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Using machine learning algorithms to predict MACE in peritoneal dialysis patients
A parallel magnetic tunnel junction-based probabilistic Ising processor for efficient quadratic optimization
Low-threshold single-mode lasing in high-quality all-inorganic CsPbCl3 perovskite microplates
All-inorganic lead halide perovskites (CsPbX3) have emerged as game-changing gain media for micro-lasers due to their facile synthesis, ultra-high photoluminescence quantum yield, and excellent spectral tunability. However, realizing high-quality, low-threshold, and geometrically simple single-mode blue lasing, essential for integration into next-generation photonic circuits, remains a substantial challenge. Here, we report the successful, low-cost synthesis of high-quality, single-crystalline CsPbCl3 microplates with remarkably smooth facets, functioning as natural whispering-gallery mode microcavities. The outstanding blue single-mode lasing performance under optical pumping has been demonstrated. The optimized CsPbCl3 microplates achieve a low lasing threshold of 5.68 μJ cm−2 and a high quality factor (Q) exceeding 2000. Crucially, the stable single-mode emission is realized through a synergistic mechanism: the enhanced free spectral range enabled by size-controlled microplates combined with the intrinsic self-absorption effect of CsPbCl3, which effectively suppresses mode competition and parasitic modes. Our work not only introduces a high-performance, blue-emitting laser platform based on simple CsPbCl3 microplates but also offers a general, lithography-free strategy for achieving robust single-mode output in all-inorganic perovskite micro-lasers.
Ultrasound-guided percutaneous electrolysis versus dry needling in patients with chronic low back pain a double-blind randomized clinical trial
Mad1 facilitates α5 integrin trafficking from the Golgi to promote abscission during cytokinesis
Direct red-detuned soliton generation via lower-power auxiliary laser assistance
Integrated soliton microcombs have emerged as a promising solution for applications in precision metrology, high-speed optical communications, and integrated photonics. In practical deployment of soliton microcombs, it is a challenge to generate stable solitons due to power-dependent resonance shifts caused by thermo-optic and Kerr effects. In this Letter, a direct red-detuned soliton generation method is proposed through backward tuning of the pump laser from the red-detuned side under lower-power auxiliary laser assistance. The auxiliary laser modifies intracavity Kerr dynamics, enabling the system to directly enter the soliton regime without encountering unstable power transitions. This method avoids the chaotic-to-soliton transitional state that typically occurs during forward tuning from the blue-detuned to the red-detuned side. Experimental results using silicon nitride microresonators show that backward tuning requires less than half the auxiliary laser power compared to forward tuning methods. Soliton is generated with the auxiliary laser power 1.46 dB lower than the pump laser under both lasers coupled into the same resonance mode. Note that the reduced auxiliary laser power in this method suppresses backscattering effects from the auxiliary-laser-generated comb, thereby preserves soliton spectral integrity. The proposed method provides a stable and power-efficient route to soliton generation for practical deployment of the soliton microcombs in compact and scalable photonic applications.
Effect of forming degree in rotary hammer forging
Abstract Rotary press forging (RPF) has been introduced in the last century. Despite its advantages, it produces defects in the forgings such as mushrooming, eccentricity, and twisting. Rotary hammer forging (RHF) is a new process invented by the author to reduce such defects. RHF is considered as a multi-axes compression forging process where the material is subjected to several repeated hammering blows to be deformed incrementally and partially, while the produced deformation zone is swept over the whole area of the workpiece. Previous works showed that the specimen geometry, the inclination angle and the rotational speed affect such defects as mushrooming effect, eccentricity and twisting angle, but they are less severe in RHF than RPF. The present work has studied the effect of the forming degree (FD) on the forgings produced by both RPF and RHF to compare between the two processes. Special set-ups have been used where a die is rotating while either a pressing head or hammering head is used to deform the specimen. Independent variable parameters were chosen such that the specimen geometry H/D = 1, the inclination angle = 4 $$^{\circ }$$ , the rotational speed N =260 rpm, number of blows per revolution in case of RHF = 1.2. The results showed that FD has its influence on the mushrooming effect, twisting angle, and eccentricity, although they are less in the case of RHF. RHF reduces the defects referred to RPF by 5 to 13% for the mushrooming effect, 0 to 33% for the eccentricity, and 70 to 80% for the twisting angle. Thus, RHF is advantageous than RPF.
