Browse Articles

Examining isotonic and isometric exercises for post-activation performance enhancement in kickboxers upper limb strength and power

Tunable interfacial Rashba spin–orbit coupling in asymmetric AlxIn1−xSb/InSb/CdTe quantum well heterostructures

We report the manipulation of the Rashba-type spin–orbit coupling (SOC) in molecular beam epitaxy-grown AlxIn1−xSb/InSb/CdTe quantum well heterostructures. The effective band bending warrants a robust two-dimensional quantum confinement effect, and the unidirectional built-in electric field arisen from the asymmetric hetero-interfaces leads to a pronounced Rashba SOC strength. By tuning the Al concentration in the top AlxIn1−xSb barrier layer, the optimal structure of x = 0.15 exhibits the largest Rashba coefficient of 0.23 eV Å as well as the highest low-temperature electron mobility of 4400 cm2 · V−1 · s−1. Moreover, quantitative investigations of the weak anti-localization effect further justify the prevailing D'yakonov–Perel spin relaxation mechanism during the charge-to-spin conversion process. Our results underscore the importance of quantum well engineering in shaping the magneto-resistance responses, and the narrow bandgap semiconductor-based heterostructures may serve as a reliable framework for designing energy-efficient spintronic applications.

Sucker rod straightness measurement method based on probability statistics of edge point detection

Dielectric reliability and interface trap characterization in MOCVD grown <i>in situ</i> Al2O3 on β-Ga2O3

In this article, we investigate the in situ growth of Al2O3 on β-Ga2O3 using metal-organic chemical vapor deposition at a high temperature of 800 °C. The Al2O3 is grown within the same reactor as the β-Ga2O3, employing trimethylaluminum and O2 as precursors without breaking the vacuum. We characterize the shallow and deep-level traps through stressed capacitance–voltage (C–V) and photo-assisted C–V methods. The high-temperature deposited dielectric demonstrates an impressive catastrophic breakdown field of approximately 10 MV/cm. Furthermore, we evaluate the reliability and lifetime of the dielectrics using time-dependent dielectric breakdown measurements. By modifying the dielectric deposition process to include a high-temperature (800 °C) thin interfacial layer and a low-temperature (600 °C) bulk layer, we report a 10-year lifetime under a stress field of 3.5 MV/cm along a catastrophic breakdown field of 7.8 MV/cm.

Use of inpatient palliative care in metastatic testicular cancer patients undergoing critical care therapy: insights from the national inpatient sample

AbstractTo test for rates of inpatient palliative care (IPC) in metastatic testicular cancer patients receiving critical care therapy (CCT). Within the Nationwide Inpatient Sample (NIS) database (2008–2019), we tabulated IPC rates in metastatic testicular cancer patients receiving CCT, namely invasive mechanical ventilation (IMV), percutaneous endoscopic gastrostomy tube (PEG), dialysis for acute kidney failure (AKF), total parenteral nutrition (TPN) or tracheostomy. Univariable and multivariable logistic regression models addressing IPC were fitted. Of 420 metastatic testicular cancer patients undergoing CCT, 70 (17%) received IPC. Between 2008 and 2019, the rates of IPC among metastatic testicular cancer patients undergoing CCT increased from 5 to 19%, with the highest rate of 30% in 2018 (EAPC: + 9.5%; 95% CI + 4.7 to + 15.2%; p = 0.005). IPC patients were older (35 vs. 31 years, p = 0.01), more frequently had do not resuscitate (DNR) status (34 vs. 4%, p &lt; 0.001), more frequently exhibited brain metastases (29 vs. 17%, p = 0.03), were more frequently treated with IMV (76 vs. 53%, p &lt; 0.001) and exhibited higher rate of inpatient mortality (74 vs. 29%, p &lt; 0.001). In multivariable analyses, DNR status (OR 10.23, p &lt; 0.001) and African American race/ethnicity (OR 4.69, p = 0.003) were identified as independent predictors of higher IPC use. We observed a significant increase in rates of IPC use in metastatic testicular cancer patients receiving CCT, rising from 5 to 19% between 2008 and 2019. However, this rates remain lower compared to metastatic lung cancer patients, indicating the need for further awareness among clinicians treating metastatic testicular cancer. The increase in IPC rates for metastatic testicular cancer patients receiving CCT indicates a need for ongoing education and awareness among healthcare providers. This could enhance the integration of IPC in the treatment of advanced cancer, potentially improving quality of life and care outcomes for survivors.

