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Despite the success of deep learning methods in multi-modality segmentation tasks, they typically produce a deterministic output, neglecting the underlying uncertainty. The absence of uncertainty could lead to over-confident predictions with catastrophic consequences, particularly in safety-critical clinical applications. Recently, uncertainty estimation has attracted increasing attention, offering a measure of confidence associated with machine decisions. Nonetheless, existing uncertainty estimation approaches primarily focus on single-modality networks, leaving the uncertainty of multi-modality networks a largely under-explored domain. In this study, we present the first exploration of multi-modality uncertainties in the context of tumor segmentation on PET/CT. Concretely, we assessed four well-established uncertainty estimation approaches across various dimensions, including segmentation performance, uncertainty quality, comparison to single-modality uncertainties, and correlation to the contradictory information between modalities. Through qualitative and quantitative analyses, we gained valuable insights into what benefits multi-modality uncertainties derive, what information multi-modality uncertainties capture, and how multi-modality uncertainties correlate to information from single modalities. Drawing from these insights, we introduced a novel uncertainty-driven loss, which incentivized the network to effectively utilize the complementary information between modalities. The proposed approach outperformed the backbone network by 4.53 and 2.92 Dices in percentages on two PET/CT datasets while achieving lower uncertainties. This study not only advanced the comprehension of multi-modality uncertainties but also revealed the potential benefit of incorporating them into the segmentation network.

Large pinhole-free, high-crystal-quality perovskite films are the key to realizing efficient, stable CsPbI3perovskite modules. In this work, we use the crystal growth modulation strategy to prepare high-quality CsPbI3films from small to large sizes using a new precursor solution with CsI/DMAPbI3/PbI2in a DMAAc/DMF mixed solvent (DMAAc: dimethylamine acetate). The champion small-size CsPbI3device presents a photoelectric conversion efficiency (PCE) above 21% and a certified PCEof 20.05%, and the best blade-coated CsPbI3minimodule exhibits a PCEof 18.3% for an aperture area of 12.39 cm2and a PCEof 19.9% for an active area of 11.40 cm2. In addition, the composition engineering of the precursor solution toward CsPbI3crystallization is explored: the DMAAc/DMF mixed solvent can facilitate phase transformation and reduce the nucleation rate, and the mixture of PbI2and DMAPbI3will further improve the film microstructure and uniformity. Consequently, the anti-humidity stability and phase stability of the CsPbI3films are greatly improved, and the corresponding devices exhibit good operational stability. CsPbI3modules with simple encapsulation also present excellent long-term storage stability over 150 days. This crystal growth regulation strategy provides a new method to produce large-scale CsPbI3and even hybrid perovskite solar cells for future commercialization.

Structured illumination microscopy (SIM) provides an enhanced resolving power surpassing the optical diffraction limit by optical modulation of patterned illuminations. Although end-to-end deep learning techniques have recently advanced the reconstruction of SIM images, the reconstruction fidelity of existing networks is still moderate. We experimentally point out the crux lies in the inability of these models for faithful frequency learning. As a remedy, we propose a dual-domain learning strategy for SIM reconstruction, namely DDL-SIM, which learns to reconstruct SIM images from raw images in the spatial domain and raw image spectra in the frequency domain simultaneously, with the goal of narrowing the reconstruction gaps in both domains, thereby better recovering modulated frequencies and resolving more fine structures. Reconstruction experiments across various biological structures demonstrate the proposed DDL-SIM significantly improves the reconstruction fidelity of SIM images and shows great robustness against reconstruction artifacts.