A two-mode thermomechanically squeezed phonon laser
Simultaneous measurement of the Lorentzian and Gaussian linewidths of laser
Linewidth is a key parameter reflecting the coherence of single-frequency lasers. While the linewidth contributed by white noise has been widely studied, the effect of nonwhite noise, mainly flicker noise, is hard to evaluate. However, flicker noise can cause linewidth broadening much larger than the Lorentzian component. Considering that interference visibility can serve as an effective indicator of phase noise magnitude, in this work, we quantify flicker noise as Gaussian linewidth and analyze the relation between interference visibility and laser linewidth. We find that the logarithm of visibility depends quadratically on the delay: the linear term is due to white noise, and the quadratic term arises from flicker noise. Based on this finding, we propose a method to simultaneously measure Lorentzian and Gaussian linewidths. This approach not only avoids flicker noise interference in Lorentzian linewidth measurements but also provides a convenient way to assess the magnitude of flicker noise. In addition, this approach effectively reduces the dependence of the linewidth measurement experiment on the length of the delay fiber, with shorter fibers helping to minimize environmental disturbances. More importantly, the introduction of the Gaussian linewidth provides a more comprehensive characterization of the laser linewidth.
Application of the Kelvin-Voigt viscoelastic model to hippus reveals major insights into the autonomic nervous system activity
A multi-host mechanistic model of African swine fever emergence and control in Romania
Abstract The on-going African swine fever pandemic has been devastating to affected nations, with continued spread observed despite aggressive interventions. Suspected interspecific transmission among wild and domestic hosts further complicates control efforts, yet its role in epidemic propagation remains poorly understood. Here, we develop and calibrate a multi-host mechanistic transmission model to the first wave of the epidemic in Romania (June–December 2018), quantifying these dynamics and evaluating counterfactual management scenarios. We estimated that 60% (95% credible interval: 27–83%) of outbreak farms were linked to other outbreak farms, 27% (5.3–67%) to infected wild boar populations, and 13% (1.9–27%) to external sources. For wild boar, 39% (3.8–93%) of infected populations were estimated to have originated from outbreak farms, and 61% (7.3–96%) from other infected wild boar populations, with favorable habitat exhibiting higher susceptibility and infectivity than unfavorable habitat. Among alternative control strategies, reactive and preventive culling of domestic pig herds yielded the greatest decrease in median final epidemic size among domestic pigs. These findings provide quantitative evidence that interspecific transmission was a critical epidemic driver, and a necessary target for achieving holistic control. Our model offers a flexible, rapidly-deployable framework for informing surveillance and response policy in at-risk regions.
Development of high-thermal conductive Ag@diamond composite sintering paste and its application in power modules
Diamond, known for its exceptional thermal conductivity and low coefficient of thermal expansion, offers significant advantages as a filler in composite solder pastes for high-power electronic devices. This study investigates Ag@diamond composite sintering pastes with varying diamond doping concentrations (2%, 5%, 8%, and 10%). The Ag@5%diamond paste achieved the highest thermal conductivity of 96.59 W/m K, a 43.05% increase compared to undoped paste. The shear strength was highest for Ag@2%diamond at 92.25 MPa. However, at higher doping levels (8% and 10%), both thermal conductivity and shear strength decreased due to diamond particle agglomeration. Microstructural analysis showed that agglomeration weakened the bonding, leading to interfacial detachment during fracture. A finite element analysis-based silicon carbide chip packaging model demonstrated a 3.09 °C reduction in maximum junction temperature compared to the sintered pure Ag. These results suggest that Ag@diamond composite sintering pastes offer an optimal balance of high shear strength and enhanced thermal conductivity, making them promising for thermal management in high-power devices.
SLM-based PAPR reduction for improved performance of DCO-OFDM LiFi using blind estimation for healthcare monitoring system
Abstract The necessity for reliable healthcare monitoring following the COVID-19 pandemic has highlighted the limitations of RF-based devices in medical settings. Visible light communication (VLC), which provides inherent security and is resistant to RF interference, is a good alternative. This work proposes a VLC system using DC-biased optical (DCO) orthogonal frequency division multiplexing (OFDM) for resilient, high-speed biomedical data transmission through indoor optical fading channel. In this system, data is modulated using quadrature amplitude modulation (QAM) with order 4 and 16. Four equalization methods; block-type, comb-type, superimposed training (ST), and blind channel estimation (CE); are implemented across three patient positioning scenarios. We integrate blind channel estimation and SLM-based PAPR reduction for a dynamic healthcare LiFi scenario. A comprehensive comparative analysis of CE techniques is conducted under realistic patient positioning (LOS/NLOS) conditions. An analysis of the trade-off between spectral efficiency and energy-to-noise ratio is examined in this context. Simulation results reveal a high Peak-to-Average Power Ratio (PAPR), reaching 15 dB with block-type CE. To mitigate this, Selected Mapping (SLM) is applied with three complex phase sequences, and three real sequences, achieving up to 4 dB PAPR reduction with no Bit Error Rate (BER) degradation. At 28 dB SNR, BER values were $$10^{-2}$$ , $$3\times 10^{-2}$$ , $$4\times 10^{-2}$$ , and $$7\times 10^{-2}$$ for blind, block-type, comb-type, and ST CE, respectively. Spectral efficiency declines with increased multipath, yet blind CE maintains the highest performance, reaching 0.9 bits/s/Hz with 20 multipath components. Additionally, complex phase vectors in SLM provide an extra 1 dB PAPR gain over real-valued versions.
