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Reliable and precise straightness profile measurements are crucial for manufacturing ultra-precision components and are capable of further enhancing their accuracy. The Fourier three-probe (F3P) straightness measurement allows for precise assessment of the workpiece profile on the machine by eliminating the harmful influence of the error motion of the sliding table. However, the probe spacing uncertainty deteriorates the measurement accuracy remarkably; and, the affecting mechanism behind this phenomenon has not yet been studied in detail. In this context, this paper thoroughly investigated the propagation of the probe spacing uncertainty in the F3P measurement. First, the influence of the probe spacing deviation is analyzed. Next, by calculating the partial differential of Laplace transform of the workpiece profile, we algebraically deduce the probe spacing uncertainty propagation law, especially in the harmonic domain. Subsequently, Monte Carlo simulations are carried out to confirm the derived propagation law. To reduce uncertainty propagation, a hybrid approach is presented: (I) F3P measurements are carried out under changing probe spacings to produce several sets of Fourier coefficients; (II) optimal harmonic estimates are selected individually according to the harmonic uncertainty. Finally, simulations and experimental measurements are performed for verification. • Spacing uncertainty propagation law in F3S straightness measurement is deduced. • Monte Carlo method is adopted to confirm the derived propagation law. • Hybridization in harmonic domain is proposed to reduce uncertainty propagation. • The hybrid method enables reduction of both random and systematic uncertainties. [ABSTRACT FROM AUTHOR]

Precise control at the colloidal scale is one of the most promising bottom-up approaches to fabricating new materials and devices with tunable and precisely engineered properties. Magnetically driven colloidal assembly offers great versatility because of the ability to externally tune particle-particle interactions and to construct a host of particle arrangements. However, despite previous efforts to probe the parameter space, global orientational control in conjunction with two-dimensional microstructural control has remained out of reach. Furthermore, the magnetic relaxation time of superparamagnetic beads has been largely overlooked despite being a key feature of the magnetic response. Here, we take advantage of the magnetic relaxation time of superparamagnetic beads in an alternating rotating magnetic field and show how harnessing this feature facilitates the formation of oriented clusters. The orientation of these clusters can be controlled by field parameters. Using experiments, simulations, and theory, we probe a two-particle system (dimer) under this alternating rotating magnetic field and use its dynamics to provide insights into the collective response that forms clusters. We find that the type of field has significant implications for the dipolar interactions between the colloids because of the nonnegligible magnetic relaxation. Moreover, we find that the competing time scales of the magnetic relaxation and the alternating field generate an anisotropic interaction potential that drives cluster alignment. By exploiting the magnetic relaxation time of magnetic systems, we can tailor new types of interparticle interactions, thereby expanding the capabilities of colloidal assembly in engineering unique materials and devices. [ABSTRACT FROM AUTHOR]

Components used for the structure of the GLObal SolarWind Structure experiment in the NASA Interstellar Mapping and Acceleration Probe space mission, made of AA6061-T6 alloy, are subjected to the coating process, where the temperature affects its mechanical properties. This paper aims to examine the impact of the coating thermal cycle on the mechanical properties of AA6061-T6 alloy, which is the load-carrying material in a spaceborne instrument. As a part of the manufacturing process, the parts made of AA6061-T6 are subjected to a coating process at a temperature of about 220°C for a time longer than 1 hour. This treatment modifies the mechanical properties of the alloy. To evaluate the consequences of this change for spaceborne components, mechanical testing, and numerical simulation were conducted. It was found that as a result of the coating process, the reduction in AA6061-T6 yield strength is about 16%, which entails a decrease in the margins of safety by 25% at its maximum. [ABSTRACT FROM AUTHOR]

The use of airships to launch space probes has been an effective means of conducting typhoon surveys in recent years, but the carrying area and weight of airships are very limited, so it is necessary to reduce the weight and volume of the release device as much as possible. This paper reports the first use of a probe with cylindrical and omnidirectional characteristics, as well as a four-arm spiral receiving antenna, which can also act as the downward release device of the inner wall and improve the space utilization rate. Through further analysis and improvement, it was determined that the four-armed helical antenna can be printed on the medium using a flexible material, which not only reduces the weight of the device but also avoids direct contact between the antenna and the sounding device and improves the stability of the antenna. The designed antenna was modeled and simulated using Ansys HFSS 2021 simulation software.The simulation results show that the antenna presented in this study achieves good performance at the center frequency of 403 MHz, the input voltage VSWR and return loss of the antenna are ideal, and the antenna has a good directional map. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) tissue-engineered scaffolds mimic the physiological environment of cells by providing essential structural support, biochemical cues, and the mechanical strength needed for cell adhesion, proliferation, migration, and differentiation. Hydrogels like polyethylene glycol diacrylate (PEGDA) are commonly used biomaterials for cell culture due to their affordability, tunable stiffness, and ability to efficiently transport nutrients and gases. However, PEGDA lacks cell adhesion sites essential for cell proliferation and migration and has limited degradability. Methacrylated gelatin (GelMA) produced from denatured bovine collagen, crosslinks under ultraviolet light (UV) resulting in a degradable hydrogel with cell adhesion sites. Here, we synthesized GelMA with variable degree of methacrylation and crosslinked it with PEGDA to produce cell scaffolds with independently tunable mechanical and biochemical properties by varying the ratios of the two polymers. We determined polymer ratios that resulted in scaffolds with different mechanical properties but the same gelatin concentrations (providing cell adhesion and degradation sites) as well as different gelatin concentrations but the same mechanical properties. With the developed scaffold library, we further used a design of experiments approach to probe the parameter space and perform detailed analysis on chemical compositionscaffold properties as well as scaffold properties-cell behavior correlations. Our findings showed that hydrogel properties such as modulus, swelling, pore size, and permeability, strongly depended on total polymer concentration and not on theGelMA fraction. GelMA significantly influenced cell spreading, while addition of any amount of PEGDA delayed cell spreading significantly. We suggest that such analysis will broaden the utility of the GelMA/PEGDA hydrogels, presenting a versatile platform for mechanosensing research in 3D environments. [ABSTRACT FROM AUTHOR]

