Simple Field Research Articles

Assessment of the cardiorespiratory fitness and the quality of life of patients with breast cancer undergoing chemotherapy: a prospective study.

Diminished cardiorespiratory fitness is a well-known side effect of chemotherapy as well as a risk factor for potential cardiovascular diseases among cancer patients. This study aimed to assess the potential effects of systemic adjuvant (ACT) or neoadjuvant (NACT) chemotherapy on cardiorespiratory fitness and quality of life (QoL) among breast cancer (BC) patients. Demographic data, cardiorespiratory fitness, health-related QoL domains were assessed with simple data form, six-minute walk test (6MWT), European Organization for Research and Treatment of Cancer quality of life module (EORTC-C30), and Functional Assessment of Cancer Therapy (FACT-B+), respectively. Time1 (T1, prior to chemotherapy), Time2 (T2; interim assessment), and Time3 (T3, final assessment) were set as assessment points. A total of 42 patients (32 ACT vs 10 ACT) completed all assessments. There were no significant differences of main effect of time and time*group interaction on total walked distance (TWD) after controlling for age and BMI (F(2,28) = 1.309, p = 0.286; F(2,28) = 1.444, p = 0.253). EORTC symptoms subscale was found to be correlated with EORTC and FACT-B+ physical function (PF) subscales (r = -861, p < 0.001; r = -0.877, p < 0.001) in T3. The EORTC PF subscale was found to be correlated with the TWD in the baseline (r = 0.411, p = 0.024). This study showed that the effect of chemotherapy on diminished PF and remarkably increased symptom burden among BC patients. Yet, the type of chemotherapy had no effect on TWD regarding cardiorespiratory fitness. Monitoring potential functional decline regarding cardiorespiratory fitness can be performed via simple field tests such as 6MWT.

Holographic open quantum systems: toy models and analytic properties of thermal correlators

We present a unified picture of open quantum systems, the theory of a system probing a noisy thermal environment, distilling lessons learnt from previous holographic analyses. Our treatment is applicable both when the system is coupled to short-lived (Markovian), and long-lived (non-Markovian) environmental degrees of freedom. The thermal environment is modeled using an asymptotically AdS black hole, and the systems of interest are simple probe field theories. The effective stochastic dynamics of the system is governed by real-time thermal correlators, which we compute using the gravitational Schwinger-Keldysh (grSK) geometry. We describe the structure of arbitrary tree-level contact and exchange Witten diagrams in the grSK geometry. In particular, we argue, that all such diagrams reduce to integrals supported on a single copy of the exterior of the black hole. The integrand is obtained as a multiple discontinuity of a function comprising ingoing boundary-bulk propagators, monodromy functions which appear as radial Boltzmann weights, and vertex factors. These results allow us to deduce the analytic structure of real-time thermal n-point functions in holographic CFTs. We illustrate the general statements by a two-dimensional toy model, dual to fields in the BTZ background, which we argue captures many of the essential features of generic open holographic QFTs.

Quantum critical dynamics in the two-dimensional transverse Ising model

In the vicinity of the quantum critical point (QCP), thermodynamic properties diverge toward zero temperature governed by universal exponents. Although this fact is well known, how it is reflected in quantum dynamics has not been addressed. The QCP of the transverse Ising model on a triangular lattice is an ideal platform to test the issue, since it has an experimental realization, the dielectrics being realized in an organic dimer Mott insulator, $\ensuremath{\kappa}\text{\ensuremath{-}}{\mathrm{ET}}_{2}X$, where a quantum electric dipole represents the Ising degrees of freedom. We track the Glauber-type dynamics of the model by constructing a kinetic protocol based on the quantum Monte Carlo method. The dynamical susceptibility takes the form of the Debye function and shows a significant peak narrowing in approaching a QCP due to the divergence of the relaxation timescale. It explains the anomaly of dielectric constants observed in the organic materials, indicating that the material is very near the ferroelectric QCP. We disclose how the dynamical and other critical exponents develop near QCP beyond the simple field theory.

