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Capturing details of objects beyond the focal plane is challenging due to the limited depth-of-field (DoF) of optical systems. Here, we report a computational refocusing ghost Imaging (CRGI) method to extend the DoF of computational ghost imaging (CGI) systems. An ultra-fast and in situ point spread function (PSF) estimation method is put forward utilizing the optical characterization of the system and compressive sensing modulation. The PSF distribution is measured with in situ compressive sensing algorithm according to reciprocity property using the same CGI system. The convolution of PSFs of various depths with modulation patterns is reshaped into measurement matrices to computationally refocus objects at different depths. From one measurement, CRGI can rebuild distinct and well-focused images of multiple objects at different depths. According to experiments, CRGI can nearly quadruple the DoF of typical CGI methods. CRGI represents a significant advancement in CGI domain by computationally surpassing the optical DoF limitations. This discovery enables recording object features beyond the focus plane using extended depth-of-field. [ABSTRACT FROM AUTHOR]

Disclosed here is a palladium‐catalyzed direct [4+1] spiroannulation of ortho‐C−H bonds of naphthols with cyclic diaryliodonium salts to construct spirofluorenyl naphthalenones (SFNP) under mild reaction conditions. This spiroannulation directly transforms the hydroxy group into a carbonyl group, and also tolerates reactive functional groups such as the halo groups, which provide an opportunity to rapidly assemble structurally new thermally activated delayed fluorescent (TADF) materials that feature a carbonyl group with an adjacent spirofluorenyl unit as the acceptor. As an illustrated example, the OLED device utilizing the assembled DMAC‐SFNP as the host material exhibits a low turn‐on voltage of 2.5 V and an ultra‐high external quantum efficiency of 32.2 %. This work provides inspiration for structurally new TADF materials, and also displays the potential of C−H activation as a synthetic strategy for the innovation of optoelectronic materials. [ABSTRACT FROM AUTHOR]

Disclosed here is a palladium‐catalyzed direct [4+1] spiroannulation of ortho‐C−H bonds of naphthols with cyclic diaryliodonium salts to construct spirofluorenyl naphthalenones (SFNP) under mild reaction conditions. This spiroannulation directly transforms the hydroxy group into a carbonyl group, and also tolerates reactive functional groups such as the halo groups, which provide an opportunity to rapidly assemble structurally new thermally activated delayed fluorescent (TADF) materials that feature a carbonyl group with an adjacent spirofluorenyl unit as the acceptor. As an illustrated example, the OLED device utilizing the assembled DMAC‐SFNP as the host material exhibits a low turn‐on voltage of 2.5 V and an ultra‐high external quantum efficiency of 32.2 %. This work provides inspiration for structurally new TADF materials, and also displays the potential of C−H activation as a synthetic strategy for the innovation of optoelectronic materials. [ABSTRACT FROM AUTHOR]

In this work, we report novel Rh(iii)-catalyzed chemoselective functionalizations of tertiary aniline N-oxides with alkynes, including annulation via the sequential C(sp2)–H and C(sp3)–N activation for the formation of N-alkylindoles and an O-atom transfer (OAT) process for the synthesis of acetophenones. [ABSTRACT FROM AUTHOR]

The security of liveness detection in face recognition is a crucial issue, but many attacks can spoof current face feature techniques. To enhance the security of liveness detection, a method is proposed to extract human physiological components from the object and classify the properties. The proposed method, different from traditional camera-based methods that require specific movement of the human face, separates the heart rate (HR) components from the computational ghost imaging (CGI) signal and achieves liveness detection by capturing only one image rather than image sequences. The correct rate reaches 96.0% against picture attacks and mask attacks. The average error is only 3.57% compared to commercial contact HR measuring devices. Meanwhile, this method is found resolution-independent and can work in low-resolution conditions, which is experimentally verified at a resolution of 32 × 32 pixels. This method can enhance the security of liveness detection and provide a fresh framework for physiological measurements. [ABSTRACT FROM AUTHOR]

