Continuous Range Research Articles

Direct Power Flow Controller With Continuous Full Regulation Range

Direct Power Flow Controller With Continuous Full Regulation Range

A Reconfigurable Soft Linkage Robot via Internal "Virtual" Joints.

Traditional robots derive their capabilities of movement through rigid structural "links" and discrete actuated "joints." Alternatively, soft robots are composed of flexible materials that permit movement across a continuous range of their body and appendages and thus are not restricted in where they can bend. While trade-offs between material choices may restrain robot functionalities within a narrow spectrum, we argue that bridging the functional gaps between soft and hard robots can be achieved from a hybrid design approach that utilizes both the reconfigurability and the controllability of traditional soft and hard robot paradigms. In this study, we present a hybrid robot with soft inflated "linkages," and rigid internal joints that can be spatially reconfigured. Our method is based on the geometric pinching of an inflatable beam to form mechanical pinch-joints connecting the inflated robot linkages. Such joints are activated and controlled via internal motorized modules that can be relocated for on-demand joint-linkage configurations. We demonstrate two applications that utilize joint reconfigurations: a deployable robot manipulator and a terrestrial crawling robot with tunable gaits.

Liquid Crystal Metasurface for On‐Demand Terahertz Beam Forming Over 110° Field‐Of‐View

AbstractThe terahertz spectral region, which bridges between electronics and optics, is poised to play an important role in the development of transformative wireless communication and imaging systems with unprecedented functionality. Currently, a major challenge in terahertz technology is to develop high‐performance terahertz beam‐forming devices that can dynamically shape the terahertz radiation in a flexible manner. Existing terahertz beam‐forming devices have limited coding bits, field‐of‐view, and beam gain. Here, a reconfigurable liquid crystal‐integrated terahertz metasurface is experimentally demonstrated, with each metasurface unit cell being independently addressable. The metasurface has a 260° continuous phase tuning range with a liquid crystal layer thickness of only 1% of the free‐space wavelength. The terahertz wave diffracted from the metasurface can be steered toward a wide range of directions is shown, covering a record‐large 110° field‐of‐view with a peak gain of 25 dBi. The metasurface also features a low power consumption and sub‐second switching time. Furthermore, the formation of multiple terahertz beams is demonstrated, with the direction of each beam and the power ratio between beams adjustable on demand. The proposed liquid crystal metasurface possesses compelling prospects for future terahertz communication and imaging applications.

Robust low-noise 795-nm single-frequency fiber laser with continuous frequency tuning

This study presents a highly efficient and low-noise all-fiber single-frequency (SF) 795-nm laser system realized using a simple and robust single-pass frequency-doubling configuration. The foundation of the system is a 1590-nm erbium-doped fiber amplifier operating in a master oscillator power amplifier configuration seeded by a distributed feedback semiconductor laser at 1590.52 nm. The main amplifier exhibits an exceptional amplification efficiency of 30.5 %. By utilizing a periodically poled lithium niobate waveguide, the 795-nm laser is frequency-doubled with an output power reaching 2.3 W, corresponding to an optical efficiency of 44 % of the fundamental laser. Crucial to its application in precision measurements and quantum technologies, the SF 795-nm laser exhibits a relative intensity noise close to −150 dBc/Hz in the frequency range of 0.1 to 10 MHz. Additionally, a continuous frequency-tuning range of 11.7 GHz is achieved by modulating the current with a 2.5-mA 1-Hz triangular wave. Notably, this is the first report on an all-fiber SF 795-nm laser system.

Clinical outcomes of a toric continuous range of vision presbyopia-correcting intraocular lens.