Flexible 3ω sensors on submicron-thick parylene substrates for thermal conductivity measurements of liquids and soft materials

Measurement of thermal conductivity in liquids and soft materials is pivotal across various sectors, from designing cooling systems for electronic devices to monitoring biological parameters via medical devices and studying the thermal properties of tissues. Accurate thermal conductivity measurements require high sensitivity, and a flexible measurement device is advantageous to adapt to the shape of the sample. The 3ω method stands out as an ideal technique that meets these criteria, offering a simple and sensitive approach to assess the thermal properties of materials. In this study, we introduce a 3ω sensor fabricated on submicron-thick parylene substrates. The parylene substrate not only provides the necessary flexibility but also acts as an insulating layer, essential for the measurement of conductive materials. The sensor's sensitivity was enhanced by reducing the thickness of the parylene substrate. A thermal peeling film was utilized as a supporting substrate during the fabrication of the 3ω sensor with a thin parylene substrate, which has a thickness of 0.77 μm. The performance of the sensor was evaluated by measuring the thermal conductivities of water, isopropyl alcohol, and their mixtures, achieving results within 15% of previously reported values.

Retraction Note: Fabrication of a magnetic alginate-silk fibroin hydrogel, containing halloysite nanotubes as a novel nanocomposite for biological and hyperthermia applications

Structural and electrical properties of fiber textured and epitaxial molybdenum thin films prepared by magnetron sputter epitaxy

Molybdenum (Mo) due to its optimal structural, physical, and acoustic properties finds application as electrode material in aluminum scandium nitride and aluminum nitride (AlN) based bulk acoustic wave (BAW) resonators. Epitaxial Mo thin films exhibiting low resistivity can improve the performance of the BAW resonator by enhancing both the electro-mechanical coupling coefficient (keff2) and quality factor Q. In this study, we systematically vary the growth temperature of Mo grown on fiber-textured and epitaxial wurtzite-aluminum nitride (AlN) to study the changes in structural and electrical properties of the Mo films. Results show that Mo grown at 700 °C on epitaxial AlN exhibits low surface roughness (Rq = 0.8 nm), large average grain diameter (dgrain = 330 nm), low resistivity (ρ=6.6 ± 0.06  μΩ cm), and high crystal quality (XRD Mo 110 ω-FWHM = 0.63°). XRD pole figure and ϕ-scan analysis reveal that irrespective of the growth temperature, Mo is fiber textured on fiber-textured AlN and has three rotational domains on epitaxial AlN. This study shows that the resistivity of Mo reduces with increasing growth temperature, which we relate to increasing average grain diameter. Additionally, we show that fiber-textured Mo has more high angle grain boundaries resulting in consistently higher resistivity than its epitaxial equivalent.

Prognostic implications of system inflammation response index in atrial fibrillation patients with type 2 diabetes mellitus

Coupling of photoluminescence and flexoelectricity in all-inorganic flexible transparent heterojunctions induced by mechanical strain

Flexible and transparent optoelectronic technology has shown great application prospects in various fields. Introducing rare earth luminescent centers into inorganic ferroelectric systems can benefit the electrical properties by utilizing the polar nanodomains brought about by rare earth doping and also facilitate the investigation of coupling effect between luminescence modulation and flexoelectric effect. This article studies Pr3+-doped barium titanate all-inorganic flexible transparent heterojunctions and explores the direct modulation of the fluorescence and flexoelectric response through mechanical strain stimulation. We aim to investigate the essential correlation and physical mechanism of strain-flexoelectricity-photoluminescence (force-electric-photon) coupling, providing an important basis for the dynamic balance regulation between radiative and non-radiative transitions. Therefore, this work will significantly promote the development of highly integrated flexible sensing and intelligent optoelectronic devices.