Abstract: Alloxan is a classical diabetogen which is used to achieve β-cell destruction and type 1 diabetes due to its selective cytotoxic effect on pancreatic β-cells. Although alloxan-induced diabetes is widely used in the laboratory to mimic diabetic pathology and for screening antidiabetic drugs, there has not been any comprehensive research in vivo on its diabetogenicity. In our study, alloxan-induced diabetic mice were generated by a single intravenous injection of alloxan (100mg/kg). Our data show that these mice possess hyperglycemia, hypoinsulinism and morphological characteristics of impaired pancreas that are consistent with the accepted diabetogenic effects of alloxan. Alloxan is believed to confer its diabetogenic effect by inhibiting pancreatic glucokinase activity, leading to pancreatic β-cell death. We examined the effects of alloxon on the other major site of glucokinase expression, the liver. Our results show that alloxan treatment led to an 81% reduction in glucokinase immunoreactivity and a greater than 90% reduction in glucokinase enzymatic activity in the liver, suggesting that alloxan''s toxicity is not specific to the pancreas. Given the important role of glucokinase as a glucose sensor, and our findings on the effects of alloxon on liver glucokinase activity we propose that the effects on the liver are the primary contributor to pathogenesis in alloxan-induced diabetes. Alloxan-induced diabetes is thus a multifactor-promoted diabetes model which still could be used to examine the antidiabetic effects of compounds prompting insulin secretion and increasing liver-specific glucokinase activity. Despite alloxan-induced diabetes being inconsistent with the natural pathogenesis of human diabetes, further research on the causes of decreased glucokinase activity will help us to unravel the pathogenesis of diabetes and its complications. [Copyright &y& Elsevier]

Objective: The primary objective was to construct a high-performing prognostic risk model to accurately forecast the prognosis of patients diagnosed with intrahepatic cholangiocarcinoma (iCCA). Methods: We retrospectively collected clinical data from the MSK database on 125 patients diagnosed with iCCA. Random sampling was utilized to divide patients into a training set and a validation set, maintaining a ratio of 7:3. Univariate and multivariate Cox proportional hazards regression models were utilized to identify independent prognostic factors influencing OS. Based on these independent factors, a model nomogram was established. The performance of the prognostic prediction models was assessed through calibration curves and C-index calculations. The Kaplan-Meier method was used to plot survival curves. Time-dependent ROC curve was used to evaluate the accuracy of the model. Results: A nomogram was developed, incorporating hepatitis C, CA19, tumor extent, tumor size, LVI, positive lymph nodes, and TMB as predictive factors. The C-index for the training set was.78 and the validation set was.68. Using the riskscore derived from the nomogram, patients were stratified into high- and low-risk groups. The high-risk group exhibited considerably lower OS and RFS compared to the low-risk group in the training set (P <.05). However, no significant difference was detected in RFS among different risk groups in the validation set (P >.05). The AUC for 1-year, 3-year, and 5-year survival was.89,.69, and.69, respectively. Conclusion: We successfully developed and validated a prognostic nomogram for iCCA, demonstrating its excellent accuracy in predicting patient outcomes and providing clinicians with a potential prognostic tool. [ABSTRACT FROM AUTHOR]

A computational ghost imaging encryption and watermarking method with a small key storage space is proposed. This method uses the Arnold transform to rearrange the measurement matrix in the computational ghost imaging (CGI), using the parameters in the transform as encryption/decryption keys. To reduce the risk of key leakage, the independent component analysis (ICA) method is introduced to analyze the CGI signals, making them statistically independent from each other and further increasing the difficulty of cracking. Two watermarking strategies are proposed that can identify illegal data tampering by verifying the integrity of the watermark. The feasibility of this method is verified by both numerical simulations and optical experiments. The research results represent an optical imaging encryption and watermarking technique with multi-images and multi-user characteristics. As its key storage requirements are small, it can be applied to confidential channels with low speeds, such as quantum cryptography. • The method has multi-image, multi-user encryption, and watermarking abilities. • The length of the key is small compared to existing methods. • Illegally tampered signal can be detected without damaging the original image. [ABSTRACT FROM AUTHOR]