To evaluate the clinical outcomes of the toric version of a presbyopia-correcting intraocular lens (IOL) based on the combination of a diffractive-based extended depth-of-focus (EDOF) pattern and a diffractive multifocal platform. Miranza COI Bilbao, Bilbao, Spain. Prospective case series. 35 patients (51 to 84 years) with corneal astigmatism ranging from 0.75 to 2.19 diopters (D) undergoing bilateral cataract surgery with implantation of the Synergy Toric II IOL were evaluated during a 3-month follow-up. Visual acuity, refraction, defocus curve, and patient-reported outcomes with the Catquest-9SF questionnaire were analyzed. A vectorial analysis was used to analyze the accuracy of astigmatic correction. Mean 3-month monocular postoperative uncorrected distance, intermediate (80 cm) and near (40 cm) visual acuities were 0.06 ± 0.11 logMAR, 0.13 ± 0.12 logMAR, and 0.13 ± 0.09 logMAR, respectively. Mean monocular distance-corrected intermediate (80 cm) and near visual acuity (40 cm) were 0.11 ± 0.12 logMAR and 0.10 ± 0.10 logMAR, respectively. Mean binocular defocus curve showed visual acuities of 0.10 logMAR or better for defocus levels from +0.50 to -2.50 D. Residual cylinder was within ±0.50 D in 97.0% of eyes. The surgically induced astigmatism prediction error ranged between -0.49 D and 0.50 D, with a mean value of 0.04 ± 0.16 D. Mean absolute IOL rotation was 3.79 ± 2.94 degrees. Significant improvements were found in all Rasch-calibrated scores obtained with Catquest-9SF ( P < .001). The implantation of the toric presbyopia-correcting IOL evaluated provides an efficacious astigmatic correction while providing a fully restoration of the visual function across different distances.

Shift from income breeding to capital breeding with latitude in the invasive Asian shore crab Hemigrapsus sanguineus

Organisms vary in the timing of energy acquisition and use for reproduction. Thus, breeding strategies exist on a continuum, from capital breeding to income breeding. Capital breeders acquire and store energy for breeding before the start of the reproductive season, while income breeders finance reproduction using energy acquired during the reproductive season. Latitude and its associated environmental drivers are expected to heavily influence breeding strategy, potentially leading to latitudinal variation in breeding strategies within a single species. We examined the breeding strategy of the Asian shore crab Hemigrapsus sanguineus at five sites spanning nearly 10° of latitude across its invaded United States range. We hypothesized that the primary breeding strategy of this species would shift from income breeding to capital breeding as latitude increases. We found that though this species’ breeding strategy is dominated by capital breeding throughout much of the range, income breeding increases in importance at lower latitudes. This latitudinal pattern is likely heavily influenced by the duration of the foraging and breeding seasons, which also vary with latitude. We also found that reproductive characteristics at the northern and southern edges of the invaded range were consistent with continued range expansion. We suggest that the reproductive flexibility of the Asian shore crab is a key facilitator of its continued invasion success. Our results highlight the influence of latitude on the breeding strategy of a species and emphasize the need for further research regarding the ecological importance and implications of flexibility in breeding strategies within species.

No mitochondrial DNA variation in COI gene among widely distributed populations of a parthenogenetic praying mantid: a biogeographic puzzle

Abstract The endemic North American praying mantid, Brunneria borealis Scudder (1896), is obligatorily parthenogenic and wingless. The species is both geographically widespread, distributed over an essentially continuous pericoastal range of more than 2,400 km from eastern Texas to central North Carolina, and abundant in early-stage successional old fields. We used mitochondrial cytochrome oxidase I (COI) analysis to examine the genetic similarities among specimens of this insect and collected from 7 states along this range of distribution. We found no variations in the mitochondrial COI gene, which suggests that this wide geographic distribution of the species is surprisingly recent. We hypothesize that its obligatory parthenogenic status may be an accident of colonization of North America by a single facultative parthenogenic female, and the subsequent distribution was most likely achieved by inadvertent human transport.

Abstract MP37: Insomnia is Associated With Fatty Acid and Oxylipin Inflammatory Biomarkers in the Hispanic Community Health Study/Study of Latinos