Covariant Wick rotation: action, entropy, and holonomies

Given an arbitrary Lorentzian metric g_{ab} and a nowhere vanishing, timelike vector field u^a, one can construct a class of metrics {widehat{g}}_{ab} which have Euclidean signature in a specific domain, with a transition to Lorentzian regime occurring on some hypersurface Sigma orthogonal to u^a. Geometry associated with {{{widehat{g}}}}_{ab} has been shown to yield some remarkable insights for classical and quantum gravity. In this work, we focus on studying the implications of this geometry for thermal effects in curved spacetimes and compare and contrast the results with those obtained through conventional Euclidean methods. We show that the expression for entropy computed using {widehat{g}}_{ab} for simple field theories and Lanczos–Lovelock actions differ from Wald entropy by additional terms depending on extrinsic curvature. We also compute the holonomy associated with loops lying partially or wholly in the Euclidean regime in terms of extrinsic curvature and acceleration and compare it with the well-known expression for temperature.

Symmetry phases of asymmetric simple exclusion processes on two lanes with an intersection

This paper studies two-lane asymmetric simple exclusion processes (ASEPs) with an intersection. In the upstream segments of the intersection, one particle can move to the next site with rate 1 if the site is empty, and the other particle can move forward with rate p in the sites of downstream segments. The parameter p can represent the rate of slowing of motion, and the parameter is introduced to investigate spontaneous symmetry breaking (SSB) phenomenon. Extensive Monte Carlo simulations are carried out. It is shown that three symmetric phases exist and the SSB does not exist in the system. Simple mean field approach in which correlation of sites is ignored is firstly adopted to analyze the system, and the system is divided into four independent segments. It is found that the analytical results deviate from the simulation ones, especially when p is small. In addition, the inexsitence of SSB can only be explained qualitatively. Motivated by this, we carry out the cluster mean field analysis in which correlation of five sites is considered. It is shown that densities of the two upstream segments are equal, which demonstrates that the SSB does not exist. It is also shown that, as expected, the cluster mean field analysis performs much better than the simple mean field analysis.

Light transport through a magneto-optical medium: simple theory revealing fruitful phenomena.

Electromagnetic wave transmission in a magneto-optical (MO) medium is a basic and old topic but has raised new interest in recent years, because MO medium plays a vital role in optical isolator, topological optics, electromagnetic field regulation, microwave engineering, and many other technological applications. Here, we describe several fascinating physical images and classical physical variables in MO medium by using a simple and rigorous electromagnetic field solution approach. We can easily obtain explicit formulations for all relevant physical quantities, such as the electromagnetic field distribution, energy flux, reflection/transmission phase, reflection/transmission coefficients, and Goos-Hänchen (GH) shift in MO medium. This theory can help to deepen and broaden our physical understanding of basic electromagnetics, optics, and electrodynamics in application to gyromagnetic and MO homogeneous medium and microstructures, and might help to disclose and develop new ways and routes to high technologies in optics and microwave.

A single-step plasma method for rapid production of 2D, ferromagnetic, surface vacancy-engineered MoO3−x nanomaterials, for photothermal ablation of cancer

A rapid, clean plasma-chemical technique is demonstrated here, for cost-effective, synthesis of surface vacancy engineered, 2D, molybdenum-oxide nanomaterials, during a one-step, integrated synthesis-hydrogenation process for biomedical applications. A laminar plasma beam populated with O and H radicals impinges on a molybdenum target, out of which molybdenum-oxide nanomaterials are very rapidly generated with controlled surface O vacancies. 2D, dark-blue coloured, nano-flake/ribbon like MoO3−x is produced maximum up to 194 g h−1, the core of which still remains as stoichiometric molybdenum-oxide. These nanomaterials can get heated-up by absorbing energy from a near-infrared (NIR) laser, which enable them as photothermal therapy (PTT) candidate material for the invasive precision therapy of cancer. The surface defects endows the products with robust ferromagnetism at room temperature conditions (maximum saturation-magnetization: 6.58 emu g−1), which is order of magnitude stronger than most other vacancy engineered nanomaterials. These nanometric metal-oxides are observed to be perfectly compatible in animal physiological environment and easily dispersed in an aqueous solution even without any pre-treatment. The MoO3−x nanomaterials are stable against further oxidation even under prolonged atmospheric exposure. In vitro experiments confirm that they have ideal efficacy for photothermal ablation of human and murine melanoma cancer at relatively lower dose. During in vivo PTT treatments, they may be manipulated with a simple external magnetic field for targeted delivery at the malignant tumours. It is demonstrated that commensurate to the neutralization of the malignant cells, the nanomaterials themselves get self-degraded, which should get easily excreted out of the body.