Lipidomic analyses of large cohort studies define the role of lipid metabolism in bridging diet and cardio-metabolic health
Stress-induced efficiency degradation mechanism of InGaN-based red micro-LEDs depending on their size
This study systematically investigates the influence of forward current-induced stress on the optoelectronic performance of InGaN/GaN-based red micro light-emitting diodes with pixel sizes of 20 × 20 and 40 × 40 μm2. A constant forward current density of 3 A/cm2 was applied for 420 min. After aging, the 20-μm device exhibits a pronounced reduction in external quantum efficiency (EQE) by 43.2%, whereas the 40-μm device showed only a 16.5% decrease. Micro-photoluminescence mapping reveals that point defect formation near the mesa sidewalls is more prominent in the smaller device. Moreover, the degradation of peak emission intensity was more severe near the sidewall than in the center region after aging, which is more significant in the 20-μm device. This degradation is attributed to carrier tunneling through defect states generated during prolonged operation. Consequently, the pronounced EQE degradation observed in smaller devices is primarily ascribed to defect-assisted carrier tunneling. Additionally, this study elucidates the origin of the shorter peak emission wavelength observed near the mesa sidewall compared to that at the center region, which arises from strain relaxation.
Driven by motivation, fueled by rage, and struggling to disengage: a serial mediation model of internet gaming disorder in adolescents
Selective solar wax refining with nanoscale zero-valent iron
Abstract Wax refining transforms raw wax into high-grade product by increasing the uniformity of molecular carbon-chain length and removing impurities. Conventional thermochemical approaches face inherent limitations in effectively reducing carbon-chain dispersity ( Ð ) due to their non-selective C-C scission in feedstock waxes. This mechanistic constraint consequently necessitates energy-intensive downstream processing involving fractional distillation and purification. Here, we demonstrate a selective solar wax refining method that upgrades the raw polyethylene wax by significantly reducing its Ð from 2.5 to 2.0 in one step with a reaction selectivity beyond 80%, enabled by nanoscale zero-valent iron (nZVI) catalyst and sunlight. At the nZVI-wax interface, photons activate C-H bonds to provide hydrogen atoms, while localized hot spots mediate C-C bonds cleavage via hydrogen atom transfer initiated hydrocracking and concurrent evaporative desorption of fragmented wax product, thereby achieving precise control over carbon-chain dispersity. This work exemplifies the potential in precise and efficient solar refinery.
Improved electro-actuation performance of polyurethane-based dielectric elastomer under ultra-low electric fields via introducing soft functional filler
Dielectric elastomers (DEs) show promise in applications such as soft robots, artificial muscles, and sensors due to their large actuation strain and high energy density. However, such large actuation strains in DEs are typically achieved under relatively high driving electric fields, which limits their practical applications, particularly in biomedicine and healthcare fields. Consequently, obtaining excellent electro-actuated strain under ultra-low electric fields is a significant challenge for DEs. Herein, an acrylate-based copolymer (defined as C-PEG) was introduced into the thermoplastic polyurethane (TPU) matrix as a soft filler. The intermolecular hydrogen-bonding interactions between C-PEG and the TPU matrix can weaken the hydrogen-bonded cross-linking network of TPU, thereby reducing the Young's modulus of the composites. Furthermore, the inherent polar groups of C-PEG and the hydrogen-bonding interactions between C-PEG and TPU can further enhance the polarization ability of the composites. The results show that the C-PEG/TPU composite achieves an actuation strain of 10.8% under ultra-low electric fields (10 V/μm), which is 468.9% higher than that of pure TPU. Therefore, this study presents a promising approach for fabricating novel DEs with superior electro-actuated properties under ultra-low electric fields.
Energy, environment, and economy implications of electrifying minibus taxis in African cities
Abstract The electrification of minibus taxis in Africa is envisioned to play an important role in decarbonising transportation, reducing urban air pollution, and generating economic savings. However, comprehensive quantifications of these implications are scarce. This study introduces a modelling approach based on readily available data to simulate minibus operation and evaluate the key energy, environmental, and economic implications of such an electrification. Applying our model to nine diverse African cities, we find that electrifying minibuses could prevent the emission of 4.3 to 19.2 tCO $$_2$$ annually per vehicle, based on current electricity mixes, while saving minibus owner-operators US$1.2k to US$14.0k in annual fuel costs. Using a relative exposure index for minibus-related air pollution, we also identify that approximately 23 million people across these cities could benefit from improved air quality. Nevertheless, substantial variations in the charging demand–both per vehicle and aggregated per city–are observed, emphasising the critical importance of energy planning and tailored electrification strategies. This research provides insights for policymakers and planners, and offers a transparent and replicable framework for assessing the impacts of public transport electrification across diverse locations.