 heterosexual men and women who legally divorced at the age of 55 or older and between 1-7 years from the time of the interview. Participants divorced from first and higher order marital unions. They included self-identified initiators, non-initiators, and co-initiators of the divorce. Results suggest that gray divorce is a complex experience marked by shifting feelings of ambivalence and certainty that are influenced by such factors as health and social networks, especially family.

Towards a complete classification of nonchiral topological phases in two-dimensional fermion systems

In recent years, fermionic topological phases of quantum matter has attracted a lot of attention. In a pioneer work by Gu, Wang, and Wen, the concept of equivalence classes of fermionic local unitary (FLU) transformations was proposed to systematically understand nonchiral topological phases in 2D fermion systems and an incomplete classification was obtained. On the other hand, the physical picture of fermion condensation and its corresponding super pivotal categories give rise to a generic mathematical framework to describe fermionic topological phases of quantum matter. In particular, it has been pointed out that in certain fermionic topological phases, there exists the so-called q-type anyon excitations, which have no analogues in bosonic theories. In this paper, we generalize the Gu, Wang, and Wen construction to include those fermionic topological phases with q-type anyon excitations. We argue that all nonchiral fermionic topological phases in $2+1\mathrm{D}$ are characterized by a set of tensors $({N}_{k}^{ij},{F}_{k}^{ij},{F}_{kln,\ensuremath{\chi}\ensuremath{\delta}}^{ijm,\ensuremath{\alpha}\ensuremath{\beta}},{n}_{i},{d}_{i})$, which satisfy a set of nonlinear algebraic equations parameterized by phase factors ${\mathrm{\ensuremath{\Xi}}}_{kl}^{ijm,\ensuremath{\alpha}\ensuremath{\beta}}$ and ${\mathrm{\ensuremath{\Xi}}}_{kln,\ensuremath{\chi}\ensuremath{\delta}}^{ij}$. Moreover, consistency conditions among algebraic equations give rise to additional constraints on these phase factors, which allow us to construct a topological invariant partition for an arbitrary triangulation of 3D spin manifold. Finally, several examples with q-type anyon excitations are discussed, including the fermionic topological phase from Tambara-Yamagami category for ${\mathbb{Z}}_{2N}$, which can be regarded as the ${\mathbb{Z}}_{2N}$ parafermion generalization of Ising fermionic topological phase.

A quantum walks assisted algorithm for peptide and protein folding prediction

Proteins are considered as the working force of cells. Their functionality is determined by their spatial form. In 1973 Anfinsen proposed that the spatial form is determined by the sequence of amino acids in the protein backbone. Yet, the number of possible sequences as well as the possible configurations is very large, making the task of predicting the protein's spatial form very difficult. Many approaches have been proposed, both classical and hybrid quantum – classical ones. We propose a novel hybrid algorithm. In our approach we utilized quantum walks, a proven model for universal quantum computation. We considered a simplified version of the protein backbone to be the evolution space of the quantum walk. The dihedral angles φ and ψ are introduced as phase factors to the quantum walk evolution. We also utilized a cost function to describe the system, where the R – chain, describing the specific amino acid, corresponds to a discrete value, affecting the cost functions value. Our aim is to minimize the cost function value, by updating the dihedral angles for specific regions of the Ramachandran plot, using a Metropolis algorithm.

Assessment of early wound healing, pain intensity, quality of life and related influencing factors during periodontal surgery: a cross-sectional study

