High detectivity Ge photodetector at 940†nm achieved by growing strained-Ge with a top Si stressor.

We have developed a self-powered near-infrared photodetector (PD) with high detectivity using a tensile strained Ge layer capped with a thick Si layer. The Si layer acts as a stressor and maintains the strain of Ge with minimal dislocations by creating a rough surface. By using Raman spectroscopy, we confirmed that the Ge layer has a 1.83% in-plane tensile strain. The Ge PD exhibits a high responsivity of 0.45 A/W at -1 V bias voltage for 940 nm wavelength. The PD's dark current density is as low as ∼1.50 × 10-6 A/cm2 at -1 V. The high responsivity and low dark current result in a detectivity as high as 6.55 × 1011 cmHz1/2/W. This Ge PD has great potential for applications in light detection and ranging (LiDAR), Internet of Things (IoTs), and Optical Sensing Networks.

SMAD4 endows TGF-ß1-induced highly invasive tumor cells with ferroptosis vulnerability in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive malignancy prone to recurrence and metastasis. Studies show that tumor cells with increased invasive and metastatic potential are more likely to undergo ferroptosis. SMAD4 is a critical molecule in the transforming growth factor ß (TGF-ß) pathway, which affects the TGF-ß-induced epithelial-mesenchymal transition (EMT) status. SMAD4 loss is observed in more than half of patients with PDAC. In this study, we investigated whether SMAD4-positive PDAC cells were prone to ferroptosis because of their high invasiveness. We showed that SMAD4 status almost determined the orientation of transforming growth factor ß1 (TGF-ß1)-induced EMT via the SMAD4-dependent canonical pathway in PDAC, which altered ferroptosis vulnerability. We identified glutathione peroxidase 4 (GPX4), which inhibited ferroptosis, as a SMAD4 down-regulated gene by RNA sequencing. We found that SMAD4 bound to the promoter of GPX4 and decreased GPX4 transcription in PDAC. Furthermore, TGF-ß1-induced high invasiveness enhanced sensitivity of SMAD4-positive organoids and pancreas xenograft models to the ferroptosis inducer RAS-selective lethal 3 (RSL3). Moreover, SMAD4 enhanced the cytotoxic effect of gemcitabine combined with RSL3 in highly invasive PDAC cells. This study provides new ideas for the treatment of PDAC, especially SMAD4-positive PDAC.

Quantitative mass spectrometric analysis of hepatocellular carcinoma biomarker alpha-fetoprotein.

Serum alpha-fetoprotein (AFP) has been used as a marker for the diagnosis of hepatocellular carcinoma (HCC) and its core fucosylation is associated with the early stage of HCC. However, current methods for the detection of AFP with core fucose are not highly accurate for early diagnosis. In this study, we established an enzyme-assisted mass spectrometric method for the quantitative analysis of AFP/core fucose with high specificity and sensitivity. We employed endoglycosidase treatment of AFP to improve the biomarker analysis. The accuracy and precision are within the US FDA-suggested value, and a good linearity (r2 = 0.9930) and a detection limit of 15.6 ng mL-1 can be achieved.

Drought stress-induced the formation of heteromorphic leaves of Populus euphratica Oliv: evidence from gene transcriptome.

Populus euphratica Oliv., a dominant species of arid desert community, grows heteromorphic leaves at different crown positions. Whether heteromorphic leaves are a strategy of plant adaptation to drought stress is rarely reported. This study sequenced the transcriptome of three typical heteromorphic leaves (lanceolate, ovate and broad-ovate leaves) of P. euphratica, and measured their drought stress. We wanted to reveal the molecular mechanisms underlying the formation of heteromorphic leaves. Drought stress was increased significantly from lanceolate to ovate to broad-ovate leaves. Gene ontology (GO) and KEGG enrichment analysis showed that the MADs-box gene regulated the expression of peroxidase (POD) in the phenylpropane biosynthetic pathway. The up-regulated expression of the chalcone synthase (CHS) gene in broad-ovate leaves significantly activated the flavonoid biosynthetic pathway. In the process of leaf shape change, the different expressions of homeodomain leucine zipper (HD-ZIP) among the three heteromorphic leaves had potential interactions on the AUX and ABA pathways. The expression of Sucrose phosphate synthase (SPS) and sucrose synthase (SUS) increased from lanceolate to broad-ovate leaves, resulting in a consistent change in starch and sucrose content. We concluded that these resistance-related pathways are expressed in parallel with leaf formation genes, thereby inducing the formation of heteromorphic leaves. Our work provided a new insights for desert plants to adapt to drought stress.