Experimental Study of the Formation and Evolution of Gas Jets in Supersonic Combustion Chambers

A simple and efficient flow field visualization method (based on shadow imaging) was applied in a direct-connect test to explore the influence of the momentum flux ratio and the jet angle on the formation and evolution of nitrogen jets in supersonic combustion chambers. The test setup adopts a rectangular flow passage to simulate a flight condition with Mach number of 6 and altitude of 25 km. The experimental results showed that (a) the flow field visualization method adopted in this paper can clearly register the formation and evolution of the shock wave structure in the flow field and the windward shear vortex on the jet surface. (b) The evolution process of the windward shear vortex is significantly affected by the jet angle. In particular, the stretching position of the windward shear vortex changed when the jet angle was obtuse. (c) The bow shocks showed local distortion due to the periodic generation of large-scale shear vortexes. (d) Under the working conditions of the test, the largest instability of the flow field was found for a jet angle of 120°. This work provides, on one hand, the experimental basis for clarifying the formation and evolution mechanism of transverse gas jets, and on the other, valuable data that can be used to validate numerical simulations.

Fundamentals of Rhenium-188 Radiopharmaceutical Chemistry.

The β- emitter, rhenium-188 (188Re), has long been recognized as an attractive candidate for targeted cancer radionuclide therapy (TRNT). This transition metal shares chemical similarities with its congener element technetium, whose nuclear isomer technetium-99m (99mTc) is the current workhorse of diagnostic nuclear medicine. The differences between these two elements have a significant impact on the radiolabelling methods and should always receive critical attention. This review aims to highlight what needs to be considered to design a successful radiopharmaceutical incorporating 118Re. Some of the most effective strategies for preparing therapeutic radiopharmaceuticals with 188Re are illustrated and rationalized using the concept of the inorganic functional group (core) and a simple ligand field theoretical model combined with a qualitative definition of frontiers orbitals. Of special interest are the Re(V) oxo and Re(V) nitrido functional groups. Suitable ligands for binding to these cores are discussed, successful clinical applications are summarized, and a prediction of viable future applications is presented. Rhenium-188 decays through the emission of a high energy beta particle (2.12 MeV max energy) and a half-life of 16.9 h. An ideal biological target would therefore be a high-capacity target site (transporters, potential gradients, tumour microenvironment) with less emphasis on saturable targets such as overexpressed receptors on smaller metastases.

Psychoacoustic Analysis of Various Train Pass-by Noise Using

Due to the recent high speed of railway, noise and vibration generated during operation has emerged as a major social problem. Specially, the internal noise of railway varies depending on various operating conditions such as speed, vehicle crossings, and tunnel entry, and has a great effect on the riding comfort of passengers. In this study, an evaluation method for binaural noise of train pass-by noise and a simple wave field model which can reflect the Doppler effect are examined. To reflect the binaural characteristics of train pass-by noise, binaural measurements were conducted for several types of train, different measurement distances and various measurement angles. The annoyances of measured binaural noises were analyzed using conventional sound pressure level, psychoacoustic metrics, and their rate of change. Also, the noise emitted from high-speed railways was measured and characterized. By its analysis result, moving sounds were synthesized considering an initial frequency and a frequency shift. The synthesized sounds were convolved to reflect binaural condition. Auditory experiments were conducted using the synthesized moving sound stimuli, and the effects of the Doppler frequency shift on annoyance of moving sound sources were obtained.