The melon fly, Zeugodacus cucurbitae Coquillett (Diptera: Tephritidae), is an important quarantine pest prevalent worldwide. Heat shock protein 70s (Hsp70s) are crucial proteins involved in thermal stress tolerance. In the current study, we identified and cloned four Hsp70 genes from melon fly, namely ZcHsp70-1, ZcHsp70-2, ZcHsp70-3 and ZcHsp70-4. Phylogenetic analysis showed that they had a close genetic relationship with Hsp70s from Diptera insects. Their spatio-temporal expression showed that they were highly expressed in the midgut of 5-d-old adults. After a moderate high-temperature (38°C) induction, only ZcHsp70-1 and ZcHsp70-2 were found to be up-regulated by 6.10-fold and 7.76-fold, respectively. After extreme high-temperature (42°C) induction, only ZcHsp70-1 was found to be up-regulated to a very high level by 117.87-fold. ZcHsp70-1 and ZcHsp70-2 were heterologously expressed in Escherichia coli, and the ATPase activity of the purified recombinant proteins was significantly increased upon 38°C and 42°C treatment. These recombinant proteins also effectively improved the tolerance of E. coli in response to high-temperature stress. In vivo, separate suppression of ZcHsp70-1 or ZcHsp70-2 expression did not affect the mortality of melon fly to high-temperature stress of 38°C, whereas suppression of both genes increased the mortality. In addition, only suppression of ZcHsp70-1 expression increased the mortality to extremely high-temperature stress of 42°C. Our data show that ZcHsp70-1 and ZcHsp70-2 play essential roles in high-temperature tolerance but differ in their relationship to the extreme high-temperature tolerance of the melon fly.

Accurate segmentation of abdominal organs on MRI is crucial for computer-aided surgery and computer-aided diagnosis. Most state-of-the-art methods for MRI segmentation employ an encoder-decoder structure, with skip connections concatenating shallow features from the encoder and deep features from the decoder. In this work, we noticed that simply concatenating shallow and deep features was insufficient for segmentation due to the feature gap between shallow features and deep features. To mitigate this problem, we quantified the feature gap from spatial and semantic aspects and proposed a spatial loss and a semantic loss to bridge the feature gap. The spatial loss enhanced spatial details in deep features, and the semantic loss introduced semantic information into shallow features. The proposed method successfully aggregated the complementary information between shallow and deep features by formulating and bridging the feature gap. Experiments on two abdominal MRI datasets demonstrated the effectiveness of the proposed method, which improved the segmentation performance over a baseline with nearly zero additional parameters. Particularly, the proposed method has advantages for segmenting organs with blurred boundaries or in a small scale, achieving superior performance than state-of-the-art methods.

ABSTRACTThe germination of carrot seeds is a complex regulatory process and the relationship between phytohormone and carrot seed germination is unclear. We performed morphological observation, transcriptome sequencing, phytohormone content determination, and gene expression profiles analysis. The results showed that the white hypocotyls of carrot seeds grew rapidly on the 3 d, and cotyledons unfold on the 8 d. A total of 745 differentially expressed genes (DEGs) related to plant hormone signal transduction were identified at different germination stages (3, 5, 8 d), and most of the genes were up-regulated obviously in the later stage. The content of GA3 reached its peak on the first day of germination, with a content of 7.12 ng/g FW, and showed a trend of first decreasing, then increasing and decreasing. And the trend of GA4 content change was similar to GA3 content from 2 d to 8 d. The contents of indole-3-acetic acid (IAA) and methyl jasmonate (MeJA) showed a gradual increasing trend, while the content of abscisic acid (ABA) gradually decreased. The results of RT-qPCR showed that DcGA3ox1 and DcAOC expressed decreased, while DcGA20ox2 and DcYUCCA increased in the whole process. These results provide potential new insights for the efficient production of carrots..

Defect states in perovskite films restrict the interfacial stability and open-circuit voltage of perovskite solar cells. Here, aiming at superior interfacial passivation, we investigate the reconfiguration of perovskite interface by the interaction between a series of quaternary ammonium bromides (QAB) and lead—halide (Pb—X) octahedrons. Bromide—iodide substitution reaction or R4NBr addition reaction may occur on the perovskite surface, which is related to the steric hindrance of quaternary ammonium cations. On this basis, the perovskite surface morphology, band structure, growth orientation and defect states are reconstructed viathe R4NBr addition reaction. This ordered lead—halide adduct could effectively repair the imperfect perovskite/hole transportation layer interface to suppress non-radiative recombination and ion migration toward ultralong carrier lifetime surpassing 10 µs. The resulting perovskite solar cells yield the efficiency of 23.89% with steady-state efficiency of 23.70%. The passivated cells can sustain 86% of initial efficiency after 200-h operation, which is attributed to the passivation effect and hydrophobic characteristics. This work provides an avenue for reconfiguring perovskite surface by QABs.