Introduction: Insomnia symptoms are prevalent in Hispanic/Latino adults, and insomnia is a risk factor for cardiometabolic disease, possibly through dysregulated inflammatory pathways. However, existing evidence has largely focused on non-specific and downstream inflammatory biomarkers. Informed by prior research, we hypothesized that insomnia promotes chronic low-grade inflammation by disrupting the physiological balance between upstream bioactive fatty acids and oxylipins. Objective: To evaluate associations between insomnia and 81 upstream bioactive fatty acid and oxylipin inflammatory biomarkers in the population-based Hispanic Community Health Study/Study of Latinos (HCHS/SOL). Methods: After excluding night and rotating shift workers, participants were 14,439 HCHS/SOL adults (mean age: 46 y, 61% female, 62% with education ≥ high school degree). Insomnia was measured using the Women’s Health Initiative Insomnia Rating Scale (WHIIRS). We used the WHIIRS score as a continuous (range 0-20, with higher scores indicating greater severity) and categorical variable (WHIIRS ≥ 9, indicating clinically significant insomnia). The 81 oxylipins and fatty acids were profiled in fasting blood samples using non-targeted liquid chromatography-mass spectrometry and annotated based on mass-to-charge ratio, retention time, and spectra. Cross-sectional associations between rank normalized oxylipins and fatty acids with insomnia were assessed using survey-weighted multivariable linear regression adjusting for confounders (age, sex, center, Hispanic background group, education, smoking, alcohol use, the alternative healthy eating index, physical activity, and body mass index). We addressed multiple comparisons using a false discovery rate &lt;0.05. Results: The mean WHIIRS score was 7.1 (standard deviation: 5.4) and 36% displayed clinically significant insomnia. The WHIIRS showed statistically significant positive associations with 7 fatty acids (nervonic, docosadienoic, palmitoleic, eicosanoic, docosaenoic, behenic, and lignoceric acid) and 4 oxylipins (HpODE, leukotriene/HpETE/DiHETE/prostaglandin, HOTrE/oxoODE, and an oxylipin with unknown biological pathway). Clinically significant insomnia defined categorically showed statistically significant positive associations with 3 fatty acids and 3 oxylipins, all of which were also identified in the continuous WHIIRS analysis (see above). Identified fatty acids and oxylipins included both putative pro-inflammatory (e.g., HpODE) and anti-inflammatory (e.g., nervonic acid) compounds. Conclusions: Insomnia, like cardiometabolic disease, is associated with low-grade inflammation. The directionality of these relationships and degree to which associations between chronic inflammation with cardiometabolic disease and insomnia reflects overlapping pathways warrants further investigation.

Narrow linewidth laser based on a sidewall grating active distributed Bragg reflector.

We demonstrated a narrow linewidth semiconductor laser based on a deep-etched sidewall grating active distributed Bragg reflector (SG-ADBR). The coupling coefficients and reflectance were numerically simulated for deep-etched fifth-order SG-ADBR, and a reflectance of 0.86 with a bandwidth of 1.04 nm was obtained by the finite element method for a 500-period SG-ADBR. Then the fifth-order SG-ADBR lasers were fabricated using projection i-line lithography processes. Single-mode lasing at 1537.9 nm was obtained with a high side-mode suppression ratio (SMSR) of 65 dB, and a continuous tuning range of 10.3 nm was verified with SMSRs greater than 53 dB. Furthermore, the frequency noise power spectral density was characterized, from which a Lorentzian linewidth of 288 kHz was obtained.

Interfering sensed input classification model using assimilated whale optimization and deep Q-learning for remote patient monitoring

The Internet of Medical Things (IoMT)-based Remote Patient Monitoring (RPM) systems provide real-time data and insights about patients' conditions without the need for constant physical visits to healthcare facilities. The wearable sensors are responsible for sensing the psychological vitals of humans at different intervals to detect their precise health status. This article introduces an Interfering Input Classification Model (IICM) for addressing the continuous and discrete data extraction issues in RPM. The proposed model hybridizes whale optimization and deep-Q-learning for classification and connectivity identification between different interval data. The sensed information is segregated as discrete and continuous using the search process termination of the whales. Such classified data is validated for the maximum discreteness and its interconnection between the previous sequences. This interconnection is performed using Q-learning based on different state changes through continuous clinical range correlations. The proposed model exemplifies continuous and discrete signals (data) for abnormality detection and diagnosis recommendation. Thus the proposed model is reliable in improving the classification ratio and accuracy with fewer errors. The experimental values of the proposed model are as follows: IICM enhances classification by 6.65%, signal identification by 6.63%, and classification accuracy by 10.08%. This model reduces classification time by 9.51% and error by 10.14% for different ranges of inputs.