Relativistic force-free models of the thermal X-ray emission in millisecond pulsars observed by NICER

ABSTRACTJPSeveral important properties of rotation-powered millisecond pulsars (MSPs), such as their mass-radius ratio, equation of state and magnetic field topology, can be inferred from precise observations and modelling of their X-ray light curves. In the present study, we model the thermal X-ray signals originated in MSPs, all the way from numerically solving the surrounding magnetospheres up to the ray tracing of the emitted photons and the final computation of their light curves and spectra. The magnetosphere is solved by performing general relativistic force-free simulations of a rotating neutron star (NS) endowed with a simple centred dipolar magnetic field, for many different stellar compactness and pulsar misalignments. From these solutions, we derive an emissivity map over the surface of the star, based on the electric currents in the magnetosphere. In particular, the emission regions (ERs) are determined in this model by spacelike four-currents that reach the NS. We show that this assumption, together with the inclusion of the gravitational curvature on the force-free simulations, lead to non-standard ERs facing the closed-zone of the pulsar, in addition to other ERs within the polar caps. The combined X-ray signals from these two kinds of ERs (both antipodal) allow to approximate the non-trivial interpulses found in several MSPs light curves. Our modelled X-ray signals are compared against very accurate NICER observations of four target pulsars: PSR J043-4715, PSR J1231-1411, PSR J2124-3358, and PSR J0030 + 0451; achieving very good simultaneous fits for their light curves and spectral distributions.

Modular Electromagnetic Transducer for Optimized Energy Transfer via Electric and/or Magnetic Fields.

In this paper, a modular electromagnetic transducer that achieves the optimal transfer of energy from the electric and/or magnetic fields is proposed. Both the magnetic field resonance coupling and the influence of the electric field near the copper transducers of the printed circuit board and inside the FR4-type epoxy material are considered. In our printed arrays of flat transducers, we consider face-to-face capacitances for the study of resonance coupling. Because the space between coil turns is almost double the plate thickness, the coplanar capacitance can be ignored for frequencies under 2 MHz. A radio frequency (RF) transmitter and transducer were built to demonstrate the increased energy transfer efficiency when using both electric and magnetic fields in the near-field region. The transversal leakage flux coupling of a long RF coil was more efficient than a simple axial magnetic field coupling when using pancake transceiver coils. The optimal configuration having one long coil at the base and two or more flat coils as capacitor plates near coil ends generated the highest tandem of magnetic and electrical fields. A power regression tool was used to convert and simplify the transducer current and voltage variation with distance. In this regard, the current change corresponded to magnetic field variation and the voltage change to the electric field variation. New formulas for estimating the near-field region and the self-capacitance of the RF transformer coil are proposed; the optimal function in the frequency domain for a given transducer distance was defined by simulation.

Load transfer analysis of vertically loaded bored piles in sea reclamation areas considering the effect of the pile-gravel interface roughness

A load transfer model for vertically loaded bored piles in sea reclamation areas with gravel is proposed in this paper. The focus is on quantifying the mobilization of pile-side friction, which is closely related to the shear behaviors of the pile-gravel interface. The surface profile of the gravel particles and the concrete piles are assumed to be circle and wave curves, respectively. The shear displacement and dilatancy calculation are based on the macro and micro geometry relationship between gravel particles and pile surface. The shear stress calculation of the pile-gravel interface is dealt with by empirical elastoplastic equations. A simple slip-line field is also built to identify the critical shear displacement. The finite difference equations are used to derive the load-displacement curves for vertically loaded bored piles in sea reclamation areas with gravel. The model predictions are compared with field observations and particle flow numerical simulation to validate the performance of the proposed method, and the results prove to be reasonable. Moreover, parameter studies are conducted and the results prove that the pile can bear more load when the particle diameter is similar to the pile's rough surface, and both the increases of wave angle and the relative friction coefficient can promote the bearing capacity.

Magnetic Fe3O4/MIL-101 composite as a robust adsorbent for removal of p-arsanilic acid and roxarsenic in the aqueous solution