Formamidinium-cesium (FA-Cs) lead halide has attracted wide interest for enhancing the stability of perovskite solar cells; however, the crystallization of FA-Cs perovskite usually suffers from more complicated intermediate phase transition processes. Herein, we have developed a dual-functional additive consisting of organic ammonium cation and dithiocarbamate anion to regulate the crystallization and defects of the FA-Cs perovskite film. With a synergistic contribution of the cationic and anionic groups, 24.25% efficiency has been achieved in a single cell with excellent operational stability. Under steady-state light illumination and bias voltage, 90% power output of its initial state can still be obtained after 500 h of continuous operation. After enlarging the device from single cell to module, >20.5% efficiency has been realized from a 10.4 cm2minimodule by using only an ultralow-cost laser scribing technology. Briefly, this exploitation of cation-anion synergistic effect from dual-functional additives provides more opportunities for promoting the development of perovskite solar cells.

A sensitive and effective method was developed for the simultaneous determination of 14 odorous compounds in drinking water using gas chromatography-mass spectrometry (GC-MS) coupled with headspace solid phase microextraction (HS-SPME) pretreatment. The influencing factors including SPME fiber, ionic strength, temperature and time on the pretreatment procedure were evaluated systematically. Under the optimized conditions, 10 mL of the samples added with 1.0 g sodium chloride was extracted by CAR/PDMS fiber at 60 °C for 30 min and then desorbed at 280 °C for 3 min. The analytes achieved good linearity as the mass concentrations were in the range of 0.0020–10.0 μg L−1with correlation coefficients higher than 0.9990. The limits of detection (LODs) ranging between 0.2 and 50 ng L−1were lower than the olfactory threshold of these studied compounds. Satisfactory recoveries were obtained ranging from 84.8% to 110.6%, and good reproducibility indicated by relative standard deviation (RSD) in the range of 0.50–9.5% was obtained as well. The proposed method was convenient, sensitive and accurate, which was suitable for the routine monitoring 14 odorous compounds in water.

The stability issue hinders the commercialization of the perovskite solar cells (PSCs), which is widely recognized. The efficiency generally decreases over time during the working condition. Here, we report an efficiency enhancement phenomenon of PSCs in the stability test at the maximum power point, which is speculated to be related to the electric-field-induced ion migration. The defect density and efficiency-related parameters were traced in situ by admittance spectroscopy and transient photovoltage when the cell works under bias voltage. The performance enhancement was revealed to be attributed to the reduction of the cell defects owing to ion migration. An efficiency of 22.3% can be achieved after the bias voltage was kept for 8 h. These findings suggest that ion migration is a double-edged sword that affects the electrical stability of PSCs, which presents a potential approach to improve the device’s stability by appropriately controlling the defect states.

Positron emission tomography (PET) and computed tomography (CT) are widely used imaging modalities in radiation oncology. PET imaging has a high contrast but often leads to blurry tumor edges due to its limited spatial resolution, while CT imaging has a high resolution but a low contrast between a tumor and its surrounding normal soft tissues. Tumor segmentation from either a single PET or CT image is difficult. It is known that co-segmentation methods utilizing the complementary information between PET and CT can improve the segmentation accuracy. This complementary information can be either consistent or inconsistent in the image level. How to correctly localize tumor edges with the inconsistent information is one major challenge for co-segmentation. This paper proposes a novel variational method for tumor co-segmentation in PET/CT, with a fusion strategy specifically designed to handle the information inconsistency between PET and CT in an adaptive way-the method can automatically decide which modality should be more trustful when PET and CT disagree to each other for localizing the tumor boundary. A PET restoration process is further integrated into the co-segmentation process, which further eliminates the uncertainty for tumor segmentation introduced by tumor edge blur in PET. The performance of the proposed method is validated on 50 nonsmall cell lung cancer patients. It achieves an average dice similarity indexes (DSIs) of 0.85 ± 0.06, volume error (VE) of 0.09 ± 0.08, and classification error (CE) of 0.31 ± 0.13. The proposed method has a high accuracy for PET/CT tumor co-segmentation and PET restoration.