Context. The MIRI instrument on board the James Webb Space Telescope probes the chemistry and dust mineralogy of the inner regions of protoplanetary disks. The observed spectra are unprecedented in their detail and reveal a rich chemistry with strong diversity between objects. This complicates interpretations that are mainly based on manual continuum subtraction and 0D slab models. Aims. We investigate the physical conditions under which the gas emits in protoplanetary disks. Based on MIRI spectra, we apply a full Bayesian analysis that provides the posterior distributions of dust and molecular properties, such as column densities and emission temperatures. Methods. To do so, we introduced the Dust Continuum Kit with Line emission from Gas (DuCKLinG), a Python-based model simultaneously describing the molecular line emission and the dust continuum of protoplanetary disks without large computational cost. The model describes the dust continuum emission by dust models with precomputed dust opacities. The molecular emission is based on LTE slab models but from extended radial ranges with gradients in column densities and emission temperatures. We compare the model to observations using Bayesian analysis with linear regression techniques to reduce the dimension of the parameter space. We benchmarked this model to a complex thermo-chemical ProDiMo model of AATau and fit the MIRI spectrum of GW Lup. The latter allowed for a comparison to the previous results obtained with single slab models and hand-fitted continuum. Results. We successfully decrease the computational time of the fitting method by a factor of 80 by eliminating linear parameters, such as the emission areas, from the Bayesian run. This approach does not significantly change the retrieved molecular parameters, and only the calculated errors on the optically thin dust masses slightly decrease. For an AA Tau ProDiMo mock observation, we find that the retrieved molecular conditions from DuCKLinG (column densities from 3 × 1018 cm−2 to 4 × 1020 cm−2, radial range from 0.2 au to 1.2 au, and temperature range from about 200 K to 400 K) fall within the true values from ProDiMo (column densities between 4 × 1017 cm-2 to 5 × 1020 cm−2, radial extent 0.1 au to 6.6 au, and temperature range from about 120 to 1000 K). The smaller DuCKLinG ranges can be explained by the relative flux contributions of the different parts of ProDiMo. The parameter posterior of GW Lup reinforces previously found results. The previously determined column densities fall within the retrieved ranges in this study for all examined molecules (CO2, H2O, HCN, and C2H2). Similar overlap is found for the temperatures with only the temperature range of HCN (from 570−60+60 to 750−70+90 K) not including the previously found value (875 K). This discrepancy may be due to the simultaneous fitting of all molecules compared to the step-by-step fitting of the previous study. There is statistically significant evidence for radial temperature and column density gradients for H2O and CO2 compared to the constant temperature and column density assumed in the 0D slab models. Additionally, HCN and C2H2 emit from a small region with near constant conditions. Due to the small selected wavelength range 13.6–16.3 µm, the dust properties are not well constrained for GW Lup. DuCKL inG can become an important tool to analyse the molecular emission and dust mineralogy of large samples based on JWST /MIRI spectra in an automated way. [ABSTRACT FROM AUTHOR]

Introduction: Pepper (Capsicum spp.) is a vegetable that is cultivated globally and has undergone extensive domestication, leading to a significant diversification in its agronomic traits. With the advancement of genomics in pepper and the reduction in sequencing costs, the high-throughput detection of single nucleotide polymorphisms (SNPs) and small insertions-deletions (indels) has become increasingly critical for analyzing pepper germplasms and improving breeding programs. As a result, there is a pressing need for a cost-effective, highthroughput, and versatile technique suitable for both foreground and background selection in pepper breeding. Methods: In the present study, Python-based web scraping scripts were utilized to systematically extract data from published literatures and relevant sequence databases focusing on pepper genomes. Subsequent to data extraction, SNPs and indels were meticulously identified and filtered. This process culminated in the delineation of core polymorphic sites, which were instrumental in the development of specific probes. Following this, comprehensive phenotypic and genotypic analyses were conducted on a diverse collection of 420 pepper germplasms. Concurrently, a genome-wide association study (GWAS) was conducted to elucidate the genetic determinants of helical fruit shape in peppers. Results: In this study, a 45K pepper Genotyping-By-Target-Sequencing (GBTS) liquid-phase gene chip was developed on the GenoBaits platform. This chip is composed of 45,389 probes, of which 42,535 are derived from core polymorphic sites (CPS) in the background genetic landscape, while 2,854 are associated with foreground agronomic traits, spanning across 43 traits. The CPS probes are spaced at an average interval of 68 Kb. We have assessed the performance of this chip on 420 pepper germplasms, with successful capture of target DNA fragments by 45,387 probes. Furthermore, the probe capture ratio surpassed 70% in 410 of the 420 germplasms tested. Using this chip, we have efficiently genotyped 273 germplasms for spiciness levels and elucidated the genetic relationships among 410 pepper germplasms. Our results allowed for precise clustering of sister lines and C. chinense germplasms. In addition, through a GWAS for helical fruit shape, we identified three quantitative trait loci (QTLs): heli2.1, heli11.1, and heli11.2. Within the heli11.1 QTL, a gene encoding the tubulin alpha chain was identified, suggesting its potential role in the helical growth pattern of pepper fruits. [ABSTRACT FROM AUTHOR]