The p-arsanilic acid (p-ASA) and roxarsenic (ROX) are typical organic arsenic compounds (OACs), which can be evolved into highly poisonous inorganic arsenic species in the aqueous solution. Herein, a magnetic MOFs-based composite of Fe3O4/MIL-101 was successfully obtained by a stepwise solvothermal method and further used in the adsorption of p-ASA and ROX. The structural and physicochemical characteristics of Fe3O4/MIL-101 were firstly investigated in detail. It was found that Fe3O4 microspheres were evenly embedded on the polyhedral MIL-101 surface after the solvothermal process and exhibited a strong superparamagnetic property. After adsorption, a simple external magnetic field can be used to quickly separate the composite from the aqueous solution. The adsorption experiments indicated that the composite is an excellent adsorbent with maximum adsorption capacities of 683.44 and 946.57 mg·g−1 for p-ASA and ROX, respectively. In addition, the effects of composite dosage, initial pH and co-existing anions on the adsorption efficiency were investigated. The main adsorption mechanism consists of the existence of hydrogen bonding, π-π stacking and As-O-Fe coordination between Fe3O4/MIL-101 composite and OACs. We believe that this study would be very meaningful to promote the application of magnetic MOFs based composites for effective adsorption for OACs in the environmental remediation.

A novel scheme for error field correction in permanent magnet stellarators

Stellarators offer a promising path towards fusion reactors, but their design and construction are complicated by stringent tolerance requirements on highly complex 3D coils. A potential way to simplify the engineering requirements for stellarators is to use simple planar toroidal field coils along with permanent magnet arrays to generate shaping fields. In order to ensure sufficient field accuracy while minimizing engineering complexity and system cost, new techniques are required to correct the field produced by the permanent magnet arrays to within requirements set by plasma physics. This work describes a novel correction method developed for this purpose. This analysis is applied to the design of a quasi-axisymmetric stellarator that employs a combination of permanent magnets and planar toroidal field coils to generate its magnetic field. Analysis techniques and initial results using the method for error correction on a proposed permanent magnet stellarator are shown, and it is demonstrated that the method successfully meets the design requirements of the project.

Evaluation of genetic diversity and production adaptability in different germplasms of Paspalum dilatatum

AbstractPaspalum dilatatum is an excellent warm‐season forage grass and soil conservation plant in subtropical regions. However, information on P. dilatatum cultivation in southwestern China is limited. A preliminary evaluation of the genetic diversity and adaptability of six P. dilatatum germplasms was conducted in Guizhou based on inter simple sequence repeat (ISSR) markers and field trials. Fifteen polymorphic primers were screened from 50 ISSR primers. A total of 141 bands were generated, 124 of which were polymorphic, yielding 88.63% polymorphic bands. The number of polymorphic loci detected for the different germplasms ranged from 23 to 61, and the percentage of polymorphic loci was 40.67%. The mean number of alleles was 1.23, and the effective allele number was 1.15. Nei's genetic diversity index was 0.08. The Shannon information index was 0.12, and the genetic similarity coefficient (GSC) ranged from 0.6002 to 0.8955, indicating a relatively rich genetic base among the germplasms. The unweighted pair group method with arithmetic mean approach was used to construct the clustering map. Using a GSC of 0.83 as the threshold value, the six germplasm materials were divided into four clusters, indicating that ISSR molecular markers can be effectively applied to analyze the genetic diversity of P. dilatatum germplasms. Cluster analysis of 12 growth characteristics of the germplasms of P. dilatatum showed that germplasm 4 exhibited strong tillering ability and a high crude protein content. Germplasm 3 showed high plant height, fresh yield and hay yield. Germplasm 1 showed the lowest forage yield and crude protein content. Germplasms 2, 5 and 6 showed excellent crude protein and crude fat contents; the remaining indicators showed intermediate performance. This study provides important references for the utilization and variety selection of introduced P. dilatatum resources in the karst areas of Guizhou.

Comparing two methods to perform a beerkan infiltration run in a loam soil at different dates