Progress in research of etiology of childhood obesity based on interaction between genes and environment / 中华流行病学杂志

Childhood obesity is a global public health problem, which can not only endangers children's health, but also might be an important cause of chronic diseases in adulthood. In recent years, with the in-depth development of precision medicine research, more and more research evidences have shown that there are interactions between environmental factors, such as early intrauterine environment, children's diet, physical activity and children's gene factor on the incidence of childhood obesity, which can result in or inhibit the incidence and development of childhood obesity. This paper summarizes the progress in research in this field to reveal the effects and potential mechanisms of genetic factors and environmental factors on the incidence of childhood obesity in order to provide reference for the precise prevention and control of childhood obesity under different genetic backgrounds.

A Computational Model of Blood D-Dimer, Cystatin C, and CRP Levels Predicts the Risk of Intracranial Aneurysms and their Rupture.

Objective: The aim of this study is to construct a computational model of blood D-dimer, cystatin C, and CRP levels and to predict the risk of intracranial aneurysms and their rupture. Methods: A total of 69 intracranial aneurysms patients were selected as the case group, including 28 cases in the ruptured group and 41 cases in the unruptured group. Another 64 non-intracranial aneurysm patients were selected as the control group. The detection results of serum D-dimer, cystatin C, and CRP were collected. The logistic regression computational model was used to analyze the occurrence and risk factors of intracranial aneurysms. The receiver operating curves (ROC) of serum D-dimer, cystatin C, and C reactive protein (CRP) levels for predicting intracranial aneurysms and their rupture were drawn, and the area under the curve (AUC), sensitivity, and specificity were calculated. Results: The serum levels of D-dimer, cystatin C, and CRP in patients with intracranial aneurysms were significantly higher than those in the control group and the differences were statistically significant (P < 0.05). The serum levels of D-dimer, cystatin C, and CRP in patients with ruptured intracranial aneurysms were higher than those in patients with unruptured intracranial aneurysms, and the differences were also statistically significant (P < 0.05). The combined detection of serum D-dimer, cystatin C, and CRP levels has a higher AUC (0.9014) for predicting intracranial aneurysms and higher AUC (0.9412) for predicting ruptured intracranial aneurysms than D-dimer (0.7118 and 0.8750, respectively), cystatin C (0.6489 and 0.6180, respectively), and CRP (0.7764 and 0.6551, respectively) independent detection; the combined detection had a sensitivity of 93.75% and 87.80 for predicting the occurrence and rupture of intracranial aneurysms, and the specificity was 68.12% and 92.86%, respectively. Conclusion: The combined detection of serum D-dimer, cystatin C, and CRP levels is a very valuable indicator for predicting the occurrence and rupture of intracranial aneurysms, and combined detection can provide scientific evidence-based guidance for clinical prediction of the occurrence and rupture of intracranial aneurysms.

100 Gb/s NRZ OOK signal regeneration using four-wave mixing in a silicon waveguide with reverse-biased p-i-n junction.

A silicon waveguide with reverse-biased p-i-n junction is used to experimentally demonstrate all-optical regeneration of non-return-to-zero (NRZ) on-off keying (OOK) signal based on four-wave mixing. The silicon waveguide allows a high conversion efficiency of -12 dB. The 0.22 dB (1.1 dB) quality (Q) factor and 0.74 dB (6.3 dB) extinction ratio (ER) improvements on average are achieved for 100 Gb/s (50 Gb/s) NRZ OOK signal regeneration at different receiving powers via the optimal match between the input signal optical power and input-output transfer curve. To the best of our knowledge, this silicon-based all-optical regenerator exhibits superior regeneration performance, including large ER and Q factor improvements, and the highest regeneration speed of NRZ OOK signal, and it has wide applications in 5 G/6 G networks.

[Effects of Continuous Straw Returning with Chemical Fertilizer on the Carbon Pool and Crop Yield of Rice-Rape Rotation Soils].