The possibility of setting up a space experiment aimed at detecting ultra-small deviations of the law of gravity of the central star of the planetary system from the Newton and Schwarzschild formats is demonstrated. The experiment comprises a ballistic flight of a space-probe along a trajectory composed of three treks divided by two gravity assist (GA) maneuvers at different planets, each GA acting as a powerful amplifier of the probe deflections caused by small deviations of the gravitational law. It is shown that the proposed (different) analytical and numerical computations of the probe's flight in a model of a planetary system simulating the Sun, Earth, and Venus, give similar results confirming a certain possibility to distinguish the forces of gravity described by the Schwarzschild and Eddington-Robertson metrics. • A space experiment to detect deviations from a 'standard' gravity law is discussed. • The Sun, Earth, Venus in Eddington or Schwarzschild gravity make up the space lab. • The experiment scheme of a probe flight with two gravity assists (GA) is suggested. • Analytical & numerical computations of the probe flight are made with close results. • Two GAs at Venus and Earth definitely distinguish between the regarded gravity laws. [ABSTRACT FROM AUTHOR]

This article is an interview with Victor Poirier, a pioneer in the development of artificial heart technology. Poirier discusses his work with Dr. Edward Teller, a renowned nuclear physicist known for his contributions to the development of atomic and hydrogen bombs. Poirier explains how he ended up working with Teller and their involvement in developing nuclear-powered electrical systems. They later applied this technology to artificial heart systems, with Teller providing crucial information and recommending the use of Plutonium 238 as a fuel source. The proposed system was eventually accepted, and Poirier reflects on the honor and privilege of working with Teller on this project. [Extracted from the article]

We present a study on stellar properties of Lyman-alpha (Ly α) emitters at 5 < z < 8.2. We use 247 photometrically selected, lensed, high-redshift, low-luminosity galaxy candidates with spectroscopic follow-up. Of these, 38 are confirmed spectroscopically to be between 5 < z < 8.2 via detection of Ly α. For each galaxy and candidate, we estimate stellar mass, star formation rate, specific star formation rate, and mass-weighted age with spectral energy distribution fitting. We also measure the UV β slope and luminosity using values from photometry. We find no strong correlation between Ly α equivalent width and any of these properties, as well as no significant difference between the physical properties of Ly α emitters and candidates without Ly α detected. This lack of expected trends may be explained by a combination of the evolving opacity of the intergalactic medium at these redshifts as well as the unique phase space probed by our lensed sample. Via tests on other galaxy samples which show varying strengths of correlations, we conclude that if there exist any relationships between Ly α equivalent width and physical properties in the underlying population of faint galaxies, they are weak correlations. We also present the results of a spectroscopic search for C  iii ] emission in confirmed Ly α emitters at z ∼ 7, finding no C  iii ] detections, but putting constraints on strong active galactic nuclei activity and extreme nebular emission. [ABSTRACT FROM AUTHOR]

In this paper, a compact dual-polarized antenna with wide band and high isolation is proposed, which can be applied to the 5G WiFi frequency band. The antenna is composed of 2×2 arrayed patches and two orthogonal L-shaped probe structures with reduced middle patch width and loaded U-shaped slots. The proposed antenna achieves a compact size by eliminating the need for a complex feeding network, instead utilizing only two closely spaced L-shaped probes for feeding. The antenna's radiation modes excited by two ports are orthogonal in polarization direction, and each port can excite two linearly polarized radiation modes respectively within the operating frequency band, thereby achieving dual-linear polarization and wideband performance. The antenna is analyzed and designed using characteristic mode analysis (CMA). By reducing the patch middle width and loading U-shaped slots on the L-shaped probe of the antenna, the suppression of high-order modes, improvement of isolation, and reduction of cross-polarization levels are achieved. The size of the antenna is 0.54λ0 × 0.54λ0 × 0.068λ0 (λ0 is the free-space wavelength of central frequency). The measured bandwidth is 23.5% (4.73 GHz-5.99 GHz) with |S11| < -10 dB, |S21| < -27.9 dB, boresight gain of 4.8 dBi-6.2 dBi, and cross-polarization levels better than -23 dB. [ABSTRACT FROM AUTHOR]

