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Antimicrobial susceptibility testing (AST) plays a critical role in assessing the resistance of individual microbial isolates and determining appropriate antimicrobial therapeutics in a timely manner. However, conventional AST normally takes up to 72 h for obtaining the results. In healthcare facilities, the global distribution of vancomycin-resistant Enterococcus fecium (VRE) infections underscores the importance of rapidly determining VRE isolates. Here, we developed an integrated antimicrobial resistance (AMR) screening strategy by combining matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) with machine learning to rapidly predict VRE from clinical samples. Over 400 VRE and vancomycin-susceptible E. faecium (VSE) isolates were analyzed using MALDI-MS at different culture times, and a comprehensive dataset comprising 2388 mass spectra was generated. Algorithms including the support vector machine (SVM), SVM with L1-norm, logistic regression, and multilayer perceptron (MLP) were utilized to train the classification model. Validation on a panel of clinical samples (external patients) resulted in a prediction accuracy of 78.07%, 80.26%, 78.95%, and 80.54% for each algorithm, respectively, all with an AUROC above 0.80. Furthermore, a total of 33 mass regions were recognized as influential features and elucidated, contributing to the differences between VRE and VSE through the Shapley value and accuracy, while tandem mass spectrometry was employed to identify the specific peaks among them. Certain ribosomal proteins, such as A0A133N352 and R2Q455, were tentatively identified. Overall, the integration of machine learning with MALDI-MS has enabled the rapid determination of bacterial antibiotic resistance, greatly expediting the usage of appropriate antibiotics.
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Antibacterianos , Aprendizaje Automático , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Humanos , Antibacterianos/farmacología , Antibacterianos/análisis , Pruebas de Sensibilidad Microbiana , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/aislamiento & purificación , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Enterococos Resistentes a la Vancomicina/aislamiento & purificación , Máquina de Vectores de Soporte , Farmacorresistencia BacterianaRESUMEN
The assembly and patterning engineering in two-dimensional (2D) materials hold importance for chip-level designs incorporating multifunctional detectors. At present, the patterning and stacking methods of 2D materials inevitably introduce impurity instability and functional limitations. Here, the space-confined chemical vapor deposition method is employed to achieve state-of-the-art kirigami structures of self-assembled WS2, featuring various layer combinations and stacking configurations. With this technique as a foundation, the WS2 nano-kirigami is integrated with metasurface design, achieving a photodetector with bidirectional polarization-sensitive detection capability in the infrared spectrum. Nano-kirigami can eliminate some of the uncontrollable factors in the processing of 2D material devices, providing a freely designed platform for chip-level multifunctional detection across multiple modules.
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BACKGROUND: Mitochondrial proteins assume a pivotal role in the onset and progression of diverse diseases. Nonetheless, the causal interconnections with sensorineural hearing loss (SNHL) demand meticulous exploration. Mendelian randomization analysis is a method used in observational epidemiological studies to predict the relationship between exposure factors and outcomes using genetic variants as instrumental variables. In this study, we applied this analytical approach to two distinct samples to predict the causal impact of mitochondrial proteins on SNHL. METHODS: Two-sample Mendelian randomization analyses were executed to scrutinize the predicted associations between 63 mitochondrial proteins (nuclear-encoded) and SNHL, utilizing summary statistics derived from genome-wide association studies. Assessments of pleiotropy and heterogeneity were carried out to gauge the robustness of the obtained findings. RESULTS: Four mitochondrial proteins exhibited a suggestive causal relationship with the susceptibility to SNHL. Dihydrolipoamide dehydrogenase (DLD; OR = 0.9706, 95% CI = 0.9382-0.9953, p = 0.0230) was linked to a diminished risk of SNHL. Conversely, elevated levels of mitochondrial ribosomal protein L34 (MRPL34; OR = 1.0458, 95% CI = 1.0029-1.0906, p = 0.0362), single-pass membrane protein with aspartate-rich tail 1 (SMDT1; OR = 1.0619, 95% CI = 1.0142-1.1119, p = 0.0104), and superoxide dismutase 2 (SOD2; OR = 1.0323, 95% CI = 1.0020-1.0634, p = 0.0364) were associated with an elevated risk of SNHL. CONCLUSION: This research utilized Mendelian randomization analysis to predict the relationship between mitochondrial proteins and SNHL. It provides a potential viewpoint on the etiology and diagnosis.