New record of the slimy eel Eptatretus polytrema (Girard, 1855) (Myxiniformes, Myxinidae) in the extreme north of Chile

We report the capture of a single specimen of the slimy eel Eptatretus polytrema (Girard, 1855) off the coast of the city of Arica, northern Chile. This &amp;#64257;nd extends the currently known range of the species by 1,600 km northwards from the city of Caldera (Atacama Region) to Puerto Montt (Lake Region). We discuss the importance of &amp;#64257;nding this species in the extreme north of Chile and the need for additional sampling to con&amp;#64257;rm the continuous range of E. polytrema between Caldera and Arica.

Virulence Spectra of Hungarian Pyrenophora teres f. teres Isolates Collected from Experimental Fields Show Continuous Variation without Specific Isolate × Barley Differential Interactions.

Pyrenophora teres f. teres (Ptt), the causal agent of net form net blotch (NFNB) disease, is an important and widespread pathogen of barley. This study aimed to quantify and characterize the virulence of Ptt isolates collected from experimental fields of barley in Hungary. Infection responses across 20 barley differentials were obtained from seedling assays of 34 Ptt isolates collected from three Hungarian breeding stations between 2008 and 2018. Twenty-eight Ptt pathotypes were identified. Correspondence analysis followed by hierarchical clustering on the principal components and host-by-pathogen GGE biplots suggested a continuous range of virulence and an absence of specific isolate × barley differential interactions. The isolates were classified into four isolate groups (IG) using agglomerative hierarchical clustering. One IG could be distinguished from other IGs based on avirulence/virulence on one to five barley differentials. Several barley differentials expressed strong resistance against multiple Ptt isolates and may be useful in the development of NFNB-resistant barley cultivars in Hungary. Our results emphasize that the previously developed international barley differential set needs to be improved and adapted to the Hungarian Ptt population. This is the first report on the pathogenic variations of Ptt in Hungary.

Home Care Worker Continuity in Home-Based Long-Term Care: Associated Factors and Relationships With Client Health and Well-Being.

Despite the importance of provider continuity across healthcare settings, continuity among home care workers who provide hands-on long-term care is understudied. This project describes home care worker continuity, identifies factors associated with increased continuity, and examines associations between continuity and client outcomes. We conducted a retrospective cohort study of clients receiving Medicaid-funded home-based long-term care (n = 3,864) using insurance plan and home care agency data from a large nonprofit organization. We estimated home care worker continuity for clients between 6-month clinical assessments using Bice-Boxerman scores. We then used generalized estimating equations to model associations between home care worker continuity and (1) client characteristics (e.g., cognitive impairment), and (2) client functional, health, and psychosocial outcomes. While home care worker continuity was lowest for clients receiving the most weekly care hours, a range of continuity existed across all levels of care need. Those who were male, older, Asian/Pacific Islander/Native American, cognitively impaired, and functionally impaired had lower continuity. Higher home care worker continuity was significantly associated (p < .05) with fewer falls, a higher likelihood of functional improvement/stabilization, and fewer depressive symptoms. The finding that home care worker continuity is associated with the health and well-being of home-based long-term care clients underscores the importance of building high-quality relationships in long-term care. Continued efforts are necessary to understand and advance home care worker continuity and to identify other aspects of the home care experience that benefit those receiving long-term care at home.

Study on the variation law of shock wave on the surface of landmine shell under touchdown explosion