The MoEDAL's Apparatus for Penetrating Particles (MAPP) Experiment is designed to expand the search for new physics at the LHC, significantly extending the physics program of the baseline MoEDAL Experiment. The Phase-1 MAPP detector (MAPP-1) is currently undergoing installation at the LHC's UA83 gallery adjacent to the LHCb/MoEDAL region at Interaction Point 8 and will begin data-taking in early 2024. The focus of the MAPP experiment is on the quest for new feebly interacting particles — avatars of new physics with extremely small Standard Model couplings, such as minicharged particles (mCPs). In this study, we present the results of a comprehensive analysis of MAPP-1's sensitivity to mCPs arising in the canonical model involving the kinetic mixing of a massless dark U(1) gauge field with the Standard Model hypercharge gauge field. We focus on several dominant production mechanisms of mCPs at the LHC across the mass-mixing parameter space of interest to MAPP: Drell-Yan pair production, direct decays of heavy quarkonia and light vector mesons, and single Dalitz decays of pseudoscalar mesons. The 95% confidence level background-free sensitivity of MAPP-1 for mCPs produced at the LHC's Run 3 and the HL-LHC through these mechanisms, along with projected constraints on the minicharged strongly interacting dark matter window, are reported. Our results indicate that MAPP-1 exhibits sensitivity to sizable regions of unconstrained parameter space and can probe effective charges as low as 8 × 10−4e and 6 × 10−4e for Run 3 and the HL-LHC, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the development and evaluation of the Proton Environment and Total ionizing dose (TID) Effect Monitor (PETEM) onboard a low Earth orbit (LEO) satellite for telecommunication test launched on 20th May 2022. The PETEM was developed to supply in-situ probe data of space environment and its effects for the space application of commercial off-the-shelf (COTS) components. At the same time, it is expected that the data can be useful for analyzing the proton distribution in South Atlantic Anomaly (SAA) and inner radiation belt. PETEM possesses the function of detecting high-energy protons and TID effects in LEO. Geant4 simulation was employed to design the semiconductor telescope of high-energy proton detector, which was designed to measure protons in the energy range of 5∼200 MeV. A circuit was developed to improve the accuracy of radiation-sensitive field-effect transistor (RadFET) measurements by accounting for the temperature dependence of the threshold voltage and calibration results showed its ability to provide reliable and accurate measurements of TID effects in real-time. We also present the results of in-flight tests, indicating that PETEM can reliably measure proton environment and TID effects. [ABSTRACT FROM AUTHOR]

Harry Thornton and Leslie Rae were the Editors of the BAA Lunar Section publication The Moon from 1953 to 1967, during which period charting the lunar surface visually was superseded by professional astronomical photography and early space probe imagery. As a result, lunar contributions to The Moon dried up and, after Rae's resignation, the publication ceased. Thornton and Rae were very prominent figures in the BAA of the 1 950s and 1960s, yet no obituaries of them were ever published in the journal. The aim of this paper is to address those omissions. [ABSTRACT FROM AUTHOR]

Periodic orbit families around asteroids serve as potential trajectories for space probes, mining facilities, and deep space stations. Bifurcations of these families provide additional candidate orbits for efficient trajectory design around asteroids. While various bifurcations of periodic orbit families around asteroids have been extensively studied, period-multiplying bifurcations have received less attention. This paper focuses on studying period-multiplying bifurcations of periodic orbit families around asteroids. In particular, orbits with periods of approximately 7 and 17 times that of the rotational period of asteroid 216 Kleopatra were computed. The computation of high-period orbits provides insights into the numerical aspects of simulating long-duration trajectories around asteroids. The previous literature uses single-shooting and multiple-shooting methods to compute bifurcations of periodic orbit families around asteroids. Computational difficulties were encountered while using the shooting methods to obtain period-multiplying bifurcations of periodic orbit families around asteroids. This work used the Legendre–Gauss collocation method to compute period-multiplying bifurcations around asteroids. This study recommends the use of collocation methods to obtain long-duration orbits around asteroids when computational difficulties are encountered while using shooting methods. [ABSTRACT FROM AUTHOR]

A search for dark matter particles is performed using events with a pair of W bosons and large missing transverse momentum. Candidate events are selected by requiring one or two leptons (ℓ = electrons or muons). The analysis is based on proton-proton collision data collected at a center-of-mass energy of 13 TeV by the CMS experiment at the LHC and corresponding to an integrated luminosity of 138 fb−1. No significant excess over the expected standard model background is observed in the ℓνqq and 2ℓ2ν final states of the W+W− boson pair. Limits are set on dark matter production in the context of a simplified dark Higgs model, with a dark Higgs boson mass above the W+W− mass threshold. The dark matter phase space is probed in the mass range 100–300 GeV, extending the scope of previous searches. Current exclusion limits are improved in the range of dark Higgs masses from 160 to 250 GeV, for a dark matter mass of 200 GeV. [ABSTRACT FROM AUTHOR]

The scientific portrayal of apes at the turn of the twentieth century functioned as a rich space to probe the border between humans and the nonhuman world and to rethink the tenets of evolution. To take up these themes, Nicaraguan author Hernán Robleto (1895-1968), whose theatrical and narrative work was otherwise characterized by a costumbrista realist style, turned to the speculative genres of science fiction and fantasy in his novel Una mujer en la selva (1936). Inspired by the jungle adventure fantasies of Edgar Rice Burroughs and by the hit Hollywood film King Kong (1933), Robleto's novel offers a surprising fable about a ladina woman who falls in love with a giant ape in Nicaragua's jungled Atlantic coast. The erotic interspecies encounter is ontologically transformative; after the death of her primate lover, the protagonist becomes a legendary ape woman who haunts the social body. Allegorically, the novel deploys the giant ape as a stand-in for the marginalized Afro-descendant peoples of Nicaragua's east coast. The problematic collapse of blackness into the figure of the ape underscores how ladino writers like Robleto struggled to write about Afro-Indigenous populations in realist terms. The abstraction of blackness into the figure of the ape is a racist reification of Black animality, but at the same time, the fantastical interspecies romance in Robleto's novel tentatively advocates for a non-normative model of national coupling grounded in the Atlantic coast. [ABSTRACT FROM AUTHOR]