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Hybrid improper ferroelectricity can effectively avoid the intrinsic chemical incompatibility of electronic mechanism for multiferroics. Perovskite superlattices, as theoretically proposed hybrid improper ferroelectrics with simple structure and high technological compatibility, are conducive to device integration and miniaturization, but the experimental realization remains elusive. Here, we report a strain-driven oxygen octahedral distortion strategy for hybrid improper ferroelectricity in La2NiMnO6/La2CoMnO6 double-perovskite superlattices. The epitaxial growth mode with mixed crystalline orientations maintains a large strain transfer distance more than 90 nm in the superlattice films with lattice mismatch less than 1%. Such epitaxial strain permits sustainable long-range modulation of oxygen octahedral rotation and tilting, thereby inducing and regulating hybrid improper ferroelectricity. A robust room-temperature ferroelectricity with remnant polarization of ~ 0.16 µC cm-2 and piezoelectric coefficient of 2.0 pm V-1 is obtained, and the density functional theory calculations and Landau-Ginsburg-Devonshire theory reveal the constitutive correlations between ferroelectricity, octahedral distortions, and strain. This work addresses the gap in experimental studies of hybrid improper ferroelectricity for perovskite superlattices and provides a promising research platform and idea for designing and exploring hybrid improper ferroelectricity.
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Nuclear spin polarization plays a crucial role in quantum information processing and quantum sensing. In this work, we demonstrate a robust and efficient method for nuclear spin polarization with boron vacancy (V_{B}^{-}) defects in hexagonal boron nitride (h-BN) using ground-state level anticrossing (GSLAC). We show that GSLAC-assisted nuclear polarization can be achieved with significantly lower laser power than excited-state level anticrossing, making the process experimentally more viable. Furthermore, we have demonstrated direct optical readout of nuclear spins for V_{B}^{-} in h-BN. Our findings suggest that GSLAC is a promising technique for the precise control and manipulation of nuclear spins in V_{B}^{-} defects in h-BN.
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Long-life interlayer excitons (IXs) in transition metal dichalcogenide (TMD) heterostructure are promising for realizing excitonic condensates at high temperatures. Critical to this objective is to separate the IX ground state (the lowest energy of IX state) emission from other states' emissions. Filtering the IX ground state is also essential in uncovering the dynamics of correlated excitonic states, such as the excitonic Mott insulator. Here, we show that the IX ground state in the WSe2/MoS2 heterobilayer can be separated from other states by its spatial profile. The emissions from different moiré IX modes are identified by their different energies and spatial distributions, which fits well with the rate-diffusion model for cascading emission. Our results show spatial filtering of the ground state mode and enrich the toolbox to realize correlated states at elevated temperatures.
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The ambient stability is one of the focal points for applications of 2D materials, especially for those well-known air-sensitive ones, such as black phosphorus (BP) and transitional metal telluride. Traditional methods of encapsulation, such as atomic layer deposition of oxides and heterogeneous integration of hexagonal boron nitride, can hardly avoid removal of encapsulation layer when the 2D materials are encapsulated for further device fabrication, which causes complexity and damage during the procedure. Here, a van der Waals encapsulation method that allows direct device fabrication without removal of encapsulation layer is introduced using Ga2O3 from liquid gallium. Taking advantage of the robust isolation ability against ambient environment of the dense native oxide of gallium, hundreds of times longer retention time of (opto)electronic properties of encapsulated BP and MoTe2 devices is realized than unencapsulated devices. Due to the ultrathin high-κ properties of Ga2O3, top-gated devices are directly fabricated with the encapsulation layer, simultaneously as a dielectric layer. This direct device fabrication is realized by selective etching of Ga2O3, leaving the encapsulated materials intact. Encapsulated 1T' MoTe2 exhibits high conductivity even after 150 days in ambient environment. This method is, therefore, highlighted as a promising and distinctive one compared with traditional passivation approaches.
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Moiré superlattices with a robust twist proximity effect in the low-dimensional regime can facilitate nanoscale thermoelectric devices. In pristine systems, the low efficiency and lack of proficient control of thermoelectric properties impede desirable advancements in the field of energy conversion. In the present study, we demonstrate remarkable macroscopic thermoelectric response as a consequence of microscopic band structure modulation via the twist proximity in an engineered CrI3/1T-MoS2 moiré superlattice. The local twist effect, which leads to the microscopic phenomena of electron localization, results in a comprehensive electronic structure modulation. Consequently, these local effects convolute the macroscopic thermoelectric effect. Additionally, flat bands and angle-dependent metallic to semiconducting transitions are observed at 10.89, 23.41, and 30° twist angles. We correlate the observed phenomenon with the augmented spin-charge transport and interconversion via the twist proximity effect in its semiconducting phase. The estimated ultralow electronic and lattice thermal conductivities further corroborate with the observed large figure of merit and Seebeck coefficient. The maximum values of the Seebeck coefficient and figure of merit are estimated to be â¼413 µV/K and â¼4.3 at 200 K for 30° under the constant time relaxation approach. The twist-endowed outstanding thermoelectric effect in moiré superlattices with band modulation unveils a distinctive approach to establish efficient thermoelectric devices.