An analysis of extraskeletal osteosarcoma based on the literature

Reliability of NiO/β-Ga2O3 bipolar heterojunction

Ultra-wide bandgap (UWBG) NiO/β-Ga2O3 p–n junction has recently emerged as a key building block for emerging electronic and optoelectronic devices. However, the long-term reliability of this bipolar junction remains elusive. Here, the temporal evolution of the transient parametric shift is characterized in this junction under the prolonged forward- and reverse-bias stresses as well as in the post-stress recoveries. The temperature-dependent evolutions reveal the energy level and time constant of the dominant trap. The forward-bias stress is found to induce a negative turn-on voltage (VON) shift, the magnitude of which correlates with the stressed current density, while the reverse-bias stress leads to the opposite effect. Such VON shift is induced by an electron trap with an activation energy of 0.46 eV, which may originate from native point defects in β-Ga2O3 near the junction interface. Under a high forward current stress of 1000 A/cm2, device failure is found to be located at the edge region with the thinnest NiO, which is likely to be caused by the injection of hot electrons that diffuse across the entire NiO layer. Overall, the magnitude of parametric shift is approaching or comparable to those reported in the native SiC and GaN p–n junctions, suggesting that the NiO/β-Ga2O3-based UWBG devices have good potential to achieve a reliability comparable to their WBG counterparts.

Rapid CO2 mineralization by zeolite via cation exchange

Giant electrostriction in textured La2Ce2O7 ceramics: A promising lead-free alternative for electromechanical conversion

The search for high-performance, lead-free materials with tailored electromechanical properties is crucial for the advancement of energy harvesting and actuator technologies. While piezoelectric materials offer promising solutions, balancing high piezoelectric response with low dielectric permittivity remains a significant challenge. Recent research has highlighted the potential of “giant” electrostriction as an alternative approach, offering substantial electromechanical responses with more favorable electrical properties. This work investigates the electrostrictive and dielectric properties of non-textured and textured La2Ce2O7 ceramics. Our findings reveal a substantial electrostrictive coefficient [M33 ≈ 10−18 (m/V)2, exceeding conventional electrostrictive materials], coupled with a high effective piezoelectric response (d33eff = 40 pm/V at E = 100 kV/cm) and a high effective piezoelectric voltage coefficient (g33eff = 146–205 × 10−3 Vm/N). Notably, [111]-texturing of La2Ce2O7 significantly reduces dielectric losses, further enhancing its suitability for energy harvesting and actuator applications. The combination of electromechanical and dielectric properties creates conditions for high energy-harvesting performance, comparable to lead-containing ceramics and far superior to lead-free alternatives. Combined with temperature stability and compatibility with Si-based microfabrication, La2Ce2O7 emerges as a promising lead-free alternative for high-performance electromechanical energy conversion applications.

Fast barrier-free switching in synthetic antiferromagnets

AbstractWe analytically solve the Landau-Lifshitz equations for the collective magnetization dynamics in a synthetic antiferromagnet (SAF) nanoparticle and uncover a regime of barrier-free switching under a short small-amplitude magnetic field pulse applied perpendicular to the SAF plane. We give examples of specific implementations for forming such low-power and ultra-fast switching pulses. For fully optical, resonant, barrier-free SAF switching we estimate the power per write operation to be $$ \sim 100 $$ ∼ 100  pJ, 10–100 times smaller than for conventional quasi-static rotation, which should be attractive for memory applications.

<i>In situ</i> determination of the optical axis orientation in a single grain using time-domain Brillouin microscopy

In this paper, we develop a method that combines optical birefringence properties and time-domain Brillouin scattering microscopy to determine in situ the optical axis orientation of each single micrometer size grain in a polycrystalline sample. We illustrate the method by investigating the room temperature multiferroic material BiFeO3 where the optical axis coincides with the ferroelectric polarization direction. We are able to find the grain orientation and also provide the sound velocity (longitudinal and transverse) since the method is based on the Brillouin scattering process. These advances open interesting perspectives for probing the anisotropy of a micrometer size grain with an extension to the evaluation of the ferroelastic domain orientation in a non-contact and non-destructive manner.

