Abstract Despite the swift development in perovskite solar cells (PSCs), great concerns regarding environmental vulnerability propose a big challenge for their long‐term operational stability. ...Herein, a novel functionalized ultraviolet (UV) conversion small molecule, Coumarin 153 (C153), is judiciously introduced into perovskite precursor to effectively enhance device efficiency and operational stability against UV radiation. It is found that the uncoordinated Pb 2+ and A‐site vacancies of perovskite can be successfully fixed through Lewis acid–base coordination and hydrogen bonding upon C153 treatment, resulting in a stabilized structure with remarkably reduced intrinsic defects. Concurrently, the incremental visible light absorption derived from the down‐conversion effect of C153 molecules together with the optimized energy level arrangement contribute to the substantially enhanced photocurrent of the device. As a result, the resultant device delivers a champion efficiency of 24.73%, accompanied by greatly improved operational stability against environments, with retaining over 90% of initial PCE for ≈380, ≈1400, and 1710 h aging under continuous UV radiation, heating stress, and illumination, respectively. This work provides an effective and feasible strategy toward high‐efficiency and environment‐stable PSCs.
It was essential to identify individuals at high risk of fragility fracture and prevented them due to the significant morbidity, mortality, and economic burden associated with fragility fracture. The ...quantitative ultrasound (QUS) showed promise in assessing bone structure characteristics and determining the risk of fragility fracture.BACKGROUNDIt was essential to identify individuals at high risk of fragility fracture and prevented them due to the significant morbidity, mortality, and economic burden associated with fragility fracture. The quantitative ultrasound (QUS) showed promise in assessing bone structure characteristics and determining the risk of fragility fracture.To evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragility fractures retrospectively in postmenopausal women, and compared it with the traditional parameter of QUS, speed of sound (SOS), and bone mineral density (BMD) acquired with dual X-ray absorptiometry (DXA).AIMSTo evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragility fractures retrospectively in postmenopausal women, and compared it with the traditional parameter of QUS, speed of sound (SOS), and bone mineral density (BMD) acquired with dual X-ray absorptiometry (DXA).Using QUS, RF signal and SOS were acquired for 246 postmenopausal women. An MResNet was utilized, based on the RF signal, to categorize individuals with an elevated risk of fragility fracture. DXA was employed to obtain BMD at the lumbar, hip, and femoral neck. The fracture history of all adult subjects was gathered. Analyzing the odds ratios (OR) and the area under the receiver operator characteristic curves (AUC) was done to evaluate the effectiveness of various methods in discriminating fragility fracture.METHODSUsing QUS, RF signal and SOS were acquired for 246 postmenopausal women. An MResNet was utilized, based on the RF signal, to categorize individuals with an elevated risk of fragility fracture. DXA was employed to obtain BMD at the lumbar, hip, and femoral neck. The fracture history of all adult subjects was gathered. Analyzing the odds ratios (OR) and the area under the receiver operator characteristic curves (AUC) was done to evaluate the effectiveness of various methods in discriminating fragility fracture.Among the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was competent to discriminate any fragility fracture (OR = 2.64; AUC = 0.74), Vertebral fracture (OR = 3.02; AUC = 0.77), and non-vertebral fracture (OR = 2.01; AUC = 0.69). After being modified by clinical covariates, the efficiency of MResNet was further improved to OR = 3.31-4.08, AUC = 0.81-0.83 among all fracture groups, which significantly surpassed QUS-SOS (OR = 1.32-1.36; AUC = 0.60) and DXA-BMD (OR = 1.23-2.94; AUC = 0.63-0.76).RESULTSAmong the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was competent to discriminate any fragility fracture (OR = 2.64; AUC = 0.74), Vertebral fracture (OR = 3.02; AUC = 0.77), and non-vertebral fracture (OR = 2.01; AUC = 0.69). After being modified by clinical covariates, the efficiency of MResNet was further improved to OR = 3.31-4.08, AUC = 0.81-0.83 among all fracture groups, which significantly surpassed QUS-SOS (OR = 1.32-1.36; AUC = 0.60) and DXA-BMD (OR = 1.23-2.94; AUC = 0.63-0.76).This pilot cross-sectional study demonstrates that the MResNet model based on the ultrasonic RF signal shows promising performance in discriminating fragility fractures in postmenopausal women. When incorporating clinical covariates, the efficiency of the modified MResNet is further enhanced, surpassing the performance of QUS-SOS and DXA-BMD in terms of OR and AUC. These findings highlight the potential of the MResNet as a promising approach for fracture risk assessment. Future research should focus on larger and more diverse populations to validate these results and explore its clinical applications.CONCLUSIONSThis pilot cross-sectional study demonstrates that the MResNet model based on the ultrasonic RF signal shows promising performance in discriminating fragility fractures in postmenopausal women. When incorporating clinical covariates, the efficiency of the modified MResNet is further enhanced, surpassing the performance of QUS-SOS and DXA-BMD in terms of OR and AUC. These findings highlight the potential of the MResNet as a promising approach for fracture risk assessment. Future research should focus on larger and more diverse populations to validate these results and explore its clinical applications.