In practical application environments, objects are rarely stationary, which makes it difficult to image dynamic objects with conventional single-pixel imaging (SI) techniques. In this paper, a rotationally synchronized single-pixel imaging (RS-SI) method is proposed to image a dynamic object in rotation. The modulation pattern rotates in sync with the rapidly rotating object, and the center of object rotation is ensured to be in line with the center of the illumination pattern. Then, RS-SI reconstruction algorithm is used to reconstruct the image of the rotating object by collecting the light reflected from the object's surface. This method does not require advanced knowledge of the object rotation speed to complete the imaging. Simulation and experimental results confirm that the RS-SI can reconstruct images of an object at rotational speeds up to 422.0 rpm and can also complete imaging of a variable-speed rotating object. Imaging results of 128 × 128 pixels at a sampling rate of 27.47% can be obtained with high fidelity. The proposed RS-SI is a method for imaging an object in rotation, providing insights for future applications of single-pixel imaging technology for defect detection in rotating parts. [ABSTRACT FROM AUTHOR]

In the case of aniline oxides (XI) with strong electron-withdrawing groups and cyclic aniline N-oxides (XIII) diphenylacetylene adds regioselectively in the ortho-position accompanied by an O-atom transfer. [ABSTRACT FROM AUTHOR]

Flotation is one of the most used methods to upgrade natural graphite resources. However, the efficiency is usually decreased due to the entrainment of undesirable fine gangue minerals. In this work, the impact of different factors such as particle size, pulp density, and flotation reagent on the entrainment of mica and quartz in a flake graphite flotation was studied. The single gangue mineral flotation results showed increased gangue entrainment when reducing the particle size of gangue minerals and increasing the pulp density. Moreover, the flotation of artificial mixtures indicated enhanced entrainment of mica and quartz in the presence of graphite particles. The collector and frother also strongly affect gangue entrainment by modifying the structure and stability of the froth. Kerosene, which has a prominent deforming feature, can reduce gangue entrainment more effectively than diesel. [ABSTRACT FROM AUTHOR]

Neurogenesis is the process by which neural stem cells (NSCs) proliferate and differentiate into neurons. This is diminished in several neurodegenerative disorders such as Alzheimer's disease (AD), which is characterized by the deposition of amyloid (A)β peptides and neuronal loss. Stimulating NSCs to replace lost neurons is therefore a promising approach for AD treatment. Our previous study demonstrated that osthole modulates NSC proliferation and differentiation, and may reduce Aβ protein expression in nerve cells. Here we investigated the mechanism underlying the effects of osthole on NSCs. We found that osthole enhances NSC proliferation and neuronal differentiation while suppressing apoptosis, effects that were exerted via activation of Wnt/β-catenin signaling. These results provide evidence that osthole can potentially be used as a therapeutic agent in the treatment of AD and other neurodegenerative disorders. [ABSTRACT FROM AUTHOR]