According to the positioning experiment of straw returning in the continuous field 7a, the effects of straw returning combined with chemical fertilizer on soil total organic carbon (TOC), dissolved organic carbon (DOC), particulate organic carbon (POC), labile organic carbon (LOC), carbon pool management index (CPMI), and crop yield in farmland soil profiles (0-20, 20-50, and 50-80 cm) in the Chaohu Lake area were studied. There were four treatments:no straw returning+no fertilization (CK), conventional fertilization (F), straw returning+conventional fertilization (SF1), and straw returning+80% conventional fertilization (SF2). The changes in soil total organic carbon and component content, CPMI, and rape rice yield in different soil layers were analyzed. Taking CK as a reference, conventional fertilization and straw returning combined with chemical fertilizer increased the content of total organic carbon and components in the soil vertical profile, and the content of total organic carbon and components in different soil layers decreased gradually with the increase in soil depth. In the 0-20 cm soil layer, compared with that in the F treatment, the SF1 and SF2 treatments significantly increased the contents of TOC, DOC, POC, and LOC by 14.23%-28.97%, 7.86%-27.01%, 16.46%-24.24%, and 5.89%-6.64%, respectively (P<0.05). In the 20-50 cm soil layer, the contents of TOC and LOC in SF1 were significantly increased by 9.43% and 8.34%, respectively, compared with those in the F treatment (P<0.05), and the contents of DOC and POC in SF2 were significantly increased by 17.51% and 65.83% compared with those in the F treatment (P<0.05). In the 50-80 cm soil layer, there was no significant difference in the contents of total organic carbon and components among the treatments. The effect of straw returning and chemical fertilizer on the soil carbon pool management index was significant. SF1 significantly improved the CPMI of the 0-50 cm soil layer compared with that in the F treatment, whereas the CPMI of the F treatment was the largest in the 50-80 cm soil layer; however, there was no significant difference among all treatments. Straw returning combined with chemical fertilizer had a significant effect on crop yield, and the yield of the SF1 treatment was the highest; compared with that of the F treatment, the rice, rape, and annual yields were significantly increased by 6.19%, 7.67%, and 6.54%, respectively (P<0.05). In general, straw returning combined with chemical fertilizer was of great significance to improve the soil carbon pool, soil fertility, and crop yield in the Chaohu Lake area.

[Effects of Interleukin-6 Gene Knockout on ß-amyloid Deposition and Cognition in 5×FAD Mouse Model of Alzheimer's Disease].

Objective To explore the effects of interleukin-6 (IL-6) gene knockout on the cognitive function and pathological changes in 5×FAD transgenic mice of Alzheimer's disease.Methods IL-6+/- mice were crossed with 5×FAD mice to establish the 5×FAD;IL-6-/- mouse model,and 3-month-old and 10-month-old mice were selected for experiments.The cognitive function of mice was detected by behavioral tests,and HE staining and ß-amyloid (Aß) immunohistochemical staining were performed to detect the pathological changes of mouse brain tissue.Results The number of 5×FAD;IL-6-/- model mice (3 months old,n=20;10 months old,n=5) and 5×FAD littermate control (3 months old,n=26;10 months old,n=24) conformed to the Mendel's law.Compared with that of the 5×FAD mice at the same age,the discrimination ratio of 3-month-old 5×FAD;IL-6-/- mice increased in the novel object recognition test (q=3.890,P=0.002).Morris water maze test results showed that the 3-month-old 5×FAD;IL-6-/- mice had longer time spent in target quadrant (q=3.797,P=0.012) and more times of crossing platform (q=2.505,P=0.017) than the 5×FAD mice at the same age.The results of immunohistochemical staining showed that IL-6 knockout reduced the Aß deposition in the hippocampus (q=13.490,P=0.002;q=45.680,P<0.001) and cortex (q=16.830,P=0.001;q=14.180,P=0.001) of 5×FAD mice.Conclusion IL-6 gene knockout can significantly improve the spatial memory and reduce the Aß deposition in the brain of 5×FAD mice.

Activation and blockade of 5-HT4 receptors in the dorsal hippocampus enhance working and hippocampus-dependent memories in the unilateral 6-hydroxydopamine lesioned rats.