One manifestation of light-Weyl fermion interaction is the emergence of chiral magnetic effects under magnetic fields. Probing real space magnetic responses at terahertz (THz) scales is challenging but highly desired, as the local responses are less affected by the topologically trivial inhomogeneity that is ubiquitous in spatially averaged measurements. Here, we implement a cryogenic THz microscopy instrument under a magnetic field environment—a task only recently achieved. We explore the technical approach of this system and characterize the magnetic field's influence on our AFM operation by statistical noise analysis. We find evidence for local near-field spatial variations in the topological semimetal ZrTe5 up to a 5-Tesla magnetic field and obtain near-field THz spectra to discuss their implications for future studies on the chiral magnetic effect. [ABSTRACT FROM AUTHOR]

The remarkably long distances covered by deep space probes result in extremely weak downlink signals, which poses great challenges for ground measurement systems. In the current climate, improving the comprehensive utilization of downlink signal power to increase the detection distance or enhance the measurement accuracy is of great significance in deep space exploration. Facing this problem, we analyze the delta Differential One-way Range (ΔDOR) error budget of the X-band of the China Deep Space Network (CDSN). Then, we propose a novel interferometry method that detunes one group of DOR beacons and reuses the clock components of regenerative pseudo-code ranging signals for interferometry delay estimation. The primary advantage of this method is its ability to enhance the power utilization efficiency of downlink signals, thereby facilitating more efficient tracking and measurement without necessitating additional design requirements for deep space transponders. Finally, we analyze and verify the correctness and effectiveness of our proposed method using measured data from CDSN. Our results indicate that the proposed method can save approximately 13% of the downlink signal power and increase the detection distance by about 6.25% using typical modulation parameters. Furthermore, if the relative power of other signal components remains unchanged, the power of the DOR tone can be directly increased by more than 100%, improving the deep space exploration ability more significantly. [ABSTRACT FROM AUTHOR]

Pore-size distribution (PSD) of soil is a fundamental property that determines flows of water, heat, chemicals, and electricity and controls distributions of stress and deformation. PSD can be intrinsically related to the soil–water retention curve (SWRC), which is a constitutive relationship describing how the soil skeleton retains pore water via adsorption and capillarity. A general framework to quantify soil's PSD is proposed by first fitting an analytical SWRC model to experimental water retention curves that explicitly separate the SWRC into an adsorptive SWRC and a capillary SWRC. The PSD is then estimated at incremental steps by combining the capillary SWRC and the conventional Young–Laplace equation relating capillary pressure to pore size. Cumulative and density PSD curves for 11 soils covering a wide spectrum of soil types are determined and compared with the PSD functions independently measured using mercury intrusion porosimetry (MIP). Good agreement is observed in the estimated pore size range, distribution pattern, and peak position determined from the two different methods. Differences observed in the methods are attributed to differences inherent in the use of wetting and nonwetting fluids to probe the pore space. The SWRC-based method generally characterizes pore sizes ranging from 100 to 0.02 μm with a major peak located within a pore diameter range of 1–10 μm. As the clay content increases, a secondary peak becomes evident at smaller pore sizes (about 0.01–0.1 μm), where the bimodal pattern reflects the dual-porosity microstructure commonly observed for clayey soils. For soils containing swelling clays, PSD can change substantially with variation in water content; thus, the water-based method is more appropriate than MIP for applications to geotechnical engineering practice. [ABSTRACT FROM AUTHOR]

The article explores the concept of opacity in basements and its implications for ethnographic research. The author challenges the idea that the role of the ethnographer is to bring objects and social relations in basements "to light," instead proposing opacity as a means of preserving diversity. The author suggests three lines of inquiry: recrafting participant observation as observer participancy, shifting towards sonic modes of encounter and description, and practicing an ethics of reciprocal debasement in ethnographic encounters. The article also discusses the tension between personal opacity and the researcher's responsibility to attend to the basements of others. [Extracted from the article]

Space probes are always obstructed by floating objects in the atmosphere (clouds, haze, rain, etc.) during imaging, resulting in the loss of a significant amount of detailed information in remote sensing images and severely reducing the quality of the remote sensing images. To address the problem of detailed information loss in remote sensing images, we propose an end-to-end detail enhancement network to directly remove haze in remote sensing images, restore detailed information of the image, and improve the quality of the image. In order to enhance the detailed information of the image, we designed a multi-scale detail enhancement unit and a stepped attention detail enhancement unit, respectively. The former extracts multi-scale information from images, integrates global and local information, and constrains the haze to enhance the image details. The latter uses the attention mechanism to adaptively process the uneven haze distribution in remote sensing images from three dimensions: deep, middle and shallow. It focuses on effective information such as haze and high frequency to further enhance the detailed information of the image. In addition, we embed the designed parallel normalization module in the network to further improve the dehazing performance and robustness of the network. Experimental results on the SateHaze1k and HRSD datasets demonstrate that our method effectively handles remote sensing images obscured by various levels of haze, restores the detailed information of the images, and outperforms the current state-of-the-art haze removal methods. [ABSTRACT FROM AUTHOR]