Cyclic guanosine monophosphate (GMP)-AMP (cGAMP) synthase (cGAS) is a universal double-stranded DNA (dsDNA) sensor that recognizes foreign and self-DNA in the cytoplasm and initiates innate immune responses and has been implicated in various infectious and non-infectious contexts. cGAS binds to the backbone of dsDNA and generates the second messenger, cGAMP, which activates the stimulator of interferon genes (STING). Here, we show that the endogenous polyamines spermine and spermidine attenuated cGAS activity and innate immune responses. Mechanistically, spermine and spermidine induced the transition of B-form DNA to Z-form DNA (Z-DNA), thereby decreasing its binding affinity with cGAS. Spermidine/spermine N1-acetyltransferase 1 (SAT1), the rate-limiting enzyme in polyamine catabolism that decreases the cellular concentrations of spermine and spermidine, enhanced cGAS activation by inhibiting cellular Z-DNA accumulation; SAT1 deficiency promoted herpes simplex virus 1 (HSV-1) replication in vivo. The results indicate that spermine and spermidine induce dsDNA to adopt the Z-form conformation and that SAT1-mediated polyamine metabolism orchestrates cGAS activity. [Display omitted] • Spermine and spermidine induce B-to-Z dsDNA transition in vivo • The binding affinity of Z-form dsDNA to cGAS was lower than that of B-DNA • Spermine and spermidine attenuate cGAS activation by promoting B-to-Z DNA transition • SAT1 facilitates cGAS activation by decreasing Spm/Spd level and Z-DNA accumulation The cytoDNA sensor cGAS recognizes B-DNA to initiate innate immunity, but whether different dsDNA conformations affect cGAS activity remains unknown. Zhao et al. demonstrate that spermine and spermidine induce B-to-Z DNA transition to suppress dsDNA binding to cGAS, and the polyamine catabolism enzyme SAT1 facilitates cGAS activation by inhibiting cellular Z-DNA accumulation. [ABSTRACT FROM AUTHOR]

Objective To determine the role of the MEKK1/SEK1/JNK1/AP-1 pathway in the action of Xihuang pill (XHP) in reducing regulatory T (Treg) cell numbers in the tumor microenvironment in a 4T1 mouse breast cancer model, and to clarify the anti-tumor mechanism of XHP in breast cancer. Methods We established a mouse 4T1 breast cancer model. Model mice were administered XHP for 2 weeks, and tumor tissues were then removed, weighed, sliced, and homogenized. Treg cells in the tumor microenvironment were isolated by magnetic cell sorting and analyzed by immunohistochemistry and flow cytometry. Treg cell apoptosis was detected by TdT-mediated dUTP nick end labeling. mRNA expression levels of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment were detected by quantitative real-time PCR and their protein expression levels were detected by immunofluorescence staining and western blot. Results Tumor weights were significantly lower in the XHP groups compared with the untreated control group. The overall number of Treg cells in the tumor microenvironment decreased while the number of apoptotic Treg cells increased with increasing doses of XHP. mRNA and protein expression levels of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment increased with increasing doses of XHP. Conclusion XHP might promote Treg cell apoptosis in the tumor microenvironment and further inhibit the tumor growth of 4T1 mouse breast cancer. The mechanism of XHP may be related to upregulation of gene and protein expression of MEKK1, SEK1, JNK1, and AP-1 in Treg cells in the tumor microenvironment. [ABSTRACT FROM AUTHOR]

Colon cancer is one of the deadliest cancers worldwide; abnormal microRNA expression is common during colon cancer development. The aim of the present study was to elucidate the role played by miR-185 in this context. We used quantitative real-time PCR (qRT-PCR) to measure miR-185 expression levels in colon cancer cell lines. The effects of miR-185 on colon cancer cell proliferation and invasion were assessed using the MTT, colony-forming, wound-healing, and transwell assays. A luciferase activity assay was used to confirm the target of miR-185. Our data showed that miR-185 was significantly down-regulated in colon cancer cells and colonic cancer tissues compared with NCM460 normal colonic epithelial cells and adjacent normal tissues. A functional analysis revealed that ectopic expression of miR-185 significantly inhibited colon cancer cell proliferation, colony formation, migration, and invasion. In addition, western blot, qRT-PCR, and luciferase assays confirmed in colon cancer cells that Wnt1 was a downstream target of miR-185, in turn suppressing β-catenin-mediated signaling. In conclusion, we found that miR-185 inhibits colon cancer cell proliferation and invasion by targeting Wnt1, and that it serves as a tumor suppressor, indicating that the modulation of miR-185 levels may potentially be therapeutic in colon cancer patients. [ABSTRACT FROM AUTHOR]