This cross-sectional study assessed early wound healing, pain intensity, quality of life, surgical satisfaction, and related factors during periodontal surgery. A total of 369 patients completed the questionnaire before undergoing periodontal surgery (baseline), immediately after the operation (phase I), on the day of suture removal (phase II), and one month later (phase III). The Early Wound Healing Score (EHS) was assessed, and the short-form McGill Pain Questionnaire (SF-MPQ), tooth hypersensitivity visual analog scale (VAS), oral health-related quality of life measure (OHQoL-UK), and surgical satisfaction VAS were administered and analysed. The EHS was 8.41 ± 2.74 and was influenced by disease severity and surgical factors. Scores on the SF-MPQ, pain intensity scores, and OHQoL-UK scores were significantly increased in phase I and decreased later. Tooth sensitivity decreased significantly one month after periodontal surgery. Psychological factors were positively related to SF-MPQ, pain intensity, OHQoL-UK and tooth sensitivity VAS scores in all phases, while disease severity and surgical factors were only related to these scores at baseline or in phases I/II/III. Surgical acceptance and reoperation willingness continuously decreased after surgery, and all these scores were related to surgical satisfaction. EHS, pain intensity and quality of life were closely related to disease severity, psychological factors and surgical factors in phase I (i.e., immediately after surgery). The findings suggest that surgical details should be enhanced and that behavioural and psychological interventions measures should be implemented to improve outcomes during periodontal operation and during the early postoperative period as well as to improve patient-oriented periodontal surgery experiences. Trial registration This cross-sectional study did not include interventions with human participants, and all the experimental procedures involving humans in this study were approved by the Ethics Committee of West China College of Stomatology, Sichuan University (WCHSIRB-D-2020-284).

Generation of phase-only holograms with high-diffraction-order reconstruction by a U-Net-based neural network: A phase grating perspective

Implicit periodic structure in phase-only holograms will result in many diffraction orders in the diffraction field. We analyzed the diffraction pattern from a phase gratings point of view and proved that the diffraction orders were jointly influenced by the phase factor, the single-beam diffraction factor, and the multibeam interference factor. According to the analysis, we proposed the high-diffraction-order angular spectrum method (HDO-ASM) for the numerical reconstruction of high diffraction orders. Different from the conventional methods of removing high diffraction orders, we chose to reconstruct target images in high diffraction orders with HDO-ASM and a U-Net-based neural network. Finally, the 4 K phase-only holograms with high-diffraction-order reconstruction were generated in 0.09s and had a mean reconstruction quality of 34.3 dB (PSNR) in the DIV2K valid dataset. Theoretical and experimental results demonstrated that there are few speckle noises and fringes in the reconstructed images of holograms generated by the proposed method.

Tablet-Based Cognitive Stimulation in Parkinson's Disease: What Really Happens?

<h3>Research Objectives</h3> 1) To determine whether a remote tablet-based cognitive intervention program can improve measures of cognition for individuals with Parkinson's Disease (PD). 2) To examine the effects of remote coaching-style support on measures of cognition and adherence. <h3>Design</h3> Dual series of two 4-week tablet-based cognitive intervention in a within-subjects pre-post ABAC/ACAB design (counterbalanced) to assess changes in cognition and adherence in each phase (tablet activity with or without 3x/week meetings) with 2-week hiatus between phases. <h3>Setting</h3> General community. <h3>Participants</h3> Target n=12 (n=5 currently). Inclusion: Age 50+, proficiency in English, diagnosis of PD, no other neurological history, vison/hearing corrected to functional, and upper extremity function for tablet use. Exclusions: premorbid cognitive impairment, severe hearing, visual, or upper extremity impairment, concurrent speech therapy. <h3>Interventions</h3> Baseline & Post Testing (A): demographics, Unified Parkinson's Disease Rating Scale (UPDRS), subtests of Woodcock Johnson Test of Oral Language (WCJTOL) for cognition. Independent (B): Participants complete cognitive activities (e.g. n-back, pattern replication) using a tablet application using loaned iPads (4 weeks). Supported (C): Participants complete the identical protocol of Phase B with additional verbal feedback via 10-minute video conference 3x/week (4 weeks). <h3>Main Outcome Measures</h3> Repeated measures analysis of variance with within-subjects factor of intervention phase (B or C) will be used to determine differences in cognitive measures (UPDRS, WCJTOL). Comparative changes in adherence during interventions will also be examined. <h3>Results</h3> Preliminary findings (n=7) for independent tablet activity demonstrate varying adherence (MEAN=18.85/28 days; RANGE 13:26). Participants improved or maintained scores on UPDRS. Average score change in WCJTOL Rapid Picture Naming was 6.6 items (RANGE 4:13); Sentence Repetition average change was 1.16 items (RANGE 1:5). Full analysis will be completed upon full data collection in Summer 2022. <h3>Conclusions</h3> This clinically relevant work aims to determine practical approaches for effective stimulation in the face of service limits. Findings will reveal feasibility and effectiveness of such interventions for people with PD. <h3>Author(s) Disclosures</h3> Funding for this work is through an internal grant by the University Research Council at Seton Hall University. No other relevant disclosures.