Recent startups and university space activities extend to cis -lunar and near-Earth interplanetary field. One of the biggest hurdles in those missions is in the orbit determination based on the range measurements, while the radio transmission and reception capability becomes within those small organizations' facilities. Also, about the navigation in cis -lunar space, conventional GNSS (Global Navigation Satellite System) real time positioning is hardly available and some alternative methods have been sought. The most straight forward approach is to be supported by the space agencies' facilities for the range measurement with the transponders onboard the probes. However, it depends on the facilities availability and also on the relatively expensive, old and analogue transponders. This paper presents a new method deriving from the GNSS based devices. It does not require the transponders but inexpensive radio circuits easily built. And both the probes and the ground stations have only to be equipped with the common and simple inexpensive devices. The method enables the small organizations to perform autonomous operation of the probes in a distance beyond the moon's orbit. The paper first presents the latest test data obtained during the development using the Software Defined Radio (SDR) boards. • Low-Cost Ranging Measurement for Deep Space beyond Cis-Lunar Region. • Real Test Results using Software Defined Radio Boards, Hardware. • Semi-Real-Time and Simultaneous Range Measurement and Clock Synchronization. • Absolute Clock Relay Capability via A Pair of Spacecraft. [ABSTRACT FROM AUTHOR]

DNA biosensors are promising candidates for the development of point‐of‐care diagnosis methods. They can be inserted in microfluidic platforms, are often non‐expensive, and can be produced for a variety of targeted analytes. However, their development faces several challenges, some of which arise from their surface design. Among the characteristics which affect the binding efficiency of DNA probes to their targeted genes, the packing density and lateral spacing of the probe sequences must be controlled to provide enough binding sites and avoid crowding effect. It has also been demonstrated that increasing the space between the probe and the substrate can enhance the sensitivity of the sensing surface. Herein, we describe a methodology to control the vertical distance between DNA probes and a glass support, and lateral spacing between the probes. Such functionalization strategy could help the development of sensing surface with high hybridization density, and therefore high sensitivity. [ABSTRACT FROM AUTHOR]

US spacefaring efforts have received extensive media attention in recent years, and research suggests that media consumption is related to audience members' support for space exploration in broad terms. The present study extends this line of investigation by testing how three different forms of media use – science fiction viewing, documentary viewing, and news media consumption – predict public attitudes about a range of government space policy endeavors. The initiatives examined include sending telescopes and robotic probes into space, sending astronauts to the Moon and Mars, monitoring asteroids and comets that might strike the Earth, searching for unidentified flying objects and extraterrestrial intelligence, and creating a Space Force. Building on theories of genre-specific cultivation, perceptual realism, narrative transportation, and framing, the analyses use data from two nationally representative surveys conducted in 2022 (N = 996 and N = 1,015). The results indicate that science fiction viewing, documentary viewing, and news use are related to support for US space endeavors, but these relationships differ across both specific media types and specific initiatives. The findings carry potential implications for understanding the future sustainability of space initiatives in terms of popular support. [ABSTRACT FROM AUTHOR]

A Langmuir Probe (LP) measures currents from incident charged particles as a function of the applied bias voltage. While onboard a spacecraft the particles are either originated from the surrounding plasma, or emitted (e.g. through photoemission) from the spacecraft itself. The obtained current–voltage curve reflects the properties of the plasma in which the probe is immersed into, but also any photoemission due to illumination of the probe surface: As photoemission releases photoelectrons into space surrounding the probe, these can be recollected and measured as an additional plasma population. This complicates the estimation of the properties of the ambient plasma around the spacecraft. The photoemission current is sensitive to the extreme ultraviolet (UV) part of the spectrum, and it varies with the illumination from the Sun and the properties of the LP surface material, and any variation in the photoelectrons irradiance can be measured as a change in the current voltage curve. Cassini was eclipsed multiple times by Saturn and the main rings over its 14 yr mission. During each eclipse the LP recorded dramatic changes in the current–voltage curve, which were especially variable when Cassini was in shadow behind the main rings. We interpret these variations as the effect of spatial variations in the optical depth of the rings and hence use the observations to estimate the optical depth of Saturn's main rings. Our estimates are comparable with UV optical depth measurements from Cassini's remote sensing instruments. [ABSTRACT FROM AUTHOR]

Images captured by deep space probes exhibit large-scale variations, irregular overlap, and remarkable differences in field of view. These issues present considerable challenges for the registration of multi-view asteroid sensor images. To obtain accurate, dense, and reliable matching results of homonymous points in asteroid images, this paper proposes a new scale-invariant feature matching and displacement scalar field-guided optical-flow-tracking method. The method initially uses scale-invariant feature matching to obtain the geometric correspondence between two images. Subsequently, scalar fields of coordinate differences in the x and y directions are constructed based on this correspondence. Next, interim images are generated using the scalar field grid. Finally, optical-flow tracking is performed based on these interim images. Additionally, to ensure the reliability of the matching results, this paper introduces three methods for eliminating mismatched points: bidirectional optical-flow tracking, vector field consensus, and epipolar geometry constraints. Experimental results demonstrate that the proposed method achieves a 98% matching correctness rate and a root mean square error of 0.25 pixels. By combining the advantages of feature matching and optical-flow field methods, this approach achieves image homonymous point matching results with precision and density. The matching method exhibits robustness and strong applicability for asteroid images with cross-scale, large displacement, and large rotation angles. [ABSTRACT FROM AUTHOR]