Our previous studies have shown that the Adipose‐derived mesenchymal stem cells (ADSCs) can regulate metastasis and development of ovarian cancer. However, its specific mechanism has yet to be fully ...revealed. In this study, an RNA‐seq approach was adopted to compare the differences in mRNA levels in ovarian cancer cells being given or not given ADSCs. The mRNA level of paired box 8 (PAX8) changed significantly and was confirmed as an important factor in tumour‐inducing effect of ADSCs. In comparison with the ovarian cancer cells cultured in the common growth medium, those cultured in the medium supplemented with ADSCs showed a significant increase of the PAX8 level. Moreover, the cancer cell growth could be restricted, even in the ADSC‐treated group (P < .05), by inhibiting PAX8. In addition, an overexpression of PAX8 could elevate the proliferation of ovarian cancer cells. Moreover, Co‐IP assays in ovarian cancer cells revealed that an interaction existed between endogenous PAX8 and TAZ. And the PAX8 levels regulated the degradation of TAZ. The bioluminescence images captured in vivo manifested that the proliferation and the PAX8 expression level in ovarian cancers increased in the ADMSC‐treated group, and the effect of ADSCs in promoting tumours was weakened through inhibiting PAX8. Our findings indicate that the PAX8 expression increment could contribute a role in promoting the ADSC‐induced ovarian cancer cell proliferation through TAZ stability regulation.
Federated learning (FL) is an emerging machine learning setting designed to preserve privacy. However, constantly updating model parameters on uplink channels results in huge communication overload, ...which is a major challenge for FL. In this paper, we consider an adaptive gradient quantization approach based on rate-distortion optimization in FL, which consists of a non-stationary random walk model on the true global optimal model parameters. Unlike traditional quantization methods, our goal is to minimize the total communication costs when the global server reconstructs model parameters under distortion constraints. Furthermore, when considering the iterative process, we utilize the Kalman filter to reduce computational complexity. And in each iteration, a generalized water-filling algorithm is used to calculate the optimal quantization levels for each local client. Numerical results show that the proposed method outperforms conventional quantization methods in terms of reducing communication costs.
In this paper, a selective nickel ions chelating adsorbents (Ni-CMCS) were prepared based on carboxymethyl chitosan by ion imprinting technique. Scanning electron microscope (SEM), Fourier transform ...infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) were used to investigate their physicochemical properties. Brunauer-Emmett-Teller (BET) analysis showed that the BET surface area of Ni-CMCS had a significant increase after ion imprinting process. The effects of pH value, contact time and initial concentration of Ni(II) were studied. The adsorption kinetics were investigated, which indicated that Ni-CMCS was better fitted with pseudo-second-order kinetic model (R
2
= 0.9991) with film diffusion process as rate controlling step. The adsorption isotherms study indicated that Langmuir model matched better with the experimental data for Ni-CMCS (R
2
= 0.9617). Besides, the maximum adsorption capacity calculated from the Langmuir equation was 82.78 mg g
−1
. Moreover, the selectivity experiment suggested that Ni-CMCS had good selectivity in the presence of Co(II), Mn(II), or Cd(II). After used four cycles, Ni-CMCS kept great adsorption capacity.
Federated Learning (FL) is an emerging machine learning framework designed to preserve privacy. However, the continuous updating of model parameters over uplink channels with limited throughput leads ...to a huge communication overload, which is a major challenge for FL. To address this issue, we propose an adaptive gradient quantization approach that enhances communication efficiency. Aiming to minimize the total communication costs, we consider both the correlation of gradients between local clients and the correlation of gradients between communication rounds, namely, in the time and space dimensions. The compression strategy is based on rate distortion theory, which allows us to find an optimal quantization strategy for the gradients. To further reduce the computational complexity, we introduce the Kalman filter into the proposed approach. Finally, numerical results demonstrate the effectiveness and robustness of the proposed rate-distortion optimization adaptive gradient quantization approach in significantly reducing the communication costs when compared to other quantization methods.
A microsphere biosorbent with uniform size (CV = 1.52%), controllable morphology and component, and high mechanical strength was synthesized from chitosan by microfluidic technology combining with ...chemical crosslinking and solvent extraction. This chitosan microsphere (CS-MS) was prepared with a two-step solidification process, which was acquired by drying for the enhancement of mechanical property in final. The adsorption behavior of CS-MS towards copper (II) and main influencing factors on adsorption performance were investigated by batch experiments. Kinetic data hig-hlighted dominant chemical bonding along with electrons transferring in adsorption process. Isothermal analysis indicated that adsorption capacity was relevant to the number of active site. All these explorations provided a new direction for preparing highly comprehensive performance sorbent used in heavy metal treatment via microfluidic technology.
A one-pot three component 1,3-dipolar cycloaddition reaction of an aldehyde, α-aminomalonate, and nitroalkene has been developed through binaphthol derived chiral phosphoric acids. This reaction ...represents one of the most enantioselective catalytic approaches to access structurally diverse pyrrolidine derivatives.
Perovskite solar cells (PSCs) have recently attracted rapid interest for harvesting solar energy. However, the defects in perovskite absorber and vulnerability of charge‐transporting layer lead to ...unsatisfying stability, which limits their practical applications. Herein, we demonstrate that the addition of a piperidyl ionic liquid, that is, 1‐butyl‐1‐methylpiperidinium bis(trifluoromethyl sulfonyl)imide (BMP+TFSI−), can serve as a dual functional additive for passivating the intrinsic defects in perovskite and simultaneously improving the hydrophobicity of hole transport layer. Consequently, the power conversion efficiency for the optimal planar PSCs significantly increases from 21.07% to 23.34%. Impressively, the unencapsulated champion cells display promising stability with a reservation over 80% of the initial efficiency after exposure to moisture air (65% ± 5% relative humidity) for 1600 h. This work provides a facile strategy toward enhancing the efficiency and stability of PSCs.
A dual‐functional piperidyl ionic liquid for enhancing the performance of perovskite solar cells is demonstrated by passivating intrinsic defects in the perovskite absorber and simultaneously doping the hole transport layer with improved hydrophobicity. The optimal device produces a champion efficiency of 23.34% with a significantly increased stability in moisture air.
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