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van der Waals heterojunctions based on transition-metal dichalcogenides (TMDs) offer advanced strategies for manipulating light-emitting and light-harvesting behaviors. A crucial factor determining the light-material interaction is in the band alignment at the heterojunction interface, particularly the distinctions between type-I and type-II alignments. However, altering the band alignment from one type to another without changing the constituent materials is exceptionally difficult. Here, utilizing Bi2O2Se with a thickness-dependent band gap as a bottom layer, we present an innovative strategy for engineering interfacial band configurations in WS2/Bi2O2Se heterojunctions. In particular, we achieve tuning of the band alignment from type-I (Bi2O2Se straddling WS2) to type-II and finally to type-I (WS2 straddling Bi2O2Se) by increasing the thickness of the Bi2O2Se bottom layer from monolayer to multilayer. We verified this band architecture conversion using steady-state and transient spectroscopy as well as density functional theory calculations. Using this material combination, we further design a sophisticated band architecture incorporating both type-I (WS2 straddles Bi2O2Se, fluorescence-quenched) and type-I (Bi2SeO5 straddles WS2, fluorescence-recovered) alignments in one sample through focused laser beam (FLB). By programming the FLB trajectory, we achieve a predesigned localized fluorescence micropattern on WS2 without changing its intrinsic atomic structure. This effective band architecture design strategy represents a significant leap forward in harnessing the potential of TMD heterojunctions for multifunctional photonic applications.
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Valleytronics, i.e., the manipulation of the valley degree of freedom, offers a promising path for energy-efficient electronics. One of the key milestones in this field is the room-temperature manipulation of the valley information in thick-layered material. Using scanning photocurrent microscopy, we achieve this milestone by observing a geometrically dependent circular photocurrent in a few-layer molybdenum disulfide (MoS2) under normal incidence. Such an observation shows that the system symmetry is lower than that of bulk MoS2 material, preserving the optical chirality-valley correspondence. Moreover, the circular photocurrent polarity can be reversed by applying electrical bias. We propose a model where the observed photocurrent results from the symmetry breaking and the built-in field at the electrode-sample interface. Our results show that the valley information is still retained even in thick-layered MoS2 at room temperature and opens up new opportunities for exploiting the valley index through interface engineering in multilayer valleytronics devices.
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Non-centrosymmetric topological material has attracted intense attention due to its superior characteristics as compared with the centrosymmetric one, although probing the local quantum geometry in non-centrosymmetric topological material remains challenging. The non-linear Hall (NLH) effect provides an ideal tool to investigate the local quantum geometry. Here, we report a non-centrosymmetric topological phase in ZrTe5, probed by using the NLH effect. The angle-resolved and temperature-dependent NLH measurement reveals the inversion and ab-plane mirror symmetries breaking at <30 K, consistently with our theoretical calculation. Our findings identify a new non-centrosymmetric phase of ZrTe5 and provide a platform to probe and control local quantum geometry via crystal symmetries.