The use of electro-optical imaging system for commercial, military, or surveillance missions, as well as space scientific missions, dates back to the first successful operation aboard the US Explorer-6 spacecraft, which was the first spacecraft to capture low-resolution images of the Earth's surface, and the Luna-3 space probe, which was the first spacecraft to send images of the lunar far side, in 1959. The technology underlying EO system have evolved over time, with advances in optics, electronics, and materials science leading to the development of more sophisticated and capable imaging sensors. Furthermore, the technological advances in sensors, optics, mechanics, material, signal and image processing algorithms have allowed EO payloads to become smaller, lighter, and more efficient while still providing high-quality imagery. Over 840 small spacecraft weighing less than 500 kg were launched, with 80% in the constellation segment and 20% as monolithic satellites (i.e., single spacecraft equipped with an electro-optical imaging instrument launched into space for various missions). In this paper, the electro-optical imaging systems of these spacecraft were reviewed using data from a variety of sources, including peer-reviewed journal publications, conference proceedings, mission webpages, and other publicly available satellite databases. Furthermore, the technological and commercial expansion of small spacecraft (< 500 kg) equipped with electro-optical imaging systems, as well as EO-COTS parametric performance values such as GSD, spectral range, field of view, and sensor type, are discussed through 2023, divided by spacecraft type: SSO satellites, Small spacecraft constellation, Deep space spacecraft, and EO commercialization. • The evolution of electro-optical imaging system. • Small spacecraft missions equipped with EO sensors. • Constellation of small satellite missions can provide comparable capability. • The advantages of an EO-based deep space spacecraft mission. • The main factors driving the market trend toward small spacecraft optical payload. [ABSTRACT FROM AUTHOR]

The paper adopts a close textual analysis of the representation of same sex desire in Geetanjali Shree's novel The Roof Beneath Their Feet (2013), originally published in Hindi as Tirohit (2007), as it tends to dismantle the domestic realm as a heteronormative space. It focuses on clandestine and parallel arrangements of togetherness forged out of love and longing formed within the heterosexual family, which imparts a sense of belonging. Using belonging as a conceptual framework, it examines how female sexual subjectivity is mediated through spatial markers of intimacy as evident through the use of sub-urban local community spaces (mohalla), secrecy, and gossip as modes of articulation. Rather than understanding families in terms of hetero/homosexual binary, it tries to locate same sex familial belonging within specific networks of power relationships such as class, gender, and community thereby outlining the shifting connotations of desire, visibility, invisibility and female sexual subjectivity. Thus, drawing from Feminist Geography and Queer theory, it demonstrates how same sex belonging, which is manifested through the "experiencing" of desire, is both performatively constituted and also influenced by the politics of intersectionality. [ABSTRACT FROM AUTHOR]

The precise prediction of polar motion parameters is needed for the astrogeodynamics, navigation and positioning of the deep space probe. However, the current prediction methods are limited to predicting polar motion for specific periods, either short- or long-term. In this study, a sliding multilayer perceptron (MLP) method combined singular spectrum analysis (SSA) and autoregressive moving average (ARMA) for short- and long-term polar motion prediction was proposed. MLP was introduced into PM prediction due to its automatic learning characteristics and its ability to effectively process nonlinear and multi-dimensional data. The SSA was used to extract and predict the principal components of polar motion, while the remaining components were predicted using ARMA. In the meantime, SSA and ARMA were used to provide training data and target learning data for the MLP model. MLP input data were constructed by sliding processing with a window of 7 days, composed of n series of the same length (18 years). Finally, MLP was employed to predict the residuals generated during SSA and ARMA prediction. To evaluate the accuracy of the proposed method, the polar motion prediction was applied for a 364-day lead time based on the IERS EOP 14C04 product. The method outperformed the IERS Bulletin A, as demonstrated by the mean-absolute errors of the x and y components of polar motion on the 30th day, which were lower (5.14 mas and 3.37 mas, respectively) than those predicted by IERS Bulletin A (6.66 mas and 3.94 mas). Similarly, the mean-absolute errors on the 364th day were 17.79 mas and 16.29 mas, respectively, compared to the 19.24 mas and 18.81 mas predicted by IERS Bulletin A. [ABSTRACT FROM AUTHOR]

In type I seesaw models, the right-handed neutrinos are typically super-heavy, consistent with the generation of baryon asymmetry via standard leptogenesis. Primordial gravitational waves of cosmological origin provides a new window to probe such high scale physics, which would otherwise be inaccessible. By considering a global U(1)B−L extension of the type I seesaw model, we explore the connection between the heaviest right-handed neutrino mass and primordial gravitational waves arising from the dynamics of global cosmic string network. As a concrete example, we study a global U(1)B−L extension of the Littlest Seesaw model, and show that the inevitable GW signals, if detectable, probe the parameter space that can accommodate neutrino oscillation data and successful leptogenesis, while respecting theoretical constraints like perturbativity of the theory. Including CMB constraints from polarization and dark radiation leaves a large region of parameter space of the model, including the best fit regions, which can be probed by GW detectors like LISA and ET in the near future. In general, the GW detectors can test high scale type I seesaw models with the heaviest right-handed neutrino mass above 2.5 × 1014 GeV, assuming the perturbativity, and 7 × 1013 GeV assuming that the coupling between the heaviest right-handed neutrino and the U(1)B−L breaking scalar is less than unity. [ABSTRACT FROM AUTHOR]