Mechanical brain injury (MBI) is a common neurotrosis disorder of the central nervous system (CNS), which has a higher mortality and disability. In the case of MBI, neurons death leads to loss of nerve function. To date, there was no satisfactory way to restore neural deficits caused by MBI. Endogenous neural stem cells (NSCs) can proliferate, differentiate and migrate to the lesions after brain injury, to replace and repair the damaged neural cells in the subventricular zone (SVZ), hippocampus and the regions of brain injury. In the present study, we first prepared a mouse model of cortical stab wound brain injury. Using the immunohistochemical and hematoxylin-eosin (H&E) staining method, we demonstrated that osthole (Ost), a natural coumarin derivative, was capable of promoting the proliferation of endogenous NSCs and improving neuronal restoration. Then, using the Morris water maze (MWM) test, we revealed that Ost significantly improved the learning and memory function in the MBI mice, increased the number of neurons in the regions of brain injury, hippocampus DG and CA3 regions. Additionally, we found that Ost up-regulated the expression of self-renewal genes Notch 1 and Hes 1. However, when Notch activity was blocked by the γ-secretase inhibitor DAPT, the expression of Notch 1 and Hes 1 mRNA was down-regulated, augmentation of NICD and Hes 1 protein was ameliorated, the proliferation-inducing effect of Ost was abolished. These results suggested that the effects of Ost were at least in part mediated by activation of Notch signaling pathway. Our findings support that Ost is a potential drug for treating MBI due to its neuronal restoration. [ABSTRACT FROM AUTHOR]

DNA methylation is an important epigenetic mechanism for phenotypic diversification in all forms of life. We previously described remarkable cell-to-cell heterogeneity in epigenetic pattern within a clonal population of Streptococcus pneumoniae, a leading human pathogen. We here report that the epigenetic diversity is caused by extensive DNA inversions among hsdSA , hsdSB , and hsdSC, three methyltransferase hsdS genes in the Spn556II type-I restriction modification (R-M) locus. Because hsdSA encodes the sequence recognition subunit of this type-I R-M DNA methyltransferase, these site-specific recombinations generate pneumococcal cells with variable HsdSA alleles and thereby diverse genome methylation patterns. Most importantly, the DNA methylation pattern specified by the HsdSA1 allele leads to the formation of opaque colonies, whereas the pneumococci lacking HsdSA1 produce transparent colonies. Furthermore, this HsdSA1-dependent phase variation requires intact DNA methylase activity encoded by hsdM in the Spn556II (renamed olony pacity eterminant or cod) locus. Thus, the DNA inversion-driven ON/OFF switch of the hsdSA1 allele in the cod locus and resulting epigenetic switch dictate the phase variation between the opaque and transparent phenotypes. Phase variation has been well documented for its importance in pneumococcal carriage and invasive infection, but its molecular basis remains unclear. Our work has discovered a novel epigenetic cause for this significant pathobiology phenomenon in S. pneumoniae. Lastly, our findings broadly represents a significant advancement in our understanding of bacterial R-M systems and their potential in shaping epigenetic and phenotypic diversity of the prokaryotic organisms because similar site-specific recombination systems widely exist in many archaeal and bacterial species. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a directional distance function approach to measure two technical efficiencies with respect to the two technologies characterized by strong and weak disposability of pollutants. The environmental efficiency index, defined as the ratio of the two technical efficiencies, reflects the opportunity cost to transform the strong disposability of pollutants into a weak one. The proposed approach is applied to measure the environmental efficiency index of the Chinese industrial sector, with the input and output data of the sector in 284 cities at the prefecture level and above in China from 2003 to 2009, including the emissions of wastewater, sulfur dioxide, and soot. Several factors of environmental efficiency are also investigated by using a panel Tobit model. [Copyright &y& Elsevier]