Risk factor analysis on perioperative greater trochanteric fracture of total hip arthroplasty via anterolateral approach.

A greater trochanteric fracture is a perioperative complication of primary total hip arthroplasty (THA) via an anterolateral approach. Although surgeons determine risk factors in the preoperative planning phase, no study explored the relationship between the planned femoral implant and greater trochanter. This study attempts to determine the risk factors for perioperative greater trochanteric fractures in primary THA via an anterolateral approach. This retrospective single-institution study enrolled 440 patients (66 males and 374 females) who underwent primary THA via an anterolateral approach with a minimum follow-up of six months. First, we selected patients with perioperative greater trochanteric fractures, regardless of the need for additional surgery. Second, we investigated the risk factors for perioperative greater trochanteric fractures using the patients' demographic data, operative data, and femoral geometry data via univariate and multivariate analyses. Perioperative greater trochanteric fractures occurred in 30 joints (30/440, 6.8%), and all cases were reported in women. Multivariate analysis revealed that in cases where the top of the great trochanter was inside the longitudinal central axis of the planned femoral stem in three-dimensional templating (Type B) was the only independent risk factor for perioperative greater trochanteric fracture (odds ratio, 14.6; 95% confidence interval, 5.88-36.1; P < 0.001). This study identified female sex and Type B femoral geometry as risk factors for perioperative greater trochanteric fracture via an anterolateral approach. Our results may reduce the incidence of perioperative greater trochanteric fractures associated with primary THA.

Enhancement of Optomechanical Squeezing of Light Using the Optical Coherent Feedback.

A coherent feedback scheme is used to enhance the degree of squeezing of the output field in a cavity optomechanical system. In the feedback loop, a beam splitter (BS) plays the roles of both a feedback controller and an input-output port. To realize effective enhancement, the output quadrature should take the same form as the input quadrature, and the system should operate at the deamplification situation in the meantime. This can be realized by choosing an appropriate frequency-dependent phase angle for the generalized quadrature. Additionally, both the transmissivity of the BS and the phase factor induced by time delays in the loop affect optical squeezing. For the fixed frequency, the optimal values of transmissivity and phase factor can be used to achieve the enhanced optical squeezing. The effect of optical losses on squeezing is also discussed. Optical squeezing is degraded by the introduced vacuum noise owing to the inefficient transmission in the loop. We show that the enhancement of squeezing is achievable with the parameters of the current experiments.

Hierarchically structured powder metallurgy austenitic stainless steel with exceptional strength and ductility

Powder metallurgy stainless steels have attracted much attention due to their wide applications. However, they often exhibit a low relative density (<96%) and a strength-ductility trade-off dilemma. We herein study the microstructure and mechanical property of a dense hierarchically structured stainless steel, which is synthesized by a high-pressure (4 GPa)/high-temperature (1200 °C) sintering technique and exhibits a relative density of approx. 99%. The hierarchically structured stainless steel is composed of 27.5% microcrystalline phase with an average grain size of 9 μm and 72.5% ultrafine-grained phase with an average grain size of 259 nm. These unique microstructures together with the high relative density enable us to achieve an exceptional combination of high yield strength of 1188 ± 59 MPa and a relatively high tensile elongation of 15 ± 2.6%, evading the strength-ductility dilemma observed in conventional powder metallurgy stainless steels synthesized by pressureless or low-pressure sintering. The high strength is mainly caused by the ultrafine-grained phase, which can be obtained even after sintering nanocrystalline stainless steel powders at a high temperature of 1200 °C (∼87% of melting temperature). The ultrafine-grained phase and the grain boundary strengthening factor in the ultrafine-grained phase contributes 91% and 48% to the total strength, respectively. Both experiments and calculations indicate that increasing the sintering pressure from 40 MPa to 4 GPa can significantly lower the grain growth rate by approx. 64%. The high ductility is mainly caused by the microcrystalline phase, which causes the formation of a large number of dislocations and the generation of nano-twins.