To study the variation law of shock wave pressure load on the surface of a certain type of landmine installed on the ground when explosive contact ground explosion, the TNT (C7H5N3O6) contact ground explosion experiments were conducted. Using the pressure test device that simulates the shape of a certain type of landmine to test the shock wave pressure load on its side and top surface respectively. Combined with the numerical simulation, studied the variation law of shock wave overpressure peak, positive pressure action time, and specific impulse on the side and top surface of the landmines at different scaled distances. The results show that the scaled distance less than 1.453 m/ kg1/3 is the range of near-range explosion. In this range, the shock wave pressure time history curve shows multiple peaks due to the combined action of the shock wave and detonation products. The closer to the explosion source, the pressure peak generated by the detonation product is significantly higher than the shock wave pressure peak, and the propagation speed of the shock wave is faster than that of detonation products. With the further increase of the blast center distance, the positive pressure action time of the shock wave on the side and top surface of the landmine it was increased significantly. The specific impulse of the shock wave on the side of the landmines is significantly higher than that on the top surface of the device at the same scaled distance. In the range of scaled distance less than 1.937 m/kg1/3, the specific impulse of the shock wave on both the side and top surfaces of the landmines increases at first and then decreases later, and its variation curve shows an obvious triangle. With the increase of the explosive quality, the rate of rise and attenuation of specific impulse of the shock wave is faster. With the further increase of blasting center distance, the specific impulse of the shock wave on the side and the top surface of the landmines tends to be equal at the same scaled distance, the continuous range is wide, and the explosive quality has little effect on it.

Design of an efficiency enhanced wideband Doherty power amplifier based on synthesising of a modified harmonic‐control load modulation network

AbstractA design of a broadband Doherty power amplifier (DPA) using a novel harmonic control network (HCN) is presented. The DPA structure focused on manipulating harmonic components using this new HCN to enhance the bandwidth of operation and power efficiency. The proposed HCN combines a third harmonic suppression network (THSN) with the second harmonic impedance inverter circuit (SHIIC). In the design, the second harmonic component of the main transistor and the peaking transistor are short‐circuited by their associated SHIIC. Additionally, the carefully designed SHIIC and THSN circuit placed between the main and peaking transistors realise open circuit conditions at the third harmonic for both transistors at the saturation state and back‐off regions. Side by side with the aid of the properly designed post‐matching tuned network (PMTN), these harmonic loading conditions make both amplifiers to operate in continuous Class‐F modes with enhanced‐added efficiencies over wideband conditions. As a result, a succession of highly efficient DPA modes can be formed over a continuous frequency range in the full Doherty region, resulting in a reduced‐size enhanced power efficiency wideband DPA. For verification, a wideband DPA operating from 1.1 to 1.8 GHz was designed and implemented using the proposed topology. The measured drain efficiency of the implemented DPA at 6‐dB back‐off is 52.5%–67.5%, while the saturated power across the specified bandwidth is 43–43.7 dBm. The fabricated DPA exhibits an average efficiency of 48.7%–59.4%, when supplied by a 40‐MHz long‐term evolution (LTE) signal with a 7.5‐dB peak‐to‐average power ratio (PAPR). Performing digital pre‐distortion (DPD) improves the adjacent channel power ratio (ACLR) from −25.8 dBc to −47.6 dBc.

Xy = cos (x + y) and other implicit equations that are surprisingly easy to plot

The following equations relate y only implicitly to x:(1)(2) In both equations, y is a function of x for a continuous range of (x, y) values in the real x-y plane. (1) represents an ellipse. (2) has been designed by the author to have a solution in the real x-y plane at (−1, 2), and because the function on the left-hand side of (2) meets certain conditions regarding continuity and partial differentiability there must be a line of points in the real x-y plane satisfying (2) and passing continuously through (−1, 2) [1, pp. 23-28].

Gridless compressed covariance sensing for parameter identification of nonuniform and undersampled blade tip timing data

Due to the harsh working environments, rotating blades are susceptible to failures, which endanger the operational safety of turbomachinery; thus, it is important to monitor rotating blades to promptly detect incipient failure. Blade tip timing (BTT) is a promising approach for monitoring the health of rotating blades owing to its noncontact nature, high measurement efficiency, and long service life. However, the large gap between the high vibration frequency and low sampling frequency results in severe undersampling of the BTT signal. Although advanced methods have been proposed to reconstruct the spectrum or identify parameters from BTT signal, almost all of them face basis mismatch issue caused by frequency discretization and suffers from inevitable reconstruction errors. To overcome these limitations, we developed a gridless compressed covariance sensing (GCCS) approach for the sparse spectral estimation and parameter identification of BTT data. Unlike existing methods relying on frequency discretization, GCCS directly performs a continuous range of spectrum reconstruction and parameter estimation. We derived that GCCS is equivalent to a weighted atomic norm minimization (ANM) with the weight function linked to the Capon spectrum, which implies the advantages of GCCS over methods based on conventional ANM. GCCS involves two core steps, first, covariance (matrix) recovery from compressive samples is formulated as a semidefinite programming; second, the extended Prony’s method is employed as a postprocessing technique to retrieve vibration parameters from the covariance estimations, thereby achieving continuous parameter estimation. The quantitative comparison in the simulations and experiments shows the effectiveness of GCCS in overcoming basis mismatch and improving the accuracy and consistency of the parameter estimation.