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Acute promyelocytic leukemia (APL) stands out as a distinctive form of acute leukemia, exhibiting a higher occurrence of thrombotic events when contrasted with other leukemia subtypes. Since thrombosis is a relatively rare but unfavorable condition with poor prognostic implications, it is crucial to determine the risk factors for thrombotic events in APL(thrombosis in large venous or arterial from onset to differentiation therapy in 30d). We performed a retrospective study involving 950 APL patients between January 2000 and October 2022, from which 123 were excluded by younger than 16 years of age, 95 were excluded by incomplete data, and 6 were excluded by thrombosis related to CVC or PICC. A total of 23 APL patients with thrombosis for inclusion in our analysis were performed a 1:5 ratio matching based on sex (perfect match) and age (within 5 years) to patients without thrombosis. These patients were continuously monitored in the outpatient department over a period of 5 years. We meticulously examined clinical and laboratory data to pinpoint the risk factors related to thrombotic events in APL. Our primary clinical endpoints were all-cause mortality and achieving complete remission, while secondary clinical outcomes included APL relapse. Thrombotic events were observed in 2.4% (23/950) of APL patients. Compared to patients without thrombosis, patients with thrombosis had higher lactate dehydrogenase (LDH) [313 (223, 486) vs. 233 (188, 367) U/L, p = 0.020], higher indirect bilirubin [11.2 (7.4, 18.6) vs.8.3 (6.0, 10.7) umol/L, p = 0.004], higher creatinine [72 (62, 85) vs. 63 (54, 74) umol/L, p = 0.026], higher CD2 expression (65.2 vs. 15.2%, p < 0.001), higher CD15 expression (60.9 vs. 24.3%, p = 0.001), and PML/RARαisoforms (p < 0.001). Multivariate-logistic-regression analysis revealed several factors that were markedly related to thrombosis, including LDH (OR≈1.003, CIs≈1.000-1.006, p = 0.021), indirect bilirubin (OR≈1.084, CIs≈1.000-1.188, p = 0.043), CD2 expression positive (OR≈16.629, CIs≈4.001-62.832, p < 0.001), and CD15 expression positive (OR≈7.747, CIs≈2.005-29.941, p = 0.003). The S-type (OR≈0.012, CIs≈0.000-0.310, p = 0.008) and L-type (OR≈0.033, CIs≈0.002-0.609, p = 0.022) PML/RARα isoforms were negatively associated with thrombosis. Kaplan-Meier curves indicated that the survival rates were remarkably varied between APL patients with and without thrombosis (HR:21.34, p < 0.001). LDH and indirect bilirubin are variables significantly associated with thrombosis in APL, S-type and L-type PML/RARαisoforms exhibit a negative association with thrombotic events. The thrombotic events of APL can predict the subsequent survival of thrombosis. The findings of our study have the potential to facilitate early detection of thrombosis and enhance the prognosis for individuals with APL who develop thrombosis. Further validation of our findings will be essential through future prospective or multicenter studies.
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Leucemia Promielocítica Aguda , Trombosis , Humanos , Leucemia Promielocítica Aguda/sangre , Leucemia Promielocítica Aguda/complicaciones , Leucemia Promielocítica Aguda/mortalidad , Masculino , Factores de Riesgo , Femenino , Trombosis/etiología , Trombosis/sangre , Trombosis/mortalidad , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Análisis por Apareamiento , Adolescente , Adulto Joven , L-Lactato Deshidrogenasa/sangre , Anciano , Bilirrubina/sangre , Pronóstico , Inducción de RemisiónRESUMEN
Objectives: The present study was conducted to explore the performance of micronutrients in the prediction and prevention of coronavirus disease 2019 (COVID-19). Methods: This is an observational case-control study. 149 normal controls (NCs) and 214 COVID-19 patients were included in this study. Fat-soluble and water-soluble vitamins were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, and inorganic elements were detected by inductively coupled plasma-mass spectrometry (ICP-MS) analysis. A logistic regression model based on six micronutrients were constructed using DxAI platform. Results: Many micronutrients were dysregulated in COVID-19 compared to normal control (NC). 25-Hydroxyvitamin D3 [25(OH)D3], magnesium (Mg), copper (Cu), calcium (Ca) and vitamin B6 (pyridoxic acid, PA) were significantly independent risk factors for COVID-19. The logistic regression model consisted of 25(OH)D3, Mg, Cu, Ca, vitamin B5 (VB5) and PA was developed, and displayed a strong discriminative capability to differentiate COVID-19 patients from NC individuals [area under the receiver operating characteristic curve (AUROC) = 0.901]. In addition, the model had great predictive ability in discriminating mild/normal COVID-19 patients from NC individuals (AUROC = 0.883). Conclusions: Our study showed that micronutrients were associated with COVID-19, and our logistic regression model based on six micronutrients has potential in clinical management of COVID-19, and will be useful for prediction of COVID-19 and screening of high-risk population.