The imaging rate of structured illumination microscopy (SIM) reached 188 Hz recently. As the exposure time decreases, the camera detects fewer virtual photons, while the noise level remains the same. As a result, the signal-to-noise ratio (SNR) decreases sharply. Furthermore, the SNR decreases further because of photobleaching and phototoxicity. This decreased quality of SIM raw data may lead to surprising artifacts with various causes, which may confuse a new user of SIM microscopy. We summarize three significant possible sources of severe artifacts in reconstructed super-resolution (SR) images. Ultrafast motion of a biological sample or an uneven illumination pattern is the most difficult to be identified. The estimated parameter could also be incorrect, leading to artifact of regular patterns. Furthermore, reconstruction with the Wiener method generates stochastic artifacts due to the amplification of noise during the deconvolution process. To deal with these problems, we have established a protocol to reconstruct ultrafast SIM raw data obtained in low SNR conditions. First, we checked the quality of the raw data with the ImageJ plugin SIMcheck before reconstruction. Then, a modified parameter estimation method was used to improve the precision of the parameters. Finally, an iterative algorithm was used for SIM reconstruction under low signal-to-noise ratio conditions. This procedure effectively suppressed the artifacts in the super-resolution images reconstructed from raw data of low signal-to-noise ratio.

Total internal reflection fluorescence microscopy (TIRF microscopy) uses a rapid decay of evanescent waves to excite fluorophores within several hundred nanometers (nm) beneath the plasma membrane, which can effectively suppress excitation of fluorescence signals in the deep layers. From image stacks obtained with a plurality of different incident angles, a three-dimensional spatial structure of the observed sample can be reconstructed by a Multi-Angle-TIRF (MA-TIRF) algorithm that provides an axial resolution of ~50 nm. Taking into account the point spread function (PSF) of the TIRF microscopes, we further increase its lateral resolution by introducing a fast deconvolution algorithm into the reconstruction of MA-TIRF data (DMA-TIRF), which is approached in just one step of minimizing the reconstruction function. We also introduce a TV regularization term in the deconvolution algorithm to suppress artifacts induced by the excessive noise. Therefore, based on the hardware of existing MA-TIRF microscopes, the proposed DMA-TIRF algorithm has achieved lateral and axial resolutions of ~200 and ~50 nm, respectively.

ABSTRACTDynorphins act as endogenous anticonvulsants via activation of kappa opioid receptor (KOR). However, the mechanism underlying the anticonvulsant role remains elusive. This study aims to investigate whether the potential protection of KOR activation by dynorphin against epilepsy was associated with the regulation of PI3K/Akt/Nrf2/HO-1 pathway. Here, a pilocarpine-induced rat model of epilepsy and Mg2+-free-induced epileptiform hippocampal neurons were established. Decreased prodynorphin (PDYN) expression, suppressed PI3K/Akt pathway, and activated Nrf2/HO-1 pathway were observed in rat epileptiform hippocampal tissues and in vitroneurons. Furthermore, dynorphin activation of KOR alleviated in vitroseizure-like neuron injury via activation of PI3K/Akt/Nrf2/HO-1 pathway. Further in vivoinvestigation revealed that PDYN overexpression by intra-hippocampus injection of PDYN-overexpressing lentiviruses decreased hippocampal neuronal apoptosis and serum levels of inflammatory cytokines and malondialdehyde (MDA) content, and increased serum superoxide dismutase (SOD) level, in pilocarpine-induced epileptic rats. The protection of PDYN in vivowas associated with the activation of PI3K/Akt/Nrf2/HO-1 pathway. In conclusion, dynorphin activation of KOR protects against epilepsy and seizure-induced brain injury, which is associated with activation of the PI3K/Akt/Nrf2/HO-1 pathway.