Based on published evidence and our expert experience, we provide recommendations to maximize the efficacy, safety, efficiency, andcost-effectiveness of routine colonoscopy. High-quality colonoscopy begins with colon preparationusing a split or same-day dose and preferably a low-volume regimen for optimal patient tolerance and compliance. Successful cecal intubation can be achieved by choosing the correct colonoscope and using techniques to facilitate navigation through challenges such as severe angulations and redundant colons. Safety is a primary goal, and complications such as perforation and splenic rupture can be prevented by avoiding pushing through fixed resistance and avoiding loops in proximal colon. Furthermore, barotrauma can be avoided by converting to water filling only (no gas insufflation) in every patient with a narrowed, angulated sigmoid. Optimal polyp detection relies primarily on compulsive attention to inspection as manifested by adequate inspection time, vigorous probing of the spaces between haustral folds, washing and removing residual debris, and achieving full distention. Achieving minimum recommended adenoma detection rate thresholds (30% in men and 20% in women) is mandatory, and colonoscopists should aspire to adenoma detection rate approaching 50% in screening patients. Distal attachments can improve mucosal exposure and increase detection while shortening withdrawal times. Complete resection of polyps complements polyp detection in preventing colorectal cancer. Cold resection is the preferredmethod for all polyps<10mm. For effective cold resection, an adequate rim of normal tissue should be captured in the snare. Finally, cost-effective high-quality colonoscopy requires the procedure not be overused, as demonstrated by following updated United States Multi Society Task Force on Colorectal Cancer postpolypectomy surveillance recommendations. [ABSTRACT FROM AUTHOR]

Cylindrical multi-degree-of-freedom (multi-DOF) ultrasonic motors have the potential to significantly reduce motor size compared to other ultrasonic motors. They find applications in various systems, including micro-robot joints and space probes. This paper proposes a 3-DOF cylindrical ultrasonic motor with hybrid vibration modes. Hybrid vibration modes encompass non-standard longitudinal and bending vibrations. The structure and operating principle of the motor are described first. COMSOL Multiphysics models the stator's vibration modes, frequency response, and 3-DOF motion. A motor prototype is manufactured and characterized to demonstrate the output characteristics of the motor. The results indicate that the motor has a no-load speed of 37 rpm along the x- and y-axes and up to 77 rpm along the z-axis. The maximum output torque of the motor is 25 Nm. The motor is low in height and compact, providing a method for further reducing the stator length of motors of the same type. [ABSTRACT FROM AUTHOR]

The dead zone in ultrasonic time-of-flight diffraction (TOFD) restricts the quantitation of near-surface defects. Alternative TOFD techniques introduce other tip-diffracted/scattered waves with longer propagation times to implement defect detection, but the applicability is influenced due to ignoring the change of acoustic path of the diffracted shear wave in wedge. In this paper, the mode-converted wave (MCW) method is exemplified to analyze the propagation path of diffracted shear wave and the change of the received point in wedge. On this basis, the corrected MCW method is proposed by establishing the relationship between the propagation time of MCW and defect depth according to Fermat's principle. The simulation and experiments show that the depth of near-surface dead zone is reduced by 60% with the corrected MCW method. The positioning errors of the defects in the aluminum alloy sample with a thickness of 20.0 mm are no more than 0.15 mm by using the TOFD probes with 10 MHz center frequency and 40 mm probe center spacing (PCS) and the 60° wedges. Compared to the conventional MCW method, the corrected method widens the range of applicable TOFD signals in B-scan images and reduces the measurement errors of defect depths to within 3.5% under ideal conditions. [ABSTRACT FROM AUTHOR]

Micronozzles operating with vacuum exit conditions find applications in satellite propulsion systems and aerodynamic separation processes. The increased demand for cube satellite applications and the need for real-time fast response sensors for monitoring pollutants and toxic releases have created interest in micronozzles operating under multi-scale flow regimes. The objective of this paper is to present a summary of the research on supersonic micronozzles that operate with vacuum exit conditions and are utilized in applications such as satellite attitude control, deep space probes, and binary mixture separation. The review covers various experimental programs and numerical techniques employed, along with analyzing the flow characteristics and their influence on the nozzle's performance. A brief description of experimental techniques adopted, trends in numerical methods, and the effect of various parameters such as size, shape, expansion ratio, surface roughness, Re, and wall heat transfer have been included. The review of simulation studies focuses on the DSMC method, the various approaches for modeling collision between particles, particles, and walls, and the simulation strategies. Comparisons are made to understand how well the DSMC method can predict the flow. The current understanding of the flow behavior under various exit conditions is summarized. Major flow features, experimentation, simulation approach trends, design considerations, manufacturing methods, etc. are discussed. The review concludes by discussing the ongoing and future challenges, especially regarding experimental measurements in a vacuum and reducing computational expenses. [ABSTRACT FROM AUTHOR]

The paper examines the Assamese short story “Xomoi-Xeema” (2005) by Saurav Kumar Chaliha and the English poetry collection, Street on the Hill (2006), by Anjum Hasan to propose an expanded notion of Anglophone writing through multilingual readings of regional Indian literature and offer alternative modes of political inclusivity. It examines the role of English in Northeast Indian literary texts in articulating cosmopolitanism from a marginalized space and probing the linguistic frontiers of the postcolonial nation-state. Through this comparative reading, the essay envisions the relationships between region, nation, and world through a series of overlapping linguistic exchanges and provides an alternative understanding of world literature to current models focused on the English-language novel. [ABSTRACT FROM AUTHOR]