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RATIONALE AND OBJECTIVES: To evaluate the performance of deep learning (DL) in predicting different breast cancer molecular subtypes using DCE-MRI from two institutes. MATERIALS AND METHODS: This retrospective study included 366 breast cancer patients from two institutes, divided into training (nâ¯=â¯292), validation (nâ¯=â¯49) and testing (nâ¯=â¯25) sets. We first transformed the public DCE-MRI appearance to ours to alleviate small-data-size and class-imbalance issues. Second, we developed a multi-branch convolutional-neural-network (MBCNN) to perform molecular subtype prediction. Third, we assessed the MBCNN with different regions of interest (ROIs) and fusion strategies, and compared it to previous DL models. Area under the curve (AUC) and accuracy (ACC) were used to assess different models. Delong-test was used for the comparison of different groups. RESULTS: MBCNN achieved the optimal performance under intermediate fusion and ROI size of 80 pixels with appearance transformation. It outperformed CNN and convolutional long-short-term-memory (CLSTM) in predicting luminal B, HER2-enriched and TN subtypes, but without demonstrating statistical significance except against CNN in TN subtypes, with testing AUCs of 0.8182 vs. [0.7208, 0.7922] (p=0.44, 0.80), 0.8500 vs. [0.7300, 0.8200] (p=0.36, 0.70) and 0.8900 vs. [0.7600, 0.8300] (p=0.03, 0.63), respectively. When predicting luminal A, MBCNN outperformed CNN with AUCs of 0.8571 vs. 0.7619 (p=0.08) without achieving statistical significance, and is comparable to CLSTM. For four-subtype prediction, MBCNN achieved an ACC of 0.64, better than CNN and CLSTM models with ACCs of 0.48 and 0.52, respectively. CONCLUSION: Developed DL model with the feature extraction and fusion of DCE-MRI from two institutes enabled preoperative prediction of breast cancer molecular subtypes with high diagnostic performance.
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We introduce MolPhase, an advanced algorithm for predicting protein phase separation (PS) behavior that improves accuracy and reliability by utilizing diverse physicochemical features and extensive experimental datasets. MolPhase applies a user-friendly interface to compare distinct biophysical features side-by-side along protein sequences. By additional comparison with structural predictions, MolPhase enables efficient predictions of new phase-separating proteins and guides hypothesis generation and experimental design. Key contributing factors underlying MolPhase include electrostatic pi-interactions, disorder, and prion-like domains. As an example, MolPhase finds that phytobacterial type III effectors (T3Es) are highly prone to homotypic PS, which was experimentally validated in vitro biochemically and in vivo in plants, mimicking their injection and accumulation in the host during microbial infection. The physicochemical characteristics of T3Es dictate their patterns of association for multivalent interactions, influencing the material properties of phase-separating droplets based on the surrounding microenvironment in vivo or in vitro. Robust integration of MolPhase's effective prediction and experimental validation exhibit the potential to evaluate and explore how biomolecule PS functions in biological systems.
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Algoritmos , Separación de Fases , Proteínas de Plantas , Proteínas Bacterianas/química , Sistemas de Secreción Tipo III/química , Proteínas de Plantas/químicaRESUMEN
Low-dimensional materials with prominent thermoelectric (TE) effect play a pivotal role in realizing state-of-the-art nanoscale TE devices. The fusion of TE effect with the magnetism through seamless integration of TE and magnetic materials in the 2D limit offers access to control longitudinal as well as transverse TE properties via magnetic proximity effect. Herein, we design a van der Waals (vdW) heterostructure of metallic 1T-MoS2with promising TE properties and a layer-dependent magnetic CrI3material. The result highlights exotic electronic and magnetic configurations of the designed monolayer-CrI3/1T-MoS2vdW heterostructure, which show magnetically-coupled TE characteristics. The observed remarkable magnetic proximity stems from large magnetic anisotropy energy and spin polarization, which are found to be 2.21 meV Cr-1and 12.30%, respectively. To this end, the semiconducting CrI3layer with intrinsic magnetism leads to efficient control and tunability of the observed spin-correlated anomalous Nernst effect. Moreover, a large dimensionless figure of merit of â¼6 and a power factor ofâ¼3.8×1011/τ∘ Wm-1K-2s-1near the Fermi level at 300 K endorse the rejuvenated TE effect. The strong relativistic spin-orbit coupling validates the significant correlation of TE properties with intrinsic magnetic configuration. The present study underscores the significance of the magnetic proximity-governed TE effect in vdW heterostructures to engineer low-dimensional TE devices.