The exposure of normal tissues to high radiation during cone-beam CT (CBCT) imaging increases the risk of cancer and genetic defects. Statistical iterative algorithms with the total variation (TV) penalty have been widely used for low dose CBCT reconstruction, with state-of-the-art performance in suppressing noise and preserving edges. However, TV is a first-order penalty and sometimes leads to the so-called staircase effect, particularly over regions with smooth intensity transition in the reconstruction images. A second-order penalty known as the Hessian penalty was recently used to replace TV to suppress the staircase effect in CBCT reconstruction at the cost of slightly blurring object edges. In this study, we proposed a new penalty, the TV-H, which combines TV and Hessian penalties for CBCT reconstruction in a structure-adaptive way. The TV-H penalty automatically differentiates the edges, gradual transition and uniform local regions within an image using the voxel gradient, and adaptively weights TV and Hessian according to the local image structures in the reconstruction process. Our proposed penalty retains the benefits of TV, including noise suppression and edge preservation. It also maintains the structures in regions with gradual intensity transition more successfully. A majorization-minimization (MM) approach was designed to optimize the objective energy function constructed with the TV-H penalty. The MM approach employed a quadratic upper bound of the original objective function, and the original optimization problem was changed to a series of quadratic optimization problems, which could be efficiently solved using the Gauss-Seidel update strategy. We tested the reconstruction algorithm on two simulated digital phantoms and two physical phantoms. Our experiments indicated that the TV-H penalty visually and quantitatively outperformed both TV and Hessian penalties.

The free oscillation of liquid droplet is one of the classical questions in science research, liquid drops play important role in a lot of engineering applications. Theory study of droplet oscillation mainly based on the linear method, this method is only adapted to the small-amplitude oscillatory motion of drops. Except the linear method used in this study, numerical method have been successfully applied in simulation of the free oscillation of liquid droplet. In this paper, the finite element method is used to investigate numerically the influence of viscoelasticity on the small-amplitude oscillation of drop of polymer solutions. A spatial discretization is accomplished by the finite element method, the time descretization is carried by the Crank-Nicolson method, and the arbitrary Lagangian-Eulerian (ALE) method is used to track the change of the interface. Numerical results are compared with the ones of linear theory. The behaviors of oscillation are found to depend on the viscosity and the stress relaxation time of viscoelastic fluid, the results of numerical simulation and linear theory are identical.

Acute traumatic coagulopathy (ATC) may trigger sympathoadrenal activation associated with endothelial damage and coagulation disturbances. Overexcitation of sympathetic nerve in this state would disrupt sympathetic–vagal balance, leading to autonomic nervous system dysfunction. The aim of this study was to evaluate the autonomic function in ATC and its influence on inflammation, endothelial and coagulation activation. Male Sprague–Dawley rats were randomly assigned to sham, ATC control (ATCC) and ATC with sympathectomy by 6-hydroxydopamine (ATCS) group. Sham animals underwent the same procedure without trauma and bleeding. Following trauma and hemorrhage, rats underwent heart rate variability (HRV) test, which predicts autonomic dysfunction through the analysis of variation in individual R-R intervals. Then, rats were euthanized at baseline, and at 0, 1 and 2 h after shock and blood gas, conventional coagulation test and markers of inflammation, coagulation, fibrinolysis, endothelial damage and catecholamine were measured. HRV showed an attenuation of total power and high frequency, along with a rise of low frequency and low frequency : high frequency ratio in the ATC rats, which both were reversed by sympathectomy in the ATCS group. Additionally, sympathetic denervation significantly suppressed the increase of proinflammatory cytokines, tumor necrosis factor-α and the fibrinolysis markers including tissue-type plasminogen activator and plasmin–antiplasmin complex. Serum catecholamine, soluble thrombomodulin and syndecan-1 were also effectively inhibited by sympathectomy. These data indicated that autonomic dysfunction in ATC involves both sympathetic activation and parasympathetic inhibition. Moreover, sympathectomy yielded anti-inflammatory, antifibrinolysis and endothelial protective effects in rats with ATC. The role of autonomic neuropathy in ATC should be explored further.