Cognitive dysfunction is a common symptom in Parkinson's disease (PD). Serotonin4 (5-HT4) receptors are richly expressed in the dorsal hippocampus (dHIPP) and play an important role in cognitive activities. However, the mechanism underlying the role of dHIPP 5-HT4 receptors in PD-related cognitive dysfunction remains unclear. Here we found that unilateral 6-hydroxydopamine lesions of the medial forebrain bundle increased the protein expression of 5-HT4 receptors in the dHIPP, decreased hippocampal theta rhythm, and impaired working memory and hippocampus-dependent memory in the T-maze and hole-board test, respectively. Both activation and blockade of dHIPP 5-HT4 receptors (agonist BIMU8 and antagonist GR113808) improved working memory and hippocampus-dependent memory in the lesioned rats, but not in sham rats. Activation of dHIPP 5-HT4 receptors increased hippocampal theta rhythm in the lesioned rats. The neurochemical studies showed that injection of BIMU8, GR113808 or GR113808/BIMU8 in the dHIPP increased the levels of dopamine in the medial prefrontal cortex (mPFC), dHIPP and amygdala, and the level of 5-HT in the amygdala in the lesioned rats, but not in sham rats. Injection of GR113808 or GR113808/BIMU8 into the dHIPP also increased the levels of noradrenaline in the mPFC, dHIPP and amygdala only in the lesioned rats. These results suggest that activation or blockade of dHIPP 5-HT4 receptors may improve the cognitive impairments in parkinsonian rats, which may be due to the increase of hippocampal theta rhythm, up-regulated expressions of 5-HT4 receptors in the dHIPP and the changes in the levels of monoamines in the relative brain areas.

Lipophilic Constituents in Salvia miltiorrhiza Inhibit Activation of the Hepatic Stellate Cells by Suppressing the JAK1/STAT3 Signaling Pathway: A Network Pharmacology Study and Experimental Validation.

Liver fibrosis is currently a global health challenge with no approved therapy, with the activation of hepatic stellate cells being a principal factor. Lipophilic constituents in Salvia miltiorrhiza (LS) have been reported to improve liver function and reduce the indicators of liver fibrosis for patients with chronic hepatitis B induced hepatic fibrosis. However, the pharmacological mechanisms of LS on liver fibrosis have not been clarified. In this study, 71 active compounds, 342 potential target proteins and 22 signaling pathways of LS were identified through a network pharmacology strategy. Through text mining and data analysis, the JAK1/STAT3 signaling pathway was representatively selected for further experimental validation. We firstly confirmed the protective effect of LS on liver fibrosis in vivo by animal experiments. Hepatic stellate cells, which proliferated and displayed a fibroblast-like morphology similar to activated primary stellate cells, were applied to evaluate its underlying mechanisms. The results showed that LS could inhibit the cell viability, promote the cell apoptosis, decrease the expression of liver fibrosis markers, and downregulate the JAK1/STAT3 signaling pathway. These results demonstrated that LS could exert anti-liver-fibrosis effects by inhibiting the activation of HSCs and regulating the JAK1/STAT3 signaling pathway, which is expected to benefit its clinical application.

The dual-detection mode and improved photoresponse of IGZO-based photodetectors by interfacing with water-soluble biomaterials.

The use of conventional fabrication methods rapidly developed the performance and notable enhancements of optoelectronic devices. However, it proved challenging to develop and demonstrate stable optoelectronic devices with biodegradability and biocompatibility properties towards sustainable development and extensive applications. This study incorporates a water-soluble Cr-phycoerythrin (Cr-PE) biomaterial to observe its optical and electronic properties effects on the pristine indium gallium zinc oxide (IGZO)-based photodetector. The fabricated photodetector demonstrates an extended absorption detection region, enhanced optoelectronic performance, and switchable function properties. The resulting photocurrent and responsivity of the IGZO/Cr-PE structure have increased by 5.7 and 7.1 times as compared to the pristine IGZO photodetector. It was also observed that the photodetector could operate in UV and UV-visible with enhanced optical properties by effectively adding the water-soluble Cr-PE. Also, the sensing region of IGZO photodetector becomes changeable. It exhibits switchable dual detection by alternatively dripping and removing the Cr-PE on the IGZO layer. Different measurement parameters such as detectivity, repeatability, and sensitivity are highlighted to effectively prove the advantage of including Cr-PE on the photodetector structure. This study contributes to understanding the potential functions in improving optoelectronic devices through an environmental-friendly method.

Fucoidan from Sargassum hemiphyllum inhibits infection and inflammation of Helicobacter pylori.