A comparative study of two presbyopia-correcting intraocular lenses combining bifocal and extended depth-of-focus profiles.

To compare the visual performance of two presbyopia-correcting intraocular lenses (IOLs) that combine both bifocal and extended depth-of-focus profiles, Artis® Symbiose® Plus (Symbiose Plus; Cristalens Industrie, Lannion, France) and Tecnis® Synergy® (Synergy; Johnson & Johnson Vision, Santa Ana, CA, USA). The medical records of patients with cataract bilaterally implanted with either Symbiose Plus or Synergy between January 2022 and January 2023 were assessed. The principal measures of postoperative findings included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), uncorrected intermediate visual acuity (UIVA), uncorrected near (40 and 33cm) visual acuity (UNVA), objective optical quality (OOQ) parameters, distance-corrected defocus curve analysis, and surveys of subjective satisfaction. Total of 96 eyes from 48 patients were enrolled. Each group was equally composed of 24 patients, 48 eyes. There were no significant differences between the two groups on baseline characteristics. Both IOLs displayed excellent binocular UDVA, CDVA, and UNVA (40 and 33cm) with no statistical difference (p = 0.467(UDVA), p = 0.584(CDVA), p = 0.096(40-cm UNVA), and p = 0.621(33-cm UNVA)). However, with regard to UIVA, the Synergy group showed significantly superior results (p < 0.001). In contrast, the Symbiose Plus group showed significantly better results on OOQ parameters and patient-reported quality of vision survey outcomes (both p < 0.001). Both IOLs provided a decent continuous range of vision from near to far distance.

A novel 4 × 4 butler matrix with continuously tunable phase covering 360° range and application for 1‐D and 2‐D beam scanning array

AbstractA novel 4 × 4 Butler Matrix (BM) with continuously tunable phase covering phase range from −180° to 180° is proposed using substrate integrated waveguide technology. The proposed BM consists of two H‐plane hybrid couplers, two E‐plane hybrid couplers and four 180° tunable phase shifters. With this simple configuration, the proposed BM can realise a continuously tunable progressive phase difference from −180° to 180° in a one‐dimensional (1‐D) or two‐dimensional (2‐D) form. For demonstration, the proposed BM has been fabricated to feed a 1 × 4 or 2 × 2 broadband microstrip antenna arrays. The fabricated prototype has a 16.7% fractional impendence bandwidth centred at 6 GHz. The measured pattern for the 1‐D array showed a continuous beam scanning range from −39° to 39° in H‐Plane, while the measured radiation patterns for the 2‐D array showed continuous beam range from −27° to 30° in elevation and 0°–180° in azimuth. The measurement results were in good agreement with the simulation results.

Advanced age predicts increased susceptibility to attribute, goal, and risky-choice framing in negative frame valences

The framing effect has been extensively studied in the context of attribute, goal, and risky-choice framing, revealing its significant impact on decision-making. However, the interplay between age and the framing effect remains relatively unexplored, and existing findings are inconclusive and conflicting. Addressing this gap, this study investigates the influence of age on all three types of framing using a large cohort of participants (N = 696). The Johnson-Neyman technique was employed to examine the effect across a continuous range of ages. The analysis demonstrated that advanced age significantly increased susceptibility to the framing effect. Moreover, it was found that this susceptibility primarily manifests in response to negative frames across all framing types. These findings not only align with the socioemotional selectivity theory and dual-process model but also underscore the importance of affect heuristics in decision-making among older adults. By offering a robust examination of all three types of framing and their interactions with age, this study provides a theoretical foundation for the role of age as a potential moderator in framing contexts. These findings may therefore inform the development of targeted strategies to mitigate the impact of the framing effect on elderly populations.