Olivine catalysts prepared by calcination achieved high N2selectivity and good NH3-SCR activity at 150–450 °C. The existence of SO2significantly inhibited the formation of NO and N2O in the NH3-SCR reaction at the temperature range of 325–450 °C. This is mainly because of the reductive properties of SO2that could restrain the over-oxidization of NH3. Therefore, both the NOxconversion and N2selectivity were improved at high temperatures. Accordingly, the presence of SO2shifted the optimal temperature window of the olivine catalyst by about 75 °C towards high temperature. Both the Langmuir–Hinshelwood mechanism and the Eley–Rideal mechanism contributed to the SCR reaction over the olivine catalyst. Temperature-programmed desorption experiments show that excess ammonium sulfate formed in the presence of SO2suppressed the reaction of adsorbed NOxspecies with adsorbed NH3species at low temperatures. Lots of activated NH3species (−NH2) were formed by the decomposition of ammonium sulfate at high temperatures, promoting the reaction of adsorbed NH3species (−NH2) with both adsorbed NOxand gaseous NOx. Preliminary results suggest that olivine is a potential catalyst for treating sulfur-containing exhausts.

After analysising the principle of nonsubsampled contourlet transform, the image fusion model based on HIS transform and nonsubsampled contourlet transform is proposed. By taking of ALOS image as an example, the image fusion of multi-spectral band and panchromatic band at the same time is carried out by different fusion methods such as the method combining HIS transform and nonsubsampled contourlet transform (NSCT), HIS transform fusion method, principal component analysis (PCA), Brovey and static wavelet transform (SWT). By calculating the quantitative evaluation indicators of the different fused image, it is conclued that the fusion effection of static wavelet transform fusion method and nonsubsampled contourlet transform fusion method is better than the common methods such as HIS transform, principal component analysis and Brovey. In particular, the image fusion effection of nonsubsampled contourlet transform method, which betterly maintains the image spectral information while improving image spatial resolution at the same time, is superior than the fusion evaluation of static wavelet transform fusion method.

Growth inhibition and apoptotic/necrotic phenotype was observed in nanogold particle (AuNP)-treated human chronic myelogenous leukemia cells. To elucidate the underlying cellular mechanisms, proteomic techniques including two-dimensional electrophoresis/mass spectrometry and protein microarrays were utilized to study the differentially expressed proteome and phosphoproteome, respectively. Systems biology analysis of the proteomic data revealed that unfolded protein-associated endoplasmic reticulum (ER) stress response was the predominant event. Concomitant with transcriptomic analysis using mRNA expression, microarrays show ER stress response in the AuNP-treated cells. The ER stress protein markers’ expression assay unveiled AuNPs as an efficient cellular ER stress elicitor. Upon ER stress, cellular responses, including reactive oxygen species increase, mitochondrial cytochrome crelease, and mitochondria damage, chronologically occurred in the AuNP-treated cells. Conclusively, this study demonstrates that AuNPs cause cell death through induction of unmanageable ER stress.

We are concerned with the performance evaluation of the ridgelet bi-frame for image denoising application. The ridgelet bi-frame is a new (as far as we know) bi-frame system that can efficiently deal with straight singularities in two dimensions. We show that, for images dominated by straight edges, the ridgelet bi-frame can obtain much better restoration results than wavelet systems. We also investigate the statistical properties of the ridgelet bi-frame coefficients of these images. Results indicate that the marginal distribution of ridgelet bi-frame coefficients has higher kurtosis than that of wavelet coefficients of the same images. We describe a simple method through which statistical denoising algorithms previously developed in the wavelet domain can be conveniently introduced into the ridgelet bi-frame domain. In addition, we use the ridgelet bi-frame to construct another new bi-frame system referred to as the curvelet bi-frame, which can be viewed as a generalized version of the curvelet. Experiment results show that the simple hard-threshold procedure in the curvelet bi-frame domain produces restoration results comparable with those due to the state-of-the-art denoising methods.

We develop a novel multivariate Bayesian wavelet estimator of a simple analytical form that is computationally effective for the image denoising problem. The estimator is derived from the multivariate Laplacian model by using the maximum a posteriori rule. We find the multivariate estimator produces restoration results of high quality, both visually and in terms of peak signal-to-noise ratio.

The hierarchically porous nitrogen-doped carbon (SHPNC) was fabricated by biorenewable carbon sources.The SHPNC electrode exhibited a high specific capacity, excellent cyclic stability, and superior rate capability.The asymmetric potassium-ion hybrid capacitors delivered a maximum energy density of 135 Wh kg-1, long lifespan with excellent capacity retention, and outstanding ultrafast charge/slow discharge performance.