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RATIONALE AND OBJECTIVES: To compare the differences in apparent diffusion coefficient (ADC) and synthetic magnetic resonance (MR) measurements of four region of interest (ROI) placement methods for breast tumor and to investigate their diagnostic performance. METHODS: 110 (70 malignant, 40 benign) newly diagnosed breast tumors were evaluated. The patients underwent 3.0 T MR examinations including diffusion-weighted imaging and synthetic MR. Two radiologists independently measured ADCs, T1 relaxation time (T1), T2 relaxation time (T2), and proton density (PD) using four ROI methods: round, square, freehand, and whole-tumor volume (WTV). The interclass correlation coefficient (ICC) was used to assess their measurement reliability. Diagnostic performance was evaluated using multivariate logistic regression analysis and the receiver operating characteristic (ROC) curves. RESULTS: The mean values of all ROI methods showed good or excellent interobserver reproducibility (0.79-0.99) and showed the best diagnostic performance compared to the minimum and maximum values. The square ROI exhibited superior performance in differentiating between benign from malignant breast lesions, followed by the freehand ROI. T2, PD, and ADC values were significantly lower in malignant breast lesions compared to benign ones for all ROI methods (p < 0.05). Multiparameters of T2 + ADC demonstrated the highest AUC values (0.82-0.95), surpassing the diagnostic efficacy of ADC or T2 alone (p < 0.05). CONCLUSION: ROI placement significantly influences ADC and synthetic MR values measured in breast tumors. Square ROI and mean values showed superior performance in differentiating benign and malignant breast lesions. The multiparameters of T2 + ADC surpassed the diagnostic efficacy of a single parameter.
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High quantum efficiency and wide-band detection capability are the major thrusts of infrared sensing technology. However, bulk materials with high efficiency have consistently encountered challenges in integration and operational complexity. Meanwhile, two-dimensional (2D) semimetal materials with unique zero-bandgap structures are constrained by the bottleneck of intrinsic quantum efficiency. Here, we report a near-mid infrared ultra-miniaturized graphene photodetector with configurable 2D potential well. The 2D potential well constructed by dielectric structures can spatially (laterally and vertically) produce a strong trapping force on the photogenerated carriers in graphene and inhibit their recombination, thereby improving the external quantum efficiency (EQE) and photogain of the device with wavelength-immunity, which enable a high responsivity of 0.2 A/W-38 A/W across a broad infrared detection band from 1.55 to 11 µm. Thereafter, a room-temperature detectivity approaching 1 × 109 cm Hz1/2 W-1 is obtained under blackbody radiation. Furthermore, a synergistic effect of electric and light field in the 2D potential well enables high-efficiency polarization-sensitive detection at tunable wavelengths. Our strategy opens up alternative possibilities for easy fabrication, high-performance and multifunctional infrared photodetectors.
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Materials showing second-order nonlinear transport under time reversal symmetry can be used for Radio Frequency (RF) rectification, but practical application demands room temperature operation and sensitivity to microwatts level RF signals in the ambient. In this study, we demonstrate that BiTeBr exhibits a giant nonlinear response which persists up to 350 K. Through scaling and symmetry analysis, we show that skew scattering is the dominant mechanism. Additionally, the sign of the nonlinear response can be electrically switched by tuning the Fermi energy. Theoretical analysis suggests that the large Rashba spin-orbit interactions (SOI), which gives rise to the chirality of the Bloch electrons, provide the microscopic origin of the observed nonlinear response. Our BiTeBr rectifier is capable of rectifying radiation within the frequency range of 0.2 to 6 gigahertz at room temperature, even at extremely low power levels of -15 dBm, and without the need for external biasing. Our work highlights that materials exhibiting large Rashba SOI have the potential to exhibit nonlinear responses at room temperature, making them promising candidates for harvesting high-frequency and low-power ambient electromagnetic energy.
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PURPOSE: This study investigates how access to assistive technologies affects employment and earnings among people with disabilities. METHODS: We first document employment and earnings gaps associated with specific impairments and activity limitations using 2017-2021 American Community Survey and 2014 Survey of Income and Program Participation data. We then use accommodations data from the 2012, 2019, and 2021 Current Population Survey (CPS) Disability Supplements to examine employment and earnings growth for people with disabilities related both to any, and to technology-based, accommodations. We also provide short descriptions of three developing assistive technologies that assist people with upper body impairments, visual impairments, and anxiety conditions. RESULTS: Almost all impairments and activity limitations are linked to lower employment and earnings, with especially low employment among people with mobility impairments and particularly low earnings among those with cognitive impairments. About one-tenth of workers with disabilities received any accommodations, and 3-4% received equipment-based accommodations in the 2012-2021 period; these figures increased slightly over the period. The occupations with the highest disability accommodations rates had greater disability employment growth from 2012 to 2021, but disability pay gaps did not decrease more in these occupations. The three developing assistive technologies we describe illustrate the potential to reduce the estimated employment and earnings deficits. CONCLUSION: Assistive technology accommodations have potential for improving employment outcomes for people with disabilities.