An intelligent incentive-based demand response program for exhaustive environment constrained techno-economic analysis of microgrid system

AbstractThe cost-effective scheduling of distributed energy resources through sophisticated optimization algorithms is the main focus of recent work on microgrid energy management. In order to improve load factor and efficiency, load-shifting techniques are frequently used in conjunction with additional complex constraints such as PHEV scheduling and battery life assessment. Pollutant reduction, however, is rarely highlighted as a primary goal. An incentive-based demand response (IBDR) is introduced in the proposed work to close this gap and promote load curtailment during peak hours. IBDR policy rewards participant customers with incentives for load curtailment which in turn lowers emissions and generation costs. Furthermore, a trade-off approach ensures both environmental and economic sustainability by striking a balance between cost reduction and emission reduction. Considering the fact in view that the 30–40% of the microgrid customers are willing to participate in the IBDR program, six different scenarios that have been analysed, each of which involves various levels of grid participation and different approaches to pricing in the electricity market. These scenarios also include the implementation of demand response programmes. Differential evolution algorithm was used as the optimization tool for the study. The results achieved for all the scenarios demonstrate the suitability and effectiveness of implementing the suggested IBDR strategy in terms of cost savings. According to numerical results reported, the generating cost decreased by 10–13% with the inclusion of IBDR. Additionally, a 6–8% reduction in peak and 4–5% improvement in load factor was also realised as a positive impact of the IBDR policy. The weighted economic emission dispatch algorithm offered a balanced solution that considered both the minimum generation cost and emissions for various load models in the microgrid system.

450 nm light-induced upconversion ultraviolet-C photons for optical information encryption and sterilization

Ultraviolet-C (UVC) photons play a key role in many fields such as covert communication, bacterial inactivation, information storage, and encryption. Because the UVC component of solar spectrum is almost absorbed by the ozone layer around our earth, there is little natural UVC light on the earth. Therefore, developing artificial UVC light source is of great significance. The visible-to-UVC upconversion mechanism has been demonstrated to be a useful strategy. Here, we introduce a visible-to-UVC upconversion system, that is, CaSrSiO4:Pr3+. Under excitation of both commonly used laser and light-emitting diode at 450 nm, CaSrSiO4:Pr3+ emits UVC photons. The presence of UVC light of CaSrSiO4:Pr3+ has also been confirmed by a solar blind camera, in addition to an optical spectrometer. Moreover, experimental results show that the UVC emission of CaSrSiO4:Pr3+ is assigned to a two-photon assisted upconversion mechanism. In the end, we demonstrate the potential applications of CaSrSiO4:Pr3+ for information encryption and sterilization.

Differential physiological and yield responses of selected mung bean (Vigna radiata (L.) R. Wilczek) genotypes to various high-temperature stress regimes

Synaptic transistor based on reversible hydrogenation of graphene channel

Graphene transistors with a gate-controlled transition of neuromorphic functions between artificial neurons and synapses have attracted increasing attention because the atomic thickness could be easily modulated by different stimuli, which is very beneficial for synaptic applications. As a modulation method, a graphene electrolyte-gated transistor (EGT) has been proposed, in which the electrical conductance of the graphene channel is modulated by reversible electrochemical hydrogenation of graphene. However, only a sparse physically realized graphene-based synaptic H+-EGTs have been reported due to the difficulty of achieving a high concentration of protons at the electrolyte–graphene interface. Here, we have reported the H+-EGTs with a highly defective graphene channel and a gel electrolyte [H3PO4/poly(vinyl alcohol)], which is based on hydrogenation and dehydrogenation of highly defected-graphene, performing the similar functions as the common artificial synaptic transistors, with good retention (&amp;lt;1% attenuation per minute), analog tunability (&amp;gt;200 nonvolatile states), and precisely controllable resistance (∼0.4% step flipped per synaptic event). In addition, the cyclic voltammetry test was applied to confirm the hydrogenation and dehydrogenation of the graphene channel. It is expected that this principle can provide ideas for designing graphene-based artificial synapses enabling integrated functions of in-memory computing and in-memory sensing for the neuromorphic system.