Having infected by Helicobacter pylori, the infection often leads to gastritis, gastric ulcer, or even gastric cancer. The disease is typically treated with antibiotics as they used to effectively inhibit or kill H. pylori, thus reducing the incidence of gastric adenoma and cancer to significant extent. H. pylori, however, has developed drug resistance to many clinically used antibiotics over the years, highlighting the crisis of antibiotic failure during the H. pylori treatment. We report here that the fucoidan from Sargassum hemiphyllum can significantly reduce the infection of H. pylori without developing to drug resistance. Fucoidan appears to be a strong anti-inflammation agent as manifested by the RAW264.7 cell model examination. Fucoidan can prohibit H. pylori adhesion to host cells, thereby reducing the infection rate by 60%, especially in post treatment in the AGS cell model assay. Mechanistically, fucoidan intervenes the adhesion of BabA and AlpA of H. pylori significantly lowering the total count of H. pylori and the level of IL-6 and TNF-α in vivo. These results all converge on the same fact that fucoidan is an effective agent in a position to protect the stomach from the H. pylori infection by reducing both the total count and induced inflammation.

Sex differences in short- and mid-term survival of femoral neck fracture in patients aged over 90 years: A retrospective cohort study.

OBJECTIVES: The primary purpose of this retrospective study was to evaluate the sex differences in short- and mid-term mortality in femoral neck fracture patients aged >90 years treated operatively and nonoperatively over a 10-year period. METHODS: From January 2007 to December 2016, all femoral neck fractures patients (aged over 90 years) admitted to our hospital were included for evaluation. The survival time and mortality rate were compared between patients treated by arthroplasty and those treated nonoperatively. Additionally, a Cox proportional hazards model was built to explore the treatment effect difference between the arthroplasty group and the nonoperative group with sex-stratified subgroups. RESULTS: The difference in the survival distribution between the nonoperative and arthroplasty groups were significant for women (P = 0.002) but not for men (P = 0.6222). The adjusted hazard ratio (95% confidence interval) of nonoperative treatment to arthroplasty was 3.93 (1.86, 8.31). The adjusted risk ratios of nonoperative treatment to arthroplasty for males and females were 1.24 (0.58, 2.67) and 34.04 (8.68, 133.47), respectively. The data also showed higher short- and midterm survival rates in women than in men among the arthroplasty group, especially within the first 1-3 years after injury. CONCLUSIONS: Arthroplasty can significantly improve short- and mid-term survival in femoral neck fracture patients aged over 90 years, especially females. The most significant difference in mortality between the two sexes was observed within the first three years following the fracture.

A Lightweight Encoder-Decoder Path for Deep Residual Networks.

In this article, we present a novel lightweight path for deep residual neural networks. The proposed method integrates a simple plug-and-play module, i.e., a convolutional encoder-decoder (ED), as an augmented path to the original residual building block. Due to the abstract design and ability of the encoding stage, the decoder part tends to generate feature maps where highly semantically relevant responses are activated, while irrelevant responses are restrained. By a simple elementwise addition operation, the learned representations derived from the identity shortcut and original transformation branch are enhanced by our ED path. Furthermore, we exploit lightweight counterparts by removing a portion of channels in the original transformation branch. Fortunately, our lightweight processing does not cause an obvious performance drop but brings a computational economy. By conducting comprehensive experiments on ImageNet, MS-COCO, CUB200-2011, and CIFAR, we demonstrate the consistent accuracy gain obtained by our ED path for various residual architectures, with comparable or even lower model complexity. Concretely, it decreases the top-1 error of ResNet-50 and ResNet-101 by 1.22% and 0.91% on the task of ImageNet classification and increases the mmAP of Faster R-CNN with ResNet-101 by 2.5% on the MS-COCO object detection task. The code is available at https://github.com/Megvii-Nanjing/ED-Net.

Topical application of fucoidan derived from Cladosiphon okamuranus alleviates atopic dermatitis symptoms through immunomodulation.

Atopic dermatitis (AD) is a T helper (Th) 2 cell-mediated allergic disease, which features increased number of immunocytes and level of Th2-associated cytokines. Fucoidan is well known a naturally occurring agent effectively ameliorating many AD symptoms. Though these alleviative effects are exhilarating, the mechanisms behind, however, are still rather limited. In this study, we report that fucoidan derived from Cladosiphon okamuranus (FT) inhibits nitric oxide (NO) production by exerting its anti-inflammatory ability. Topical application on animals show that FT promotes skin repair, reduces immunocyte proliferation, and decreases serum IgE level. In histological analysis, FT favorably reduces epidermal hyperplasia and eosinophilic infiltration. The pharmacodynamics mechanism of FT is determined by means of down-regulating AD-associated cytokines (IL-4, IL-5, IL-22, IL-33, and TSLP) and up-regulating TGF-ß1 level. Moreover, FT can regulate systemic immunity by enhancing tolerogenic dendritic cells (Tol-DCs) to activate regulatory T cells (Treg) differentiation and to decrease the population of Th22 and memory B cells. Overall, topical application of FT is able to enhance Treg secreting TGF-ß1 and to down-regulate Th2 cell-mediated immunity so that AD symptoms are significantly alleviated. Thereby, FT is an ideal drug candidate potentially replacing or complementing corticosteroids to be developed and used as a therapeutic agent to treat AD.