Performing beerkan infiltration runs with different heights of water pouring could help to obtain saturated soil sorptivity, S, and hydraulic conductivity, Ks, data usable to explain and simulate hydrological processes. However, most of the available information on the L (low height of water pouring, nearly 3 cm) – H (high height, 1–2 m) methodology refers to runs making use of a relatively limited number of water volumes and there is some sign that a few water volumes could yield an incomplete description of soil alteration phenomena induced by wetting. For a loam soil, the objective of this investigation was to determine water pouring height effects on the S and Ks values obtained in different sampling dates with more than usual amounts of applied water. Soil alteration due to the mechanical impact of the applied water appeared almost completed by the end of the runs in all cases but in a more advanced stage when the soil was initially more sorptive and conductive. Overall, the H runs yielded 2.3–2.8 times smaller S values and 8.5–14.5 times smaller Ks values than the L runs but differences between the L and H methodologies varied during the sampling period. In particular, these differences were smallest when the soil was initially relatively wet and little sorptive and conductive (S and Ks values differing with the experiment by no more than two times) and largest in the opposite conditions (S and Ks values differing by 3 and 17–21 times, respectively). The L runs yielded coefficients of variations, CV, of 14–60 % for S and 45–171 % for Ks, depending on the sampling date, and a ratio between the highest and the lowest mean of 2.5 for S and 11.8 for Ks. With the H runs, the corresponding CV values were 14–38 % for S and 35–107 % for Ks and two means differed at the most by 1.3 times for S and 2.2 times for Ks. Therefore, the H runs described a soil that was less sorptive, less conductive, more spatially homogeneous and more temporally stable than the L runs. Less runs could be enough to parameterize the soil in a disturbed condition as compared with the undisturbed one. Further testing the L-H methodology in other environmental conditions is recommended in the perspective to develop simple field methods to determine the hydrodynamic properties of both a nearly undisturbed soil and an intensively disturbed soil.

Phantom Car Attack Detection via Passive Opportunistic RF Localization

A novel opportunistic approach of passive RF localization is presented for detecting “phantom car” attacks, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">i.e</i> ., vehicles intentionally reporting false position/velocity information to surrounding vehicles and communication networks. Current state-of-the-art approaches for vehicle localization mostly rely on either: (i) self-reported position/velocity updates obtained via navigation technologies such as GPS, or (ii) cooperative communication approaches involving multiple vehicles exchanging situational awareness information with each other. In both cases, these approaches assume that all vehicles involved truthfully share their actual location information, which might not be the case if malicious users are present within the traffic flow. The proposed approach does not make this assumption. Rather, it extracts location information of vehicles operating on the road without the need to cooperate with them. Multiple sensors surrounding these vehicles are opportunistically and passively measured for their RF emission characteristics ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">e.g</i> ., received signal strength, time difference of arrival) based on using on-board widely available wireless signals ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">e.g</i> ., 5G, Bluetooth, WiFi). These RF emissions are not intentionally designed to be used in localization applications. Their characteristics are processed via data fusion and bounded via vehicle dynamics behavioral models before being compared against reported positions within the vehicular communications network. This paper presents the phantom car attack model used in this work to compromise conventional vehicle localization techniques, as well as the framework and its respective sub-components implementing the proposed detection approach. To evaluate the feasibility of the proposed approach, a custom-built Python-based computer simulation platform is described that accurately models the vehicular environment and its associated RF emissions characteristics. Finally, a simple hardware field experiment evaluating the performance of the proposed approach incorporating RF localization, data fusion, and vehicle behavioral dynamics modules illustrates the viability of identifying phantom car attacks within a non-cooperative framework.

A Study on the Initiation of Discontinuities in Hypoplastic Granular Materials for Some Simple Motion Fields in Classical Continua

A Study on the Initiation of Discontinuities in Hypoplastic Granular Materials for Some Simple Motion Fields in Classical Continua

Optimal Path Generation with Obstacle Avoidance and Subfield Connection for an Autonomous Tractor

As autonomous tractors become more common crop harvesting applications, the need to optimize the global servicing path becomes crucial for maximizing efficiency and crop yield. In recent years, several methods of path generation have been researched, but very few have studied their applications on complex field shapes. In this study, a method of creating the optimal servicing path for simple and complex field shapes is proposed. The proposed algorithm creates subfields for a target land, optimizes the track direction for several subfields individually, merges subfields that result in overall increased efficiency, and finds the minimum non-operating paths to travel from subfield to subfield while selecting the respective optimal subfield starting locations. Additionally, it is required that this process must be done within 3 seconds to meet performance requirements. Results from 3 separate field shapes show that the field traversal efficiency can range from 68.0% to 94.4%, and the coverage ratio can range from 98.8% to 99.9% for several different conditions. In comparison with previous studies using the same field shape, the proposed methods demonstrate an increase of 5.5% in field traversal efficiency.