Ultrahigh spectral resolution single passband microwave photonic filter.

Microwave photonic filters (MPFs) with only one ultra-narrow passband are able to provide high frequency selectivity and wide spectral range, and they are of great importance in radio-frequency (RF) signal processing. However, currently all MPFs are limited by trade-offs between key parameters such as spectral resolution and range, tunability, and stability. Here, we report the first demonstration of a single passband MPF with unprecedented performance including ultrahigh spectral resolution of 650 kHz, 0-40 GHz spectral range, and high stability of center frequency drifting within ±50 kHz. This record performance is accomplished by breaking the amplitude equality of a phase-modulated signal via a Brillouin dynamic grating (BDG) which has an ultra-narrow reflection spectrum of sub-MHz. The results point to new ways of creating high performance microwave photonic systems, such as satellite and mobile communications, radars, and remote-sensing systems.

Clinical Application of the Musculoperiosteal Iliac Flap for Osteonecrosis of the Femoral Head.

BACKGROUND: Osteonecrosis of the femoral head (ONFH) often affects young, active patients, and the femoral head's preservation is the primary goal of treatment for this disease. Vascularized iliac crest bone grafting is one of the many vascularized procedures used in treating ONHF. In some cases, we selectively performed this procedure using the musculoperiosteal iliac flap with the ascending branch of the lateral femoral circumflex artery for ONFH treatment. METHODS: Twelve patients (12 hips) with nontraumatic femoral head necrosis underwent musculoperiosteal iliac flap transfer with the ascending branch of the lateral femoral circumflex artery. The Harris Hip Score (HHS), visual analog scale score, and double-hip X-ray findings were used to analyze hip function changes within 10 days preoperatively and 6 and 12 months postoperatively. RESULTS: The mean HHS increased from 52.33 ± 3.34 preoperatively to 65.92 ± 5.04 6 months postoperatively and 79.75 ± 3.84 12 months postoperatively, and the data showed a statistical significance difference between preoperative and postoperative (F = 131.90, P < 0.01). The HHS at 6 and 12 months after surgery were significantly different (P < 0.01). The visual analog scale score showed the same trend. The x-ray of hip joints at 6 and 12 months after surgery showed that the femoral heads' shape and contour were good, femoral heads did not collapse, and the transferred bone flaps healed well. CONCLUSIONS: Musculoperiosteal iliac flap transfer with the ascending branch of the lateral femoral circumflex artery may be an effective method with a high clinical success rate for treating young patients with early to midstage ONFH.

HCE: Hierarchical Context Embedding for Region-Based Object Detection.

State-of-the-art two-stage object detectors apply a classifier to a sparse set of object proposals, relying on region-wise features extracted by RoIPool or RoIAlign as inputs. The region-wise features, in spite of aligning well with the proposal locations, may still lack the crucial context information which is necessary for filtering out noisy background detections, as well as recognizing objects possessing no distinctive appearances. To address this issue, we present a simple but effective Hierarchical Context Embedding (HCE) framework, which can be applied as a plug-and-play component, to facilitate the classification ability of a series of region-based detectors by mining contextual cues. Specifically, to advance the recognition of context-dependent object categories, we propose an image-level categorical embedding module which leverages the holistic image-level context to learn object-level concepts. Then, novel RoI features are generated by exploiting hierarchically embedded context information beneath both whole images and interested regions, which are also complementary to conventional RoI features. Moreover, to make full use of our hierarchical contextual RoI features, we propose the early-and-late fusion strategies (i.e., feature fusion and confidence fusion), which can be combined to boost the classification accuracy of region-based detectors. Comprehensive experiments demonstrate that our HCE framework is flexible and generalizable, leading to significant and consistent improvements upon various region-based detectors, including FPN, Cascade R-CNN, Mask R-CNN and PA-FPN. With simple modification, our HCE framework can be conveniently adapted to fit the structure of one-stage detectors, and achieve improved performance for SSD, RetinaNet and EfficientDet.